US3500664A

US3500664A - Fabric draw-off mechanism

Info

Publication number: US3500664A
Application number: US633736A
Authority: US
Inventors: Roland Peberdy
Original assignee: Bentley Engineering Co Ltd
Current assignee: Bentley Engineering Co Ltd
Priority date: 1966-04-30
Filing date: 1967-04-26
Publication date: 1970-03-17
Anticipated expiration: 1987-03-17
Also published as: GB1179554A

Description

March 17, 1970 PEBERDY 3,500,664

FABRIC DRAW-OFF MECHANISM I Filed April 26, 1967 2 Sheets-Sheet 1 March 17, 1970 R. PEBERDY FABRIC DRAW-OFF. MECHANISM 2 Sheets-Sheet 2 Filed April 26. 1967 United States Patent 3,500,664 FABRIC DRAW-OFF MECHANISM Roland Peberdy, Leicester, England, assignor to The Bentley Engineering Company Limited, Leicester, England Filed Apr. 26, 1967, Ser. No. 633,736 Claims priority, application Great Britain, Apr. 30, 1966, 19,093/ 66 Int. Cl. D04b 27/14 U.S. Cl. 66-150 8 Claims ABSTRACT OF THE DISCLOSURE Fabric tensioning means in 'a circular knitting machine having a succession of tensioning members formed by wheels arranged in a circular row above and around the throat of a needle cylinder, the wheels being of toothed form and engaging in the helical thread of a common central worm so that relative rotation between the needle cylinder and the worm causes the tensioning wheels to be rotated and by engagement with fabric close to the needles draws the fabric away from the needles. To avoid reverse turning movement of the tensioning wheels during a reverse swing in reciprocatory knitting, ratchet means is provided to eliminate relative turning movement between the needle cylinder and the worm during such reverse swing.

This invention relates to mechanism for drawing otr fabric from circular knitting machines and is particularly suitable for machines adapted to knit articles, such as socks or stockings, separately and shed individual articles from the needles as they are completed.

In accordance with the invention there is provided in a circular knitting machine, fabric tensioning means comprising a succession of tensioning members positioned within and around the needle circle and having fabric engaging exteriors which are caused to bear downwardly against fabric as it is produced and to move around closed paths in such directions and in such manner as to draw the fabric inwardly from the needles at a desired tension. Conveniently the tensioning members are spaced apart in a circular row around the axis of the needle cylinder or cylinders and positioned immediately above the cylinder throat of a single cylinder machine or the throat of the bottom cylinder of a double cylinder machine. They may be urged resiliently individually towards such throat so as to press against fabric resting thereon. The tension members may be operated by a common drive means positioned within the needle circle.

In a convenient construction the tensioning members are constituted by rotatable wheels. Such wheels may be toothed wheels arranged around and engaging a common driving worm. In rotating cylinder machines such a driving worm is fixed during knitting and the toothed wheels rotate bodily around it together with the needles, the sinkers, etc. and the fabric, and so are rotated about their own axes to draw off the fabric. In rotating cam box machines such a driving worm will rotate with the cam box during knitting and so will rotate the toothed wheels, about their axes, the mountings of the toothed wheels being stationary in relation to the machine as a whole. In either case, the driving worm or its supporting means should be fitted with ratchet means so arranged that when knitting by reciprocation is performed, there is no relative turning movement between the driving worm and the toothed wheels engaging with it and therefore no turning of the toothed wheels when the relative turning movement between the needle cylinder and the cam box is 3,500,664 Patented Mar. 17, 1970 in the opopsite direction to that of normal continuous rotary knitting.

The tensioning members are preferably individually adjustable as to the pressure with which they are urged into engagement with the fabric.

The invention further provides in a circular knitting machine fabric tensioning means as aforementioned assembled as a unit of substantially cylindrical over-all form locatable axially within the upper needle cylinder of a double cylinder machine. The unit may incorporate the tensioning members and carriers thereforepermitting individual operative movement of the tensioning members. Means may be provided for adjustment of pressure applied resiliently to the tensioning members which means may be adapted for actuation form above for example through the upper cylinder cover plate of a double cylinder machine or through a cylinder cap of a single cylinder machine.

