Abstract: An improved approach to brake pad retention within a brake caliper is provided by a brake pad and brake caliper system in which brake pad retention features are provided on one of the brake pad or the caliper, with corresponding holes for receiving the retention features being provided on the corresponding pad or caliper part. The retention feature may be pin affixed to or integrally formed with the brake pad backing plate, about which a self-retaining spring bushing is located. The spring bushing and the corresponding retention feature receiving hole are sized so that the spring bushing is radially compressed when the brake pad is installed in the brake caliper by an amount sufficient to retain the brake pad in the caliper while still allowing the brake pad to move tangentially as necessary to transfer braking torque to the axle on which the caliper is mounted.

Abstract: An arrangement for securing a carrier for a brake to an axle housing of a vehicle includes a torque plate having an attachment portion securable to the carrier and an annular mounting section securable to a backing plate on the axle housing. The annular mounting section is provided with pluralities of alignment holes and mounting slots, permitting adjustment of a torque plate clocking angle. By way of a torque plate configured in accordance with this invention, clocking angle adjustments can be made in increments of under three degrees.

Abstract: A cast iron brake caliper with improved fatigue life, and a process and process equipment for pre-stressing a cast iron brake caliper to provide improved fatigue life, is provided. In the process, a load is applied to a cast iron caliper, where the load is high enough to locally yield and plastically deform the cast iron material, but not high enough to cause material failure, such as cracking. Upon load removal, residual compressive stresses in the cast iron caliper lower the mid-point of the stress range the plastically-deformed region of the caliper sees during in-service use, and thereby lowers the peak stress seen in this region, increasing fatigue life. The process permits a cast iron brake caliper to be designed to use less material and thus fit within constrained wheel rim envelopes, without the need to resort to high cost materials or other alternative design strategies.

Abstract: A bushing adapted to secure an O-ring seal in position relative to an area of a passage permitting reciprocation of a push rod forms a generally circular bushing body with opposed end faces. The end faces are separated by a gap so as to provide the bushing with an approximately C-shaped structure. The bushing includes a plurality of locking elements resistant to axial loads imposed on the bushing by the push rod disposed at least substantially within a corresponding plurality of recesses distributed around a circumferential exterior of the bushing. Solid ribs are interspersed with the locking fingers to resist radial loads imposed on the bushing by the push rod during operation. The O-ring seal is secured in position within the passage area of the passage by an end surface of the bushing.

Abstract: A cast iron brake caliper with improved fatigue life, and a process and process equipment for pre-stressing a cast iron brake caliper to provide improved fatigue life, is provided. In the process, a load is applied to a cast iron caliper, where the load is high enough to locally yield and plastically deform the cast iron material, but not high enough to cause material failure, such as cracking. Upon load removal, residual compressive stresses in the cast iron caliper lower the mid-point of the stress range the plastically-deformed region of the caliper sees during in-service use, and thereby lowers the peak stress seen in this region, increasing fatigue life. The process permits a cast iron brake caliper to be designed to use less material and thus fit within constrained wheel rim envelopes, without the need to resort to high cost materials or other alternative design strategies.

Abstract: A cast iron brake caliper with improved fatigue life, and a process and process equipment for pre-stressing a cast iron brake caliper to provide improved fatigue life, is provided. In the process, a load is applied to a cast iron caliper, where the load is high enough to locally yield and plastically deform the cast iron material, but not high enough to cause material failure, such as cracking. Upon load removal, residual compressive stresses in the cast iron caliper lower the mid-point of the stress range the plastically-deformed region of the caliper sees during in-service use, and thereby lowers the peak stress seen in this region, increasing fatigue life. The process permits a cast iron brake caliper to be designed to use less material and thus fit within constrained wheel rim envelopes, without the need to resort to high cost materials or other alternative design strategies.

