| Number | Name | Date | Kind |
|---|---|---|---|
| 1491675 | Conklin | Apr 1924 | |
| 1568880 | Conklin | Jan 1926 | |
| 2166439 | Johnson | Jul 1939 | |
| 2824685 | Patton | Feb 1958 | |
| 3655121 | Ward | Apr 1972 | |
| 3937492 | Biron | Feb 1976 | |
| 3986662 | Luftig | Oct 1976 | |
| 4368903 | Jones | Jan 1983 | |
| 4429827 | Murray | Feb 1984 | |
| 4682793 | Walz | Jul 1987 | |
| 5104036 | Rutkowski et al. | Apr 1992 | |
| 5183203 | Sanders | Feb 1993 | |
| 5190210 | Walz | Mar 1993 | |
| 5213258 | Kim | May 1993 | |
| 5271553 | Kim | Dec 1993 | |
| 5316208 | Petkovsek | May 1994 | |
| 5346124 | Chess | Sep 1994 | |
| 5501393 | Walz | Mar 1996 | |
| 5507526 | Petkovsek | Apr 1996 | |
| 5752647 | Schubert et al. | May 1998 |
| Entry |
|---|
| "Commercial Ferrarelli, Inc. Return Receipt envelope, photocopy, admitted prior art," No Date. |