After the precision plastic work is completed, the workpiece may be close to the punch or stuck in the die, which needs to be removed or ejected. The device for removing the workpiece from the punch or mandrel is called the unloading device, and the device for ejecting the workpiece from the die is called the ejecting device. Demoulding of helical gear forging has always been a key problem in the research of precision plastic forming of helical gear. Due to the helical surface of the tooth surface of the helical gear, the formed helical gear forging cannot be demoulded according to the ordinary ejection method like the ordinary gear. It is necessary to design a set of reasonable dies to make the spiral gear forgings demould smoothly.
The key problem of difficult demoulding of spiral gear forgings after precision plastic forming is studied, and the centripetal bearing structure female die is designed. The tooth cavity can rotate freely along the axis of the helical gear. The ejector rod exerts an axial upward force on the forging, and the workpiece also exerts a tangential force on the concave die through the tooth spiral, so that the tooth cavity rotates along the spiral gear axis. The problem of synchronization between the axial upward movement of the forging and the rotation of the tooth cavity along the spiral gear axis is solved, and the forging is screwed out of the concave die.