Patent ID: 7510085

Claim:
An apparatus for discriminating a kind of a sheet material, comprising: a substrate having a recessed portion; a press member situated so that a sheet material can be deflected using the recessed portion; a roller which holds the press member, wherein the roller holds the press member at a distance from the substrate when the sheet material is set in the substrate, and moves the press member to a position near the recessed portion when the sheet material is pressed; an elastic support member for supporting the press member such that the sheet material situated to cover the recessed portion is pressed by the press member against the elastic support member; a deformation amount sensor, having a piezoelectric member provided on the elastic support member, for detecting information corresponding to a deformation amount of the sheet material; and unit for discriminating a kind of the sheet material on basis of the information on the deformation amount of the sheet material detected by the sensor, wherein the press member is situated outside the recessed portion, the elastic support member is situated inside the recessed portion, and the elastic support member is deformed on the basis of pressing the elastic support member via the sheet material by the press member.