| All Patents in class 475/320 |
Patents 1 -
6
of 6
      |
| Number | Date | Patentee | Title | Type |
| 144,499 | Nov. 11, 1873 | A. Betts | Devices for Changing the Speed of Machinery | industrial machine speed and direction changing mechanisms |
| 252,537 | Jan. 17, 1882 | J. Stewart | Speed Gearing | industrial machine speed and direction changing mechanisms |
| 715,078 | Dec. 02, 1902 | H.F. Jeffs | Changeable Speed Gear | industrial machine speed and direction changing mechanisms |
| 2,544,061 | Mar. 13, 1951 | E.T. Barnett | Speed change driving head for power-driven machine | drill presses |
| 2,848,908 | Aug. 26, 1958 | J.C. Hollis | Planetary Speed Change Transmission | metalworking power transmission |
| 3,055,236 | Sep. 25, 1962 | L.R. Born, Jr. | Planetary gear pulley and control means | metalworking power transmission |
