GB1342175A - Means for producing random time intervals - Google Patents

Abstract

1342175 Random number generators BELLFRUIT MFG CO Ltd 28 April 1972 [30 April 1971] 12325/71 Heading G4D Apparatus for randomly selecting a time interval comprises a low speed clock pulse generator A; a high speed clock pulse generator B; a low capacity counter D, which normally counts continuously the output of clock B; and a switching device C which, to start a time interval, switches the counter to clock A whereby the counter counts from whatever value it has then reached up to a predetermined count when it issues a signal indicating the end of the time interval. A "fruit machine" comprises three wheels R1, R2, R3 each having 20 symbols around its periphery; a motor M which drives all the wheels continuously and three solenoid brakes S1, S2, S3 for stopping the three wheels randomly one after the other. The low speed clock A comprises a 20-position rotary switch driven by the motor M to produce 20 pulses per revolution and the counter D also has 20 states so that any one of 20 time intervals can be selected at random and the wheels R can be stopped at any of their 20 positions. The three solenoids S are energized by a programmer P at the start of each operation of the fruit machine to lift off the three brakes; the programmer P comprises a plurality of cam operated switches driven by a motor. After the cams have rotated through 130, 220 and 280 degrees respectively the cam switches connecting the solenoids S1, S2, S3 to the supply are opened but continue to be energized by holding relays (Fig. 2, not shown). Slightly later in the cam cycle the switching device C starts the time interval and at the end of the interval the counter releases the holding relays, de-energizing the solenoids to apply the brake to the respective wheel R.