Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4310315 | Tactile learning device for the handicapped | Daniel Frank, Jack Schaefer | 1982-01-12 |
| 4309575 | Apparatus for intercranial transmission of audio signals | Jack Schaefer, Daniel Frank | 1982-01-05 |