| All Patents in class 451/138 |
Patents 1 -
7
of 7
      |
| Number | Date | Patentee | Title | Type |
| 222,736 | Dec. 16, 1879 | G. Richards | Machines for Grinding the Sector of Circles | |
| 508,268 | Nov. 07, 1893 | J.S. Bancroft | Machine for Sharpening Drills | drill grinders |
| 529,013 | Nov. 13, 1894 | B.F. Barnes | Milling Machine | milling machines |
| 630,325 | Aug. 08, 1899 | H.W. Cheney | Bevel-gear-generating machine | gear making machines |
| 646,397 | Mar. 27, 1900 | W.H. Thorne, J.S. Bancroft | Grinding-Machine | tool grinders |
| 704,348 | Jul. 08, 1902 | J.N. Lapointe | Grinding-machine | drill sharpening machines |
| 774,030 | Nov. 01, 1904 | L.B. Benton | Grinding Machine | tool grinders |
