| 摘要 |
<p>PURPOSE:To stop the rotation of a steel plate with precision, by providing a magnetic flux leakage preventing plate and a rotational inertia preventing part and making the attractive force of the steel plate constant. CONSTITUTION:In the case of rotating thin steel plate 58, magnetic flux leakage preventing plate 37, which sandwiches thin steel plate 58, passes a magnetic flux in excess of the magnetic capacity of thin steel plate 58 by dividing it. Hence, the magnetic path is divided into magnetic flux 61, which passes from iron core 52 to thin steel plate 58 and yoke 53, and magnetic flux 62, which passes from iron core 52 to thin steel plate 58, leakage preventing plate 37 and yoke 53, and there is no change in the magnetic flux resistance. For this reason, the steel plate attracting force of electromagnet 34 remains constant without decrease. As a result, thin steel plate 58 is rotated at a fixed rotational angle with a fixed rotational force being sandwiched by electromagnet 34 and magnetic flux leakage preventing plate 37. Next, air is supplied to electromagnet 34 from an air- supply device via conduit 39. This increases the pressure in air chamber 55. As a result, steel plate contrl plate 57 is pushed up, which, together with leakage preventing plate 37, sandwiches thin steel plate 58 and increases its frictional resistance, and thereby prevents thin steel plate 58 from over-rotation.</p> |
