Patent attributes
An electric impact tool in which a rotating mass rotates in a forward direction to impact upon and transfer torque to an anvil, and rotates in a reverse direction opposite the forward direction in response to such impact. A direction sensor monitors the direction of rotation of the rotating mass, and a controller turns an electric motor on and off during respective forward and reverse rotation of the rotating mass. An energy storing mechanism may be used to absorb energy from reverse rotation of the rotating mass and release the absorbed energy to rotate the rotating mass in the forward direction. A controller may be used to store the angular position of the rotating mass upon each impact and turn off the motor prior to the following impact to avoid energizing the motor during stall.