Fluid pressure pump and fluid pressure system
AssigneeNabtesco Corporation
InventorsMasahiko Maruoka, Atsushi Fukui
Life of this patent
Estimating the term…
Abstract
A fluid pressure pump and a fluid pressure system in which leakage of fluid and ablation of a cylinder block and a port plate can be prevented by pressing the cylinder block to the port plate with an appropriate pressing force. A hydraulic pump includes a cylinder block that has a cylinder chamber that may be in communication with an oil passage of a port plate and in which a piston is housed; and a cylinder block pressing means imparting, to the cylinder block, a pressing force that presses the cylinder block to the port plate. The cylinder block pressing mechanism has a changing means that changes the force that presses the cylinder block to the port plate.
Claims11
A fluid pressure pump, comprising:
- a port plate in which a fluid passage is formed;
- a cylinder block including a cylinder chamber in which a piston is housed, wherein the cylinder chamber is in communication with the fluid passage in the port plate;
- and
- a pressing means configured to apply a pressing force to the cylinder block, the pressing force configured to press the cylinder block to the port plate, and
- a swash plate specifying movement of the piston in a rotational axis direction of the cylinder block,
- wherein the pressing means comprises:
- a changing means configured to change the pressing force, and
- a piston pressing means configured to press the piston to the swash plate and a cylinder block pressing means that presses the cylinder block to the port plate,
- wherein the cylinder block pressing means is disposed at a distance from the rotational axis, the distance being larger than a distance between the piston pressing means and the rotational axis,
- wherein the changing means is provided in the cylinder block pressing means,
- wherein the cylinder block pressing means is operated by a fluid pressure, and
- wherein the changing means is configured to decrease the pressing force that presses the cylinder block to the port plate as the fluid pressure supplied to the cylinder block pressing means increases.
A fluid pressure pump, comprising:
- a cylinder block including a central axis and a cylinder chamber in which a piston is housed;
- a port plate coaxially coupled to the cylinder block, the port plate including a fluid passage communicated with cylinder chamber;
- a first biasing member configured to bias the cylinder block to the port plate in a first axial direction;
- a biasing force adjuster configured to dynamically control biasing force of the first biasing member;
- and
- a second biasing member configured to bias the piston in a second axial direction opposite to the first axial direction,
- wherein the biasing force adjuster includes an introducing oil passage configured to supply a hydraulic fluid to displace the first biasing member in a second axial direction opposite to the first axial direction to dynamically control the biasing force of the first biasing member.
Dependencies are inferred from the claim text.