| Less-teeth gear transmission is cylindric spiral gear transmission the pinion whichcontain one to seven gears. It is the extension of general involute helical gear transmission,which have some advantages, such as high single stage transmitting ratio, compact structure,low weight, etc and have a good application foreground. But, there is a lack of some designdata about that transmission, which limit the promotion and application of that technology. Onthe basis of analyzing the design and calculation theory of addendum modification Less-teethgear transmission, bilateral modification come forward by this article, the formula ofgeometry design calculation are deduced, the bending fatigue strength of the tooth root isdeeply researched.The main content of this article is as follows:First, the method of designing Less-teeth gear in bilateral modification come forward.Sharpened teeth which is caused by single addendum modification coefficient is solved.Second, determination method of addendum modification coefficient and tangentmodification coefficient come forward and the influence of parameters of a gear pair ontangent modification coefficient. The concept of designing Less-teeth gear in different tangentmodification coefficient come forward and is researched simply.Third, the geometry size formulas of Less-teeth gear pair is deduced, and four kinds ofdifferent modification coefficient gear pairs are designed. After contrasting sliding coefficientof the four kinds of gear pairs, the sliding coefficient of Less-teeth gear pair which is designedby way of same sliding coefficient of tooth root and different tangent modification is thesmallest.Fourth, bending strength of gear tooth of less-teeth gear transmission is researched. Thegear which contain one to two gear teeth cannot use30°Tangent method to con-firm thelocation of tooth root dangerous cross-section. After using finite element software to makestatic structure analysis of different gear fairs, the location of maximum root stress of gear which has two gear teeth is found. Through statistics, location of tooth root dangerouscross-section is found. The formulas of tooth form factor and stress modification coefficientof Less-teeth gear are deduced.Last, in order to make the design of Less-teeth gear more convenience, MATLAB is usedto make computerization of the formulas and MATLABGUI is used to make the interface.Through a practical example, a pair of Less-teeth gear is designed.In conclusion, the research results of this article provide the basic argument for furtherresearch of bilateral modification Less-teeth gear. |
