Safety brakes for circular saw blades, circular saws that include the safety brakes, and methods of operating circular saws are disclosed herein. The safety brakes include a sensor assembly, a brake assembly, and an actuator assembly. The sensor assembly is configured to detect an actuation parameter and to generate a trigger signal responsive to detection of the actuation parameter. The brake assembly includes a brake cam and a brake pad. The brake cam is configured to selectively transition between a disengaged configuration and an engaged configuration and is configured to operatively engage a planar side surface of the circular saw blade. The brake pad includes a pad friction material and is positioned such that the pad friction material faces toward the brake cam. The actuator assembly is configured to selectively transition the brake cam from the disengaged configuration to the engaged configuration responsive to receipt of the trigger signal.

Safety brakes for circular saw blades, circular saws that include the safety brakes, and methods of operating circular saws are disclosed herein. The safety brakes include a sensor assembly, a brake assembly, and an actuator assembly. The sensor assembly is configured to detect an actuation parameter and to generate a trigger signal responsive to detection of the actuation parameter. The brake assembly includes a brake cam and a brake pad. The brake cam is configured to selectively transition between a disengaged configuration and an engaged configuration and is configured to operatively engage a planar side surface of the circular saw blade. The brake pad includes a pad friction material and is positioned such that the pad friction material faces toward the brake cam. The actuator assembly is configured to selectively transition the brake cam from the disengaged configuration to the engaged configuration responsive to receipt of the trigger signal.

A method is provided for detecting a substance, preferably human tissue, in the vicinity of a mobile tool, wherein the substance to be detected has different electrical characteristics from a material that can be processed by the mobile tool. In the method, a change is detected in a capacitance formed by the tool and a counter electrode that is electrically insulated from the tool. A periodic change in the capacitance is detected and the change is produced by the presence of the substance in a region in relation to the tool and by a periodic change in a geometrical characteristic of the tool in this region as the tool moves.

A method is provided for detecting a substance, preferably human tissue, in the vicinity of a mobile tool, wherein the substance to be detected has different electrical characteristics from a material that can be processed by the mobile tool. In the method, a change is detected in a capacitance formed by the tool and a counter electrode that is electrically insulated from the tool. A periodic change in the capacitance is detected and the change is produced by the presence of the substance in a region in relation to the tool and by a periodic change in a geometrical characteristic of the tool in this region as the tool moves.

A tool device, in particular a saw device, having a tool for processing a workpiece located in a working area. The tool device includes a tool braking device for braking a tool rotary movement of the tool, and a multi-joint arrangement by means of which the tool can be pivoted selectively in a feed direction into the working area or in a removal direction out of the working area. The multi-joint arrangement is designed to, while maintaining the pivotability of the tool, absorb and/or redirect forces occurring during braking of the tool rotary movement, so that the tool is not pivoted in the feed direction by the forces occurring during braking of the tool rotary movement or is pivoted in the removal direction by the forces occurring during braking of the tool rotary movement.

A tool device, in particular a saw device, having a tool for processing a workpiece located in a working area. The tool device includes a tool braking device for braking a tool rotary movement of the tool, and a multi-joint arrangement by means of which the tool can be pivoted selectively in a feed direction into the working area or in a removal direction out of the working area. The multi-joint arrangement is designed to, while maintaining the pivotability of the tool, absorb and/or redirect forces occurring during braking of the tool rotary movement, so that the tool is not pivoted in the feed direction by the forces occurring during braking of the tool rotary movement or is pivoted in the removal direction by the forces occurring during braking of the tool rotary movement.

The disclosure relates to a handheld work apparatus having a drive motor, wherein the drive motor drives at least one tool. The work apparatus includes a mechanical braking device for the tool, wherein the braking device can be adjusted between a braked position and a released position by the operator via an actuating lever. The work apparatus includes an electromagnet and an armature cooperating with the electromagnet. The electromagnet is configured to hold the braking device in its released position. The work apparatus has at least one control device. The at least one control device is configured to ascertain the position of the armature with respect to the electromagnet to determine the position of the braking device.

Power saws and features for power saws are disclosed. Various features are particularly relevant to jobsite or benchtop table saws, such as a trunnion formed from a shaped tube, an elevation carriage, and an arbor block retention mechanism. Other features are particularly relevant to table saws, hand-held circular saws, track saws, miter saws, and band saws with active injury mitigation technology, such as an electrically isolating gear and an overmolded arbor/gear element.

Fast-acting and low-inertia actuators useable in various applications where a high force must be applied very quickly are disclosed. Power tools with detection systems configured to detect a dangerous condition between a person and a cutting tool are disclosed. In power tools, for example in a woodworking machine, a fast-acting and low-inertial actuator as disclosed herein can be used to retract a blade upon detection of a dangerous condition by a detection system. The actuator includes a charge of pressurized fluid and one or more electromagnets to selectively retain or release the pressurized fluid.

Systems and methods for braking a power tool using a stamped brake resistor. The power tool includes a motor, a trigger configured to be actuated, and a brake switch coupled to the motor. A brake resistor assembly is selectively coupled to the motor via the brake switch and includes a stamped brake resistor. The stamped brake resistor includes a terminal portion and a resistive portion. The resistive portion includes a planar serpentine path. A controller including an electronic processor and a memory is coupled to the trigger, the motor, and the brake switch, and is configured to control power delivered to the motor based on a position of the trigger, determine to brake the motor during operation of the motor, and activate, in response to determining to brake the motor, the brake switch to connect the stamped brake resistor to the motor.