Yarn clamping device

Abstract

The invention relates to a yarn clamping device for a spindle for releasably clamping a yarn in a clamping gap, comprising a first clamping unit having an inner sleeve which can be arranged coaxially with respect to the spindle and a yarn separator which can be fixed to the inner sleeve in the axial direction, the first clamping unit being fixable in an axially positionable manner on an upper part of the spindle, and a second clamping unit having a clamping member which is axially positionable relative to the first clamping unit between a clamping position for closing a clamping gap between the yarn separator and the clamping member and an open position for releasing the clamping gap. According to the invention, the yarn separator is designed for axially positionable fixation on the upper part of the spindle as well as for a non-rotatable connection with the upper part of the spindle, it being provided that the yarn separator and the inner sleeve are connectable in a non-rotatable manner with respect to each other.

Description

[Technical field]

[0001] The present invention relates to a yarn clamping device for a spindle of a spinning or twisting machine for releasably clamping a yarn in a clamping gap, - a first clamping unit having an inner sleeve which can be arranged coaxially relative to the spindle and a yarn separator which can be fixed to the inner sleeve in the axial direction, the first clamping unit being fixable while being axially positioned on an upper part of the spindle; and a second clamping unit having a clamping member that is axially positionable relative to the first clamping unit between a clamping position that closes a clamping gap between the yarn separator and the clamping member and an open position that releases the clamping gap.

[0002] Yarn clamping devices of the type mentioned at the outset are known in various embodiments from the prior art, for example from DE 10 2011 076 744 A1, by means of which so-called wound yarns can be clamped on spinning or twisting machines when changing full yarn reels.

[0003] For this purpose, the yarn clamping device usually has a first and a second clamping unit which are attached to the rotatable upper part of the spinning or twisting spindle. The first clamping unit has, for example, an inner sleeve which is attached to the rotatable upper part of the spinning or twisting spindle so as to be non-rotatable relative to it, and a yarn separator which bears on one end against the inner sleeve at its end face, and which is fixed at the other end to the upper part of the spinning or twisting spindle for axial positioning. In contrast, a second clamping member, for example an outer sleeve which is arranged coaxially with the inner sleeve, is supported so as to be axially movable relative to the rotatable upper part of the spinning or twisting spindle as well as with respect to the first clamping unit and is held, for example via a spring, in a clamping position which closes the clamping gap between the yarn separator and the second clamping member up to a certain number of revolutions of the spinning or twisting spindle.

[0004] The second clamping member is then configured to clamp the yarn in the clamping gap when in the clamping position without the centrifugal bias caused by the rotation of the upper part of the spinning or twisting spindle, whereas under the influence of centrifugal forces an axial displacement of the second clamping member takes place in the direction of the release position in which the yarn fixed in the clamping gap is released.

[0005] In the known yarn clamping device, the connection area of ​​the upper part of the spinning or twisting spindle for the rotationally non-rotatable connection with the inner sleeve of the first clamping unit is designed in a knurled manner. When assembled, the knurled area bites into the inner sleeve, so that a circumferentially acting positive connection is created between the inner sleeve and the upper part of the spinning or twisting spindle. However, the knurled design of the upper part of the spinning or twisting spindle places high demands on the manufacture of the spinning or twisting spindle. If, for example, the edge of the knurled area is not designed sharp enough, it will not bite into the plastic of the inner sleeve in a defined manner when the inner sleeve is assembled on the upper part of the spinning or twisting spindle. This results instead in a material-displacement process in which the inner sleeve is pressed radially outwards, which results in a regional increase in the outside diameter of the inner sleeve. This can result in undesirable friction between the inner sleeve and the clamping member which is axially displaceable relative to the inner sleeve, which can lead to blockage and subsequent failure of the thread clamping device.

[0006] Alternatively, it is known from German Patent Application No. 10 2011076744 A1 to design the inner surface of the inner sleeve with an annular surface with a toothing for engaging into a corresponding contour of the spindle surface. This solution also imposes high demands on the manufacture of both the inner sleeve and the spindle surface. If the toothing is designed incorrectly, material displacement can also occur on the side of the inner sleeve, which presses the inner sleeve radially outwards.

[0007] SUMMARY OF THE DISCLOSURE In light of the above, it is an object of the present invention to provide a yarn clamping device which enables a rotationally-locked connection between the spindle and the inner sleeve of a spinning or twisting machine in a simple and reliable manner.

[0008] The invention solves this problem by means of a thread clamping device having the features of claim 1. Preferred developments of the invention are set out in the dependent claims.

