another_jim wrote:Thanks for posting these pics; I'll link to them in the bench review.
If I'm not mistaken, I can see why they didn't patent their paddle group, it looks a lot like the prototype E61 with needle valve.
Feel free to use them as you wish.There are some other interesting variations in the Bianca flavour of E61, so I'll add a few more photos and notes later.
That Valente patent app. is a fine thing, if you are a coffee aficionado! However, as you've pointed out he was a proper steampunk engineer. That valve on top of the E61 group would never work as drawn, as a per se flow/pressure metering device for shot control purposes. He doubtless had such a device or similar in place on his test rigs, to calibrate the gicleur sizings, or assess rate changes, etc.
In my engineering R&D experience, company patent lawyers would insist that you include all possible variations in patent submissions, often delaying development by months while we had to check and rewrite far-fetched variations for the application. Why? Shuts down the opposition of course, but if claim is too wide it's less likely to be accepted. So stick every possible variation in the drawings but don't necessarily elaborate in the text.
Meanwhile, for people who are thinking of obtaining some Bianca metering valve parts and adding them to their proprietary E61, I'd say don't go there - it's a carefully engineered system that is unlike the other E61's I've seen in several internal respects. Don't be misled just because E61 castings and raw shaping emerge from only a couple of places. Proprietary machining, tolerancing and design detail are important and hard to replicate without facilities.
Jake_G has a better approach mapped out for understanding the modifications needed to add pressure/flow control to an existing machine, along his Long and Rambling Path and Tonefish is moving an E61 add-on development, elsewhere on H.B.