Patent ID: 8022326
Filing Date: 2011-09-20
Classification: H01H

Abstract:
1. A push switch comprising: a case made of insulating resin and having a surface facing upward; a center fixed contact exposed from the surface of the case; an intermediate fixed contact exposed from the surface of the case and located away from the center fixed contact; a peripheral fixed contact exposed from the surface of the case and located away from the center fixed contact and the intermediate fixed contact; a lower movable contact made of an elastic thin metallic plate, the lower movable contact including an upper movable contact made of an elastic thin metallic plate, the upper movable contact having substantially a dome shape having an upper surface and a lower surface, the upper surface of the upper movable contact having a convex shape protruding upward, the lower surface of the upper movable contact having a concave shape and facing the center fixed contact through the circular hole in the annular portion of the lower movable contact via a space between the upper movable contact and the center fixed contact, the outer edge of the upper movable contact being placed on the upper surface of the annular portion of the lower movable contact; an actuator movable in a predetermined direction in parallel with the surface of the case, the actuator including a cover including when the operating portion moves in the predetermined direction, the pressing portion of the actuator moves along the inclining surface of the inclining portion of the cover while causing the arm to deflect so as to press the upper surface of the upper movable contact downward, the third leg is placed on the peripheral fixed contact, the case has a rectangular shape having short sides in parallel with the predetermined direction and long sides longer than the short sides as seen from above, the first leg and the fourth leg of the first movable contact are symmetrical to each other with respect to a center of the annular portion as seen from above, the second leg and the third leg of the first movable contact are symmetrical to each other with respect to the center of the annular portion as seen from above, the first leg and the second leg of the first movable contact are symmetrical to each other with respect to a center axis which passes the center of the annular portion and which is parallel with the predetermined direction as seen from above, the first leg and the third leg of the first movable contact are located away from each other by an angular interval smaller than 90 degrees with respect to the center of the annular portion as seen from above, and the first leg, the second leg, the third leg, and the fourth leg of the lower movable contact are located within the width of the annular portion along the predetermined direction.