| All Patents in class 451/209 |
Patents 1 -
10
of 16
      |
| Picture | Number | Date | Patentee | Title |
| | 79,610 | Jul. 07, 1868 | J.B. Tarr | Machine for Polishing Spherical Shot and Shells |
| | 1,176,180 | Mar. 21, 1916 | J.J. Thacher | Grinding-Machine |
| | 1,264,930 | May 07, 1918 | L.R. Heim | Roll Grinding Machine |
 | 1,483,748 | Feb. 12, 1924 | F.C. Sanford | Grinding Machine |
| | 1,611,135 | Dec. 14, 1926 | F.C. Sanford | Grinding Machine |
| | 1,683,974 | Sep. 11, 1928 | L.R. Heim | Grinding Apparatus |
| | 1,692,834 | Nov. 27, 1928 | L.R. Heim | Art and Apparatus for Producing Ground Articles |
| | 1,707,708 | Apr. 02, 1929 | J.E. Caster | Process for the Production of Spherical Articles |
| | 1,722,386 | Jul. 30, 1929 | C.H. Norton | Centerless Grinding Machine |
| | 1,722,387 | Jul. 30, 1929 | C.H. Norton | Centerless Grinding Machine |
