The crowning curve is {TAIL ~ exponential function} which causes the contacting point to move toward the tooth width end as the displacement increases and the radius of curvature becomes larger as {HEAD ~ the point} on the curve approaches to the tooth width end, so that even when the contacting gear number decreases when displaced, the increase in the contacting stress is suppressed and a larger power can be transmitted as compared to the conventional design 
The crowning curve is { TAIL ~ exponential function } which causes the contacting point to move toward the tooth width end as the displacement increases and the radius of curvature becomes larger as { HEAD ~ the point } on the curve approaches to the tooth width end , so that even when the contacting gear number decreases when displaced , the increase in the contacting stress is suppressed and a larger power can be transmitted as compared to the conventional design
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