| All Patents in class 451/375 |
Patents 1 -
15
of 39
      |
| Number | Date | Patentee | Title | Type |
| 141,760 | Aug. 12, 1873 | S.W. Card | Machines for milling twist-drills | metal threading machines |
| 183,798 | Oct. 31, 1876 | A.F. Champlin | Improvement in Tools for Sharpening Drills | bench or pedestal grinders |
| 201,449 | Mar. 19, 1878 | A.K. Rider | Drill Grinder | drill grinders |
| 230,715 | Aug. 03, 1880 | I.L. Penney | Grinding Twist Drills | tool grinders |
| 299,433 | May 27, 1884 | A. Coventry, W.F. Smith | Machinery for Grinding or Sharpening Drills | drill grinders |
| 407,577 | Jul. 23, 1889 | J.D. Cox, Jr. | Machine for back-clearing twist-drills | tool making machines |
| 425,839 | Apr. 15, 1890 | O.S. Walker | Twist-drill-grinding machine | sharpening machines |
| 428,426 | May 20, 1890 | J.H. Storey, H.J. Bamford | Machine for grinding twist or other drills | sharpening machines |
| 508,268 | Nov. 07, 1893 | J.S. Bancroft | Machine for Sharpening Drills | drill grinders |
| 607,306 | Jul. 12, 1898 | O.S. Walker | Twist-drill-grinding machine | drill grinders |
| 613,127 | Oct. 25, 1898 | W. Eames | Twist Drill Grinder | drill grinders |
| 614,092 | Nov. 15, 1898 | G.T. Eames | Drill-grinder | drill sharpening machines |
| 622,212 | Apr. 04, 1899 | R. Dutton | Twist-drill grinder | drill grinders |
| 630,536 | Aug. 08, 1899 | L.S. Heald, J.N. Heald | Drill-grinding machine | sharpening machines |
| 643,703 | Feb. 20, 1900 | H.P. White | Drill-grinding machines | drill sharpening machines |
