US2519372A - Picker stick stop mechanism - Google Patents

Description

g- 22, 1950 e. H. HUFFERD 2,519,372

PICKER STICK STOP MECHANISM Filed July 9, 1948 5 Sheets-Sheet 1 2, 1950 G. H. HUFFERD- 72 PICKER STICK STOP MECHANISM Filed July 9, 1948 I5 Sheets-Sheet 2 "7 A 5/ l gig 40 C WZL/ 75" Aug. 22, 1950" G. H. HUFFERD 2,519

PICKER STICK STOP MECHANISM Filed July 9, 1948 I5 Sheets-Sheet 3 12 74721? fur GQo ae H ZZY/ferd Patented Aug. 22, 1950 PICKER STICK s'ror MECHANISM George Hiram Hufferd, Shaker Heights, Ohio, assignor to Houdaille-Hershey Corporation, Detroit, Mich., a corporation of Michigan Application July 9, 1948, Serial No. 37,952 12 Claims. (01. 139-149) This invention relates to an improved mechanism for controlling the movements of a picker stick of a loom, and particularly to a stop mechanism for accurately positioning the picker stick in its shuttle catching position.

In my copending applications, Serial Nos. 37,950 and 37,951, filed concurrently herewith, there is described and claimed an improved mechanism for controlling the cyclic movements of the picker stick of a loom, characterized by the suspension of the picker stick by a plurality of pivoted links which are in turn mounted upon a primary bracket element secured to the rock shaft of the loom. A mechanism of this type is particularly adaptable to hydraulic checking of the excess energy imparted to the picker stick in its normal cycle of operation. The hydraulic checking arrangement described in my above referred to copending application permits the complete elimination of the check strap arrangements heretofore employed in looms and accomplishes the necessary checking of the movements of the picker stick with a substantial reduction in impact forces upon the various elements of the picker stick linkage together with a much higher degree of uniformity in the checking action than has been heretofore possible.

Those skilled in the art will recognize that the conventional check strap performed another function in addition to checking the excess energy movements of the picker stick. This additional function was the positioning of the picker stick in its intermediate or shuttle catching position. After the shuttle is thrown and the inward movement of the picker stick is properly checked, it was customary to return the picker stick to its intermediate or shuttle catching position through the bias exerted by a suitable spring, generally a torsion spring, which operates on the lower portions of the picker stick. The check strap was so arranged as to be engaged by the picker stick as it is returned outwardly by the torsion spring and thus stop the picker stick at the proper position for catching the shuttle when it is thrown back from the other side of the loom. With the complete elimination of the checking functions of the check strap accomplished by the utilization of an hydraulic check arrangement in accordance with the disclosures of my above referred to copending applications, it is therefore necessary to provide some means for accurately repositioning the picker stick at its intermediate or shuttle catching position.

Accordingly, it is an object of this invention to provide an approved mechanism for control of the movements of a picker stick of a loom, and particularly an improved stop mechanism for positioning the picker stick in its intermediate, shuttle catching position.

A further object of this invention is to provide a stop mechanism for a hydraulically controlled picker stick linkage to accurately and uniformly position the picker stick of a loom in its intermediate, shuttle catching position immediately following the checking of the inward, or shuttle throwing stroke of the picker stick.

Still another object of this invention is to provide an improved stop mechanism for picker stick linkages embodying the utilization of a resilient latch element carried by one link member of the picker stick linkage which cooperates with a stop member carried by another linkage member, and the proportioning of the resilient latch member in such manner as to effect the retention of the picker stick in the desired intermediate, shuttle catching position against the bias of the return spring, but to release the picker stick under the forces developed by the shuttle impact thereon, and to avoid interference with any other portion of the cylic movements of the picker stick.

Still another object of this invention is to provide a stop mechanism for a picker stick of a loom characterized by simplicity of construction and ease of manufacture, and which mechanism may be conveniently assembled to new or existing looms.

The specific nature of this invention, as well as other objects and advantages thereof will become apparent to those skilled in the art from the following detailed description taken in conjunction with the annexed sheets of drawings, on which, by way of preferred example only, are shown two modifications of the invention.

On the drawi gs:

Figure 1 is a side elevational view of an hydraulically controlled picker stick linkage incorporating a stop mechanism embodying this invention, showing the position of the components when the picker stick lies adjacent its innermost position;

Figure 2 is a view similar to Figure 1 but illustrating the position of the components when the picker stick is retained by the stop mechanism in its intermediate, shuttle catching position;

Figure 3 is an enlarged scale, top elevational view of the stop link or arm incorporated in the picker stick linkage of Figure 1;

Figure 4 is a side elevational view of a picker stick linkage incorporating a modified stop mechanism embodying this invention;

Figure 51s a perspective view of the stop link or arm incorporated in the mechanism of Figure 4; and

Figure 6 is an enlarged scale, partial sectional view taken on the plane VIVI of Figure 4.

