Title of Invention

A SAFETY DEVICE FOR A PRESSURE COOKING APPLICATION WITH BAYONET CLOSURE

Abstract

A safety device for a pressure cooking application with bayonet closure, said device comprising: - a pan (1) having pan ramps (2); - a lid (3) having lid ramps (4); - a rotary abutment means (8) for preventing the lid (3) rotating relative to the pan (1), placed so that in the closed position the lid ramps (4) engage the pan ramps (2), the lid (3) and the pan (1) then being prevented from rotating in the direction of rotation that corresponds to closing the appliance; - locking means (10) for locking the lid (3) relative to the pan (1), the locking means being mounted to move on the appliance under drive from control means (11) suitable for being actuated by the user between at least one unlocking position enabling the appliance to be opened and at least one locking position in which relative rotation between the pan (1) and the lid (3) is prevented; and - a pressure indicator (30, 30A) mounted to move freely on the lid (3) * between a high, leakproof position and a low, leakage position, depending on the pressure that exists within the appliance, characterized in that the pressure indicator (30, 30A), the control means (11), and the locking means (10) form part of a unitary assembly (12) that is mounted on the lid (3) and that is independent of the handles (5) of the cooking appliance.

Full Text

FORM 2 THE PATENTS ACT, 1970 [39 OF 1970] COMPLETE SPECIFICATION [See Section 10; Rule 13] "A SAFETY DEVICE FOR A PRESSURE COOKING APPLICATION WITH BAYONET CLOSURE" SEB S.A., of Les 4M, Chemin du Petit-Bois, Boite Postale 172, F-69132 Ecully Cedex, France, The following specification particularly describes the nature of the invention and the manner in which it is to be performed:- TECHNICAL FIELD The present invention relates to a safety device for a pressure cooking application with bayonet closure and more particularly to the technical field of opening safety device for pressure cooking appliances having bayonet closures, implementing rotary abutment means for preventing rotation of the lid relative to the pan in a direction corresponding to closing the appliance, and means for locking the lid relative to the pan under drive from control means 'suitable for being actuated by the user, and suitable for taking up at least one locking position in which relative rotation between the lid and the pan is prevented. The present invention relates to an opening safety device for a pressure cooking appliance with bayonet closure and comprising: • a pan having pan ramps; • a lid having lid ramps; • rotary abutment means for preventing the lid rotating relative to the pan, placed so that in the closed position the lid ramps engage the pan ramps, the lid and the pan then being prevented from rotating in the direction of rotation that corresponds to closing the appliance; • locking means for locking the lid relative to the pan, the locking means being mounted to move on the appliance under drive from control means suitable for being actuated by the user between at least one unlocking position enabling the appliance to be opened and at least one locking position in which relative rotation between the pan and the lid is prevented; and • a pressure indicator mounted to move freely on the lid between a high, leakproof position and a low, leakage_ position, depending on the pressure that exists within the appliance. -2- The present invention also relates to a "bayonet" type pressure cooker fitted with an opening safety device of the invention. PRIOR ART As a general rule, the locking/unlocking devices of "bayonet" type pressure cookers implement locking principles that make use of alignment between a handle of the pan and a handle of the lid to trigger displacement of a latch, said displacement generally being along a radial direction relative to the axis of symmetry of the pan of the pressure cooker. Such a principle is disclosed, e.g. in patent FR-A-2 484 817 in the name of the Applicant. Patent FR-A-2 484 817 describes a pressure cooker whose handle includes a member for locking the lid relative to the pan, which member extends substantially radially relative to the wall of the pan and is mounted to be movable in a radial direction. The locking member is provided with an orifice that makes it possible, in the closed position, to pass an operating valve freely therethrough when the lid is properly closed. Incomplete closure will lead to the valve being out of alignment with the opening provided in the sliding locking member, thereby preventing any rise of pressure inside the pressure cooker, as a safety measure. Such systems are in widespread use on "bayonet" type pressure cookers, with that known locking/unlocking principle being suitable for implementation in numerous varieties and configurations, e.g. making the locking member act either directly or indirectly when the pressure cooker is put under pressure. Furthermore, there exist numerous configurations of openings depending on the level of safety provided by the design, in association with other safety devices, e.g. making use of one or more operating valves and/or deformation of a sealing gasket. -3- Such systems provide the user of a pressure cooker with a level of safety that is universally recognized, but give rise to various drawbacks during design and industrial manufacture. Thus, it turns out that the design of pressure cookers using locking on the above principle requires compliance with a chain of multiple design dimensions, and that is difficult to achieve. This chain of dimensions comprises a large stack of components such as the pan, the fixing pin for the handles, the locking member, the handle of the lid, the lid, the compression of the gasket, etc. Industrially, particularly during manufacture, this gives rise to major dimensional constraints on the