Field-installable refrigerated cabinet kit, refrigerated vending machine, and instructions for use

Abstract

The refrigerated enclosure or display device includes a pressure relief valve within the insulated wall of the evaporator enclosure and a frosting chamber between the pressure relief valve and the evaporator assembly. The pressure relief valve is heated to prevent frost from forming on the valve. The frosting chamber can be defined by a baffle that directs air entering through the pressure relief valve and along the evaporator. As outside air enters through the valve, moisture forms as frost on the walls of the frosting chamber and on the evaporator. During periodic defrost cycles, the frost can be removed by a defrost heater and condensate removal system. The pressure relief system can be installed in individual refrigeration system modules of a modular vending machine kit, automatically providing the required amount of pressure relief capacity during on-site installation.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Patent Application No. 17 / 878,625, filed August 1, 2022, which is incorporated by reference in its entirety.

[0002] The present disclosure generally relates to refrigerated vending machines and to refrigerated cabinet kits that include one or more field-installable refrigeration system modules configured to be removably and operably mounted and attached to a cabinet module to form a refrigerated vending machine. [Background technology]

[0003] Reach-in refrigerated cabinets have an access door and are used to store and / or display refrigerated goods. One known type of refrigerated reach-in cabinet is a display refrigerated vending machine. Traditionally, there are two types of refrigerated vending machines: built-in and remote refrigeration. U.S. Department of Energy regulations distinguish between built-in and remote refrigeration systems. For example, energy consumption regulations for built-in refrigeration systems are based on measurements of the machine's energy consumption, while energy consumption regulations for remote refrigeration systems are based on estimated calculations of refrigerant mass flow and electrical load.

[0004] A self-contained vending machine is a prefabricated assembly that includes a cabinet with an integrated refrigeration system. In many self-contained vending machines, the refrigeration system is sealed to prevent refrigerant loss through access valves or mechanical joints. The refrigeration system in a self-contained vending machine is precisely designed for the application and applicable regulations, taking into account the cabinet's size, load, and temperature requirements. Adhering to these constraints allows self-contained vending machines to operate extremely efficiently compared to remotely refrigerated vending machines (described below). Self-contained vending machines can utilize on-board systems to remove condensation that builds on the refrigeration system, which does not have a separate drain connection. Air-cooled self-contained vending machines require only a single cord-and-plug electrical connection to operate. Water-cooled self-contained vending machines require only a single cord-and-plug electrical connection and running water to remove heat from the condenser. This makes self-contained vending machines a preferred option for retailers that rent buildings or who may need to move refrigerated cabinets around the building.

[0005] In contrast, remotely refrigerated vending machines are typically built into the retailer's building during installation. Most typically, a refrigeration system for multiple remote vending machine cabinets is mounted on the building's roof, with the vending machine cabinets installed as interior fixtures and physically separated from the remote refrigeration system components by the building's roof. The HVAC contractor must create a refrigeration connection between the evaporator mounted inside the cabinet and a piping trench that connects the vending machine to a remote condenser, typically located on the building's roof. (Not all remote refrigeration systems are located on the roof; some have a mechanical room to house them.) Additionally, to handle condensation that forms on the evaporator during use, a plumber must create a drain connection between the cabinet's condensate removal line and the building's drain line, which usually runs through a trench below the cabinet floor. In some cases, hoses and pumps can be used to route the condensate to a heated drain pan. Because remote refrigeration is a fixed fixture, an electrician ultimately provides the electrical connections. Thus, remote refrigerated vending machines are best suited for retailers who own or lease retail buildings for very long periods of time, since they require trenches to be dug in the floor to route refrigerant lines, drainage, and electrical cables. In addition to the inherent immobility of remote refrigerated vending machines, another drawback of remote refrigeration systems compared to self-contained vending machines is operational efficiency. To ensure the necessary refrigeration capacity is always available, the refrigeration system, typically mounted on the building's roof or at a remote location, is typically larger than the actual refrigeration requirements of the cabinets installed within the building. In other words, remote refrigeration systems lack application-specific design for their internal components, due to the proximity of the refrigeration system's dimensions. Remote systems must account for seasonal fluctuations in outdoor temperatures and the need to operate multiple cabinets for different products (freezers, refrigerators, floral coolers, etc.) from the same refrigeration system, sized for worst-case conditions. In this way, each cabinet consumes its required amount of refrigeration from a hypothetical endless source. Furthermore, because all refrigeration, plumbing, and electrical connections must be made on-site, remote refrigerated vending machines are never sealed and are more susceptible to water and refrigerant leaks.Refrigerant leaks are extremely harmful to the environment and again result in installation costs.

[0006] The advantage that remote refrigerated vending machines have over self-contained vending machines is greater "fill capacity," which is the available space inside the machine to hold vendible goods. A typical self-contained vending machine with the same footprint has less fill capacity due to the inclusion of the condenser and compressor portions of the refrigeration circuit.

[0007] Remote refrigeration cabinets are often installed during building construction (or conversion for a specific purpose), with the cabinets often being loaded into the building by crane before the roof is installed. In contrast, self-contained vending machine cabinets must be able to fit through standard human-height doorway openings (e.g., doorways no higher than 8 feet, e.g., doorways no higher than 7 feet, or doorways approximately 82 inches high) for their intended use. Furthermore, in remotely refrigerated vending machines, many of the major mechanical components of the refrigeration system are remotely located, minimizing the space occupied by the refrigeration elements inside the building. In contrast, existing self-contained vending machines must physically house and support all refrigeration system components within the component area. This area must also be adapted to fit through a standard human-height doorway.

[0008] To increase the loading capacity of vending machines that are at least somewhat portable and can be installed through standard-height doorways, a third type of vending machine has recently become available that combines aspects of built-in and remote refrigeration machines. This third type of vending machine does not yet have an industry-standard name or definition. However, this type essentially consists of two separate modules that can be assembled on-site as a kit. The first module is a cabinet module sized to fit through a standard-height doorway, and the second module is a refrigeration system module that also fits through a standard-height doorway. Furthermore, the refrigeration system module is configured to be attached to the cabinet module after both modules are delivered to the building. Thus, the third type of vending machine includes a field-installable refrigeration system configured to be supported on the cabinet. Examples of field-installable, self-supporting vending machines are the Hybrid Showcase sold by Zero Zone and the Freedom vending machine sold by Hussmann. In these systems, the cabinet module includes the evaporator unit, and the condensing unit is initially provided as a separate module from the cabinet module. Field-installed mechanical refrigeration connections are made on-site by a licensed refrigeration engineer between the condensing unit and the evaporator within the cabinet module.

[0009] In large-volume vending machines, pressure differences between the inside and outside of the cabinet can cause problems for users. When a user opens the machine's door, warm air rushes into the cabinet. When the door is closed, the temperature of the warm air drops rapidly, causing a corresponding drop in pressure. In a tightly sealed cabinet, this creates a pressure difference between the inside and outside of the cabinet. In large-volume machines, this creates a vacuum effect on the door, making it very difficult to open. Various methods have been proposed in the past to address this problem. For example, some have incorporated door handle mechanisms that break the door seal when a user attempts to open the door. More commonly, other proposals have involved incorporating pressure relief valve systems into refrigerated cabinets, which act passively by opening in response to increased pressure differences, automatically equalizing the pressure inside and outside the cabinet. Summary of the Invention [Means for solving the problem]

[0010] In one aspect, a field-installable refrigerated vending machine kit includes a cabinet module having an exterior and an interior. An off-the-shelf refrigeration system module is configured to operably connect to the cabinet module to cool the interior. The off-the-shelf refrigeration system module is separate from the cabinet module. The off-the-shelf refrigeration system module and the cabinet module include interconnect fittings configured to removably and operably connect the off-the-shelf refrigeration system module to the cabinet module to cool the interior of the cabinet module. The off-the-shelf refrigeration system module includes a pressure relief valve configured to automatically open in response to pressure inside the cabinet module being lower than pressure outside the cabinet module, whereby the pressure relief valve is configured to equalize pressure between the interior and exterior of the cabinet module.

[0011] In another aspect, a method for providing a refrigerated storage cabinet with sufficient pressure equalization capacity to equalize pressure between an interior and an exterior of the refrigerated storage cabinet includes providing the refrigerated storage cabinet with a plurality of pairs of supply air inlets and return air outlets. A plurality of cooling systems are provided that are configured to operably connect to the refrigerated storage cabinet to cool the interior. Each pre-fabricated cooling system includes a pressure relief valve configured to automatically open in response to a pressure differential across the pressure relief valve. Each of the plurality of cooling systems is attached to the refrigerated storage cabinet such that each cooling system is configured to cool the refrigerated storage cabinet by applying chilled air within the cabinet and drawing return air from the cabinet, and such that each pressure relief valve is configured to open in response to pressure within the refrigerated storage cabinet being lower than pressure outside the refrigerated storage cabinet, whereby the pressure relief valves of the plurality of cooling systems equalize pressure within the refrigerated storage cabinet with pressure outside the refrigerated storage cabinet.

[0012] In another aspect, a refrigerated storage or display device includes a cabinet having an interior and an exterior. The evaporator enclosure includes an insulating wall separating the interior of the evaporator enclosure from the exterior. The insulating wall defines a pressure relief valve opening. A refrigeration system for cooling the interior of the cabinet includes an evaporator assembly within the evaporator enclosure. A frosting chamber within the evaporator enclosure between the insulating wall and the evaporator assembly has a cooled interior frosting surface. The frosting chamber is immediately adjacent to the evaporator assembly such that the frosting chamber is cooled by the evaporator assembly. An evaporator drain pan is below the evaporator assembly and the frosting chamber. A pressure relief valve within the pressure relief valve opening includes a valve heater configured to heat the pressure relief valve to prevent frost from forming within the pressure relief valve. The pressure relief valve is configured to open in response to the pressure inside the cabinet being lower than the pressure outside the cabinet, thereby introducing moisture-laden outside air through the pressure relief valve into the cooling system and then into the interior of the cabinet until the pressure inside the cabinet equalizes with the pressure outside the cabinet. The pressure relief valve is configured to direct the outside air into the interior of the cabinet through the frosting chamber, thereby causing moisture in the outside air introduced through the pressure relief valve to freeze as frost on the cooled interior frosting surface of the frosting chamber. The defrost heater is configured to periodically perform a defrost cycle in which the defrost heater defrosts the evaporator. The frosting chamber is positioned relative to the defrost heater so that frost formed on the cooled interior frosting surface during the defrost cycle is defrosted and discharged to the evaporator drain pan.

[0013] In another aspect, a refrigerated storage or display device includes a cabinet having an interior and an exterior. A cooling system for cooling the interior of the cabinet includes an evaporator and an evaporator fan configured to move air in the cabinet in a flow direction across the evaporator. A pressure relief valve is configured to open in response to a pressure inside the cabinet being lower than a pressure outside the cabinet, thereby introducing moisture-laden outside air through the pressure relief valve to the cooling system and then into the interior of the cabinet until the pressure inside the cabinet equalizes with the pressure outside the cabinet. A baffle between the pressure relief valve and the evaporator is cooled by the evaporator. The baffle is configured to redirect air entering the refrigerated storage or display device such that the air entering the refrigerated storage or display device flows along the baffle in a direction different from the flow direction before flowing in the flow direction across the evaporator.

[0014] Other aspects and features will become apparent below. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view of a field-installable refrigerated vending machine kit including a cabinet module and a separate refrigeration system module. [Figure 1A] 1. FIG. 4 is a perspective view similar to FIG. 1 showing another modular configuration of the field-installable refrigerated vending machine kit. [Figure 1B] FIG. 2 is a perspective view similar to FIG. 1 illustrating yet another modular configuration of a field-installable refrigerated vending machine kit. [Figure 2] FIG. 2 is a perspective view showing a refrigerated vending machine to which the kit of FIG. 1 is assembled. [Figure 2A] 1B is a perspective view showing a refrigerated vending machine to which the kit of FIG. 1A is assembled. FIG. [Figure 2B] FIG. 1C is a perspective view showing a refrigerated vending machine to which the kit of FIG. 1B is assembled. [Figure 3] FIG. 1 is a perspective view of a refrigerated vending machine with the cover removed. [Figure 4]FIG. 2 is a perspective view showing a cabinet module. [Figure 5] FIG. 2 is a cross-sectional view of the cabinet module in the front-to-back plane. [Figure 6] FIG. 2 is a cross-sectional perspective view of the cabinet module. [Figure 7] FIG. 2 is a perspective view of a cooling system module. [Figure 8] FIG. 1 is a top view of the cooling system module with the evaporator enclosure lid removed. [Figure 9] 9 is a cross-sectional view taken along the plane of line 9-9 in FIG. 8. [Figure 10] FIG. 2 is a bottom perspective view of the cooling system module. [Figure 11] FIG. 1 is a perspective view illustrating an assembly of a cooling system module including a base plate, an evaporator enclosure, and a pair of support rails. [Figure 12] FIG. 2 is a cross-sectional view of the refrigerated vending machine in the front-to-back plane. [Figure 12A] This is a cross section similar to that of Figure 12, with a cross section of the free refrigerated space inside the refrigerated vending machine superimposed. [Figure 12B] 13 is a cross section similar to FIG. 12, showing a cross section of the shelf space within a refrigerated vending machine superimposed thereon. [Figure 13] FIG. 13 is an enlarged view showing a part of FIG. [Figure 14] 14 is a cross-sectional view taken along the plane of line 14-14 in FIG. 11. [Figure 15] FIG. 12 is an exploded perspective view of the assembly of FIG. 11. [Figure 16] FIG. 1 is a front view of the cooling system module showing the rails located underneath. [Figure 16A] FIG. 10 is an enlarged perspective view of a portion of the cooling system module showing one of the rails located underneath. [Figure 16B] 16B is an enlarged perspective view similar to FIG. 16A showing a first screw mounted to the rail for temporarily holding the cooling system module in place. [Figure 17]FIG. 17 is a front view of the cooling system module similar to FIG. 16, but showing the rails in a raised position. [Figure 17A] FIG. 1 is an enlarged perspective view of a portion of the cooling system module showing one of the rails in a raised position. [Figure 17B] 17B is an enlarged perspective view similar to FIG. 17A showing a set of screws mounted on the rails to hold the cooling system module in place on the cabinet module. [Figure 18] FIG. 1 is a perspective view showing one of the rails. [Figure 19] FIG. 1 is a perspective view of a cooling system module with some parts removed to show a condensate heater. [Figure 20] 13 is a cross-sectional view similar to FIG. 12 showing the vending machine in an installed and operating position in the wall of a retailer's premises. [Figure 21] FIG. 1 is an enlarged perspective view of the refrigerated vending machine showing one side of the main electrical box. [Figure 22] FIG. 10 is an enlarged perspective view of the refrigerated vending machine showing the other side of the main electrical box. [Figure 23] FIG. 1 is a partial enlarged perspective view of the refrigerated vending machine showing the system's dedicated electrical box. [Figure 24] FIG. 1 is a schematic wiring diagram of a refrigerated vending machine. [Figure 25] FIG. 10 is a perspective view of another embodiment of a refrigeration system module that may be used in a refrigerated vending machine according to the present disclosure. [Figure 26] FIG. 26 is an elevational view of the cooling system module of FIG. 25. [Figure 27] 27 is a cross section taken in the plane of line 27-27 of FIG. [Figure 28] FIG. 28 is an enlarged view of a portion of FIG. 27. [Figure 29] 29 is a cross section taken in the plane of line 29-29 of FIG. [Figure 30] FIG. 30 is an enlarged view of a portion of FIG. 29. [Figure 31] FIG. 26 is a perspective view of a subassembly of the cooling system module of FIG. 25 including the frosting chamber. [Figure 32]FIG. 32 is a top view of the subassembly of FIG. 31. [Figure 33] FIG. 32 is another perspective view of the subassembly of FIG. 31. DETAILED DESCRIPTION OF THE INVENTION

[0016] Corresponding reference characters indicate corresponding parts throughout the drawings.