As shown on the drawings:

Referring to Figure 1, the numeral II indicates the rock shaft of a loom while the numeral II indicates a conventional picker stick. Picker stick II is supported for oscillating movements with respect to the rock shaft II by a linkage which controls the movement of the picker stick so that the top end (not shown) of the stick traverses a substantially horizontal, straight line path. Such linkage, which is described in detail in my copending application. Serial No. 37,951, filed concurrently herewith, may comprise a primary bracket Il, rigidly secured to the rock shaft II, and a secondary bracket it which is connected to primary bracket ll by a pair of pivoted links II and II. The location of the pivot points of links II and II, as well as the relative dimensions of such links are selected in the manner described in my above referred to copending application, so that the picker stick II can move only in a path which will result in the upper end of the stick moving along the lay (not shown) in a substantially horizontal, straight line path.

The primary bracket ll defines three spaced pivoted bearings, Ila, Ilb and llc respectively. Pivot bearing Ila is located in slightly depending relationship with respect to rock shaft II and provides pivotal support for one end of the link ll. Pivot bearing Ila is preferably of bifurcated construction and thus surrounds the end of link II.

Pivot bearing Ilb is also of bifurcated construction and is located directly above the end of rock shaft I and provides pivotal support for the cylinder element ll of an hydraulic check unit ll. The hydraulic check unit ll is preferably of the type described in detail and claimed in my copending application Serial No. 37,950, filed concurrently herewith, and will therefore not be further described.

Lastly, pivot bearing Ilc is defined by a yokeshaped portion Ild of primary bracket ll and such pivot bearing is disposed in generally trianguiarly spaced relationship with respect to the pivot bearings Ila and Ilb and pivotally journals one end of the link I4. The secondary bracket I3 is of generally reversed E-shaped configuration It will be understood by those skilled in the art that conventional mechanism will be provided for producing the required cyclic movements of the picker stick II. For example, a power driven lug strap (not shown) having a looped portion surrounding the intermediate portion of picker stick Il may be provided to impart the high acceleration inward movement to the picker stick which is required for throwing of the shuttle. In such throwing movement, the picker stick II is shifted from its extreme outward position to its extreme inward position. After the shuttle is thrown, the inward movement of the picker stick II is checked by the hydraulic unit ll and the picker stick II is brought to rest approximately in the position indicated in Figure l of the drawings. As is well understood, a substantially identical arrangement of a picker stick and its associated control mechanism is provided on the other side of the loom for catching and throwing the shuttle.

It is then necessary that the picker stick be shifted outwardly to an intermediate position wherein it will catch the shuttle when the shuttle is thrown back from the other side of the loom. In accordance with this invention, a torsion spring 40 is provided which operates between any two relatively movable parts of the picker stick and.may be conveniently formed by riveted assemblage of two half parts, as indicated by rivets lie. The backslide of the upright portion of bracket II is suitably apertured, as indicated at Ild, so as to conform to and snugly partially surround the bottom portion of the picker stick II. Picker stick II is rigidly clamped in recess ltd by a plurality of U-shaped clamps II which are secured to secondary bracket II by bolts I'la.

Secondary bracket ll likewise defines three pivot bearings which are respectively located in the ends of its arm portions. Thus, a bifurcated pivot bearing Ila is formed in the end of the lowermost arm portion and pivotally journals the other end of link Ii. A bifurcated pivot bearing Ilb is mounted in the end of the top arm portion and pivotally Journals the end of a piston rod ll of the hydraulic check unit ll. Lastly, a pivot bearing lie is provided in the end of the intermediate arm and pivotally journals the other ends of links I4. All of the pivot bearings heretofore mentioned embody suitable pivot pins and grease fittings I.

