Re: OT: Nitrogen filled tires

John Larkin <jjlarkin@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
news:rqhdh3ppempbl753o1irpf2f6b32vj50ub@xxxxxxx:

On Thu, 18 Oct 2007 01:13:03 GMT, Rich Grise <rich@xxxxxxxxxxx> wrote:

On Wed, 17 Oct 2007 17:18:33 -0700, John Larkin wrote:
On 17 Oct 2007 23:52:40 GMT, Jim Yanik <jyanik@xxxxxxxxx> wrote:
John Larkin <jjlarkin@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in

But pumps fill tires, and alarms don't.

And a small pump would work pretty much continuously.

Not really;normally,tires don't lose that much pressure daily.

Then there's the problem of getting/keeping the correct tire
pressure under varying tire temperatures.If your auto-pump
continuously pumps,you could over-pressure your tires(when they heat
up) and they would wear too fast,particularly in the center of the
tread.

It would have a regulator, of course.

Oh, dear, I see a snag. To temperature-compensate the regulator, you'd
have to measure the temperature _inside_ the tire.

Thanks,
Rich


Why temperature compensate the regulator? Just keep the tires at
constant pressure; pump or bleed as appropriate.

John



You can bleed off pressure a lot easier (and quicker)than raise
it,especially with your proposed system.(your device would bleed a hot
tire,and then when the vehicle gets parked for a half hour,the pressure is
too low,and your device does not pump when the vehicle is at rest.it also
will take a long time to raise pressure.)

one more thing to fail and possibly cause a tire to fail when you least
need it to fail.
suppose your regulator fails and rapidly bleeds all(or just too much)of the
air out of a tire(at 70MPH)? some vehicles have catastrophic tire failure
when that happens,some have rollover crashes.
Some just lose control.

--
Jim Yanik
jyanik
at
kua.net
.

Relevant Pages

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