"electronically" puncture CO2 cartridge... how?

[Ignoramus13880]

For hobby I'm working on a project that also involves creating a circuit for
activating CO2 cartridge. By activating I mean puncture of cartridge and
fill some stuff with CO2. My first approach was using valves, but because my
circuit needs to be very small and run on butteries I was forced to use
"mini" valves that run on 5V. After some online search all suitable valves I
found can only work with pressure with up to 10 BAR, which (I think) will
not work with CO2 cartridges.



Is there any other method to "electronically" puncture the cartridge using
only elements that run on butteries?

How about a small gearmotor that turns a screw with a puncturing pin
at the end? That should be reasonably cheap and easy to fabricate,
with a few machine tools (lathe, drill press, mill etc).

i

 

[Igor Hudolin]

For hobby I'm working on a project that also involves creating a circuit for
activating CO2 cartridge. By activating I mean puncture of cartridge and
fill some stuff with CO2. My first approach was using valves, but because my
circuit needs to be very small and run on butteries I was forced to use
"mini" valves that run on 5V. After some online search all suitable valves I
found can only work with pressure with up to 10 BAR, which (I think) will
not work with CO2 cartridges.



Is there any other method to "electronically" puncture the cartridge using
only elements that run on butteries?



Thank you.



Regards, Igor

 

[Igor Hudolin]

I was also thinking about this method, but I'm not very excited about it.



Can someone think of some other method to electrically puncture CO2
cartridge?



Thank you



Regards, Igor

 

[Rheilly Phoull]

How about a small gearmotor that turns a screw with a puncturing pin
at the end? That should be reasonably cheap and easy to fabricate,
with a few machine tools (lathe, drill press, mill etc).

i

Just a random thought, mebbe a solenoid to drive the cylinder home into the
nozzle. The cylinders are steel from memory, perhaps the solenoid could be
made large enough to encompass the cylinder ?

 

[Frithiof Andreas Jensen]

Is there any other method to "electronically" puncture the cartridge using
only elements that run on butteries?

A firing pin - the energy to puncture the cartridge is stored in a spring
and released by a low-powered trigger mechanism.

 

[[email protected]]

Can someone think of some other method to electrically puncture CO2
cartridge?

The seal will melt at a lower temperature than the cylinder. Wind some
nichrome wire around the cylinder and power it with a battery. No moving parts
or tricky mechanisms.

Jim

 

[Jim Yanik]

A firing pin - the energy to puncture the cartridge is stored in a
spring and released by a low-powered trigger mechanism.

Or driven by an electric-fired primer.

 

[no_one]

or a 22 caliber blank cartridge

 

[Kryten]

Is there any other method to "electronically"

puncture the cartridge using only elements that run on butteries?

Do you mean puncture the thin metal seal, or the cartridge body(!)?

And how much power have you got to play with?

Perhaps you could have a small motor driving a cogged wheel
attached to a threaded rod with a sharpened end.
The motor turns, and the rod screws into the seal.
Or have the rod push the cartridge onto a sharp point.

The circumference of the wheel divided by the pitch of the thread gives the
mechanical advantage.

K.

 

[Ignoramus32681]

Just a random thought, mebbe a solenoid to drive the cylinder home into the
nozzle. The cylinders are steel from memory, perhaps the solenoid could be
made large enough to encompass the cylinder ?

doubtfully you can do it with a small 5v battery.

i
--

 

[Chris Carlen]

doubtfully you can do it with a small 5v battery.

i

Quite correct, since no 5V battery exists.



--
Good day!

________________________________________
Christopher R. Carlen
Principal Laser&Electronics Technologist
Sandia National Laboratories CA USA
[email protected]
NOTE, delete texts: "RemoveThis" and
"BOGUS" from email address to reply.

 

[Spehro Pefhany]

Quite correct, since no 5V battery exists.

An NiMH 4-cell battery is close enough, no?


Best regards,
Spehro Pefhany

 

[John Fields]

The seal will melt at a lower temperature than the cylinder. Wind some
nichrome wire around the cylinder and power it with a battery. No moving parts
or tricky mechanisms.

 

[Don Foreman]

For hobby I'm working on a project that also involves creating a circuit for
activating CO2 cartridge. By activating I mean puncture of cartridge and
fill some stuff with CO2. My first approach was using valves, but because my
circuit needs to be very small and run on butteries I was forced to use
"mini" valves that run on 5V. After some online search all suitable valves I
found can only work with pressure with up to 10 BAR, which (I think) will
not work with CO2 cartridges.



