Patent attributes
It is an object of the invention to provide a technique for further improving the vibration reducing performance in a power impact tool that linearly drives a tool bit by using a swinging mechanism. According to the invention, a representative power impact tool is provided with a motor, a rotating shaft, a swinging member, a tool driving mechanism and a counter weight. The swinging member is supported by the rotating shaft to swing in the axial direction of the rotating shaft by rotation of the rotating shaft. The counter weight is disposed in a region higher than a lower end region of the swinging member in the vertical direction to intersect with the axis of the rotating shaft, and a lower end of the counter weight is connected to the lower end region of the swinging member. The counter weight extends upward from the connection between the counter weight and the swinging member and has a pivot point in the extending end portion, and when the swinging member swings, the counter weight is driven by the swinging member to rotate in the axial direction of the tool bit, thereby reducing vibration caused in the axial direction of the tool bit.