I was a teen when these things came out and I really thought they were on to something with this design.
What they were on to I had no idea, but I sure liked the way it looked
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The mention of linkage right away reminds me of something.
Paper bag manufacturing is a really simple process and even relatively modern machinery is quite simple with a lot of linkages, levers, and cams. I worked in a bag plant for a few years and the machine that makes a lot of the cement bags for the North American market, bags with valves, was from the early 70's and, to me, resembled the game mousetrap more than it did a piece industrial equipment.
So, funny story, I started that job July 2nd, and a few weeks later was the two week summer shutdown. It was all new to me, I'd never seen this equipment before, so I was doing a lot of the smaller, simpler jobs and learning. On the last day of shutdown, the in house expert was installing a rebuilt reject unit on the old machine. It checked through a series of timing, latches, and spring loaded pins, to see if the valve was actually inserted to the bag properly, and if not, it rejected the bag, through a series of latches, levers and linkages. It's a purely mechanical device that I had never seen before.
10 hours into the 12 hour shift, expert guy comes over to me, and asks, would you mind looking at something for me? I've been trying to set it up all day and I can't get it. Maybe a fresh set of eyes will see something. So I go over and see this reject unit for the first time. It was both simple and complicated at the same time, and I had no idea what I was looking at. He explained how it was supposed to work, and I pretended to understand, figuring he'd see that I had no idea and let me get back to installing new belts on the other machine. After about 10 minutes, and trying to further that process I asked, do you have a drawing? Sure, here it is. Right away I notice the cam on the drawing and idiotic me, I think, it looks just like the oddball intake cam profile on a later G13 16V. I ask him what the cam does, he explains it and it actually starts to make sense. So I look back at the reject unit to see if I can put it all together, and the cam guy in me, I notice right away because of that oddball shape. This cam is in backwards. I check. I double check, and I tell him. This cam is in backwards, and show him the drawing. We swap the cam out, he explains how it's supposed to be timed, I make the adjustments, and it works. The next day I get called into my bosses office. Three weeks into my probation, he says congratulations, you've completed your probation early, you start at full rate effective immediately. Pure luck