Patent ID: 7481150
Filing Date: 2009-01-27
Classification: F15B

Abstract:
1. A fluid cylinder comprising: a cylinder housing defining a bore that extends in an axial direction; an extensible member that moves between a retracted position and an extended position within the bore of the cylinder housing, the extensible member including a sealing member that defines a plurality of grooves; a plurality of metallic sealing rings, each ring being located within a corresponding groove in the sealing member, each ring defining a gap along a circumference of each ring, the rings being positioned in the grooves so that the gaps in the rings are in a staggered arrangement in the axial direction to form a liquid seal between the sealing member and the surface of the bore; a metal alloy coating covering at least an inside surface of the bore, the metal alloy coating reducing the coefficient of friction of the inside surface; and at least one fluid passage for receiving a fluid and wherein, when fluid is forced into the fluid passage, the extensible member moves to the extended position.