StupidStupidity.co.uk : The Home of Richie G

The USB Toaster

Introduction
OK, hands up, who hasn't thought of a USB toaster? You can get USB-anythings these days, and I'm not just talking about 'proper' stuff like cameras, scanners, printers, drives, and suchlike, I'm talking about things like USB lights, fans, cup warmers, Christmas trees, pencil sharpeners, a shaver (whatever that is...), slippers, foam missile launchers, rechargable batteries, well, the list goes on.

While some of these USB devices are genuinely useful (the foam missile launcher could be fun), there does seem to be a gap in the market for a USB toaster. A Google Search brings up 1.35m results for 'usb toaster' (I don't bother with capitals when I search t'internet), but, and I haven't looked through them all, none of them are actual USB toasters. You can get a box for a USB toaster for $18.99, but no toaster. (I could make that into a phrase - 'It's close, but no toaster'... OK, maybe not...)

So here we go. I am going to try and create a USB toaster. It could well be difficult, maybe even impossible, but nevertheless I shall attempt it.

Diagram No 1 on the right is a rough diagram I drew at work the other night to kind of describe what I am going to do. I also wrote these notes about what this will require:

Knowledge of which parts of a USB lead are power-related
A USB lead that can be used
A Toaster that can be used

Obviously, I will need a bit more than this, but I won't really know until I get there...

25/11/06:
So, let's take a look at what I've got so far:
Picture No 2 A USB lead that can be used
This was relatively simple to find actually. In the radio I work with, we had to use a USB extention lead to attach the webcam to the computer. However, this lead actually had a dodgy end to it, to the effect that it can't be used again. Now, I could do three things to this lead; throw it away (sensible, yet wasteful), attach a new end to it (possible, yet pointless) or attach it to the USB toaster (really pointless, yet what is going to be done).

Knowledge of which parts of a USB lead are for the power
This was quite easy too, given that provided you know what you are looking for, and how to look for it, you can find anything on the Internet. I have also found out the power rating given by a USB lead, and that, in basic theory at least, it should be possible to power a toaster by USB.
Diagram No 3
This is a little diagram with info found here. Any device just taking power from USB would just use pins 1 and 4. Now, my main problem is thus: a toaster runs off 240V AC whilst a USB port runs off 5V DC. Unfortunately, I don't, at the moment, know enough about electronics to find out how to rectify that problem... So, I might have to change over to creating a heating rig and putting a slice of bread between it...

11/01/07:
I got an email from Tom today, the pessimistic git...

A novel idea dude, but with a few small problems (here comes the electronics knowledge, kids!).

It's not very common converting from DC->AC, but it is of course possible. The problem is that there are losses and overheads, which if you read-on, you'll understand that it's not great considering you don't have much to begin with from a USB port.

Anyway, IF you were able to source a DC toaster (maybe something designed for caravans?) then I'd imagine you'd hit the issue of it exceeding the specifications of USB's power delivery.

That is to say, the potential between +V and GND on the USB cable is only 5V DC. I'd imagine any DC toaster made 'for the road', would be either 12 or 24V.

When you also consider that the maximum specified current supply from a single USB port is merely 500mA -- a whole 2.5W doesn't sound great (and it's definitely not enough to run a decent toaster from -- or even those wonderful energy-saving lightbulbs!)

Bugger? Fear not.

http://www.isnichwahr.de/redirect15109.html

The above Japanese fellow decided that he wanted to cook beside his PC, so instead of worrying about AC power. A ~60W peltier was connected to the power of 30 USB ports!

Connected properly you should still theoretically have 5V potential, but have an output wattage of x*2.5W.

So possible .. Albeit extreme.

Banana anyone? ;)

Tom.

I'm not worried though. I had already come to the conclusion that it wouldn't be as simple as converting an existing toaster to USB, and that I would have to make something. However, two slight points to consider would be that firstly, I do not know how to make such a device, and secondly, I am not really that knowledgeable on electronics.

This may take some time...

21/03/08
Doesn't time fly when you're having fun... I can't believe this idea has been on the back shelf for over a year now... I still have the lead, and I still have the idea...

My wasted efforts though are now being put towards turning a defunct iMac into either a goldfish tank or a guitar amp. I'll come back to the toaster...