HAND TOOL

PURPOSE: To shorten the length of a hand tool by composing a contact sensing device of arm type rotatable levers with axes intersecting a tool axis, and constituting each lever in such a way that one arm of the lever collides with a control element and that the other arm is put in linkage action with a sensor. CONSTITUTION: An anvil 3 transmits impact force transmitted from an impact piston 4, to a tool 5. An insert shaft 5a of the tool 5 is inserted in a guide hole 1a, and the free end of the insert shaft 5a is protruded into a differential area of the anvil 3. Balls 21, 23 are opposedly pushed into long and narrow recesses 5d, 5f formed at the side face of the tool 5. This push-in is performed by compression springs 31, 32 acting upon lever arms 25b, 26b on the far side from the balls 21, 22. The rotation of these lever arms 25b, 26b causes the opposite direction rotation of the other arms 25a, 26a integral with the arms 25b, 26b, that is, the arms 25b, 26b on the far side from the balls 21, 22 are rotated outward so as to enter slit-like through openings 17g, 17h.