| 摘要 |
<p>The inner rail (1) axially movable in an outer rail (8) of U-shaped cross-section comprises a part (2) of insulating material and a metal rack (6) secured in a groove (5) of the upper edge of the insulating part (2). The outer rail (8) is provided with longitudinal holes (12). A synthetic material guide (11) which is removably secured in each hole presents a longitudinal slot (13) and, on the bottom thereof, an enlarged recess (14). The inner rail (1) is guided and held by its insulating part (2) in the slot (13) of the guide (11) and by its enlarged part (10) in the enlarged recess (14) so that the inner rail (1) is longitudinally movable in the outer rail (8) but can not be disengaged from the top. The part of the inner rail (1) which projects from the outer rail (8) upwardly has approximately the same length as the outer rail (8) in order to prevent dust or impurities from getting into the slot (9) of the outer rail (8).</p> |
