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Patent Searching and Data


Title:
WEAVING LOOM
Document Type and Number:
WIPO Patent Application WO/1985/005384
Kind Code:
A1
Abstract:
Apparatus for turning a weft yarn (16) into a warp shed for creation of a selvedge, the apparatus including a movable guide (12) which in a first position is located outside the warp sheet to receive a weft yarn (16) end after weft insertion, and which is movable to a second position located within the warp shed whereat the guide (12) serves to separate the weft yarn end from the warp threads (18) and a nozzle (14) associated with the guide (12), the nozzle (14) directing a flow of fluid along the guide (12) for carrying the weft yarn end into the warp shed.

Inventors:
GRIFFITH JOHN DALTON (GB)
Application Number:
PCT/GB1985/000208
Publication Date:
December 05, 1985
Filing Date:
May 17, 1985
Export Citation:
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Assignee:
SULZER AG (CH)
International Classes:
D03D47/48; (IPC1-7): D03D47/48
Domestic Patent References:
WO1983002466A11983-07-21
Foreign References:
US3153430A1964-10-20
DE2707682B11978-02-02
FR2141808A11973-01-26
DE605360C1934-11-09
GB543398A1942-02-24
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Claims:
CLAIMS
1. Apparatus for turning a weft yarn into a warp shed for creation of a selvedge, the apparatus including a movable guide which in a first position is located out¬ side the warp sheet to receive a weft yarn end after weft insertion, and which is movable to a second position lo¬ cated within the warp shed whereat the guide serves to separate the weft yarn end from the warp threads and a nozzle associated with the guide, the nozzle directing a flow of fluid along the guide for carrying the weft yarn end into the warp shed.
2. Apparatus according to Claim 1 wherein the movable guide includes a pair of arms spaced apart to define a gap for receiving the weft yarn end and for guiding flow of fluid t erealong for carrying the weft yarn end into the warp shed.
3. Apparatus according to Claim 1 or 2 wherein the mov¬ able guide is arranged so that in its first position it is aligned with the path of weft insertion so as to re¬ ceive the weft yarn end.
4. Apparatus according to Claim 1 or 2 wherein the guide is located downstream of the path of weft insertion so as to receive the protruding weft yarn end during the beatup cycle.
5. Apparatus according to Claim 4 wherein a weft yarn holding device is located upstream of the guide for re¬ ceiving the weft yarn prior to beatup.
6. A method of turning a weft yarn end into a warp shed for creation of a selvedge, the method including receiv¬ ing the weft yarn end protruding from the warp sheet in a movable guide, after beatup moving the guide into the newly formed shed to provide a passageway for the weft yarn end, directing a flow of fluid along the passageway to move the weft yarn end into the shed, removing the guide from the shed whilst maintaining said flow of fluid for maintaining the weft yarn end in position until beat up of the subsequently inserted weft yarn.
Description:
WEAVING LOOM The present invention relates to apparatus for use in a weaving loom for turning weft thread ends into the shed to create a selvedge, and to a weaving loom includ¬ ing the apparatus. 5 In particular, the present invention is suitable for use with a fluid jet loom for creating a selvedge at the side of the warp sheet opposite to that at which weft insertion takes place.

Turning-in of weft thread ends is known as a tech- 10 nique for creating a selvedge and is achieved by either using a needle which engages the weft thread end and positions it within the shed prior to beat up or using several jet nozzles as demonstrated in U.K. Patent 543,398 for blowing the weft thread end into the shed 15 prior to beat up. Both of these modes of operation have drawbacks and are unsuitable particularly at high pick rates.

For instance, the first mode of operation requires precision in construction and setting up in order to en- 20 sure that the needle correctly engages with the weft thread end. Additionally, since the needle penetrates into the shed it must be removed before beat-up can be completed. Accordingly immediately before beat-up the weft thread end is unsupported and so is able to relax 25 thereby creating a loose selvedge which is unsatisfact¬ ory.

With regard to the second mode of operation the weft thread end is inserted by streams of air flowing from jet nozzles and has the tendency to snag against the warp 30 threads. This tendency obviously increases if the weft thread and/or warp threads are of a hairy character. Accordingly correct turning-in is not consistently assur¬ ed and so can result in an irregular selvedge. Addition¬ ally use of several jet nozzles necessitates a high con- 35

sumption of pressurised air.

