蝶形激光器管脚振动疲劳寿命分析

针对用引线连接的蝶形激光器管脚在扫频振动测试中发生齐根断裂的问题,文章建立了有限元分析模型,模型中用不同管脚长度反映引线的影响,采用模态叠加法分析了管脚在20 g、20~2000 Hz正弦扫频振动下的应力。基于Miner准则,计算了管脚在振动条件下的寿命。分析结果表明:(1)原激光器管脚的固有频率高于2000 Hz,连接引线后,固有频率降低到2000 Hz以内,在振动条件下会发生共振;适当位置固定引线,可将其固有频率提高到2000 Hz以上,从而避免共振;(2)原激光器管脚在振动条件下为无限寿命,用引线连接后的激光器管脚寿命大幅降低,在适当位置固定引线可以将管脚寿命提高到无限寿命。

Fatigue Life Analysis of Butterfly Laser Pin under Vibration

In order to solve the problem that the pin of butterfly laser connected with lead wire breaks in the sweep frequency vibration test,the finite element analysis model is established with different pin length to reflect the influence of lead wire.The stress of the pin is analyzed by mode superposition method under the condition of 20 g and 20~2000 Hz sinusoidal sweep frequency vibration.Based on Miner criterion,the life of pin under vibration is calculated.The analysis results show that the natural frequency of the original laser pin is higher than 2000 Hz.After connecting to the lead wire,the natural frequency will be reduced to less than 2000 Hz,and the resonance will occur under the vibration condition.It is also shown that if the lead wire is fixed appropriately,the natural frequency can be increased to more than 2000 Hz to avoid resonance.Moreover,the results indicate that the original laser pin has infinite life under vibration condition,but the life of the pin connected by lead wire is greatly reduced.The pin life can be increased to infinite life by fixing the lead wire appropriately.