High-pressure sealing ring

Abstract

A high-pressure sealing ring for hydraulic assemblies has a substantially—“L”—shaped body with a leg and foot, where an external heel-portion is designed to provide a “rolling” line of sealing contact with the seat in the cylinder or piston in which it is seated.

1 . A sealing ring for use in a hydraulic assembly of the type having a piston slidably received in a cylinder, the sealing ring including:
 an annular ring body of “substantially L” cross-section, with a leg portion and a foot portion interconnected by an external heel having a curved profile.   
     
     
         2 . A sealing ring as claimed in  claim 1 , wherein:
 the external heel has a convex profile to form a “rolling” line of sealing contact with a seat in a cylinder or piston to which the ring body is installed.   
     
     
         3 . A sealing ring as claimed in  claim 1 , wherein;
 the leg has a sealing protrusion intermediate an outer sealing face of the leg, the sealing protrusion having a cylindrical sealing face interposed between a pair of inclined ramp faces, the sealing protrusion and a distal portion of outer sealing face forming two lines of sealing contact between the ring body and an adjacent cylinder or piston to which the ring body is installed.   
     
     
         4 . A sealing ring as claimed in  claim 1 , wherein:
 the foot has a toe portion with a relief angle a in the range of 1 ° to 5° relative to the central axis of the ring body.   
     
     
         5 . A sealing ring as claimed in  claim 1 , wherein:
 the toe portion engages a wall portion of a piston or cylinder associated with the cylinder or piston in which the sealing ring is installed, and the toe portion is moved towards full sealing contact with the wall portion as the heel rolls in the seat as hydraulic pressure between the cylinder and piston is increased.   
     
     
         6 . A sealing ring as claimed in  claim 1 , wherein:
 The sealing ring has a protrusion on an outer sealing surface of the leg, or the external heel, receivable in a recess in the cylinder or piston in which the sealing ring is seated.