Pressure regulating structure of liquid tank

The utility model discloses a pressure regulating structure of a liquid tank and relates to the improvement of pressure regulating structures of liquid tanks. The pressure regulating structure of the liquid tank is simple in operation, small in size and stable in performance. The pressure regulating structure of the liquid tank comprises a cylinder body and is structurally characterized in that a first cylindrical cavity body is formed in the upper portion of the cylinder body, a second cavity body is formed in the lower portion of the cylinder body, the upper end of the first cylindrical cavity body is communicated with the outside world, a connecting port is formed in the middle portion of the lower end of the first cylindrical cavity body and is communicated with the second cavity body through an airflow channel, the airflow channel is communicated with a pipeline outlet of the liquid tank, a gravity valve body is arranged inside the first cylindrical cavity body, the connecting port is sealed by the lower