| 摘要 |
The invention relates to a drive gear for a raisable and lowerable table, and having two cogged racks (2, 4) which are driven reciprocally in opposite directions by a gear wheel device (6) and a motor (8). The gear wheel device has at least two first gear wheels (10, 12) which are interconnected in order to rotate synchronously. The first gear wheels (10, 12) are disposed between the cogged racks for meshing with and driving thereof when the racks are wholly or partly displaced towards one another. <IMAGE> |
