| Number | Name | Date | Kind |
|---|---|---|---|
| 4265500 | Berton | May 1981 | A |
| 4356531 | Marino et al. | Oct 1982 | A |
| 4530033 | Meggs | Jul 1985 | A |
| 6154361 | Anderson et al. | Nov 2000 | A |
| 6185109 | Koradia et al. | Feb 2001 | B1 |
| 6325472 | Tirrell et al. | Dec 2001 | B1 |
| Entry |
|---|
| Machinery's Handbook, 24th edition, 1992, ed. Robert Green, Industrial Press Inc., pp. 531-532 and 1240. |