Piston Ring for Reduction of Crevice Volume
AssigneeLiquidPiston, Inc.
InventorsNikolay Shkolnik, Alexander Shkolnik
Life of this patent
Estimating the term…
Abstract
Embodiments of a piston ring reduce the volume of a crevice defined between the circumferential wall of a cylinder and a portion of the outer wall of a piston within the cylinder, the portion extending down from the top of the piston. The piston ring is configured such that pressurized fluid within the cylinder reliably urges a radial face of the piston ring to sealingly engage the circumferential wall of the cylinder, even as the piston reciprocates within the cylinder.
Claims16
A piston ring for sealing a gap between a circumferential surface of a piston (150) of a reciprocating machine and a wall (111) of a cylinder of the machine within which the piston reciprocates along an axis, the piston ring comprising:
- an upper member (210) configured to reside in a peripheral corner cut-out (153) of the piston, the upper member having:
- (i) a radial contact surface (211) configured to be radially loaded against the cylinder wall (111) during operation of the reciprocating machine,
- (ii) at least one fluid-pressure receiving surface (212, 213), and
- (iii) an inner axial contact surface (214) configured to contact a ridge (170) of the piston, when the at least one fluid-pressure receiving surface (212 and 213) is axially loaded by fluid pressure;
- wherein the radial contact surface and the at least one fluid-pressure receiving surface are shaped so that the fluid pressure causes a net force by which the radial contact surface is urged radially against the cylinder wall and the inner axial contact surface is urged axially against the piston.
A piston ring for sealing a gap between a circumferential surface of a piston (150) of a reciprocating machine and a wall (111) of a cylinder of the machine within which the piston reciprocates along an axis, the piston ring comprising:
- a circumferential member (210) configured to reside in a peripheral corner cut-out (153) of the piston, the circumferential member having:
- (i) a radial contact surface (211) configured to be radially loaded against the cylinder wall (111) during operation of the reciprocating machine, and
- (ii) at least one fluid-pressure receiving surface (212, 213)
- wherein a projection (293) of the at least one fluid-pressure receiving surface (212, 213) onto the wall of the cylinder is greater than a projection (291) of the radial contact surface (211) onto the wall of the cylinder.
A piston ring for sealing a gap between a circumferential surface of a piston (150) of a reciprocating machine and a wall of a cylinder (110) of the machine within which the piston reciprocates along an axis, the piston ring comprising:
- means for substantially filling a crevice between a top region of the piston and the wall (111) of the cylinder, and having
- (i) a radial contact surface (211), and
- (ii) at least one fluid-pressure receiving surface (212, 213);
- and
- means for securing the piston ring in a peripheral corner cut-out of the piston;
- wherein the radial contact surface and the at least one fluid-pressure receiving surface are shaped so that fluid pressure causes a net force by which the radial contact surface is urged radially against the cylinder wall.
A piston ring for sealing a gap between a circumferential surface of a piston (150) of a reciprocating machine and a wall (111) of a cylinder of the machine within which the piston reciprocates along an axis, the piston ring comprising:
- an upper member (210) configured to reside in a cut-out of the piston, the upper member having:
- (i) a radial contact surface (211) configured to be radially loaded against the cylinder wall (111) during operation of the reciprocating machine,
- (ii) at least one fluid-pressure receiving surface (212, 213), and
- (iii) an inner axial contact surface (214) configured to contact a ridge (170) of the piston, when the at least one fluid-pressure receiving surface (212 and 213) is axially loaded by fluid pressure;
- a bridge spanning an axial distance downwardly from the upper member;
- and
- a secondary seal disposed radially inward from the bridge,
- wherein the radial contact surface and the at least one fluid-pressure receiving surface are shaped so that the fluid pressure causes a net force by which the radial contact surface is urged radially against the cylinder wall and the inner axial contact surface is urged axially against the piston, and the secondary seal is configured to be loaded against the piston or the bridge by pressure of any fluid that has blown by the inner axial contact surface.
Dependencies are inferred from the claim text.