| 摘要 |
The screw-scissors-type jack arm (1, 2) is provided at its ends with openings for fasteners for rotatable connection with the other arm (1, 2) and the base (4) or the upper plate (5) of the screw-scissors-type jack. The arm (1, 2) is made of filled polymers. The center of gravity of the arm (1, 2) cross section areas lies in vertical longitudinal plane of the arm (1, 2) symmetry, on the trace of the plane with a plane comprising axes of opening for the fasteners or at a distance of at least four millimeters from that trace. |
