Flowmeter assembly

A beverage dispenser provides numerous inventive features in its refrigeration system, diluent delivery system, concentrate delivery system, mixing and dispensing system, and control system. The refrigeration system employs a plate heat exchanger to provide on demand refrigeration of an intermittent water flow. The diluent delivery system includes a flowmeter/solenoid/check-valve assembly. The concentrate delivery system employs a positive displacement pump. The mixing and dispensing system includes a mixing nozzle that has a locking feature such that an elevated blocking surface directly faces the inlet of pressurized diluent to create turbulence. The control system receives package-specific information from a scanner and diluent flow rate information from the flowmeter, and then determines the pump speed in order to set a desired mix ratio.

TECHNICAL FIELD

The invention generally relates to liquid or semi-liquid dispensing systems in general, and more particularly, to beverage dispensers where one or more concentrates are mixed in a potable liquid according to a predetermined ratio.

BACKGROUND OF THE INVENTION

Liquid dispensers are widely used in various industries. Chemical solutions including fertilizers, pesticides, and detergents and so on are often mixed from various concentrates and solvents before dispensed for use or storage. Similar dispensers also find applications in the medical field. In the food and beverage industry, liquid dispensers are widely used in all kinds of venues such as quick service restaurants.

The liquid dispensers used in food and beverage industry reconstitute juice syrup concentrates with a potable diluent, e.g., potable water, and then dispense the reconstituted juice into a container at the point of consumption. This kind of dispensers are sometimes called “postmix” dispensers as they produce a final product in contrast to a “premix” beverage that is prepackaged with the final constituents (flavor, gas, etc.) and ready for consumption. For safety and taste reasons, a postmix beverage dispenser often requires refrigeration in the dispenser of various components that eventually go into the postmix product.

Existing liquid dispensing apparatuses used in the food and beverage industry have become more and more complex in an effort to meet increasingly specific demands from customers. As a result, these dispensing apparatuses have become bulkier and more difficult to service. With the rapid growth in quick service restaurants and the counter space being at a premium, however, there is a strong need for machines of a smaller footprint while easier to service. A smaller machine that is easy to diagnose any operational problems and easy to change parts will further fuel the growth of the industry.

SUMMARY OF THE INVENTION

The present invention relates to various features of an improved liquid dispenser. These features will be discussed, for purpose of illustration, in the context of food and beverage industry but should not be contemplated to be limited to such applications.

The present invention combines the functions of redirecting liquid flow, measuring flow rate, regulating flow pressure and gate-keeping into one compact module. Further, connectors that readily join with conduits upstream and downstream are fitted into the assembly. The resulting apparatus saves space and is easy to replace.

In one aspect, the invention provides an integrated module for monitoring and regulating fluidic flow and a beverage dispensing apparatus incorporating such a module. The module includes a manifold, a flowmeter, an adapter, a pressure-compensated flow-control valve, and a gate-keeping valve. The manifold is in fluid communication with at least one inlet port for fluid input and at least one outlet port for fluid output. The flowmeter is integrated in the manifold and situated downstream to the inlet port and upstream to the outlet port; the flowmeter is responsive to a fluid flow by generating an output indicative of a rate of the fluid flow. The adapter is adjacent to the flowmeter and configured to accommodate a sensor for sensing and relaying the output generated by the flowmeter. The pressure-compensated flow-control valve is integrated in the manifold upstream to the flowmeter and configured to regulate fluid flow into the flowmeter. The gate-keeping valve, e.g., a solenoid valve, is fastened to the manifold and situated downstream to the flowmeter and upstream to the outlet port, and the gate-keeping valve is configured to control the fluid flow. The module may further include a one-way valve, e.g., a check valve, integrated in the manifold downstream to the flowmeter to prevent any substantial fluid flow back toward the flowmeter.

In one embodiment, the manifold is injection molded. Further, the assembly may include a first connector assembly configured to fit inside the inlet port for sealingly receiving an upstream conduit; and a second connector assembly configured to fit inside the outlet port for sealingly receiving a downstream conduit. At least one of the connector assemblies may be a quick disconnect fitting and/or include an o-ring. There may be an integral housing embodying at least the pressure-compensated flow control valve, the manifold, and the flowmeter.

In another aspect, the invention provides an integrated module that includes the manifold, the flowmeter, the adapter, the gate-keeping valve and the connector assemblies. The module may further include the pressure-compensated flow-control valve. In one feature, a beverage dispensing apparatus incorporating such a module is also provided.

In yet another aspect, a method for making an integrated module that monitors fluidic flow is provided. The method includes the steps of:

(a) providing a pressure-compensated flow control valve, a flowmeter and a one-way valve;

(b) providing an integral housing defining a bore from an inlet port to an outlet port, and assembling inside the integral housing the pressure-compensated flow control valve, the flowmeter and the one-way valve, wherein the pressure-compensated flow control valve, the flowmeter and the one-way valve are arranged sequentially down a fluid flow along the bore; and

(c) fastening a gate-keeping valve to the integral housing.

The method may further include the steps of furnishing a first connector at the inlet port for sealingly receiving an upstream conduit, and furnishing a second connector at the outlet port for sealingly receiving a downstream conduit.

DETAILED DESCRIPTION OF THE INVENTION

Features of the invention may work by itself or in combination as shall be apparent to by one skilled in the art. The lack of repetition is meant for brevity and not to limit the scope of the claim. Unless otherwise indicated, all terms used herein have the same meaning as they would to one skilled in the art of the present invention.

The term “beverage” as used herein refers to a liquid or a semi-liquid for consumption, and includes but are not limited to, juices, syrups, sodas (carbonated or still), water, milk, yogurt, slush, ice-cream, other dairy products, and any combination thereof.

The terms “control system,” “control circuit” and “control” as a noun are used interchangeably herein.

The term “liquid” as used herein refers to pure liquid and a mixture where a significant portion is liquid such that the mixture may be liquid, semi-liquid or contains small amounts of solid substances.

The present invention provides a liquid or semi-liquid dispenser that refrigerates a liquid flow inside the dispenser on demand. By “on demand,” it is meant to refer to the capability for chilling a target without significant delay. Typically for a beverage dispenser, e.g., those used in the quick service restaurants, fluid flows inside the dispenser are intermittent. The beverage flow may be almost continuous during meal hours, but may have extended idle time up to hours during slow time. Existing beverage dispensers that use a cold reserve such as an ice bank necessitate constant replenishing of the reserve as the reserve constantly dissipates heat, a wasteful system that often requires constant maintenance and service by human operators.

