|Title of Invention||
THREAD TAKE- OFF ROLLER FOR A TEXTILE MACHINE PRODUCING CROSS - WOUND BOBBINS
|Abstract||The invention relates to a thread take-off roller for a textile machine which produces crosswound bobbins, for the frictional transport of a thread which is produced in a spinning device. According to the invention, there is provision for the external circumference (7) of the thread take-off roller (10) to be formed by a thin-walled metal ring (11) which is profiled by hydroforming.|
|Full Text||FORM 2
THE PATENT ACT 1970 (39 of 1970)
The Patents Rules, 2003 COMPLETE SPECIFICATION
(See Section 10, and rule 13)
TITLE OF INVENTION
THREAD TAKE-OFF ROLLER FOR A TEXTILE MACHINE PRODUCING CROSS-WOUND BOBBINS
a) Name :
b) Nationality :
c) Address :
OERLIKON TEXTILE GMBH & CO. KG
D-410 6 9 MOENCHENGLADBACH,
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed : -
ENGLISH TRANSLATION VARIFICATION
CERTIFICATE u/r. 20(3)(b)
I, Mr. HIRAL CHANDRAKANT JOSHI, an authorized agent for the applicant, OERLIKON TEXTILE GMBH & CO. KG do hereby verify that the content of English translated complete specification filed in pursuance of PCT International application No. PCT/ EP2006/ 006793 thereof is correct and complete.
The invention relates to a thread take-off roller for a textile machine producing cross-wound bobbins according to the preamble of claim 1.
Textile machines producing cross-wound bobbins, in particular open-end spinning devices have, in the region of their workstations, thread take-off mechanisms, which draw the thread produced in a spinning device out of the spinning device and convey it in the direction of a winding mechanism, where the thread is wound to form a cross-wound bobbin.
The known thread take-off devices either, as described in DE 44 32 240 Al, for example, have a drive shaft along the length of the machine or the thread take-off mechanisms are driven by a single motor. A thread take-off mechanism of this type is the subject of DE 101 39 075 Al, for example.
The thread take-off mechanisms according to DE 44 32 240 Al in each case consist of a relatively thick-walled, hardened and chrome-plated take-off tube, which is non-rotatably fixed in the region of the workstations on the drive shaft along the length of the machine, as well as a pivotably mounted, rubber-hooped pressure roller, which is entrained by the take-off tube by frictional engagement. These known thread take-off mechanisms have the disadvantage, however, that because of the continuous drive shaft, they are only suitable for drawing off the thread during the regular spinning operation but not for returning the thread end into the spinning device in conjunction with the piecing process.
Thread take-off mechanisms with a thread take-off roller which can be driven by a single motor are described, for example, in DE 101 39 075 Al. These known thread take-off devices in each case have a relatively large single motor-driven thread takeoff roller and a significantly smaller, pivotably mounted pressure roller. The thread take-off roller which can be driven in a reversible manner by a stepping motor,
consists, in this case, of a rotationally symmetrical diecast or injection-moulded body, the outer periphery of which is machined so as to be thread-smooth and is preferably chrome-plated. Disadvantageous in these known thread take-off mechanisms are, above all, the production costs of the thread take-off rollers. In other words, the necessary, relatively laborious machining of the surface that comes into contact with the thread makes such thread take-off rollers relatively expensive.
Proceeding from the aforementioned prior art, the invention is based on the object of developing a thread take-off roller with a thread-smooth surface, which can be produced economically.
This object is achieved according to the invention by a thread take-off roller as described in claim 1.
Advantageous configurations of the invention are the subject of the sub-claims.
According to the invention, the outer periphery of the thread take-off roller is formed by a thin-walled metal ring manufactured from an abrasion-resistant material, which is fixed on a rotationally symmetrical base body of the thread takeoff roller. The metal ring in this case has a profiling which ensures a reliable take-off of a thread manufactured, for example, in an open-end spinning device during the entire spinning process.
The profiling of the thin-walled metal ring, as described in claim 6, preferably took place by internal high pressure forming, which in particular has the advantage that the metal ring produced in this manner is immediately thread-smooth without any aftertreatment.