It is a general aim of the present invention to pro¬ vide an apparatus for turning-in weft thread ends which overcomes or substantially eliminates the drawbacks re¬ ferred to above.

According to one aspect of the present invention there is provided apparatus for turning a weft yarn into a warp shed for creation of a selvedge, the apparatus including a movable guide which in a first position is located outside the warp sheet to receive a weft yarn end after weft insertion, and which is movable to a second position located within the warp shed whereat the guide serves to separate the weft yarn end from the warp threads and a nozzle associated with the guide, the nozzle directing a flow of fluid along the guide for carrying the weft yarn end into the warp shed.

Preferably the movable guide includes a pair of arms spaced apart to define a gap for receiving the weft yarn end and for guiding flow of fluid therealong for carrying the weft yarn end into the warp shed.

According to another aspect of the present invention there is provided a method of turning a weft yarn end into a warp shed for creation of a selvedge, the method including receiving the weft yarn end protruding from the warp sheet in movable guide, after beat-up moving the guide into the newly formed shed to provide a passageway for the weft yarn end, directing a flow of fluid along the passageway to move the weft yarn end into the shed, removing the guide from the shed whilst maintaining said flow of fluid for maintaining the weft yarn end in posi¬ tion until beat-up of the subsequently inserted weft yarn.

Various aspects of the present invention are herein¬ after described with reference to the accompanying draw- ings, in which:-

Figure 1 is a schematic illustration of an apparatus according to the present invention shown in situ on a loom which has just completed. beat-up;

Figures 2 and 3 are views similar to Figure 1 show- ing progressive stages of the turning-in process of the weft yarn end; and

Figure 4 is a schematic end view of the apparatus shown in Figure 1.

An apparatus according to the present invention is generally shown at 10 and includes a guide member 12 and associated fluid jet nozzle 14, the fluid usually being compressed air. The jet nozzle 14 is aligned substant¬ ially in line with the fell position and is positioned to one side of the warp sheet 18 for directing a stream of air into the shed in a direction opposite to the direc¬ tion of weft insertion.

The guide member 12 is generally positioned between the jet nozzle 14 and the adjacent side of the warp sheet. The guide member 14 includes a pair of arms 20, 21 which are mounted on a rotary shaft 23 so as to be spaced apart to define a gap 24 therebetween. The arms 20, 21 are conveniently formed from a thin gauge strip of metal or similar material.

The guide member 12 is movable between first and second positions. In the first position it is located so that it is able to receive the weft yarn end within the gap after the weft yarn has been fed across the warp shed. This may be achieved by positioning the guide mem¬ ber 14 so that in its first position it is aligned with the path of weft insertion so that weft yarn passes through the gap as the weft yarn passes beyond the warp sheet at termination of the weft insertion cycle or al¬ ternatively, as per the illustrated embodiment, the guide member 14 may be positioned adjacent a weft yarn holding device 26, as for instance described in our European Pat-

ent Application 83900427. In such an arrangement the guide is positioned downstream of the path of weft inser¬ tion so that the protruding weft yarn end is moved into the gap 24 during beat-up as illustrated in Figure 1. Reference should be made to our European Application No. 83900427 for an understanding of the operation of the holding device. After beat-up, the reed 28 is retract¬ ed and shaft 23 is rotated to move the guide member 12 to its second position whereat it is located within the new- iy created shed as close as possible to the fell of the shed. This position is illustrated in Figure 2. In this position the spaced apart arms 20, 21 effectively define a passageway extending longitudinally of the fell and along which passageway the weft yarn end may be moved without contacting the warp threads.

The jet nozzle 14 is positioned so as to direct its emitted flow into the gap 24 i.e. along the passageway so that its emitted air—-.flow is guided between the arms. This concentrates and regulates the air flow through the gap 24.

On actuation, the air flow from the jet nozzle 14 carries the weft yarn end between the arms 20, 21 and into the warp shed. The weft yarn end during its passage into the warp shed is separated from the warp threads by the arms 20, 21, and so is restrained from snagging on them.

After the weft yarn end has been inserted into the warp shed, the arms 20, 21 are retracted back to their initial position to receive the next weft yarn end whilst the jet nozzle 14 continues to emit a flow of air into the warp shed, preferably until after beat-up.

In this way the weft yarn end is maintained in posi¬ tion within the warp shed up to and during beat-up and so is correctly positioned and maintained under tension whilst beat-up occurs.