Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 10350393 | Checker balloon winding machine | David M. Graves, William E. Parmentier, Robert G. Lerdahl, Jo Ann Kelly | 2019-07-16 |
| 9643235 | Checker balloon winding machine | David M. Graves, William E. Parmentier, Robert G. Lerdahl, Jo Ann Kelly | 2017-05-09 |
| 8673200 | Checker balloon winding machine | David M. Graves, William E. Parmentier, Robert G. Lerdahl, Jo Ann Kelly | 2014-03-18 |
| 8236223 | Checker balloon winding machine | David M. Graves, William E. Parmentier, Robert G. Lerdahl, Jo Ann Kelly | 2012-08-07 |