Sept 25, 2011 - Happy 50th Birthday to... the E-61

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Randy G.
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#1: Post by Randy G. »

On September 25, 1961, fifty years ago, Ernesto Valente filed his US patent #3,230,974, for a brew group under the title "Alternately Seating Valves" which we now know as the "E-61." The original patent can be read and downloaded HERE. Apparently, this group was designed with Faema's first pump-powered machine in mind. Before this, the majority of commercial machines were lever operated. The E-61 incorporated an infusion chamber to soften the initial force of the water delivered by the pump, and from the wording in the patent, it seems that this was an attempt to emulate the way lever machines operated.

I found the patent to be quite interesting in that the group as in use today is quite similar to that original design. Note the use of a plunger with a pin at the top of the group to clear the gicleur which in the contemporary design is protected by a filter screen. One similarity is that the original design had the infusion valve opening at 1.5 BAR, a value still used today.

Anyway, Happy Birthday, E-61. Still making great espresso after 50 years!
EspressoMyEspresso.com - 2000-2023 - a good run, its time is done

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drgary
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#2: Post by drgary »

Hi Randy,

Yes, Happy Birthday E-61! Here's an image from a great restoration thread by Paul Pratt on CG https://www.coffeegeek.com/opinions/cof ... 06-05-2007:



However the popular E-61 was not the first group for a FAEMA pump machine. According to Enrico Maltoni in his book, FAEMA Espresso: 1945 - 2010, in 1959 they introduced the TRR model ("Termo Rimessa Regolata"), designating the TRR's ability to maintain temperature with water, not steam. That machine had boilers for steam and brew water and a pump to increase pressure produced by the boiler that pushed water through a resin water softener. Its groups resemble the later E-61 but look more rounded. There's a photo on page 204 of his book that shows it. He writes that in 1960 the model name was changed to "Tartaruga." Here's a photo* of a similar machine from his collection on tour. It appears to be evolving toward the E-61 design from the photo shown in the book, where there's a shorter extension at the bottom of each group and the top of each group terminates in a nut instead of what appear to be pressure relief valves in this photo. Oddly the group on the right seems to have the familiar E-61 shape. I wonder if it's an early prototype?




His book has pictures but limited text that shows the TRR was preceded by hydraulic groups that did away with lever handles. The 1956 L'autolivellotermica group is shown on President machines. Two other hydraulic groups preceding the E-61 were the 0/4 and 0/2.

Perhaps others viewing this will know more about the innovations being designed into those early non-lever FAEMA groups that anticipated the machine designs we know today.


* Posted by Oscar Peterson and found here on 10/15/11: http://www.kaffee-netz.de/espresso-und- ... tra-i.html
Gary
LMWDP#308

What I WOULD do for a good cup of coffee!