Unformatted text preview: sin 2 f where rb denotes radius of base circle, c represents center distance (O1, O2), f stands for pressure angle (actual, not nominal). o To avo id t eet h int er ference in gears, t he fo llo wing equat io ns can used to find o ut t he smallest / largest number on spur/helical pinio n and gear: For a given reduction ratio, the smallest number of teeth on the spur pinion without interference 2 k can be found by: N p = ( + m 2 + (1 + 2 G ) sin 2 f ) , where, k = 1 for fulldepth m m (1 + 2 G ) sin 2 f m teeth, and k = 0. for stub teeth, m is reduction ratio, f is the pressure angle. 8 G For a specified pinio n, the largest number of teeth on the spur gear with interferencefree will be 2 N p sin 2 f - 4 2 k N G = 4 - 2 N p sin 2 f k For a given reduction ratio, the smallest number of teeth on the helical pinion without 2 cosy k interference can be found by: N p = ( + m 2 + (1 + 2 G ) sin 2 f t ) , where, m m (1 + 2 G ) sin 2 f t m k = 1 for fulldepth teeth, and k = 0. for stub teeth, mG is reduct ion ratio, f is the tangent ial 8 t pressure angle, y is...
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- Fall '09
- gear, po int, pitch diameter, ang le, Pitch circle Pitch