| 5450932 |
Dashpots |
— |
1995-09-19 |
| 5318426 |
Brick imprinting apparatus |
David W. Hanson, Lloyd Barthel, James Barthel, Michael A. Lynch |
1994-06-07 |
| 4943219 |
Hollow core concrete extruder |
— |
1990-07-24 |
| 4893859 |
Concrete slab lifting clamp |
— |
1990-01-16 |
| 4644727 |
Strand chair for supporting prestressing cable and cross-mesh in elongated precast concrete plank |
David W. Hanson, Richard R. Koehn, Lonnie G. Fox |
1987-02-24 |
| 4628653 |
Insulated concrete panel |
— |
1986-12-16 |
| 4457682 |
Machine for casting concrete members |
David W. Hanson, Richard R. Koehn |
1984-07-03 |
| 4416842 |
Directed cracking in concrete panel manufacture |
Terrance W. Duffy |
1983-11-22 |
| 4398761 |
Device for lifting and tilting concrete panels |
David W. Hanson, Richard R. Koehn |
1983-08-16 |
| 4369153 |
Machine for casting concrete members |
David W. Hanson, Richard R. Koehn |
1983-01-18 |
| 4360333 |
Aggregate exposing machine |
Lonnie G. Fox, David W. Hanson |
1982-11-23 |