Master cylinder lever for a hydraulic disc brake having on the fly dead-band adjustment

摘要

A master cylinder (10;200) for a bicycle hydraulic disc brake includes a cylinder (50;222) having a port (32) in fluid communication with a hydraulic fluid reservoir (28;208). The port opens to the cylinder between first (51;224) and second (52;226) ends of the cylinder. A piston (54;228) within the cylinder is movable between a select starting position with the seal (56;230) between the first end of the cylinder and the port opening with the piston a select distance from the port opening and a pressurized position with the seal between the port opening and the second end of the cylinder. A dead-band adjustment structure (20;74;225;244;264) is operatively associated with the piston for moving the select starting position to adjust the select distance between the port opening and the seal. A lever (16;206) is pivotably attached to the housing and is operatively associated with the piston to move the piston between the select starting position and the pressurized position as the lever is pivoted between a rest position and a fully-actuated position. A compensating structure (234;244) operatively associated with the dead-band adjustment structure and the lever maintains the lever in a select rest position as the dead-band adjustment structure is actuated to move the select starting position.