Hydraulic pump
AssigneeNabtesco Corporation
InventorToshiya AKAMI
Life of this patent
Estimating the term…
Abstract
One object is to provide a hydraulic pump that allows a drive source to be started with a small torque. The hydraulic pump includes: a cylinder block having a plurality of cylinder bores and disposed so as to be rotatable; pistons each retained in associated one of the cylinder bores so as to be movable; a swash plate for controlling the amount of movement of the pistons in accordance with the size of the tilt angle; a first pressing unit for pressing the swash plate in such a direction as to reduce the tilt angle of the swash plate; and a second pressing unit for pressing the swash plate in such a direction as to increase the tilt angle of the swash plate by the pressure supplied from the outside.
Claims10
A hydraulic pump comprising:
- a cylinder block having a plurality of cylinder bores and disposed so as to be rotatable;
- a plurality of pistons each retained in an associated one of the plurality of cylinder bores so as to be movable;
- a swash plate configured to control an amount of movement of the plurality of pistons in accordance with a size of a tilt angle of the swash plate;
- a first pressing unit configured to press the swash plate only by the elastic force of at least one spring in a tilt angle reducing direction so as to reduce the tilt angle of the swash plate;
- and
- a second pressing unit configured to press the swash plate in a tilt angle increasing direction so as to increase the tilt angle of the swash plate by a pressure supplied from outside of the hydraulic pump,
- wherein the pressure is a pressure corresponding to a load-sensing flow control pressure, a pressure corresponding to a positive flow control pressure or a pressure corresponding to a lock lever pressure.
Dependencies are inferred from the claim text.