Radial piston machine and piston for a radial piston machine of this type

Patent metadata

Field	Value
Publication number	US-9556866-B2
Application number	US-201113811543-A
Country	US
Kind code	B2
Filing date	Jun 22, 2011
Priority date	Jul 23, 2010
Publication date	Jan 31, 2017
Grant date	Jan 31, 2017

Abstract

A radial piston machine includes a piston having a base which is provided with a roller. The roller is held secure by a bearing shell that is inserted in the piston base.

First claim

The invention claimed is:

1. A radial piston machine comprising:
a housing;
a rotatably mounted cylinder star;
a stroke ring which is fixed with respect to the housing; and
a multiplicity of pistons supported on the stroke ring and guided in the rotatably mounted cylinder star,
wherein each piston of the multiplicity of pistons has a roller which is rotatably mounted on a piston foot via a bearing shell,
wherein a captive retention mechanism for the roller is formed by the bearing shell,
wherein a receptacle on the piston foot extends around the bearing shell over no more than 180°, and
wherein the bearing shell extends around the roller over a circumferential angle of greater than 180°, such that a portion of the bearing shell is unsupported by the piston foot.

2. The radial piston machine as claimed in claim 1 , wherein the bearing shell is fastened to the piston foot by a rivet.

3. The radial piston machine as claimed in claim 2 , wherein the rivet is a blind rivet.

4. The radial piston machine as claimed in claim 2 , wherein the rivet has a passage duct configured to supply fluid to a bearing region.

5. The radial piston machine as claimed in patent claim 4 , wherein:
for each piston of the multiplicity of pistons the passage duct opens to a bore of each corresponding piston of the multiplicity of pistons, and
the bore has a pressure medium connection to high pressure.

6. The radial piston machine as claimed in claim 4 , wherein a hydrostatic field is formed in the bearing shell in a region of the passage duct.

7. A radial piston machine, comprising:
a housing;
a rotatably mounted cylinder star;
a stroke ring which is fixed with respect to the housing; and
a multiplicity of pistons supported on the stroke ring and guided in the rotatably mounted cylinder star, wherein:
each piston of the multiplicity of pistons has a roller which is rotatably mounted on a piston foot via a bearing shell;
a captive retention mechanism for the roller is formed substantially by the bearing shell; wherein the bearing shell is connected to the piston foot by adhesive bonding and riveting; wherein the bearing shell extends around the roller over a circumferential angle of greater than 180, such that a portion of the bearing shell is unsupported by the piston foot.

8. A piston for a radial piston machine, comprising:
a piston foot defining a receptacle;
a bearing shell partially received by the receptacle;
a roller mounted on the bearing shell; and
a captive retention mechanism for the roller formed by the bearing shell,
wherein the receptacle extends around the bearing shell over no more than 180°, and
wherein the bearing shell extends around the roller over a circumferential angle of greater than 180°, such that a portion of the bearing shell is unsupported by the piston foot.

9. The piston as claimed in claim 8 , wherein the bearing shell is fastened to the piston foot by a rivet.

10. The piston as claimed in claim 9 , wherein the rivet is a blind rivet.

11. The piston as claimed in claim 9 , wherein the bearing shell is fastened to the piston foot by adhesive bonding and a rivet.

12. The piston as claimed in claim 9 , wherein the rivet has a passage duct configured to supply fluid to a bearing region of the bearing shell.

13. The piston as claimed in claim 12 , wherein:
the passage duct opens to a bore of the piston, and
the bore has a pressure medium connection to high pressure.

14. The piston machine as claimed in claim 12 , wherein a hydrostatic field is formed in the bearing shell in a region of the passage duct.

Assignees

• Breuer David
• Bosch Gmbh Robert

Inventors

• Breuer David

Classifications

• F04B1/0408

  Pistons · CPC title

• F04B1/0439

  Supporting or guiding means for the pistons · CPC title

• F04B1/0435

  Arrangements for disconnecting the pistons from the actuated cam · CPC title

• F04C2/00 Primary

  Rotary-piston machines or pumps (with non-parallel axes of co-operating members F04C3/00; with the working-chamber walls at least partly resiliently deformable F04C5/00; with fluid ring or the like F04C7/00; rotary-piston pumps specially adapted for elastic fluids F04C18/00; rotary-piston machines or pumps in which the working-fluid is exclusively displaced by, or exclusively displaces, one or more reciprocating pistons F04B) · CPC title

• F04B27/0442

  Supporting and guiding means for the pistons · CPC title