Inline piston pump

Patent metadata

Field	Value
Publication number	US-2022018340-A1
Application number	US-202117374358-A
Country	US
Kind code	A1
Filing date	Jul 13, 2021
Priority date	Jul 15, 2020
Publication date	Jan 20, 2022
Grant date	—

Abstract

An inline piston pump that is efficient, manufacturable, and durable. The angled bearing surface within the pump that it contacts drives the piston and rotates with the cylinder.

First claim

What is claimed is:

1 . An axial piston device comprising:
a housing including a first end portion and a second end portion and including a low-pressure fluid inlet and a high-pressure fluid outlet at the first end portion of the housing; a cylinder block rotatably positioned within the housing including a first end portion and a second end portion, the first end portion of the cylinder block being in the first end portion of the housing and the second end portion of the cylinder block being in the second end portion of the housing, the cylinder block including a plurality of cylindrical bores that extend from the first end portion to the second end portion of the cylinder block; a drive shaft including a first end portion that extends inside of the housing and is configured to drive the rotation of the cylinder block within the housing, the drive shaft defining a cylinder block axis of rotation; a plurality of pistons, each piston including a first end portion and a second end portion, each piston being positioned within a cylindrical bore such that the piston can reciprocate within the cylindrical bore axially along a longitudinal axis of the piston, the first end portion of the pistons being positioned in the first end portion of the cylinder block, and the second end portion of the pistons extending out of the second end portion of the cylinder block; and an angled yoke assembly located in the second end portion of the housing, the yoke assembly being inclined relative to a plane that is perpendicular to the cylinder block axis of rotation, the yoke assembly including a bearing surface configured to contact the second end portions of the plurality of pistons, wherein the bearing surface of the yoke assembly is configured to rotate about a yoke assembly axis of rotation synchronously with the cylinder block.

2 . The axial piston device of claim 1 , wherein the yoke assembly axis of rotation intersects with a bearing surface plane that is coincident with the bearing surface at a bearing plate central point, wherein the bearing plate central point is offset from the intersection point between the yoke assembly axis of rotation and the cylinder block axis of rotation, wherein the offset is in the direction of the second end portion of the housing along the yoke assembly axis of rotation, and wherein the bearing plate central point is offset from the cylinder block axis of rotation.

3 . The axial piston device of claim 1 , further comprising a retainer configured to engage the second end portions of the pistons and limit the axial motion of the pistons, wherein the retainer is a plate that includes an aperture of which the pistons extend through, the retainer being bolted to the yoke assembly.

4 . The axial piston device of claim 1 , wherein the yoke assembly includes an angled plate that rotates on a bearing assembly and a bearing plate that interfaces with the angled plate.

5 . The axial piston device of claim 1 , wherein the second end portion of the pistons includes a conical head portion that defines an annular retaining collar.

6 . The axial piston device of claim 1 , wherein the axial piston device is a hydraulic pump.

7 . An axial piston device comprising:
a housing including a first end portion and a second end portion and including a low-pressure fluid inlet and a high-pressure fluid outlet at the first end portion of the housing; a cylinder block rotatably positioned within the housing including a first end portion and a second end portion, the first end portion of the cylinder block being in the first end portion of the housing and the second end portion of the cylinder block being in the second end portion of the housing, the cylinder block including a plurality of cylindrical bores that extend from the first end portion to the second end portion of the cylinder block; a drive shaft including a first end portion that extends inside of the housing and is configured to drive the rotation of the cylinder block within the housing, the drive shaft defining a cylinder block axis of rotation; a plurality of pistons, each piston including a first end portion and a second end portion, each piston being positioned within a cylindrical bore such that the piston can reciprocate within the cylindrical bore axially along the longitudinal axis of the piston, the first end portion of the pistons being positioned in the first end portion of the cylinder block, and the second end portion of the pistons extending out of the second end portion of the cylinder block; an angled plate located in the second end portion of the housing, the angled plate being inclined relative to a plane that is perpendicular to the cylinder block axis of rotation; a bearing assembly provided between the angled plate and the second end portion of the housing enabling the angled plate to rotate about an angled plate axis of rotation; a bearing plate secured to the angled plate, the bearing plate configured to contact with the second end portion of the plurality of pistons; a retainer configured to engage the second end portions of the pistons and limit the axial motion of the pistons; and wherein the angled plate, the bearing plate, and the retainer are configured to rotate synchronously with the cylinder block.

8 . The axial piston device of claim 7 , wherein the retainer is a plate that includes an aperture of which the pistons extend through, the retainer being fixed to the angled plate.

9 . The axial piston device of claim 7 , wherein the bearing plate is retained by the angled plate.

10 . The axial piston device of claim 7 , further comprising a pin that limits relative rotation between the bearing plate and the angled plate.

11 . The axial piston device of claim 7 , wherein the second end portion of the piston includes a conical shape.

12 . The axial piston device of claim 7 , wherein the second end portion of the piston includes a conical shape wherein the face of the cone defines a curved profile.

13 . The axial piston device of claim 7 , wherein the second end portion of the piston includes an annular collar that engages the retainer.

14 . The axial piston device of claim 7 , wherein the second end portions of the piston are configured to trace elliptical circles on the bearing plate.

15 . The axial piston device of claim 7 , wherein the angle of the angled plate is fixed.

16 . The axial piston device of claim 7 , wherein the rotational speed of the drive shaft varies in order to vary the flow of the pump.

17 . The axial piston device of claim 7 , wherein the second end portion of the piston translates radially relative to the bearing plate when the cylinder block rotates.

18 . The axial piston device of claim 7 , wherein the intersection of the projection of the cylinder block axis of rotation and the projection of the angled plate axis of rotation is within the planes defined by a top surface of the retainer and a bottom surface of the retainer.

19 . The axial piston device of claim 7 , wherein the angled plate axis of rotation intersects with a bearing surface plane coincident with an exposed face of the bearing plate at a bearing plate central point that is offset from the intersection point between the angled plate axis of rotation and the cylinder block axis of rotation, wherein the offset is in the direction of the second end portion of the housing along the angled plate axis of rotation.

20 . The axial piston device of claim 7 , wherein the angled plate axis of rotation intersects with a be

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Ghosh Arindam
• Devan Stephen Marshall
• Valtr Kelly Dale
• Shand Charles Andrew
• Datta Sauradeep

Classifications

• F04B1/20

  having rotary cylinder block · CPC title

• F04B1/2085 Primary

  Bearings for swash plates or driving axles · CPC title

• F04B1/2092 Primary

  Means for connecting rotating cylinder barrels and rotating inclined swash plates · CPC title

• F04B1/2028 Primary

  Bearings · CPC title