GB2105374A - Cam system for two cylinder circular knitting machine - Google Patents

Abstract

The present invention relates to a cam system for two cylinder circular knitting machines for hosiery goods and similar, with two feeds for reciprocatory knitting, of which each comprises a left and a right stitch cam (4, 5 and 9, 10) and a central cam (6, 11) for controlling sliders (1), below which are mounted intermediate jacks (3) and jacks. For the purpose of attaining a continuous motion of the slider and making possible the knitting at higher speeds, the present invention consists in that raising edges (151, 152) of a cam (15) for both directions of rotation are comprised within the path of swung out upper ends of intermediate jacks, the tops of said edges being situated between the neighbouring stitch cams of the two feeds, a rising cam (14) for raising said intermediate jacks being arranged in front of each rising edge, as well as the said pressbuttons (18, 19), for the purpose of swinging out the upper ends of intermediate jacks into the operative area of the rising edges. <IMAGE>

Description

SPECIFICATION Cam system for two cylinder circular knitting machines The present invention relates to a cam system for two cylinder circular knitting machines for hosiery goods and similar, with two feeds for reciprocatory knitting, of which each comprises both a left and a right stitch cam and a central cam for controlling the sliders, below which the intermediate jacks and the jacks are mounted.

Various types of two cylinder circular knitting machines are known, which are provided with two feeds for reciprocatory knitting. The needles intended for knitting the heel or the toe of the knitwork in reciprocatory manner, are controlled at this knitting phase only by sliders, which in turn are controlled by the stitch cams and the central cams of the feeds, and are transferred between the feeds by triangular cams, which are radially approachable. In one type of machine, the above mentioned cams are arranged within the path of the upper butts of sliders. This causes a considerable cover of the needle cylinder arch. In other types of machines, these cams are arranged within the paths of both the upper and the lower butts, thus achieving a lesser cover of the needle cylinder arch.However, in view of the continuation of cams for rising, or possibly retracting the sliders, the motion of the slider is not continuous, as impacts take place, alternately of the upper, and lower butts against cams. This is unfavourable upon increasing the speed of rotation of the needle cylinders. Together with increasing the speed of rotation it is necessary to change also the cam angles, thus enlarging the extent of both feeds, as well as their mutual distance.

The aim of the present invention is to constitute a cam system for circular and reciprocatory knitting at higher speed in two feeds with a minimum number of radially approachable cams.

According to the present invention there is provided a cam system for two cylinder circular knitting machines for manufacturing hosiery goods and similar, with two feeds for reciprocatory knitting, each of said feeds comprising a left and a right stitch cam and a central cam for controlling sliders, below which are mounted intermediate jacks and jacks, wherein rising edges of a cam for both directions of rotation are comprised within the path of swung out upper ends of intermediate jacks, the tops of said edges being situated between the neighbouring stitch cams of the two feeds, a rising cam for raising said intermediate jacks into the operative area of stationary pressbuttons being arranged in front of each rising edge, as well as the said pressbuttons, for the purpose of swinging out the upper ends of intermediate jacks into the operative area of the said rising edges.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawing of a cam system.

A known two cylinder circular knitting machine is provided with two feeds, which are adapted for reciprocatory knitting. The cam system, which comprises cam parts for controlling the sliders 1 of needles 2, cam parts for controlling intermediate jacks 3, and cam parts for controlling the jacks, which are not represented, as they do not relate to the subject matter of the present invention, is intended for the purpose of selecting and controlling the needles.

Within the path of the upper butts 1 a of sliders 1 are mounted the left stitch cam 4, the right stitch cam 5, and the central cam 6 of the first feed. In front of said cams, the radially approachable cams 7 and 8, and below them rising cam 9 are arranged. In the second feed, the left stitch cam 9, the right stitch cam 10, and the central cam 11 are arranged. Behind the left stitch cam 9, rising cam 12 is arranged. Furthermore, a number of further, not denoted cams is present, which have no relation with the present invention, and which are used only as auxiliary, or possibly knock over cams. Furthermore, four narrowers which are arranged in known manner in both feeds, are not represented.

Within the path of the lower butts I b of sliders 1 are mounted a radially approachable cam 13, a rising cam 14 for raising the sliders 1 upon reciprocatory motion in the direction of S2 and letting them through in the direction of rotation S1 of the needle cylinder as specified in Authorship Certificate No. 107. The further not denoted cams do not relate to the present invention and, therefore, are not specified.

For the purpose of controlling the intermediate jacks 3 cam 15 with the left rising edge 151 and the right rising edge 1 52 is intended, of which the tops are situated between the left stitch cam 4 and the right stitch cam 10 of the two feeds. The rising edges 151 and 1 52 are situated within the path of the upper swung out ends 31 of intermediate jacks 3. Furthermore, cam 1 5 is provided with two lowering edges 1 53 and 154, which are situated below the rising edges 151 and 152, and are situated within the path of butts 32 of intermediate jacks 3.Furthermore, within the path of the butts of intermediate jacks 3, the left rising cam 1 6 is mounted in front of the left rising edge 151, and the radially approachable rising cam 17 in front of the right rising edges 1 52.

Furthermore, within the path of the lower ends 33 of intermediate jacks 3 are arranged stationary pressbuttons 1 8 and 1 9 in front of rising edges 151 and 152. The said stationary pressbuttons 18 and 19 are mounted on guiding cams 18' and 19' at a height which corresponds to a raised intermediate jack 3 from the rising cam 16, or possibly 1 7. For the purpose of transferring needles 2 to the upper needle cylinder, the radially approachable rising cam 20, which is mounted within the path of butts 32 of intermediate jacks 3, is intended.

