| 摘要 |
An improved self-adjusting mechanism for a cable-operated vehicle brake is disclosed. The operating lever is pivoted about an axis on a frame member which carries a fixed sector. The lever carries a first pawl, which is adapted to releasably hold the operating lever in position with respect to the frame, and a second pawl which locks the lever to a sheave sector fixed to a sheave which winds up the brake cable upon pivoting of the lever. A third sliding pawl is mounted on the sheave sector. When the operating lever is rotated beyond a predetermined degree in setting the brake, the sliding pawl abuts a stop on the frame. This moves the sliding pawl with respect to the sheave sector. When the handle is subsequently returned to its rest position, the sliding pawl allows a limited amount of rotation of the sheave sector with respect to the lever, which occurs due to tension exerted on the brake cable by the brake shoe return spring. In this way predetermined limited amounts of slack in the cable are automatically taken up, and excessive spring force on the cable is avoided. |
