| 主权项 |
1. A torque driver comprising:
a case so as to serve as a hand grip section; a torque limiter section disposed in the case; a main shaft to which a tightening force applied to the case is transmitted through the torque limiter section; a coupler fixed at a tip portion of the main shaft; and a bit attached to a tip portion of the coupler, wherein the case is rotated relative to the main shaft when a tightening torque on a screw engaged with the bit reaches a torque value set in the torque limiter section to activate the torque limiter section, wherein the torque driver comprises: a marker extending from an inside of the coupler to a tip portion of the bit along a side surface of the bit; and a marker activating section that allows the marker to move forward by utilizing rotation of the case relative to the main shaft so that a tip portion of the marker contacts the screw to perform marking thereon, wherein the marker activating section includes: a fixed section fixed to the case; a moving member disposed to be opposed to the fixed section and to be capable of moving in an axial direction and incapable of rotating about an axis with respect to the main shaft, the moving member moving forward in the axial direction so as to move the marker forward; and a plurality of permanent magnets disposed on opposing surfaces of the fixed section and the moving member with phases shifted from one another about the axis, the plurality of permanent magnets disposed on one of the opposing surfaces having magnetic poles same as those of the plurality of permanent magnets disposed on another of the opposing surfaces, and wherein at a rotational position at which the torque value is reached in the fixed section, the plurality of permanent magnets disposed on the fixed section is positioned directly facing the plurality of permanent magnets disposed on the moving member opposed to the fixed section. |
