The present invention relates to a rotor cup in which a fiber material can be spun, and a coupling device for a detachable connection of the rotor cup to a rotor shaft provided. The coupling device comprises at least one connecting means for the transfer of torque from the rotor shaft provided to the rotor cup and for the axial securing of the rotor cup on the rotor shaft. At least one centering means is provided for centering the rotor cup on the rotor shaft.
Furthermore, the invention relates to an open-end spinning rotor with a rotor cup, in which a fiber material can be spun, and with a rotor shaft, by means of which the spinning rotor can be supported in a bearing, in particular a magnetic bearing, whereas the rotor shaft and the rotor cup are detachably connected to one another by means of a coupling device. Whereas the coupling device comprises connecting means for the transfer of torque between the rotor cup and the rotor shaft and for the axial securing of the rotor cup on the rotor shaft and centering means for centering the rotor cup and rotor shaft.
From the state of the art, connecting a rotor cup and a rotor shaft to an open-end spinning rotor is sufficiently known. Such spinning rotors run with rotor speeds of 150,000 rpm and higher, which is why the connection between the rotor cup and the rotor shaft must be extremely reliable. In addition to the high degree of support of the rotor cup in the rotor shaft, the highest precision is required to maintain the yarn quality, which is why the spinning rotors or the rotor cups have to be changed after a certain running time. However, particularly in the case of non-contact bearings, replacing the entire spinning rotor with the rotor shaft is costly, such that it is frequently the case that the rotor cups are detachably connected to the associated rotor shaft.
A proposal for the implementation of a detachable connection is described in EP 1 156 142 B1. In this, the rotor cup features a ferromagnetic attachment from which one section serves the purpose of centering, and a second section is provided with an outer polygon for the transfer of torque. A permanent magnet serves the purpose of axial securing. The production of the rotor cup with the two-piece attachment with the outer polygon and the rotor shaft with the corresponding inner polygon is comparatively complex.
A further development of the coupling device described above is shown in EP 2 730 686 B1. In this, the centering between the rotor shaft and the rotor cup is to be improved by providing a clearance fit between a cylindrical bore of the rotor shaft and the section of the attachment of the rotor cup serving the purpose of centering. Furthermore, an elastic arrangement is to be provided between the bore and the cylindrical section.
A task of the present invention is to propose a rotor cup along with an open-end spinning rotor, which can be produced easily and enables a good centering of the rotor cup on the rotor shaft. Additional objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
The tasks are solved with the characteristics of the invention described and claimed herein.
A rotor cup in which a fiber material can be spun is proposed. The rotor cup features a coupling device for a detachable connection to a rotor shaft provided for it. The coupling device comprises at least one connecting means for the transfer of torque from the rotor shaft to the rotor cup. The transfer of torque between the rotor cup and the rotor shaft preferably takes place by means of a positive-locking connection. The rotor cup is arranged in a manner protected against rotation with respect to the rotor shaft, such that a rotational relative movement is prevented between such two components. Furthermore, the coupling device comprises at least one connecting means for the axial securing of the rotor cup on the rotor shaft, which can be formed as a single piece with or separately from the connecting means for the transfer of torque. The rotor cup is fixed by the at least one connecting means with maximum hold on the rotor shaft. In addition, the coupling device comprises at least one centering means for centering the rotor cup on the rotor shaft.
According to a first design of the rotor cup, the centering means comprises a cone-shaped extension or a cone-shaped receiver on the rotor cup. The extension is preferably formed on the rotor cup and the receiver is preferably formed on the rotor shaft. The extension corresponds to the receiver in the form of a conical bore, such that the rotor cup is centered on the rotor shaft if such two components are connected to one another. The extension of the rotor cup can be detachably inserted into the receiver of the rotor shaft. The rotor cup and the rotor shaft cooperate with one another through the extension inserted into the receiver. The extension and the receiver are preferably cone-shaped, with a cone angle of 10° to 30°. The cone angle, in particular its angle of inclination, is selected in such a manner that it is not self-locking, such that the connection is easily detachable at any time. The cone-shaped receiver or the cone-shaped extension effect a particularly good centering of the rotor cup on the rotor shaft, and can nevertheless be produced in a comparatively simple manner, for example, by turning.
