| As a common brake, drum brake has obvious advantages. For example, the obvious braking effect, relatively simple structure and very compact mechanism. Besides these, the price is very affordable and easy to install, etc. So it is widely used among medium-sized trucks and some cars. However, the general drum brakes have following deficiencies, such as instability of brake thermal efficiency, braking efficiency is reduced after soaking, the braking torque is reduced in the same quality and size compared with disc brakes and so on.Brake shoes of bi-energizing drum brake not only get the urging force of the brake wheel cylinder during braking, but also get reverse force from connecting rod and the support pin. Bi-energizing drum brake has characteristics of friction momentum remarkably and bidirectional work.The studies about energizing type drum brake are less in China and the main study contents only involve single temperature field or structure field. In fact, the temperature field and the structure field together work and mutual coupling during braking, so the study of thermal-mechanical coupling analysis about bi-energizing drum brake has value of engineering application.The second chapter has determined the main dimensions of the drum brake by using automobile theory to conduct Bi-energizing drum brake’s mechanical analysis and matching the parameters of a model. The main dimensions are include brake drum’s radius, brake drum’s thickness, friction linings wrap angle,friction lining’s width, friction linings’s starting angle,friction linings’s thickness, friction linings’s area,the distance between the center of brake drum to the line of open force, the vertical distance between the center of the drum to the center of connecting rod and so on.The third chapter has accomplished digital modeling of the key components on drum brakes by using three-dimensional drawing software UG. The key components include brake drum, brake plate, friction linings, brake shoes, connecting rod and so on. After component design,The next is assembling the key components.The fourth chapter has accomplished brake’s structure and temperature field analysis alone and brake thermal-mechanical coupling analysis by workbench software module.Studies have shown the maximum stress and strain of analysis for brake shoes appearred the area of the edge line of a brake shoe inner panel in contact with brake shoe webs,the maximum strain of analysis for brake shoe binding linings appearred the area of the edge line of upper end of friction linings in contact with the brake shoe,Strain of friction linings is a.little great.so these places are the focus of intensive in the design and manufacturing process and need intensive or special treatment to further ensure the strength and stiffness of the brakes. The analysis of the brake drums and linings shows The maximum stress of brake drum does not exceed the allowable stress and the maximum stress and strain is within the engineering materials allowable range,so structure’s design meets the requirements.The comparison of the static structural analysis and thermal-mechanical coupling analysis for bi-energizing drum brake shows the rise of temperature has greater impact on the brake material strength and stiffness.The fifth chapter has designed test bench of brake torque and temperature on drum Brakes based on Multi-body dynamics and Stefan Boltzmann’s law and introduced briefly design thinking of sensor modules,signal processing module,data processing and display terminal modules and created a three-dimensional test bench and a partial exploded view of the key parts. The test bench designed has advantages of Simple structure, small disturbance by the data acquisition and high precision measurement compared with the traditional test bench. |
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