GB2193230A

GB2193230A - Density control device in a circular knitting machine

Info

Publication number: GB2193230A
Application number: GB08717947A
Authority: GB
Inventors: Pavel Uhlir
Original assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Current assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Priority date: 1986-07-29
Filing date: 1987-07-29
Publication date: 1988-02-03
Also published as: GB8717947D0; IT1222160B; CS568686A1; CS255035B1; IT8721481A0; DE3724823A1

Description

GB2193230A 1 SPECIFICATION ences the adjustment of the density contol cam

automatically during knitting.

Density control device in a circular knitting The device according to the invention will machine now be described, by way of example, with reference to the accompanying drawing.

The invention relates to a density control de- A known single-cylinder circular knitting ma vice in a circular knitting machine for the prochine for the production of hosiery and the duction of hosiery and the like goods. like goods is provided with a needle cylinder It is known that in hosiery multi-feed, circu- 1 in the longitudinal tricks 2 of which there lar knitting machines on the fabric there ori- 75 are located knitting needles 3 and under the ginate undesirable transverse stripes, originat- needles there are, not shown, jacks. Known ing due to irregular consumption of the knock-over sinkers 4 cooperate with the knitt threads in individual knitting feeds and pre- ing needles 3. To create stitches the knitting senting themselves as regularly alternating needles 3 are controlled by stitch cams 5 with courses with different length of the stitches. 80 respective counter cams 6 arranged in indivi Stitch length and thus the speed of the thread dual knitting feeds. Each stitch cam 5 or take-off in respective knitting feed is given by counter cam 6 is fixedly located on a carrier the depth of sinking the needle hooks under 7. Carrier 7 is placed on pins of rocker levers the knock over level and it is also influenced 8,9 which are by their pins located swingably by the tension of the taken-off thread from 85 in a stand 10. The stand 10 is fixedly ar which the stitches are formed. Sinking of the ranged on a flange 11 of the machine. Further needles is given by the density control cams in the stand 10 there is fixedly arranged an and the thread tension is influenced by the electric motor 12 either as a step motor or a adjustment of the thread brakes and by the servomotor and the like. On the shaft of the quality of thread winding on the bobbin. Be- 90 electric motor 12 is mounted a lever 13 which cause even insignificant changes in the depth is kinematically connected with the prolonged of needle sinking or in the tension of the end of the rocker lever 9 by means of a tie taken-off thread significantly influence the rod 14.

stitch length, it is necessary to check the fab- Circular knitting machine is provided with a ric quality sometimes even several times durcontrol microcomputer 15 to which is con ing one work shift and to adjust the density nected the electric motor 12 via a lead A.

control cams, eventually thread braking. Ad- Further to the input of a control microcompu justment of the density control cams espe- ter 15 is connected a sensor 16 via a lead B, cially in multi-feed knitting machines is difficult the sensor measuring the speed of the thread and time consuming. It is performed so that 100 P being supplied by a guide 17 from a bobbin the length of the stitches is checked, or by 18 on the machine bobbin- stand. The memory means of a special hand carried apparatus by of the control microcomputer 15 contains means of which the speed of the yarn take-off coded speeds of the thread P supplied for in individual feeds is measured. Then in de- individual sections of knitting and further, with pendence of measured values adjustment of 105 regard to said speeds, also axial positions of the density control cams is performed manu- each stitch cam 5 are coded, that is by angu ally by means of the adjustment screws. Due lar position of the shaft of the electric motor to the difficulties with laborious adjustment of 12.

the densities in multi-feed knitting machines During knitting, thread P is drawn towards there is a large portion of the fabrics with 110 the sensor 16 which measures its speed of transverse stripes. take-off and transfers it in coded form to the The object of the invention is to eliminate control microcomputer 15. Said information on the above mentioned disadvantages. measured speed is compared here with the According to the invention there is provided information coded in the memory and in case a density control device in a circular knitting 115 of a difference in information the control mi machine for the production of hosiery and the crocomputer 15 sends respective signal into like goods, compris ing a stitch cam controlled the electric motor 12, which then by means axially movably by a kinematic transmission by of kinematic transmission performs respective means of an electric motor by a control mi- correction of axial position of the stitch cam 5 crocomputer of the machine, wherein it com120 and thus also a correction in the fabric den prises a sensor to measure the speed of sity.

thread supplied to the needles connected. to The above mentioned operation is described the control microcomputer of the machine. only for thread P supplied into one knitting The advantage of the invention is the fact feed. The density is controlled in the same that the values of the speed fed by the scan- 125 way and by the same means also in other ner into the control computer are during knitt- knitting feeds. Sensor 16 is either permanently ing compared with the speed entered for re- arranged in the outfit of the machine, or it can spective zone of knitting into the programme be used only when checking, when the opera and on the ground of said comparison pulses tor connects the sensor to the control micro are sent into the electric motor which influ- 130 computer and performs manual measurement 2 GB2193230A 2 of the speed.

Claims

1. A density control device in a circular knitting machine for the production of hosiery and the like gooods, comprising a stitch cam controlled axially movably by a kinematic transmission by means of an electric motor by a control microcomputer of the machine, wherein it comprises a sensor to measure the S I peed of thread supplied to the needles con nected to the control microcomputer of the machine.

2. A density control device in a circular knitting machine, substantially as hereinbefore described with reference to the accompanying drawings.

Published 1988 at The Patent office, state House, 66/71 High Holborn, London WC 1 R 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Burgess & Son (Abingdon) Ltd. Con. 1/87.