Abstract: Disclosed is an electro-hydraulic relay valve and corresponding valve assembly for a SAHR brake. First actuators are arranged to act on a first end of a floating valve spool and second actuators are arranged to act on a second end of the valve spool. One of the second actuators can receive hydraulic pressure from a pilot valve. In a first valve position, the pressure supply port communicates with the working port and the tank port is closed. In a second valve position, the pressure supply port is closed and communicates via a first sense line with one of the first actuators, the working port directs pressure to the tank port, the tank port communicates via a second sense line with another of the first actuators, and the working port communicates via a third sense line with one of the second actuators. In a central position, all three ports are closed.

Abstract: The present disclosure relates to a dual brake valve (10) configured to actuate two brakes of a vehicle. The dual brake valve (10) comprises a pressure input (13), a first brake pressure output (26) for actuating a first brake (104) and a second brake pressure output (46) for actuating a second brake (106). The dual brake valve (10) further comprises a first valve (24) fluidly connected to the pressure input (13) and configured to pressurize the first brake pressure output (26). The dual brake valve further comprises a second valve (44) fluidly connected to the pressure input (13) and configured to pressurize the second brake pressure output (46). The dual brake valve further comprises a pressure balancing passage (16) configured to bidirectionally fluidly connect the first valve (24) and the second valve (44) to balance a pressure between the first brake pressure output and the second brake pressure output.

Abstract: A valve assembly is provided. The valve assembly includes a valve body defining a bore. The valve assembly further includes a plunger adjacent the valve body. The valve assembly further includes a modulating biasing member abutting the plunger. The valve assembly further includes a spool disposed in the bore and adjacent the plunger with the modulating biasing member disposed therebetween. The plunger is configured to move the spool between a neutral position and an energized position. The spool defines a socket. The valve assembly further includes a piston disposed in the socket and configured to move between a first piston position and a second piston position within the socket.

Abstract: An improved electrohydraulic brake valve with overpressure protection is provided. The electrohydraulic brake valve includes an integrated pressure limiting device coupled to a modulating valve and a solenoid assembly. The pressure limiting device transmits an axial force from the solenoid plunger to the valve spool up to a set limit, which corresponds to a maximum output pressure. Above this set limit, a pre-loaded spring within the pressure limiting device compresses, thereby isolating further travel of the solenoid plunger from the valve spool. The pressure limiting device mechanically limits the output pressure of the electrohydraulic brake valve to a maximum level to prevent overpressure in the brake system, adding a level of safety not previously available.

Abstract: Disclosed is an electrohydraulic valve that includes a pressure reducing valve in a single monoblock valve body. In one example, the valve is a reverse modulating valve with a body having an output port (B), a pressure supply port (P), and a tank port (T). The electrohydraulic valve is configured as a spool valve having a return spring, a feedback pin, and a proportional solenoid, where the proportional solenoid is arranged to oppose the return spring and feedback pin. An externally adjustable pressure reducing valve is between the pressure supply port (P) and the electrohydraulic spool valve. Above a current threshold, increasing current to the solenoid proportionally reduces pressure at the output port (B). Examples of a braking system incorporating the valve are also disclosed.

Abstract: An externally adjustable pressure modulating valve is disclosed. In one example, the valve has a valve body extending along a valve axis and defining a plunger cavity extending axially into a first end of the valve body. A valve spool is retained in the valve body and is movable along the valve axis. An input plunger is slidable axially in the plunger cavity between a resting position and an actuated position. An external adjustment mechanism is configured to adjust the modulation spring force when the input plunger is fully actuated. In one example, the adjustment mechanism includes a threaded sleeve in the plunger cavity, where rotating the threaded sleeve changes the mechanical stop of the input plunger.

Abstract: A dual orifice component has a plug with a unitary body that defines a central axis and has opposite axial ends. First and second holes are aligned along the central axis and each has first and second axially opposite ends. A third hole extends perpendicular to the central axis and passes through the plug. The first end of the first axial hole is located at one axial end of the plug, and the second end of the first axial hole communicates with and is open to the third hole. The first end of the second axial hole is located at the other axial end of the plug, and the second end of the second axial hole communicates with and is open to the third hole such that the first and the second holes are axially separated from each other by the third hole.

Abstract: Disclosed is an electro-hydraulic relay valve and corresponding valve assembly for a SAHR brake. First actuators are arranged to act on a first end of a floating valve spool and second actuators are arranged to act on a second end of the valve spool. One of the second actuators can receive hydraulic pressure from a pilot valve. In a first valve position, the pressure supply port communicates with the working port and the tank port is closed. In a second valve position, the pressure supply port is closed and communicates via a first sense line with one of the first actuators, the working port directs pressure to the tank port, the tank port communicates via a second sense line with another of the first actuators, and the working port communicates via a third sense line with one of the second actuators. In a central position, all three ports are closed.

Abstract: An improved electrohydraulic brake valve with overpressure protection is provided. The electrohydraulic brake valve includes an integrated pressure limiting device coupled to a modulating valve and a solenoid assembly. The pressure limiting device transmits an axial force from the solenoid plunger to the valve spool up to a set limit, which corresponds to a maximum output pressure. Above this set limit, a pre-loaded spring within the pressure limiting device compresses, thereby isolating further travel of the solenoid plunger from the valve spool. The pressure limiting device mechanically limits the output pressure of the electrohydraulic brake valve to a maximum level to prevent overpressure in the brake system, adding a level of safety not previously available.

Abstract: A valve assembly is provided. The valve assembly includes a valve body defining a bore. The valve assembly further includes a pull rod disposed in the bore and defining a bolt cavity. The pull rod is moveable between a first pull rod position and a second pull rod position. The valve assembly further includes a bolt disposed in the bolt cavity and moveable with respect to the pull rod between a first bolt position and a second bolt position. The valve assembly further includes a spool disposed in the bore. The spool is operatively coupled to the pull rod to move between an energized position and a neutral position.

Abstract: A valve assembly is provided. The valve assembly includes a valve body defining a bore. The valve assembly further includes a linear actuator adjoined to the valve body. The valve assembly further includes a spool disposed in the bore and operatively coupled to the linear actuator. The linear actuator is configured to move the spool between a neutral position and an energized position. The spool defines a socket. The valve assembly further includes a piston disposed in the socket and configured to move between a first piston position and a second piston position within the socket.

Abstract: A valve assembly is provided. The valve assembly includes a valve body defining a bore. The valve assembly further includes a plunger adjacent the valve body. The valve assembly further includes a modulating biasing member abutting the plunger. The valve assembly further includes a spool disposed in the bore and adjacent the plunger with the modulating biasing member disposed therebetween. The plunger is configured to move the spool between a neutral position and an energized position. The spool defines a socket. The valve assembly further includes a piston disposed in the socket and configured to move between a first piston position and a second piston position within the socket.

Abstract: A valve assembly is provided. The valve assembly includes a valve body defining a bore. The valve assembly further includes a pull rod disposed in the bore and defining a bolt cavity. The pull rod is moveable between a first pull rod position and a second pull rod position. The valve assembly further includes a bolt disposed in the bolt cavity and moveable with respect to the pull rod between a first bolt position and a second bolt position. The valve assembly further includes a spool disposed in the bore. The spool is operatively coupled to the pull rod to move between an energized position and a neutral position.