渐开线齿轮副的最小侧隙计算与分析

齿轮副必须具备足够量的最小侧隙才能保证正常啮合传动。目前关于最小侧隙的计算还没有比较理想的方法,在理论上和考虑诸影响因素上也尚有争论,尤其渐开线圆柱齿轮精度制(JB179—83)简介中规定了最小侧隙的计算公式,我认为也同样存在着值得商榷的地方。本文重点提出了齿轮副最小侧隙与润滑方式无关而与齿面粗糙度有关的新论点,同时对各影响因素逐一进行分析,提出了新的计算公式。     

相对公差等级法解尺寸链

目前在解尺寸链设计计算方面,常沿用“等公差法”或“等公差等级法”,而后依据各组成环功能要求及其结构的工艺性进行适当的调整。有时,这种调整数值可能很大。现在此文介绍一种依据各组成环的功能要求及其结构的工艺性预先假定各组成环的公差等级系数进行计算,然后再进行圆整式的调整,这样才比较合理。     

Effects of Dimensional Tolerances on the Friction Power Loss of Hydrodynamic Journal Bearing System

According to the dimensional tolerances on hydrodynamic journal bearing system, a nonlinear oil film force model was established,and the Reynolds＇ equation was solved by adopting finite difference method. In order to fulfill different dimensional tolerances in the system,adopting 2kfactor design and using the eccentricity ratio corresponding to the stability critical curve,the effects of the friction power loss brought by the dimensional tolerances of the dynamic viscosity,bearing width,bearing diameter and journal diameter were analyzed. The effect on dynamic characteristics of the hydrodynamic journal bearing system was quantitatively analyzed,and the nonlinear dynamic analysis, modeling and calculation methods were studied while considering the manufacturing tolerances. The results show that in contrast to the impacts of the tolerances in journal diameter,dynamic viscosity and bearing width,the bearing diameter tolerance would lead to the rise in the power loss, and the dimensional tolerances have different degrees of impacts on the journal bearing system. The friction power loss decreased as the eccentricity ratio increased, and when the eccentricity ratio was 0. 695 the power loss came to the minimum.The investigation would find the best solution and reduce energy consumption,then control varieties of nonlinear dynamical behavior effectively,and provide a theoretical basis for hydrodynamic journal bearing system in parameter design.     

Order affine completeness of lattices with Boolean congruence lattices

This paper grew out from attempts to determine which modular lattices of finite height are locally order affine complete. A surprising discovery was that one can go quite far without assuming the modularity itself. The only thing which matters is that the congruence lattice is finite Boolean. The local order affine completeness problem of such lattices L easily reduces to the case when L is a subdirect product of two simple lattices L ₁ and L ₂. Our main result claims that such a lattice is locally order affine complete iff L ₁ and L ₂ are tolerance trivial and one of the following three cases occurs:

分析双Amici棱镜角度误差对色散的影响

双Amici棱镜为复合棱镜结构,作为成像光谱系统中的分光元件,避免了单棱镜色散结构存在的多种问题。双Amici棱镜的加工生产要对其各个角度提出生产指标,而角度误差对于光谱成像系统的色散性是有影响的。针对一种编码孔径成像光谱仪,设计了符合性能指标要求的双Amici棱镜,并从光线追迹的角度出发,计算得到双Amici棱镜色散的数学模型。针对给出的一特定光学系统中的棱镜结构推导了棱镜各个角度单独对线色散的影响,并分析给出各个角度构成的误差链对线色散的综合影响,最终给出了棱镜的生产指标。分析结果有助于指导系统中该棱镜的加工生产。     

有向功能关系图OFRG功能实现的代数方法

以代数、图论为工具,在描述机器装配的有向功能关系图（ＯＦＲＧ）基础上,引入多级ＯＦＲＧ、推广铰、跨接向量、连接向量、零（部）件向量等概念;提出一套ＯＦＲＧ结构分析、链路方程建立的方法。     

Study of the dependency of spectral radiance factor and colorimetric values on geometric tolerances

The CIE has recommended geometric tolerances for the illumination and collection of light in the measurement of reflectance and radiance factor for colorimetry. This investigation is a pilot study to examine the range of results obtained from the measurement of the radiance factor and colour of reflectance standards over these geometric tolerances.     

A study on a microring structure for practical devices

We propose a microring structure based on non-identical waveguides for the implementation in practical devices. Our design pays attention to aspects such as fabrication tolerances and fiber coupling efficiency. A detailed study has been carried out on the coupling between the non-identical waveguides in the analyzed structure.     

CAD系统中公差与配合标准信息处理与TID模块的研制

在分析国家标准《公差与配合》各部分数据构成关系的基础上，对ＣＡＤ系统环境下公差与配合标准数据的建库、检索和调用方法等问题进行了探讨，提出了一种全面、准确、高效的公关与配合标准数据处理模式；并在此基础上，完成了ＴＩＤ软件模块的研制。