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Why does a spray bottle work?

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Re: Why does a spray bottle work?

#101

Post by chewxy »

MichaelApproved wrote: post #41
vanilla-almond wrote: post #28

A few years ago, a British inventor appeared on a TV show called Dragon's Den (UK version of Shark Tank) and pitched his idea of an improved spray bottle called the Anyway Spray. Instead of a normal plastic tube inside a bottle with an opening at the end, he designed a tube with millions of tiny perforations along its length. This meant the spray bottle could operate at any angle (even upside down) and could empty al…

Why isn't this in everything? I'd easily pay an extra few cents to have this in spray bottles. It's such a frustrating problem.

Here's a cheaper and faster hack: soft tube + weighted end.

The weighted end will tend to go towards where the liquids are. Imagine a bottle being held lengthwise. The weighted end will be in the same location as where the liquid is.

Turn the bottle upside down... the weighted end drops to where the top of the bottle is, along with where the water is.

Standard pressure thingies still work - you still get a spray. No need for custom membranse.

Re: Why does a spray bottle work?

#102

Post by Declanomous »

hexane360 wrote: post #57
jetrink wrote: post #27

Earlier quoted context omitted.

MONIAC [1] was an analog computer designed in 1949 that used water to model the national economy of the United Kingdom. 1. https://en.wikipedia.org/wiki/MONIAC

This was brilliantly parodied in Terry Pratchett's Making Money .

I got a Kindle for Christmas, and I've been reading through Discworld chronologically. I'm on Raising Steam right now, and I already feel like I'm going to have to reread the series with a list of references open. There were a lot of places where it was apparent there was a reference to something, but it was completely inaccessible as an American in his late 20's.

At the same time, I almost feel like I shouldn't read the last book for a while, it's going to be really bittersweet.

Re: Why does a spray bottle work?

#103

Post by kazinator »

hanniabu wrote: post #99
kazinator wrote: post #86

Earlier quoted context omitted.

If it was simply perforations, it wouldn't work when the bottle is upright because those perforations would let the air into the top of the straw. Rather, the straw is made of a membrane which lets water through while blocking gas.

You need to let air through or else it creates a vacuum. What's happening is it just slows the flow of air enough to be able to get suction from the fluid. Having fluid in the tube also helps.

You need to let air through into the bottle to replace the volume of ejected water. No air should ideally be entering the straw.

Re: Why does a spray bottle work?

#104

Post by PhasmaFelis »

chewxy wrote: post #101
MichaelApproved wrote: post #41

Earlier quoted context omitted.

Why isn't this in everything? I'd easily pay an extra few cents to have this in spray bottles. It's such a frustrating problem.

Here's a cheaper and faster hack: soft tube + weighted end. The weighted end will tend to go towards where the liquids are. Imagine a bottle being held lengthwise. The weighted end will be in the same location as where the liquid is. Turn the bottle upside down... the weighted end drops to where the top of the bottle is, along with where the water is. Standard pressure thingies still work - you still get a spray. No…

I saw an instructional thing about that. They did it with a bit of silicone tubing the same diameter as the original, and a steel nut with matching inside diameter. Swap out the tube and screw the nut over the end.

I'm not sure you could actually make it work upside-down without crimping, but at any normal usage angle it works great.

Re: Why does a spray bottle work?

#105

Post by fencepost »

chewxy wrote: post #101
MichaelApproved wrote: post #41

Earlier quoted context omitted.

Why isn't this in everything? I'd easily pay an extra few cents to have this in spray bottles. It's such a frustrating problem.

Here's a cheaper and faster hack: soft tube + weighted end. The weighted end will tend to go towards where the liquids are. Imagine a bottle being held lengthwise. The weighted end will be in the same location as where the liquid is. Turn the bottle upside down... the weighted end drops to where the top of the bottle is, along with where the water is. Standard pressure thingies still work - you still get a spray. No…

What it really comes down to is the question of the actual goal and the costs of reaching that goal. For a huge percentage of things "good enough" is in fact good enough. It's also important to not confuse the goal and proposed solutions for reaching that goal.

For the example above, is the goal to be able to spray upside down? To ensure that the sprayer is able to spray a higher percentage of what's in the bottle? How large is that percentage improvement (90% up to 95%?), what's the incremental cost of increasing that percentage, and what is the actual worth of 5% of the contents of the bottle?

A draw tube that is flexible enough to fold in half, strong enough to not kink, sturdy enough to not collapse when bursts of suction are applied, weighted enough to stay in liquid, strong enough to assemble quickly and easily, etc. is probably also expensive enough to just not be an economical solution.

