Thanks for educating me, and others, for a great use of a Burdon tube!
I had never seen this before. My experiences were using them in alarms.
Maybe the NFL could use some! ;^)
Sure. It’s a fascinating clock and mechanism. Strictly speaking, it’s a bellows, not a Bourdon tube. The Bourdon tube uses differential pressure to very slightly straighten out a curved tube which is translated to motion. The Atmos has used three power sources (oldest to newest):
* mercury-in-glass expansion device (temperature changes alone)
* mercury and ammonia bellows
* ethyl chloride power (current)
I think all three used a bellows.