GB2113259A - Rapier loom - Google Patents

Abstract

In order to maximise utilisation of a rapier loom such loom is provided with a rapier mechanism (37) at one side thereof which is adjustably operable throughout the full loom width or throughout a part only thereof, that a double selvedge mechanism (38) be removably positioned intermediate the sides of the loom for operation with the aforesaid rapier mechanism, and that a further rapier mechanism (37) be provided at the opposite side of the loom for cooperation with the double selvedge mechanism (38). The double selvedge mechanism (38) may, when weaving a single fabric, be sitable adjacent that side of the loom opposite to the first mentioned rapier mechanism for cooperation therewith, or a separate selvedge mechanism may be provided. <IMAGE>

Description

SPECIFICATION Rapier looms The invention concerns weaving looms, and has more particular reference to rapier looms of the kind wherein the weft yarns are introduced into the warp shed as a double pick.

Difficulty is experienced in providing a secure selvedge at each edge of a fabric produced on a rapier loom by the insertion of a succession of double picks of weft yarn, in that the end of the loop defining the double pick remote from the yarn supply requires to be held during shed change and thus gives rise to a fringe at that edge in the eventual fabric.

In order to avoid the formation of a fringe in producing fabrics by the insertion of double picks it has been proposed to utilise a catch thread or sewing thread cooperable with the loop end and against which the double loop is drawn taut, such proposal having provided a satisfactory solution to the problem.

In the art it is standard practice to provide a rapier loom to one or other of a limited range of nominal sizes, and to utilise a particular loom in the production of fabrics of a specific width appropriate to the nominal loom size and varying but little from that width, the possible variation being determined by the range of adjustment widthwise of the warp of the catch thread mechanism.

In the case of a wide loom, say for producing fabrics of between 2 and 2.25 metres in width, the loom utilisation is ordinarly low in that the primary commercial requirement is for belting fabrics in the width range of between 1 to 1.125 metres.

Accordingly the wide loom may lie idle for substantial periods.

In an endeavour to increase the extent of utilisation of the wider looms, such looms are used in the production of a corresponding wide fabric, such fabric being subsequently slit in the warp direction thereof to give two or more individual fabrics each of a requisite width. However, in such event the security of the selvedge edges formed by slitting may not be wholly satisfactory, and the application of the belting, without some form of edge reinforcement is accordingly limited.

The object of the present invention is to provide a rapier loom of the kind in which weft yarns are inserted as loops, thus to give a double weft on each insertion, wherein provision is made for a substantial variation in the width of fabric produced thereon without the need for slitting an "overwidth" fabric.

Thus, according to the present invention there is provided a rapier loom adapted for the insertion of double weft picks from a continuous weft supply at each loom operation, characterised by a rapier motion at each side thereof and a double selvedge system intermediate the sides of the loom, at least one of said rapier motions being selectively adaptable to insert a double loop throughout the full loom width or throughout a part only thereof and the selvedge system being removable from its operative position intermediate the sides of the loom, there being a selvedge system suitable at that side of the loom remote from the said slectively adaptable rapier motion.

That selvedge system sitable at that side of the loom remote from the selectively adaptable rapier motion may be the same as or may be different from the selvedge system provided intermediate the loom sides.

The invention will now be described further, by way of example only, with reference to the accompanying drawings illustrating one embodiment thereof and in which: Fig. 1 illustrates, in diagrammatic manner, the operation of a rapier loom in inserting a double weft into a warp shed and shows the cooperation between the selvedge shuttle and weft loop in forming a fast selvedge at that edge of the cloth remote from the rapier mechanism; Fig. 2 is a diagrammatic side elevation of a rapier loom constructed in accordance with the invention; Fig. 3 is a diagrammatic front view of the structure shown in Fig. 1; Fig. 4 is a diagrammatic plan view of the loom, various parts having been omitted in the interests of clarity.

Figs. 5 and 6 are diagrammatic illustrations of full width and half width rapier operations, respectively, and further show the manner in which the breast beam angles are separated in the double fabric mode of operation; and Figure 7 is a diagrammatic illustration, drawn to a larger scale, of a rapier drive system of a kind suitable for substantial adjustment of rapier stroke.

