Research On The Worm Transmission With Line Contact And Its Application In Grinding Gears

According to the principle of spatial skew axis helical gearing,when the common enveloping surface of the two gears tooth flank are rack tooth flank with a zero tooth profile angle,the centre distance of the two gears is the sum of two base circle radius.In that case,the common enveloping surface of the two gears will contact with a straight line.If one of the two gears have tremendous base helix angle and few teeth,alternate angle of the two gears is a right angle,it becomes worm transmission.The characteristic of this worm transmission is that the transmission are essentially helical involute gears,so the worm and wheel are in contact with a straight line.This is distinct from traditional worm transmission with curve contact.Second,when a pair of helical involute gears drive,it has all the advantages of gear transmission,and can also achieve large gear ration,machining method are the same as gear.Compare to the traditional worm transmission,because of the work surface are developable surface,so it is easy to achieve tooth and tooth surface high precision.To create the conditions for high-precision drive.The characteristics of the structure and manufacturing process of the transmission pairs of worm drive with straight line contact that can achieve precise transmission were analyzed.The theoretical arithmetic and architecture design of the worm drive were introduced.In the foundation, a new grinding gears technique with the new worm grinding is proposed.When the trace line of the worm tooth surface is longer than the gear width,gear grinding with worm grinding wheel will without axial feed.This grinding method has simple structure, and higher efficient in this technology.It's suitable for grinding gears and honing gears in large numbers.Fine grinding can be used to this worm because of the work surface are developable surface.It is favourable to manufacture of harden steel, plate CBN.And it can also be easy to repair,so it can reduce the cost.The principle and method of the technique were discussed in detail, in which double worm grinding wheel would be used. And how to realize the structure of the machine and grinding feed,grinding velocity formula were given.The determination of design parameters of this new worm are according to the size of base circle which is different from the tradition gears.This paper presents the determination of design parameters are under the principle of non-intervention,making the worm has sufficient rigidity,strength and good economic.In the foundation,We choose CNC lathes and special tools to manufacture this worm. Worm processing should ensure distance of the starting line contact of both side involute helicoid.In this studu,not only in theory for this new type of worm drive,but also manufacture a pair of worm for testing. Simulating the force of the grinding processing based on ADAMS.