control linkage, for example operating between secondary bracket I3 and link II, and is arranged to urge the picker stick II outwardly. To interrupt such outward movement of the picker stick II when the top of the stick is positioned at the proper shuttle catching position, this invention provides a stop mechanism indicated generally by the numeral 50. Such mechanism comprises a fixed stop pin il which may be mounted in any convenient element of the control linkage, such as the link I! which has an integral boss portion Iia formed thereon for receiving the stop pin II. To cooperate with the stop pin BI, a stop link or arm il is provided, which has one end Ila thereof pivotally Journaled to another member of the picker stick control linkage which moves relative to the link II during the cyclic movements of the picker stick. Such member may conveniently comprise the secondary bracket II. In such case, the end Ila of the stop link ll is pivotally joumaled on a pin III which is pressed into the secondary bracket It. The stop link Il is provided with a resilient latch element I! which may comprise a leaf spring member having one end portion Ila secured to the stop link ill by a clamp II and the other end portion bifurcated as indicated at Ilb to provide added resilience. The free ends of such bifurcated portions are angularly bent into a V-shape, as indicated at 53c. so as to provide an inclined latching surface to engage with the stop pin ll when the picker stick II is moved to its proper shuttle catching position by the spring ll.

To permit the convenient adjustment of the latch element 53 with respect to the stop pin II, such latch element may be adiustably secured in any one of a plurality of positions along the stop link El by having a slotted portion lid receiving a clamping bolt 54 and being clamped in assemblage on the stop link Bl by the clamping plate 55 which is secured thereon by the bolt It. The adjacent surface of the stop link Bl may be provided with longitudinally spaced, transverse grooves Elbwhich respectively accommodate downturned end portions 53s of the leaf spring 1g element 53 and thus permit a convenient indexing of the :position of the leaf spring element 53 along the stop link 52.

To adjust the effective tension with which the leaf spring latching element 53 resists displacement past the stop pin the clamping plate 55 is formed with integral extensions 55a which respectively overlie the secured end portions of the bifurcated portion 53b of the leaf spring element 53. An adjusting screw 56 is then mounted in each overhanging portion 55a and tightening of the screw 56 will urge thebifurcated portion 53b more tightly into engagement with the stop pin ii, and hence increase the force necessary to overcome the latching action On pin 5| produced by the resilient latch 53.

Suitable adjustments are made so that the resilient latch 53 is effective to interrupt the outward movement of the picker stick ll produced by the torsion sprin 40 and to sto the picker stick I I at the proper position to catch the shuttle. However, the retaining effect on the picker stick exerted by the leaf spring latching element 53 is readily overcome by the forces produced in the linkage by the impact of the shuttle on the picker stick ll. tion outward displacement of the picker stick H, which causes the inclined surfaces 530 of the resilient latch element 53 to ride up over the stop pin 54. However, before the bifurcated ends of the resilient latch 53 ride off the stop pin 52, the hydraulic check unit has operated to smoothly check the outward movement of the picker stick it and stop the picker stick H with the shuttle in the proper position in the shuttle box (not shown). ready for the inward, shuttle throwing stroke of the picker stick i i.

In the modification of this invention illustrated in Figures 4 through 6 of the drawings, a slightly different design of the hydraulic cylinder unit and the primary bracket is employed which is described in detail and claimed in my copending application Serial No. 37,950 filed July 9, 1948. So far as the operation of the stop mechanism is concerned, however, the modified primary bracket i2 and the modified check unit 20' function in an entirely identical manner to similar components heretofore described in connection with the modifications of Figures 1 to 3. With these exceptions, the picker stick control linkage is otherwise identical, embodying secondary brackets it, links M and i5 interconnecting the primary and secondary brackets and the torsion spring which normally urges the picker stick Ii toward its outermost position.

lhe stop mechanism 60, however, is of somewhat different construction. The stop pin 6| is now mounted in a bifurcated portion i2'e of the primary bracket l2 which also defines the lowermost pivot bearing l2'a. A stop link or arm 62 is provided to cooperate with the stop pin 6| but in this modification, such link comprises an elongated strip of resilient metal which is bent upon itself to provide parallel arm portions 62a and 62b which are in abutment over the greater portion'of the length of the stop link 62. The bight I portion 620 in this stop link is formed in a generally cylindrical configuration and this portion receives a cylindrically shaped, eccentric portion 63a of an eccentric pivot 63 which is mounted in transverse relationship in the secondary bracket l3. Eccentric pivot 63 also includes a head portion 63b which abuts against the side face of secondary bracket i3 and a reduced diameter shank portion 630 concentric with the head portion 63a Such action produces a high accelera- Hence the entire mechanism is again which projects through the opposite wall of secondary bracket l3 and is threaded to receive a locking nut 64 thereon. Hence, it is apparent that the angular position of the eccentric pivot 63 may be selectively adjusted by turning of this member relative to the secondary bracket l3 and the pivot 63 may be locked in any desired angular position by tightening of the nut 64. In this manner, the effective longitudinal position of the stop link 62 relative to the stop pin 6| may be conveniently varied.