[0017] The inventors have recognized several drawbacks to existing refrigerated vending machines with field-installable cabinet-mounted refrigeration systems. In particular, each existing product of this type requires a portion of the refrigeration system to be housed inside the cabinet. This reduces storage capacity and makes inspection and repair of the refrigeration system difficult. In particular, service technicians must frequently access at least a portion of the refrigeration system from inside the refrigerator to complete repairs. This requires retailers to remove the contents of the vending machine before inspection, effectively disrupting retail operations. In addition, all existing field-installable cabinet-mounted vending machines require on-site plumbing connections to be made to deal with condensate by-products during refrigeration. Most typically, technicians must install a water pump and water lines along the back of the cabinet to pump condensate from a condensate pan located below the cabinet to an evaporator tray at the top of the cabinet. Field-installed piping is subject to leaks and also requires the cabinet to be located away from walls to leave space for the conduit and piping. Available height is also reduced by the condensate pan and pump traditionally located below the cabinet.

[0018] 1-1B, in one aspect, the present disclosure relates to a field-installable refrigerated cabinet “kit,” generally designated 10. The illustrated vending machine kit 10 includes a cabinet module 11 and one or more separate refrigeration system modules 12 configured to be installed in the cabinet module on-site (i.e., at the location of end use, rather than at a separate factory or manufacturing location). The term “kit” is used in this disclosure to refer to a set of separate parts that are intended to be combined into a larger assembly. For example, the cabinet module 11 and each refrigeration system module 12 are separate parts of the kit 10 that can be combined to form the refrigerated vending machine 10′ shown in FIG. 2. In certain embodiments, the kit may include instructions for combining the separate parts of the kit to form a refrigerated cabinet.

[0019] Providing a refrigerated vending machine as a field-installable kit instead of a prefabricated, all-in-one, self-contained refrigeration cabinet allows for larger cabinets and greater loading volumes than conventional self-contained vending machines, while still allowing the vending machine to be loaded through standard-height doorways. Accordingly, in one or more embodiments, each cabinet module 11 and each prefabricated refrigeration system module 12 is configured to fit upright through standard-height doorway doors having a height of 8 feet or less (e.g., doorways up to 7 feet or approximately 82 inches high). To maximize loading depth, in certain circumstances, it may be desirable to design the cabinet module 11 to be too large to fit through a single-door doorway of 36 inches or less. In other words, a double-door doorway of human height may be required to load the cabinet module 11 of certain embodiments into a building. However, within the scope of this disclosure, it is expressly contemplated that the cabinet module is designed and configurable to fit through a single-door doorway of human height having a height of 7 feet or less and a width of 36 inches or less.

[0020] 2-2B, the present disclosure relates to a refrigerated vending machine 10′ (broadly, a refrigerated reach-in cabinet) that includes one or more field-installable, cabinet-mounted refrigeration system modules 12. As described in further detail below, the illustrated vending machine 10′ addresses several shortcomings of existing vending machines equipped with field-installable, cabinet-mounted refrigeration systems. For example, in one or more embodiments, the illustrated vending machine 10′ is configured such that each refrigeration system module 12 is installable without any components of the refrigeration system protruding into the cabinet interior. Furthermore, each refrigeration system module 12 provides a fully enclosed refrigeration system (or, more broadly, a pre-assembled refrigeration circuit) that can be installed without making any refrigeration connections on-site. Furthermore, in certain embodiments, each illustrated refrigeration system module 12 includes an integrated condensate removal system, eliminating the need for additional conduit or piping connections. Indeed, the vending machine can be installed through a standard-height door without the need for skilled tradespeople, such as plumbers, HVAC technicians, or electricians. Moreover, because the vending machine 10' can be installed without piping along the back of the cabinet, the vending machine can be installed closer to the back wall (broadly speaking, the support structure) (e.g., at zero offset), providing a greater percentage of the vending machine's footprint usable commercial space. Furthermore, because no refrigeration system protrudes into the interior of the cabinet upon installation, the vending machine 10' can therefore be inspected or repaired after installation without entering the refrigerated space.

[0021] In the illustrated embodiment, the kit 10 is configured to provide a refrigerated vending machine 10'. However, it is contemplated that the kit may be used to form other types of refrigerated cabinets without departing from the scope of the present disclosure. For example, aspects of the present disclosure are particularly well-suited for upright refrigerated type refrigerated cabinets, including vending machines with doors or air curtains and vending machines using air- or water-cooled cooling systems.

[0022] Referring to Figures 3-6, the illustrated cabinet module 11 generally includes a set of insulating walls separating the interior and exterior of the cabinet. When each refrigeration system module 12 is installed in the cabinet module 11, a portion of the cabinet's interior defines a free refrigerated space. Figure 12A shows a cross-section of the free refrigerated space FRS within the illustrated cabinet module 11. Throughout this disclosure, the term "free refrigerated space" defines the refrigeration area in which refrigerated items can be held or through which a user of the vending machine 10 can reach the interior of the cabinet module 11. In this disclosure, "free refrigerated space" excludes areas that can be cooled by the refrigeration system but are occupied by air ducts and refrigeration system equipment. The term "free refrigerated space" thus defines the available space within the unit. In the general case shown in the drawings, the free refrigerated space includes all shelf space (for comparison, a cross-section of shelf space SS is shown in Figure 12B) and additional space, including the free (refrigerated) space between the leading edge of the shelf and the cabinet door 22. Support articles, such as shelves 24, used to support refrigerated items are part of the free refrigerated space and need not be excluded from the free refrigerated space, as is the treatment of piping and refrigeration system components in this disclosure. It will be appreciated that while the portion of the interior of cabinet module 11 occupied by refrigeration system components or piping is non-packable and cannot be used to store or display merchandise, the remaining shelf space and free refrigerated space is packable and usable for commercial purposes, and therefore forms available free refrigerated space for the vending machine.

[0023] 4-6 , cabinet module 11 includes a pair of side walls 14, a rear wall 16, a top wall 18, a bottom wall 20, and a kick plate 21. Side walls 14 define the interior sides (spaced apart along the width of the cabinet), top wall 18 defines the interior's top edge, bottom wall 20 defines the interior's bottom edge, and rear wall 16 defines the interior's rear. In the illustrated embodiment, the front of the cabinet's interior is defined by a pair of French doors 22. Preferably, each door 22 has a width of approximately 24 inches or approximately 30 inches, although other door widths are also possible. It will be apparent that cabinet modules having other numbers of doors (e.g., one or more doors) and other door configurations (e.g., sliding doors, doors hinged on the same side) may be used without departing from the scope of the present disclosure. It is also contemplated that one or more embodiments within the scope of the present disclosure may be implemented in an air curtain-type vending machine with an open front and no doors. In embodiments with multiple doors 22 as shown, each cabinet module 11 preferably includes a door sensor circuit 140 (shown generally in FIG. 24) that includes a door sensor for each door configured to output a signal indicating when the door is open.

[0024] The illustrated cabinet modules 11 are configured to form a reach-in cabinet. Those skilled in the art will recognize that a reach-in cabinet holds merchandise so that all merchandise is accessible to a user at a station at the front of the cabinet. In a typical reach-in cabinet, an able-bodied user of average build can reach items stored at the rear end of the free refrigerated space.

[0025] 1-1B and 2-2B, it can be seen that each refrigerated vending machine kit 10 within the present disclosure is modular, allowing for different configurations of cabinet module 11 and prefabricated refrigeration system module 12 to be selected to suit a particular application. As shown in FIG. 1A, some field-installable refrigerated vending machine kits 10 may use only a single prefabricated refrigeration system module 12 (see also FIG. 2A), while other modular configurations of field-installable refrigerated vending machine kits of the present disclosure may utilize multiple refrigeration system modules (see FIGS. 1 and 2, and FIGS. 1B and 2B). Thus, any given kit 10 may be just one of multiple selectable module kit options using interchangeable cabinet modules 11 and refrigeration system modules 12 to suit a particular application. Thus, in one aspect, the present disclosure contemplates a system of selectable modular refrigerated cabinet kits. These selectable modular refrigerated cabinet kits include multiple selectable cabinet modules 11 with different widths, door configurations, and sidewall configurations (e.g., sidewall configurations that allow refrigerated vending machines to be arranged in series), and multiple cooling system modules 12 with different refrigeration characteristics, which can be combined in different ways to meet the requirements of various applications.

[0026] A particular embodiment of a field-installable refrigerated vending machine kit 10 and corresponding vending machine 10' will now be described, as shown in Figures 1, 2, and 3-24. The particular modular configuration chosen for illustrative purposes only includes a two-door cabinet module 11 and two prefabricated refrigeration system modules 12. However, it should be understood that this particular modular configuration was chosen solely for illustrative purposes. A wide variety of other modular configurations of field-installable refrigerated vending machine kits and vending machines are contemplated within the scope of this disclosure.

[0027] Cabinet module 11 may include various internal product supports without departing from the scope of this disclosure. In the illustrated embodiment, vertically spaced shelves 24 are supported in cabinet module 11 to hold merchandise for sale. However, other product support / display configurations are possible. For example, in certain embodiments, merchandise for sale or other refrigerated items may be supported on roll-in carts (not shown) within the free refrigerated space. As described in more detail below, this is possible because the illustrated cabinet module 11 is configured to support the entire refrigeration system on top cabinet wall 18. No part of the refrigeration system is located at the lower end of the free refrigerated space. Thus, in one or more embodiments, the bottom wall 20 of the cabinet module is removed or lowered approximately flush with the ground, allowing the free refrigerated space to expand to approximately ground level. This allows a merchandise cart to roll into the free refrigerated space at ground level.

[0028] In the illustrated embodiment, the cabinet module 11 includes a plurality of adjustable support assemblies on the bottom wall 20 for adjusting the cabinet so that it is level. These support assemblies are described in more detail in U.S. Patent Application No. 17 / 031,129, filed September 24, 2020, and U.S. Patent Application No. 17 / 480,827, filed September 21, 2021, the entire contents of which are incorporated herein by reference. The cabinet modules may be supported in other manners without departing from the scope of this disclosure.

[0029] In a typical embodiment, the cabinet module 11 includes one or more integrated cabinet systems suitable for the requirements of a particular vending machine. For example, such cabinet systems may include one or more lighting systems 142 (schematically shown in FIG. 24 ) or one or more cabinet heating systems 144 (schematically shown in FIG. 24 ). Those skilled in the art will appreciate that heaters may be selectively used in refrigerated cabinets in certain commercial refrigeration elements, such as door midframe heaters, door glass heaters, and cabinet frame heaters. Such heaters may be used in heating system 144 in accordance with the present disclosure. In a typical embodiment, the cabinet module 11 further includes a heating pressure relief valve 145 (schematically shown in FIG. 24 ) configured to open in response to a pressure differential between the interior and exterior of the cabinet, thereby automatically equalizing pressure between the interior and exterior of the cabinet. Those skilled in the art will appreciate that the heating pressure relief valve 145 can reduce the pressure inside the cabinet 11 to a level lower than the pressure outside the cabinet, making it more difficult to open the door 22. By equalizing the pressure between the interior and exterior of the cabinet 11, the user can easily open the door even after a large temperature drop has occurred within the cabinet with the door closed.

[0030] In the illustrated embodiment, the cabinet module 11 is configured for a top-loading refrigeration system. However, the present disclosure is not strictly limited to a top-loading system. It is contemplated that the refrigeration system modules can be mounted on the side, bottom, or rear of the vending machine, depending on customer / application needs. However, again, in the illustrated embodiment, each refrigeration system module 12 is mountable to the top wall 18 to cool the free refrigerated space of the cabinet 11. A top shroud 26 may be mounted along the edge of the top wall 18 above the door 22 to conceal the refrigeration system modules 12, provide access to controls, and / or add lighting or other business imagery as desired. Preferably, the shroud 26 is a separate component of the refrigerated vending machine kit 10 that is configured to be field-mounted to the cabinet module 11. This maximizes the height of the free refrigerated space while also allowing the cabinet module to pass through a door the height of a standard person.

[0031] The top wall 18 of the cabinet module 11 is generally configured to operably connect to one or more respective cooling system modules 12, enabling each cooling system module to cool the interior of the cabinet. In the illustrated embodiment, the top wall 18 of the cabinet module 11 includes separate inlet and outlet ports 30, 32 for each cooling system module 12. The inlet ports 30 are configured to provide cool air from each cooling system module 12 to the cabinet interior, and the outlet ports 32 are configured to return warm air, which carries heat and moisture to the products, to each cooling system module. In the illustrated embodiment, each supply air inlet 30 comprises an elongated slot extending widthwise of the cabinet and penetrating the depth of the top wall 18 adjacent to the rear wall 16. Each return air outlet 32 similarly comprises an elongated slot extending widthwise and penetrating the depth of the top wall 18. Each return air outlet 32 is spaced forward and backward from the front of its corresponding supply air inlet 30. The inlet and outlet ports 30, 32 shown in this embodiment define the cold and hot air passages. In some applications, it is envisioned that these ports may be reversed, with cold air supplied through the front duct and hot air supplied through the rear duct.

[0032] The top wall 18 further includes one or more integrated fittings for removably and operably attaching one or more cooling system modules 12 to the cabinet module 11. In particular, the illustrated top wall 18 includes a plurality of pre-formed holes 34 (e.g., threaded holes) configured to receive removable fasteners (e.g., screws) (as described in more detail below) that operably connect each cooling system module 12 to the cabinet module 11. In one or more embodiments, for each cooling system module 12, the threaded holes 34 include a first set of screws spaced apart in a first front-to-back row located on a first side of the supply air inlet 30 and the return air outlet 32, and a second set of screws spaced apart in a second front-to-back row located on a second side of the supply air inlet and the return air outlet. Preferably, the screw holes 34, when used to secure the cooling system module 12 to the cabinet module 11, are positioned so that (i) the cooling system is supported on top of the cabinet module, (ii) the cooling system is configured to supply air from the evaporator directly to the interior of the refrigerator through the supply air inlet 30, and (iii) the cooling system is configured to return air from the interior of the refrigerator directly through the return air outlet 32.

