US 12,390,906 B2
Screw-tightening tool
Hiroki Ikuta, Anjo (JP); and Takumi Hayashi, Anjo (JP)
Assigned to MAKITA CORPORATION, Anjo (JP)
Filed by MAKITA CORPORATION, Anjo (JP)
Filed on Sep. 20, 2022, as Appl. No. 17/948,367.
Claims priority of application No. 2021-168596 (JP), filed on Oct. 14, 2021.
Prior Publication US 2023/0124236 A1, Apr. 20, 2023
Int. Cl. B25B 21/00 (2006.01); B25F 5/00 (2006.01)
CPC B25B 21/00 (2013.01) [B25F 5/001 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A screw-tightening tool comprising:
a housing;
a motor within the housing, the motor having an output shaft configured to be rotationally driven selectively in a first direction that corresponds to a direction for tightening a screw and in a second direction that corresponds to a direction for loosening the screw and that is opposite to the first direction;
a spindle that is supported by the housing to be movable along a driving axis and to be rotatable around the driving axis, the driving axis defining a front-rear direction of the screw-tightening tool, the spindle having a front end portion configured to removably receive a tool accessory;
a first clutch that is operably coupled to the output shaft and the spindle and configured to transmit power from the output shaft to the spindle only when the output shaft is rotationally driven in the first direction, and is configured to not transmit power from the output shaft to the spindle when the output shaft is rotationally driven in the second direction; and
a second clutch that is operably coupled to the output shaft and the spindle and configured to transmit power from the output shaft to the spindle only when the output shaft is rotationally driven in the second direction, and is configured to not transmit power from the output shaft to the spindle when the output shaft is rotationally driven in the first direction,
wherein:
an output rotation speed of the spindle when the power is transmitted via the first clutch is different from an output rotation speed of the spindle when the power is transmitted via the second clutch, in response to a same rotation speed of the output shaft.