GB2156866A

GB2156866A - Control device of stitch length and yarn guide means for circular knitting machines

Info

Publication number: GB2156866A
Application number: GB08508200A
Authority: GB
Inventors: Masatoshi Sawazaki
Original assignee: Precision Fukuhara Works Ltd
Current assignee: Precision Fukuhara Works Ltd
Priority date: 1984-03-29
Filing date: 1985-03-29
Publication date: 1985-10-16
Also published as: GB8508200D0; JPS60209056A; KR860000954B1; DE3510500A1; IT1181857B; JPS6331578B2; IT8547842A1; ES542330A0; IT8547842A0; KR850006714A; ES8605063A1

Abstract

A control device is provided for simultaneously varying the length of stitch loops and the positioning of the yarn guides 28 in a multifeed circular knitting machine. The device includes a vertically adjustable inner cam ring 6 which supports the needle control cams 7 and the yarn guides 28 in fixed positions thereon. A rotatable adjusting ring 18 surrounds the inner cam ring 6 and is threadably connected thereto so that rotation of the adjusting ring imparts vertical movement to the inner cam ring. A manually rotatable small adjusting gear imparts rotation to the adjusting ring 18 to raise or lower the inner cam ring 6 and vary the length of the stitch loops being formed while the yarn guides 28 are automatically maintained in the same feeding relationship with the hooks of the upper ends of the needles 3 at each of the yarn feeding and knitting stations. <IMAGE>

Description

SPECIFICATION Control device of stitch amount and yarn guide means for circular knitting machines This invention relates generally to a central control device for simultaneously varying the length of stitch loops and the positioning of the yarn guide means in a multifeed circular knitting machine, and more particularly to such a central control device in which the needle cams and yarn guides at each knitting station are supported on an inner cam ring which is vertically adjustable relative to the needle cylinder to vary the length of the stitch loops being formed and while maintaining the yarn guides in the same yarn feeding relationship with the hooks on the upper ends of the needles.

It is the usual practice to change the length of stitch loops being formed on a multifeed circular knitting machine by vertically adjusting the individual stitch cams at each of the yarn feeding and knitting stations to provide a vertical adjustment of the operating paths of the knitting needles. This also requires that the vertical positions of the yarn guides be adjusted or the knitting needles may engage the yarn guides and cause needle breakage.

Therefore, vertical adjustment of the individual stitch cams at each knitting station must be accompanied by a like vertical adjustment of the individual yarn guides. As will be recognized, the individual adjustment of the stitch cams at each knitting station and the individual adjustment of the yarn guides are time-consuming operations and require an operator skilled in such stitch cam adjustment to ensure that the proper adjustment is made at each of the yarn feeding and knitting stations around the circular knitting machine.

With the foregoing in mind, it is an object of the present invention to provide a control device for simultaneously varying the length of stitch loops and the positioning of the yarn guides which may be operated by a relatively unskilled operator in a very short period of time and wherein the stitch length adjustment at each of the yarn feeding and knitting stations is identical.

In accordance with the present invention, the control device includes an inner cam ring surrounding the needle cylinder and supporting the stitch cams at each of the yarn feeding and knitting stations of the knitting machine. The inner cam ring also supports the yarn guides at each of the yarn feeding and knitting stations. The inner cam ring is supported for vertical adjustment on a fixed base of the machine so that vertical adjustment of the inner cam ring imparts a corresponding amount of vertical adjustment to the stitch cams and to the yarn guides to thereby vary the length of stitch loops being formed while the yarn guides are automatically maintained in the same yarn feeding relationship with the hooks of the upper ends of the needles.

The vertical adjustment of the inner cam ring relative to the fixed base is accomplished by a threaded connection between the inner cam ring and an adjusting ring which is supported in a fixed vertical position for rotation by an outer cam ring carried by the fixed base. The adjusting ring is rotated by means of a manually rotatable small adjusting gear meshing with teeth on the adjusting ring.

Manual rotation of the small adjusting gear thus imparts rotation to the adjusting ring and imparts simultaneous vertical movement to the inner cam ring and to the stitch cams and yarn guides supported thereby so that simultaneous adjustment is imparted to both the stitch cams and the yarn guides when the inner cam ring is vertically adjusted.

In order that the present invention may be more readily understood, reference will now be made to the accompanying drawings, in which: Figure 1 is a vertical sectional view through the needle cylinder of a knitting machine and illustrating a central or centralised control device according to the invention; Figure 2 is a fragmentary vertical sectional view at an enlarged scale, being taken substantially along the line 2-2 in Fig. 3; and Figure 3 is a fragmentary plan view of the inner cam ring and associated parts.

