| 摘要 |
<p>The bed includes a track (22) fixed at the base (2); a slider means (30) is restrained to the guide means (20) with possibility of moving along the track (22); the slider means (30) is also restrained to a track (43) that is integral to the mobile element (10) with possibility of moving along the track (43); to the slider (30) is connected a means (50) able to supply a force (F) that determines the position and the movement of the slider (30) along the track (22); the tangent to the course followed by the slider (30) along the track (22) forms with the force (F) an angle that is smaller than a right angle and such that the projection of the force (F) on said tangent corresponds with the direction of movement that the mobile element (10) carries out to raise the upper structure (4). <IMAGE></p> |
