GB2204600A

GB2204600A - Circular knitting machine with multiple number of feeds

Info

Publication number: GB2204600A
Application number: GB08810115A
Authority: GB
Inventors: Yukiari Iida
Original assignee: Precision Fukuhara Works Ltd
Current assignee: Precision Fukuhara Works Ltd
Priority date: 1987-05-07
Filing date: 1988-04-28
Publication date: 1988-11-16
Anticipated expiration: 2008-04-28
Also published as: IT1219932B; ES2007835A6; IT8847903A0; GB8810115D0; DE3814881A1; JP2628162B2; JPS63282344A; GB2204600B; DE3814881C2

Description

2 2 9 J1 6 0 0 CIRCULAR KNITTING MACHINE WITH MULTIPLE NUMBER OF FEEDS 1

This invention relates generally to a multiple feed circular knitting machine of the type including selector cams mounted gn rotary cylinders positioned in advance of each of the feeds for selectively positioning needles in one of three positions, knit, tuck and welt positions, and more particularly to such a machine in which the selector cams are positioned at the closest possible lateral distance from each other to permit an increased number of feeds to be positioned around the machine.

It is known to provide a multiple feed circular knitting machine which permits selection of the needles in one of three positions, knit, tuck and welt positions, at each of the feeds and wherein the selector device also operates to prevent movement of the stitch loops upwardly on the needles when forming blister knit types of stitch constructions. In this conventional type of circular knitting machine, it is possible to provide, for example, 48 feeds in a machine having a 30 inch diameter needle cylinder. This known type of selector device is illustrated in Figure 5 with the knitting needles 41 including a master butt 4a'-and having selector butts, as indicated at 4bl, positioned at four different levels below the master butt 4a'. A first row of tuck selector cams is supported on rotatable tuck selector cam cylinders 9' while a second row of knit selector cams is supported in laterally spaced relationship on knit selector cam cylinders 111.

In order to increase productivity of this type of machine, it is desirable to increase the number of feeds surrounding the needle cylinder and, therefore, the distance between individual feeds of the machine must be shortened. The arrangement of the adjacent rows of tuck and knit, selector cams, illustrated in the prior art of Figure 5, makes it practically impossible to narrow the distance L between the centers of the needle controlling cams so thc3t it is not possible to substantially reduce the distance between the individual feeds of the knitting machine.

With the foregoing in mind, it is an object of the present invention to provide a multiple feed circular knitting machine with tuck and knit selector cams arranged at te closest possible lateral distance from each other so that it is possible to provide an increased number of feeds around the machine.

In accordance with the present invention, only two types of knitting needles are required and each type of knitting needle has a master butt adapted to be engaged by stitch cams to draw all of the needles to a stitch forming level immediately following each of the feeds. Each type of knitting needle also includes a single knit selector butt, and a single tuck selector butt.---Two tuck selector cams are positioned Li advance f of the position where the needles are drawn to stitch forming level and the tuck selector cams are aligned to 1 engage the tuck selector butts of each type of needle. Two knit selector cams are aligned to engage the knit selector butts and both the.tuck and knit selector cams are mounted on rotatable cylinders to selectively position the tuck and knit selector cams in operative and inoperative positions. The knit selector cam cylinders are positioned to overlap portions of the knit selector cam cylinders to permit the tuck and knit selector cams to be arranged at the closest possible lateral distance from each other and to thereby permit an increased number of feeds to be positioned around the machine. Preferably, the knit selector cams may be selectively positioned in a knit position, a welt position, and a third position where they operate to prevent upward" movement of the stitch loops, particularly when forming -itch copstructions. Because the pairs of blister type st tuck selector cams and knit selector cams are positioned at the closest possible lateral distance from each other, it is possible,- -to provide a large number of feeds around the knitting machine, on the order of 72 feeds in a knitting machine having a 30 inch diameter needle cylinder.

The invention will now be described by way of example with reference to the accompanying partly diagrammatic drawings, in which:- Figure 1 is a somewhat schematic developed layout view of the dial cams at each of three adjacent feeds and illustrating the two types of dial needles utilized therewith; Figure 2 is a vertical sectional view through the dial, being taken substantially along the line 2-2 in Figure 1; Figure 3 is a fragmentary plan view of the dial cam holder, showing the opposite side from that shown in 0 4 Figure 1; Figure 4 is a-somewhat schematic developed layout view of one feed of the machine and illustrating one of the knit selector cams being positioned to prevent movement of stitches when knitting a blister type stitch construction; and Figure 5 is a developed layout view of the tuck and knit cam selector devices of a conventional prior art type knitting machine.