manufacturer, and that naturally constitutes a significant industrial drawback. In addition, on that type of pressure cooker, there is only one single position for relative locking between the lid and the pan. Locking/unlocking devices for pressure cookers are also known that implement principles of locking and safety on opening that imply a certain amount of simplification. Thus, patent FR-A-1 052 130 describes a principle of locking and safety on opening implementing means for locking the lid relative to the pan, which means extends substantially parallel to the wall of the pan and is vertically movable. The locking means is mounted on the lid and is associated with control means, in association with a rated operating valve. The locking means is designed to penetrate into a cavity provided in the handle of the appliance to lock the pressure cooker while the rated operating valve is simultaneously put into action in its seat by its compression spring. Apart from the relatively rudimentary level of safety that it provides, such a system suffers from the drawback of still requiring compliance with a considerable chain of design dimensions, and of providing an insufficient level of safety. It is possible to open --4-- the appliance while a certain amount of excess pressure still exits in the pressure cooker, since unlocking is performed simultaneously when the operating valve is freed. The level of safety is therefore not optimal. SUMMARY OF THE INVENTION Consequently, the objects of the invention seek to remedy the various drawbacks enumerated above, and to propose a novel opening safety device for a pressure-cooking appliance having bayonet closure, that has improved safety and improved handling. Another object of the invention is to propose a novel safety device that allows the appliance to be cleaned easily and that allows the appliance to be cleaned in a dishwasher. Another object of the invention is to propose a novel safety device that is particularly simple to implement and make. Another object of the invention is to propose a novel safety device that is simpler to manipulate, and that provides an improved level of safety. A further object of the invention seeks to propose a novel safety device that is particularly robust and insensitive. The objects of the invention are achieved by a safety device for a pressure cooking appliance with bayonet closure and comprising: ■ a pan having pan ramps; • a lid having lid ramps; • rotary abutment means for preventing the lid rotating relative to the pan, placed so that in the closed position the lid ramps engage the pan ramps, the lid and the pan then being prevented from rotating in the direction of rotation that corresponds to closing the appliance; • locking means for locking the lid relative to the pan, the locking means being mounted to move on the -5- appliance under drive from control means suitable for being actuated by the user between at least one unlocking position enabling the appliance to be opened and at least one locking position in which relative rotation between the pan and the lid is prevented; and ■ a pressure indicator mounted to move freely on the lid between a high, leakproof position and a low, leakage position, depending on the pressure that exists within the appliance, the device being characterized in that the pressure indicator, the control means, and the locking means form part of a unitary assembly that is mounted on the lid and that is independent of the handles of the cooking appliance. BRIEF DESCRIPTION OF THE DRAWINGS The objects of the invention will be understood in greater detail on reading the following description made with reference to the accompanying drawings, given purely by way of non-limiting illustration, and in which: • Figure 1 is an overall plan view of a safety device of the invention fitted to a pressure cooker; • Figure 2 is a fragmentary cross-section view showing a detail of the safety device of the invention; • Figure 3 is a fragmentary plan view of a pressure cooker showing the safety device of the invention in its position corresponding to the open position of the pressure cooker; • Figure 4 is a view similar to Figure 3 showing the safety device of the invention in a position corresponding to the pressure cooker being closed and locked; • Figure 5 is a fragmentary cross-section view on line V-V of Figure 6 showing a detail of the safety device of the invention, in its opening position; • Figure 6 is a plan view in partial section with the positions of the various members making up the safety -6- device of the invention being in the same opening position as shown in Figure 5; • Figure 7 is a fragmentary cross-section view showing a detail of the safety device of the invention ii its locking position without pressure; • Figure 8 is a fragmentary plan view showing the positions of the various members making up the safety device of the invention in a locking position without pressure, identical to that of Figure 7; • Figure 9 is a fragmentary cross-section view showing the locking position of the safety device of the invention; and • Figures 10 and 11 are two fragmentary plan views showing the respective positions of the various members of the safety device of the invention, respectively in a first rated position of the operating valve, and in a second rated position of the operating valve. BEST MODE OF CARRYING OUT THE INVENTION Figures 1 to 11 show a safety device of the invention fitted to a pressure-cooking appliance with bayonet closure, constituting a pressure cooker. In conventional manner, the pressure cooker comprises a pan 1 that is generally cylindrical, being defined by a pan wall 1A having a series of pan ramps 2 in its top portion for co-operating with a lid 3 that is likewise provided at its periphery with lid ramps 4 to constitute a pressure cooker of the bayonet closure type. The pan ramps 2 and the