## Piezoelectric crystals

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• hi Using piezoelectric crystals i am not getting a continous output of electricity is there any way to convert it into a continous form.Can i control the
Message 1 of 8 , Jun 28, 2005
hi
Using piezoelectric crystals i am not getting a continous output of
electricity is there any way to convert it into a continous form.Can i
control the voltage output and current coming out.I am trying to get
an output of 6 volts and 350 mA.
• pezioelectric crystals put out voltage as a function of the change in pressure. thus, a constant pressure gives nothing. you can get an ac current if you
Message 2 of 8 , Jun 28, 2005
pezioelectric crystals put out voltage as a function of the change in pressure. thus, a constant pressure gives nothing. you can get an ac current if you subject the crystal to high frequency vibration, but you would need several kilos of crystals to get a constant 6v @ 350ma

Ankur Nandwani wrote:
> hi
> Using piezoelectric crystals i am not getting a continous output of
> electricity is there any way to convert it into a continous form.Can i
> control the voltage output and current coming out.I am trying to get
> an output of 6 volts and 350 mA.
>
>
>
>
> Visit the SRS Website at http://www.seattlerobotics.org
>
>
>
>
>
>
>
• ... of ... form.Can i ... There have been some experiments in trying to harness footfall energy into useful power using piezos, but I don t think they are able
Message 3 of 8 , Jun 28, 2005
--- In SeattleRobotics@yahoogroups.com, "Ankur Nandwani"
<ankur2tenn@y...> wrote:
> hi
> Using piezoelectric crystals i am not getting a continous output
of
> electricity is there any way to convert it into a continous
form.Can i
> control the voltage output and current coming out.I am trying to get
> an output of 6 volts and 350 mA.

There have been some experiments in trying to harness footfall
energy into useful power using piezos, but I don't think they
are able to produce much power this way ....

http://www.halfbakery.com/idea/Piezo_20shoes

- dan michaels
www.oricomtech.com
========================
• ... output ... get ... Hi I was planning to use piezoelectric crystals to charge the mobiles by attaching them at the sole of the shoe .If 1cm cube of crystal
Message 4 of 8 , Jun 28, 2005
--- In SeattleRobotics@yahoogroups.com, "dan michaels"
<oric_dan@y...> wrote:
> --- In SeattleRobotics@yahoogroups.com, "Ankur Nandwani"
> <ankur2tenn@y...> wrote:
> > hi
> > Using piezoelectric crystals i am not getting a continous
output
> of
> > electricity is there any way to convert it into a continous
> form.Can i
> > control the voltage output and current coming out.I am trying to
get
> > an output of 6 volts and 350 mA.
>
>
> There have been some experiments in trying to harness footfall
> energy into useful power using piezos, but I don't think they
> are able to produce much power this way ....
>
> http://www.halfbakery.com/idea/Piezo_20shoes
>
>
> - dan michaels
> www.oricomtech.com
> ========================
Hi
I was planning to use piezoelectric crystals to charge the mobiles
by attaching them at the sole of the shoe .If 1cm cube of crystal
can produce 12500v of energy when stress is applied to cant it be
harnessed to get the required output by reducing the voltage output
and incresing the current.
• energy isn t measured in volts. electrical potential is measured in volts, energy is measured in watt-hours or coloumbs, and energy rate of flow is measured in
Message 5 of 8 , Jun 29, 2005
energy isn't measured in volts. electrical potential is measured in volts, energy is measured in watt-hours or coloumbs, and energy rate of flow is measured in watts.

I think you will find that your pezio crystals are giving you 12,500v at about 200uW. you could concievably power a watch from the energy gained from walking, there's just one way to find out

Ankur Nandwani wrote:
> --- In SeattleRobotics@yahoogroups.com, "dan michaels"
> <oric_dan@y...> wrote:
>
>>--- In SeattleRobotics@yahoogroups.com, "Ankur Nandwani"
>><ankur2tenn@y...> wrote:
>>
>>>hi
>>> Using piezoelectric crystals i am not getting a continous
>
> output
>
>>of
>>
>>>electricity is there any way to convert it into a continous
>>
>>form.Can i
>>
>>>control the voltage output and current coming out.I am trying to
>
> get
>
>>>an output of 6 volts and 350 mA.
>>
>>
>>There have been some experiments in trying to harness footfall
>>energy into useful power using piezos, but I don't think they
>>are able to produce much power this way ....
>>
>>http://www.halfbakery.com/idea/Piezo_20shoes
>>
>>
>>- dan michaels
>>www.oricomtech.com
>>========================
>
> Hi
> I was planning to use piezoelectric crystals to charge the mobiles
> by attaching them at the sole of the shoe .If 1cm cube of crystal
> can produce 12500v of energy when stress is applied to cant it be
> harnessed to get the required output by reducing the voltage output
> and incresing the current.
>
>
>
>
> Visit the SRS Website at http://www.seattlerobotics.org
>
>
>
>
>
>
>
• hi ankur, Getting a continous o/p from piezoelectric crystals is not possible coz u need to give a variable pressure (for pressure tansducers)for the o/p. Even
Message 6 of 8 , Jun 29, 2005
hi ankur,

Getting a continous o/p from piezoelectric crystals is not possible coz u need to give a variable pressure (for pressure tansducers)for the o/p. Even then u cannot get o/p in volts it will not exeed the mV level.