To be able to handle both the busy and slow hours in usage without constantly wasting energy, a desirable refrigeration system needs a high degree of efficiency in the heat-exchange section of the refrigeration system. The present invention provides such a refrigeration system designed to function in a liquid dispenser. Examples of such a liquid dispenser are now described.

Referring toFIG. 1, a postmix beverage dispenser50according to one embodiment of the present invention is illustrated. The beverage dispenser50, viewed from outside, includes a housing52that has a hinged front door54. The housing52further includes a platform or drip tray56for placing receptacles58such as cups of various sizes that receive the postmix products. Dispense buttons60aand60bmay be situated at various locations on the housing52for an operator to initiate a dispensing cycle. In the particular embodiment illustrated inFIG. 1, one set of the dispense buttons,60aor60b, is situated on either side of the drip tray56to control dispensing of the product from either dispensing nozzle (not shown). To have the dispense buttons at a location other than the front door54, makes it easier for wiring, and also the buttons remain visible and accessible to the operator while the front door54is open.

The dispensing buttons60aand60bmay include, as in the example illustrated, buttons corresponding to various portion sizes, e.g., small, medium, large and extra large. The buttons may also include those that allow the operator to cancel/interrupt a dispensing cycle that has started, or to manually dispense while the button is pressed (“top-off” or “momentarily on”). They may also include lights that indicate the status of the machine. The dispensing buttons60aand60bmay be back-lit to enhanced visibility, and may be part of a larger display (or interface) that provides further information on the dispenser.

Still referring toFIG. 1, a display62, e.g., a liquid crystal display, is illustrated underneath the drip tray56and on the dispenser housing52for displaying information pertaining to the machine. Such information may include error messages, status, diagnostic messages, operational instructions, and so on. Similar to the dispense buttons, having the display62off the front door54can be advantageous in terms of wiring and functionality. Other parts of the dispenser housing52may include metallic panels64with slots66for air intake needed for the refrigeration system.

Referring now toFIG. 2, a cut-away view of the dispenser50reveals its various inner parts. Inside the housing52and behind the front door54is a concentrate cabinet68(or compartment) for placing a prepackaged supply of concentrate and for mixing the concentrate with a diluent before dispensing. In one embodiment, the cabinet68houses at least one, preferably two, concentrate holders70, one of which is shown in the drawing. A prepackaged supply (not shown) of concentrate (or additive, solute) is stored inside the concentrate holder70and a drainage tube72from the concentrate supply is fed into a concentrate delivery system74, which in turn, delivers the concentrate into a mixing and dispensing system76. Diluent (or solvent), typically a potable liquid, e.g., potable water, carbonated or non-carbonated, is supplied through a separate delivery system, e.g., a water delivery system78, into the mixing and dispensing system76. Postmix product is eventually dispensed through a mixing nozzle80into the receptacle58.

Still referring toFIG. 2, the beverage dispenser50also includes a refrigeration system82that provides the necessary refrigeration to chill the concentrate cabinet68and water supplied through the water delivery system78. In one embodiment, a control system84is provided to monitor, regulate and control the operation of various systems inside the dispenser50, such as the refrigeration system82, the concentrate delivery system74, the water delivery system78, and the mixing and dispensing system76. The control system84may also provide error diagnostics for a service technician or operator.

A power switch85is located on the dispenser housing52, specifically, outside of the drip tray56in the illustrated embodiment. A plug86at the back of the dispenser housing52connects systems that require power to an outside power source. Various parts, for example, of the water delivery system78and/or refrigeration system82, are wrapped in insulation materials88.

In a preferred embodiment, one beverage dispenser50contains at least two production lines such that most of the parts described above in reference toFIG. 2are duplicated side-by-side in the same dispenser housing52. For example, two sets of concentrate holders70, concentrate delivery systems74, parts of the water delivery systems78, mixing and dispensing systems76may be manufactured to fit into one dispenser50. The refrigeration system82is also bifurcated where necessary to chill both production lines. With two production lines, an operator has the choice of providing two different postmix products through the same dispenser. In one embodiment, the footprint or dimension of the dispenser50is no larger than about 11 inches (about 28.0 cm) wide, about 25 inches (63.5 cm) deep and about 55 inches (88.9 cm) tall. To save space, various individual parts inside the dispenser50may be designed as integrated modules to reduce extraneous connecting or sealing parts and to make it easier for service.

Features of the present invention are further illustrated by the following non-limiting examples.

Refrigeration System

Referring now toFIG. 3, an embodiment of the refrigeration system82according to the present invention is illustrated. In one embodiment, the refrigeration system82includes one or more evaporators, a compressor90, a condenser92, a fan94, an air filter96, a dryer98, and one or more optional temperature sensors, parts generally known to one skilled in the art. Under the control of the control system84, the refrigeration system82cools both the concentrate cabinet68and the water delivery system78. In one embodiment, the control system84is programmed to prevent use of the refrigeration system82if the filter96is not installed. This prevents the fan94from engaging and, consequently, protects the condenser92from contamination by unfiltered air flow. A simple reed switch next to the filter96providing feedback to the control system84is able to accomplish this. Furthermore, in order to provide refrigeration to the water delivery system78on demand, the present invention includes a plate heat exchanger, for example, a brazed plate heat exchanger (BPHX)100, in its refrigeration system82.

An illustrative refrigerant circuit is shown inFIG. 4, where the refrigerant flows through the compressor90, the condenser92next to the fan94, and various valves102including solenoid valves that direct the flow of the refrigerant. The circuit includes a primary loop104that chills the water supply and a secondary loop106that chills the concentrate cabinet68.

In one embodiment, the primary loop104lowers the water supply, e.g., a pressurized water supply at a flow rate of about 4 ounces (about 0.12 liters) per second or about 2 gallons (about 3.8 liters) per minute, by at least 5° F. (about 2.8° C.), or preferably, 10° F. (about 5.6° C.). And the secondary loop106keeps the concentrate cabinet at or below 40° F. (about 4.4° C.). In one feature, in order to guarantee almost instant chilling of the water supply, the primary loop104and the secondary loop106are never activated simultaneously—only one loop is being activated at any given time. And the primary water loop104always has priority over the secondary cabinet loop106. In another feature, water from the beverage tower or a water booster/chiller system is channeled to flow in and out of the BPHX100for maximum efficiency in heat exchange.

