Contact Pressure Estimates of Tooth Surfaces of Gear Couplings

Abstract

Abstract Recent demands for gear couplings are to reduce the backlash and to increase the shaft angle limit. On coping with these demands, the tooth contact pressure is recognized as the trade-off problem. In the traditional estimation of tooth contact pressure, the deflection of tooth is calculated by using the formula for spur gear that has long contact bearing in the face width direction, although gear coupling has it in the tooth depth direction. And, the Hertz depression of the tooth surface is estimated as that of the infinite plane. Additionally, the traditional methods don’t consider about the edge contact on the tip or end of tooth. A successive approximation method is established to find the load distribution on the mating teeth surfaces. As for the effect of the edge contact on the tip or end of tooth, it is cleared that the contact pressure distribution deforms itself severely, but the maximum pressure is almost constant. The expressions estimating the maximum pressure and the displacement of tooth base are constructed for 6 parameters as follows; total load coefficient, relative curvature of teeth surfaces, tooth module, ratio of tooth height to face width, angle of tip contact and deviation of end contact.