Vending machine control circuit

Claim 1

A control circuit for use in an automatic coin-operated vending machine having a plurality of electric vending motors each being operable when energized from a power supply to control an associated commodity vending mechanism, comprising: keyboard means having a plurality of selectively operable selector switches, energization of said keyboard means serving to establish control circuit relationship between each selector switch and an associated vending motor; bistable credit memory means having set and reset control inputs, said memory means being operable to assume credit and non-credit operating states thereof upon individual energization of said set and reset inputs respectively; vending switch means in circuit with the power supply and said memory means and being operable to set the latter into said credit state to precondition a vending cycle; additional switch means in circuit with the power supply and operatively controlled by said memory means, said additional switch means being operable to energize said keyboard means from the power supply in response to said credit operating state and to deenergize said keyboard means in response to said non-credit operating state; plural motor actuated switch means in series circuit with said additional switch means, each said motor actuated switch means being associated with a vending motor and being operable to provide a temporary supply hold circuit thereto in response to energization thereof upon operation of the selector switch associated therewith, each said motor actuated switch means being further operable to deenergize said keyboard means to prevent further operation thereof; first and second motor cam switch means in circuit with the power supply and associated with each vending motor to be operatively responsive to predetermined rotational movement of cam means driven thereby until completion of a vending cycle, said first motor cam switch means being operable to interrupt said temporary supply hold circuit thereto and to substitute therefor a second supply hold circuit from the power supply, and said second motor cam switch means being operable to energize said reset input of said memory means to reset the latter into said non-credit operating state; whereby a vending cycle of each motor controlled vending mechanism is preconditioned upon operation of said vending switch means and independently initiated by a single selector switch operation.