Page 186 - Root Cause Failure Analysis
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174 Root Cause Failure Analysis
Figure l&I Example of a spurgear (Neale 1993).
in the same direction. The internal gear is a wheel that has teeth cut on the inside of its
rim and the pinion is housed inside the wheel. The driving and driven members rotate
in the same direction at relative speeds inversely proportional to the number of teeth.
Hekal
Helical gears, shown in Figure 14-4, are formed by cutters that produce an angle that
allows several teeth to mesh simultaneously. Helical gears are superior to spur gears
in their load-canying capacity, quietness, and smoothness of operation, which results
Figure 14-2 Example of an internal spur gear (Neale 1993).
