Electronic Cigarette Smoking Machine Controller Needed

[Chris Havel]

Just a stupid question since I have no interest in e-cigs.

They basically just have a power switch? I suppose you decouple or want to de-couple the power from the draw? i.e. Make them separate.

e.g.
1) Force the switch closed (i.e. tape) and apply power some other way.
2) Modify the e-cig, so the power switch is used.

The e-cig vents when the solenoid is off and goes to your apparatus when engaged.

There should be no reason to substitute anything but a constant voltage power supply for the e-cig supply?

==

FWIW: Then there are these controllers: **broken link removed**

I'm not sure I get what you're saying. E-Cigarettes are almost always used with batteries. Some of the batteries can be quite sophisticated with variable voltage and power selection as well as puff counters. While my machine which can and does work with Ego type batteries I prefer to use a constant voltage power supply so I can be sure about how much power is being supplied to the coil. Decoupling applying power from the draw is what I've seen ecigarette users do. So I want to be able to mimic it with the machine.

The universe of e-cigarettes is vast and a testament to capitalism and Chinese manufacturing capabilities. See Madvapes.com and MyFreedomSmokes.com to get an idea of the number and types of vaporizers, batteries and liquids on the market.

 

[Dr_Doggy]

my ecig battery is li-ion i believe, based on the usb charge adapter, it has over current protection as well as a shutoff timer so you can not run it over 15 seconds by accident, mine personally is 3v with 1ohm coil,

the coil screws on the top which holds the juice as well.

 

[Chris Havel]

my ecig battery is li-ion i believe, based on the usb charge adapter, it has over current protection as well as a shutoff timer so you can not run it over 15 seconds by accident, mine personally is 3v with 1ohm coil,
View attachment 92448 View attachment 92450 View attachment 92449
the coil screws on the top which holds the juice as well.

We have quite a few of the 510 batteries and tank model clearomizers models. I believe the standard rechargeable batter is 3.7 volts. The coils range from sub Ohm to 2 ohms or so. Is yours a top or bottom coil?

 

[ronv]

We have quite a few of the 510 batteries and tank model clearomizers models. I believe the standard rechargeable batter is 3.7 volts. The coils range from sub Ohm to 2 ohms or so. Is yours a top or bottom coil?

I'm a little confused. We only have 2 circuits. One to turn on the coil and one to turn on the puff valve. What does the relay do?

 

[Chris Havel]

I'm a little confused. We only have 2 circuits. One to turn on the coil and one to turn on the puff valve. What does the relay do?

The relay is what switches the power from the power supply to the coil. The relay receives the same 4-second 15 volt pulse that opens the 3 way valve to apply vacuum to the e-cigarette. The PS is wired through the relay. When the solenoid in the relay receives the 4 second pulse it closes the circuit allowing the controlled power from the PS to flow to the coil.

Watch the movie. You can see that there is 0 amps and 4 volts on the PS readout until the relay closes the circuit. Then the Amp reading goes up to around 2 amps for a total of about 8 watts of power delivered to the e-cig coil. In the movie you will see that there is air bubbling through the 3 gas traps all the time. When the valve switches the air is draw through the ecig atomizer and you see the vapor in bottles.

We want to control the valve and the relay separately. Here is a program where we preheat the coil for 1 second prior to applying suction to the atomizer for 3 seconds. 3 puff cycles.

Time 0 sec 15 volts to the relay, relay closes circuit and sends whatever power that is set to the coil in the ecig atomizer.
Time 1 sec 15 volts to the 3-way valve. Valve switches the vacuum to the ecig atomizer
Time 4 sec 15 volts off to both relay and valve. Power off to coil and valve switches vacuum away from the atomizer.
Time 30 Repeat.
Time 60 Repeat
Time 65 Stop

 

[ronv]

Chris Havel
That clears it up. Now I understand a lot better.
The relay is an extra part. We could turn on the coil directly from the box instead of having the box turn on the relay that turns on the coil.... I think. But either way will work. I'll make it big enough to work directly from the box and you can decide.
I was wondering why the bubbles didn't stop - now I know - the line gets purged.
I also understand your thoughts on frequency of the whole cycle. There is a time when everything is off and the end of each cycle. I should probably add this, right? And it should also be adjustable or just a fixed period of time like 25 seconds??

 

[Chris Havel]

Chris Havel
That clears it up. Now I understand a lot better.
The relay is an extra part. We could turn on the coil directly from the box instead of having the box turn on the relay that turns on the coil.... I think. But either way will work. I'll make it big enough to work directly from the box and you can decide.
I was wondering why the bubbles didn't stop - now I know - the line gets purged.
I also understand your thoughts on frequency of the whole cycle. There is a time when everything is off and the end of each cycle. I should probably add this, right? And it should also be adjustable or just a fixed period of time like 25 seconds??

