METHOD AND MECHANISM FOR RELEASING HYDRAULIC ELEVATOR BRAKES

摘要

The invention provides a method and mechanism for releasing a hydraulically actuated elevator brake system (70), The brake release mechanism includes a rotary pump (2), a crank handle (4;45) to manually turn the rotary pump (2), a fluid supply port (30), a fluid return port (32), an output port (34) for connection to a cylinder (72) of the brake system (70), and a rapid exhaust valve (10) having an inlet port (12) connected via the rotary pump (2) to the fluid supply port (30), a cylinder port (14) selectively connectable to the output port (34), and an exhaust port (16) connected to the fluid return port (32). By turning the rotary pump (2), for example with the crank handle (4), a continuous flow of pressurised hydraulic fluid is delivered through the rapid exhaust valve (10) and onto the brake cylinder (72), thereby releasing the hydraulic brake system (70).