| All Patents in class 451/279 |
Patents 1 -
6
of 6
      |
| Number | Date | Patentee | Title | Type |
| 59,950 | Nov. 27, 1866 | J. Borthwick | Improved Machine for Sharpening Saws | annular saws |
| 78,909 | Jun. 16, 1868 | W.H. Wilson, G.P. York | Sharpening Mowing-Machine Knives | sharpening machines |
| 421,896 | Feb. 25, 1890 | H. Bergstrom | Machine for holding and sharpening insertible saw-teeth | tool making machines |
| 575,737 | Jan. 26, 1897 | A.S. Robinson | Machine for grinding knives of cutter-bars | sharpeners |
| 1,382,794 | Jun. 28, 1921 | M.L. Luebben | Machine for Sharpening Safety Razor Blades | household tools |
| 6,676,495 | Jan. 13, 2004 | M.B. Siemers, E. Irwin, L.G. Lee, L. Sevack | Power sharpening system | |
