Patent ID: 7622690

Claim:
A movable contact made by an elastic thin plate metal, comprising: a conical circumferential edge in which a outer circumference edge of the elastic thin plate metal having a circular shape when seen from the upper side has an inclined surface; and a spherical surface-like section in which a part surrounded by the conical circumferential edge swells in an upward direction, wherein: when the spherical surface-like section is depressed, the spherical surface-like section elastically inverts while causing a stepwise feeling and, when the depression on the spherical surface-like section is cancelled, the spherical surface-like section elastically returns to have an original upwardly-swelling shape, both ends of the circular shape are cut by straight lines in parallel to each other to form two mutually symmetric straight edges having an identical distance to a center line of the circular shape, parts at which the cut straight edges intersect with the conical circumferential edge are chamfered to have a circular arc-shape to provide an oval shape or a race track-like shape, and a relation ((P 1 −P 2 )/P 1 ) between depression force (P 1 ) caused at the elastic inversion by the depression operation and depression force (P 2 ) at the elastic recovery ((P 1 −P 2 )/P 1 ) is set to be at least 40% or more.