Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4828599 | Method for producing glass tubing of a narrowed diameter | Frederick Sachs | 1989-05-09 |
| 4818266 | Apparatus for producing glass tubing of a narrowed diameter | Frederick Sachs | 1989-04-04 |
| 4803718 | Hold detecting and control circuit for a key telephone system | James E. Neil, Christopher R. Caile | 1989-02-07 |