US3434509A - Check strap and method of making the same - Google Patents

Description

March 25, 1969 c. R. MESSER CHECK STRAP AND METHOD OF MAKING THE SAME Filed July 11, 1967 Sheet of 2 "nummuunuuu nunT! 1N VENTOR.

March 1969 c. R. MESSER 3,434,509

CHECK STRAP AND METHOD OF MAKING THE SAME Filed July 11, 1967 Sheet 2 of 2 me a n]! HI!" IH United States Patent US. Cl. 139161 Claims ABSTRACT OF THE DISCLOSURE Check straps of conical formation made from nylon or the like fabric, characterized by shrinking an elongated edge area of the strap, thus imparting an edgewise curvature thereto and then joining the ends of the strap.

This invention comprises a new and improved check strap of the type that is employed in loop formation with one side of its loop held at a fixed point in the loom while the other side is engaged in sliding contact by friction fingers.

I have found that the life of a woven strap of this type may be improved by imparting to it a preformed initially conical formation corresponding substantially with the angle of the picker stick at the end of its stroke. This ensures full transverse contact of the picker stick across the entire width of the strap and an even distribution of impact stress in the strap. It contributes therefore to reduce wear and to adapt the strap for use in high speed looms.

The desired conical formation may be imparted to a strap of woven nylon fabric by shrinking one edge of a straight strap in a marginal zone. As herein shown the shrinking step is effected by the application of heat and pressure to a selected predetermined area of the strap, but it would be within the scope of the invention to employ chemical shrinkage treatment. The shrinking step may be followed or preceded by a step of impregnating the strap in spaced areas in order to reinforce it against reeving by and impact of the picker stick.

As herein shown one impregnated area of the strap lies beyond the grip of the friction fingers and extends forwardly into the bend of the loop. It thus includes that portion of the strap which must reeve about the picker stick in its driving stroke and which must come entirely from that side of the loop which is arranged to move through the friction fingers, since the strap is fixed in the other side of the loop.

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 plan view of the check strap in its shape and location at the beginning of the driving stroke of the picker stick,

FIG. 2 is a similar view of the check strap as it appears at the end of the picker stick stroke,

FIG. 3 is a fragmentary view in elevation corresponding to FIG. 2,

3434',50'9 Patented Mar. 25, 1969 FIG. 4 is a plan view of a straight strap on a somewhat smaller scale,

FIGS. 5 and 7 are diagrammatic views suggesting the shrinking step, and

FIGS. 6 and 8 are plan views of the strap as impregnated and as curved by the shrinking step.

The strap 10 is close woven of nylon yarn or other tough thermoplastic synthetic resin and may be about two inches in width and in thickness. For present purposes the strap as shown in FIG. 4 may be considered to be about 23 inches in length and when doubled as shown in FIG. 1 form a loop with an overall length of about nine and one-half inches. The strap has slots or perforations 11 at both ends for the reception of a clamping bolt 16 which confines the strap to its loop formation and secures it to a fixed bracket 17.

As best shown in FIG. 6 the strap is impregnated with polyurethane or the like in areas 13 and 14 and these are somewhat critically located to lie in specific areas of the loop. If desired the straight strap 10 may be first lightly impregnated throughout its entire length, ironed between presser members 12 as shown in FIG. 5 and then subjected to more intense impregnation in the areas 13 and 14 which are shaded in the drawings,

Conical formation is imparted to the strap 10 by shrinking an elongated marginal area of the strap as by subjeoting it to heated pressing members 15 and this step causes the strap to become curved as shown in FIG. 8. When the ends of the strap are overlapped and secured by the clamping bolt 16 the resulting loop becomes conical as suggested in FIG. 3 and therefore full width contact of the picker stick 19 is insured.

As shown in FIGS. 1 and 2 the loop is held stationary at a point in one side by the clamping bolt 16 while the other side of the loop is free to pass back and forth in an undulating path between friction fingers 18.

The picker stick 19 is represented in FIG. 1 as just about to make contact with the left end of the loop, the loop being in relaxed condition.

In FIG. 2 the picker stick 19 is represented as having reached the end of its driving stroke and as having forced the loop into elongated condition. This has been done by drawing the material of only one side of the loop through the friction finger-s 18, since no part of the strap can be drawn from its fixed point determined by the clamping bolt 16. The result is that elongation of the loop takes place by movement of the strap from such a point A in FIG. 1 to some such point as A in FIG. 2. In this movement the strap is of course reeved about the picker stick throughout the length 13 of the strap which has been impregnated to withstand this severe treatment in the reeving area.

Having thus disclosed my invention what I claim as new and desire to secure by letters Patent is:

1. The process of making a check strap of conical formation from woven nylon fabric, which is characterized by the steps of shrinking one elongated edge area of a straight nylon strap thereby imparting a pronounced edgewise curvature to the strap and then uniting the ends of the strap.

2. A process of making a check strap as defined in claim 1, further characterized in that the shrinking step is carried out by heat and pressure applied to an elongated edge area of the straight woven strap while the 'body of the strap remains unheated.

3. A process of making a check strap as defined in claim 1, further characterized in that the woven strap is reinforced and smoothed by impregnating with polyurethane in areas adjacent to both ends of the straight strap.

4. A check strap constructed in accordance with the process of claim 1, secured in preformed conical loop formation at both ends at a fixed point and impregnated with polyurethane in an area reeved -by the picker stick in moving to the end of its driving stroke.

5. A check strap constructed in accordance with the process of claim 1, having its ends overlapped and secured together at a fixed point in a loom thereby imparting a preformed conical looped formation to the strap, and friction fingers engaging the strap at the other side of the loop, the strap being impregnated with polyurethane in that portion of the strap that is reeved about the picker stick in its driving stroke.

References Cited UNITED STATES PATENTS 2,741,273 4/1956 Robert 139l61 3,067,484 12/1962 Rasero et al 139-161 X 3,228,429 1/1966 Messer 139161 3,288,174 11/1966 Messer 139--161 3,297,514 1/1967 Poeschl et a1 16l-92 X JAMES KEE CHI, Primary Examiner.

U.S. CL X.R.

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