DE1760458A1 - Process for severing threads underneath spindles and spindle for carrying out the process - Google Patents

Description

Process for severing threads underneath spindles and spindles to carry out the procedure The invention relates to a method for cutting off one on a spindle of a textile machine, preferably one Spinning, twisting or draw twisting machine, subdued thread, and a spindle for Implementation of the procedure.

The rotating construction element of textile machines is under the spindle understood that turns the thread and winds it on a sleeve arranged on it. Under sleeve is any type of carrier for winding bodies, such as conical sleeves, coils or the like understood, which can be plugged onto such spindles and on which threads can be wound in the form of winding bodies. Under threads In the context of the invention, all types of textile threads are understood, for example Yarns, twisted threads or synthetic threads.

In textile machines to which the invention relates, the thread on the spindle is undermined on each spindle after a withdrawal has ended, ie after the winding body wound onto the sleeve has been completed. The thread piece leading from the thread feed mechanism to the underwinding point remains in place during the subsequent tube changing process, so that after the tube changing process has ended, a new winding body can be wound without manually applying the thread coming from the supply mechanism.

In a known spindle of this type, a ring knife is connected to the underwinding point in such a way that the thread leading from the winding body to the underwinding point is automatically cut through between this and the underwinding point when the full sleeve is removed. The underwinding point is freely rotatably mounted on the spindle, the whorl driving the spindle having a slightly smaller diameter than the wharve driving the interwinding point, and both whorls are driven by the same belt. This is intended to ensure that the thread end located on the underwinding point is wrapped around the new tube when the spindle is restarted after the tube changing process has been carried out, so that the underwinding point is free for the next underwinding process. However, this spindle is very complicated, prone to failure and expensive to manufacture. In the spindles used so far in practice, therefore, as a rule, only one separating device is provided for separating the piece of thread leading from the full tube to the underwinding point, to which this piece of thread is applied under tension when the full tube is pulled off and is thereby severed, whereas this is The thread piece wound around the underwinding point is not removed during each take-off, but only from time to time manually when a larger ball of thread has accumulated at the underwinding point. However, manually removing the ball of thread is time consuming. This ball of thread is also often a nuisance. The main object of the invention is therefore to create a method by means of which the aforementioned disadvantages of the known spindles are avoided . In particular, it is an aim of the invention to create a method which enables simple, safe and automatic removal of the thread that has been torn after each tube change process has ended, without the production time of the textile machine in question being lost as a result.

To solve this problem, in a method for severing a thread that is underneath a spindle of a textile machine, preferably a spinning, twisting or stretch-twisting machine, the full tube on the spindle is replaced with an empty one after underneath the thread Sleeve replaced and the underwound thread with a few turns of thread remains at least as long on a main underwinding point until the new thread is wound in at least a few turns on the new tube after the tube changing process , proposed according to the invention that the thread after completion of the full tube is suppressed at spindle speeds that are lower than the operating speed of the spindle and that after the subsequent tube change, the thread windings that have been suppressed are automatically cut when the spindle is restarted. With this method, after the end of each tube change process, when the spindle starts up again, the subdued thread body is automatically severed at at least one point, so that it is thrown away from the spindle by the rotation of the spindle. During the next tube change process, the new thread is then wound onto the empty underwinding point , whereupon the same process is repeated. The piece of thread leading from the full winding body to the underwinding point must be severed every time the tube is changed. In the novel process, this severing can take place in any known manner, for example by applying it to a ring knife arranged on the spindle when the full sleeve is pulled off and thereby cutting it as a result of its own tension. The known cutting devices of this type often have a relatively simple design, but it often happens that this piece of thread is not cut off or is cut too late, for example in that the thread located on the winding body unwinds without tearing, which causes malfunctions.

To avoid this disadvantage is a further development of the novel Procedure provided that during the underwinding process after winding some Thread turns that from the winding body of the sleeve to the main underwinding point leading piece of thread is automatically severed at reduced spindle speed.

