US3745792A - Warp knitting machine mechanism - Google Patents

Abstract

The yarn guide of a warp knitting machine is mounted for reciprocation through a first phase wherein the path of the yarn from the fixed supply cone to the yarn guide is shortened and a second phase wherein this path is lengthened. A mechanism is arranged in this path which comprises a yarn hook mounted for coordinated movement so that a stored length of the yarn is formed during the first phase and the stored length of yarn disappears during the second phase of the movement.

Description

United States Patent 1 Bergmann 1 Juiy 17, 1973 WARP KNITTING MACHINE MECHANISM [75] Inventor: Gerhard Bergmann, Hausen,

Germany [73] Assignee: Karl Mayer Textilmaschinentghrik G.m.b.II., Obertshausen, Germany 22 Filed: Dec. 6, 1971 211 App]. No.: 204,934

[30] Foreign Application Priority Data Dec. 12, 1970 Germany P 20 61 343.8

[52] U.S. Cl 66/86, 66/84, 66/125 [51] Int. Cl D04b 23/00 [58] Field of Search 66/125, 126, 84, j I 7 66/83, 86, 64, 61

[561 References Cited i v UNITED STATES PATENTS 9/1972 Jeffcoat 66/125 Licbrandt 66/86 X Lindley 66/84 FOREIGN PATENTS OR APPLICATIONS 1,007,935 5/1957 Germany 66/146 Primary ExaminerRonald Feldbaum Attorney-Kurt Kelman [57] ABSTRACT The yarn guide of a warp knitting machine is mounted for reciprocation through a first phase wherein the path of the yarn from the fixed supply cone to the yarn guide is shortened and a second phase wherein this path is lengthened. A mechanism is arranged in this path which comprises a yarn hook mounted for coordinated movement so that a stored length of the yarn is formed during the first phase and the stored length of yarn disappears during the second phase of the movement.

4 Claims, 3 Drawing Figures PAIENIEU U I 71915 3. 745 792 sum 2 OF 2 WARP KNITTING MACHINE MECHANISM The present invention relates to a mechanism for forming a stored length of warp yarn in the path of the yarn from a fixedly mounted yarn cone to a yarn guide of a warp knitting machine.

In known warp knitting machines, the yarn guide may be mounted for reciprocation through a first phase wherein the yarn guide is moved towards the cone so that the path of the yarn between the cone and the yarn guide is shortened and a second phase wherein the yarn guide is moved away from the cone so that the path of the yarn between the cone and the yarn guide is lengthened.

In machines of this type, the rotary speed of the main shaft, which controls the speed of the knitting cycles in a well known manner, is limited by the maximum speed of delivery of the warp yarn from its fixed supply, i.e., a yarn storage cone or spool, to the yarn guide which lays the yarn into the knitting needles during the knitting cycles. During each half cycle, the yarn is accelerated by the guide from standstill to a maximum speed and then decelerated again to standstill. At its maximum speed, the yarn is subjected to a maximum tension which is limited by the tensile strength or limit of extensibility of the yarn. Since the latter is rather low in the case of low-denier yarns in particular, the maximal machine speed obtainable cannot, in fact, be used.

While efforts have been made to equalize the tension of the yarn by storing a length of the yarn in its path from the cone to the yarn guide, they have not been successful because they failed to take into account the phased acceleration and deceleration of the yarn described hereinabove.

It is the primary object of this invention to provide an improved mechanism for forming a stored length of warp yarn in its path to the yarn guide of a warp knitting machine by equalizing the speed of the yarn throughout all phases of its movement.

The above and other objects are accomplished in accordance with the invention with a mechanism which comprises a yarn engaging device mounted for movement in coordination with the movement of the main yarn guide of the warp knitting machine and engaging the yarn in its path from a fixedly mounted yarn cone to the main yarn guide. The movements of the main yarn guide and the yarn engaging device are so coordinated that a stored length of theyarn is formed during the first phase of the main yarn guide reciprocation and the stored length of yarn is taken up or disappears during the second phase of the reciprocatory movement of the main yarn guide.

In this manner, the speed of drawing the yarn off the cone is maintained substantially constant, i.e. there is no yarn standstill and resultant yarn breakages at the points where the main yarn guide reverses its course during reciprocation.

In a preferred embodiment, the yarn engaging device is arranged to deflect the yarn in its path to form the stored length of yarn, for instance by mounting an auxiliary yarn guide for reciprocation parallel to the reciprocatory movement of the main yarn guide and spaced therefrom. The movements of the yarn guides are so coordinated that the auxiliary yarn guide precedes the main yarn guide in the direction of their movements.

