GB2031956A - Yarn stop motion means for a knitting machine - Google Patents

Abstract

In the knitting of articles of clothing on multi head knitting machines the breakage of one yarn while a garment is being knitted results in a spoilt garment and if the machine continues to operate after it has finished that garment further spoilt garments will be produced until that machine has been stopped. The present stop motion is actuated if one of the yarns being fed to the knitting head breaks to prevent the machine from knitting another garment until the broken thread has been repaired but does not stop the machine until the spoilt garment is finished. A member rotated by the running yarn which holds a micro switch into one of two positions and if a yarn is running the micro switch which is held in the position permits the machine to be activated but in the event of the yarn not running, then the micro switch is operated into a position in which the machine is stopped at the end of a garment knitting cycle. <IMAGE>

Description

SPECIFICATION Yarn stop motion means This invention relates to yarn stop motion means and is particularly concerned with providing an improved stop motion means for a running yarn being fed into a circular knitting machine.

It will be appreciated that in the formation of many articles of clothing and in particular, stockings, tights and similar garments, which are made on circular knitting machines, that the garments are made relative'ly swiftly as the machines will have several knitting positions, that is to say that yarn is fed to the needles at more than one position around the needle cylinder.

It will also be appreciated that should one of these yarns cease to feed, i.e. by a break or by other means, then the garment is unsatisfactory. It is accepted that shou Id one yarn break, that particular garment is unsatisfactory. What it is necessary to achieve is to have means which will prevent the machine from continuing to knit subsequent garments, when one of the many yarns being fed into the machine breaks.

British Patent 1 423 538, Pretty Polly Limited, describes one known type of stop motion mechanism for a circular knitting machine of the kind with which the stop motion mechanism of this invention is also concerned. With the device described in 1 423 538, the stop motion action occurs immediately a yarn breaks. According to the present invention, when a yarn breaks the machine will continue to operate until such time as it has completed one cycle and has arrived at a point where it is about to startthe knitting of another new and complete article. If at that point, a yarn has broken during part of the knitting of the previous article, the machine will not then operate.

The present invention provides stop motion means for a running yarn, in conjunction with a knitting machine, comprising a member rotatably driven by a running yarn, a micro switch for actuating a stop motion circuit, means interconnecting the said member and the micro switch such that when the member is rotated it actuates the micro switch to a first predetermined position, and holds the micro switch in said position, means for releasing the micro switch to a second predetermined position, at which the stop motion circuit is activated and means for allowing the micro switch to adopt the second predetermined position in the event of yarn not rotating said member.

Desirably, the member is a wheel around which the yarn runs and the micro switch has a feeler which is contacted by a peg or the like on the side of the wheel. As the wheel rotates it strikes the feeler and moves the micro switch to said first of the predetermined positions. An arm is provided for hold ing the feeler in the position to maintain the micro switch in said first of the predetermined positions, and means are provided for releasing the arm to allow the micro switch to return to the second of the said predetermined positions from which it will not be displaced in the event of yarn not rotating the said member.

In order that the present invention may be more readily understood, reference is now made to the accompanying drawing in which; Figure 1 is a perspective view of a mechanism according to the present invention.

Figure 2a is a plan view of the apparatus in a first position.

Figure 2b is a side view of the apparatus in the same position as Figure 2a.

Figure 2c is an end view of the apparatus in the said position of Figure 2a.

Figure 3a is a plan view of the apparatus in a second position.

Figure 3b is a side view thereof.

Figure 3c is an end view thereof.

Figure 4a is a plan view of the apparatus in a third position.

Figure 4b is a side view thereof; and Figure is an end view thereof.

Referring first to the figures, a micro switch 1 has a flexible wire feeler 2 extending therefrom, such that on depression of the feeler 2, the micro switch is moved to one of two predetermined positions. When the feeler is at rest it allows the micro switch to adopt the second of the two predetermined positions. In the second of the predetermined positions, the micro switch may be connected in ci mu it provide an earthing for further circuit which provides stop motion or other warning means as desired and which do not form part of the present invention.