The severing of the thread can be done in any suitable manner. It is preferably provided that the severing takes place mechanically and that centrifugal forces are used to control the severing forces required for this, which are generated by the rotation of the spindle. Since the size of the centrifugal forces depends on the spindle speed, the cutting can be controlled by controlling the spindle speed accordingly. In order to carry out the novel method, a spindle for textile machines, preferably spinning, twisting or draw-twisting machines, has to be wound up. a winding body on a replaceable sleeve or the like arranged on the spindle, with a main underwinding point for underwinding a thread and a cutting device for cutting through the undercutting thread, according to the invention it is provided that the cutting device has at least one movably mounted knife which has at least one knife edge, the Hauptunter- crosses on its path of movement windungsstelle, and that the blade as a function of the spindle speed automatically lower between a first main position the spindle speed and a second main position hötser spindle speed (spindle standstill inclusive) adjustable, in which at least one each blade edge of the knife on different sides of the main breakpoint .

The movement of the knife can expediently be controlled by means of centrifugal forces, which are generally advantageously directly applied to the knife and / or parts firmly connected to it or, in some cases, to a control device coupled to the knife, for example a pivoted control device and with the knife motion-coupled conclusive weight, act .and also necessary to cut through cutting forces erzeu- gen and / or tighten cutting forces exerting gückstellmittel. In order to automatically cut through the thread stick leading from the winding body of a full tube to the main underwinding point , it is provided that an auxiliary underwinding point is provided in front of the main underwinding point in the winding direction of the thread to be underwinded and that the cutting device has at least one movably mounted knife, the knife blade of which is at least has a knife edge that crosses the auxiliary underwinding point on its path of movement, and that the knife is automatically adjustable between a first main position of low spindle speed (including spindle standstill) and a second main position of higher spindle speed, in which at least one knife edge of the knife is located different sides of the auxiliary underwinding point.

A particularly simple design of the cutting device is achieved in that at least one knife assigned to the main underwinding point is identical to a knife assigned to the auxiliary underwinding point, which has at least one knife edge that crosses the main and the auxiliary underwinding point at a specific intersection on its path of movement, whereby both crossing points are provided between the two main positions of the knife, and that the knife also has a central position which it assumes in a certain speed range that lies between the spindle speed ranges assigned to the two main positions, the knife blade in its central position being between the two crossing points , whereby at least one knife edge at the transition from the middle position to the first main position and vice versa crosses the auxiliary underwinding point and at the transition from the middle position to the second main position and vice versa di e crosses the main underpass. If the centrifugal force is provided to control the knife movement , the knife is expediently automatic from the first main position to the second main position by centrifugal forces against the action of return means, which in the simplest case can be the knife's own weight, but are preferably spring means adjustable. In this way, a particularly simple and operationally reliable design of the cutting device is achieved.

In general, it is expedient to provide at least two knives , the knife blades of which are arranged in the circumferential direction of the spindle at uniform angular intervals. In this way, a mutual balancing of the knives is achieved at the same time.

Further features of the invention are described or illustrated in the following description, the dependent claims and the drawing, it being understood that the invention can be implemented in numerous further embodiments .

Exemplary embodiments of the invention are shown in the drawing. May Figure 1 is a partially sectioned longitudinally, off 'sectional side view of an inventions to the invention spindle, the details of At some of a type known per se, not shown in all be 2 shows a section through the spindle according to FIG: In the drawings... 1 according to section line II-II in an enlarged illustration, FIG. 3 a partial section through the spindle according to FIG. 2 according to section line III-III in an enlarged illustration, FIG. 4 an enlarged side view of a knife spring of the spindle according to FIGS. 1-3, 5 shows a partial longitudinal section through a novel spindle according to a further exemplary embodiment of the invention, FIG. 6 shows a partial longitudinal section through a spindle according to a third exemplary embodiment of the invention, FIG. 7 shows a section through the spindle according to FIG. 6 along section line VII-VII. In the drawing, corresponding parts are provided with the same reference numerals.

