If you need an illustration of exactly what i mean let me know and i will make some quick visio diagrams.
How can i make sure a water tight cap is in place
QuoteHow can i make sure a water tight cap is in placestep 1: Rewrite the problem as the solution ==> fill the system with water and if it leaks it is not in place.Step 2: make it realistic==> fill it with air and if the pressure goes up the cap is in place, if not its not.Check - www.triz40.com - for pattern based problem solving (might be not the best site to start but OK)
Why not orient the switch so that it does not present an end stop to the cap?
1: The air filled can is full of electronics, filling it with water each time i place the cap kind of defeats the purpose of needing to keep the water out.2: We do a vacuum test to check the rest of the seals, but having a port that i can use to induce air means i have another hole to check and effectively doubles my problem. Then i would have to make sure two caps are in place.
Quote from: PeterH on Mar 09, 2012, 01:31 amWhy not orient the switch so that it does not present an end stop to the cap?Interesting. How so?
@2: you don't need an extra hole, on contrary I would propose a small compressed C02/air cylinder, a valve and a pressure sensor and some bits to control it. Yes it means some additional electronics. After the cap is closed the valve opens to raise the inner pressure by X%. If there is any leakage wherever it will be detected in contrast of just detecting a switch has been pressed the right way.Additional, if there is a very small leakage some overpressure might prevent water leaking in (keep it local)
Hard to know what PeterH had in mind but a lever microswitch held such that the rod passing it deflected the lever would be a very basic way:____ | |Sw |\ | |___| \| | | |An optical path broken by the rod would be another way.
I suspect it wouldn't do anything really because it's a maintained 1 atmosphere of pressure inside the container regardless of depth.
Looking for a way to have two wires connected when no cap is present and open when the cap is present.