Abstract: A brake system and related components including a metering device are configured to regulate a control signal received from a brake control device such that a control valve delays the supply of a level of requested braking pressure for a prescribed amount of time. The metering device can be an inversion valve and orificed check valve in a control circuit adapted to allow relatively unrestricted flow until a threshold pressure is reached, after which pressure the inversion valve closes and the flow is metered through an orifice. This has the effect of allowing rapid brake actuation to a first level, and then slowing further application of the brake until full requested braking is achieved. An electronic control unit can also be configured to regulate a control signal to delay development of the requested brake pressure.

Abstract: An apparatus and method for preventing parking brake-caused disabling of a vehicle is provided. In at least one of the vehicle's parking brake release actuators' supply lines there is provided a flow arrangement which allows parking brake release fluid to flow to and from the release actuator when its supply line is undamaged, and restricts flow from the release pressure source when the line between the flow arrangement and the actuator is damaged. The flow arrangement may be a pilot-operated, non-graduated control valve, a combination of a pressure protection valve and a check valve arranged in parallel, a velocity-sensing check valve, or any other device or combination of devices which provide the damaged line shutoff or metering functionality. Such an arrangement prevents automatic application of the parking brake by releasing pressure from all of the vehicle's parking brake actuators, thereby precluding automatic vehicle immobilization following damage at one wheel end.

Abstract: A vehicle hand control brake valve includes a piston, positioned based on an engagement of a vehicle parking brake, a service brake actuation valve, and a control mechanism. The control mechanism mechanically interacts with the service brake actuation valve to set a position of the service brake actuation valve. A level of actuation of vehicle service brakes is set based on the position of the service brake actuation valve. The service brake actuation valve is set to a position to actuate the service brakes when the control mechanism is set to a latch position. The control mechanism only is latched in the latch position when the vehicle parking brake is engaged.

Abstract: A pneumatic brake system for a heavy duty vehicle is provided. The work brake system is operably dependent on a predetermined high trip brake system pressure and a predetermined reset brake system pressure. Upon actuation of the work brake system, when brake system pressure is greater than the predetermined high trip pressure, the work brake system is configured to deliver a pneumatic control signal to the second control valve to activate the service brake assembly. When brake system pressure is less than the predetermined high trip pressure, the work brake system is configured to deliver a pneumatic spring brake signal to the first control valve to activate the spring brake assembly and remove the pneumatic control signal to the second control valve. The delivery of the pneumatic control signal to the second control valve via the work brake system is prevented until brake system pressure exceeds the predetermined reset pressure.

Abstract: A heavy vehicle trailer antilock braking system module includes a module control port receiving a pressure signal, a module exhaust port fluidly communicating with atmosphere, a first switching valve, a second switching valve, a relay valve, and control logic. The first switching valve includes an input port and an output port. The first switching valve input port fluidly communicates with the module control port. The second switching valve includes an input port and an output port. The second switching valve output port fluidly communicates with the module exhaust port. A relay valve includes a supply port, a delivery port, an exhaust port, and a control port. The relay valve control port fluidly communicates with the first switching valve output port and the second switching valve input port. The delivery port fluidly communicates with the supply port and the exhaust port as a function of a pressure signal at the relay valve control port.

Abstract: A vehicle brake system for a vehicle comprises at least one source of pressurized air for pressurizing the vehicle brake system, and a brake actuator configured to receive air from the source of pressurized air. A control is operatively associated with the source of pressurized air for selective application of the brake actuator. A supplemental parking brake control system is in communication with the control and the brake actuator. The control system is responsive to data indicative of gradient and speed vehicle conditions. The control system is configured to send a signal to the brake actuator to allow gradient and speed dependent supplemental parking. The control system is configured to prevent application of the brake actuator.

Abstract: A system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability is disclosed. The system includes a reservoir of pressurized air and associated leveling valve that uses a relay valve to improve refill times when the vehicle returns from a dump mode operation to normal operation. The process reduces pressure in one or more of the axles when maneuvering the vehicle at predetermined slow speeds and maintaining that first predetermined pressure while the other axle(s) is at a greater pressure than the first axle. By preventing complete exhaustion of pressure from the suspension system, restoring air pressure is attained more quickly. Also, use of a relay valve enables higher flow rates to improve the refill time of the pneumatic suspension system after the dump operation.

Abstract: A system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability is disclosed. The system includes a reservoir of pressurized air and associated leveling valve that uses a relay valve to improve refill times when the vehicle returns from a dump mode operation to normal operation. The process reduces pressure in one or more of the axles when maneuvering the vehicle at predetermined slow speeds and maintaining that first predetermined pressure while the other axle(s) is at a greater pressure than the first axle. By preventing complete exhaustion of pressure from the suspension system, restoring air pressure is attained more quickly. Also, use of a relay valve enables higher flow rates to improve the refill time of the pneumatic suspension system after the dump operation.

Abstract: A system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability is disclosed. The system includes a reservoir of pressurized air and associated leveling valve that uses a relay valve to improve refill times when the vehicle returns from a dump mode operation to normal operation. The process reduces pressure in one or more of the axles when maneuvering the vehicle at predetermined slow speeds and maintaining that first predetermined pressure while the other axle(s) is at a greater pressure than the first axle. By preventing complete exhaustion of pressure from the suspension system, restoring air pressure is attained more quickly. Also, use of a relay valve enables higher flow rates to improve the refill time of the pneumatic suspension system after the dump operation.

