Patent ID: 7950416

Claim:
A solenoid valve comprising: a sleeve which has an internal space that is formed with an input port, an output port and a drain port, a spool which is an axial member that is inserted in the internal space and which provides communications and cut-offs among the individual ports, due to axial movement of said spool, and a solenoid portion which axially moves said spool; wherein an input notch is formed in one of said sleeve and said spool so that a working oil flows into the input port through the notch, while a drain notch is formed in one of said sleeve and said spool so that the working oil is drained from the drain port through the notch; and the input notch and the drain notch are formed so as to satisfy 0.72≦Hin/(Hin+Hdr)<1.0 where Hin denotes an axial length of the input notch, and Hdr denotes an axial length of the drain notch.