| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a game machine enabled to cope with reliable counter-measures against a fraudulent act by detecting more reliably the fraudulent act against detection means for detecting a game medium.SOLUTION: Game balls having entered a first startup winning port 13a, a second startup winning port 13b and a big winning port 13c are individually detected by two sensors (proximity switches 14a, 15a and 23 and photo sensors 14b, 15b and 23a) of different detection systems, and an abnormal winning is decided when the difference between the detected ball number by the proximity switches 14a, 15a and 23a and the detected ball number by the photo sensors 14b, 15b and 23a exceeds a predetermined threshold value. The threshold value is a value more than the difference between the detected ball number of the proximity switches and the detected ball number of the photo sensors at the time when a ball jamming in first winning passages 1360a and 1360b corresponding to such one of the plural winning ports as has the longest flow-down distance from the proximity switches to the photo sensors, thereby to prevent abnormal winning decision due to a ball jamming.</p> |
