GB2129448A

GB2129448A - Device for controlling stitch length in circular knitting machines

Info

Publication number: GB2129448A
Application number: GB08327036A
Authority: GB
Inventors: Jilji Matejicek; Jan Trnka; Jindrich Novacek; Vladimir Salomoun
Original assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Current assignee: Elitex Zavody Textilniho; Elitex Koncern Textilniho Strojirenstvi
Priority date: 1982-10-22
Filing date: 1983-10-10
Publication date: 1984-05-16
Also published as: CS229331B1; IT8323365A0; GB2129448B; GB8327036D0; DE3336474A1; DE3336474C2; IT8323365A1; IT1194430B

Abstract

The device comprises an adjustment cam (1) which controls stitch length and a shifting mechanism attached thereto, which comprises a ratchet-pawl mechanism (3, 4). The movable armature of an electromagnet (9), which is controlled by a micro computer (10) of the machine, is pressed directly against the shifting lever (5) of the pawl (4) to rotate the ratchet. <IMAGE>

Description

SPECIFICATION Device for controlling stitch length in circular knitting machines The present invention relates to a device for controlling stitch length in a circular knitting machine for manufacturing hosiery and similar goods, said device comprising an adjusting cam and a shifting mechanism, comprising a ratchet and pawl mechanism, associated therewith.

Devices for controlling stitch length in small diameter, particularly single cylinder knitting machines are known, which use a mechanical drive of the pawl with a constant or adjustable step about one or more ratchet teeth, the latter being coupled with a cam or another tracing device, from which the stitch length is adjusted.

Furthermore, a device is known, which uses a stepping position motor, which substitutes, on the basis of pulses from a program controlled electronically by a micro computer, the power element ratchet-pawl, and the pivot motion of which is transferred to a lever, or the needle cylinder of the machine. However, this device is complicated and unreliable.

The purpose of the present invention consists in removing the above mentioned disadvantage for machines provided with micro computers for controlling the machine operation, this being substantially achieved by arranging that the shifting lever of the pawl is directly acted upon by a movable armature of an electromagnet, which is controlled by the micro computer of the machine.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawing, which represents the whole diagram of controlling from a micro computer to stitch and guard cams.

A single cylinder circular knitting machine for manufacturing hosiery and similar goods is provided with an adjusting cam 1 mounted rotatably on the surface of the control drum 2, besides further known, not represented, stationarily arranged force operational segments.

A ratchet wheel 3 is connected to cam 1, and is engaged by pawl 4, which is swingably mounted on shifting lever 5. Pawl 4 is spring-loaded relative to shifting lever 5 by means of a tension spring 6.

The shifting lever 5 is mounted swingably on shaft 21 of control drum 2, i.e. coaxially with cam 1, and is spring-loaded relative to the machine frame 7 by means of a tension spring 8. The end of shifting lever 5 is supported against the armature of an electromagnet 9, which is stationarily arranged on machine frame 7. The operation of the said electromagnet 9 is controlled by a micro computer 10, which controls also the other operation steps of the machine, and which is connected to electromagnet 9 by means of a line 11. A follower lever 12, which is connected by means of a further known, not represented mechanical transmission to stitch and guard cams 1 3 for the needles, bears against the cam 1.

The device specified above operates as follows: According to the program, pulses are emitted from the micro computer 10 to the electromagnet 9, of which the armature projects, thus swinging the shifting lever 5, while pawl 4 is in engagement with ratchet wheel 3. The back movement of shifting lever 5 and the armature of electromagnet 9 is performed by means of spring 8. Together with ratchet wheel 3, cam 1 also performs a rotary motion and acts continuously upon sensing lever 12, which transmits the motion to the cams 13, whereupon the length of stitches is gradually changed.

By using a further ratchet wheel and a further electromagnet, by which the cam is rotated in the opposite direction, an opposite effect can be also obtained, i.e. the device permits both increasing and reducing the length of stitches. The main advantage of the present invention consists in its simplicity and the possibility of changing arbitrarily the course of stitch length change by means of changing the micro computer pulses, irrespectively of the revolutions and the position of the needle cylinder, while the mounting of the shifting lever makes it possible to use the small force of the electromagnet for shifting.

