THREAD BRAKE

Description

[0001] The present invention relates to a thread brake comprising a first disc, a second disc, a disc carrier and a tensioning device which applies a force to the first disc in the direction of the second disc, wherein the first disc and the second disc are mounted on an eyelet carrier which has a thread guide eyelet through which a thread path runs.

[0002] DE 35 24 151 A1 discloses a thread brake for textile machines comprising a first disc, a second disc, a disc carrier, and a tensioning device that applies a force to the first disc in the direction of the second disc. The two discs are arranged on a bolt that carries a thread holder, which in turn has a through-opening through which a thread path runs.

[0003] A similar thread brake is shown in EP 3 753 887 A1, in which the thread path passes through a through-hole in the bolt.

[0004] US 5,343,983 A discloses another thread brake. In a first embodiment, two discs are provided which are pressed against each other by a clamping device and which are arranged on a bolt. Thread guide eyes are provided outside the discs, through which a thread path runs. In another embodiment, the discs are mounted in a holder at their outer circumference, and a thread can be guided through an opening in one disc into the space between the two discs.

[0005] The invention relates in particular to a thread brake for use in a warp knitting machine and a warp knitting machine with such a thread brake. The thread brake is used, for example, when the threads have to be unwound individually from spools from a creel. Each thread is subjected to such a thread brake. The thread brakes generate a certain braking force on the thread and thus put it under tension.

[0006] In the field of warp preparation, particularly warping, so-called disc brakes are known. These generate braking force by guiding the yarn between two discs. However, the known disc brakes are comparatively expensive and are therefore not used for warp knitting machines.

[0007] The invention is based on the objective of designing a thread brake in a cost-effective manner.

[0008] This problem is solved in a thread brake of the type mentioned above by arranging the two discs between the disc carrier and a projection on the eyelet carrier, whereby the tensioning device acts with a tensile stress on the eyelet carrier.

[0009] The thread is guided through the thread guide eyelet, thus defining a thread path. This thread path runs between the first and second discs, which are mounted on the eyelet carrier. The eyelet carrier therefore fulfills two functions: firstly, to support the first and second discs, and secondly, to guide the thread. This design requires only a few components: the disc carrier, the two discs, the tensioning device, and the eyelet carrier. These parts can be manufactured and assembled cost-effectively. The tensioning device then generates the braking force via the eyelet carrier.

[0010] Preferably, the projection acts circumferentially around the eyelet carrier at at least two positions on the first disc. This prevents the disc from tilting relative to the eyelet carrier. The projection preferably acts over a surface or at more than two positions on the first disc.

[0011] Preferably, the projection has a recess on its side facing the first disc. The recess facilitates handling, i.e., an operator can easily lift the eyelet carrier from the first disc, which is helpful, for example, for inserting a thread through the thread guide eyelet.

[0012] Preferably, the eyelet carrier is inserted into the disc carrier. This ensures that the eyelet carrier is reliably held in place on the disc carrier.

[0013] Preferably, the eyelet carrier is held securely against rotation in the disc carrier when inserted. This results in a defined direction for the thread path that cannot be changed during operation.

[0014] Preferably, the eyelet carrier can be inserted into the disc carrier in at least two positions. This allows the direction of the thread path to be adjusted. Once the eyelet carrier is inserted into the disc carrier, the angular position is defined.

[0015] Preferably, the thread guide eyelet is made of a ceramic material. A ceramic material is sufficiently resistant to withstand damage from a passing thread. This reliably prevents the thread from getting caught in the loop.

[0016] Preferably, the thread guide eyelet is mounted as an insert in the eyelet carrier. This allows it to be easily replaced without incurring significant costs.

[0017] Preferably, the eyelet carrier is designed as an injection-molded part. This means the eyelet carrier can also be produced cost-effectively.

[0018] Alternatively, the eyelet carrier can be made of a ceramic material. In this case, the thread guide eyelet is preferably integrally connected to the eyelet carrier.

[0019] Preferably, the clamping device has a variable clamping force. By changing the clamping force, the braking effect on the thread running through the thread guide eyelet can be altered.

