Abstract:
An optical vend sensing system for use in vending machines employs a row of light emitters on one side of a region through which a vend product passes during delivery and a row of light detectors on the opposite side. Each detector is substantially aligned with a corresponding one of the emitters, and is capable of receiving light from any of more than one of the emitters when that emitter is activated. The emitters are individually activated in sequential, round-robin fashion and multiple detectors are monitored for each emitter when activated. Interruption of detectible beams between an activated emitter and one of the multiple emitters monitored for the activated emitter. Power applied to an activated emitter is calibrated in steps to a minimum level sufficient to ensure detection by all monitored detectors of light emitted by an activated emitter, plus a safety margin.

Description:
This application is a continuation of U.S. patent application Ser. No. 10/796,428, allowed, filed Mar. 9, 2004 and entitled “METHOD AND SYSTEM FOR ACCOMPLISHING PRODUCT DETECTION,” now U.S. Pat. No. 7,191,034 which is a continuation of Ser. No. 09/935,935 filed Aug. 23, 2001 also entitled “METHOD AND SYSTEM FOR ACCOMPLISHING PRODUCT DETECTION,” now U.S. Pat. No. 6,732,014. This utility application also claims priority through the above-identified applications to U.S. Provisional Patent Application Ser. No. 60/271,998, filed Feb. 27, 2001 and entitled “METHOD AND SYSTEM FOR ACCOMPLISHING PRODUCT DETECTION,” the content of which is incorporated herein by reference. This application includes subject matter protected by copyright. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to the vending arts generally and more specifically to vending machine delivery systems for determining whether a product has actually been delivered to the consumer after a customer order. 
     2. Description of the Prior Art 
     Many vending machines lack the ability to detect and confirm whether an ordered product has been actually delivered to a customer after an ordered vend event by the customer has occurred. A common type of vending machine, referred to herein as “home switch” systems, always assume that the ordered product is available for delivery and that the product is successfully delivered upon completing one vend cycle. 
     However, such vending machines often fail to deliver the product after the vend cycle for various reasons, including improper installation of the products by the vendor&#39;s sales representative or obstructions in the delivery path. Thus, presently in such systems, after paying for the product and a vend cycle occurring, the customer fails to receive the ordered product, resulting in the customer becoming frustrated with the vending company, affecting customer relations and vending sales. 
     BRIEF SUMMARY OF THE INVENTION 
     An optical vend sensing system for use in vending machines employs a row of light emitters on one side of a region through which a vend product passes during delivery and a row of light detectors on the opposite side. Each detector is substantially aligned with a corresponding one of the emitters, and is capable of receiving light from any of more than one of the emitters when that emitter is activated. The emitters are individually activated in sequential, round-robin fashion and multiple detectors are monitored for each emitter when activated. Interruption of detectible beams between an activated emitter and one of the multiple emitters monitored for the activated emitter. Power applied to an activated emitter is calibrated in steps to a minimum level sufficient to ensure detection by all monitored detectors of light emitted by an activated emitter, plus a safety margin. 
     The foregoing has outlined some of the more pertinent objects and features of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention as will be described. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the following DETAILED DESCRIPTION OF THE INVENTION. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an overview of the methodology utilized in the present invention; 
         FIG. 2  shows a schematic diagram of the present invention; 
         FIG. 3A  shows the emitter arm portion of the monitoring system; 
         FIG. 3B  shows the detector arm portion of the monitoring system; 
         FIG. 4  shows the operation of the monitoring system when a customer places an order; 
         FIG. 5  shows the steady state calibration mode of the monitoring system; 
         FIG. 6  shows a typical detector arm attached to a vending machine; and 
         FIG. 7  shows light beam patterns for the emitters in the monitoring system. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention is a vending system that verifies that an actual delivery of an ordered product is made. If the actual delivery fails for a set number of delivery attempts, then the customer is offered one or more alternative choices, including without limitation, choosing an alternative product, or a refund. 
