US2756574A

US2756574A - Cam system of knitting machines

Info

Publication number: US2756574A
Application number: US337171A
Authority: US
Inventors: Shortland Arthur
Original assignee: Mellor Bromley and Co Ltd
Current assignee: Mellor Bromley and Co Ltd
Priority date: 1952-02-15
Filing date: 1953-02-16
Publication date: 1956-07-31
Anticipated expiration: 1973-07-31

Description

y 1956 A. SHORTLAND 2,756,574

CAM SYSTEM OF KNITTING MACHINES Filed Feb. 16, 1953 2 Sheets-Sheet 1 m 15 32- if a a a U 39 i 12 Inventor July 31, 1956 SHORTLAND 2,756,574

CAM SYSTEM OF KNITTING MACHINES Filed Fe 1953 2 Sheets-Sheet 2 Inventor United States Patent CAM SYSTEM OF KNITTING MACHINES Arthur Shortland, Leicester, England, assignor to Melior Bromley & Co. Limited, Leicester, Engiand, a British company Application February 16, 1953, Serial No. 337,171

Claims priority, application Great Britain February 15, 1952 4 Claims. (CI. 66-25) This invention has reference to dial cam systems of knitting machines of the cylinder and dial type which are designed to provide cam races to receive operating butts on the dial needles, or on associated needle-actuating jacks, the said systems being thereby adapted for the control and operation of the needles during knitting.

The stitch cams incorporated in these systems have heretofore usually been made adjustable for the purpose of regulation of the length of loops or stitches, for example to produce knitted fabric of a required quality or/ and as may be required according to the count of the yarn to be used. Now wherever an adjustable dial stitch cam has previously been incorporated in a cam race, a space has been provided in the system to permit of freedom of movement of the said cam, and this space has resulted in a break or gap in the race. Accordingly, it has not heretofore been possible to present to the edges of the butts of the dial needles, or of the needle-actuating jacks, a smooth unbroken cam edge or Wall in the vicinity of a stitch cam. As a consequence, whilst some of the dial needles in the dial have, during retraction hugged the cams and accurately followed the required track from, say, clearing level or height to the knocking-over point at the or each knitting location other needles have tended, where the break or gap in the race occurs, to advance slightly, i. e. move to a small extent outwards before being finally retracted by the dial stitch cam to the knocking-over point. This tendency depends to some extent on the varying thicknesses of the needles and hence the varying degrees of freedom with which they have been capable of moving in their tricks in the needle dial. In short, the needles in a dial have not all followed the same line or wave, and this has given rise to faults in knittingsuch as undesired variations in lengths of loops. In fact, the proper functioning of needles has been noticeably interfered with in the vicinity of an adjustable stitch cam which has heretofore tended to cause marked deformation of the needle line or wave.

The object of the present invention, then, is to provide, in knitting machine of the cylinder and dial type, improvements in the dial cam system thereof designed to overcome the foregoing disadvantages.

According to this invention, there is provided in a machine of this type, a dial cam plate, a backing plate which is pivotally mounted beneath the said dial cam plate for adjustment arcuately, relatively thereto, two one-piece cam parts which are secured to the underside of the backing plate, opposed profiled edges of these parts being spaced apart to provide between them a complete section of a dial cam race, the inner edge of the outer one of these two cam parts being continuous throughout and so profiled as to provide first a guard cam, then a stitch drawing cam portion and finally an adjoining knocking-over cam portion, whilst the outer profiled edge of the inner one of the two cam parts provides first a cam portion for advancing dial needles to tucking level, then a recess opposing the first mentioned guard cam and next a guard cam portion opposing the stitch drawing and knocking-over cam portions, and a clearing cam which is pivotally mounted in the aforesaid recess and is movable from tucking position to clearing position, and vice versa.

Thus, the outer edge or Wall of that section of a dial can-1 race defining stitch drawing and knocking-over cams at a knitting location is made continuous, i. e. unbroken, right from clearing level to the knocking-over point. In other words, the said edge or wall extends uninterruptedly, that is to say, without any detrimental breaks or gaps. Knitting instruments having butts running in such a cam race section are, therefore, caused to move in a smoothly flowing line, wave or coursewithout any abrupt changes in the longitudinal positions thereof. The inner edge or wall of the said cam race sections is defined by a clearing cam arranged in advance of the stitch drawing cam, and guard cam means opposing the stitch drawing and the knocking-over cams.

