Gear transmission is the most widely used transmission mechanism. As the key component of the transmission device, gear has a history of more than 2400 years. Its main function is to transmit power and change the speed. Gear transmission has been widely used in various fields of modern industry, ranging from aviation, aerospace, shipbuilding, energy, transportation, weapons and equipment, to clocks and watches, micro electromechanical, medical equipment, micro robots and other fields. It has played an important role in the process of industrial development. With the development of modern industrial technology, higher and higher requirements are put forward for transmission gears, which not only meet the operating conditions of high speed and heavy load, but also meet the performance indicators such as high power density, low vibration noise and high transmission efficiency. In order to meet the above requirements, domestic and foreign scholars have carried out a lot of research in the research and development of gear tooth profile, and have achieved fruitful research results. From the aspect of gear tooth profile, gear types can be divided into involute gear, cycloid gear, parabola gear, curve gear, Logix gear, circular arc gear and studied point-line meshing gear. From the aspect of contact state, it can be divided into line contact meshing gear, point contact meshing gear and point-line contact meshing gear. Among them, involute gear, cycloid gear, parabola gear, curve gear and Logix gear belong to line contact meshing gear, Circular arc gear belongs to point contact meshing gear, while point line meshing gear belongs to point line contact meshing gear.
In practical application, involute gear is widely used because of its advantages such as high machining accuracy, separable center distance, accurate transmission ratio, good interchangeability, and insensitive to manufacturing and assembly errors, which makes it occupy a leading position in industrial production, with its market share reaching more than 90%. However, involute gear also has certain disadvantages, for example, the external involute gear belongs to convex-convex contact transmission, As a result, its bearing capacity is relatively low compared with the contact between concave and concave tooth surfaces, and the involute gear is also limited by the minimum number of teeth to be machined, resulting in the limited volume of its transmission device and the reduced power density, which can not fully meet the requirements of high-speed, heavy-load and lightweight. Cycloid gear, parabolic gear, curve gear, Logix gear and circular arc gear can only partially replace involute gear due to their own limitations (poor interchangeability, no separability of center distance, sensitivity to machining and assembly errors, manufacturing and testing difficulties, etc.), and have not been fully promoted. Based on this, domestic scholars have developed and researched point-line meshing gear.
Through consulting a large number of relevant documents, the senior engineer team of ZHY Casting systematically analyzed the current research status of point-line meshing gears, focusing on the geometric parameter design, strength check, tooth shape optimization, test verification, engineering application and other aspects of the point-line meshing gears, conducted in-depth analysis of the deficiencies in the current point-line meshing gear design system, and put forward some suggestions for the future research direction of this type of transmission, It is hoped that these suggestions can provide some help to improve the design system of point-line meshing gears.