Title of Invention	"A MINIATURISED DEVICE FOR PRODUCING HIGH PRESSURE IN A FLUID "
Abstract	A miniaturised device for producing high pressure in a fluid imposes stringent requirements on the manufacturing process. The device according to the invention consists of a hollow piston displacably mounted in a cylinder and a valve member which is guided by the hollow piston and mounted so as to be axially movable relative to the hollow piston. The valve member is arranged at one end of the hollow piston inside or immediately in front of the end of the hollow piston. The device is used in a mechanically operated high pressure atomiser. This consists of a two part housing which comprises a pump housing with nozzle, a blocking mechanism, a spring housing with spring, a non-pressurised storage container for the fluid and a mechanical counter integrated in the spring housing. The valve operates without any auxiliary force, closes very rapidly and is sealed tight against high pressure. The atomiser is safe and simple to operate and environmentally friendly. The fluid is metered extremely accurately. The atomiser is used, for example, to produce an inhalable aerosol of a liquid medicament without the use of propellant gas, at 320 bar, for example.

Title of Invention

"A MINIATURISED DEVICE FOR PRODUCING HIGH PRESSURE IN A FLUID "

Abstract

A miniaturised device for producing high pressure in a fluid imposes stringent requirements on the manufacturing process. The device according to the invention consists of a hollow piston displacably mounted in a cylinder and a valve member which is guided by the hollow piston and mounted so as to be axially movable relative to the hollow piston. The valve member is arranged at one end of the hollow piston inside or immediately in front of the end of the hollow piston. The device is used in a mechanically operated high pressure atomiser. This consists of a two part housing which comprises a pump housing with nozzle, a blocking mechanism, a spring housing with spring, a non-pressurised storage container for the fluid and a mechanical counter integrated in the spring housing. The valve operates without any auxiliary force, closes very rapidly and is sealed tight against high pressure. The atomiser is safe and simple to operate and environmentally friendly. The fluid is metered extremely accurately. The atomiser is used, for example, to produce an inhalable aerosol of a liquid medicament without the use of propellant gas, at 320 bar, for example.

