Makita Corporation

Junya Inuzuka

Tatsuya Nagahama

Takashi Momose

Yusuke Ichioka

An electric work machine includes coils formed reliably. The machine includes a stator, a rotor rotatable about a rotation axis, and an output unit drivable by the rotor. The stator includes a stator core including a cylindrical yoke and teeth protruding radially outward from the yoke, an insulator fixed to the stator core, and coils each wound around a corresponding one of the teeth with the insulator in between. The insulator includes a first cover covering a first end face of the yoke in a first axial direction and a rib on the first cover and supporting a wire connecting the coils. The rotor includes a rotor core outside a periphery of the stator and a magnet fixed to the rotor core.

Electric work machine with stator having insulator with first cover and ribs supporting wire

A power tool () includes a motor () having a stator () and a rotor (). The stator () includes front and rear insulators () respectively disposed forward and rearward of a stator core () in an axial direction thereof. At least six coils () are respectively wound on the stator () such that the coils () are wound through the front and rear insulators (). Winding wires () respectively electrically connect circumferentially-adjacent pairs of the coils (). A short circuiting device () short circuits respective pairs of windings () that are located diagonally or diametrically across from one another.

Power tool

An electric work machine can appropriately detect rotation of a rotor. The electric work machine includes a stator including a stator core, an insulator fixed to the stator core, and a coil attached to the insulator, a rotor rotatable about a rotation axis and including a rotor core and a magnet fixed to the rotor core, a stator base supporting the stator, a sensor board supported by the stator base and including a magnetic sensor that detects the magnet, and an output unit drivable by the rotor.

Electric work machine

A sensor board is downsized. An electric work machine includes a stator, a rotor rotatable about a rotation axis, magnetic sensors, a sensor board supporting the magnetic sensors, and an output unit drivable by the rotor. The stator includes a stator core, an insulator, and coils including first-, second-, and third-phase coils. The rotor includes a rotor core and magnets fixed to the rotor core. The magnetic sensors detect the magnets and include, in a circumferential direction, a first magnetic sensor aligned with at least a portion of a first coil pair, a second magnetic sensor aligned with at least a portion of a second coil pair, and a third magnetic sensor aligned with at least a portion of a third coil pair.

In the brushless motor disposed in a hammer drill, while a stator core of a stator is formed by joining a plurality of divided cores divided in a circumferential direction, varnishes are applied over a coil and joining portions between the divided cores.

Electric tool

A rotor has reduced weight. A hammer drill includes a motor including a stator and a rotor rotatable relative to the stator. The rotor includes a rotor core having a first space, and a permanent magnet fixed on the rotor core.

A power tool includes a housing and a brushless motor, the brushless motor having a stator and a rotor inside the housing, the rotor including a rotor core having a plurality of axially extending through holes and a permanent magnet in each of the plurality of through holes. The rotor is provided with at least one positioning structure by which the rotor core can be held in a desired circumferential orientation while the permanent magnets are inserted into the through holes.

Growing community of inventors

Anjo, Japan

Junya Inuzuka