If the centre distance of a mating gear having involute teeth is varied within limits, the velocity ratio

Explanation:

For an involute profile gears:

• During the action the pressure angle remains constant.
• No fluctuating load on support as well as no fluctuating torque output.
• With the change in the center distance, the law of gearing is still satisfied, however, the operation becomes noisy.
• The center distance for a pair of mating gears can be varied within limits without altering the velocity ratio.