When the feeler 2 is depressed the circuit for effecting stop motion of the mechanism or alarm means is not energised. A wheel 3 rotatable about an axis 4 is provided and has yarn 12 running therearound so as to rotate the wheel 3 in a clockwise direction as viewed in Figure 1. The wheel 3 has on one side face thereof, a pin 11 which is adapted to contact in its rotational path the feeler 2 and to depress it. An arm 8 is pivoted about a pin 10 on a support bracket 13, a flexible cable 9 having an operating element 7 extends beyond a stop 5 and is connected to the arm 8.A coil spring 7 is interposed between the bracket 5 and the arm 8 so as to bias the arm 8 into the position illustrated in Figure 1, in which position the lower portion of the arm 8 is in the path of the feeler 2, so as to displace the feeler 2 itself in the path of the pin 11 and such that when the pin 11 depresses the feeler 2 downwardly, the feeler 2 is then caught beneath the lower surface of arm 8. On operation of the cable 7 against the influence of the coil spring 6, the arm 8 is moved into a position in which it is substantially flush with the bracket 13 and thus releases the feeler 2 to allow the micro switch to adopt the second of the said two predetermined positions.

In Figure 2a, it will be observed that the arm 8 is flush with the bracket 13 and the feeler 2 is substan tiaily in contact with the sides of the said arm.

In Figure 3a, 3b, and 3c, the arm has been displaced to the position illustrated in Figure 1 such that the pin 11 will now contact the feeler 2 and with further rotation thereof, will displace the feeler 2 beneath the lower surface of the arm 8 where it is held by said surface from returning to the second of the predetermined positions. In such position the feeler 2 operates the micro switch to the first of the said predetermined positions and thus deactivates the stop motion circuit.

The invention is particularly suitable for yarns such as elastomeric yarn being fed into the welt of ladies stockings orto the waist band of pantihose or to other articles of clothing, particularly of the stocking, socks, leotards, or tights nature, which require an elasticated portion and in which an elastomeric yarn is fed in to provide elasticity at that part.

According to the nature of the knitting machine making the said garments, there will be provided a stop motion circuit such that should any other yarns break, the machine will stop, and there is also provided at the beginning of each cycle for knitting the article in question, a dead period in which all the stop motion circuits are rendered inoperative, this is necessary in order to establish the yarn on to the needles and their first course and it is at this stage that a cam on the patterning drum of the machine will be used to activate the cable 7 and to return the arm 8 to the position in which it is flush with the bracket 13, thus, equally rendering the stop motion mechanism according to this invention in the operative position, that is to say the second of the aforementioned predetermined positions.

If at that point in time, a yarn is running around the wheel 3 so that the feeler 2 is moved to the first of the said predetermined positions, afterthe machine has knitted the first one or two courses, the machine will knit nothing further because the micro switch will have activated the stop motion circuit.

It is thoughtthatthe present invention is particularly suitable for a running elastomeric yarn in the knitting of articles such as those hereinbefore mentioned.

Claims (6)

1. Stop motion means for a running yarn in conjunction with a knitting machine comprising a member rotatably driven by a running yarn, a micro switch for actuating a stop motion circuit means interconnecting the said member and the micro switch such that when the member is rotated it actuate the micro switch to a first pre-determined position and holds the micro switch in said position; means for releasing the micro switch to a second pre-determined position at which the stop motion circuit is activated and means for allowing the micro switch to adopt the second pre-determined position in the event of yarn not rotating said member.

2. Stop motion means according to claim 1 in which the member is a wheel around which the yarn runs and rotates said wheel, said wheel having a peg or the like on the side thereof which peg during rota tion of the wheel contacts a feeler secured to the micro switch, so as to displace the micro switch from the second of said pre-determined positions to the first of said pre-determined positions.

3. Stop motion means according to claim 2 having an arm for holding the feeler in the position to maintain the micro switch in said first of the predetermined positions.

4. Stop motion means according to claim 3 having means operable at the end of a knitting cycle for releasing the arm to allow the micro switch to return to the second of said pre-determined positions.

5. Stop motion means according to claim 4 which comprise a cable operated by patterning means of the knitting machine.

6. Stop motion means for use in conjunction with the knitting machines substantially as described herein with reference to the accompanying drawings.