       FIG. 1  is an overview of the methodology utilized in the present invention. The monitoring system is in calibration mode in its normal steady state configuration mode as shown in step  100 . Calibration mode is discussed in greater detail in  FIG. 5  below. The customer orders a product after placing money in the ordering system by depressing a keypad or similar device in step  102 . The vending machine&#39;s ordering system sends a customer order event signal in step  103  to the monitoring system informing the sensing/monitoring system that an order event has occurred in step  102 . The monitoring system subsequently completes its last calibration cycle in step  104  and transitions from steady state calibration mode to the monitoring cycle in step  106 . Upon transitioning, the monitoring system commences its sensing/monitoring cycle by monitoring the product delivery path and sends a ready signal to the product delivery system in step  110 . The monitoring cycle is described in more detail in  FIG. 4 , herein below. After receiving a ready signal from the monitoring system, the product delivery system attempts to deliver a product through the product delivery path in step  120 . If the monitoring system senses or detects the product passing through the delivery path in step  125 , it reports the delivery event to the ordering system in step  130 . Upon receiving the report, the ordering system concludes the transaction with the customer and sends a completion signal to the monitoring system, which returns to steady state calibration mode in step  135 , whereupon the monitoring system enters into calibration mode in step  140 . 
     If the monitoring system does not detect a product in the first delivery attempt in step  125  then it will not send a signal to the ordering system after the step  125 . The invention allows the delivery system to attempt delivery three times or a preset option. In step  150 , if the number of attempted delivery cycles is less than the preset option, then the ordering system thereupon attempts to deliver the product again in step  120 . If the attempted delivery cycles equal the preset option, then in step  155  the customer is granted alternatives to purchasing the first ordered product. Step  155  allows the customer to either ask for a refund or make a selection of a second, different product for delivery and step  153  marks the first ordered product as empty. 
     Step  153  prevents future vend attempts for the first ordered product until the vending machine is visited by a service person. This helps to prevent cheating by a customer if the vending machine reverts to the home switch operation, and helps to prevent further tampering if tampering was the cause of the first vend failure. 
     If the customer chooses a refund, then the present invention delivers a signal to make a refund, in step  160 , whereupon a signal is sent to the monitoring system that the order is complete in step  135  and to the monitoring system to enter into steady state calibration mode in step  140 . If the customer chooses a second, different product, then the present invention returns to  120  and the process proceeds as described above, until the operation is complete. 
       FIG. 2  shows a schematic diagram of the present invention installed in a vending machine  205 . In  FIG. 2  various products  210  are placed in the vending machine&#39;s delivery system  215 . Prior to a customer making a purchase, the monitoring system  217  is in calibration mode. When a customer makes an order through the order system  220 , the monitoring system completes the calibration mode and enters into its monitoring mode. Thereupon, the ordering system allows for an attempted delivery of the ordered product  210 , typically through a helical delivery system  215 . When ordered, product  270  is delivered into delivery space  222 , falling through the delivery path  225  past monitoring system  217 . As it passes the monitoring system, the product momentarily breaks the continuity of the monitoring system&#39;s monitoring devices. If the monitoring system utilizes an optical monitoring system, then as the product passes through the monitoring system&#39;s light plane  234 , be it infrared or otherwise, it momentarily breaks the light continuity and prevents a portion of the light from reaching at least one detector on the opposite side of the monitoring path. The logic circuit on the detecting arm  235  will note the momentary blockage of light and report it as a delivery event. 
     The monitoring system is comprised of an emitter arm  240  upon which are located a set number of one or more emitters  242 , and a detector arm  250  comprising of one or more detectors  252  and located directly across delivery path  225  from the emitter arm  240 . Emitter signals, the total of which comprise light plane  234 , are sent from the emitters  242  to the detectors  252  across the delivery path  225  during both monitoring mode and calibration mode. The emitter arms and detector arms are described in more detail in  FIGS. 3A and 3B . 
       FIG. 3A  shows the emitter arm portion of the monitoring system. In  FIG. 3A , emitting arm  310 A transverses along one side of the delivery path in the vending machine. Emitters  315 A are attached to arm  310 A. The horizontal and vertical placement of emitters  315 A on arm  310 A is determined by the size of the smallest product that crosses the delivery path, and by the type and accuracy of the emitters utilized in the present invention. 
     The emitters may comprise of an optical monitoring device. The spacing of optical emitters is determined by five factors: emitter size, optical diffusion, ambient light, product size and the reflected light. Emitter size and optical diffusion are fixed at the time of construction; however, ambient and reflective light may vary over the course of use of the emitter. Infrared light may be used to help to reduce these effects. However, it is clearly understood and contemplated by the present invention that other types of light sources can be used, including various lasers or white light sources. 
