Patent ID: 8888367

Claim:
A linear motion guide unit; comprising an elongated guide rail having two sides, each side having a pair of first raceway surfaces extending lengthwise of the guide rail, and a slider that fits over or conforms to the elongated rail for movement in a sliding manner relative to the elongated guide rail; wherein the slider has a carriage, a pair of end caps, end seals, porous compacts, and a plurality of rolling element, the carriage having a pair of second raceway surfaces extending in opposition to the pair of first raceway surfaces on the guide rail to provide a pair of load-carrying races between the pair of first raceway surfaces and the pair of second raceway surfaces, and a pair of return passages extending along the pair of load-carrying races, the end caps being fastened on forward and aft end surfaces of the carriage, one to each end surface, and provided therein with turnaround passages to join together the pair of load-carrying races and the pair of return passages, the end seals being attached on outward end surfaces of the end caps, the porous compacts being impregnated with lubricant and installed in concavities in the end caps to open to the end seals, and the rolling elements being allowed to roll through circulating circuits made up of the pair of load-carrying races, the pair of return passages and the turnaround passages, and in doing so make rolling contact with the porous compacts at the turnaround passages to be applied with the lubricant; and wherein each of the end caps has an end surface facing on the end surface of the carriage and having lubricating grooves reaching the turnaround passages and a first lubricating hole extending across the end cap in a sliding direction of the slider to communicate with the lubricating grooves, and each of the end seals has a second lubricating hole lying in alignment with the first lubricating hole and extending across the end seal, the second lubricating hole being smaller in diameter than the first lubricating hole, but allowing an applicator needle for lubricant to pierce through the second lubricating hole, whereby the lubricant supplied from the applicator needle through the second lubricating hole in the end seal, after having gone through the first lubricating hole, is resupplied from the lubricating grooves to the turnaround passages to lubricate the rolling elements and the lubricant is resupplied to the porous compact which is in part exposed to the first lubricating hole so that the lubricant is applied to the rolling elements through the porous compact at the turnaround passages.