The Transmission Theroy Of Cylindrical Gears With Curvilinear Tooth Trace

Gear mechanisms have been used extensively in various industrial applications, such as gear boxes on vehicles, machine tools, speed-reducers and various transmission systems. Basically, gears are used to transmit a constant speed ratio between the input and output shafts, and to magnify or reduce the torque with the inverse of the ratio. Although the technologies for the design and manufacturing of gears have been improved quite a lot in these few decades, however for some applications, the problems of backlash, edge contact and over-stress are still exist. Thus, researches on developing innovative gears with better characteristics are necessary. Gear manufacturers and designers continuously attempt to develop more compact and higher capacity gear pairs.Among the results of these researches, cylindrical gears with curvilinear tooth trace have merits as follows: higher bending stress, low noise, better lubrication conditions, and no thrust forces. So this kind of gear can be considered to substitute the helical gear and herringbones. For studied only a few years, it still has some problem in theory and application, so it is necessary to have a further study on it.Based on conjunction theory, the models for gear manufacturing is developed, and the equation of the gear surface is gained by the equation of rack cutter. The contact line in manufacturing and the tooth profile of the gear is also discussed based on the equation of the gear surface.The curvature interference of the gear and the influence of radius of the mill-cutter, axial misalignment, and center distance on meshing are analyzed. Based on these analyses, propose two methods to achieve point-contact: to change the radius of the mill-cutter and increase the center distance.The calculation of tooth contact stress and the bending stress is discussed. The equation of the bending stress of the gear is developed and the arcuate domino effect is analyzed, comparing with ordinary involute gears.The equation of pressure angle, width coefficient, and contact ratio are calculated and the influences of these parameters on contact are analyzed. Based on ordinary involute gear, the diametral deflection principle of curvilinear-tooth...