Abstract: A variable capacity pump delivers fluid at full displacement until both the main high pressure system and the lube system are satisfied. The main system pressure is regulated by a valve connected to the pump discharge while the lube pressure is regulated by a valve disposed in fluid communication with the overflow of the main system valve. The lube system valve establishes fluid pressure for the lube system and directs excess fluid to the displacement control for the pump whereby pump displacement is decreased when both systems are satisfied.

Abstract: The control valving for a dual pump hydraulic system has two regulator valves which control the distribution of pressurized fluid, on a priority basis, to a high pressure system, a low pressure system and a lube system. One regulator valve controls flow from both pumps to the high and low pressure systems. The other regulator valve controls flow from one pump to the lube system and bypasses excess flow from the other pump to the system reservoir. The first regulator valve satisfies the high pressure system requirements before any fluid is directed to the low pressure system. The other regulator valve receives fluid downstream of the first regulator valve and satisfies the low pressure system before any fluid is directed to the lube system or to the fluid return passage to the reservoir.

Abstract: A hydraulic control for a power transmission has a regulator valve for controlling the hydraulic system pressure and a plurality of shift valves for controlling the automatic ratio change in the transmission. The shift valves are urged toward the higher ratio position by a governor pressure. The shift valves, except the 1-2 valve, are selectively subjected to separate modulated throttle valve pressures acting in opposition to the governor pressure and depending upon whether the respective shift valve is in the lower or higher ratio position. The modulated pressures are maintained at substantially zero for a portion of the throttle valve pressure range so that upshifting and downshifting will be sensitive to governor pressure and therefore vehicle speed only.The regulator valve is subject to a variable bias pressure which is proportional to throttle valve pressure.

Abstract: A hydrodynamic drive and slipping clutch arranged in parallel drive relation to provide a controlled slip input drive to a mechanical gear arrangement. The clutch slip is controlled by a passage having a variable opening responsive to the torque transmitted by the hydrodynamic drive to split the input torque so as to limit the torque transmission through the hydrodynamic drive. The clutch transmits the remainder of input torque from the prime mover to the gearing.