     The body  320 A of the arm  310 A is made of suitable material able to contain the electronic control components  325 A necessary to operate the emitter, including, a power source  330 A, and logic circuitry  335 A. Additionally, holes  340 A are provided to securely fasten and adjust the positioning of the arm  310 A to the vending machine. 
       FIG. 3B  shows the detector arm portion of the monitoring system. The shape and construction of the detecting arm  350 B is related to the shape and construction of the emitting arm  310 A. The detecting arm  350 B is placed on the same plane, parallel to and across the delivery path from arm  310 A (see  FIG. 2  for more details). The detectors  355 B are arranged so that their vertical spacing and horizontal arrangement mirror the emitters&#39; arrangement on arm  310 A. Likewise, the body  360 B of  350 B is constructed of material suitable to contain detection and logic circuitry  365 B, attachment holes  370 B, and a power source  375 B. The choice of the type of detector is directly related to the type of emitter being utilized in the present invention. 
       FIG. 4  shows the operation of the monitoring system when a customer places an order. Prior to placing an order, the monitoring system is in calibration mode in step  400 . Upon placement of the order in step  405 , the monitoring system transitions from its steady state calibration mode  400  into its monitoring mode in step  407 . Once in monitoring mode, the monitoring system begins cycling each emitter by pulsing the emitter individually in step  410 . The monitoring system uses a pulse strength determined from when the system was in the calibration mode. 
     In step  410  an emitter pulses its signal to the corresponding detector across from the emitter, and the two detectors on either side of the detector. Upon pulsing the light, the detector circuitry determines whether the detectors detected the light from the emitter in step  415 . (If the emitter is either the first emitter or the last emitter on the emitter arm, then only the detector across from the emitter and the detector on the non-wall side of the detector is scanned.) 
     If the detector directly across from the pulsing emitter or the side detectors detects the signal in  415 , then the emitter&#39;s logic circuit sequences to the next emitter in line and sends a pulse from that emitter in step  420 . The emitter&#39;s logic circuit continues until after it completes the pulsing of the last detector whereupon, the monitoring system repeats the process, begins again at the first emitter until the detector&#39;s logic circuit receives a detect signal and the monitoring system receives a signal to cease monitoring. 
     If at least one of the three detectors fails to detect a light beam from the emitter during the monitoring cycle, then the logic circuit reports a product delivery to the ordering system in step  425 . Once a report of delivery is made to the ordering system, the ordering system returns a signal to the monitoring system to return to steady state calibration mode in step  430 . Otherwise, the monitoring system continues to monitor until it receives a return to steady state calibration signal from the ordering system because of a refund, if appropriate. 
       FIG. 5  shows the steady state calibration mode of the monitoring system. During the steady state calibration mode, the monitoring system is constantly calibrating itself for optimum performance because temperature, humidity, dust, and alignment conditions fluctuate over the course of system usage. 
     The calibration mode adjusts the light intensity from each emitter as necessary so that each set of three detectors serviced by that emitter receives only enough intensity, plus a small safety margin, to be active in the unblocked condition. This minimizes the adverse affects of reflected light from the emitters and allows for a wider detector aperture (which makes system alignment easier) and reduces the overall power requirements of the system. In step  505 , the logic circuit in the monitoring system determines whether an order has been placed. If an order has not been placed, then the monitoring system proceeds to send a series of pulses to the first of the one or more emitters in step  510 . Upon sending a pulse, the monitoring system queries the emitter&#39;s corresponding detector and each detector on either side of the corresponding detector to determine if those detectors detected the pulsed signal in step  515 . If a signal was detected in each of the three detectors then the monitoring circuitry sequences to the next emitter in step  520 . The emitters typically have adjustable signal power levels associated with the type of emitter used. The calibration mode will attempt to maintain the power level at the level needed to provide just enough signal, plus a safety margin, such that the corresponding detectors detect the signal. If any one of the three detectors does not detect the pulsed signal from the emitter, then in step  530 , the monitoring circuitry determines whether the emitter is operating at its maximum power intensity. If the emitter is not, then the emitter will step increase the signal power level in step  560  and re-send a pulsed signal to the detectors again in step  510 . If the power intensity for that emitter is at its maximum intensity, then the detector will send an error message to the monitoring system in step  540 . The monitoring system will then follow a precoded routine to shut down the entire vending operation, shut down the monitoring system or rely on prior art ordering systems (the home switch method) in step  550 . 
