The forging technology of straight bevel gear is gradually mature, which provides a certain technical basis for the forging of spiral bevel gear and provides guidance for the selection of die materials. The difference between spiral bevel gear and straight bevel gear in basic parameters is only helix angle. The geometric changes caused by spiral bevel gear are mainly reflected in the aspect of gear teeth, and the tooth surface changes from the original plane to curved surface, This change has mainly brought the following problems:
1.Whether the blank fills the cavity completely during forging.
When forging the teeth of spur bevel gear, the die cavity is many V-shaped tooth grooves. This structure makes it easy for the blank to fill the bottom of the die cavity, and the yield is very high. However, in the tooth cavity of spiral bevel gear, the tooth grooves become curved V-shaped, and axial interference may occur when the pitch cone angle is small, In this case, the material is difficult to fill the bottom of the mold cavity, and the tooth profile will be defective.
2.Whether the die can be produced after forging.
After the forging of spur bevel gear, the forging can be ejected from the die by using the ejector rod on the die. This method has high efficiency and can carry out continuous production. However, the axial direction of spiral bevel gear may interfere, which makes it impossible to eject the die according to the ejection mode in some cases. It is necessary to consider a new ejection mode.
Through gear tooth modification and spiral die out, the filling rate of materials is improved, the die can be produced by forgings, and the forging feasibility of spiral bevel gears is improved. Wang Huajun and others have carried out forging experiments on driven spiral bevel gears with industrial pure lead as materials, and Chen Fuxiao and others have also carried out forging experiments. Gear forgings have been obtained through the development of dies and new materials, The forging of spiral bevel gear will eventually be applied to industrial production and contribute to the development of machinery industry.