The stitch drawing and knocking-over cams may be so integrally combined as to constitute adjoining portions of a one-piece cam part which latter is mounted in any suitable manner upon or within a dial cam plate or cap.

It is, of course, important that the ends of the arcuately adjustable cam race section shall properly register or mate up with adjoining portions of the cam race after an adjustment of the backing plate. Conveniently for this purpose, the appropriate end, or each end, of the displaceable section of the cam race, according to requirements, may be increased in width somewhat.

The backing plate and the clearing cam may conveniently be independently adjustable about a common axis coincident, or substantially so, with tucking level or height.

In order that the invention may be more clearly understood and readily carried into practical effect, a specific example of the invention as applied to the dial cam system of a multi-feeder rotary cylinder and dial knitting machine of the interlock type will now be described with reference to the accompanying drawings, wherein,

Figure 1 is an underside plan view of a complete section of the dial cam plate or cap of the machine showing cam parts providing unbroken, i. e. continuous, portions of inner and outer cam races at two circumferentially spaced knitting locations,

Figure 2 is a detail view illustrating a modification of the arrangement shown in Figure 1,

Figure 3 is a cross-section taken on the line 111-111 of Figure 1,

Figure 4 is a plan View of the same section of the dial cam plate or cap, and

Figure 5 is a fragmentary edge view of the said dial cam plate section illustrating screw means employed for adjusting the backing plate.

Like parts are designated by similar reference characters throughout the drawings.

The interlock machine to which the examples are applied, includes a set of short dial needles such as 1 (Figure 3) having operating butts 2 arranged to run in an outer cam race A in the dial cam plate or cap 3, and a second set of long dial needles 4 furnished with butts 5 arranged to run in an inner cam race B in the said plate or cap. Cooperating with the short and long dial needles are a set of long cylinder needles such as 6 (Figure 7) having operating butts 7 arranged to run in a lower cam race C in the cylinder cam box 8 and a set of short cylinder needles (not shown) provided with butts running in an upper cam race D in this box. The knitting locations K in the dial cam system are so arranged in staggered relation as to occur alternately in the races A and B; similarly, the knitting locations K in the cylinder cam system occur alternately in the races C and D. This arrangement of double cam systems is common to all interlock machines and, as well known to those acquainted with the art, a socalled interlock fabric produced on such a machine comprises two webs (usually knitted on a 1 x 1 basis) connected by crossed sinker wales.

In accordance with usual practice, moreover, the dial cam plate or cap 3 is made up of a plurality of adjoining and similar segmental sections E a complete one of which is shown in Figures 1 and 4. There are two of the knitting locations K to each section Eone in the race A and the other in the race 13. In much the same way, the cylinder cam box 8 is made up of a plurality of adjoining and similar arcuate sections F of which one is shown in Figure 6. To each cam box section F there are two of the knitting locations K one in the race C and the other in the race D.

According to the present invention there is provided heneath each dial cam plate section E, at each of the two relevant knitting locations K, a backing plate 9 the in ner and outer

longitudinal edges

10 and 11 of which are straight and parallel whereas the opposite ends 12. and 13 thereof are straight, relatively inclined and non-radial with respect to the central axis of the machine. Secured, e. g. by screws, to the underside of the backing plate 9, are two one-

piece cam parts

14 and 15, the opposed appropriately profiled edges 14a and 15a of which are suitably spaced apart to provide between them a complete section A or B of the relevant dial cam race all as depicted in Figure 1. The inner edge 14a of the outer one 14- of these two cam parts constitutes the outer wall of the relevant cam race section and is continuous throughout, being so pro-filed as to provide, in order from the leading end of the cam, first a guard cam portion 16 opposing a clearing cam 17 hereinafter to be described, then a stitch drawing cam portion 18 and finally an adjoining knocking-over cam portion 19. The outer profiled edge 15a of the inner one 15 of the said two cam parts constitutes, on the other hand, the inner wall of the appropriate cam race section, and provides first a cam portion 20 for advancing dial needles to tucking level T, then a triangularly shaped recess 21 to receive the clearing cam 17, and a guard cam portion 22 opposing the aforesaid stitch drawmg and knocking-over

