制动钳及其约束对制动器热机耦合特性的影响

在定义零件间的约束关系和边界条件并且设置制动器摩擦系数、对流传热系数和橡胶衬套刚度等关键参数的基础上,建立了包含制动盘、摩擦衬片、制动块背板、活塞、制动钳、保持架、导向销及其橡胶衬套等零件的完整制动器热机耦合有限元模型.利用该模型对单次制动工况下的制动盘温度、周向应力和变形等热机耦合特性进行了分析.基于该模型将导向销橡胶衬套等效为弹簧单元和固定约束,发现橡胶衬套可忽略其几何结构等效为弹簧单元,但不可忽略为固定约束.最后,结合在制动器惯量试验台上开展的制动器热机耦合试验中热成像仪等设备测量盘面温度和变形的结果,验证模型的有效性,说明制动钳对制动器热机耦合特性有重要影响.

Effect of Brake Caliper and Its Restraint on Thermo-Mechanical Coupling Characteristics of Disc Brake

Based on defining the constraint and boundary conditions between parts and setting the key parameters such as brake friction coefficient, convection heat transfer coefficient and rubber bushing stiffness, a complete transient thermo mechanical coupled finite element model considering brake disc, friction linings, back plates, piston, brake caliper, bracket, guide pins and rubber bushings, was established. By using this model, the thermo mechanical coupled characteristics, such as temperature, circumferential stress and deformation, under single braking condition of disc were analyzed. In further research, it is found that the function of pin rubber bushings is equivalent to springs but can not be ignored as fixed restraint. The model was verified by thermo mechanical coupling test on brake inertia test bench. The results of thermal imager and other equipment show that the brake caliper has an important influence on the thermo mechanical coupled characteristics of the brake.