Numerical investigation on roll forming of straight bevel gear

Gear is an important power transmission part, which has been widely used in aviation, aerospace, vehicles, instruments, mining machinery, and other industries. The gear teeth are formed with two methods of chip removal processing and precision plastic forming. The plastic forming method overcomes the defects of chip forming; the internal metal flow line is continuous, the material utilization ratio is high, and the production efficiency is high. In order to avoid the defects of rabbit ear in gear roll forming, the forming process of rolling bevel gear is studied in this paper. Studies have shown below. In the process of forming the bevel gear, the defects of the rabbit ears will be generated, and finally, the defects of the folding are formed in the forging. The defects of the rabbit ears must be eliminated during the forming process. When the friction shear factor is 0.1, 0.3, 0.5, 0.7, and 1.0, the maximum increment of rabbit ear is about 0.51 mm. The left profile first forms the top of the tooth, and the tooth top of the left tooth profile forms the left rabbit ear under the extrusion of the convex tool. The right-hand contour of the tooth blank is finally formed, and the rabbit ear of the right tooth profile is formed by the bending extrusion of the convex tool. In the multi-pass roll forming method, the occurrence of rabbit ear defects in roll forming process is effectively suppressed when the big end tooth height of bevel gear is 3.2 mm, 6.5 mm, 9.8 mm, and 13.1 mm and rolling wheel feed is 1.9 mm, 3.5 mm, 5.2 mm, and 6.9 mm, respectively.