I started out with a solenoid button pusher that slips over the battery and pushes the button on the battery just like a person would. The battery was a black box. There was no way to know how much power and voltage was being delivered. That's why I came up with the power supply. I substituted the relay for the battery button pusher which "pushes the button" on the power supply to allow for 4 second heating during the 4 second puff. The power supply accurately delivers any constant voltage I want at a given amperage depending on the resistance of the coil. Now I know all the variables in Ohm's law. As I said earlier, the biggest driver in e-liquid vaporization and delivery to the subject is the voltage. The amount of e-liquid delivered can increase 3X (100->300 mg) by increasing the voltage from 3.7 to 5 volts. Also, more dangerous aldehydes are generated at higher voltages and temperatures.

The vacuum pump is set for around 1.2 liters per minute. A 4-second puff is then 80 mL. When the flow is not directed through the e-cigarette atomizer it is pulling room air from the other port on the 3-way valve. So the vacuum pump is pulling room air for the other 26 seconds in a 30 second puff interval program.

As to the programs:

Coil 0-3 seconds valve 0-3 seconds
Coil 0-4 seconds, valve 0-4 seconds
Coil 0-4 seconds, Valve 1-4 seconds for a 1 second preheat 3 second puff
Coil 0-5 seconds, valve 1-5 seconds, 1 second preheat 4 second puff
Coil 0-5 seconds, valve 2-5 seconds, 2 second preheat and 3 second puff
Coil 0-6 seconds, valve 2-6 seconds, 2 second preheat 4 second puff
Coil 0-6 seconds, valve 1-6 seconds, 1 second preheat and 5 second puff
Coil 0-6 seconds Valve 0-6 second
Coil 0-8 seconds, valve 0-8 seconds

Much more difficult to have the 2 timers going. It gets complicated. I wouldn't even know where to begin on how to do it. I guess cycling it with 30 seconds between puffs so you would end up adding 8 seconds for the longest puff duration the next puff would 0-8, 38-46 , 76-84 ....N seconds.

Then maybe a 60 second cycle time 0-8, 68-76 , 136-144 , .....N

2 cycle times is enough.

 

[ronv]

Ok, almost got it done I think, but let me try it out on you.
- on off switch. turns on the 15 volts to the box.
- reset start switch. stops a cycle if it is running and starts from zero.
- delay this turns on the coil and after the time set on the knob turns on the valve. It delays the start of a puff from the time the coil is turned on from 0 to 1.8 seconds in increments of .2 seconds.
-puff time sets the time the valve is on based on the setting of a knob. The time can be set from 1 to 10 seconds based on the setting.
-rest time. this time is added to the end of the puff time based on the setting of a knob. It can be set for 1, 2, 4, 8, 16, 32, 64, 128, or 256 seconds.
-cycle count counts the number of complete cycles based on a setting of a knob. Can be set for 1, 2, 4, 8, 16. 32, or 64 cycles. The machine will stop after the count is reached and needs another reset and start to begin a new set of cycles.
So here is an example:
Delay = .2
Puff = 2
Rest = 8
Cycles= 8
Time for 1 cycle: .2+2+8 = 10.2 seconds.
Time from start to finish: 10.2 X 8 = 81.6 seconds. 8 puffs. of 2 seconds each starting .2 seconds after the coil is first turned on. Total coil on time 17.6 seconds (2.2 seconds per puff). Total puff time 16 seconds. Total rest time 64 seconds.
I envision a LED for power on, coil on, puff on and resting on so you will have a visual indication of where it's at in the cycle.
Don't be shy. If there is something else you want or need now is the time to bring it up.
Chris Havel

 

[Chris Havel]

So I can set the controller to have a 1.8 second delay, a 4 second puff time and 16 seconds between puff for 1.8 + 4 + 16 = 21.8 second cycle time. I can then run this program for 1, 2, 4, 8, 16. 32, or 64 cycles. 16 cycles would take 16*21.8 = 348.8 seconds
I could have a program that would have a delay of 1.6 seconds a 4 second puff time and a rest time of 32 for 37.6 second cycle time. 16 puffs would take 10 minutes.

That would work. Probably wouldn't run to many of the very short rest time settings though. One question why are the setting geometric progressions while the puff time is linear?

I'll bounce this off my colleague and see what he says.

Thanks Ron.

 

[ronv]

So I can set the controller to have a 1.8 second delay, a 4 second puff time and 16 seconds between puff for 1.8 + 4 + 16 = 21.8 second cycle time. I can then run this program for 1, 2, 4, 8, 16. 32, or 64 cycles. 16 cycles would take 16*21.8 = 348.8 seconds
I could have a program that would have a delay of 1.6 seconds a 4 second puff time and a rest time of 32 for 37.6 second cycle time. 16 puffs would take 10 minutes.

