The present disclosure generally relates to systems and methods for detecting a sold-out state for beverage dispensers, and more particularly to systems and methods for wirelessly detecting a sold-out state for beverage dispensers by monitoring the current of an electronic valve.
The following U.S. Patents and Patent Publications provide background information and are incorporated by reference in entirety.
U.S. Pat. No. 8,960,016 discloses a method for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the method comprising the following steps: a. the permittivity of the multi-component mixture is determined based on an electromagnetic measurement, b. a statistical parameter related to the electromagnetic measurement is calculated, c. the density of the multi-component is determined, d. the temperature and pressure are obtained, e. based on the knowledge of densities and dielectric constants of the components of the fluid mixture, and the result from the above steps a-c, the water fraction of the multi-component mixture is calculated, characterized by a method for determining the liquid fraction and flow rates of the multi-component mixture where f. the liquid fraction is calculated based on the statistical parameter from step b and the calculated water fraction from step e using an empirical derived curve, g. the velocity of the multi-component mixture is derived, and h. based on the step a-g, the flow rate of the individual components of the multi-component mixture is calculated. An apparatus for performing the method is also disclosed.
U.S. Pat. No. 4,236,553 discloses an electronic controller for solenoid valve actuated beverage dispensers which allows the operator to automatically dispense properly filled cups of various sizes. A slideably mounted electronic probe is lifted by the lip of the cup positioned under the dispenser spout. Actuation of a switch energizes the solenoid valves starting the dispensing cycle. When the cup is filled to the level of the probe, the solenoid valves are de-energized. Early de-energization of the solenoid valves by bubbles is avoided by adjusting a time delay-off knob so that the proper level will be attained for each class of beverage. Too much or too little ice in the glass will not affect the level. Digital counters record the number of drinks served by size or price.
U.S. Pat. No. 6,058,986 discloses an electronic control for an automatic filling beverage dispensing valve. The dispensing valve includes a valve body, a flow control mechanism and a solenoid. The valve further includes an electrically conductive cup actuated lever for operating a micro-switch that is operatively connected to the electronic control of the present invention. The valve body includes a nozzle and a stainless steel electrical contact for providing electrical connection between the electronic control and the beverage as it flows through the nozzle into a cup. The electronic control of the present invention is microprocessor controlled and includes an internal signal generator which generates a signal independent of the input line frequency supplying the power to the control. This generated signal is buffered and applied to the dispensing cup lever while simultaneously being applied to a reference input of a phase-locked loop detector circuit. When beverage fills a cup to the rim thereof the beverage can flow over the rim and thereby provide an electrical continuity between the electrically conductive lever and the stainless steel contact within the nozzle. Thus, a signal is conducted to an input of the phase locked-loop detector circuit where that electrical signal is compared to the generated reference signal. If the two signals are matched in both frequency and phase, the detector circuit generates a continuity detected signal to the micro-processor. The microprocessor thereby ends dispensing by de-energizing the solenoid.
U.S. Patent Application Publication No. 2019/0194010 discloses a beverage dispensing machine that includes a valve body configured to receive a first fluid and a second fluid and dispense the first fluid through a first orifice and the second fluid through a second orifice. A first valve seal is movable to open and close the first orifice, and a second valve seal is movable to open and close the second orifice. An arm is pivotally coupled to the valve body, and pivoting of the arm relative to the valve body moves the first valve seal and the second valve seal and thereby opens the first orifice and the second orifice. The machine also includes a solenoid valve configured to pivot the arm, and a handle with a leg that is pivotable into and between a rest position in which the valve seals are closed and an active position in which the valve seals are open. As the handle moves from the rest position to the active position, the leg acts on the solenoid valve such that the arm pivots and the valve seals open.
U.S. Pat. Nos. 4,728,005, 4,944,332, 5,537,838, and 6,170,707 also provide general information relating to the current state of the art and are incorporated by reference in their entireties.
This Summary is provided to introduce a selection of concepts that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
One embodiment of the present disclosure generally relates to a detection device for detecting that a source is sold-out for a beverage dispenser, the beverage dispenser dispensing from the source via a valve controlled by a solenoid. A circuit board is configured to be positioned on the valve proximal to the solenoid. A detector is coupled to the circuit board, where the solenoid creates a magnetic field when dispensing from the valve, and where the detector detects the magnetic field created by the solenoid and consequently produces an electrical output. A control system is coupled to the circuit board in communication with the detector. The control system is configured to access threshold data and to compare the electrical output of the detector to the threshold data. The control system indicates that the source is sold-out based upon the comparison of the electrical output to the threshold data.
