When spray bottles are nearly empty they stop working effectively. You start to get a mixture of liquid and air coming out of the spray head. This is because the suction tube is not fully immersed in the liquid.

This problem can be partially overcome by placing the end of the suction tube in a 'well' at the bottom of the bottle. However, you still need to hold the bottle in one orientation (usually vertically) to ensure the liquid collects in the well.

So I propose making a spray bottle with a device that sucks up the last of the spray bottle regardless of the orientation it is held (ok, not *any* orientation; only up to about 45 degrees from vertical).

The idea is a tubular ring placed at the bottom of the bottle. The tubular ring has several float valves spaced evenly around its top surface. Thus only liquid can enter the tubular ring, and thus only liquid gets sprayed out.

The center of the bottom of the bottle is raised so the the remaining liquids pools above the tubular ring. (see illustration)

any suggestions on a better category are welcome.
-- xaviergisz, May 27 2007

illustrations http://imgur.com/a/LrQPC
[xaviergisz, May 27 2007, last modified Dec 13 2011]

How to make a spray bottle that works in any orientation http://www.youtube....watch?v=ZU6YJ-1AJYU
[xaviergisz, Aug 26 2012]

Would the cost of this be less than the cost of the wasted liquid in a conventional can?

Most aerosols seem to spray their last liquid if you hold them at the right angle - I infer that the "suction tube" is not axial, but has its end in the bottom "corner" of the can; when you tilt the can so that that point is lowest, the last of the liquid can be used.

So, why not just ensure that the suction tube is always oriented the same way in the can, so that the consumer knows that by tilting the can in a certain direction, the last of the product can be gotten?
-- MaxwellBuchanan, May 27 2007


Yep, cost of production would be higher than normal, but it might be selling feature in a re-usable spray bottle.

Good idea about indicating the orientation to hold the bottle to expel the last of the liquid. However this is still a bit awkward.

There are two advantages of my invention: no required orientation and prevents spraying of air/liquid mixture.
-- xaviergisz, May 27 2007


How about having the dip-tube be fairly flexible and weighted, so that it always dips into the lowest point on the can?
-- MaxwellBuchanan, May 28 2007


I'm surprised that pump sprayers don't have the liquid contained in an inner liner like disposable baby bottles.
You'd get no air mixing in with the liquid. There would be no need for a stem, and it could be used at any orientation.
-- 2 fries shy of a happy meal, May 28 2007


great idea [2 fries]. My idea is clearly an over-engineered solution.
-- xaviergisz, May 28 2007


I think the float valves will close when there is still liquid in the tube, but the air, under pressure, would not be allowed to enter the tube...so it would stop spraying. But it would improve the scavenging a little.

[2 fries]'s idea is do-able, but it would need to be solvent resistant. It might be good for mixing by shaking, too, as with paint cans, because the flexible membrane would erm... flex and dislodge the sedimentation.

I find that gently shaking the can, when it is spraying air/liquid, sometimes helps to get everything out. I wonder if this effect could be utilised somehow?

Finally, since most spray cans have a conical top, then I wonder if they could be used upside down without the suction tube.
-- Ling, May 29 2007


//So, why not just ensure that the suction tube is always oriented the same way in the can, so that the consumer knows that by tilting the can in a certain direction, the last of the product can be gotten?//

On many spray paint cans (others as well) you'll find a mark that the nozzle should point toward. The mark denotes the direction of the pick-up tube. Tilting the can to spray at a moderate downward angle toward the mark puts the pick-up tube at the can's lowest point. (So if you have to spray upwards, turn the nozzle away from the mark.)

//Finally, since most spray cans have a conical top, then I wonder if they could be used upside down without the suction tube//

Yes. Some spray paint cans - particularly those for ground marking for utilities, construction, etc. - are meant to be used inverted. They do not have a pick-up tube.
-- lurch, May 29 2007


In my model airplane flying days, we had "stunt-tanks" for fuel where the pickup tube was flexible and had a weighted end. It always followed the liquid no matter which angle the tank was placed.
-- AusCan531, Aug 27 2012


I've found that gently rocking the can back and fourth near vertical achieved a complete discharge of the contents before the propellent was discharged. Finally I have observed that there are quite nice refillable containers that use a bladder and a pressurized reserve to achieve complete even aerosol discharge with no propellent at all.
-- WcW, Aug 27 2012


Maybe what you need is a weight on the end of the pickup tube; google on 'clunk tank' and see what you find; these are used for aerobatic model airplanes so they can get the last vestige of fuel from a tank regardless of orientation of tank.
-- Steamboat, Aug 30 2012



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