Full Text	The present invention relates to a miniaturised device for producing high pressure in a fluid. Tne invention relates to a device for producing high pressure in a fluid. It consists of a piston which is movable in a cylinder, and a valve, both of miniaturised construction. The invention further relates to a high pressure atomiser which contains this device, and the use thereof, preferably for medicinal purposes. The aim of the invention is to enable a device of this kind and the atomiser containing the device to be made simpler in design and cheaper to produce. In liquid chromatography (HPLC), for example, generally relatively small quantities of liquid are conveyed at high pressure through the separating column. Moreover, in medicinal aerosol therapy, aerosols are used, by atomising or nebulising liquid drugs for treating diseases of the respiratory tract in humans or for treating asthmatic conditions. Here again, a high pressure is required in a, generally relatively small, quantity of fluid, in order to produce the small droplet size needed for the aerosol. In the nebulizer according to WO-91/14458 a given volume of; a fluid is sprayed through a nozzle with a small aperture .under a pressure of between 5 and 40 MPa {about 50 to 400 bar) to produce an aerosol. The aim of the invention is to provide a device suitable for producing high pressure in a fluid and. an atomiser containing this device, the device for producing high, pressure being easier to produce and optimally adapted to its function, preferably in a high pressure atomiser. The first part of this problem is solved according to the invention by a devic for producing high pressure in a fluid, of miniaturised constrution, consisting of a piston which is movable in a cylinder, a high pressure chamber located in front of the piston inside the cylinder, and a valve, characterised by: a cylindrical hollow piston, a valve member which is guided by the hollow piston and: is mounted so as to be axially movable against the hollow piston, a stop means on the hollow piston which holds the valve member together with the hollow piston, and a defined sealing surface at the inlet end of the valve member. In the specification which follows, the terms inlet and outlet side or inlet and outlet end are used in relation to the main direction of flow of the fluid within the device. The valve member is somewhat displaceable against the hollow piston but it moves substantially with the hollow piston. The valve member is preferably uniaxially rotationally symmetrical in shape, e.g. it is a circular cylinder or a frustum. Its cross-section is somewhat smaller than the cross- sect ion of the chamber in which Che valve member is movably mounted. This is achieved by means of one or more channels preferably extending in the outer surface of the cylindrical valve member, or by a somewhat smaller diameter of the valve member in relation to the diameter of the chamber in which the valve member is movably mounted. The valve member is guided in the chamber in which it is movably mounted; the cylindrical valve member can rotate about its axis as required, but its axis always remains parallel to the axis of the hollow piston. This produces a defined sealing surface at the inlet of the valve member. The distance over which the valve member can travel relative to the hollow piston is limited by a stop or stop means which holds the movable valve member together with the hollow piston. In the region of the outlet end of the valve member there is at least one recess to enable the fluid to flow through between the stop and the valve member when the valve is open. The or each recess is located either in the valve member at the outlet end thereof or in the stop in the hollow piston. In the position where the valve member abuts on the stop of the hollow piston, the valve is opened. In the position where the valve member abuts on the defined sealing surface, the valve is closed. The valve member arranged inside the hollow piston has virtually no friction against the inner wall of the hollow piston. The valve member arranged directly in front of the end of the hollow piston may possibly rub against the wall of the cylinder. In this case, the valve is actively closed and opened as the hollow piston moves, on account of the friction between the valve member and the cylinder wall. The cylinder preferably consists of plastics and the hollow piston of metal or plastics. The material for the valve member is selected, in terms of its hardness, to complement the hardness of the material for the hollow piston and may be metal, ceramics, glass, gemstone, plastics or elastomer. The valve member is preferably manufactured in one piece. When the fluid is sucked in, the high pressure chamber is connected to the fluid supply by means of the channels in the valve member. During the intake stroke of the hollow piston the fluid flows through the hollow piston and past the valve member into the high pressure chamber of the cylinder. During the exhaust stroke of the hollow piston the valve is sealed in high pressure tight manner against the defined sealing surface of the valve member. The device according to the invention for producing high pressure in a fluid is connected to the fluid supply at its inlet end. The high pressure chamber is connected to another device into which or through which the fluid is conveyed under high pressure. The hollow piston or the cylinder is attached to a drive which brings about relative movement between the hollow piston and cylinder and which applies the force required to generate the high pressure. In the first embodiment, the cylindrical valve member may be guided and mounted in axially mcvable manner directly in front of the end of the hollow piston, the diameter of the valve member being substantially equal to the internal diameter of the cylinder. On the outside, near its outlet end, the hollow piston has an encircling, preferably turned or shaped groove as a stop member, into which a plurality of snap hooks mounted on the valve member engage. Instead of the groove, the hollow piston may have at its outlet end a shaped taper with an encircling, outwardly funnel-shaped edge. The outer diameter of the hollow piston at its outlet end is greater than the base diameter of the groove and less than the diameter of the cylinder. Instead of the encircling groove, the outlet end of the hollow piston may be provided on the outside, at several, preferably 2 diametrically opposed points, with flattened areas which form a step to act as a stop means. The flat end of the hollow piston is the defined sealing surface. The outer edge at the end of: the hollow piston may be chamfered. In the second embodiment, the cylindrical valve member may be guided and movably mounted directly in front of the end of the hollow piston, the diameter of the valve member being substantially equal to the internal diameter of the cylinder. The end of the hollow piston is shaped inwardly and acts as a stop means. On the valve member is mounted a coaxial, undercut, mushroom-shaped peg the snap hooks of which engage behind the shaped edge of the hollow piston. The defined sealing surface rests on the outside of the piston at the shaped edge. In the third embodiment, the preferably cylindrical valve member may be mounted so as to be fully movable inside the hollow piston. The outlet end of the hollow piston has an internal diameter greater than the internal diameter of the remainder of the hollow piston. The length of this widened portion of the hollow piston is somewhat greater than the length of the valve member. The diameter of the valve member is substantially equal to the inner diameter at the widened end of the hollow piston. The outlet end of the hollow piston is shaped inwardly either over its entire periphery or over a part of its periphery and acts as a stop which holds the valve member inside the hollow piston. The base of the widened portion which forms the defined sealing surface may be flat or conical. The recess in the valve member may, for example, take the form of a stepped channel. The recess in the stop may be constructed, for example, as an indentation. In a variant of this embodiment, the valve member may be arranged totally inside the hollow piston at the inlet end thereof. The stop will then be located at the outlet end of the widened portion and the defined sealing surface will then be on the shaped edge at the inlet end of the hollow piston. In the fourth embodiment, the hollow piston consists of a thin-walled tube which is shaped at its end projecting into the cylinder and is provided with an encircling constriction at the end of the space allowed for the valve member. The cylindrical valve member is guided and movably mounted in the space between the shaped edge and the encircling constriction. Another thick-walled tube may be pushed into the inlet end of the hollow piston, its outer diameter being equal to the inner diameter of the hollow piston, and this thick-walled tube further being fixedly connected to the hollow piston and preferably extending approximately up to the encircling constriction in the hollow piston. The thick-walled tube acts as a displacement member and makes it easier for the fluid to be sucked into the high pressure chamber virtually without pressure. The thick-walled tube is preferably made of plastics. In a variant of this embodiment, the valve member may be mounted fully inside the hollow piston at the inlet end thereof, The stop is then located at the encircling constriction and the defined sealing surface is located at the shaped edge at the inlet end of the hollow piston. In the fifth embodiment, the hollow piston comprises a thin-walled tube which contains a thick-walled tube the outer diameter of which is equal to the inner diameter of the hollow piston, and which is fixedly connected to the hollow piston. The thick-walled tube functions as a displacement body and makes it easier for the fluid to be sucked in virtually without pressure. The inlet end of the hollow piston is widened. At the widened end, the hollow piston is fixedly connected to a closure member the outer diameter of which is greater than the outer diameter of the widened inlet end of the hollow piston. The closure member contains a depression which is open on its side facing the widened end of the hollow piston. In the base of the depression is an opening acting as an inlet for the fluid. The base of the depression may be conical or flat; it forms the defined sealing surface. The valve member is arranged in the depression, in the closure member; it. is guided so as to be axially movable in the depression. The external diameter of the valve member is smaller than the internal diameter of the depression, but preferably greater than the internal diameter of the hollow piston in that part of it which projects into the cylinder. The valve member may contain, at its outlet end, at least one recess through which the fluid flows into the high pressure chamber during the intake stroke of the hollow piston. The stop for the valve member is preferably the end of the displacement body which projects into the widened portion or the hollow piston, or if the end of the displacement body is located in the unwidened portion of the hollow piston - the transition from the unwidened portion of the hollow piston into the widened inlet end thereof. The hollow piston, with the widened inlet end preferably consists of metal. The displacement body and closure member are preferably made of plastics. The valve member may be made of plastics or metal. Of particular significance is the use of the device according to the invention for producing high pressure in a fluid in an atomiser (nebulizer) for propellent-free spraying of the fluid. The second part of the objective is achieved according to the invention by an atomiser for spraying a fluid, consisting of an upper housing part, a pump housing, a nozzle, a blocking mechanism, a spring housing, a spring and a supply container, characterised by a pump housing fixed in the upper housing part, which has at one end a nozzle member with the nozzle, a hollow piston with valve member, a drive flange in which the hollow piston is secured and which is located in the upper housing part, a blocking mechanism located in the upper housing part, a spring housing with the spring located therein, which is rotatably mounted by means of a rotary bearing on the upper housing part, a lower housing part which is fitted onto the spring housing in the axial direction. The hollow piston with valve member corresponds to one of the devices according to the invention mentioned hereinbefore. It projects partially into the cylinder of the pump housing and is mounted in axially movable manner in the cylinder. The hollow piston with valve member exerts a pressure of 5 to 60 MPa (about 50 to 600 bar) , preferably 10 to 60 MPa (about 100 to 600 bar) on the fluid at its high pressure end at the moment of release of the spring. The nozzle in the nozzle member is preferably microstructured, ie. produced by microtechnology. Microstructured nozzle members are disclosed, for example, in #0-94/07607; we hereby refer to the contents of this specification. The nozzle member consists, for example, of two plates of glass and/or silicon firmly joined together, of which at least one plate has one or more microstructured channels which connect the nozzle inlet end to the nozzle outlet end. At the nozzle outlet end is at least one circular or non-circular opening less than or equal to 10µm in size. The directions of. spraying of the nozzles in the nozzle member may run parallel to one another or may be inclined relative to one another. In a nozzles member having at least two nozzle openings at the outlet end, the directions of spray may be inclined relative to one another at an angle from 20 to 160", preferably at an angle from 60 to 150°. The directions of spraying meet in the vicinity of the nozzle openings. In the pump housing, a non-return valve with or without spring bias may be provided between the nozzle opening and the high pressure chamber of the cylinder. This non-return valve closes off the high pressure chamber in the resting state of the atomiser, protects the fluid from the entrance of air and may if necessary prevent volatile components of the fluid from evaporating out of the pump housing. The non-return valve opens automatically as soon as the pressure of the fluid in the high pressure chamber exceeds a minimum value and the current of fluid is created; it closes automatically as soon as the current of fluid is exhausted. The non-return valve may be, for example, a t ball valve. It may also consist of a flexible plate which is clamped on one side and rests like a flap on the outlet end of the high pressure chamber. In another embodiment it may consist of a disk of preferably flexible material, clamped all the way round, pierced by a pin. The pierced hole allows the current of fluid to pass through to the nozzle as soon as the pressure in the fluid exceeds a minimum value. After the current of fluid is exhausted, the pin hole closes up again. The valve member is preferably mounted at the end of the hollow piston facing the nozzle member. The blocking mechanism contains a spring, preferably a cylindrical helical compression spring, as a store for mechanical energy. The spring acts on the driven flange as a jumping member the movement of which is determined by the position of a