Abstract: A parking brake, primarily for use with railway vehicles, including a friction clutch associated with a fast-travel nut which is locked by the clutch against rotation on a threaded spindle connected to a brake head, under a force exerted by a plurality of stacked Belleville-type disc springs. The spring load may be overcome by air pressure acting on respective faces of a plurality of serially connected pistons, which, in effect releases the fast-travel nut for free spinning to thereby accommodate axial displacement of the spindle during normal service application and release of the brakes.

Abstract: A hydro-pneumatic brake actuator having a friction element positionable by the power piston during the brake application stroke through a lost-motion connection therewith to establish a stop to limit movement of the power piston during a brake release and thereby provide a predetermined brake shoe clearance. In an alternate embodiment, a leaf spring is carried by the friction element to provide a cushioned stop for the power piston to prevent inadvertent displacement of the friction element, by reason of wheel out-of-roundness imparting a "kick-back" force on the power piston.

Abstract: This invention relates to a braking apparatus wherein the heat absorbing mass of a rotating braked element, such as a vehicle wheel, is increased by securing to, such as each wheel of the vehicle, a brake disc of such size as to constitute a heat sink capable of absorbing the heat generated by a pair of brake shoes when in braking engagement therewith, the periphery of the wheel forming a braking surface that is simultaneously engaged by a third brake shoe whereby the wheel constitutes a second heat sink capable of absorbing the heat generated by the third brake shoe.

Abstract: This invention relates to a disc brake apparatus wherein a plurality of brake shoes, that transmit braking force to a plurality of rotating discs, when worn to their minimum allowable thickness, may be replaced with new brake shoes, without disassembly of the disc brake apparatus, by unlocking, rotating through an angle of one hundred and eighty degrees, and thereafter relocking a plurality of pivotally mounted arms each of which may have attached to and detached from its respective ends a worn brake shoe and a new brake shoe, the rotation of each arm moving a new brake shoe to the position formerly occupied by a worn brake shoe thereby enabling the new brake shoe to transmit a braking force to the rotating disc formerly braked by the worn brake shoe.