| Number | Name | Date | Kind |
|---|---|---|---|
| 1812942 | Gaines | Jul 1931 | A |
| 4069983 | Muramatsu et al. | Jan 1978 | A |
| 4108388 | Schär | Aug 1978 | A |
| 4552314 | Noguchi et al. | Nov 1985 | A |
| 4942730 | Morrison | Jul 1990 | A |
| 5676322 | Stahlecker | Oct 1997 | A |
| 5738290 | Straaten et al. | Apr 1998 | A |
| Number | Date | Country |
|---|---|---|
| 535711 | May 1973 | CH |
| 4213859 | Nov 1992 | DE |
| 4312823 | Oct 1993 | DE |
| 4438501 | May 1996 | DE |
| 19644593 | Apr 1998 | DE |
| 0394885 | Oct 1990 | EP |
| 0417849 | Mar 1991 | EP |
| 1470450 | Apr 1977 | GB |
| Entry |
|---|
| German Patent Office Search Report, Nov. 12, 1999. |
| Abstract of Japan (3-143874) Sep. 12, 1991 vol. 15/No. 362. |