Abstract:
A lot of heat will be produced inside an angular-contact ball bearing under high speed conditions, and high temperature rise will cause thermal deformation, leading to the changes of geometric position relationship of bearing internal channel curvature center and ball bearing center. Finally, the bearing dynamic state, in turn, will be affected. On the basis of the analysis of the bearing quasi-statics theory, the heat production caused by the bearing internal friction and the thermal deformation of bearing components were considered. Using thermal network, the spindle unit was divided into network nodes, and the node hot impedance was defined, thereafter, the steady state thermal network model was established. The thermal deformation of bearing components, caused by each node temperature rising under different working speeds and loads, was analyzed. The coupling relationship model between the bearing dynamic properties and thermal properties was established, and the bearing internal dynamic properties were analyzed. The results showed that considering the thermal deformation or not, the bearing contact load and contact angle with the change of bearing working speed and the load were significantly different. Under the condition of high speed, the bearing internal thermal deformation has a significant impact on bearing dynamic properties, becoming one of the main causes of bearing faults during normal use.
