Research trends of spiral bevel gears

The advanced manufacturing technology and machine tools of spiral bevel gears have always been the guarantee for enterprises to maintain their core competitiveness. The earliest spiral bevel gear CAE software system was developed by Gleason company of the United States and used in conjunction with CNC control devices. It can realize the functions of gears from design to analysis, from processing to detection. The accuracy of gear pairs processed by this system can reach a very ideal level, which is a qualitative leap compared with the past; Numerical control technology and measurement technology are effectively combined, which greatly simplifies the structure of the machine tool, improves the rigidity of the machine tool, improves the sensitivity of mechanical drive, ensures the accuracy of gear machining, and greatly improves the machining efficiency; This process is of revolutionary significance to the production of spiral bevel gears, making the gear processing separate from grinding and enter a new stage. In recent years, Gleason has introduced universal motion principle (UMC) and critical motion graph (UMG), which overcomes the previous defect that high-order motion errors must be eliminated by gear lapping. The processing time of single pair of gears is reduced, and the economic benefit is significantly improved.

Spiral bevel gear processing machine tools have also experienced the development of general-purpose machine tools. The typical representative of the traditional mechanical gear milling machine is the no.116/118 hobbing machine milling machine of Gleason company in the United States, as shown in Figure 1. As a mechanical machine tool, the cost is low, but the calculation of machining parameters and the adjustment process of machine tool trial cutting and machining parameters are still very complex, the design and production cycle is long, and the machining accuracy is difficult to improve. China once imported a large number of such machine tools from other countries, but at present, such machine tools are still widely used in the actual production of current enterprises in China.

In the mid-1980s, the typical representative of CNC spiral bevel gear processing machine tools was Phoenix I and II CNC gear milling and grinding machines of Gleason company using free form technology. As shown in Figure 2, these machine tools have been fully CNC five axis machine tools. The rigidity and accuracy of the machine tools have been greatly improved. Compared with mechanical machine tools, the machining accuracy can be easily improved by more than one level. Gleason applied the self-developed bevel gear manufacturing expert system (GEMS) to this kind of machine tools, and the processed gears basically realized the unmatched installation of gear pairs.