PURPOSE: To secure good dynamic sensitivity by making a base end side of an armature so as to perform its circular motion via a rocking lever being driven by a pushbutton.
CONSTITUTION: When a control element 21a of a pushbutton 21 is pushed, a lever part 21b is rotated clockwise with a fulcrum part 21c as the center, and since a free end 23 of a rocking lever 23 is rotated counterclockwise centering on the fulcrum part 23a by a pressing projection 21d, a base end 18b of an armature 18 is pushed down. When the fulcrum part 18b between this armature 18 and the lever 23 goes beyond a change point dependent upon the position of a fulcrum part 26a between an inner end 13a of a common terminal strip 13 and a compression spring 26, this spring 26 operates for open, and thereby a traveling contact 19 is dissociated from a normally closed fixed contact 17 by its snap action, then it comes into contact with a normally opened fixed contact 16, thus an interval between the common terminal strip 13 and a nor mally opened fixed terminal strip 14 is electrically closed. According to this constitution, the rate of variation is pressing force to an operating distance in and around an operation limit position becomes lessened so that good dynam ic sensitivity is thus securable.
NIWA TAKASHI
SANO TAKEZO
KATO ISAO
