Logic control for fast-acting safety system
Woodworking machines with cutting tools and motors to drive the cutting tools are disclosed. The machines may be equipped with a detection system that detects a dangerous condition between the cutting tool and a person, and with a reaction system that performs a specified action upon detection of the dangerous condition. The machines also may be equipped with a control system that tests the operability of at least a portion of the detection system and/or the reaction system. The control system may disable the motor if the tested portion is inoperable.
1. A woodworking machine comprising:
a cutting tool for cutting workpieces;
at least one motor configured to drive the cutting tool;
a detection system configured to detect a dangerous condition associated with the cutting tool;
a brake mechanism having at least one replaceable single-use component, and controllable to stop the cutting tool if the dangerous condition is detected; and
a control system configured to detect whether the single-use component has been used, and to disable the at least one motor until the single-use component has been replaced.
2. The machine of claim 1 , where the at least one replaceable single-use component includes a fusible member.
3. The machine of claim 2 , where the control system is configured to detect whether the fusible member has been melted.
4. The machine of claim 2 , where the control system is configured to test the electrical continuity of the fusible member.
5. The machine of claim 2 , where the brake mechanism includes a capacitor adapted to store electrical charge, and where the control system is configured to determine the capacitance of the capacitor.
6. The machine of claim 2 , where the brake mechanism includes a capacitor adapted to store electrical charge, and where the control system is configured to determine the electrical charge stored on the capacitor.
7. A woodworking machine comprising:
a cutting tool for cutting workpieces;
at least one motor configured to drive the cutting tool;
a detection system configured to detect a dangerous condition associated with the cutting tool;
a reaction mechanism having a replaceable single-use component, and controllable to disable the cutting tool if the dangerous condition is detected; and
a control system configured to detect whether the single-use component has been used, and if so, to disable the at least one motor until the single-use component has been replaced.
8. The machine of claim 7 , where the replaceable single-use component includes a fusible member.
9. The machine of claim 8 , where the control system is configured to detect whether the fusible member has been melted.
10. The machine of claim 8 , where the control system is configured to test the electrical continuity of the fusible member.
11. The machine of claim 8 , where the reaction mechanism includes a capacitor adapted to store electrical charge, and where the control system is configured to determine the capacitance of the capacitor.
12. The machine of claim 8 , where the reaction mechanism includes a capacitor adapted to store electrical charge, and where the control system is configured to determine the electrical charge stored on the capacitor.