![]() | |||
| Home| FAQ | Search:Advanced|Person|Company| Type|Class | Login | |
| Quick search: | ||
| Patents for Fred E. Birtch | |||||
| Number | Date | Patentee | Title | Type | |
| 2,978,843 | Apr. 11, 1961 | B.H. Johnson, F.E. Birtch | Apparatus for Grinding Double-Enveloping Worm Elements | gear grinding machines | |