Optical vend-sensing system for control of vending machine

• US 7,343,220 B2
• Filed: 12/15/2006
• Issued: 03/11/2008
• Est. Priority Date: 04/29/1998
• Status: Expired due to Fees

• Current Assignee: Automated Merchandising Systems Incorporated (Seaga Manufacturing Incorporated)
• Original Assignee: Automated Merchandising Systems Incorporated (Seaga Manufacturing Incorporated)
• Inventors: Hair, James M. III, Spentzos, Kyriakos P.
• Primary Examiner(s): Crawford; Gene O
• Assistant Examiner(s): Waggoner; Timothy
• Application Number:
  US11/639,231
• Publication Number:
  US 20070084872A1
• Time in Patent Office: 452 Days
• Field of Search: 700/236, 221/7, 221/2, 221/13
• US Class Current: 700/236
• 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 as in claim 1 further comprising:

a reflector mechanism constructed and adapted to direct at least some of the electromagnetic radiation generated by the emitter mechanism towards said detector mechanism.

6. 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.

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

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

9. The vending machine of claim 6, wherein the electromagnetic radiation generated by the emitter mechanism is pulsed at a frequency selected to reduce interference from ambient light.

36. A vending machine as in claim 6 wherein said optical vend-sensing system further comprises:

a reflector mechanism constructed and adapted to direct at least some of the electromagnetic radiation generated by the emitter mechanism towards said detector mechanism.

10. 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 it 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.

11. A vending machine as in claim 10 further comprising:

a reflector mechanism constructed and adapted to direct at least some of the electromagnetic radiation generated by the at least one emitter mechanism towards said two or more active detector mechanisms.

12. The vending machine of claim 10, 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.

13. The vending machine of claim 12, further 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.

14. The vending machine of claim 13 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.

15. A vending machine as in claim 10 wherein at least some of the ambient light enters the vending machine through the transparent front.

16. 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 emitters 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.

17. The vending machine of claim 16, wherein the electromagnetic radiation is modulated at a frequency higher than 120 Hz.

18. The vending machine of claim 16, wherein the electromagnetic radiation is modulated at a frequency of 2 KHz.

19. The vending machine of claim 17, 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.

20. The vending machine of claim 19, 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.

21. The vending machine of claim 20, wherein said vending machine initiates 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.

22. The vending machine of claim 21, wherein said corrective action comprises maintaining a credit established by said customer to allow an alternative selection or to provide a refund.

23. The vending machine of claim 22, 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.

24. A vending machine as in claim 16 wherein, in operation, said plurality of emitters are concurrently operative.

25. A vending machine as in claim 19 wherein, in operation, the emitters in the row of emitters are concurrently operative.

26. A vending machine as in claim 23 wherein, in operation, said plurality of emitters are concurrently operative.

27. A vending machine as in claim 16 further comprising:

at least one reflector constructed and adapted to direct at least some of the electromagnetic radiation generated by the emitters towards said detectors.

28. 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 space, the monitoring system using 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 on interruption of light emitted by each of said emitters reaching said at least two light detectors.

29. The method of claim 28, 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.

30. The method of claim 29, 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.

31. The method of claim 30, wherein said predetermined threshold amount is determined by taking into account ambient electromagnetic sources.

32. A method as in claim 28 wherein all of said at least two light emitters are concurrently operative.

33. A method as in claim 28 wherein light emitted by said at least two light emitters is directed to at least some of said plurality of light detectors by a reflector.

34. 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.

35. A method as in claim 34 wherein the ambient light source is external the vending machine and wherein the interference enters the vending machine though the transparent front.

37. A method as in claim 34 wherein pulsed light from said light emitters is directed to at least some of said one or more light detectors by a reflector.