Referring to the drawings, and particularly to Fig. 1 thereof, a weft loop 11 is inserted into a warp shed 12 by a reciprocable loop 13 with which weft yarn 14 from a yarn package 1 5 is engaged and, on forward motion, carries such yarn through the shed to a position in the path of movement of a selvedge shuttle 1 6. The nose 17 of the shuttle takes the loop 11 from the rapier 1 3 and passes such loop 11 round the selvedge yarn package 1 8 carried by the shuttle 1 6 to thread the selvedge yarn 1 9 through the loop 11 , the loop 11 being held against withdrawal from the shed 1 2 on rapier retraction by a reciprocable finger 20 positioned adjacent the edge 21 of the warp 22.

On withdrawal of the rapier 13 and on a change of shedding of the warp yarns, the sley 23 pivots to effect beat up of the weft loop 11 into the fell 24 of the cloth 25 and swings back out of the path of movement of the rapier 1 3 for insertion of the next weft loop, the selvedge shuttle 1 6 and the finger 20 having withdrawn to respective opposite sides of the path of movement of the rapier 13.

The foregoing operation is conventional in the art.

In accordance with the invention the principle of operation as illustrated diagrammatically by Fig.

1 is applied to a rapier loom in such manner as to allow of the production of the single fabric up to the full nominal width of the loom or of two (or more) fabrics each of a width substantially less than such nominal width and collectively of a width less than that width.

Thus, referring now to Figs. 2 to 4 of the accompanying drawings, a rapier loom 30 receives a sheet of warp yarns 31 from a creel, not shown, via a let off motion 32, the woven cloth 33 passing from the loom to a take-up reel 34.

The warp yarns 31 form two spaced, parallel warp yarn systems 35, 36 (Figs. 3 and 4), the two systems, in the embodiment illustrated, being of subtantially the same width and being symmetrically positioned widthwise of the loom.

A rapier mechanism, indicated simply as the forward end of the rapier37, is provided at each side of the loom and each such mechanism 37 cooperates with a respective selvedge shuttle and finger arrangement 38 provided in the space between the individual warp yarn systems to introduce a selvedge yarn (not shown) into the weft loop to hold the same against withdrawal, the shuttle and finger arrangements 38 being anaiogous to those conventionally used in the art and differing therefrom, if at all, only in minor regards.

In order to allow of uninterrupted motion of the selvedge shuttles and fingers of the arrangements 38 in circumstances where the loom is being utilised to weave two side-by-side fabrics, the breast beam angle 39 of the loom is separated in two parts 40, 41 at a position in register with the space 42 between the two warp yarn systems 35, 36, the respective parts 40, 41 being movable to and from abutting end-to-end engagement as is illustrated diagrammatically in Figs. 5 and 6 of the drawings. If necessary, like provision may be made for division of the reed 43 (Fig. 2) and for the separation of the two parts thereof as required.

In the mode of operation illustrated by Figs. 2 to 4 and Fig. 6, the stroke of the individual rapiers 37 is such as to bring the forward ends thereof into co-operating relationship with a respective one of the selvedge shuttles. in order to provide for a substantial adjustment in the stroke of a selected one of the rapiers and thus enable the same to be used selectively in the production of a wide or a narrow fabric, in relation to the nominal width of the loom, a drive mechanism as illustrated in Fig. 7 of the drawings is proposed.

