The deformation of CNC gear hobbing machines after being heated is an important reason that affects machining accuracy, but CNC gear hobbing machines are in an environment where temperature changes anytime and anywhere; The CNC gear hobbing machine itself will inevitably consume energy when working, and a considerable part of this energy will be converted into heat in various ways, causing physical changes in various components of the CNC gear hobbing machine, which will vary greatly due to different structural forms, material differences and other reasons. The designer of the CNC gear hobbing machine should master the formation mechanism of heat and the temperature distribution law, and take corresponding measures to minimize the impact of thermal deformation on the processing accuracy. For example, Process 70mm on a regular precision CNC milling machine × Compared with the workpiece processed from 2:00 to 3:30 in the afternoon, the cumulative error of a 1650mm screw can vary by up to 85m. However, under constant temperature conditions, the error can be reduced to 40m

There are four measures to reduce thermal deformation of CNC gear hobbing machine spindles:

1. Reduce heat sources, with a focus on adjusting the rotational speed, clearance, and reasonable preloading of the spindle bearings. For thrust bearings and tapered roller bearings, due to their poor working conditions, they generate significant heat. If necessary, thrust angular contact ball bearings can be used instead to minimize friction and heat generation of certain components

2. Heat insulation to keep the heat source away from the main shaft, such as isolating the electric motor and gearbox, using separate transmission, etc

3. Heat dissipation, strengthening lubrication cooling, using oil cooling, air cooling, and other methods to accelerate heat dissipation

4. Reducing the impact of thermal deformation, regardless of the method used, can only reduce thermal deformation and is difficult to completely eliminate it. Therefore, measures should also be taken to reduce the impact of thermal deformation

If it is a sliding bearing, the wear resistance of the journal has a significant impact on the accuracy retention. Based on the basic requirements of the above working performance, it can be seen that the good rotational accuracy of the spindle component indicates good working accuracy and stiffness under no load conditions, good static working accuracy, good vibration resistance, and thermal deformation, indicating good dynamic characteristics of the spindle. Wear resistance determines its ability to maintain working accuracy