| 摘要 |
A single acting, clearance sensing slack adjuster for brakes is provided. The slack adjuster includes a displaceable brake actuation means (28), a rotatable driving member (74), and a rotatable driven member (82). A normally engaged positive clutch (64-66) provides a driving connection between the driven member and a rotatable adjustment member (50). The rotatable adjustment member is rotatable in a given direction to advance the brake friction member (32) to maintain the running clearance (38) within predetermined limits. The driving member is rotatable in the slack-decreasing direction of rotation thereof in response to greater than predetermined movement (102) of the brake actuation means. A force limiting coil clutch (80) couples the driving member to the driven member. Force limiting coil clutch (80) delivers torque in the given direction with a torque capacity which is less than is required to rotate the rotatable actuation members when the brake friction members are engaged but is greater than the torque required to rotate the rotatable actuation members when the brake friction members are not engaged. A fitting (104) accessible from the exterior of the housing (12) is provided for selectively disengaging the normally engaged positive clutch and for applying a rotational force to the rotatable adjustment member for manual adjustment of the brake slack. |
