AUTOMATISK BROMSMEKANISM-JUSTERANORDNING, SPECIELLT FOR RELSFORDONSBROMSAR

摘要

In a brake cylinder there is a reciprocating piston from which extends a non-rotatable sleeve surrounding a co-axial non-rotatable axially displaceable threaded shaft upon which is threaded a coupling nut. A pair of rotary couplings are provided on opposed sides of the coupling nut with the sleeve and the rotary couplings are actuable by axial displacement of the coupling nut. A stop ring is axially displaceable on the coupling nut and is supported opposite to the braking direction by a fixed stop. A second stop on the coupling nut is spaced rearwardly of the first stop a distance approximately equal to the contact stroke of the vehicle brake when the resetting device is in the inoperative position. To provide for single acting operation, the resetting device is provided with a spring which has one end acting against the stop ring and the other end acting against an abutment on the sleeve. To provide for double acting operation a compression spring is inserted between the stop ring and the coupling nut to load the coupling nut in the braking direction. This additional compression spring is mounted for rotation in at least one direction.