Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4854827 | Sanitary pump station | James A. Sigler, Richard W. Sprang, Richard R. Lewellen, Mark W. Geis | 1989-08-08 |
| 4819279 | Vacuum toilet system | James A. Sigler, Richard W. Sprang, Ronald J. Bailey | 1989-04-11 |