blocking member. The path of travel of the driven flange is precisely defined by an upper and lower stop. The spring is preferably tensioned by an external torque via a power stepping-up gear, eg. a helical thrust gear, which is generated as the upper housing part rotates counter to the spring housing in the lower housing part. In this case, the upper housing part and the driven flange contain a single or multiple wedge gear. The blocking member with engaging blocking surfaces is arranged -in an annular configuration around the driven flange. It consists, for example, of a. plastics or metal ring which is inherently radially resiliently deformable. The ring is arranged in a plane at right angles to the atomiser axis. After the biassing of the spring, the blocking surfaces of the blocking member move into the path of the driven flange and prevent the spring from being released. The blocking member is actuated by a button. The actuating button is connected or coupled to the blocking member. In order to actuate the blocking mechanism the actuating button is pushed parallel to the plane of the ring, preferably into the atomiser; the deformable ring is thereby deformed in the plane of the ring. The atomiser optionally contains a mechanical counter consisting of a spindle with rotational barrier which is mounted on the spring housing. The axis of the spindle extends in the region of the outer surface parallel to the axis of the atomiser. The spindle is mounted, in the region of its ends, by means of a rotary bearing on the spring housing. The spindle has teeth at the end closest to the upper housing part. On the edge of the upper housing part is at least one cam which, engages in the teeth at the end of the spindle when the two housing parts are rotated relative to one another. A slider with rotation prevention means sits on the spindle. The lower housing part is pushed axially over the spring housing and covers the mounting, the drive of the spindle and the storage container for the fluid. The position of the slider is visible through a recess in the lower housing part and can be read off on a scale, eg. on the lower housing part. When the atomiser is actuated the upper housing part is rotated relative to the lower housing part, the lower housing part carrying the spring housing with it. The spring meanwhile is compressed and biassed by means of the helical thrust gear, and the blocking mechanism engages automatically. The angle of rotation is preferably a whole-number fraction of 360º, eg. 180º. At the same time as the spring is biassed, the driven part in the upper housing part is moved a certain distance, the hollow piston is retracted inside the cylinder in the pump housing, as a result of which some of: the fluid is sucked out of the storage container into the high pressure chamber in front of the nozzle. By means of the gears, which consist of the teeth on one end of the spindle and the or each cam on the edge of the upper housing part, the relative movement of the two housing parts is picked up and converted into a rotary movement of the spindle and displacement of the slider on the spindle. On each actuation of the atomiser, the slider is moved a certain distance along the spindle. The position of the slider indicates what proportion of the fluid to be atomised has already been taken from the storage container and how much is still available. The slider on the spindle can be reset if necessary by means of a resetting lug. If desired, a plurality of replaceable storage containers holding the fluid which is to be atomised can be inserted into the atomiser one after another and used. The storage container is not pressurised or substantially-not pressurised. The pressure of the fluid in the storage container is in any case substantially lower than the pressure generated in the high pressure chamber by the mechanically operated atomiser. The storage container contains, for example, a fluid containing a drug. The atomising process is started by gently pressing the actuating button. The blocking mechanism then opens up a path for the driven part to move. The biassed spring pushes the piston into the cylinder of the pump housing. The fluid leaves the nozzle of the atomiser in spray form. The components of the atomiser are made of a material which is suitable for the function. The housing of the atomiser and, insofar as function allows, other parts are preferably made of plastics, eg. by injection moulding. For medicinal purposes, physiologically acceptable materials are used. The atomiser according to the invention is used, for example, for propellant-free production of medicinal aerosols. An inhalable aerosol with an average particle size of about 5 µm can be produced thereby. The following active substances are mentioned by way of example of pharmaceutical compositions in the form of aqueous or ethanolic solutions, depending ,cn the solubility of the active substance: berotec, berodual, flunisolide, atrovent, salbutamol, budesonide, combivent, tiotropium, oxivent and suitable peptides. The solutions may also contain pharmaceutically acceptable excipients.. The device according to the invention for producing high pressure in a fluid and the atomiser containing this device have the following advantages: The device contains a valve which operates without any auxiliary force (produced by a spring) and closes as a result of the flow resistance of the fluid on the valve member or as a result of the friction on the cylinder wall. The valve is tight against a pressure generally above 3 MPa (30 bar) . The valve member is made in one piece; it is easy to manufacture and assemble. The valve closes very rapidly owing to the short distance travelled by the valve member to reach the defined sealing surface. The valve has a high sealing action. As a result of the guiding of the uniaxially rotationally symmetrical valve member, a defined sealing surface is produced which is high pressure tight through a very large number of cycles of movement of the hollow piston. The dead space of the high pressure chamber can be kept extremely small. The atomiser can be operated safely and easily even by untrained persons, both to bias the spring and to actuate the atomising process. The atomiser works without propellant gas and is therefore environmentally friendly. The storage container for the fluid is not pressurised or substantially not pressurised. The movement of the blocking member is automatically coupled, by a simple method, to the rotary movement for Massing the spring. In a preferred embodiment the atomiser consists of low-wear purely mechanical components and operates reliably over long periods. Owing to the defined abutments for the driven part the metering of the fluid is very accurate. The atomiser can be manufactured cheaply and assembled easily. The mechanical counter is automatically advanced as the atomiser is actuated; it is uncritical of tolerance, easy to assemble and operates safely and reliably. The counter is inaccessible when the atomiser is used properly and cannot be falsified by accident. The counter can be adapted to any number of releases of fluid from the storage container and to different overall numbers of storage containers to be used with one atomiser. The counter is integrated in the atomiser and does not take up any additional space. No substances can pass from the counter into the substance which is to be atomised. The device according to the invention for producing high pressure in a fluid and the atomiser containing this device are explained more fully with reference to Figures l to 6. Figure la shows a longitudinal section, viewed obliquely, through the first embodiment of the device according to the invention for producing high pressure in a fluid. In the cylinder (1) is the hollow piston (2) with the coaxial bore (7) and the valve member (3) in the partly open position of the valve. Between the bottom of the valve member (3) and the end of the cylinder is the high pressure chamber (4). The high pressure chamber is closed off by another component (not shown). Mounted on the hollow piston, outside the cylinder, is a device (non shown) by means of which the hollow piston can be displaced inside the cylinder. Figure ib shows the hollow piston (2) viewed obliquely. The end of the hollow piston facing the valve member is provided with a groove (5) which is bounded, at its end facing the valve member, by a step (8) the diameter of which is less than the external diameter of the hollow piston (2) and greater than the base diameter of the groove. The front edge at the end of the hollow piston may be chamfered. Figure 1c shows the valve Timber (3) viewed obliquely, it has, for example, three channels (9) on its outer surface. Mounted on the valve member (3), on its side facing the hollow piston, are, for example, three snap hooks (6) the width of which, in the direction of the circumference of the valve member, is less than a third of this circumference. The snap hooks (6) are shorter in the axial direction than the length of the, for example, gxooved end of the hollow piston. During assembly, the valve member {3) is placed on the end of the hollow piston (2), and the hooks (10) slide into the groove. The hollow piston together with the valve member is then pushed into the cylinder. When the valve is open, the inner edge o£ the hooks (10) abut on the step (8). When the valve is closed, the base of the valve member (3) facing the hollow piston fits tightly on the end of the hollow piston (2) which acts as the defined sealing surface. In order to take in the fluid, the hollow piston is lifted partly out of the cylinder, whereupon the valve automatically opens. The fluid flows through the bore (7) in the hollow piston and past the valve member into the high pressure chamber (4) . In order to expel the fluid, the hollow piston (2) is pushed into the cylinder (1), whereupon the valve closes automatically, virtually instantly, and high pressure is generated in the fluid. Figure 2a shows the second embodiment of the device according to the invention for producing high pressure in a fluid as a longitudinal section viewed obliquely. In the cylinder (1) is the hollow piston (11) and the valve member (13) in the partly open position of the valve. Figure 2b shows a longitudinal section through the" hollow piston (11) with the shaped outlet end (12) of the hollow piston. The displacement body (26) may be located in the hollow piston. Figure 2c shows the valve member (13) as a longitudinal section viewed obliquely. Mounted on the valve member is a coaxial, undercut peg (14) the projecting end of which engages behind the shaped edge (12) of the hollow piston. The end (15) of the peg facing the hollow piston may be chamfered. The peg may have an indentation (16) extending in the axial direction so that the peg can be pushed into the shaped end of the hollow piston, thereby engaging behind the shaped edge. Figure 3a shows the third embodiment of the device according to the invention for producing high pressure in a fluid in longitudinal section viewed obliquely, in the cylinder (1) is the hollow piston (17) and the valve member (18) in the closed position of the valve. Figure 3b shows a longitudinal section viewed obliquely through the hollow piston (17) with the shaped end (19) . At the outlet end of the hollow piston IB the widened portion (20) in which the valve member (18) is guided and mounted in axially movable manner. The inlet end of the widened portion (20) is chamfered or flat. Figure 3c shows the cylindrical valve member (18) in longitudinal section viewed obliquely. Both bases of the valve member are planar and are located perpendicularly to the axis of the valve member. The valve member (18) contains, for example, four stepped channels (21) on its outer surface. The edge of the valve member (18) which abuts on the inclined base of the hollow chamber (20) may be chamfered. The diameter of the valve member (18) is less than the diameter of the widened portion (20) so that the valve member (18) can move virtually without friction in the widened portion (20). For assembly, the valve member (18) is pushed into the widened portion (20) before the outlet end (19) of the hollow piston is shaped. Figure 4a shows the fourth embodiment of toe device according to the invention for producing high pressure in a fluid in longitudinal section viewed obliquely. In the cylinder (1) are the hollow piston (22) and the valve member (23) in the closed position of the valve. The diameter of the valve member is Icoo than the inner diameter of the hollow piston. Figure 4b shows a longitudinal section, viewed obliquely, through the hollow piston (22) with the shaped outlet end (24) and the encircling constriction (25). The thick-walled tube (26) acting as the displacement body may be pushed into the hollow piston (22). Figure 4c shows the valve member (23) in oblique view. At the outlet end of the valve member is a radially extending indentation (27) in the form of a recess. Figure 4d shows an alternative to the fourth embodiment in longitudinal section, viewed obliquely. In the cylinder (l) is the hollow piston (28), optionally with the displacement body (26), with the valve in the closed position. The diameter of the valve member (29) is less than the internal diameter of the hollow piston. Figure 4e shows a longitudinal section, viewed obliquely, through the hollow piston (28) with the shaped outlet end (24) and the encircling constriction (25). At least one indentation (30) in the form o£ a recess is provided on the shaped outlet end (24), Instead of the indentation there may be a convexity. Figure 4f shows the valve member (29) in oblique view. In this case, the valve member is a straight cylinder with no recesses. Figure 5 shows the fifth embodiment of the device according to the invention for producing high pressure in a fluid, in longitudinal section and viewed obliquely. In the cylinder (1) is the hollow piston (3D which contains the displacement body (32) . Mounted on the cylindrically widened inlet end (33) of the hollow piston is the closure member (34) with the depression (35) and bore (36). In the indentation is the guided, axially movable valve member (37) which may be provided at its outlet end with a slot (38) as recess. The embodiments of the device according to the invention for producing high pressure in a fluid shown in Figures 2a to 5 work in exactly the same way as has already been explained with reference to Figure la. Figure 6a shows a longitudinal section through the atomiser with the spring biassed and Figures 6b shows a longitudinal section through the atomiser with the spring released. The upper housing part (51) contains the pump housing (52) on the end of which is mounted the holder (53) for the atomiser nozzle. In the holder is the nozzle member (54) and a filter (55). The hollow piston (57) fixed in the driven flange (56) of the blocking mechanism (57) partly projects into the cylinder of the pump housing. At its end the hollow piston carries the valve member (58). The hollow piston is sealed off by the seal (59) . Inside the upper housing part is the abutment (60) on which the driven flange rests when the spring is released. On the driven flange is the abutment (61) on which the driven flange rests when the spring is biased. After the biassing of the spring, the blocking member (62) moves between the abutment (61) and a support (63) in the upper housing part. The actuating button (64) is