Abstract: An adapter plate for a caliper disc brake assembly is attached to the inboard side of the axle flange of a vehicle axle housing. The adapter plate is generally C-shaped to allow mounting around the central region of the axle housing. The inboard positioning of the adapter plate allows mounting of larger brake calipers within a confined space. The caliper is connected to the axle housing by the adapter plate for the purpose of positioning the caliper relative to the rotor and resisting the torque developed by the action of the brake pads on the rotor. In order to adjust the lateral position of the caliper, the adapter plate, in one embodiment, has a pilot surface which allows the axle flange to be recessed within the adapter plate. In another embodiment, a secondary adapter plate bridges over the opening in the adapter plate to allow mounting of the adapter assembly to the entire bolt circle of the axle flange.

Abstract: An oil separator such as used in an air charging system includes a bypass assembly. During normal operation, airflow from an inlet to an outlet passes through the filter to remove oil and oil vapor from the compressed air. If a restriction or blockage occurs in the filter, as exhibited by a predetermined pressure differential across the filter, a bypass passage is opened to allow direct communication between the inlet and outlet ports. A spring defines the pressure responsive member that allows the filter to move away from the valve seat and establish communication between the inlet and outlet ports of the housing.

Abstract: A self-cleaning feature is provided for a trailer ABS modulator. Direct exhaust is provided through the piston or diaphragm to establish control line and control volume drain capabilities. This provides for moisture removal from the control line or control volume. Quick exhaust during normal service braking is also improved and, likewise, exhaust during the ABS mode is improved.

Abstract: A single piece metal clamp is provided for. The clamp includes an upper portion having a cylindrical section and a cross member section integrally connected through spaced apart left and right legs. The clamp also includes a lower portion having a base with a plurality of through holes. The upper portion and lower portion are integrally connected by a pair of spaced apart left and right legs, each leg having a corresponding right angle formed therein.

Abstract: An improved, air tight valve seat for a pneumatic brake system is achieved by using a plastic valve seat that is coined by the valve member. The valve member is a harder material, for example metal, than the thermo-plastic valve seat. The valve member is brought to an elevated temperature less than the melting point of the valve seat. The valve member engages the valve seat, coining the desired surface of the valve seat to conform it to the valve member. The heated valve member then remains in the valve assembly after coining.

Abstract: A testing system and method are provided for an electronically controlled braking system to determine whether the solenoids of each of the modulators are properly wired. According to the test, each modulator is tested in sequence. The exhaust solenoid of a modulator is actuated multiple times and the hold solenoid of a modulator is actuated once. Discrete signals will evidence whether the modulator solenoids have been properly wired.

Abstract: A modulator valve for an ABS system for heavy duty vehicles is disclosed. It uses non flow-through solenoid valve assemblies that simplify the machining and manufacturing costs associated with the present arrangement. This eliminates complex pilot passages and also achieves a quicker acting release of the brakes during normal service braking.

Abstract: A method and apparatus for monitoring the operation of vehicle brakes on a vehicle equipped with an electronic braking system as is commonly used to provide traction control (TC) and/or an anti-lock braking system (ABS). The speed at which a first wheel located on a first side of a vehicle rotates in relation to the speed at which a second wheel located on a second side of the vehicle rotates during particular braking events is examined. For each wheel, any difference or "error" in the rotation speed during the select braking events relative to the other side wheel is accumulated or integrated over a select duration until a threshold difference value is reached which indicates a malfunction at the subject wheel end. The accumulated difference is periodically adjusted to account for normal or acceptable levels of wheel speed variation.

Abstract: A cylinder is divided into two chambers by a wall to receive a pair of pistons. This reduces the stroke length and correspondingly reduces the linear speed of the piston. This leads to a reduced PV factor associated with degradation and wear of the piston rings. Moreover, the multi-cylinder arrangement provides the same performance in an oil-free compressor assembly without appreciably expanding dimensional constraints relative to known systems.

Abstract: A multi-channel wheel speed sensor having a custom integrated interface circuit. The interface circuit is configured with voltage programmable threshold adjustment allowing the circuit sensitivity to be specially tuned to detect wheel speeds in very specific ranges for a variety of applications. This feature can be implemented in ABS and/or traction control systems wherein in ABS mode a lower sensitivity adjustment can be used since wheel speeds below 5 mph do not need to sensed and processed precisely and in traction control mode very low wheel speeds, 1-1.5 mph are sensed and processed especially at non-drive wheels which provide speed reference for slipping or spinning drive wheels. The interface circuit is also configured with a test circuit for testing the integrity of the speed sensors and for providing information to the controller about the sensor/tone wheel gap.

Abstract: An air dryer and reservoir assembly for providing compressed air from an air compressor (20) on a heavy motor vehicle which includes an air dryer (14) connected to receive compressed air from the air compressor (20) and a secondary reservoir (12) for storing compressed air which passes through the air dryer (14), with the air dryer (14) and the secondary reservoir (12) being securely attached to a housing (16) to form an air dryer reservoir module (10). A primary reservoir (18) for storing compressed air from the air dryer (14) is located remote from the air dryer reservoir module (10). Components located within the housing (16) control air flow between the air dryer (14) and the primary and secondary reservoirs (18,12) and also monitor the pneumatic brake system circuits fed by the primary and secondary reservoirs (18,12). In the event of a failure of either of the pneumatic brake system circuits speed of the vehicle is limited.

Abstract: A desiccant cartridge for an air dryer of the type used for compressed air supply systems. The desiccant cartridge incorporates an internally disposed particulate filter element which functions to provide particulate filtration for air coming into the desiccant cartridge. The filter element further acts to apply a compressive loading against internal components within the desiccant cartridge insuring that these parts are firmly coupled and providing sealing engagement between components despite manufacturing tolerance variations in the component parts.

Abstract: A compressed air system includes an air dryer which dries compressed air before the compressed air is communicated to a reservoir. The air dryer includes a desiccant which is purged by using air stored in the reservoir. A pressure reference purge control valve is installed between the air dryer and the reservoir and includes a housing which defines a pressure reference volume. A pressure which is a function of the highest pressure level communicated to the reservoir is trapped in the reference volume. The valve permits purging only until a pressure is reached which is a predetermined pressure drop below the reference pressure level, whereupon purging is terminated.

Abstract: An air drying mechanism for a compressed air braking system includes a housing containing desiccant material, and a purge volume which stores air for backflowing through the desiccant to purge the latter of its moisture content. A flow regulating control valve is located between the purge volume and the desiccant to provide a constant flow rate of purge air through the desiccant during purging.