Motion detecting system for use in a safety system for power equipment

A woodworking machine comprising:

• a working portion adapted to work when moving;
• a detection system adapted to detect a dangerous condition between a person and the working portion by imparting an electric signal to the working portion and monitoring the electric signal for at least one change indicative of the dangerous condition;
• a reaction system associated with the detection system to cause a predetermined action to take place relative to the working portion upon detection of the dangerous condition;
• and
• a motion detection system adapted to detect motion of the working portion and to disable the reaction system when the working portion is not moving.

A woodworking machine comprising:

• a working portion adapted to work when moving;
• a motor to move the working portion;
• a detection system adapted to detect a dangerous condition between a person and the working portion by imparting an electric signal to the working portion and monitoring the electric signal for at least one change indicative of the dangerous condition;
• and
• a reaction system associated with the detection system to cause a predetermined action to take place relative to the working portion upon detection of the dangerous condition;
• where the detection system and reaction system are configured to function when the motor is moving the working portion and for a defined period of time after the motor has been turned off, and where the reaction system is configured not to cause the predetermined action to take place after the defined period of time has past until the motor starts moving the working portion.

A woodworking machine comprising:

• a cutting tool;
• a motor to spin the cutting tool;
• a detection system adapted to detect a dangerous condition between a person and the cutting tool by imparting an electric signal to the cutting tool and monitoring the electric signal for at least one change indicative of the dangerous condition;
• a reaction system associated with the detection system to cause a predetermined action to take place relative to the working portion upon detection of the dangerous condition;
• and
• a control system adapted to monitor the detection system and control actuation of the reaction system, where the control system is adapted to trigger the reaction system if the dangerous condition is detected when the motor is spinning the cutting tool or during coast-down of the cutting tool after the motor is turned off and to deactivate the reaction system after coast-down.