The tensioning members are desirably positioned in close proximity to the sinkers of the machine so as to be capable of drawing off fabric as soon as the first few courses are knitted when setting up the fabric on the needles.

The invention is illustrated by way of example in the accompanying drawings showing mechanism according to the invention applied to a double cylinder circular knitting machine. In the drawings:

FIGURE 1 is a part-section view in elevation of the knitting head assembly omitting certain parts particularly in the lower cylinder which have no direct relation to the mechanism of this invention;

FIGURE 2 is a cross-sectional plan view taken on the line II-II in FIGURE 1; and

FIGURE 3 is a cross-sectional plan view taken on the line IIIIIIIIIIII in FIGURE 1.

Mechanism in accordance with the invention is shown in FIGURE 1 mounted inside an upper needle cylinder 1 of a double cylinder circular knitting machine of the rotary cylinder type. Other parts of the machine comprise the lower needle cylinder 2, upper and

lower cam boxes

3 and 4, needle cams S and 6, needle sliders 7 and 8, needles 9 an intermediate plate 10, hearing housing 11, drive gear 12, a thrust race 14 and top bed plate 15. The machine has inside sinkers 49 controlled by sinker cams such as 50, the top surface of which is slightly hollowed for cooperation with fabric engaging and tensioning members about to be described.

With particular reference to FIGURE 1, mechanism for drawing off fabric from the needles as it is produced comprises a number of fabric engaging and tensioning members formed by toothed wheels 18 all engaging a common driving worm 38 secured to a tube 37 which is fixed axially in the machine and prevented from rotating during knitting. The teeth of the wheels 18 provide fabric engaging exteriors which move around closed circular paths when the wheels rotate.

Each toothed wheel 18 is mounted so that its general plane extends radially of the axis of the needle cylinders (see FIGURE 3), being carried on a spindle 19 between the forked ends 20a of a plunger 20. The forked ends 20a have slanted end faces (as seen in FIG. 1) to lie substantially parallel to the bottom cylinder throat to facilitate the passage of knitted fabric below them. Each plunger 20 has a shank 200 which is slidable in the bore of an adjustment member 22. The adjustment member 22 is screw threaded in a sleeve 17 and rotatable by a screwdriver (which may be applied through a hole. 131: in the top cylinder cover plate 13) engaging a slot 22a in the top of member 22. A spring 23 surrounds the shank 20c of the plunger 20 abutting the end of the adjustment member 22 and urging the plunger 20 and thus the asociated wheel 18 into engagement with the knitted fabric.

The toothed wheels 18 and the associated adjustment levices just described are mounted on a cylindrical block 16 having tricks for verge elements 24 and an annular groove for butts 24a of the verge elements 24. To the )lock 16 is secured a plate ring 21 which projects from he block 16 and so provides a stop for the plunger 20. iotation of the plungers on their own axes is prerented by flats 20b engaging with the ring 21. The block L6 is bolted onto a flanged collar. 26 which is locked my means of a pin 27 onto a tube 25. The tube sur- 'ounds and is rotatable with respect to the aforesaid tube l7. The tube 25 is supported at its upper part by a spring 59 through the medium of a drive block and in turn .upports the tube 37 through a collar 39 secured to he tube 37. A spring 41 fills the space between the drivng worm 38 and the bottom of the tube 25 so as to allow he block 16 and the verge elements 24 to be lowered without locking the wheels 18 between the drive worm l8 and sinker earns 50. A control member 51 is fixed to he bottom of the drive worm 38.

The upper end of the tube 25 is slidable in a bush 28 secured by screws 34 to the cover plate 13. The bush B8 is forked at 284 (FIGURE 2) and in the forks are adjustment screws 33, bearing on a lug 30a on the drive )lock 30. Both the adjustment screws 33 are adjusted to nove the lug 3011 between the forks 28a for the circumv 18 do not turn and so do not tend to push the fabric back towards the needles during such reverse stroke.

