• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.5
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• pp.572-578
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• 1985

A composite gear with involute-circular are tooth profile and a tooth profile of the rack to cut this gear are theoretictically obtained. The composite gear has involute tooth profile in the vicinity of pitch point and has circular arc tooth profiles at addendum adn dedendum. The contact ratio(M$_{c}$), chordal tooth thickness (chordal tip tooth thickness S$_{t}$, chordal root tooth thickness S$_{t}$) of the composite gear are compared with those of involute gear. When module, number of teeth and pressure angle eqaul, S$_{t}$ of composite gear is much larger than that of involute gear. Under the same conditions, S/sib t/ and M$_{c}$ of composite gear become smaller than those of involute gear.lute gear.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.6
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• pp.870-875
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• 1986

In this study, full-rounded tip curve of rack and its mating fillet curve of pinion in Involute-circular arc composite tooth profile are derived. Mechanical characteristics are calculated analytically, i.e., Specific sliding, Nominal bending stress at working root circle and the Contact factor of the arc of contact in circular arc part to the arc of double contact. These characteristics compared with standard involute tooth profile are improved in circular arc part of composite tooth profile. To obtain more efficient composite tooth profile, we studied these characteristics with regard to the changes of unwound angle and radius of circualr arc. And a design method of composite tooth profile is suggested. Composite tooth profile are compared with standard involute tooth profile.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.2
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• pp.198-204
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• 1987

In a new involute-circular arc tooth profile which is composed of an involute curve in the vicinity of pitch point, a circular arc in the addendum part, and a curve in the dedendum part which is generated by the circular arc profile of mating gear tooth profile, the tooth contact stress is calculated analytically and the root fillet stress is calculated by the finite element analysis. The root fillet stress and the Hertzian contact stress of composite tooth profile gear are decreased with increasing the pressure angle and with decreasing the radius of circular arc and unwound angle. Compared with the standard involute gear, the root fillet stress is decreased by 2-15% and the Hertizian contact stress is decreased by 6-24%.