PROXIMITY SWITCH

PURPOSE: To eliminate malfunction so as to improve reliability of a proximity switch by storing two permanent magnets whose similar polarity poles face each other, in a magnet assembly to be detected by arranging bias magnet of a lead switch assembly of 2 pieces in one body with their similar polarity of 2 magnetic poles facing to each other. CONSTITUTION: Each lead switch 1 allows each bias magnet 2 to be arranged in its proximity to be embraced therein. 2 pieces of this switch 1 are used so that two magnets 2 may be assembled in the direction in which the same pole plate face each other so that the switch 1 may be in its normally closed state so as to form a lead switch assembly 3. In addition, since AND is applied in view of electric circuits, in order to place two switches 1 in open position simultaneously, it is required to arrange a magnet assembly 5 to be detected under such condition that magnets 4 to be detected are arranged to same pole plates face to each other. Therefore, even though any external permanent magnet passes between the assembly 3 and the assembly 5, any erroneous action taking place in the conventional product may not take place.