As illustrated in Figure 1, three adjacent feeds, broadly indicated at 1 through 3, of the dial-of a circular knitting machine are illustrated with the tuck and knit carti selector devices of the present invention associated with each of the feeds 1-3. Two dif- ferent types of dial needles,'broadly indicated at 4, 5, are supported for radial sliding movement in the dial of the knitting machine. These dial needles 4, 5 cooperate with the cylinder needles, not shown, in a conventional manner to form the knit fabric. A dial cam holder 6 supports an outer guard cam 7 and a stitch cam 8 (Figure 1). The dial cam holder 6 also rotatably supports two knit selector cam cylinders, broadly indicated at 9, 10 in Figure 2, and two tuck selector cam cylinders 11, 12. The inner end portions of the cylinders 9, 10 are provided with respective knit selector cams 91, 101 which are aligned with and adapted to engage the respective upper selector butts 4b and 5c of the respective dial needles 4, 5.

As shown in Figure 2, a larger diameter collar 93 extends outwardly beyond the shaft portion 92. This collar 93 is provided with three spaced-apart peripheral notches or slots 94. 95 and 96 (Figure 3). A locking key 131 extends upwardly from a plate member 13 attached along the bottom of a recess 61 of the dial cam holder 1:

1 6. Positioning of the knit selector cam cylinders 9, 10 can be accomplished by engagement with one of the three peripherally spaced slots with the respective locking members 131 and 132.

Tuck selector cams 111 and 121 are formed on the inner ends of corresponding tuck selector cam cylinders 11, 12, and are aligned to engage the corresponding tuck selector butts 4d, 5e on the respective dial needles 4, 5. The knit selector cam cylinder 11 is pro- vided with an enlarged collar 113 (Figure 2) which is spaced from the cylindrical shaft portion 112 and provided with two peripherally spaced locking notches or slots 114 and 115 (Figure 3). The positioning of the cylinder 11 is carried out by meshing one of the slots 114 or 115 with a locking key 141 extending upwardly from plate 14. Selectve positioning of the cylinder 12 is accomplished in the same manner as the cylinder 11 with meshing of a loc king key 142.

As shown in Figure 2, a compression spring 17 surrounds the cylinder 9 and extends between a washer 16 inside of a cover plate 15 and the enlarged collar 93 SO that the cylinder 9, as well as the other cylinders 11-12, ae resiliently urged inwardly to the locked position. In order to change the position of any of the cylinders 9-12, the selected cylinder is moved out- wardly, as illustrated by the cylinders 10 and 12 in Figure 2, so that the same can be rotated and positioned in a new locked position.

The four cam track pathways along which the corresponding tuck and knit selector butts of the dial needles 4, 5 pass are shown in dotted lines indicated at 4B, 5C, 4D, and 5E (Figures 1 and 4). Cam tracks 4A and 5A are followed by the main butts of the dial eedles 4, 5 and are formed by the outer guard cam 7 and the stitch cam 8. Cam tracks 4B and 5C are formed by the knit selector cams 91 and 101. Cam tracks 4D and 5E are formed by the tuck selector cams 111 and 121. The cam tracks for dial knitting needle 4 and the cam tracks for dial knitting needle 5 are basically the same in that each of these cam tracks permits either type of needle to be selectively positioned in one of three positions, knit, tuck and welt positions, at each of the feeds.

Although not necessarily indispensable to the present invention, the machine illustrated in the drawings is equipped with a support function for prevention of the movement of stitches, particularly when forming a blister type stitch construction. This support function is.illustrated in Figure 4 where the butt 5e of knitting needle 5 engages with a tuck selector cam 121 and is moved outwardly to a midway or tuck position along cam track 5E. Iipmediately after moving outwardly to the tuck position, the dial knitting needle 5 is moved inwardly by engement of its knit selector butt 5c by the knit selector cam 101 so that as the cooperating cylinder needle, not shown, has been raised up, the possible upward movement of the stitch loop on the cylinder needle is prevented.

4 With the two tuck selector cams 111 and 121 and the two knit selector cams 91 and 101 positioned as -25 shown in Figure 1, the action of the dial needles 4, 5 will be described as they move from left to right through the three feeds 1-3. At feed 1, the tuck selector butts 4d and 5e engage the respective tuck selector cams 111 and 121 to move the corresponding dial needles 4, 5 outwardly to tuck position along cam tracks 4D and 5E so that the main butts 4a, 5a each move outwardly along guard cam surfaces 71 and 72 and above a guard cam f 74. The knit selector butt 5c of the needle 5 is not raised by the correspond.ing knit selector cam 101 so c I1 I- 1 that its main butt 5a is not moved outwardly and passes above guard cam 75. The knit selector butt 4b of the needle 4 is engaged and moved outwardly by the knit selector cam 91 so that this needle 4 is moved outwardly to a shed position where the stitch loop is positioned inwardly of the tip of the latch thereof. The main butt 4a of the needle 4 then engages and is moved inwardly by inclined portion 76 of the guard cam 7 so that it is drawn back inwardly to a position corresponding with the needle 5. The main butts 4a and 5a of both needles are then moved inwardly by the inwardly inclined portion 81 of the stitch cam 8 and both needles are drawn inwardly to stitch drawing level, above the cam portions 82 and 83 of the stitch cam 8. Thus, at feed 1 the needles 4 knit while the needles 5 tuck, that is, they pick up a yarn in their hooks wihout knitting the same.

