GB2210636A

GB2210636A - Knocking-over sinkers in a double-cylinder circular knitting machine

Info

Publication number: GB2210636A
Application number: GB8823368A
Authority: GB
Inventors: Pavel Zahradka; Jiri Jrabanek
Original assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Current assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Priority date: 1987-10-06
Filing date: 1988-10-05
Publication date: 1989-06-14
Also published as: IT8822099A0; DE3831983A1; IT1227231B; GB8823368D0; CS263106B1; CS719987A1

Description

2 2 6 DEVICE FOR KNOCKING-OVER THE STITCHES IN A DOUBLE CYLINDER CIRCULAR

KNITTING MACHINE

DESCRIPTION:

The invention relates to a device for knocking-over the stitches in a double-cylinder circular knitting machine for the production of socks goods.

Double-cylinder circular knitting machines are known, where the fabrics are knitted in combination of rib and purl stitches by lower or upper needles. Rib stitches being knitted on lower needles are knocked-over by the knock-over sinkers, while purl stitches being knitted on upper needles are only drawn over the presser sinkers so that when knitting more purl stitches beside each other, sticking of the purl stitches into opened latches of upper needles takes sometime place when sinking.

A device is known from the Czechoslovak Author's Certificate No. 141,210 which solves this problem so that purl stitches are drawn over the lower edges of the hooks of the knock-over sinkers and then during passage of the needles into the clearing position they are knockedover. But said device has a disadvantage that between the place of laying the thread and the place of maximum sinking of the needle there is a long distance, which caLies difficulties when plating and the thread is considerably stressed.

The disadvantage of the difficulties when plating is solved by the device according to U.S. Patent No. 4,233,822 where the knock-over sinkers perform double knocking-over. Sinker cam have double opening and closing while during the first closing knock-over of the rib stitches and during the second closing knock-over of the purl stitches takes place. Said second opening and closing, or the projection is arranged in the sinker cam rings under the retracting cam of upper needles moving the needles into the clearing position. Disadvantage of said solution is the fact that the sinker cam rings are considerably complicated and challenging from the point of view of production, further that the device occupies a larger space on the arc-of the needle cylinder and further that double knocking-over takes place and hence stretching of the rib stitches before raising lower needles into the clearing position.

2 The task of the invention is to eliminate the above npentioned disadvantages.

According to the invention there is provided a device for knockingover the stitches in a double-cylinder circular knitting machine for the production of socks goods, coniprising cam rings to control the knockover sinkers provided with hooks to knock-over the stitches, which have in each knitting feed a working edge to open the knock-over sinkers and followed by an edge- to close them and to knock over the stitches, wherein the working edge for closing and to knock-over the stitches is located behind the place where the heads of the upper needles being lowered pass through the plan laid through the lower edges of the hooks of opened knock-over sinkers.- The advantage of the invention is the fact that the design of the sinker cam rings is sirrple and enables the application in the machine where reciprocatory double-feed heel is knitted, because the working edges for opening and closing during reciprocatory run can be placed near each other.

An embodiment of the invention will now be described by way of exarrple, with reference to the accorrpanying drawing. In the drawing a known double cylinder circular knitting machine for the production of socks goods is provided with needles 1 with two hooks which are placed either on lower or upper guiding sliders 2, 3 in the tricks of the lower or upper needle cylinder 4, 5. Under the lower guiding sliders 2 there are known, not shown jacks. Knock-over sinkers 6 cooperate with needles 1 when forming stitches, said knock-over sinkers 6 being controlled by lower and upper sinker cam rings 7 and 8. Right and left stationary and stitch density controlling cams 9, 10 and 9 10 in the first knitting feed are designed to control lower guiding jacks 2 or the needles 1 in the lower needle cylinder 4. The sam cam 12, 13 and 12'0, 13'and 14 are also in the second knitting feed. Shifter 15, stationary and stitch density controlling cams 16 and 17 and retracting cam 18 in the first knitting feed and shifter 19, stationary and stitch density controlling cams 20 and.21 and retracting cam 22 in the second knitting feed are designed to control the upper guiding jacks 3. Retracting cams 18 and 22 are designed to move upper needles 1 into the clearing position, while at a half of the height they are provided with horizontal edge 18 1 and 22 3 Lower cam ring 7 in the first knitting feed is provided with working edge 71 which is designed to open the knock-over sinkers 6.

