How does a lotion pump work?

Lotion pump is a kind of liquid distributor that uses the principle of atmospheric balance and mechanical rebound mechanism. It can pump out the liquid in the bottle and replenish the outside atmosphere by pressing. The core lies in the coordination between the internal piston and the one-way valve, ensuring one-way flow of liquid and good sealing.

Work cycle mechanism

The working process of the lotion pump is mainly divided into two stages: press discharge and rebound absorption, forming a continuous cycle:

1. Press to discharge: When manually pressing down on the pump head, the piston moves downward to compress the spring, reducing the volume inside the pump chamber and increasing the pressure. At this point, the bottom one-way valve (such as a glass ball) is closed, the top valve is opened, and the liquid is sprayed outward through the nozzle chamber.

2. Rebound suction: After releasing the pump head, the spring returns and pushes the piston up, increasing the volume inside the pump chamber and creating negative pressure (sub vacuum state). Under negative pressure, the top valve closes and the bottom one-way valve opens. The liquid in the bottle is sucked into the pump chamber through the suction tube for storage, preparing for the next press.

3. First use: When pressed for the first time, the pump chamber is filled with air. It is necessary to press multiple times to evacuate the air and establish a vacuum before the liquid can be discharged normally.

Key structural components

The efficient operation of lotion pump depends on the combination and sealing design of multiple precision accessories:

-Core components: including nozzle, piston, spring, pump body, and suction tube, most of which are injection molded from plastic materials such as PE and PP.

-Control valve: Use glass beads or ball valves as one-way valves, with sealing gaskets to prevent liquid backflow or leakage.

-Sealing performance: A good sealing structure can effectively isolate air, reduce contact between the contents and the outside world, avoid oxidation pollution, and extend the service life of the product.