A linear guide bearing apparatus has a guide rail including a first raceway groove;
a movable element including a second raceway groove and a rolling element return
groove connected continuously with the second raceway groove through curved grooves
respectively formed in the two end portions of the second raceway groove, the movable
element being movably fitted with the guide rail; a plurality of rolling elements
loaded in a circulation passage including the first raceway groove, the second
raceway groove, the curved grooves, and the rolling element return groove for moving
the movable element along the guide rail; and, an under-seal disposed in the movable
element for sealing a space between the guide rail and the movable element, wherein
the under-seal includes a sliding contact portion elastically contacted with the
guide rail to thereby receive an upward-going force from the guide rail.