The spindle 1 shown in FIGS. 1-3, which is rotatably supported in a bearing housing (not shown) and is driven by means of a belt (not shown) resting on its whorl 2, has a spindle shaft 3, a collar 4 fixed on this and a conical one Sleeve carrier 5 on. A conical sleeve 6 is plugged onto the sleeve carrier 5 , the foot of which is seated in an annular, axial recess 7 of the collar 4. On the sleeve 6 there is a winding body B. The collar 4 has a concave bulge 9 and an auxiliary 10, the auxiliary 10 is behind the main 9 and is designed as a rear engagement. Between the two underwinding points 9, 10 an annular, knurled thread deflection element 11 is provided for the thread leading from the auxiliary underwinding point to the main underwinding point. The knurling prevents this thread section from being displaced in the circumferential direction of the spindle.

In the lower half of the collar 4, a total of four radial slots 12, each offset by 900 relative to one another, relatively wide slots 12 are provided, each of which penetrates the relevant wall of the collar 4 completely and extends beyond the auxiliary underwinding point 10. In the lower end of the collar 4. An annular, inner recess 13 is provided in which a total of four identically designed knife springs 14 are arranged, one end 15 of which is firmly clamped, and the free, angled, straight ends as double-edged knives 16 with triangular knife blades 17 are formed which can engage in the radial slots 12 ,. The shape and location of these knives springs is particularly clear from FIG. 2 to detect. A side view of such a knife spring 14 is shown in FIG. As can be seen, each knife spring is angled upwards at 18 and 19, so that in the illustration according to FIG. 2 they partially overlap but do not touch. Each knife spring has an S-shaped bent center piece 20, the arch of which is clamped adjacent to the clamping point in the annular gap between a lower ring segment 21 of the collar and the spindle shaft 3, while the other arch rests only on the ring segment 21. Four permanent magnets 22 are firmly inserted into the ring segments at mutual angular distances of 90 ° in the manner shown, each of which interacts with a knife spring. In the spindle shaft 3, four permanent magnets 23 are also inserted at angular intervals of 90 °, the outer pole faces of which interact with an associated knife spring, specifically with its kink 25. The knife springs 14 are made of ferromagnetic material.

Each knife 16 can be in the slot 12 in which it is located depending on the centrifugal force acting on it during the rotation of the spindle between the first main position 33, which is fully extended in FIG. 1, and that at 24 indicated second main position back and forth. In the first main position 33, which occurs at very low spindle speeds and when the spindle is at a standstill, the kink 25 adheres to the associated magnet 23, causing a premature Lifting off of the knife 16 is prevented. Each magnet 22 acts on the associated knife spring 14 at a distance from its clamping point and the knife 16, which causes the knife to move out of its @ second when the spindle speed is reduced Main position initially only in a middle position indicated at 26 in FIGS. 1 and 2 moves, in which it is disengaged between the two Unterwindungsstellen with these is located, however, the knife spring in question continues to be attached to the magnet 22 is liable. Only overcome if the spindle speed is significantly reduced again the spring force of the knife spring the adhesive force of the magnet 22, so that through these the middle position 26 of the individual knife over a wide speed range adjusts. Instead of the magnets 22, mechanical means can optionally also be used be provided for the same purpose, for example, the knife spring on a Curve as an abutment come to rest in such a way that the width of the middle position assigned speed range is increased. Or it can be the same or similar effect through suitable impressions of those interacting with the knife Feather can be achieved, this impression and the feather shape so met are that the spring in a bending direction up to a certain position like a conventional spring can be bent, but with increasing bending force essentially stops in this position and only when a greater specific bending force jumps into a new position. In the opposite direction of bending Essentially the same process takes place. This spring is essentially referred to as a bistable spring. Also other bearings of the knife that provide stabilization the middle position, _are conceivable. The cutting edges 27, 28 of the spring have a razor blade so that the threads are already with low cutting force. The cutting force is achieved by pulling Cutting and even further due to the vibrations that occur when the spindle rotates reduced.

