If you stretch a rubber band, it heats up; Keep it that way, for a minute. It cools to ambient temperature. Now release the rubberband. Rubberband becomes very cold. (I invite you all to try it out.)
The toy is just a plastic (thermal insulator) box which somehow uses rubberband. Exact mechanism needs to figured out. Perhaps some hand cranking will be needed.
Mattel/ToysRUS ... are you listening ?-- VJW, Jun 19 2011 The Thermobile http://lasp07c.blog...02/heat-mobile.htmluses a loop of nitinol wire to generate power [xaviergisz, Jul 18 2011] Toy-sized coolers already exist http://koolatrononl...rand-koolatron.htmlThey use a technology developed by NASA, if I recall right. [Vernon, Jul 18 2011] Also http://andythenerd-...bands.blogspot.com/ [MaxwellBuchanan, Jul 18 2011] Baked!... sorta. https://www.youtube...watch?v=lfmrvxB154w [2 fries shy of a happy meal, Jul 24 2017] Excellent (+++)If your bands were contained in a series if small bellows then they could pump cool air into the base of the fridge when tension is released. A valve at the top of the box would let rising warmer air escape.
Excellent.-- 2 fries shy of a happy meal, Jun 19 2011 I think a set of bands might be needed ?..may be 10-30ish...This could be a good home DIY project.-- VJW, Jun 19 2011 Nice idea.
This could work analogously to a real fridge, using a cycle.
Imagine two wheels, over which you stretch a rubber band like this:
(o=========0)
OK, not like that, but that's the best I can do. (The o and the 0 are wheels, the rest is the rubber band). Note that the wheels are two different sizes.
Now, you put a crank on the smaller of the wheels, and you gear that wheel to the bigger wheel, so that they both turn in sync at the same speed.
However, because one wheel is bigger, as the crank (and hence the two wheels) turns, the rubber band is constantly being stretched on one side, and relaxing on the other.
As a result, one side of the band-loop will get cold, the other will get hot. If the loop passes through a small fridge, you could cool the fridge.-- MaxwellBuchanan, Jun 19 2011 That should work; However,
//the rubber band is constantly being stretched on one side, and relaxing on the other.//
How about having a time delay between stretching and relaxing so that rubber band gets time to cool off ?-- VJW, Jun 20 2011 That's why the bellows...<tap-tap> Is this thing on?-- 2 fries shy of a happy meal, Jun 20 2011 //How about having a time delay between stretching and relaxing// Yes, that would help, but is difficult to engineer.
How about using the rollers (either the ones which drive the bands, or additional purely passive rollers) act as heat sinks to unload heat from the stretching bands?-- MaxwellBuchanan, Jun 20 2011 Yeah..That should work. Rollers will be made up of some metal, mostly steel then. If thats not enough, then probably air cooling will have to be used as [21Q] said.-- VJW, Jun 20 2011 You could enclose the rubber band in the hot part of the cycle in a little mini-fridge, to enable it to then absorb more heat.-- hippo, Jun 20 2011 could be a nifty science-fair exhibit: two glasses of water, one gets colder the other hotter.-- FlyingToaster, Jun 20 2011 Unfortunately, modern toy companies would skip all the expensive rubber-band r&d and just rush to market with a product that sprays liquid freon into your child's face the third time they play with it. It would be cheap to manufacture, unrecyclable, a great christmas roll-out, and would come with a product-recall notice already in the box to ward off those pesky class-action suits.-- Alterother, Jul 18 2011 That's a splendid idea. Before long, the things we all enjoyed in childhood -- incandescent lightbulbs, high sulfer coal, chloroflourocarbons -- will go the way of rotary telephones, and our children won't have the chance to enjoy them. Act now! Buy your child an [Alterother] brand toy fridge. Limited Offer! While supplies last!
voidwhereprohibitedbylaw maycauseburnsashpyxia tionorglobalcatastrophe-- mouseposture, Jul 18 2011 Alterorder Inc. has currently suspended sales of all toy refridgerators and related accessories pending the outcome of a class-action lawsuit. We are, however, putting a lot of thought into rubber-band re-development.-- Alterother, Jul 21 2011 //a product that sprays liquid freon into your child's face//
I like this. It answers the question often expressed at picnics: if we can put a man on the moon a quarter million miles from home, why can't we freeze our baby whenever we want?-- ldischler, Jul 21 2011 But we *can't* put a man on the moon. We lost that capability decades ago. In fact, the Americans cannot now even put a man in orbit. The Russians can, so maybe they've got baby-freezing technology as well.
If not, there's always laudanum.-- mouseposture, Jul 21 2011 Actually, back during the Cold War, the Soviets flash-froze thousands of babies, to be thawed out and raised on lightly irradiated grain years after a nuclear exchange, thus ensuring victory at the post-apocalypse Olympics (and yet another chance to inflict their 49-minute national anthem upon the world).-- Alterother, Jul 21 2011 Ha! This guy built a prototype. [link]
It won't cool your beer but the principal works.-- 2 fries shy of a happy meal, Jul 24 2017 " Yeah..That should work. Rollers will be made up of some metal, mostly steel then. "
Mostly steel .... is that like reinforced steel ?-- normzone, Jul 24 2017 random, halfbakery