Abstract: A vehicle brake system for a vehicle comprises at least one source of pressurized air for pressurizing the vehicle brake system, and a brake actuator configured to receive air from the source of pressurized air. A control is operatively associated with the source of pressurized air for selective application of the brake actuator. A supplemental parking brake control system is in communication with the control and the brake actuator. The control system is responsive to data indicative of gradient and speed vehicle conditions. The control system is configured to send a signal to the brake actuator to allow gradient and speed dependent supplemental parking. The control system is configured to prevent application of the brake actuator.

Abstract: A brake disabling device for a vehicle includes an electronic control unit (ECU) for receiving a signal indicative of a direction of the vehicle. A control device communicates with the ECU for disabling brakes associated with a steer axle of the vehicle as a function of the direction of the vehicle.

Abstract: A heavy vehicle trailer antilock braking system module includes a module control port receiving a pressure signal, a module exhaust port fluidly communicating with atmosphere, a first switching valve, a second switching valve, a relay valve, and control logic. The first switching valve includes an input port and an output port. The first switching valve input port fluidly communicates with the module control port. The second switching valve includes an input port and an output port. The second switching valve output port fluidly communicates with the module exhaust port. A relay valve includes a supply port, a delivery port, an exhaust port, and a control port. The relay valve control port fluidly communicates with the first switching valve output port and the second switching valve input port. The delivery port fluidly communicates with the supply port and the exhaust port as a function of a pressure signal at the relay valve control port.

Abstract: A pneumatic brake system for a heavy duty vehicle is provided. The heavy duty vehicle has at least one source of pressurized air for pressurizing the brake system, at least one spring brake chamber including a spring brake assembly, and at least one service brake chamber including a service brake assembly. The brake system includes a first control valve, a second control valve and a work brake system. The first control valve is in communication with the source of pressurized air. The first control valve delivers pressurized air to the spring brake chamber and exhausts pressurized air to atmosphere to activate the spring brake assembly when brake system pressure is reduced to a predetermined low trip brake system pressure. The second control valve is in communication with the source of pressurized air and selectively delivers pressurized air to the service brake chamber for application of the service brake assembly.

Abstract: A brake valve actuator (BVA) of a vehicle is controlled by an electronic control unit (ECU) to provide automatic traction control (ATC), roll stability (RS) and yaw stability (YS) functions for the vehicle, by actuating the dual brake valve without driver intervention. The ATC function is provided by making braking pressure available at the driven wheels only of the vehicle. This may be done by selectively controlling the modulators for the driven wheels and the non-driven wheels of the vehicle. The ATC function in this manner can be provided for a straight truck or bus, or for a tractor and trailer, without the need for an ATC solenoid. In another embodiment, a yaw control function is provided, without the need for ATC solenoids or for pressure sensors in the delivery lines. In yet another embodiment, yaw control benefits are provided with an additional sensor.

Abstract: A system and process for controlling vehicle loading on a multi-axle vehicle and improving maneuverability is disclosed. The system includes a reservoir of pressurized air and associated leveling valve that uses a relay valve to improve refill times when the vehicle returns from a dump mode operation to normal operation. The process reduces pressure in one or more of the axles when maneuvering the vehicle at predetermined slow speeds and maintaining that first predetermined pressure while the other axle(s) is at a greater pressure than the first axle. By preventing complete exhaustion of pressure from the suspension system, restoring air pressure is attained more quickly. Also, use of a relay valve enables higher flow rates to improve the refill time of the pneumatic suspension system after the dump operation.

Abstract: A module includes a reservoir having at least three chambers for storing compressed air for a vehicle air supply system, and a mounting assembly for supporting the reservoir on the vehicle. The chambers are separate from each other internally. The reservoir includes external connections, such as air lines or piping, for interconnecting the three chambers. The mounting assembly includes a bracket having a support surface. A bracket liner is received on the bracket between the support surface and the outer side surface of the reservoir. The reservoir may also include a purge chamber and an air dryer, as one unit, supported on the vehicle by the mounting assembly.

Abstract: An interrupt for an automatic traction control system includes a park brake control valve for controlling a park brake of a vehicle as a function of a park brake control pressure signal. A service brake control valve controls a service brake as a function of a service brake control pressure signal. A traction control valve communicates the service brake control pressure signal to the service brake control valve as a function of the park brake control pressure signal.

Abstract: A parking brake control circuit engages the parking brake of a vehicle when the transmission of the vehicle is in the “park” position and the engine of the vehicle is turned off, without requiring the constant application of electrical power. The parking brake control circuit utilizes latching solenoid technology that eliminates the need for a constant voltage source. A time-delay relay is used to change the state of the latching solenoid. The time-delay relay is preferably activated through a circuit containing an engine oil pressure switch, a transmission park switch and a vehicle speed switch. Activation of the relay latches the solenoid in a position that allows the parking brake to be applied, without requiring the application of a constant voltage to the solenoid. Accordingly, the possibility of inadvertent brake application due to electrical failure is avoided.

Abstract: A bus door/service brake interlock system having a warning system is provided. The interlock system includes a foot valve assembly to effect a service brake application when warning lights are activated, a vehicle door is open, and minimum speed conditions are met. An auxiliary line is positioned between a source of pressure and the foot valve assembly and includes a valve and a low pressure indicator. Should the operator leave the driver seat with the interlock system engaged, the parking brake is automatically applied.

Abstract: A cargo or bulk product off-load system includes a compressor (10) that pressurizes air. The air is dried by a dryer (12, 14) and routed to a supply tank (16). From the supply tank, the air is either used to pressurize service reservoirs (24, 26) or to assist the off-load system. Air stored in the service reservoirs (24, 26) is used to pressurize purge volumes associated with the dryers (12, 14). The compressor (10) operates at a lower pressure when supplying air to assist the off-load system than when pressurizing the service reservoirs (24, 26). Controllers (30, 40) coordinate switching of airflow, and alternating purging and drying of the dryers.