| 摘要 |
PROBLEM TO BE SOLVED: To avoid the occurrence of a malfunction that there arises a state that an input port communicates with neither a first output port nor a second output port without increasing the number of part items, in a spool valve embedded in a hydraulic circuit which discharges the working oil of an engagement oil chamber of a hydraulic engagement element of a transmission.SOLUTION: When an input port 57 is usually located in a position in which the input port communicates with neither a first output port 58 nor a second output port 59 by a land 64 and a land 66 of a spool 60, a notch 64a is formed so as to make the input port 57 and the first output port 58 communicate with the land 64. By this constitution, a malfunction which occurs in a state that the input port 57 communicates with neither the first output port 58 nor the second output port 59, for example, a malfunction that remaining pressure acts on an engagement oil chamber of a brake B3 due to the leak-in of oil pressure from a hydraulic circuit can be avoided. |
