Panasonic Intellectual Property Management Co., Ltd.

Masayuki Nakahara

Takashi Kusagawa

Kenji Hanamura

Fumiiki Yoneda

Yoshikatsu Ito

Takahiro Kudoh

Tatsuto Kinjo

Masahiro Kinomura

An impact tool includes a motor, a control unit, an output shaft, a transmission mechanism, and an impact detection unit. The transmission mechanism includes an impact mechanism. The impact mechanism performs an impact operation according to magnitude of torque applied to the output shaft. The impact detection unit determines, based on at least one of an excitation current (current measured value) to be supplied to the motor or a torque current (current measured value) to be supplied to the motor, whether or not the impact operation is being performed. The control unit fulfills an impact response function by performing restriction processing in response to detection of the impact operation by the impact detection unit as a trigger. The restriction processing includes at least one of lowering the number of revolutions of the motor or stopping rotating the motor.

Impact tool, method for controlling the impact tool, and program

An electric power tool includes an electric motor (AC motor), an impact mechanism, an impact detecting unit, and a measuring unit. The impact mechanism performs an impact operation that generates impacting force by receiving motive power from the electric motor. The impact detecting unit determines whether or not the impact operation is being performed. The measuring unit measures at least one of a d-axis current or a q-axis current, each of which is supplied to the electric motor. The impact detecting unit determines, based on at least one of a measured value (current measured value) of the d-axis current or a measured value (current measured value) of the q-axis current, whether or not the impact operation is being performed. The measured values (current measured values) of the d-axis current and the q-axis current have been obtained by the measuring unit.

Electric power tool

An impact tool includes an electric motor, an impact mechanism, an acquisition unit, and a behavior decision unit (retreat detection unit). The electric motor includes a permanent magnet and a coil. The impact mechanism performs an impact operation that generates impacting force by receiving motive power from the electric motor. The behavior decision unit makes, based on at least one of a torque current acquisition value (current measured value) which is a value of a torque current acquired by the acquisition unit or an excitation current acquisition value (current measured value) which is a value of an excitation current acquired by the acquisition unit, a decision about behavior of the impact mechanism.

Impact tool

An impact tool includes a motor, a control unit, an output shaft, a transmission mechanism, and an impact detection unit. The transmission mechanism includes an impact mechanism. The impact mechanism applies impacting force to the output shaft while performing an impact operation. The impact detection unit determines, based on at least one of an excitation current (current measured value) to be supplied to the motor or a torque current (current measured value) to be supplied to the motor, whether or not the impact operation is being performed. The control unit places a limit on an increase in the number of revolutions of the motor before the impact detection unit detects the impact operation and removes the limit on the increase in the number of revolutions of the motor when the impact detection unit detects the impact operation.

An electric tool includes an AC motor (an electric motor) and a control unit. The AC motor includes a permanent magnet and a coil. The control unit is configured to perform control on operation of the AC motor. The control performed by the control unit includes field weakening control. In the field weakening control, the control unit causes a flux-weakening current to flow through the coil. The flux-weakening current is a current that generates, in the coil, a magnetic flux that weakens a magnetic flux of the permanent magnet.

Electric tool

A power control apparatus includes: a control unit that controls discharged power of a first battery and discharged power of a second battery; and a power acquisition unit that acquires a total power to be supplied from the first and second batteries to a load device connected to the first and second batteries. The control unit: in a first period, changes the discharged power of the first battery according to a change in the acquired total power, and changes the discharged power of the second battery toward a first direction in which the discharged power of the second battery approximates the discharged power of the first battery; and, in a second period after the first period, changes the discharged power of the second battery according to the change in the acquired total power, and changes the discharged power of the first battery toward a second direction opposite the first direction.

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Osaka, Japan

Masayuki Nakahara