cam portions

18 and 19. Integral with and projecting vertically upwards from the top side of the backing plate 9, near to its leading end (i. e. the end thereof facing oncoming dial needle operating butts), is a hollow cylindrical stem 23 (see Figure 3) mounted to turn in a bearing 24 formed in the dial cam plate or cap 3. The upper end of this stern projects above the top surface of the dial cam plate or cap 3 and has rigidly secured thereto a setting plate 25 adapted to facilitate the Setting of the corresponding clearing cam 17 either in its clearing position, such as that indicated at the right-hand side of Figure 1, or in its tucking position shown at the left-hand of this figure. Each of the clearing cams 17 is of triangular form and is secured beneath, or is integral with, a disc 26 mounted to turn within a circular bearing recess formed in the underside of the adjustable backing plate 9. Co-axial with, and extending vertically upwards from, the disc 26 is an axle 27 which takes a bearing and 1S turnable within the hollow cylindrical stem 23 on the backing plate. At its upper end the axle 27 projects up beyond the corresponding end of the concentrically disposed cylindrical stem 23 and has rigidly secured thereto a lever 23 which at its outer end is fitted with a screw 29 having a knurled head 30. The lower end of the screw 29 is screwed into one or the other of two tapped holes 31 formed in the outer end of the setting plate 25. The idea is that by turning the screw 29 anti-clockwise it can be withdrawn from either of the tapped holes 31 to free the lever 28 and thereby enable the latter to be turned to its alternative position. When so turned the lever 28 can be locked in its new position, relatively to the backing plate 9, by turning the screw 29 clockwise so that it will engage in the relevant tapped hole 31. Each clearing cam 17 is, therefore, of the swing type and is located within the relevant cam race section, being movable from one position in which it is wholly located within the corresponding triangularly shaped recess 21 to permit the dial needles of the appropriate set to pass the yarn feeding point at tucking level T to another position in which it serves to advance these dial needles to clearing level. Each backing plate 9 and the

cam parts

14 and 15 attached thereto are accordingly adjustable en bloc, and whenever a backing plate is adjusted, the corresponding setting plate 25 and the superimposed lever 28, locked together by the associated screw 29, will both turn together about the axis a. It will, however, be appreciated that the clearing cam 17 be adjusted independently of the backing plate 9 about the same axis a which latter is substantially coincident with tucking level T.

To enable it to be pivotally adjusted, each backing plate 9 is provided with a vertically disposed peg 32 which projects up through a circular hole 33 formed in the dial earn plate or cap 3. The diameter of the hole 33 exceeds that of the peg 32, thereby permitting the latter a certain limited degree of movement within the hole upon adjustment of the backing plate. A compression spring 34, accommodated in a horizontally disposed hole 35 formed in the dial cam plate or cap, is arranged to impinge on the inner side of the peg 32. For action on the other side of the said peg there is provided an adjusting screw 36 the partially screwed shank of which extends through a partially tapped hole in the dial cam plate or cam and into the circular hole 33. As shown in Figures 1 and 5, the head 36a of the screw 36 is accommodated in a counterbore 37 formed in the outer edge of the dial cam plate or cap. This head 36a has formed therein a screw-driver slot and is peripherally toothed for engagement with a spring detent 38.

The leading end or" each displaceable cam race section A or B is, in this example, flared at 39 (see Figure 1) and thereby increased in width so that, notwithstanding an arcuate adjustment of the relevant backing plate 9 and

cam parts

14 and 15 en bloc, the displaced race section will still properly register with the adjoining run portion A or B of the cam race.

It will be noted that in Figure 1, each of the two pivoted clearing carns 17 is pivoted at a at the righthand side of the triangularly shaped recess 21 (as viewed in the figure). This arrangement, although generally satisfactory, may tend to upset the form of the cam race section when the clearing cam is raised to clearing height. Should any difliculty arise on this account, it may be obviated by slightly varying the shape of the recess 21 and pivoting the cam at the opposite side of the latter as depicted in Figure 2.

I claim:

1. In a circular knitting machine of the cylinder and dial type, a dial cam plate, a backing plate which is pivotally mounted beneath the said dial cam plate for adjustment arcuately, relatively thereto, two one-piece cam parts which are secured to the underside of the backing plate, opposed profiled edges of these parts being spaced apart to provide between them a complete section of a dial cam race, the inner edge of the outer one of these two cam parts being continuous throughout and so profiled as to provide first a guard cam, then a stitch drawing cam portion and finally an adjoining knockingover cam portion, whilst the outer profiled edge of the inner one of the two cam parts provides first a cam portion for advancing dial needles to tucking level, then a recess opposing the first mentioned guard cam and next a guard cam portion opposing the stitch drawing and knocking-over cam portions, and a clearing cam which is pivotally mounted in the aforesaid recess and is movable from tucking position to clearing position, and vice versa.

