EP1254066A1

EP1254066A1 - Method for feeding a thread in a twist-free manner and thread feeding device

Info

Publication number: EP1254066A1
Application number: EP01905759A
Authority: EP
Inventors: Sture Persson
Original assignee: Iropa AG
Current assignee: Iropa AG
Priority date: 2000-02-11
Filing date: 2001-02-09
Publication date: 2002-11-06
Anticipated expiration: 2021-02-09
Also published as: DE50103218D1; EP1254066B1; CN1400953A; US6726139B2; US20030122018A1; WO2001058794A1; DE10006142A1; CN100347061C

Abstract

The invention relates to a thread that is fed to a textile machine in a twist-free manner and has a band-like character. The thread is taken from a stock in a twist-free manner and is mounted on a stationary storage drum in a thread feeding appliance having a rotatable central shaft and a winding element which protrudes therefrom and towards the outside. Said thread is supplied to the textile machine in an overhead manner and by means of the storage drum. During operation of the thread feeding appliance, functional twists are produced in the thread only during transition from the central shaft into the winding element. Said twists are inhibited from being transported back against the thread path direction and, together with the thread, are regularly conveyed to the storage drum in almost perfect match with the rotations of the central shaft. At least one sliver guide gap (G) that is stationary in relation to the central shaft is provided in the thread feeding appliance (F) and along the thread path in the central shaft (S, 4) in the area of transition (7) of the central shaft into the winding element (W).

Description

Process for the twist-free delivery of a thread and thread delivery device

The invention relates to a method according to the preamble of claim 1 and a thread delivery device according to the preamble of claim 3.

In a method known from EP 0 396 902 A (US Pat. No. 5,069,395 A), the thread is fed from a supply spool to the thread delivery device without twist, in that the supply spool is rotated in accordance with the thread speed in the thread delivery device. In the thread delivery device, the thread runs through the hollow central shaft and the winding element standing outwards from it, before it is deposited in adjacent turns on the storage drum. From the textile machine, the thread is first drawn inwards from the thread winding over the head of the storage drum with the circumferential thread take-off point and then further axially. Depending on the function, a twist in the thread occurs with every rotation of the central shaft, ie a twist of 360 ° in the direction of rotation of the central shaft. When a complete turn is withdrawn from the storage drum, a twist, ie a rotation of 360 °, is also generated, however in the opposite direction of rotation. Thus, every twist generated during winding would have to be removed again when pulling off and the thread would run into the textile machine without twist. However, the transition from the central shaft to the winding element represents a mechanical obstacle in the thread travel path. Since the thread is supported on the storage drum and the winding element rotates relative to the circumference of the storage drum, the winding element generates a tension in the thread. Among other things, under the influence of the tension in the belt, the obstacle shows a phenomenon that disturbs the balance between the twists generated and the twists released during unwinding. This is because not every twist generated is immediately conveyed further, but there is occasionally a jam of one or more twists at the transition, which may even reverse in the opposite direction to the thread running direction, and the obstacle is delayed and / or passed in groups of several. This means that if there is no twist in one turn on the storage drum, a twist in the opposite direction is generated in the opposite direction and is entered into the textile machine, or that if there are several twists in the turn on the storage drum, only one twist is released and the remaining in the textile machine. Despite the High expenditure for twist-free feeding of the thread from the supply into the thread delivery device then twist-related fabric defects and malfunctions cannot be avoided.

The invention is based on the object of specifying a method of the type mentioned at the outset and a thread delivery device which is suitable for carrying out the method and with which fabric defects and malfunctions by twists are avoided.

The object is achieved with the features of claim 1 and the features of the independent claim 3.

According to the method, each twist generated is formed regularly and in accordance with the rotation of the central shaft and immediately conveyed into the first turn on the storage drum during the operation of the thread delivery device, and retransmission of one or more twists against the direction of the thread from the point of origin at the transition from the central shaft to the Preventing winding element is maintained, the desired balance between the generated and the resolved twists is maintained. Thanks to the twisting support of the running thread in the rotating central shaft, a twist is reliably formed in each turn on the storage drum, which is released again when this turn is pulled off. As a result, the thread runs completely twist-free into the textile machine, provided that the thread has already been fed to the thread delivery device without twist.