l On his way from the first main position 33 to the second main position 24 crosses the single knife 16 first in a low spindle speed range the auxiliary underwinding point 10 and, at a certain higher speed, the main underwinding point 9. When the spindle speed decreases, the reverse process takes place. As a result the double-edged, triangular design of the knife blade is on everyone A pulling thread that lies in the area of the knife path in the underwinding points Cut made in both directions of movement of the knife. How this works Spindle is as follows: After completing a full sleeve 6, 8 the spindle speed is the operating speed at which the knife is in its second main position is located, lowered so far that each knife assumes the central position 26. Now the thread 29 is undermined and first a thread section into the auxiliary underwinding point 10, which only needs to be long enough to be one of the four radial slots 12 bridged. Then the thread is over the ring-shaped thread deflection point 11 inserted into the main underwinding point 9 and in several thread windings (Fig. 3) subdued. During this process, this is done in the auxiliary underwinding point located Thread section 31 (Fig. 3) through the illustrated cross-sectional shape the auxiliary underwinding point in connection with the knurling of the deflection point 11 held. The spindle 1 is then stopped, whereby all knives 16 get into their first main position 33, and this in the auxiliary underwinding point Cut 10 straight thread, so that afterwards the full tube can be made without difficulty can be withdrawn from the spindle. After the end of the case change process the spindle is driven again. The delivery plant, not shown, to the The thread which leads to the main underwinding point and is denoted by 32 in FIG. 1 lies down here - taken by the knurling of the deflection point 11 - with a partial turn into the underwinding point. When a certain spindle speed is exceeded the knives 16 detach from the magnets 23 and first cut through the new one thread inserted in the auxiliary underwinding point. At this point in time are dreadful a few turns of thread wound on the new tube. The speed is increased further, whereby the knives 16 come into their second main position 24 and on their path of movement cut through the thread turns lying in the main underwinding point 9. the cut pieces of thread are removed from the area of the by the centrifugal force Spindle thrown out.

In the spindle shown in FIG. 5, a sleeve carrier 41 is arranged on the spindle shaft 40, onto which a sleeve 42 is slipped. A collar 43 adjoins the sleeve carrier in one piece with the latter and is provided with a slot 44 which penetrates it completely. The slot 44 has a rectangular cross-section. In it, two knives 45 are pivotably mounted in a radial plane symmetrically to the axis of the spindle shaft. The knife's center of gravity lies above the pivot axis, so that the centrifugal forces acting on the knives pivot them against the action of the leaf springs 46. The leaf springs 46 serving as restoring means press the knives at low speeds or at a standstill of the spindle into a first main position 50 in which the knife blade 47 is located in the area of the auxiliary underwinding point 48 formed as a convex triangular cross-section. Axially below the auxiliary underwinding point 48 there is an identically designed main underwinding point 49. The knife blade 47 is triangular with cutting edges 51, 52 and is designed and arranged in such a way that it is located between the auxiliary and main underwinding point in the middle position shown in full line in FIG. without interfering with them. The knife can assume this central position in a certain speed range. When this speed range is exceeded, the knife moves into the second main position 53 as a result of the centrifugal force acting on it. The knife maintains this main position even when the operating speed is reached. The mode of operation of this spindle is as follows: After a full sleeve has been completed, the spindle speed is reduced to the speed assigned to the middle position of the knife 45. The thread is then undermined and at least half a thread turn is initially placed in the auxiliary underwinding point 48 and then a few more thread turns are placed in the main underwinding point 49. In order to prevent the thread turns from shifting, the annular thread deflection point provided between the two underwinding points is knurled. After the underwinding process has been carried out, the spindle is stopped, each knife being pressed into its first main position 50 by the action of the leaf spring 46 and thereby cutting the thread located in the auxiliary underwinding point 48 so that the full tube can then be pulled off without difficulty. After inserting a new empty tube, a few turns of thread are first wound onto the empty tube at a low spindle speed and then the spindle speed is increased up to the operating speed, whereby the knife moves from its first main position 50 via the middle position into the second main position 53 and all in the underwinding points 49, 48 cuts through the lying thread turns, so that the thread pieces in question are thrown away from the spindle by the centrifugal force.

