1. Field of the Invention
The present invention relates to electronic equipment having a key input function such as an electronic desk-top calculator.
2. Description of the Prior Art
In a prior art key input device for a desk-top calculator or the like, a pair of input stationary contacts and a movable contact made of conductive rubber located to face the pair of stationary contacts are provided, and the movable contact is moved down by a vertically movable key top to bridge-short the pair of stationary contacts.
Such a structure, however, needs a number of parts such as the key top and the conductive rubber member, and because of the thicknesses of those parts a thin structure desirable for a portable desk-top calculator is not attained.
Further, because of the input system in which the stationary contacts are bridge-shorted by the conductive rubber member, the circuit pattern is complex, the number of manufacturing steps for the printed circuit board is large and a double-sided printed circuit board must be used.
USPTO Backgrounds
USPTO Backgrounds