| 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. |