The two arms 62a and 62b of the stop links 62 are clamped in abutting relationship by a U- clamp.65 which is tightened by a bolt and nut 66. Adjacent the free ends of the arm portions 62a and 62b, such arm portions are outwardly displaced as indicated at 62d and 62e respectively so as to permit these portions to surround and abut the stop pin 6i. The extreme end portions 62; and 629 are in abutment and inclined juncture portions 62h and 629 are thus defined between portions 62d, 62c and 62f, 629 respectively. Inclined portions 627:. and 627 respectively function as abutment surfaces and engage the stop pin 6! to retain the picker stick it in the proper intermediate, shuttle catching position against the bias of torsion spring 40.

When the shuttle strikes the top end of the picker stick H, the resulting impact forces are sufficient to spread the extreme ends 621 and 62g of the stop link 62 and permits such ends to ride up upon the stop pin 5!. Hence the primary checking of the outward movement of the picker stick H after the shuttle impact will again be accomplished by the hydraulic check unit 20.

In both modifications of this invention, it should be noted that the stop mechanism does not interfere in any manner with the operation of the picker stick control linkage during other portions of the cycle of movement of the picker stick. During the forward throw of the picker stick It, the stop mechanism is ineffective and exerts only a light frictional drag between the stop link and the cooperating stop pin. However, each time that the picker stick H tends to return to its outermost position under the bias of the torsion spring 40, the stop mechanism is effective to interrupt the movement of the picker stick H in exactly the proper position for catching the shuttle on the return throw. Of course, additional effort is required to overcome the latching action of the stop mechanism after the shuttle impact, but this additional effort is very desirable in that it helps to absorb the excessive impact forces imparted to the linkage by the impact of the returning shuttle.

From the foregoing description it is apparent that this invention provides an improved stop mechanism for picker stick linkages, and particularly for linkages of the hydraulically con- In both modifications of the introlled type. vention, convenient adjustment of the effective location of the shuttle catching position of the picker may be effected in a minimum time, thereby permitting the loom to be periodically adjusted to optimum operating conditions without incurring any substantial shut-down time to effect such adjustment. Furthermore, the stop mechanisms hereindescribed may be conveniently and economically manufactured by large quantity, low cost production methods.

It will, of course, be understood that various details of construction may be modified through a wide range without departing from the principles of this invention and it is, therefore, not

the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. In a picker stick linkage for a loom, a first linkage member movable with the picker stick, a second linkage member having a variable displacement relative to said first linkage member as the picker stick moves, a spring urging the picker stick to its extreme outward position, a stop secured to one of said linkage members, an arm secured to the other of said linkage members and extending adjacent said stop, said arm having yieldable latch means thereon engageable with said stop to retain the picker stick at its shuttle catching, intermediate position against the bias of said spring. said latch means being constructed to disengage from said stop under the force of shuttle impact on the picker stick.

2. In a picker stick linkage for a loom, a first linkage member movable with the picker stick. a second linkage member having a variable displacement relative to said first linkage, member as the picker stick moves, a spring urging the picker stick to its extreme outward position, a stop secured to one of said linkage members, an

'arm secured to the other of said linkage members and extending adjacent said stop, yieldabie latch means on said arm engageable with said stop to retain the picker stick at its shuttle catching, intermediate position against the bias of said spring, said latch means being constructed to disengage from said stop under the force of shuttle impact on the picker stick, and means for varying the effective position of said latch means relative to said stop, thereby permitting adjustment of the shuttle catching position of the picker stick.

3. In a picker stick linkage for a loom, a first linkage member movable with the picker stick, a second linkage member having a variable displacement relative to said first linkage member as the picker stick moves, a spring urging the picker stick to its extreme outward position, a stop secured to one of said linkage members, a stop link, means for pivotally mounting said stop link to the other of said members, said last mentioned means including an eccentric element angularly adjustable to shift the position of said stop link relative to said stop, and yieldable latch means on said stop link engageable with said stop to retain the picker stick at its shuttle match ing, intermediate position against the bias of said spring, said latch means being constructed to disengage from said stop under the force of shuttle impact on the picker stick. I

4. In a picker stick linkage for a loom having a primary bracket for attachment'to a picker stick and a secondary bracket for attachment to the loom, links interconnecting said brackets to control the movements of the picker stick relative to the loom and a spring urging .the picker stick toward one extreme position of relative displacement, the improvements comprising a stop mounted on one of said brackets, an arm pivotally secured to the other of said brackets and lying adjacent said stop, and yieldabie latch means on said arm engageable with said stop to position said bracket in an intermediate position against the bias of said spring, said intermediate position of said brackets corresponding to the shuttle catching position of the picker stick, said latch means being constructed to yieldingly disengage from said stop by the force resulting from the shuttle impact on the picker stick.

