Spring-biassed hydraulic brake-actuator - has cup-shaped housing with sliding output rod mounted in it and acted on by piston and cylinder to oppose spring force

摘要

The brake actuator (1) comprises a housing (2) closed by a removable end wall (5). an output rod (3) is slidably mounted in the housing and is biased in the brake application direction by a spring (10). In normal use the brake is held off by hydraulic pressure in a cylinder (13) formed as a bore in the rod. In the brake off position of the actuator, the cylinder extends axially beyond the end of the housing. a piston (14) is rigidly supported on the end wall (5) and acts as a guide to the output rod. Hydraulic fluid is supplied to the cylinder (13) via a bore (18) in the piston.