| Number | Name | Date | Kind |
|---|---|---|---|
| 3081885 | Carlzen | Mar 1963 | |
| 3523316 | Alexander | Aug 1970 | |
| 3851359 | Escholz | Dec 1974 | |
| 4042090 | Hasebe et al. | Aug 1977 | |
| 4058217 | Vaughn et al. | Nov 1977 | |
| 4182030 | Mullins | Jan 1980 | |
| 4248389 | Thompson et al. | Feb 1981 |
| Entry |
|---|
| Manufacturing Engineering, vol. 85, No. 1, Jul. 1980, p. 56. |