Tensioning device of yarn twisting machine

The utility model relates to a tensioning device of a yarn twisting machine, which comprises a mounting frame, the mounting frame is connected with one end, far away from a hand wheel, of a rotating shaft, a sliding block is slidably mounted on the mounting frame, the sliding direction of the sliding block is parallel to the axis of the rotating shaft, a lead screw is rotatably mounted on a rack, and the axis of the lead screw is parallel to the sliding direction of the sliding block. The lead screw penetrates through the sliding block and is in threaded fit with the sliding block, the clamping block is placed on the top wall of the sliding block in an attached mode, and the sliding block is provided with a fixing piece connected with the clamping block. The yarn tensioning device has the advantages that after the two ends of the yarn are clamped between the clamping rod and the clamping block and between the sliding block and the clamping block respectively, the lead screw is rotated to drive the sliding blo