Makita Corporation

Minebea Mitsumi Inc.

Takaharu Nakatsuka

Yuta Izutsu

Yoshihiro Ito

Kui Li

Kotaro Eguchi

A screwing machine includes a motor, an output shaft, a twist portion, a plate portion, a strain gauge, an amplification circuit. The output shaft is driven by the motor. To the output shaft, a bit is attachable. The twist portion is hollow. To the twist portion, torque applied to the output shaft is transmitted through a transmission element. The output shaft is configured to be indirectly twisted by the torque applied to the output shaft. The plate portion is integrally formed with the twist portion. The strain gauge is disposed on the twist portion. The amplification circuit is disposed on the plate portion. To the amplification circuit, a signal from the strain gauge is input.

Screwing machine and torque sensor

A torque sensor is less likely to lower detection accuracy. A screwing machine includes a motor including a stator and a rotor rotatable about a rotation axis, a gear case, a planetary gear, an internal gear connected to the planetary gear, a torque sensor including a front plate coupled to the internal gear, a rear plate supported by the gear case, a hollow portion located between the front plate and the rear plate, and a strain gauge fixed to the hollow portion, a bearing located between the stator and the rear plate and supporting at least a part of the rotor, and a bearing box surrounding the bearing and supporting the bearing.

Screwing machine and method for assembling screwing machine

A power tool includes a motor including a rotor and a stator disposed around the rotor; an output shaft to which a tip tool is attached and that is rotated by power generated by the motor; a torque sensor unit that is disposed between the stator and the output shaft in a front-rear direction parallel to a rotation axis of the motor and that is coupled to the output shaft; an amplifier circuit that amplifies a detection signal of the torque sensor unit; and a housing including a motor housing part for housing the motor and a grip part. The torque sensor unit is disposed forward of the stator. The grip part is disposed downward of the motor housing part. The amplifier circuit is disposed upward of the grip part. The amplifier circuit is disposed forward of a rear end part of the stator.

Growing community of inventors

Anjo, Japan

Takaharu Nakatsuka