Caterpillar Sarl

Adam Adeeb

Steven Edward Johnson

Umakanth Sakaray

Ernest Everett Stoops

Josh Nolke

John J Kaufman

Neil Taylor

Roger Tansley

John Chapman

Tony Maughan

Anthony Joseph Weltzer

Samantha L Sergott

Steven Johnson

Two cooling fans acting on different heat exchangers may be driven via parallel circuits from a variable displacement hydraulic pump. At least one of the circuits includes a two position valve operable by a control system to vary the flow resistance of the circuit to share the flow between the two fan motors responsive to the relative heat load on the heat exchangers. The pump displacement is controlled to provide a constant hydraulic output pressure irrespective of the operational state of the or each valve assembly.

Flow sharing control for multiple hydraulic fan motors

The present invention pertains to a brake system for a vehicle, in particular a wheeled vehicle, comprising a control unit configured to operate the brake system in an automatic retarding control mode and in a brake assist mode, a brake pedal valve, and at least one brake valve unit for actuating a brake actuator. The break valve unit comprises a brake valve for applying pressurized fluid to the brake actuator in response to a control pressure applied to a hydraulic actuator of the brake valve, a blocking valve for controlling application of pressurized fluid from the brake pedal valve to the hydraulic actuator of the brake valve, and a brake pressure control valve for controlling application of pressurized fluid to the hydraulic actuator of the brake valve.

Brake system for a vehicle

A first valve module () includes a valve block and circuits for controlling hydraulic pressure to parking brake and differential lock actuation circuits of a vehicle. An extension flowpath () has an extension inlet and outlet opening respectively through an interface surface and further external surface of the valve block. A second module () may be connected to supply a first service brake circuit, the circuits of the first module, and, via a second service brake outlet communicating with the extension inlet, a second service brake circuit. In a method, first and second valve blocks with internal flowpaths formed respectively by machining and by casting are assembled together with valves to define valve modules () having respective, first and second functional circuits. The first valve block includes an extension flowpath. The second module supplies pressure to the first functional circuit and the extension flowpath of the first module.

Hydraulic valve module and method for supplying hydraulic pressure to circuits of a vehicle

A system for delivering fluid in a machine is provided. The system includes a pump, a first valve disposed downstream of the pump, a check valve disposed downstream of the first valve, at least one accumulator disposed downstream of the check valve, and an auxiliary system disposed upstream of the check valve. The system further includes a control unit configured to receive a signal indicative of a fluid demand from the auxiliary system. The control unit is also configured to selectively control the first valve in a first position to limit flow of the fluid from the pump to the auxiliary system, and in a second position to allow flow of the fluid from the pump to the auxiliary system based, at least in part, on the received signal. The check valve limits flow of a fluid from the at least one accumulator to the auxiliary system.

Fluid delivery system

A hydraulic valve module () for a vehicle () is configured to receive hydraulic pressure from a first pump () via a first pump inlet () in a first interface surface when connected to a first adjacent module (), and from a second pump () via an external port (). The module () combines both flows to supply a work function circuit () of a vehicle via a port () formed in a second interface surface to communicate with a second adjacent module (). The module () prioritises flow from the second pump () to a steering circuit () over the work function circuit, and restricts flow from the first pump () to the work function circuit to prioritise and maintain pressure in the first adjacent module upstream of the first pump inlet () which may supply service brake and cooling fan circuits () of the vehicle.

Hydraulic valve module for steering and work functions in a work vehicle

A hydraulic valve assembly for a work vehicle includes a fan and brake function module. A first pump supplies hydraulic pressure to a fan circuit and to first and second service brake circuits of the vehicle. A second pump supplies hydraulic pressure to a steering and work function module that in turn supplies hydraulic pressure to a steering circuit and a work function circuit of the vehicle. The hydraulic valve assembly may also include a work control module and an auxiliary module. The modules of the hydraulic valve assembly are separably connected together via interface surfaces.

Modular hydraulic valve assembly for work vehicle

A hydraulic system for a vehicle in which the first and second brake valves are arranged in a parallel configuration. The pressure inlet of the first and second brake valves are connected to a source of hydraulic fluid and the exhaust outlets of the first and second brake valves are connected to the first and second brakes, respectively. The control inlets of the first and second brake valves are directly responsive to a braking signal from an operator of the vehicle. First and second control valves are configured to selectively provide hydraulic fluid to the control inlet of the first and second brake valves, respectively.

Hydraulic system for brakes

An accumulator pressure monitoring system for monitoring pressure in a hydraulic circuit. The accumulator includes a first chamber filled with a gas, a second chamber filled with a liquid and a movable separator disposed between the first and second chambers. A pressure sensor measures the pressure in the first chamber; and a control unit receives pressure readings from the pressure sensor and compares the pressure readings to threshold pressure values and may control the accumulator based upon this comparison.

Accumulator pressure monitoring system

Braking system includes a brake, first valve that actuates the brake based on user input, second valve configured to selectively actuate the brake, and valve actuation system including a user input device moveable between first and second positions. A brake sensor provides a signal indicative of actuation of the first valve. The valve actuation system activates the second valve if the user input device is in the first position and the first valve engaged, retaining the second valve in active state if the first valve is disengaged, deactivating the second valve if the user input device is in the second position.

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Seaham, United Kingdom

Adam Adeeb