GB2314095A

GB2314095A - Gripper Axminster type loom

Info

Publication number: GB2314095A
Application number: GB9612497A
Authority: GB
Inventors: John Dalton Griffith
Original assignee: Griffith Textile Machines Ltd
Current assignee: Griffith Textile Machines Ltd
Priority date: 1996-06-14
Filing date: 1996-06-14
Publication date: 1997-12-17
Anticipated expiration: 2016-06-14
Also published as: GB2314095B; GB9612497D0

Abstract

A loom of the gripper Axminster type uses a rapier or pair of rapiers 51 to insert the weft. Fingers 20 or the beat-up reed define a guide channel 26 for the rapier(s).

Description

GRIPPER TYPE LOOM The present invention relates to gripper type looms, particularly of the type for weaving Axminster type carpets.

A typical example of a carpet loom of the gripper Axminster type is disclosed in UK Patent No. 1075082. Such looms are provided with grippers which transfer a tuft of yarn from a yarn supply to the fell of the shed for trapping into the weave.

In a typical gripper loom the weft is inserted by a single rigid needle. This can be a limiting factor for operation of the loom, eg. for a loom weaving say 4 yards width a pick rate of 55 picks per minute is typical.

It is well known in other types of weaving for weft to be inserted by two opposed rigid or flexible rapiers with yarn holding heads to pick up the weft and pull it to the centre of the shed with one rapier and transfer it and pull it across the shed with the other rapier. In order to ensure transfer of the weft from one rapier to the other, the rapier heads have to be accurately positioned in the centre of the shed. On other looms this is normally done with guides formed from a series of spaced fingers, each of which is normally at least 2 mm thick. This type of guide is unsuitable for a gripper loom as it would interfere with the grippers of an Axminster loom.

It is a general aim of the present invention to provide a gripper type'.

loom, particularly for Axminster carpet weaving, which preferablyç incorporates two opposed rapiers for inserting the weft yarn:.

Incorporation of two opposed rapiers in a gripper loom is desirable as it enables higher pick rates to be achieved.

It is also an aim of the present invention to provide a gripper loom within a rapier guide which is defined by the reed fingers of the beat-up reed. In this way the weft insertion may be achieved using a single flexible rapier or a pair of opposed rapiers.

According to one aspect of the present invention there is provided a gripper type loom including a pair of opposed rapiers for inserting weft yarn.

Preferably the present invention provides a gripper type loom including a plurality of grippers for transferring tufts of yarn to the fell of the fabric being woven, a single rapier or a pair of opposed rapiers for inserting weft yarn, and a beat-up reed comprising a plurality of reed fingers of plate-like form, the: beat-up reed defining a guide for said single rapier or said pair of opposed rapiers.

Preferably the reed fingers have a thickness in the range of 0.4 to 0.7 mm. Preferably the reed fingers are spaced apart to define dents having a width in the range of 3 to 4 mm. Preferably a gripper is provided for each dent.

Preferably the guide in the beat-up reed is defined by an open topped channel, the channel having a lower portion of which defines a lower guide support surface for maintaining the rapiers spaced from the lower shedded warp sheet, the channel further including opposed side walls for restricting sideways deflection (in the warp direction) of the rapiers.

In one embodiment, the open topped channel is defined by a restricted mouth opening having a width less than the width of each rapier so as to define an upper guide support surface for maintaining the rapiers spaced from the upper shedded warp sheet.

In another embodiment, the open topped channel is defined by a non-restricted mouth opening having a width greater than the width of each rapier, each rapier preferably being provided with a head portion capable of engaging the upper shedded warp sheet.

Various aspects according to the present invention are hereinafter described with reference to the accompanying drawings, in which: Figure 1 is a schematic side view of a beat-up reed according to a first embodiment of the present invention; Figure 2 is a schematic side view of a beat-up reed according to a second embodiment of the present invention; Figure 3 is a schematic side view of a beat-up reed according to a third embodiment of the present invention; Figure 4 is a schematic side view of a beat-up reed according to a fourth embodiment of the present invention.

Reference is initially made to Figure 1.

The reed 10 includes a plurality of individual reed fingers 20 (only one being shown) mounted on a sley (not shown). The fingers 20 are spaced apart in the weft direction so as to define a dent between adjacent fingers 20. In the illustrated embodiment the dent has a width of about 3 mm.

In the illustrated embodiment a multiplicity of warp yarns 12, 14 are fed through each dent. In addition, a gripper 18 is provided for each dent. In the illustrated embodiment the gripper 18 is located within a dent and is holding a tuft of yarn at the fell in readiness for beat-up. The reed 10 is movable between a weft insertion position (shown in solid lines) and a beat-up position (shown in broken lines).

Each finger 20 is generally of flat plate-like form and includes a guide portion 22 and a beat-up portion 21. Advantageously each finger is stamped from a suitable metal sheet of steel and has a thickness of about 0.5 mm.