[0009] The thread clamping device according to the invention has a first and a second clamping unit. The first clamping unit comprises an inner sleeve which can be arranged coaxially with respect to the spindle and a thread separator which can be fixed to the inner sleeve in the axial direction, the first clamping unit being fixable in an axially positionable manner on an upper part of the spindle. The second clamping unit has a clamping member which can be axially adjusted relative to the first clamping unit between a clamping position in which the clamping gap between the thread separator and the clamping member is closed and an open position in which the clamping gap is released. The second clamping unit can have a conventional design known from the prior art. For example, the clamping member of the second clamping unit can be designed as a one- or multi-part outer sleeve which is supported by the inner sleeve so as to be movable relative to the inner sleeve. For this purpose, the inner sleeve and the outer sleeve or the clamping member can have corresponding bearing and sliding means on their respective inner or outer surfaces which are operatively connected to each other. As bearing means, projections and recesses which can be engaged with each other are mentioned purely by way of example. The corresponding configuration of the inner sleeve and the clamping member allows a guided relative movement of the clamping member with respect to the inner sleeve, whereby the sliding means can preferably be formed by a conventional centrifugal unit having a number of centrifugal members supported between the inner sleeve and the clamping member in such a way that, depending on the rotational speed of the spindle, the clamping member is movable relative to the inner sleeve for the corresponding opening and closing of the clamping gap.

[0010] The yarn clamping device according to the invention is characterized in that the yarn separator is designed for axially positioning and fixing on the upper part of the spindle and for a rotationally non-rotatable connection with the upper part of the spindle, the yarn separator and the inner sleeve being connectable to each other. To arrange the yarn clamping device on the upper part of the spindle of a spinning or twisting machine, the inner sleeve of the first clamping unit is fitted onto the upper part of the spindle. The axial position of the inner sleeve in the fitting direction is preferably determined by a corresponding design of the spindle, for example by a projection or a step against which the inner sleeve can rest at one end on the end face. According to the invention, the yarn separator serves to axially fix the inner sleeve against the fitting direction on the spindle and is axially defined on the spindle and operatively connected at the other end to the inner sleeve.

[0011] According to the invention, the thread separator is intended to serve, in addition to the axial positioning of the inner sleeve, for the purpose of connecting the spindle and the inner sleeve in a non-rotatable manner, so that the thread separator can be connected at least non-rotatably with the inner sleeve, preferably with the upper part of the spindle. Accordingly, in addition to axially positioning the inner sleeve at least at the upper part of the spindle against the fitting direction of the inner sleeve, the thread separator also serves to connect the inner sleeve in a non-rotatable manner with the spindle, and when the thread separator is in a position for axially positioning the inner sleeve at the upper part of the spindle, it further connects the first clamping unit in a non-rotatable manner with the upper part of the spindle. Through the non-rotatable connectability of the inner sleeve with the thread separator when the thread separator is in this position, a non-rotatable connection of the inner sleeve at the upper part of the spindle is realized, so that a separate design of the spindle with a connection area for a non-rotatable connection with the inner sleeve can be omitted.

[0012] The yarn clamping device thus enables a particularly simple and secure mounting of the inner sleeve on the upper part of the spindle in a non-rotatable manner, and deformations of the inner sleeve which would result in operational problems, for example in cooperation with a coupling element on the upper part of the spindle, can be effectively avoided. The yarn clamping device according to the invention enables a particularly simple and cost-effective connection of the spindle to the yarn clamping device.

[0013] The non-rotatable connection between the upper spindle part and the thread separator can in principle be implemented in any manner, for example through a form-fit connection, in which a rotation-lock between the upper spindle part and the thread separator is achieved through a specific shaping. In a preferred embodiment of the invention, it is provided that the thread separator can be press-fitted into the upper spindle part.

[0014] In this embodiment of the invention, the thread separator is connected to the upper part of the spindle non-rotatably by a press fit when the thread clamping device is in its mounted position on the spindle, the press fit being designed to ensure a reliable positioning of the inner sleeve in the axial direction of the spindle at least against the mounting direction of the inner sleeve, and also to ensure a locking of the inner sleeve relative to the spindle. The press fit between the spindle and the thread separator can be established particularly simply and cost-effectively.

