某埋头弹机枪拨弹杠杆动力学分析及优化

Dynamic analysis and optimization of the belt feed arm of a cased telescoped ammunition machine gun

某埋头弹机枪使用了与传统枪弹结构完全不同的埋头弹,为了适应这种弹药,该埋头弹机枪与传统机枪在结构上也有很大的差异。其中,相较于传统机枪,该埋头弹机枪的输弹行程更为靠后,为了减小全枪长度,不得不缩短拨弹杠杆中曲线槽部分的长度。这使得枪机框上的导柱进入拨弹杠杆曲线槽时,对拨弹杠杆的冲击力很大,从而对整个输弹机构的可靠工作造成极为不利的影响,同时也会严重降低枪机框的动能,使得输弹动作难以完成。现以导柱与拨弹杠杆之间的最大冲击力为目标函数,选用5次函数曲线作为拨弹杠杆曲线槽理论轮廓线的形状,运用遗传算法对该理论轮廓线进行优化,使得导柱与拨弹杠杆之间的最大冲击力降为优化前的1/3。试验验证表明,枪机框在进入拨弹杠杆曲线槽的过程中,速度损失由原来的0.94 m/s降低到0.28 m/s,达到了优化目的,该研究结果为该枪的改进提供了可靠的理论依据。

A cased telescoped ammunition machine gun uses a cased telescoped ammunition which is completely different from the traditional one.In order to adapt to this kind of ammunition,the structure of the cased telescoped ammunition machine gun is also very different from the traditional machine gun.Compared with the traditional machine gun,the cartridge feeding travel of the cased telescoped ammunition machine gun is at the rear part.In order to reduce the length of the whole gun,the length of the curve groove in the belt feed arm has to be shortened.This makes the impact force of the guide pillar of the bolt carrier on the ammunition transfer lever very large when the guide pillar enters the curve groove of the belt feed arm.This impact will have a very adverse impact on the reliable operation of the entire feed transfer mechanism,and will also seriously decrease the kinetic energy of the bolt carrier,making it difficult to complete the ammunition ramming action.The maximum impact force between the guide pillar and the belt feed lever was taken as the objective function,and the quintic function was selected as the the theoretical contour curve of the belt feed lever curve groove.The genetic algorithm was used to optimize the theoretical contour,so that the maximum impact force between the guide pillar and the belt feed lever is reduced to 1/3 of that before optimization.The test verification shows that the speed loss of the bolt carrier is reduced from 0.94 m/s to 0.28 m/s when the guide column enters the curve groove of the belt feed arm,and the optimization purpose is achieved.The results in this paper provide a reliable theoretical basis for improvement of guns.