connected to the blocking member. The upper-housing part terminates in the mouth piece (6S) and is closed off by the protective cap (66) which can be fitted thereon. The spring housing (67) with compression spring (68) is rotatably mounted on the upper housing part by means of the snapping lug (69) and rotary bearing. The lower housing part (70) is pushed over the spring housing. Inside the spring housing is the replaceable storage container (71) for the fluid (72) which is to be atomised. The storage container is fitted with a stopper (73) through which the hollow piston projects into the storage container and dips its end into the fluid. Mounted in the outer surface of the spring housing is the spindle (74) for the mechanical counter. At: the end of the spindle facing the upper housing part is the drive pinion (75). The slider (76) sits on the spindle. The embodiments shown in the drawings may be varied further. The components may be used together in a manner other than that shown in the drawings. Miniaturised device for producing high pressure for a medicinal atomiser The valve area of a medicinal atomiser according to Figure la consists of a cylinder made of polybutylene-terephthalate with an internal diameter of 1.6 mm and an external diameter of 5 mm. The high pressure chamber is closed off by a nozzle carrier plate. In this plate is a nozzle 20 µm in diameter and the nozzle channel is 2 mm long. A metal hollow piston with an external diameter of 1.59 mm and a bore 0.35 mm in diameter is pushed into the cylinder. The hollow piston can be pushed 50mm into the cylinder and its stroke is 12 mm long. The hollow piston has an encircling turned groove 4 mm wide with a base diameter of 0.75 rmm. The groove is bounded by a 4.0 mm long step with a diameter 1.15 mm. The outer edge of the turned end of the hollow piston is chamfered. The valve member made of polybutylenetereph thalate consists of a 2 mm thick disk 1.59 mm in diameter and 3 snap hooks. Three semi-cylindrical channels 0.4 mm in diameter are provided as recesses on the outer surface of the disk. The snap hooks project 6 mm from the disk and the inner edge of the hooks is 4,2 mm away from the disk. The valve member may thus be moved axially 0.2 mm relative to the hollow piston. The delivery volume is 23.4 mm3. The pressure in the fluid is about 32 MPa (320 bar). This atomiser is used to atomise or nebulize liquid Pharmaceuticals for medicinal aerosol therapy. The atomiser delivers the drug in the required dose on each actuation. Example 2: Miniaturised device for producing high pressure for a cosmetic atomiser The valve area of a cosmetic atomiser corresponding to Figure 3a consists of a cylinder of polyetherether-ketone with an internal diameter of 2.5 mm and an outer diameter of 8 mm. The high pressure chamber is closed off by a nozzle carrier plate. In this plate is a nozzle 25 µm in diameter with a nozzle channel 2 mm long. A hollow piston of reinforced plastics with an. external diameter of 2.48 mm and a bore 0.5 mm in diameter is pushed into the cylinder. The hollow piston can be pushed 4S mm into the cylinder and its stroke is 24 mm. The hollow piston is drilled out to art internal diameter of 1.85 mm over a length of 5.0 mm at; its outlet end. The base of the drilled-out chamber it the hollow piston is chamfered. The outlet end of the hollow piston is thermally deformed. The valve member is a cylinder of polypropylene which is 3.0 mm high and 1,6 mm in diameter. Four stepped channels are provided as recesses in the outer surface. The valve member can be displaced axially about 0.5 mm inside the hollow piston. The delivery volume is about 116 mm3. The pressure in the fluid is about 3 MPa (30 bar). This atomiser is used to atomise a hair spray. WE CLAIM: 1. Miniaturised device for producing high pressure in a fluid, comprising a piston which is movable in a cylinder (1), a high pressure chamber (4) which is located in front of the piston inside the cylinder, and a valve, characterised by a cylindrical hollow piston, a valve member which is guided by the hollow piston and is . mounted to be axially movable against the hollow piston, a stop means; on the hollow piston which holds the valve member together with the hollow piston, and a defined sealing surface at the inlet end of the valve member. 2. Device as claimed in claim 1, wherein a cylindrical hollow piston (2) with a stop (8) on the outside of the hollow piston in the region of its outlet end, a cylindrical valve member (3) which is guided and mounted to be axially movable directly at the outlet end of the hollow piston, a plurality of undercut snap hooks (6) mounted on the valve member, and a defined sealing surface at the inlet end of the valve member on the flat outlet end of the hollow piston. 3. Device as claimed in claims 1 and 2, wherein an encircling, preferably turned or shaped groove (5) or a shaped taper with an encircling, outwardly funnel-shaped edge as the stop means at the outlet end of the hollow piston, the external diameter of the hollow piston at its end being greater than the base diameter of the groove or the external diameter of the taper and less than the diameter of the cylinder, or several, preferably two, diamterically opposite points at the outlet end of the hollow piston with flattened surfaces and a step acting as stop means. 4. Device as claimed in claim 1, wherein a hollow piston (11) having an inwardly shaped edge at the outlet end of the hollow piston to act as stop means (12), a cylindrical valve member (13) which is guided and mounted in axially movable manner directly in front of the outlet end of the hollow piston, a coaxial undercut peg (14) on the valve member, and a defined sealing surface which rests on the shaped edge at the outlet end of the hollow piston. 5. Device as claimed in claims 1, 2 and 4 having a cylindrical valve member (3,13) the diameter of which is less than the internal diameter of the cylinder or a cylindrical valve member (3,13) the diameter of which is equal to the internal diameter of the cylinder, and at least one channel (9} extending in the axial direction of the valve member, preferably on the outer surfaces of the valve member. 6. Device as claimed in claim 1, having a cylindrical hollow piston (17) having a widened portion at one end, the inner diameter of which is greater than the inner diameter in the remainder of the hollow piston, an inwardly shaped edge of the hollow piston, a valve member which is guided and mounted in axially movable manner inside the hollow piston in the widened portion thereof, the maximum diameter of the valve member being less than the internal diameter of the hollow piston in its widened portion and greater than the internal diameter in the remainder of the hollow piston, at least one recess in the region of the outlet end of the valve member, a defined sealing surface located inside the hollow piston at the inlet end of the valve member. 7. Device as claimed in claim 6, wherein a cylindrical hollow piston (17) having a widened portion (20) at the outlet end of the hollow piston, an inwardly shaped edge at the outlet end of the hollow piston as a stop means (19), at least one recess (21) in the valve member at the outlet end thereof, or at least one recess in the stop means of the hollow piston. 8. Device as claimed in claim 6, having a cylindrical hollow piston (17) having a widened portion at the inlet end of the hollow piston, an inwardly shaped edge at the inlet end of the hollow piston as a defined sealing surface, a stop means at the outlet end of the widened portion of the hollow piston, at least one recess in the valve member at the outlet end thereof, or at least one recess in the stop means of the hollow piston. 9. Device as claimed in claim 1, wherein a cylindrical hollow piston (22) having an inwardly shaped edge at one end of the hollow piston, an encircling constriction near the shaped edge of the hollow piston, a valve member which is guided and mounted in axially movable manner inside the hollow piston between the shaped edge and the encircling constriction, the maximum diameter of the valve member being less than the internal diameter of the hollow piston, a recess in the region of the outlet end of the valve member, a defined sealing surface which is located inside the hollow piston at the inlet end of the valve member. 10. Device as claimed in claim 9, having a cylindrical hollow piston (22,28) having an inwardly shaped edge at the outlet end of the hollow piston as a stop means (24), an encircling constriction (25) in the region of the shaped edge at the outlet end of the hollow piston, at least one recess (27), in the valve member (23) at the outlet end thereof, or at least one recess (30) in the stop means (24) of the hollow piston. 11. Device as claimed in claim 9, having a cylindrical hollow piston (22) having an inwardly shaped edge at the inlet end of the hollow piston as a defined sealing surface, an encircling constriction in the vicinity of the shaped edge at the inlet end of the hollow piston as a stop means, at least one recess in the valve member at the outlet end thereof, or at least one recess in the stop means of the hollow piston. 12. Device as claimed in claim 1, having a cylindrical hollow piston, a first encircling constriction at a spacing from the outlet end of the hollow piston as a stop means, a second encircling constriction between the first constriction and the inlet end of the hollow piston as a defined sealing surface, a valve member which is guided and mounted in axially movable manner between the two constrictions. 13. Device as claimed in claims 1, 6 and 12, wherein a cylindrical valve member having at least one recess in the valve member at the outlet end thereof, or a preferably cylindrical valve member and at least one recess in the stop means of the hollow piston. 14. Device as claimed in claims 1, 9 and 12 wherein a displacement body (26) having an axially extending channel, which is arranged in the inlet end of the hollow piston and fixedly connected to the hollow piston and preferably extends as far as the encircling constriction which is closest to the inlet end of the hollow piston. 15. Device as claimed in claims 1, 9 and 12 wherein a displacement body having an axially extending channel, which is mounted in the outlet end of the hollow piston and is fixedly connected to the hollow piston and preferably extends as far as the encircling constriction which is closest to the outlet end of the hollow piston. 16. Device as claimed in claim 1, having a cylindrical hollow piston (31) with a widened portion (33) at the entry end and optionally a tube (32) as the displacement body in the unwidened part of the hollow piston, a closure member (34) connected to the widened end of the hollow piston and containing a flat or conical depression (35) with a bore (36), a valve member (37) which is guided and mounted in axially movable manner in the depression, and which is optionally provided at the outlet end with a slot (38) as recess or a notch, a stop means in the region of the outlet end of the valve member, and a defined sealing surface at the inlet end of the valve member. 17. Atomiser for atomising a fluid, utilizing the miniatmized device an claimed in claim1 consisting of an upper housing part (51), a lower housing part (70), a spring housing (67), a spring (68), a pump housing (52), a nozzle, a blocking mechanism and a storage containing (71) having, a pump housing (52) fixed in the upper housing part (51) and having at one end a nozzle member (54) with the nozzle, a hollow piston (57) with a valve member (58), a driven flange (56) in which the hollow piston (57) is secured and which is located in the upper housing part (51), a blocking mechanism arranged in the upper housing part (51), the spring housing (67) with the spring (68) located therein, which is rotatably mounted on the upper housing part by means of a rotary bearing, a lower housing part (70) which can be fitted onto the spring housing (67) in the axial direction. 8. Atomiser for atomising a fluid as claimed in claim 17 having which projects partly into the cylinder of the pump housing (52) and is mounted in axially movable manner in the cylinder, a driven flange (56) in which the hollow piston (57) is secured and which is located in the upper housing part (51), a blocking mechanism arranged in the upper housing part (51), a spring housing (67) with the spring (68) located therein, which is rotatably mounted on the upper housing part by means of a rotary bearing, a lower housing part (70) which can be fitted onto the spring housing (67) in the axial direction. 19. Atomiser as claimed in any one of claims 17 and 18, having a blocking mechanism in the form of a helical thrust gear, with a blocking member (62) arranged in annular configuration with engaging locking surfaces and an actuating button (64), 20. Atomiser as claimed in any one of claims 17 to 20, having a mechanical counter having a spindle (74) and a slider (76), which is mounted on the spring housing (67) in the region of the outer surface, and the axis of which runs parallel to the axis of the spring housing (67). 21. Atomiser as claimed in any one of claims 17 to 20, having a nozzle member (54) consisting of two glass and/or silicon plates firmly joined together, at least one plate having one or more microstructured channels which connect the nozzle inlet end to the nozzle outlet end, and the nozzle outlet end has at least one opening less than or equal to 10 µm in size. 22. Atomiser as claimed in claim 21, having a nozzle member (54) having at least two nozzle openings at the outlet end, the directions of spraying being inclined relative to one another and meeting in the vicinity of the nozzle openings. 23. Atomiser as claimed in any one of claims 17 to 22, having a non return valve mounted in the pump housing (52) between the nozzle opening and high pressure chamber of the cylinder. 24. Atomiser as claimed in any one of claims 17 to 23, having a hollow piston (57) which exerts a pressure of 5 to 60 Mpa (about 50 to 600 bar) on the fluid at its end facing the nozzle (high pressure end) at the moment of actuation of the spring (68). 25. Atomiser as claimed in claim 24, having a hollow piston (57) which exerts a pressure of 10 to 60 Mpa (about 100 to 600 bar) on the fluid at its end facing the nozzle (high pressure end) at the moment of actuation of the spring (68). 26. Atomiser as claimed in any one of claims 17 to 25, having a replaceable storage container (71) for the fluid (72) arranged in the lower housing part. 27. Storage container for a fluid, containing a pharmaceutical composition, for use in an atomiser as claimed in claim claims 17 to 26. 28. Atomiser as claimed in any one of claims 17 to 27 whenever used for producing medicinal aerosols without propellant gas. 29. Storage container as claimed in claim 27, containing a pharmaceutically acceptable solution of a medicament selected from the group comprising; berotec, berodual, flunisolide, atrovent, salbutanol, budesonide, combivent, tiotropium, oxivent and suitable peptides. 30. Miniaturised device for producing high pressure substantially as hereinbefore described with reference to the accompanying drawings. 31. Atomiser for atomising a fluid substantially as hereinbefore described with reference to the accompanying drawings. 32. Storage container for a fluid substantially as hereinbefore described with reference to the accompanying drawings.

