I don't speak German, but I think you are asking for an excavator model. If not, please ignore this post. Here is one that I just did this afternoon. Took 4 hours, and has not been optimized. Feel free to use it, just don't be selling it. There is no skin, and it is not animated.
I made it as close to the one that you provided as I could. Hope it's useful to you. It is a little on the hi-poly side, around 3700 polys, but it could be cleaned up quite a bit. The treads are crap, the first version I did had individually modeled tracks and was over 5500 polys. Seemed like a huge waste. Anyway, enjoy!
Excavator2 Cheers!
Mark