Grinding pad detection device

The utility model provides a grinding pad detection device which comprises a fixed guide rail which surrounds and is fixed on the side surface of a machine table; two ends of the moving rod move along the fixed guide rails; the signal transmitter is located at the first end of the moving rod and used for transmitting signals; the first signal receiver is positioned at the second end of the moving rod and is used for receiving the detection signal; and the second signal receiver is positioned at the first end of the moving rod and is used for receiving a reflected signal generated by reflecting the detection signal through a bulge on the grinding pad. The first signal receiver receives a detection signal, whether the polishing pad has a bump and the size of the bump can be judged, whether the slip sheet risk exists or not can be judged according to the size of the bump, the second signal receiver can receive and detect a signal reflected by the bump and determine the position of the bump, and therefore the bum