Solved
Yes. That's the cog of a cog loco.
The strange arangement of the cogs were found in Germany by the cog pionieer Nicolaus Riggenbach s apprentice Roman Abt. Abt was a staff member around Riggenbach at his first cog railroad to the mountain top of the swiss mountain Rigi. From Vitznau to top station a cog railroad was build, but the swiss engineer Carl Roman Abt found that Riggenbachs cog wheels quickly climbs up the cogs under heavy loads and looses so it's hold. Also the cog had a typical rattle and thuse a swing movement, which resulted in a characteristical shrugging motion.
So Carl Roman Abt placed two cog rails together, were the cogs overleap eachother, so that allways one cog was in hold, as the others were outgoing and the next one ingoing. That made the motion without the typical shrugging possible and was able to transfer higher loads to the cog rail.
The loco you see here is 97 210 from the austrian Erzbergbahn (iron ore mountain railroad) from Vordernberg to the mine at Eisenerz. The loco transported togehter with a sister engine trains of over 800 tones over the cog ramps at the line.
After her last boiler run she needs a large overhaul in Engine, frame and boiler, so was withdrawn from service and is now used as a display in the museum. Contact with the Railroad Club Eisenerzbahn is established, because 97 210 is the last, which only needs a new boiler overhaul and a light engine overhaul with a frame check to get back in service. All other sister engines missing the cog drive or a in a worse state, which require a very heavy restauration process, which 97 210 does not need.
On the picture you see the cog wheel and at the right and left of the cog wheel the both Belt brakes, which were used as a arresting brake and not for speed decreasing action during the ride.
At the outer left picutre inside the frame you can see one crank of the inside engine, with was a twice coupled steam engine. The outer Engine propelled the adheasion, common wheel drive, the inside engine, also a two cylinder steam engine with a walschaerts driven piston valve gear propelled the two cog wheels.
For braking actions during the trip the engine was fitted with a Riggenbach compression brake, a typical mountain locomotive brake which only can be done at steam locomotives. With the Riggenbach brake the engines were able to stop nearly the complete load in all trip circumstances, especially in the cog rail sections of the line. As on very slow motions or for arresting the train, the belt brake was used, beside the common westinghouse air brake which was only used on emergency or in the flats.
Questions on cog steam locos welcome...
Allways keep two-thrid level in gauge and a well set fire, that's how the engineer likes a fireman