[0020] Preferably, the clamping device has a clamping element that is arranged between the eyelet carrier and a holding element, wherein the

[0021] The disc carrier has several positions at which the retaining element can be fixed. The position at which the retaining element is fixed determines the extension of the tensioning element and thus the force with which the tensioning element acts on the eyelet carrier. This force, in turn, is crucial for the braking force that the two discs exert on the thread.

[0022] Preferably, the clamping element is designed as an elastomeric tension element or as a coil spring. The elastomeric tension element can, for example, be made of rubber or another elastomeric material. The coil spring can be made of metal or plastic.

[0023] Preferably, the disc carrier has several grooves that run transversely to a clamping direction of the clamping element and in which the retaining element can be fixed. The grooves then form the position at which the retaining element can be fixed.

[0024] The invention is described below with reference to preferred embodiments in conjunction with the drawing. The drawing shows: Fig. 1 is an exploded view of a first embodiment of a thread brake, Fig. 2 is a sectional view of a second embodiment of a thread brake, and Fig. 3 is the thread brake according to Fig. 2 in a perspective view.

[0025] Fig. 1 Figure 1 shows an exploded view of a thread brake 1 with a disc carrier 2, an eyelet carrier 3 into which a thread guide eyelet 4 is inserted, a first disc 5, a second disc 6, a tensioning element 7 and a holding element 8.

[0026] The eyelet carrier 3, with its thread guide eyelet 4, is guided through the first disc 5 and the second disc 6 and inserted into a recess 9 on the disc carrier 2. The eyelet carrier 3 has a polygonal cross-section 10. The recess 9 also has a polygonal cross-section. Therefore, when inserted into the recess 9 of the disc carrier 2, the eyelet carrier 3 is secured against rotation. However, it can be inserted into the disc carrier 2 at two angular positions offset by 90° from each other.

[0027] The clamping element 7 engages at a holding position 11 on the eyelet carrier 3. The clamping element 7 is connected to the holding element 8.

[0028] The disk carrier 2 has several grooves 12 on one side in which the retaining element 8 can be secured. In the present embodiment, the retaining element 8 is designed as a rectangular ring, so that the retaining element 8 can always be arranged in two parallel grooves.

[0029] The clamping element 7 is made of an elastomeric material, for example, rubber. In other words, it can be designed as a rubber band. Alternatively, it can be, as in Fig. 2 It can also be recognized as a spring, in particular as a spiral spring.

[0030] The clamping force generated by the clamping element 7 depends on its elongation. The elongation, in turn, is defined by the position at which the retaining element 8 is attached to the disc carrier 2.

[0031] If the retaining element 8 is positioned further away from the eyelet carrier 3, the clamping force generated by the clamping element 7 increases. If the retaining element 8 is positioned closer to the eyelet carrier 3, a correspondingly lower clamping force and thus a correspondingly lower braking force is generated.

[0032] In total, only seven parts are needed to assemble the thread brake 1. When assembled, the eyelet carrier 3 is inserted into the recess 9 of the disc carrier 2, thus holding the two discs 5 and 6 in position between itself and the disc carrier 2.

[0033] The eyelet carrier 3 has a circumferential projection 13 that acts on the first disc 5. This allows the eyelet carrier 3 to apply force over a surface area while largely preventing the first disc 5 from tilting relative to the second disc 6. The projection 13 has a recess 14 that serves as an ergonomic aid, enabling an operator to grasp the eyelet carrier 3 even when the projection 13 is lying flat against the first disc 5.

[0034] Once the retaining element 8 has been fixed in a desired position on the disc carrier 2, the thread brake 1 generates the desired tension force.

[0035] To thread a thread through the thread guide eyelet 4, the eyelet carrier 3 can be lifted against the force of the tensioning element 7, so that a gap can be formed between the first disc 5 and the second disc 6, through which a thread can be inserted into the thread guide eyelet 4. Since no further thread guide eyelets 4 are required, the complexity of the thread brake 1 is minimized.

[0036] The Figures 2 and 3 show a slightly modified embodiment in which identical elements are provided with the same reference numerals.

