US3848718A

US3848718A - Vending machine control circuit

Info

Publication number: US3848718A
Application number: US00414753A
Authority: US
Inventors: F Bookout
Original assignee: Rock Ola Manufacturing Corp
Current assignee: Rock Ola Manufacturing Corp
Priority date: 1973-11-12
Filing date: 1973-11-12
Publication date: 1974-11-19
Anticipated expiration: 1991-11-19
Also published as: JPS5081197A

Abstract

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. The circuit comprises bistable credit memory means operable in a credit mode thereof to energize selector switches for enabling a single commodity selection. Motor cam switch means associated with each vending motor and controlled thereby are operable to provide a reset signal to the credit memory means to terminate its credit mode after a commodity selection has been made.

Description

[451 Nov. 19, 1974 Primary Examiner-Robert B. Reeves Assistant Examiner-Thomas E. Kocovsky Attorney, Agent, or FirmDavis, McCaleb & Lucas ABSTRACT commodity vending mechanism. The circuit comprises bistable credit memory means operable in a credit mode thereof to energize selector switches for enabling a single commodity selection. Motor cam switch means associated with each vending motor and naming 020 .121 My 9 l 7 s0 MG l l M 9 1 N H 4 9 1 Floyd V. Bookout, Long Grove, Ill.

Assignee: Rock-61a Mann Corporation, Chicago, Ill.

Nov. 12, 1973 Appl. No.: 414,753

Field of Search..........,...

References Cited UNITED STATES PATENTS United States Patent Bookout VENDING MACHINE CONTROL CIRCUIT [75] Inventor:

[22] Filed:

[52] U.S.Cl.

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SHEET 5 OF 5 FIG.5

[IIIllIlllllllllllllllllllllll Ill! VENDING MACHINE CONTROL CIRCUIT BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates in general to automatic coinoperated vending machines, and more particularly to a novel and improved control circuit therefor.

2. Description of the Prior Art Control circuits have heretofore been provided for use in automatic coin-operated vending machines of the type having a plurality of electric vending motors each being operable when energized from a power supply to independently control an associated commodity vending mechanism. One of the main advantages of such a vending machine is that a jammed or disabled condition of one vending motor or its associated vending mechanism will not render the entire vending machine inoperable. A typical control circuit used with such machines comprises a simple credit relay being operable, when energized upon coin deposit of predetermined value, to energize selector switches each for controlling a single commodity selection. The credit mode or operating state of such a credit relay corresponds to its energized condition, the credit relay being inoperable to enable commodity selection when in a deenergized condition. Such a typical control circuit further comprises a plurality of switches each actuated by an associated vending motor to be opened upon energization of the latter, all such switches being connected in series circuit arrangement with the power supply and the credit relay whereby energization of any one of the vending motors serves to interrupt the supply circuit to the credit relay to terminate its credit mode.

However, a problem is presented in using such a series circuit arrangement to deenergize the credit relay, insofar as a jammed or disabled condition of any one of the vending motors which causes its associated motor actuated switch to remain in an open position, will render the entire vending machine inoperable by preventing further energization of the credit relay. To solve this problem, a secondary bypass or feedback circuit is additionally required to isolate the jammed motor circuit and to restore the supply circuit to the credit relay.

Furthermore, with such circuits a temporary interruption of the power supply to the vending machine such as a momentary power failure will terminate the credit mode of an energized credit relay. Power restoration will not reestablish the credit mode without additional coin deposit, so that a power interruption results in a loss of credit.

Need has therefore arisen for a reliable and improved vending machine control circuit which is unaffected by power interruptions and which is simpler in design and therefore less expensive to manufacture than prior known control circuits.

SUMMARY OF THE INVENTION The present invention is directed toward such an improved device, and generally comprises a novel and improved control circuit for use in an automatic coinoperated 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. An example of an improved version of such a vending machine is disclosed in my copending application filed on Nov. 12, 1973 under Ser. No. 414,752 and entitled CAN AND BOTTLE VENDOR.

The present invention includes a bistable credit memory means operable in a credit mode thereof to energize selector switches for enabling a single commodity selection. The bistable credit memory means has set and reset inputs and two modes or operating states thereof, individual energization of each input serving to preset or trigger the memory means into a corresponding one of its operating states. Motor cam switch means associated with each vending motor and controlled thereby are operable to provide a reset signal to the credit memory means to terminate its credit mode after a commodity selection has been made and preferably upon initiation of a vending cycle, the memory means reset input being connected to the power supply by parallel circuits each completed by operative motor cam switch means associated with each vending motor. Should a vending motor controlled by the circuit of the present invention become jammed or disabled, it will be isolated from the power supply by operation of a simple, conventional motor overload protector, deenergization of a motor serving to prevent its associated motor cam switch means from providing a reset signal to the credit memory means.