Referring now toFIG. 5where the BPHX100is illustrated in an exploded cut-away view. The BPHX100comprises multiple corrugated layers of thin stainless-steel plates108that are gasketed, welded, or brazed together. Such BPHX are commercially available, for example, from Alfa Laval Corporation. In one embodiment, the BPHX100is brazed with copper or nickel materials, and called copper brazed plate heat exchanger. In another embodiment, the BPHX100is a stainless steel brazed plate heat exchanger. The corrugated BPHX plates108provide maximum amount of heat-exchange surfaces as a water conduit110formed on one plate is situated next to a refrigerant conduit112formed in a neighboring plate.

Both the refrigerant and the water are controlled by solenoids such that the water will only flow through the BPHX100when the refrigerant is flowing, and vise versa, creating instant yet energy-conserving heat transfer. In one embodiment, water and refrigerant flow in a co-flow pattern, which means they both flow from one side of the exchanger, top or bottom, to the other. In a preferred embodiment, water and refrigerant flow in a counter-flow pattern, where warm water flows in from the top of the exchanger and cold refrigerant flows in from the bottom of the exchanger. As a result, as the water is chilled, it passes by even colder refrigerant as it progresses through the exchanger, forcing a rapid decrease in the water temperature. As a result, the refrigeration system of the present invention is capable of chilling a water flow on demand without the use of a cold reservoir such as an ice bank. In other words, the refrigeration system operates in an ice-free environment.

To prevent accidental freeze-up of the water circuit, the control system of the dispenser is programmed to prevent actuation of the refrigeration system before a sufficient amount of water has entered the circuit. For example, if the BPHX holds 12 ounces (about 0.35 L) of water, and it is determined that, from the point where water flow is measured (e.g., at a rotameter), at least 21 ounces (about 0.62 L) of water is needed to ensure the water conduit inside the BPHX is filled up, the control system will be programmed to mandate 21 ounces (about 0.62 L) of water has passed through the rotameter in each power cycle before energizing the primary water chilling loop of the refrigeration system.

Referring back toFIG. 4, the secondary cabinet loop106of the refrigeration system82can utilize any of the conventional refrigeration technique, e.g., the cold-wall technology, to chill the concentrate cabinet68. Because the dispenser stores and makes products for consumption, it is important to maintain the concentrate cabinet68at a temperature that substantially inhibits growth of potentially harmful bacteria, e.g., at or below 40° F. (about 4.4° C.). In one embodiment, the secondary cabinet loop106utilizes a capillary tube refrigerant control scheme since the load on the system is fairly constant.

Diluent Delivery System

Referring toFIG. 6, an embodiment of the water delivery system78is illustrated. Potable water is introduced into the delivery system78at an inlet114at the back of the dispenser. The inlet114is fitted to allow a 0.5 inch (1.27 cm) NPT (National Pipe Tap) inlet connection to an outside source of water supply, e.g., an in-store water chiller/booster system. The incoming water may be boosted, e.g., to about 20 to 100 psi (pound per square inch), and pre-chilled to about 45° F. (about 7.2° C.). The water deliver system78, in one embodiment, provides pressurized water flow as the master in a “master-follower” mixing system. Such a system regulates the rate of delivery for the follower, the concentrate in this case, based on that of the master, water in this case, and therefore, only actively adjusts the rate for one of two ingredients. The water delivery system78may also, in corroboration with the refrigeration system82, provides further chilling of the incoming water, e.g., by an additional 5° F. (about 2.8° C.) to 40° F. (about 4.4° C.). For that reason, parts or all of the water delivery system78, including water conduits116aand116b, are insulated.

Still referring toFIG. 6, the water delivery system78continues as water conduit116apasses through an optional pressure regulator118. The pressure regulator118may adjust the water flow to a desired pressure and flow rate, e.g., less or at about 30 psi and about 2 gallons (about 3.8 L) per minute. Pressure-adjusted water is then fed into part of the refrigeration system82, specifically, the BPHX100. Further chilled water exits the BPHX100into the conduit116b. Because the illustrated embodiment has two production lines from two sources of concentrate supply, water is bifurcated here and flows into two flowmeter assemblies120aand120bbefore entering respective mixing and dispensing systems76aand76b, and dispensed as part of the final products eventually.

Referring now toFIG. 7, the flowmeter assembly120is designed to minimize extraneous parts, connectors and fixtures while combining the functions of flow control and monitoring into one assembly. In one embodiment, the flowmeter assembly120includes a manifold122inside an integral housing123that has a first arm124and a second arm126. The first arm124provides at least one inlet port128for fluid input, and the second arm126provides at least one outlet port130for fluid output. The inlet port128is in fluid communication with the outlet port130through a bore (not shown). The orientation of the second arm126determines the direction of fluid output. In one embodiment, the second arm126is constructed along an axis that is about 45 to 60 degrees to the axis of the first arm124.

Referring still toFIG. 7, a flowmeter or rotameter (not shown) is embedded or otherwise integrated in the first arm124of the manifold housing123, downstream to the inlet port128and upstream to the outlet port130. The flowmeter responds to any fluid flow by generating an analog output signal indicative of the rate of the fluid flow. Next to the flowmeter on the first arm124is an adapter132configured and sized for a flowmeter sensor134to fit in its groove. The flowmeter sensor134senses the output signal generated by the flowmeter and relays through wiring136to a control system. The control system uses this information to set the pace of a concentrate pump to achieve a desired concentrate ratio as explained in a subsequent section. To ensure accurate reading, upstream to the flowmeter, an optional pressure-compensated flow control valve (not shown) may be incorporated in the first manifold arm124to regulate water flow into the flowmeter. The pressure-compensated flow control valve is preferably a one-way valve. Additionally, another one-way valve, e.g., a check valve (not shown), may optionally be embedded in the second housing arm126to prevent any substantial fluid flow back toward the flowmeter. Backflow from the mixing system may contaminate the flowmeter and prevent it from proper functioning.

