Mechanical arm collision protecting device

The invention relates to a mechanical arm used for carrying wafers in the manufacturing process of semiconductors, in particular to a mechanical arm collision protecting device. The mechanical arm collision protecting device comprises a finger part, detection devices and an arm connecting plate which is mounted on a mechanical arm. The finger part is connected with the arm connecting plate through spring clips in a clamping mode, and the finger part which is impacted by external force can move relative to the arm connecting plate. The detection devices used for detecting the relative movement of the finger part and the arm connecting plate are mounted on the finger part and the arm connecting plate. According to the mechanical arm collision protecting device, when the mechanical arm collides with other objects, a sensor is used for detecting the relative movement of a finger connecting plate and the arm connecting plate, the mechanical arm is controlled to stop moving in emergency, the mechanical arm and the objects which collide with machines can be protected, and thus the loss caused by collision is reduced; after collision happens to mechanical arm fingers, parts do not need to be replaced, the spring clips are removed, and after the positions of positioning pieces and the positions of positioning holes are adjusted, the mechanical arm can recover to be in a normal using state.