lid ramps 4 are defined by conventional profiles each including two lateral edges 2A, 4A and a peripheral edge 2B, 4B. The pan 1 and the lid 3 are made in conventional manner from metal, such as stainless steel or aluminum, and they are made by stamping, for example. For handling purposes, the pressure cooker is fitted with handle members, e.g. a pair of handles 5 secured to the pan 1 and fixed in diametrically opposite positions -7- on the wall 1A. In the pressure cooker example shown in Figures 1 to 11, the lid 3 is provided on its outer top face, substantially in the middle thereof, with a handle 6 enabling the lid 3 to be held and to be rotated. > In conventional manner, the safety and locking/unlocking device of the invention includes rotary abutment means for preventing the lid 3 from rotating relative to the pan 1 and disposed so that in the closed position the lid ramps 4 engage the pan ramps 2, the lid 3 and the pan 1 then being prevented from rotating in the direction of rotation that corresponds to closing the appliance. The rotary abutment means can be implemented in the form of a series of complementary shapes, e.g. by means of a notch or indentation 8 (Figure 1) formed in the peripheral portion of the lid 3 for coming into abutment against a pan ramp 2 by being rotated from a starting position. The safety and locking/unlocking device of the invention also includes locking means 10 for locking the lid 3 relative to the pan 1, and mounted to move relative to the appliance, specifically the pressure cooker, under drive from control means 11 (e.g. Figures 1 and 7) suitable for being actuated by the user between at least one unlocking position enabling the appliance to be opened, and at least one locking position in which rotation of the lid 3 relative to the pan 1 is prevented. The locking means 10 acts by preventing the lid 3 from rotating relative to the pan 1 in the direction for opening the appliance. In association with the abutment means 8, it ensures that the pan and the lid are locked together by preventing any relative rotation between these two pieces. According to the invention, the locking means 10 is mounted to move in translation along the wall of the pan wall 1A in the inter-ramp zone (Figures 2, 5, and 9) so that the in locking position it bears against the lateral edge 2A of one of the pan ramps 2. In this disposition, -8- the locking means 10 extends substantially parallel to the wall of the pan 1, on the outside and at a distance from said wall in the zone between the pan ramps 2 and the lid ramps 4 as defined by the annular zone between two diameters, namely the diameter defined by the top edge of the pan wall 1A of the pan and the diameter defined by the drop edge 3A of the lid 3 (Figure 2). In this manner, and as can be seen in Figures 3 and 4, for example, the locking means 10 can come into the locking position shown in Figure 4 when the lid 3 is in its abutment position defined by the abutment means 8. In this position, the pan ramps 2 and the lid ramps 3 are superposed and in engagement, such that in the vicinity thereof the inter-ramp zone is empty and it is possible for the locking means 10 to pass therethrough. After the locking means 10 has moved in translation, for example and preferably vertically, it is thus close to and in a position flush with the lateral edge 2A of the pan ramp 2. The lid 3 and the pan 1 are then prevented from rotating relative to each other in both directions of rotation. In a particularly advantageous version of the invention, the locking means 10 and the control means 11 are mounted on the lid 3 and are integrated, for example, in or on a block 12 which is preferably integrated in a removable unitary assembly (Figure 1) that is mounted on the lid 3 and that is independent of the handles 5. The unitary assembly or the block 12 is mounted, e.g. by screwing, on the top face of the lid 3, in any zone outside of the handles 5 of the pan. The active safety unit formed by the unitary assembly 12, forming a control panel, is thus secured to the lid 3 and can be secured to or removed from the lid 3 as desired. Its position on the appliance also disengages it completely from the position and shape of the handles. Overall, the total size of the appliance is reduced, it is easier to handle, and it is generally safer to use. -9- In another particularly advantageous variant of the invention, the locking means 10 is formed by a pin, e.g. a cylindrical metal pin, mounted on the lid 3 substantially parallel to the wall of the pan 1, and it is mechanically and functionally connected to the control means 11. For example, within the block 12, the pin 13 can be supported by a support plate 14. According to the invention, the control means 11 includes a selector knob 15 mounted to rotate on the block 12 between at least two positions, and preferably between three or four positions, the knob acting directly or indirectly on the locking means 10. In a preferred variant of the invention, the selector knob 15 acts indirectly on the control means 11, specifically on the pin 13, via a lever (e.g. Figures 6, 8, 10, and 11) hinged between said knob and said control means, and providing a mechanical interface between the selector knob 15 and the locking means 10. The movement in translation of the pin 13 in a substantially vertical direction is obtained by rotating the lever 16. The lever is hinged, substantially halfway along, by a pivot 17 and has one end that flares to form a circular arc 18 designed to engage the control means 10, and in particular the top portion of the pin 13. The preferred mounting is such that the end 18 engages in a slot 19 (Figure 2) of substantially helical shape that is formed in and at the periphery of the pin 13 so that by rotating about its pivot 17 the pivoted lever 16 moves the pin 13 in translation from its locking position to its