GB2167453A - Pattern control in a flat knitting machine - Google Patents

Abstract

A flat knitting machine comprises two knitting bed pairs arranged one behind the other and a plurality of knitting carriages circulating around the bed in one direction. Wrap-plating threads 3 are each supplied from a spool at an end of the machine, fed through an associated brake (5) and retraction device (6) and guided immediately above the needle beds by a member (8), which has a thread guide eyelet and is inserted in place of a knitting needle in the non-working needle bed, to a wrap thread insertion device (10) mounted on said bed. The insertion device (10) has a thread guide which is movable transversely to the needles by an entraining member disposed on the knitting carriage and is positionable in front of or behind the expelled knitting needles by feeder parts. The thread guide is, after laying of the thread, brought into its initial setting against the carriage running direction by way of toothed racks and a toothed wheel. <IMAGE>

Description

SPECIFICATION Pattern control in a flat knitting machine The present invention relates to a flat knitting machine, especially a machine adapted for production of plaited patterns.

Pattern devices in flat knitting machines with two needle bed pairs arranged one behind the other and knitting carriages circulating thereover in one direction are known. The needle selection according to pattern takes place by way of a pattern wheel, which is arranged on each knitting carriage and settable before the running into one of the needle bed pairs, pattern pressure strips disposed on the knitting carriages, and spring pins, which co-operate with these and are connected with the needles of the beds. The desired thread selection takes place by way of a thread changing device also disposed on each knitting carriage. The feeder part resetting and the actuation of the pressure strips and the thread changing device take place through the control device of the knitting machine on each run of the knitting carriage over the two needle bed pairs.The yarn spools co-rotate on each knitting carriage.

These pattern devices permit the production of a variety of single-colour and multi-colour Jacquard and hook-over patterns, but not the production of plaiting and inlay patterns without appreciable performance loss due to use of only one thread guide for each knitting carriage at a time.

Aithough it is possible to produce inlay or plaited knitware on a flat knitting machine having reciprocating knitting carriages without appreciable performance loss by way of additional thread guides, the travel limiters of which are positioned and reset by way of spindles or chains by means of stepping motors or similar according to the desired plaiting or inlay motif, and a single needle selection of the knitting needles, arrangements of that kind are not transferrable to flat knitting machines with circulating knitting carriages, because the thread guides are carried on the carriages and thereby cannot be brought back into their initial setting in the running knitting row.

There is thus a need for a device which makes possible the production of plaited patterns with least possible performance loss and constructional complication in a flat knitting machine with circulating knitting carriages. Desirably, such a device should be operable by control means of the machine without restriction and with complete utilisation of the existing pattern possibilities, without variation of the existing thread feed principle inclusive of the spool arrangement on the knitting carriage, without variation of the existing feeder part arrangement and without obstruction of the needle orfeeder movements for the normal knitting operation according to pattern.

According to the present invention there is provided a flat knitting machine adapted for production of plaited patterns and comprising two needle bed pairs arranged one behind the other, a plurality of knitting carriages movable to circulate around the needle bed pairs in one direction and cooperable with control means disposed at a fixed location in the machine, a plurality of sinkers inserted into a non-working one of the beds in place of some of the needles thereof and provided with guide eyelets for guiding a plaiting thread above the bed, plaiting thread spool support and feed control means arranged in a fixed location at an end of the machine, a plaiting thread insertion device which is mounted on the needle bed above a region thereof provided for plaiting and which is provided with a plaiting thread guide positionable in front of or behind and movable transversely to the axial direction of needles expelled from the bed, and an entraining member arranged on each carriage and actuable by the control means to effect said transverse movement of the plaiting thread guide on movement of the respective carriage.

