Issued Patents All Time
Showing 1–7 of 7 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4611307 | Function analyzing | Roy W. Reach, David Shapiro | 1986-09-09 |
| 4389642 | Digital matrix switching | — | 1983-06-21 |
| 4381554 | Calculator for storing source data and evaluating numerical answers to problems | Roy W. Reach, David Shapiro | 1983-04-26 |
| 4309761 | Calculator for evaluating numerical answers to problems | Roy W. Reach, David Shapiro | 1982-01-05 |
| 4198684 | Electronic calculator with keyboard-controlled unary function capability | Roy W. Reach, David Shapiro | 1980-04-15 |
| 4193600 | Cribbage scoring device | Roy Armstrong | 1980-03-18 |
| 4191848 | Teletypewriter motor controlling | — | 1980-03-04 |