Internal high pressure forming is a known manufacturing method per se in conjunction with hollow bodies and allows relatively economical, reproducible production even of complicated components. In this method described, for example,
in DE 41 03 082 and also known as hydrostatic forming, a hollow body made of a cold-formable metal is placed in the die cavity of a die and then pressed by hydraulic fluid, which is injected at high pressure, against the die wall. The die wall in this case, in accordance with the desired profiling of the tube, has hollows into which the material of the tube is pressed during the forming process with the formation of uniform, smooth radii.
As the thin-walled metal ring immediately has its final, thread-smooth profiling, following the forming process, further machining steps can be dispensed with. Internal high pressure forming is therefore a method which allows hollow bodies to be produced precisely and economically.
Steel, preferably an alloy made of a so-called special steel has proven to be successful as the material for the metal ring, as shown in claim 2.
Metal rings produced from special steel are not only very corrosion-resistant but also relatively abrasion-resistant, so the wear of the profiling can be kept within reasonable limits.
As shown in claim 3, the wall thickness of the thin-walled metal ring is between 0.1 mm and 0.4 mm, preferably 0.2 mm. Hollow bodies with a relatively small wall thickness of this type can be machined relatively free of problems, on the one hand, by means of internal high pressure forming, but, on the other hand, when they have been profiled and when they have been drawn onto their support body, for example the base body of the thread take-off roller, they have the required rigidity.
As described in claim 4, the profiling of the metal ring preferably consists of a plurality of webs arranged spaced apart from one another in the direction of rotation. When it is being taken off the spinning device, the thread is entrained relatively gently, in this case, via the webs. Because of the profiling of the metal ring, the slip between the thread take-off roller and thread is kept within narrow limits
both during the uniform operation and during the acceleration phases of the winding device.
According to claim 5, it is also provided in an alternative embodiment that the internal high pressure-formed metal ring is coated. The service life of the metal ring can be extended by a coating of this type.
The invention will be described in more detail below with the aid of an embodiment shown in the drawings, in which:
Fig. 1 shows a perspective view of a workstation of a textile machine producing cross-wound bobbins, with a thread take-off device driven by a single motor, and a thread take-off roller according to the invention,
Fig. 2 shows the thread take-off roller according to the invention with a connected drive in a side view, partially in section,
Fig. 3 shows the thread take-off roller according to the invention according to the section III-III of Fig. 2.
Fig. 1 shows a perspective view of a workstation of an open-end rotor spinning machine. The workstation is designated as a whole by the reference numeral 1. Workstations 1 of this type, as known and therefore only shown schematically, substantially have an open-end spinning device 2 for producing a thread 9 and a winding device 3, which allows the thread 9 to be wound into a cross-wound bobbin 8.
The thread 9 produced in the open-end spinning device 2 is drawn off by a thread take-off device 27, which has a drivable thread take-off roller 10 and a pressure roller 14 which can be pivoted to the thread take-off roller 10, from the open-end spinning device 2.
The thread 9 leaves the open-end spinning device, in this case, through a so-called thread take-off tube 21. Also arranged in the region of the open-end spinning device 2 is a pivotably mounted auxiliary piecing member 16, which, after a thread break, takes over the thread 9 returned from the cross-wound bobbin 8 by a suction nozzle 4 and prepares the thread end for repiecing.
Furthermore, a stop motion 26, a waxing mechanism 62 as well as thread storage mechanisms 60 or 61 are arranged downstream of the thread take-off mechanism 27 in the thread running direction. The thread storage mechanism 61 is configured here as a negative pressure-loadable storage nozzle, while the storage mechanism 60 is configured as a mechanical thread store. In other words, arranged between two stationary thread guide members is an adjustable thread guide member which, driven by a stepping motor 58, is movably arranged relative to the thread running path.
The winding mechanism 3, as conventional, consists of a creel 22 for the rotatable holding of a cross-wound bobbin 8, a drive drum 23, which is preferably driven by a reversible single drive 56, as well as a thread traversing mechanism 24 which is driven, for example, by a stepping motor 57. A thread centring mechanism in the form of a pivotably mounted centring plate 17, which if necessary can be folded by a drive 55 in a defined manner into the regular thread running path, may also be arranged upstream of the thread traversing mechanism 24.
Furthermore, the workstation 1, as already indicated above, has a suction nozzle 4, which can be adjusted by means of a stepping motor 6 in a defined manner between a thread receiving position located in the region of the winding device 3 and a thread transfer position located in the region of the spinning device 2.
