A hand-held power tool includes a housing with a handle, a transmission, a drive motor, a tool receiver, and a first switch unit. The transmission and drive motor are arranged in the housing, the transmission being configured to transmit a torque generated by the drive motor to the tool receiver, which is configured to rotate about a rotation axis. The first switch unit is configured to control the drive motor, and has a first switching element and a second switching element that are configured to operate the first switch unit and that enable an operator to influence various control variables of the drive motor. The second switching element is further configured to control a direction of the rotation of the drive motor, and upon actuation, execute a linear movement that is substantially parallel to the rotation axis.

A hand-held power tool includes a housing with a handle, a transmission, a drive motor, a tool receiver, and a first switch unit. The transmission and drive motor are arranged in the housing, the transmission being configured to transmit a torque generated by the drive motor to the tool receiver, which is configured to rotate about a rotation axis. The first switch unit is configured to control the drive motor, and has a first switching element and a second switching element that are configured to operate the first switch unit and that enable an operator to influence various control variables of the drive motor. The second switching element is further configured to control a direction of the rotation of the drive motor, and upon actuation, execute a linear movement that is substantially parallel to the rotation axis.

A motor-driven integrated circuit comprises a plurality of position comparators, a timer and a central processing. Each of the plurality of position comparators receives a pole detection signal denoted a position of a rotor of a motor. The timer receives a timing interrupt signal output by the plurality of position comparators when a predetermined edge of the pole detection signal is generated and records a time of the predetermined edge. The central processing unit obtains a rotation speed of the motor according to a time difference between two predetermined edges.

A motor-driven integrated circuit comprises a plurality of position comparators, a timer and a central processing. Each of the plurality of position comparators receives a pole detection signal denoted a position of a rotor of a motor. The timer receives a timing interrupt signal output by the plurality of position comparators when a predetermined edge of the pole detection signal is generated and records a time of the predetermined edge. The central processing unit obtains a rotation speed of the motor according to a time difference between two predetermined edges.

An electric motor-driven parking brake of a motor vehicle can be released in an emergency by applying emergency current from a parallel emergency current source to the motors controlling the parking brake. The direction of the emergency current is selected to reverse the motors, i.e., release the parking brake.

The invention relates to a soft starter (10) for connecting at least one main circuit (12, 14, 16), each of which includes a bypass circuit (20) having a semiconductor switch (22). Said soft starter (10) comprises a control unit (40) for actuating the bypass circuit (20), and the control unit (40) is equipped with a control signal input (44). According to the invention, the control unit (40) has a separate safety signal input (42).

A smart power switch for a swimming pool vacuum having a battery powered motor for driving a propeller within a vacuum head to create thrust and suction; the power switch including a microprocessor combined with two integrated motor-driver integrated circuits for driving the motor at different speeds and for detecting and clearing motor jams. Red, green and blue LED indicators notify the user of the state of the motor and motor driver. The microprocessor detects spikes in motor current to determine a motor jam and operates the motor driver to control the motor, including stopping and reversing the motor, to clear an obstruction in the vacuum head.

A drive circuit for an electric motor having a wound stator and a permanent magnet rotor, includes a controllable bidirectional AC switch connected in series with a stator winding between two terminals for connecting to an AC power supply. First and second position sensors detect the position of magnetic poles of the rotor. A voltage regulating circuit is connected between the two terminals and the controllable bidirectional AC switch and configured to supply power to the first sensor during the positive cycle and to the second position sensor during the negative cycle of the AC power supply such that the controllable bidirectional AC switch is switched between a conductive state and a non-conductive state in a preset manner, thus enabling the stator to rotate the rotor in only one predetermined direction during start-up.

An electric tool includes: a motor configured to be driven by PWM controlling a semiconductor switching element; a trigger configured to adjust startup and rotation of the motor; a changeover switch configured to switch a rotation direction of the motor between a forward rotation and a reverse rotation; a power transmission mechanism configured to rotate a tip tool by the motor, and a controller configured to control rotation of the motor. When the reverse rotation is set by the changeover switch, the controller PWM controls the semiconductor switching element at a high duty ratio after the trigger is pulled to drive the motor, and thereafter drives the motor at a state where the high duty ratio is changed to a low duty ratio.

An electric tool includes: a motor configured to be driven by PWM controlling a semiconductor switching element; a trigger configured to adjust startup and rotation of the motor; a changeover switch configured to switch a rotation direction of the motor between a forward rotation and a reverse rotation; a power transmission mechanism configured to rotate a tip tool by the motor, and a controller configured to control rotation of the motor. When the reverse rotation is set by the changeover switch, the controller PWM controls the semiconductor switching element at a high duty ratio after the trigger is pulled to drive the motor, and thereafter drives the motor at a state where the high duty ratio is changed to a low duty ratio.