US2251401A

US2251401A - Parallel motion picker stick mechanism for looms

Info

Publication number: US2251401A
Application number: US362551A
Authority: US
Inventors: Harry A Davis
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-10-24
Filing date: 1940-10-24
Publication date: 1941-08-05
Anticipated expiration: 1958-08-05

Description

g 1943- H. A. DAVIS msmm PARALLEL MOTION PICKER STICK MECHANISM FOR LOOMS Filed Oct. 24, 1940 V s lnvenT 22 Hury A.DQ\/i Patenied Aug. 5, 1941 ZZSMGI i" F i Q fl hAR-ALLEL MOTION PICKER STICK MEGHANISM FOR LOOMS 6 Claims.

This invention relates to improvements in parallel motion picker stick mechanism for a loom and particularly to the bearing for the lower end of the picker stick against the pull of the lug strap or other mechanism by which the picker stick is moved or thrown to perform its function.

The picker stick is usually attached to a segmental shoe which rocks upon a flat rocker stand which is mounted uponthe lay rock shaft of the loom. The lower end of the picker stick is usually provided with a tongue which projects through this stand and engages an abutment on the rocker stand to hold the lower end of the picker stick against movement inwardly toward the loom side during the pull of the lug strap and the consequent picking motion of the picker stick. This bearing is subject to very trying conditions and if Worn or broken interferes with the accurate operation of the loom or prevents the operation of the loom. In usual looms the bearing or abutment is in the form of a wood plug or an iron plug anchored in the recess in the end wall of the rocker stand at the inner end of the slot, or in some types of looms a fixed pin or a roller is mounted transversely of the inner end of the slot adapted to be engaged by the tongue. Where abutment plugs are used the end of the plug becomes worn rapidly and uneven by the friction between it and the tongue of the picker stick, and where a pin or roller is employed there is only a line of contact between the surface thereof and the picker stick. In either case the abutment will wear out of line so that the shoe will become skewed with respect to the parallel shoe and the picker stick will improperly engage the shuttle and in many inthe usual spring actuated strap, which maintains thepicker stick tongue in connection with the abutment, will act as a hold-down to prevent separation of the rocker from the rocker stand, notwithstanding the jerks upon the lug strap and willinsure proper impingement upon the end of the shuttle and consequent accuracy of the flight thereof.

Another object of the invention is to provide an oscillatory abutment member having a wide fiat convexedly curved face of considerable area adapted to be engaged by the tongue of the concave end portion of the tongue of usual picker stick mechanism, and which can be mounted upon the rocker stand by merely boring a trans verse hole through it and inserting a pin therein to provide a pivot for the abutment member so that the present invention may be applied to usual types of looms without other modification than possibly the substitution of a tongue having a properly concave face to cooperate with that of the abutment in the event that the concave face of the original tongue does not conform to the curvature of the oscillatory abutment.

If the rocker stand is provided with a tapered socket to receive the usual wooden or iron plug upon which the lower end of the picker stick is fulcrumed, the present invention 'may be readily applied thereto by inserting into the socket an iron plug having a horizontally positioned cylindrical end adapted to fit a complementary socket in an oscillatory abutment member of the character described, thereby avoiding the necessity of boring alined transverse holes in the rocker stand to receive the pivotal pin for the oscillatory abutment member.

In usual constructions the tongue is clamped between the picker stick and the shank of the rocker shoe with an adjusting nut mounted in the upper end portion of the shank of the rocker bearing against the upper end portion of the tongue operable in conjunction with the clamping means to permit proper positioning of the icker stick. In such constructions the natural shrinkage of the picker stick loosens the parts to an appreciable extent, so that the set screw will wear a recess on the face of the tongue against which it has been jammed, requiring the re-tightening of the set screw to secure a tight assembly and as this wear continues eventually requires the replacement of the tongue only to have the same trouble repeated.

A further object of the invention is to provide means for overcoming this serious difficulty. This is accomplished in the present invention by providing a hardened surface, preferably a chillhardened spot, on the face of the tongue near its upper end where it is engaged by the set screw thereby preventing such wear andsaving of loss of time for repeated adjustment and replacement of the tongue and consequent expense of repairs and loss of production.

