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.