| 摘要 |
<p>The unit (1) comprises a basic rail (3), a center rail in the shape of a twin-T (5), and an end rail (7) which can be moved in relation to each other. A locking element (9) with a mainly curved outer contour and two flat segments is joined to the outer ends of the central rail (5) with a bolt (17) guided off center through the element (9). When the rails (3, 5, 7) are pulled into an extended or a contracted position the locking elements (9) are rotated around their off center axles (17) in order to release or to block the system (1).</p> |
