Title of Invention

DEVICE FOR SPINNING OR TWISTING LOOPS

Abstract

Disclosed is a device for spinning or twisting loops, essentially comprising a vertical spindle (4) and balloon limiter (7) that is disposed co-axial to the spindle (4) and feeds the yarn (P) to a sleeve (5) which is mounted on the rotating spindle (4). The balloon limiter (7) consists of o top part (13) that is driven in the same direction of rotation as the spindle (4) and a non-rotatable bottom part (14, 14a) which adjoins said top part (13) in a cotactless manner. The bottom part (14, 14a) is provided with a guiding area (22, 22a) for the yarn (P), which begins at the interior face thereof and ends at the bottom face thereof

Full Text

Technical Field This invention relates to a device for loop spinning or twisting comprising a substantially vertical spindle and a balloon limiter arranged coaxially to the spindle for feeding the yarn to a tube mounted on the rotating spindle. State of the Art The device mentioned above is one of the variants of a device for loop spinning or twisting according to Patent Specification EP 883703 B. The balloon limiter, which takes the form of a one-piece tube and is provided with an enlargement at its lower end, is in this case rotatably mounted and is driven in operation in the same sense as the spindle. In operation, the yarn being forwarded is forced by centrifugal force to travel along its inner surface from which, under the effect of the winding tension, it passes directly to the sleeve mounted on the rotating spindle. As a result of the rotation of the balloon limiter and the spindle, the yarn is forced to rotate around the longitudinal axis of the spindle, so that in transfer from the inner surface of the balloon limiter to the sleeve it forms a rotating open loop which rotates immediately below the lower end of the balloon limiter, this end also being referred to as the exit end, the loop controlling the yarn tension in a manner similar to the traveller of a ring spinning or ring twisting device. In order to maintain the open rotating loop continuously at an advantageously lower rate of revolutions than the spindle, its rotation should be braked. According to the above-mentioned patent specification, this is achieved, for example, by means of a non-movable limiting wall for limiting the size of the open loop in the radial direction, this wall enclosing and partially overlapping the exit end of the balloon limiter with a predetermined spacing, the reversing bend of the rotating open loop coming into contact with the wall, and/or by means of a guide edge for the yarn being wound, the edge also being non- movable and being arranged underneath the balloon limiter around the longitudinal axis of the spindle, the lower leg of the rotating open loop coming into contact with the guide edge in travelling to the sleeve. On devices of this kind it is possible to produce quality yarns with high speed. However, increased friction between the rotating open loop and the limiting wall has to be taken into account; this can lead even to mutual damage. For several kinds of yarn, in particular those made of thermoplastic fibres this fact can however represent a limitation, which has not yet been fully overcome even with the use of a limiting wall having a low-friction surface extending away from the longitudinal axis of the spindle from the region of first contact with the yarn in the direction to the lower end (EP 933 454): Furthermore it has proved to be the case that any contact between the reversible bend of the rotating open loop and the limiting wall unfavourably increases the yarn tension. During braking of the rotating open loop by means of a guide edge arranged under the balloon limiter and affecting the lower leg of the rotating open loop, it must also be expected that relative rotation occurs between the guide edge and the reciprocating spindle causing regularly repeating changes in the magnitude of the wrap of the yarn on the guide edge and a consequent variation in the yarn tension. Even if this variation in tension is not large, it can, in many cases, especially in production of finer yarns, cause damage and thus limit the range of use of this device. If a guide edge is used alone for braking the rotating open loop, then not only the above-mentioned tension variations have to be expected, but also that at high working speeds a corresponding centrifugal force arising between the balloon limiter and the guide edge that brakes the yarn can cause an unacceptable increase in the radial extent of the rotating open loop and consequent unclesired drawing of the yarn. In this case also, there are limitations that affect several yarns. Essence of the invention The object of the invention is to design the above-described device in such a way that it enables production of quality yarn at high operating speed without the above-mentioned limitations. This object is achieved in accordance with the invention in that the balloon limiter comprises an upper portion drivable in the same sense of rotation as the spindle, and a non-rotatable lower part adjoining the upper part without contact, the lower part having a guide surface for the yarn starting at its inner face and