[0033] 5 and 6 , the illustrated cabinet module 11 includes airflow passages configured to direct and distribute cool air through the cabinet interior. In particular, the illustrated cabinet module 11 includes one or more supply air exhaust plenums 36 and one or more return air plenums 38. In the illustrated embodiment, the exhaust plenums 36 and return air plenums 38 for each cooling system module 12 are separate ducts (i.e., there is a separate exhaust and return plenum for each cooling system module 12), although it is envisioned that these ducts can be combined such that a common return air plenum and a common supply air plenum are used for two or more cooling system modules. In one or more embodiments, the supply air exhaust plenum 36 extends along the rear wall 16 from an open upper end to an enclosed lower end. Preferably, each supply air inlet opening 30 opens at the upper end of each supply air exhaust plenum 36. Each supply air exhaust plenum 36 includes a front plenum wall 40 defining a plurality of holes. The holes allow supply air to flow into the free refrigerated space within the cabinet module 11. In this case, each front plenum wall 40 defines the rear of the cabinet's free refrigerated space (see FIG. 12A), and the door glass defines the front of the cabinet's free refrigerated space. In the illustrated embodiment, each front plenum wall 40 includes outlet openings at multiple vertically spaced locations that are oriented to allow cool air to flow across the merchandise supported on each shelf 24.

[0034] In one or more embodiments, each return air plenum 38 extends from a front end to a rear end along the underside of the top wall 18. The front end of each return air plenum 38 defines one or more inlet openings or holes that form an entrance through which return air is directed into the return air plenum. The rear end of the return air plenum 38 forms an opening that opens toward the return air outlet 32. Each return air plenum 38 generally defines an upper end of the free refrigerated space within the cabinet module 11, and the bottom shelf 24, in the illustrated embodiment, defines an opposite lower end of the free refrigerated space.

[0035] As can be seen, the cabinet module's airflow passages are configured to direct chilled air from the supply air inlet 30 downward along the rear wall 18, before proceeding forward through the free refrigerated space within the cabinet. After absorbing heat and moisture from within the cabinet, the return air is generally drawn upward at the front of the cabinet and directed to flow rearward along the top wall 18 into the return air outlet 32. It will be appreciated that the specific arrangement of the airflow passages may differ from that shown without departing from the scope of this disclosure. For example, instead of directing air back-to-front through the free refrigerated space, the vending machine could be configured so that air flows front-to-back or side-to-side through the free refrigerated space. While the primary focus of this disclosure is the refrigerated cabinet, it is also contemplated that the temperature control module may be configured to heat or insulate the interior space.

[0036] As will be explained in more detail below, the illustrated refrigerated vending machine kit 10 is configured so that when the vending machine 10' is assembled, no part of the refrigeration system is located inside the cabinet, thereby enabling the cabinet module 11 to provide previously unattainable usable commercial space within a vending machine that can be accessed through a standard-height person's door.

[0037] In the illustrated embodiment, the cabinet module 11 has a free refrigerated space height FRSH (FIG. 12A) that extends from the bottom wall 20 to the return air plenum 38. For purposes of this disclosure, the "free refrigerated space height" is the continuous height along the cabinet module 11 that may be filled with merchandise and merchandise supports, such as shelves 24. Thus, the free refrigerated space height excludes any portion of the interior of the refrigerated cabinet occupied by refrigeration system components, condensate removal components, or functional components not related to supporting, displaying, or accessing refrigerated items. In one or more embodiments, the free refrigerated space height FRSH is at least 60 inches (e.g., at least about 61 inches, at least about 62 inches, at least about 63 inches, at least about 64 inches, at least about 65 inches, at least about 66 inches, about 68 inches ±0.5 inches). Larger free refrigerated space heights are possible within the scope of this disclosure. For example, in applications requiring more packing but still requiring the cabinet to fit through a person-height doorway, thinner foam panels and thinner ducting may be used.

[0038] The illustrated cabinet module 11 also includes a free refrigerated space depth FRSD ( FIG. 12 ), and in one or more embodiments, the free refrigerated space depth FRSD of the refrigerated vending machine is at least about 22 inches (e.g., at least about 23 inches, at least about 24 inches, at least about 25 inches, at least about 26 inches, at least about 27 inches, at least about 28 inches, at least about 29 inches, at least about 30 inches, at least about 31 inches, about 32 inches ±0.5 inches). As noted above, thinner foam panels and thinner ducting may be used in applications requiring more packing but where the cabinet will still fit through a human-height doorway. In the illustrated embodiment, the depth of the shelves 24 is slightly less than the free refrigerated space depth FRSD of the cabinet module 11 to allow airflow in front of the shelves.

[0039] As shown in FIG. 12A , the illustrated embodiment of cabinet module 11 includes a free refrigerated space cross-sectional area in a front-to-back plane perpendicular to the width of the cabinet module. In one or more embodiments, the free refrigerated space cross-sectional area is at least approximately the area defined by the product of the free refrigerated space height FRSH and the free refrigerated space depth FRSD, as described above. In one or more embodiments, the free refrigerated space cross-sectional area is greater than 1350 square inches (e.g., greater than 1500 square inches, greater than 1700 square inches, greater than 1900 square inches, greater than 2000 square inches, or greater than 2100 square inches). The volume of the free refrigerated space can be calculated by multiplying this free refrigerated space cross-sectional area by the refrigerated space width IW ( FIG. 4 ), which extends from the interior of one lateral sidewall 14 of cabinet module 11 to the interior of the other lateral sidewall.

[0040] As described above, the illustrated cabinet module 11 is configured to include a set of shelves 24 for holding items within a portion of its free refrigerated storage space. FIG. 12A shows a cross-section of the free refrigerated storage space FRS of the illustrated cabinet module 11, and for comparison, FIG. 12B shows a cross-section of shelf space SS, which can support items within the free refrigerated storage space. Here, shelf space defines the packing volume of the cabinet module 11. In other words, the packing volume of the illustrated cabinet is equal to the shelf space. However, it will be understood that other types of intra-cabinet storage may be used, and the packing volume need not necessarily be the same as the shelf space. In the illustrated embodiment, the shelves 24 include a bottom shelf on the bottom wall 20 of the cabinet 11 and a set of cantilevered shelves spaced above the bottom shelf. In one or more embodiments, the front-to-back depth CSD of the cantilevered shelf is at least about 20 inches (e.g., at least about 21 inches, at least about 22 inches, at least about 23 inches, at least about 24 inches, greater than 24 inches, or 25 inches ±0.5 inches). In certain embodiments, the depth BSD of the bottom shelf 24 is greater than the depth CSD of the cantilevered shelf 24. For example, in one or more embodiments, the depth of the bottom shelf is greater than 26 inches (e.g., at least about 27 inches, or at least about 28 inches).

[0041] In the illustrated embodiment, the rear end of the shelf space is bounded by a rear guard 42. The rear guard 42 includes an upright grill spaced from the front of the front wall 40 of the discharge plenum 36 that is used to ensure proper airflow by preventing items from being pushed rearward and contacting the discharge plenum. Above each shelf 24, the shelf space extends forward from the rear guard 42 to the front edge of the shelf and vertically from the plane of the shelf to the plane of the adjacent shelf above (or, in the case of the top cantilevered shelf, to the bottom wall of the return air plenum 38). As shown in FIGS. 12A and 12B , the shelf space SS is narrower than the free refrigeration space FRS because it does not include the space occupied by the item guard 42 and the space forward of the shelf 24 that allows airflow to the front entrance of the return air plenum 38. In one or more embodiments, the shelf space SS is 1550 in. in a front-to-back cross section perpendicular to the width of the cabinet module 11. 2 (For example, 1600 in 2 Over 1650in 2 Over 1700in 2 12) is greater than the maximum shelf space provided by a deep bottom shelf. Those skilled in the art will appreciate that this represents a significant increase in shelf space compared to conventional refrigerated vending machines that fit through a person-height doorway. However, because the refrigeration system module 12 occupies space at the bottom of the interior of the cabinet, only the increased shelf space provided by a deep bottom shelf is available.

[0042] The large depth reach-in cabinet 11 described above is suitable for access through a human-height double-door doorway. However, if only a human-height single door is available, it may be useful to create a cabinet with a shorter free refrigerated space depth and / or shelf depth. In any event, embodiments of the field-installable refrigerated vending machine kit 10 within the scope of this disclosure allow for effective use of the entire space occupied by the illustrated vending machine.

[0043] The space occupied by a unit can be considered in at least two ways. First, the space can be defined in terms of "unit dimensions," which are the exterior dimensions defined by the cabinet walls and doors independent of its environment. In this regard, with reference to FIG. 12, the unit height UH of the cabinet module 11 extends from the top of the top wall to the bottom, the unit depth UD extends from the rearmost component to the front face FP defined by the cabinet door 22 (excluding handle) or kick plate 21, and the unit width UW (FIG. 4) extends from the exterior surface of one side wall 14 to the exterior surface of the other side wall. Assuming the area is a simple rectangular cube, the unit volume can be calculated as unit height UH x unit depth UD x unit width UW. In one or more embodiments, the volume of the free refrigerated space is at least 60% of the unit volume. Similarly, the free refrigerated space cross-sectional area is at least 60% (eg, at least 63% or at least 65%) of the unit cross-sectional area measured as unit depth UD by unit height UH.

[0044] A second way to conceptualize how much space occupied by the cabinet module 11 is usable is to compare the dimensions of the free refrigerated space to the dimensions the cabinet module will occupy when installed in a building. For many prior art refrigerated vending machine kits, these "occupation dimensions" are substantially larger than the unit dimensions (e.g., greater than 3 inches in the front-to-back direction). This is because prior art cabinet modules must be mounted substantially offset from the support structure on which the cabinet is placed, such as a store wall or the back of an adjacent cabinet, due to conduit, wiring, tubing arrangements, and the area required to vent heat from the condensing unit. However, in one or more embodiments, the illustrated refrigerated vending machine 10 is configured to mount and operate with zero offset from the support structure. In certain embodiments, the cabinet module is configured to define an occupied volume. The occupied volume is defined by an occupied height extending from the floor to the top of the top wall, an occupied depth extending from the support structure on which the cabinet is placed to the front face FP, and an occupied width extending from the exterior surface of one side wall 14 to the exterior surface of the other side wall. When installed with zero offset, these occupancy dimensions of the illustrated cabinet module 11 are equal to unit dimensions UH, UD, and UW. In an exemplary embodiment, the occupancy depth of the cabinet 11 is less than 40 inches. The occupancy volume can be calculated as the occupancy height (e.g., UH) times the occupancy depth (e.g., UD) times the occupancy width (e.g., UW). In one or more embodiments, the volume of the free refrigeration space is at least 60% of the occupancy volume. Similarly, the free refrigeration space cross-sectional area is at least 60% (e.g., at least 63%, at least 65%) of the occupancy cross-sectional area measured as the occupancy depth times the occupancy height.

[0045] Another useful metric of how effectively the cabinet module 11 utilizes space is to compare the shelf space volume (e.g., the internal width IW of the cabinet module times the shelf space cross-sectional area SS shown in FIG. 12B) to the occupied footprint of the installed cabinet (e.g., occupied depth (e.g., UD) times occupied width (e.g., UW)). In the illustrated embodiment, the ratio of shelf space volume to occupied footprint is 3.25 ft 3 / ft 2 Larger than (e.g., 3.4 ft 3 / ft 2 Larger than 3.5ft 3 / ft 2 Greater than or equal to 3.6ft 3 / ft 2 (greater than 40 in.) A relevant metric for indicating how effectively a cabinet module 11 utilizes its occupied space is the ratio of the cross-sectional area of the shelf space to the occupied cabinet depth. In one exemplary embodiment, the ratio of the cross-sectional area of the shelf space to the occupied cabinet depth is greater than 40 in. 2 / in or more (41in 2 / in or more, or 42in 2 / in).

[0046] 7-9, in an exemplary embodiment, the cooling system module 12 comprises an off-the-shelf cooling system. Here, the term "off-the-shelf" means that the components included in the cooling system module 12 are assembled at a manufacturing facility remote from the final location where the cooling system module will be placed on the separate cabinet module 11. The term "cooling system" refers to a complete cooling circuit that includes all the components necessary to circulate a refrigerant between a heat absorption heat exchanger and a heat rejection heat exchanger.

[0047] In an exemplary embodiment, each prefabricated refrigeration system module 12 includes a single, sealed refrigeration circuit. Therefore, no on-site refrigeration connections need to be made. This substantially reduces the likelihood of refrigerant leaks during use of the refrigerated vending machine 10' compared to comparable field-installable vending machine systems that require on-site refrigeration connections. The inventors recognize that field installation of some remote condensing units utilizes vent, access, and charging ports that can result in refrigerant leaks, allowing non-condensable liquid to enter the refrigeration system and potentially degrade performance. To provide a fully sealed refrigeration module, the vending machine 10' does not include access or inspection ports. In an exemplary embodiment, instead of inspection ports, high-side and low-side pressure transducers, such as those described in U.S. Provisional Patent Application No. 63 / 152,363, filed February 23, 2021, and entitled "Ice Maker," are integrated into the refrigeration system to output pressure signals. The entire contents of which are incorporated herein by reference for all purposes. As described herein, a local or remote display can be used to display pressure data from the pressure transducer for diagnostic purposes, as needed. While U.S. Provisional Patent Application No. 63 / 152,363 specifically relates to the use of a pressure transducer integrated into the sealed refrigeration system of a dedicated ice maker, it will be apparent that the same general type of pressure transducer can be used in the same general manner in the sealed refrigeration system module 12 described herein. Furthermore, unlike remote refrigeration systems that require multiple containment devices to account for the large number of different positions, conduit sizes, piping, and wiring sets that arise when connecting cabinets to condensing units of various configurations, in the present disclosure, refrigeration module 12 does not use a containment device or vessel to store excess refrigerant.

[0048] In an exemplary embodiment, the refrigeration circuits include a natural refrigerant, such as R290. Those skilled in the art will appreciate that the use of such natural refrigerants may be subject to certain laws and regulations, particularly those governing maximum injection amounts. In one or more embodiments, the refrigeration system module 12 includes one or more sealed refrigeration circuits with an injection amount of R290 refrigerant of 150 grams or less. In other embodiments, the refrigeration system module may include one or more refrigeration circuits using other types of refrigerants and / or other injection amounts (e.g., injection amounts greater than 150 grams).

[0049] Each illustrated cooling system module 12 includes a complete compression-driven refrigeration circuit, including an evaporator assembly 50, a compressor 52, a condenser assembly 54, a dryer 56, an expansion valve 58, and interconnecting piping. It is contemplated that a prefabricated cooling system 12 may include two or more refrigeration circuits as part of the same module in certain embodiments. Those skilled in the art will be familiar with the basic components, function, and operation of these components in a compression-driven refrigeration circuit. It is contemplated within the scope of this disclosure that other temperature control modules may provide heat and / or a secondary refrigerant circuit may be used to maintain a desired temperature inside the cabinet. As described in more detail below, in the illustrated embodiment, each prefabricated cooling system module 12 (cooling system) includes an independent temperature controller 68 configured to drive the cooling system based on a detected temperature.

