Daily chemical pump head is a kind of packaging material, widely used in cosmetics packaging materials.When using the pump head, the material body will not be exposed, and the human body will not come into contact with the material body in the packaging container.According to the characteristics of the material body to choose different pump head can control the discharge and discharge effect, just press to discharge the material.Based on the advantages of hygiene, convenience and variety, pump head is widely used in cosmetic packaging materials.It is particularly important to control the quality of pump head.
This paper mainly discusses the detection method of the function items of the emulsion pump head besides the appearance and size items.First let’s look at the classification and principle of the pump head.
First, the classification of pump head
1.Pump head according to the head cap (pressure head) open way is different, can be divided into screw pump head, clamp pump head, about locking pump head, hand-held pump head (spray gun), direct pressure type cover pump head and about locking type cover pump head.The manual button pump head is mainly used for detergent products such as degreasing and glass cleaning.The above classification is Bian Xiao according to their own understanding of classification.
2.Pump head can be divided into emulsion pump head, foam pump head, vacuum pump head, spray pump head (nozzle), aerosol pump head.
Second, pump head principle
1.Principle of emulsion pump head
Emulsion pump head is a small reciprocating piston pump.Manually press the pressure head of the pump head, and the spring in the storage chamber is compressed.In the process of compressing the spring, the vent hole of the pump core is opened, and when the piston slides, the air in the pump core is discharged through the vent hole.Press back and forth to discharge the air in the pump core.
When the pressure head of the pump head is released, the spring bounces back due to pressure loss, closing the discharge port.At this time, the liquid storage chamber is in a vacuum suction state, glass (steel) beads are sucked up, and the material in the bottle is sucked into the liquid storage chamber through a straw.Press the pump head back and forth for many times to suck the material, and store the material in the pump core until all the materials are stored.Press the pump head again, and the material will be pumped out directly from the pump nozzle through the discharge port.
2.Principle of vacuum pump head
Vacuum pump head without suction.There is a small hole in the bottom of the bottle that matches the vacuum pump head.There is a piston in the bottle.Small holes are left in the bottom of the cylinder to allow the bottom of the piston to communicate with the atmosphere.When the vacuum pump head is pressed down, the air in the bottle chamber is expelled and the pressure is reduced.Because of the difference in internal and external pressure, the pistons in the bottle will move up, pushing up the material in the bottle.When the material is in contact with the suction inlet of the pump head, the material is extracted from the pump nozzle by pressing the pressure head back and forth.
3.Principle of foam pump head
The foam pump head is mainly used for hand sanitizer, facial cleanser, shampoo and shower gel, especially for children.The internal structure of foam pump head is complex.
After the material in the bottle passes through the mesh inside the foam pump head, the material is wrapped in the air and foamed by the tiny mesh, thus pressing the foam out.
4.Spray pump head (nozzle) principle
Spray pump head mainly uses Bernhard principle, fast fluid flow rate, small pressure, slow flow rate, high pressure.This is also the principle behind the so-called “banana kick” in soccer penalty kicks.
By press the nozzle, as a result of the bottle inside and outside differential pressure, the material within the bottle, high-speed flow of the material flow will drive the nozzle mouth nearby gas, increase the velocity of the gas near the nozzle mouth, the pressure is reduced, thus forming a topical negative pressure zone, the surrounding air mixed in the liquid, form a gas-liquid mixture and spread the material in the air, have atomization effect,Form small particles of suspended air.
5.How aerosol pumps work
An aerosol product in a package is packaged in a pressure container and contains the propellant.In general, the pressure in the aerosol tank is higher than the external atmospheric pressure.When the head is pressed down, the valve passage opens and the pressure in the aerosol tank causes the material in the tank to rise through the pipette and eject out of the nozzle.When the material passes through the narrow nozzle at high speed, droplets are formed due to the rapid evaporation of the propellant.Change valve configuration and spray foam.Like shaving foam.
Thirdly, Several factors affecting the pump efficiency of emulsion pump head?
1.The sealing performance of the glass (steel) bead under the spring: the sealing performance here is related to the upward scouring force of the liquid in the spring chamber.If the sealing performance is not good, when the pump pressure head, there will be some material leakage into the bottle, thus affecting the pumping effect.
2.the sealing performance of the upper sealing ring of the valve body: if there is a leak, when the pressure head of the pump head is released, the force of the material sucked into the spring chamber will be reduced.