ending at its lower end face. As a result of this arrangement a completely freely rotating loop is created immediately below the non-rotatable part of the balloon limiter, the rotation of this loop being braked in an expedient manner by means of a guide surface on the non- rotatable part of the balloon limiter and the loop thereby being able to control the yarn tension all by itself. The braking effect of the guide surface on the non-rotatable lower part of the balloon limiter is also positive in that - in combination with the winding tension - the required functional size of the rotating open loop is maintained in the radial direction so that no other measures are needed for this purpose. On this device, therefore, various kinds of yarn can be produced at the present time without the previously unavoidable limitations. Furthermore, it has been established that non- rotatable lower part of the balloon limiter, these yarns exhibit a better arrangement of the outer fibres so that the yarns are of higher quality, especially as regards hairiness. It has also proved to be the case, that the working speed can be increased still further because in the rotatable upper part of the balloon limiter, in comparison to the earlier one-piece balloon limiter, the radial loading is lower, such that the component of centrifugal force, which in the case of the one-piece balloon limiter acts by way of the rotating open loop with full weight on the exit end thereby tending to shift this exit end from the longitudinal axis, is now taken up at least in part by the non-rotatable lower part of the balloon limiter. Further advantageous embodiments of the invention are set out in the dependent claims. Description of the figures of the accompanying drawings Embodiments of the invention are represented schematically in the attached drawings. In Fig. 1 an embodiment of the device according to the invention is illustrated I side view, Fig. 2 shows a part taken from Fig. 1 and in Figure 3 a partial view of another example of the device according to the invention is shown. Description of the embodiments In Fig. 1 only one of the devices for loop spinning or twisting is shown. In a corresponding machine a large number of such devices can be provided as operating positions on one or on each longitudinal side. These devices comprise a drafting arrangement for the fibre sliver or roving, or a feed device for multiple thread ends depending whether the device is for loop spinning or loop twisting. From the viewpoint of the invention these devices each comprise a feed device 1 for the fibre material 2 to be spun or twisted. The spindle 4 with the sleeve 5 and yarn package 6 is arranged vertically below the feed device 1, which in Fig. 1 is shown as a pair of delivery rolls 3; there is also a balloon limiter 7 for feeding the yarn P to the sleeve 5 on the rotating spindle 4 Between the feed device 1 and the balloon limiter 7 there is a yarn guide 8 for directing the yarn P into the longitudinal axis of the balloon limiter 7 or spindle 4. In another example (not illustrated) of an embodiment of the invention, the feed device itself can be used for directing the yarn in this way, being so arranged, for example, for this purpose that the lower delivery roll takes the place of the yarn guide thereby replacing it completely. The spindle 4 is formed as a rotor of an electric motor mounted on a spindle bank 11. The spindle bank 11 extends over all operating positions of the machine and, for the purpose of building a new yarn package 6, is provided with the usual program-controlled drive (not illustrated) for its rising and falling movements in the direction of the double-headed arrow 12. Alternatively, the spindle can, of course, also be mounted rotatably in a known manner in a similar spindle bank, the rotation being derived from a tangential belt, which also extends over all operating positions of the machine (not shown). The balloon limiter 7 consists of an upper part 13 and a lower part 14 adjoining the upper part without contact. The upper part has, for example, the form of a bell or bottle, providing a continuous surface 15 for contact with the yarn P and widening conically in a direction towards the exit end 16. The convergent, part of the side of the entry end 17 forms a shaft 18 by means of which this part is rotatably mounted in a bearing block 19 and is driven by an asynchronous electric motor 20. The bearing block 19 and the motor 20 are arranged in a housing, which is secured to the carrier rail 21 as will be disclosed in greater detail below. The carrier rail 21 extends over all operating positions of the machine, as does the spindle bank 11, but differs from the spindle bank 11 in that it does not move. The lower part 14 of the balloon limiter 7 (see Fig. 2) has the form of a ring 26 and is associated with the exit end 16 of the upper part 13 at its end face. This part 14 has a rotational guide surface 22 for the yarn P, starting on its inner face and ending on its lower end face. In this embodiment the guide surface 22 is alternatively curved in the direction of the longitudinal axis 9 of the balloon limiter 7 or the spindle 4, the smallest diameter A - measured in the plane at right