| 摘要 |
A bed/trolley (1) comprises a platform (8) supported by telescopic columns (14) housing scissor link mechanisms. Two matching threaded nuts (33, 34) are mounted to each half of a lead screw (31) driven by a motor (15), and to the support arms (16a, 16b) of the scissor link mechanism. The lead screw (31) has one half threaded as a right-hand thread and the other half threaded as a left-hand thread. As the lead screw (31) is rotated one way the nuts (33, 34) are driven apart extending the scissor link mechanism, and when rotated in the opposite direction, the nuts (33, 34) are driven toward one another, retracting the scissor link mechanism. The columns (14) consists of scissor link fixing brackets (21, 26) and a central cover (28) which slide within each other, providing a very low height when the scissor mechanism is retracted. |
