GB2172904A

GB2172904A - Double-cylinder circular knitting machine

Info

Publication number: GB2172904A
Application number: GB08605480A
Authority: GB
Inventors: Borivoj Fucik; Pavel Zahradka; Jiri Hrabanek; Milan Petranek
Original assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Current assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Priority date: 1985-03-08
Filing date: 1986-03-05
Publication date: 1986-10-01
Also published as: GB8605480D0; CS249084B1; GB2172904B; FR2578557B1; DE3607403A1; IT8619659A1; FR2578557A1; IT8619659A0; IT1188574B; DE3607403C2

Abstract

The invention relates to a double-cylinder circular knitting machine for the production of socks and like goods with a cam system to control the needles in two knitting feeds arranged for reciprocatory knitting and with sinker cam rings (7, 8) to control the knock over sinkers (6). The invention solves improved knocking over of the fabric in that the sinker rings are provided with a displaceable sinker cam (11) arranged angularly coincident with the clearing edge of the upper clearing cam (20), the sinker cam (11) being engaged to knock over the stitch during the reverse motion of the needle cylinders but being disengaged from action as shown during rotary knitting. <IMAGE>

Description

SPECIFICATION Double-cylinder circular knitting machine The invention relates to a double-cylinder circular knitting machine for the production of sock and the like goods with a cam system to control the needles in two knitting feeds arranged for reciprocatory knitting and with sinker cam rings to control the knock over sinkers.

It is known that in double-cylinder knitting machines formed stitches are knocked over by means of knock over sinkers guided in the sinker cam rings, said knocking over taking place after each knitting feed. Such knocking over takes place and is necessary also during the reverse motion of the needle cylinders during reciprocatory knitting of the heel or of the toe. If the machine is provided with two knitting feeds for reciprocatory knitting, retraction of the knock over sinkers in their limit position takes place twice between the knitting feeds during reciprocatory knitting. Due to said arrangement double retraction of the knock over sinkers takes place also during rotary knitting, whiie the second retraction is for the actual rotary knitting in the lower cylinder not desirable.Especially in case of dense fabrics from thin threads said threads are unduly stressed and rupture of the fabric can thus take place.

The task of the invention is to eliminate said undue stress.

According to the invention there is provided a double-cylinder circular knitting machine for the production of socks and like goods, comprising a cam system to control the needles in two knitting feeds arranged for reciprocatory knitting and sinker cam rings to control the knock over sinkers, a displaceable sinker cam being arranged angularly coincident with the clearing edge of the clearing cam for the needles of the upper needle cylinder to knock over the stitch formed during the reverse motion of the needle cylinders.

The advantage of the invention is the elimination of double knock over of the stitches formed in the lower needle cylinder during rotary knitting by a relatively simple device.

An embodiment of the invention will now be described by way of example, with reference to the accompanying drawings, in which: Figure 1 illustrates the cam system of the upper and of the lower needle cylinder with marked sinker cam rings and the tracks of the needles and knock over sinkers during rotary knitting; Figure 2 illustrates the cam system of the lower needle cylinder with marked sinker cam rings and with the tracks of the needles and knock over sinkers during reverse motion of the needle cylinders; Figure 3 is a partial axial section of the needle cylinders at A-A according to Figure 1; Figure 4 is the same as Figure 3, but at B-B according to Figure 2; and Figure 5 illustrates the control of a displaceable sinker cam.

A known double-cylinder two-feed circular knitting machine for the production of socks and like goods is provided with a lower and an upper needle cylinder 1 and 2 (Figure 3), in the tricks of which there are needles 3 guided by sliders 4, under which there are further, not shown, elements such as jacks, etc. Verge bits 5 in the upper cylinder 2 and knock over sinkers 6 in the lower needle cylinder 1 co-operate with needles 3 when forming the stitches.

Knock over sinkers 6 are controlled by lower and upper sinker cam rings 7 and 8 with spring-loaded cams 9,9', 10 (Figure 1) and by displaceable sinker cam 11 (Figure 2). Right and left stitch cams 12, 13 and 12' and 13' and central cam 14 in the first knitting feed serve to control the lower needles 3 or the sliders 4. The same cams 15, 16 and 15', 16' and 17 are also in the second knitting feed. Retracting cam 18 and stitch cam 19 with clearing cam 20 in the first knitting feed serve to control the upper needles 3 or the sliders 4, and the same purpose is served by the cams 21,22, 23 in the second knitting feed.

