Why can the constant pressure liquid storage bottle ensure the constant working pressure?

According to today's headline data, the principle that the constant pressure liquid storage bottle can ensure the constant working pressure is to use the principle of air pressure, water pressure and liquid level balance, to convert the pressure in the pipeline into the pressure in the air chamber by adjusting the height difference, and to control the water pressure in the pipeline by adjusting the pressure in the air chamber.

Tap water enters the constant pressure water supply tank, and the pressure will squeeze the air in the air chamber, which will increase the pressure in the air chamber. When the water pressure exceeds the set value, the regulating valve will open, so that part of the water will flow back to the tap water pipeline, thus keeping the water pressure constant. When the water pressure decreases, the regulating valve will be closed, tap water will enter the air chamber again, and the air chamber pressure will continue to increase, thus maintaining a constant water pressure.