unlocking position, and vice versa. It is also possible to envisage reversing this mechanical mount with the sloping control ramp being formed on the end 18 for moving the pin 13, or indeed to make a slot in the end 18 and a ramp on the pin 13. The mounting must thus be designed so that the end 18 engages and co-operates with the pin 13 via helically-shaped co-operation means disposed -10- respectively on the pin 13 and on the end 18 to move the pin 13 longitudinally. As shown for example in Figure 7 and in Figures 6, 8, 10, and 11, the selector knob 15 is mounted to rotate on the block 12 via a substantially vertical central pin 20. A collar 21 is angularly secured to the pin 20 and is of sufficient size to extend over and cover at least part of the second end 22 of the pivoted lever 16, over an angular sector of rotation. The second end 22 extends in part beneath the collar 21, and towards its end edge it includes a vertical finger 23 mounted to engage in a guide slot formed in the collar 21, which slot has a circular portion 25 and a radial portion 26. By means of this configuration, the vertical finger 23 is guided in the guide slot, and depending on how the selector knob 15 is rotated, the lever 16 can be caused to move in rotation about its pivot axis 17. According to a characteristic of the invention, the safety device also has a pressure indicator 30 mounted to move freely on the lid 3, preferably in or on the block 12 so that it moves in a seat receiving it between a high position and a low position, depending on the high or low pressure that exists within the appliance. The high position is leakproof, and the low position provides leakage. The pressure indicator 30 is in the form of a cylindrical peg 30A mounted to move in vertical translation in a seat 31, itself secured to the plate 14 included in the block 12, for example. The bottom orifice 32 of the seat 31 opens out through the lid 3 into the enclosure constituted by the pan of the pressure cooker. The cylindrical peg 30A and the seat 31 are shaped so that when the cylindrical peg 30A- is in its high position it presses in leakproof manner against the seat 31, whereas when it is in its low position it is possible for pressure to leak out. The low position thus corresponds to a pressure-leakage position. -11- As shown in particular in Figures 6, 8, 10, and 11, the pressure indicator 30, the locking means 10, and the control means 11 are advantageously organized and mounted relative to one another in such a manner that: • when the control means 11 and the locking means 10 occupy their unlocking positions, the control means 11 prevents the pressure indicator 30 from moving away from its low position; and • when the control means 11 and the locking means 10 occupy their locking positions corresponding to the opening position of the appliance, the control means 11 leaves the pressure indicator 30 free to move, but is capable of being held in the locking position if the indicator 30 is in its high position. In the invention, the control means 11 comprises, as described above, a selector knob 15 mechanically and functionally associated with the locking means 10 via the pivoted lever 16 acting via its end 18 on the locking means 10 to displace it. In addition, the pivoted lever 16 also acts via its end 18 on the pressure indicator 30 to lock it in the low position. To this end, the pressure indicator 30 is mounted relative to the pivoted lever 16 so that its end 18 covers the pressure indicator 30, specifically the cylindrical peg 30A, when the selector knob 15 is in the unlocking position (Figure 6) to prevent it from rising. In order to reach this unlocking position, corresponding to the selector knob 15 being in a position referenced 0 in Figures 1 and 6, the pivoted lever 16 has been pivoted in the direction marked Fl in Figure 6, causing the pin 13 to move vertically upwards, and it has come to cover the cylindrical peg 30A while in its low position. In this position, the pressure indicator 30 is in its pressure-leakage position and it is prevented from moving by the presence of the end 18. It is thus possible to open or close the pressure cooker. However, the end 18 of the pivoted lever 16 is situated in the vicinity of nit; piessure muicator 30 so that in the locking position, e.g. corresponding to Figure 8 (position referenced V in Figure 1), the pressure indicator 30 is free to move, said lever when in this position being suitable for being locked against the pressure indicator 30. Advantageously, the end 18, when in this position, is laterally flush with the outer periphery of the pressure indicator 30. Advantageously, as shown in Figures 8, 10, and 11, the convex circularly-arcuate end 18 has a curved side edge 18A, e.g. in the form of a concave circular arc, for matching the shape of the periphery of the cylindrical peg 30A. In all of the positions shown in Figures 8, 10, and 11, corresponding respectively to the positions marked V, I, and II in Figure 1, the locking means 10 is in its low locking position and the pressure indicator 30 can move upwards freely. If a minimum amount of pressure exists within the enclosure of the pressure cooker, it becomes impossible for the user to place the selector knob 15 in the opening position since the pressure indicator 30 in its high position limits rotation of the pivoted lever 16. In a particularly advantageous variant of the invention, the control means 11 is mechanically and functionally associated via the selector knob 15 with a rated operating valve 40 (Figure 7) for the purpose of setting the rating. The rated operating valve 40 is mounted in or on the block 12, and in conventional manner it is mounted to move freely in resilient manner by resilient means such as a helical spring (not shown in the figures) within the seat. The rated operating valve 40 is also subjected to the internal pressure