Abstract: A rotating range restricting mechanism that restricts the rotating range of a rotating body rotatable 360 degrees or more with respect to a supporting body includes: a swing member rotatably attached to the supporting body; a first restricting member abutting the swing member to restrict the swing range of one end of the swing member; a second restricting member abutting the swing member to restrict the swing range of the other end of the swing member; an engaging member fixed to the rotating body which engages with the swing member to allow the swing member to swing between a first restricting position and a second restricting position; a first magnetic holding mechanism that holds the swing member in the first restricting position with a magnetic attraction force; and a second magnetic holding mechanism that holds the swing member in the second restricting position with a magnetic attraction force.