Patent ID: 8485273
Filing Date: 2013-07-16
Classification: B25B

Abstract:
1. An electric assembly device for tightening threaded fasteners, comprising: a housing; a variable speed rotation motor; an output shaft connected to the motor and rotatable about a rotation axis; coupling means provided on the output shaft for coupling the output shaft to a threaded fastener to be tightened; wherein the housing is arranged to be manually supported by an operator and is angularly displaceable relative to the rotation axis; determining means for determining an angular displacement of the housing relative to the rotation axis during tightening of the threaded fastener; and a control unit which controls a rotation speed of the motor during tightening in relation to the determined angular displacement of the housing; wherein the rotation speed of the motor is arbitrarily determinable by the operator by angularly displacing the housing relative to the rotation axis in one of a rotation direction of the output shaft and a direction opposite to the rotation direction of the output shaft, to thereby correspondingly determine a tightening speed of the fastener; and wherein the control unit is configured to: