|
| US4207443 | 9 août 1978 | 10 juin 1980 | Mikado Precision Industries Ltd. | Key-operated switch and an assemblage of such switches for electronic desk calculators or the like |
| US4264797 | 21 janv. 1980 | 28 avr. 1981 | W. H. Brady Co. | Elongated key membrane switch |
| US4287394 | 25 janv. 1979 | 1 sept. 1981 | Wilhelm Ruf KG | Keyboard switch assembly with printed circuit board |
| US4423464 | 13 avr. 1981 | 27 déc. 1983 | Alps Electric Co., Ltd. | Variable capacitance type push-button switch |
