High pressure pump systems with reduced pressure ripple for use with waterjet systems and other systems are described herein. A pump system configured in accordance with a particular embodiment includes four reciprocating members operably coupled to a crankshaft at 90 degree phase angles. The reciprocating members can include plungers operably disposed in corresponding cylinders and configured to compress fluid (e.g., water) in the cylinders to pressures suitable for waterjet processing, such as pressures exceeding 30,000 psi.

High pressure pump systems with reduced pressure ripple for use with waterjet systems and other systems are described herein. A pump system configured in accordance with a particular embodiment includes four reciprocating members operably coupled to a crankshaft at 90 degree phase angles. The reciprocating members can include plungers operably disposed in corresponding cylinders and configured to compress fluid (e.g., water) in the cylinders to pressures suitable for waterjet processing, such as pressures exceeding 30,000 psi.

Displacement control device for variably adjusting the displacement of an axial piston hydraulic pump including a rotary shaft rotatable around a shaft axis. A torque can be applied for rotating the rotary shaft to open and close servo pressure lines to adjust the displacement volume of the axial piston hydraulic pump. Concentric to the shaft axis in a mid-portion of the rotary shaft a detent sleeve is positioned having an abutment area onto which, in the neutral position, a sliding element abuts. The detent sleeve, in operating conditions is rotatably fixed with the rotary shaft and turns with the rotary shaft and for neutral position adjustments in non-operating conditions, the detent sleeve and the rotary shaft are detachable from each other such that the rotary shaft can be turned relative and independently within the detent sleeve, which is held in its neutral position by the sliding element.

A variable flow hydraulic device having a plurality of cylinders for varying a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid to said each cylinder; a first output port of the housing connected to said each cylinder, the first output port facilitating the ejection of the hydraulic fluid from said each cylinder, the first output port configured for fluidly coupling said each cylinder to the load; a respective flow control valve for said each cylinder, and a fluid pressure sensing device coupled between downstream of the first output port and said respective flow control valve.

A variable flow hydraulic device having a plurality of cylinders for varying a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid to said each cylinder; a first output port of the housing connected to said each cylinder, the first output port facilitating the ejection of the hydraulic fluid from said each cylinder, the first output port configured for fluidly coupling said each cylinder to the load; a respective flow control valve for said each cylinder, and a fluid pressure sensing device coupled between downstream of the first output port and said respective flow control valve.

The present invention relates to an inline piston pump, comprising a driveshaft for driving the inline piston pump; at least two pistons which are operatively connected to the driveshaft and are disposed along a driveshaft axis and are in each case disposed so as to be movable in a reciprocating manner in a piston chamber; a suction connector for supplying a fluid to be pumped; wherein a suction valve is disposed in at least one, preferably in each, piston chamber in order to fluidically separate a suction duct for the inflow of fluid from the piston chamber during a compression movement of the associated piston.

The pump is characterized in that a suction throttle valve which is conceived for varying a volumetric flow of a fluid to be pumped between the suction chamber and the suction duct is provided between the suction connector and the suction duct which in fluidic terms is connected directly to the at least one valve.

A hydrostatic system that provides different volumetric efficiency at different states and includes a pump with a discharge and supply line. Connected between the discharge and supply line is a valve. The valve is adapted to move to a position having a cross port orifice when the pump is in a neutral state and a position where the ports are blocked when the pump is in an operation state.

An electric torque and pressure control for load sensing pumps includes a variable open circuit pump with a swash plate angle sensor. The pump is connected in line with a pressure compensated load sensing control having an electrically variable pressure relief valve and orifice. Connected to the circuit is an engine speed sensor, a user input device, and a micro-controller. The micro-controller has software that controls a pressure relief setting of the electrically variable pressure relief valve in the pressure sensing control based upon signals from the swash plate sensor and the engine speed sensor and inputs from the user input device.

A hydrostatic system that provides different volumetric efficiency at different states and includes a pump with a discharge and supply line. Connected between the discharge and supply line is a valve. The valve is adapted to move to a position having a cross port orifice when the pump is in a neutral state and a position where the ports are blocked when the pump is in an operation state.

A fuel pump includes a mechanical regulating valve arranged in a pump body which modulates the pressure in a high pressure space so that the pressure matches the engine demand. Modulation by the regulating valve requires adjustment of the inlet fuel quantity, adjustment of the volume of the high pressure space, and control of a return fluid communication enabling fuel to exit the high pressure reservoir.