that exists inside the enclosure of the pressure cooker via an orifice 41 situated towards its bottom portion and opening out into the pan 1. The top portion 42 of the rated operating valve 40 is in contact with the selector knob 15 so as to be driven thereby. In the variant embodiment shown in Figure 7, the selector knob 15 is in contact with the rated operating valve 40 by means of the collar 21 which acts via a cam profile 44 on the top portion 42. Advantageously, the cam profile 44 is designed so as to act on the rated operating valve 40 against its resilient means in at least two set positions. Thus, the selector knob 15 acts on the rated operating valve 40 by occupying two positions corresponding respectively: ■ to the locking position V (e.g. Figure 1) in order to release it from any resilient compression against the resilient compression means (the operating valve 40 is thus subjected only to the action of its own weight); and • to a first compression position representative of a first rated value, e.g. corresponding to the appliance operating at a relative pressure limited to about 550 millibars. Advantageously, the selector knob 15 acts on the rated operating valve 40 in a second compression position (Figure 11) also representative of a second rating value for the resilient means, e.g. corresponding to the appliance operating under a limiting pressure of about 900 millibars relative. In the locking position of the locking/unlocking system of the invention, the cam profile 44 is flush with the top portion 42, for example, in such a manner as to exert no compression on the resilient means, thereby releasing the rated operating valve 40. The cam profile 44 is then regularly inclined obliquely so as to compress the resilient means by increasing amounts corresponding to the two rated positions as defined above and to the two rotary positions of the selector knob 15. Naturally, it is possible to envisage a device that has more than three operating positions for the operating valve without thereby going beyond the ambit of the invention. Finally, and as shown in Figure 7 for example, the safety device of the invention can also include auxiliary safety devices, such as a safety valve 50. In accordance with the invention, the locking means 10, the control means 11, and the rated operating valve 40 are integrated in a unitary assembly including the block 12 which is removably mounted on the lid 3 by any appropriate means, e.g. by screws. In a preferred variant of the invention, as shown in Figures 2, 5, and 9, for example, the locking means 10, and specifically the pin 13, passes through a sealing gasket 51 mounted in conventional manner between the lid 3 and the pan 1. Advantageously, the pin 13 passes through the sealing gasket 51 to act as means for indexing said gasket and for preventing it from rotating in the lid 3. In conventional manner, the sealing gasket 51 is made of an elastomer material and has two lips 52 and 53, for example. The sealing gasket 51 has a hole 54 formed through its main body in such a manner that in the unlocking position, the sealing gasket 51 can be engaged on the pin 13 via the hole 54. This prevents the sealing gasket 51 from rotating in the lid 3. The locking/unlocking mechanism of the invention operates as follows. To close and open the appliance, the selector knob 15 must be moved by the user into its opening position marked 0. In this position (e.g. Figures 5 and 6), the pin 13 is in its high position and the pressure indicator 30 is necessarily in its low position since the pivoted latch 16 limits vertical displacement thereof since the curved portion 18 overlies said indicator. The pressure inside the appliance cannot be raised since the pressure indicator 30 is in its low position in which it is possible for pressure to leak out between the pan 1 and the lid 3. It is thus possible for the user to open and close the appliance, without taking any particular precautions, by rotating the lid 30, e.g. in the direction F2 shown in Figure 1, so as to reach the position shown in dashed lines in Figure 1. To close the appliance, the user must firstly position the lid 3 on the pan 1 in the position shown in dashed lines in Figure 1. The user then rotates the lid 3 in the direction opposite to arrow F2 so that it takes up the position shown in continuous lines in Figure 1. To close the appliance, the selector knob 15 (which during all the preceding operations has been in the position marked 0) is turned by the user into the locking position marked V, as shown in Figure 8. While it is being rotated, the selector knob 15 rotates the pivoted lever 16 which firstly uncovers the pressure indicator 30, and secondly moves the pin 13 downwards. The movement of the end 18 in the guide slot of the pin 13 causes the pin 13 to move downwards substantially vertically and locks the lid 3 for rotation relative to the pan 1 since the pin 13 comes flush against the lateral edge 2A of the pan ramp 4 (Figure 4). If the user wishes to open the appliance, then the selector knob 15 must be turned to position 0. Furthermore, the pressure indicator 30 is free to move upwards. Nevertheless, since the selector knob 15 is in its locking position V, the rated operating valve 40 is free to move without resilient constraint, which prevents the pressure inside the pressure cooker from rising. In order to allow pressure to rise, the user must position the selector knob in the first rated position (Figure 10). While moving into said position, the pivoted latch 16 remains stationary since the finger 23 can move freely in the circular portion 23 of the guide slot in the collar 21. Since the rated operation valve 40 is now elastically compressed, the pressure inside the appliance can rise. Depending on the type of cooking desired, the user can also position the selector knob 15 in the second rating position, as