Patent ID: 7341378

Claim:
A linear motion guide unit comprising an elongated guide rail having a lengthwise raceway surface thereon, and a slider movable lengthwise of the elongated guide rail, the slider being comprised of a carriage made therein with a second raceway surface in opposition to the first raceway surface and a return passage extending in parallel with a load race defined between the first and second raceway surfaces, end caps mounted on lengthwise opposite ends of the carriage and made therein with turnaround passages connecting the load race with the associated return passage, and more than one roller allowed to roll through a recirculating circuit composed of the load race, the return passage and the turnaround passage, wherein the end caps are each comprised of an end cap major body to make a radially outside curved surface of the turnaround passage and guide surfaces extending along widthwise opposite edges of the radially outside curved surface to make a sliding-contact with axially opposite ends of the roller, and a spacer having an outside surface to make a radially inside curved surface of the turnaround passage after having fitted into the end cap major body, the outside surface of the spacer having thereon some holes, which have functions of lubricant reservoirs, prevention of distortion caused in the molded spacer pieces, and ejector pinholes, and wherein the holes in the spacer are made circular in shape and indentical in their heading directions to be opposite against rolling surfaces of the rollers while they roll through the turnaround passage.