Still referring toFIG. 7, in order to minimize the amount of connecting parts in the water delivery system, the ports of the flowmeter assembly120are equipped with furnishings that allow the assembly to sealingly receive upstream and downstream conduits, preferably of a standard size, e.g., 0.5 inch (1.27 cm) in diameter. Specifically, the inlet port128and the outlet port130are furnished with connector assemblies138and140, respectively.

The flowmeter assembly120further includes a gate-keeping valve, e.g., a solenoid valve142sealingly fastened to the manifold housing123and situated downstream to the flowmeter and upstream to the outlet port130. The solenoid valve142is capable of shutting off and reopening the water flow, and is needed to control water flow from the BPHX to the mixing system. In the illustrated embodiment, the solenoid valve142is pre-fabricated and then fastened onto the manifold housing123though a screw144.

Referring now toFIG. 8, more details of the flowmeter assembly120are illustrated in an exploded view. To manufacture the assembly120, in one method, a pressure-compensated flow control valve145, a flowmeter146with a turbine148, and a check valve150, all commercially available, are provided. Then, the manifold housing123can be fabricated, e.g., through injection molding using an NSF-listed food-grade thermoplastic, while assembling therein the pressure-compensated flow control valve145, the flowmeter146, the check valve150, arranged sequentially down a fluid flow along the bore of the manifold. For the particular manifold configuration illustrated herein, a port plug152is used to seal up a reserve port153on the housing123. A commercially available solenoid valve142is then fastened to the manifold housing123through a two-way bolt screw144and a top nut154.

Still referringFIG. 8, connector assemblies138and140may be furnished to the inlet port128and the outlet port130, respectively, after the manifold housing123has been fabricated. In one embodiment, the connector assembly is a quick disconnect fitting, and may include an expandable member configured to fit inside the port for sealingly receiving a connective conduit. As illustrated herein, each of the connector assemblies138and140may include a barbed expandable member156with an external o-ring158for sealing. In one embodiment, the expandable member156comprises multiple extensions arranged in a circle and separated by slots. For example, this kind of connector assembly is commercially available from Parker Hannifin Corporation of Ravenna, Ohio, under the trademark TrueSeal. Again, a flowmeter sensor134can be fastened to the flowmeter assembly120through an adapter structure132on the manifold housing123.

By integrating multiple components such as the pressure-compensated flow control valve, the flowmeter (and/or its sensor adapter), the solenoid valve, and the check valve into one manifold-based assembly, the present invention economizes all these parts into one easily serviceable assembly with only two openings. Further, the assembly is designed such that those limited number of openings can be furnished with connectors than can sealingly connect to other conduits though simple axial motions without the help of any tools, further enhancing serviceability. An integrated assembly also makes it easier to fabricate closely-molded insulation wrap or casing around it.

Concentrate Delivery System

Referring toFIG. 9, in one embodiment of the invention, the concentrate delivery system74delivers the concentrate from a reservoir into the mixing and dispensing system76where the concentrate meets the diluent, e.g., potable water, and the two are blended together before being dispensed.FIG. 9shows the dispenser embodiment 50 ofFIGS. 1 and 2with the front door removed, and one of the two parallel production lines is depicted in a partly exploded view.

The concentrate, which may be liquid or semi-liquid and may contain solid components, e.g., juice or syrup concentrates with or without pulp, slush, and so on, is loaded into the concentrate cabinet68in a package. The package may be a flexible, semi-rigid or rigid container. A concentrate holder70may be provided to accommodate the concentrate package. In one embodiment, the concentrate holder70is a rigid box with a hinged lid that opens to reveal a ramp162, separate or integrated with the holder housing, to aid drainage of the concentrate from its package. The ramp162can be flat or curved for better accommodation of the package. The concentrate holder70may also have corresponding ridges164and grooves166on its housing, e.g., the lid160and its opposite side168, to aid stacking and stable parallel placement. The concentrate holder70may also have finger grips or handles that are easily accessible to an operator from the front of the concentrate cabinet68to aid the holder's removal. For example, a vertical groove165near an edge of the holder70could serve that function.

Referring to bothFIGS. 9 and 10, the concentrate package comes with a drainage tube72that is lodged in an opening170at the bottom of the concentrate holder70. The concentrate holder70may include a protrusion or similar structure to facilitate the locking of the drainage tube72in a preferred locking position in the opening170to prevent kinking or misalignment that hinders pump operation. Further, such a locking position may ensure proper functioning of a sensor that monitors the liquid flow inside the drainage tube. The drainage tube72extends out of the concentrate holder70and is attached to a tube adapter171on the top of a pump head172. Underneath the tube adapter171is an elongated cylindrical piston housing176inside which a piston177, actuated by a rotary shaft (not shown) powered by a motor181, moves to transfer the concentrate from the tube adapter171to a mixing housing178. Inside the mixing housing178are portions of a mixing nozzle80of which the top surface182forms a mixing chamber184with the top inner surface of the mixing housing178. Water is also delivered into the mixing chamber184where mixing takes place. The reconstituted product is then dispensed through the discharge outlet186of the mixing nozzle80.

Still referring to bothFIGS. 9 and 10, the pump head172is mounted onto an adapter plate188through a locking ring190. In one embodiment, the locking ring190has a feedback structure that ensures the locking ring190is in the proper locking position. As a result, the dispenser machine50is not energized unless the pump head172and the locking ring190are properly assembled. An example of such a feedback structure is a magnet192that activates a reed switch194(FIG. 10) placed behind the adapter plate188at a position that corresponds to the proper locking position of the magnet192.

Referring now toFIG. 11, in a more detailed view, the piston177is shown to extend out of an upper opening196of the adapter plate188. The piston177has a U-shaped depression180(better illustrated inFIG. 12) that temporarily holds concentrate during its operation. Still referring toFIG. 11, as the piston177transfers the concentrate from the drainage tube72towards nozzle top surface182, pressurized and chilled water is forced out of a lower opening198of the adapter plate188to mix with the concentrate. The blended product then flows through an opening202in the nozzle top surface182.