1. A device for controlling stitch length in circular knitting machines for manufacturing hosiery and similar goods, comprising an adjusting cam and a shifting mechanism, comprising a ratchet-pawl mechanism, associated therewith, wherein the shifting lever of the pawl is directly under pressure of a movable armature of an electromagnet, which is controlled from a micro computer of the machine.

2. A device as claimed in Claim 1 , wherein the shifting lever is mounted coaxially with the ratchet wheel and/or graduation cam and the armature of the electromagnet bears against the end of the shifting lever.

3. A device for controlling stitch length in circular knitting machines for manufacturing hosiery and similar goods, substantially as hereinbefore described with reference to the acompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Device for controlling stitch length in circular knitting machines The present invention relates to a device for controlling stitch length in a circular knitting machine for manufacturing hosiery and similar goods, said device comprising an adjusting cam and a shifting mechanism, comprising a ratchet and pawl mechanism, associated therewith. Devices for controlling stitch length in small diameter, particularly single cylinder knitting machines are known, which use a mechanical drive of the pawl with a constant or adjustable step about one or more ratchet teeth, the latter being coupled with a cam or another tracing device, from which the stitch length is adjusted. Furthermore, a device is known, which uses a stepping position motor, which substitutes, on the basis of pulses from a program controlled electronically by a micro computer, the power element ratchet-pawl, and the pivot motion of which is transferred to a lever, or the needle cylinder of the machine. However, this device is complicated and unreliable. The purpose of the present invention consists in removing the above mentioned disadvantage for machines provided with micro computers for controlling the machine operation, this being substantially achieved by arranging that the shifting lever of the pawl is directly acted upon by a movable armature of an electromagnet, which is controlled by the micro computer of the machine. An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawing, which represents the whole diagram of controlling from a micro computer to stitch and guard cams. A single cylinder circular knitting machine for manufacturing hosiery and similar goods is provided with an adjusting cam 1 mounted rotatably on the surface of the control drum 2, besides further known, not represented, stationarily arranged force operational segments. A ratchet wheel 3 is connected to cam 1, and is engaged by pawl 4, which is swingably mounted on shifting lever 5. Pawl 4 is spring-loaded relative to shifting lever 5 by means of a tension spring 6. The shifting lever 5 is mounted swingably on shaft 21 of control drum 2, i.e. coaxially with cam 1, and is spring-loaded relative to the machine frame 7 by means of a tension spring 8. The end of shifting lever 5 is supported against the armature of an electromagnet 9, which is stationarily arranged on machine frame 7. The operation of the said electromagnet 9 is controlled by a micro computer 10, which controls also the other operation steps of the machine, and which is connected to electromagnet 9 by means of a line 11. A follower lever 12, which is connected by means of a further known, not represented mechanical transmission to stitch and guard cams 1 3 for the needles, bears against the cam 1. The device specified above operates as follows: According to the program, pulses are emitted from the micro computer 10 to the electromagnet 9, of which the armature projects, thus swinging the shifting lever 5, while pawl 4 is in engagement with ratchet wheel 3. The back movement of shifting lever 5 and the armature of electromagnet 9 is performed by means of spring 8. Together with ratchet wheel 3, cam 1 also performs a rotary motion and acts continuously upon sensing lever 12, which transmits the motion to the cams 13, whereupon the length of stitches is gradually changed. By using a further ratchet wheel and a further electromagnet, by which the cam is rotated in the opposite direction, an opposite effect can be also obtained, i.e. the device permits both increasing and reducing the length of stitches. The main advantage of the present invention consists in its simplicity and the possibility of changing arbitrarily the course of stitch length change by means of changing the micro computer pulses, irrespectively of the revolutions and the position of the needle cylinder, while the mounting of the shifting lever makes it possible to use the small force of the electromagnet for shifting. CLAIMS