A preferred embodiment of the invention is illustrated in the drawing, in which,

Fig. l is a front elevation, partly broken away, of the lower right hand portion of a loom embodying a preferred form of the invention and showing the picker stick in its outward position;

Fig. 2 is a diagrammatic elevation showing the picker stick in a vertical or intermediate position;

Fig. 3 is a similar diagrammatic view showing the picker stick in an inner position;

The different positions of the picker stick illustrated in Figs. 1, 2, and 3, show the manner in which the engagement of the complementary curved bearing surfaces of the tongue and abutment, in combination with the spring actuated strap for returning the picker stick to outer position, acts as a hold-down for the picker stick assembly;

Fig. 4 is a sectional view on line 4l iv Fig. 1 viewed from the left toward the right, illustrating particularly the chilled spot on the tongue which is engaged by an adjusted screw; and,

Fig. is a detail view, partly in section, of a modified embodiment of the invention.

As the picker stick motion andits purposes and function in the operation of the loom are well known and; familiar to those skilled in the art, it is only necessary to illustrate and describe the same so far as is necessary to the disclosure of the present invention.

In the construction illustrated the right side I of the loom frame is shown as supporting the usual rocker stand 2 for the picker stick shoe. The rocker stand is mounted as usual upon the lay rock shaft and projects laterally from the loom side and is provided with a flat upper surface 3 on which the shoe of the picker stick mechanism rocks. The rocker stand is provided adjacent its outer end with a. longitudinal slot 4 through which the lower end of the picker stick extends. It is also provided with an upwardly extending tongue 5 which extends into a slot in the shoe and forms a guide for the rocking shoe or rocker. The rocker 6 may be and is of a usual construction having an arcuate sole 1 which rests and rocks upon the flat surface 3 of the rocker stand. The rocker is provided with an upwardly extending channel-shaped shank 8 and the picker stick 9 extends downwardly through the channel and through a slot in the shoe and also through the slot 4 in the rocker stand.

A channel-shaped tongue In, which fits upon the picker stick and between the walls of the channel-shaped shank of the rocker shoe, is clamped between the picker stick and the base of the channel of the rocker shoe by a bolt l I which passes through the tongue and picker stick and through a U-shaped clamping member l2, the flanges of which embrace the sides of the, picker stick, a nut I?v upon the bolt H serving when setup rigidly to secure the. parts together.

In order to provide for proper adjustment of the picker stick relatively to the shoe, an adjusting screw [4 is mounted in the upper portion of the shank 8 and is provided with a lock nut IE to, secure it in adjusted positions. In usual constructions this adjusting screw engages the face of the upper portion of the metal tongue which is of relatively softer material than that of the screw. By reason of the shrinking of the stick and the intense vibration of the picker stick as it is actuated by the lug strap mechanism the set screw rapidly wears a recess into the face of the tongue in usual constructions. One of the objects of the present invention is to prevent such wear. This is accomplished by providing a hardened and chilled spot I6 in the portion of the upper face of the tongue which is engaged by the set screw and it is found that this improvement, though apparently simple, substantially obviates the necessity of repeated adjustments of the set screw and clamping mechanism to maintain the picker stick in proper operating position.

The principal object of the invention as above stated is to provide a novel bearing mechanism between the tongue and an oscillatory stop or abutment which will provide extended cooperating bearing surfaces which will minimize wear and practically eliminate misalinement of the picker stick mechanism relatively to the shuttle and to the lay which is traversed by the shuttle, thus insuring accurate flight of the shuttle and preventing injury to the picker stick, the shuttle or to the guides and lay parts, thereby avoiding the expense of overhauling in order to secure a safe running shuttle.

This is accomplished in the embodiment of the invention illustrated in Figs. 1, 2, and 3, by providing an oscillatory stop or abutment comprising a preferably metal block I! of generally triangular shape which is pivotally supported upon a stud I8 which extends transversely across the slot 4 of the rocker stand and is mounted in suitable alined holes in the walls of the slot. Desirably a hardened and anchored bushing I9 is mounted on the stud l8 to provide a suitable journal for the oscillatory abutment. The outer face of the abutment block I! is provided with a wide transversely flat longitudinally convex face 20 and the lower end portion of the tongue H] has a wide transversely flat longitudinally concave face 2| which is complementary to the face 20 of the abutment block.