Yes, that is correct.

That would work. Probably wouldn't run to many of the very short rest time settings though.

Easy to take a low one or two out. I thought it might come in handy for quick tests just to see if the setup was ok or something like that.

One question why are the setting geometric progressions while the puff time is linear?

Three reasons actually.
The delay and puff times are fairly short so I wanted them to be pretty accurate and 10 steps could span the values you wanted.
The rest and count times have a wide range, for example count from 3 to 60. With only a ten position switch I could only get 3 to 30.
The other is that counters often count that way so I used numbers that were easy to decode since the counters count 1, 2, 4, 8, 16 etc.

I'll bounce this off my colleague and see what he says.

Sounds good.

[/QUOTE]

 

[Chris Havel]

Sounds like it's building time. Any idea how much the parts are?

 

[MCU88]

Sounds like it's building time. Any idea how much the parts are?

Tayda Electronics www.taydaelectronics.com are very, very good. The price is right. The quality is good. Their turn around time is fast. Their error rate is low.

Highly recommend

 

[Chris Havel]

Tayda Electronics www.taydaelectronics.com are very, very good. The price is right. The quality is good. Their turn around time is fast. Their error rate is low.

Highly recommend

You know the best vendors. The prices look low. If the price is less than $60 I can order the parts and probably get reimbursed off of our grant. You of course would have to put it together. While I love electronics and like tinkering with computers and mass spectrometers there is no way that I could assemble the thing. I think the most important thing is that I test it and incorporate it into the paper that I'm writing. I would like to move quickly because I can publish with the controller that I now have. If I got yours, I would test it against the 4 second no delay one and say that it is a big improvement because of the coil preheating more closely mimics the actual e-cigarette user. I can't say for sure, but if we say in the paper that the controller was obtained from your "company" you might be able to sell a few copies.

One question: It sure is appreciated, but why are you interested in helping us out?

Chris

 

[MCU88]

One question: It sure is appreciated, but why are you interested in helping us out?

Too much time on my hands. The dream of making a dollar. Genuine passion for engineering 'bringing something to life'

I am good at making vegetable soup too. My doctor says it is so juicy and full of flavor. Now that is coming from an DOCTOR!

 

[Chris Havel]

Too much time on my hands. The dream of making a dollar. Genuine passion for engineering 'bringing something to life'

I am good at making vegetable soup too. My doctor says it is so juicy and full of flavor. Now that is coming from an DOCTOR!

I am getting close to retirement age but I'm having too much fun at work. It is satisfying when something goes from an idea to an actual device that works and does what it's supposed to do.

Can you put together a parts list?

 

[MCU88]

Can you put together a parts list?

Give me an absolute tangible requirements and analysis document and I'll do the whole thing using an PIC microcontroller with C firmware.

I'll design it. I'll document it. I'll build it. I'll mail it to you. Just pay me for the parts and postage.

What country are you in? I am in Australia...

 

[Chris Havel]

Give me an absolute tangible requirements and analysis document and I'll do the whole thing using an PIC microcontroller with C firmware.

I'll design it. I'll document it. I'll build it. I'll mail it to you. Just pay me for the parts and postage.

What country are you in? I am in Australia...

I'll see if I can put together a document detailing what we've been discussing. tangible requirements being the timing specifications and voltage requirements? I'm not sure what you mean by an analysis document though.

I'm in San Francisco California.

 

[Chris Havel]

ronv and MCU88. Sorry I got confused as to who I was responding to in the last few posts. If both of you want to build controllers that's great.

 

[ronv]

ronv and MCU88. Sorry I got confused as to who I was responding to in the last few posts. If both of you want to build controllers that's great.

Hi Chris,
No problem.
I'm not quite done with the design schematic, but a rough price for the printed circuit boards alone are a little over $100 for 5. Just a guess that there would be a little less than $100 for each set of parts. Most of that in switches, the box, knob etc. The electronics are pretty cheap. I enjoy the design, but not so much the PCB layout and assembly so I classify that as work. But based on what you paid for the one you have I think I would still do it for 25% less than your guy. In any case I'll finish the schematic and you can see what they want for it and we can go from there.
MCU88 has an unbeatable deal if he is up for it. It would be a good fit for a micro.

 

[MCU88]

I'm not sure what you mean by an analysis document though.

In academia we call it an requirements and analysis document. It is the first step, the initiation of an project. Your analysis (could be just conclusions with or without support) -- I am more of an practical person though. The less reading the better. I like to see block diagrams and requirements in dot point / step form. So just two page me an document. Say a paragraph on the project goal and an down to earth explanation about what it is meant to do. Then the requirements in high detail step form. Block diagram(s) Paragraph on any conclusions / errata that you may wish to add. You may wish to consider restraints also. Such as the max or min size of the project enclosure.

Make up your mind with everything. No abstract please.