Said working edge 71 is followed by the working edge 81 of the upper cam ring 8 which serves to close the knock-over sinkers 6 and to knock over the stitches. Said working edge 81 is placed under the retracting c&n 18 before the horizontal edge 18 The beginning of the horizontal edge 18'Ocorresponds to such a height of lowered upper needle 1 when its head is already under the plane laid through the lower edges 6f the hooks of opened knock-over sinkers 6. Place X, when the hooks of the upper needles 1 pass through the plane 19 is before the working edge 81, while said working edge 81 begins at least by pitch t of the needles 1 behind the place X. The course of tlp-hooks of the upper needles 1 is illustrated by a dashed line 20. The course of the hooks of lower needles 1 is illustrated by dashed line 21, while after sinking lower needles 1 are raised above said plane 19 behind the working edge 81 in place Y. Said place Y is again at least by one pitch t behind the working edge 81 under the horizontal edge 180 of the retracting cam 18.

The operation of the above described device when knitting rib and purl stitches is as follows. Needles 1 are set out for example 2:2. Cpening of t}7p-knock-over sinkers due to the action of the working edge 71 of the lower cam ring 7 takes place before sinking the upper and lower needles 1 in the first knitting feed. In this position the tops of the hooks of the knock-over sinkers 6 are in front of the stem of needles 1.- After sinking and after formation of purl and t_ib stitcl-lles by nr--ar.s of stationary and stitch density controlling cam 16, 17 and 10 and 10 the upper and lower needles 1 begin to move in the clearing position, as illustrated by the course of the dashed lines 20 and 21. Upper needles are in the place X lower under said plane 19, that is sooner than the lower needles 1 are raised above it in the place Y. Between the place X and Y the knock-over sinkers 6 are closed by mans of the working edge 81. Because the upper needles 1 or their hooks are already lowered under the plan 19 and the hooks of lower needles 1 are not yet above said plane 19, catching of the purl and rib stitches and their knock-over takes place. Raising of the lower needles 1 above the plane 19 takes place only after knocking-over of the stitches and raising of the lower needles 1 cannot cause raising of the purl stitches from the hooks of the knock-over sinkers 6 because they are already closed.

4 The same procedure takes place in the second knitting feed when knitting purl and rib stitches in a course. Safe catching of the stitches in the knock-over sinkers is given also by that the working edge 81, or the place Y, are up to one pitch t of the needles 1 behind the place X, or behind the working edge 81 and this ensures also that also the sinker loops from the thread between the upper and lower needles 1 get into the hooks of the knock-over sinkers in case of 1:1 set-out.

Q

Claims

CLAIMS:

1. A device for knocking-over the stitches in a double-cylinder circular knitting machine for the production of socks goods, corrprising cam rings to control the knock-over sinkers provided with hooks to knock-over the stitches, which have in each knitting feed a working edge to open the knock-over sinkers and followed by an edge to close them and to knockover the stitches, wherein the working edge for closing and to knock-over the stitches is located behind the place where the heads of the upper needles being lowered pass through the plane laid through the lower edges of the hooks of opened knock-over sinkers.

2. A device according to claim 1, wherein the working edge for closing and for knocking-over the stitches is located before the place where the heads of the lower needles being raised pass through the plane being laid through lower edges of the hooks of opened knock-over sinkers.

3. A device according to claim 1 or 2, wherein the place where the heads of the lower needles being raised pass the plane laid through the lower edges of the hooks of opened knock-over sinkers is under the horizontal edge of the retracting cam of the upper needles into the clearing position, while the working edge for closing an for knocking-over the stitches is before said horizontal edge.

4. A device for knocking-over the stitches in a double-cylinder circular knitting machine for the production of socks goods, substantially as hereinbefore described with reference to the accoirpanying drawing.

1 Published 1988 at The Patent office. cl.ee House. 6671 High H01b=--London WC1R 4TP. Further copies mkv be obtained from The Patent Office, Sales Branch. Si Mary Cray. orpl,,9,cn, Ken BR55 3RD oy M=plex techraques Iltd. St Mar., 'rav, Kent. Con 1'8".