Abstract: A hydraulic flow control valve assembly comprises an inlet port for input fluid flow from a pump, a first outlet port for output fluid flow to a power steering unit, a second-outlet port for output fluid flow to an accumulator of a braking system, and an excess flow port for output fluid flow to other services or a tank. A flow control valve controls the fluid flow from the inlet port to the outlet ports and the excess flow port, and a load sensing port communicates a load-dependent pressure signal from the power steering unit to the valve so as to provide priority fluid flow to the power steering unit. A pilot valve is provided for cutting off the load-dependent pressure signal when the pressure within the accumulator falls below a predetermined value so as to provide for fluid flow from the valve to the accumulator, and in addition a pressure difference sensing arrangement communicates the pressure difference across a restrictor to the valve so as to provide fluid flow to the accumulator.

Abstract: A hydrostatic transmission for a vehicle, such as a commercial walk-behind mower, comprises a fixed displacement pump, first and second reversible hydraulic motors for driving first and second ground engageable wheels, respectively, of the vehicle, and first and second spool valves for controlling hydraulic fluid flow from the fixed displacement hydraulic pump to the first and second hydraulic motors, respectively. The transmission may have a further fixed displacement hydraulic pump arranged in tandem with the first mentioned pump, a fluid pressure operated device and a third spool valve movable between a first position in which hydraulic fluid from the further pump is supplied to the pressure operated device and a second position in which hydraulic fluid from the further pump is supplied to the first and second spool valves to supplement hydraulic fluid from the first mentioned hydraulic pump.

Abstract: A rotary positive-displacement fluid-pressure motor which includes a casing, having an inlet port and an outlet port, at least two intermeshing rotors of toothed or lobed form housed for rotation in the casing, and means for conducting pressure fluid derived from the inlet port as far as a predetermined position in a face adjacent, and engaged by, a side of one of the rotors. A recess is so disposed in that face intermediate the predetermined position and the outlet port that, for facilitating starting of the motor when fluid under high pressure is directed into the inlet port, some of that fluid can gain access to the recess by way of said means and whichever intertooth or interlobe space of that rotor is so positioned as to place the means and the recess in communication.