Patent US 4,310,885

A point of sale system includes at least one computer, a keyboard, and money receiving, dispensing and storing mechanisms. The keyboard has item keys corresponding to an item for sale, category keys, function keys and a numerical pad. A bill tendered as payment is detected when it enters an opening and, is drawn into a money belt device and to a viewing window. The bill can be accepted or rejected by an operator visually examining the tendered bill. A signal produced by acceptance of the tendered bill is received by the computer to produce change-due data. Each money belt device detects each bill dispensed as change and causes a feedback signal to be produced to dispense another bill as change or to discontinue payment. The money handling mechanisms are placed in a disarmed mode, under control of a computer, at the completion of each sales transaction, and in an armed mode, under control of a computer operated through the keyboard. Another group of keys on the keyboard can produce employee-related data for providing audit information.