angles to the longitudinal axis of the balloon limiter 7 or spindle 4 - being smaller than the largest diameter B of the inner surface 15 of the upper part of the balloon limiter 7. The guide surface 22 has the form of a stepless curve, but if necessary it can take another form, e.g. as a part of the outer surface of a foldable capsule. The whole lower part 14 of the balloon limiter 7, or at least that part thereof that comes into with the yarn, can be made out of commercially available tool steel, either by machining or by precision moulding, or by swaging with subsequent fine polishing of the guide surface 22. For the purpose of increasing operating life, at least the guide surface 22 could be made out of a material especially resistant to wear, e. g. technical ceramic. For the purpose of maintaining a fixed positional relationship between the upper part 13 and the lower part 14 of the balloon limiter 7 (Fig. 1), the lower part 14 is mounted within a holder 23, for example, by means of a screw fastening or also by means of a clamp connection described below by reference to Figure 3 etc. The holder encloses the balloon limiter 7 like a tube, that is both its upper part 13 and its lower part 14, and is secured at its upper end to the carrier rail 21, this holder also forming the housing of the bearing block 19 and the motor 20 in the upper part 13 of the balloon limiter 7. In operation, the upper part 13 of the balloon limiter 7 is driven in the same sense as the spindle 4 with the winding sleeve 5 and the yarn package 6 (Fig. 1 and 2). The yarn P, which is fed to the sleeve 5 or to the yarn package on this sleeve 5 by way of the balloon limiter 7, is forced because of the centrifugal force to travel first along the internal surface 15 of the rotating upper part 13 of the balloon limiter 7, thereafter being guided along the guide surface 22 of its non-rotatable lower part 14 directly to the sleeve 5 or onto the package. As a result of the rotation of the upper part 13 of the balloon limiter 7 and the spindle 4 the yarn P is forced to rotate also around the longitudinal axis 9 of the spindle 4, so that in passing from the lower part 14 of the balloon limiter 7 onto the sleeve 5 or the yarn package 6 it forms a rotating open loop Ps, which rotates immediately below the lower part 14 of the balloon limiter (Fig. 2). Because the open loop Ps is completely free it controls the yarn tension itself, so that in reaction to the changes in the diameter of the yarn package 6 the magnitude of the tension changes in the radial direction, and thus also the magnitude of the centrifugal force acting thereon. The centrifugal force acting on the rotating open loop Ps supports also in a useful manner the movement of the yarn P over the guide surface 22 of the non-rotatable parti 4 of the balloon limiter 7. At the same time, this guide surface 22 also acts as a brake on the rotating open loop Ps so that by this means also the rotating open loop Ps is braked in its rotation around the longitudinal axis 9 of the balloon limiter 7 and spindle 4 in such manner that its speed of rotation is advantageously lower than the speed of rotation of the spindle 4. The braking effect of the guide surface 22 does not have to be particularly large because for the required reduction of speed of the rotation of the rotating open loop Ps it suffices if only a small portion of the kinetic energy is absorbed by friction on the guide surface 22. Furthermore, by this kind of braking, in combination with the winding tension, the functional size of the rotating open loop Ps is maintained in the radial direction. During winding on the sleeve 5, the yarn P is guided along the sleeve 5 onto the yarn package 6 by means of the usual program controlled up and down movement of the spindle bank 11 in the direction of the double-headed arrow 12 . In the illustrated embodiment, the smallest diameter A of the guide surface 22 of the lower part 14 of the balloon limiter 7 is smaller than the largest diameter B of the inner surface 15 of the upper part of the balloon limiter 7. Due to this, the component of the centrifugal force acting on the rotating open loop Ps on the side of the balloon limiter 7 is taken up by the non-rotatable lower part 14 of the balloon limiter 7, and the upper part 13 of the balloon limiter 7, which is subject to only slight radial loading, manages with a power input which is sufficient to maintain the given operating speed. Since the upper part 13 of the balloon linniter 7 is also not subjected at its exit end 16 to strong friction from the yarn P, this part 13 can be made of a very light material, which is less resistant to wear from the yarn, e. g. Duraluminium, or of a suitable technical plastics material, which is comparatively cheap and easy to work. A design of this type gives lower mass of the upper part 13 of the balloon limiter 7 and improves its dynamic performance insofar as its harmonic frequencies are shifted to higher operating rates of revolution.The bearing block 19, in which the shaft 18 of the upper part 13 of the balloon limiter is mounted, is then only loaded by the mass of its own rotating body; this is advantageous from the point of view of its lifespan. Another embodiment