Piston ring unit and compressor
AssigneeKabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)
InventorsToru OKADA, Tomohiro OTSUKA
Life of this patent
Estimating the term…
Abstract
The piston ring unit includes a plurality of piston rings and an inner contact ring. A plurality of piston rings are disposed adjacent to each other in an axial direction of the piston such that joints of plurality of the piston rings do not overlap with each other in the axial direction. An inner contact ring is interposed between an outer circumferential surface of the piston and an inner circumferential surface of the piston ring in a state where the inner contact ring extends over all of the plurality of piston rings in the axial direction, and is disposed such that an opening of the inner contact ring does not overlap with the joint of the at least one piston ring as viewed in a radial direction of the piston.
Claims18
A piston ring unit mounted on an outer circumferential surface of a piston which performs a reciprocating motion in a cylinder in a cylinder axis direction of the cylinder, the piston ring unit comprising:
- a plurality of piston rings each having a C-shape with a joint at a portion of each of the plurality of piston rings in a circumferential direction, the plurality of piston rings being mounted on the outer circumferential surface of the piston in a state where the plurality of piston rings are disposed adjacent to each other in an axial direction of the piston, and mount on an inner circumferential surface of the cylinder;
- and
- an inner contact ring having a C-shape as viewed in the axial direction with an opening in a portion of the inner contact ring in the circumferential direction, the inner contact ring being interposed between the outer circumferential surface of the piston and inner circumferential surfaces of the plurality of piston rings in contact with an inner circumferential surface of at least one of the plurality of piston rings,
- wherein
- the plurality of piston rings are disposed adjacent to each other in the axial direction such that the joints of the plurality of piston rings do not overlap with each other in the axial direction, and
- the inner contact ring is disposed over all of the plurality of piston rings in the axial direction, and is disposed such that the opening does not overlap with the joint of the at least one piston ring as viewed in a radial direction of the piston.
A piston ring unit mounted on a piston which performs a reciprocating motion in a cylinder in a cylinder axis direction of the cylinder, wherein
- the piston has an annular groove which is recessed inwardly in a radial direction and is formed annularly in a circumferential direction,
- the piston ring unit comprising:
- a plurality of piston rings each having a C-shape with an joint at a portion of each of the plurality of piston rings in a circumferential direction, the plurality of piston rings being mounted on a groove bottom surface of the annular groove of the piston in a state where the plurality of piston rings are disposed adjacent to each other in an axial direction of the piston, mount on an inner circumferential surface of the cylinder;
- and
- an inner contact ring having a C-shape as viewed in the axial direction with an opening in a portion of the inner contact ring in the circumferential direction, the inner contact ring being interposed between the groove bottom surface of the piston and an inner circumferential surface of at least one piston ring among the plurality of piston rings and in contact with the inner circumferential surface of the at least one piston ring,
- wherein
- the plurality of piston rings are disposed adjacent to each other in the axial direction such that the joints of the plurality of piston rings do not overlap with each other in the axial direction ,
- the inner contact ring is disposed over the at least one piston ring in the axial direction, and is disposed such that the opening does not overlap with all joints of the at least one piston ring as viewed in a radial direction of the piston,
- in a state where a side at which a pressure boosting chamber is foil led in the cylinder is set as a high-pressure side and a side opposite to the high-pressure side is set as a low-pressure side in the axial direction, the at least one piston ring is disposed closer to the low-pressure side than remaining piston rings in the plurality of piston rings, and an inner diameter of the at least one piston ring is set larger than an inner diameter of the piston ring adjacent to the at least one piston ring on the high-pressure side, and
- the inner contact ring is configured such that an end surface of the inner contact ring on the high-pressure side in contacts with or closes to the piston ring disposed adjacent to the high-pressure side, and an end surface of the inner contact ring on the low-pressure side in contacts with or closes to a groove side surface of the annular groove.
Dependencies are inferred from the claim text.