Abstract: A hydrokinetic, multiple-ratio torque converter transmission mechanism having a simplified valve system with variable force solenoids for controlling line pressure as well as ratio shifts, a simplified clutch-and-brake hydraulic circuit with separate fluid pressure feed and exhaust passages, a common accumulator arrangement for controlling each of two ratio upshifts and a simplified brake servo mechanism having the dual function of establishing a torque reaction point for each of two distinct transmission ratios.

Abstract: A throttle valve system for an automatic transmission control circuit comprising a solenoid pilot valve and a pressure regulating throttle pressure spool valve for developing a throttle valve pressure for use in initiating control functions in a multiple ratio transmission wherein the output signal of the throttle valve can be used as an indicator of the driving torque wherein the force requirements of the variable force solenoid are reduced and wherein the sensitivity of the pressure regulating throttle valve to the output signal of the pilot valve and to changes in engine torque is improved relative to prior art throttle valve systems, the pilot valve being effective to control a larger flow insensitive regulating valve and the stroke of the solenoid actuator for the pilot valve being minimal.

Abstract: A multiple ratio automotive vehicle transmission having a hydrokinetic torque converter and a compound planetary gear unit that establish a plurality of underdrive ratios, a direct drive ratio and an overdrive ratio, the ratio changes from the first underdrive ratio to a second underdrive ratio from the second underdrive ratio to the direct drive ratio each being established by engagement by a single torque establishing device, brake means for controlling application and release of the torque establishing devices to effect transmission of reaction torque from a reaction element of the gearing to a stationary portion of the mechanism, said controlling means being adapted to establish optimum shift points during ratio changes regardless of the magnitude of the torque being delivered at the instant a ratio shift occurs.