Makita Corporation

Katsuhito Fujinami

Tomoyuki Kondo

Yonosuke Aoki

Akira Naito

Akira Mizutani

Takahiro Kawakami

Hidekazu Suda

Junya Ishikawa

Akira Tomonaga

Hideharu Muto

Ken Yamauchi

Masatoshi Nakahama

Yasuyuki Fujimoto

Akira Ito

Ryo Imuta

Ken Goto

Yuta Izutsu

Kazuki Iyota

Jie Chen

Ya Wang

Fuchao Luan

Hong Jun Pang

An electric work machine in one aspect of the present disclosure includes an electric power input terminal, a motor, a circuit board, a first heat dissipation plate, and a second heat dissipation plate. The circuit board includes a first surface and an electronic circuit on the first surface. The electronic circuit controls supply of AC power to the motor. The electronic circuit includes an electronic component that generates Joule heat. The first heat dissipation plate is spaced from the first surface by a first distance in parallel to the first surface. The second heat dissipation plate is spaced from the first surface by a second distance in parallel to the first surface. The second heat dissipation plate is thermally coupled with the first heat dissipation plate. The second distance is smaller than the first distance.

Technique for dissipating heat in electric work machine

A voltage control device in one aspect of the present disclosure includes an appliance connector, a voltage output circuit, a manual switch, and a controller. The voltage output circuit outputs an operating voltage based on a direct voltage received from a direct-current power source. In response to a first electric appliance being connected to the appliance connector, the controller controls the voltage output circuit so as to fix the operating voltage. In response to a second electric appliance being connected to the appliance connector, the controller controls the voltage output circuit so as to vary the operating voltage in accordance with a manual operation applied to the manual switch.

Technique for controlling voltage to be supplied to electric appliance

An electrical device includes a battery-mount part () configured such that a battery used as a power supply of a power tool is mountable thereon, and a heat-generating element () for boiling water using electric power from the battery (B, B) mounted on the battery-mount part. The electrical device further includes a drip case () for holding a pod, in which a predetermined amount of tea leaves or coffee grounds is encased in a permeable bag-shaped element. A hot water supply () supplies the water boiled by the heat-generating element () automatically to the drip case (). An extraction part () in the drip case () allows a beverage produced by the hot water that has been poured onto (injected into) the pod to downwardly flow.

Electrical device for making beverages using power tool battery

An electric working machine in one aspect of the present disclosure includes a main current-path, a driving unit including a motor and at least one first semiconductor-switching-element, a controller, a bypass current-path, a second semiconductor-switching-element, and a switch driver. The main current-path is arranged between a positive electrode and a negative electrode of a battery. The driving unit is situated in the main current path. The bypass current-path is arranged in parallel with the driving unit. The second semiconductor-switching-element is situated in the bypass current-path. The switch driver causes the second semiconductor-switching-element to interrupt the bypass current-path in an event that a voltage value of a drive voltage applied to the driving unit is less than a threshold value, and causes the second semiconductor-switching-element to complete the bypass current-path in an event that the voltage value is equal to or greater than the threshold value.

Electric working machine and voltage suppressor circuit for electric working machine

A grinder according to one aspect of the present disclosure includes a motor, a housing for housing the motor, a spindle protruding from the housing and configured to be driven to be rotated by the motor, a wheel cover configured to cover a part of a tip end tool attached to the spindle, a detector configured to detect the wheel cover, and a controller configured to stop or restrict the spindle being driven by the motor in response to non-detection of the wheel cover by the detector.

Grinder

An electric working machine according to one aspect of the present disclosure includes a motor, a current detector, a voltage detector, and a load state determination unit. The current detector is configured to detect a current flowing through the motor during drive of the motor. The voltage detector is configured to detect an input voltage supplied to the motor during drive of the motor. The load state determination unit is configured to determine whether the motor is in a no-load operation state based on the detected current, the detected input voltage and an output voltage from an electric power source.

Electric working machine

A power tool enabled to detect an inadvertent rotation at higher accuracy includes a first sensor that detects a first driving information corresponding to a kinetic movement state of the tool body when the tool body is rotated around a longitudinal axis of the tool bit in the event of a working operation of the power tool, a second sensor that detects a second driving information corresponding to an output torque of the tool bit driven by the motor, and a controller connected to the first sensor and the second sensor for controlling the power tool. The controller is configured to calculate holding information corresponding to a holding force of a user to hold the tool body based on the first driving information and the second driving information and control the driving of the power tool based on the holding information.

Power tool

A drive device of the present invention includes a pair of drive switches, a first diode, a switching element, a current detection unit, a capacitor, a second diode, and a current control unit. The first diode, the switching element, and the current detection unit are arranged, in this order from one end of an armature in a motor, on a braking current path that is formed of the armature and a field winding in the motor when the pair of drive switches is in a brake position. The second diode is adapted to keep allowing a braking current to flow through the field winding when the switching element is in an off-state by directly connecting a partial path between the switching element and the current detection unit on the braking current path and the other end of the armature.

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Anjo, Japan

Katsuhito Fujinami