To forcedly open nipper blades when the nipper blades do not return since an object to be cut is gnawed into the nipper blades or the like due to the insufficiency of the cutting ability of a nipper at the time of cutting the object to be cut by providing a return mechanism provided with a fluid pressure operated piston for opening an arm part.
When an operation button 31 is pressed, since a ball valve 5 opens an air passage 284 and compressed air enters an air cylinder part 30a, a piston 27 is advanced against a spring 29, a pair of the nipper blades 22 and 23 are closed by the engagement of arms 22a and 23a to a tapered cone 271 and the object S to be cut is cut. When the nipper blades 22 and 23 gnaw into the object S to be cut and can not be opened by the force of an opening spring 13, a return button 32 is pressed, the ball valve 5 on a lower side is opened and the compressed air is introduced inside an air cylinder 26. Thus, a cylindrical piston 37 is advanced and the outer arms 22b and 23b of this nipper are opened around a shaft pin 16 through an outer tapered cone 37a at a tip.
| WO/2004/082878 | POWER TOOL HEAD AND POWER TOOL |
SONOHARA TSUNETOSHI
AWATA HIROKI
