Kiev 88 shutter

I just bought a partly disassembled Kiev 88 that seems to have some shutter trouble.

The Salyut schematics available elsewhere on this site is very helpful, but I'd like to get a detailed drawing of the "mehanizm vzvoda zatvora" part. I don't understand how the "locking" of one of the cog wheels is supposed to work.

I've looked at the Camera Tech Notes site but there's nothing for the Big Kievs there.