shown in Figure 11, for example. In this second position, the pin 13 is still -16- naturally in its locking position since the pivoted lever 16 has not moved, the finger 23 merely reaching its end position in the guide slot. Furthermore, with the pressure indicator 30 in its high position because of the pressure, it is impossible for the user to place the selector knob 15 in the opening position. While in its high position, the pressure indicator 30 prevents the pivoted lever 16 from rotating, thereby causing it to act as a latch. If the user seeks to open the appliance, it is therefore necessary firstly to place the selector knob 15 in the locking position V where the rated operating valve 40 becomes free to allow steam to escape, thereby causing the pressure contained inside the appliance to drop. Once the pressure has dropped below a value of about 0.5 kPa, for example, the pressure indicator 30 returns to its low position, thereby enabling the user to turn the selector knob 15 into the opening position 0. The pivoted lever 16 can now be rotated so as to reach the position O (Figure 6), thereby enabling the pin 13 to move upwards in translation under drive from the pivoted lever 16. The pin 13 thus reaches its unlocking position, thereby enabling the pressure cooker to be opened in complete safety, all pressure having been evacuated previously. The invention consequently makes it possible to lock the pan and the lid together directly and to obtain complete safety for the appliance since the pressure cannot raise inside the appliance if it is poorly closed, and it can be opened only by necessarily passing initially via the locking position V in which any remaining excess pressure within the pressure cooker is evacuated. In addition, the appliance can be opened only if the internal pressure within the appliance tends to zero. The locking mechanism is also independent of the handles of the pan, thereby simplifying construction of the appliance. WE CLAIM:- 1. A safety device for a pressure cooking application with bayonet closure, said device comprising: - a pan (1) having pan ramps (2); - a lid (3) having lid ramps (4); - a rotary abutment means (8) for preventing the lid (3) rotating relative to the pan (1), placed so that in the closed position the lid ramps (4) engage the pan ramps (2), the lid (3) and the pan (1) then being prevented from rotating in the direction of rotation that corresponds to closing the appliance; - locking means (10) for locking the lid (3) relative to the pan (1), the locking means being mounted to move on the appliance under drive from control means (11) suitable for being actuated by the user between at least one unlocking position enabling the appliance to be opened and at least one locking position in which relative rotation between the pan (1) and the lid (3) is prevented; and - a pressure indicator (30, 30A) mounted to move freely on the lid (3) * between a high, leakproof position and a low, leakage position, depending on the pressure that exists within the appliance, characterized in that the pressure indicator (30, 30A), the control means (11), and the locking means (10) form part of a unitary assembly (12) that is mounted on the lid (3) and that is independent of the handles (5) of the cooking appliance. 2. A device as claimed in claim 1, wherein the unitary assembly (12) is removable mounted. - 19- 3. A device as claimed in claim 1 or 2, wherein the pressure indicator (30, 30A) is mounted so that: - when the control means (11) and the locking means (10) occupy their unlocking positions, the control means (11) prevents the pressure indicator (30, 30A) from moving away from its low position; and - when the control means (11) and the locking means (10) occupy their locking positions, the control means (11) leaves the pressure indicator (30, 30A) free to move, but is capable of being held in the locking position if the indicator (30, 30A) is in its high position. 4. A device as claimed in anyone of claims 1 to 3, wherein the control means (11) includes a selector knob (15) mechanically associated with the locking means (10) via a pivoted lever (16) acting via an end (18) on the locking means (10) to displace it, and on the pressure indicator (30, 30A) to lock it. 5. A device as claimed in claim 4, wherein the locking means (10) is formed by a pin (13) substantially parallel to the pan wall (1A), and in that the end (18) engages in and co-operates with the pin (13) via co-operation means of substantially helical shape to move the pin (13) longitudinally. 6. A device as claimed in claim 4 or 5, wherein the end (18) of the lever (16) covers the pressure indicator (30, 30A), in the unlocking position, to prevent it from rising, and is situated in the vicinity of the indicator (30, 30A), in the locking position, to enable it to move, said lever (16) being suitable for being locked against the pressure indicator (30, 30A). -20- 7. A device as claimed in anyone of claims 4 to 6, wherein the control means (11) is mechanically associated via the selector knob (15) with a rated operating valve (40) for the purpose of setting the rating. 8. A device as claimed in claim 7, wherein the selector knob (15) acts via a cam profile (44) on the rated operating valve (40) in at least two positions. 9. A device as claimed in-claim 8, wherein the selector knob (15) acts on the rated operating valve (40) in two positions corresponding respectively to the locking position in order to release it from any resilient compression, and to a first compression position representative of a first rated value. 10. A device as claimed in claim 9, wherein the selector knob (15) acts on the rated operating valve (40) in a second compression position representative of a second rated value. 11. A pressure cooker fitted with a device as claimed in anyone of claims 1 to 10. Dated this 22nd day of March, 2001. -21 -

