| Number | Date | Country | Kind |
|---|---|---|---|
| 3715145 | May 1987 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2153242 | Dreyfuss | Apr 1939 | |
| 2775184 | Pipes | Dec 1956 | |
| 3305168 | Ramniceanu | Feb 1967 | |
| 4392192 | Steadman | Jul 1983 | |
| 4656926 | Bauer et al. | Apr 1987 | |
| 4664023 | Miyadera et al. | May 1987 | |
| 4734918 | Bauer et al. | Mar 1988 |
| Number | Date | Country |
|---|---|---|
| 2814627 | Apr 1979 | EPX |
| 2930769 | Jan 1981 | EPX |
| 3535881 | May 1983 | DEX |
| 3317807 | Oct 1985 | DEX |
| Entry |
|---|
| Patent Abstracts of Japan, Band 10, Nr. 349 (M-538) [2405], Nov. 26, 86; &P-A-61 149 734 (Matsushita Electric Ind. Co., Ltd) 08-07-1986. |