Ventilation device for a combined spring accumulator and operating brake cylinder

A ventilation device for a combined spring accumulator and operating brake cylinder, comprising:

• a spring-actuated brake cylinder including a first piston actuatable by a first spring, said first piston dividing said spring-actuated brake cylinder into a first pressurized-fluid chamber and a first spring chamber housing said first spring;
• an operating brake cylinder including a second piston actuatable by a pressurized fluid against a force of a second spring, said second piston dividing said operating brake cylinder into a second pressurized-fluid chamber and a second spring chamber housing said second spring;
• a piston rod on said first piston extending in the direction of said second pressurized-fluid chamber of said operating brake cylinder via a first through hole in a first wall separating said first pressurized-fluid chamber of said spring-actuated brake cylinder from said second pressurized-fluid chamber of said operating brake cylinder, said piston rod being guided sealingly in said first through hole by means of a sealing element annularly surrounding said piston rod;
• a first valve disposed at least one of in and on said piston rod of said first piston of said spring-actuated brake cylinder, said first valve being operable to effect ventilation of said first spring chamber of said spring-actuated brake cylinder is from said second pressurized-fluid chamber of said operating brake cylinder during depressurization of said first pressurized-fluid chamber of said spring-actuated brake cylinder, said first valve including a first working port, a second working port, a working chamber, a control chamber operable to admit pressure of said second pressurized-fluid chamber of said operating brake cylinder, and a movable valve piston, said first valve being movable against a restoring force from a first open position to a first closed position during injection of pressurized fluid into said second pressurized-fluid chamber of said operating brake cylinder, said movable valve piston of said first valve being drivable against a restoring force in closing direction of said first valve when pressure injected into said second pressurized-fluid chamber of said operating brake cylinder is admitted into said control chamber;
• a second valve operable to shut off said working chamber of said first valve from said second pressurized-fluid chamber of said operating brake cylinder, said second valve being movable from a second closed position when said first pressurized-fluid chamber of said spring-actuated brake cylinder is pressurized to a second open position during depressurization of said first pressurized-fluid chamber and associated movement of said first piston of said spring-actuated brake cylinder in the direction of said first pressurized-fluid chamber, said second valve being movable from said second closed position to said second open position when said second pressurized-fluid chamber of said operating brake cylinder is pressurized and said first pressurized-fluid chamber of said spring-actuated brake cylinder is depressurized, and when said first valve has reached said first closed position due to admission of pressure of said second pressurized-fluid chamber of said operating brake cylinder into said control chamber;
• a space defined at an end of said movable valve piston distal to said control chamber and bounded by said movable valve piston, said space being in communication with said second working port;
• and
• said movable valve piston including at least one passage, via which said first working port communicates with said space in said first open position of said first valve, said at least one passage connecting said first working port with said second working port, and being formed by (i) a recess in said movable valve piston extending from an end face of said valve piston distal to said control chamber into said valve piston, and (ii) at least a second through hole penetrating through a second wall of said valve piston bounding said recess and in communication with said recess.