' Advantageously, the auxiliary yam guide has a hookshaped yarns engaging member, and an endless moving chain carries the yarn guide.

The above and other objects, advantages and fea' tures of the present invention will be more fully understood by reference to the following detailed description of two now preferred embodiments thereof, taken in conjunction with the accompanying drawing wherein FIG. I is a schematic perspective view showing the essential parts of one embodiment of the apparatus of this invention:

FIG. 2 is a side view of another embodiment of the apparatus, again limited to a schematic showing of the essential portions differing from those in the one embodiment; and

FIG. 3 shows a detail of the apparatus.

Referring now to the drawing, wherein like reference numerals designate like parts functioning in a like manner in all figures, FIG. I shows a warp yarn guiding mechanism in a warp knitting machine according to one embodiment of the present invention, the knitting machine being otherwise conventional and, therefore, not illustrated.

As schematically illustrated, a plurality of knitting needles 4 are embedded in lead 3, the knitting needles being arranged in a straight array in the needle bed. A main yarn guide I is arranged for reciprocating movement parallel to the arrayed needles 4%. For this purpose, the yarn guide I is glidingly mounted on a pair of guide rods 5, 5 extending parallel to the needle bed 3, the yarn guide being attached to, and driven by, a cable 6 which is trained over guide pulley '7 and drive pulley 8. The drive pulley is keyed to rotary shaft 9 which has affixed thereto main gear III. The main gear meshes with ratchet II whose lower end is linked to one end of connecting rod I I whose other end is linked to crank 17 of main crank drive 13. The crank drive is coupled to the cam shaft 15 of the warp knitting machine by means of beveled gear transmission M. The machine shaft I5 controls the knitting mechanisms of the warp knitting machine in a known manner, its constant rotation being transmitted to the crank drive I3 by transmission 14 to crank the connecting rod I2. and thus to reciprocate the ratchet II vertically. This, in turn, causes rotary reciprocation of drive pulley b and the corresponding reciprocation of the yarn guide I in relation to the knitting needles t since cable 6 is driven by pulley 8 and is affixed to the yarn guide.

An auxiliary yarn guide I6 is mounted in the illustrated embodiment behind main yarn guide I and the warp yarn is also threaded through the auxiliary guide to form a stored length of the yarn during the operation of the mechanism. If desirable, the auxiliary yarn guide may also be mounted above or below the main yarn guide, instead of being arranged behind it.

The guidance and drive system for the auxiliary yarn guide Rh is substantially a duplicate of the guidance and drive system for main yarn guide 1. It also includes a pair of guide rods 5a, 5a whereon the yarn guide I6 is glidingly mounted for parallel movement to yarn guide I. The cable drive 60 is also actuated by the drive pul ley of the cable drive being keyed to rotary shaft 9, with an auxiliary gear 10:: on the shaft meshing with ratchet IIa which is connected to, and driven by, crank I7a of auxiliary crank drive Ida. As shown in FIG. I, the auxiliary crank 17a is angularly offset from main crank I7 so that, during the constant rotation of shaft 9, the auxiliary yarn guide I6 always is spaced from, and precedes, the main yarn guide I in the direction of the needle array.

FIGS. 2 and 3 show preferred features of such a warp yarn guide mechanism. In this embodiment, the auxiliary yarn guide 160 comprises a hook l9 and is affixed to an endless chain 18 which is trained about two pulleys and is constantly driven so that the hook 16a continuously moves first in one direction and then in the reverse direction about the pulleys. Such an auxiliary yarn guide drive is considerably simpler in structure and may be readily operated or switched out of operation according to the pattern requirements.

The auxiliary yarn guide, for instance the book 19 which is open at one side, seizes the warp yarn and, since it precedes the main yarn guide 1, or has a lead over it, produces a stored length of yarn. If a certain pattern requires omission of a warp yarn, a conventional device for either laying the yarn into the knitting needles or preventing the same is associated with the main yarn guide, such means forming no part of the present invention and not being illustrated. When such means interrupts the laying of. the yarn in the knitting needles, means is provided according to a preferred feature of the invention to prevent the hook 19 from seizing the yarn and thus to form a stored length of yarn. For this purpose, a yarn deflector 20 is mounted between the yarn storage cone (not shown) and the main yarn guide 1, the deflector being movable between an inoperative position 20a (shown in broken lines in FIG. 3) outside the path 2a of the yarn from the main to the auxiliary yarn guide and an operative position wherein the deflector extends into the path of yarn 2 to deflect the yarn and thus move it out of engagement with the auxiliary yarn guide hook 19, as shown in full lines in FIG. 3. The pivotal deflector 20 is operatively coupled with the patterning means which interrupts the laying of the yarn in the knitting needles so that it will be moved into and out of its operative position in response to the respective movements of this means.