[0050] In an exemplary embodiment, each refrigeration system compressor 52 is a variable speed compressor. As will be explained in more detail below, the use of variable speed compressors enhances the ability to mount multiple refrigeration system modules 12 in the same cabinet module 11 to cool a common refrigerated space. It will be appreciated that constant speed compressors may also be used in certain embodiments.

[0051] In the illustrated embodiment, the condenser assembly 54 (broadly, a heat rejection heat exchanger) comprises an air-cooled condenser unit including a condenser fan 60 configured to draw ambient air from the room to the outside through a condenser coil 62. In certain embodiments, the condenser fan 60 may include a constant speed fan, a variable speed fan, or a combination thereof to suit the requirements of the application. It is also contemplated that in one or more embodiments, an off-the-shelf cooling system may include a water-cooled condenser unit.

[0052] The evaporator assembly 50 (broadly defined as a heat absorption heat exchanger) includes an evaporator coil 64 where liquid refrigerant absorbs heat and converts to vapor. Other heat exchangers, such as a heating element or a secondary refrigerant / glycol coil or loop, can also be used to modify the temperature inside the free refrigeration space. The evaporator assembly 50 further includes an evaporator fan 66 configured to draw return air from the cabinet module 11 through the evaporator coil 64 and cool the air before discharging it into the cabinet module through the supply air inlet 30. Like the condenser fan 60 described above, the evaporator fan 66 can be constant speed, variable speed, or a combination thereof to provide cooling output tailored to application requirements. These fans are used to transfer air volume from inside the conditioned space of the cabinet 11 to the cooling / heating module and to transfer air volume from around the cooling / heating module through the heat exchanger.

[0053] Various additional sensors and transducers may be used to monitor the operating characteristics of the cooling system, and in one or more embodiments, the temperature controller 68 is configured to receive input from these sensors and transducers.

[0054] In one or more embodiments, the temperature controller 68 is configured to control the compressor 52 to selectively maintain a refrigeration temperature in the range of -20°F to 75°F. The temperature controller 68 may also be configured to control the speed or power of the variable speed condenser fan 60 and / or the variable speed evaporator fan 66 based on algorithms that perform pulldown, recovery, energy conservation, or preventative maintenance operations (described below). In certain embodiments, the refrigeration system module further includes a wired transceiver (e.g., RS485) or a wireless transceiver (e.g., cellular modem, Bluetooth, Wi-Fi, and other radio frequency devices) configured to provide communication between the vending machine controller and a remote communication device. An exemplary method for utilizing such remote communication is described in U.S. Patent No. 9,863,694, the entire contents of which are incorporated herein by reference.

[0055] Generally, the off-the-shelf cooling system modules 12 and cabinet modules 11 include interconnecting hardware configured to removably and operably connect the off-the-shelf cooling system modules to the cabinet modules for cooling the interior of the cabinet modules and such that the off-the-shelf cooling system modules are entirely external to the cabinet modules. More specifically, the interconnecting hardware in the illustrated embodiment is configured to mount each cooling system 12 on the top wall 18 of the cabinet module 11, with each cooling system 12 being entirely mounted on the top wall of the cabinet module for cooling the interior of the cabinet module. Preferably, each cooling system module 12 is configured to removably and operably connect to the cabinet module 11 (e.g., top wall 18) such that, when connected, the cooling system module 12 can cool the interior of the cabinet. Preferably, the interconnecting hardware also allows the cooling system modules 12 to be disconnected from the cabinet module 11, allowing the modules to be moved separately, if necessary, through a standard-height door to another location.

[0056] 9-15, the illustrated cooling system module 12 includes a substrate 70 that supports the entire cooling circuit and control system described above. The substrate 70 also provides at least some facets for interconnect fittings that facilitate operative connection with the cabinet module 11. In the illustrated embodiment, the substrate 70 includes an evaporator section 72 and a condenser section 74. The cooling system is supported on the substrate such that the evaporator assembly 50 is located above the evaporator section 72, and the condenser assembly 54, compressor 52, and dryer 56 are located above the condenser section 74. In the illustrated embodiment, the condenser section 74 and the evaporator section 72 are formed from separate pieces of material that are assembled to form the substrate. For example, in one or more embodiments, the condenser section 74 and the evaporator section 72 are assembled by mechanical fasteners. In the illustrated embodiment, the evaporator section 72 forms the rear end of the substrate 70, and the condenser section 74 forms the front end. This configuration allows an evaporator section 72 to be installed above each supply air inlet 30 and each return air outlet 32 when using the cooling system module 12 .

[0057] The evaporator section 72 forms the bottom wall of an insulated evaporator enclosure 76. The evaporator enclosure 76 is broadly configured to enclose the evaporator assembly 50 and provide fluid communication between the supply air exhaust plenum 36 and the return air plenum 38 of the cabinet module 11. The evaporator enclosure 76 is generally configured to separate the evaporator assembly 50 from the condenser assembly 54. Thus, the illustrated evaporator enclosure 76 includes an insulating front wall between the condenser section 74 of the base plate and the evaporator section 72, which provides thermal isolation between the evaporator assembly 50 and the condenser assembly 54. The illustrated evaporator enclosure 76 further includes left and right side walls and a rear wall. These walls, together with the front wall, define a 360° insulated perimeter around the evaporator assembly 50. The evaporator enclosure 76 also includes a removable lid 78. The removable lid 78 can be removed as needed to access the evaporator assembly 50 for inspection and maintenance.

[0058] The evaporator section 72 of the base plate 70 defines a supply air outlet 80 and a return air inlet 82. In the illustrated embodiment, the supply air outlet 80 comprises an elongated slot extending widthwise of the base plate 70 and penetrating the thickness of the base plate adjacent the rear wall of the evaporator enclosure 76. The return air inlet 82 is similarly an elongated slot extending widthwise and spaced forward of the supply air outlet 80. In other words, in the illustrated embodiment, the return air inlet 82 and the supply air outlet 80 are spaced forward and backward from one another. The return air inlet 82 and the supply air outlet 80 are sized and positioned to fit the return air outlet 32 and the supply air inlet 30, respectively. Thus, when the cooling system module 12 is operably connected to the cabinet module 11, the supply air outlet 80 provides fluid communication between the interior of the evaporator enclosure 76 and the supply air inlet 30, and the return air inlet 82 provides fluid communication between the interior of the evaporator enclosure and the return air outlet 32.

[0059] Preferably, the kit 10 includes seals for sealing the interface between the top wall 18 of the cabinet module 12 and the base plate 70 of the cooling system module 12 around the supply air openings 30, 80 and the return air openings 32, 82. For example, one of the pre-fabricated cooling system module 12 and the cabinet module 11 preferably includes a supply air gasket 84 configured to extend 360° around the supply air openings 30, 80 and another return air gasket 86 configured to extend 360° around the second return air openings 32, 82. In the illustrated embodiment, the pre-fabricated cooling system module 12 includes a supply air gasket 84 on the underside of the base plate 70 that extends 360° around the supply air outlet. The pre-fabricated cooling system module 12 further includes a return air gasket 86 on the underside of the base plate 70 that extends 360° around the return air inlet 82. These seals could alternatively be attached to the top surfaces of the cabinet modules. In the illustrated embodiment, gaskets 84, 86 comprise two separate compressible closed-cell foams. However, a single compressible material and compressible materials other than closed-cell foams may be used without departing from the scope of this disclosure. Alternatively, interlocking plastic shapes could be used to form the seal between the refrigeration module and the cabinet module.

[0060] 12 and 13 , the substrate 70 is configured to couple to the top wall 18 of the cabinet module 11 such that the supply air gasket 84 is compressed between the substrate and the top wall to form a liquid seal that extends 360° around the supply air outlets 82 and the supply air inlets 32. This allows the evaporator fan 66 to blow air through the evaporator coil 64, cooling the air, and then supply air directly into the cabinet 11 through the supply air outlets 80 and the supply air inlets 30. Similarly, the substrate 70 is configured to couple to the top wall 18 of the cabinet module 11 such that the return air gasket 86 is compressed between the substrate and the top wall to form a liquid seal that extends 360° around the return air outlets 32 and the return air inlets 82. To this end, the evaporator fan 66 is configured to draw return air from the free refrigeration space of the cabinet 11 into the front end of the return air plenum 38, then rearward along the return air plenum, through the return air outlet 32 of the cabinet module 11, and then further upward through the return air inlet 82 of the cooling system module 12 and into the evaporator enclosure 76. After directing the air to flow through the evaporator coil 64 and into the evaporator enclosure 76, the fan forces the supply air through the supply air outlet 80 of the cooling system module 12 and the supply air inlet 30 of the cabinet module 11, and along the supply air discharge plenum 36 to the free refrigeration space of the cabinet.

[0061] 11 and 14-18, the cooling system module 12 further includes at least one mounting rail 90. The at least one mounting rail 90 is configured to facilitate lifting the cooling system module 12 as a unit from a lower support surface, such as the ground, up to the top wall 18 of the cabinet module 11. Further, each rail 90 is configured to be removably secured to the top wall 18 of the cabinet module 11 to operably connect the cooling system module 12 to the cabinet module. In the illustrated embodiment, the cooling system module 12 includes first and second rails 90. When the prefabricated cooling system module 12 is operably connected to the top wall 18 of the cabinet module 11, the first and second rails 90 are connected to opposite lateral edges of the base plate 70 and extend generally in the front-to-rear direction. Each rail 90 acts as a support beam, providing bending strength to the base plate 70 and preventing it from bending or breaking under the weight of the cooling circuit when being lifted.

[0062] Each rail 90 is formed from a generally U- or J-shaped metal channel. As shown in FIG. 18 , each rail 90 includes an inboard adjustment flange 92 for adjustably mounting the rail to the base plate 70, a bottom web 94 extending laterally outward from the adjustment flange, and an upwardly facing lip 96 defining the lateral outer side of the rail. Thus, the illustrated rail 90 can be seen to include a lower portion having a generally U-shaped profile (also known as a double-return profile). The U-shaped profile provides a non-puncturing gripping surface for a technician's hand when gripping the rail 90 while lifting the cooling system module 12 over the cabinet module 11. Additionally, the U-shaped profile of the lower portion of the rail 90 allows the cooling system module 12 to slide along the top wall of the cabinet module 11 while supported on the rail without substantially scratching or gouging the cabinet module. Thus, the illustrated rail 90 includes a smooth bottom surface.

[0063] The adjustment flange 92 is configured to facilitate adjustment of the rail between a lowered position ( FIG. 16 ) and a raised position ( FIG. 17 ). In the illustrated embodiment, the adjustment flange 92 includes a pair of vertically elongated mounting slots 98 for mounting the rail to the base plate 70. Each mounting slot 98 is configured to receive a removable fastener therethrough. Each mounting slot 98 is configured to accommodate a corresponding pair of mounting points 100 ( FIG. 15 ) on the lateral edges of the base plate 70. In the illustrated embodiment, the base plate mounting points 100 also include holes for receiving removable fasteners 101, such as screws. In the lowered position, each rail 90 can be secured to the base plate 70 by threadably advancing screws 101 through the upper ends of the mounting slots 98 and into mounting holes 100 formed on each side of the base plate 70. Additionally, in the raised position, each rail 90 can be secured to the base 70 by threadably advancing a screw 101 through the lower end of the mounting slot 98 and into a mounting hole 100 formed on each side of the base 70.

[0064] As shown in FIGS. 16 and 17 , the bottom portion of each rail 90 protrudes below the bottom surface of the base plate 70 and gaskets 84, 86 in the lowered position, but is either (i) flush with the bottom surface of the base plate or (ii) spaced above the bottom surface of the base plate when the rail is in the raised position. This allows the cooling system module 12 to be first placed on the top wall 18 of the cabinet module 11 with the rails 90 in the lowered position, with the weight of the cooling system module supported on the rails. This prevents the gaskets 84, 86 from being compressed before the cooling system module 12 is properly positioned along the top wall 18, allowing the cooling system module to easily slide along the top wall. After being initially placed on the top wall 18 of the cabinet module 11, the cooling system module 12 can slide along the top wall to a position where the cooling system module is operatively aligned with the cabinet module, with the rails 90 acting as a sliding contact.

[0065] The bottom web 94 of each rail 90 defines a set of integrated mounting points 102 used to secure the cooling system module 12 to the cabinet module 11 in an operational position. In particular, the bottom web 94 defines a plurality of screw holes 102 arranged to match the integrated screw holes 34 in the top wall 18 of the cabinet module 11. The rearward ones of the screw holes 102 are aligned with mounting brackets 103 connected to the side of the base plate 70 (e.g., screwed to the side wall of the evaporator enclosure 76). Each cooling system module 12 is configured to be operably connected to the cabinet module 11 by threadably advancing a screw 105 installed in each screw hole 102 formed in the bottom web of each rail 90 into a corresponding screw hole 34 in the top wall 18 of the cabinet module 11. The rearward screws 105 are secured to the top wall of the cabinet 11 via the mounting brackets 103.

[0066] In summary, the refrigerated vending machine kit 10 includes separate cabinet and refrigeration system modules 11, 12, which are removably and operably coupled and integrated into a module using interconnecting elements or fittings. In the illustrated embodiment, the interconnecting fittings include supply air inlet and outlet openings 30, 80 and an supply air gasket 84, which align to provide a substantially sealed fluid path from downstream of the evaporator assembly 50 to the supply air exhaust plenum 36 of the cabinet 11. Similarly, the interconnecting fittings of the illustrated kit 10 include return air inlet and outlet openings 32, 82 and a return air gasket 86, which align to provide a substantially sealed fluid path from the cabinet's refrigerator interior to the upstream side of the evaporator assembly 50. Furthermore, the interconnecting fittings of the illustrated kit 10 include a set of mechanical attachment points 34, 102, whereby the refrigeration system module 12 is configured to be removably secured to the top wall 18 of the cabinet module 11 in an operational position. This is done, for example, by threadably advancing a screw 105 through a threaded hole 102 in the cooling system module 12 and into a threaded hole 104 formed in the top wall 18 of the cabinet module 11 .

[0067] A method for mounting one or more cooling system modules 12 to a cabinet module 11 will now be briefly described. In an exemplary embodiment, the kit 10 includes instructions for carrying out this method. First, the prefabricated cabinet module 11 and cooling system module 12 are separately moved through a doorway to the desired location within the building. After removing the packaging, a technician can begin the process of placing the cooling system module 12 on the cabinet module 11. The rails 90 of the prefabricated cooling system module 12 are initially in the lowered position ( FIG. 16 ). The installer can lift the cooling system module 12 onto the top wall 18 while grasping the module by the rails 90. After placing the cooling system module 12 on the top wall 18, the installer can slide the cooling system module back and forth and sideways along the top wall, as needed, until the screw holes 102 in the bottom webs of the rails align with the screw holes 34 in the top wall. When the screw holes 102 are aligned with the screw holes 34 in the top wall, the supply air outlet 80 and the supply air inlet 30 are substantially aligned, and the return air inlet 82 and the return air outlet 32 are substantially aligned (in certain embodiments, the modules may include snap-in elements (not shown) that engage when the cabinet module is in the correct position).

