The fluid whose pressure is to be controlled flows along pipe 1. A portion of the fluid flows along tube 3 and through flow-control valve 4 to the upper space of a membrane chamber. When the pressure of the fluid increases, membrane 5 is bent downward, shifting rod 6 and plunger 2. This changes the amount of delivery and, consequently, the pressure. The pressure of the fluid acting on membrane 5 is counterbalanced by weight 7, mounted on lever 8 which turns about fixed axis A. Weight 7 can be adjusted along lever 8. When the pressure drops, the elements of the regulator operate in the reverse direction.
$3894$LHP,Rg$