Optical vend-sensing system for control of vending machine

• US 20070084872A1
• Filed: 12/15/2006
• Published: 04/19/2007
• Est. Priority Date: 04/29/1998
• Status: Active Grant

• Current Assignee: Automated Merchandising Systems Incorporated (Seaga Manufacturing Incorporated)
• Original Assignee: Automated Merchandising Systems Incorporated (Seaga Manufacturing Incorporated)
• Inventors: Spentzos, Kyriakos, Hair, James
• Granted Patent: US 7,343,220 B2
• Time in Patent Office: Days
• US Class Current: 221/21
• CPC Class Codes: G07F 11/04 in which magazines the articles are stored one vertically above the other
• CPC Class Codes: G07F 11/42 the articles being delivered by motor-driven means
• CPC Class Codes: G07F 9/02 Devices for alarm or indication, e.g. when empty; Advertising arrangements in coin-freed apparatus alarms or warning devices indicating the interruption of flow to be metered G07F15/10
• CPC Class Codes: G07F 9/026 for alarm, monitoring and auditing in vending machines or means for indication, e.g. when empty

Abstract

For ensuring that a vending machine motor will continue to operate until a product has descended through a vending space or an established time interval has elapsed, an optical beam is established across the vend space through which a product must drop. A change in beam intensity is detected. By preference infra red light is emitted at one focal point of an elliptical reflector, and detected at the other focal point. The light is emitted in pulses in the preferred embodiment, and the optical sensing system has automated calibration and error detecting functions.

Claims

1. A vending machine, comprising:

a transparent front,

a dispensing mechanism configured to perform vending operations and dispense a product upon selection by a consumer,

a vend space comprising a portion of space in said vending machine through which said selected product will freely fall, independent of a product lowering elevator, into a bin portion for retrieval by the consumer, and

an optical vend-sensing system configured to sense when said selected product freely falls through said vend space,

said optical vend-sensing system comprising;

an emitter mechanism configured to generate electromagnetic radiation that substantially spans said vend space,

a detector mechanism configured to receive electromagnetic radiation generated by said emitter mechanism and to detect changes in said electromagnetic radiation caused by said selected product as it freely falls through said vend space, the emitter mechanism and the detector mechanism being positioned above a customer accessible portion of the retrieval bin portion, and

a calibration circuit for calibrating the optical vend-sensing system based on ambient light entering the vending machine through the transparent front.

2. The vending machine of claim 1, wherein the calibration circuit calibrates the emitter mechanism based on ambient light entering the vending machine through the transparent front.

3. The vending machine of claim 1, wherein the calibration circuit calibrates the detector mechanism based on ambient light entering the vending machine through the transparent front.

4. The vending machine of claim 1, wherein the electromagnetic radiation generated by the emitter mechanism is pulsed at a frequency selected to reduce interference from ambient light.

5. A vending machine, comprising:

a transparent front,

a dispensing mechanism configured to dispense a product upon selection by a consumer,

a vend space comprising a portion of space in said vending machine through which said selected product will freely fall, independent of a product lowing mechanism, into a bin portion for retrieval by the consumer, and

an optical vend-sensing system configured to sense when said selected product freely falls through said vend space,

said optical vend-sensing system comprising;

an emitter mechanism configured to generate electromagnetic radiation that substantially spans said vend space;

a detector mechanism configured to receive at least a portion of said electromagnetic radiation generated by said emitter mechanism and to detect changes in said electromagnetic radiation caused by said selected product freely falling through said vend space;

a control mechanism configured to control said dispensing as a function of when said optical vend-sensing system senses said product freely falling through said vend space; and

a calibration circuit for calibrating the optical vend-sensing system based on ambient light entering the vending machine through the transparent front.

6. The vending machine of claim 5, wherein the calibration circuit calibrates the emitter mechanism based on ambient light entering the vending machine through the transparent front.

7. The vending machine of claim 5, wherein the calibration circuit calibrates the detector mechanism based on ambient light entering the vending machine through the transparent front.

8. The vending machine of claim 5, wherein the electromagnetic radiation generated by the emitter mechanism is pulsed at a frequency selected to reduce interference from ambient light.

9. A vending machine, comprising:

a transparent front;

a product storage and display area;

a dispensing mechanism configured to perform vending operations in order to dispense a product selected by a consumer from said product storage and display area to a product delivery path, said product delivery path including a vend space defined by said transparent front and by said product storage and display area, and defining a portion of the space in said vending machine through which said selected product will freely fall, independent of a product lowering or guiding mechanism, into a bin portion for retrieval by the consumer; and

an optical vend-sensing system configured to sense said selected product as if freely falls through said product delivery path, said optical vend-sensing system comprising;

at least one emitter mechanism configured to generate electromagnetic radiation that substantially spans a cross-section of said product delivery path, said cross-section having a front-to-rear depth approximately equal to a front-to-rear depth of said vend-space, and

two or more active detector mechanisms configured to receive electromagnetic radiation generated by said at least one emitter mechanism and to detect changes in said, electromagnetic radiation caused by passage of said selected product;

wherein the electromagnetic radiation generated by the at least one emitter mechanism is pulsed at a frequency selected to reduce interference from ambient light.

10. The vending machine of claim 9, further including control circuitry operatively coupled to said two or more active detector mechanisms and configured to provide a signal indicating that said selected product has passed through said vend space.

11. The vending machine of claim 10, fiber including a machine control unit communicating with said control circuitry and said dispensing mechanism, said machine control unit configured to control said vending operations of said dispensing mechanism.

12. The vending machine of claim 11 wherein in response to receiving said signal from said control circuitry indicating that said selected product has freely fallen through said vend space, said machine control unit communicates with said dispensing mechanism to conclude said vending operations.

