US2222351A - Loom picker - Google Patents

Description

Nov. 19, 1940. A. P. LEWIS 2,222,351

LOOM PICKER Filed March 14, 1939 2 Sheets-Sheet 1 Nov. 19, 1940. A. P. LEWIS,

LOOM PICKER Filed March 14, 1939 INVE TOR: MA4

2 Sheets-Sheei: 2

Patented Nov. 19, 1940 STATES FATE Pica 2,222,351 1.00M PICKER Arthur P.- Lewis, Fairhavem'Mass assignor to Roger W. Cutler, Boston, Mass.

Application March 14, 1939, Serial No. 261,752

materials as leather, rawhide, fiber, or various rubber compositions. Because of the nature of the service required of these devices, the rate of wear of the lug itself is relatively rapid, the strains imposed on the means for securing it to the picker stick are extremely severe, and it is, consequently, necessary to replace these lugs at relatively frequent intervals. The usual methods of attachment also produce considerable wear on the picker stick.

The present invention deals especially with these conditions. It aims to improve both the construction of the picker stick blocks or lugs and also the means for mounting them on the picker stick with a view to providing a more serviceable construction, while still maintaining the factor of manufacturing cost within entirely practical limits.

The nature of the invention will be readily understood from the following description when read in connection'with the accompanying drawings, and the novel features will be particularly pointed out in'the appended claims.

' In the drawings,

' 'holding the block in place;

Fig. 6 is a plan view of a strip from which the blocks aremade;

4 earlier figures: and

Figs. 8 and 9 are front and top views, respec' tively, of the form of the invention illustrated in F18. 'l.

Referring first to Figs. 1, 2 and 3,.theco n-" struction there shown comprises a lug or block' 2 mounted on the upper end of a picker stick 3.

The block 2 should be of a yielding, resilient character, so as to afford the necessary cushioning action as the shuttle strikes it and comes to rest while being boxed at one end of its flight height. Fig. '7 is a side view showing a slight modification of the form of the'dnvention shown in the without creating any substantial rebound. At the same time it must have the necessary coherence and solidity to propel the shuttle without damaging either it or the picker mechanism. For this reason I prefer to make the block 2 of some. 5

fibrous material united by a resilient binder into a solid block having the desired degrees of hard ness, elasticity, and the like. While it is contemplated that the block may be manufactured in various ways, and of a considerable variety of 10 materials, the best method which I have so far devised includes the steps of making a long, narrow strip, such as that shown at 6 in Fig. 6, but having a cross-sectional shape like that of the block illustrated at 2 in Fig. 3. This may con- 15 veniently be accomplished by assembling strips of a somewhat open mesh fabric, such as osnaburg, one upon the other, these strips preferably being cut on the bias and having previously been frictioned and skim coated with rubber prior 20 to being cut into strips. Because considerable heat is developed in one of these .blocks during operation, the rubber used should be a heat resisting compound possessing a high degree of adhesion. Raised edges or beads 5-5, Figs. 3 25 and 6, are formed at the opposite margins of the back of the strip 4 leaving a groove 6 between them to receive the forward edge of the picker stick 3. This may be done, for example, by properly proportioning the volume of material in such a way that the excess of fabric and binder will be forced upwardly during the subsequent molding operation so as to produce these raised edges, or narrower strips of fabric may be so assembled with the others as to produce essentially the same result after molding. Typical cross-sectional dimensions for the strip are seven-eighths of an inch in depth (from front face to the surface of the groove 6) and one and an eighth inches in width. The beads 5 need 40 be only approximately an eighth of an inch in The strip should be vulcanized under high pressure, a pressure of at least one thousand pounds per square inch being desirable. The composition and cure preferably are such that 45 the finished strip has a hardness, as measured on a Shore durometer, of somewhere between j and 100. For most purposes I have found that a value in the neighborhood of 97 seems to give the best results. 60

Blocks of suitable length, say one and threeeighths inches, for example, are cut from the strip, thecut forming the top surface of the block being made at right angles to the front face and that forming the bottom surface, Fig. 1, be- 65 ing at an acute angle to said face so as to afiord the necessary clearance with the raceway.

While the method above described produces a very satisfactory block or lug, it is contemplated 5 that the fiber body'may be made up in other ways and that other binders, such as the synthetic rubbers and those synthetic products known as Nylon, Koroseal, and othershaving the necessary resilience and permanence of adhesion, may be substituted for rubber. Such a block as that above described, however, has the neces sary resilience or yield, both radially and longitudinally with reference to thepoint of impact of the shuttle, and when made of a proper composition and correctly cured, gives a remarkably long life without the laminations splitting away from each other, which has been an important source of failure in prior art blocks or lu s regardless of the materials of which they are made.

