Hello,
I want to control liquid in a tiny bottle to drop 1 drop of liquid every 1 day.
I searched around and found people using selanoid valve to achieve that.
My problem is the whole project must be so small like a coin
I found some micro selanoid valves that used in medical devices but they are so expensive.
So I thought maybe there is a material of some kind that let liquid pass them when there is a current applied, but I couldn't find.
The closest idea was to use InkJet technology that they use in cartridges to let ink pass, but there is no ready product to buy, and buying cartridges and modified it will cost a lot because I need 7 valves.
Anyone can help me please?
Is there any product or any idea to control drops?
Common lab pipette in a miniature fashion would be subject to tip contamination and evaporation in a 24 hour window, so you must have a closed system.
Depending on the viscosity of the fluid, ultrasonic may prove useful; the on-time would determine the fluid volume "pumped"
neoprene tubing and a small rotating motor are common in liquid medicine dispensing. Converting rotary motion to linear using a solenoid is potentionally a means of monitoring.
I seem to remember many years ago the announcement of a piezo-electric pump - vibration count was proportional to volume.
Considerations:
volume is temperature sensitive
volatile liquids require consideration if atomized
gravity feed verses suction requires some brain-power
Were I going to experiment, I would likely start with miniturizing a piezoelectric fluid pump:
Wow thanks for your answer,
The problem with pezo pump as I saw that it require driving circuit and little high current so that's add up.
It would be great but the buttole is already upside down, so maybe it's better to control the opening instead of pumping it.
The system is open, and the drops should evaporat, it's away of controlling scent in a room.
If I opened the bottle the whole scent will evaporate quickly, also if I made small opening in the bottle the scent will oxidise, so the only way is to keep the bottle closed and only open it to drop the oil.
That thing they have is a precision metering pump my guess it’s from some type of medical device. Unfortunately all there stuff is not listed online. I’ll try and get a picture for you.
It’s has a precision metering body machine in acrylic driven by a stepper motor with an encoder too.
If you look at it you’ll think this had to cost a thousand dollars to make.
If you have a personal physician or know one, or can find one, offer to buy their lunch and let you pick their brain for suggestions about your project. Chances are they can point you to someone or a place of potential sources of information for your project.
One thing to be careful of is what ever you have in the container will or will not wet the surface and many NEVER form a drop.
Pretty damn close
I spend many years on a medical device that used precision pumps like that with acrylic bodies and ceramic pistons, driven by a stepper motor. Build cost was somewhere around $1,200 each.
