Page 152 - Gear Technology Solutions

Figure 13 shows the analysis results of a straight bevel gearset with a ratio of 2.9
with a proportional pinion profile shift coefficient of X1 = +0.7 and a proportional
gear profile shift coefficient of X2 = +0.7. The positive profile shift in both members
increased the tooth contact in profile direction and accordingly doubled the active
working profile compared to the baseline. The lost areas at root and top are
reduced versus the baseline. A gearset according to Figure 13 will have a reduced
root bending stress and a reduced flank surface stress compared to the gearset
versions in Figures 2 and 12.

Figure 13: Ratio = 2.9, Ease-Off (left) and Tooth contact (right) for
X1 = 0.7 and X2 = 0.7

Example with Miter Ratio 1.0

Figure 14 shows the analysis results of a straight bevel miter gearset with no
profile shift (X1 = 0.0 and X2 = 0.0). The Ease-Off surface to the left represents
the consolidated length and profile crowning of a pair of meshing teeth. To the
right in Figure 14, the tooth contact area and the active working profile are shown.
The lost root area consists partially of the root fillet radius and partially of kinematic
undercut of the gear tooth. The lost top area represents kinematic undercut of the
pinion tooth. Figure 14 is the baseline for the comparisons in the following Figures
14 and 15,

Figure 14: Ratio = 1.0, Ease-Off (left) and Tooth contact (right) for
X1 = 0.0 and X2 = 0.0

Figure 15 shows the analysis results of a straight bevel miter gearset with a V0
profile shift (X1 = 0.7 and X2 = -0.7). To the right in Figure 15, the tooth contact
area and the active working profile are shown. The lost root area has doubled

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