Steam Engines and Tenders.

[tetters]

The loco and tender are connected by multiple draw bars (two or three), which are pinned in place. The pins can, and are, pulled to separate the loco and tender. I believe that the UP Bigboys, had to have their tenders disconnected, to allow the loco to be turned on smaller turntables. The tender was then also turned, and re-connected.
If a coupler was ever used, it would have been a rare practice indeed, and one I have never heard mention of. Diesel auxiliary fuel tanks (modified tank cars) could be interpreted as "tenders", and are coupled.
I suppose you could look at the draw bar, as a link and pin coupler.

Just curious about it. I was thinking about it the other day and tried to look it up on line but couldn't find anything except model train stuff, which just led to further distractions hehehe... must have been asking the wrong question? Thanks for taking the time to answer, much appreciated.