Patent ID: 9116525
Filing Date: 2015-08-25
Classification: F01L,F02B,G05D

Abstract:
1. A reference angle detecting device comprising: a control shaft connected to a controlled object in order to control an angle of the controlled object; a worm wheel connected to the control shaft so as to cause the control shaft to rotate about an axial center thereof; a worm gear that meshes with the worm wheel; an electric motor for rotating the worm gear; a controller that controls the electric motor; a stopper disposed on a motion track of the worm wheel in order to restrict a rotatable range of the control shaft; and an angle sensor capable of detecting a rotation angle of the control shaft, wherein the stopper includes a spring member that is elastically deformable in an operation direction of the worm wheel, and the controller drives the electric motor to operate so that the worm wheel comes to face the stopper, and stores as a reference angle a rotation angle at a time point when a change rate of the rotation angle detected by the angle sensor during drive of the electric motor changes from a value equal to or higher than a predetermined threshold to a value less than the threshold.