In the thread delivery device, the incoming thread is supported and guided in a stationary manner against twisting, at least during the transition from the central shaft to the winding element, using the strip cross-section, so that the thread can only be rotated after it has emerged from the strip guide gap. The gap has a check valve function due to its shape and due to its position during the transition, and prevents a nascent twist from planting back against the direction of the thread or that several twists can jam. On the other hand, the stationary thread guide gap means that each twist is immediately conveyed through the winding element into the winding on the storage drum when the central shaft is rotated. In the thread winding on the storage drum, each turn contains only one Twist. This twist is released when a turn is pulled off overhead of the storage drum. It is important that the thread is not only supported against twisting in the tape guide gap when the thread delivery device is running, but also when the thread delivery device is at a standstill, because then a twist could have a tendency to move in the direction of lower resistance, i.e. in the opposite direction of the thread running expand the central shaft and jam at the transition the next time you start.

Furthermore, according to the method, the thread is to be supported in a form-fitting manner with each revolution of the central shaft in order to control the formation and the transport of each twist. This prevents a twist from sticking to the obstacle of the transition while the thread is running.

In the thread delivery device, the band guide gap is designed as a slot nozzle penetrating the central shaft, the gap width of the width and the gap width also exceeding the thickness of the band-like thread, preferably only slightly in each case, in order to ensure reliable twist protection of the thread.

The tape guide gap is structurally simple at the free end of a carrier insert penetrating into the central shaft from the inlet side or even formed from its free end. The carrier insert is supported in a stationary manner outside the central shaft on a housing wall of the thread delivery device, such that forces resulting from the guidance of the thread and the deflection into the winding element are transmitted to the outside via the carrier insert and are absorbed on the housing wall. The carrier insert should not contact the rotating central shaft.

A tube as a carrier insert is sufficiently rigid and ensures that the thread cannot get caught or tangled in its path up to the tape guide gap. A pinched pipe end can form the tape guide gap.

Alternatively, the slot nozzle forming the tape guide gap is interchangeably attached to the carrier insert. Depending on the type of thread, ie its bandwidth and Band thickness and its structure (smooth, rough, or fibrous), a suitable slot nozzle is used.

Alternatively, the slot nozzle can be exchanged together with the carrier insert if it is necessary to switch from a thread quality to a significantly different thread quality.

The axial penetration depth of the tape guide gap into the central shaft is particularly expedient in order to be able to position the tape guide gap in an optimal axial position relative to the transition into the winding element.

In order to minimize the resistance to movement of the thread in the tape guide gap, and also to prevent wear and tear, the tape guide gap should be made of slippery and wear-resistant material.

The tape guide gap expediently has a guide section with at least approximately the same cross section. It is expedient to form the tape guide gap with a slightly widened outlet mouth.

In order to ensure that a twist is formed with each revolution of the central shaft, at least one twist recess, which acts on the thread in a form-fitting manner and rotates with the central shaft, is provided in the transition. The twist depression not only softens the deflection of the thread, but also assists in the positive rotation of the central shaft to form the twist.

It is advantageous to arrange the twist recess in the hollow of the knee between the hollow inner channel of the central shaft and a tube channel of the winding element. The thread emerging from the stationary tape guide gap and deflected into the tube channel of the winding element is gripped by the recess and carried along in the direction of rotation.

In order to ensure a defined thread control, a closed inner eyelet or an inner part eyelet can be provided in the transition, in which the twist recess is shaped. The inner part eyelet can only extend approximately over the width of the twist recess.

A V-shaped incision as a twist recess is technically simple, the incision base roughly halving the kink angle between the central shaft and the winding element. This ensures a gentle deflection of the thread and a weakening of the obstacle at the transition.

In terms of assembly technology, the carrier insert is mounted on the housing wall with the aid of a fastening part. The fastening part can be in the form of a cap in order to ensure stable support. This cap can define a receiving space for a sensor which is used for other tasks in this area of the thread feeder.

An embodiment of the subject matter of the invention is explained with the aid of the drawing. Show it:

Fig. 1 shows a longitudinal section through a yarn delivery device, and

Fig. 2 is an enlarged, in Fig. 1 highlighted by a circle section of the yarn feeder.

A thread delivery device F in FIG. 1 contains in a housing 1 a drive motor M for a central shaft S which is hollow in its section 4 leading to a housing wall 2. The central shaft S supports a coaxial storage drum D in a conventional manner that is not highlighted in more detail. The storage drum D is rotatable on the central shaft S and is held against rotation by magnets 3 (stationary storage drum). A winding element W extends obliquely outwards from the central shaft S, which has an internal tube channel 6 'and a winding tube 6 which extends it and is incorporated into a winding disc 5 which rotates between the housing 1 and the storage drum D. A thread eyelet C is fitted in an outlet 12 of the winding element W. There is a transition 7 between the winding element W and the cavity 8 of the central shaft S. The cavity 4 of the central shaft S and the winding element W define a thread travel path for a thread Y, which is deflected coming from the left at the transition 7 in FIG. 1, passes through the winding element W, is deflected at the thread eyelet C and on the outer circumference of the storage drum D is wound in successive and adjacent turns in a thread winding H forming an intermediate supply. The thread Y is drawn overhead from the thread reel H of the storage drum D, that is to say with a circumferential thread draw-off point over its circumferential draw-off edge 11 through a thread brake B, to a draw-off eyelet E2 coaxial with the storage drum D and through this further to a textile machine, not shown, for example one Loom, delivered. The thread Y originally comes from a thread supply, not shown, for example a thread spool.

Due to the rotary movement of the central shaft S with the winding element W, the thread Y is drawn into the thread delivery device F at a thread speed corresponding to the rotational speed. The thread winding H is held on the storage drum D with a size set by sensors that are not shown in detail. The textile machine consumes the thread Y intermittently in the case of a weaving machine, the motor M being driven faster or slower to maintain the thread winder H with the predetermined size. If there is no consumption, the engine M is stopped.

When the central shaft S is rotating, a 360 ° twist is formed at each transition in the course of the deflection of the thread Y at the transition 7, which twist is transported into the first turn in the thread winding H with the running thread. A 360 ° twist T is indicated in the last turn of the thread winding H just shown during the pull-off. When thread Y is taken off overhead, the thread take-off point at the take-off edge 11 revolves in the direction of rotation of the central shaft S, and is dissolved again in the thread with each full, drawn-off turn of the 360 ° twist

The design and function of the thread delivery device F described so far is conventional. The thread delivery device shown according to the invention is intended for processing threads Y with a ribbon-like character. Such threads can be, for example, polypropylene monofilaments, so-called Lurex threads, tapes or foil tapes, the common characteristic of which is at least approximately a rectangular cross-section with a tape width exceeding the tape thickness. However, the cross section does not necessarily have to correspond to a rectangle, but could also be oval, biconcave or biconvex. Such threads often have to be processed without twist, because twists introduced into the end product produce visible and tactile fabric defects or lead to thread breaks or other faults or, in the case of particularly strong threads with a band-like character, for example carbon threads, when passing through scanning or braking devices along the Thread travel can result in malfunctions.

In order to process the thread Y without twist, measures are taken upstream of the thread delivery device F in order to insert the thread from the thread supply into the thread delivery device F without twist. For example, in the event of axial withdrawal from a thread bobbin, the thread bobbin is rotated in accordance with the thread speed in the thread delivery device in such a way that the point of withdrawal of the thread from the thread bobbin remains in space. Another possibility is to unwind the thread tangentially from a cylindrical thread spool and to rotate the thread spool in the take-off direction at the thread speed in the thread delivery device.