[0068] In this position, as shown in FIGS. 16A-16B, screws 105 can be threadably advanced through the forward-most bottom screw holes 102 of the rails 90 and into the forward-most screw holes 34 in the top wall 18 of the cabinet module 11 to temporarily hold the cooling system module 12 in the aligned position. Next, as shown in FIG. 17A, the installer can loosen screws 101 from the mounting slots 98 in the adjustment flange 92. This causes the base plate 70 to drop between the rails 90, compressing the gaskets 84, 86. This creates a fluid seal around the supply air openings 30, 80 and the return air openings 32, 82 at the interface between the cabinet module 11 and the cooling system module 12. Finally, as shown in FIG. 17B, the installer can advance screws 105 through the mounting bracket 103, the rear rail screw holes 102, and the rear cabinet screw holes 34 to secure the cooling system module 12 to the cabinet. Finally, screws are tightened within the mounting slots 98 to secure the rails 90 in the raised position, thereby operably connecting the cooling system module 12 to the cabinet module 11 .

[0069] 9 and 19 , in the illustrated embodiment, the cooling system module 12 includes an integrated condensate removal system 104 for removing condensation by-products of refrigeration that form on the evaporator coil 64 during use. The condensate removal system 104 is an off-the-shelf component of the cooling system module 12 that does not require field assembly for operation. The condensate removal system 104 includes an evaporator drain pan 106 located below the evaporator coil 64 and above the evaporator section 72 of the substrate 70 (inside the evaporator housing), a condensate drain pan 108 located above the condenser section 74 of the substrate (outside the evaporator housing), a drain tube 110 through which condensate in the evaporator drain pan flows into the condensate drain pan, and a heating element 112 in thermal communication with the condensate drain pan for heating and evaporating the contained condensate. In applications where condensate may freeze in the drain line, a drain tube heater or conductive material to burn heat from the defrost heater is also required. These heating elements ensure that condensate flows between the two drain pans 106, 108. Preferably, the condensate removal system 104 does not require a groove pump to operate. Instead, water can flow by gravity from the evaporator drain pan 106 to the condensate drain pan 108. For example, the drain conduit 110 includes an inlet fluidly connected to the bottom of the evaporator drain pan 106 and an outlet fluidly connected to the condensate drain pan 108 at a lower position than the inlet. In the illustrated embodiment, the heating element 112 includes a hot gas pipe of the cooling circuit. Additionally, the condenser fan 60 is oriented so that warm air from the condenser coil 62 flows across the top of the condensate drain pan 108, further heating the tray. Other heating elements may be used alone or in combination. Other examples of heating elements include electric condensate heaters, optionally with float switches or capacitive or electrical meters, which can be used to drive an electric circuit to provide electric heat generating surface area and / or a set of burning appliance wicks or pads. Additional controls may be provided to drive and control this electric heater circuit to provide additional heat to the condensate drain pan.

[0070] Referring to FIG. 20 , the integration of the condensate removal system 104 into the prefabricated refrigeration system module 12 may enable the refrigerated vending machine 10′ to have a larger packing volume within a given footprint of a retailer's premises, particularly compared to other field-installable refrigerated vending machine kits known to those skilled in the art. As shown in FIG. 20 , the field-installable refrigerated vending machine kit 10 is configured to be deployed as a refrigerated vending machine 10′ by removably and operably connecting the prefabricated refrigeration system module 12 to the top wall 18 of the cabinet module 11 and positioning the rear wall 16 of the cabinet module against a store wall RW (broadly, a support structure). As shown, the rear wall 16 of the cabinet module 11 is spaced from the store wall RW by a separation distance SD. The separation distance SD may be less than 3 inches (e.g., less than 2 inches, less than 1 inch, or zero offset) in one or more embodiments. This is possible, inter alia, because the retail dispenser 10' formed by the kit 10 does not require any vertical condensate lines, pipes, wiring trenches, or mechanical insulation along the back of the cabinet 11.

[0071] As can be appreciated in light of the above, in one aspect, the present disclosure provides a high-capacity vending machine 10' configured to be cooled entirely to refrigerator and freezer temperatures by a pre-fabricated refrigeration system 12. More particularly, the present disclosure provides a 10,000 in refrigerator / freezer temperature-cooled vending machine configured to be cooled entirely to refrigerator and freezer temperatures by a sealed refrigeration system injected with natural refrigerants at injection levels compliant with major global regulatory standards. 3 greater than (e.g., 12,500 in 3 Larger than 15,000 in 3 Greater than 20,000 in 3 Greater than 25,000 in 3For example, in one or more embodiments, the present disclosure provides a high-capacity vending machine 10' having a shelf space capacity of 150 g or more. For example, in one or more embodiments, the present disclosure provides a high-capacity vending machine 10' entirely cooled by multiple refrigeration systems 12 operating with a 150 g or less charge of R290 refrigerant. To achieve such high capacity using only off-the-shelf natural refrigerant refrigeration, the inventors have developed a novel system in which multiple refrigeration systems 12 are arranged to cool the same common refrigerated space.

[0072] In the illustrated cabinet 11, the free refrigerated space is one continuous refrigerated space. Throughout this disclosure, the term "common refrigerated space" is used to describe such one continuous refrigerated space in a vending machine 10' that includes multiple refrigeration systems for cooling the same undivided (i.e., common) refrigerated space.

[0073] Generally, a refrigerated vending machine 10′ according to the present disclosure can include multiple separate refrigeration systems 12 for cooling a common refrigerated space, with each refrigeration system including an independent temperature controller 68 configured to control that refrigeration system independently of the other refrigeration systems. As described above, each refrigeration system 12 includes a separate refrigeration circuit with at least one evaporator assembly 50, compressor 52, condenser assembly 54, expansion valve 58, and interconnecting piping. While an exemplary embodiment of a refrigerated vending machine 10′ uses field-installable refrigeration system modules 12, it is also contemplated that aspects of the present disclosure relating to the integration of multiple independent temperature control devices with multiple refrigeration systems can be used in fully self-contained refrigerated cabinets that use multiple refrigeration systems. In an exemplary embodiment, each independent temperature controller 68 is a digital temperature controller (e.g., a Dixell XR70CH temperature controller is one of many suitable temperature controllers). However, in one or more embodiments, other types of temperature controllers (e.g., pressure controllers, analog thermostats) may be used.

[0074] As described above, the illustrated cabinet 11 has a width UW, and separate cooling systems 12 are configured to be operably connected to the cabinet at multiple locations spaced apart along the width of the cabinet. Each cooling system module 12 includes a unique air temperature sensor 69 (schematically illustrated in FIG. 24 , e.g., a thermistor or RTD) configured to detect the air temperature of the common refrigerated space at each location on the cabinet 11 corresponding to the location of the cooling system 12. Thus, the illustrated vending machine 10′ provides individual temperature sensors 69 for independent temperature controllers 68 at locations spaced apart along the width of the cabinet 11. In an exemplary embodiment, each temperature sensor 69 is located in a return air aisle, e.g., the return air plenum 38 or return air ports 32, 82. Each temperature sensor 69 is operably connected to a temperature controller 68 and outputs a signal indicative of the temperature detected at each location. Each independent temperature controller 68 is configured to individually control each cooling system 12 based on the air temperature detected at each location. As will be explained in more detail below, the inventors believe that cooling a common refrigerated space within cabinet 11 by independently controlling multiple individual refrigeration systems 12 substantially enhances the robustness of the vending machine refrigeration system and protects temperature-sensitive goods better than is currently possible with conventional refrigeration solutions.

[0075] Referring to FIG. 2 , each of the multiple cooling systems 12 is contained within a common air space defined by the enclosure 26. Furthermore, at least one cooling system 12 is positioned such that the condenser fan 60 blows warm air in a direction generally toward the adjacent cooling system. The inventors recognized that this warm air can reduce the cooling capacity of the adjacent (downstream) cooling system 12. To mitigate the adverse effects of this warm air flow, as shown in FIG. 2 (also see FIG. 2B ), the illustrated vending machine 10′ includes one or more isolation devices 118 that provide thermal and fluid separation of adjacent condenser assemblies 54. In the illustrated embodiment, the isolation devices 118 include a partition wall between the condenser fans 60 of two adjacent cooling systems 12. The partition wall 118 is screw-mounted to the top wall 18 of the cabinet 11 and is upright, forming a divider between the adjacent cooling systems 12. The partition wall diverts airflow from the upstream condenser fan 60 away from the downstream cooling system 12. It is contemplated that other types of thermal isolation devices may be used to redirect air by the condenser fans away from adjacent heat exchangers. For example, in certain embodiments, the isolation devices include ducts for each condenser fan 60 that are configured to channel air displaced by each condenser fan away from the adjacent condenser.

[0076] As described above, each refrigeration system 12 includes a variable speed compressor 52. Each refrigeration system 12 further includes an inverter 120 connecting a temperature controller 68 to each compressor 52 to control the compressor speed. In other words, each refrigeration system 12 includes an inverter compressor. Each inverter 120 is operatively connected to a respective temperature controller 68, allowing the temperature controller 68 to output a control signal to the inverter 120. The inverter 120 is configured to change the frequency of the AC current output to the compressor 52, thereby driving the compressor at a speed proportional to the frequency of the AC current. This eliminates stop-start cycles and essentially reduces current inrush to the compressor 52 during startup. As described in more detail below, the illustrated vending machine 10' is configured to operate all refrigeration systems 12 from a single power input 122. Reducing current inrush during startup is essential to prevent the refrigerated vending machine from tripping a store circuit breaker or other current limiter.

[0077] Each independent temperature controller 68 is configured to adjust the speed of variable speed compressor 52 based on the air temperature detected at each location. In one or more embodiments, a user can use a user interface connected to temperature controller 68 to adjust the setpoint temperature for cooling system 12. In the illustrated embodiment, the setpoint temperature for each cooling system 12 is independently settable through each user interface, although it is contemplated that other embodiments can use a common interface for all independent temperature controllers 68 to ensure each independent temperature controller has the same setpoint.

[0078] The temperature controller 68 may use various methods to independently control the speed of each variable speed compressor 52. In one example, for each individual refrigeration system 12, if the sensed air temperature at each location is higher than the desired temperature, the independent temperature controller 68 is configured to also send a signal to the variable speed compressor inverter 120, as in the single-speed compressor case, and the inverter uses internal circuitry to set the compressor 52 speed. This method is referred to as a "drop-in" method. In the "drop-in" method, the inverter 120 uses internal parameters, timers, and circuitry to determine the speed at which the variable speed compressor 52 operates. For example, at a basic level, the temperature controller 68 may continuously signal the inverter to provide cooling, and the inverter 120 may be configured to gradually increase the speed of the compressor 52. The independent temperature controller 68 may also send a defrost signal to the inverter 120. The timers, parameters, and response times for each variable speed compressor 120 and inverter 52 are configured to allow multiple cooling systems 12 to operate in unison to uniformly cool the cabinet 11 and to compensate for lost cooling capacity if one of the cooling systems goes offline.

[0079] In another example, which may be referred to as a "proportional" control mode, each independent temperature controller 68 has a defined "proportional control band," e.g., a temperature range centered around a user-defined desired temperature setting. If the sensed air temperature at each location is greater than the desired temperature setting plus the proportional band, the temperature controller 68 communicates with the compressor 52 to provide a frequency output to the variable speed compressor inverter 120 operating at its fastest speed. If the sensed temperature falls within the proportional control band, the temperature controller 68 proportionally reduces the frequency output. In response, the inverter 120 reduces the speed of the variable speed compressor 52. Additionally, during defrost, cycle start, and cycle stop, the temperature controller 68 can output a unique frequency to the variable speed compressor inverter 120 to account for these transient conditions. Of course, it will be appreciated that, as an alternative to a frequency output, the temperature controller 68 can provide a serial output to the variable speed compressor inverter 120 for even more precise control and feedback. Serial control allows for the collection of information regarding the status of the variable speed compressor 52 and the inverter 120. Based on the mechanical system's ability to reach and maintain the desired temperature setting, integral and derivative signals are provided from the temperature controller 68 to the variable speed compressor inverter 120 to achieve the user-defined temperature setting. It will be further understood that more complex algorithms, such as a hybrid of the "drop-in" and "proportional" algorithms described above, can be used by each independent temperature controller 68 to set the compressor speed.

[0080] By equipping each refrigeration system 12 with a variable speed compressor 52 independently controlled by its own independent temperature controller 68, the illustrated refrigerated vending machine 10' is made substantially redundant, improving vending reliability in the event of an abnormality, particularly in the illustrated embodiment in which each refrigeration system 12 is entirely mounted on the top wall 18 of the cabinet 11 outside the refrigerated space. In conventional refrigerated vending machines, such as hybrid refrigerated vending machines, refrigeration repair often requires removing merchandise from the cabinet 11 to access the refrigeration system. Furthermore, a malfunction impairs the entire cooling capacity of the vending machine, preventing it from maintaining low temperatures during repairs. Conversely, if one of the refrigeration systems 12 of the vending machine 10' malfunctions, the malfunctioning unit can be repaired or replaced while the other refrigeration systems continue to provide cold air to the common refrigerated space. Furthermore, the variable speed control algorithms implemented by the independent temperature controllers 68 in the remaining refrigeration systems automatically compensate for a significant portion of the lost cold by increasing the compressor speed. Additionally, the field-installable kit feature of the illustrated cooling system module 12 allows for rapid replacement of a failed cooling system module with a new or repaired cooling system module without the need for a skilled technician and without entering a cold space.

[0081] 21-23, the illustrated refrigerated vending machine 10' with multiple refrigeration systems 12 utilizes only a single power input 122 and is configured to distribute power from the single power input to each of the multiple refrigeration systems 12 for cooling a common refrigerated space. The refrigerated vending machine 10' includes a main electrical box 124 (see also FIGS. 1 and 3), with the power input 122 comprising a power cord extending from the main electrical box. Typically, the power cord 122 terminates in a standard electrical plug-in connector appropriate for the application. In a typical embodiment, the power input 122 may comprise a grounded NEMA 6-30P power cable, although it will be appreciated that different amperage and conductor combinations, such as NEMA 14-30P, may be used depending on the amperage requirements and wiring method of a given application. Furthermore, in certain embodiments, the single power input 122 may be connected on-site by an electrician. Throughout this disclosure, the term "plug-in connector" refers to any type of male, female, or hermaphroditic electrical connector that allows for the formation of an electrical connection, accomplished without the need for a skilled electrician, by plugging two such connectors together and actuating an optional fastening mechanism (e.g., a latch, a threaded coupling nut, a bayonet lock, etc.) that may be part of the plug-in connector.

[0082] The main electrical box 124 is configured to distribute power and signals to the various systems of the vending machine 10'. The main electrical box 124 includes one or more electrical panels 126, 128 configured to facilitate plug-in connections from the individual cooling units 12 and cabinets 11.