In a preferred embodiment, the knitting machines, with two needle bed pairs arranged one behind the other, has a plurality of knitting carriages which circulate around the beds in one direction and which each carry knitting and hook-over feeders, yarn spools, a thread-changing device and control elements actuating the feeder parts and threadchanging device and co-operating with a control device disposed in fixed location at the knitting machine. For the production of plaited patterns, spool mounts for the reception of plaiting thread spools with associated thread brake, thread retraction device and thread guide eyelets are arranged additionally in fixed locations at the end faces of the knitting machine, the threads of which are fed to a plaiting thread insertion device by way of sinkers with thread guide eyelets inserted instead of knitting needles above the not operating needle bed.The insertion device is inserted into the needle bed above the needle bed region provided for the plaiting and is movable transversely to the longitudinal direction of the needle by an entraining member arranged at the knitting carriage and actuable by the control device of the machine. The insertion device preferably comprises two side walls, which are connected with each other by a plate inserted into a respective needle channel, in place of knitting needles, in the not-operating needle bed and in grooves of which slide two rails contructed as toothed racks with abutments for engagement by the entraining member. The two toothed racks in that case are operatively connected with each other by way of a toothed wheel or pinion disposed on the plate. One of the rails carries the plaiting thread guide.

Preferably, the plaiting thread guide is contructed at its forward end as perforated needle and slides in a groove of the last-mentioned rail. By way of a foot thereof, it can be brought by feeder parts arranged on the plate in front of and behind the knitting needles selected according to pattern.

The thread guide eyelets projecting out of the needle bed and the plaiting thread insertion device are preferably arranged nearthe casting-off edge of the needle beds above and not obstructing the feeder parts acting on the needle feet. The sinkers with the thread guide eyelets as well as the side walls of the plaiting thread insertion device are preferably provided, for rigid securement in the needle bed, at their upper sides with dovetailshaped recesses corresponding to the needle rails.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings, in which: Fig. 1 is a schematic front elevation of a knitting machine embodying the invention; Fig. 2 is a sectional view of part of needle bed of the machine, showing a sinker; Fig. 3 is a view of a plaiting thread insertion device of the machine; Fig. 4 is a section through the needle beds and plaiting thread insertion device; Fig. 5 is a sectional view of an entraining device for the plaiting thread guide; and Figs. 6a-g are schematic diagrams showing the positions of the plaiting thread guide during a plaiting operation by the machine.

Referring now to the drawings, there is shown a knitting machine in which are arranged, at both end faces thereof, spool mounts 1 with plaiting thread guides 2. Threads 3 from spools on the mounts pass by way of thread guide eyelets 4, thread brake 5, a thread retraction device 6 and sinkers 8 with thread guide eyelets 9 inserted (horizontally) into the needle bed 7 which is not operating for the production of the plaiting pattern, to a plaiting thread insertion device 10. The sinkers 8 (Fig. 2) are inserted into the needle bed channels in place of those knitting needles which are not needed at the knitware startforthe production of the patent edge.

They have dovetail-shaped recesses and are held rigidly in the needle bed 7 by needle rails 11 and 12.

The thread guide eyelets 9 projecting out of the needle bed and the plaiting thread insertion device 10 are arranged so closely to the casting-off edge of the needle beds and above the feeder parts acting on the needle feet that they do not obstruct these parts during the carriage movement.

The plaiting thread insertion device 10 (Fig. 3) is composed of side walls 15 and 16, which are connected with each other buy a web 17 and a plate 18. The side walls 15 and 16, as in the case of the sinkers 8, are mounted in needle bed channels not needed for the production of the patent edge and are also fastened rigidly in the needle bed 7 by way of the rails 11 and 12. Grooves 19 and 20 for the reception of displaceable rails 21 and 22 are disposed in the side walls 15 and 16. The two rails 21 and 22 are constructed as toothed racks and are operatively connected with each other by a toothed wheel 23. The toothed wheel 23 is mounted in the plate 18. The rail 21 is provided with a groove 24 in which a plaiting thread guide 26 slides. The guide 26 has a foot 27, which is actuable by feeder parts 28, 29 and 30.The feeder parts 28, 29 and 30 are disposed on the plate 18.

The thread guide 26 is constructed in its forward part as a perforated needle and so angled that it can, with minimum occupation of space, get in front of or behind the knitting needles 31 disposed (vertically) in the needle bed operating for the production of the plaiting pattern. Entraining members 32 (Fig. 5), which co-operate with abutments 33 and 34 on the rails 21 and 22, serve for the displacement of the guide 26 along the needle beds.

The entraining member 32 is resiliently mounted in a base body 36 and this is displaceably arranyed in a plate 37 of the knitting carriage. The setting of the entraining member 32 into and out of operation is effected by a spring 38 and a slide 39. The slide 39 is also disposed on the knitting carriage. Its actuation takes place by way of the control device of the knitting machine. Ramps 40 and 41 serve for limitation ofthe plaiting thread guide movement.

