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New closure allows camping mattress to be inflated in seconds

kickstarter.com

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Re: New closure allows camping mattress to be inflated in seconds

#81

Post by dnr »

salimmadjd wrote: post #76
baudehlo wrote: post #46

I'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...

I wish you had shared this sooner before I made my purchase :) I noticed the R value of the kickstarter pad. But at 3+ inches it has to be above R:1. My guess is they haven't tested it so just to be safe they have put an R value of 1. Just look at other bags or pad at similar thickness and their R value should at least be in 3-4 range.

You need a lot of interior baffling or insulating material stuffed inside an air mattress to get the R value up to 3 or 4. In a big open tube you get convection, which speeds up heat transfer.

Note that the original NeoAir, which is about the same thickness, is only R 2.5, but that's with a lot more interior baffles plus reflective coating on the inside. The exped mats are filled with down or synthetic insulation.

Re: New closure allows camping mattress to be inflated in seconds

#82

Post by frakkingcylons »

jgrahamc wrote: post #58

The 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.

It may not be the first implementation of this kind of technology, but if it does it better and we haven't heard of the others, then it doesn't matter.

Re: New closure allows camping mattress to be inflated in seconds

#83

Post by jjoonathan »

jgrahamc wrote: post #58

The 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.

There are also entirely passive self-inflating mattresses out there. They're filled with (solid-gas) foam that expands when you open the valve. Close the valve and it's ready to go. You store the energy for pumping when you deflate the mattress by rolling it back up. It's much easier to provide energy by sitting on something than by blowing into it :)

I don't know the brand name, only that they were old and worn by the time I was using them as a kid. They must have been commercially available around 1990.

Re: New closure allows camping mattress to be inflated in seconds

#84

Post by bazzargh »

nmcfarl wrote: post #50
bazzargh wrote: post #36

The stuff about inflating with your mouth is a bit of a straw man. If you inflate say a Thermarest NeoAir or a Packraft you're more likely to use something like an Instaflator now: https://www.youtube.com/watch?v=yJLVYfg88TE (Thermarest have their own variant on the bag inflator for the neoair - but the principle's the same)

The backpacking mattresses are still inflated by mouth - I’m certainly not carrying another 2 oz on my back for a week just to save a minute on inflating. And neither are any of the folk I go into the backcountry with. But this mattress is not aimed at us either - it weighs in at 24 oz with an R value of 1! So perhaps the Thermarests owned by people who’d buy this are currently being inflated by Instaflators...

I did say 'like' an Instaflater - it's the mechanism I meant. The thermarest pump sack doubles as a stuff sack, so it's not dead weight like the Instaflater.

I'm a bike tourer, not a backpacker, so I tend to shave weight when I can drop a pound not an ounce - carrying that isn't a big deal.

But yeah, 24oz and R 1 is pretty bad.

Re: New closure allows camping mattress to be inflated in seconds

#85

Post by frenchy »

bazzargh wrote: post #36

The stuff about inflating with your mouth is a bit of a straw man. If you inflate say a Thermarest NeoAir or a Packraft you're more likely to use something like an Instaflator now: https://www.youtube.com/watch?v=yJLVYfg88TE (Thermarest have their own variant on the bag inflator for the neoair - but the principle's the same)

I don't bother with anything but the mouth inflator for my NeoAir. It takes me a total of 15 seconds max. I'm not quite sure what all the fuss is about.

Re: New closure allows camping mattress to be inflated in seconds

#86

Post by oftenwrong »

mogrim wrote: post #68
UnoriginalGuy wrote: post #44

Earlier quoted context omitted.

I've played with Dyson's Air Multipliers in a department store and they really are that loud when you turn them up to mid-high setting. "Too loud." I wish I could recommend you a high quality fan, I've looked, and frankly it is pretty slim pickings out there. Currently I have an unbranded Chinese-made one. I'd kill for an ultra-quiet nighttime one, and pay good $$$ for it too.

Get a ceiling fan, they're usually a lot quieter.

