Abstract: A brake slack adjuster includes a housing defining a pair of intersecting bores therein. A gear is rotatably mounted in one of the bores, and is splined to a cam shaft which mounts a cam brake actuator. A worm shaft is mounted in the other bore and a worm is rotatable with the worm shaft to turn the gear. The worm shaft is supported in the bore by a surface tapering toward the open end of the bore that cooperates with a retaining ring which is received in a circumferentially extending groove circumscribing the bore to retain the worm gear in the bore. The retaining ring terminates in an arm which tapers toward the open end of the bore and engages flats provided on the worm shaft which are adapted to receive a conventional mechanic's socket to turn the shaft when the brake is to be adjusted. The arm yieldably locks the shaft against rotation, to prevent the adjustment from backing off after it is made.

Abstract: Automatic slack adjuster (10) for a vehicle braking system is provided with a bifurcated driving link (64) which drives an adjustment shaft (44) in a direction backing off the brake adjustment during the initial portion of the brake application stroke and effecting adjustment of the brake during the terminal portion of the brake application stroke. The mechanism connecting the link (64) to the shaft (44) includes an adjustment effecting lever (74) which is engaged with one arm (60) of link (64) through a lost motion connection. A back-off lever (80) is connected to the arm (62) of link (64) with little or no lost motion so that the back-off lever (80) is actuated during the initial portion of the brake actuating stroke before the lost motion between the adjustment effecting lever (74) and arm (60) is taken up. Levers (74,80) are connected to the adjustment shaft (44) by corresponding coiled clutch springs (86,92).

Abstract: The elimination of undesirable thermally induced changes of electrical characteristics of signal components is accomplished three operational amplifier circuits. The first operational amplifier provides electrical power to a system critical component and produces a reference output signal composed of the desirable function produced by the system critical components plus the undesirable thermally induced signal components produced by the changes of the electrical characteristics of two identical lead wires connected to the system critical component. The second operational amplifier circuit senses the voltage drop in one of the two identical lead wires attached to the critical component. The second operation amplifier produces a sensing output signal that changes in value with the undesirable thermally induced changes of the electrical characteristics of one of the lead wires.

Abstract: A wedge actuated drum brake assembly uses a wedge-shaped actuating rod and a roller cage slidably mounted thereon to transmit actuating forces from a fluid pressure actuator to a pair of friction elements. The actuating rod and roller cage are provided with a compression spring between the rod and the roller cage and an extension spring between the roller cage and the housing within which the actuating rod and roller cage are movably mounted. The extension spring opposes the compression spring during initial movement of the actuating rod to thereby cancel the spring forces acting on the cage. A flexible boot interconnects the rod and the wall of the housing and includes a bead that is clamped with the end coil of the extension spring between a shoulder on the housing and a portion of the fluid pressure actuator that extends into the housing.