| All Patents in class 451/375 |
Patents 1 -
15
of 50
      |
| Number | Date | Patentee | Title | Type |
| 104,982 | Jul. 05, 1870 | S.A. Morse | Improvement in grinding-rest for twist-drills | drill grinders |
| 141,760 | Aug. 12, 1873 | S.W. Card | Machines for milling twist-drills | making drills and augers |
| 153,401 | Jul. 21, 1874 | C. Van Haagen | Improvement in machines for sharpening twist-drills | drill grinders |
| 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 |
| 388,784 | Aug. 28, 1888 | F. Mossberg | Twist-drill-grinding attachment | drill grinders |
| 389,095 | Sep. 04, 1888 | F. Mossberg | Twist-drill-grinding attachment | 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 | drill grinders |
| 428,426 | May 20, 1890 | J.H. Storey, H.J. Bamford | Machine for grinding twist or other drills | drill grinders |
| 497,095 | May 09, 1893 | T. Hall | Drill-grinder | drill grinders |
| 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 |
