| Automatic slack adjuster can automatically sense and timely compensate wear volume of the brake pad, which is the key component of automotive brake system. Frequent braking makes automatic slack adjuster constantly subject to the action of braking force, which will directly lead to the automatic slack adjuster’s fatigue failure. Studying the fatigue life of automatic slack adjuster helps to find the easiest prone to the position of fatigue failure, then we improve the structure of automatic slack adjuster, which can predict and avoid the case of brake failure happening timely, moreover, ensure traffic safety. The existing detection methods of fatigue life depend on the real vehicle tests entirely, which is time-consuming and labor-intensive, and greatly reduces the production efficiency. In view of these reasons, we put forward a life detection technology of automatic slack adjuster based on the model of finite element fatigue life, and the main contents include the following four parts:Firstly,we study the structural characteristics and working principle of automatic slack adjuster, and find three key structural units of automatic slack adjuster. With the help of the detection, the work load of the key structural units can be obtained. What’s more, we use the finite element analysis software ANSYS Workbench to do mechanical analysis of the key structural units.Secondly, according to the theory of fatigue analysis and the working characteristics of automatic slack adjuster, we determine the life theory analysis method of fatigue life of automatic slack adjuster. In addition, we use Fatigue Tool fatigue analysis module of ANSYS Workbench software for the model of finite element fatigue life. We use the model for the fatigue life analysis of automatic slack adjuster.Thirdly, according to relevant standard CJ_T 242-2007, we design a fatigue life detection device of automatic slack adjuster, which is controlled by Lab VIEW software platform. Meanwhile, it completes the test and the data management of the device to achieve function of human-computer interaction.Fourthly, fatigue tests of automatic slack adjusters are carried out on the fatigue test bench, and we come to a conclusion that the experimental result is 190,100 times,which meets the result of 204,030 times based on the finite element analysis usingANSYS Workbench FEA system, and verifies the accuracy of finite element fatigue life model. For the easiest prone to the position of fatigue failure, we improve the structure of automatic slack adjuster to meet the standards of fatigue life.According to the JBT 10633-2006 standard, we evaluate the accuracy of the test system. The results show that: measurement capability index test system(Cgã€Cgk)are both more than 2, %Gaga R&R and %P/T are both less than 10%,which meet the accuracy requirements of test system. In addition, the fatigue life detection technology based on finite element fatigue life model has been successfully used in Hangzhou Wolei tech. Co., LTD., and it has a significant engineering application value. |
