A power tool comprising a power tool housing and a motor within the power tool housing. The motor including a rotor and a stator, the rotor coupled to a motor shaft to produce a rotational output. The power tool further includes a sensor within the power tool housing, the sensor configured to sense a free fall of the power tool, generate an output signal related to the sensed free fall. The power tool further includes a controller including a processor and a memory, the controller configured to receive the output signal from the sensor, detect the free fall of the power tool based on the output signal from the sensor, and brake the motor when the free fall of the power tool is detected.

In an electric machine tool having an electronics unit for implementing a starting lockout, the electric machine tool being connectable to an associated power source in an electrically conductive manner, the electronics unit is configured to receive power from the power source only for a limited, predefined period of time after an electrically conductive connection between the electric machine tool and the power source has been established.

A power tool includes a control for the motor of the power tool that senses an operating characteristic of the motor and controls the operation of the power tool based on the sensed characteristic. The sensed characteristic includes variations in reluctance of the motor. A controller may sense changes on load on the motor as a result of interaction between a working element such as a saw blade or drill bit and the work piece. The controlled operation may include variation in speed or torque or both, or may include stopping the motor. Emergency conditions may be sensed by changes in reluctance.

A power tool and methods are provided for detecting objects (e.g., flesh or other materials) in the operating path of a power tool's output component (e.g., saw blade or drill bit). An object detection sensor in the power tool generates an output signal indicative of a type of material detected in the operating path of the power tool. A power tool controller receives the object detection sensor output and determines when a material in the operating path of the power tool changes. The controller changes operation of a motor of the power tool (e.g., increasing or decreasing speed or stopping the motor) in response to the detected material change. The object detection sensor may include, for example, an RF sensor, a capacitive sensor, a camera, a conductivity probe, or an ultrasound probe.

The disclosure includes a protective device for a machine, a method of operating a protective device, and a protective system including the protective device and the machine. The protective device may include a sensor array disposed on the machine. The sensor array may have a plurality of time-of-flight (TOF) sensors arranged to form a sensible field for TOF measurements, and a controller configured to define a safety area within the sensible field, detect an object within the sensible field, and generate a safety output that controls an operation of the machine in response to the object being detected within the safety area. The machine may include woodworking machines or other machines having debris or particles in the surrounding environment during operation.

A power tool includes a housing, a handle coupled to the housing and configured to be grasped by a user during operation, a motor supported by the housing, a table, a mounting arm, and a controller. The table includes a sensing portion. The sensing portion includes a sensor. The sensing portion is configured to detect a body part of the user touching the table. The mounting arm supports the housing. The mounting arm is pivotably connected to the table and the housing. The controller is connected to the motor and the sensor. The controller is configured to receive a signal from the sensor related to whether the body part of the user is touching the table, and control operation of the motor in response to the sensing portion detecting that the body part of the user is touching the table.

A power tool including a motor configured to produce an output, and a sensor configured to measure an acceleration of the power tool along at least one of three spatial axes and generate an output signal related to the acceleration. The power tool further including a controller configured to receive the output signal related to the acceleration of the power tool from the sensor, compare the acceleration of the power tool to a free-fall acceleration threshold, initiate a timer when the acceleration of the power tool corresponds to the free-fall acceleration threshold, compare the timer to a free-fall timer threshold, and stop the motor from producing the output when the timer is greater than or equal to the free-fall timer threshold.

A machine tool includes a clamping mechanism for clamping/unclamping rotation of a rotary table. A load is measured when an unclamping command is output and then the rotary table is rotated after a set time set in the timer passes, and the set time of the timer is changed in response to a magnitude of the measured load. In this way, it is possible to prevent the clamping mechanism from being damaged due to a subsequent command given before unclamping ends, and extend a life span of a component.

A powered fastener driver includes a housing, a cylinder within the housing, the cylinder containing a pressurized gas, a piston within the cylinder and movable from a top-dead-center position to a bottom-dead-center position, a driver blade movably coupled to the piston, a lifter, a drive unit configured to provide torque to the lifter, and a sensor. The driver blade has a plurality of teeth defining a predetermined number of edges. The sensor is configured to detect an edge of one or more of the plurality of teeth and a controller in communication with the drive unit and the sensor. The controller is configured to count a number of edges detected by the sensor, compare the number of detected edges to the predetermined number of edges, and stop the drive unit when the number of detected edges is less than the predetermined number of edges.

A safety brake device for braking a machining tool includes at least one brake device configured as an at least two-part claw clutch. The claw clutch includes a first claw-clutch part, and a second claw-clutch part. The first claw-clutch part is arranged on the output shaft so as to allow no relative rotation, the second claw-clutch part is configured to allow no relative rotation with respect to the power tool, each claw-clutch part has a respective plurality of toothing elements, the respective plurality of toothing elements are configured to engage with one another during a braking operation to stop rotation of the output shaft, and a maximum angular spacing max of mutually adjacent toothing elements of at least one of the first plurality of toothing elements an the second plurality of toothing elements is determined depending on a maximum rotational speed of the output shaft.