The bistable credit memory means utilized in the present invention will assume one of its operating states or modes upon energization of a corresponding input and will remain in that operating state until the other one of the inputs is energized, notwithstanding interruption of its power supply. Therefore, once the credit memory means has assumed its credit mode, a momentary power interruption or power failure will not result in a loss of credit, as the credit memory means will remain in its credit mode until it has been reset.

Specifically, the vending machine control circuit according to the present invention comprises: keyboard means having a plurality of selectively operable selector switches, energization of the 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, the memory means being operable to assume credit and non-credit operating states thereof upon individual energization of the set and reset inputs respectively; vending switch means in circuit with the power supply and the memory means and being operable to set the latter into its credit operating state to precondition a vending cycle; additional switch means in circuit with the power supply and operatively controlled by the memory means, the additional switch means being operable to energize the keyboard means from the power supply in response to the credit operating state and to deenergize the keyboard means in response to the non-credit operating state of the memory means; plural motor actuated switch means in series circuit with the additional switch means, each motor actuated switch means being associated with a vending motor and being operable to provide a temporarysupply hold circuit thereto in response to energization thereof upon operation of the selector switch associated therewith, each motor actuated switch means being further operable to deenergize the 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, the first motor cam switch means being operable to interrupt the temporary supply hold circuit and to substitute therefor a second supply hold circuit from the power supply, and said second motor cam switch means being operable to energize the reset input of the memory means to reset the latter into its non-credit operating state. A vending cycle of each motor controlled vending mechanism is preconditioned upon operation of the vending switch means and independently initiated by a single selector switch operation.

It is an important object of this invention to provide an improved control circuit for use in an automatic coin-operated vending machine.

Another important object of this invention is to provide an improved and reliable vending machine control circuit which is simpler in design, less expensive to manufacture and more efficient in operation than prior known vending machine control circuits.

A still further object of this invention is to provide a vending machine control circuit having a credit memory means which is unaffected by power supply interruptions.

Numerous other objects and advantages of the present invention will be apparent from the following description, which, when taken in conjunction with the accompanying drawings, discloses a preferred embodiment thereof.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1-4 are schematic diagramsillustrating the basic features of the preferred embodiment of the present invention, with portions thereof shown in heavy lines to indicate certain electrically actuated circuit elements during operational sequences; and

FIG. 5 is a partial illustration of a typical vending motor suitable for use with the circuit of the present invention and electrical switching means associated therewith DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to the preferred embodiment of the control circuit of the present invention, reference is initially made to FIGS. 1-4. As shown therein, with common reference numerals, the present invention comprises a control circuit for use in an automatic coinoperated vending machine having a plurality of electric vending motors 11, only two of which are shown in the figuresfor simplification, each being operable when energized from a power supply at

power input terminals

12 and 13 to control an associated mechanical commodity vending mechanism (not shown). It will be noted that the vending machine control circuit 10 illustrated in FIGS. 1-4 is adaptable for use with a vending machine having any desirable number of independently actuated vending motors l 1 by making obvious circuit modifications or extensions. The power supply preferably comprises a conventional 120 volt 60 cycle A.C. source. Power input terminal 12 is connected to a power supply line or conductor 14 through a fuse 16 and a door interlock switch 17; similarly, power input terminal 13 is connected to a power supply line 18 through a fuse 19 and a door interlock switch 21.

Power supply lines

14 and 18 supply power to the electric vending motors 11 as controlled by the circuit 10 of the present invention.

The control circuit 10 further comprises a keyboard means having a line 22 and a plurality of selectively momentarily operable commodity selector switches 23 interconnected by a conductor or lead 24. Energization of the keyboard means serves to establish control circuit relationship between each selector switch 23 and its associated vending motor 11 for enabling a commodity selection.

The control circuit 10 comprises a credit magnetic latching relay or other suitable device having a bistable credit memory means and associated electrical switching means operated thereby. The magnetic latching relay means 26 has a set input 27 and a reset input 28, and is operable to assume credit and non-credit operating states or modes thereof upon individual energization of set input 27 and reset input 28, respectively. Instead of the magnetic latching relay means 26, any device having a bistable credit memory means and associated electrical switching means operated thereby could be substituted therefor such as an electronic bistable flip-flop circuit connected to enabling or slave relays; a conventional mechanical stepper having associated switching means; or a combination of two relays, the supply control input of one being connected to the set input and the supply control input of the other being connected to the reset input, a holding circuit for the first relay being controlled by the second relay to be interrupted when the second relay is energized.