Another embodiment generally relates to a method for detecting that a source is sold-out for a beverage dispenser, the beverage dispenser dispensing from the source via a valve controlled by a solenoid. The method includes coupling a detector to a circuit board, where the solenoid creates a magnetic field when dispensing from the valve, and where the detector is configured to detect the magnetic field created by the solenoid and to produce an electrical output when the magnetic field is detected. The method further includes providing threshold data accessible relating to the electrical output of the detector when detecting the magnetic field from the solenoid. The method further includes coupling the control system to the circuit board in communication with the detector, where the control system is configured to access the threshold data, and where the control system is configured to compare the electrical output of the detector to the threshold data. The method further includes positioning the circuit board on the valve proximal to the solenoid, where the control system indicates whether the source is sold-out based upon the comparison of the electrical output to the threshold data.
Another embodiment generally relates to a detection device for detecting that a source is sold-out for a beverage dispenser, the beverage dispenser dispensing from the source via a valve controlled by a solenoid that axially translates an armature through a top of a frame containing the solenoid. A circuit board is configured to be positioned on top of the valve proximal to the solenoid, where the circuit board is electrically and fluidly isolated from the solenoid, and where an opening is defined in the circuit board such that the armature extends therethrough. A detector is coupled to the circuit board, where the solenoid creates a magnetic field when dispensing from the valve, and where the detector is configured to detect the magnetic field created by the solenoid and to produce an electrical output when the magnetic field is detected. A control system is coupled to the circuit board in communication with the detector, where the control system is configured to access threshold data. The threshold data includes both a magnitude threshold and a time threshold. The magnitude threshold includes a lower magnitude threshold and an upper magnitude threshold, where a first time crossing occurs when the electrical output of the detector first exceeds the lower magnitude threshold, where a second time crossing occurs when the electrical output of the detector first decreases below the upper magnitude threshold after the first time crossing, and where the time threshold corresponds to an elapsed time between the second time crossing and the first time crossing. The control system is configured to compare the electrical output of the detector to the threshold data, and to indicate that the source is sold-out based upon the comparison of the electrical output to the threshold data.
Various other features, objects and advantages of the disclosure will be made apparent from the following description taken together with the drawings.
The present disclosure is described with reference to the following Figures.
To maintain high quality beverages meeting customer demands for beverage dispensers presently known in the art, it is important for owners to quickly identify when one or more sources of content are sold-out. Sources may include a syrup concentrate and/or a base liquid (such as gasified water) in the context of a soda dispensing machine, for example. One way in which owners currently receive notification that one or more sources have been sold-out is by direct feedback from a consumer. For example, a beverage dispensed from the beverage dispenser may lack the expected color, and/or not have the expected taste or gasification level. The owner would prefer to know of a source being sold-out before this point to avoid customer dissatisfaction.
A more automated notification system is also known in the art. This automated system uses pneumatic switches connected in-line with valves within the beverage dispenser to detect a loss of pressure in tubing that communicates content from the source, such as a bag or bottle, to the dispensing valve when the source is sold-out. However, the present inventors have identified that these pneumatic switches typically cost several dollars each. In the context of a beverage dispenser having multiple sources (e.g. different flavors of sodas, different additives, sweetening options, caffeination options, and/or the like), this system become expensive to outfit. This is true both from a piece part cost standpoint, and for installation and service times.
Pneumatic switches presently known in the art are also physically large, often approximately 2.5×2×0.5 inches uninstalled, which requires adequate clearance within the beverage dispenser to install and house them. Since each of these pneumatic switches must also be connected in line with the tubing between the source and each valve, fittings are also required. This adds further cost and installation time, exacerbates the problem of bulkiness, and also introduces additional risk for leaks and failure.
Furthermore, the nature of these pneumatic switches and the operating mechanisms therein, which include mechanical contacts and springs, provides that there is an inherently limited lifespan before the device will fail. Likewise, these devices are prone to accuracy issues due to sensitive reactions to tolerance limits. This results in inaccurate determinations of sold-out states, and/or drifting performance levels over time.
In contrast, the systems and methods presently disclosed provide for a low cost, no-contact alternative for detecting a sold-out state for one or more sources of content within a beverage dispensing machine. Moreover, the present solutions are applicable both new systems, and as a retrofittable add-on for existing systems.