It will be evident that other fabric tensioning members, such as plain rollers, rotary brushes, or endless bands or chains running round pairs of rollers or sprockets of small diameter one of each pair of which is driven, may be employed in place of the toothed wheels 18.

What I claim is:

1. In a circular knitting machine having a needle cylinder, fabric tensioning means comprising, in combination, tensioning members constituted by rotatable wheels mounted in succession within and around the needle circle, said tensioning members having fabric engaging exteriors and including means permitting said exteriors to move around closed paths in upstanding planes extendindividual to each tensioning member for operating said tensioning members individually to apply tension to the fabric as it is produced.

ferential adjustment of the tube 25 and (through the Block 16) of the verge'elements 24 in order to position hem accurately between the needles. The tube 25 has 1 drive key 32 coupling it to the drive block 30 which is also secured to the tube 25 by screws 31. The spring 29 nests in a recess in the bush 28. Above the drive block 2. A combination according to claim 1 wherein the mounting means carries the tensioning members spaced apart in said needle circle around the axis of the needle cylinder.

3. A combination according to claim 1 wherein said operating means urges the tensioning members resiliently and inwardly towards the throat of the needle cylinder so as to press against fabric resting on said throat.

4. A combination according to claim 1 having a common drive means positioned within the needle circle for operating all of the tensioning members.

5. A combination according to claim 1 wherein the tensioning members are toothed wheels, and wherein there is provided a common driving worm within the wheels for rotating them.

collar 39 is a cover plate secured to the bottom of the circular block 42 which is clamped to the tube 37 by a clamping screw and nut 43. The block 42 has a flange 42g and a spigot 42b which engage a ratchet plate 44, best illustrated in FIGURE 2, secured to a post 46 mounted on a platform 47. The ratchet plate 44 is provided with a notch 44a (FIGURE 2) and the spigot 42b has a spring loaded plunger 48 of square cross section, one end of which is in contact with the bore of the ratchet plate 44. The notch 44a is cut in such a manner as to engage the plunger 48 and prevent rotation of the block 42 and thus of the tube 37 anti-clockwise in FIGURE 2 but not clockwise.

During knitting the tube 37 and thus the drive worm 38. are held stationary and the toothed wheels 18 rotate bodily around it together with the needles 9, the sinkers 49 etc. and the fabric. Thus the toothed wheels 18 are rotated anti-clockwise in the aspect of the wheel seen in FIGURE 1 and draw the fabric as it is produced away from the needles 9 in towards the centre of the lower needle cylinder 2. When the needle cylinders have a to and fro turning movement for performing knitting by reciprocation, the worm 38 is carried around with the remainder of the mechanism in the reverse stroke (i.e. the stroke in the direction opposite to that of normal continuous rotary knitting) being driven by 'bodily revolving m m t 9 w lled h els 18 a d so he o h w el 6. A combination according to claim 5 having associated with the driving worm ratchet means organised to permit relative turning movement between the driving worm and toothed wheels driven thereby only in the direction of normal continuous rotary knitting.

7. A combination according to claim 1 having means forindividually adjusting the pressure of said tensioningmembers.

8.; A combination according to claim 1 having the fabric tensioning mechanism constructed as a unit of substantially cylindrical overall form having a diameter less than the internal'diameter of the needle cylinder.

References Cited UNITED STATES PATENTS 3,380,266 4/1968 Williamson et al 6615O 1,641,101 8/1927 Scott 66l49 XR 2,017,082 10/1935 Warren 66-153 2,137,362 11/1938 Smith et a1. 66--149 XR 2,696,252 12/1954 Rosen 66--153 XR 3,003,342 10/1961 Kent et a1. 66-150 FOREIGN PATENTS 3 1/1890 Great Britain. 223,282 11/ 1942 Switzerland.

WM. CARTER REYNOLDS, Primary Examiner US- C ,R. 6- 53