Sleeve valve oil seal

Abstract

Leakage of a liquid (e.g. a coolant and/or a lubricant) past a sleeve valve to a port in communication with a combustion chamber of an internal combustion engine can be prevented by use of a substantially ring-shaped seal, which can be carried on the sleeve valve or disposed on a stationary part of the internal combustion engine.

What is claimed: 
     
         1 . A sleeve valve assembly comprising:
 a sleeve valve having a valve body configured to at least partially encircle one or more pistons that moves in a reciprocating manner on operation of an internal combustion engine, the sleeve valve and the one or more pistons at least partially defining a combustion chamber of the internal combustion engine, the sleeve valve being configured to move between open and closed positions to control fluid flow through a port that opens to the combustion chamber; and   a substantially ring-shaped seal configured to resist leakage of a liquid comprising coolant and/or lubricant past the valve body to the port, the substantially ring-shaped seal comprising at least one of:   a) a ring carried in a groove recessed into the valve body, and   b) first and second rings disposed around the valve body and biased apart from each other, the first and second rings being disposed on a stationary part of the internal combustion engine such that the valve body moves relative to the first and second rings.   
     
     
         2 . The sleeve valve assembly of  claim 1 , wherein the ring and/or each of the first and second rings is formed of a metal. 
     
     
         3 . The sleeve valve assembly of  claim 1 , further comprising one or more compression rings for resisting leakage of gases in the combustion chamber and/or the port past the sleeve valve. 
     
     
         4 . The sleeve valve assembly of  claim 1 , wherein the sleeve valve reciprocates between the open and closed positions along a common axis with a piston of the one or more pistons. 
     
     
         5 . The sleeve valve assembly of  claim 1 , wherein the substantially ring-shaped seal comprises the ring carried in the groove recessed into the valve body, and wherein the seal exerts a radial force outward against the stationary part of the internal combustion engine. 
     
     
         6 . The sleeve valve assembly of  claim 5 , wherein the seal exerts a first force against a first side of the groove and a second force against a second side of the groove. 
     
     
         7 . The sleeve valve assembly of  claim 6 , wherein the seal comprises a biasing structure that exerts the first and second forces. 
     
     
         8 . The sleeve valve assembly of  claim 5 , wherein the seal comprises both the ring and an additional ring, and the ring and additional ring are substantially flat, split rings. 
     
     
         9 . The sleeve valve assembly of  claim 8 , wherein the ring and the additional ring are separated by the biasing structure. 
     
     
         10 . The sleeve valve assembly of  claim 5 , wherein the groove is configured such that the material thickness of the valve body is substantially the same at the groove as through a remainder of the valve body. 
     
     
         11 . The sleeve valve assembly of  claim 5 , wherein the seal remains substantially stationary relative to the valve body as the sleeve valve moves. 
     
     
         12 . The sleeve valve assembly of  claim 1 , wherein the substantially ring-shaped seal comprises the first and second rings disposed on the stationary part and around the valve body, and wherein the first and second rings have respective ring tensions to exert a radial force inward against the valve body. 
     
     
         13 . The sleeve valve assembly of  claim 12 , wherein the first ring and the second ring are separated by a biasing structure which biases them apart. 
     
     
         14 . The sleeve valve assembly of  claim 12 , wherein the first and second rings comprise flat, split rings having respective ring tensions arising from one or more of their shape;
 size; curvature and material.   
     
     
         15 . The sleeve valve assembly of  claim 12 , wherein the stationary part comprises a groove in which the seal is installed and wherein the first ring is biased against a first side of the groove and the second ring is biased against a second, opposite side of the groove. 
     
     
         16 . The sleeve valve assembly of  claim 15 , wherein the stationary part further comprises an oil drain through which oil in the groove drains. 
     
     
         17 . A method comprising:
 moving a sleeve valve between open and closed positions to control fluid flow through a port of an internal combustion; and   resisting leakage of a liquid comprising coolant and/or lubricant past a valve body of the sleeve valve to the port, the resisting being performed at least in part by a substantially ring-shaped seal comprising at least one of:   a) a ring carried in a groove recessed into the valve body, and   b) first and second rings disposed around the valve body and biased apart from each other, the first and second rings being disposed on a stationary part of the internal combustion engine such that the valve body moves relative to the first and second rings.   
     
     
         18 . The method of  claim 17 , further comprising resisting leakage of gas past the sleeve valve. 
     
     
         19 . The method of  claim 17 , wherein the sleeve valve reciprocates between the open and closed positions along a common axis with a piston of the one or more pistons. 
     
     
         20 . The method of any of  claim 17 , wherein the substantially ring-shaped seal comprises the ring carried in the groove recessed into the valve body, and wherein the seal exerts a radial force outward against the stationary part of the internal combustion engine. 
     
     
         21 . The method of any of  claim 17 , wherein the substantially ring-shaped seal comprises the first and second rings disposed on the stationary part and around the valve body, and wherein the first and second rings have respective ring tensions to exert a radial force inward against the valve body. 
     
     
         22 . The method of  claim 21 , further comprising draining liquid out of a groove in the stationary part in which the seal is disposed.