According to one feature of the invention and referring back toFIG. 10, the piston177is, for example, part of a positive displacement pump, e.g., a nutating pump or a valveless piston pump, such as those commercially available from Micropump Incorporated of Vancouver, Wash. Nutation is defined as oscillation of the axis of any rotating body. Positive displacement pumps are described in detail in co-owned U.S. application Ser. No. 10/955,175 filed on Sep. 30, 2004 under the title “Positive Displacement Pump” and its entire disclosure is hereby incorporated by reference wherever applicable. The depicted nutating pump is a direct drive, positive displacement pump used to move liquid from a starting point, in this case, the tube adapter171, to a destination, here, the mixing chamber184. The piston177is configured to rotate about its axis, so that its U-shaped depression180faces upward towards the tube adapter171to load the concentrate and faces downward towards the mixing chamber184at the end of one cycle to unload its content. Meanwhile, the piston177also oscillates back and forth in the direction indicted by the arrow204, providing additional positive forces to transfer the concentrate.

One advantage for employing positive displacement pumps such as a nutating pump or a valveless piston pump as opposed to progressive cavity pumps or peristaltic pumps is the enhanced immunity to wear or variation in concentrate viscosity. Prior art pumps often suffer from inconsistency in delivery due to machine wear or the need for a break-in period; they also face low viscosity limits because concentrates of higher viscosity requires greater power in those pumps. In contrast, positive displacement pumps can deliver, with consistency and without the need for speed adjustment, concentrate loads over a wide range of viscosities. Accordingly, to deliver a predetermined amount of concentrate, one only needs to set the pump speed once.

In one embodiment, the pump is equipped with an encoder to monitor the number of piston revolutions—e.g., each revolution may be equal to 1/32 of an ounce (about 0.0009 L) of the concentrate. The encoder may be placed on the rotary shaft of the pump motor to count the number of revolutions the piston has turned in relation to the water flow. The number of pump revolutions is dictated by the control system based on two pieces of information: a predetermined, desired mix ratio between the concentrate and the water, and the amount of water flow sensed by the flowmeter assembly described above.

Still referring toFIG. 10, optionally, the controller system may be programmed to ensure that the pump piston177is returned to the intake position at the end of each dispense operation. By having the piston positioned at the intake stroke with its U-shaped depression facing upward, the entry point to the mixing chamber184for the concentrate will be completely sealed to prevent any leakage of concentrate. This also allows water, which enters the mixing chamber184at the port206from the water delivery system78, to flush and clean the outlet of the pump and the mixing chamber184during and after each dispensing cycle.

Mixing and Dispensing System

The mixing and dispensing system76provides a common space for the concentrate and the diluent to meet and blend. The mixing and dispensing system76also includes parts that facilitate the blending. Referring back toFIG. 9, in one embodiment, the mixing and dispensing system76includes the mixing housing178and the mixing nozzle80. As described earlier, top portions of the mixing nozzle80fit into the mixing housing178and forms the mixing chamber184(FIG. 10) therebetween. In one embodiment, the mixing housing178is fabricated as part of the pump head172.

Referring now toFIG. 11, according to one feature of the invention, a barrier structure or diverter200on the nozzle top surface182faces an incoming diluent stream and forces the diluent to spray into an incoming concentrate stream being unloaded by the piston177. In an example where the diluent is water, the incoming water stream enters the mixing chamber through a lower plate opening198and then a water entry port206(FIG. 10) in the mixing chamber housing178(FIG. 10). The turbulence created by the redirected water flow continues through the entire dispensing cycle and effectively produces an evenly and thoroughly blended mixture of the concentrate and the water.

The mixture then flows through the opening202in the nozzle top surface182and passes through the rest of the mixing nozzle80before emerging out of the discharge outlet186(FIG. 9). In one embodiment, a mixture of concentrate and water is kept in the mixing chamber after dispensing a requested product for a “top off” operation.

FIGS. 13A,13B, and13C depict one embodiment of the mixing nozzle80according to the invention. A nozzle body189has an inlet section191, an outlet section195and a depressurizing section193in between. The nozzle body189extends along a rotational axis197, and defines a liquid passageway199from the inlet section191to the outlet section195. The inlet section191consists of a nozzle top261and the barrier structure or diverter200thereon. The depressurizing section193consists of a depressurizing chamber263in between the nozzle top261and a chamber floor264. The depressurizing chamber263may be partitioned, in part, by multiple walls266into multiple chambers. In each chamber, there is an elongated diffusion slot268on the chamber floor264near the floor's periphery. There can be any number, e.g., four, of these diffusion slots, and two of them, labeled268aand268b, are depicted in the drawings. Compared to the inlet opening202, these diffusion slots268are farther away from the nozzle axis197to direct the liquid flow towards the nozzle periphery.

Still referring toFIGS. 13A to 13C, the diffusion slots268lead into a funnel270(best viewed inFIG. 13C) defined by the nozzle outlet section195. A funnel, as used herein, refers to a structure that defines a passage where the cross section of one end is larger than the other; a funnel's diameter may continually taper toward one end, or the tapering may be interrupted by sections where the diameter is unchanged. In the illustrated embodiment, the funnel270includes an inner wall272that, from the top to bottom, have a constant diameter at first, and then continually tapers toward the edge274of the discharge outlet186.

Specifically referring toFIG. 13C, the nozzle's liquid passageway199begins at the inlet opening202on the nozzle top surface182. The nozzle top surface182serves as the floor of the mixing chamber when the nozzle body189is partly inserted in the mixing housing. While the nozzle top surface182can be flat, in a preferred embodiment, it is slightly curved with the inlet opening202at the lowest point of the floor to aid gravitational drainage. The initial portion of the nozzle passageway199is an inlet channel262of constant diameter that extends from the inlet opening202through the nozzle top261and into the depressurizing chamber263. In one embodiment, the inlet opening202is designed to be fairly restricted compared to the size of the nozzle top surface182, so that when the postmix product flows through the inlet channel262and enters the depressurizing chamber263, the substantial increase in the average cross-sectional area of the liquid passageway199greatly reduces the pressure and hence the momentum of the liquid flow. The pressure drop induced by the depressurizing chamber263serves to reduce splashing in dispensing the product. In one embodiment, the depressurizing chamber263has a cross-sectional area that is at least 20 times, preferably 50 times, and more preferably 100 times larger than that of the inlet channel262. In one embodiment, the inlet opening202has a diameter of 0.125 inches (about 3.2 mm) and the depressurizing chamber263has a diameter of 1.375 inches (about 3.5 cm), therefore an 121 times increase in cross-sectional area.

