Patent ID: 7400106
Filing Date: 2008-07-15
Classification: B25B,B25F,H01H,H02P,Y10S

Abstract:
1. A powered tool for indicating to an operator that a torque limit has been reached comprising: a driver circuit for generating motor interface driving signals, a motor interface circuit coupled to a motor to selectively couple power to the motor in accordance with the interface driving signals, a torque limit signal generator for generating a torque limit signal, a motor torque signal generator for generating a torque signal corresponding to a torque generated by the motor, and a microcontroller for comparing the motor torque signal to the torque limit signal and for generating a torque limit indicating signal in response to the torque signal being equal to or greater than the torque limit signal so the driver circuit generates motor interface circuit control signals that cause the motor to vibrate so as to alert the operator that the torque limit has been reached.