Reciprocating power tool

Abstract

It is an object of the present invention to provide a useful technique for effectively reducing vibration in a reciprocating power tool with a simple structure. According to the present invention, a representative reciprocating power tool includes a motor, a tool bit, a slider, a motion converting mechanism and a counter weight. The tool bit performs a predetermined operation by reciprocating. The slider reciprocates to drive the tool bit. The motion converting mechanism converts a rotating output of the motor into a reciprocating movement of the slider. The counter weight is provided in the motion converting mechanism. Further, the counter weight reciprocates in a direction opposite to the reciprocating direction of the slider. The phase difference between the reciprocating movement of the slider and the reciprocating movement of the counter weight is set such that a time lag is provided between the instant when the slider reaches a top dead center and the instant when the counter weight reaches a bottom dead center. With such construction, timing for reducing the kinetic energy caused by the reciprocating movement of the slider can be optimized, taking into account a cutting resistance that the tool bit receives from the workpiece during operation.