[0037] A first modification of the thread brake 1 consists in the fact that the disc carrier 2 has two positions at each of which a thread 15, 16 can be subjected to a braking force. Another difference is that the eyelet carrier 3 is no longer arranged perpendicular to the longitudinal direction of the disc carrier 2, but approximately parallel to the longitudinal direction of the disc carrier 2. Furthermore, the grooves 12 are now no longer arranged on an outer surface of the disc carrier 2, but in a slot 17 in a wall 18 of the disc carrier 2.

[0038] The two brake positions for threads 15 and 16 are identical. Therefore, only the brake position for thread 15 (on the left side of the thread brake in the drawing) is described.

[0039] Finally, the thread guide 3 is formed integrally with the first disc 5. In this case, both the eyelet carrier 3 and the first disc 5 are made of a ceramic material.

[0040] The clamping element 7 is designed here as a spring, specifically a coil spring. The clamping element 7 has an eyelet 19 into which the retaining projection 11 of the eyelet carrier 3 can be hooked. It should be noted that the clamping element 7 has a length that is slightly shorter than the distance between the retaining element 8 and the eyelet carrier 3 in its furthest retracted position on the disc carrier 2, so that the clamping element 7 can exert a small tension on the eyelet carrier 3 in any case.

[0041] If the eyelet carrier 3, the thread guide eyelet 4 and the first disc 5 are formed together as one element, the thread brake only requires five components for each thread.

[0042] As mentioned above, the eyelet carrier 3 can only be inserted into the disc carrier 2 in one or a few angular positions. This can also be used to the advantage of slightly rotating the eyelet carrier 3 relative to the disc carrier 2 after it has been pulled out, thus placing it into an "insertion position." This, in turn, facilitates the insertion of a thread 15 without additional tools and significantly speeds up the insertion or threading process.

[0043] The eyelet carrier 3 and the disc carrier 2 can be produced cost-effectively as injection molded elements.

[0044] The disc carrier 2 can also have a mounting geometry 20, with which the thread brake 1 can be mounted in a frame.

Claims

1. Yarn brake (1) having a first disk (5), a second disk (6), a disk carrier (2) and a tensioning device which applies a force to the first disk (5) in the direction of the second disk (6), the first disk (5) and the second disk (6) being arranged on an eyelet carrier (3), which has a yarn guide eyelet (4) through which a yarn path runs, characterized in that the two discs (5, 6) are arranged between the disc carrier (2) and a projection (13) on the eyelet carrier (3).

2. Yarn brake according to claim 1, characterized in that the projection (13) positions in the circumferential direction around the eyelet carrier (3) acts on the first disc (5) at at least two.

3. Yarn brake according to claim 2, characterized in that the projection (13) has a recess (14) on its side facing the first disc (5).

4. Yarn brake according to one of claims 1 to 3, characterized in that the eyelet carrier (3) is inserted into the disc carrier (2).

5. Yarn brake according to claim 4, characterized in that the eyelet carrier (3) is held in the disc carrier (2) in a non-rotatable manner in the inserted state.

6. Yarn brake according to claim 5, characterized in that the eyelet carrier (3) can be inserted into the disc carrier (2) in at least two angular positions.

7. Yarn brake according to one of claims 1 to 6, characterized in that the yarn guide eyelet (4) is formed from a ceramic material.

8. Yarn brake according to one of claims 1 to 7, characterized in that the yarn guide eyelet (4) is mounted as an insert in the eyelet carrier (3).

9. Yarn brake according to claim 6 or 7, characterized in that the eyelet carrier (3) is formed as an injection-moulded part.

10. Yarn brake according to one of claims 1 to 7, characterized in that the eyelet carrier (3) is formed from a ceramic material.

11. Yarn brake according to one of claims 1 to 10, characterized in that the tensioning device has a variable tensioning force.

12. Yarn brake according to claim 11, characterized in that the tensioning device has a tensioning element (7) which is arranged between the eyelet carrier (3) and a retaining element (8), the disc carrier (2) having a plurality of positions at which the retaining element (8) can be fixed.

13. Yarn brake according to claim 12, characterized in that the tensioning element (7) is designed as an elastomeric tension element or as a spiral spring.

14. Yarn brake according to claim 12 or 13, characterized in that the disc carrier (2) has a plurality of grooves (12) which are arrangeable transversely to a tensioning direction of the tensioning element (7) and in which the retaining element (8) can be fixed.