The thesis developed the optimization design software of geometric parameter for the worm gear including strength check module , the drawing contact lines module , the change lines of tooth thickness of worm , and the parametric modelling software for the reducer which includes parametric modelling of parts and assembly . the cad prototype system is very convenient because of its accessible interfere , simple operation and written in chinese . by input design parameters ， the cad system can make optimization design and strength check for the worm gear ， draw contact lines of tooth flank of worm - gear and change line of tooth thickness of worm ， judge if the tooth flanks of worm undercut and if the sideward tooth of worm - gear hob come to a point ， make project design and structure design for the reducer and draw its 2d parts and assembly 研究和开发了平面二次包络环面蜗杆传动的参数优化设计和校核软件系统：包括几何参数设计计算模块，强度校核模块，绘制齿面接触线模块，蜗杆齿厚变化曲线模块和蜗杆根切判别模块；开发了平面二次包络环面蜗杆减速器外形与结构尺寸数据库以及传动效率数据库，建立了平面二次包络环面蜗杆传动公差及极限偏差数据库；开发了平面二次包络环面蜗杆减速器参数化建模软件：包括零部件的参数化建模模块和装配图的参数化建模模块，其中零部件的参数化建模包括蜗杆轴系的参数化建模、蜗轮轴系的参数化建模、箱体的参数化建模、端盖的参数化建模、轴承的参数化建模和其它零部件的参数化建模软件模块。
On the condition of “ many - head ” and “ small drive ratio ” ， the plane double enveloping hourglass worm can not settle the problem of undercutting and sharpening simultaneously . it has devoted to a new type hourglass worm _ sphere double enveloping hourglass worm . the coordinate system is established according to the frock . the meshing equation and the tooth equation of worm and gear have been developed and the distribution of contact line on gear tooth is analyzed . to evaluate the meshing quality ， four meshing quality indexes and five original parameters are put forward . through mass programming computing ， the relations between meshing quality and original parameters are derived and depicted by graphs 考虑到平面二次包络环面蜗杆传动在多头小传动比条件下根切与齿顶变尖的矛盾很难同时解决且啮合性能较差，介绍了一种新型环面蜗杆传动? ?球面二次包络环面蜗杆传动.在研究过程中，根据工装建立了坐标系，根据一二包过程的运动关系推得了啮合方程和蜗杆与蜗轮的齿面方程，分析了蜗轮齿面上的接触线分布.为了评价啮合性能，提出了4项性能指标和5项原始参数，通过大量编程计算得到了啮合性能指标与原始参数之间的关系，并以图表直观的表示
