| 摘要 |
A load lifting device comprises a lower structure (2), an upper structure (3) movable with respect to the lower structure between a lowered position and a raised position, a scissors-like pantograph, comprising at least two arms (5, 6) mutually articulated according to a X-shape, connecting the upper structure (3) to the lower structure (2), and an actuator device (19) controlling the position of a connecting element (22) which connects the actuator (19) to one arm (5) of the pantograph and having a cam-following element (26) cooperating with a fixed cam (28). The actuator (19) is articulated to the connecting element (22) around an axis (21) which is located below the articulation axis (23) of the connecting element (22) to the arm (5) of the pantograph, in such a way that, when the actuator (19) is activated to cause the lifting movement of the device, the connecting element (22) acts as a pushing strut subjected substantially to compression between the cam (28) and said articulated arm (5). Preferably the actuator (19) comprises a hoist device with a belt, chord or chain engaging a number of pulleys.
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