Electromagnetic solenoid device for oil pressure control

Claim 1

An electromagnetic solenoid device for oil pressure control, comprising: a valve body having oil flow paths; a spool movable in an oil filled bore of said valve body for selectively communicating said oil flow paths; a solenoid device fixed to said valve body, said solenoid device having a solenoid case within which are positioned a solenoid coil mounted on a coil bobbin, a movable iron core, a stationary iron core, a sealed end and another end communicating with said bore of said valve body, whereby oil from said bore communicates with oil surrounding said movable iron core, said movable iron core including rod means for pushing said spool; a screw rod threaded into said stationary iron core; at least one oil pressure releasing means extending through said iron core in the direction of movement of said iron core; a return spring interposed between said stationary iron core and said movable iron core; and O-rings respectively provided at positions between said coil bobbin and said stationary iron core, between said coil bobbin and said solenoid case and between said screw rod and said stationary iron core to prevent leakage of working oil from said space for receiving said movable iron core.