JPS6484613A - Polarized solenoid - Google Patents

Abstract

PURPOSE:To improve the magnetic efficiency and to increase the dynamic sensitivity of the title solenoid by a method wherein the magnetic path containing no large magnetic reluctance is provided for excitation by the third yoke, and the attracting force when excitation is conducted is increased. CONSTITUTION:In the constitution in which a current is applied to a coil 51 and the N-pole of a permanent magnet 4 is connected, for example, to the first yoke 1, the upper and the lower end parts of a movable iron core 6 are excited into N-pole and S-pole respectively. The iron core 6 is moved to the side of the lowest limit by the repulsive force of the yoke 1 and the upper end part of the iron core 6, and the attracting force generated by the third magnetic path P3 starting from the iron core 6, passing through the third yoke 3, a fixed iron core 7, a void I2, and ending at the core 6, and the core 6 is supported at the lower limit position. At this point, a void of the prescribed distance is maintained between the lower end of the core 6 and the upper end of the core 7 by the energization of the energizing means so that they not come in contact with each other. As a result, attracting force is increased from one which was obtained before. As a result, the magnetic efficiency of the title solenoid can be improved, and its dynamic sensitivity can also be improved.