Both the nozzle top261and the chamber floor264have a groove around its periphery that each accommodates an o-ring276a/276b. The o-rings seal against the inside of the mixing housing when the nozzle body189is locked in.

Still referring toFIG. 13C, the last portion of the nozzle passageway199consists of the funnel270. The diffusion slots268that lead to the funnel can be of a variety of shapes, including oval, kidney bean-shaped, circular, rectangular, fan-shaped, arc-shaped and so on. The diffusion slots268are situated along the edge of the chamber floor264to direct the product flow toward the inner funnel wall272. As the product streams down the funnel wall272as opposed to free fall in the middle of the passageway199, splashing is further reduced. The increase in cross-sectional area of the flow path as it enters from the diffusion slots268into the funnel270also tend to slow down the flow. The shape of the funnel270as a large portion of it continually tapers down towards the bottom edge274also tends to create a spiral flow pattern as the flow is re-centered toward the nozzle axis197. A centered product stream makes it easier to receive the entire product in the waiting receptacle.

Sections of the nozzle body189as well as other distinct structures described herein may be fabricated separately and assembled before use, or, fabricated as one integrated piece. The nozzle body189should be sized such that at least the inlet section191and the depressurizing section193fit into a nozzle housing, e.g., the mixing housing178(FIG. 10). The nozzle may be manufactured in a variety of food-safe materials, including stainless steel, ceramics and plastics.

Referring back toFIGS. 13A,13B, and13C, the diverter200provides an elevated blocking surface201that redirects an incoming water stream. The diverter200is depicted as substantially cylindrical, but one skilled in the art understands that it can be of any of a variety of geometrical shapes. The blocking surface201is designed to maximize contact between water and the concentrate. In this case, it changes the direction of a pressurized water stream so that the water stream meets the incoming concentrate stream head on, i.e., the two streams meet at a degree close to 180 degrees, or at an obtuse angle. Referring back toFIG. 11, the blocking surface201creates a spray pattern as it redirects water so that water molecules bounce off the surface in a variety of directions as illustrated by arrows203aand203b. The incoming concentrate stream moves generally in the direction of gravitational fall as indicated by arrow205. The two streams meet at an angle207. In one embodiment, the angle207is more than 90 degrees, and preferably, more than 120 degrees.

The blocking surface201may be of a variety of geometry, even or uneven, uniform or sectioned. For example, the blocking surface201may be concave or convex, corrugated, dimpled, and so on. In the illustrated embodiment, the blocking surface201is a concave surface such that a wide, thin, powerful spray patter of diverted water is generated that cuts into the concentrate stream, and creates turbulent flow pattern inside the mixing chamber. This turbulent pattern results in a uniformly blended product that is then forced into the opening202on the nozzle top surface182. The edge of the blocking surface201may be sharp or blunt. In one embodiment, to avoid injury to the operator, the top of the diverter200is flattened or rounded.

To ensure that the blocking surface201substantially faces the water stream coming into the mixing chamber, i.e., that the nozzle body189is locked in a predetermined orientation inside the mixing chamber, certain locking features may be added to the nozzle. Referring toFIGS. 13B and 13C, in one embodiment, the blocking surface201is situated asymmetric about the nozzle axis197, therefore, a locking structure that is also asymmetric about the nozzle axis197is provided to orient the nozzle. In one embodiment, such locking structure includes an asymmetric collar that is integrated with the nozzle body189. Specifically, the asymmetric collar can be a D-shaped collar278situated between the chamber floor and a middle collar280, and having a flat side279. There is a locking groove282between the D-shaped collar278and the middle collar280that will engage an adapter panel as described hereinbelow. Both the D-shaped collar278and the middle collar280are preferably integrated with the rest of the nozzle body189.

Still referring toFIGS. 13B and 13C, another locking structure can be a set of projections that extend along the nozzle axis197. In one embodiment, the projections are a pair of wing-like handles284and286that occupy different latitudinal spans along the outside of the nozzle body189. The locking handle284extends from just below a lower collar288upward and terminates level to the top of the middle collar280. The regular handle286also extends from just below the lower collar288upward, but terminates below the top of the middle collar280.

The use of the locking structures and the installation of the mixing nozzle are now described. Referring now toFIGS. 14A and 14B, a corresponding locking structure that facilitates the installation and locking of the mixing nozzle is found in an adapter panel290. The adapter panel290, in one embodiment (FIG. 9), is fixedly situated behind the front door and underneath the mixing chamber184—its spatial relation to the water path is fixed and known. The adapter panel290defines one or more openings292sized and shaped to let through the asymmetric collar278but not the larger middle collar280of the nozzle body189(FIG. 13C). As depicted in the top view provided byFIG. 14A, in the particular embodiment where the asymmetric collar278is D-shaped, so is the adapter opening292.

Referring to the bottom view of the adapter panel290provided by FIG.14B, the D-shaped opening292is situated inside a largely circular recess such that the recess is a step-down from the rest of the panel290and the rim of the D-shaped opening292is surrounded by the recess floor294. The recess border296is sized and shaped to fit the middle nozzle collar280snugly. The recess has an arc-shaped locking slot298in addition to the circle that fits the middle nozzle collar280; the locking slot298is designed to dictate the locking and unlocking sequence in cooperation with the locking handle284(FIG. 13C). Specifically, the locking slot298is sized such that the top of the locking handle284fits snugly in the slot and can rotate back and forth between one side299of the slot and the other side300, rotating the rest of the nozzle body with it.

In operation, referring to bothFIGS. 13B and 14B, the nozzle inlet section191and the nozzle depressurizing section193are inserted from under the adapter panel290through the opening292. Because of their asymmetric shapes, the flat side279of the D-shaped collar278must align with the flat side297of the opening292. The middle nozzle collar280will not be able to go through the adapter opening292, but will rest inside the panel's recess border296against the recess floor294. At this point, the nozzle body189is at an unlocked position with the locking handle284rested against the “unlocked” side299of the locking slot298. The unlocked position is depicted inFIG. 15which shows the adapter panel290's recess floor294engaged inside the locking groove282between the nozzle D-shaped collar278and the nozzle middle collar280, and the locking handle284toward the very back of the mixing chamber184.

