Pilot operated variable force solenoid valve in an automatic transmission control circuit.

摘要

A throttle valve system for an automatic transmission control circuit comprising a variable force solenoid pilot valve (170-194) and a pressure regulating throttle pressure spool valve (196-212) 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 (234) 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.