Particularly in the case of a rotor cup with a cone-shaped extension or a cone-shaped receiver, it is advantageous if the extension features an attachment or the receiver features a recess. The attachment or the recess is preferably formed to be rotationally symmetrical, in particular cylindrical. With this, the attachment can serve the purpose of both the improved guidance of the rotor cup on the rotor shaft. However, the attachment can also enable the integration of additional functions without impairing the centering or the conical seat. For example, the attachment can be formed in one or multiple edges, in order to be able to cooperate with a corresponding recess of the rotor shaft, which is likewise formed in one or multiple edges. As a result, additional anti-rotation protection of the rotor cup is provided with respect to the rotor shaft for the transfer of torque, while the cone-shaped extension or the cone-shaped receiver serves the purpose of centering.
If the extension is designed in a cone shape, it is also advantageous if the cone-shaped extension features a ring-shaped circumferential elevation, in particular a bulge. Owing to production tolerances, it is frequently the case that the cone-shaped extension and the corresponding cone-shaped receiver feature a slightly different angle of inclination. Since, with the connection between the rotor cup and the rotor shaft, only small axial clamping forces can be applied, such production tolerances cannot be compensated for by an elastic deformation of the extension and the associated receiver, such that throughout the length of the extension it can come into contact only at a ring-shaped line or a very short cylindrical area. Here, the length of the extension is understood as the spread of the extension in the direction of its axis of rotation, and thus in the direction of the axis of the spinning rotor or of the rotor cup and of the rotor shaft. This can be counteracted by the bulge, since the bulge is more easily elastically deformable at lower forces and thus creates a defined contact area.
Preferably, the elevation is arranged in an area of the extension turned towards the rotor cup or a rotor base of the rotor cup; that is, in relation to a length of the extension, the elevation is arranged closer to the beginning of the extension that adjoins the actual rotor cup or the rotor base than at the end of the extension. The contact area, which is defined by the elevation, is thereby advantageously located close to the actual rotor cup or the rotor base. Thus, the unsupported part of the rotor cup projecting out of the receiver is shorter, which results in better support of the rotor cup in the rotor shaft.
With a rotor cup with a cone-shaped extension or a cone-shaped receiver, it is further advantageous if the centering means and the connecting means are formed, at least partially, in one piece with one another. The one-piece design of the centering means or the connecting means enables a very precise and, at the same time, cost-effective production of the rotor cup. The means necessary for the connection, such as, for example, grooves or toothings, are formed directly on the centering means, thus on the cone-shaped extension or the cone-shaped receiver. Therefore, different sections need not be provided on the extension or the receiver; rather, both functions can also be realized in a single section.
According to an alternative design of the rotor cup, the centering means comprises at least one centering element, which is formed separately from the connecting means. The centering element comprises a cylinder pin fixed in the rotor cup or a centering bore arranged in the rotor cup for receiving a cylinder pin of the rotor shaft. The connecting means comprises a preferably cylindrical extension on the rotor cup. The extension corresponds to a receiver of the rotor shaft. With this, the centering of the rotor cup and its torque-transferring and/or axially securing connection to the rotor shaft takes place by means of various components, namely the separate cylinder pin along with the extension formed on the rotor cup. The arrangements or means, such as, for example, grooves, toothings or the like, necessary for the axially securing and/or torque-transferring connection are arranged separately from the centering means on a separate component. The centering is effected directly by means of the cylinder pin. This also ensures a very precise connection of the rotor cup with the rotor shaft, and creates cost-effective production, since the cylinder pins can be sourced as standard parts. Since the connecting means is completely separate from the centering means, this cannot adversely affect the centering of the rotor shaft and the rotor cup. At the same time, the establishment of the connecting means at the rotor cup and on the rotor shaft is facilitated, since this can be carried out at any desired location and in any manner, independently of the centering means.
Advantageously, the extension is formed in one piece on the rotor cup. Thereby, the production of the rotor cup is achievable in a few steps. Furthermore, the connecting means thereby withstands very high forces. This design is therefore advantageous both for a cone-shaped extension and for an extension that is formed cylindrically or in another shape.