As above indicated, an important problem in the production of a satisfactory picker organization consists inv the mounting of the shuttle engaging lug or block on the picker stick in such a manner that it will not work loose, will not Wear the' stick, and will present no projecting surfaces likely to catch the yarn. An important feature of this invention, therefore, resides in a novel mounting for a picker stick lug and this aspect of the invention is useful regardless of the specific composition or structure of the lug itself.

Referring again to Figs. 1, 2 and 3, it will be .observed that the block 2 is held against the front face of the picker stick by means of upper and lower U-shaped wire holders 1 and 8, respectively. These two members are similar; and the forward ends of eachare hooked into opposite sides of the block 2, while their rearward portions extend around the back of the picker 40 stick and there engage a resilient backer block or pad 9 preferably notched to receive the wires. These holders are made of wire having a. high degree of tensile strength and sufliciently stifi so that there is no danger of their hook-shaped 45 ends being bent out of shape under the relatively high working pressure. As shown in' Figs. 3

and 5, the forward ends of the holder 1 are bent backwardly and inwardly toward each other at angles of approximately 45, and they extend 50 into holes drilled or otherwise formed in the sides of the block. In addition, the lateral faces of the lug are grooved, as shown at III, to receive the wires so that they will not project beyond the side 'faces of the block.

The backer block or cushioning pad 9 may conveniently be made of rubber but should be considerably softer than the block 2 and have a wider range of yield and elasticity. It is molded with a. central cut-out at the back, bounded by 60 abrupt shoulders a. and b, Fig. l, providingseats for the curved ends of the holders 1 and 8. The latter naturally sink into the rubber somewhat and because of this fact and the presence of the shoulders, there is no tendency for them to slip relatively to the pad or backer block itself. Preferably a stiffening element of some appropriate surfaces of the parts 2 and 9 to be engaged with them, are coated lightly with oil or grease, both for the purpose of ultimately reducing the tendency of these parts to slip on the stick after having once been assembled thereon, and also to provide a certain amount of lubrication facilitating the assembly of these members on the picker stick.

It will be observed that when this assembling operation has been completed, the parts 2,1, 8 and 9 cooperate to encircle the upper end of the picker stick and they are elastically held in position by the engagement of this assembly with the front and rear edges of the ,stick. In other words, the holder has a resilient floating connection only with the picker stick through the elastic elements 2 and 9.. The parts are so dimensioned that the assembling operation requires a very considerable degree of compression of thebacker pador block 9, and a lesser degree of compression of the member 2. This condition is maintained during the life of the picker, and the legs of the holders 1 and 8 are constantly held under tension at all times and notwithstanding the tendency to relieve the compression on the backer block 9 at the instant of impact of the block 2 with the shuttle either in stopping or propelling it. There is, however, a tendency for such impact to move the block 2 upwardly and this tendency can be effectively overcome by any kind of a stop. The arrangement which I prefer is to thread a screw l3 downward diagonally into the picker stick at the upper end of the block, as shown in Figs, 1 and 3, where it holds the block against upward movement. Or, a screw can be threaded centrally through the picker stick from back to front, either above or below the part 9, where, its forward end will project a short distance into the block 2. If such a screw is made of small wire it will not materially weakenthe picker stick. I prefer the arrangement shown, however, for the reason that the screw 13 has no appreciable weakening action on the picker stick, it is easily inserted, is readily removed, and it -may be countersunk so as to be entirely out of the way.

In using rubber in a picker stick lug there is a tendency for the rubber composition to polymerize and disintegrate at the area of contact with the extreme point of the shuttle. This action seems to occur only at the very small area subjected to maximum pressure. I find that this difficulty can be overcome by forming a hole, such as that shown at ,in the block 2 so that the material which otherwise would be sub jected to this destructive action is removed. I also find that as wear progresses, the hole is deepened in a rearward and upward direction at an angle of approximately 15 with reference to a perpendicular to the front face'of the block,

and accordingly,I make the hole M at this angle or at any other angle necessary to suit specific conditions. It should also be observed that the points'ofattachment of the hook ends of the holders'to the block are entirely outside of the area exposed to the wear of the shuttle point.