[0015] For the rotationally-locked connection between the inner sleeve and the yarn separator, in a preferred embodiment of the invention it is provided that the yarn separator can be connected to the inner sleeve in a frictionally-locked, material-locked and / or form-locked manner. A frictionally-locked connection can be produced, for example, by a suitable configuration of the surfaces of the contactable faces of the yarn separator and the inner sleeve, the pressure force and the friction occurring between the faces ensuring a reliable lock. A materially-locked connection can be produced, for example, by means of gluing.

[0016] In order to establish a form-fitting connection, a preferred development of the invention provides that the thread separator has an engagement element which can be brought into engagement with the contact area of ​​the inner sleeve, in particular can be pressed into the contact area. In this embodiment of the invention, the thread separator is designed in such a way that, in the contact area with the inner sleeve, the engagement element of the thread separator is pressed into the inner sleeve at a defined position when or before the thread clamping device is assembled on the spindle, so that a form-fitting connection is established between the inner sleeve and the thread separator. This preferred embodiment of the invention allows a substantially clearance-free and non-rotating arrangement of the inner sleeve on the spindle in a particularly reliable and simple manner. Furthermore, this preferred embodiment of the thread separator produces an axially positioning fixation of the first clamping unit on the upper part of the spindle not only in the fitting direction of the inner sleeve, but also in the opposite direction. In this preferred embodiment, it is also possible to dispense with elements for fixing the inner sleeve in the fitting direction on the upper part of the spindle or on the spindle itself.

[0017] Particularly preferably, the engaging elements can be pressed into the contact areas of the inner sleeve, which is made of a material that can be deformed by the action of force, in order to clamp the inner sleeve on the upper part of the spindle. For example, selected or all of the engaging elements of the yarn separator can be designed with respect to their respective dimensions in such a way that, when the yarn clamping device is assembled on the spindle, the engaging elements are pressed into the contact areas of the inner sleeve, which is made of a material that contains plastics, for example, and a material displacement occurs in the direction of the center of the inner sleeve, which results in a reduction of the inner diameter of the inner sleeve at the corresponding material displacement point, and thus a clamping force is generated that clamps the inner sleeve on the upper part of the spindle. The yarn separator can generally be made of a material that contains metal, so that in particular the engaging elements can be pressed into the contact areas of the inner sleeve particularly reliably and easily in this preferred embodiment. It is particularly preferred that the yarn separator made of a material that contains metal is produced by a sintering method, as opposed to the usual lathing method. This allows the engaging elements, which are particularly made of a polygonal shape, to be formed on the yarn separator with great precision. The first clamping unit can thereby be fixed in a simple and reliable manner to the upper spindle part both in the circumferential direction and in the axial direction, without the need for any further fixing elements on the inner sleeve and / or on the upper spindle part, wherein the inner diameter of the inner sleeve is preferably selected depending on the outer diameter of the upper spindle part in such a way that it allows the inner sleeve to be fitted onto the upper spindle part and allows the clamping action by pressing in the engagement element.

[0018] In another preferred embodiment of the invention, it is provided that the contact area of ​​the inner sleeve has a coupling element which can be operatively connected to the engagement element. In this embodiment of the invention, coupling elements adapted to the shape of the engagement elements of the thread separator are arranged in the contact area of ​​the inner sleeve, which cooperate in a form-fitting manner in the circumferential direction with the corresponding engagement elements when the thread clamping device is mounted on the spindle, thereby ensuring a secure, anti-rotational connection. The engagement elements and the coupling elements can then be particularly preferably configured as a toothing which allows a particularly secure, anti-rotational axial positioning of the inner sleeve through the thread separator, both in the axial and circumferential directions.

[0019] In another preferred embodiment of the invention, a connecting element is arranged in the region between the contact area and the yarn separator, which is configured for a frictionally and / or positively non-rotatable connection of the contact area and the yarn separator. In this preferred embodiment of the invention, the connecting element serves as an adapter element which can be connected in an axially non-rotatable manner both to the yarn separator and to the contact area of ​​the inner sleeve. The use of a connecting element thus makes it possible to connect the yarn separator and the inner sleeve in a non-rotatable manner in the connecting region, regardless of their respective configuration. The connecting element then serves as an adapter which connects at least to the yarn separator and the inner sleeve in a frictionally and / or positively non-rotatable manner in the circumferential direction, so that a mutually adjusted adaptation of the yarn separator and the contact area can be dispensed with.

