h a l f b a k e r yFlaky rehab
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Given MisterQED's valid but world-weary comments on my last idea I propose the following. 1 the laptop power adapter has a very small focussed magnet in it. This is in an area that should it attract an errant staple, it will be a: obvious and b: not matter. 2 the laptop has a small reed switch in the
jack socket. Normally this is open and the socket is in no way connected to the battery. When plugged in, the magnet closes the reed switch and charging can begin. On top of this, the successful connection of the power fires a relay connecting the battery to the jack. So.... there are always 2 layers of safety between the battery (which in the future will contain more and more energy) and a socket short circuit. Once the safety is in place, several jacks can be bunged all over the machine with wild abandon.
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It's typical of this place that your eminently sensible and practical idea gets no attention, isn't it? To me, as a humble herbalist, that seems to make sense. I can't help but wonder about charging by induction. |
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Induction charging may be the future. I've heard of prototype systems in which a table charges a laptop placed on it through induction. |
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But i've never understood why electric toothbrushes have been charged this way for so long but nothing else. What's the obstacle? |
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I think it's efficiency/power. Also, your toothbrush has to fit
quite snugly onto/into the charger, even if there's no
electrical contact, so the advantage isn't huge. |
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I don't get the problem that is being solved by these "2 layers of safety." |
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Shirley we should just wait until fuel cells get safe and
cheap, and then just fill up the laptop with ethanol every
couple of months? |
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Model aero engine driving a miniature generator? |
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Induction charging is totally baked. |
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The reason it's not used all the time is efficiency and the positioning. You are basically taking a transformer, chopping it in half, changing the shape so it's flat, then insulating the two halves from each other with layers of plastic or some such. It's a bit of a pain, and might be a bit much for a fast charge of a high energy density product such as a laptop. |
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In fact there will be even more demand for fast energy transfer in the near future. |
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//just fill up the laptop with ethanol// |
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Methanol might be preferable. There are far better things to do with ethanol. |
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The reason i'd prefer it, at least from this theoretical
position, is that it seems to me that the chargers always
seem to fail at the jack plug end, and having a hole in the
laptop at that point seems to mean that you can't use the
laptop underwater, for example. |
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Maybe you need a cable attached to the laptop, which plugs into a socket in the power brick? |
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Your modifications are an improvement,
but per my last rant, if the staple is
shorting the connection then it will at best
prevent charging. |
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As for other charging methods, either
inductive or capacitive, the key is the trick
used inside computer power supplies,
frequency multiplication. If you up the
frequency and can get the mating pieces
reasonably close together, then losses will
disappear. Considering the reasonably
large area on a laptop, capacitive charging
seems a no-brainer. Just put a x20
frequency multiplier on the incoming
mains power, that will allow you to use a
tiny transformer to drop the voltage down
to 30V, then two matched insulated foil
sheets will make the connection. |
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I've always thought mains AC frequency should go up by quite a lot anyway. I mean I can SEE 50Hz out of the corner of my eye every day. Even 100Hz would mean massive gains in efficiency and falls in annoyingness. |
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