| 摘要 |
PURPOSE:To lighten the speed change shock by installing a sequence valve which answers to the pressure of a medium/high speed stage selecting pressure circuit and introduces the line pressure into the circuit from a high speed stage holding pressure circuit, when the pressure in the selecting circuit is at least set pressure, and opens a drain port to the atmosphere, when the pressure is below the set value. CONSTITUTION:In a circuit consisting of a 2-3 shift valve 20 as shift valve for speed change between low/high speed stage, a 3-4 shift valve 21, and a sequence valve 22, the delay DELTAT' in the discharge of the high-speed stage selecting pressure (4-speed selecting pressure C4) for the discharge of the medium/high speed stage selecting pressure is set by the sequence valve 22 corresponding to the medium/high speed stage selecting pressure, in the leaping-over down- shift speed change (4 2 speed change) from the high speed stage to the low speed stage. Therefore, the leaping-over speed change can be certainly achieved without passing through the medium speed stage, and speed change shock can be lightened. |
