The Pythagorean Siphon Inside Your Washing Machine

There's a greedy cup siphon in your washing machine fabric softener try. Also called a Pythagorean cup. It's also used in urinals and novelty drinking receptacles. It's an example of a fluid dynamic mechanism.

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[SteveMould]

This is the first time I've filmed from my toilet! The audio isn't great for that section but I felt the context was important!

[derickito]

I can’t believe that:
1) I watched an entire video about how toilets flush
2) That the youtube algorithm knew it was something I would watch all the way through
What is this world we’re living in?

[Eylrid]

The video in which we learn that toilet siphons are like public schools: Brits and Americans are talking about completely different things.

[TurboSol]

Older American toilets didn't have that mechanism, the flush handle simply pulled a plug at the bottom to release the water into the bowl, this plug floats after you pull it and once the water level reaches the bottom the plug falls back into place stopping the water flow and letting the back of the toilet fill again. Oh also, if you are wondering why the plug doesn't always float and release water, it's because the waters weight is enough to hold it down until you flush.

[DanUpshaw]

This is amazing! This is a very specific problem I have trying to figure out for a long time. I'll often over fill my fabric softener tray and could never stop it draining. Its so awesome that you addressed this one problem that has been perplexing me so much! lol thank you!

[AlenHR]

Cool! I used those on my aquaponics setup many years ago. It is straightforward to make from some PVC piping. When I got it to work, it felt like magic. Really cool system.

[alialghufli]

Recommendation: wanna watch how a washing machine works?
Me: sure why not

[PanicGiraffe]

"Its 3D because we live in a 3D universe"

*LAUGHS IN GLORBROTRONIAN*

[tdya]

This channel is literally the best channel i have ever seen.
This man is a limited edition teacher ☺

[Yashu-ymdx]

Who got this video in recommendation out of nowhere

[matepasztor]

Who else was on the toilet while learning about toilets

[nghiaduy]

What i love most about the channel is the 2D prototype part !!

[Ja_Christopher]

I’ve got a leaky toilet! You’ve just given me the inspiration / confidence to fix it! Thanks!

[alklein]

In the US, the flush mechanism is a flapper valve in the bottom of the tank (made of rubber or a soft plastic material). You pull it up and the rush of water keeps it up until the water flow slows down (there's a very low "collar" around the hole that the valve fits into). When the flow slows, the valve falls down, blocking the hole, and the large valve (the one controlled by the float) fills the tank. (Yes, the water is flowing all the time the flapper valve is open - that fills the bowl.)

[norbikam]

Title is a clickbait, i don't have washing machine

[nathans]

Steve, thanks for the video. This brings to mind the Soxhlet extractor...

[Netsuko]

We usually just have a rubber plug that also floats just enough, but it's also engineered in a way that the pressure of the surrounding water holds it down until you press the handle and pull it up manually, then it floats on top of the water until the cistern has fully drained. It's also open at the top acting as an overflow, so excess water just spills into it, should there be a constant supply of excess water into the tank. Now that I think about it, I am sure we also have these siphon mechanisms here, but only for older systems with a chain to pull on, where the tank is mounted rather high up under the ceiling for some reason.

[hamarana]

Here in Brazil there is just the pipe straight from the water box above .. when you press the button on the wall it releases a strong water current down for as long as you hold it !

[kickinghorse]

Amazing!
I never guessed that I needed to know about a Pythagorian siphon.
Who knew!

[mbcommandnerd]

The toilet in my apartment uses a flapper valve instead of a siphon, which is simply a hinged piece of rubber that is connected to the flush handle by a chain. When you push the handle down, it lifts up the chain, which pulls the valve open. The valve then stays open (as it floats on top of the now rapidly moving water) until the tank has been fully drained, at which point it closes again, and the tank begins to refill. This unfortunately means that you can’t do a half flush, as there’s nothing stopping the water once the valve is open. There are newer toilets which have a push-button system (rather than a handle) for flushing, and those often have two buttons: one for half flushing, and one for full flushing. Not really sure how those work, but there’s a video idea for you! Fun fact: the toilet bowl also contains a siphon, which is why some water always stays in the bowl after the toilet has flushed. The sudden rush of incoming water from the tank starts that siphon, which begins to drain the bowl, and when the water stops coming, the water that didn’t make it out flows back into the bowl. This is also why you can dump a 2-gallon bucket full of water into your toilet to flush it manually if you lose your regular water supply for some reason (it does happen from time to time).