 
                 Patent Grant
 Patent Grant
                     4961581
 4961581
                    | Number | Date | Country | Kind | 
|---|---|---|---|
| 8724931 | Oct 1987 | GBX | 
| Number | Name | Date | Kind | 
|---|---|---|---|
| 3163423 | Jackson | Dec 1964 | |
| 3733076 | Ohki | May 1973 | |
| 4134592 | Pullman | Jan 1979 | |
| 4188036 | Jones-Fenleigh | Feb 1980 | |
| 4705276 | Kastle et al. | Nov 1987 | |
| 4743029 | Consolatore et al. | May 1988 | 
| Number | Date | Country | 
|---|---|---|
| 2206173 | Feb 1971 | DEX | 
| 289729 | Dec 1950 | FRX | 
| 1338212 | Jan 1972 | GBX | 
| 2130413 | Oct 1983 | GBX | 
| 2157047 | Apr 1984 | GBX | 
| Entry | 
|---|
| European Search Report of EP88,30,9474 Completed 12/3/90. |