GB125191A - - Google Patents

Abstract

125,191. Curtis, J. N., and Sampson, E. D. March 12, 1918. Compensating for wear.-Relates to mechanism of the kind described in Specification 29600/10 for automatically taking up slack due to wear of the brake blocks of railway vehicle brakes, and comprising a pair of toothed cams a, b of which one a is pivoted upon the end e of the brake arm x and engages a pin f on the pull-rod g and the other cam b is pivoted upon a pin d fixed to the pull-rod g, and engages a pin h on the brake arm x. According to one feature of the invention, the pin h is carried by a link c connected to the arm x and slides in a slot in the forked end of the rod g. When the lever w is raised to apply the brakes the pull-rod is moved by the cam a engaging the pin f and by reason of the differential movement of the pin h with respect to the pullrod, the pin h takes up a tooth of the cam b if the movement of the pull-rod is excessive and as the brakes are released, the cam a also drops the extent of a tooth thereby shortening the effective length of the pull-rod. In the event of sluggish release movement of the mechanism, a pin l on a pair of links k connected to the pin e comes into contact with teeth n on the cam band so pushes the rod g. The pin l also prevents any substantial movement of the rod g except by actuation of the lever w. Any tendency of the cam b to remain in a position in which the pin h is on the crest of a tooth is prevented by the engagement during the release movement of the links k with an arm or wedge i fixed on the pin h whereby this pin is given a partial rotation sufficient to move the cam slightly about its pivot d.