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Mouth operated valve?

Posted: Mon Jun 08, 2015 11:01 am
by xwrench
I've been eyeing a planishing hammer at harbor freight but from what I see, one sorta needs to use both hands to control your piece of metal. As I can't use a foot pedal I'm looking at maybe rigging up a mouth operated valve. We have people here from many industries and I may be trying to reinvent the wheel or overlooking some other solution. Any ideas would be welcomed.
Thanks

Cheers.
Eldon

Re: Mouth operated valve?

Posted: Mon Jun 08, 2015 11:40 am
by hey_allen
A low pressure differential switch and a length of hose could trigger a relay and then your hammer, if electrically controlled.
If it's a pneumatic hammer, add a solenoid valve to the air line to actuate the hammer.

Here is a switch that is marketed toward sky-divers to trigger their cameras, but there are other options on ebay. I'm not sure what pressure range you'd be best off with.
http://www.rockskymarket.com/camera-swi ... witch.html

I found the medical marketed switches being called "sip/puff switches" but they are priced as medical devices, in the $300 range. :shock:

Re: Mouth operated valve?

Posted: Mon Jun 08, 2015 12:46 pm
by xwrench
Thanks. I knew someone on here would have a good idea. That looks like just the ticket. That switch and a solenoid valve and I'll be set. I think I'll rig something similar for the pedal on my electronic piano :)

Cheers
Eldon

Re: Mouth operated valve?

Posted: Mon Jun 08, 2015 9:41 pm
by Otto Nobedder
Hey_allen,

That's brilliant!

We try to be a source of good ideas for each other, and you are in the running for a "Genie"

(That's a "genius of the year" award I JUST made up.)

That's a great example of thinking in unexpected ways!

Steve S

Re: Mouth operated valve?

Posted: Tue Jun 09, 2015 12:49 am
by hey_allen
Heh, it helps that I'd been scrounging around eBay recently trying to source a pressure switch to interlock the water cooler that I'm working on building for my CK20 torch.
(I don't want it to be easy to burn up the torch, so I'm putting in a pressure switch to keep the arc from lighting off when there isn't at least some pressure, how much yet to be decided, present on the water lines.)

That, and being a scrounge in the junk piles of salvaged and scrapped out equipment at work, including loads of pneumatic bits and pieces.

I'm just glad to at least share an idea, hopefully it works out!

Re: Mouth operated valve?

Posted: Tue Jun 09, 2015 4:20 am
by AndersK
If you use a low voltage DC coil for the solenoid you could connect one side of power source to the frame. Attach the return side of solenoid to a wire attached to your glove. When you apply pressure to the sheet you close the circuit. You could use a thin switch as wrll that would trigger when pressed against the sheet.

Buy the best ear protection you can get and invite your neighbours to BBQ before you use it first time... :mrgreen:

Allen, you should try and find a switch that trigger on flow. You'll have plenty pressure if the lines are clogged but zero flow.

Re: Mouth operated valve?

Posted: Tue Jun 09, 2015 7:31 am
by Bill Beauregard
Washing machines use a diaphragm switch to tell when the drum is full. Many can fill to more than one level. To test them I used to blow on the tube.

Re: Mouth operated valve?

Posted: Tue Jun 09, 2015 8:35 am
by hey_allen
Anders: I looked at doing a flow switch, but the only one or two true flow switches that I found, I could find no information on their trigger range. The others were flow meters, either analog or digital pulse generator types, and I am trying to keep from having to do any programming on a micro-controller to manage a welder. I just don't want to have any sensitive electronics protecting it, due to the HF noise and interference.

Bill: Good idea on the washing machine barrel switches. I looked at them initially when I was shopping for a switch, but discarded them due to the very low trigger pressures, since I wanted mine to trigger around 50 psi, not 0.5 psi. They are cheap as well.