Tire sensors (was: Proc Pwr and Northstar Coolant Loss)

[Gordon Couger]

On Wed, 24 May 1995, Dave Williams wrote:

>
> -> Pardon my ignorance, but, how do these sensors relay the information
> -> back to the main unit?  Wireless/RF transmission?  Slip Rings (I
> -> doubt it)?
>
>  Low power RF.  If you drive past another Corvette with a flat tire,
> your own warning will go off.
>
>
:  Sorry, but I had to ask...  how does the (rotating) transmitter get
:it's power?  One slip ring and the chassy for ground?  Or some sort of
:generator (like the old self-winding watches)?
:-Steven Ciciora

I can see several ways to power it. Recified RF charging a real good
and real large capacitor. Or build a very poor generator in the wheel
with the magnets part of the nonrotating brake housing. It might be
possible to pickup enough electrical noise to charge a Capacator and
run the transmiter when the air pressure falls or when querried. Resulting
in a awful lot of charge time and a very small transmit time.

The saying is a lot eaiser than the doing. 

Gordon
Gordon Couger - 624 Cheyenne, Stillwater, OK 74075
gcouger at master.ceat.okstate.edu 405-624-2855 evenings 
    I do not speak for my employer