US3388565A - Stop motion with built-in slub catcher - Google Patents

Description

June 18, 1968 L. MISHCON STOP MOTION WITH BUILT-IN SLUB CATCHER Filed Jan. 30. 1967 INVENTOR Lester Mishcon BY I Witness ATTORNEY United States Patent 3,388,565 STOP MOTION WITH BUILT-IN SLUB CATCHER Lester Mishcon, Miami Beach, Fla., assignor to The Singer Company, New York, N.Y., a corporation of New Jersey Continuation-impart of application Ser. No. 544,951, Apr. 25, 1966. This application Jan. 30, 1967, Ser. No. 612,411

2 Claims. (Cl. 66-161) ABSTRACT OF THE DISCLOSURE A stop motion device for a circular knitting machine is described as embodying a slub catcher in the nature of a pivotal arm of the stop motion device. The slub catcher in one form of the invention takes the form of an elongated open ended slot, and as presently preferred, the dimensions of such slot are adjustable to accommodate various and sundry forms of yarns.

Cross references to related applications United States application Ser. No. 544,951, filed Apr. 25, 1966, of which the present application is a continuationin-part.

Background 0 the invention (1) Field of the inventi0n.Stop motion devices for knitting machines are designed to interrupt power to such machines when yarn tension exceeds, or is less than, certain predetermined amounts. Typical of known prior art stop motion devices with which the invention is practicable is the unit shown and described in United States Patent No. 2,515,479. Various causes will effect an increase in the tension of yarn fed to a knitting machine, least of which is a slub of yarn that gets caught while passing through a restricted passageway, i.e. a slub catcher, toward the needles of the machine. The invention is directed to defining the specific nature of just such a restricted yarn slub catcher passageway, and the relation of such slub catcher to its stop motion device, and also to the rest of the knitting machine.

(2) Description of the prior art.Prior to the invention of copen-ding application Ser. No. 544,951, slub catchers took the form generally of components with eyelets, or eyelets in combination with open ended slots, such being customarily situated between their respective cones of yarn and their stop motion devices. As a result thereof, each strand of yarn had to be of sufficient length from slub catcher to the needles of the knitting machine to permit proper yarn consumption after a given stop motion device was actuated, and while the machine was thereby slowed down to a complete halt. This attendantly resulted in the requirements for a substantial overall height for prior art knitting machines since the yarn from the cones had to pass upwardly through their slub catchers to the stop motion devices, and then back downwardly to the knitting machine needles. The cumbersome tallness of prior art knitting machines placed restrictive requirements on buildings etc. for housing such machines, and also made the placing of yarn in respective guides of stop motion devices a tedious job. To lessen the overall height of a knitting machine, copending application Ser. No. 544,951 has taught the use of an open ended slub catcher, without eyelet type guides, that so locates between a yarn cone and its stop motion device that the yarn, in the process of dropping from the slub catcher, and thereby actuating its stop motion device, provides the length of yarn necessary to allow proper knitting while the machine comes to a halt. Such an open ended slub catcher was comprised of a bent wire formed to provide a generally vertical slot, with its closed end upward, out of which the yarn could drop when a slub caught within the slot, and caused the stop motion device to release such yarn. While slub catchers of this type have proven quite satisfactory, it has been found that much effort is involved in assuring the vertical orientation of the slub catcher slot; and also the arrangement thereof is not as compact and sturdy as would be desired.