Bythe way wat do u study?

Ankur Nandwani <ankur2tenn@...> wrote:
hi
Using piezoelectric crystals i am not getting a continous output of
electricity is there any way to convert it into a continous form.Can i
control the voltage output and current coming out.I am trying to get
an output of 6 volts and 350 mA.

---------------------------------
How much free photo storage do you get? Store your friends n family photos for FREE with Yahoo! Photos.
http://in.photos.yahoo.com

[Non-text portions of this message have been removed]
• pezio crystals are used in electronic lighters, where they supply spikes of a few thousand volts. they are also used in alarm speakers, where resonance can
Message 7 of 8 , Jun 29, 2005
pezio crystals are used in electronic lighters, where they supply spikes of a few thousand volts.

they are also used in alarm speakers, where resonance can generate hundreds of volts across them.

shreyassagar sagar wrote:
> hi ankur,
>
> Getting a continous o/p from piezoelectric crystals is not possible coz u need to give a variable pressure (for pressure tansducers)for the o/p. Even then u cannot get o/p in volts it will not exeed the mV level.
>
> Bythe way wat do u study?
>
> Ankur Nandwani <ankur2tenn@...> wrote:
> hi
> Using piezoelectric crystals i am not getting a continous output of
> electricity is there any way to convert it into a continous form.Can i
> control the voltage output and current coming out.I am trying to get
> an output of 6 volts and 350 mA.
>
>
>
>
> ---------------------------------
> How much free photo storage do you get? Store your friends n family photos for FREE with Yahoo! Photos.
> http://in.photos.yahoo.com
>
> [Non-text portions of this message have been removed]
>
>
>
>
>
> Visit the SRS Website at http://www.seattlerobotics.org
>
>
>
>
>
>
>
• So what you need to do is apply a vibration to one or more crystals, then convert the high voltage low current AC output from the crystals into a lower voltage
Message 8 of 8 , Jul 2, 2005
So what you need to do is apply a vibration to one or more crystals,
then convert the high voltage low current AC output from the
crystals into a lower voltage and higher current AC with step-down
transformers, then convert this to DC with rectifiers which would
then charge a capacitor. To get more power, add more crystals to the
system. To get a more regulated output voltage, add a voltage
regulator, or a DC-to-DC converter.

If all the crystals can be deflected in phase, they can be connected
to the same transformer.

The most efficient way to drive the crystals from a footfall should
be investigated. For example, as the button on an electronic lighter
is pushed, the piezo crystal is slowly deflected one way, then
suddenly released to ring like a tuning fork at its resonant
frequency, or perhaps a spring is slowly compressed, then suddenly
released to strike the crystal. You could do something like that in
the sole of a shoe. It may be hard to do that with more than one
crystal and get them to ring in phase, so you'd be better off with
one big crystal, or a transformer and rectifier for each crystal.

Doug Bell

--- In SeattleRobotics@yahoogroups.com, Triffid Hunter
<triffid_hunter@f...> wrote:
> pezio crystals are used in electronic lighters, where they supply
spikes of a few thousand volts.
>
> they are also used in alarm speakers, where resonance can generate
hundreds of volts across them.
>
> shreyassagar sagar wrote:
> > hi ankur,
> >
> > Getting a continous o/p from piezoelectric crystals is not
possible coz u need to give a variable pressure (for pressure
tansducers)for the o/p. Even then u cannot get o/p in volts it will
not exeed the mV level.
> >
> > Bythe way wat do u study?
> >
> > Ankur Nandwani <ankur2tenn@y...> wrote:
> > hi
> > Using piezoelectric crystals i am not getting a continous output
of
> > electricity is there any way to convert it into a continous
form.Can i
> > control the voltage output and current coming out.I am trying to
get
> > an output of 6 volts and 350 mA.
> >
> >
> >
> >
> > ---------------------------------
> > How much free photo storage do you get? Store your friends n
> > http://in.photos.yahoo.com
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> >
> > Visit the SRS Website at http://www.seattlerobotics.org