[0083] Referring to FIG. 22 , the main electrical box includes a first electrical panel 126 from which the power input 122 extends. The first electrical panel 126 includes a plurality of signal and load plug-in connectors 130, 132, and 133. The signal and load plug-in connectors 130, 132, and 133 may include any suitable panel-mounted electrical connectors configured to mate (and optionally latch) with corresponding cable connectors. Such connectors are known to those skilled in the art and are sold by Amp, Inc. and Molex, among others. Each signal and load plug-in connector 130, 132, and 133 is configured to operably connect to a mating connector (e.g., a latching plug, not shown). The mating connectors terminate cables connected to cabinet systems (see FIG. 24 ), such as a door sensor circuit 140, a cabinet lighting system 142, a cabinet heating system 144, and / or a heating pressure relief valve 145. In the illustrated embodiment, plug-in connector 130 is configured to connect to door sensor circuit 140 (described in more detail below), plug-in connector 132 is configured to connect to lighting system 142 and heating system 144, and plug-in connector 133 is configured to connect to heating pressure relief valve 145. In the illustrated embodiment, first electrical panel 126 further includes a mode switch 146 configured to simultaneously switch each cooling unit between multiple switchable operating modes, such as between freezer mode and refrigerator mode. Activating mode switch 146 sends a signal to each independent temperature controller 68 to change its control algorithm from that for the freezer mode of operation to that for the refrigerator mode of operation, or vice versa.

[0084] 21 , the main electrical box 124 of the illustrated embodiment includes a set of plug-in connectors 134, 136 configured for connection to individual cooling systems 12. In the illustrated embodiment, the panel 128 includes three sets of connectors 134, 136, allowing the main electrical box to be operably connected to up to three independent cooling systems 12. The electrical panel 128 includes three high-voltage plug-in connectors 134 (or, broadly, multiple high-voltage plug-in connectors) operably connected to a single power input 122, allowing each cooling system 12 to draw power from the single power input through each of the high-voltage plug-in connectors 134. In an exemplary embodiment, each high-voltage plug-in connector 134 may include a 6-15R receptacle configured to mate with a 6-15P plug (not shown). The illustrated electrical panel 128 further includes three signal and load plug-in connectors 136 configured to facilitate electrical communication between the cooling systems 12 and the cabinet system. The signal and load plug-in connectors 136 are described in further detail below.

[0085] Referring to FIG. 23 , each cooling system 12 includes a dedicated electrical box 150 with a system-specific electrical panel 152. A system power cable 154 extends from the electrical box 150 and terminates in a plug-in connector (e.g., a 6-15P plug, not shown) configured to plug into one of the high-voltage plug-in connectors 134. The cable thereby operably connects the cooling system 12 to one of the power inputs 122 and draws power from the one power input for cooling a common refrigerated space. The illustrated system-specific electrical panel 152 also includes signal and load connectors 156. Another cable, not shown, configured to connect the cooling system 112 to the main electrical box 124. More specifically, such cable includes a first end terminated by a first plug-in connector configured to plug into one of the connectors 136 of the main electrical box 124 and a second end terminated by a second plug-in connector configured to plug into the plug-in connector 156 of the system-specific electrical box 150. In the illustrated embodiment, the system-specific electrical panel 152 further includes plug-in power connectors 158. The plug-in power connectors 158 may be used to provide power (via plug-in connections) to certain auxiliary systems (e.g., electric condensate heaters, connectivity gateways, top-mounted lighting and displays, etc.) that may be used in conjunction with the cooling system 12. In the illustrated embodiment, cables 160, 162 extend from each system-specific electrical box to carry power and control signals to and from the cooling system 12.

[0086] 21-23 , a brief description will be given of how the cooling systems 12 and the cabinet 11 are connected using the electrical boxes 124, 150. In the illustrated embodiment, after the cooling systems 12 are physically mounted on the cabinet, they can be electrically connected using only plug-in connectors, eliminating the need for a skilled electrician. In some embodiments, an installer physically attaches the main electrical box 124 to the cabinet module 11 during the field installation process. For example, the installer places the main electrical box in position on top of the cabinet 11 and secures the main electrical box 124 in place by driving screws into pre-drilled screw holes in the top of the cabinet 11. A power cable 154 from each cooling system 12 is plugged into one of the high-voltage connectors 134 on the main electrical box 124, and a separate cable is used to connect the signal and load connector 156 of each cooling system 12 to one of the signal and load connectors 136 on the main electrical box. To connect the door sensor circuit 140 of the cabinet 11 to the main electrical box 124, a cable associated with the door sensor (not shown) plugs into connector 130 on the main electrical box. To connect the cabinet heater 144 and cabinet lighting 142 to the main electrical box 124, cables (not shown) associated with these cabinet components plug into connector 132. Similarly, to connect the heating pressure relief valve 145 to the main electrical box 124, a cable (not shown) associated with this relief valve plugs into connector 133. Finally, the single power input 122 plugs into a building power outlet, providing power to all components of the vending machine 10' from a single power source.

[0087] FIG. 24 provides a schematic diagram showing how all components of the vending machine 10′ are wired together after connecting and powering the refrigeration systems 12 and cabinet systems 140, 142, 144, and 145 using the main electrical box 124 and the system-specific electrical box 150, as described above. In the illustrated example, two refrigeration systems 12 are shown in solid lines, representing two representative refrigeration systems 12 of the vending machine 10′. Dashed lines indicate how a third refrigeration system 12 could be connected to the main electrical box 124 via a plug-in connection without further modification to the system. While the illustrated electrical system is configured to accommodate up to three refrigeration systems 12, it is contemplated that in one or more embodiments, the main electrical box could be expanded to connect to four or more refrigeration systems. As shown, each refrigeration system 12 draws power from one power input 122 via a respective high-voltage connector 134. Each temperature controller 68 includes inputs for receiving signals from the door sensor circuit 140, the air temperature sensor 69, and the evaporator temperature sensor 170. Based on the temperature detected by the air temperature sensor 69, each temperature controller 68 is configured to activate a set of relays 164 that control the output to the compressor inverter 20, the evaporator fan 66, and the condenser fan 60. Thus, each temperature controller 68 is configured to independently control each cooling system 12 based on the temperature signals output from the temperature sensors 69.

[0088] Preferably, each temperature controller 68 is configured to output a cabinet control signal to one or more cabinet systems, such as cabinet lighting 142 and / or cabinet heater 144. Each of the illustrated temperature controllers 68 controls a relay 166, which provides the cabinet control signal to the cabinet heater 144. As illustrated, multiple temperature controllers 68 are connected in parallel to the cabinet heaters 144. Whenever any one of the temperature controllers 68 outputs a cabinet control signal to the cabinet heater 144, the cabinet heater is active. Various methods and algorithms for controlling the cabinet heaters of the refrigerated vending machine 10′ are known and may be used without departing from the scope of the present disclosure. In one embodiment, each temperature controller defines a duty cycle for the cabinet heater and outputs a control signal to independently control the cabinet heater according to the defined duty cycle. In the illustrated embodiment, a separate manual switch 168 controls the cabinet lighting 142. However, it is contemplated that in one or more embodiments, the cabinet lighting 142 may be controlled by the temperature controller 68. For example, multiple temperature controllers 68 are coupled in parallel to cabinet lighting 142, and when one of the temperature controllers outputs a cabinet control signal to cabinet lighting 142 at a given time, the cabinet lighting is activated. In the illustrated embodiment, main electrical box 124 hardwires heated pressure relief valve 145 to power source 122, causing the heater on the relief valve to run at 100% duty cycle. It will be understood that the heated pressure relief valve may draw power in other ways without departing from the scope of this disclosure.

[0089] In a typical embodiment, the door sensor circuit 140 includes multiple door sensors (e.g., one for each door 22) connected in series, and the door sensor circuits are configured to communicate in parallel with the temperature controllers 68. Thus, if any of the door sensors outputs a signal indicating that the respective door 22 is open, the door sensor circuit 140 sends a signal to all of the temperature controllers 68. The temperature controllers 68 are preferably configured to control the cooling system based on the signal from the door sensor circuit 140. In one embodiment, each temperature controller 68 is configured to turn off its respective evaporator fan 66 upon receiving a signal from the door sensor circuit 140 indicating that the door 22 is open. In a particular embodiment, the temperature controller 68 is configured to monitor the time that the door sensor circuit 140 continuously outputs a signal indicating that the door is open. Each temperature controller 68 is configured to (i) turn off the evaporator fan 66 for an initial time period, and (ii) turn the evaporator fan back on after the initial time period. This ensures that cooling is provided in the event of a door sensor failure or one of the doors 22 being stuck open.

[0090] In the illustrated embodiment, each cooling system 12 includes a defrost heater 172. The refrigerated vending machine 10' is configured such that, in each cooling system 12, each temperature controller 68 periodically executes a defrost cycle, turning on the defrost heater 172 and turning off the evaporator fan 66 for a set period of time. Generally, the refrigerated vending machine 10' is configured to execute a defrost cycle for each cooling system at a different time. More specifically, each independent temperature controller 68 independently executes a defrost cycle depending on the run time (e.g., compressor run time) of each system. The run time of each cooling system 12 is inherently different because each system operates with independent temperature control based on temperatures detected at unique locations. Each temperature controller 68 is configured such that the temperature controller periodically executes a defrost cycle, turning on the defrost heater 172 and turning off the evaporator fan 66 for a set period of time. Each independent temperature controller 68 is configured to monitor the elapsed running time since the last defrost for each cooling system 12 and to initiate the next defrost cycle when the elapsed running time exceeds a specified defrost interval.

[0091] A typical method for repairing a refrigerated vending machine 10' involves first removing a failed one of the refrigeration system modules 12 from the cabinet 11. Removal of the failed refrigeration system module 12 does not require the use of a specialized contractor. Rather, a technician can simply unscrew the rails 90 from the top wall 18 of the cabinet 11, disconnect the power cord 154 from the high-voltage receptacle 136, disconnect the cable from the plug-in connector 152, and then lift the failed refrigeration system 11 out of the cabinet's top wall 18. While the failed refrigeration system module 12 is being removed, the common refrigerated space of the cabinet 11 continues to be cooled by the remaining (operational) refrigeration system module or modules 12.

[0092] Removing the failed cooling system module 12 exposes one or more holes in the cabinet 11 (e.g., the cold air inlet 30 and the return air outlet 32). In an exemplary embodiment, after removing the failed cooling system module 12, the holes 30, 32 are plugged to minimize the loss of cold air through these holes. For example, in an exemplary embodiment, a technician plugs the holes 30, 32 with one or more pre-fabricated plug seals (not shown) made of a resiliently compressible sealing material, such as closed-cell foam. The plug seals are sized to sealingly receive within one or both of the holes 30, 32.

[0093] While the failed refrigeration system 12 is removed, the independent temperature controllers 68 of the remaining refrigeration systems 12 will automatically increase the speed of their compressors 56 over time to compensate for the lost cold. Thus, it is envisioned that the various technological elements of the vending machine 10' (e.g., multiple independent temperature control devices, variable speed compressors, top-loading refrigerators that do not occupy a cold volume, simple / non-specialized mechanical and electrical connections between the refrigeration system modules and the cabinet, etc.) will work together to repair the failed refrigeration system 12 without disrupting business.

[0094] Before installing an operational cooling system, the technician unblocks holes 30, 32. In some cases, the technician may be able to quickly repair the cooling system module 12 after removal to make it operational again. In such cases, the technician can reinstall the same cooling system module 12 into the cabinet module 11 after repair. In another embodiment, the technician installs an operational replacement cooling system module 12 in place of the failed system.

[0095] Again, no skilled tradesman is required to install an operational refrigeration system 12 on top of cabinet 11. Any technician can simply mechanically mount the system to the top wall using rails 90, as described above, plug power cord 154 into high-voltage receptacle 136 in main electrical box 124, and insert the previously disconnected cable into connector 152. The newly installed system's independent temperature controller 68 will then independently begin cooling the common refrigerated space. It will be appreciated that the illustrated refrigerated vending machine, with its entirely top-mounted refrigeration system and redundancy through multiple independent temperature controls, can be serviced without removing merchandise from the reach-in cabinet.

[0096] As can be seen, the illustrated refrigerated vending machine kit 10 is field-installable through a standard-height human-height entrance and, once deployed, provides a very high-capacity refrigerated vending machine 10'. The vending machine 10' maximizes packable space by locating all refrigeration elements outside the cabinet 11. Additionally, by providing an integrated condensate removal system 104, the vending machine 10' can be placed in a store without opening its rear to adjacent structures. Furthermore, the vending machine kit 10 can be installed and operated without specialized or certified personnel, such as a refrigeration engineer, plumber, or electrician. Even when multiple refrigeration system modules 12 are used to cool a very large common refrigerated space defined within the cabinet module 11, the entire installation process requires only the turning of a few screws and the insertion of the unit's electrical cord into a standard electrical receptacle along with a standard latching electrical connector. The ease of installation afforded by the illustrated field installable vending machine kit 10 is unmatched by any refrigerated cabinet of comparable dimensions known to the inventors.

[0097] These advantages are particularly useful if the vending machine 10 must be moved to another building or location. Conversely, using the same basic techniques, the refrigeration system module 12 can be separated from the cabinet module 11 without the need for a licensed contractor. The separated modules can then be moved through a standard-height human door to a new location, where the vending machine 10' can be relocated using the same techniques described above.

[0098] Kit 10 also allows for the combination of a sealed refrigeration system 12 with cabinet 11, providing greater interior capacity than conventional cabinets previously only possible with remote refrigeration systems. This substantially reduces the potential for refrigerant loss and is generally believed to improve installation, reliability, serviceability, and energy efficiency over conventional refrigerated vending machines of comparable size.

[0099] Additionally, the illustrated kit 10 offers the advantage of locating the entire refrigeration system 12 outside the cabinet interior, which significantly improves serviceability as no items need to be removed or removed from the cabinet to access any components of the refrigeration system for inspection or maintenance.

[0100] Certain exemplary embodiments of freezers, refrigerated vending machines, and field-installable refrigerated vending machine kits according to the present disclosure are configured to automatically equalize pressure between the interior and exterior of the cabinet. It is well known in the refrigeration industry that pressure differences between the interior and exterior of a refrigerated cabinet can have undesirable effects. For example, if the pressure inside the cabinet is lower than the pressure outside the cabinet, a vacuum will form at the door. If the door is well sealed, breaking the vacuum can be difficult. The force required to open the door can be excessive, resulting in less user-friendly vending machines than would be desired. Various methods have been proposed in the past to address this issue. For example, some proposals have incorporated door handle mechanisms that break a door seal when a user attempts to open the door. More generally, proposals have included incorporating pressure relief valve systems into refrigerated cabinets that passively act to automatically equalize pressure inside and outside the vending machine by opening in response to increasing pressure differentials between the interior and exterior of the cabinet.