Depending on the function, and as explained above, in the thread delivery device F, this type of construction forms a 360 ° twist at the transition 7 at every full revolution, which is eliminated again when the head is drawn off. In this respect, the thread delivery device F should theoretically have no influence on the twist-free processing of thread already fed without twist. In practice, however, it turns out that not every turn in the thread winding H contains a 360 ° twist T, but that a twist is jammed at the transition 7 or even several twists are jammed there, so that some turns on the storage drum D do not have a twist contain or in the case of sudden conveyance of several pent-up twists, some thread turns contain several twists. This imbalance then leads to either an overhead deduction Counter-twisted is formed and introduced into the textile machine or only one of the several twists is dissolved in one turn and the remaining ones run into the textile machine.

In order to avoid this disturbance of the balance, according to the invention the thread delivery device F is provided with additional equipment. Directly at the transition 7 from the cavity 4 of the central shaft S into the winding element W, a tape guide gap G is positioned stationary, which (FIG. 2) is shaped like a slot nozzle, the gap width of which is slightly larger than the tape thickness and the gap width is greater than the bandwidth of thread Y with a band-like character. The band guide gap G is arranged on a carrier insert A, for example a tube 8. The carrier insert A is inserted into the hollow section 4 of the central shaft S from the inlet end and is positioned by a holding element 9 which can be attached, for example, to the housing wall 2. The holding element 9 contains a thread eyelet E1 on the inlet side and defines here a cavity 10 in which, for example, a sensor can be accommodated.

According to FIG. 2, the band guide gap G, which is designed as a slot nozzle, is formed with a guide section 15 which extends in the thread running direction or parallel to the axis of the central shaft S and an outlet opening 16 which is, for example, widened in a rounded manner. The front end of the carrier insert A, which is designed as a tube 8, is shaped conically tapering or squeezed together (at 14). The tape guide gap G is thus formed by the free end of the tube 8. Alternatively, the carrier insert A could also be a rod or double rod, which positions an interchangeably attached slot nozzle. The depth of penetration of the tape guide gap E into the central shaft S can be adjustable. It is also conceivable to extend the tape guide gap G over a larger part or the entire depth of penetration.

In addition, a twist recess N, for example in the form of a V-cut, is formed in the transition 7, the cut base 13 of which is roughly halved the deflection angle between the axis of the central shaft S and the winding element W. The twist recess N is provided on the inner hollow of the knee of the transition 7. The tape guide gap G is positioned, for example in the axis of the central shaft S, that the emerging thread reliably runs into the twist recess N and is carried along by it.

The stationary positioned tape guide gap G acts like a check valve, which not only prevents a twist from jamming in front of the transition 7, but also ensures that twists deform back into the hollow section 4 of the central shaft S against the direction of the thread. Rather, each twist is reliably carried along with the running thread during its formation and brought into the first turn on the storage drum D, so that ultimately every turn in the thread winding H contains a 360 ° twist T, which is reliably dissolved again when the head is drawn off. The twist recess N acts in a form-fitting manner by ensuring the correct shaping and the immediate removal of the nascent twist and by mitigating the mechanical effect of the obstacle of the transition 7 for the transport of the twist. However, the twist recess N is not absolutely necessary.

In other words, the thread Y is supported and guided against twisting immediately before the transition 7, the guiding suppresses the reshaping of twists against the direction of travel, and so any twist being created is immediately transported further through the winding element W. The twist recess N supports the correct shaping of each twist and the unimpeded further transport of the nascent twist. The thread introduced into the thread delivery device F without twist leaves the thread delivery device reliably without twist.

The tape guide gap G is expediently formed from sliding-resistant and wear-resistant material or at least covered with such material. A so-called central eyelet made of slippery and wear-resistant material can be positioned in the transition 7, which is closed in the circumferential direction or at least extends over the circumferential area of the twist recess N.

