Optimization of contact stress for the high contact ratio spur gears achieved through novel hob cutter

High contact ratio gears are used to minimize the stresses generated on the tooth surface. This research article represents an idea to enrich the contact strength of gear drive using novel high contact ratio (NHCR) spur gear. The increase in contact stress leads to contact fatigue failure, reducing the power transmission capacity of the gear drive. To reduce contact fatigue failure, contact stress needs to be reduced. A high contact ratio spur gear is developed using the novel hob cutter with variable tooth thickness to minimize the contact stress. For a novel hob cutter, the tooth thickness coefficient is greater than 0.5, while the thickness factor of a conventional hob cutter is 0.5. The maximum contact stress is determined through finite element analysis. In addition, a parametric study is executed for the gear parameter such as gear ratio, gear teeth, pressure angle, addendum factor and addendum correction factor to determine optimum contact stress.