Is there any other method to "electronically" puncture the cartridge using
only elements that run on butteries?

CO2 cartridges have about 45 to 50 bar of pressure within, depending
on temperature.

Two ways:

1: small DC motor with a centrifugally-actuated snap hammer, like in
an impact wrench. Motor winds up in speed until the hammer pops
loose, hitting a firing pin. This might be a spring-return hammer with
a spring-loaded ball detent that releases the hammer at given speed.

2: Capacitive discharge (SCR or MOSFET) into a solenoid. The small
battery trickle-charges the cap over time, the cap dumps a pulse of
heavy current (10s of amps) into the solenoid at firing time. You
might need a voltage boost circuit (flyback) to charge a
higher-voltage cap so as to use a solenoid of practical coil
resistance.

This might also make good use of momentum -- the solenoid plunger is
accelerated over a distance before striking a firing pin that need
only move a few thousanths to puncture the sparklet. FT = MV

 

[Sjouke Burry]

For hobby I'm working on a project that also involves creating a circuit for
activating CO2 cartridge. By activating I mean puncture of cartridge and
fill some stuff with CO2. My first approach was using valves, but because my
circuit needs to be very small and run on butteries I was forced to use
"mini" valves that run on 5V. After some online search all suitable valves I
found can only work with pressure with up to 10 BAR, which (I think) will
not work with CO2 cartridges.



Is there any other method to "electronically" puncture the cartridge using
only elements that run on butteries?



Thank you.



Regards, Igor

I had an interesting expirience wih a fire system in a tank.
They usd a cartridge to fire open the valve,ignition was
by current pulse. It produced a hell of a mess,all yellow/brown
powder all over the place.

Burry.

 

[Jim Yanik]

I had an interesting expirience wih a fire system in a tank.
They usd a cartridge to fire open the valve,ignition was
by current pulse. It produced a hell of a mess,all yellow/brown
powder all over the place.

Burry.

You can now buy "clean" electric primers from Winchester(IIRC) used in
their Etron-X rifle rounds,but the rifle uses 150V to fire the primer.

(the rifle has a DC-DC boost converter built into it.)

 

[Chris Jones]

If they are like the CO2 cannisters I have seen, then the seal and the body
are both steel, and probably in too good thermal contact to be able to melt
just the seal without heating the whole cannister. In that case it may
explode which is not very nice if you are nearby. I have known kids to
light firelighters underneath these cannisters to blow holes in the side of
metal garbage cans. It would be a hazard to eyesight if nothing else.

Chris

 

[David L. Jones]

For hobby I'm working on a project that also involves creating a circuit for
activating CO2 cartridge. By activating I mean puncture of cartridge and
fill some stuff with CO2. My first approach was using valves, but because my
circuit needs to be very small and run on butteries I was forced to use
"mini" valves that run on 5V. After some online search all suitable valves I
found can only work with pressure with up to 10 BAR, which (I think) will
not work with CO2 cartridges.

Is there any other method to "electronically" puncture the cartridge using
only elements that run on butteries?

On a military sonarbuoy project I worked on we did this by having a
spring loaded spike that was held in place by a string which was rapped
around a resistor body. Pass current through the resistor and it heats
up burns the string and releases the spring loaded spike which
punchures the can.

This mechanism was manufactured in the tens of thousands and proved
100% reliable. It even survived the harsh conditions of being slammed
into the ocesn from a helicopter or plane.

Dave

 

[Rob]

On a military sonarbuoy project I worked on we did this by having a
spring loaded spike that was held in place by a string which was rapped
around a resistor body. Pass current through the resistor and it heats
up burns the string and releases the spring loaded spike which
punchures the can.

This mechanism was manufactured in the tens of thousands and proved
100% reliable. It even survived the harsh conditions of being slammed
into the ocesn from a helicopter or plane.

Dave

Neat! What was it used for - recovery of the units from the ocean floor?

rob

 

[David L. Jones]

Neat! What was it used for - recovery of the units from the ocean floor?

rob

When the unit hit the ocean a salt water battery would activate the
firing mechanism and inflate a bag so that the RF transmitter would
float on the surface while the sonar sensors dangled 100m below on a
tethered cable. The antenna was inside the bag too, so when the bag
inflated the antenna was pulled straight up.
After a set number of hours use the software would burn another
resistor attached to the side of the bag, this would puncture the bag
and cause the buoy to sink to the bottom.
Can't have those Russian fishing trawlers picking up the military
sonarbuoys now can we?
Yep, the ocean is unfortunately littered with tens of thousands of
these things :-(

Dave