US170273A - Improvement in trusses - Google Patents

Description

H. A. KIMBALL.

TRUSS .PatentedrNom 23,1875.

Wagga? N. PETERS, HDTO-LITHOGRFHER.

UNITED STATES PATENT QFFICE.

`HIBAM A. KIMBALL, `OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T() BENJAMIN C. EVERETT, OF SAME PLACE.

IMPROVEMENT IN l'RUSSVES..

Specication forming part of Letters Patent No. 170,27 3, dated November 23, 1875; application tiled November 5, 1875.

To all whom it may concern Be it known that I, HrRAM A. KIMBALL, of the city and county of Philadelphia, in the State of Pennsylvania, have invented a new and useful Improvement in Trusses, ot' which the following is a specification, reference being had to the accompanying drawings.

My invention, in the rst place, consists in curving the spring crosswise, commencingr to curve at the ends, where the spring is attened, gradually increasing the curve to the middle ot' the length of the spring, whereby to gradually increase its stiffness thereto. In the second place, the invention consists in the combination of the pad-holder with 011e end ot' the spring, by means of a swivel connected with an adjustable slide, whereby the slide-holder is adjustable in two directions at right angles to each other. It is held in its adjusted position by means of set-screws, as hereinafter described.

ln the accompanying drawings, Figure l is a top ricw ot' the spring A, having a padholder, C, in connection therewith. Fig. 2 is a front view of the same. Fig. 3 is a cross section ot' the pad-holder C and spring A, at the line mxot Fig. l. Fig. 4 is -a crosssection of the spring A at the line yy ot' Fig. l.

Like letters of reference in all the figures indicate the same parts. I

A is the spring, which is curved laterally except a short distance at its ends, where itis iat. The curvature commences at these nat parts, very slightly and gradually increases to the middle of the springs, whereby to i11- crease its stiffness in the middle.

In Fig. 4, which is taken at the point 2, the curvature, it will be seen, is much less than at the point 3, the middle of the spring. The curvature has gradually increased from the other end ot' the spring to its middle or point 3, in the same manner. At this point' the spring has such a curvature, taken in connection with the thickness of metal, as is requisite to give it the proper stiffness, and as the curvature gradually decreases from the middle of the spring to its ends, sensitiveness in the pressure of these resilient parts is effected. Or, in other words, the leverage of the length ot' the spring is balanced by the' change of l curvature, and thereby sufficient strength is given to the spring by the curvature with a minimum weight ot' material.

B is a slide on one end of the spring A, to which the pad-holder C is attached. The slide is fastened in its adjusted -position by means of the set-screw D. The lower end of the slide is slotted vto receive the flattened part ot' the pin F, which is connected with the cheeks a a by means of the joint-pin b. The pad-holder O turns on the rounded part at d ofthe pin F, as a lateral adjustment is given it either to the right or left. It is held in its adjusted position by means of the set-screwy H, which vpasses through the head or flange f of the pin F. g

For increasing or decreasing the pressure ot' the pad, the holder C is adjusted by means of v the set-screw I, the end ot which bears upon the slide B, as seen in Fig. 3.

I claim as my inventionl. The spring A, having a gradually-increased lateral curvature from its ends to the middle thereof, whereby to gradually increase the stiffness of thespring to that point, to balance the strength of the leverage of the spring by the change ot' curvature, substantially as set forth.

2. The combination ot' the pad-holder C, slide B, pins F and 71, and set-screws H and l, for an inward, outward, and a lateral adjustment of the pad-holders, substantially as set forth.

HIRAM A. KIMBALL.

Witnesses:

THOMAS J. BEWLEY, STEPHEN UsTIoK.

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