| Number | Date | Country | Kind |
|---|---|---|---|
| 8-134030 | May 1996 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3493922 | Laas | Feb 1970 | |
| 4600087 | Tsuji | Jul 1986 | |
| 4711324 | Schroder | Dec 1987 | |
| 4718520 | Schroder | Jan 1988 | |
| 4792019 | Bittar et al. | Dec 1988 | |
| 4804069 | Bittar et al. | Feb 1989 | |
| 4836336 | Schroder | Jun 1989 | |
| 4846311 | Thangavalu | Jul 1989 | |
| 4847728 | Youla | Jul 1989 | |
| 4870334 | Iwawa et al. | Sep 1989 | |
| 4915197 | Schroder | Apr 1990 | |
| 4939634 | Schroder | Jul 1990 | |
| 4979594 | Begle et al. | Dec 1990 | |
| 4991694 | Friedli | Feb 1991 | |
| 5065846 | Schroder | Nov 1991 | |
| 5086883 | Schroder | Feb 1992 | |
| 5092431 | Schroder | Mar 1992 | |
| 5183981 | Thangavelu | Feb 1993 | |
| 5192836 | Schroder | Mar 1993 | |
| 5300739 | Bittar | Apr 1994 | |
| 5305198 | Schroder et al. | Apr 1994 | |
| 5317114 | Pullela et al. | May 1994 | |
| 5382761 | Amano | Jan 1995 | |
| 5460245 | Bittar | Oct 1995 | |
| 5480005 | Bittar | Jan 1996 | |
| 5612519 | Chenais | Mar 1997 |
| Entry |
|---|
| R.S. Phillips, "Electronic Lifts", Third Edition, 1951, pp. 254-256, 1951. |