| 摘要 |
The trolley is used in a fall arrest system and comprises a frame, a channel formed within the frame for engagement therein of a lifeline, and a self-blocking mechanism carried by the frame. The self-blocking mechanism comprises a brake movable between a braking position wherein the brake extends within the channel for frictionally engaging the lifeline; and an enabling position wherein the brake clears the channel for clearing the lifeline. The self-blocking mechanism also comprises a manually operable enabling actuator connected to the brake and capable of forcing the brake towards the enabling position. The self-blocking actuator further comprises a fall arrest actuator distinct from the brake and from the enabling actuator, and connected to the brake, the fall arrest actuator being movable with respect to the frame in a direction transversal to the channel between a fall position wherein the fall arrest actuator forces the brake towards the braking position and an idle position wherein the fall arrest actuator does not force the brake towards the braking position, with the fall arrest actuator capable of overriding the enabling actuator to force the brake towards the braking position. |