Referring back toFIGS. 13B and 14B, the orientation of the locking slot298dictates that the locking handle284can only rotate counterclockwise (note thatFIG. 14Bis a view from the bottom) until it is stopped at the “locked” side300of the locking slot298. The locked position is depicted inFIG. 16in which the elevated blocking surface201faces directly at the water stream entering from the direction of the opening198. To unlock the nozzle, simply reverse the above-described sequence of motion by turning the handles284and286clockwise until they stop at the unlocked position depicted inFIG. 15. The operator can then use the lower nozzle collar288as a gripping aide to pull the nozzle body189downward out of the opening292in the adapter panel290.

Control System

To monitor and control the operation of various systems inside the dispenser, a control system is provided. The control system may include a microprocessor, one or more printed circuit boards and other components well known in the industry for performing various computation and memory functions. In one embodiment, the control system maintains and regulates the functions of the refrigeration system, the diluent delivery system, the concentrate delivery system, and the mixing and dispensing system. More specifically, the control system, with regard to:refrigeration system: monitors filter placement, activates water chilling loop, supports water chilling loop over cabinet chilling loop;diluent delivery system: regulates one ore more gate-keeping switches that control the water flow at various points, regulates pressure of the water flow; receives and stores flow rate output;concentrate delivery system: monitors pump head lock, receives and stores information regarding the concentrate including desired mix ratio of the product, ascertains concentrate status, computes and regulates pump speed and fill volumes, controls piston position;mixing and dispensing system: activates cleaning of the system, dispenses the right fill volumes; anddiagnostics: identifies errors and provides correctional instructions.

The above outline is meant to provide general guidance and should not be viewed as strict delineation as the control system often works with more than one system to perform a particular function. In performing refrigeration-related functions, the control system, as described earlier, ensures that the refrigeration system cannot be energized if the filter is not properly installed. In that case, the control system may further provide a diagnostic message to be displayed reminding an operator to install the filter. The control system further monitors, through output signal from the flowmeter, the amount of water that has passed through the flowmeter, and allows the activation of the primary water chilling loop only after sufficient amount of water, e.g., 21 ounces (about 0.62 L), has passed to prevent freeze-up of the water circuit.

Once the primary water chilling loop has been activated, however, the control system will support its function over secondary cabinet chilling loop. The control system also ensures that only one refrigeration loop is energized at any given time, and that the cabinet chilling loop is energized when the cabinet is above a predetermined temperature.

The diluent delivery system may include gate-keeping switches such as solenoid valves at various points along the water route. The control system controls the operation of these switches to regulate water flow, e.g., in and out of water chilling loop, specifically, as water enters and exits the BPHX. The control system also regulates the pressure of the water flow, through pressure regulators, for instance. Output signals from the flowmeter are sent to the control system for processing and storage.

In each dispensing cycle, once a portion size has been requested, the control system determines when the request has been fulfilled by reading the water flow from the flowmeter and adding the volume dispensed from the concentrate pump. Each of the portions will be capable of being calibrated through a volumetric teach routine. Provisions to offset the portion volume for the addition of ice may be incorporated into the control scheme.

With regard to the concentrate delivery system, the control system ensures that no dispensing cycle starts if the pump head is not properly assembled through the locking ring, as described earlier. The control system, following the master-follower plan where water is the master and the concentrate is the follower, regulates the pump speed based on computed fill volumes and detected water flow rate to achieve a desired mix ratio. Unlike some of the prior art control mechanisms where both the concentrate flow and the diluent flow are actively regulated, the control scheme of the present invention only actively adjusts one parameter (pump speed), making the system more reliable, easier to service, and less prone to break-down. At the end of each dispensing cycle, the control system ensures that the piston in the concentrate pump is returned to the intake position so that a seal is effectively formed between the concentrate delivery system and the mixing and dispensing system.

Referring now toFIG. 17, to provide the control system with information regarding a package of concentrate as it is loaded into the dispensing system, the present invention provides a data input system. The system includes a label208aor208band a label reader210installed in the dispenser50. The label reader210may be an optical scanner, e.g., a laser scanner or a light-emitting diode (LED) scanner. In one embodiment, the label reader210is an Intermec® E1022 Scan Engine, commercially available from Intermec Technologies Corporation, housed behind a protective cover. In another embodiment, the data input system employs radio frequency identification (RFID) technology and the label reader210is a radio frequency sensor. The label208ais detachably affixed to the concentrate drainage tube72, which is preferably made of a pliable material, in the form of a tag, tape, sticker, chip, or a similar structure, while label208bis permanently associated with, e.g., directly printed onto, the concentrate drainage tube72. In one embodiment, the label208ais made of waterproof mylar and backed with adhesive. The label208aor208beach includes certain information in a machine-readable form212regarding the particular concentrate package that the label is associated with. The machine-readable form212may be optically, magnetically or electronically or otherwise readable. In one embodiment, the machine-readable form212is readable by radio frequency. The information may include: data on desired compositional ratio between the concentrate and the diluent in the postmix product, whether the product requires a low (product with ice) or high (product without ice) fill volume of the concentrate for any given portion size, the expiration date to ensure food safety, flavor identity of the concentrate, and so on. In a preferred embodiment, the label includes some unique information about each package, such that a unique and package-specific identifier can be generated. For example, the label may indicate when the concentrate was packaged up to the second, which would typically be unique for each package.

Referring now toFIG. 18, in an example of the label, the data is presented in a barcode that corresponds to the parameters represented graphically herein. Specifically, the first data set214represents the packaging date “Jan. 7, 2000.” The second data set216represents the packaging time in the format of “hour-minute-second” (the illustrated example uses a random integer of five digits). The third data set218represents an indicium for a desired compositional ratio between a diluent and the concentrate in the postmix product, as in this particular example, 5:1. The fourth data set220represents the expiration date of the package “Jan. 26, 2000.” The fifth data set222represents ice status, i.e., whether ice is typically added to the postmix product derived from this concentrate. The sixth data set224represents concentrate's flavor identity, in this case, “A” for orange juice. The control system is programmed to translate each data set into real information according to preset formulas.

