Fifteen reels are arranged in five lines and three columns. Plural kinds of symbols are drawn on each reel at a constant pitch, so that one symbol is observed through a display window. There are three type winnings, such as a line winning, which is completed when predetermined symbols are lined on the...http://www.google.co.uk/patents/US20030232643?utm_source=gb-gplus-sharePatent US20030232643 - Symbol display device and game machine
