A pressure regulator installs thick regulating handle on the transmission, thin tuning knob and output interface, transmission gear mechanism installed inside the transmission box, end covers installed at both sides of the transmission box, turbines inside the transmission box installed by bearings, axle sleeves with tuning rod inside the turbine, with one end of the tuning rod connected with the gas heave by the output interface, the other end of the tuning rod connected to the thick regulating handle, worm fitting with the turbine inside the transmission box, with the worm installed inside the transmission box, the other end installed with thin tuning knob. The volume type pressure making design has long stable output pressure, and reduces the signal wave due to pressure inertia.