Since the cycloidal gear meshing does not have the center-distance separability in the involute gear meshing transmission, the tooth profile curve equation is complicated, and the meshing of the ordinary cycloidal gear pump is multi-point contact. Therefore, the processing precision of the cycloid gear is high, and a small machining error may result in failure to assemble or uneven load. Prior to the 1980s, due to the limitations of design calculation methods and processing technology, the application of cycloidal gear pumps was limited. With the improvement of the processing technology level, especially the development of numerical control technology, the processing precision of the cycloidal gear is gradually improved, the cost is also lower, and the cycloidal pump is re-emphasized. Its application has also gradually expanded, from the general industrial field to the micro-machine hydraulic system and bio-engineering. With the advent of multi-toothed cycloidal gear pumps and the development of modern design and manufacturing technology, the research of cycloidal gear pumps has attracted the attention of scholars and manufacturers at home and abroad. Recently, many foreign companies have produced such gear pumps . It is understood that cycloidal gear pumps often appear on large quantities of air compressors, chillers, oxygen compressors, expanders and large batches of chemical raw material conveyors imported from abroad, especially in the chemical industry for conveying high viscosity liquids. . Some enterprises in China have begun to produce multi-toothed differential cycloidal pumps, but they all rely on imitation of similar foreign products, mainly to meet the needs of equipment maintenance.