Wireless Power Transfer

Paul Carpenter wrote:
> On 16 Aug, in article

> The main things you don't say
>
> 1/  Do both sides vibrate synchronously or asynchrously

     Synchronously for the most part

>
> 2/  Is vibration constant due to operation of environment or like
>     driving a car over a pot hole?

Like a car driving over a pot hole... the Vibration is a function of
the  environment this vehicle is in.

> 3/  What temperature range

-20 to +60 C

>
> 4/  Size/volume constraints

Not really... smaller than a bread box.

>
> 5/  Inside or external environment or other special environments like
>     aviation, automotive.

it is to be mounted on a peice of industrial equipment

> There are many ways to transfer or generate power but it depends on the
> environment, becuase if this is constantly vibrating you could even consider
> a 'shaker' genarator and rechargeable battery, like the shaker torches
> that can be got. Similar in energy saving to clockwork radios, wind up
> battery chargers etc..
>

The 140mW doesn't have to be constant... because I was planning on
using this power to trickle charge a battery.

> 140mW (7V @ 20mA) is similar power to a small torch.
>
> Also if any other movements like circular motions could be used to
> generate secondary power.
>
> --
> Paul Carpenter          | paul@pcserviceselectronics.co.uk
> <http://www.pcserviceselectronics.co.uk/>    PC Services
> <http://www.gnuh8.org.uk/>              GNU H8 & mailing list info
> <http://www.badweb.org.uk/>             For those web sites you hate

Eric wrote:
> Have have an interesting problem.
> 
> I need to transfer power (7V @ 20mA approx. 140mW) across a 2-3 inch
> air gap without using a wire.
> 
> It will be in a high vibration and dirty (ie. greasy, oilly)
> evironment.
> 
> Here are my ideas:
> 
> 1) create an air gap transformer
> 
> 2) use super bright LED's and a Solar panel
> 
> Does any one have any experience or knowledge in this area that could
> offer some ideas and literature sources on implementing this.
> 
> Thanks,
> 
> Eric
> 

I think that by the time you get done with some exotic power coupling
system you would be way ahead to use a rechargable battery pack that is
easy to replace.  A typical laptop battery is 4000 mAH or more and 10 to
12 volts.  A battery like this would meet the requirement for a week.
Not nearly as interesting.

Dave Rooney