It is further advantageous if the cylinder pin is fixed (in particular, pressed) into the rotor cup. In order to compensate for the air pressure when introducing the cylinder pin of the rotor cup into the cylinder bore of the rotor shaft, it is additionally advantageous if the cylinder pin features a pressure compensation bore. The pressure compensation bore preferably extends through the entire length of the cylinder pin. If the cylinder pin is pressed into the rotor cup, the rotor cup preferably features a bore adjacent to the pressure compensation bore of the cylinder pin. When the rotor cup and the rotor shaft are joined together, the pressure is compensated for by the air exiting through the pressure compensation bore.
It constitutes an advantage if the receiver of the rotor cup features a first circumferential groove of the rotor cup or if the extension of the rotor cup features a second circumferential groove. A securing element for the axial securing of the rotor cup at the rotor shaft can then be inserted into it. Correspondingly, it is also advantageous if a securing element for the axial securing of the rotor cup on the rotor shaft is inserted, as a connecting means, into the first circumferential groove of the receiver or into the second circumferential groove of the extension. Alternatively, the circumferential groove can cooperate with a securing element arranged on the rotor shaft.
The securing element is preferably an O-ring or a snap ring. The securing element is preferably made of an elastomeric material. Vulcanizates of natural rubber and synthetic rubber are also conceivable as materials for the securing element. Alternatively, however, an axial securing of the rotor cup by means of a magnet can also be realized, as in the state of the art. If the rotor cup and the rotor shaft are connected to one another, the O-ring is pressed into the respective circumferential grooves of the rotor cup and the rotor shaft, by which at least an axial securing is possible.
It is advantageous if the securing element is a snap ring made of spring steel. The snap ring is formed from a spring steel wire, which is bent into a ring. The ends of the spring steel wire are usually at least slightly spaced from one another, such that the circumference of the snap ring is not completely closed. The snap ring is preferably arranged on the rotor cup, such that the rotor cup, when driven, is pulled into the receiver. The receiver comprises an inclined groove flank, into which the snap ring is pulled when the rotor cup is driven. For the use of the snap ring, either the rotor cup or the rotor shaft features a circumferential groove for receiving the snap ring. The respective other component preferably also features a circumferential groove with an inclined groove flank. By means of the snap ring, it is possible to realize high axial forces. Furthermore, the axial support is extremely strong. The snap ring transfers the axial forces acting on the inclined groove flank.
Alternatively, it is advantageous if the securing element is an O-ring made of an elastomeric material. The O-ring is preferably used if there is a clearance between the rotor cup and the rotor shaft that is compensated for by the O-ring. The two circumferential grooves are axially slightly offset relative to each other if the rotor cup and the rotor shaft are connected to one another. As a result, the O-ring arranged on the rotor cup pulls the rotor cup in an axial manner into the receiver of the rotor shaft.
The first circumferential groove of the receiver advantageously features an inclined groove flank. The securing element located in the groove, which is in particular formed as a snap ring or O-ring, widens during operation, due to the high rotational speed of the spinning rotor, and presses against the inclined groove flank. In particular with a coupling device with a conical extension, the rotor shaft and the rotor cup are thereby pulled together even further, such that, thereby, the axial securing between the rotor cup and the rotor shaft provided for it is further improved.
Advantageously, the securing element serves the purpose of, at the same time, transferring the torque from the rotor shaft to the rotor cup. By means of the securing element, a force-fitting connection for anti-rotation protection is formed between the rotor shaft and the rotor cup. Thereby, the production effort can be reduced, since a component takes over several functions.
As an alternative or in addition to the above-described force-fitting connection for anti-rotation protection, it is advantageous if the extension or the receiver features at least one form closure element and forms a positive-locking connection for the transfer of torque from the rotor shaft to the rotor cup. The form closure element is, for example, a claw-type coupling, but can also feature any other shape suitable for the transfer of torque. Thereby, the transfer of torque between the rotor shaft and the rotor cup is highly reliable.
It constitutes an advantage if the at least one form closure element of the extension is arranged on the cylindrical attachment, or if the at least one form closure element of the receiver is arranged in the recess.
In addition, an open-end spinning rotor with a rotor cup, in which a fiber material can be spun, and a rotor shaft, are proposed. By means of the rotor shaft, the spinning rotor can be supported in a bearing, in particular in a magnetic bearing. The rotor shaft and the rotor cup are detachably connected to one another by means of a coupling device. The coupling device comprises connecting means for the transfer of torque between the rotor cup and the rotor shaft and for the axial securing of the rotor cup on the rotor shaft. Furthermore, the coupling device comprises centering means for centering the rotor cup and the rotor shaft.
