Patent attributes
An electric hand held pulse tool for performing tightening operations where torque is delivered in pulses to tighten screw joints. The pulse tool includes a bidirectional electric motor, an output shaft, a sensor for monitoring a parameter reflecting a delivered torque pulse, and a control unit for controlling the electric motor. The sensor provides information regarding the monitored parameter to the control unit. The control unit, during a tightening operation performed by the pulse tool in a first direction, controls the motor to provide at least one torque pulse on the output shaft in a second direction that is opposite to the first direction. The sensor monitors a parameter reflecting a delivered torque pulse on the output shaft in the second direction. The control unit also determines information about the nature and state of a joint, due to the torque pulse on the output shaft in the second direction.