Electronic calculator with switches in solid V- and U-shaped groups

摘要

In a hand-operated electronic calculator, a switchboard having push-button switches for digits and symbols, every two or more switches combined into V, or U, or square shaped groups either above the surface or recessed for receiving fingertips and actuated along two or more directions. Switch groups are arranged at finger locations, each group of switches being assigned to a certain finger, two or more groups to active fingers, and a group can be at a perpendicular direction to the other four fingers for thumb operating.