The circular motion of the motor makes the diaphragm inside the pump reciprocate through mechanical devices, thus compressing and stretching the air in the pump cavity (fixed volume), and under the action of the one-way valve, a positive pressure is formed at the outlet (the actual output pressure is related to the resistance of the pump outlet and the characteristics of the pump); A vacuum is formed at the water pumping port, resulting in a pressure difference with the outside atmospheric pressure. Under the action of pressure difference, the water is pressed into the water inlet and then discharged from the water outlet.
Under the action of the kinetic energy transmitted by the motor, water is continuously sucked and discharged, forming a relatively stable flow.
The miniature diaphragm pump is generally driven by a low-voltage DC brush motor, and the circuit should be anti-parallel diode freewheeling. When there is no liquid in the pump, it is similar to the no-load of the motor (the winding current of the pump motor is relatively low), and the diaphragm is soft plastic, which has no large mechanical stress and can be dry-pumped.
In the case of a DC low-voltage power supply, use a miniature diaphragm pump.
This is the first one.