Gear mechanism can be used to transmit the motion and power between any two shafts in space, and its peripheral speed can reach 300m / s. It is the most widely used transmission mode in modern machinery. It can realize the same direction and reverse transmission, parallel shaft transmission, intersecting shaft transmission or staggered shaft transmission. It has the characteristics of large transmission power range, high efficiency, accurate transmission ratio, long service life, stable operation, safe and reliable operation, etc. There are many kinds of gears. According to the shape of the tooth profile curve, gears are divided into involute, cycloid and circular arc gears. Among them, involute gears are easier to manufacture and more stable to drive, and are the most widely used. However, in the actual design, the accurate modeling of involute gear is a major difficulty, mainly in the drawing of involute sketch of tooth profile. The traditional gear design process is cumbersome, the tooth profile accuracy is low, and the design time is long. With the development of computer aided design and manufacturing technology, using some three-dimensional design software to design involute gears can save design time, ensure the accuracy of tooth profile and predict the interference phenomenon during gear assembly. At present, the modeling methods based on SolidWorks software mainly include using solidworkstoolbox plug-in and other design libraries to call involute gears and obtain the required gears by modifying some set parameters. This method is suitable for simple involute gear transmission motion analysis or simple mechanism drawing with low requirements for involute accuracy. You can also use CAXA electronic drawing board, geartrax, Pro / E and Mindy tool set to generate involute gears. Using arc or straight line to fit involute or tooth root transition curve, the generated tooth surface profile is approximate involute, and the accuracy of tooth profile is low, which is not conducive to the subsequent dynamic simulation and finite element analysis of involute gear.
Based on the three-dimensional design Software Solidworks and involute gear parameter formula, involute formula, combined with the function of software equation, the parametric accurate modeling of involute gear is realized. Parametric design mainly uses the functions of sketch design and dimension drive to modify the shape of the figure and accurately locate the size of the figure by changing the geometric parameters of the figure, so as to obtain complex involute gears with high accuracy and meet different design requirements. It is of great significance to the machining of high-precision involute gears, kinematic and dynamic analysis of gear trains and finite element analysis in the process of mechanical design and manufacturing practice.