Downshift valve in hydraulic transmission control system

摘要

In a hydraulic control system of an automatic power transmission for an automotive vehicle, a shift gear operable between a higher gear condition and a lower gear condition is designed to provide a satisfactory shift pattern to dictate the schedule for making an upshift from the gear ratios allocated to the shift valve and is arranged with a downshift which provides a satisfactory shift pattern to dictate the schedule for making a downshift between the particular gear ratios so that the respective shift patterns for the upshifting and downshifting schedules between the gear ratios can be selected independently of each other.