【摘要】 基于双稳态机构精密定位特性,提出一种惯性力致动双稳态开关方案.该双稳态开关由四个初始形态为余弦形的悬臂梁及其支撑的质量块构成,质量块敏感阈值加速度后跳变到另一稳态,与触点接触实现开关导通.通过有限元法对比分析余弦形和圆弧形双梁机构在实现双稳态功能上的差异.采用湿法腐蚀钼片制作原理样品,其中余弦形双梁机构样品具有双稳态效应和闭合锁定功能.经离心测试,开关闭合阈值加速度为15gn,闭合电阻为2Ω;冲击实验表明在脉宽12ms幅度50gn的半正弦冲击下样品不会闭合;振动实验表明样品可通过三个方向各5min的量级为0.2g2n/Hz的振动测试而不破坏.更多还原

【Abstract】 A kind of bistable switch actuated by inertial force is proposed according to precisely positioning characteristic of bistable mechanism. The sensitive unit of the bistable switch consists of a seismic mass supported by four initially-shaped cantilever beams. The movable mass would snap through to the other stable state position, i.e, the electrode position, when it is subjected to threshold acceleration. The switch will thus turn on and keep contact. Comparison analysis is performed to verify the difference in achieving bistable effect between cosine and arc shaped double-beam mechanism. The prototype of the switch is fabricated with method of molybdenum wet-etching. Only cosine-shaped double-beam mechanism can achieve bistable effect and close-locking function. Centrifugal test shows that switch-on threshold acceleration is 15 g_n while the contact resistance is 2 Ω. Impact test shows the prototype won’t switch on under pulse width 12ms and amplitude 50 g_n half-sine impact. Vibration test shows that it can pass the test without destruction and fracture under 0.2 g~2_n/Hz three axial each 5 minutes’ random vibration.更多还原