It has been found in practice that this cong 2,222,851 struction gives exceptionally satisfactory service. planes instead of Not only does a block made in the manner above described possess the peculiar combination of learn have been held in place on the picker stick by screws or other metallic fasteners entering the stick from the side or rear, and this fact has been the cause of many of the troubles experienced with them. In the present construction the block is held on the stick fundamentally by parts encircling it and exerting their hold-' ing function by an elastic compression on the part of the stick so encircled. All that is neces-- sary, in addition, is some simple stop to prevent the block from moving upwardly on the stick. This stop is conveniently placed at the front of the stick where the motion tending to displace the block or lug 2 occurs, and it thus relieves the holders and the backing pad from strains to which they would otherwise be subjected.

The impact of the block with the shuttle is absorbed in compression of the former. Such compression has two effects on the holders; one. a very slight tendency acting on the hooks to move them apart due to the direction of the compressive force acting on'the inclined hooks, and the other a slight backward movement of both holders. The latter movement, however, is taken up by the expansion of the hacker block 9 so that all of the parts are constantly held in a taut condition. There is no outward or inward bowing or bending of the portions of the holders at opposite sides of the stick, they are always working in tension, and there is no substantial tendency for them to crystallize.

In referring to the impact of the block with the shuttle, it is recognized that under ideal conditions the block should push the shuttle rather than to strike it a blow. Nevertheless, the effect on the block is much the same in both cases, and the term impact should be understood accordingly. Also, the reference to striking the shuttle with the block'should be understood to refer to the operative engagements of these two members in practice rather than the strict definition of the term.

A further and important advantage of this construction is that the parts of the holders noi where project beyond the surfaces of the block 2, except at its back where they enter or leave the grooves. This is important in eliminating the presence of parts liable to catch on the yarn and in minimizing the opportunity for lint and fly to collect.

For the foregoing reasons this construction planes, as shown in Figs. 1 and 3, and these holders extend across the upper and lower ends,

. I .3 in approximately horizontal respectively, of the block. In other words, the

holders are hooked into the opposite lateral sides of the block I, but into the top and bottom sides "of the block 2'. At the rearward side of the picker stick I! the holders are engaged 'witha resilient backer block or cushioning pad I as in the construction previously described. This arrangement has the advantage, however, of permitting the holders to lie directly in contact with the opposite lateral surfaces of the picker stick v 3' and thus making a very compact arrangement offering little opportunity for accumulation of fly and little danger of catching in the yarn. At

the points where the holes accommodating the ends of the holders break into the front face of the block, as shown in Fig. 8, slots I] may be formed of such depth as to prevent the exposure of any metal part at the front surface of the block. This arrangement has essentially the same advantages of those above set forth in connection with Figs. 1 to 6.

While I have herein shown and described preferred embodiments of my invention, it will be evident that the invention may be embodied in other forms without departing from the spirit or scope thereof.

No claim is here made to the picker lug or block per se, but this element is claimed in my continuing application Serial No. 328,976, filed April 10, 1940.

Having thus described my invention, what I desire to claim as new is:

1. The combination with a picker stick, of a i yielding block for striking the shuttle, and means of said members extending diagonally backward toward the picker stick, and a resilient bad at the back of said stick around which said holders extend, said pad being grooved to receive said holders.

2. The combination with a picker stick, of a yielding block for striking the shuttle, and means securing said block in its operative position on said stick, said means including holders having hooks which project into said block at a substantially acute angle, said holders extending baokwardiy around the picker stick and lying closely against opposite sides of the stick.

3. The combination with a picker stick, of a yielding block for striking the shuttle, and means securing said block in its operative position on said stick, said means including holders having hookswhich project into the upper and lower portions of the block at a substantially acute angle, said holders extending backwardly across the top and bottom thereof.

4. The combination with a picker stick, of a resilient block for striking the shuttle and means securing said block against the front face of said stick, comprising a U-shaped metal holder having its forward ends anchored in the block at opposite sides thereof and terminating therein,'

and a resilient pad bearing against the rear surface of said stick and encircled on three sides by said holder, said pad being held in a compressed condition by said holder so that the holder has a resilient floating connection with the stick through said block and said pad.

5. The combination .with a picker stick, of a yielding block for striking the shuttle, and means securing said block to the front face of said stick comprising a U-shaped metal member straddling 5 said stick and having its forward ends projectin into the block from opposite sides thereoi. and

terminating therein. and a resilient pad at the back of said stick holding the curved end of said U-shaped member spaced from said stick so that said-member has a floating connection with said stick through said block and said pad;

AR'IHUR P. LEWIS.

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