Power cable pay-off pulley mechanism for power construction

The invention discloses a power cable pay-off pulley mechanism for power construction. The pulley mechanism comprises two symmetrically arranged frames, wherein a roller is rotationally connected between the two frames, one end of the roller is fixedly connected with a connecting rod, and the connecting rod penetrates through the corresponding frame and is fixedly connected with a U-shaped rod. According to the pulley mechanism, through mutual cooperation of the roller, the U-shaped rod, a mounting block, an air pushing mechanism, an air guide pipe, movable blocks and an extrusion mechanism, the U-shaped rod is utilized to drive the air pushing mechanism to move, so that air flow in the air guide pipe is changed; when the U-shaped rod is at a low rotating speed, a corresponding first piston block does not move or slightly moves; and when the U-shaped rod is at a high rotating speed, the first piston block is large in moving amplitude, so that the movable blocks move downwards, at the moment, a rotating rod ma