| 摘要 |
PURPOSE: To detect the full-open and full-closed positions of the window in a powered skylight system surely with no erroneous recognition at low cost. CONSTITUTION: The powered skylight system for opening/closing the window by driving a DC motor 1 comprises means 3 for extracting the ripple components superposed on the current waveform during rotation of the DC motor, means 7 for determining presence of the ripple component, and a control means 8 for deciding that the rotation of DC motor stopped at a moment when the presence of ripple component is not determined and interrupting the drive power supply to the DC motor. |
