Servo valve

A servo valve comprising a valve housing, a valve spindle movable axially within said housing, a drive for operating said spindle, and a position controller for actuating said drive depending on the position of said spindle, wherein said valve spindle is operatively coupled to said drive by a lever and a link body;

• said lever is pivotally mounted in a lever housing interposed between said valve housing and said drive with one end of said lever housing connected to said valve housing and another end of said lever housing connected to a housing for said drive and said position controller is disposed on said lever housing;
• wherein said lever is arranged in an enclosed lever chamber in said lever housing;
• wherein said lever housing comprises a spindle chamber into which a part of said valve spindle extends, said spindle chamber being divided from said lever chamber by a dividing wall;
• wherein a guide block coupled to said spindle and to said lever extends through said dividing wall, said guide block being movable in the direction of the axis of said spindle;
• and
• wherein said guide block is provided with a centering cone which lies adjacent a slotted cone nut, and said slotted cone nut is threaded onto an external thread of said spindle and clamped to said centering cone concentrically therewith by a coupling.

A servo valve comprising a valve housing, a valve spindle movable axially within said housing, a drive for operating said spindle, and a position controller for actuating said drive depending on the position of said spindle, wherein said valve spindle is operatively coupled to said drive by a lever and a link body;

• said lever is pivotally mounted in a lever housing interposed between said valve housing and said drive with one end of said lever housing connected to said valve housing and another end of said lever housing connected to a housing for said drive, and said position controller is disposed on said lever housing;
• wherein said drive comprises a pneumatic diaphragm arranged in a diaphragm housing, said diaphragm housing comprising lower and upper housing parts clamped together by a clamping band;
• wherein said diaphragm comprises a flexible annular ring having an outer margin secured to said diaphragm housing and an inner margin secured to a centrally disposed diaphragm spring plate;
• and
• wherein said inner margin of said annular ring is received in an annular groove in said diaphragm spring plate, and at least one reinforcing wire is provided in said inner margin to render said inner margin resistant to stretching.