Abstract: An operation input device includes a base including at least four elastic engagement receiving portions raised at a periphery of a center thereof; a print substrate configured to be stacked and integrated on the base; an annular operation plate mounted on push button switches of the print substrate and configured to prevent slip-out; an operation dial mounted on the annular operation plate on an axial center; and a fixing tool configured to be inserted to a fit-in hole of the operation hole and engage with at least two elastic engagement receiving portions of the base at an edge on a lower side and with an inner peripheral edge of the operation dial.

Abstract: An information input device includes a flexible print substrate including first, second and third installation units, first and second coupling units coupling the first installation unit with the second installation unit and the second installation unit with the third installation unit respectively, so that the first, second, and third installation units are extended along a same axis, the first, the second, and the third installation units being folded to a bellows form and integrated through the first and the second coupling units, a sensor sheet, an operation plate configured to be pushably installed by means of the sensor sheet on an upper surface of the third installation unit, a push button configured to be pushably assembled through an operation hole formed in the operation plate; and a dome-shaped movable contact arranged on the second installation unit.