The individual stepping motors are, as indicated, connected to a winding head computer 25 via control lines.
The thread take-off mechanism 27, which is shown in more detail in a side view or in a front view in Fig. 2 and 3, partially in section, substantially consists of a thread take-off roller 10 which can be driven by a stepping motor 13 and of a pressure roller 14 which can be pivoted to the thread take-off roller 10. The thread take-off mechanism 27 ensures both the drawing off of the spinning thread 9 from the open-end spinning device 2 during the regular spinning operation and also the return of a prepared thread 9 into the open-end spinning device 2 during repiecing.
The thread take-off roller 10 in detail consists of a rotationally symmetrical base body 15, manufactured by the diecasting method, for example, on the outer periphery 7 of which a thin-walled metal ring 11, which is profiled by internal high pressure forming and preferably consists of steel or a special steel alloy, is fixed. The thin-walled profiled metal ring 11 is in contact with the thread 9 during the winding operation and, in connection with the adjacent pressure roller 14 ensures that thread 9 is continuously drawn from the open end spinning device 2.
The profiling of the thin-walled metal ring 11 in this case preferably consists, as indicated in Figs. 2 and 3, of webs 12 which are distributed over the entire periphery of the metal ring 11 and are arranged spaced apart from one another in the direction R of rotation of the drive roller.
As already explained above, the thin-walled metal ring 11 receives its profiling in an advantageous manner by internal high pressure forming. In this method which is known per se and described, for example, in DE 41 03 082 Al, which is also called hydrostatic forming, a hollow body consisting of cold-formable metal is placed in a die, into which, in accordance with the desired profiling, recesses are worked. By means of an incompressible medium, preferably a hydraulic fluid, which is injected at a very high pressure into the interior of the hollow body, the thin-walled tube is pressed into the recesses present on the inner wall of the die. In other words, the formation of the inner wall of the die provides the final form of the component to be produced with regard to its final dimensions or its exact physical configuration.
As in each case relatively smooth radii are produced in the region of the bending edges, the finished components already have the final finish, in other words, further aftertreatments, such as, for example, deburring are not necessary.
Therefore, even relatively complicated series components can be produced relatively economically and with a very precise fit by internal high pressure forming.
1. Thread take-off roller for a textile machine producing cross-wound bobbins for the frictional transport of a thread produced in a spinning device, characterised in that the outer periphery (7), which is formed as a thin-walled metal ring (11), of the thread take-off roller (10) is profiled.
2. Thread take-off roller according to claim 1, characterised in that the thin-walled, profiled metal ring (11) consists of steel, preferably a stainless special steel alloy.
3. Thread take-off roller according to claim 1, characterised in that the thin-walled, profiled metal ring (11) has a wall thickness of between 0.1 mm and 0.4 mm, preferably 0.2 mm.
4. Thread take-off roller according to any one of the preceding claims, characterised in that the thin-walled, profiled metal ring (11) has a profiling which is stepped in the direction (R) of rotation of the thread take-off roller (10), for example in the form of webs (12).
5. Thread take-off roller according to claim 1, characterised in that the thin-walled, profiled metal ring (11) is coated.
6. Method for producing a thread take-off roller according to claim 1, characterised in that the profiling of the external periphery (7), which is formed as a thin-walled metal ring (11), of the thread take-off roller (10) takes place by means of internal high pressure forming.
The invention relates to a thread take-off roller for a textile machine which produces crosswound bobbins, for the frictional transport of a thread which is produced in a spinning device. According to the invention, there is provision for the external circumference (7) of the thread take-off roller (10) to be formed by a thin-walled metal ring (11) which is profiled by hydroforming.
The Controller of Patents
The Patent office
|Indian Patent Application Number||569/MUMNP/2008|
|PG Journal Number||09/2013|
|Date of Filing||26-Mar-2008|
|Name of Patentee||OERLIKON TEXTILE GMBH & CO. KG|
|Applicant Address||LANDGRAFENSTRASSE-45, D-41069 MOENCHENGLADBACH,|
|PCT International Classification Number||D01H4/40,B65H51/10|
|PCT International Application Number||PCT/EP2006/006793|
|PCT International Filing date||2006-07-12|