[0020] The connecting element may furthermore preferably be configured to fix the first clamping unit axially and non-rotatably at the upper spindle part by clamping or interference fit. In this case, the connecting element may preferably be arranged at the upper spindle part with a press fit and / or has an engagement element as described above for generating a clamping effect with the upper spindle part by material displacement at the side of the thread separator and / or at the side of the contact area when the thread clamping device is assembled. Alternatively, the operative connection between the thread separator and the connecting element and / or between the contact area of ​​the inner sleeve and the connecting element may be such that a material displacement as described above at the side of the connecting element for clamping the first clamping unit at the upper spindle part is generated by providing a corresponding engagement element at the thread separator and / or at the contact area. The component with the material displacement or the corresponding component area is made of a material that is deformable under the action of force, for example a plastic-containing material. The inside diameter is then configured as explained above as a function of the outside diameter of the upper spindle part, so that a force action or an interference fit or a press fit can be produced by displacing the material.

[0021] In one preferred embodiment of the invention, it is provided for the connecting element to be configured as a fixing ring or a toothed ring which can ensure a friction-locking and / or form-locking non-rotatable connection in a particularly secure manner, the fixing ring providing a sufficient friction moment and the toothed ring ensuring a secure form-locking connection.

[0022] Furthermore, the thread separator can preferably be produced from a metal-containing material by a sintering process, which is different from what is known, so that in particular polygonal shapes can be produced more accurately.

[0023] Next, an embodiment of the present invention will be described with reference to the drawings. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a schematic diagram showing an exploded view of a thread clamping device according to one embodiment. [Diagram 2] 13 is a schematic perspective view showing another embodiment of the inner sleeve of the thread clamping device; FIG. [Diagram 3] 2 is a schematic perspective view showing a yarn separator of the yarn clamping device of FIG. 1. [Figure 4] FIG. 13 is a schematic perspective view showing another embodiment of the yarn separator. [Diagram 5] FIG. 13 is a schematic perspective view showing another embodiment of the yarn separator.

[0025] The yarn clamping device 1 shown in FIG. 1 for clamping a yarn in the upper part of a spindle (not shown here), in particular in a spinning or twisting machine, also not shown here, comprises an inner sleeve 3a of a first clamping unit 2 which can be arranged non-rotatably relative to the upper part of the spindle, which in addition to the inner sleeve 3a further has a yarn separator 4a which can be pressed into the upper part of the spindle, which yarn separator axially fixes the yarn clamping device 1 in the direction opposite to the direction of fitting onto the upper part of the spindle.

[0026] For the fixed connection between the upper spindle part and the inner sleeve 3a, the thread separator 4a, which can be pressed non-rotatably into the upper spindle part, has coaxially extending engaging elements 9 in the form of teeth 15 in the contact area with the inner sleeve 3a (see FIG. 3).

[0027] In the assembled state of the thread clamping device 1 on the upper spindle part, the teeth 15 are pressed into the contact area 8a of the inner sleeve 3a at the end side and cause a displacement of material of the contact area 8a in the direction of the inner sleeve center such that the inner sleeve is clamped axially and non-rotatingly on the upper spindle part, thus ensuring a non-rotating arrangement of the inner sleeve 3a on the upper spindle part. Alternatively or additionally, the thread separator 4a according to the further embodiment can be arranged non-rotatingly and axially fixed on the upper spindle part through a press fit.

[0028] Coaxially arranged relative to the inner sleeve 3a is a clamping member 6 which is axially slidable relative to the inner sleeve 3a, forming an outer sleeve which can be fitted over the inner sleeve 3a and which can slide relative to the inner sleeve 3a and the yarn separator 4a along a longitudinal axis 11 in a known manner. The faces of the yarn separator 4a and of the clamping member 6 which face towards each other form a clamping gap 7 of the yarn clamping device 1, in which the yarn can be clamped to the spindle. The axially slidable clamping member 6 is in this embodiment axially prestressed by a compression coil spring 12 and is arranged in a clamping position in which the clamping member 6 comes into contact with the yarn separator 4a when the spindle is at rest. For the automated sliding of the clamping member 6 in the direction towards the open position for releasing the yarn, the yarn clamping device 1 comprises in a known manner a centrifugal unit (not shown here), which comprises a number of centrifugal members which separate the axially slidable clamping member 6 from the yarn separator 4a as soon as the spindle rotates at a certain minimum RPM, thereby opening the clamping gap 7 and releasing the yarn located in the clamping gap 7.

