Patent ID: 8440928

Claim:
A rotary electronic component comprising: a rotor including a flange with a first face and a second face, a plurality of grooves being formed radially on the first face of the flange; a plate spring with a ring shape in a top view, the plate spring including: a plurality of resilient arms with an arc shape in the top view, the resilient arms having a shape inclining downward, at least one of the resilient arms resiliently contacting the first face of the flange; and a flat part provided between adjacent resilient arms of the resilient arms; an upper member with a bottom face covering the plate spring and the first face of the flange; and a rotary element unit outputting a signal in response to rotation of the rotor; wherein the upper member retains the flat part of the plate spring such that the flat part can be attached to and detached from the bottom face of the upper member while preventing the plate spring from rotating responsive to rotation of the rotor; and wherein a spring constant of the resilient arms and a shape of the flat part are set to achieve a state such that the resilient arms bend and at a same time the flat part is partially released from the bottom face of the upper member when the resilient arms go over a position between adjacent grooves of the plurality of grooves formed on the first face of the flange.