As the needles 4,- 5 pass the feed 2, the tuck selector butt 4d engages the tuck selector cam lla to move the needle 4 outwardly to the tuck position. Since the knit selector cam 91 does not engage the butt 4b of the needle 4, this needle 4 remains in the tuck position as it passes the feed 2. The tuck selector cam 121 is in the inoperative position so that the tuck selector butt 5e of needle 5 is not engaged thereby so that the needle 5 passes the feed 2 in a welt or float position without being projected outwardly by either the tuck selector cams or the knit selector cams. Thus, at feed 2, the needles 4 are moved outwardly to tuck position while the needles 5 remain in a welt or float position.

At the next feeding station 3, the knit selec tor butt 4b and the tuck selector butt 4d of the dial needle 4 do not engage the respective knit and tuck selector cams so that these needles do not movc out wardly, as indicated by the dotted line in Figure 1, so that the needles 4 move past the feed 3 in welt or float -a- position. The butt 5e of dial needle 5 engages the tuck cam 121 and is moved outwardly thereby. Then, the knit selector butt 5c engages the knit selector cam 101 so that the needle 5 is moved outwardly to the knit position. Thus, at feed 3 the needles 4 welt or float while the needles 5 knit. While the present invention has been described and illustrated in the operation of dial needles 4, 5, it is to be understood that the present selector system could be provided to control cylinder needles in a similar manner.

In comparison with the conventional type of circular knitting machine in which the needles have only one selector butt at four different levels in addition to the master bult and wherein two rows of four rota- table cylindrical selector cams are used for controlling the positioning of the.needles by t he selector butts, the present invention provides for greatly increasing the number of feeds around the circular knitting machine by using a combinaticnT of two types of knitting needles, each having at least two selective or selector butts at different levels, in addition to a master butt. Also, the present invention provides only two knit selector cam,cylinders and two tuck selector cam cylinders. The two tuck selector cam cylinders are positioned to overlap portions of the two knit selector cam cylinders to permit the tuck and knit selector cams to be arranged at the closest possible lateral distance from each other. This close positioning of the tuck and knit selector cams thereby permits an increased number of feeds to be positioned around the machine. For example, with the selector cam system of the present invention, the number of feeds has been increased from 48 to 72 in a 30 inch diameter circular knitting machine.

In the drawings and specifica-tion there has been set forth the best mode presently contemplated for I_.

the practice of the present invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

-I,- 4 4

Claims

1. In a circular knitting machine including a multiple number of feeds spaced around the machine, and selector means positioned immediately in advance of each of said feeds and being operable to selectively position needles in one of three positions, knit, tuck and welt positions at each of said feeds, the combination therewith of two types of knitting needles, each of said two types of needles including a master butt, a knit selector butt, and a tuck selector butt, stitch cams for engaging said master butt and drawing all of said needles to a stitch forming level immediately following each of said feeds, two tuck selector cams positioned in advance of the position where said needles are drawn to stitch forming level, 5aid tuck selector cams being aligned to engage said tuck selector butts, two knit selector cams aligned to engage said knit selector butts, cylinders mounted for rotation and suppcrting said tuck and knit selector cams to selectively position the same in operative position, and wherein said tuck selector cam cylinders are positioned to overlap portions of said knit selector cam cylinders to permit said tuck and knit selector cams to be arranged at the closest possible lateral distance from each other and to thereby permit an increased number of feeds to be positioned around the machine.

2. A circular knitting machine according to Claim 1 wherein said knit selector cam cylinders are rotatable to an additional selected position to cause said needles to be moved inwardly to provide a support function for the prevention of stitch tovement when forming blister type stitch constructions.

3. A circular knitting machine substantially as hereinbefore described with reference to the accompanying drawings-i Published 1988 at The Patent Office, State House, 66.171 High Holborn, London WCIR 4TP. Further copies may be obtained from The Patent office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques Rd, St Mary Cray, Kent. Con. 1187.