Atmos workings

[daxwc]

Interesting site.

http://www.atmosadam.com/howitworks.html

Anybody know what gas they using for expansion?


tks /

[Fletcher]

Altimeters & other aircraft instruments [before the digital age] used the same principle i.e. changes in barometric pressure brought about by change in altitude caused a trapped amount of air [at sea level pressure 1.225 kg/M^3] to expand or contract depending on outside temperature & static pressure [altitude] - these were calibrated to readings so they were useful to the pilot - N.B. altimeters had to be reset to the QNH [local air density] every time you went flying or had an area or weather update], standard practice.

Other gases could be used [probably inert gases like argon or nitrogen] & differently calibrated for temperature expansion & contraction, assuming the clock remains at sea level or whatever datum is used when it is calibrated.

EDIT: Cox's clock was built circa Bessler & it used Barometric pressure differences as wx patterns moved thru - also IIRC the first hydrostatic devices were built by a german fellow about or before Bessler - he used 10 meter high water filled pipes on the side of a mountain to gauge the rise & fall of the head according to pressure differences.

[terry5732]

The page you linked is somewhat wrong

Atmos clocks work on barometric pressure - not temperature differential as that page stated

The earliest Atmos clocks used ethyl chloride. They have something less toxic and corrosive now.

There is very little power gained in these. If they were a hand wound spring, they would run for about four years. It is more a matter of movement efficiency rather than a great free energy.

[jimmyjj]

i wonder if you could fit a giant atmos bellows in besslers wheel .......how big is the largest atmos bellows ever made ？ my doors were slamming the other day with a lot of force from changes in air pressure,.........

[ovyyus]

Anybody know what gas they using for expansion?

Not a gas, a vapor. Ethyl chloride.

[getterdone]

Cox's clock, the one called ''Perpetual Motion'', used mercury. It ran for over 30 years, until someone spilled the mercury while moving it.