Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4837976 | Window balance spring cover friction system | Norman R. Westfall | 1989-06-13 |
| 4800680 | Cord guide system for sash balance | Norman R. Westfall, John I. Habbersett, Brian S. Dense | 1989-01-31 |