Page 159 - Gear Technology Solutions

Figure 3: Ease-Off and tooth depth dimensions of a Zerol design with 0°
spiral angle at midface

If a Zerol design has 0° spiral angle and 20° pressure angle, the slot depth ta-
per is extremely large. The Ease-Off and tooth depth proportions are shown in
Figure 3. Because of the large face width of more than 43% of the outer cone
distance, the Ease-Off looks exotic at the toe with a reversed crowning. This
problem can be solved by entering different control factors, or by using the se-
lective crowning option for fine tuning the Ease-Off. The tooth depth propor-
tions (below the Ease-Off) show an extreme taper between heel and toe,
which makes the tooth profile almost pointed at the toe. This problem will dis-
appear when a larger spiral angle is used. If the spiral angle should stay at 0°,
then only a shortening of the face width can eliminate the pointed toe profile.
Figure 4 shows the Dimension Sheet of this design.

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