Each of the sources 6 is fluidly coupled to dispensing hardware 12, which selectively communicates the content for the respective source 6 out via an output nozzle 8. In the embodiment shown, the output nozzle 8 does not directly dispense the beverage into a cup, for example, but is instead fed via lines 9 to a main spout 10. This configuration provides for dispensing beverages in which the content of multiple sources 6 is mixed prior to being dispensed from a single main spout 10. However, it should be recognized that in other examples, the output nozzle 8 for one or more locations 4 may also be its own main spout 10 whereby a combination of sources 6 is not required. In the embodiment of
As shown in
The armature 27 is also a plunger 28, or is coupled to a plunger 28, with the plunger 28 having a seal 29. Axial translation of the plunger 28 selectively seats this seal 29 against a floor 31 to allow or restrict flow between an inlet 18 and an outlet 16 within the electronically actuated valve 14 in a customary manner. In the example shown in
Another exemplary electrically actuated valves 14 is further shown in
However, unlike systems presently known in the art, which provide no mechanism for determining sold-out state without the incorporation of a physically wired system voltage detection previously discussed, the embodiments of
Through experimentation and development, the present inventors have identified that the state of a given source 6, and specifically whether or not it is sold-out, can be detected by monitoring the current flowing through the electronically actuated valve 14 over time. In particular, the time for the electronically actuated valve 14 to transition from a closed state to an open state, upon being requested to do so to dispense a beverage, varies depending upon this sold-out state of the source 6 fluidly connected at the inlet 18. This current may be monitored by a current sensor providing data to a control system 200, which may be integrated into the main controller 5 or a separate ancillary circuit board 50 (
Each exemplary ancillary circuit board 50 defines an opening 123 that allows the armature 27 to remain axially movable within the solenoid coil 24 without obstruction. Each system 100 further includes a detector 125 that produces an electrical output responsible to magnetic fields. In the embodiment of
The detector 125 is particularly coupled to the ancillary circuit board 50 such that the magnetic field created by the solenoid 20 when in operation is detectable by the detector 125. With respect to the embodiment shown in
In each detection system 100 shown, the detector 125 is further operatively coupled to a control system 124 that detects the electrical output produced by the detector 125 responsive to the magnetic field. The control system 124 may be structure like the control system 200 of
As is discussed further below, the control system 124 is configured to analyze the electrical output produced by the detector 125 relative to threshold data 72 stored in memory, which includes threshold times for comparing to the elapsed time of the timer 74, to determine the sold-out state of a source 6, the operational condition of the electrically actuated valve, and other conditional aspects of the beverage dispenser 2. It will be recognized that the threshold times corresponding to a sold-out state (versus a non sold-out state) vary based upon the solenoid, valve, and particular beverage being dispensed, for example. Other factors may also be relevant, including an ambient temperature, the incoming pressure of the beverage, and the like. In certain examples, the threshold time of the configuration is 12 ms, whereby elapsed times for opening the valve in excess of this threshold time correspond to a sold-out state (i.e., the beverage is no longer assisting in the opening process), for example. This analysis may then be communicated with other devices, such as to send notice to an operator of a sold-out state, for example.
Certain aspects of the present disclosure are described or depicted as functional and/or logical block components or processing steps, which may be performed by any number of hardware, software, and/or firmware components configured to perform the specified functions. For example, certain embodiments employ integrated circuit components, such as memory elements, digital signal processing elements, logic elements, look-up tables, or the like, configured to carry out a variety of functions under the control of one or more processors or other control devices. The connections between functional and logical block components are merely exemplary, which may be direct or indirect, and may follow alternate pathways.
The processing system 210 may be implemented as a single microprocessor or other circuitry, or be distributed across multiple processing devices or sub-systems that cooperate to execute the executable program 222 from the memory system 220. Non-limiting examples of the processing system include general purpose central processing units, application specific processors, and logic devices.
The memory system 220 may comprise any storage media readable by the processing system 210 and capable of storing the executable program 222 and/or data 224 (such as threshold data 72 and time thresholds TT). The memory system 220 may be implemented as a single storage device, or be distributed across multiple storage devices or sub-systems that cooperate to store computer readable instructions, data structures, program modules, or other data. The memory system 220 may include volatile and/or non-volatile systems, and may include removable and/or non-removable media implemented in any method or technology for storage of information. The storage media may include non-transitory and/or transitory storage media, including random access memory, read only memory, magnetic discs, optical discs, flash memory, virtual memory, and non-virtual memory, magnetic storage devices, or any other medium which can be used to store information and be accessed by an instruction execution system, for example.