Upon reciprocatory knitting in both feeds, the cams specified above operate as follows: The radially approachable cam 8 is disengaged, as well as radially approachable cam 7 and radially approachable cam 20. The radially approachable rising cams 17 and 13 are engaged. Needles 2, or possibly sliders 1 are distributed in a known manner into operative and non-operative ones.

When the needle cylinders rotate in direction S, i.e. as upon rotary knitting, loops are formed by operative needles 2 in the first feed, on the left stitch cam 4. Needles 2 are lowered by the upper butts 1 a of sliders 1 and move along path A.

Behind the first feed, or possibly behind the left stitch cam 4, the sliders 1 and thus also the appurtenant needles 2 are in the closed position and are raised so that their upper butts 1 a pass through the second feed. The sliders 1 are raised by means of intermediate jacks 3. The said intermediate jacks 3, or possibly their butts 32 pass along path B, and in front of rising cam 17, their upper ends 31 are pressed into the tricks of the needle cylinder. Only those intermediate jacks 3, which belong to operative needles 2, are raised by rising cam 1 7 along path B, the others pass without changing their height position.The raised intermediate jacks 3 contact with their lower ends 33 the stationary pressbutton 1 9. Consequently, their upper ends 31 are swung out into the operative area of rising edge 1 52 and engaged thereon. Thereafter, the intermediate jacks 3 are raised by rising edge 152, as can be seen from the course of path C of the upper ends 31. The raised intermediate jacks 3 raise the sliders 1 and thus also the needles 2. Thus, the upper butts 1 a of sliders 1 move along path A and enter the second feed, and are lowered on the left stitch cam 9, the appurtenant needles 2 thus forming loops.

Further, all operative sliders 1, or possible needles 2 are raised by means of lower butts 1 6 by rising cam 13, as denoted by path A', and further by means of upper butts 1 a by rising cam 1 2.

After raising the intermediate jacks 3 by rising edge 152, said intermediate jacks are lowered by means of butts 32 by lowering edge 1 54 to their original height, as can be observed from the course of path B. In the further course, the upper ends 31 of each intermediate jack 3 are swung back into the tricks of the needle cylinder by chamfering 1 56.

Upon rotation of the needle cylinders in direction S', loops are formed by needles 2 at first in the second feed, in which the operative sliders 1 are lowered by means of upper butts 1 a by the right stitch cam 10, as can be observed from the course of path D of upper butts la. Behind this feed, needles 2 are raised by means of intermediate jacks 3 in an analogous manner as, when rotating in direction S, the needles behind the first feed. All intermediate jacks 3, or possibly their butts 32 from the operative group, which were raised by cam 20', pass along path E. The intermediate jacks from the operative group, which were not raised by cam 20', are situated at level of path B and raised by means of rising cam 1 6 into path E. The remaining intermediate jacks 3 pass through without changing their height position.Furthermore, the lower ends 33 of intermediate jacks 3 in path E are pressed by stationary pressbutton 1 8 into the tricks of the needle cylinder, and the upper ends 31 are swung out into the operative area of rising edge 1 51 , on which they become suspended during further movement, and are lifted along path C, raising simultaneously the sliders 1, or possibly needles 2 along path D. Further, the intermediate jacks 3 are lowered back to the original height by means of butts 32 on lowering edge 1 53 and swung back by means of abutment 1 58. By means of the upper butts 1 a of sliders 1, needles 2 are then lowered on the right stitch cam 5, and behind them, they are raised back by means of lower butts 1 b of sliders 1 by rising cam 14, as shown by path D' and by means of upper butts la by rising cam 9.

In the manner as specified above, reciprocatory knitting is performed in both feeds, while performing in a known manner, by means of not represented narrowing fingers and cam T, diminishing and addition of needles, for the purpose of forming a pouch for the heel or the toe of the knitted goods.

The main advantage of the present invention consists in that the raising of needles in the second, or possibly the first feed is secured by intermediate jacks, or possibly is not derived from the sliders, which are coupled to cams for controlling needles. In such manner, a larger space is gained, thus making possible to design cams with smaller angles of incidence, whereby the speed of knitting is increased. Further, this arrangement can be used for needle selection when knitting Jacquard or pearl patterns.

Claims (4)

1. Cam system for two cylinder circular knitting machines for manufacturing hosiery goods and similar, with two feeds for reciprocatory knitting, each of said feeds comprising a left and a right stitch cam and a central cam for controlling sliders, below which are mounted intermediate jacks and jacks, wherein rising edges of a cam for both directions of rotation are comprised within the path of swung out upper ends of intermediate jacks, the tops of said edges being situated between the neighbouring stitch cams of the two feeds, a rising cam for raising said intermediate jacks into the operative area of stationary pressbuttons being arranged in front of each rising edge, as well as the said pressbuttons, for the purpose of swinging out the upper ends of intermediate jacks into the operative area of the said rising edges.

2. Cam system as claimed in Claim 1, wherein below the said rising edges are made on the same cam lowering edges for acting upon the butts of intermediate jacks.

3. Cam system as claimed in Claim 1 or 2, wherein the rising cam for the direction of rotation corresponding to the direction of circular knitting is radially approachable, while the rising cam for the opposite direction of rotation is stationary.

4. Cam system for two cylinder circular knitting machines for manufacturing hosiery goods and similar, substantially as hereinbefore described with reference to the accompanying drawing.