煤质分析仪器用定量滑阀的轴向尺寸设计方法

Axial dimension design method of quantitative slide valve for coal quality analyzer

煤质分析类仪器需对具有代表性的样气或样液进行定量取样,滑阀广泛应用于色谱或光谱分析领域的流体介质方向控制,在阀杆和阀体相对滑动时阀杆的过流槽与阀体的过流孔之间形成新的连通关系,从而实现液路切换。从定量滑阀的功能分析、接口排布和密封设计两大方面介绍定量滑阀的接口拓扑功能,结合模型设计实例,阐述定量滑阀轴向尺寸关系的确定以及定量滑阀轴向尺寸综合的数学模型。分析由于连接关系的特殊性而导致阀体和阀杆的轴向尺寸设计难点,即特征间需满足严格的约束关系并保证良好的加工工艺性。根据定量滑阀阀体和阀杆相对运动前后两者特征间的覆盖关系,通过气孔的拓扑分析以建立气孔排布图,同时根据相应的尺寸约束关系而得到满足连通关系的轴向尺寸约束不等式组,在以加工工艺性最优的目标下转化成Matlab标准的线性规划模型并求解,得到最优的轴向尺寸设计方法。分析定量滑阀的设计实例可知,应用Matlab标准的线性规划模型,可验证气缸行程与气道容差的关系,从而得到较优的轴向基本设计尺寸。

Coal analysis instruments need to quantitatively sample representative gas or liquid samples.Slide valves are widely used in the field of fluid medium direction control in chromatography or spectral analysis.When the valve stem and the valve body slide are relative to each other,a new connection relationship is formed between the flow groove of the valve stem and the flow hole of the valve body,so as to realize the liquid circuit switching.Thispaper introduced the interface topology function of quantitative spool valve from two aspects of function analysis:interface arrangement and seal design.This paper expounded the determination of axial dimension relationship of quantitative spool valve and the mathematical model of axial dimension synthesis of quantitative spool valve combined with model design examples.Due to the particularity of the connection relationship,it is difficult to design the axial dimensions of the valve body and valve stem.The features must meet strict constraints and ensure good processability.According to the covering relationship between the characteristics of the quantitative slide valve body and the valve stem before and after the relative movement,the layout diagram was established through the topological analysis of the pores.Meanwhile,according to the corresponding dimensional constraints,the axial constraint inequality groups satisfying the connectivity relationship were obtained.By means of optimal processing technology,the Matlab linear programming model was obtained and solved to get the optimal axial size design method.Finally,with analyzing the design example of the quantitative slide valve,it can be seen that the Matlab linear programming model can be used to verify the relationship between the cylinder stroke and the port,so as to obtain a better axial basic design size.