The use of cosmetic plastic pump heads should not be to […]
The use of cosmetic plastic pump heads should not be too frequent, because the resilience of the spring is limited. Each use must be within the range of the spring’s elasticity. It cannot be used strongly. This is the same as the limitation of a person. When a person’s physical strength is overdrawn, Collapsed. On average, the pump head should not be pressed more than 10 times each time, and the interval should not be less than 10 seconds. There must be enough time for it to rebound. The built-in spring of the cosmetic pump head should not be too long. Of course, too short is not acceptable. The selection and determination of the general wire diameter also plays a key role. Generally speaking, the spring of the ordinary cosmetic pump head is 13 and a half turns. Reasonable, so the resilience and pressing force are just within a reasonable range.
The principle of the lotion pump is to use atmospheric pressure
When using it, we first press to discharge the air in the reservoir (that is, the plastic tube that can absorb the shampoo). When the air is exhausted, press the pump head again. After letting go, the spring in the pump head To restore the original state, a vacuum will be formed in the liquid storage chamber, and negative pressure will be generated. At this time, the pressure in the container is consistent with the atmospheric pressure. Then, the pressure in the liquid storage chamber is low and the pressure in the container is high. , Due to the pressure difference, the atmosphere will press the liquid around the mouth of the liquid storage cavity into the liquid storage cavity, giving people the feeling that the pump head sucks up the liquid.
Why does the lotion pump fail to rebound after pressing the head
In order to avoid this kind of situation, in the production process, we should first check whether the length of the spring is standard. The difference is a thousand miles away. The effect of the length on the piston cannot be ignored. If it is short, the return stroke of the piston will not be in place. Directly cause the rebound after pressing the head down.
Secondly, check whether the thickness of the piston fits the body. During the movement of the piston, any gaps will cause the suction force to be weak and the body cannot be discharged by pressing the head. Due to the thermal expansion and contraction of plastics, a normal piston is very important to ensure the quality of the emulsion pump.
Finally, let's analyze the body. In view of the plastic's scalability characteristics, if the injection is not performed properly during injection molding, insufficient injection will cut off a thin layer of the body, resulting in uneven inner wall, and inevitably leaving the piston in the process of stamping. The gap makes it impossible to discharge the material.