Question

Which of the following is not true about concentricity of teeth?

(a) Fluctuating velocity will be noticed when not concentric

(b) Can be checked by using projector

(c) Inaccuracy of parts when not concentric

(d) Should be tested to ensure the proper heat treatment

I got this question in a national level competition.

Asked question is from Gear Measurement in portion Measurement and Testing of Gears of Engineering Metrology

Answer 1

Correct option is (d) Should be tested to ensure the proper heat treatment

To explain: Concentricity of teeth is an important item and should be checked to ensure that the set up and equipment is in good order. When teeth are not concentric then fluctuating velocity will be noticed on the pitch line while transmitting motion.