The present inventors has identified that high speed data collection electronics (such as within the control system 200 discussed above) are not currently used in the beverage industry, and particularly to ascertain when a source 6 is sold-out or not going to meet specification.
As is discussed further below, the presently claimed system 1 provides that when dispensing hardware 12 is turned on to dispense product, the current through the dispensing hardware 12 is monitored. This current begins to increase as a magnetic field builds up, before the electronically actuated valve 14 has opened. At a point later in time, (e.g., once the armature 27 of the solenoid 20 within the electronically actuated valve 14 begins to move, the inventors have recognized that a back EMF is then generated, which modifies the shape of the current.
Through experimentation and development, the inventors have identified that these changes in current can be detected, and that the shape of the current waveform further changes depending on whether or not the source 6 is sold-out. Specifically, the presence of content within a source 6 creates a force against the valve that either aids or opposes the opening operation, thereby impacting the speed of such action. The speed of opening the electronically actuated valve 14 also depends upon the valve's construction, the content, and the path the content travels in flowing therethrough. In certain embodiments, electronically actuated valves 14 are characterized by taking samples of the current with no media present, which is then used as a reference for each successive operation of the electronically actuated valves 14. It will be recognized that other electrical characteristics of the valve's operation may be monitored in addition to or as alternatives to current, including voltage and/or power of the valve, for example. In a similar manner, an integral of the area under the electrical waveforms discussed further below (e.g.,
The same principles apply when the valve is later closed. Depending on the electronically actuated valves 14 topology, the state of the source 6 either aids or inhibits the closing process, thereby impacting the time for such closing.
In the waveforms shown, the current 64 crosses the lower magnitude threshold LMT and upper magnitude threshold UMT at threshold crossings TC1-TC4. When an electronically actuated valve 14 is initially powered on, indicating a transition from the de-energized phase 68 to the energized phase 66, the current 64 first exceeds the lower magnitude threshold LMT (at the first threshold crossing TC1), then also the upper magnitude threshold UMT. The control system 200 begins counting an elapsed time since the current 64 first crossed over the lower magnitude threshold LMT at the first threshold crossing TC1. As can be seen in
The inventors noted that the elapsed time between threshold crossings TC1 and TC2, or between the current 64 first exceeding the lower magnitude threshold LMT (at first time threshold crossing TC1, the start of the energized phase 66) and the temporary dip between the upper magnitude threshold UMT and lower magnitude threshold LMT occurring coincident with the electronically actuated valve 14 opening (second threshold crossing TC2), varies depending on whether the source 6 supplying the fluid at the inlet 18 is sold-out. Since the pressure provided by the content of the source 6 in the configuration shown in
One or more time thresholds are then provided within the threshold data 72, whereby an elapsed time for opening that is below the threshold corresponds to a non-sold-out state, whereas an elapsed time at or above the threshold corresponds to a sold-out state for the source 6, for example. In the case in which a single electrically actuated valve 14 is fed by two or more sources 6, multiple time thresholds may exist corresponding to one or multiple of the sources being sold-out, for example.
In certain embodiments, the system is configured to learn the specific characteristics of a given fluid, for example via machine learning or artificial intelligence, including changes to the valve observed over time (e.g., due to wear, etc.). In certain embodiments, the control system 124 uses a lattice sense offline machine learning FPGA, for example trained using TensorFlow developed by the Google Brain Team, along with the Lattice Diamond compiler by Lattice Semiconductor™. By incorporating offline machine learning, control system 124 may function without the need for network connectivity to a cloud 202 or other devices such that the threshold data 72 is independent. A library may be generated such that specific data is available across an entire catalog of beverage offerings such that analysis is automatically performed based on the specific content provided at the corresponding source 6 (such as stored data for cola, root beer, fruit punch, iced tea, water, and carbonated water, for example).
If it is determined in step 306 that the current 64 does not exceed the lower magnitude threshold LMT, the electronically actuated valve 14 is determined in step 308 to be in the deenergized phase 68 (see
As discussed above, in the configuration shown in
In certain embodiments, the detection system 100 itself may provide some kind of indication that the source 6 has been identified as being sold-out, such as a visual or auditory indicator coupled to the ancillary circuit board 50. In other embodiments, the detection system 100 instead provides a signal to the main controller 5 of the beverage dispenser 2 to instead trigger indicators already available in the base machine, such as alarms, lights, messages, or communication to the operator via wireless or other protocols. Particularly cases in which the ancillary circuit board communicates wirelessly, the presently disclosed system provides for seamless integration as a retrofittable option for existing systems, not requiring any additional wiring.