Referring now to Fig. 7, the drive mechanism comprises an epicyclic gear arrangement 44 drivingly connected at the output side thereof into a peripherally toothed wheel 45 engaged with a rack 46 secured to the underside of the rapier 37 and driven from a drive shaft 47 through a cam and cam follower combination 48 operating to effect reciprocation of a drive rod 49 connected to an input arm 50 which constitutes the input member of the epicyclic gear arrangement 44, the drive rod 49 being positionally adjustable longitudinally of the input arm 50 so as to vary the angular motion of the epicyclic gear arrangement 44 and thus the stroke of the rapier 37.The cam and cam follower combination 48 includes two conjugate cams 51, only one of which is shown, each with a respective follower 52, and serves to ensure positive and controlled motion both of the drive rod 49 and of the rapier 37 in each direction of movement thereof The motion of the cam followers 52 is transmitted to the drive rod 49 through a pivotted drive lever 53 relative to which the cam followers are angularly fixed, the said drive lever 53 being articularly connected to the lower end of the drive rod 49.For limited movement of the rapier consistent with the production of a fabric of substantially lesser width than the nominal width of the loom the connection betwen the drive rod and the input arm is positioned towards the remote end of the latter, whilst for reciprocatory motion across the full width of the loom the connection is made closer to the epicyclic gear arrangement.

In use of the rapier loom as herein proposed when it is required to produce two separate fabrics, each side of the loom operates to form a respective fabric, each rapier motion cooperating with a respective selvedge system to form a fast selvedge at the "innner" edge of the fabrir, the selvedge at the "outer" edge of each fabric being secure by virtue of the crossing of the warp yarns in relation to that run of the double loop which connects with the continuous weft supply on shedding of the warp yarns.

In the event that a fabric is required of a width consistent with the nominal width of the loom, only one rapier motion is utilised, the traverse thereof being suitably increased, and the double selvedge mechanism is shifted from its operative position intermediate the sides of the loom. A selvedge mechanism is provided for cooperation with the operative rapier motion, which mechanism may be a part of the double selvedge mechanism or otherwise, and serves to insert a catch thread to hold the remote end of the double pick.

By means of the structure as herein envisaged we are able to maximise utilisation of a wide rapier loom, and to provide a facility, in a single loom, for electing between the production of fabrics to the full width of the loom or to a substantially lesser width than that of the loom whilst providing satisfactory selvedges at each edge of the fabric or fabrics.

Whilst in the ordinary course of events the individual fabrics would be of like construction and would require similar weaving conditions as to warp tension, weave structure and warp width, by using a Jaquard mechanism for warp control rather than the heald frame shedding mechanism of the structure herein disclosed so the invention may allow of the side-by-side weaving of fabrics of different character, at least as regards cloth construction subject to compatability as between, for example. warp tension and warp yarn utilisation of the separate "fabrics" if a common let off mechanism and take up roll are used.

Claims (5)

1. A rapier loom adapted for the insertion of double weft picks from a continous weft supply at each loom operation, characterised by a rapier motion at each side thereof and a double selvedge system intermediate the sides of the loom, at least one of said rapier motions being selectively adaptable to insert a double loop throughout the full loom width or throughout a part only thereof and the selvedge system being removable from its operative position intermediate the sides of the loom, there being a selvedge system sitable at that side of the loom remote from the said selectively adaptable rapier motion.

2. A rapier loom as claimed in claim 1 ,further characterised in that the said double selvedge system is movable from its position intermediate the sides of the loom and is locatable at a position at that side of the loom remote from the selectively adjustable rapier motion for cooperation with such motion at such latter position.

3. A rapier loom as claimed in claim 1 or 2, wherein the loom includes a breast beam comprising a plurality of beam angles selectively arrangeable in abutting or in spaced apart end-toend disposition, tye gap between adjacent ends of the beam angles when arranged in spaced apart relationship being in register with the double selvedge system as located intermediate the sides of the loom.

4. A rapier loom as claimed in any one of the preceding claims characterised by a drive means for each selectively adaptable rapier motion which includes a pivotal input arm drivingly connected with a step up gear arrangement having an output member operatively connected with a rack secured to the rapier to effect reciprocating motion thereof, the drive means further including a reciprocable drive rod connectable with the input arm at a selected position longitudinally of such arm in relation to the pivot axis thereof appropriate to the intended stroke of the rapier.

5. A rapier loom as claimed in claim 4, further characterised in that the drive means further includes a cam and cam follower mechanism drivingly connected with the drive rod to effect reciprocation thereof, the cam and cam follower mechanism including conjugate cams and respective cam followers.