Involute profile is preferred over cycloidal profile because

Question

Question

This question was previously asked in

JKSSB JE ME 2015 Official Paper

Answer 1

Explanation:

The involute profile of teeth is preferred over the cycloidal profile of teeth because only one curve is required to cut.

Involute teeth have a number of benefits as compared to the Cycloidal profile as mentioned in the given table.

Cycloidal teeth	Involute teeth
A cycloid is the locus of a point on the circumference of a circle that rolls without slipping on the straight line.	An involute is defined as the locus of a point on a straight line which rolls without slipping on the circumference of a circle.
It involves a double curve for the teeth, epicycloid and hypocycloid. This complicates the manufacture.	It involves a single curve for the teeth resulting in the simplicity of manufacture and tools.
The pressure angle varies from a maximum at the beginning of the engagement, reduces to zero at the pitch point and again increases to a maximum at the end of engagement resulting in the less smooth running of the gears.	The pressure angle is constant throughout the engagement of teeth. This results in the smooth running of gears.
Owing to the difficulty of manufacture, these are costlier.	These are simple to manufacture and thus are cheaper.
Exact centre-distance is required to transmit a constant velocity ratio.	A little variation does not affect the velocity ratio.
The phenomenon of interference does not occur at all.	Interference can occur if the condition of the minimum number of teeth on a gear is not followed.