Patent ID: 8147141

Claim:
A linear motion guide unit; comprising an elongated guide rail having first raceway surfaces on a first side thereof and second raceway surfaces on a second side thereof extending in a lengthwise direction of the guide rail, and a slider allowed to move lengthwise of the elongated guide rail in a sliding manner, the slider being composed of a carriage having thereon third raceway surfaces in opposition to the first raceway surfaces and fourth raceway surfaces in opposition to the second raceway surfaces to define load-carrying races between the first and third raceway surfaces and the second and fourth raceway surfaces and having therein return passages extending in parallel with the load-carrying races, end caps secured to forward and aft ends of the carriage, one to each end, and made therein with turnaround passages joining the load-carrying races and the return passage together with one another, and a plurality of rolling elements allowed to roll through circulating circuits each of which is made up of each of the load-carrying race, return passage and the turnaround passages; wherein the slider has a plurality of flexible tubes lying in a lubricant inlet and oil grooves in the end cap to connect between the lubricant inlet and the circulating circuits in sidewise opposing bulgy portions of the slider, the plurality of flexible tubes being installed in the end cap to provide lubricant passages for lubricant delivered out of the lubricant inlet in the load-carrying race, wherein the circulating circuits are in pairs in each of the bulgy portions of the slider and the tubes are connected at distal ends thereof to three-way members, respectively, which are open to the turnaround passages of the circulating circuits, wherein the end caps are composed of end cap major parts to define curved outside halves of the turnaround passages and spacer parts that fit into the end cap major parts to define curved inside halves of the turnaround passages, and wherein the three-way members connected to the tubes are fitted in grooves in the spacer parts.