| Number | Name | Date | Kind |
|---|---|---|---|
| 2091139 | Crowell | Aug 1937 | |
| 2121439 | Menzel | Jun 1938 | |
| 2904870 | Hillberg | Sep 1959 | |
| 5059110 | Allison et al. | Oct 1991 | |
| 5297772 | Stefanick | Mar 1994 | |
| 5409193 | Baxter | Apr 1995 |
| Number | Date | Country |
|---|---|---|
| 508048 | Sep 1920 | FRX |
| 630230 | Mar 1963 | FRX |
| 2556511 | Jun 1977 | DEX |
| 856809 | Aug 1981 | SUX |
| Entry |
|---|
| Illustration entitled "Mold Box Assembly, 6 Block Machine, 8 x 8 x 16" Columbia Machine 1994. |