I'm not bashing your thread, and you asked why it isn't in use. Stop and think about what that article is suggesting. It's talking about uninterupted power flow from the engine to the wheels through two shafts. This is done 'wet clutches' 'Phasing in' and 'phasing out' each gear. It states that there are complicated electronic and hydraulic controls for this transmission. The 'phasing' of gears on these clutches is fancy speak for saying that the clutches are being slipped in a soft shift, the same as is done in a lazy shifting automatic transmission. It's not that a transmission like that couldn't be fitted to a farm tractor. It's that it's not a practical thing to do, in my opinion for a farm tractor. The reason that the Select-O-Speed (and perhaps some of it's counterparts of that time) didn't work is that it had poor manual controls that resulted in a poor shifting, jerky transmission. It didn't get coined the Jerk-A-Matic for nothing. It earned it. The eliptical gearing of those transmissions was actually pretty reliable. It was the controls that were poor. That's why manual controls don't work well in most cases. The modern power shifts mostly use a complicated mass of speed sensors and modulator valves to control the shifts. Their timing and pressure is that critical that they must be recalibrated in service to compensate for wear over time. It's my belief that it's nearly impossible to get that kind of timing from a manual control system, in a way that is repeatable so as not to destroy the transmission. Think what you like, but planetary transmissions are what's out there today. If this technology had any merit in an ag application, I find it hard to believe that someone would not have done it by now because it could be somewhat more efficient.
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Today's Featured Article - The Fordson F Ignition System - by Anthony West. A fellow restorer contacted me earlier this year asking for some help and advice on a model F that he was restoring. He had over a period of months spent a fair amount of his hard earned cash on replacement parts for the old "trembler" ignition. Sadly though all his efforts seemed to be a waste of time and money as he still couldn''t get the temperamental old thing to run correctly!! If i said that this was a little frustrating for him that would be "conservative" in fact the problem had reduce
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