US26583A - Self-ad justing counter-brace foe - Google Patents

Description

UNITED sTATEs PATENT OFFICE. i

JOHN GRAY, OF NASHVILLE, TENNESSEE.

SELF-ADJUSTNG- COUNTER-BRACE FOR TRUSS-BRIDGES.;

Specification of Letters Patent No. 26,583, dated-December 27', 1859.

To all whom it may concern:

Be it known that I, JOHN GRAY, of Nash` ville, in the county of Davidson, in the State of Tennessee, have invented a new and Iniproved Mode of Adjusting Counter-Braces in TrusseBridges; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The nature of niy invention consists in applying a cast iron socket at the top of each counter brace in a truss bridge in such a manner as to lift it up, and also providing the bottoni of the brace with a cast iron heel and key, which latter slips forward and under when the counter brace is drawn up.

To enable others skilled in the art tomake und use my invention `I will proceed to decounter scribe its construction and operation.

I construct my truss in the` ordinary Way with top and bottoni chords; upright or radiating posts and truss braces and counter braces. To prevent the counter braces from becoming loose and to increase tightness when the bridge is put into use I spike the iron socket, F ig. l, to the under side of the top chord and to the posts, making it exactly fit the angle formed by the two latter, as shown by the letters af" e a. I then lit and insert the end of the counter brace, and then through the holes a a in the sides of the socket, Fig. l, I drive two spikes into the brace. These hold the counter brace up firmly in position. Then I set under the end and on top ofthebottom chord, as shown at front` view, Fig.l2,`the cast iron heel against the posts.

In Fig. 2 back .'ewPBfCis the inclined surface upon which the` adjusting ,key,is1140 placed and slides.` `When. the heel,` Fig. 2,11., is set under the brace itleaves a` space they` size and 'shape of the key... :This key `and; the surface B C at Fig.` `2 are made smoothso y, that when the counter brace is liftedupfthe 145 1 key slides under and lillsthe space `justi as f l much as it is increased by lifting the brace."` To hold the counter brace in its proper poy i sition at the bottom I have side flanges c c" .p in Fig. 2 cast on theheelg These keep the key, as well as brace, in its proper positionf: When one end or portion cfa bridge near" the end is depressed by a weight andthe similar portion of the `other end is corre-3F33 g spondingly elevated the counter braces `are` drawn up and the key being relieved it slips under and fills up `theincreased spaceand holds the brace tight whenthe bridge cornes to repose again. kf What I claim as my invention, and desire to secure by Letters Patent, isf-` y ,i y b ,l The applicationto counter braces in truss IK C bridges of a socket at the top; aheel and key s at the bottoinbywhich the counter braces in truss bridges `are made selfftighteningand adjusting as herein described. b f 1 JOI-IN GRAYL" p I/Vitnesses: p ISAAC LITTEN,

SAML. SENY.` i

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