Digital kitchen scales

[Toneisok]

I recently dropped some digital kitchen scales and they fell apart, to my surprise there is hardly anything inside. As far as i can make out a small printed circuit measures how much an aluminium rod bends. Does any one know how this works?

[woodchopper]

They are callled load cells - they work by resistance varying when a load is put on them - we have them at work - just a lot bigger andmore complicated.

have a look at this - http://www.measurespec.com/tips/principles.htm