Automatic slack adjuster with clutch release cam

摘要

An improved self-adjusting automatic slack adjuster for reducing slack in the brake of a vehicle is provided, in which an easily accessible external operating feature permits the automatic slack adjuster's one-way clutch assembly to be readily disengaged to allow smooth release and retraction of the brake shoes of a vehicle brake without damage to the one-way teeth of the clutch assembly. When the external feature is operated in a brake release direction, the motion of the feature is translated into a motion which axially displaces an output part of the one-way clutch away from an input part of the clutch a distance sufficient to disengage the parts' one-way teeth, thereby disengaging the one-way clutch to permit brake shoe retraction without resistance from the one-way clutch.

主权项

1. An automatic slack adjuster for a vehicle brake, comprising:
a housing configured to be coupled to a brake actuator for applying a brake actuating force to the vehicle brake; a worm gear set carried by the housing, the worm gear set including a worm gear and a worm shaft, wherein
the worm gear is arranged to engage a brake cam shaft of the vehicle brake, andthe worm shaft is arranged to transfer the brake actuating force from the housing to the worm gear; an axially-separable assembly having an input part and an output part, the output part being coupled to the worm shaft and the input part being coupled to a wear adjustment control mechanism such that when the input part and the output part are engaged, the worm shaft is capable of being rotated by the wear adjustment control mechanism; and an adaptor part carried by the housing and having an externally-accessible operating feature, wherein when the adaptor part is operated in a brake release direction, the output part is disengaged from the input part, wherein when the adaptor part is operated in the brake release direction, the adaptor part rotates and axially displaces the worm shaft a distance sufficient to disengage the output part from the input part by removing at least a portion of a load pressing the output part and the input part toward one another and maintain the input part and the output part disengaged from one another during operation of the adaptor part in the brake release direction.