       FIG. 6  shows a typical detector arm attached to a vending machine. Because of the reflective surfaces  610  in the vending machine, small apertures  620  are used to minimize the reflective light from adjacently reflective surfaces  610 . The apertures are narrowed holes located in front of the detectors,  625 , on the detector side of sensing system  630 . The holes inhibit unwanted reflections from adjacent surfaces by blocking much of the light beams that reflect back to the detector arm at wider angles than the apertures allow. 
     Apertures  620  keep the majority of the unwanted light from reaching the detection side of the monitoring system. In addition, the detectors  625  have a usable 60 degree horizontal/30 degree vertical reception angle. Light arriving at the detector at angles greater than these is rejected. Additionally, infrared optical detectors contain optical frequency filters, which reject visible light frequencies, but pass the infrared frequencies of interest. Modulation techniques, whereby the detector only responds to certain signal frequencies from the infrared emitters, may also be used to allow the detectors to distinguish between the ambient light and the desired point source light frequency from the emitter. 
     As mentioned above, product detection may be accomplished by utilizing infrared emitter/detector pairs that can monitor and detect when a signal path is broken. In a typical vending machine&#39;s delivery paths, a set of ten infrared emitter/detector pairs are used to cover the delivery path much like a light curtain. 
       FIG. 7  shows a representative example of a light curtain  730  that may be utilized in the present invention. Typically, nine sets of emitters/detectors are used to cover the main delivery path, while the tenth set is used to cover a gum/mint area. The nine sets that cover the main delivery path implement a technique, which, other than for the first and last emitter, requires that a minimum of three detectors are active for each individual emitter monitor cycle. For those vending machines without a gum or mint section, the tenth emitter may be used for the main delivery area, provided that proper alignment of the ten sets is taken into consideration. 
     This arrangement is illustrated in  FIG. 7 , which shows the light beams  710  of interest for each emitter  720  and detector  725 . The spacing of the emitter/detector sets are chosen to assure that the smallest size traditional product breaks the path of at least one beam when it crosses the light curtain during delivery. The technique of servicing three detectors for each emitter allows the monitor to read multiple light beams, which further reduces this spacing in the majority of the delivery area. A logic circuit determines whether a light beam has been broken. 
     In the monitoring system, the infrared emitter/detector sets are controlled by a microcontroller located on the detector arm. During the monitoring mode, it is necessary to monitor each of the emitter/detector sets separately because of the potential for light bleed-over from adjacent emitters. The timing sequence for each set monitor cycle used during the monitoring mode must be fast enough to ensure that the smallest product will be detected by any one of the detectors when the product passes the monitor plane as it falls from the product storage area. 
     The control software further provides the vending operator an option to revert to home switch operation or to place the vending machine out of service in the event the monitoring system is inoperative. This allows the operator to choose one of two options if the monitoring system is operative: 1. to go out-of-service and thus assure that the customer is cheated since the monitoring system cannot determine proper delivery of a ordered product by home switch operation; or 2. to continue making selections available to the customer under the traditional home switch operation with the risks of non-proper delivery of product that operation implies. 
     The monitoring system controller printed circuit board uses flash memory to store the firmware. This gives the option to perform firmware updates in the field. 
     The vending system has several operating options. These may be viewed and programmed by pressing the PRODUCT CONFIG service key on the keypad located on the inside of the vending machine and pressing the down arrow until the appropriate option is reached. The keypad has an associated display device, such as an LED screen or such other typical devices that allow the operator to view the code and results stored within the system. 
     By depressing the EDIT key, the vendor can choose between “SURE.V ON” or “SURE.V OFF”. “SURE.V OFF” is chosen by the operator only if the monitoring system is not installed or if the operator does not wish to use it at the present time. The remaining options for the PRODUCT CONFIG mode are only visible if “SURE.V ON” is selected and the monitoring system is available. 
