| All Patents in class 91/445 |
Patents 1 -
10
of 14
      |
| Picture | Number | Date | Patentee | Title |
 | 50,320 | Oct. 10, 1865 | J.M. Albertson | Improvement in cut-off valves |
 | 276,076 | Apr. 17, 1883 | W.H. Ridgway | Elevator |
| | 527,213 | Oct. 09, 1894 | E.J. McClellan | Milling Machine |
 | 666,156 | Jan. 15, 1901 | E.B. Ridgway | Steam hydraulic elevator |
| | 1,884,277 | Oct. 25, 1932 | B. Sassen | Self Regulating Hydraulic System |
| | 2,006,312 | Jun. 25, 1935 | H. Ernst, B. Sassen | Compensating Bleeder Valve |
| | 2,027,706 | Jan. 14, 1936 | L.L. Schauer, J.H. McKewen | Counterbalance valve |
| | 2,216,800 | Oct. 08, 1940 | W.G. Baldenhofer | Hydraulic Control Device |
 | 2,353,246 | Jul. 11, 1944 | M.T. Knutzen | Control means for power-operated machine |
| | 2,464,626 | Mar. 15, 1949 | A.P. Waterson | Pilot Operated Servo Valve |