Guides 24 and 25 serve to control the latches of the needles 3. Displaceable sinker cam 11 is screwed on a vertically displaceable rod 110 (Figure 5), the lower end of which is gripped by means of transverse screw 111 in a rider 112. The rider 112 is located in an external groove of the internal tube 113 of the needle cylinder 1. One end of a Bowden cable core 114 controlled by a not shown lever of a control drum is gripped in the rider 112. Between the rider 112 and a stationary socket 115 into which is inserted the end of the Bowden cable sleeve 116, there is a compression spring 117 tensioning the core 114. The socket 115 is fixedly mounted on the tube 113.The operating edge of the displaceable sinker cam 11 is arranged under the clearing cam 20 in the upper needle cylinder 2, while for the direction S of rotary knitting before the clearing cam 20 there is a lobe 71 in the lower sinker ring 7 to extend the knock over sinkers 6.

The operation of the above described mechanism is as follows. When knitting a fabric on upper and lower needles 3, for example in 2:2 set-out, the track of the upper needles 3 is marked by the track A of the lower butts of the sliders 4 and the track of the lower needles 3 by the track B of the lower butts of the sliders 4. Motion of the knock over sinkers 6 is marked by the track C of their butts. Displaceable sinker cam 11 is during rotary knitting in the direction S raised up by the action of the compression spring 117 so that it does not interfere with the track of the butts of the knock over sinkers 6. In the first knitting feed rib stitches are formed on the lower needles 3 on stitch cam 13,13' and during lowering of the needles 3 they are knocked over by the knock over sinkers 6 by means of the spring-loaded cam 9', as illustrated in the course of the tracks C and A.Also in the second knitting cam the rib stitches are formed on the lower needles 3 by means of stitch cam 16, 16' and then during lowering of the needles they are knocked over by means of spring-loaded cam 10.

Purl stitches are formed on the upper needles 3 in the first knitting feed on the clearing cam 19 by means of verge bits 5. When raising the needles 3 on the clearing cam 20 opening of the knock over sinkers 6 takes place again by means of the lobe 71 on the lower sinker ring 7, so that parts of threads N (Figure 3) of the purl stitches entrained during raising by the shanks of the upper needles 3 are retained by extended knock over sinkers 6 and cannot slip overthe hooks thereof orwhich do not knock over the stitches, which takes place only when knocking over the rib stitches in the second knitting feed as described above. Also in the second knitting feed the purl stitches are formed by the needles 3 and verge bits 5 on the stitch cam 22.Again during clearing of the upper needles 3 by the clearing cam 23, the second lobe 72 of the lower sinker ring 7 extends the knock over sinkers 6, which again retain the purl stitches, as in the first knitting feed.

During reciprocatory knitting when only the lower needles 3 are knitting, the displaceable sinker cam 11 is set in operation by a command from the control drum. When knitting in the direction S, the stitches are formed in the same way as already described when knitting on the lower needles 3. When knitting in the direction S' all needles 3 follow the track D and the knock over sinkers follow the track E. That means the second knitting feed knits first, the stitches are formed by means of stitch cam 15, 15' and then they are knocked over on the displaceable sinker cam 11, as illustrated in Figure 4. In the first knitting feed the stitches are formed by means of stitch cam 12, 12' and they are knocked over by spring loaded cam 9.

Claims

1. A double cylinder circular knitting machine for the production of socks and like goods, comprising a cam system to control the needles in two knitting feeds arranged for reciprocatory knitting and sinker cam rings to control the knock over sinkers, a displaceable sinker cam being arranged angularly coincident with the clearing edge of the clearing cam for the needles of the upper needle cylinderto knock over the stitch formed during the reverse motion of the needle cylinders.

2. A double-cylinder circular knitting machine according to claim 1,wherein before the displaceable sinker cam under the clearing edge of the clearing cam there is a lobe on the lower sinker ring, said lobe serving to extend the knock over sinkers.

3. A double-cylinder circular knitting machine for the production of socks and like goods, substantially as hereinbefore described with reference to the accompanying drawings.