Abstract: A variable capacity hydraulic machine has a rotating group located within a casing and a control housing secured to the casing to extend across and seal an opening in the casing. The control housing accommodates a control circuit and a pair of sensors to sense change in parameters associated with the rotating group. One of the sensors is positioned adjacent the barrel on the rotating group to sense rotational speed and the other senses displacement of the swashplate. The control housing accommodates a control valve and accumulator to supply fluid to the control valve.

Abstract: Multiple hydraulic machines are located in a common housing. The swashplates are located in longitudinal bores and the barrels in transverse bores. Valve housings are located on either side to accommodate control valves and circuitry. The barrels are mechanically coupled by a gear train for conjoint rotation.

Abstract: A rotary hydraulic machine has a swashplate adjustable by an actuator. The swashplate has a part cylindrical bearing surface supported by a complimentary bearing surface in the housing and a fluid bearing acts between the surfaces. The fluid is supplied to the fluid bearing by pressure compensated flow control valves to maintain a predetermined flow of fluid. The actuator includes a pair of single acting hydraulic motors secured in the housing and acting on the swashplate at spaced locations. The pistons of the hydraulic motors engage cylindrical pins located on the swashplate to permit a rolling motion between the swashplate and motors as the swashplate is adjusted.

Abstract: A variable capacity hydraulic machine has a rotating group located within a casing and a control housing secured to the casing to extend across and seal an opening in the casing. The control housing accommodates a control circuit and a pair of sensors to sense change in parameters associated with the rotating group. One of the sensors is positioned adjacent the barrel on the rotating group to sense rotational speed and the other senses displacement of the swashplate. The control housing accommodates a control valve and accumulator to supply fluid to the control valve.

Abstract: A hydraulic drive system for an actuator uses a pair of pressure compensated hydraulic machines to control flow to and from the drive chambers of the actuator by varying the controlled pressure of one of the machines. The machines are mechanically coupled to permit energy recovery and charge an accumulator to store supplies energy. The drive system may be combined with other services including a transmission for incorporation in a vehicle. The transmission uses a pressure compensated supply and torque control of the wheels.

Abstract: Multiple hydraulic machines are located in a common housing. The swashplates are located in longitudinal bores and the barrels in transverse bores. Valve housings are located on either side to accommodate control valves and circuitry. The barrels are mechanically coupled by a gear train for conjoint rotation.

Abstract: An actuator has a position encoder provided by a helical groove formed in the piston rod. The groove is filled with a material of different magnetic characteristics to provide a smooth exterior surface and a varying discernible signal as the rod moves relative to the cylinder. An array of Hall effect sensors is provided around the rod to provide phase shifted signals as the rod moves so that the signal of one sensor may be correlated by the signals of other sensors.

Abstract: A variable capacity hydraulic machine has a rotating group located within a casing and a control housing secured to the casing to extend across and seal an opening in the casing. The control housing accommodates a control circuit and a pair of sensors to sense change in parameters associated with the rotating group. One of the sensors is positioned adjacent the barrel on the rotating group to sense rotational speed and the other senses displacement of the swashplate. The control housing accommodates a control valve and accumulator to supply fluid to the control valve.

Abstract: A piston assembly for a hydraulic machine is formed with a part spherical cavity in the piston to receive a spherical bearing of a slipper assembly. The spherical bearing is secured in the cavity by swaging the walls of the piston and subsequently working the wall to provide a clearance to allow relative rotation.

Abstract: A variable capacity hydraulic machine has a rotating group located within a casing and a control housing secured to the casing to extend across and seal an opening in the casing. The control housing accommodates a control circuit and a pair of sensors to sense change in parameters associated with the rotating group. One of the sensors is positioned adjacent the barrel on the rotating group to sense rotational speed and the other senses displacement of the swashplate. The control housing accommodates a control valve and accumulator to supply fluid to the control valve.

Abstract: A hydraulic machine-has a rotating group located within a housing and a port plate to control flow from the barrel of the rotating group to inlet and outlet ports. The port plate is sealed against one of the housing or barrel and sleeves extend between the other of the housing or barrel to accommodate misalignment between the barrel and housing as the barrel rotates.

