| Number | Name | Date | Kind |
|---|---|---|---|
| 2663660 | Layte | Dec 1953 | A |
| 3692184 | Miller, Jr. et al. | Sep 1972 | A |
| 3871851 | Neumann | Mar 1975 | A |
| 3999964 | Carr | Dec 1976 | A |
| 4885015 | Goulet et al. | Dec 1989 | A |
| 4963171 | Osendorf | Oct 1990 | A |
| 5167740 | Michaelis et al. | Dec 1992 | A |
| 5273564 | Hill | Dec 1993 | A |
| 5599366 | Hassenboehler, Jr. et al. | Feb 1997 | A |
| 5599448 | Spearman | Feb 1997 | A |
| 5743927 | Osendorf | Apr 1998 | A |
| 6030428 | Ishino et al. | Feb 2000 | A |
| 6156086 | Zhang | Dec 2000 | A |
| 6336948 | Inoue et al. | Jan 2002 | B1 |
| 6464745 | Rivera et al. | Oct 2002 | B2 |