In the example shown in Figs. 6 and 7 embodiment a collar is fixed on the spindle 61 shaft 60, which is formed similarly to the collar according to Fig. 4. The auxiliary underwinding point is designated by 62 and the main underwinding point by 63. Instead of a continuous radial slot, this collar has a total of four slots 64 offset from one another by 900 each.

On the spindle shaft, a knife device 65 is straight out in a bore 66 of the collar, which has four radially aligned knives 67 with triangular knife blades, each of which is located in one of the four slots 64. When the spindle is stationary or at low spindle speeds, the helical spring 68 serving as a restoring means presses the cutter device 65 into the upper position shown in dash-dotted lines. A centrifugal device 69 engages the measuring device 65, which has two weights 70 which are mounted longitudinally displaceably in radial bores of the collar and which are each connected to the knife device 65 via a cord-shaped traction device 71, which is guided over a rotatably mounted roller 72 . The mode of operation of this device is as follows: At operating speeds of the spindle, the cutter device 65 is in the second main position 73 due to the centrifugal force acting on the weights fully extended middle position. At this spindle speed, as in the exemplary embodiment according to FIG. 5, the thread is undermined. The spindle is then stopped, whereupon the knife device 65 moves into its first main position 74 through the action of the helical spring 68 and in the process cuts through the thread lying in the auxiliary underwinding point 62. When the spindle starts up again, the knife device 65 returns to the second main position 73 and cuts through the thread windings located in the main underwinding point 63, so that the thread pieces that hit are flung away from the spindle.

Claims (5)