Referring particularly to Fig. 1, the knitting machine includes a needle cylinder 1 including vertically extending needle grooves or slots 2 formed in the outer peripheral surface thereof and supporting needles, broadly indicated at 3, for vertical movement therein.

Cam holder support brackets 4 extend around the needle cylinder 1 and are fixed to the upper surface of an inner cam ring 6, as by means of screws 5. Needle control cams 7 are supported on the cam holder brackets 4 and are operable on the butts of the knitting needles 3 to control the vertical path of travel of the upper hooked ends of the needles in the formation of stitch loops at each of the yarn feeding and knitting stations.

Sinkers 8 cooperate with the knitting needles 3 during the formation of stitch loops and are supported for radial sliding movement in a sinker dial 9. The radial position of the sinkers 8 is controlled by a sinker cam 11 fixed to a sinker cap 10 which is supported by a sinker cap ring 1 2. A driving gear 1 3 is fixed to the lower surface of the needle cylinder 1 and is driven in the conventional manner to impart rotation to the needle cylinder 1 during the knitting operation.

A base support ring 1 4 supports an outer cam ring 1 6 in a fixed position thereon, as by screws 1 7. The inner cam ring 6 is supported for vertical adjustment on the outer cam ring 1 6 by vertically adjustable means, to be presently described, and rotation of the inner cam ring relative to the outer cam ring 16 is prevented by guide means, illustrated as a guide pin 1 5 fixed at its upper end in the outer cam ring 1 6 and having its lower end slidably received in a corresponding bore in the inner cam ring 6. It is preferred that about six guide pins 1 5 be equally spaced around the circumference of the needle cylinder 1.

The vertically adjustable means supporting the inner cam ring 6 for vertical movement on the outer cam ring 1 6 includes an adjusting ring 1 8 surrounding the outer periphery of the inner cam ring 6 and being connected thereto by a threaded connection, broadly indicated at 1 9. The threaded connection includes external threads 1 9a (Fig. 2) formed on the outer periphery of the inner cam ring 6 and mating internal threads 1 9b formed on the inner peripheral surface of the adjusting ring 18.

The outer peripheral portion of a setting support ring 21 is fixed to the lower portion of the outer cam ring 16, as by screws 22, and the inner peripheral portion of the setting ring 21 slidably supports the lower surface of the adjusting ring 18 thereon. As shown in Fig. 2, the lower end portion of a compression spring 20 is supported in a bore in the inner cam ring 6 and its upper end is supported in a bore in the outer cam ring 1 6 to resiliently maintain the external threads 1 9a and the internal threads 1 9b in resilient engagement with each other when moved to adjusted position, in a manner to be presently described. The springs 20 are also preferably positioned at about six equally spaced locations around the needle cylinder 1.

A small adjusting gear 23 is supported for manual rotation in the outer cam ring 1 6 and is positioned to engage with gear teeth extending around the outer peripheral surface of the adjusting ring 1 8. The small adjusting gear 23 is provided with an integrally formed and upwardly extending shaft portion supported for rotation in a bore in the outer cam ring 1 6 and having an upper end substantially flush with the upper surface of the outer cam ring 1 6. Suitable means for rotating the shaft 24 and the gear 23 is provided and is illustrated in the form of an allen head socket 24a.While only a single small adjusting gear 23 is illustrated, it is to be understood that several small adjusting gears 23 may be positioned at various locations around the knitting machine in convenient locations for manual adjustment by the machine operator.

Thus, the inner cam ring 6 is supported for vertical adjustment, relative to the outer cam ring 16, the fixed base 14, and the needle cylinder 1 by means of the threaded connection 1 9 between the adjusting ring 1 8 and the inner cam ring 6. Manual rotation of the small adjusting gear 23 by the operator imparts rotation to the adjusting ring 1 8 to thereby selectively raise and lower the inner cam ring 6 while the spaced-apart guide pins 1 5 spaced-apart guide pins 1 5 prevent relative rotation between the adjusting ring 1 8 and the inner cam ring 6.

From four to six yarn carrier ring support brackets 25 are spaced around the needle cylinder 1 and have their lower ends fixed on the inner cam ring 6. The upper ends of the yarn carrier ring support brackets 25 are fixed to a yarn carrier ring 26, as by a screw 27.