The carrier insert A with the tape guide gap G can be removed when not in use. It can also be a retrofit part with which conventional thread delivery devices can subsequently be converted into twist-free thread delivery devices. The storage drum D, which is only indicated schematically, can be a rod cage with rods which can be moved relative to one another in order to produce a thread separation (axial spacing between the turns in the thread winding H).

Claims

claims

1. Method for the twist-free delivery of a thread (Y) with a band-like character in a textile machine, in particular in a weaving machine, in which the thread is removed from a supply without twist and into a thread delivery device (F) by means of its rotatable central shaft (S) and one of them external winding element (W) wound up on a stationary storage drum (D) and delivered from the storage drum overhead to the textile machine, characterized in that the thread (Y) is supported in the central shaft (S) against twisting, and function-related twists ( T) are prevented from reshaping into the central shaft in order to form a 360 ° twist (T) in each turn on the storage drum (D).

2. The method according to claim 1, characterized in that the thread is acted upon twice during the forming of the twist (T) and the transport onto the storage drum in a form-fitting manner.

3. Thread delivery device (F) for the twist-free delivery of a thread (Y) with a band-like character into a textile machine, in particular into a weaving machine, with a stationary storage drum (D) for a thread winding (H) consisting of several adjacent turns and with a rotatable, hollow Central shaft (S) with the winding element (W) projecting outwards therefrom, the thread path running axially through the central shaft (S) and the winding element up to the storage drum (D) and continuing axially via an overhead pull-off end of the storage drum (D) characterized in that along the thread path in the central shaft (S) in the region of the transition (7) from the central shaft into the winding element there is at least one tape guide gap (G) which is stationary relative to the central shaft (S).

4. Thread delivery device according to claim 3, characterized in that the band guide gap (G) is formed as a slot nozzle penetrating into the central shaft (S) with the band width, preferably only slightly exceeding the gap width and the band thickness, preferably only slightly exceeding gap width.

5. Thread delivery device according to claim 3, characterized in that the tape guide gap (G) at the free end of a from the inlet side in the central shaft (S) engaging carrier insert (A) is arranged or formed by the outside of a housing wall (2) of the Thread delivery device (F) is supported stationary.

6. Thread delivery device according to claim 5, characterized in that the carrier insert (A) is a tube (8) with a conically tapering or flat-crimped tube end (14).

7. Thread delivery device according to claim 4 or 5, characterized in that the slot nozzle on the carrier insert (A) is interchangeably attached to another slot nozzle with different dimensions.

8. Thread delivery device according to claim 5, characterized in that the carrier insert (A) is interchangeably attached.

9. Thread delivery device according to claim 4, characterized in that the axial depth of penetration of the tape guide gap (G) in the central shaft (S) is adjustable.

10. Thread delivery device according to claim 3, characterized in that the tape guide gap (G) consists at least partially of slippery and wear-resistant material.

11. Thread delivery device according to claim 3, characterized in that the tape guide gap (G) has a guide section (15) oriented in the thread running direction with at least approximately the same cross section, and preferably, a widened outlet mouth (16).

12. Thread delivery device according to claim 3, characterized in that in the transition (7) at least one on the thread (Y) positively acting twist recess (N) is provided.

13. Thread delivery device according to claim 12, characterized in that the twist recess (N) is arranged in a hollow of the knee between the hollow inner channel (4) of the central shaft (S) and a tube channel (6, 6 ') of the winding element (W).

14. Thread delivery device according to claim 12, characterized in that an inner eyelet or an inner eyelet is provided in the transition (7), in which the twist recess (N) is formed.

15. Thread delivery device according to claim 12, characterized in that the twist recess (N) is an approximately V-shaped incision, the incision base (13) approximately halves the kink angle between the central shaft (S) and the winding element (W).

16. Thread delivery device according to claim 5, characterized in that the carrier insert (A) on a housing wall (2) of the thread supplier ts (F) attachable fastening part (9), preferably a cap, is fixed.