## 2 Design and Structure of Electromagnetic Pump  
### Electromagnetic Pump Description  
In the electromagnetic diaphragm pump system prototype, the design of the electrical system of the electromagnet coil and the selection and construction of the pump control system with the field calculations, and and the conducting of tests for the magnetic pump system, were carried out at the laboratory of Department of Mechatronics, Silesian University of Technology, Gliwice. The prototype pumps small amounts of liquid and startsthe so-called dry, i.e., exhaust fluid without first flooding the pump chamber. According to the design, the pump can generate a force that allows for the suction out of the liquid at the different height levels where the device is located. This height was estimated to be 0.5 m below the level of the location of the pump. Additionally, the structural elements of the housing was realized using 3D printing technology, including the development of software enabling the supervision of the device and its operation. The pump device creates a pressure difference between the inlet (suction side) and the outlet of the pump, allowing for the transport of liquid or sediment. The pump transfers the mechanical energy to a fluid (liquid or gas) by raising its pressure through a rotor, piston or membrane to compress it. The operation of a diaphragm pump involves two flexible membranes mounted on a shared shaft that repeatedly moves up and down to pump fluids. This movement creates a vacuum, which allows fluid to enter through the inlet of the pump. The membranes are in motion mechanically using the pistons (Figure 1a). Figure 1: (**a**) Cross-section of electromagnetic diaphragm pump with electromagnets containing the pump body; valve; diaphragm; spring; electromagnetic coil; iron core; magnetic isolation ring; and inner and outer armature. The operation of the diaphragm pump includes the compression air, marked in clear blue, the pressed material, marked in red, and the material sucked into the pump, marked in clear green. (**b**) Illustrative design concept of the selected pump model. The designed pump realized in the laboratory is constituted of a membrane, a permanent magnet, two electromagnets, two valves and the chamber. The cylinder pump chamber has dimensions of 65 \(\times\) 15 mm. The cylinder permanent magnet, N42, has dimensions of 25 \(\times\) 10 mm. The electromagnet 65 \(\times\) 30 core dimension is 30 \(\times\) 10 mm. The coil is wounded with a 0.3 mm length of wire and 2300 turns. The circular membrane has a diameter of 65 mm and a thickness of 1.5 mm. The mechanical force generated by the electromagnet is transferred through the magnetic field interacting with the permanent magnet located in the membrane structure (Figure 1b). The operation of the pump is based on changing of the polarity of the electromagnets. The interaction between a permanent magnet and the electromagnets causes the moving of the diaphragm. When the device is supplied (24 V), the current generated by the magnetic forces in the designed pump flows through the electromagnets. One of the electromagnets is positively polarized according to the direction of current flow, and the other one is negatively polarized. Then, the magnetic field generated by the electromagnets interacts with a permanent magnet embedded in the middle of the diaphragm. As a result, the diaphragm will move toward the direction of the electromagnets. The motion of the diaphragm creates a vacuum in the pump chamber. In Figure 1a, the operating cycle of the pump is distinguished:  
* Opening of the suction valve;
* Medium suction;
* Medium compression of air;
* Opening of the discharge valve;
* Compressed medium outlet. The inlet valve opens and liquid fills the pump chamber. The changing of the polarity in the electromagnets rapidly reverses the cycle. The outlet valve opens and the inlet valve closes so the water is forced out from the chamber.