Tensioning device for elevator

The utility model relates to the technical field of elevator operation, in particular to a tensioning device for an elevator, which comprises a positioning shaft, a tensioning device and a tensioning device, the swing arm is rotatably matched with the positioning shaft, one end of the swing arm extends in the direction of the speed limiter rope wheel, and the other end of the swing arm extends in the direction of the detection switch; the reset spring is arranged between the positioning shaft and the swing arm and used for keeping the other end of the swing arm away from the detection switch; wherein the speed limiter rope wheel descends to be matched with one end of the swing arm so as to achieve rotation of the swing arm, and the other end of the swing arm is used for triggering the detection switch so as to achieve power failure of the elevator; under the blocking of one end of the swing arm, the movement of the speed limiter rope wheel deviates or shakes, so that the speed limiter rope wheel crosses one e