Hydraulic radial piston device

Patent metadata

Field	Value
Publication number	US-11448203-B2
Application number	US-201715694101-A
Country	US
Kind code	B2
Filing date	Sep 1, 2017
Priority date	Sep 9, 2016
Publication date	Sep 20, 2022
Grant date	Sep 20, 2022

Abstract

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

First claim

What is claimed is:

1. A hydraulic radial piston device comprising:
a housing;
a pintle attached to the housing and having a pintle shaft, the pintle having a fluid inlet end and an opposite fluid outlet end;
a rotor mounted on the pintle shaft and configured to rotate relative to the pintle shaft about a rotor axis of rotation, the rotor having a plurality of cylinders;
a plurality of pistons, each being displaceable in each of the plurality of cylinders;
a piston ring disposed around the rotor and having a piston ring axis of rotation, the piston ring configured to rotate about the piston ring axis of rotation as the rotor rotates relative to the pintle shaft about the rotor axis of rotation; and
a drive shaft rotatably supported within the housing and rotatable with the rotor;
wherein the pintle includes an integrated bearing surface for supporting rotation of the rotor either directly or by an intermediate fluid, wherein the pintle includes a lubrication groove defined though the integrated bearing surface and configured to feed hydraulic fluid for lubricating the integrated bearing surface, wherein the lubrication groove includes a first pintle lubrication groove that extends through the integrated bearing surface at an exterior of the pintle between the fluid inlet end of the pintle and one of a rotor inlet communication port and a rotor outlet communication port, wherein the lubrication groove includes a second pintle lubrication groove that extends through the integrated bearing surface at the exterior of the pintle between the fluid outlet end of the pintle and one of the rotor inlet communication port and the rotor outlet communication port, the integrated bearing surface integrally formed to surround the rotor inlet communication port and the rotor outlet communication port except for at the first and second lubrication grooves, the rotor inlet communication port formed on the pintle shaft and configured to be selectively in fluid communication with the plurality of cylinders, and the rotor outlet communication port formed on the pintle shaft and configured to be selectively in fluid communication with the plurality of cylinders;
wherein the first and second pintle lubrication grooves extend axially along a length of the pintle.

2. The radial piston device of claim 1 , wherein the pintle includes a pintle wall extending at least partially along a pintle inlet channel defined by the pintle shaft.

3. The radial piston device of claim 2 , wherein the pintle wall is configured to separate the pintle inlet channel into two sections.

4. The radial piston device of claim 1 , wherein the pintle includes an inlet recess being depressed from the integrated bearing surface and the rotor inlet communication port is defined on the inlet recess.

5. The radial piston device of claim 4 , wherein the pintle includes an outlet recess being depressed from the integrated bearing surface and the rotor outlet communication port is defined on the outlet recess.

6. The radial piston device of claim 5 , wherein the pintle includes a timing recess configured to adjust timing of fluid communication between the rotor outlet communication port and the plurality of cylinders.

7. The radial piston device of claim 6 , wherein the timing recess includes a first outlet timing recess and a second outlet timing recess, the first and second outlet timing recesses formed on the pintle shaft and abutted to opposite sides of the outlet recess, respectively, so as to be in fluid communication with the rotor outlet communication port through the outlet recess.

8. The radial piston device of claim 5 , wherein the first and second pintle lubrication grooves each extend to the inlet recess.

9. The radial piston device of claim 4 , wherein the pintle includes a timing recess configured to adjust timing of fluid communication between the rotor inlet communication port and the plurality of cylinders.

10. The radial piston device of claim 9 , wherein the timing recess includes a first inlet timing recess and a second inlet timing recess, the first and second inlet timing recesses formed on the pintle shaft and abutted to opposite sides of the inlet recess, respectively, so as to be in fluid communication with the rotor inlet communication port through the inlet recess.

11. The radial piston device of claim 1 , wherein the plurality of cylinders of the rotor are arranged in a plurality of rows of cylinders, the rows extending about the rotor axis of rotation, and each row of cylinders including a pair of radially oriented cylinders, the rotor further including:
a plurality of rotor fluid ports, each rotor fluid port being in fluid communication with the pair of radially oriented cylinders and being alternatively in fluid communication with either the rotor inlet communication port of the pintle shaft or the rotor outlet communication port of the pintle shaft;
wherein each rotor fluid port includes a first rotor port channel connected to one cylinder of the pair of radially oriented cylinders and a second rotor port channel connected to the other cylinder of the pair of radially oriented cylinders, the first rotor port channel and the second rotor port channel being formed by cross-drilling.

12. The radial piston device of claim 1 , wherein the plurality of cylinders of the rotor are arranged in a plurality of rows of cylinders, the rows extending about the rotor axis of rotation, the rotor further including:
at least one flat face arranged adjacent at least one of the plurality of rows of cylinders and extending axially on an outer surface of the rotor to include openings of the at least one of the plurality of rows of cylinders.

13. The radial piston device of claim 1 , wherein the piston ring has a V-shape configuration on an inner diameter thereof.

14. The radial piston device of claim 13 , wherein the piston ring has an inner diameter and an outer diameter, the inner diameter and the outer diameter axially extending between opposite axial end faces, the inner diameter having a first radius measured around the piston ring axis at a fillet point of the piston ring and a second radius measured around the piston ring axis at the axial end faces, the first radius being greater than the second radius.

15. The radial piston device of claim 1 , wherein the piston ring has an inner diameter and an outer diameter, the inner diameter and the outer diameter axially extending between opposite axial end faces, the piston ring including:
one or more radially extending grooves formed on at least one of the axial end faces between the inner diameter and the outer diameter and configured to enable hydraulic fluid to travel between the inner diameter and the outer diameter.

16. The radial piston device of claim 1 , wherein the drive shaft has a driving end and a power transfer end, the drive shaft including a shaft body at the driving end and a power transfer flange at the power transfer end, the power transfer flange configured to be connected to the rotor and defining a flow passage being in fluid communication with a pintle inlet channel of the pintle shaft, wherein the drive shaft includes a crossbar provided to the power transfer flange, the crossbar extending across the flow passage and being offset from a base of the power transfer flange.

17. The radial piston device of claim 1 , wherein the drive shaft includes at least one engagement element provided on a power transfer flange, and the rotor includes at least one engagement element provided on an inlet end of the rotor.

18. The radial piston device of

Assignees

• Eaton Intelligent Power Ltd

Inventors

• Smith Aaron
• Bawdhankar Sushant Subhash
• Davis Aaron Matthew
• Skinner Jeffrey David
• Gibson Kendrick Michael
• Long Mark Alan
• Hansen Nicholas John
• Lee Kendall Otis

Classifications

• F04B1/066

  by changing the phase relationship between the actuating cam and the distributing means · CPC title

• F04B1/07

  by varying the relative eccentricity between two members, e.g. a cam and a drive shaft · CPC title

• F04B53/18

  Lubricating · CPC title

• F03C1/046

  by changing the excentricity of one element relative to another element · CPC title

• F03C1/0472

  with cam-actuated distribution members · CPC title