| Number | Date | Country | Kind |
|---|---|---|---|
| 1-18681 | May 1989 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| D186435 | Wilson | Oct 1959 | |
| D299392 | Faust | Nov 1973 | |
| 2230923 | Barry | Feb 1941 | |
| 2467604 | Tinnerman et al. | Apr 1949 | |
| 2869098 | Sauer | Jan 1959 | |
| 2932000 | Buchanan | Apr 1960 | |
| 4186987 | Pearce, Jr. et al. | Feb 1980 | |
| 4940423 | Aihara et al. | Jul 1990 |
| Number | Date | Country |
|---|---|---|
| 2915247 | Oct 1980 | DEX |
| 0807721 | Jan 1959 | GBX |
| Entry |
|---|
| Spring clip 19 on p. 5303 of IBM Tech. Disclosure Bulletin vol. 23 No. 12, 5-81. |