Rotational operation type switch

A rotational operation type switch, comprising:

• a frame;
• a rotational operation button rotatably supported on the frame for rotational operation;
• a switching contact mechanism disposed below the operation button to face the operation button;
• and
• an operation mechanism including a cam, and disposed between the operation button and the switching contact mechanism, to switch the switching contact mechanism in conjunction with the rotational operation of the operation button,
• wherein the switching contact mechanism includes a printed circuit board, a plurality of fixed contact electrodes disposed on the printed circuit board and spaced at a predetermined distance away from each other, and a movable contact having a disc spring shape and disposed bridging between the plurality of fixed contact electrodes,
• the movable contact deforms to contact with and separate from the plurality of fixed contact electrodes and switches an electrical connection between the plurality of fixed contact electrodes, and
• the operation mechanism includes an annular cam formed with a cam surface on a rear surface of the operation button to face the switching contact mechanism, the cam surface undulating in a circumferential direction of the operation button, and a push bar urged by a spring so that one end face thereof abuts against the cam surface and another end face thereof operates the switching contact mechanism.