| 摘要 |
PURPOSE:To simplify door opening and closing control by providing a permanent magnetic field on the upper surface of a door, installing an armature along the whole distance of a door movement area on the lower surface of a door upper frame and providing a good conductor brake disc on the armature against the permanent magnet. CONSTITUTION:An armature 20 consisting of a coil 21, a yoke 22 and a good conductor brake disc 23 is provided on the lower surface of an upper part frame of a door frame 6. Secondly, a magnetic field 1 consisting of a permanent magnet 11 and a yoke 12 is provided on the upper surface of a door 3. Thirdly, ac power is input in the coil 21, and when the phase of electric current is suitable, magnetic force of the permanent magnet 11 works in the forwarding direction of the magnetic field of the armature 20 and the door 3 is opened. Subsequently, when the input phase is not suitable, the door frame 6 is accelerated in the opposite direction, but it is braked as eddy current flows in the brake disc 23, and the door 3 is closed as magnetic force in the forwarding direction is generated at the next point. Consequently, it is possible to input electric power source at an optional phase, minitualize and improve maintainability without detecting the magnet position. |