     When “SURE.V ON” is selected, the operator may then choose between “OPT&#39;N SURE.V” or “MUST SURE.V”. If “OPT&#39;N SURE.V” is selected, the vending machine operation reverts to home switch operation if the monitoring system is not operating normally because, for example, of an obstruction or loss of communication. If “MUST SURE.V” is selected by the operator, the vending machine operates only if the monitoring system is available for use for the main delivery area. (The gum and mint area does not affect operation of the main area, unless the programmer decides otherwise.) Otherwise, the vending machine becomes temporarily out-of-service until the blockage or other error is corrected. 
     When the operator uses the number keys to program “ANTI.JP xx”, the anti-jackpot protection option against unforeseeable cheating of the vending machine&#39;s monitoring system is activated. “xx” represents the number of empty conditions that disables the entire delivery system for a time period as programmed and decided by the operator (described below). A empty condition occurs when product delivery is not detected and the customer&#39;s money is restored or returned. An “xx” value of “00” disables this anti-jackpot feature. 
     The assumption of this option is that very few system failures to the vending machine&#39;s delivery system occurs. If a significant number of failures, represented by “xx”, do occur then it is assumed that it is because of tampering. Upon reading “xx”, the delivery system is deactivated for a certain amount of time so that money can no longer be refunded because of a vend failure and to discourage a potential thief from attempting to steal either product or money. 
     In this condition, the vending machine either reverts to home switch operation if “OPT&#39;N SURE.V” is active, or the system deactivates and the vending machine goes out of service if “MUST SURE.V” is active. If in “Must Sure.V”, once the programmed deactivation time has elapsed the system is re-enabled and the count towards “xx” is restarted. The total number of system empty selections, the number of anti-jackpot occurrences, and the date and time of the last occurrence are recorded as noted below. 
     The operator programs the number of minutes that the vending system remains disabled because of an anti-jackpot occurrence by selecting the “AJP.TMR xxM” option where “xx” is the time in minutes. If “99” is programmed, then the system remains disabled until the main door closes at the end of the next service call. Closing the main door also resets any anti-jackpot time remaining. 
     Certain system data can be reviewed in the PRODUCT CONFIG mode: 
     “SV.EMPTY xx” returns the number of times that credit was restored or returned because the monitoring system failed to detect a product delivery. 
     “* *.SV xxxx” returns the total number of corrected vends, viewable by selection. These are the vends, which normally would not have delivered product if the present invention was not active. 
     “WO.SV xxxx” returns the number of vends, viewable by selection, made while the monitoring system was disabled for some reason. 
     The MACHINE CONFIG list provides additional options related to the present invention. If the operator selects “FAIL=CASH”, the customer&#39;s money is automatically returned on any failed vend. If “FAIL=CRDT” is selected, the credit is restored to the vending machine for another selection. The customer may press the coin return to retrieve his money. 
     The TEST list provides the test screen for the system. If the operator keys in “SV.TST xxx” the following options are provided: 
     “SV.TST OK” indicates that the monitoring system is operating properly. 
     “SV.TST xx” indicates a block in sensing zone 1-9 with 1 being closest to the glass. “H” indicates the gum &amp; mint is blocked if it is configured. This number is displayed real-time and beeps as it changes. This may be used to test the product coverage of the monitoring system&#39;s sensors, although the accuracy is somewhat less than in actual vend situations because of the data being presented. 
     “SV.TST CAL” indicates calibration values that are high. 
     “EDIT” may be used to view the calibration values. A high calibration may be caused by dirt, misalignment of the system sensors, or a partial blockage of a sensor. 
     A calibration value of “0” indicates a shorted detector. This normally requires a new detector assembly. 
     A calibration value of “1” indicates that zone could not be calibrated. It indicates a blocked or damaged sensor. 
     Calibration values above “A” are abnormal and may require adjustment of the alignment or cleaning of the sensors. 
     “SV.TST COMM” indicates loss of communication with the monitoring system, and allows the operation to check the harness connections between the vending machine controller and the monitoring system&#39;s controller. Diagnostics related to the present invention: 
     “SV.EMPTY nn” shows that selection “nn” was marked as empty because product delivery was not detected. 
     “SV.TST xx” automatically enters the system test screen as a diagnostic message if any blocked sensor, communication error, or calibration error is detected. 
     “AJP.TMR xx.xM” is in the diagnostic list if the anti-jackpot timer is active. It shows the time remaining. 
     “AJP xxX MN/DY HR.MN” is the total number of times the anti-jackpot feature occurred plus the date and time of the last occurrence.