Also disclosed is a corresponding hydraulic drive in an open circuit with a constant pump (1') or an adjustable pump (1'').

The variable pump also comprises regulating blocks (5) and a feed control assembly.

The plurality of hydraulic pumps comprises a first variable pump for driving a first execution mechanism.

When the variable pump is used as an oil pump of the engine, the waste of the engine feed oil is reduced and the economic efficiency of the engine is increased.

An engine with the variable pump and an automobile with the engine are also disclosed.

A variable pump or motor is provided including a housing (1, 2) with inlet and outlet ports (17-23) and a vaned rotor (15).

The variable pump assembly may be configured to control an output water pressure as a function of the irrigation assembly's location or position.

It is best not to use a variable pump to avoid the dynamic response characteristics of the variable mechanism affecting the test results.

The first pump is a variable displacement hydraulic pump.

variable displacement piston type pump

variable delivery piston type pump

A variable delivery pump is employed as the pilot pump.

At least the second hydraulic pump is a variable displacement bidirectional pump.

The variable capacity pump may be a variable displacement pump and the system may also include an electric displacement control adapted to control displacement of the variable displacement pump.

variable displacement pump with pressure compensator