Once the reader210obtains package-specific information from the label208aor208b, it sends the information to the control system. The control system is then able to display such information for the user, to regulate the mixing and dispensing of the product, to track the amount of remaining concentrate, and to monitor freshness of the concentrate to ensure safe consumption.

Referring now toFIG. 19, operational steps related to the data input system are illustrated. In step226, a concentrate holder with an empty or expired concentrate package is removed from the concentrate cabinet. In step228, it is then determined which side of the dispenser was the holder removed from or otherwise emptied. An internal flag is set for the control regarding the empty/out status. This can be accomplished through a variety of ways. For example, the machine may have a sensor that monitors the position of the concentrate holder, or the machine can be manually taught which side the concentrate holder was removed from. In one embodiment, a magnet is embedded in the concentrate holder (e.g., at the bottom) such that removal the holder triggers a reed switch at a corresponding position inside the dispenser to signal the removal to the control system.

Still referring toFIG. 19, once the control learns that a concentrate holder has been removed from the dispenser, in step230, it actuates the label readers e.g., an optical scanner, and in step232, turns on indicators for the affected side, e.g., a red and amber LED. In step234, an operator refills the holder with a new concentrate package and places the holder back into dispenser. In step236, the operator manually presents a new label on the new drainage tube for the activated scanner and scans the barcode. Alternatively, the label is automatically detected and read by a sensor or reader in the dispenser. In step238, the control determines if the scan is successful. If not, it will direct the operator to rescan the barcode in step240. If the scan is successful, however, the scanner will power off and a unique product identifier is generated by the control in step242. This unique identifier, specific for each concentrate package, is kept in a registry on the control as a permanent record to prevent product tempering.

Because the control system regulates the pump speed and the pump delivers a set amount of concentrate through each revolution, the control system can monitor the amount of concentrate dispensed from a particular package at any given time and assign the information to the unique identifier. Accordingly, the control system can compute and display the theoretical volume left in a given package or to alert the operator when the concentrate is running low. Once the package is emptied out, the control will flag the associated identifier with a null status and not allow the package to be reinstalled. The unique product identifier will also be used by the control system to track how many times the package associated with it has been installed, and to continually monitor concentrate usage throughout the life of the package. If a package is removed from the dispenser prior to being completely used, the control will recognize the same package when it is reinstalled in the dispenser and will begin counting down the volume from the last recorded level.

Referring again toFIG. 19, the unique identifier is used to monitor and regulate other aspects of concentrate usage. For example, in step244, the control determines if the concentrate has expired or passed the best-used-by date. In step246, if the answer is affirmative, the control will flag that product identifier and disallow any further dispensing from the current package. In the next step248, a warning signal is indicated, e.g., through two red LEDs. The control also reactivates the scanner and the sequence reverts to step234to start replacing the package. If it is determined that the concentrate has not expired in step244, however, the control continues to determine if the barcode is still valid in step250. If the answer is negative, step248and subsequent steps are initiated. If the answer is affirmative, step252is initiated where information on desired compositional ratio setting and previously obtained from scanning the package label is processed. In step254, the control further determines, also from scanned information on the label, whether ice is normally required in the postmix product.

Based on information gathered in steps252and254, the control computes the volume of the concentrate needed for each portion size requested by the operator. In step256, default fill volumes are used for all portion sizes when it is indicated that no ice is needed for the postmix product. Otherwise, as in step258, fill volumes are offset by a predetermined value if need for ice is indicated. In either case, the control proceeds to step260to update the dispenser display with the appropriate flavor identity, also obtained from the scanning of the label in step236.

According to one feature of the invention, the control system is programmed and configured to regulate the mixing and dispensing process to achieve consistency in compositional ratio, e.g., between about 10:1 to about 2:1 for the ratio between the diluent and the concentrate. The control system needs two pieces of information to accomplish this task: desired compositional ratio and the flow rate of the diluent. The former can be obtained, as described above, through the data input system where a label provides the information to the control. The latter is received as an output signal generated by a metering device, e.g., a flowmeter, that is in electrical communication with the control circuit. In addition to set the rate of concentrate delivery, the control system, further based on portion size information, i.e., the specific portion size requested and whether ice is needed in the postmix product—this last information preferably also comes from a package label—decides on the duration of a dispensing cycle.

In an embodiment where a positive displacement pump, e.g., a nutating pump, is used to pump the concentrate into contact with the diluent to form a mixture, the motor is configured to actuate the nutating pump, and the amount of concentrate transferred by each motor revolution is fixed. Accordingly, encoder can be configured to regulate a rotary speed of the motor, and hence, the rate of concentrate transfer. The control system, in electrical communication with the encoder, sends a command to the encoder once it has computed a desired rotary speed and/or duration for a given dispensing cycle. Accordingly, the right amount/volume of the concentrate is added to each dispensing cycle.

For example, the control receives, from the package label, the desired compositional ratio between the water and the concentrate as 10:1. Further, the flowmeter signals the control that water is flowing at a rate of about 4 ounces (about 0.12 L) per second. That means the concentrate needs to be pumped at a rate of about 0.4 ounce (about 0.012 L) per second. Since each revolution of the pump piston always delivers 1/32 ounce (about 0.0009 L) of the concentrate, the control sets the piston to run at 12.8 revolutions per second. If a portion size of 21 ounces (about 0.62 L) is requested for a dispensing cycle and no ice is needed in the product according to the package label, the control will determine that the dispensing cycle should last for about 4.8 seconds.

Further, the control system can adjust the pump's motor speed. The encoder sends a feedback signal in relation to a current rotary speed to the control, and the control, in turn, sends back an adjustment signal based on the desired compositional ratio, and the water flow rate detected by the flowmeter. This is needed when water flow rate fluctuates, e.g., when a water supply is shared by multiple pieces of equipment. This is also necessary when the desired compositional ratio in the postmix product needs to be adjusted as opposed to have a fixed value. A preferred embodiment of the control system automatically adjusts the pump speed to ensure the desired compositional ratio is always provided in the postmix product.

Each of the patent documents and publications disclosed hereinabove is incorporated by reference herein for all purposes.

While the invention has been described with certain embodiments so that aspects thereof may be more fully understood and appreciated, it is not intended to limit the invention to these particular embodiments. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the scope of the invention as defined by the appended claims.