GB2174417A - Needle loom - Google Patents

Abstract

A rapier or needle weaving loom having a catch needle 20 located on the side of the woven fabric opposite to the side at which weft yarn is inserted, the catch needle being mounted for axial reciprocation between an extended position and a retracted position, the catch needle being arranged to move to its extended position to project through the weft loop 21a, 21b created by the weft rapier 16, and a movable deflection means 50 for engaging the weft loop portion closest to the fell and moving said loop portion toward the fell prior to retraction of the rapier. <IMAGE>

Description

SPECIFICATION Needle loom The present invention relates to a needle weaving loom, for instance, as used for weaving narrow fabrics.

In our co-pending United Kingdom Patent Application 8121842 (publication No: 2101641A) we have described a weaving loom having a catch needle which in order to knit the catch thread merely reciprocates axially without rotation and which has an end formation capable of knitting without the use of a latch or other ancillary devices. The present invention is concerned with a similar weaving loom and catch needle.

Various aspects of the present invention are hereinafter described with reference to the accompanying drawings, in which: Figure 1 is a part perspective view of a weaving loom showing schematically the catch needle and rapier needle; Figure 2 is a plan view of the loom as shown in Fig. 1; Figure 3 is a side view of the loom as shown in Fig. 1; In Fig. 1 there is shown a portion of woven fabric 10 and several warp threads 12 which have been parted to create a shed. A needle or rapier 14 which inserts the weft thread 16 is shown projecting through the shed as it reaches the termination of its insertion stroke and is about to return.

The rapier 16 in the position shown in Fig.

1 has created a loop in the weft thread and as is conventional practice, the catch needle 20 has penetrated between the loop portions 2lea, 21b of the weft thread to pick up the catch thread 30.

The catch needle 20 has a shank portion 40 and a terminal end formation 41 which includes a hook portion 42 and a channel or throat 43. The terminal end 44 of the hook is positioned below the surface 45 of the needle shank 40 so that yarn lying perpendicularly across the needle may be slid along the needle and over the terminal formation 41 without being caught by the hook portion. However, if yarn is laid obliquely across the needle shank so as to be capable of entering throat 43 then on moving the yarn along the needle towards the end formation 41 the yarn will eventually enter the throat 43 and be caught by the hook portion 42.

As seen in the Figures, the needle is arranged so that the hook portion 42 faces downwards towards the weft thread loop portion 21 a and the catch thread 30.

The catch thread 30 is guided by a thread guide eye 31 which is located on a reciprocating lever 33. The lever 33 is reciprocated by a cam arrangement (not shown) to raise and lower the guide eye 31 in synchronism with rapier 16 and catch needle 20. In its uppermost position the guide eye 31 is arranged to be located above the end formation 41 so that the catch thread extends upwardly from the edge of the fabric past the extended catch needle 20 to the guide eye 31. The path of axial reciprocation of the catch needle 20 is preferably chosen so that the catch thread is deflected slightly downwardly by the catch needle so that the catch thread resiliently bears against the under surface of the catch needle. Accordingly, on retraction of the catch needle entry of the catch thread into throat 43 is encouraged due to the thread being resiliently biased upwardly.

In order to reduce the amount of axial displacement of the catch needle during knitting the lever 33 is provided with a deflection arm 50, the arm 50 being conveniently formed from a resilient wire.

The arm 50 is positioned on the lever 33 and arranged so that as the lever 33 moves upwardly to move the guide eye 31 to its upper position, the arm 50 engages the weft thread loop portion 21a and deflects it toward the fell 11 of the shed. Accordingly the catch needle is able to pick up the catch thread at a position closer to the fell 11 of the shed due to the greater separation between the loop portions 21a and 21b, and also due to the loop portion 21 a being positioned closer to the fell 11 of the shed.

Since the axial displacement of the catch needle is reduced it enables higher weaving speeds to be attained.

As seen in the drawings, the catch needle 20 of preferably provided with a recess 60 on its under surface.

The recess 60 is located on the catch needle 20 so that when the needle 20 is in its extended position the weft thread loop portion 21a is positioned within the recess 60. This is advantageous as it enables the catch thread to extend upwardly past the catch needle without being deflected downwardly by the weft thread. Thus whilst the weft thread is positioned in the recess 60 it does not interfere with the passage of the catch thread across the catch needle. Accordingly, the catch needle is able to operate reliably at high speeds without missing pick up of the catch thread even though the terminal end formation 41 picks up the catch thread in close proximity to the weft thread loop portion 21 a.

Advantageously the rapier 14 has a hook formation 70, preferably in the form of a shoulder 71, which serves to collect the catch thread 30 on its return stroke and causes the catch thread 30 to wrap further around the needle 20. On further retraction of the rapier 14 the catch thread rides out of contact with the shoulder 71 and is thereby automatically released from the rapier. It has been found that the provision of the hook formation 70 further ensures reliability in the catch needle 20 picking up the catch thread 30 during high operating speeds.

Claims (1)

1. A rapier or needle weaving loom having a catch needle located on the side of the woven fabric opposite to the side at which weft yarn is inserted, the catch needle being mounted for axial reciprocation between an extended position and a retracted position, the catch needle being arranged to move to its extended position to project through the weft loop created by the weft rapier, and a movable deflection means for engaging the weft loop portion closest to the fell and moving said loop portion toward the fell prior to retraction of the rapier.