Patent ID: 7740406

Claim:
A linear motion guide system, comprising a guide rail made with a lengthwise raceway groove, a slider moving on the guide rail in a sliding manner by virtue of more than one roller, and a highly-tight sealing unit mounted on any one of forward and aft ends of the slider to come into close sliding-contact with lengthwise outward surfaces around the guide rail, making sure of highly sealing effect to keep any foreign matter away from entering inside the slider; wherein the highly-tight sealing unit is comprised of a cassette constituted by a front panel and an enclosure with the front panel at any one of edges thereof, sealing plates stowed in the cassette, at least one lubrication plate lying in close adjacency to the sealing plates to supply the sealing plates with lubricant; and a rear panel to close an open edge of the enclosure, the cassette having a locating pin planted on and protruding from the front panel thereof, wherein the sealing plates and the at least one lubrication plate are each made with a locating hole to fit over the locating pin on the front panel, wherein the sealing plates are each composed of a sheet of mechanical froth urethane foam of low foam ratio, which is formed by frothing mechanically a raw liquid mixed with air, the sheet having a three-layered structure composed of skin layers of rubbery texture to constitute epidermal layers and an intermediate medium of spongy texture lying between the epidermal layers, and the spongy texture medium being impregnated with lubricant, and wherein the lubrication plates have a sliding-contact edge that is allowed to come into a race formed on the guide rail, for applying the lubricant to the race on the guide rail.