Yarn guide means, broadly indicated at 28, are spaced around and fixed to the lower surface of the yarn carrier ring 26 with screws 29. The yarn guide means 28 each include a yarn holder bracket 30 and a yarn carrier 31 for guiding the yarn to be knit into the upper hooked ends of the needles 3.

The lower end portions of sinker cap support brackets 32, corresponding in number to the yarn carrier ring support brackets 25, are fixed on the outer cam ring 1 6 and include horizontally extending arm portions extending through cutouts in the yarn carrier ring support brackets 25, as illustrated in Fig. 1. The sinker cap ring 1 2 is fixed to the inner horizontal arm portions of each of the sinker cap ring support brackets 32, as by a screw 33.

Thus, the sinker cap ring 1 2 and the sinkers 8 are supported in a fixed position relative to the needle cylinder 1 when vertical adjustment is imparted to the inner cam ring 6 to vary the vertical position of the path of travel of the knitting needles 3 and the vertical position of the yarn carriers 31.

The central control device of the present invention is arranged so that only the inner cam ring 6 can be vertically moved to adjusted position. Since the cam holder brackets 4 and the associated knitting cams 7, and the yarn carrier ring support brackets 25 and associated yarn carriers 31 are supported by the vertically movable inner cam ring 6, simultaneous adjustment of the length of stitch loops and the positioning of the yarn guides automatically takes place with vertical adjustment of the inner cam ring 6. Vertical adjustment of the inner cam ring 6 is carried out in a simple manner from a single convenient location adjacent the knitting machine by inserting an allen wrench in the socket 24a and manually rotating the small gear 23 to thereby rotate the adjusting ring 1 8 and impart the desired amount of vertical movement to the inner cam ring 6. Since the needle cams 7 and the yarn guides 31 are simultaneously vertically adjusted at each of the yarn feeding and knitting stations, the same amount of stitch length adjustment is provided at each of the yarn feeding and knitting stations around the needle cylinder, and the same relationship is maintained between the yarn guides and the hooks of the needles.

Claims

1. A control device for use upon a multifeed circular knitting machine at each feed of which a yarn guide is adapted to feed a yarn to a circular series of latch needles to form stitches of the yarn on the needles, the machine being of the type in which the length of the stitches formed of the yarn on the needles and the position of the yarn guide relative to the needles are individually adjustable, the device comprising means to simultaneously adjust both the length of the stitches as well as the position of the yarn guide at each feed of the machine, the arrangement being such that the position of the yarn guides relative to the needles automatically remains the same regardless of the length of the stitches being formed on the needles.

2. A control device according to Claim 1 wherein said circular series of latch needles is supported for vertical movement in a needle cylinder, and including needle control cams surrounding said needle cylinder and being operable to raise and lower said needles for forming stitch loops of the yarn fed thereto, a fixed base surrounding and supporting said needle cylinder at a fixed level thereon, an inner cam ring surrounding said needle cylinder and supporting said needle control cams in a fixed position thereon, and yarn guide support means fixed on said inner cam ring and supporting said yarn guides thereon, and wherein said adjusting means supports said inner cam ring for vertical movement relative to said fixed base so that vertical adjustment of said inner cam ring imparts a corresponding amount of vertical adjustment to said needle control cams and to said yarn guides to thereby vary the length of the stitch loops being formed while maintaining said yarn guides in the same yarn feeding relationship with said needles.

3. A control device according to Claim 2 wherein said adjusting means includes an adjusting ring supported for rotation around said inner cam ring, external threads on the outer peripheral surface of said inner cam ring, internal threads on the inner peripheral surface of said adjustment ring and mating with said external threads on said inner cam ring, and means for imparting rotation to said adjustment ring in one direction to vertically raise said inner cam ring and in the opposite direction to vertically lower said inner cam ring.

4. A control device according to Claim 3 wherein said means for imparting rotation to said adjusting ring includes gear teeth formed around the peripheral outer surface of said adjustment ring, a small adjusting gear supported for rotation relative to said fixed base and with the teeth thereof engaging the teeth on the outer peripheral surface of said adjusting ring, and gear rotating shaft means fixed to said small gear and extending outwardly thereof to permit manual rotation of said shaft and said small adjusting gear.

5. A control device according to Claim 3 or 4 including guide pin means extending into said inner cam ring and preventing rotation thereof when said adjusting ring is rotated by said small adjusting gear.

6. A control device for use upon a multifeed circular knitting machine, constructed and adapted to operate substantially as hereinbefore described with reference to the accompanying drawings.