When the air is pushed forward, the particle density in front of the fan will increase, the air pressure will increase accordingly, and the air density behind the fan will decrease. The pressure drop behind the air pump is just like the pressure drop in the straw when you suck a drink.
The pressure behind the air pump is lower than the pressure outside the vacuum cleaner, that is, the ambient air pressure. This will create a suction force inside the vacuum cleaner, that is, a partial vacuum. Therefore, the air outside the cleaner automatically enters the cleaner through the air inlet.
Extended data:
Working principle:
The working principle of air suction pump is the same as that of micro vacuum pump, which is the circular motion of motor. The diaphragm inside the pump moves back and forth through mechanical devices, thus compressing and stretching the air in the pump cavity with a fixed volume, forming a vacuum (negative pressure), which makes the suction port of the pump have a pressure difference with the external atmospheric pressure. Under the action of pressure difference, gas is forced (sucked) into the pump cavity and then discharged from the exhaust port.
It is precisely because the pressure difference between the air outlet and the outside atmosphere can be formed, and at the same time, unlike large vacuum pumps that need lubricating oil and vacuum pump oil, it will not pollute the working medium, and has the advantages of small volume, low noise, maintenance-free, and 24-hour continuous operation.
Therefore, micro vacuum pump, as a power device, is widely used in gas sampling, gas circulation, vacuum adsorption, accelerated filtration, automobile vacuum assistance and other occasions, and is widely used in medical, health, scientific research, environmental protection and other fields.
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