13. A vending machine, comprising:

a transparent front;

a dispensing mechanism configured to perform vending operations in order to dispense a product selected by a consumer;

a vend space comprising a portion of the space in said vending machine through which said selected product will freely fall, independent of a product lowering mechanism, into a bin portion for retrieval by the consumer; and

an optical vend-sensing system configured to sense when said selected product passes through a substantially unconstrained portion of said vend space, said optical vend-sensing system including,

a plurality of emitters configured to generate electromagnetic radiation that spans nearly all of a fixed cross-section of said vend space and

a plurality of detectors configured to receive said electromagnetic radiation generated by said emitter mechanism and to detect changes in said electromagnetic radiation caused by said selected product passing through said vend space;

wherein said emitters modulate the electromagnetic radiation generated at a frequency selected to avoid interference caused by ambient light entering said vend space through said transparent front and said plurality of detectors are constructed to detect changes in electromagnetic radiation emitted at said modulation frequency.

14. The vending machine of claim 13, wherein the electromagnetic radiation is modulated at a frequency higher than 120 Hz.

15. The vending machine of claim 13, wherein the electromagnetic radiation is modulated at a frequency of 2 KHz.

16. The vending machine of claim 14, wherein said electromagnetic radiation is generated by a row of said emitters, said row substantially extending a front-to-rear depth of said substantially unconstrained portion of said vend space.

17. The vending machine of claim 16, said vending machine further includes a machine control unit operationally connected to said dispensing mechanism and a control circuit operationally connected with said machine control unit and said optical vend-sensing system, wherein said machine control unit causes said dispensing mechanism to continue said vending operations until a signal from said control circuit has been received indicating a positive vend detection has occurred or in response to a predetermined secondary condition when said positive vend signal from said control circuitry has not been received by said machine control unit.

18. The vending machine of claim 17, wherein said vending machine initiate a corrective action when no positive vend signal from said control circuitry has been received by said machine control unit and said predetermined secondary condition has been reached.

19. The vending machine of claim 18, wherein said corrective action comprises maintaining a credit established by said customer to allow an alternative selection or to provide a refund.

20. The vending machine of claim 19, wherein said plurality of emitters create at least one plane of said electromagnetic radiation substantially spanning, laterally and depthwise, an area at or above an opening of said bin portion but below a lowest said dispensing mechanism such that said selected product entering said bin portion must pass through said plane.

21. A vending machine, comprising:

a transparent front;

a dispensing mechanism comprised of a plurality of dispensing units, the dispensing mechanism configured to store and dispense a product selected by a consumer;

a customer-accessible retrieval bin;

an optical vend-sensing system including an emitter device configured to emit electromagnetic radiation through a vend space to a detector device; and

an anti-tamper processing circuit configured to receive a signal indicative of the output of the detector device, and configured to determine whether the optical vend-sensing system has been tampered with in an attempt to defraud the vending machine;

wherein the optical vend-sensing system is located below the dispensing mechanism and above the customer-accessible retrieval bin, and wherein the optical vend-sensing system is configured to detect that the selected product has been dispensed to the retrieval bin when the detector device senses a temporary reduction in the amount of electromagnetic radiation received from the emitter device due to the product falling through the vend space.

22. The vending machine of claim 21, wherein the anti-tamper processing circuit determines that the optical vend-sensing system has been tampered with based on the amount of electromagnetic radiation received by the detector device that attempts to flood the optical vend-sensing system.

23. The vending machine of claim 22, wherein the emitter device is comprised of a row of emitters located on one side of the vend space, the row of emitters extending in a depth-wise direction from the front of the vending machine toward the back of the machine.

24. A vending method for determining whether a product is delivered in a transparent front vending machine, the method comprising:

sending a delivery signal to a product delivery system based on a customer ordering event;

advancing a product to be vended from an area where it is displayed to a vend space located behind said transparent front of the vending machine and in front of the product display area and extending to a product retrieval bin;

monitoring a substantially unconstrained cross-sectional area of said vend space through which the product being vended freely falls with a monitoring system located to detect when the product falls through said unconstrained vend spaces the monitoring system using one at least two light emitters and a plurality of light detectors in which light emitted by each of said at least two light emitters is detected by at least two of said plurality of light detectors whenever each of said at least two emitters is active; and

determining if said product to be vended was delivered to said product retrieval bin based interruption of light emitted by each of said emitters reaching said at least two light detectors.

25. The method of claim 24, wherein each of said at least two light emitters is constructed to emit light at a modulation frequency selected to avoid interference caused by ambient light entering said vend space through said transparent front and said plurality of said light detectors is tuned to the modulation frequency selected.

26. The method of claim 25, wherein said plurality of light detectors detect changes in said electromagnetic radiation caused by said selected product passing through said vend space by determining that said electromagnetic radiation received by plurality of light detectors has been temporarily reduced by a predetermined threshold amount.

27. The method of claim 26, wherein said predetermined threshold amount is determined by taking into account ambient electromagnetic sources.

28. A method of controlling a transparent front vending machine, the method comprising:

providing a product storage area within the vending machine what a product to be vended is displayed;

providing a product delivery path within the vending machine, the product delivery path being the area between the transparent front and the product storage area and extending in substantially unreduced cross-section to a customer accessible product delivery bin;

providing a vending mechanism which moves the product to be vended from the product storage area into the product delivery path;

creating a light detection plane across the substantially unreduced cross-section of said product delivery path above said customer accessible product delivery bin by pulsing one or more light emitters on one side of said product delivery path at a preselected frequency and using one or more light detectors provided on an opposite side wall of said product delivery path to monitor interruption of said pulsed light;

wherein said frequency is selected to minimize interference from an ambient light source.