[0101] While the inventors recognize the benefits of employing such pressure relief valve systems, they believe that current pressure relief valve systems have undesirable drawbacks. For example, the inventors believe that current pressure relief valve systems indiscriminately direct moist outside air onto the cooled interior surfaces of the vending machine, which over time results in frost buildup that is not easily repaired. Furthermore, existing pressure relief valve systems are not suitable for high-volume modular vending machine kits such as those described above because they are not adapted to account for the different air volumes and duty cycles of the various refrigerator cabinet modules. As described in more detail below, the inventors have developed a novel pressure relief valve system that addresses at least these issues by incorporating a heated pressure relief valve directly into the evaporator containment.

[0102] An exemplary embodiment of a freezer or refrigerated vending machine 10′ (broadly, a refrigerated storage device) according to the present disclosure includes a refrigeration system (e.g., a pre-fabricated refrigeration system module) generally designated 12′, shown separately from cabinet 11 in FIGS. 25-33 . Because a glass-door vending machine is the type of refrigerated storage or display device depicted above, the refrigerated storage device will often be referred to as a “vending machine” in this disclosure. However, it will be understood that the principles of the present disclosure can also be employed in other types of refrigerated storage or display devices, such as opaque-door freezers. A refrigerated storage device according to the present disclosure includes a door for enclosing the refrigerated storage space. As noted above, the refrigeration system 12′ may include a pre-fabricated refrigeration system module configured for operably connecting to cabinet module 11 on-site. In other words, a refrigerated storage device according to the present disclosure may include a field-installable modular kit of the type described above, although other types of refrigerated storage devices (e.g., non-modular, self-contained freezers) are also contemplated within the scope of the present disclosure.

[0103] Cooling system 12' is the same as cooling system 12, except for the additional pressure relief valve system described below. Accordingly, it should be understood that all elements of cooling system 12 described above are included in cooling system 12'. Where identical parts are described below, parts of cooling system 12' will be given the same reference numeral as the corresponding part in cooling system 12, followed by a prime symbol.

[0104] The cooling system 12' includes a pressure relief valve 210' configured to automatically open in response to the pressure inside the cabinet 11 being lower than the pressure outside the cabinet, thereby equalizing the pressure between the interior and exterior of the cabinet module. When the pressure relief valve 210' opens in this scenario, outside air (containing moisture) is admitted into the cooling system 12'. As described more fully below, the pressure relief valve system illustrated herein is configured to cool the incoming air as soon as it enters the cooling system module 12' through the pressure relief valve 210'. The proposed system effectively dehumidifies and ultimately freezes the moisture from the outside air within the cooling system module 12' because the air within the cooling system module is cooler than 32 degrees Fahrenheit. The cooler, drier air exits the cooling system 12' and is sent to the refrigerated vending machine 10'. By reducing the heat content of the outside air within the refrigeration system 12', thereby dehumidifying and freezing the moisture, the outside air entering through the pressure relief valve 210' is conditioned so as not to provide additional heat and moisture to the interior space of the refrigerated vending machine 10'.

[0105] In certain embodiments, pressure relief valve 210' is also configured to automatically open in response to pressure inside cabinet module 11 being greater than pressure outside the cabinet module. In this scenario, cool air from inside vending machine 10' flows out of the machine through valve 210' to equalize the pressure.

[0106] Valve 210' automatically closes when the pressures inside and outside cabinet 11 are substantially equal. Note that in the cross-sections of Figures 27-30, the internal components of valve 210' are not shown for clarity. Those skilled in the art will recognize that valve 10' comprises a valve body defining a valve passageway through which air can pass between the interior and exterior, and at least one adjustable valve member that is passively adjustable in response to a pressure differential to open or close the valve passageway.

[0107] In an exemplary embodiment, the pressure relief valve 210' is heated to prevent frost from forming inside the pressure relief valve. More specifically, the pressure relief valve 210' includes a dedicated valve heater 211' (shown schematically) configured to prevent frost from forming inside the pressure relief valve. Preferably, the pressure relief valve 210' includes an electrical resistance heater 211' disposed in thermal communication with the valve passage and valve member and configured to operate continuously or at a low wattage with a selectable duty cycle to prevent moisture in the air from forming frost anywhere inside the valve. The selectable duty cycle of the valve heater 211' is independent of the evaporator defrost cycle. In a preferred embodiment, the pressure relief valve 210' includes a heated pressure relief valve of the general type described in U.S. Pat. No. 10,731,912, which is incorporated herein by reference in its entirety. Other types of heated pressure relief valves may also be used without departing from the scope of this disclosure.

[0108] As described above, the refrigeration system 12' includes an evaporator enclosure 76' and an evaporator assembly 50' received within the evaporator enclosure. The evaporator enclosure 76' includes one or more insulating walls that thermally insulate the interior of the evaporator enclosure from the environment external to the vending machine 10'. Additionally, the evaporator enclosure 76' includes a supply air outlet 80' and a return air inlet 82' through which the evaporator assembly 50' moves refrigerated air in the manner described above. In one or more embodiments, at least one insulating wall of the evaporator enclosure 76' includes an insulating panel 220' and a sheet metal liner 222' that defines the interior surface of the evaporator enclosure. The illustrated refrigeration system 12' is configured to mount modularly on a separate cabinet module 11 (described above) and therefore includes insulating walls on all sides of the evaporator enclosure 76'. However, it will be understood that the present disclosure is not strictly limited to modular vending machine kits. Accordingly, in one or more embodiments, the present disclosure contemplates an evaporator enclosure received within a cabinet within the refrigerated space. In such an embodiment, the evaporator enclosure would also include at least one insulating wall; for example, the at least one insulating wall may constitute a section of the cabinet exterior wall adjacent the evaporator assembly. The evaporator enclosure suitably includes ports 80', 82' for drawing return air across the evaporator assembly and discharging refrigerated air into the vending machine's main storage space. As described more fully below, the pressure relief valve 210' is configured to be mounted to one insulating wall of the evaporator enclosure 76', hereinafter referred to as the "relief valve support wall" 230', such that the pressure relief valve is positioned proximate the evaporator assembly 50' and directed generally toward the evaporator, thereby directing outside air flowing through the pressure relief valve 210' toward the evaporator. When pressure relief valve 210' is opened and heat and moisture are processed in cooling system 12', conditioned air is placed in fluid communication between the interior of cabinet 11 and the exterior of the cabinet via ports 80', 82'.

[0109] The evaporator assembly 50' includes an evaporator coil 64' in which liquid refrigerant absorbs heat and converts to a vapor. The evaporator assembly 50' further includes an evaporator fan 66' configured to draw return air from the cabinet 11 across the evaporator coil 64' and cool the air before discharging the cooled air into the cabinet. In one or more embodiments, the evaporator assembly 50' further includes a plurality of heat transfer fins 233' disposed across the evaporator coil 64'. In the illustrated embodiment, the heat transfer fins 233' are capped by first and second end plates 212' disposed at opposite end portions of the evaporator coil 64'. The evaporator coil 64' has a hairpin-back turn-to-turn coil width CW, a coil height CH, and a coil depth CD. The evaporator enclosure 76' has an inner enclosure width IEW extending across the coil, an inner enclosure height IEH extending across the coil, and an inner enclosure depth IED extending across the coil. The inner containment width IEW, inner containment height IEH, and inner containment depth IED are greater than the coil width CW, coil height CH, and coil depth CD, respectively, so that the evaporator coil 64' fits within the evaporator containment.

[0110] One insulation wall of the evaporator enclosure 76′ includes a relief valve support wall 230′. In the exemplary embodiment, the relief valve support wall 230′ extends in a plane generally parallel to the coil height CH and the coil depth CD, although this is not strictly required. The relief valve support wall 230′ defines a relief valve hole 232′ for receiving the pressure relief valve 210′. The relief valve hole 232′ extends through the entire thickness of the relief valve support wall 230′, forming a passageway through the insulation panel 220′ and the sheet metal liner 222′. The relief valve hole 232′ is aligned with the evaporator assembly 50′ such that the relief valve hole accommodates the pressure relief valve 210′ for directing ambient air to the evaporator assembly when the pressure relief valve automatically opens in response to pressure inside the cabinet module being lower than pressure outside the cabinet module. The relief valve hole 232′ is oriented so that the pressure relief valve 210′ has a flow axis FA along which ambient air flows through the relief valve and into the evaporator containment chamber 76′. In the illustrated embodiment, the flow axis FA is generally parallel to the coil width CW, generally intersects a lower section (e.g., the lower half or lower third) of the coil height CH, and generally intersects a central portion (e.g., the central third) of the coil depth CD. It will be appreciated that the pressure relief valve may have other locations without departing from the scope of this disclosure. The inventors specifically contemplate relocating the relief valve hole 232′ further upstream so that the flow axis FA intersects an upstream section (e.g., the upstream half or upper third) of the coil depth CD to better facilitate interaction between the air entering the valve 210′ and the evaporator (thereby facilitating better preconditioning of the air) before the air is discharged through the supply air outlet 80′. As will be explained more fully below, the illustrated cooling system 12' includes a baffle adjacent the valve outlet that redirects air entering along flow axis FA to flow depthwise toward port 82' before reversing course across coil 64' toward outlet port 80'. Thus, in Figure 29, the inventors contemplate positioning the valve upward on the page (when the page is viewed in its proper landscape orientation) in the upstream section of coil depth CD.Locating the relief valve hole 232′ in the lower section of the coil height CH may be advantageous because warm ambient air tends to rise as it enters the cold space within the cooling system 12′. Locating the relief valve 210′ lower along the coil height CH may promote more interaction between the air entering through the valve 210′ and the evaporator 50′ (thereby promoting more pre-conditioning of the air) before the air is discharged through the supply air outlet 80′.

[0111] The cooling system 12' includes a frosting chamber 242' within the evaporator enclosure 76'. The frosting chamber 242' is immediately adjacent to the evaporator assembly 50' such that the frosting chamber is cooled by the evaporator assembly. In the illustrated embodiment, the frosting chamber 242' and the evaporator assembly 50' are aligned in the direction of the coil width CW. The illustrated frosting chamber 242' includes three sides defined by the evaporator assembly end plate 212' (facing the pressure relief valve 210'), the sheet metal liner 222' of the relief valve support wall 230', and a metal span wall 243' spanning between the evaporator assembly end plate and the relief valve support wall. The metal span wall 243' includes a first vertical edge margin secured to the relief valve support wall 230' and an opposite second vertical edge margin secured to the end plate 212'. The metal end plate 212' and the sheet metal liner 222' define opposite sides of the frosting chamber 242', and the metal spun wall 243' defines a third side of the frosting chamber 242' transverse to the two opposite sides. Thus, the sheet metal liner 222', the metal spun wall 243', and the end plate 212' together define three continuous, generally rectangular sides of the frosting chamber. The metal spun wall 243' and the evaporator assembly end plate 212' form a baffle to redirect incoming air along the flow axis FA to flow depthwise toward the port 82'.

[0112] A fourth side of the frosting chamber 242' (or a portion of one of the chamber's four sides) is preferably open to define an open side outlet 244' that allows outside air to exit the frosting chamber after the moisture has been frosted within the chamber. In the illustrated embodiment, the top wall of the evaporator enclosure 76' substantially surrounds the top of the frosting chamber 242', and the evaporator drain pan 106' is located immediately below the bottom of the frosting chamber such that the path of least resistance for outside air to exit the frosting chamber 242' is through the open side outlet 244'. Thus, in the illustrated embodiment, the frosting chamber 242' (particularly the baffle formed by the walls 212', 243') is configured to direct a majority of the outside air entering through the pressure relief valve 210' to exit the frosting chamber through the open side outlet 244'. Here, the open side outlet 244' defines the side of the frosting chamber 242' opposite the span wall 243'.

[0113] The open side outlet 244' is also located at the upstream end of the frosting chamber 242' in the direction of refrigerated air flow across the evaporator assembly 50'. As explained above, the evaporator fan 66' is configured to draw return air through the return air port 82' and exhaust air through the supply air port 80'. Thus, the direction of refrigerated air flow across the evaporator runs generally parallel to the coil depth CD in a direction extending from the return air port 82' to the supply air port 80'. The open side outlet 244' is spaced from the span wall 243' of the frosting chamber 242' in an upstream direction relative to refrigerated air flow across the evaporator coil 64'. Thus, outside air exits the frosting chamber 242' through the open side outlet 244' upstream of the evaporator coil 64', where it can be drawn across the evaporator coil by the fan 66'. Fresh air entering along flow axis FA first turns approximately 90° in the width-depth plane toward outlet 244′ through the baffle, then turns approximately 180° in the depth-width plane to flow across coil 64′ as propelled by the evaporator fan.

[0114] Because the frosting chamber 242' is cooled by the evaporator assembly 50', the frosting chamber provides a cooled interior frosting surface on which moisture in the ambient air channeled into the vending machine through the pressure relief valve 210' freezes as frost. In the illustrated embodiment, the sheet metal liner 222', metal end plate 212', and metal span wall 243' each define a respective side of the cooled interior frosting surface. The metal end plate 212' defines a first side of the cooled frosting surface facing the outlet of the pressure relief valve 210'. The metal end plate 212', and therefore the first side of the cooled frosting surface, extends in a plane parallel to the coil height CH and the coil depth CD and has a height equal to or greater than the coil height CH and a width equal to or greater than the coil depth CD. The metal liner 222' defines a second side of the cooled frosting surface opposite the first side. The metal liner 222', and thus the second side of the cooled frosted surface, extends in a plane parallel to the coil height CH and the coil depth CD and has a height equal to or greater than the coil height CH and a width equal to or greater than the coil depth CD. The metal span wall 243' forms a third side of the cooled frosted surface that is perpendicular (broadly lateral) to the first and second sides. The metal span wall 243', and thus the third side of the cooled frosted surface, has a height equal to or greater than the coil height CH and spans the gap between the first and second sides of the cooled frosted surface. It can thus be seen that the cooled frosted surface generally defines a three-sided chamber 242' laterally of the evaporator assembly 50' that spans the entire height CH and depth CD of the evaporator coil 64'. Thus, in one or more embodiments, the frosted chamber 242' has a chamber height CHH equal to or greater than the coil height and a chamber depth CHD equal to or greater than the coil depth CD. Each of the metal end plate 212', metal inner surface 222', and metal spanning wall 243' extends to the full chamber height CHH.

[0115] During normal use, the evaporator assembly 50' cools the cooled frosting surface to a freezing temperature (e.g., a temperature below 0°C). When the pressure relief valve 210' opens and moist ambient air enters the vending machine 10', the air first contacts the cooled frosting surface, causing a portion of the moisture to freeze as frost on the cooled frosting surface. The baffle is configured to deflect the air from the valve 210', which creates a degree of turbulence that promotes interaction with the cooled frosting surface. The inventors believe that increased interaction with the cooled frosting surface promotes the moisture in the air freezing as frost on the cooled frosting surface. For example, moist ambient air flows generally along the flow axis FA into the frosting chamber 242' and contacts the end wall 212' of the evaporator assembly 50'. A portion of the moisture in the air freezes as frost on the inner surface of the end wall 212'. A portion of the air is deflected from the end wall 212' toward the opposing sheet metal liner 222', where more moisture freezes as frost. Other air is deflected from one or both of the end plate 212' and liner 222' toward the span wall 243', where more moisture freezes as frost. A portion of the air is repeatedly deflected from various sides of the cooled frosted surface, thereby gradually removing moisture from the air as frost on the cooled interior frosted surface. Finally, outside air exits the frosting chamber primarily through the open side outlet 244'. As the evaporator fan 66' draws air from the frosting chamber outlet 244' across the evaporator coil, additional moisture from the air can further freeze as frost on the evaporator coil 64' and fins 233'.

