US2509676A - Check strap for looms - Google Patents

Description

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CHECK STRAP FOR 'LOOKS Filed Nov. 20. 1948 May 3o, 195o Miu??? Patented May 30, 1950 CHECK STRAP FOR LOOMS Ingram Dickinson, Atlanta, Ga., assigner to Southern Belting Company, Atlanta, Ga., a corporation of Georgia Application November 20, 1948, Serial No. 61,174

1 claim. l

This invention comprises a new and improved check or lug strap for looms of the type having a reciprocating shuttle operated by a swinging picker stick. The invention is also applicable to lug straps employed for impelling the picker stick of such a loom.

Check straps are required to serve the double purpose of checking the forward movement of the picker stick when the latter is impellng the shuttle across the loom and the rearward movement of the stick following the impact of the shuttle on its return movement to the stick.

The problem of designing a check strap in the form of a flexible loop within which the picker stick swings is one which has engaged the ingenuity of textile engineers for many years. If the contact surfaces at the ends of the strap are not evenly engaged by the contact faces of the picker stick swinging within the loop, one edge or the other of the strap is stretched and the bers broken so that the life of the strap is relatively short. When the bers are broken at one edge of the strap, the point of contact with the picker stick moves progressively down the face of the strap and the breaking process continues. Many attempts have been made to remedy this condition, as by cutting the straps with an initial curvature, but such expedients have increased the cost of the straps and made them more difficult properly to install and service.

By the present invention I provide a check strap of novel construction which is free of the objections noted and which, beside supplying a contact face extending across the full width of the strap, substantially reinforces it at both ends and so insures satisfactory operation for a long period of service.

The strap of my invention may be conveniently manufactured of any satisfactory material such as leather, fabric, or reinforced plastic compound. and may be of single or multiple ply construction. It is characterized by a strap of uniform crosssection closed at its ends in any desired manner and forming a flexible loop having equal length at both edges, combined with an insert or plug attached to the strap within its opposite ends in such a manner as to reinforce the strap, and being so shaped as to provide an inclined contact surface for engagement by a picker stick swinging within the loop of the strap. The insert or plug may be made of the same or different material from the body of the strap and is itself of novel and characteristic shape. It has U-shaped exterior surface conforming to the inner end surface of the strap and being cemented or otherwise attached thereto and to the adjacent side walls of the strap. It has a frusta-conical inner surface defining a continuous feather at one margin of the strap, and at the other a crescent-shaped edge which is disposed flush with the edge of the strap and which is of substantial thickness in its center portion and tapers symmetrically in both sides. It will be apparent that the strap itself may be prepared from stock of uniform thickness and then subsequently closed to form a symmetrical loop which may be then reinforced and given the desired divergent contact faces by merely cementing the inserts or plugs in place.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawings, in which.:

Fig. 1 is a view of the improved strap in .side elevation, partly in section, together with adjacent portions of a loom,

Fig. 2 is a cross-sectional view on the line 2-2 of Fig. 1,

Fig. 3 is a view in perspective of one of the inserts or plugs.

As shown in Figs. 1 and 2, the body of the check strap III is formed from a flat straight blank of suitable width and thickness. connected at its ends, for example. by a long beveled joint I I in one of its side walls. The joint may be formed by cementing together the beveled portions of the blank thus :forming a symmetrical elongated loop of equal length at both edges. It will be understood thatY by employing a blank of this shape, the formation of the loop itself is reduced to simplest terms and may be carried out rapidly and at minimum expense.

Inserts or plugs I2 are prepared independently from any tough resilient material such as leather, fabric, or reinforced plastic compound and are of such shape and size as to nt accurately within opposite ends of the strap. One of these is shown separately in Fig. 3, and it will be understood that a pair of right and left hand inserts is required for each strap. Each plug or insert is generally U-shaped in its contour, having one feather edge I3 and one crescent-shaped edge Il which is of substantial thickness at its center portion and tapers outwardly in both directions. Accordingly, the outer surface of the insert is cylindrical .in character whereas the inner surface is frustoconical and consequently defines the two dissimilar edges of the insert. The resulting solid is substantially defined by the surface described although the side portions of the insert extend forits supporting fingers.

wardly to a substantially straight Vfeather edge of equal width with the strap itself and are not -strictly included within the geometrical description of the insert. It will be noted that the side portions of the insert merge smoothly into the inner surface of the strap itself and so present no obstruction to the free movement of the picker stick within the loop. The fitted inserts are cemented in place at opposite ends of the loop and it will be seen that they supply a substantial re inforcement by reason of the added material supplied -to those portions of the loop adjacent to the contact surfaces against which the picker stick bears evenly and continuously over the full width of the strap.

The strap may be supported in any convenient manner in the loom. When used in high speed looms, where it has a particularly useful application, it is supported by three sets of fingers by which it is engaged at each side midway between its ends. These are shown in Figs. 1 and 2 where a carrying bar I5 is provided with a pair of downwardly projecting inside fingers I6' and a single intermediate outside finger I1. The fingers are hooked at their lower ends to support the strap and are so disposed as to flex its sides between them. 'I'he strap is thus supported securely but permitted to partake of a slight longitudinal cushioning movement in'sliding with respect to In Fig. 1 the picker stick is represented as swinging within the loop of the strap about an axis which brings its opposite faces into parallelism with the inner contact faces of the inserts I2 as it encounters them at the end of its stroke.

Having thus disclosed my invention and described in detail a preferred embodiment thereof, I claim as new and desire to secure by Letters Patent:

A check strap for looms comprising a closed loop of flexible material having parallel side walls and upper and lower edges of substantially equal length, and right and left hand U-shaped -plugs cemented within the opposite curved ends of the loop and extending symmetrically toward each other in opposite directions within the parallel side walls of the loop, each plug having a feathered upper edge and a lower edge of substantial thickness, thus presenting inclined contact surfaces for 'engagement by a picker stick swinging within the -loop and both sides of the kplugs being tapered and merging smoothly into the parallel walls of the loop and so presenting nto rliibstruction to the free movement of the picker s lc I INGRAM DICKINSON.

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

UNITED STATES PA'I'EN'rs

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