Full Text

The present invention relates to a miniaturised device for producing high pressure in a fluid.
Tne invention relates to a device for producing high pressure in a fluid. It consists of a piston which is movable in a cylinder, and a valve, both of miniaturised construction. The invention further relates to a high pressure atomiser which contains this device, and the use thereof, preferably for medicinal purposes.
The aim of the invention is to enable a device of this kind and the atomiser containing the device to be made simpler in design and cheaper to produce.
In liquid chromatography (HPLC), for example, generally relatively small quantities of liquid are conveyed at high pressure through the separating column. Moreover, in medicinal aerosol therapy, aerosols are used, by atomising or nebulising liquid drugs for treating diseases of the respiratory tract in humans or for treating asthmatic conditions. Here again, a high pressure is required in a, generally relatively small, quantity of fluid, in order to produce the small droplet size needed for the aerosol. In the nebulizer according to WO-91/14458 a given volume of; a fluid is sprayed through a nozzle with a small aperture .under a pressure of between 5 and 40 MPa {about 50 to 400 bar) to produce an aerosol.
The aim of the invention is to provide a device suitable for producing high pressure in a fluid and. an atomiser containing this device, the device for producing high, pressure being easier to produce and optimally adapted to its function, preferably in a high pressure atomiser.
The first part of this problem is solved according to the invention by a devic for producing high pressure in a fluid, of miniaturised constrution, consisting of
a piston which is movable in a cylinder, a high pressure chamber located in front of the piston inside the cylinder, and a valve, characterised by:
a cylindrical hollow piston,
a valve member which is guided by the hollow piston and: is mounted so as to be axially movable against the hollow piston,
a stop means on the hollow piston which holds the valve member together with the hollow piston, and
a defined sealing surface at the inlet end of the valve member.
In the specification which follows, the terms inlet and outlet side or inlet and outlet end are used in relation to the main direction of flow of the fluid within the device.
The valve member is somewhat displaceable against the hollow piston but it moves substantially with the hollow piston.
The valve member is preferably uniaxially rotationally symmetrical in shape, e.g. it is a circular cylinder or a frustum. Its cross-section is somewhat smaller than the cross- sect ion of the chamber in which Che valve member is movably mounted. This is achieved by means of one or more channels preferably extending in the outer surface of the cylindrical valve member, or by a somewhat smaller diameter of the valve member in relation to the diameter of the chamber in which the valve member is movably mounted.
The valve member is guided in the chamber in which it is movably mounted; the cylindrical valve member can rotate about its axis as required, but its axis always remains parallel to the axis of the hollow piston. This produces a defined sealing surface at the inlet of the valve member.
The distance over which the valve member can travel relative to the hollow piston is limited by a stop or stop means which holds the movable valve member together with the hollow piston.
In the region of the outlet end of the valve member there is at least one recess to enable the fluid to flow through between the stop and the valve member when the valve is open. The or each recess is located either in the valve member at the outlet end thereof or in the stop in the hollow piston.
In the position where the valve member abuts on the stop of the hollow piston, the valve is opened. In the position where the valve member abuts on the defined sealing surface, the valve is closed.
The valve member arranged inside the hollow piston has virtually no friction against the inner wall of the hollow piston. The valve member arranged directly in front of the end of the hollow piston may possibly rub against the wall of the cylinder. In this case, the valve is actively closed and opened as the hollow piston moves, on account of the friction between the valve member and the cylinder wall.
The cylinder preferably consists of plastics and the hollow piston of metal or plastics. The material for the valve member is selected, in terms of its hardness, to complement the hardness of the material for the hollow piston and may be metal, ceramics, glass, gemstone, plastics or elastomer. The valve member is preferably manufactured in one piece.
When the fluid is sucked in, the high pressure chamber is connected to the fluid supply by means of the channels in the valve member. During the intake stroke of the hollow piston the fluid flows through the hollow piston and past the valve member into the high pressure chamber of the cylinder. During the exhaust stroke of the hollow piston the valve is sealed in high pressure tight manner against the defined sealing surface of the valve member.
The device according to the invention for producing high pressure in a fluid is connected to the fluid supply at its inlet end. The high pressure chamber is connected to another device into which or through which
the fluid is conveyed under high pressure. The hollow piston or the cylinder is attached to a drive which brings about relative movement between the hollow piston and cylinder and which applies the force required to generate the high pressure.
In the first embodiment, the cylindrical valve member may be guided and mounted in axially mcvable manner directly in front of the end of the hollow piston, the diameter of the valve member being substantially equal to the internal diameter of the cylinder. On the outside, near its outlet end, the hollow piston has an encircling, preferably turned or shaped groove as a stop member, into which a plurality of snap hooks mounted on the valve member engage. Instead of the groove, the hollow piston may have at its outlet end a shaped taper with an encircling, outwardly funnel-shaped edge. The outer diameter of the hollow piston at its outlet end is greater than the base diameter of the groove and less than the diameter of the cylinder. Instead of the encircling groove, the outlet end of the hollow piston may be provided on the outside, at several, preferably 2 diametrically opposed points, with flattened areas which form a step to act as a stop means. The flat end of the hollow piston is the defined sealing surface. The outer edge at the end of: the hollow piston may be chamfered.
In the second embodiment, the cylindrical valve member may be guided and movably mounted directly in front of the end of the hollow piston, the diameter of the valve member being substantially equal to the internal diameter of the cylinder. The end of the hollow piston is shaped inwardly and acts as a stop means. On the valve member is mounted a coaxial, undercut, mushroom-shaped peg the snap hooks of which engage behind the shaped edge of the hollow piston. The defined sealing surface rests on the outside of the piston at the shaped edge.
In the third embodiment, the preferably cylindrical
valve member may be mounted so as to be fully movable inside the hollow piston. The outlet end of the hollow piston has an internal diameter greater than the internal diameter of the remainder of the hollow piston. The length of this widened portion of the hollow piston is somewhat greater than the length of the valve member. The diameter of the valve member is substantially equal to the inner diameter at the widened end of the hollow piston. The outlet end of the hollow piston is shaped inwardly either over its entire periphery or over a part of its periphery and acts as a stop which holds the valve member inside the hollow piston. The base of the widened portion which forms the defined sealing surface may be flat or conical. The recess in the valve member may, for example, take the form of a stepped channel. The recess in the stop may be constructed, for example, as an indentation.
In a variant of this embodiment, the valve member may be arranged totally inside the hollow piston at the inlet end thereof. The stop will then be located at the outlet end of the widened portion and the defined sealing surface will then be on the shaped edge at the inlet end of the hollow piston.
In the fourth embodiment, the hollow piston consists of a thin-walled tube which is shaped at its end projecting into the cylinder and is provided with an encircling constriction at the end of the space allowed for the valve member. The cylindrical valve member is guided and movably mounted in the space between the shaped edge and the encircling constriction. Another thick-walled tube may be pushed into the inlet end of the hollow piston, its outer diameter being equal to the inner diameter of the hollow piston, and this thick-walled tube further being fixedly connected to the hollow piston and preferably extending approximately up to the encircling constriction in the hollow piston. The thick-walled tube acts as a displacement member and makes it easier for the fluid to be sucked into the high
pressure chamber virtually without pressure. The thick-walled tube is preferably made of plastics.
In a variant of this embodiment, the valve member may be mounted fully inside the hollow piston at the inlet end thereof, The stop is then located at the encircling constriction and the defined sealing surface is located at the shaped edge at the inlet end of the hollow piston.
In the fifth embodiment, the hollow piston comprises a thin-walled tube which contains a thick-walled tube the outer diameter of which is equal to the inner diameter of the hollow piston, and which is fixedly connected to the hollow piston. The thick-walled tube functions as a displacement body and makes it easier for the fluid to be sucked in virtually without pressure.
The inlet end of the hollow piston is widened. At the widened end, the hollow piston is fixedly connected to a closure member the outer diameter of which is greater than the outer diameter of the widened inlet end of the hollow piston. The closure member contains a depression which is open on its side facing the widened end of the hollow piston. In the base of the depression is an opening acting as an inlet for the fluid. The base of the depression may be conical or flat; it forms the defined sealing surface.
The valve member is arranged in the depression, in the closure member; it. is guided so as to be axially movable in the depression. The external diameter of the valve member is smaller than the internal diameter of the depression, but preferably greater than the internal diameter of the hollow piston in that part of it which projects into the cylinder. The valve member may contain, at its outlet end, at least one recess through which the fluid flows into the high pressure chamber during the intake stroke of the hollow piston.
The stop for the valve member is preferably the end of the displacement body which projects into the widened
portion or the hollow piston, or if the end of the displacement body is located in the unwidened portion of the hollow piston - the transition from the unwidened portion of the hollow piston into the widened inlet end thereof.
The hollow piston, with the widened inlet end preferably consists of metal. The displacement body and closure member are preferably made of plastics. The valve member may be made of plastics or metal.
Of particular significance is the use of the device according to the invention for producing high pressure in a fluid in an atomiser (nebulizer) for propellent-free spraying of the fluid.
The second part of the objective is achieved according to the invention by an atomiser for spraying a fluid, consisting of an upper housing part, a pump housing, a nozzle, a blocking mechanism, a spring housing, a spring and a supply container, characterised by
a pump housing fixed in the upper housing part, which has at one end a nozzle member with the nozzle,
a hollow piston with valve member,
a drive flange in which the hollow piston is secured and which is located in the upper housing part,
a blocking mechanism located in the upper housing part,
a spring housing with the spring located therein, which is rotatably mounted by means of a rotary bearing on the upper housing part,
a lower housing part which is fitted onto the spring housing in the axial direction.
The hollow piston with valve member corresponds to one of the devices according to the invention mentioned hereinbefore. It projects partially into the cylinder of the pump housing and is mounted in axially movable manner in the cylinder. The hollow piston with valve member exerts a pressure of 5 to 60 MPa (about 50 to 600 bar) , preferably 10 to 60 MPa (about 100 to 600 bar) on
the fluid at its high pressure end at the moment of release of the spring.
The nozzle in the nozzle member is preferably microstructured, ie. produced by microtechnology. Microstructured nozzle members are disclosed, for
example, in #0-94/07607; we hereby refer to the contents of this specification.
The nozzle member consists, for example, of two plates of glass and/or silicon firmly joined together, of which at least one plate has one or more microstructured channels which connect the nozzle inlet end to the nozzle outlet end. At the nozzle outlet end is at least one circular or non-circular opening less than or equal to 10µm in size.
The directions of. spraying of the nozzles in the nozzle member may run parallel to one another or may be inclined relative to one another. In a nozzles member having at least two nozzle openings at the outlet end, the directions of spray may be inclined relative to one another at an angle from 20 to 160", preferably at an angle from 60 to 150°. The directions of spraying meet in the vicinity of the nozzle openings.
In the pump housing, a non-return valve with or without spring bias may be provided between the nozzle opening and the high pressure chamber of the cylinder. This non-return valve closes off the high pressure chamber in the resting state of the atomiser, protects the fluid from the entrance of air and may if necessary prevent volatile components of the fluid from evaporating out of the pump housing. The non-return valve opens automatically as soon as the pressure of the fluid in the high pressure chamber exceeds a minimum value and the current of fluid is created; it closes automatically as soon as the current of fluid is
exhausted. The non-return valve may be, for example, a
t ball valve. It may also consist of a flexible plate
which is clamped on one side and rests like a flap on the outlet end of the high pressure chamber. In another
embodiment it may consist of a disk of preferably flexible material, clamped all the way round, pierced by a pin. The pierced hole allows the current of fluid to pass through to the nozzle as soon as the pressure in the fluid exceeds a minimum value. After the current of fluid is exhausted, the pin hole closes up again.
The valve member is preferably mounted at the end of the hollow piston facing the nozzle member.
The blocking mechanism contains a spring, preferably a cylindrical helical compression spring, as a store for mechanical energy. The spring acts on the driven flange as a jumping member the movement of which is determined by the position of a blocking member. The path of travel of the driven flange is precisely defined by an upper and lower stop. The spring is preferably tensioned by an external torque via a power stepping-up gear, eg. a helical thrust gear, which is generated as the upper housing part rotates counter to the spring housing in the lower housing part. In this case, the upper housing part and the driven flange contain a single or multiple wedge gear.
The blocking member with engaging blocking surfaces is arranged -in an annular configuration around the driven flange. It consists, for example, of a. plastics or metal ring which is inherently radially resiliently deformable. The ring is arranged in a plane at right angles to the atomiser axis. After the biassing of the spring, the blocking surfaces of the blocking member move into the path of the driven flange and prevent the spring from being released. The blocking member is actuated by a button. The actuating button is connected or coupled to the blocking member. In order to actuate the blocking mechanism the actuating button is pushed parallel to the plane of the ring, preferably into the atomiser; the deformable ring is thereby deformed in the plane of the ring.
The atomiser optionally contains a mechanical counter consisting of a spindle with rotational barrier
which is mounted on the spring housing. The axis of the spindle extends in the region of the outer surface parallel to the axis of the atomiser. The spindle is mounted, in the region of its ends, by means of a rotary bearing on the spring housing. The spindle has teeth at the end closest to the upper housing part. On the edge of the upper housing part is at least one cam which, engages in the teeth at the end of the spindle when the two housing parts are rotated relative to one another. A slider with rotation prevention means sits on the spindle.
