Issued Patents All Time
Showing 1–12 of 12 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8926311 | Vibration system for concrete pipe making machines | — | 2015-01-06 |
| 7832703 | Apparatus and method for protecting lined concrete pipe during the manufacturing process | David Stoller | 2010-11-16 |
| 7083406 | Vibration system for concrete pipe making machines | David Stoller | 2006-08-01 |
| 6817589 | Apparatus and method for removing joint rings from cured concrete products | Ronald D. Schmidgall, David Stoller | 2004-11-16 |
| 5720993 | Collapsible core for concrete pipe making apparatus | — | 1998-02-24 |
| 5679279 | Collapsible core seam cover for concrete making apparatus | — | 1997-10-21 |
| 5587185 | Automated system for handling and cleaning concrete pipe-making components | Hartzell H. Schmidgall | 1996-12-24 |
| 4999965 | Spacer for double cage reinforcement wire mesh for concrete products | Galen G. Metzger | 1991-03-19 |
| 4989388 | Spacer for spacing reinforcing mesh wire from the form in the manufacture of concrete pipe and the like | Galen G. Metzger | 1991-02-05 |
| 4708621 | Concrete pipe making machine | Hartzell H. Schmidgall | 1987-11-24 |
| 4657498 | Apparatus for lining pipe | Hartzell H. Schmidgall | 1987-04-14 |
| 4578235 | Method for lining pipe | Hartzell H. Schmidgall | 1986-03-25 |