[0116] It can be seen that the frosting chamber 242' removes a significant amount of moisture from the outside air before it reaches the rest of the refrigerated vending machine 10'. Furthermore, because the frosting chamber 242' directs much of the outside air to flow across the evaporator coil 64' before interacting with other portions of the vending machine 10', more of the moisture in the air freezes as frost on the coil and fins 233'. The inventors believe this arrangement is beneficial because it reduces the amount of frost that forms in other portions of the vending machine (e.g., the interior storage space or refrigerated goods). In one or more embodiments, the pressure relief valve 210' is configured to direct outside air through the frosting chamber 242' into the interior of the cabinet such that a majority of the moisture in the outside air introduced through the pressure relief valve freezes within the cooling system 12' as frost on the cooled interior frosted surfaces of the frosting chamber.

[0117] As described above, the prefabricated refrigeration system 12' includes a defrost heater 172' and an evaporator drain pan 106'. The evaporator drain 106' includes a first section 106A' below the evaporator assembly and a second section 106B' below the frosting chamber 242'. The drain pan 106' has a width DW greater than the coil width CW' so that the evaporator drain pan can receive melted water from both the evaporator coil 64' and the frosting chamber 242'. In the illustrated embodiment, the defrost heater 172' is positioned directly below the evaporator coil 64' and has a width equal to or greater than the coil width CW. The defrost heater 172' can overlap the frosting chamber 242' in the width direction.

[0118] The vending machine 10' is configured to periodically perform defrost cycles in which the defrost heater 172' melts frost formed on the evaporator coil 64'. During each defrost cycle, the heat generated by the defrost heater 172' also melts frost formed in the frosting chamber 242'. In other words, the frosting chamber 242' is positioned relative to the defrost heater 172' such that frost formed on the cooled, frosted interior surface during the defrost cycle is defrosted and drained into the evaporator drain pan 106'. Because the evaporator drain pan 106', like the evaporator coil 64', is located below the frosting chamber 242', frost melted from the frosting chamber 242' during each defrost cycle is drained through the evaporator drain pan 106' and evaporated using the condensate removal system described above.

[0119] Thus, in one aspect, the present disclosure provides a refrigerated vending machine or freezer that includes an evaporator with automatic defrosting, a heated pressure relief valve, and a frosting chamber strategically located between the pressure relief valve and the evaporator, such that a majority of the moisture in the outside air entering the machine through the pressure relief valve forms frost on the cooled surfaces of the frosting chamber and on the evaporator, where it can be easily removed during regular defrost cycles. A dedicated valve heater prevents frost from forming within the pressure relief valve, ensuring that the valve is always operational. The frosting chamber also collects frost where it can be easily removed by the defrosting heater and condensate removal system. Thus, the present disclosure addresses undesirable pressure differentials between the interior and exterior of the cabinet without creating significant frosting issues within the cabinet and on the refrigerated vending machine.

[0120] In another aspect, the present disclosure provides an elegant method for outfitting a high-capacity modular refrigerated vending machine 10' with a desired amount of pressure equalization capacity for equalizing pressure between the interior and exterior of the machine. Conventional pressure relief valve systems are mounted in the refrigeration cabinet. However, the inventors have recognized that by locating the pressure relief valve in a pre-fabricated refrigeration system module rather than in the cabinet module, fabrication and inventory of the modular vending machine system can be streamlined.

[0121] As described above, certain embodiments of cabinet modules 11 are configured to operatively connect to a plurality of prefabricated cooling system modules 12'. These cabinets 11 include a plurality of pairs of ports, each pair including one supply air inlet 30 and one return air outlet 32. Each pair of ports 30, 32 corresponds to the mounting location of one prefabricated cooling system module 12'. A vending machine 10' is formed from the kit 10 by mounting a prefabricated cooling system module 12' to the top of the cabinet at each pair of ports 30, 32.

[0122] The number of pairs of ports 30, 32 formed in the cabinet module 11 is a function of the interior volume of the cabinet module. Each pre-fabricated cooling system module 12' has a cooling capacity rating, and the number of pairs of ports 30, 32 is selected so that the combined cooling system module 12' provides the desired amount of cooling to the vending machine 10'.

[0123] The inventors have recognized that just as the required cooling capacity scales proportionally with the internal cabinet volume, the negative pressure differential between the interior and exterior of cabinet 11 affects the force required to open door 22 proportionally with the internal cabinet volume. That is, all other things being equal, for a given negative pressure differential, the larger the internal volume of cabinet 11, the greater the force required to open door 22. Therefore, the inventors believe it is important to scale the pressure relief capacity proportionally with the internal cabinet volume.

[0124] The inventors believe that locating the pressure relief valves 210' on the prefabricated cooling system modules 12' rather than on the cabinet 11 provides an elegant way to ensure that pressure relief capacity is always sufficient for a modular refrigerated vending machine of any size. Each cabinet module 11 is provided with a number of port 30, 32 pairs corresponding to the number of prefabricated cooling system modules 12' that provide sufficient cooling capacity for the cabinet. By locating the pressure relief valves 210' on the prefabricated cooling system modules 12', whenever a required number of prefabricated cooling system modules are installed on the cabinet module 11, a required number of pressure relief valves 210' are simultaneously installed on the vending machine 10'. Once installed, each pressure relief valve 210' is configured to open in response to pressure inside the refrigerated vending machine cabinet 11 being lower than pressure outside the refrigerated vending machine cabinet, thereby allowing the pressure relief valves of the multiple cooling systems 12' to equalize pressure inside the refrigerated vending machine cabinet with pressure outside the refrigerated vending machine cabinet. Thus, the required number of prefabricated cooling system modules 12' can be installed in the cabinet module 11 to automatically provide sufficient pressure equalization capacity.

[0125] Manufacturers do not need to manufacture and maintain an inventory of cabinet modules with different numbers of pressure relief ports. This is advantageous because the same cabinet module 11 can be used for different cooling applications by simply selecting the pre-fabricated cooling system module 12, 12' desired for a given application. For example, if the vending machine is used solely as a fresh food refrigerator, a pressure relief system may not be necessary. An appropriately sized cabinet module 11 can be coupled to one or more pre-fabricated fresh food cooling system modules 12, which may not have pressure relief valves. The assembled vending machine 10' does not have any pressure relief valves because they are not needed for that application. However, the same cabinet module 11 could also be used to hold frozen foods, such as ice cream, for which a pressure relief system is desired. A cooling system module 12' including a pressure relief valve 210' can be installed in the same cabinet module 11' to provide the desired pressure relief capability for the frozen food application.

[0126] When introducing elements of the present invention or preferred embodiments thereof, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of such elements. The words "comprising," "including," and "having" are intended to be inclusive and mean that there may be elements other than the listed elements.

[0127] In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

[0128] It is intended that all matter in the foregoing specification be taken in an illustrative and not a limiting sense, as various changes may be made in the vending machine and method described above without departing from the scope of the present invention.

Claims

1. A field-installable refrigerated vending machine kit, comprising: a cabinet module having an exterior and an interior; an off-the-shelf cooling system module configured to operably connect to the cabinet module for cooling the interior; Including, the off-the-shelf cooling system module is separate from the cabinet module; the off-the-shelf cooling system module and the cabinet module comprising interconnect fittings configured to removably and operably connect the off-the-shelf cooling system module to the cabinet module for cooling an interior of the cabinet module; the prefabricated cooling system module includes a pressure relief valve configured to automatically open in response to a pressure inside the cabinet module being lower than a pressure outside the cabinet module, whereby the pressure relief valve is configured to equalize pressure between the interior and exterior of the cabinet module. Refrigerated vending machine kit that can be installed on-site.

2. 10. The field installable refrigerated vending machine kit of claim 1, wherein the pressure relief valve is heated to prevent frost from forming inside the pressure relief valve.

3. 10. The field-installable refrigerated vending machine kit of claim 1, wherein the pressure relief valve comprises an electrical resistance heater configured to operate at 100% or a user-selected duty cycle.

4. 10. The field installable refrigerated vending machine kit of claim 1, wherein the pre-fabricated refrigeration system module comprises an evaporator assembly and an evaporator enclosure, the evaporator assembly being received within the evaporator enclosure.

5. 5. The field installable refrigerated vending machine kit of claim 4, wherein the evaporator enclosure includes an insulated wall defining a pressure relief valve aperture for receiving the pressure relief valve.

6. 6. The field-installable refrigerated vending machine kit of claim 5, wherein the pressure relief valve is aligned with the evaporator assembly to direct outside air toward the evaporator assembly when the pressure relief valve automatically opens in response to pressure inside the cabinet module being lower than pressure outside the cabinet module.

7. 7. The field-installable refrigerated vending machine kit of claim 6, wherein the prefabricated refrigeration system module comprises a frosting chamber within the evaporator enclosure, the frosting chamber being cooled by the evaporator assembly and comprising a cooled interior frosting surface on which moisture in the outside air freezes as frost.

8. 8. The field-installable refrigerated vending machine of claim 7, wherein the insulated wall of the evaporator comprises a sheet metal liner and the evaporator assembly comprises metal end plates, the sheet metal liner and the metal end plates defining opposite sides of the cooled interior frosting surface.

9. 9. The field-installable refrigerated vending machine of claim 8, wherein the prefabricated cooling system module comprises metal spun walls coupled to the sheet metal liners and end plates and defining lateral sides of the cooled interior frosted surface.

10. 10. The field installable refrigerated vending machine of claim 9, wherein the evaporator assembly comprises an evaporator coil, the evaporator coil having a coil height, and the frosting chamber having a chamber height equal to or greater than the coil height.

11. 11. The field installable refrigerated vending machine of claim 10, wherein the metal span wall extends the entire height of the frosting compartment.

12. 8. The field-installable refrigerated vending machine of claim 7, wherein the evaporator assembly comprises an evaporator coil, and the prefabricated refrigeration system module further comprises an evaporator drain pan below the evaporator coil and the frosting chamber.

13. 13. The field installable refrigerated vending machine of claim 12, wherein the evaporator coil has a coil width and the drain pan has a pan width that is greater than the coil width.

14. 13. The field-installable refrigerated vending machine of claim 12, wherein the evaporator assembly further comprises a defrost heater configured to periodically perform a defrost cycle, whereby the defrost heater melts frost formed on the evaporator coil and within the frosting chamber.

15. 1. A method of providing a refrigerated storage cabinet with pressure equalization capacity sufficient to equalize pressure between an interior and an exterior of the refrigerated storage cabinet, comprising: providing a plurality of pairs of supply air inlets and return air outlets in the refrigerated enclosure cabinet; providing a plurality of cooling systems configured to be operably connected to the refrigerated storage cabinet for cooling the interior, each cooling system comprising a pressure relief valve configured to automatically open in response to a pressure differential across the pressure relief valve; mounting each of the plurality of cooling systems to the refrigerated storage cabinet such that each cooling system is configured to cool the refrigerated storage cabinet by providing cold air within the cabinet and drawing return air from the cabinet, and such that each pressure relief valve is configured to open in response to pressure inside the refrigerated storage cabinet being lower than pressure outside the refrigerated storage cabinet, whereby the pressure relief valves of the plurality of cooling systems equalize pressure inside the refrigerated storage cabinet with pressure outside the refrigerated storage cabinet; A method comprising:

16. 1. A refrigerated storage or display device comprising: a cabinet having an interior and an exterior; an evaporator containment vessel, the evaporator containment vessel comprising a thermal insulation wall separating an interior of the evaporator containment vessel from an exterior thereof, the thermal insulation wall defining an opening for a pressure relief valve; a refrigeration system for cooling an interior of the cabinet, the refrigeration system including an evaporator assembly within the evaporator enclosure; a frosting chamber within the evaporator enclosure between the insulating wall and the evaporator assembly, the frosting chamber having a cooled interior frosting surface, the frosting chamber being immediately adjacent to the evaporator assembly such that the frosting chamber is cooled by the evaporator assembly; an evaporator drain pan located below the evaporator assembly and the frosting chamber; a pressure relief valve within the pressure relief valve opening, the pressure relief valve including a valve heater configured to heat the pressure relief valve to prevent frost from forming inside the pressure relief valve, the pressure relief valve configured to open in response to a pressure inside the cabinet being lower than a pressure outside the cabinet, whereby moisture laden outside air is introduced through the pressure relief valve into the cooling system and then into the cabinet until the pressure inside the cabinet equals the pressure outside the cabinet, and the pressure a pressure relief valve configured to direct the outside air through the frosting chamber into the interior of the cabinet, whereby moisture in the outside air introduced through the pressure relief valve freezes as frost on the cooled interior frosting surface of the frosting chamber; and a defrost heater configured to periodically perform a defrost cycle to defrost the evaporator, the frosting chamber being positioned relative to the defrost heater so that frost formed on the cooled interior frosting surface is defrosted and discharged into the evaporator drain pan during the defrost cycle. A refrigerated storage or display device comprising:

17. 17. The refrigerated storage or display unit of claim 16, wherein the evaporator assembly and the frosting chamber are side-by-side.

18. 18. The refrigerated storage or display device of claim 17, wherein the evaporator drain pan includes a first section below the evaporator assembly and a second section below the frosting compartment.

19. 17. The refrigerated storage or display device of claim 16, wherein the evaporator assembly comprises a metal end plate, the insulating wall includes a metal inner surface, and the refrigerated vending machine further comprises a metal spunbond wall between the metal inner surface and the metal end plate, the metal end plate, the metal inner surface, and the metal spunbond wall defining at least a portion of the cooled inner frosted surface.

20. 20. The refrigerated storage or display device of claim 19, wherein the evaporator assembly comprises an evaporator coil having a coil height, the frosting chamber comprises a chamber height equal to or greater than the coil height, and each of the metal end plates, the metal interior surface, and the metal span wall extends across the entire chamber height.

21. 1. A refrigerated storage or display device comprising: a cabinet having an interior and an exterior; a cooling system for cooling an interior of the cabinet, the cooling system including an evaporator and an evaporator fan configured to move air in the cabinet in a flow direction across the evaporator; a pressure relief valve configured to open in response to a pressure inside the cabinet being lower than a pressure outside the cabinet, thereby allowing moisture-laden ambient air to pass through the pressure relief valve into the cooling system and then into the interior of the cabinet until the pressure inside the cabinet equals the pressure outside the cabinet; and a baffle between the pressure relief valve and the evaporator, the baffle being cooled by the evaporator, the baffle being configured to redirect air entering the refrigerated storage or display device through the pressure relief valve, such that the air entering the refrigerated storage or display device flows along the baffle in a direction different from the flow direction before flowing in the flow direction across the evaporator; and 1. A refrigerated storage or display device comprising:

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