By reason of this construction extended contacting bearing surfaces are provided on the abutment and on the tongue which will avoid skewing of the rocker shoe and insure proper alinement of the picker stick mechanism with the lay at all times so that the accuracy of the flight of the shuttle will always be maintained.

The mechanism for pivotally swinging the picker stick to its outermost position is illustrated in Fig. 3 and may be and preferably is a usual strap 22 which is connected at one end to a hook 23 upon the end of the spring of a spring drum 24 which is mounted upon brackets 25 secured to and extending downwardly from the rocker stand. The other end of the strap 22 extends beneath the curved lower end 26 of the picker stick and is clamped to the picker stick between the U-shaped clamping member 12 and the outer face of the picker stick.

In usual constructions there is in the course of the sweep of the picker stick a time when the spring actuated strap between the lower end of the picker stick and the spring drum becomes practically horizontal and the hold-down effect of the spring and strap becomes ineffective and since at about this time the contacting surface of the spring with the plug abutment or roll assumes nearly a vertical position the pull of the lug strap between the pick arm and the picker stick will cause the shoe assembly to be raised or separated from the horizontal or parallel face of the rocker stand, thus causing improper engagement of the picker stick with the shuttle and causing the shuttle to wear badly at the top and at the same time to be distorted from a true parallel flight with respect to the lay. This will result often in bang-offs, broken shuttles, and spoiled cloth.

One of the objects of the present invention is to overcome these inherent troubles of older constructions and insure accurate flight of the shutv tle parallel to the lay which is so important to a good running shuttle.

This is accomplished in the present invention by so constructing, positioning and arranging the oscillatory abutment and the tongue that the lower end of the tongue extends at all times across a vertical plane through the axis of the stud l8 so that the constant pull upon the strap 22 in cooperation with the complementary

curved surfaces

20 and 2| of the oscillatory abutment and the tongue will exert a vertical resultant force in the vertical plane of the axis of the stud l8 which will prevent separation of the rocker shoe from the parallel face of the rocker stand, while permitting such constant contacting and sliding relation of th contacting

surfaces

20 and 2| during the entire rolling or rocking motion of the shoe assembly on the rocker stand throughout the complete sweep of the picker stick at each pick.

This hold-down action is illustrated in Figs. 1, 2, and 3, which show the relation of the parts in Fig. 1 when the picker stick is swung to its outermost position, in Fig. 2 when the picker stick is substantially vertical, and in Fig. 3 in which the picker stick is swung to its innermost position.

By reason of th present construction therefore the contacting surfaces of the tongue of the picker stick and the oscillatory abutment maintain a constant relation over an extended area which eliminates wear and because of the established relation of the curved contacting surfaces of the tongue and oscillatory abutment the under convex surface of th tongue against the convex surface of the abutment produces a constant hold-down effect for the entire rocker assembly throughout the entire pick and sweep of the picker stick.

One of the objects of the invention as above stated is to provide an oscillatory abutment of the character specified which can be readily applied to picker stick mechanisms of usual loom types of constructions such as those having an abutment in the form of a plug or an abutment roller which is engaged by the tongue of the pickor stick. In such usual loom constructions the lower end portion of the picker stick is usually concavedly curved and in the event that such curvature presents a proper arcuate surface an oscillatory abutment of the character above described having a convex face complementary to the curvature of that of the picker stick may be mounted upon a suitable stud which may be readily applied to the usual rocker stand by boring axially alined holes through the wall of the slot in the rocker stand at a proper distance from the inner end of the slot. In the event that the curvature of the lower end of the usual picker stick tongue of an old machine is too great or too small the present invention may be applied by merely substituting a new tongue having a curvature complementary to the curvature of the face of the abutment which may be mounted in the manner above described.