The magnetic latching means relay 26 utilized in the preferred embodiment of the present invention is a conventional electromechanical device having a permanent magnet (not shown) adjacently mounted to a solenoid 29, electric current from the power supply being controlled to flow through the solenoid 29 in different directions to produce magnetic fields aiding or opposing the magnetic field of the permanent magnet depending upon which of the

inputs

27 and 28 is energized. The direction of current flow through the solenoid 29 is determined by

semiconductor diodes

31 and 32 respectively connected to the set input 27 and the reset input 28, the cathode of diode 31 and the anode of diode 32 being connected to one terminal of the solenoid 29, the other terminal thereof connected to supply line 18 through conductor or line 33. The resultant magnetic field produced by both the permanent magnet and the solenoid 29 determines the operation of electrical switching means controlled thereby which will be described in detail later.

The control circuit 10 further comprises conventional coin return electromagnet means 34 in circuit with power supply line 18 and coin return electromagnet switch means 36, the latter being included within the magnetic latching relay means 26, the coin return electromagnet means 34 being operable only when energized to actuate mechanical means (not shown) for accepting coin deposit. Deenergization of coin return electromagnet means 34 correspondingly serves to prevent coin acceptance in a well known manner.

In addition, the control circuit 10 comprises known sold-out switch means associated with each vending mechanism, the sold-out switch having first and

second sections

37 and 38 thereof being illustrated in the figures in their normal positions corresponding to fully loaded vending mechanisms, each section being operatively responsive to the presence and absence of items in delivery position in their associated vending mechanism. Each sold-out switch section 37 has one terminal thereof connected to a line 39 in circuit with power supply line 14, each sold-out switch section 37 being operable to energize an interconnecting line 41 in response to the presence of items in delivery position. Each sold-out switch section 38 is also operable in response to the presence of items in delivery position to complete a circuit for energizing a known sold-out solenoid 42 over line 39 and a line 43, the latter being connected to power supply line 18 through a conventional motor overload protector 44. The sold-out solenoid 42 controls mechanical interlock means to precondition actuation of its associated selector switch 23 on the presence of items in delivery position in the vending mechanism association therewith, as described in detail in my US. Pat. No. 3,628,643, issued Dec. 21, 1971, entitled Selector Mechanism for,Coin-Controlled Article Dispensers and assigned to the same assignee as the present invention.

Having described some of the major components of the control circuit of the present invention, its operation and other features will be described with individual reference being made to FIGS. 1-4, which are schematic diagrams illustrating the vending machine control circuit 10 with portions thereof shown in heavy lines to indicate certain electrically actuated circuit elements during separate operational sequences.

SYSTEM AT STANDBY CONDITION FIG. 1 illustratesthe vending machine control circuit 10 at standby condition, the vending machine having items available for delivery to the customer and ready to accept coin deposit. As shown by heavy lines therein, each sold-out solenoid 42 is energized over power supply line 14, line 39, closed sold-out switch section 38, line 43 and power supply line 18, thereby allowing a corresponding selector switch 23 to be closed, as described earlier, for a commodity selection after coin deposit. Each sold-out switch section 37 is operable to energize interconnecting line 41 which in turn is connected to switch means 46, the latter being a part of the'magnetic latching relay 26, which is illustrated in FIG. 1 in its non-credit operating state for the standby condition. The energization of line 41 serves to provide a supply circuit shown in heavy lines to coin return electromagnet means 34 over a conductor 47, a plurality of motor actuated switch means 48 each associated with a vending motor 11 and interconnected by a line 49, line 51, the coin return electromagnet switch means 36 and a conductor 52 connecting the latter to the coin return electromagnet means 34 which, in turn, is connected to the power supply line 18. Switch means 36 is shown in FIG. 1 in its position corresponding to the non-credit operating state of the magnetic latching relay 26. As will be described in more detail later, each motor actuated switch means 48 is operable upon energization of its associated vending motor 11 during a vending cycle to interrupt the supply circuit to the coin return electromagnet means 34 to prevent further coin deposit until completion of a vending cycle.