The lower housing part is pushed axially over the spring housing and covers the mounting, the drive of the spindle and the storage container for the fluid. The position of the slider is visible through a recess in the lower housing part and can be read off on a scale, eg. on the lower housing part.
When the atomiser is actuated the upper housing part is rotated relative to the lower housing part, the lower housing part carrying the spring housing with it. The spring meanwhile is compressed and biassed by means of the helical thrust gear, and the blocking mechanism engages automatically. The angle of rotation is preferably a whole-number fraction of 360º, eg. 180º. At the same time as the spring is biassed, the driven part in the upper housing part is moved a certain distance, the hollow piston is retracted inside the cylinder in the pump housing, as a result of which some of: the fluid is sucked out of the storage container into the high pressure chamber in front of the nozzle.
By means of the gears, which consist of the teeth on one end of the spindle and the or each cam on the edge of the upper housing part, the relative movement of the two housing parts is picked up and converted into a rotary movement of the spindle and displacement of the slider on the spindle. On each actuation of the atomiser, the slider is moved a certain distance along the spindle.
The position of the slider indicates what proportion of the fluid to be atomised has already been taken from the storage container and how much is still available. The slider on the spindle can be reset if necessary by means of a resetting lug.
If desired, a plurality of replaceable storage containers holding the fluid which is to be atomised can be inserted into the atomiser one after another and used. The storage container is not pressurised or substantially-not pressurised. The pressure of the fluid in the storage container is in any case substantially lower than the pressure generated in the high pressure chamber by the mechanically operated atomiser. The storage container contains, for example, a fluid containing a drug.
The atomising process is started by gently pressing the actuating button. The blocking mechanism then opens up a path for the driven part to move. The biassed spring pushes the piston into the cylinder of the pump housing. The fluid leaves the nozzle of the atomiser in spray form.
The components of the atomiser are made of a material which is suitable for the function. The housing of the atomiser and, insofar as function allows, other parts are preferably made of plastics, eg. by injection moulding. For medicinal purposes, physiologically acceptable materials are used.
The atomiser according to the invention is used, for example, for propellant-free production of medicinal aerosols. An inhalable aerosol with an average particle size of about 5 µm can be produced thereby.
The following active substances are mentioned by way of example of pharmaceutical compositions in the form of aqueous or ethanolic solutions, depending ,cn the solubility of the active substance: berotec, berodual, flunisolide, atrovent, salbutamol, budesonide, combivent, tiotropium, oxivent and suitable peptides.
The solutions may also contain pharmaceutically
acceptable excipients..
The device according to the invention for producing
high pressure in a fluid and the atomiser containing
this device have the following advantages:
The device contains a valve which operates without
any auxiliary force (produced by a spring) and
closes as a result of the flow resistance of the
fluid on the valve member or as a result of the
friction on the cylinder wall.
The valve is tight against a pressure generally
above 3 MPa (30 bar) .
The valve member is made in one piece; it is easy
to manufacture and assemble.
The valve closes very rapidly owing to the short
distance travelled by the valve member to reach the
defined sealing surface.
The valve has a high sealing action.
As a result of the guiding of the uniaxially
rotationally symmetrical valve member, a defined
sealing surface is produced which is high pressure
tight through a very large number of cycles of
movement of the hollow piston.
The dead space of the high pressure chamber can be
kept extremely small.
The atomiser can be operated safely and easily even
by untrained persons, both to bias the spring and
to actuate the atomising process.
The atomiser works without propellant gas and is
therefore environmentally friendly.
The storage container for the fluid is not
pressurised or substantially not pressurised.
The movement of the blocking member is
automatically coupled, by a simple method, to the
rotary movement for Massing the spring.
In a preferred embodiment the atomiser consists of
low-wear purely mechanical components and operates
reliably over long periods.
Owing to the defined abutments for the driven part
the metering of the fluid is very accurate.
The atomiser can be manufactured cheaply and
assembled easily.
The mechanical counter is automatically advanced as
the atomiser is actuated; it is uncritical of
tolerance, easy to assemble and operates safely and
reliably.
The counter is inaccessible when the atomiser is
used properly and cannot be falsified by accident.
The counter can be adapted to any number of
releases of fluid from the storage container and to
different overall numbers of storage containers to
be used with one atomiser.
The counter is integrated in the atomiser and does
not take up any additional space.
No substances can pass from the counter into the
substance which is to be atomised.
The device according to the invention for producing high pressure in a fluid and the atomiser containing this device are explained more fully with reference to Figures l to 6.
Figure la shows a longitudinal section, viewed obliquely, through the first embodiment of the device according to the invention for producing high pressure in a fluid. In the cylinder (1) is the hollow piston (2) with the coaxial bore (7) and the valve member (3) in the partly open position of the valve. Between the bottom of the valve member (3) and the end of the cylinder is the high pressure chamber (4). The high pressure chamber is closed off by another component (not shown). Mounted on the hollow piston, outside the cylinder, is a device (non shown) by means of which the hollow piston can be displaced inside the cylinder.
Figure ib shows the hollow piston (2) viewed obliquely. The end of the hollow piston facing the valve member is provided with a groove (5) which is bounded, at its end facing the valve member, by a step (8) the diameter of which is less than the external
diameter of the hollow piston (2) and greater than the base diameter of the groove. The front edge at the end of the hollow piston may be chamfered.
Figure 1c shows the valve Timber (3) viewed obliquely, it has, for example, three channels (9) on its outer surface. Mounted on the valve member (3), on its side facing the hollow piston, are, for example, three snap hooks (6) the width of which, in the direction of the circumference of the valve member, is less than a third of this circumference. The snap hooks
(6) are shorter in the axial direction than the length
of the, for example, gxooved end of the hollow piston.
During assembly, the valve member {3) is placed on the end of the hollow piston (2), and the hooks (10) slide into the groove. The hollow piston together with the valve member is then pushed into the cylinder.
When the valve is open, the inner edge o£ the hooks (10) abut on the step (8). When the valve is closed, the base of the valve member (3) facing the hollow piston fits tightly on the end of the hollow piston (2) which acts as the defined sealing surface.
In order to take in the fluid, the hollow piston is
lifted partly out of the cylinder, whereupon the valve
automatically opens. The fluid flows through the bore
(7) in the hollow piston and past the valve member into
the high pressure chamber (4) . In order to expel the
fluid, the hollow piston (2) is pushed into the cylinder
(1), whereupon the valve closes automatically, virtually
instantly, and high pressure is generated in the fluid.
Figure 2a shows the second embodiment of the device according to the invention for producing high pressure in a fluid as a longitudinal section viewed obliquely. In the cylinder (1) is the hollow piston (11) and the valve member (13) in the partly open position of the valve.
Figure 2b shows a longitudinal section through the" hollow piston (11) with the shaped outlet end (12) of the hollow piston. The displacement body (26) may be
located in the hollow piston.
Figure 2c shows the valve member (13) as a longitudinal section viewed obliquely. Mounted on the valve member is a coaxial, undercut peg (14) the projecting end of which engages behind the shaped edge (12) of the hollow piston. The end (15) of the peg facing the hollow piston may be chamfered. The peg may have an indentation (16) extending in the axial direction so that the peg can be pushed into the shaped end of the hollow piston, thereby engaging behind the shaped edge.
Figure 3a shows the third embodiment of the device according to the invention for producing high pressure in a fluid in longitudinal section viewed obliquely, in the cylinder (1) is the hollow piston (17) and the valve member (18) in the closed position of the valve.
Figure 3b shows a longitudinal section viewed obliquely through the hollow piston (17) with the shaped end (19) . At the outlet end of the hollow piston IB the widened portion (20) in which the valve member (18) is guided and mounted in axially movable manner. The inlet end of the widened portion (20) is chamfered or flat.
Figure 3c shows the cylindrical valve member (18) in longitudinal section viewed obliquely. Both bases of the valve member are planar and are located perpendicularly to the axis of the valve member. The valve member (18) contains, for example, four stepped channels (21) on its outer surface. The edge of the valve member (18) which abuts on the inclined base of the hollow chamber (20) may be chamfered.
The diameter of the valve member (18) is less than the diameter of the widened portion (20) so that the valve member (18) can move virtually without friction in the widened portion (20).
For assembly, the valve member (18) is pushed into the widened portion (20) before the outlet end (19) of the hollow piston is shaped.
Figure 4a shows the fourth embodiment of toe device
according to the invention for producing high pressure in a fluid in longitudinal section viewed obliquely. In the cylinder (1) are the hollow piston (22) and the valve member (23) in the closed position of the valve. The diameter of the valve member is Icoo than the inner
diameter of the hollow piston.
Figure 4b shows a longitudinal section, viewed obliquely, through the hollow piston (22) with the shaped outlet end (24) and the encircling constriction (25). The thick-walled tube (26) acting as the displacement body may be pushed into the hollow piston (22).
Figure 4c shows the valve member (23) in oblique view. At the outlet end of the valve member is a radially extending indentation (27) in the form of a recess.
Figure 4d shows an alternative to the fourth embodiment in longitudinal section, viewed obliquely. In the cylinder (l) is the hollow piston (28), optionally with the displacement body (26), with the valve in the closed position. The diameter of the valve member (29) is less than the internal diameter of the hollow piston.
Figure 4e shows a longitudinal section, viewed obliquely, through the hollow piston (28) with the shaped outlet end (24) and the encircling constriction (25). At least one indentation (30) in the form o£ a recess is provided on the shaped outlet end (24), Instead of the indentation there may be a convexity.
Figure 4f shows the valve member (29) in oblique view. In this case, the valve member is a straight cylinder with no recesses.
Figure 5 shows the fifth embodiment of the device according to the invention for producing high pressure in a fluid, in longitudinal section and viewed obliquely. In the cylinder (1) is the hollow piston (3D which contains the displacement body (32) . Mounted on the cylindrically widened inlet end (33) of the
hollow piston is the closure member (34) with the depression (35) and bore (36). In the indentation is the guided, axially movable valve member (37) which may be provided at its outlet end with a slot (38) as recess.
The embodiments of the device according to the invention for producing high pressure in a fluid shown in Figures 2a to 5 work in exactly the same way as has already been explained with reference to Figure la.
Figure 6a shows a longitudinal section through the atomiser with the spring biassed and Figures 6b shows a longitudinal section through the atomiser with the spring released.
The upper housing part (51) contains the pump housing (52) on the end of which is mounted the holder (53) for the atomiser nozzle. In the holder is the nozzle member (54) and a filter (55). The hollow piston (57) fixed in the driven flange (56) of the blocking mechanism (57) partly projects into the cylinder of the pump housing. At its end the hollow piston carries the valve member (58). The hollow piston is sealed off by the seal (59) . Inside the upper housing part is the abutment (60) on which the driven flange rests when the spring is released. On the driven flange is the abutment (61) on which the driven flange rests when the spring is biased. After the biassing of the spring, the blocking member (62) moves between the abutment (61) and a support (63) in the upper housing part. The actuating button (64) is connected to the blocking member. The upper-housing part terminates in the mouth piece (6S) and is closed off by the protective cap (66) which can be fitted thereon.
The spring housing (67) with compression spring (68) is rotatably mounted on the upper housing part by means of the snapping lug (69) and rotary bearing. The lower housing part (70) is pushed over the spring housing. Inside the spring housing is the replaceable storage container (71) for the fluid (72) which is to be
atomised. The storage container is fitted with a stopper (73) through which the hollow piston projects into the storage container and dips its end into the fluid.
Mounted in the outer surface of the spring housing is the spindle (74) for the mechanical counter. At: the end of the spindle facing the upper housing part is the drive pinion (75). The slider (76) sits on the spindle.
The embodiments shown in the drawings may be varied further. The components may be used together in a manner other than that shown in the drawings.
Miniaturised device for producing high pressure for a medicinal atomiser
The valve area of a medicinal atomiser according to Figure la consists of a cylinder made of polybutylene-terephthalate with an internal diameter of 1.6 mm and an external diameter of 5 mm. The high pressure chamber is closed off by a nozzle carrier plate. In this plate is a nozzle 20 µm in diameter and the nozzle channel is 2 mm long.
A metal hollow piston with an external diameter of 1.59 mm and a bore 0.35 mm in diameter is pushed into the cylinder. The hollow piston can be pushed 50mm into the cylinder and its stroke is 12 mm long. The hollow piston has an encircling turned groove 4 mm wide with a base diameter of 0.75 rmm. The groove is bounded by a 4.0 mm long step with a diameter 1.15 mm. The outer edge of the turned end of the hollow piston is chamfered.
The valve member made of polybutylenetereph thalate consists of a 2 mm thick disk 1.59 mm in diameter and 3 snap hooks. Three semi-cylindrical channels 0.4 mm in diameter are provided as recesses on the outer surface of the disk. The snap hooks project 6 mm from the disk and the inner edge of the hooks is 4,2 mm away from the disk. The valve member may thus be moved axially 0.2 mm relative to the hollow piston.
The delivery volume is 23.4 mm3. The pressure in the fluid is about 32 MPa (320 bar).
This atomiser is used to atomise or nebulize liquid Pharmaceuticals for medicinal aerosol therapy. The atomiser delivers the drug in the required dose on each actuation.
Example 2: Miniaturised device for producing high pressure for a cosmetic atomiser
The valve area of a cosmetic atomiser corresponding to Figure 3a consists of a cylinder of polyetherether-ketone with an internal diameter of 2.5 mm and an outer diameter of 8 mm. The high pressure chamber is closed off by a nozzle carrier plate. In this plate is a nozzle 25 µm in diameter with a nozzle channel 2 mm long.
A hollow piston of reinforced plastics with an. external diameter of 2.48 mm and a bore 0.5 mm in diameter is pushed into the cylinder. The hollow piston can be pushed 4S mm into the cylinder and its stroke is 24 mm. The hollow piston is drilled out to art internal diameter of 1.85 mm over a length of 5.0 mm at; its outlet end. The base of the drilled-out chamber it the hollow piston is chamfered. The outlet end of the hollow piston is thermally deformed.
The valve member is a cylinder of polypropylene which is 3.0 mm high and 1,6 mm in diameter. Four stepped channels are provided as recesses in the outer surface. The valve member can be displaced axially about 0.5 mm inside the hollow piston.
The delivery volume is about 116 mm3. The pressure in the fluid is about 3 MPa (30 bar).
This atomiser is used to atomise a hair spray.

