Band saws with high-speed safety systems are disclosed. The band saws include a detection system adapted to detect a dangerous condition between a blade and a person. A reaction system performs a specified action such as stopping the blade upon detection of the dangerous condition.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of and priority from the following U.S. Provisional Patent Application, the disclosure of which is herein incorporated by reference: Ser. No. 60/308,492, filed Jul. 27, 2001.
A sensing mechanism (12) for detecting user contact with an active portion (26) of the power tool (10) is provided. In addition, a safety mechanism (14) for preventing prolonged user contact with the active portion (26) of a power tool (10) is provided. The safety mechanism (14) is configured to actuate upon receipt of a signal from the sensing mechanism (12). According to a first aspect, the safety mechanism (14) is arranged to rapidly displace the active portion (26) away from a user extremity. Alternatively, according to a second aspect, the safety mechanism (14) is arranged to rapidly urge an extremity of the user away from the active portion (26) of the power tool (10).
Woodworking machines are disclosed having movable cutting tools for cutting workpieces in a cutting region. The machines include a detection system adapted to detect one or more dangerous conditions between a person and the cutting tools, and a reaction system associated with the detection system. The reaction system is configured to retract the cutting tool at least partially away from the cutting region upon detection of a dangerous condition by the detection system.
Cutting machines with high-speed safety systems, and firing subsystems used in high-speed safety systems, are disclosed. The cutting machines may include a detection system adapted to detect a dangerous condition between a cutting tool and a person. A reaction system performs a specified action, such as stopping the cutting tool, upon detection of the dangerous condition. A fusible member or explosive may be used to trigger the reaction system to perform the specified action. A firing subsystem may be used to fuse the fusible member or fire the explosive upon detection of the dangerous condition.
A machine such as a saw, jointer, planer, etc. is disclosed. The machine has cutting tool, a direct drive mechanism configured to move the cutting tool, a detection system adapted to detect the occurrence of an unsafe condition between a person and the cutting tool, and a reaction system adapted to mitigate the unsafe condition upon the detection of the unsafe condition by the detection system. An electrical signal is imparted on the cutting tool, and the signal is used to determine the occurrence of the unsafe condition. The direct drive mechanism is electrically isolated so that the electric signal may be imparted on the cutting tool. The electric isolation may be achieved through configurations such as insulated bearings, a substantially non-conductive housing, and a substantially non-conductive coupling joining two shaft portions.
Woodworking machines including cutting tools and motors adapted to drive the cutting tools are disclosed. The machines also include a detection system adapted to detect a dangerous condition between the cutting tool and a person, and a reaction system adapted to perform a specified action upon detection of the dangerous condition. The machines further include a control system adapted to test the operability of at least a portion of the detection system and/or the reaction system. The control system is adapted to disable the motor if the tested portion is inoperable. The control system also includes a test mode to test whether the detection system is working, to test whether various materials would be detected by the detection system, and/or to test whether various materials would trigger the reaction system.