By the way, if you don't purchase cleaning supplies regularly you may have missed that a lot of those tubes have gone away - they're now molded as part of the bottle so just tipping the bottle will put all remaining liquid at the intake point.

Re: Why does a spray bottle work?

#106

Post by GordonS »

thomk wrote: post #85
vanilla-almond wrote: post #28

A few years ago, a British inventor appeared on a TV show called Dragon's Den (UK version of Shark Tank) and pitched his idea of an improved spray bottle called the Anyway Spray. Instead of a normal plastic tube inside a bottle with an opening at the end, he designed a tube with millions of tiny perforations along its length. This meant the spray bottle could operate at any angle (even upside down) and could empty al…

That episode of Dragons Den is infuriating. Here is a guy who has invented something with a widespread, common appeal. He invented a product that potentially fixes a real problem in 1,000,000,000 units per year and he has to give away 20% of his invention to get support.

The investors on Dragon's Den always want too much equity - I would imagine that anyone going on the show would know that.

I also think some people go on the show knowing that they're not going to get investment at a sensible equity level, and are really on there as a way of marketing their idea to a wider audience.

Re: Why does a spray bottle work?

#107

Post by esrauch »

ggg9990 wrote: post #93
ebikelaw wrote: post #92

Earlier quoted context omitted.

I have a spray bottle that I bought to clean windows, because it can shoot a stream about 20 meters which is great. It is also labeled "sprays upside-down!" which is really misleading. I thought it sprayed in any orientation but it doesn't. It only sprays when held straight up or straight down. There's an inlet on the base of the handle for the inverted case, and a valve that prevents the main pickup from drawing in…

That’s not “really misleading,” it’s “barely misleading” or perhaps “slightly misleading.”

I think most people would assume the marketing meant "can spray at any angle, even the hardest case of upside down".

I knew I did when reading this thread until I saw this comment.

Re: Why does a spray bottle work?

#108

Post by lucb1e »

Stratoscope wrote: post #65
alanbernstein wrote: post #32

Earlier quoted context omitted.

That's funny, I don't know what that diagram is trying to convey.

Your confusion is understandable, since the Wikipedia article doesn't even make the slightest attempt to explain the diagram. So let me try. Let's start with the piston pump on the left. The brown piece moves up or down in a tube, and the two black "T" figures are valves that open or close in response to water pressure. The down arrow next to the piston indicates that the piston is currently moving down and pushing o…

> Your confusion is understandable, since the Wikipedia article doesn't even make the slightest attempt to explain the diagram.

A little meta, but in these situations I usually try to improve the source and post a reply saying I edited it, instead of explaining it to one (or a few) person(s) here. Not saying it was bad that you just wrote a big comment explaining it completely! Just an idea of equal effort while reaching more people :)

Re: Why does a spray bottle work?

#109

Post by annabellish »

acjohnson55 wrote: post #98
thomk wrote: post #85

Earlier quoted context omitted.

That episode of Dragons Den is infuriating. Here is a guy who has invented something with a widespread, common appeal. He invented a product that potentially fixes a real problem in 1,000,000,000 units per year and he has to give away 20% of his invention to get support.

He had the option to reject the deal, no? It's a free market for venture capital, so if that deal is so bad and the opportunity is so good, he should have been able to find a better one. From my perspective, having a great idea is not enough. Even having a proof of concept is not enough. There's a lot more that goes into building a successful business. Investors have to price in the chances of all the things that can…

>Likewise, as a founder, you often need at least some investors that can help propel you forward in some way.

Which is the infuriating part, when the "investors" contribute nothing to the project but a tiny slice of money they didn't work for to begin with, and get vastly disproportional returns for it.

Re: Why does a spray bottle work?

#110

Post by exikyut »

chewxy wrote: post #101
MichaelApproved wrote: post #41

Earlier quoted context omitted.

Why isn't this in everything? I'd easily pay an extra few cents to have this in spray bottles. It's such a frustrating problem.

Here's a cheaper and faster hack: soft tube + weighted end. The weighted end will tend to go towards where the liquids are. Imagine a bottle being held lengthwise. The weighted end will be in the same location as where the liquid is. Turn the bottle upside down... the weighted end drops to where the top of the bottle is, along with where the water is. Standard pressure thingies still work - you still get a spray. No…

What cheap alternatives to small bits of metal could be used for the weight?

Metal could interact with and damage a lot of different things.

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