| 摘要 |
The purpose of the present invention is to provide a hoist drive mechanism whereby the maximum thrust required of a direct acting type actuator can be kept to a relatively low level. In this hoist drive mechanism (2), thrust produced during extension of a direct acting stem (B) of a direct acting type actuator (A) is converted to torque that swings a swing shaft (C), this torque being used to elevate a hoist (1B) with respect to a base (1A) of a hoisting apparatus (1). One end (3A) of a tension-reliant elongated power transmission (3) having flexibility is linked to the distal end of the direct acting stem (B), and the other end (3B) of the tension-reliant power transmission (3) is affixed to the swing shaft (C), and attached to a power transmission swing body (4) having formed thereon an arcuate surface to which the tension-reliant power transmission (3) conforms. When the direct acting stem (B) is in a retracted state, the tension-reliant power transmission (3) flexes and conforms to the arcuate surface, and when the direct acting type actuator is driven, extending the direct acting stem (B), the tension-reliant power transmission (3) is withdrawn from the power transmission swing body (4) in such a way as to separate from the arcuate surface in small increments. |
