| All Patents in class 451/252 |
Patents 1 -
11
of 11
      |
| Number | Date | Patentee | Title | Type |
| 1,445,875 | Feb. 20, 1923 | R.W. Ellingham, C.E. Van Norman | Grinding machine | vehicle mechanic |
| 1,659,220 | Feb. 14, 1928 | C. Booth, C.O. Smith | Centerless Grinding | grinding machines |
| 1,816,171 | Jul. 28, 1931 | C. Booth | Valve Grinder | grinding machines |
| 1,938,764 | Dec. 12, 1933 | H. Fritschi, F.S. Haas | Grinding Machine | grinding machines |
| 1,949,345 | Feb. 27, 1934 | H.H. Asbridge | Grinding or abrading machine | |
| 2,120,198 | Jun. 07, 1938 | R.G. Anderson, J.Y. Blazek | Valve grinder | vehicle mechanic |
| 2,136,188 | Nov. 08, 1938 | L. Spraker, G.R. Gagne | Valve Refacing Device | valve grinding tools |
| 2,746,758 | May 22, 1956 | G.S. Haviland, A.M. Stoner | Chucks | metal lathe chucks |
| 3,378,960 | Apr. 23, 1968 | W.B. Seidel | Machine Tool Workpiece Driving Mechanism | cylindrical grinders |
| 4,987,701 | Jan. 29, 1991 | M.H. Humbert | Endless belt valve grinder | valve and seat maintenance |
| 5,337,521 | Aug. 16, 1994 | D. Heyl, D.M. Terpstra | Valve grinder | valve and seat maintenance |