Abstract: A brake actuator having a plurality of actuator housing portions includes a diaphragm seal partially delimiting a parking brake de-actuation chamber and retained between adjacent portions of the housing. To produce brake actuation upon depressurization of the parking brake de-actuation chamber, a push rod extends into and out of a service brake actuation chamber upon release of fluid pressure from and supply of fluid pressure to the chamber. A clip or similar element receivable over the end section of the push rod is securable on the end section to compress the diaphragm seal axially relative to the push rod against a seat carried by the push rod while permitting a radial inner edge of the diaphragm seal to remain spaced from an outer surface of the end section.

Abstract: A cast iron brake caliper with improved fatigue life, and a process and process equipment for pre-stressing a cast iron brake caliper to provide improved fatigue life, is provided. In the process, a load is applied to a cast iron caliper, where the load is high enough to locally yield and plastically deform the cast iron material, but not high enough to cause material failure, such as cracking. Upon load removal, residual compressive stresses in the cast iron caliper lower the mid-point of the stress range the plastically-deformed region of the caliper sees during in-service use, and thereby lowers the peak stress seen in this region, increasing fatigue life. The process permits a cast iron brake caliper to be designed to use less material and thus fit within constrained wheel rim envelopes, without the need to resort to high cost materials or other alternative design strategies.

Abstract: A slack adjuster for a vehicle drum brake includes a pinion that rotates about a worm axis whenever the slack adjuster pivots. Excess clearance is taken up upon commencement of the apply stroke, at an accelerated rate. This enables a larger amount of initial clearance to be built into the brake.

Abstract: A spring-type brake actuator for a pneumatically-operated vehicle brake is provided, with a brake actuator spring located on a front side of the actuator's intermediate flange, between a service brake actuator and a parking brake release actuator. The spring is captured between the intermediate flange and a retaining plate which is connected to the parking brake release actuator via a shaft through the intermediate flange. Because the retaining plate and parking brake release actuator are connected to one another on opposite sides of the intermediate flange, spring expansion is checked, thereby increasing safety during actuator production and servicing by virtually eliminating the potential for uncontrolled spring energy release. The actuator configuration also reduces structural loads on the rear portion of the housing and shifts spring and housing weight closer to the vehicle brake, permitting simpler designs and use of alternative materials, such as plastic or aluminum to lower costs.

Abstract: An improved seal/bearing arrangement employs an O-ring type seal which has segmented fingers. The seal ring has a recess which is sized to mate with a corresponding projecting lug of a bore use, for example, in brake actuator mechanisms. The seal ring can be made from synthetics such as polyamides and polyethylenes. The fingers are so arranged that locking of the seal rings in the bore occurs with insertion of a sliding, oscillating and/or rotating shaft or the like through the rings.

Abstract: In order to safely and conveniently assemble and service new design spring brake actuators having power springs located in the middle of the actuator, the actuator's rear chamber cover must be able to withstand high localized forces from tools such as power spring compression rods. A reinforcement and method for its installation is provided, in which a plurality of reinforcement plates is stacked on the rear chamber cover about a tool-insertion aperture, and the outermost plate is crimped about the aperture, thereby securing the plates to the rear chamber cover in a cost- and time-efficient manner. Preferably, the lip of the rear chamber cover aperture is stamped when the cover is formed such that the lip protrudes axially outward to help assure that the lip is captured between the crimped reinforcing plate on one side and the remaining reinforcing plates on the other side.

Abstract: A disc brake for a vehicle such as a commercial vehicle, wherein the brake caliper is provided with an actuator mounting flange surface which is parallel to the brake rotor, and a corresponding pneumatic or electric actuator is provided with a mounting flange surface which is angled, such that when mounted to the caliper, the actuator is offset at a desired angle relative to the caliper and the vehicle axle on which the caliper is located. This approach to brake design reduces brake caliper production and tooling costs by eliminating multi-stage machining operations, and lowers distribution and inventory costs by permitting standardization on a single “zero degree” caliper design, thereby offsetting additional costs associated with producing and distributing brake actuators with differing mounting flange surface angles.