COIN DEPOSIT FIG. 2 illustrates the circuit conditions upon coin deposit of predetermined value sufficient for a commodity selection. The deposit of such predetermined coins, preconditioned upon the energized condition of the coin return electromagnet means 34 as noted earlier, causes a momentary transfer of a known typical vending switch 53 connected to power supply line 14, the vending switch 53 being operable to energize the set input 27 of the magnetic latching relay 26 to set the latter into its credit operating state to precondition a vending cycle, the vending switch 53 returning to its original position shortly after transfer thereof. The momentary transfer of the vending switch 53 provides an alternating current pulse to the set input 27 as indicatd by the heavy dashed lines in FIG. 2, this pulse being rectified by diode 31 and supplied to the credit memory solenoid 29, thereby causing coin return electromagnet switch means 36 and switch means 46 to transfer to the positions shown in FIG. 2.

This transfer of switch means 36 serves to deenergize the coin return electromagnet means 34 and additionally provides, in conjunction with vending switch 53 (the latter having returned to its original position), a supply to the selector switches 23 shown by heavy lines over a conductor 54 connected to vending switch 53 and switch means 36, conductor 51, each motor actuated switch means 48 and interconnecting line 49, line 47, transferred switch means 46 and line 22. Energization of the keyboard establishes control circuit relationship between each selector switch and an associated vending motor; operation of a selector switch will energize its corresponding electric vending motor 11 in a manner to be described in detail later. Vending switch 53 and the transferred switch 36 together provide means for preventing continuous unauthorized operation of the vending machine should the vending switch 53 jam in its transferred position.

It is seen that switch means 46 is operable to energize the keyboard means from the power supply in response to the credit operating state of the magnetic latching relay means 26 and to deenergize the keyboard means in response to its non-credit operating state. A counter circuit (not shown) could optionally be connected between line 22 and the power supply line 18 for e1ectrical actuation thereof upon coin deposit.

SELECTION MADE FIG. 3 illustrates the circuit conditions upon operation of one of the selector switches 23, control circuit relationship between each selector switch and its associated vending motor 11 having been established upon coin deposit as previously described with respect to the previous operational sequence. Momentarily operating a selector switch 23 serves to energize its associated vending motor 11 as shown by heavy lines in FIG. 3, the power supply being provided over power supply line 14, vending switch 53, conductor 54, transferred coin return electromagnet switch means 36, line 51, each motor actuated switch means 48 and their interconnecting line 49 (transfer of a motor actuated switch 48 not yet having occurred), conductor 47, transferred switch means 46, line 22, one or more non-actuated selector switches 23, lead 24, the momentarily operated selector switch 23, a line 56, non-actuated motor cam switch means 57 (described in detail later),

lines

58 and 59 connected to vending motor 11, motor overload protector 44 and the power supply line 18. It will be noted from the figures that the control circuitry for each vending motor 11 is identical with only the left vending motor 11 shown energized in FIG. 3 for illustration.

Energization of a vending motor 1 1 serves to transfer its associated motor actuated switch means 48 in a known manner, each motor actuated switch preferably being adjacently mounted to its associated vending motor 11 and operatively transferred in response to the magnetic field produced thereby in response to energization thereof until completion of a vending cycle at which time deenergization of the vending motor 11 occurs.

During transfer of motor actuated switch means 48, the keyboard means is deenergized to prevent further operation thereof; as shown in FIG. 3, line 47 (in circuit with switch means 46, line 22 and the selector switches 23) is isolated from the power source carried over line 49 which in turn is connected through closed motor actuated switch means 48, line 51, transferred switch means 36, conductor 54 and vending switch 53 to the power supply line 14. Instead, this supply available at line 49 is connected through now transferred motor actuated switch means 48, a line 61, line 56, motor cam switch means 57 and lines 58 and S9 to provide a temporary supply hold circuit to the operated vending motor 11, as shown by heavy lines in FIG. 3. Transfer of a motor actuated switch 48 therefore prevents energization of the coin return electromagnet means 34 to prevent further coin deposit until completion of a vending cycle.

COMMODITY VENDED AND CREDIT MEMORY MEANS RESET FIG. 4 illustrates the circuit conditions upon vending a commodity and resetting the credit memory means to its non-credit condition. As shown therein, the vending machine control circuit comprises first motor cam switch means 57 and a second motor cam switch means 62, both associated with each vending motor to be operatively responsive to predetermined rotational movement of cam means symbolically illustrated at 63 driven thereby until completion of a vending cycle.

Transfer of the motor cam switch 57 means serves to interrupt the temporary supply hold circuit (shown in FIG. 3) to its associated vending motor 11 and to substitute therefor a second supply hold circuit shown by heavy lines from the power supply line 14, line 39,

lines

58 and 59 connected to the energized vending motor 11 and the motor overload protector 44 in circuit with the power supply line 18.