Summary of the invention Since stop motion devices use firmly supported pivotal arms tosupport their respective strands of yarn, and since such arms orient downwardly when pivoted in response to yarn tension, the present invention takes full advantage of such facts to avoid the problems which the technique of copending application Ser. No. 544,951 has presented. At least one pivotal arm of a stop motion device is designed to provide an elongated narrow open ended slot through which yarn is ordinarily adapted to pass, whereby when a slub gets caught in such slot, the tension within the yarn causes the stop motion yarn support arm to pivot, interrupting power to the knitting machine, and in so doing orients the slot downwardly to cause the yarn to drop from the stop motion device for consumption while the machine comes to a halt. Because the slub catcher of the invention is actually a stop motion yarn support arm that is firmly, though pivotally, supported by the stop motion device, such arrangement is not only compact, but of comparatively rugged construction. And since the slot of the slub catcher of the invention orients downwardly at the instant of yarn release, such slub catcher practices the invention of copending application Ser. No. 544,951, deriving all of its advantages in permitting of shorter knitting machines.

In its presently preferred form, the slub catcher of the invention embodies an adjustable piece that serves to vary the dimensions of the slot of the slub catcher yarn supporting arm, whereby the invention may be practiced for yarns of virtually any type.

A principal object of the invention is to provide a novel yarn slub catcher for use with the stop motion device of a knitting machine, from which slub catcher the yarn is adapted to be automatically released upon actuation of the stop motion device, this being to provide the requisite slack in the yarn whereby yard breakage will be prevented from occuring at the knitting instrumentalities before the machine can be stopped.

Another object of the invention is to provide a stop motion device having at least one arm adapted not only for supporting a strand of yarn, but also for serving as a yarn slub catcher.

Another object of the invention is to provide a stop motion device having at least one arm with an adjustable elongated slot that is adapted to serve as a yarn slub catcher.

The invention will be described with reference to the figures, wherein-- FIG. 1 is a perspective view of a stop motion device embodying the slub catcher of the invention,

FIG. 2 is a side elevational view of the stop motion device of FIG. 1, and

FIG. 3 is a slub catcher arm adapted to provide a presently preferred form of stop motion device according to the invention.

Referring to FIGS. 1 and 2, a stop motion device 10 for a knitting machine has a pair of spaced apart yarn support arms 12, 14, which arms are pivotally supported on a shaft 16. The shaft 16 mounts within the housing of the stop motion device 10 and is so spring-biased, by means within the housing of the stop motion device 10, that the arms 12, 14 ordinarily orient to bear generally against stops 18, 20 provided by a plate 22 as shown in FIG. 2.

Electrical power is supplied to the stop motion device via a contact clip 24'that is electrically coupled to a switch within the housing of the stop motion device 10, but which clip 24 is electrically insulated from such housing. The electrical switch, as indicated in both copending application Ser. No. 544,951 and United States Patent No. 2,515,479, is actuated by means of the yarn support arms 12, 14 and, when such arms are as depicted in FIG. 2, the switch permits of power to drive the knitting machine, whereas with the arms 12, 14 depicted as in FIG. 1, power is cut off from the knitting machine. The electrical circuit, including the aforementioned switch, is completed through the housing of the stop motion device 10, which housing is adapted to secure, by means of a flange 26, to a grounding ring of the knitting machine, such ring being adapted to reside within the cutout 28 of the flange 26.

The housing of the stop motion device 10 pivotally supports, also, a shaft 30 that is bent at 32, and is adapted to accommodate a counterweight 34. The shaft 30 supports a yarn engaging flange element 36, and is so biased by the counterweight 34 that, absent the presence of yarn Y across the flange element 36, the flange element 36 orients as shown in FIG. 2. Customarily, however, the yarn Y resides across the flange element 36 and between such element and a plurality of U-shaped guides 38 that aresecured to the housing of the stop motion device 10. The U-shaped guides 38 in combination with the yarn Y prevent the flange element 36 from taking its FIG. 2 position, whereby a switch (within the housing of the stop motion device) operable by rotation of the shaft 30 will actuate the stop motion circuit of the knitting machine. As excessive amount of yarn tension causes the arms 12, 14 to pivot downwardly to initiate the stop motion switch; too little yarn tension, as would occur were the yarn Y to break, causes the flange element 30 to pivot upwardly to initiate the stop motion switch. This is all well known in the art as indicated by both of the abovementioned references, and no claim is herein made to the inner workings of stop motion devices per se.

