Define interference in involute gears.

Question

        1. Define interference in involute gears.

        2. How do you prevent interference?

     3. Determine the minimum number of teeth required on a pinion, in order to avoid interference which is to gear with an equal wheel. The pressure angle is 20⁰ and a standard addendum of 1 module for the wheel may be assumed.                                 2+3+10=15

1. 1. Sketch the arrangement of a reverted gear train comprising of gears A and D mounted on co-axial driving and driven shafts, respectively. Gears B and C are mounted on a parallel counter shaft to mesh with gears A and D, respectively.
2. The speed ratio (driving speed ¸ driven speed) in the reverted gear train of above arrangement is to be 14. The module pitch of gears A and B are 3.125 mm and of gears C and D are 2.5 mm. Calculate the suitable numbers of teeth for the gears. No gear is to have less than 24 teeth. The centre distance between the counter-shaft and driving shall is 200 mm. 5+10=15