SPRING-LOADED BRAKE DEVICE FOR RAILWAY VEHICLES

摘要

SPRING-LOADED BRAKE DEVICE FOR RAILWAY VEHICLES A spring-loaded brake device particularly for railway vehicles has a brake valve to control the pressure in a brake line and spring-loaded brake cylinders that can be subjected to the action of pressure in the brake line against the force of a loading spring. At least one venting valve is connected to the brake line and the venting valve comprises a rapid acting valve which is controlled by pressure in the brake line to open a venting passage from the brake line to the atmosphere only when the pressure in the brake line is lowered from a brake release level to a level at which the brake cylinder makes braking contact. This venting passage is otherwise closed. The rapid acting valve thus removes air under pressure from the spring-loaded brake cylinders and flows this air to the atmosphere only at the beginning of a braking operation. Upon further application of the brakes the rapid acting valve has no effect and brake pressure is controlled by the brake valve.