Camera and elevator: what they have in common

1. Step 1. Camera — has part — Shutter. A shutter.
2. Step 2. Shutter — has part — Spring. A spring mechanism.
3. Step 3. Spring — is part of — Elevator safety brake. Springs throw out the catches when the rope goes slack.
4. Step 4. Elevator safety brake — is part of — Elevator. Otis’s safety brakes.

Open Evothings