Patent ID: 7950852
Filing Date: 2011-05-31
Classification: F16C

Abstract:
1. A linear motion guide unit; comprising an elongated guide rail having a first raceway surface on a side thereof extending in a lengthwise direction of the guide rail, and a slider fitting over and conforming to the guide rail to move lengthwise of the elongated guide rail in a sliding manner by virtue of more than one rolling element, the slider being composed of a carriage having thereon a second raceway surface in opposition to the first raceway surface of the guide rail to define a load-carrying race between them and having therein a return passage extending in parallel with the load-carrying race, end caps secured to forward and aft ends of the carriage, one to each end, and provided therein with turnaround passages joining the load-carrying race and the return passage together with one another, more than one rolling element allowed to roll through a circulating circuit made up of the load-carrying race, return passage and the turnaround passages, and an inside seal fitted to a downward surface inside a recess of the carriage in opposition to a top surface of the guide rail; wherein the inside seal is composed of a metallic core of flat metal sheet extending across an overall length of downward surfaces inside the recesses of the carriage and end caps, and a sealing member secured to the metallic core; wherein the metallic core is provided at forward and aft ends thereof with lugs, which extend at widthwise middles to come into engagement with their associated mating portions of the end caps to keep the inside seal in the end caps; wherein the sealing member includes a first lip coming into sliding engagement with one of widthwise opposing edges of the top surface of the guide rail to prevent foreign materials against creeping along the top surface of the guide rail into the load-carrying race, and a second lip extending sidewise to come into close engagement with an inward sidewall of the recess in the carriage to protect the load-carrying race against foreign materials, which creep along recessed surfaces inside the carriage; wherein the second lip extends in a direction opposite to the first lip to keep the first lip at a location to make certain of smooth sliding engagement with the top surface of the guide rail, and wherein the first and second lips lie on a common line in a way heading for directions opposite to one another, and wherein the first lip extends inward of the inside seal while the second lip heads outward.