To detect an illegal behavior in dispensing of medals from a slot machine.

A dispense time measuring timer 44-2 measures the dispense time with a dispense signal supplied from a management part 48. The measured dispense time is sent to the management part 48 from the timer 44-2. The management part 48 outputs a dispense reference time from a storage 43 and sends it a comparing and judging part 45. The management part 45 calculates the time difference between an inputted dispensary reference time and the measured dispense time. Next, a difference reference time outputted from the storage 43 is compared with the calculated time difference through the management part 48 and the comparison result is sent back to the part 48. When the part 48 confirms that the difference time is longer than the difference reference time, the game is interrupted.