1. Field of the Invention
The present invention relates to a slot machine which drives step motors to start and stop rotating reels, and more particularly to a slot machine capable of making an appeal to the player at having won a prize.
2. Background Art
In a conventional slot machine, a plurality of reels, for example, three to five reels are disposed in a horizontal row. These reels have various symbols arranged in different sequences around their peripheral surfaces. The reels are respectively coupled to drive shafts of step motors. After one or a couple of coins ( or tokens ) are inserted, the step motors start driving all the reels at the same time in response to an operation of a start lever. The step motors are individually stopped in response to stop signals. The stop signals are automatically and randomly generated in an auto-stop type slot machine, or are generated upon manual operation of at least a stop button in a manual-stop type slot machine. When the reels are stopped in this way, three symbols are displayed in each of display windows which are provided for the respective reels. Thus, as for three-reel type slot machine, nine symbols in total are displayed as a result of each game.
Ordinarily, in three-reel type slot machines, five, i.e. three horizontal and two diagonal winning lines are provided across the display windows such that three symbols appear on each winning line when the reels stop. Depending upon the number of tokens (or coins) inserted for a game, one or more of these winning lines are effectuated for the game: the more tokens make the more lines effective. If three symbols aligned in any of the effective winning lines constitute one of predetermined winning symbol combinations, a number of tokens are paid out according to the rank of prize assigned to the consequent winning symbol combination.
There are many prize ranks in slot machines. For example, when a given symbol, e.g. "Cherry" stops on the effective winning line, a couple of token are paid out as a prize of the lowest rank called a small hit. A middle hit is given when predetermined two or three kinds of symbols are aligned in the effective winning line, with payment of about five to fifteen tokens. In addition to these prize ranks, a big hit is provided as a prize of the highest rank. As an example of big hit, a jack pot is given when a symbol combination "7"- "7"- "7" is displayed in the effective winning line, awarding an enormous number of tokens. Another example of big hit, called bonus hit, allows the player to play a special or bonus game again at an especially high probability of winning. Accordingly, most players feel a great interest in the big hit.
To make the player feel greater satisfaction at having won the big hit in the interest of greater amusement for the player, many conventional slot machines are designed to show a special performance when the big hit is carried off. To get stronger appeal to the players, a variety of such triumphal performances have been developed. For example, in those slot machine which have luminescent elements on one or opposite ends of the winning lines to indicate the effective winning line or lines by lighting, all the luminescent elements start winking or lighting in different colors at the big hit.
Slot machines are also known which have lamps or the like mounted inside the reels to illuminate the reels in a winking fashion when the big hit is carried off.
Since the luminescent elements can have few winking patterns, the above-described known triumphal performance is too monotonous to have an appeal to the players. Using a lot of luminescent elements having different colors may give variety to the performance, but cannot sufficiently relieve the monotony. Rather, the increased number of luminescent elements and diffusion plates therefor as well as complicated wiring of these elements must raise the cost of the slot machine.
Indeed the slot machine having lamps inside the reels can make an attractive triumphal performances by designing colors and light-up patterns of the lamps appropriately. But this resolution also needs to incorporate the lamps and their drive circuit into the slot machine, so that not only the cost of the slot machine is raised, but also the scale of the slot machine must be increased to provide a room for the lamps.
Recently, a matrix-type slot machine has been suggested in U.S. patent Application Ser. No. 08/184,033 filed by the present applicant, which has a plurality of, e.g. nine reels arranged in a matrix. Because the nine-reel type slot machine has a lot of winning lines, i.e. three horizontal, three vertical and two diagonal winning lines, some inexperienced player may not easily recognize on which winning line the big hit combination appears, or what kind of hit or winning symbol combination is provided.