According to a first embodiment, the centering means comprises a cone-shaped extension on one of the two components (rotor cup or rotor shaft), along with a cone-shaped receiver in the respective other component, into which the extension can be detachably inserted. The extension is preferably formed in one piece with the component that includes the extension. As already described for the rotor cup, the cone angle is preferably 10° to 30° and is selected in such a manner that it is not self-locking. Thereby, a particularly good centering between the rotor cup and the rotor shaft can be achieved and, at the same time, a cost-effective production of the spinning rotor is enabled. With this, the extension is preferably formed on the rotor cup and the receiver is formed on the rotor shaft, but a reverse arrangement is also conceivable.
It is advantageous if the extension features an attachment and the receiver features a recess, which are preferably formed to be rotationally symmetrical, in particular cylindrical. As already described, the attachment can serve the purpose of both the improved guidance of the rotor cup on the rotor shaft and the realization of additional functions of the coupling device, for example the transfer of torque, independently of the tapered connection.
It is further advantageous if the centering means and the connecting means are formed, at least partially, in one piece with one another. The means necessary for the connection, such as, for example, grooves, toothings or the like, are preferably formed directly on the centering means or set of centering means, in particular on the cone-shaped attachment and/or the cone-shaped receiver.
Alternatively, the centering means comprises at least one centering element formed separately from the connecting means. The centering element comprises a cylinder pin, which is fixed (in particular, pressed) into one of the two components (rotor cup or rotor shaft). The cylinder pin can be detachably inserted into a centering bore of the respective other component, which forms a centering means on the respective other component. Furthermore, the connecting means comprises a preferably cylindrical extension on the rotor cup and a preferably cylindrical receiver on the rotor shaft, into which the extension of the rotor cup can be inserted. Thus, the centering means and the connecting means are provided by various components, whereas the centering is effected through the cooperation of the cylinder pin and the centering bore, while the connection (that is, the axial securing and/or the transfer of torque) between the rotor cup and the rotor shaft is effected through the continuation of the rotor cup along with the receiver of the rotor shaft. Possible arrangements for additional connecting means such as grooves, toothings or the like are not undertaken on the centering means, but on the extension, such that the functions of centering and connecting are provided on separate components. The production of the open-end spinning rotor is simplified by the cylinder pin. Problems of fitting are also reduced.
It is also advantageous if the extension and/or the receiver are connected in one piece to the rotor shaft or the rotor cup. In principle, however, it would also be possible to provide the extension and/or the receiver as separate components and then connect them to the rotor shaft or to the rotor cup.
Advantageously, the cylinder pin is fixed (in particular, pressed) into the rotor shaft. The cylinder pin is thereby arranged in a manner protected against damage.
It is advantageous if the centering means and the connecting means are formed, at least partially, in one piece with one another. This enables a highly cost-effective production of the spinning rotor, since the two functions of centering and connecting can be realized on a single component and also in a single section of the same component.
Advantageously, the open-end spinning rotor features a rotor cup in accordance with the preceding description.
Further advantages of the invention are described in the following embodiments. The following is shown:
Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.
In the present case, the first part 3 of the coupling device 4 of the rotor cup 1 contains a cone-shaped extension 8 and a securing element 13, in the present case an O-ring as a connecting means 6 on the rotor cup 1. The second part 5 of the coupling device 4 of the rotor shaft 2 comprises a cone-shaped receiver 10 along with a first circumferential groove 11 as a connecting means 6 on the rotor shaft 2. In the present case, the O-ring is arranged in a second circumferential groove 12 of the extension 8, but could also be arranged in the first circumferential groove 11 of the receiver 10. The two circumferential grooves 11, 12 are offset relative to one another in such a manner that the rotor cup 1 is pulled in an axial manner into the conical receiver 10 of the rotor shaft 2 if the rotor cup 1 and the rotor shaft 2 are connected to one another. Furthermore, it would also be conceivable for only one of the two parts (the receiver 10 or the extension 8) to feature a circumferential groove 11, 12. The extension 8 along with the corresponding receiver 10 of the rotor shaft 2 are, at the same time, formed as a centering means 7, in such a manner that the rotor cup 1 can be centered in the rotor shaft 2.