That is because they are much bigger. In general, a larger fan can achieve the same CFM as a smaller fan, but at a lower RPM. Slower spin, quieter operation.

Re: New closure allows camping mattress to be inflated in seconds

#87

Post by finnh »

jgrahamc wrote: post #58

The 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.

Thanks for the schnozzel link! Just last night I pulled out my exped pad and thought "huh, that's going to be annoying to fill up". Problem solved thanks to your good offices.

Re: New closure allows camping mattress to be inflated in seconds

#88

Post by robomartin »

darkmighty wrote: post #77
robomartin wrote: post #48

Earlier quoted context omitted.

I haven't (and will not) invest any time doing the numbers but, a quick think about the Dyson fans leads me to conclude the whole thing is a big marketing scam. Kudos for pulling it off, but the thing ain't magic. For starters, it has blades. It definitely has blades. They are simply concealed. It's like saying my computer has no fans when the fans are not visible from the outside. Nonsense. Second, it takes a certai…

I haven't seen any checks on this, but I suspect the Dyson can probably move more air than a regular fan. It probably isn't more raw energy-efficient, but it can be more comfort energy-efficient (more comfort for the same energy), because their principle makes sense -- if you use a regular fan, you air speed is going to be dictated by the blade speed, while the amount of air depends on the area. With the dyson, they…

And I am arguing it is complete hogwash.

If a ring of air magically propels a lot more air around it, do you think a fan of the same diameter might just compel the same air molecules to follow suit?

> if you use a regular fan, you air speed is going to be dictated by the blade speed

On the Dyson air speed IS dictated by blade speed. They have a damn fan at the base pushing air through the system and they use that air to accelerate some more air around it. Again, I am not going to waste my time doing any math. My educated guess is that the efficiency, when compared to a properly designed fan of the same diameter is atrocious.

One other point, air speed coming out of a fan is not solely dependent on blade speed. Blade shape, diameter, angle of attack, duct length and even airfoil come into play.

You also have centrifugal, fans which operate under slightly different principles and can deliver airflow at greater pressure than axial fans.

More importantly, if you are trying to cool something air speed isn't always the most important criteria. The volume of air moved per unit time is extremely important. It has to be matched to the thermodynamics of the heat exchange that will happen with whatever it is you want to cool Delivering air faster and with greater volume than necessary is a waste of energy.

Re: New closure allows camping mattress to be inflated in seconds

#89

Post by JoshTriplett »

kaolinite wrote: post #41
UnoriginalGuy wrote: post #22

Earlier quoted context omitted.

Speaking of which, I wonder if they'll need to deal with patents. From what I understand Dyson has that technology wrapped up tight. PS - Dyson's fans are also terrible. Great concept, poorly executed. They wanted them to be sleek, so they used tiny motors which are LOUD making Dyson's Air Multiplier far louder than other fans WITH blades. PPS - http://www.youtube.com/watch?v=fVbEE0Qe4BQ

I'm planning to buy a Dyson Air Multiplier heater/fan very soon so this comment intrigued me. I'll be sure to go to a store to check them out in advance. I didn't really like the video you linked as I find it to be a bit of a red flag when someone calls something "overpriced", especially when they go on to be very negative about it - it almost feels like jealousy. Still, I'll look into it before I buy. I don't suppos…

I've found Vornado fans quite powerful and quiet compared to others of the same size.

Re: New closure allows camping mattress to be inflated in seconds

#90

Post by icebraining »

jjoonathan wrote: post #83
jgrahamc wrote: post #58

The 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.

There are also entirely passive self-inflating mattresses out there. They're filled with (solid-gas) foam that expands when you open the valve. Close the valve and it's ready to go. You store the energy for pumping when you deflate the mattress by rolling it back up. It's much easier to provide energy by sitting on something than by blowing into it :) I don't know the brand name, only that they were old and worn by t…

We have a couple of those, I think we bought them at Decathlon[1] a few years ago. But they're fairly "thin", and not particularly confortable.

My favorite method is still the "foot pump"; some camping matteresses have them integrated, so you just need to open the valve and press down with your foot.

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