| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a fastening tool that screws together and fastens a pin 50 having a tool engagement hole on the tip end surface thereof and a nut 60 which screws onto the pin by relatively rotating the pin and the nut, and that as the fastening work progresses, firmly holds the tip end part which engages with the pin at a location closer to the pin. <P>SOLUTION: As shown in Figs.8(a)-8(b), even though a key wrench 38 is pressed backward as the pin 50 is screwed into the nut 60, a key wrench holder 31 remains in a state of contact with the nut to hold the key wrench not to be rotated at a position close to the nut by a hexagonal hole 31c of the tip part of the key wrench holder. After the pin has been completely screwed into the nut, the nut is twisted off at a weak part 62. The further the pin is screwed into the nut, the key wrench holder holds the key wrench at a location closer to the pin, which keeps small a torsional deformation amount of the tip end part of the key wrench, and thus surely engage the key wrench and the pin together. Thus, in the final stage of the fastening work, the twist-off type nut, which requires large torque, is completely twisted off. <P>COPYRIGHT: (C)2012,JPO&INPIT |
