Hydraulic cylinder and biased wear ring assembly for use therein

A linear hydraulic cylinder of the type including a cylinder barrel, first closure means cooperating with said cylinder barrel to define a head end and a fluid inlet port, second closure means cooperating with said cylinder barrel to define a rod end and a fluid outlet port;

• a piston assembly reciprocally disposed within said cylinder barrel for movement over substantially the entire axial length of the cylinder barrel, said piston assembly including a piston cooperating with an interior, cylindrical surface of said cylinder barrel and said first and second closure means to define a head end fluid chamber and a rod end fluid chamber, said piston assembly further including a rod member fixed to said piston and extending through a rod opening in said second closure means;
• said piston including an outer, generally cylindrical surface closely spaced apart from said interior surface of said cylinder barrel, said outer cylindrical surface defining first and second annular grooves being disposed adjacent said head end and said rod end fluid chambers, respectively, a wear ring being disposed in said first annular groove, and a seal assembly being disposed in said second annular groove;
• characterized by:
• (a) said wear ring comprising a generally annular, split ring member defining a substantially cylindrical outer surface bounded by a pair of substantially square corners;
• and
• (b) a loader member disposed in said first annular groove and operable to bias said wear ring into sufficiently tight engagement with said interior, cylindrical surface of said cylinder barrel substantially to prevent passage of contaminant particles between said interior surface and said wear ring.