Transfer of the second motor cam switch means 62 serves to connect the power supply available at line 56 to the reset input 28 of the magnetic latching relay 26 for resetting same into its non-credit operating state, reset input 28 being connected in parallel circuit arrangement with the motor cam switch means 62 associated with each vending motor 11. As shown by heavy lines in FIG. 4, power supply line 14 is connected to the reset input 28 over vending switch 53, line 54, coin return electromagnet switch means 36 (still in its FIG. 3 position), line 51, closed motor actuated switch means 48 and the interconnection'line 49, line 61, line 56 and transferred motor cam switch means 62, thereby causing

switches

36 and 46 to return to their FIG. 1 standby positions; diode 32 rectifies the current flowing through the solenoid 29 to provide a current of proper direction therethrough in order to produce the resultant magnetic field necessary for resetting switch means 36 and 46. The first and second motor cam switch means 57 and 62 are preferably responsive to predetermined rotational movement of the cam means 63 driven by a vending motor 11 prior to commodity release by the vending mechanism associated therewith, so that second motor cam switch means 62 is operable to reset the credit memory means upon initiation of a vending cycle; it is desirable to reset the magnetic latching relay means 26 as soon as possible in order to prevent cheating of the vending machine and to insure that the credit operating state is terminated before any possible jamming or other disablement of a vending motor 11 can occur.

Should a vending motor 11 become jammed or disabled after the magnetic latching relay means 26 has been reset, the motor overload protector 44 will open, thereby interrupting the power supply to the jammed vending motor 11 with the result that its associated motor actuated switch means 48 will return to its FIG. ll standby position, thereby in turn interrupting the power supply circuit to

lines

56 and 61 to terminate energization of reset input 28 through motor cam switch means 62. Should the vending motor 11 remain in its jammed condition, the other vending motors will nevertheless remain operable. Furthermore, the power supply circuit to the sold-out solenoid 42 associated with the jammed vending motor 11 will become deenergized, thereby rendering its associated selector switch 23 inoperable, as described earlier.

Upon return of the coin return electromagnet switch means 36 to its standby position, and upon deenergization of an operating vending motor 11 upon completion of its vending cycle with resultant transfer of its associated motor actuated switch means 48, coin return electromagnet means 34 will be energized to enable further coin deposit to reinitiate another vending selection.

FIG. 5 partially illustrates a typical vending motor 11 suitable for use with the control circuit of the present invention and electrical switching means associated therewith. As shown therein, the vending motor 11 is rigidly attached to a support plate 66, the vending motor 11 being drivingly coupled through gear means to a drive gear 67 for actuating an associated vending mechanism. Attached to the vending motor 11 is its motor actuated switch means 48 having an actuating lever 68 thereof, this lever being operated by a first actuating arm 69 rotatable about a pivot 71 and urged by a spring 72 into a downward position as viewed in FIG. 5. The first actuating lever 69 is operatively engaged by a second actuating arm 73 rotatable about a pivot 74, arm 73 being magnetically attracted to the core of the vending motor 11 by a magnetic field produced in response to energization thereof.

The sold-out

switch having sections

37 and 38 is operated by a pin 76 in turn actuated by a lever (not shown) in response to the presence and absence of items in delivery position in the vending mechanism associated with the vending motor 11.

The motor cam switch means 57 and 62 are actuated by a pin 77 and an actuating lever 78, the latter being rotatable about a pivot 79 in response to predetermined rotational movement of cam means (not shown) driven by the vending motor 11.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it is apparent that various changes may be made in the form, construction and arrangement of its component parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form described being merely a preferred embodiment thereof.

I claim:

1. A control circuit for use in an automatic coinoperated 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 noncredit 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.

2. The invention of claim 1 wherein said memory means and said additional switch means together comprise a magnetic latching relay, said credit and noncredit operating states being determined in accordance with magnetic fields produced thereby.

3. The invention of claim 1 wherein said first and second motor cam switch means are operatively responsive to predetermined rotational movement of cam means driven by each said motor prior to commodity release by the vending mechanism associated therewith; whereby said second motor cam switch means is operable to reset said memory means upon initiation of a vending cycle.

4. The invention of claim 1 and coin return electromagnet means in series circuit with said motor actuated switch means, the latter being in circuit with the power supply and operable to energize said coin return electromagnet means only when none of the vending motors are energized, coin deposit being preconditioned upon energization of said coin return electromagnet means; whereby energization of a vending motor serves to deenergize said coin return electromagnet means to prevent further coin deposit until completion of a vending cycle.

Claims

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.

2. The invention of claim 1 wherein said memory means and said additional switch means together comprise a magnetic latching relay, said credit and non-credit operating states being determined in accordance with magnetic fields produced thereby.