Articulated railway car trucks

Abstract

A vehicle running gear with articulated, self-aligning, wheelsets having means providing elastic restraint of steering moments. This means ensures that the axles of the wheelsets, while free to yaw conjointly to assume a radial position in curves, are restrained from unstable steering motions when operating in a relatively straight line at high speeds. The wheelset bearings are each carried by a subtruck which is shaped to provide a steering arm, and these arms are movably coupled in a region intermediate the axles, to accommodate conjoint yawing motions of the axles with respect to each other and in the general plane of the axles. Particular attention is given to the importance of 'yaw' and 'lateral' restraints, between the two wheelsets of a truck and, in each of the disclosed embodiments, resilient means of predetermined stiffness is constructed and disposed to oppose departure of the arms from a position in which the wheelsets are parallel, while other resilient means reacts between the steering arms, in the region of their coupling, and opposes differential yawing, or lateral motion of the axles, across the line of general vehicle motion. Elastomeric pads or blocks are disclosed as providing the damping and, in some disclosed arrangements, the degree of restraint of the movements of one axle differs from the degree of restraint of another axle. In accordance with one disclosed feature, coupling is also provided between one steering arm and the vehicle body, to control yawing between the wheelsets and the body. According to another portion of the disclosure, brake improvements, for a railway vehicle, reduce brake shoe wear, and eliminate contact between the brake shoes and the wheel flanges.