When the deflector is in its inoperative or rest position 200, the path 2a of the yarn leads directly from the main yarn guide to the auxiliary yarn guide so that the mechanism of the present invention is in its operative position. In its operative position, the deflector 20 deflects yarn 2 sufficiently to lift it off the auxiliary guide so that the mechanism of this invention becomes inoperative.

The mechanism operates as follows when deflector 20 is in its inoperative position:

The warp yarn 2 is supplied to the warp knitting machine from a fixed cone 22 or spool whence it would normally move in a straight path to the yarn guide 1 of the machine as the same is reciprocated passed the array of knitting needles 4 and parallel thereto in a first phase wherein the yarn guide is moved towards the cone C so that the path of the yarn between cone and guide is shortened and in a second phase wherein the yarn guide is moved away from the cone so that its path is lengthened.

According to the invention, an auxiliary yarn guide 16, 16a is arranged in the yarn path between the cone and the main yarn guide 1, and since the auxiliary yarn guide precedes the main yarn guide during its reciprocatory movement, it will provide an extra length of yarn in this path during the first phase of the movement so as to form a stored length of yarn while this stored length of yarn will disappear during the second phase of the movement.

I claim:

1. A mechanism for forming a stored length of warp yarn in the path of the yarn from a fixedly mounted yarn cone to a main yarn guide of a warp knitting machine, the main yarn guide being mounted for reciprocation through a first phase wherein the main yarn guide is moved towards the cone so that the path of the yarn between the cone and the main yarn guide is shortened and a second phase wherein the yarn guide is moved away from the cone so that the path of the yarn between the cone and the yarn guide is lengthened, the mechanism comprising an auxiliary yarn guide mounted for reciprocation parallel to the reciprocatory movement of the main yarn guide and spaced therefrom, the auxiliary yarn guide engaging the yarn in said path, the movements of the yarn guides being so coordinated that the auxiliary yarn guide precedes the main yarn guide in the direction of their movements.

2. The mechanism of claim 1, wherein the auxiliary yam guide is arranged to deflect the yarn in said path.

3. The mechanism of claim 1, wherein the auxiliary yarn guide has a hook-shaped yarn engaging member, and further comprising an endless moving chain carrying the auxiliary yarn guide.

4. The mechanism of claim 3, further comprising a deflector mounted for pivotal movement from an inoperative position outside the path of the yarn between the auxiliary yarn guide and the main yarn guide, and an operative position wherein the deflector extends into said path to deflect the yarn and thus move it out of engagement with the hook-shaped yarn engaging member.

Claims (4)

1. A mechanism for forming a stored length of warp yarn in the path of the yarn from a fixedly mounted yarn cone to a main yarn guide of a warp knitting machine, the main yarn guide being mounted for reciprocation through a first phase wherein the main yarn guide is moved towards the cone so that the path of the yarn between the cone and the main yarn guide is shortened and a second phase wherein the yarn guide is moved away from the cone so that the path of the yarn between the cone and the yarn guide is lengthened, the mechanism comprising an auxiliary yarn guide mounted for reciprocation parallel to the reciprocatory movement of the main yarn gUide and spaced therefrom, the auxiliary yarn guide engaging the yarn in said path, the movements of the yarn guides being so coordinated that the auxiliary yarn guide precedes the main yarn guide in the direction of their movements.

2. The mechanism of claim 1, wherein the auxiliary yarn guide is arranged to deflect the yarn in said path.

3. The mechanism of claim 1, wherein the auxiliary yarn guide has a hook-shaped yarn engaging member, and further comprising an endless moving chain carrying the auxiliary yarn guide.

4. The mechanism of claim 3, further comprising a deflector mounted for pivotal movement from an inoperative position outside the path of the yarn between the auxiliary yarn guide and the main yarn guide, and an operative position wherein the deflector extends into said path to deflect the yarn and thus move it out of engagement with the hook-shaped yarn engaging member.

Images