Patent ID: 7644645
Filing Date: 2010-01-12
Classification: B23D,B23Q,B27B,F16P,Y10S,Y10T

Abstract:
1. A saw comprising: a circular cutting tool, where the cutting tool is adapted to spin; a rotatable arbor of conductive material configured to support the cutting tool; at least one bearing supporting the arbor; an insulating surface positioned and configured so that there is no electrically conductive path from the arbor to ground through the bearing; a motor configured to spin the arbor, where the motor includes an electrically grounded drive shaft; a gear train interconnecting the drive shaft and the arbor without a belt, where the gear train includes at least a first gear driven by the drive shaft, a second gear configured to drive the arbor, and a non-conductive contact surface positioned and configured so there is no electrically conductive path from the arbor to the drive shaft through the gear train; a detection system adapted to detect the occurrence of an unsafe condition between a person and the cutting tool, where the detection system is adapted to impart an electrical signal on the cutting tool; and a reaction system adapted to mitigate the unsafe condition upon the detection of the unsafe condition by the detection system.