[0029] Figure 2 shows, in a schematic and simplified manner, another embodiment of an inner sleeve 3b having a coaxially circumferential gearing 14 consisting of a number of connecting elements 10 for a rotationally non-rotatable connection in the contact area 8b with the thread separator 4a shown in Figure 3. The configuration of the gearing 14 on the inner sleeve 3b is adapted to the configuration of the gearing 14 of the thread separator 4a shown in Figure 3, so that a rotationally non-reliable connection between the thread separator 4a and the inner sleeve 3b is ensured in the assembled position of the thread clamping device 1 on the upper spindle part.

[0030] FIG. 4 shows a further embodiment of the thread separator 4b in which the connecting element 9 is formed by a spherical crown 16 which is pressed into the contact area 8a of the inner sleeve 3a when the first clamping unit 2 is assembled, thus ensuring a non-rotating connection via the thread separator 4b which is arranged non-rotatingly on the upper part of the spindle.

[0031] FIG. 5 shows a further embodiment of a yarn separator 4c in which the engagement elements 9 for the rotationally locked connection with the inner sleeve 3a are formed by a number of webs 17 arranged one behind the other in the circumferential direction, which form polygonally shaped contact surfaces which together with the contact areas 8a of the inner sleeve 3a establish a connection which acts in a form-fitting manner in the circumferential direction. [Explanation of symbols]

[0032] 1. Yarn clamping device 2 First clamp unit 3a, 3b Inner sleeve 4a, 4b, 4c Thread separator 5 Second Clamp Unit 6 Clamping member 7 Clamping Gap 8a, 8b contact area 9 Engagement member 10 Connecting members 11 Long axis 12 Compression coil spring 13 Sealing material 14 Meshing part 15 teeth 16 Ball crown 17 Web

Claims

1. A yarn clamping device (1) for a spindle of a spinning or twisting machine for releasably clamping a yarn in a clamping gap (7), comprising: - a first clamping unit (2) having an inner sleeve (3a, 3b) which can be arranged coaxially with respect to the spindle and a thread separator (4a, 4b, 4c) which can be fixed to the inner sleeve (3a, 3b) in the axial direction, said first clamping unit (2) being fixable while being axially positioned on an upper part of the spindle; and a second clamping unit (5) having a clamping member (6) which is axially positionable with respect to the first clamping unit (2) between a clamping position for closing the clamping gap (7) between the thread separator (4a, 4b, 4c) and the clamping member (6) and an opening position for releasing the clamping gap (7), the yarn separator (4a, 4b, 4c) is configured for axially positioning and fixing in the upper part of the spindle and for a non-rotatable connection with said upper part of the spindle, A yarn clamping device, characterized in that the yarn separator (4a, 4b, 4c) and the inner sleeve (3a, 3b) can be connected to each other in a non-rotatable manner.

2. 2. The thread clamping device (1) according to claim 1, characterized in that the thread separator (4a, 4b, 4c) can be press-fitted into the upper part of the spindle.

3. 3. The yarn clamping device (1) according to claim 1 or 2, characterized in that the yarn separator (4a, 4b, 4c) can be connected to the inner sleeve (3a, 3b) in a frictional and / or positively locking manner so as to be non-rotatable relative to the inner sleeve (3a, 3b).

4. The yarn clamping device (1) according to claim 1 or 2, characterized in that the yarn separators (4a, 4b, 4c) are made of a metal-containing material by a sintering process.

5. 3. The thread clamping device (1) according to claim 1 or 2, characterized in that the thread separator (4a, 4b, 4c) has an engagement member (9) which can be brought into engagement with or pressed into the contact area (8a, 8b) of the inner sleeve (3a, 3b).

6. 6. The thread clamping device (1) according to claim 5, characterized in that the engagement member (9) can be pressed into the contact area (8a) made of a deformable material in order to clamp the inner sleeve (3a) at the upper part of the spindle.

7. 6. The yarn clamping device (1) according to claim 5, characterized in that the contact areas (8a, 8b) have connecting members (10) which can be operatively connected with the engagement members (9).

8. 8. The yarn clamping device (1) according to claim 7, characterized in that the engagement member (9) and the connecting member (10) are configured as a toothed portion (14).

9. 6. The yarn clamping device (1) according to claim 5, further comprising a connecting member arranged in the region between the contact area (8a, 8b) and the yarn separator (4a, 4b, 4c), which is connected to the contact area (8a, 8b) and the yarn separator (4a, 4b, 4c) in a frictional and / or positively fixed manner so as to be non-rotatable relative to the contact area (8a, 8b) and the yarn separator (4a, 4b, 4c).

10. 10. The thread clamping device (1) according to claim 9, characterized in that the coupling element is configured as a fastening ring or a toothed ring.

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