초록 ▼

It is an object of the invention to provide a technique for a reduction of an impact force cased by rebound of a tool bit after its striking movement in an impact power tool. The representative impact power tool includes a tool body, a hammer actuating member, a striker, a weight and an elastic elem

It is an object of the invention to provide a technique for a reduction of an impact force cased by rebound of a tool bit after its striking movement in an impact power tool. The representative impact power tool includes a tool body, a hammer actuating member, a striker, a weight and an elastic element. A reaction force is transmitted from the hammer actuating member to the weight and the elastic element is elastically deformed when the weight moves ward by the reaction to absorb the reaction force. The invention is characterized in that the mass of the weight is set to about 40% or more of the mass of the striker.

대표청구항 ▼

We claim 1. An impact power tool comprising:a tool body,a hammer actuating member that is disposed in a tip end region of the tool body and performs a predetermined hammering operation on a workpiece by reciprocating in its axial direction,a striker that performs a striking movement on the hammer ac

We claim 1. An impact power tool comprising:a tool body,a hammer actuating member that is disposed in a tip end region of the tool body and performs a predetermined hammering operation on a workpiece by reciprocating in its axial direction,a striker that performs a striking movement on the hammer actuating member by reciprocating in the longitudinal direction of the tool body,a weight configured such that a first portion of a reaction force is transmitted from the hammer actuating member to the weight either by:(1) direct contact between the hammer actuating member and the weight, or(2) via an intervening member made of hard metal, the intervening member being configured to transmit the first portion of the reaction force from the hammer actuating member to the weight,a first elastic element configured such that a second portion of the reaction force is transmitted from the hammer actuating member to the first elastic member either by:(1) direct contact between the hammer actuating member and the first elastic element, or(2) via an intervening member made of hard metal the intervening member being configured to transmit the second portion of the reaction force from the hammer actuating member to the first elastic element, anda second elastic element that elastically deforms when the weight is caused to move rearward from the reaction force transmitting position by the reaction force transmitted to the weight and pushes the second elastic element, thereby absorbing the reaction force,wherein the mass of the weight is set to about 40% or more of the mass of the striker, and the first portion of the reaction force is greater than the second portion of the reaction force.