of the invention is partially illustrated in Fig. 3, where it is assumed that the other elements not shown in Fig. 3 are identical with the elements shown in Fig. 1. As shown in Fig. 3, the lower part 14a of the balloon limiter 7 takes the form of a part of a cylindrical tube, this part 14a coaxially enclosing and partially overlapping the upper part 13 of the balloon limiter with a spacing that enables free movement. This part 14a also has a guide surface 22a similar to the lower part 14 of the balloon limiter according to Fig. 1 and 2. However, the guide surface 22a begins on the inner face as an internal cylindrical surface and ends on the lower end face as an adjoining rounded end of the tube. This part 14a is movably mounted in a holder 23a, which, as regards its design, corresponds to the holder 23 for the lower part 14 of the balloon limiter according to Fig. 1. The only difference lies in the fact that its lower end carrying the the lower part 14a of the balloon limiter 7 is formed al an elongated, slotted clamping sleeve with radially projecting end brackets 24 to enable drawing together by means of a screw 25 or another known tightening element. Of course, the holder 23 carrying the lower part 14 according to Fig. 1 can also be arranged in the same way. In any event, the possible arrangements and kinds of fixing for the lower part 14, 14a of the balloon limiter 7 in the holder 23, 23a are not thereby exhausted. It is important in each case to find a mode which ensures a fixed positional relationship between the lower and upper part of the balloon limiter 7 and at the same time enables both exchange of one lower part of the balloon limiter for another, which, for example, is adapted to another kind of yarn or yarn fineness, and also axial setting of the exit end 26, 26a of the lower part 14, 14a of the balloon limiter 7 relative to the exit end 16 of the upper part 13 of the balloon limiter 7 so far as this is necessary. Index of reference numerals 1. Feed device 2. Fibre material 3. Delivery roll 4. Spindle 5. Sleeve 6. Yarn package 7. Balloon limiter 8. Yarn guide 9. Longitudinal axis 10. Electric motor 11. Spindle bank 12. Double-headed arrow 13. Upper Part 14. and 14a Lower Part 15. Surface 16. Exit end 17. Entry end 18. Shaft 19. Bearing block 20. Motor 21. Carrier rail 22. Guide surface 23. Holder 24. End bracket 25. Screw 26. and 26a Exit end of the lower part P Yarn Ps Loop A smallest diameter B largest diameter We Claim: 1. Device for loop spinning or twisting comprising a substantially vertical spindle (4) and a balloon limiter (7) arranged coaxially with the spindle (4) for feeding the yarn (P) to a sleeve (5) mounted on the rotating spindle (4), characterised in that the balloon limiter (7) comprises an upper part (13) driven in the same sense of rotation as the spindle (4) and a non-rotatable lower part (14, 14a) adjoining the upper part without contact, the lower part (14, 14a) having a guide surface (22, 22a) for the yarn (P) which starts on its inner face and ends on its lower end face. 2. Device according to claim 1 wherein the lower part (14, 14a) of the balloon limiter (7) is made of a wear- resistant material at least on the guide surface (22, 22a). 3. Device according to claim 1 or claim 2 wherein the guide surface (22) is curved in a direction radial to the longitudinal axis (9) of the spindle (4), its smallest diameter (A) - measured in a plane at right angles to the longitudinal axis (9) of the spindle (4) - being at the most equal to the largest diameter (B) of the inner surface (15) of the upper part (13) of the balloon limiter (7). 4. Device according to one of claims 1 to 3 wherein the lower part (14, 14a) of the balloon limiter (7) is provided with a holder (23, 23a) by means of which it is mounted for adjustment in an axial direction relative to the upper part (13). 5. Device according to claim 4 wherein the holder (23, 23a) forms part of the bearing and motor housing of the upper part (13) of the balloon limiter (7). Disclosed is a device for spinning or twisting loops, essentially comprising a vertical spindle (4) and balloon limiter (7) that is disposed co-axial to the spindle (4) and feeds the yarn (P) to a sleeve (5) which is mounted on the rotating spindle (4). The balloon limiter (7) consists of o top part (13) that is driven in the same direction of rotation as the spindle (4) and a non-rotatable bottom part (14, 14a) which adjoins said top part (13) in a cotactless manner. The bottom part (14, 14a) is provided with a guiding area (22, 22a) for the yarn (P), which begins at the interior face thereof and ends at the bottom face thereof

Documents:

1909-kolnp-2005-granted-abstract.pdf

1909-kolnp-2005-granted-claims.pdf

1909-kolnp-2005-granted-correspondence.pdf

1909-kolnp-2005-granted-description (complete).pdf

1909-kolnp-2005-granted-drawings.pdf

1909-kolnp-2005-granted-examination report.pdf

1909-kolnp-2005-granted-form 1.pdf

1909-kolnp-2005-granted-form 18.pdf

1909-kolnp-2005-granted-form 2.pdf

1909-kolnp-2005-granted-form 26.pdf

1909-kolnp-2005-granted-form 3.pdf

1909-kolnp-2005-granted-form 5.pdf

1909-kolnp-2005-granted-reply to examination report.pdf

1909-kolnp-2005-granted-specification.pdf