Comparing stress distribution, strain, and total deformation in contact surface for the three types of rack and pinion

Used helical gear in many engineering applications as in rack and pinion. This paper shows a study of three types of rack and pinion, these types used helical gear, the first type is single gear, the second type is double gear, and the third is herringbone gear. The research explained the distribution of stresses, strains, and elastic deformation in the contact area between all types of the rack and pinion. Some important conclusions were presented for the purpose to can be used in design such as choose a high-strength material for gear with the specified helix angle, and selected a larger face width in the gear shape is preferred, total deformation varies from one type of rack pinion gears to another. The results show, total deformation varies from one type of rack pinion gears to another, but It seems that the single helical gear elastic deformation is high value and the rack-pinion (herringbone gears). The best of the three types in this research is according to the values of the distribution of stresses, strains, and elastic deformations.