GB2256441A

GB2256441A - Thread guide for circular knitting machines

Info

Publication number: GB2256441A
Application number: GB9211654A
Authority: GB
Inventors: Milan Fucik
Original assignee: Uniplet AS
Current assignee: Uniplet AS
Priority date: 1991-06-07
Filing date: 1992-06-02
Publication date: 1992-12-09
Anticipated expiration: 2012-06-02
Also published as: JPH05186944A; ITMI921383A0; GB2256441B; CZ279623B6; GB9211654D0; ITMI921383A1; IT1270322B; CZ175191A3

Abstract

A thread guide (5) designed especially for double-cylinder circular knitting machines is mounted for swinging about a pivot (91), and is secured to a tierod (6) of a piston of a pneumatic power cylinder (7) which is supported to pivot with the threadguide. When the cylinder advances and retracts the guide (5) an inclined face of the latter engages a ball (10) to cause pivoting of the guide and cylinder assembly in association with a biassing spring (81). <IMAGE>

Description

THREAD GUIDE FOR CIRCULAR KNITTING MACHINES The invention relates to a pivotally mounted thread guide especially designed for being installed in double-cylinder circular knitting machines and having a foremost portion for supplying needles with thread.

It is known that thread guides for being used in double-cylinder knitting machines for hosiery manufacture are mounted, as a rule, for swinging in horizontal plane so that the thread may intersect the path of needles and be engaged by severing shears.

Owing to their motion, such thread guides take up disadvantageously a considerable space, and devices for manufacturing them are very complicated.

It is an object of the present invention to eliminate the above-mentioned drawbacks of prior art and to provide an improved thread guide for a machine comprising a thread severing device with a circular saw.

The idea of the invention, the features of which are set forth in the appended claims, consists in that the foremost portion of the tread guide is fixedly attached to a tierod on the piston of a pneumatic power cylinder installed on the pivoted guide part.

An advantage of the invention is in that the pneumatic means for controlling the thread guide are immediately built in itself so that well-known cam systems can be omitted. This, further, is important with machines whose thread severing devices comprise a circular saw. Another advantage consists in that the pneumatic elements are activated by magnets so that the guide is suitable for being installed in electronically controlled machines.

A preferred example of the thread guide according to the invention will hereinafter be described with reference to the accompanying schematic drawings wherein Fig. 1 shows the guide in operative position; and Fig. 2 shows the same in inoperative position.

As can be seen in the drawings, a well-known double-cylinder knitting machine for manufacturing hosiery comprises an upper cylinder 1 and a lower needle cylinder 2 fitted with double-headed needles 3. At the top end of said lower cylinder 2 is mounted a circular, thread severing saw 4 which is associated with a pneumatic nozzle and a stationary knife (not shown).

Although any of knitting systems has usually a plurality of thread guides, it is sufficient, for the purpose of the present invention, to show and describe here only one of them, since the operation of the other is identical.

The actual tread guide consists of two portions.

The foremost position 5 has a cam 51 in which there is fixed a pin 52 having at its free end an eye 53 for bringing thread to needles 3. In the cam 51 is screwed a tierod 6 secured to the piston of a pneumatic power cylinder 7 so that said tierod 6 actually constitutes carrying means of said foremost portion 5. The pneumatic power cylinder 7 is fixed in a holder 8 mounted for swinging about a pivot 91 provided in a stand 9.

Irrespective of its position, the cam 51 bears always on a ball 10 supported on a grub screw 11 screwed in a bore provided in the stand 9. The latter is secured by means of a bolt 12 to a support 13.

The pneumatic power cylinder 7 communicates via a hose 71 with a source of superatmospheric pressure air of which operation is controlled e.g. by an electromagnetic valve (not shown).

In operation, which means when needles 3 are fed with thread, the pneumatic cylinder 7 is supplied with pressure air so that the piston tierod 6 is held in its foremost position. The cam 51 bears by its lowermost surface on the ball 10 so that the guide is held by said ball in its operative position against the action of a thrust spring 81.

In case the pressure air supply to the pneumatic cylinder 7 is cut off, the piston tierod 6 is displaced into the rear-most position, i. e. inoperative one, so that cam 51 rolls on the ball 10 until it bears thereon by its recessed surface (Fig. 2). Simultaneously, due to this motion, the thread guide, or better the holder 8 is swung by said thrust spring 81 about the pivot 81 so that the eye 53 will be displaced from the needle engaging position to the inoperative one.

Needless to say that it is possible to variously modify some elements of the guide, provided the relationship thereof to the thread severing means remains unaffected. Thus, for instance, the ball 10 may be replaced by a stationary stop or the like. In case of using well-known mechanical thread severing means of double-cylinder machines the guide may even be mounted for swinging in horizontal plane.

Claims

1. A thread guide, especially for being used in a double-cylinder circular knitting machine, which is pivotally mounted and comprises a foremost portion for supplying needles with thread, the guide being characterized in that the foremost portion (5) is fixedly attached to a tierod of a pneumatic power cylinder (7) which is supported on the pivoted guide part.

2. A thread guide according to Claim 1, wherein its foremost portion (5) is provided with a cam (51) adapted for bearing, in all of the guide positions, on a stop such as a ball (10).