Question

A toy with reciprocating movement is shown. As the wheels of the toy rotate, the head is required to reciprocate. If given options are indicative of conversion of rotary to linear motion using a disc located at the centre of the wheel shaft, which option will result in the required movement when the toy is pushed forward? Assume a working spring loaded cam mechanism in the relevant option/s.

• A. Fig A
• B. Fig B
• C. Fig C
• D. Fig D

Hint:

Snail cams are the most common mechanism in animated toys because they store energy gradually over a full rotation and release it instantly, creating a lively and realistic animal motion.

Answer 1

The Correct Option is A

Step 1: Need rise and fall.
Reciprocating motion requires an eccentric or offset cam so the follower lifts once per turn.
Step 2: Pick the profile.
The offset disc gives smooth up-and-down follower travel.
\[ \boxed{\text{Option 1 (Fig A)}} \]