| 摘要 |
A support structure (10), preferably a rotatable bed, pivotable between a generally horizontal use position and a generally vertical storage position is disclosed. A counterbalancing mechanism (20) which reduces the amount of force needed to rotate the support structure (10) is operatively connected to the support structure (10). A drive arm (70) driven by a motor mechanism (64) in a linear direction is also operatively connected to the support structure (10). The drive arm (70) is connected to the support structure (10) through a linkage apparatus. The linkage apparatus has linkage plates (82) pivotably connected to drive arm (70) and connecting plates (92) extending from the support structure (10). A T-shaped rod mechanism (102) is engaged by latch (116), rotatably connected to the linkage plates (82), and extends through a hole in frame member (14) of support structure (10) where a coil spring (124) is received about the rod mechanism (102). The support structure (10) may be power rotated or manually rotated depending on whether the latch (116) is engaged or disengaged, respectively. Coil spring (124) allows movement of the support structure (10) relative to the drive arm (70) if an extraordinary force acts on the support structure (10). |
