An air pump is a device which sucks in air from one side and discharges the air from the other side.
For example, a pump which generates air (bubbles) in a fish tank for goldfish, etc. is a type of air pump device.
Air pumps include a motor type, voice coil motor (electromagnetic) type, and piezoelectric type, etc. All the types use a valve to divide the suction and discharge, and generally repeat the suction and discharge of air through the reciprocating motion of a diaphragm by a drive source (motor / piezoelectric, etc.)
・Structure and features of a common motor type diaphragm pump
The diaphragm moves up and down by converting the rotation of a motor into the movement of the diaphragm. The volume of the pump housing in the center space repeatedly expands and contracts with this movement, and air is sucked in when it expands, and air is discharged when it contracts.
The valve provided for both the air outlet and discharge port creates air flow in one direction, and prevents the backflow of air.
The air flow rate and discharge (suction) pressure is determined by the rotational speed of the motor, and the movement amount of the diaphragm pump.
Generally, selecting the type of motor and size of diaphragm makes it easier to manufacture pumps with various air characteristics for motor type diaphragm pumps, which also makes it relatively easy to realize a high-pressure and high flow rate air pump.
However, since the motor is used as the drive source, the size becomes larger and the weight becomes heavier.
It is also accompanied by vibration and noise while operating, which tends to make the operating noise louder.
・Structure and features of common piezoelectric type diaphragm pump
The vibration of the piezoelectric element moves the diaphragm, and the air is sucked in and discharged by the fluctuating volume in the pump housing. Generally, since the vibration of the piezoelectric element is minute, large fluctuation of the diaphragm is not generated so easily, and the air flow rate tends to remain low.
To increase the output, a larger piezoelectric element and diaphragm is used, and as a result, the outer dimensions are also become larger.