However, in the present case, as already described, the extension 8 also serves, at least partly, as a connecting means 6. The same applies to the receiver 10, which is described in the following with reference to
Each of the extension 8 and the receiver 10 corresponding to the extension 8 features an angle of inclination of 10° to 30°. In the present case, the extension 8 is formed in one piece with the rotor cup 1, but could also be a separate component connected thereto.
With the following description of the additional figures, the same reference signs are used for characteristics that have already been described in connection with
The inclined groove flank 18 is now arranged in such a manner that the securing element 13, in this case the snap ring 27, widens and presses against the groove flank 18 if the rotor cup 1 is connected to the rotor shaft 2 and circulates at high rotational speed during operation. As a result, the rotor cup 1 is pulled in an axial manner onto the rotor shaft 2, or in particular into the recess 17a, such that a particularly good connection is achieved between the rotor shaft 2 and the rotor cup 1. In doing so, such a circumferential groove 11 with an inclined groove flank 18 can be used both with a securing element 13, which serves only for axial securing, and, also with a securing element 13, which can serve the purpose of axial securing and the transfer of torque.
By way of derogation from that shown in
An additional embodiment (not shown) is described below on the basis of
However, by way of derogation from the illustration of
The snap ring 27 and the groove flank 18, on the other hand, in turn constitute connecting means 6 for the axial securing of the rotor cup 1 on the rotor shaft 2. In addition, at least in part, a force-fitting transfer of torque between the rotor cup 1 and the rotor shank 2 can also be effected through the snap ring 27 and the groove flank 18.
The centering of the rotor cup 1 and the rotor shaft 2 is effected through the cooperation of the cone-shaped extension 8 and the cone-shaped receiver 10, on which, as described above, at least a part of the connecting means 6 is arranged, or at the same time at least a part of the connecting means 6 is presented. Consequently, the centering means 7 and the connecting means 6 are partially formed in one piece. Such commonality features the previously described embodiments 1 to 4.
A centering bore 22 is arranged in the rotor shaft 2 as the centering means 7; it corresponds to the cylinder pin 21 of the rotor cup 1 and also forms a centering means 7. The cylinder pin 21 features a pressure compensation bore 23. The pressure compensation bore 23 extends from the cylinder pin 21 into the rotor cup 1, such that the air pressure is compensated upon the connection of the rotor cup 1 to the rotor shaft 2.
The coupling device 4 further comprises a form closure element 24 for the transfer of torque from the rotor shaft 2 to the rotor cup 1. In the present case, a part of a claw coupling 25 is provided as a form closure element 24 on the rotor cup 1 and also on the rotor shaft 2 corresponding to it. Thus, just like the edged recesses 17b or attachments 17a described above, the form closure elements 24 also form connecting means 6 for the transfer of torque. In the present case, a magnet 26 is provided in the rotor shaft 2 as a connecting means 6 for axial securing. The claw coupling 25 is shown in detail in
Thus, the centering element 20, in particular the cylinder pin 21, is formed completely separately from the connecting means 6, in particular from the form closure element 24 arranged on the extension 8 and the receiver 10 for the transfer of torque and the magnet 26 for axial securing.
The centering of the rotor cup 1 and of the rotor shaft 2 continues to be effected through the cylinder pin 21 and the corresponding centering bore 22 as the centering means 7. The snap ring 27 cooperates jointly with the inclined groove flank 18 in accordance with
This invention is not limited to the illustrated and described embodiments. Variations within the scope of the claims, just as the combination of characteristics, are possible, even if they are illustrated and described in different embodiments.
LIST OF REFERENCE SIGNS
1 Rotor cup
2 Rotor shaft
3 First part of a coupling device
4 Coupling device
5 Second part of a coupling device
6 Connecting means
7 Centering means
8 Extension
9 O-ring
10 Receiver
11 First circumferential groove
12 Second circumferential groove
13 Securing element
14 Open-end spinning rotor
15 Bearing
16
a Cylindrical attachment
16
b Edged attachment
17
a Cylindrical recess
17
b Edged recess
18 Groove flank
19 Torque-transferring surface
20 Centering element
21 Cylinder pin
22 Centering bore
23 Pressure compensation bore
24 Form closure element
25 Claw coupling
26 Magnet
27 Snap ring
28 Elevation
Number | Date | Country | Kind |
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10 2016 122 595.9 | Nov 2016 | DE | national |