WE CLAIM:
1. Miniaturised device for producing high pressure in a fluid, comprising a piston which is movable in a cylinder (1), a high pressure chamber (4) which is located in front of the piston inside the cylinder, and a valve, characterised by a cylindrical hollow piston, a valve member which is guided by the hollow piston and is
. mounted to be axially movable against the hollow piston,
a stop means; on the hollow piston which holds the valve member
together with the hollow piston, and
a defined sealing surface at the inlet end of the valve member.
2. Device as claimed in claim 1, wherein a cylindrical hollow piston (2) with a stop (8) on the outside of the hollow piston in the region of its outlet end, a cylindrical valve member (3) which is guided and mounted
to be axially movable directly at the outlet end of the hollow piston, a plurality of undercut snap hooks (6) mounted on the valve member, and
a defined sealing surface at the inlet end of the valve member on the flat outlet end of the hollow piston.
3. Device as claimed in claims 1 and 2, wherein an encircling,
preferably turned or shaped groove (5) or a shaped taper with an
encircling, outwardly funnel-shaped edge as the stop means at the
outlet end of the hollow piston, the external diameter of the hollow
piston at its end being greater than the base diameter of the groove
or the external diameter of the taper and less than the diameter of
the cylinder, or
several, preferably two, diamterically opposite points at the outlet end of the hollow piston with flattened surfaces and a step acting as stop means.
4. Device as claimed in claim 1, wherein a hollow piston (11) having
an inwardly shaped edge at the outlet end of the hollow piston to
act as stop means (12),
a cylindrical valve member (13) which is guided and mounted in
axially movable manner directly in front of the outlet end of the
hollow piston,
a coaxial undercut peg (14) on the valve member, and
a defined sealing surface which rests on the shaped edge at the
outlet end of the hollow piston.
5. Device as claimed in claims 1, 2 and 4 having
a cylindrical valve member (3,13) the diameter of which is less than the internal diameter of the cylinder or
a cylindrical valve member (3,13) the diameter of which is equal to the internal diameter of the cylinder, and at least one channel (9} extending in the axial direction of the valve member, preferably on the outer surfaces of the valve member.
6. Device as claimed in claim 1, having a cylindrical hollow piston
(17) having a widened portion at one end, the inner diameter of
which is greater than the inner diameter in the remainder of the
hollow piston,
an inwardly shaped edge of the hollow piston,
a valve member which is guided and mounted in axially movable
manner inside the hollow piston in the widened portion thereof,
the maximum diameter of the valve member being less than the
internal diameter of the hollow piston in its widened portion and
greater than the internal diameter in the remainder of the hollow
piston,
at least one recess in the region of the outlet end of the valve
member,
a defined sealing surface located inside the hollow piston at the
inlet end of the valve member.
7. Device as claimed in claim 6, wherein a cylindrical hollow piston
(17) having a widened portion (20) at the outlet end of the hollow
piston,
an inwardly shaped edge at the outlet end of the hollow piston as a
stop means (19),
at least one recess (21) in the valve member at the outlet end
thereof, or
at least one recess in the stop means of the hollow piston.
8. Device as claimed in claim 6, having a cylindrical hollow piston
(17) having a widened portion at the inlet end of the hollow piston,
an inwardly shaped edge at the inlet end of the hollow piston as a
defined sealing surface,
a stop means at the outlet end of the widened portion of the hollow
piston,
at least one recess in the valve member at the outlet end thereof, or
at least one recess in the stop means of the hollow piston.
9. Device as claimed in claim 1, wherein a cylindrical hollow piston
(22) having an inwardly shaped edge at one end of the hollow
piston,
an encircling constriction near the shaped edge of the hollow piston,
a valve member which is guided and mounted in axially movable manner inside the hollow piston between the shaped edge and the encircling constriction, the maximum diameter of the valve member being less than the internal diameter of the hollow piston,
a recess in the region of the outlet end of the valve member,
a defined sealing surface which is located inside the hollow piston
at the inlet end of the valve member.
10. Device as claimed in claim 9, having a cylindrical hollow piston
(22,28) having an inwardly shaped edge at the outlet end of the
hollow piston as a stop means (24),
an encircling constriction (25) in the region of the shaped edge at
the outlet end of the hollow piston,
at least one recess (27), in the valve member (23) at the outlet end
thereof, or
at least one recess (30) in the stop means (24) of the hollow piston.
11. Device as claimed in claim 9, having a cylindrical hollow piston
(22) having an inwardly shaped edge at the inlet end of the hollow
piston as a defined sealing surface,
an encircling constriction in the vicinity of the shaped edge at the inlet end of the hollow piston as a stop means,
at least one recess in the valve member at the outlet end thereof, or at least one recess in the stop means of the hollow piston.
12. Device as claimed in claim 1, having a cylindrical hollow piston,
a first encircling constriction at a spacing from the outlet end of the hollow piston as a stop means,
a second encircling constriction between the first constriction and the inlet end of the hollow piston as a defined sealing surface, a valve member which is guided and mounted in axially movable manner between the two constrictions.
13. Device as claimed in claims 1, 6 and 12, wherein a cylindrical valve member having at least one recess in the valve member at the outlet end thereof, or
a preferably cylindrical valve member and at least one recess in the stop means of the hollow piston.
14. Device as claimed in claims 1, 9 and 12 wherein a displacement body (26) having an axially extending channel, which is arranged in the inlet end of the hollow piston and fixedly connected to the hollow piston and preferably extends as far as the encircling constriction which is closest to the inlet end of the hollow piston.
15. Device as claimed in claims 1, 9 and 12 wherein a displacement body having an axially extending channel, which is mounted in the outlet end of the hollow piston and is fixedly connected to the hollow piston and preferably extends as far as the encircling constriction which is closest to the outlet end of the hollow piston.
16. Device as claimed in claim 1, having a cylindrical hollow piston (31) with a widened portion (33) at the entry end and optionally a tube (32) as the displacement body in the unwidened part of the hollow piston,
a closure member (34) connected to the widened end of the hollow
piston and containing a flat or conical depression (35) with a bore
(36),
a valve member (37) which is guided and mounted in axially
movable manner in the depression, and which is optionally
provided at the outlet end with a slot (38) as recess or a notch,
a stop means in the region of the outlet end of the valve member,
and
a defined sealing surface at the inlet end of the valve member.
17. Atomiser for atomising a fluid, utilizing the miniatmized device
an claimed in claim1 consisting of an upper housing part
(51), a lower housing part (70), a spring housing (67), a spring (68),
a pump housing (52), a nozzle, a blocking mechanism and a storage containing (71) having,
a pump housing (52) fixed in the upper housing part (51) and having at one end a nozzle member (54) with the nozzle, a hollow piston (57) with a valve member (58),
a driven flange (56) in which the hollow piston (57) is secured and which is located in the upper housing part (51),
a blocking mechanism arranged in the upper housing part (51), the spring housing (67) with the spring (68) located therein, which is rotatably mounted on the upper housing part by means of a rotary bearing,
a lower housing part (70) which can be fitted onto the spring housing (67) in the axial direction.
8. Atomiser for atomising a fluid as claimed in claim 17 having
which projects partly into the cylinder of the pump
housing (52) and is mounted in axially movable manner in the
cylinder,
a driven flange (56) in which the hollow piston (57) is secured and
which is located in the upper housing part (51),
a blocking mechanism arranged in the upper housing part (51),
a spring housing (67) with the spring (68) located therein, which is
rotatably mounted on the upper housing part by means of a rotary
bearing,
a lower housing part (70) which can be fitted onto the spring housing (67) in the axial direction.
19. Atomiser as claimed in any one of claims 17 and 18, having a
blocking mechanism in the form of a helical thrust gear, with a
blocking member (62) arranged in annular configuration with
engaging locking surfaces and an actuating button (64),
20. Atomiser as claimed in any one of claims 17 to 20, having a
mechanical counter having a spindle (74) and a slider (76), which
is mounted on the spring housing (67) in the region of the outer
surface, and the axis of which runs parallel to the axis of the
spring housing (67).
21. Atomiser as claimed in any one of claims 17 to 20, having a nozzle
member (54) consisting of two glass and/or silicon plates firmly
joined together, at least one plate having one or more
microstructured channels which connect the nozzle inlet end to the
nozzle outlet end, and the nozzle outlet end has at least one
opening less than or equal to 10 µm in size.
22. Atomiser as claimed in claim 21, having a nozzle member (54)
having at least two nozzle openings at the outlet end, the
directions of spraying being inclined relative to one another and meeting in the vicinity of the nozzle openings.
23. Atomiser as claimed in any one of claims 17 to 22, having a non
return valve mounted in the pump housing (52) between the nozzle
opening and high pressure chamber of the cylinder.
24. Atomiser as claimed in any one of claims 17 to 23, having a hollow
piston (57) which exerts a pressure of 5 to 60 Mpa (about 50 to
600 bar) on the fluid at its end facing the nozzle (high pressure
end) at the moment of actuation of the spring (68).
25. Atomiser as claimed in claim 24, having a hollow piston (57) which
exerts a pressure of 10 to 60 Mpa (about 100 to 600 bar) on the
fluid at its end facing the nozzle (high pressure end) at the moment
of actuation of the spring (68).
26. Atomiser as claimed in any one of claims 17 to 25, having a
replaceable storage container (71) for the fluid (72) arranged in the
lower housing part.
27. Storage container for a fluid, containing a pharmaceutical
composition, for use in an atomiser as claimed in claim claims 17
to 26.
28. Atomiser as claimed in any one of claims 17 to 27 whenever used
for producing medicinal aerosols without propellant gas.
29. Storage container as claimed in claim 27, containing a
pharmaceutically acceptable solution of a medicament selected
from the group comprising; berotec, berodual, flunisolide, atrovent,
salbutanol, budesonide, combivent, tiotropium, oxivent and
suitable peptides.
30. Miniaturised device for producing high pressure substantially as
hereinbefore described with reference to the accompanying
drawings.
31. Atomiser for atomising a fluid substantially as hereinbefore
described with reference to the accompanying drawings.
32. Storage container for a fluid substantially as hereinbefore
described with reference to the accompanying drawings.

