Computerized Shufflers
In 1969, Thomas Segers patented his "electronic card dealer" which was not working with real cards but simulating random selections. Thanks to lights, players could see the result. According to the patent, the design contains multivibrators, logical-and gates and a tube oscillator. The inventor also indicates that transistors could have been used in the circuit. In 1974, David Erickson and Richard Kronmal proposed a shuffler based upon a logic circuit with binary gates. The deck was placed in a holder and cards were extracted one by one, sent into a downward slope channel containing some flaps that would be activated or deactivated, depending upon which stack should be fed. The flap forwarded the card into the proper container and was moved by a coil controlled by the pseudo-random generator. Synchronization was important and several methods were used to ensure that the card would follow the correct path.
Until the 1980s, there were not many innovations. In 1985, Edward Sammsel proposed a machine that extracted the cards from the bottom of two deck holders and put them in a second compartment. Another extractor would eject the card that was taken by the dealer. The order in which the two cards were taken from the holders was driven by a logic circuit whose main parts were a counter and a decoder. Photosensors detected how many cards were present in each compartment and if the card was taken by the dealer. In this case, another card would be processed from the initial holders.
Read more about this topic: Shuffling Machine