Monitor for spindle of drilling machine - has piezoelectric sensor on shank of drill to measure radial and axial forces

摘要

The monitor for tool breakage, wear and control uses a sensor subjected to the cutting force. The sensor exploits the piezoelectric effect and is located on the shank of the drill at the place where it joins the machine's spindle. The sensor is normal to the axis of the drill. The sensor measures the radial force exerted on the drill or it may be located so as to measure both radial and axial forces. The electrical signal from the sensor is passed to evaluating circuitry that compares the sensor's signal with a stored set of references. The comparator's output is displayed or passed to the machine tool's control unit.