Machines with safety systems are disclosed. The machine may take the form of woodworking machines including table saws, band saws, miter saws, hand-held circular saws, pneumatic chop saws, radial-arm saws, jointers, planars, routers and shapers. The machines may include an operative structure configured to perform a task, where the operative structure includes a cutting tool adapted to move in at least one motion, and a safety system adapted to detect the occurrence of an unsafe condition between a person and the cutting tool and for mitigating the unsafe condition. The safety system may include a detection subsystem and a reaction subsystem. The machine may also include a bypass or override mode where in an injury mitigation system is disabled for certain cuts.

Various safety systems for power tools, and in particular table saws include detection systems for detecting a dangerous condition relative to a blade of the power tool, reaction systems for taking mitigation action in response to detection of a dangerous condition. The safety system may detect, prevent, and/or mitigate a dangerous condition associated with the power tool.

Machines with safety systems are disclosed. The machine may take the form of woodworking machines including table saws, band saws, miter saws, hand-held circular saws, pneumatic chop saws, radial-arm saws, jointers, planars, routers and shapers. The machines may include an operative structure configured to perform a task, where the operative structure includes a cutting tool adapted to move in at least one motion, and a safety system adapted to detect the occurrence of an unsafe condition between a person and the cutting tool and for mitigating the unsafe condition. The safety system may include a detection subsystem and a reaction subsystem.

An engine-driven brush cutter (100) equipped with a safety device (42) that includes an acceleration sensor unit (24) attached to a drive unit (4) in an aslant orientation such that a detection axis (DA) of the sensor unit (24) inclines by an angle (θ1) relative to the up-and-down direction (V) of the brush cutter (100). This inclined orientation of the detection axis (DA) contributes to lowering the sensitivity of the sensor unit (24) to engine vibration to which the safety device should not be sensitive so much.

An engine-driven brush cutter (100) equipped with a safety device (42) that includes an acceleration sensor unit (24) attached to a drive unit (4) in an aslant orientation such that a detection axis (DA) of the sensor unit (24) inclines by an angle (θ1) relative to the right-and-left direction (R-L) of the brush cutter (100). This inclined orientation of the detection axis (DA) contributes to lowering the sensitivity of the sensor unit (24) to impulses in the direction parallel to a moving direction of a cutting blade (40) operated by an operator at work.

Various safety systems for power tools, and in particular table saws include detection systems for detecting a dangerous condition relative to a blade of the power tool, reaction systems for taking mitigation action in response to detection of a dangerous condition. The safety system may detect, prevent, and/or mitigate a dangerous condition associated with the power tool.

A safety system prevents cutting machine operators from being accidentally carried through the infeed chute into the machine's cutting mechanism. An operator wears a safety device on his wrist and/or ankle and a sensor array mounts on opposing sides of the cutting machine's infeed chute. The sensor array elements are wound in opposite directions and connect in series opposing. The magnetic field of the safety device induces a current in the sensor array as it moves in the proximity of the sensor array. The safety system generates a signal which is proportional to the sum of the induced currents. When the signal exceeds a threshold, the safety system shuts off power to the feed mechanism and/or the cutting blades of the cutting machine, preventing injury to the operator.

Table saws are disclosed. The table saws can include a blade, an arbor, an arbor block, an elevation carriage, and a latch that connects the arbor block and the elevation carriage. The arbor block can have a first position in which the latch connects the arbor block and the elevation carriage, and a second position in which the latch does not connect the arbor block and the elevation carriage. The arbor block can pivot from the first position to the second position upon the occurrence of a retraction force. The table saw can include an actuator to cause the occurrence of the retraction force, and detection electronics to detect contact between the blade and a person. Woodworking machines with detection and reaction systems are also disclosed. A reaction system can include an explosive that causes retraction of a cutting tool.

A safety system prevents cutting machine operators from being accidentally carried through the infeed chute into the machine's cutting mechanism. An operator wears a safety device on his wrist and/or ankle and a sensor array mounts on opposing sides of the cutting machine's infeed chute. The sensor array elements are wound in opposite directions and connect in series opposing. The magnetic field of the safety device induces a current in the sensor array as it moves in the proximity of the sensor array. The safety system generates a signal which is proportional to the sum of the induced currents. When the signal exceeds a threshold, the safety system shuts off power to the feed mechanism and/or the cutting blades of the cutting machine, preventing injury to the operator.

Table saws with safety systems are disclosed. The safety systems detect and react to dangerous conditions, such as contact between the blade and a person. The table saws may include a switch, a first light that illuminates to indicate the safety system is operable, and a second light that illuminates to indicate that the safety system is inoperable. The switch may not power the saw when switched on if the second light is illuminated.