Abstract: A combined power supply and electronic control circuit uses existing power supply wires to communicate ABS control signals between individual electronic control units, mounted at each wheel of a tractor and a trailer, and a central electronic control module. The central electronic control module communicates with the wheel mounted electronic control modules using low voltage hi-frequency AC carrier signals. Each wheel mounted electronic control unit is assigned a signature voltage and frequency, permitting simultaneous communications by all of the wheel mounted electronic control units with the central electronic control module.

Abstract: A drying material disposed in the passage of a compressed air system for removing moisture from air or gas includes a plurality of semi-rigid porous substrates impregnated with lithium chloride. The drying material is formed by preparing a saturated solution of lithium chloride and a nonflammable solvent. Porous substrata are contacted with the saturated solution to wet the substrata surface. The wet substrata are heated at a sufficient temperature for a sufficient duration to drive off excess liquid from the substrate. A desiccant comprising lithium chloride impregnated substrata is produced.

Abstract: An electric control valve for a heavy duty vehicle air parking brake system. The system uses latching electrically controlled solenoid air valves to control the parking brake systems of the tractor and trailer. The system allows electric control devices to be placed in the vehicle's instrument panel. The system maintains a previously set state of the system even in the event of a loss of electrical power to the controller. Indicator lamps provide park status information to the vehicle driver.

Abstract: An emergency brake backup system is achieved by selectively interconnecting the air suspension as an additional reservoir to the air brake system. That is, if the charging system or primary reservoir fails, compressed air in the air spring reservoirs is used as an energy source to supply the pressurized air required for brake function. This can be achieved with minor modification to existing tractor and trailer brake systems that employ air suspension assemblies.

Abstract: A control valve assembly for a heavy vehicle provides a symmetrical design that minimizes costs and provides a universal adaptation to a number of OEM configurations. The valve assembly can be used with different design platforms since symmetrical surfaces allow the valve body to be oriented as desired. Symmetrical mounting openings, alternate actuating lever mounting arrangements, and preselected angled orientation of the valve ports provide for the use of low-cost fittings that are useful in a wide variety of OEM configurations.