| Number | Name | Date | Kind |
|---|---|---|---|
| 2582759 | Sass | Jan 1952 | |
| 2606675 | Jones | Aug 1952 | |
| 2730253 | Oswalt | Jan 1956 | |
| 3013684 | King et al. | Dec 1961 | |
| 3719296 | Larson, Jr. | Mar 1973 | |
| 4334820 | Homura | Jun 1982 | |
| 4403901 | Kopczynski | Sep 1983 |
| Number | Date | Country |
|---|---|---|
| 0180694 | May 1986 | EPX |
| 3217561 | Dec 1982 | DEX |
| 233353 | Feb 1986 | DEX |
| 2471334 | Jun 1981 | FRX |
| 2579187 | Sep 1986 | FRX |
| 1202398 | Aug 1970 | GBX |
| Entry |
|---|
| European Search Report/Application No. EP 87 30 7156. |