Avalanche airbags use the same (or similar) phenomenon to inflate to a larger volume than the compressed gas canister contains.
I thought it was the venturi effect, but maybe entrainment is more accurate.
New closure allows camping mattress to be inflated in seconds
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Re: New closure allows camping mattress to be inflated in seconds
#102The valve is based on the Venturi effect. The fluid flow through a constriction lowers the pressure at the constriction point. An inlet at the low pressure point will allow addition fluid at atmospheric pressure to enter through the inlet in the constriction thus adding to the total fluid through the outlet. Pretty clever use of fluid dynamics!
Avalanche airbags use the same principle to inflate larger than the volume of compressed air in their canisters.
Re: New closure allows camping mattress to be inflated in seconds
#103I'm afraid there's already a matress that does this. It's from exped, I own one and it's awesome, and better implemented than this because you're only inflating a small pump sack, and can use it to build pressure in the mattress. Here's a video: http://www.exped.com/exped/web/exped_homepage_na.nsf/b43popu...
Seriously, this is totally different.
Exped has a separate sack that you squeeze pump multiple times over. While the OP was just "blow air in" style big opening.
Looks to be about a ten fold difference in effort and time.
Just look at the two videos - can you say with a straight face that they're doing the same thing?
Re: New closure allows camping mattress to be inflated in seconds
#104I don't get all the negative, visceral reactions to this product.
Who cares if the physics/technology is "breakthrough"?
It's clear that this is being positioned as a suitable alternative to the battery operated pumped up mattress. The ones sold in Walmart, Target, etc.
I own one of those, and they are a pain to deal with. This looks awesome.
Who cares if there are others out there already - that proves that the market exists and the technology is feasible. My concern with this is, given that I don't understand the technology behind it, and I have never seen it before - is that it is too fanciful to work. i.e. is this another "Kickstarter fraud"?
The presence of existing products on the market that use similar technology is surprisingly re-assuring.
If I were an avid camper, I would definitely buy this.
Re: New closure allows camping mattress to be inflated in seconds
#105Ah, closures. Is there anything they can't do?
Re: New closure allows camping mattress to be inflated in seconds
#106Earlier quoted context omitted.
not new by a long shot Prove it. Paste a link to an inflatable with an integrated high-speed air filler that doesn't require anything but your mouth to operate. edit: I will add that this invention is clearly new compared to the pumpbag because it is a single device taking advantage of pressure gradient. The pumpbag only uses pressure gradient to fill the pump; force from your body after the fact provides the pumping…
Sure, but the reason that the Exped uses a bag which you pump is that you can increase the pressure in the mattress significantly. So, OK, I'll agree with you that this is new because the pump is integrated. But I doubt it'll turn out to be superior. And so I can't post a link to a similar product because the similar products don't do it that way for a reason.
Personally, I'm not terribly concerned about mattress air pressure once it reaches a certain point. I'm more concerned about the mattresses ability to maintain a certain level of air pressure. My use case would probably be camping/hiking and if the windcatcher can provide enough pressure for my body to stay suspended off of the ground, then I'm fine, personally. I do realize that's not necessarily everyone's criteria, though.
I'll also say that I really dig the way the schnozzle works and I'd probably prefer that, mostly because of the dual use as a stuff sack, and that it gives me more options when it comes to mattress selection.
I just like that there are people trying different ideas out, and I get to recline in my chair and see what sticks.
Re: New closure allows camping mattress to be inflated in seconds
#107The Kickstarter itself says: "You're supporting an entirely new type of technology that has the potential to inspire new ideas and future innovative products." No, you are not. Exploiting the pressure difference like this for inflation is not new by a long shot. Just pop down to REI: http://www.rei.com/product/829645/exped-schnozzel-pumpbag Edit: read rest of replies below for clarification.
> The Kickstarter itself says: "You're supporting an entirely new type of technology
> No, you are not. Exploiting the pressure difference like this for inflation is not new by a long shot.
Did you watch the REI video? It's certainly not giving the same impression. The REI video is cumbersome and tedious. You're basically netting air, then sealing it into a large bag, then smushing the bag to push the air into the mattress. By contrast, the new process feels like a single elegant action.
Watching the two videos, the process feels utterly different: sealing and squashing a pillow vs inflating with a breath into a funnel.
Re: New closure allows camping mattress to be inflated in seconds
#108Earlier quoted context omitted.
Example of the the baader-meinhof phenomenon? I learnt about this it a few days ago, as its the same phenomena used by Brain Brushwood in this weeks scam school - http://www.youtube.com/watch?v=at0xRBacJF8 where he attributes it to the 'bernoulli effect'.
I don't think you mean Baader-meinhof ( http://en.wikipedia.org/wiki/Baader-Meinhof_(disambiguation) ) They do mention the bernoulli effect in the Kickstarter video
From Damn Interesting - http://www.damninteresting.com/the-baader-meinhof-phenomenon... Although, in my circle, it will forever be known as the Pizza Stone Phenomenon.
Re: New closure allows camping mattress to be inflated in seconds
#109Nice concept, but I'm wondering how inflating a mattress in this manner will allow you to achieve the pressure needed to support your weight.
By laying on it, you're compressing what's in there, and it pushes back on you. There's no need to ever inflate a mattress like a bicycle tire.
This is not a comment from a hiker. You do need to pressurize sleeping pads. If you're older than 25, you do, trust me.
Re: New closure allows camping mattress to be inflated in seconds
#110Earlier quoted context omitted.
I agree, but this is not new by a long shot and it's not even new in the domain where it is being applied. So I stand by my statement that the claim being made in the Kickstarter is untrue.
not new by a long shot Prove it. Paste a link to an inflatable with an integrated high-speed air filler that doesn't require anything but your mouth to operate. edit: I will add that this invention is clearly new compared to the pumpbag because it is a single device taking advantage of pressure gradient. The pumpbag only uses pressure gradient to fill the pump; force from your body after the fact provides the pumping…
Besides being able to achieve higher pressure (which I agree isn't terribly important), the Expeds need extra force to inflate because they're filled with down or synthetic insulation, which dramatically increases their insulating value. A R value of 1.0 isn't useful as a sleeping pad for hiking except in really warm climates. 2.5 is a realistic minimum for a three-season pad.