The guide portion 22 includes a channel opening 23 which is located in the shed opening 30 when the reed 10 is in its weft insertion position. The openings 23 of adjacent fingers 20 are aligned and cooperate to define a rapier guide channel which extends in the weft direction along the reed 10, the channel having an open top defined by a channel mouth 24.

Each opening 23 includes a lower guide support surface 26 which is defined by a pair of shoulders 27 spaced apart by a central recess 28.

If desired recess 28 may be omitted such that the lower guide surface 26 is defined by a single continuous shoulder. Central means 28 is advantageously provided as it provides a recess into which the lower shedded yarn 14 may pass as it crosses the reed finger and thereby isolates it from the rapier during weft insertion.

As seen in Figure 1, when the reed 10 is located at its weft insertion position, the support surface 26 is located above the lower shedded warp sheet defined by yarns 14 and so the rapier 50 travelling along the channel is spaced from the lower warp sheet.

As seen in Figure 1, the rapier 50 preferably includes an elongate body 51 upon which a rapier head 52 is mounted. The channel mouth 24 is of a width greater than the rapier head 52 to thereby enable the rapier to pass along the channel whilst the rapier body 51 is positively guided within the channel.

The opening 23 has opposed side walls 30, 31 which co-operate with opposed sides 32, 33 of the rapier body 51 in order to restrict sideways movement, in the warp direction, of the rapier 50 during weft direction.

In Figure 1, the opening 23 includes a channel mouth 24 of restricted width, ie. a width less than the width of the rapier body 51. In this respect, the opening 23 includes an upper guide support surface 36 which overlies a marginal portion of the rapier body 51 and acts to restrict upward deflection of the rapier body 51 during weft insertion. As seen in Figure 1, the upper surface 36 is spaced from the upper shedded warp sheet defined by warp yarns 12 such that the rapier head 52 is spaced from the upper warp sheet during weft insertion.

In Figure 1 the upper guide support surface 36 is defined by a single shoulder 38.

The embodiment shown in Figure 2 is the same as that illustrated in Figure 1 except that the rapier head 52 is located centrally of the rapier body 51 and except that the upper support surface 36 is defined by a pair of opposed shoulders 38, 39 which co-operate with respective marginal portions of the rapier body 51.

The embodiment shown in Figure 3 is the same as that illustrated in Figures 1 and 2 except that the channel mouth 24 is of a width greater than the width of the rapier body and except that the opening 23 is not provided with an upper guide support surface 36. Instead, the rapier head 52 is provided with an upper guide surface 53 which is intended to engage the upper shed sheet defined by yarns 12 in order to restrict upward deflection of the rapier 50 during weft insertion.

In the embodiments of Figures 1 to 3, the rapier body 51 is of flat strip-like form and is preferably fonned so as to be flexible in the upwards/downwards direction.

The embodiment illustrated in Figure 4 is similar to that illustrated in Figure 3 except that the rapier body 51 is formed so as to be relatively rigid and is preferably of generally circular cross-section. In Figure 4, the rapier head has not been illustrated.

The beat-up portion 21 includes a leading edge 40 for engaging the weft yarn at beat-up. The portion 21 also includes a window 42 through which warp yarns 12, 14 are threaded. This ensures that the warp yarns 12, 14 are held captive in a given dent at all times.

Claims

1. A gripper type loom including a plurality of grippers for transferring tufts of yarn to the fell of the fabric being woven, a single rapier or a pair of opposed rapiers for inserting weft yarn, and a beat-up reed comprising a plurality of reed fingers of plate-like form, the beat-up reed defining a guide for said single rapier or said pair of opposed rapiers.

2. A loom according to claim 1 wherein the reed fingers have a thickness in the range of 0.4 to 0.7 mm.

3. A loom according to claim 2 wherein the reed fingers are spaced apart to define dents having a width in the range of 3 to 4 mm.

4. A loom according to claim 3 wherein a gripper is provided for each dent.

5. A loom according to any of claims 1 to 4 wherein the guide in the beat-up reed is defined by an open topped channel, the channel having a lower portion of which defines a lower guide support surface for maintaining the rapiers spaced from the lower shedded warp sheet, the channel further including opposed side walls for restricting sideways deflection (in the warp direction) of the rapiers.

6. A loom according to claim 5 wherein the open topped channel is defined by a restricted mouth opening having a width less than the width of each rapier so as to define an upper guide support surface for maintaining the rapiers spaced from the upper shedded warp sheet.

7. A loom according to claim 5 wherein the open topped channel is defined by a non-restricted mouth opening having a width greater than the width of each rapier, each rapier preferably being provided with a head portion capable of engaging the upper shedded warp sheet.

8. A loom according to any of claims 5 to 7 wherein the lower portion of the channel includes a recess into which a lower shedded yarn may pass as it crosses the reed finger.

9. A gripper-type loom including a pair of opposed rapiers for inserting weft yarn.

10. A gripper type loom substantially as described with reference to and as illustrated in the accompanying drawings.