5. In a picker stick linkage for a loom, a first linkage member movable with the picker stick,

a second linkage member having a variable displacement relative to said first linkage member as the picker stick moves, a spring urging the picker stick to its extreme outward position, a

stop secured to one of said linkage members, a

stop link secured to the other of said linkage members and extending adjacent said stop, said 10 stop link including a leaf spring latch element having an inclined surface portion engageable with said stop to retain the picker stick against the bias of said spring in an intermediate, shuttle catching position, said latch element being prol5 portioned to disengage from said stop by the shuttle impact force on the picker stick.

6. In a picker stick linkage for a loom, a first linkage member movable with the picker stick,

a second linkage member having a variable dis- 2 placement relative to said first linkage member as the picker stick moves, a spring urging the picker stick to its extreme outward position, a

stop secured to one of said linkage members, a

stop link secured to the other of said linkage members and extending adjacent said stop, said stop link including a leaf spring latch element having an inclined portion engageable with said stop to retain the picker stick against the bias of said spring in an intermediate, shuttle catching position, said latch element being proportioned to disengage from said stop by the shuttle impact force on the picker stick, and means for varying the effective position of said latch means relative to said stop, thereby permitting adjust-.

as meat of the shuttle catching position of the picker stick.

7. In a picker stick linkage for aloom, a first linkage member movable with the picker stick, a second linkage member having a variable displacement relative to said first linkage member as the picker stick moves, a spring urging the picker stick to its extreme outward position, a stop secured to one of said linkage members, a stop link secured to the other of said linkage members and extending adjacent said stop, a leaf spring latch element, means for adjustably securing one end of said latch element to said stop link in any selected one of a plurality of positions along said stop link, the free end of said latch element being angularly disposed and engageable with said stop in latching relation. thereby retaining the picker stick in an intermediate, shuttle catching position against the bias of said spring, and said leaf spring element u being constructed to release from said stop under force of shuttle impact on the picker stick.

8. In a picker stick linkage for a loom. a first linkage member movable with the picker stick, a second linkage member having a variable diaplacement relative to said first linkage member,

as the picker stick moves, a spring urging the picker stick to its extreme outward position, a stop pin projecting from one of said linkage memhere, a stop link comprising a folded strip of 5 spring metal, said stop link having a bight portion defining a pivot bearing, means cooperating with said pivot bearing for pivotally securing said stop link to the other of said linkage members,

at least a portion of said stop link being disposed in surrounding relation to said stop pin and defining an angularly inclined surface engageable with said stop pin in latching relation, thereby retaining the picker stick in an intermediate, shuttle catching position against the bias of u said spring, said stop link being constructed to yieldingly disengage from said stop pin by the shuttle impact force on the picker stick.

9. The combination defined in claim 8 wherein said means for pivotally securing said pivot bore of the stop link to said other linkage member comprises an eccentric pin, and means for selectively angularly positioning said pin, thereby adjusting said stop link relative to said stop pin and varying the shuttle contact position of the picker stick.

10. A stop mechanism for a shuttle loom of the type having a picker stick, a picker stick control linkage and biasing means to urge the picker stick towards an extreme outward position, comprising, a stop on one linkage element, an arm connected to another linkage element and constructed to be cooperable with said stop to retain the picker stick at an intermediate shuttlecatching position against the outwardly directed bias.

11. A stop mechanism for a shuttle loom oi the type having a picker stick and a picker stick control linkage normally biased to place the picker stick at an extreme outward position, comprising, an arm connected to a relatively movable linkage member, said arm defining means cooperable with another linkage member to retain the picker stick at an intermediate shuttlecatching position against the outwardly directed bias, said means on said arm being constructed to permit movement of the picker stick control linkage and the picker stick under the force of a shuttle impact.

12. A stop mechanism for a picker stick linkage in a shuttle loom having one linkage member movable with a picker stick and another linkage member variably displaceable relative to the other linkage member as the picker stick moves, comprising an arm connectable to one of said linkage members, yieldable latch means on said arm cooperable with the other of said linkage members to retain the picker stick at a shuttlecatching intermediate position and means for varying the effective position of said latch means relative to the linkage members associated therewith, whereby adjustment of the shuttle-catching position of the picker stick may be made.

GEORGE HIRAM HUFFERD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,433,764 Kottemann Dec. 30, 1947 2,483,517 Balogh Oct. 4, 15949

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