| All Patents in class 474/28 |
Patents 1 -
7
of 7
      |
| Picture | Number | Date | Patentee | Title |
| | 1,035,860 | Aug. 20, 1912 | C.M. Conradson | Speed Variator |
| | 1,545,638 | Jul. 14, 1925 | H.C. Clay | Automatic Speed Regulation |
| | 2,112,141 | Mar. 22, 1938 | H.C. Clay | Hydraulic Control for Variable Speed Transmissions |
 | 2,256,114 | Sep. 16, 1941 | D. Heyer | Variable speed drive with multiple belts |
| | 2,295,161 | Sep. 08, 1942 | H.C. Clay | Hydraulic Control Mechanism |
| | 2,306,541 | Dec. 29, 1942 | H.C. Clay | Floating Hydraulic Control |
| | 2,714,313 | Aug. 02, 1955 | W.E. Gerbing | Variable pitch pulley |
