Casing of electronic calculators
AssigneeSharp Kabushiki Kaisha
InventorAkira Tanimoto
Life of this patent
Estimating the term…
Abstract
Wiring patterns and key contact patterns are directly formed on an inner surface of a casing of an electronic calculator. A printed board or a substrate can be eliminated by mounting electrode elements on the inner surface of the casing to establish electrical connection with the wiring patterns formed on the inner surface of the casing, thereby enabling the reduction of size, especially thickness, of the electronic calculator.
Claims17
An electronic calculator comprising:
- a. an upper cover;
- b. wiring patterns directly formed on an inner surface of the upper cover;
- c. a display unit mounted on the inner surface of the upper cover and electrically connected to the wiring patterns;
- d. a computation circuit unit mounted on the inner surface of the upper cover and electrically connected to the wiring patterns;
- e. key contact patterns formed directly on the inner surface of the upper cover and electrically connected to the wiring patterns;
- f. key switches electrically associated with the key contact patterns;
- and
- g. a bottom and side cover fixed to the upper cover.
An electronic calculator comprising an upper cover and a bottom cover, key contact patterns and wiring patterns formed directly on the inner surface of the bottom cover, a computation circuit unit and a display unit mounted on the inner surface of the bottom cover, the computation circuit unit and the display unit being electrically connected to said key contact patterns by said wiring patterns, and a keyboard unit containing a plurality of key contacts mounted on the bottom cover and extending over the key contact patterns between the upper cover and the bottom cover, said key contacts being adapted to contact corresponding key contact patterns when the key contacts are depressed for information entry, said keyboard unit further comprising a plurality of apertures for receiving said key contacts and couplers extending from the bottom surface of the keyboard unit, said bottom cover being provided with through holes which correspond in position to that of said couplers, said couplers extending through said through holes for coupling the keyboard unit with the bottom cover.
An electronic calculator comprising an upper cover and a bottom cover, key contact patterns and wiring patterns formed directly on the inner surface of the upper cover, a plurality of key switches slidably extending through said upper cover from the outside to the inside thereof, said key switches provided with key contact means, said key contact means being biased for contact with said key contact patterns, wiring patterns formed directly on the bottom cover, electronic elements mounted on the bottom cover and electrically connected to said wiring patterns and means for providing an electrical connection between the wiring patterns on the upper cover and the wiring patterns on the bottom cover.
An electronic calculator comprising an upper cover and a bottom cover, key contact patterns and wiring patterns formed directly on the inner surface of the bottom cover, a computation circuit unit and a display unit mounted on the inner surface of the bottom cover, the computation circuit unit and the display unit being electrically connected to said key contact patterns by said wiring patterns, a plurality of key switches mounted on the upper cover and slidably extending through the upper cover from the outside to the inside thereof and provided with key contact means for contacting corresponding key contact patterns when the key switches are depressed for information entry and bias means for causing said key contact means being brought into contact with said key contact patterns by the manual depression of the key switches.
Dependencies are inferred from the claim text.