Actuator of regulator and fluid regulator

A fluid regulator, comprising:

• a valve body having an inlet, an outlet, and a fluid flow path extending between the inlet and the outlet;
• a valve element assembly comprising a valve rod, a valve port arranged in the fluid flow path, and a valve flap disposed in the fluid flow path and connected to the valve rod;
• and
• an actuator, comprising:
• a shell;
• a limiting component disposed on an inner wall of the shell;
• a diaphragm assembly disposed in the shell, the diaphragm assembly being movably sleeved on the valve rod, the diaphragm assembly comprising a diaphragm and an upper tray, the upper tray having a first portion that engages the diaphragm and a second portion that extends away from the first portion and toward the limiting component, the second portion of the upper tray arranged to selectively engage the limiting component to deter movement of the diaphragm assembly past a limit;
• and
• an elastic element disposed in the shell and outside of the valve body, the elastic element being coupled to the diaphragm assembly and being movably sleeved on the valve rod, between the diaphragm assembly and a tip of one end of the valve rod located within the shell, in a compressed state,
• wherein the limiting component is located above the diaphragm assembly and an inner diameter of a portion of the limiting component is smaller than an outer diameter of the upper tray of the diaphragm assembly,
• wherein the valve rod is movable to move the valve flap between a closed position, in which the valve flap engages the valve port, and an open position, in which the valve flap is spaced from the valve port, to control fluid flow through the fluid flow path.