Basic structure of a vacuum bottle

Vacuum bottles typically consist of a bottle body, cap, pump head (or valve), and possibly an internal piston or diaphragm. The bottle body is the container for storing the product, while the cap seals the opening to prevent outside air from entering. The pump head or valve is the key component controlling the product flow, and the internal piston or diaphragm separates the product from the air.

Initial State: Before use, the vacuum bottle is filled with product and a certain amount of air. At this point, the pressure inside the bottle is equal to the external atmospheric pressure.

Usage: When the user extrudes the product through the pump head or valve, the internal piston or diaphragm moves, gradually occupying the space previously occupied by the product. Due to the movement of the piston or diaphragm, the air inside the bottle is compressed, and the pressure gradually increases. Importantly, as the product flows out, a relatively low-pressure or vacuum area is created at the top of the bottle.

Vacuum Maintenance: To maintain this vacuum environment, vacuum bottles are typically designed with a one-way valve or sealing mechanism. When the user stops extruding product, the one-way valve closes, preventing outside air from re-entering the bottle. This maintains a relatively low pressure inside the bottle, which helps extend the product's shelf life.