Patent ID: 6129358
Filing Date: 2000-10-10
Classification: F16J,Y10S

Abstract:
A sealing ring for forming a unidirectionally sealed condition around a member axially movable in a bore of a hydraulic cylinder, the sealing ring comprising:an elastomeric ring member having an axially facing sealing face, an opposite axially facing pressure face, a circumferential radial outer surface, and a circumferential radial inner surface, the elastomeric ring member being cooperatively receivable in an annular groove around the bore of the hydraulic cylinder with the sealing face positioned in opposed relation to a first axial groove wall located in the groove and the pressure face positioned in opposed relation to an opposite second groove wall, the sealing face having at least two continuous annular beads therearound of small radial extent positioned for sealably engaging the first axial groove wall, the radial inner surface having a radially inner most circumferential lip of small axial extent positioned for sealably engaging the member axially movable in the bore, the pressure face and the radial outer surface including at least one passage thereacross communicating the bore with the sealing face, andwherein when the elastomeric ring member is cooperatively received in the groove around the bore of the hydraulic cylinder and the groove is of greater axial extent than the elastomeric ring member a pressure condition in the bore of the hydraulic cylinder acting against the pressure face greater than a pressure condition in the bore acting against the sealing face is operable to urge the elastomeric ring member towards the first groove wall to sealably engage the at least two sealing beads with the first groove wall and a pressure condition in the bore acting against the pressure face less than a pressure condition in the bore acting against the sealing face is operable to urge the elastomeric ring member away from the first groove wall to allow fluid in the bore to flow between the at least two sealing beads and the first groove wall and through the at least one passage communicating the pressure face with the sealing face.