Hydraulisches Steuer- und Regelventil

摘要

1,065,346. Valves; hydraulic transmission. INTERNATIONAL HARVESTER CO. July 13, 1964 [July 17, 1963], No. 28828/64. Headings F2C, F2D and F2V. A valve controlling the flow of fluid from a pump to two motors comprises a housing having two identical rotatable spool valves, the spool 50, Fig. 2, being rotated by a lever 61 through gears 59, 65, while the second spool (not shown) is rotated by a lever 60 through gears 58, 64. Each valve spool has lands 122R, 123R, 124B, 125R forming grooves 126R, 127R, 128R, the grooves 127R, 128R being connected to motor ports 54, 56 and the groove 126R being connected to the inlet. The land 124R has diametrical opposite axial grooves such as 135R leading from groove 127R and grooves 136R, 137R leading from grooves 128R, the axial grooves being 90 degrees apart. Axial grooves 132R, 133R are arranged leading from groove 126R. When the spool is in the position shown no flow takes place to the motor but when the spool is rotated through 90 degrees in either direction the motor ports 54, 56 are connected to supply and exhaust or vice-versa. Each valve has three positions providing nine combinations of the positions of the valves. In the event of an excess pressure in one of the ports 54 or 56, the fluid acts in passage 140R or 145R in co-operation with piston members 142R or 147 to move the spool to the right or left to connect a groove 119R or 118R to the axial grooves on the lead 124R to allow circulation of fluid between the parts. Fig. 6 (not shown) provides the arrangement of passages for interconnecting the bores of the two spool valves. The inlet pressure also acts on an anticavitation valve which prevents flow of the exhust when the pressure falls. A relief valve, Fig. 3 (not shown), has a piston (105) which is moved against a spring (109) to open radial ports (101), (101a) and a flange (108) opens passages (102), (102a) when the pressure exceeds a predetermined value. The valves are used to control the supply from a variable displacement pump 10, Fig. 5, to motors 34, 35 connected through gear-boxes 38, 39 to axles of a vehicle. The supply line 13 is connected to the relief valve 19 and the line 24 to the anticavitation valve 22. The return flow passes to a tank 12 through a filter 16 having a by-pass valve 26. The pump 10 is driven from the engine 28 and is adjustable manually by a member 29.