Documents:

2162-del-1996-abstract.pdf

2162-del-1996-claims.pdf

2162-del-1996-correspondence-others.pdf

2162-del-1996-correspondence-po.pdf

2162-del-1996-description (complete).pdf

2162-del-1996-drawings.pdf

2162-del-1996-form-1.pdf

2162-del-1996-form-13.pdf

2162-del-1996-form-19.pdf

2162-del-1996-form-2.pdf

2162-del-1996-form-29.pdf

2162-del-1996-form-3.pdf

2162-del-1996-form-6.pdf

2162-del-1996-gpa.pdf

2162-del-1996-pct-210.pdf

2162-del-1996-petition-137.pdf

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Patent Number

221998

Indian Patent Application Number

2162/DEL/1996

PG Journal Number

32/2008

Publication Date

08-Aug-2008

Grant Date

14-Jul-2008

Date of Filing

01-Oct-1996

Name of Patentee

BOEHRINGER INGELHEIM INTERNATIONAL GmbH

Applicant Address

D-55216 INGLHEIM AM RHEIN, GERMANY.

Inventors:

#	Inventor's Name	Inventor's Address
1	JOACHIM EICHER	GUSTAV-KORTHEN-ALLEE 24, D-44227 DORTMUND, GERMANY.
2	JOHANNES GESER	BOENSCHSTRASSE 11A, D-4427 DORTMUND, GERMANY.
3	PASQUALE CIRILLO	AM PASTORENWA IDCHEN 16, D-44229 DORTMUND, GERMANY.
4	JOACHIM JAEGER	FRANZ-BLAESI-STRASSE 3, D-76646 BRUCHSAL, GERMANY.

PCT International Classification Number

F04B 1/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	195 36 902.5-15	1995-10-04	Germany