The Research Of Design Technology For Acceleration Switch With Cross Springs

The acceleration switch with cross springs is a kind of linear acceleration threshold value switch, which is fixed on aircraft. It measures the acceleration caused by outside force besides universal gravitation. For example, the acceleration is caused by the thrust or the air resistance. The switch turns on when the acceleration reaches to threshold value.The structure of the acceleration switch with cross springs differ from the structure of the switch used before, For small-bulk, simple-structure and convenient- assembly, it is a product which is suitable for miniaturization.According to conditions of the product, the force analyses of acceleration switch with cross springs are given. The failure forms of acceleration switch with cross springs is discussed. The design criterion of acceleration switch with cross springs is put forward. The calculation formulae of strength and stiffness for acceleration switch with cross springs are derived, and the methods of calculating the strength and stiffness are put forward The change laws of the strength and stiffness of acceleration switch with cross springs are studied The strength change curves and the stiffness change curves of acceleration switch with cross springs are obtained by changing its parameters. And the effects of the change of structural parameters and load on strength and stiffness of acceleration switch with cross springs are discussed.The theory of fuzzy reliability is used for the design of acceleration switch with cross springs. The approach of fuzzy reliability design for acceleration switch with cross springs is put forward for the first time. The randomness of working stress and the fuzziness of allowable stress are discussed. The corresponding formulae of calculating the fuzzyprobability are presented.For the first time, the fuzzy optimization theory is applied to study the principle and method of the two objective fuzzy reliability optimum design of acceleration switch with cross springs. The constraint conditions and design variables are presented. The mathematical model of the two objective fuzzy reliability optimum design of acceleration switch with cross springs is established. A method for finding the solutions of the model is given.With ANSYS software, the dynamic mode of the acceleration switch with cross springs is found and simulation analysis is performed to optimize design target as well as provide the final favorable design basis to the product.The problem of fault tree analysis for acceleration switch with cross springs is investigated The function block diagram of the acceleration switch system is given. For the first time, the fault tree of acceleration switch with cross springs is built up, and its structure function is presented. A calculating method of the reliability of acceleration switch system with cross springs is established and analyzedBy damping performance test we manage to solve the long-time problem of quantifying delay time when the acceleration switch actuates. Delay time of such type of product is obtained to provide the satisfying design basis to the system. And moreover, the sinusoidal vibration test method of the damping coefficient is more scientific and precise than the current method of inputting step value artificially. It can provide useful reference of the damping test to the same type of products.