Abstract: An electroviscous fan clutch (10) is employed as an accessory drive mechanism within a truck or automobile. A shaft (36), either driven by the engine or driving a load (31), carries a clutch member (14) arranged for fluid engagement with a body member (12) for the transmission of torque therebetween when electroviscous fluid is disposed in an operating chamber (45) defined by complimentary shear surfaces (40 and 44) in the clutch and body members. The clutch and body members are electrodes, connected to a source of high voltage potential (86), which establish an electrostatic field within the operating chamber to selectively vary the characteristic viscosity of fluid flowing therethrough.

Abstract: An electroviscous fan clutch (10) is employed as an accessory drive mechanism within a truck or automobile. A shaft (36), either driven by the engine or drivig a load (31), carries a clutch member (14) arranged for fluid engagement with a body member (12) for the transmission of torque therebetween when electroviscous fluid is disposed in an operating chamber (45) defined by complimentary shear surfaces (40 and 44) in the clutch and body members. The clutch and body members are electrodes, connected to a source of high voltage potential (86), which establish an electrostatic field within the operating chamber to selectively vary the characteristic viscosity of fliud flowing therethrough.

Abstract: A brake clearance sensing and control system (60) is provided for controlling brake released clearance (c) between a frictional braking member (6) and a rotary brake surface (15). System (60) includes an air flow rate sensor (18) operative to provide a signal (26) indicative of air flow rate through conduit (4) between a pressurized air source (2) and a gap (16) between frictional member (6) and rotary brake surface (15) that is a function of clearance (c) and which creates a variable air flow restriction. System (60) preferably includes a pulse control (20) operative to cause pressurized air to flow through conduit (4) only in the brake released condition and signal (26) is operative to either or both provide a warning signal (32) when clearance (c) has exceeded a predetermined maxiumum and to enable an adjusting mechanism to adjust clearance (c) to a desired predetermined clearance in the brake released condition.

Abstract: A caliper assembly for a sliding caliper disc brake of the open back type wherein the brake pad assemblies are positioned on opposite sides of the brake disc by a pair of washerhead bolts which pass at their free ends through bores in one side wall of the caliper for threaded engagement with nuts and which pass adjacent their head ends through radially outwardly opening slots in the other side wall of the caliper with the washerhead portions of the bolts received in counterbores which are formed in the outer face of the other caliper side wall and which communicate with the slots in that side wall.

Abstract: A disc brake (10) of the floating caliper type wherein the caliper (14) is slidably mounted on the torque plate (34) by two guide pins (60) which are received in complementary grooves (62, 66) in the torque plate and caliper and which are held to the torque plate by screw bolts (74) passing through bores (72) in the adjacent portions of the torque plate. The pins and grooves have sufficient wrapping engagement to allow limited sliding movement of the caliper on the pins while precluding separation of the caliper from the pins. When one guide pin is released by unscrewing the related bolts, the caliper may be pivoted about the other pin and then removed from the torque plate.

Abstract: A vehicular disc brake of the floating caliper type wherein the torque plate 14 mounting the caliper 13 includes an annular base 50 which is cut out to provide a slot 72, diametrically opposed radially extending arm portions 52 and 54, and caliper mounting portions 56 and 58 extending axially from the free outer ends of the arm portions. The torque plate is mounted on the axle assembly 12 of the related vehicle by utilizing the slot in the base portion to slip the torque plate over the axle assembly at a reduced diameter location thereon inboard of the axle flange 46 and thereafter sliding it axially outboard on the axle assembly to seat the outboard face 82, of the base portion against the inboard face of the flange.

Abstract: A wedge type actuator assembly for a disc brake employing a roller bearing assembly interposed between the wedge member and the tappet and including a generally U-shaped cage member embracing the wedge member and having a plurality of transversely extending slots each journally receiving a roller bearing. The wedge member includes raised ribs on each end face which guide on the adjacent housing surfaces. The end portions of the cage member guide on the portions of the end faces of the wedge member between the raised rib and the wedge face and include steps which coact with steps defined by the raised ribs to restore relative indexing of the roller bearing assembly and wedge member in the event the indexing becomes disturbed.

Abstract: A vehicular air disc brake of the wedge actuator type in which the wedge actuator is secured to the air motor by an annular fastener which is snap locked in place in a blind bore in the free end of the wedge actuator and which acts to secure the free end of the piston rod of the air motor to the wedge actuator in response to generally linear movement of the piston rod into the fastener. The fastener is split to allow insertion into the blind bore in the free end of the wedge actuator, and includes a plurality of finger portions which together define a single helical thread disposed within the blind bore; this single thread allows the threads on the air motor piston rod to ratchet therepast upon insertion of the piston rod, allows the piston rod to be threaded out of the fastener for disassembly purposes, and, in the event of inadvertent backing out rotation of the piston rod, allows the piston rod to reseat in the blind bottom of the wedge actuator brake in response to the next actuation of the air motor.

Abstract: A housing assembly for a wedge type disc brake in which the wedge actuator is housed in a radially disposed aluminum housing member which is clamped between the inboard end of a ferrous caliper housing member and a ferrous end plate by axial bolts passing through the end plate and the aluminum housing member for threaded engagement with bores in the inboard end of the caliper housing. The inboard face of the aluminum housing member has an opening opposite the wedge actuator which is closed by the end plate so that the inboard rollers of the roller bearing assembly interconnecting the wedge actuator and the push rod bear directly on the outboard face of the end plate. The braking force generated at the interface of the wedge actuator and the push rod is thus transferred to the end plate and absorbed by tensioning of the bolts, thereby relieving the aluminum housing of any significant tensile loading.

Abstract: An automatic clearance adjuster for a cam actuated vehicle brake. The adjuster is disposed in a pivotal lever and includes a worm and worm gear, an adjusting mechanism for effecting a clearance decreasing rotation of the worm during the brake apply stroke and a clearance increasing rotation of the worm during the brake release stroke, a two-way torque limiting ratchet clutch which slips to prevent rotation of the worm by the adjusting mechanism when the shoes are in contact with the drum, and a roller clutch which allows a predetermined amount of clearance increasing rotation of the worm by the adjusting mechanism during the brake release stroke and then locks up and causes slippage of the torque limiting clutch to prevent further clearance increasing rotation of the worm.