The detection system 100 shown in
In certain embodiments, the presently disclosed detection system 100 provides “smart” functionality to enable such features as trending performance and predicting maintenance needs, for example by monitoring the magnitude of electrical outputs produced by the detector 125 over time compared to expected thresholds for solenoids 20 in good working order. In this manner, the presently disclosed systems and methods may be used to enable an otherwise known base beverage dispenser 2 to join an Internet of Things (IOT) network, for example via a cloud 202 (
In certain embodiments, the detection system 100 is powered by a power source (not shown) that is external, such as from the electrically actuated valve 14 and/or the beverage dispenser depending upon convenience. This power source may also be provided by separate circuitry as an add-on device. However, the inventors have identified that the power necessary for operating the detection system 100, including the control system 124, may alternatively be extracted via induction from the coil 24 of the electrically actuated valve 14 itself, specifically via the magnetic field produced by the solenoid 20. This embodiment is particularly applicable in configurations in which the detector 125 is a coil 128 comprised of a wire 131 wrapped around a bobbin 132 (see
Under detection methods known in the art, any detection hardware is required to share power with the existing electrically actuated valve 14. Even in simple configurations, this sharing can lead to the introduction of noise into the electrically actuated valve 14, the detection system 100, or both. Likewise, these known systems and methods mandate finding space for routing the additional wiring in a beverage dispenser, where space is already at a premium. As described above, harvesting power wirelessly through the use of a coil 128 isolates the detection system 100 from the electrically actuated valve 14, providing better reliability for data transport. Similarly, since the detection system 100 has no moving parts or switches, reliability is further bolstered over other mechanisms for detecting the movement of the solenoid 20, and particularly the armature 27.
The present detection system 100 also simplifies the installation process and reduces the need for space. The ancillary circuit board 50 may simply be positioned atop the existing solenoid 20 with no fluid coupling, nor power or communication connections required. In addition, the presently disclosed systems and methods are operable with any brand, make, or model of electrically actuated valve 14, provided it operates through use of a magnetic field produced by the existing solenoid 20.
Next, the detector 125 (which may be the same as the coil 128, or may be a Hall Effect sensor 126, for example) produces an electrical output responsive to the SMF produced by the solenoid 20, which the control system 124 then detects, in steps 406 and 208, respectively. The control system 124 then communicates in step 410 to a stable system, such as a controller 5 contained within the beverage dispenser, and/or with a cloud 202 or IOT network to share the on state status of the solenoid 20. This communication may be wireless as discussed above, such as through Bluetooth®, Wi-Fi, and/or other protocols (e.g., such as may be used for access badges in a building security system). In other embodiments, such as those in which the detection system 100 is built into an electrically actuated valve 14, communication may occur by virtue of other wiring coupled between the beverage dispenser and the electrically actuated valve 14 for operation of the valve, for example.
This communication between the detection system 100 and the stable system continues such that detection system 100 reports this on state as long as the detector 125 continues to produce an electrical output. The stable system uses this information from the control system 124 to determine a start time for the on state of the solenoid 20, and also to start counting an elapsed on timer 74 in step 412. Once the solenoid is deactivated in step 414, the detector 125 no longer produces an electrical output and power to the detection system 100 is lost. The stable system then determines an end time of the on state for the solenoid 20, and stops counting the elapsed time in step 416. This information may then be taken in step 418 for developing analytics data based on the start time, end time, and elapsed time for the on state of the solenoid 20. This analytics data may be used to determine usage times, inferred volumes based on the knowledge of on state times and flow rates for a particular electrically actuated valve 14, and/or other information relating to operation of the electrically actuated valve 14 and when the solenoid 20 therein is in the on state versus the off state.
The functional block diagrams, operational sequences, and flow diagrams provided in the Figures are representative of exemplary architectures, environments, and methodologies for performing novel aspects of the disclosure. While, for purposes of simplicity of explanation, the methodologies included herein may be in the form of a functional diagram, operational sequence, or flow diagram, and may be described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance therewith, occur in a different order and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology can alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all acts illustrated in a methodology may be required for a novel implementation.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. Certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes only and are intended to be broadly construed. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have features or structural elements that do not differ from the literal language of the claims, or if they include equivalent features or structural elements with insubstantial differences from the literal languages of the claims.
This application claims the benefit of U.S. Provisional Patent Application Nos. 62/930,296 and 62/933,725, filed Nov. 4, 2019 and Nov. 11, 2019, respectively, which are incorporated herein by reference in their entireties.
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