Where the rocker stand 3 of the loom, to which the invention is to be applied, is provided with a tapered socket 21 to receive a wooden or iron plug upon the end of which the picker stick is to be fulcrumed, the present invention may be readily embodied in such construction by inserting into said socket a steel plug having a tapered end portion 28 complementary to and fitting said socket with a reduced neck portion 29 integral with a cylindrical head 30 extending transversely of the slot 4 in the rocker stand. In this construction the oscillatory abutment member 3| is provided with a cylindrical socket 32 complementary to and extending more than half Way around the cylindrical head 30, thereby forming a pivotal connection for the oscillatory abutment member which will not become detached during its operation. The oscillatory member is provided with a curved face 33 complementary to the curvature ill of the lower end of the picker stick tongue. The operation of thisembodiment of the invention is the same as that above described in respect to Figs. 1, 2, and 3.

It will be understood that the particular embodiment of the invention shown and described herein is of an illustrative character and is not restrictive and that various modifications in form, construction or materials may be made within the spirit and scope of the following claims.

Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is:

1. In a parallel motion picker stick mechanism for a loom having a rocker stand provided with a longitudinal slot, a rocker mounted on said stand and a picker stick having a metal tongue secured to said rocker and extending through the slot in said rocker stand, a bearing. for said picker stick comprising an oscillatory abutment member pivotally mounted on said stand within said slot having a long longitudinally convexedly curved bearing surface and a complementary long ccncavedly curved bearing surface on the tongue of said picker stick contacting therewith substantially throughout its length and means for maintaining continuous engagement of said complementary surfaces during the actuation of the picker stick, whereby proper alinement of the picker stick mechanism will be maintained.

2. In a parallel motion picker stick mechanism for a loom having a rocker stand provided with a longitudinal slot, a rocked mounted on said stand and a picker stick having a metal tongue secured to said rocker and extending through the slot in said rocker stand, a bearing for said picker stick comprising an oscillatory metallic abutment member pivotally mounted on said stand within said slot having a long transversely fiat convexedly curved surface and a complementary transversely fiat concavedly curved surface on said tongue complementary thereto, and means for maintaining continuous engagement of said complementary surfaces during the actuation of the picker stick.

3. A parallel motion picker stick mechanism for a loom comprising a rocker stand provided with a longitudinal slot, an abutment member pivotally mounted on said stand within said slot having a wide transversely flat longitudinally curved convex surface, a rocker mounted on said shoe, a picker stick mounted on said rocker extending through the slot in the rocker stand and provided with a tongue having a transversely wide concave surface complementary to the surface of said abutment member and extending beneath the pivotal axis of said abutment memher, and resilient means for maintaining continuous engagement of said complementary surfaces during the actuation of the picker stick acting in conjunction with the engaged complementary surfaces as a hold-down to prevent separation of the shoe from the rocker stand and thus insure proper flight of the shuttle.

4. A parallel motion picker stick mechanism for a loom comprising a rocker stand provided with a longitudinal slot, a rocker mounted on said stand and a picker stick provided with a metal tongue having a wide transversely fiat concave end portion secured to said rocker and extending through the slot in said rocker stand, a stud mounted in the walls of said stand extending transversely across said slot, a metal bushing mounted on said rod and a metal abutment block having an aperture through the upper portion thereof fitting and rotatably mounted on said bushing and provided with a transversely wide longitudinal convex face complementary to the concave face of the tongue.

5. A parallel motion picker stick mechanism for a loom comprising a rocker stand provided with a longitudinal slot and having an abutment-receiving recess in the inner end wall of said slot, a rocker mounted on said stand and a picker stick provided with a metal tongue having a wide transversely flat concave end portion secured to said rocker and extending through the slot in said rocker stand, an abutment member seated in said socket having a cylindrical head, and a metal abutment block having a transverse aperture therethrough complementary to and rotatably mounted upon the cylindrical head of said abutment and provided with a transversely wide longitudinally convex face complementary to the concave face of said tongue.

6. An oscillatory abutment-block for a parallel motion picker stick mechanism for a loom having a rocker stand provided with a longitudinal slot, a rocker mounted on said stand and a picker stick provided with a metal tongue having a Wide transversely flat concave end portion secured to said rocker and extending through the slot in said rocker stand, comprising a metal block having a transversely wide longitudinal convex face complementary to the concave face of said tongue and adapted to be pivotally mounted upon a stud extending transversely across the inner end of the slot in the rocker stand.

HARRY A. DAVIS.