The cost of magnets is low, the structure is simple, strong and sturdy. In some applications, in order to better improve its power characteristics, it is expected to choose magnets with constant force (or quasi-constant force characteristics. In order to better plan the production and manufacture of such magnets, it is necessary to Solve two basic problems: what structural plan should be selected; what preconditions should the key specifications satisfy. For the above two problems, two types of cylindrical DC electromagnet structures, a basin-shaped surface and a conical surface structure, are clearly proposed. The equivalent magnetic circuit method is followed by the analysis of most of the total permeance of the magnetic circuit, and the analysis and negotiation among the key specifications of the magnet when it is derived to generate constant force characteristics, and the inductive harm of each key main parameter to the force characteristics is analyzed. The point of analysis can be as follows: Further numerical calculation methods for magnetic fields are provided for proper calculation and experimental scientific research to open the entire selection program.



The analysis and calculation results are compared with the results calculated by the ANSOFT finite element analysis magnetic field mobile phone software, and it is confirmed that the method and point of view clearly put forward are appropriate. . Magnets are common push or execution components in industrial chain machinery and equipment integration machinery and equipment. When the current is a parameter, some magnets have the characteristics of force changing with offset within the range of their stroke arrangement (some are a few mm). Px) is a graph, the magnetic field force in the starting and ending directions is very far apart, and the vibration analysis and impact noise generated by this kind of force characteristics are very large, and the direction is not controlled arbitrarily. For some particular applications, such as actuators for market share relays, a flat force-offset characteristic is expected, ideally a constant force characteristic, oblique line.

Electromagnetic devices that produce constant force driving characteristics mostly use rare earth permanent magnet type moving coil structure, which is better than magnets, and can perform dual-theme activities, but the structure is chaotic and the price is high, especially in the case of small offset and large driving force. Not on the magnet sturdiness and economic development. The magnetic circuit analysis method and the magnetic field scale value analysis method are two common methods of magnet design. The former is easy to use, but not appropriate; the latter is calculated properly, but all the design specifications and material properties must be known at that time. Some are likely to use magnetic circuit analysis to obtain basic specifications, and then use magnetic field finite element software for actuaries and adjustments. In order to better plan magnets for flat force characteristics, 2 difficult problems must be solved:

①What structure plan to choose
②Key specifications should be satisfactory