The invention is directed to a particularly way of producing yarn tension, whereby the stop motion device involved will become actuated in response to the presence of a slub etc. in such yarn. Referring again to FIGS. 1 and 2, the arm 12 is shown having a conventional U-shaped yarn guide 40; the arm 14 is shown however having an open ended guide slot 42 that is just sufficiently wide to accommodate the passage therethrough of the yarn Y. When for example a slub S of yarn passes easily through the guide 40 of the arm 12 to the guide slot 42 of the arm 14, such slub gets caught against the sides of the slot 42, thereby causing the tension of the yarn Y to build up as the knitting machine in question continues to demand yarn. Such tension causes the arms 12, 14 to be pulled downwardly, thereby initiating the stop motion switch. With the knitting machine continuing to knit while con1- ing to its halt, the yarn Y is pulled from the guide slot 42 (and also from the guide 40), thus releasing the flange element 36 to its FIG. 2 position to continue the stop motion command, and providing the slack length of yarn necessary for knitting purposes during the halting of the knitting machine. Reflecting on the teaching of copending application Ser. No. 544,951, a narrow open ended slot is again employed to effect yarn tension in response to a yarn slub S; further, the slot guide 42 releases the to knitting needles, the amount of yarn given up on actuation of the stop motion device 10 is sufiicient to permit proper knitting while the machine comes to a halt, this being before the slub S reaches the knitting instrumentalities of the machine.

Since yarns may be of different sizes and consistencies, it has been found advisable to provide adjustability to the slub catching slot of the stop motion device yarn support arm, whereby stop-motioning may be properly'etfected regardless of yarn type. Referring now to FIG. 3, a presently preferred form of slub catching arm 12 for use by a knitting machine stop motion device supports two spaced apart adjustment screws 44. The screws are adapted to reside in respective elongated slots 46 in an adjustment piece 48 and, when tightened against such piece 48, hold same in place against the arm 12'. For lightweight yarns, the piece 48 is so positioned that-the slot 42 is just sufliciently wide to pass the yarn, whereas for heavier yarns the slot 42 is made correspondingly wider.

While the invention has been described in its preferred form it is to be understood that the words which have been used are words of description rather than of limitation, and that changes within the purview of the appended claims may be made without departing from thetrue scope and spirit of the invention.

Having thus set forth the nature of this invention, what is claimed herein is:

1. In a stop motion device (10) for knitting machines, which stop motion device (10) is of the type having a yarn supporting arm (14) that is so shiftable that its longitudinal axis may point generally downwardly in response to yarn tension to actuate a stop motion switch thereof when such yarn tension is in excess of a predetermined amount,

the improvement wherein such arm (14) is provided with a substantially longitudinal open ended slot (42) that is adapted to permit easy passage of yarn (Y) therethrough, but which slot is sutficiently narrow to prevent passage therethrough of a yarn slub (S) or the like, whereby when a slub engages the slot said supporting arm is shifted downwardly to cause said yarn to fall free.

2. The apparatus of claim 1 including means (48) cooperative with said slot to vary the dimensions of said slot to accommodate easy passage therethrough of various forms of yarns, but not the passage therethrough of respective slubs of said various yarns.

References Cited UNITED STATES PATENTS 2,010,928 8/1935 Quick 66-163 2,362,781 11/1944 Tellerman 66 -163 2,434,864 1/1948 Powell 66l63 XR 2,515,479 7/1950 Vossen 2006l.l3 2,825,214 3/1958 Pernick 66-163 3,001,389 9/1961 Vossen 66163 FOREIGN PATENTS 51,630 6/1910 Switzerland.

WILLIAM CARTER REYNOLDS, Primary Examiner.

yarn when such slot is oriented generally downwardly; and since-no eyelet guides are employed from yarn cone

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