Nurri Leva S.A.

It seems to me that the best solution to make levers safe is what LSM did, basically a one-way damper which limits the speed at which the lever can move upwards. This way, whenever pressure is drops quickly in the brew chamber, voluntarily or accidentally, nothing serious happens. I presume LSM has a patent on this idea unfortunately, as implementing it can be done fairly easily using various approaches (yes, this might change the aesthetics slightly and add a few parts, but not that much)

Cuprajake asiest way to check what it does is to choke the lever and press the paddle , any volunteers 🤣

I already answered this in post 111.

Viernes The release paddle was created to end the shot, the possibility to backflush a lever and also vent pressure in case of choking and avoid portafilter sneezing which splashes hot water.

Lever goes back smoothly to the start position.

@Cuprajake

As viernes said, releasing pressure if the machine is choked is precisely one of the reasons why the left paddle solution was invented by nurri.

chlorox I know 🤦😃

Think we’re mixing the conversation, I understand the system, and is use

But I’ve not seen anyone purpose choke a nurri/Vostok and then vent.

As @MediumRoastSteam said we’re looking at the mechanism of the leva returning

As easy you are around the machine doesn’t mean everyone would be, and imagine in a commercial settings where you are mid shot and someone reaches for a cup of the top warmer and hits the paddle, as far fetched as that seems, that’s why they call them accidents.

Any way let’s move one

Can we have some more vids please.

I don’t know how the LSM CLASS system works, but one could imagine a system similar to the dampers on a car. With these, small amplitude movements can happen at fairly high frequencies/fast, but compressing or releasing fully the shocks takes longer due to the dampening effect of oil going through narrow passages and/or valves.

It seems to me that the main danger with spring levers coffee machines is that the lever can swing back very quickly if there is nothing to slow it down, such as a coffee puck. Reducing the maximum release rate would reduce the risk of injuries. I would still make for a messy scene with hot water, coffee grounds or even potentially broken cups in some situations

Eiffel

U r probably right - it may be some kind of hydraulic based system.

I reckon the real need for such a system is in the busy cafe where the baristas may not be as experienced on levers or not fully trained and so the shop owner needs to make sure that a moments inattention does not cost them a damaged jaw and/or broken teeth and his shop a lawsuit! But for the home owner of a spring lever who uses his or her machine every day, I think muscle memory and good work habits should make that highly unlikely. Still, it’s a good reminder for all of us lever users to always be mindful around the uppercut machine! :)

Yeah but it’s good to have the info there for people to see/read for any future buyers

That’s why I do loads of vids because when I was looking for info on the SSP burrs it was a very closed shop, and very little info about them at the time.

tompoland t I am hoping that it can be manually triggered because I like the way the Nurri paddle allows me to choose when to end the shot, like on the Slim Jim.

The Vostock can be manually triggered via the menu selection button beside the display (small steel button). The lever comes up fairly slowly when manually triggered, certainly not fast enough to cause damage. The Nurri would be the same.

The one thing to watch out for…if the lever is pulled down and while the group is filling the pressure release is activated, then the lever will come up extremely rapidly. It would be impossible to do accidentally on the Vostok. On the Nurri it’s unlikely as well, unless something catches in the left hand paddle, or falls and in some way activates it. So care should be taken to keep that area clear.

I would also recommend on the Nurri, if the microswitch activation part goes out of alignment at all, you get it immediately fixed so that this can’t happen due to that.

LMSC

I can only think of the “big stupid brother in law”, most folks have one.
You know the type, laughing at your funny coffee machine and lampooning you making a shot by pulling down on the lever, then letting it go while grinning.
Might be worth it actually.

Amberale

I must be fortunwte because no visitor includijg my brother in law has ever even touched my coffee machine or ever even showed any interest in it back when I owned an izzo despite it being a huge lump of stainless steel on my kitchen counter! :)

LMSC

The effort it takes to pull the lever down may make that of a lower probability than that - it takes someone who really wants to do it in order for it to happen…

chlorox Usually takes about 2 hours on an exhibition day for someone to pull the lever down and then let go, or lock it down then not control it’s rise back….this is on display machines. Stupidity knows no bounds. I may well suggest a locking mechanism on display machines, so the lever can’t be moved.

Or even make a replica rubber lever 😁

DavecUK

Perhaps people behave in a more uninhibited fashion in an exhibition area than those who visit the residence of a friend or relative. Or others have.had less well behaved or more inebriated guests and visitors! :)

chlorox Vostok venting is not via the screen, there is a physical recessed button. I did have a Nurri on the bench for a while.

Yes which is finally why we asked what speed the lever would come back up at 🤣

Got there in the end