Abstract: A disc brake for a vehicle such as a commercial vehicle, wherein the brake rotor extends from a hub end of an axle inboard a sufficient distance to place the friction surface of the rotor and the brake caliper outside the envelope of a wheel mounted at the end of the axle. The placement of the rotor friction surface and the caliper outside the envelope of the wheel enhances brake cooling, makes the brake more readily accessible for inspection and maintenance without significant vehicle disassembly, and permits the rotor outer diameter to be extended beyond the diameter of the wheel rim, thereby lowering brake components stresses and permitting use of lighter, lower cost brake components.

Abstract: For an air-operated disc brake there is provided an internal brake actuator stroke indicator which provides an indication, readily ascertained from outside the brake caliper, of the amount of actuator stroke remaining in a disc brake apparatus before a remaining available actuator stroke limit is reached. In one embodiment, the stroke indicator is a mechanical device, readable through a sight glass in a caliper port, coupled to the brake actuator in a manner which results in rotary motion of the indicator when the brake actuator is displaced through its stroke. Alternatively, the indicator may be a rotary sensor such as an electrical potentiometer coupled to the actuator, where the potentiometer sends an electrical signal indicative of the actuator stroke to an external display, such as a remote actuator stroke display at a vehicle operator's position.

Abstract: A driveline vehicle parking brake actuator including a reciprocable piston, a spring guide having a tubular distal portion telescopically received on the piston and a radial proximal portion which is telescopically supported within the housing by an annular wear guide, and nested cylindrical coil springs including an outer cylindrical coil spring biased between the housing and the radial portion of the spring guide and a nested inner coil spring having a greater spring rate biased between the spring guide and the piston functioning in series. The distal end of the piston is attached to a cable and the springs are compressed by hydraulic or pneumatic pressure acting against the piston.

Abstract: A method of monitoring the condition of a power spring of a pneumatic spring brake actuator of a vehicle by comparing the stroke of the push rod during normal braking and by actuating the parking brake, wherein a defective power spring is indicated when the difference in the push rod stroke falls below a predetermined minimum. The brake actuator may also include a sensor determining the push rod stroke and signal a defective power spring.

Abstract: A driveline vehicle parking brake actuator including a reciprocable piston, a spring guide having a tubular distal portion telescopically received on the piston and a radial proximal portion which is telescopically supported within the housing by an annular wear guide, and nested cylindrical coil springs including an outer cylindrical coil spring biased between the housing and the radial portion of the spring guide and a nested inner coil spring having a greater spring rate biased between the spring guide and the piston functioning in series. The distal end of the piston is attached to a cable and the springs are compressed by hydraulic or pneumatic pressure acting against the piston.

Abstract: An improved spring brake actuator which combines the advantages of piston and diaphragm-type brake actuators having superior performance at reduced cost. The improved spring brake actuator includes a tubular flexible diaphragm having one end secured between the rim portions of the cup-shaped housing and cover and an inverted second end portion which is received around the rim portion of a cup-shaped piston and secured in sealed relation with a flexible band. The power spring is received within opposed cup-shaped portions of the piston and cover and the rim portion of the piston is biased against a generally radial portion of the cover permitting use of a power spring having increased performance.

Abstract: A brake actuator having a stone shield located within the brake actuator housing and surrounding the brake actuator piston which dampens the impact of the brake actuator piston against the end wall surrounding the end wall opening. The damping stone shield includes an annular body portion having a diameter less than the brake actuator end wall opening and opening which receives the reciprocal piston of the brake actuator and an integral radial flange which overlies the inner surface of the brake actuator end wall opening. The annular body portion of the stone shield includes a first end portion extending at least partially through the brake actuator end wall opening having an annular groove surrounding the piston and damping the impact of the piston against the end wall surrounding the end wall opening. In the preferred embodiment, the annular groove extends through the first end portion of the stone shield and is bell-shaped or tapered in cross-section having a rounded end surface.