Slot machine display reels are provided with a plurality of symbols occupying differing proportions of the circumference of the reel, such that those symbols which require greater prominance occupy a larger proportion of the circumference. Associated with each reel is a spinning mechanism which is able...http://www.google.fr/patents/US4790537?utm_source=gb-gplus-shareBrevet US4790537 - Multi-size reel symbols