Abstract: A rotary hydraulic machine has a swashplate adjustable by an actuator. The swashplate has a part cylindrical bearing surface supported by a complimentary bearing surface in the housing and a fluid bearing acts between the surfaces. The fluid is supplied to the fluid bearing by pressure compensated flow control valves to maintain a predetermined flow of fluid. The actuator includes a pair of single acting hydraulic motors secured in the housing and acting on the swashplate at spaced locations. The pistons of the hydraulic motors engage cylindrical pins located on the swashplate to permit a rolling motion between the swashplate and motors as the swashplate is adjusted.

Abstract: A hydraulic motor comprising a housing having a fluid inlet. A fluid outlet and a cavity there between, a pair of intermeshing gear elements rotatable in the housing about mutually parallel axes. Each of the gear elements having a set of gear teeth disposed about the periphery of the element and a support shaft extending from oppositely directed end faces of the set of gear teeth. A bearing assembly located on opposite sides of the cavity in said housing to support the shafts for rotation about respective ones of the axes. Each of the bearing assemblies having a sealing face overlying the end faces and biased into engage with the end faced by a pressure compensating seal located between the bearing and the housing. The sealing face having a channel extending partially about the spindle and in fluid communication with the inlet to introduce fluid under pressure between the faces.

Abstract: A hydraulic motor comprising a housing having a fluid inlet. A fluid outlet and a cavity there between, a pair of intermeshing gear elements rotatable in the housing about mutually parallel axes. Each of the gear elements having a set of gear teeth disposed about the periphery of the element and a support shaft extending from oppositely directed end faces of the set of gear teeth. A bearing assembly located on opposite sides of the cavity in said housing to support the shafts for rotation about respective ones of the axes. Each of the bearing assemblies having a sealing face overlying the end faces and biased into engage with the end faced by a pressure compensating seal located between the bearing and the housing. The sealing face having a channel extending partially about the spindle and in fluid communication with the inlet to introduce fluid under pressure between the faces.

Abstract: An actuator has a position encoder provided by a helical groove formed in the piston rod. The groove is filled with a material of different magnetic characteristics to provide a smooth exterior surface and a varying discernible signal as the rod moves relative to the cylinder. An array of Hall effect sensors is provided around the rod to provide phase shifted signals as the rod moves so that the signal of one sensor may be correlated by the signals of other sensors.

Abstract: An actuator has a position encoder provided by a piston rod having a body of magnetic material progressively tapering from one end to another in a direction of relative movement between the piston rod and a cylinder. The piston rod has a coating of non-magnetic material, providing a smooth, uniform exterior surface. An array of Hall effect sensors is mounted in a support located in and radially movable relative to an end cap fixed to the cylinder.

Abstract: An electromagnetic actuator has an armature assembly including a pair of spaced plate springs to locate the magnetic core radially. The springs are formed from concentric rings interconnected by radial bridges so that flexure of the spring does not cause radial displacement. A single coil or double coil may be used and each coil is supported on a pair of bobbins. One bobbin overlies the core and the other has a recess to receive part of the core to maintain a uniform air gap between the core and bobbin.

Abstract: A flow transducer includes a piston movable in a sleeve to vary the area of an orifice. The piston may move in either direction from a position in which flow is prevented. Movement in both directions is opposed by a spring. The piston assumes a unique position for each flow rate and the position of the transducer is sensed to provide a signal indicative of low rate.

Abstract: A hydraulic valve includes a spool movable within a body to regulate flow across the valve. Movement of the spool is controlled by an electromagnetic actuator that operates either directly or through a pilot stage upon the spool. When operating through a pilot stage, the actuator varies pilot pressure by an operating member co-operating with an orifice. A flapper valve may be used to vary a pair of pilot flows in complementary manner. Feedback signals of pressure and spool position are provided to a controller which selectively combines the signals to monitor the operating parameters of the valve. The controller may modify the position signal with the pressure signal to obtain an indication of flow rate through the valve.

Abstract: A turbo compounder includes an exhaust driven turbine (19) to supply compressed gas to the engine intake (17a). A transmission (23) that includes a variable ratio transmission element transfers energy between the turbine (19) and an engine derived energy reserve (27). A controller (16) adjusts the ratio of the transmission to manage the energy transfer by monitoring a predetermined operating parameter of the engine (10).