Magnetic valve

A magnetic valve including a housing and an electromagnet having an armature housed in a chamber in said housing which is not infiltrated by a pressure medium to be controlled, a high-pressure chamber arranged to be connected with a source of relatively high pressure and an intermediate-pressure chamber located between said high-pressure chamber and said electromagnet, a wall having a passageway opening between said high-pressure chamber and said intermediate-pressure chamber, a low-pressure chamber subjected to relatively low pressure, said intermediate-pressure chamber communicating with said low-pressure chamber, a rod coupling connected to said armature of the electromagnet, a separate auxiliary rod positioned in said passageway opening in said wall between said rod coupling and said high-pressure chamber, a sealing apparatus for sealing the passageway opening in said wall containing said auxiliary rod from said high-pressure chamber, said passageway opening and said auxiliary rod being so dimensioned that only a small flow of pressure medium flows from said high-pressure chamber to said intermediate pressure chamber along the auxiliary rod whereby the pressure drop at said passageway opening between said high-pressure chamber and said intermediate-pressure chamber constitutes the greatest share of the pressure difference between high-pressure chamber and said low-pressure chamber, a membrane secured to said rod coupling and to said valve housing for sealing off the entry of said rod coupling from the electromagnet side into said intermediate-pressure chamber, said sealing apparatus including a closure part arranged to be actuated by said auxiliary rod whereby, in one position of said magnetic valve, said closure part is actuated by said auxiliary rod and permits a flow of pressure medium from the source of relatively high pressure to said intermediate pressure chamber.