Patent ID: 7513272

Claim:
A solenoid valve comprising: a solenoid portion comprising a stator core, an electromagnetic coil wound around said stator core, and a plunger axially moving in said stator core when said electromagnetic coil is energized; a valve portion comprising a valve sleeve, a spool forming plural lands and axially moving in said valve sleeve, and a spring biasing said spool; and wherein said solenoid portion and said valve portion are coaxially fixed in series such that said plunger and the spool are coaxially disposed in series with an intermediate space therebetween, whereby said spring biases said plunger via said spool, which spool can be moved by said plunger due to an energization of said electromagnetic coil, wherein the intermediate space is defined in part by facing portions of said plunger and one of the lands of said spool, and wherein said facing portions have equal diameters so that the volume in the intermediate space does not change during movement of the spool, wherein said valve portion comprises a supply port, a control port and a drain port, and further comprises a feedback space formed between two of the lands of said spool, which lands have different diameters, and wherein said feedback space is arranged to receive a pressure in the control port, wherein the one of the lands defining said intermediate space is separated from said feedback space by at least one additional land.