Claims --------------- 1. A method for severing a thread on a spindle of a textile machine, preferably a spinning, twisting or draw-twisting machine, in which, after the thread has been wound underneath, the The full tube located on the spindle is exchanged for an empty tube and the underneath thread with a few turns of thread remains on a main undulation point at least until the new thread is wound in at least a few turns on the new tube after the tube changing process has been completed, characterized in that the Thread is undermined after completion of the full tube at spindle speeds that are lower than the operating speed of the spindle and that after the subsequent tube change, the undermined thread turns are automatically cut when the spindle is restarted. 2. Procedure according to Claim 1, characterized in that after the end of the sleeve changing process when the spindle is restarted, at least those on the main underwinding point Thread windings are severed at spindle speeds that are greater than the spindle speeds which were undermined before the sleeve was changed. 3. The method according to claim 1 or 2, characterized in that during the underwinding process after winding some turns of thread that of the winding body of the Sleeve too The piece of thread leading to the main underwinding point automatically at reduced spindle speed is severed. 4. The method according to any one of the preceding claims, characterized characterized in that the thread is severed mechanically and that for Controlling the separation processes centrifugal forces are used by the rotation the spindle arise. 5. Spindle for textile machines, preferably spinning, twisting or stretch twisting machines, for winding a winding body onto an exchangeable sleeve or the like arranged on the spindle, with a main underwinding point for undercutting a thread and a cutting device for cutting through the undercutting thread for carrying out the method according to one of the preceding claims, characterized in that the cutting device has at least one movably mounted knife (16) which has at least one knife edge which crosses the main underwinding point (9) on its path of movement, and that the knife automatically switches between a first main position (33) lower spindle speed (including spindle standstill) and a second main position (24) higher spindle speed can be adjusted, in each of which there is at least one knife edge of the knife on different sides of the main underwinding point. 6. Spindle according to claim 5, characterized in that an auxiliary underwinding point (10) is provided in the winding direction of the thread to be underwinded in front of the main underwinding point (9-) and that the cutting device has at least one movably mounted knife (16), the knife blade of which has at least one knife edge which crosses the auxiliary underwinding point on its path of movement, and that the knife is automatically adjustable between a first main position (33) of lower spindle speed (including spindle standstill) and a second main position (24) of higher spindle speed, in each of which at least one The knife edge of the knife is on different sides of the auxiliary underwinding point (10). 7. Spindle according to claim 6, characterized in that at least one of the main underwinding point (9) associated knife (16) is identical to one of the auxiliary underwinding point (10) associated knife, which has at least one knife edge, the main and the Auxiliary underwinding point crosses at a specific crossing point, both crossing points being provided between the two main positions of the knife, and that the knife furthermore has a central position (26) which it assumes in a certain speed range which is between the two main positions (24, 33 ) assigned spindle speed ranges, with the knife blade in its middle position between the two crossing points, whereby at least one knife edge crosses the auxiliary underwinding point (10) when transitioning from the middle position (26) to the first gauging position (331 and vice versa) and when transitioning from the middle position for the second main statement (24) and vice versa the main underwinding point (9) crosses. B. spindle according to one of claims 5 - 7, characterized in that the knife (16, 67) by means of centrifugal forces occurring during spindle rotation against the action of restoring means (14, 23; 68) from the first main position to the second main position automatically is adjustable and that these centrifugal forces preferably act on the knife and / or parts (70) connected to it. 9. Spindle according to one of claims 5-8, characterized in that the main underwinding point (9) is designed as an annular, concave bulge of a collar (4). 10. Spindle according to one of claims 6-9, characterized in that the auxiliary underwinding point (10) is designed as an annular, concave bulge of a collar (4). 11. Spindle according to one of claims 6-10, characterized in that the auxiliary underwinding point (48) is arranged axially above the main underwinding point (49). 12. Spindle according to claim 10, characterized in that the flilfsunterwindungsstelle (10) is provided in a flintergritt behind the flauptunterwindungsstelle (9). 13. Spindle according to one of claims 5 - 12, characterized in that at least part of the path of movement of the knife runs in a radial slot (12) of a collar 9) having the underwinding point or underwinding points (9, 10), and the undercutting thread runs this slot crosses, as a result of which a safe cutting of the underneath thread is achieved. 14. Spindle according to one of claims 5-13, characterized in that at least two knives (16) are provided, the knife blades of which are arranged in the circumferential direction of the spindle at uniform angular intervals. 15. Spindle according to one of claims 5-14, characterized in that the knife (16) is double-edged: 16. Spindle according to one of claims 5-15, characterized in that the knife blade (17) is approximately triangular. 17. Spindle according to one of claims 5-15, characterized in that at least one cutting edge (27, 28) of the knife (16) is designed in this way; that through them, when the knife blade is moved, the undercutting thread can be cut through while pulling. 18. Spindle according to one of claims 5-17, characterized in that the knife (16) is resiliently mounted. 19. Spindle according to one of claims 5-17, characterized in that the knife (45) is mounted pivotably about a pivot axis. 20. Spindle according to claim 18, characterized in that the knife (16) is designed as a free end piece of a spring (14) causing the resilient mounting. 21. Spindle according to one of claims 5 - 20, characterized in that the path of movement of the knife runs in an approximately radial direction of the spindle @. 22. Spindle according to one of claims 5-21, characterized in that a permanent magnet device (22, 23) is provided which exerts a holding force on the knife (16) in at least one position, which is, however, caused by the restoring means (14) or the centrifugal force acting on the knife can be overcome. 23. Spindle according to claim 22, characterized in that at least one permanent magnet (22) cooperates with a spring (14), at one end of which the knife (16) is arranged, the magnet acting on the spring at a distance from its clamping point and the Knife acts to stabilize a central position. 24. Spindle according to one of claims 5-23, characterized in that the knife cooperates with bistable spring means, the jump point of which lies at least in one direction of movement of the knife in the region of its central position to stabilize it.