某型波段开关瞬动动作特性及失效机理

目的 研究某型波段开关瞬动动作特性及磨损失效机理。方法 通过建立瞬动机构物理模型，进行瞬动机构滑动件受力分析、转动力矩随旋转角度变化分析，研究瞬动开关瞬动动作特性，分析并探讨瞬动机构的磨损失效机理。结果 在波段开关的瞬动角度范围内，瞬动力矩随着转动角度θ的增加呈先增大、后减小的趋势。在瞬动初始状态，旋转力矩为最小值1.2 kg·cm；当瞬动处于中间位置（瞬动角度为16°）时，转动力矩为最大值1.5 kg·cm；随着转动角度θ继续增大，转动力矩不断减小，最终恢复至初始值，与实物瞬动复位功能相符。瞬动机构滑动件受基座的正压力N随转动角度θ的增加而增大。基座塑料受过大压力产生磨损，使转动（复位）力矩降低，滑动件无法复位，导致瞬动功能失效。结论 某型波段开关瞬动功能由滑动件钢球、基座长弧形斜坡、接触压力保证，弧面磨损致使钢球所受接触压力分量不足，导致瞬动功能失效，该失效机制为疲劳磨损失效。可通过改变基座材料、滑动件结构或材料以及改善瞬动机构工作条件来提高瞬动寿命和可靠性。

Instantaneous Action Characteristics and Failure Mechanism of a Certain Band Switch

The work aims to study the instantaneous action characteristics and wear failure mechanism of a military band switch. The force of the slider of the instantaneous component and the change of the rotation torque with the rotation angle were analyzed, the action characteristics of the instantaneous switch were studied, and the wear failure mechanism of the instantaneous component was analyzed and discussed by establishing a physical model of the instantaneous mechanism. In the range of the instantaneous angle of the band switch, the instantaneous moment increased first and then decreased with the increase of the rotation angle θ. In the initial state of transient, the minimum value of rotational torque was 1.2 kg.cm, and the maximum value was 1.5 kg.cm when the transient was in the middle position (the angle of transient was 16°). As θ continued to increase, the rotation torque decreased and finally recovered to the initial value, which was consistent with the instantaneous reset function of the object. The positive pressure N of the slider of the instantaneous mechanism increased with the increase of the rotation angle θ. The base plastic was worn by the excessive pressure, which led to the reduction of the rotation (reset) torque and the failure of the slider, which led to the failure of the transient function. In conclusion, the instantaneous function of a certain band switch is guaranteed by the sliding steel ball, the long arc slope of the base and the contact pressure. Wear of the cambered surface leads to the insufficient force component of the steel ball, which leads to the failure of the instantaneous function. And the failure mechanism is fatigue wear failure. The life and reliability of the certain band switch can be improved by changing the base material, the structure or material of the slider and improving the working conditions of the instantaneous component.