I stumbled over a nice drawing, switch dog in German is Schaltnase (switch nose) --- see the JPG (stuff taken from http://www.tecnopinball.org/doc_biblioteca.php schematics "Recel Underwater"). ipdb has the schematics low resolution https://www.ipdb.org/machine.cgi?id=2702 .
The two main places I look for descriptions are pinrepair http://www.pinrepair.com/em/index3.htm#motor and pinwiki http://www.pinwiki.com/wiki/index.php?title=EM_Repair#Gottlieb.C2.AE_Score_Motor - they both do not have such a drawing of " switch dog - switch-dog - switchdog ". Recel uses a lot of Gottlieb technology. Greetings Rolf