When a plaiting pattern is to be produced, the slide 39 is brought into the operative setting by the control device of the knitting machine and the base body 36 with the entraining member 32 is thereby brought into the path of the rails 21 and 22 (Fig. 6a).

Due to the carriage movement, the entraining member 32 acts on the abutment 33 to displace the rail 21 in the carriage running direction (Fig. 6b). As a result, the foot 27 of the guide 26 is also displaced into the region of the feeder part 28 and, by virtue of its shape, brought in front of the knitting needle 31.

In this setting, the guide 26, by means of its end in the form of a perforated needle, lays the thread 3 into the head of the knitting needle 31. It remains in its operative setting due to the feeder part 29 (Fig.

6c).

By means of this needle selecting device, it is possible to keep a number of knitting needles 31 in the inoperative setting. Moreover, the thread 3 is laid in front of only those knitting needles 31 which have been selected by the pattern device. In that case, a wide variety of pattern effects can be achieved through the selectable movement of the needles 31 into full expulsion or tuck setting.

At the end of the plaiting-on operation, the guide 26 is brought back into base setting by the feeder part 30. The entraining member 32 runs up on the ramp 41 and thereby leaves the abutment 33 (Fig.

6d).

Simultaneously with the movement of the rail 21 in the carriage running direction, the rail 22 with its abutment 34 was moved in the opposite sense by the toothed wheel 23. The ramp 32 during the further movement of the knitting carriage now moves into the region of the abutment 34 (Fig. 6e).

Due to the coupling of the rails 21 and 22, the rail 21 moves against the carriage movement and brings the guide 26 back into its initial setting (Fig. 6f). In orderto make this movement possible, the feeder part 28 has the form of a movable tongue which makes it possible for the foot 27 to slide through.

Finally, the entraining member 32 slides onto the ramp 40, whereby the connection between the entraining member 32 and the abutment 34 is interrupted. All the elements of the insertion device 10, which participate in the plaiting operation, are thereby restored to their initial position.

Notches in the rail 22 and a raster 42 arranged on the side wall 15 serve to arrest the insertion device 10 in its respective end settings.

Claims (6)

1. Aflat knitting machine adapted for production of plaited patterns and comprising two needle bed pairs arranged one behind the other, a plurality of knitting carriages movable to circulate around the needle bed pairs in one direction and co-operable with control means disposed at a fixed location in the machine, a plurality of sinkers inserted into a non-working one of the beds in place of some of the needles thereof and provided with guide eyelets for guiding a plaiting thread above the bed, plaiting thread spool support and feed control means arranged in a fixed location at an end of the machine, a plaiting thread insertion device which is mounted on the needle bed above a region thereof provided for plaiting and which is provided with a plaiting thread guide positionable in front of or behind and movable transversely to the axial direction of needles expelled from the bed, and an entraining member arranged on each carriage and actuable by the control means to effect said transverse movement of the plaiting thread guide on movement of the respective carriage.

2. A knitting machine as claimed in claim 1, wherein the insertion device comprises two spaced apart wall members interconnected by a connecting member and mounted in respective needle channels in said one bed, two rails slidably arranged in respective grooves in the wall members and each provided with a toothed rack and a drive abutment, and a pinion mounted on the connecting member and meshing with the racks of the two rails to provide simultaneous and opposite movement thereof, the plaiting thread guide being arranged on one of the rails and the entraining members being engageable with the abutments to effect movement of the rails and thereby of the guide.

3. A knitting machine as claimed in claim 2, wherein the plaiting thread guide has a perforated free end portion and is slidably mounted in a groove in said one rail, feeder elements being arranged on the connecting member and being co-operable with a foot of the plaiting thread guide to effect sliding movement thereof for said positioning in front of or behind the expelled needles.

4. A knitting machine as claimed in any one of the preceding claims, wherein the guide eyelets of the sinkers and the insertion device are arranged adjacent to a casting off edge of the beds and clear of feeder elements acting on feet of the needles.

5. A knitting machine as claimed in any one of the preceding claims, wherein the sinkers and insertion device are connected to needle rails of said one bed by dovetail joints.

6. A knitting machine substantially as hereinbefore described with reference to the accompanying drawings.