SPRING-ACCUMULATED BRAKE CYLINDER

1. Spring-loaded brake cylinder, more particularly for rail vehicles, having a pre-loaded spring (3), which is supported so that axially it is fixed on the one side, a pre-loaded spring-tensioning piston (4), upon which the pre-loaded spring acts, a non-self-locking threaded spindle drive (9, 10), which is arranged between the pre-loaded spring-tensioning piston and the piston rod (6) of the tensioning piston, which is torque-loaded when the cylinder is braked and which consists of two parts, of which - relative to each other - the one part is held so that it is torsionally secure, while the other part is pivoted and may be braked firmly relative to the torsionally secure part by means of a locking coupling (20, 21; 27, 28) which may be shifted in an arbitrary manner and which comprises a free-wheeling system which jams in the direction of torque, and having a shifting device (23) which is arranged so that it is rotatable relative to the housing for disengaging the locking coupling, in which case the shifting device (23) is developed to disengage the locking coupling upon actuation, characterised in that the locking coupling (20, 21; 27, 28) which is developed so that it may be disengaged through rotation of the shifting device (23) in the direction of torque, is developed so that it is automatically trailing immediately behind, acting in opposition to the shifting device (23), and in that the one part (nut 10) of the threaded spindle drive (9, 10) is held on the piston (4) so that it is axially secure.