The present disclosure relates to an electric tool and a power supply method for an electric tool. The electric tool includes: a housing; a motor, accommodated in the housing; battery pack mounting portions, at least two battery packs being detachably mounted in the battery pack mounting portions,; a main switch, being in an open state or a closed state according to an operation of a user, when the main switch is in a closed state, the battery packs are capable of supplying power to the motor, and when the main switch is in an open state, the battery packs stop supplying power to the motor; and a control assembly, detecting a state of the main switch, when the main switch is in an open state, the control assembly controls transfer of electric energy of a battery pack with a high voltage to a battery pack with a low voltage of the at least two battery packs.

The present disclosure relates to an electric tool and a power supply method for an electric tool. The electric tool includes: a housing; a motor, accommodated in the housing; battery pack mounting portions, at least two battery packs being detachably mounted in the battery pack mounting portions,; a main switch, being in an open state or a closed state according to an operation of a user, when the main switch is in a closed state, the battery packs are capable of supplying power to the motor, and when the main switch is in an open state, the battery packs stop supplying power to the motor; and a control assembly, detecting a state of the main switch, when the main switch is in an open state, the control assembly controls transfer of electric energy of a battery pack with a high voltage to a battery pack with a low voltage of the at least two battery packs.

A concrete vibrator motor includes a motor assembly that provides actuation and a cage assembly that surrounds the motor assembly to shield it and provide one or more operator handles. The motor assembly includes a motor housing, a motor pod, and a plurality of brushes that are used to secure the motor pod within the motor housing. The cage assembly includes a pair of endcaps and handles arranged beneath the endcaps. The endcaps are configured to inhibit fluid ingression into the motor housing while permitting air circulation between the ambient environment outside of the motor housing and within the motor housing. Thus, the motor assembly may intake air into the motor housing and exhaust air therefrom without contamination from the ambient environment.

A method and device for providing a resistance force to a user is disclosed. To provide a resistance force, the method includes measuring an angle of a joint of a user using a sensor of a wearable device, determining a resistance level for the joint based on the measured angle, determining a connection ratio of a motor driver circuit of the wearable device that corresponds to the resistance level, and controlling a motor based on the determined connection ratio of the motor driver circuit.

A continuously rotating electric motor includes a rotor provided with permanent magnets and a stator formed by two coils in which, when the rotor is rotating, two induced voltage signals (U.sub.B1 and U.sub.B2) are respectively generated, which signals have an electric phase shift φ where 5°≤φ≤90°, preferably 30°<φ<65°. The control device includes a circuit for detecting intersection times (T.sub.C) at which values of the two induced voltage signals are substantially equal. The control device is arranged to generate electric driving pulses to rotate the rotor, which are respectively initiated at initiation times determined by respective intersection times, and such that the electric driving pulses can be applied to the two coils arranged in series. Preferably, the control device is arranged such that the initiation times of the electric driving pulses occur directly after detections of corresponding intersection times.

The motor control apparatus includes: a setting unit configured to set a limit value of coil current flowing through a coil of a motor; a current supply unit configured to supply the motor with the coil current in a range not exceeding the limit value set by the setting unit; a detection unit configured to detect a current value of the coil current; and a comparison unit configured to compare an average value of the current value detected by the detection unit over a predetermined time period with a first threshold value. When the average value has exceeded the first threshold value, the setting unit updates the limit value in a decreasing manner.

A motor driving circuit includes a stepping motor driving circuit that controls driving of a stepping motor, a DC motor driving circuit that controls driving of a DC motor, and a control circuit that controls the stepping motor driving circuit and the DC motor driving circuit. The control circuit, upon accepting a driving instruction for driving the stepping motor in the middle of the DC motor driving circuit performing driving of the DC motor, stops driving of the DC motor by the DC motor driving circuit, and starts driving of the stepping motor by the stepping motor driving circuit.

A control unit is presented for controlling a driving unit arranged for adjustment of one or more first air guiding flaps of a motorised vehicle between a first outer position and a second outer position. The control unit comprises a communication module for communicating with a vehicle control network for receiving first adjustment instructions for adjusting the first flap, a power supply module comprising an input power terminal for receiving power from a vehicle power network and a first output power terminal for supplying a first current to the driving unit. The control unit further comprises a current sensor module for sensing variations in the first supply current and a control module arranged to control the first supply current in accordance with the adjustment instructions and the sensed variations. By separating the control module from the driving unit, functionality of the control module may be shared over multiple driving units.

A concrete vibrator system includes a concrete vibrator having a motor, a vibratory head that is actuated by the motor, and a controller that controls the motor. The concrete vibrator system may also include one or more remote devices or servers that wirelessly communicate with the controller of the concrete vibrator. The remote device may monitor the speed output by the motor and the voltage supplied to the motor to achieve a set speed via the controller, and display information representative of the motor speed and motor voltage to the user. Moreover, the speed output by the motor may be controlled using voltage supplied to the motor.

An electric apparatus for controlling movement of a target object by performing first and second feedback controls, based on a detection signal obtained from detecting the movement of the target object, generates an operation quantity on the target object based on first and second operation quantities for the second feedback control if one of a predetermined target value and an estimated first state quantity of the target object is higher than a first threshold value, and generates the operation quantity on the target object using only the first operation quantity from among the first and the second operation quantities if one of the target value and the first state quantity of the target object is lower than the first threshold value.