Research On The Design And Key Technologies Of Micro Inertial Power Switc

According to the requirements of power supply control and safety of fuze power system and the miniaturization and dexterity of fuze parts,a kind of micro inertial power switch applied to medium and large caliber non-rotating projectile fuze power system is designed.Its response threshold,load identification characteristics and chip packaging and other key technologies are studied in detail.Combined with the working environment of the micro inertial power switch,the performance index requirements of the switch are put forward.Based on the working principle of the switch,the switch physical model composed of the environment response module and the power connection module is established.The switch displacement response,threshold characteristics and damping characteristics are analyzed theoretically,which provides guidance for switch design.The load identification mechanism of the switch is analyzed from the point of view of the difference of energy gain and loss,and a universal tooth load identification mechanism which can identify two typical environmental loads is designed based on the energy method.Then,the structure design of single threshold switch and multi-threshold integrated switch is completed,and their performance is simulated and analyzed.The results show that the two switches respond reliably to the design threshold and have the ability to identify the normal launch environment load and the service drop environment load.Finally,the prototype of independent threshold switch is developed by UV-LIGA process.In order to meet the requirements of switch miniaturization,two kinds of switch packaging schemes,FR-4 glass fiber PCB substrate COB package and CLCC preformed shell package,are designed..Compared with the original package scheme,the plane size is reduced by 67.4%and 62.5%,and the volume is reduced by 52.3% and 81.7%,respectively.Based on the numerical simulation method,the package thermal stress,which is the key factor affecting the package reliability,is analyzed and studied.In view of the excessive thermal stress in the switch package,a solution of "transition layer" is proposed and verified by simulation.The results show that the "transition layer" can reduce the thermal stress of the switch package and improve the package reliability.The encapsulated micro-inertial switch is tested experimentally,and the load identification and high impact resistance of the switch are studied.The experimental results show that all switches are disconnected under the simulated service drop load of Mushet hammer with amplitude of about 15100 g and pulse width of 47.55 μ s,and the threshold of 3000 g switch can be closed under the static acceleration load of 3111.78 g high-speed centrifuge(according to the empirical formula,the corresponding dynamic threshold is about 2222.7g,pulse width 2ms),and has the ability of load identification.The high impact resistance of the switch is tested by Mushet hammer.The structure of the two switches is intact under the high impact load with amplitude of 26900 g and pulse width of 64.21 μ s,and has high impact resistance and meets the design requirements.