Makita Corporation

Kunihisa Shima

Hirokatsu Yamamoto

Ryo Umemoto

Yuki Kawai

Hitoshi Suzuki

Yoshitaka Ichikawa

Goshi Ishikawa

Takaaki Osada

An electric power tool in one aspect of the present disclosure includes a motor, an output shaft, a torque detector, a correction circuit, and an output circuit. The correction circuit corrects a drive command value based on load torque detected by the torque detector. The drive command value indicates a magnitude of electric power to be supplied to the motor. The output circuit outputs a drive signal indicating the drive command value. The drive circuit (i) receives the drive signal from the output circuit and (ii) supplies electric power in accordance with the drive signal to the motor to drive the motor.

Technique for controlling motor in electric power tool

A cart may include: a driving wheel; a motor configured to rotate the driving wheel; a motor drive circuit configured to drive the motor; a motor brake circuit configured to electrically brake the motor; a rotation speed sensor configured to detect a rotation speed of the motor; and a control device configured to control the motor via the motor drive circuit and the motor brake circuit based on a target rotation speed of the motor and the rotation speed detected by the rotation speed sensor. The motor brake circuit may include an electronically variable resistance element configured to operate in a linear mode and a switching mode in response to a control input signal. The motor brake circuit may be configured to operate the electronically variable resistance element in the linear mode when braking the motor.

Cart

An electric power tool disclosed herein may include an actuator; a control unit; and a main switch. When the main power is on, the control unit may be capable of executing at least one sequence operation in which the actuator is operated according to a predetermined sequence. When the operation to switch the main power from on to off is performed on the main switch during execution of the at least one sequence operation: the main power may be kept on and electric power supply to the actuator may be continued until the at least one sequence operation under execution is completed; and the electric power supply to the actuator may be cut off and the main power may be switched from on to off after the at least one sequence operation under execution has been completed.

Electric power tool

A rotary impact tool in one aspect of the present disclosure includes a motor, an impact mechanism, an impact detector, and a controller. The controller executes constant duty ratio control from when the motor is started until an impact is detected by the impact detector. The controller executes constant rotation speed control in response to detection of an impact by the impact detector.

Rotary impact tool

A tying machine may include a feeding mechanism configured to feed a tying string, a battery, and a voltage detection circuit configured to detect a voltage of the battery. The feeding mechanism may include a feeding motor to which power is supplied from the battery. The tying machine may be configured to set a duty ratio for driving the feeding motor when feeding the tying string, in accordance with the voltage of the battery detected by the voltage detection circuit.

Tying machine

A tying machine may include a twisting mechanism configured to twist a tying string. The twisting mechanism may include a twisting motor. The tying machine may be configured to obtain torque acting on the twisting motor as a twisting torque value, and stop the twisting motor when a predetermined tying completion condition is satisfied. The tying completion condition may include that an elapsed time since a rise in the twisting torque value was detected reaches a first predetermined time.

An electric power tool according to one aspect of the present disclosure includes a main body, a motor, a tool holder configured to hold a tool bit, a hammer, a motion converter, a rotation transmitter, a first load detector, a second load detector, and a motor controller. The first load detector detects, based on information indicating a drive state of the motor, a load imposed from a work piece to the tool bit. The second load detector detects, based on information indicating a behavior of the main body, a load imposed from the work piece to the tool bit. The motor controller sets an upper limit of rotational speed of the motor to a predetermined no-load rotational speed in response to no-load on the tool bit being detected by both the first load detector and the second load detector.

Electric power tool and method of controlling rotational speed of motor in electric power tool

A rebar tying device is configured to tie a plurality of rebars by a wire. The rebar tying device includes a feeder configured to feed the wire wound around a reel by a rotation of a feeding motor; a guide configured to guide the wire fed by the feeder to around the plurality of rebars; a cutter configured to cut the wire fed by the feeder at a predetermined position; a twister configured to twist the wire around the plurality of rebars; a battery configured to supply power to the feeding motor; and a control unit. The control unit configured to control a feeding length of the wire by controlling an energizing time of the feeding motor based on a predetermined feeding length of the wire.

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Anjo, Japan

Kunihisa Shima