2. In a circular knitting machine of the cylinder and dial type, a dial cam plate having an opening therein, a backing plate which is pivotally mounted beneath the said dial cam plate for adjustment arcuately, relatively thereto, two one-piece cam parts which are secured to the underside of the backing plate, opposed profiled edges of these parts being spaced apart to provide between them a complete section of a dial cam race, the inner edge of the outer one of these two cam parts being continuous throughout and so profiled as to provide first a guard cam, then a stitch drawing cam portion and finally an adjoining knocking-over cam portion, whilst the outer profiled edges of the inner one of the two cam parts provides first a cam portion for advancing dial needles to tucking level, then a recess opposing the first mentioned guard cam and next a guard cam portion opposing the stitch drawing and knocking-over cam portions, a clearing cam which is pivotally mounted in the aforesaid recess and is movable from tucking position to clearing position, and vice versa, a peg on the backing plate which projects through the opening in the dial cam plate, and, mounted in the latter, an adjusting screw for action upon said peg for the purpose of adjusting the backing plate.

3. In a circular knitting machine of the cylinder and dial type, a dial cam plate having therein a bearing, a backing plate which is pivotally mounted beneath the said dial cam plate for adjustment arcuately, relatively thereto, said backing plate having therein a bearing recess coaxial with the bearing in the dial cam plate, two one-piece cam parts which are secured to the underside of the backing plate, opposed profiled edges of these parts being spaced apart to provide between them a complete section of a dial cam race, the inner edge of the outer one of these two cam parts being continuous throughout and so profiled as to provide first a guard cam, then a stitch drawing cam portion and finally an adjoining knocking-over cam portion, whilst the outer profiled edge of the inner one of the two cam parts provides first a cam portion for advancing dial needles to tucking level, then a recess opposing the first mentioned guard cam and next a guard cam portion opposing the stitch drawing and knockingover cam portions, a hollow cylindrical stem which extends upwards from the backing plate and is mounted to turn in the bearing in the dial cam plate, the upper end of the said stem projecting above the dial cam plate, a clearing cam which is pivotally mounted in the recess opposing the first mentioned guard cam and is movable from tucking position to clearing position, and vice versa,

4 a disc which carries the cleanng cam and 1s mounted to turn within a bearing recess in the backing plate, an axle on said disc which extends up through, projects from and is turnable within the hollow cylindrical stem, a plate which has holes therein and is secured to the upper projecting end of the said hollow stem, and, secured to the upper projecting end of the axle, a lever furnished with means for engagement with a selected hole in the said plate for the purpose of setting the clearing cam.

4. In a circular knitting machine of the cylinder and dial type, a dial cam plate, a backing plate which is pivotally mounted beneath the said dial cam plate for adjustment arcuately, relatively thereto, two one-piece cam parts which are secured to the underside of the backing plate, opposed profiled edges of these parts being spaced apart to provide between them a complete section of a dial cam race, the inner edge of the outer one of these two cam parts being continuous throughout and so profiled as to provide first a guard cam, then a stitch drawing cam portion and finally an adjoining knocking-over cam portion, whilst the outer profiled edge of the inner one of the two cam parts provides first a cam portion for advancing dial needles to tucking level, then a recess opposing the first mentioned guard cam and next a guard cam portion opposing the stitch drawing and knockingover cam portions, and a clearing cam which is pivotally mounted in the aforesaid recess and is movable from tucking position to clearing position, and vice versa, said clearing cam and the backing plate being independently adjustable about a common axis coincident with tucking level.

References Cited in the file of this patent UNITED STATES PATENTS 539,837 Townsend May 28, 1895 1,056,691 Kimes Mar. 18, 1913 1,220,918 Wilcomb Mar. 27, 1917 1,424,725 Howie et a1. Aug. 1, 1922 2,091,638 Jacques et a1. Aug. 31, 1937 2,199,637 Lawson May 7, 1940 2,475,170 Zieve July 5, 1949 2,495,872 Stibbe et a1. Jan. 31, 1950 FOREIGN PATENTS 171,591 Great Britain Nov. 24, 1921 258,940 Italy June 5, 1928