Documents:

abstract1.jpg

in-pct-2001-00323-mum-cancelled pages(10-06-2005).pdf

in-pct-2001-00323-mum-claims(granted)-(10-06-2005).doc

in-pct-2001-00323-mum-claims(granted)-(10-06-2005).pdf

in-pct-2001-00323-mum-correspondence(24-06-2005).pdf

in-pct-2001-00323-mum-correspondence(ipo)-(13-03-2007).pdf

in-pct-2001-00323-mum-drawing(10-06-2005).pdf

in-pct-2001-00323-mum-form 1(22-03-2001).pdf

in-pct-2001-00323-mum-form 1a(10-06-2005).pdf

in-pct-2001-00323-mum-form 2(granted)-(10-06-2005).doc

in-pct-2001-00323-mum-form 2(granted)-(10-06-2005).pdf

in-pct-2001-00323-mum-form 3(10-06-2005).pdf

in-pct-2001-00323-mum-form 3(22-03-2001).pdf

in-pct-2001-00323-mum-form 5(22-03-2001).pdf

in-pct-2001-00323-mum-form-pct-ipea-409(22-03-2001).pdf

in-pct-2001-00323-mum-form-pct-isa-210(22-03-2001).pdf

in-pct-2001-00323-mum-petition under rule 137(10-06-2005).pdf

in-pct-2001-00323-mum-power of authority(06-04-2001).pdf

in-pct-2001-00323-mum-power of authority(10-06-2005).pdf