Title:
Modular refrigeration cassette
Kind Code:
A1


Abstract:
The interior space within a refrigeration unit cassette (50) associated with a refrigerated merchandiser (10) is divided by a division wall (68) into a first section in air flow communication with the interior product display space of the cabinet (20), and a second section isolated from said first section and in fluid flow communication with the environment exterior of the cabinet. An evaporator module (160) disposed within the first section, and a condenser module (170) and a compressor are disposed within the second section. The refrigeration cassette (50) is selectively insertable in to and out of the equipment compartment to facilitate servicing of the refrigeration equipment therein, including removal and replacement of the evaporator module (160) and the condenser module (170).



Inventors:
Mead, Brian J. (Liverpool, NY, US)
Daddis Jr., Eugene Duane (Manlius, NY, US)
Daniels, Mark A. (Manlius, NY, US)
Clark, Daniel R. (Fayetteville, NY, US)
Application Number:
11/358833
Publication Date:
09/21/2006
Filing Date:
02/21/2006
Assignee:
Carrier Corporation (Farmington, CT, US)
Primary Class:
Other Classes:
62/448
International Classes:
A47F3/04; F25D19/02
View Patent Images:



Primary Examiner:
TAPOLCAI, WILLIAM E
Attorney, Agent or Firm:
MARJAMA MULDOON BLASIAK & SULLIVAN LLP (SYRACUSE, NY, US)
Claims:
We claim:

1. A refrigeration cassette for a refrigerated merchandiser having a cabinet having a refrigerated interior space for housing a product in a refrigerated environment intended for selection by consumers, said refrigeration cassette disposed in operative association with the interior space in an equipment compartment separated from the refrigerated interior space by a common wall, the common wall having a first opening therein providing air flow communication between the refrigerated interior space and the equipment compartment; said refrigeration cassette comprising: a generally box-like structure defining an interior space having a first section in air flow communication with said first opening, and a second section isolated from said first section and in fluid flow communication with the environment exterior of the cabinet; an evaporator module disposed within said first section; a condenser module disposed within said second section; and a compressor connected in refrigerant flow communication with said evaporator module and said condenser module for circulating refrigeration through said evaporator module and said condenser module; said box-like structure being selectively insertable in to and out of the equipment compartment.

2. A refrigeration cassette as recited in claim 1 wherein said evaporator module includes a housing, an evaporator coil disposed within the housing, and an evaporator fan/motor assembly operatively associated with the evaporator coil and mounted to the housing.

3. A refrigeration cassette as recited in claim 1 wherein said condenser module includes a condenser coil and a condenser fan/motor assembly operatively associated with the condenser coil.

4. A refrigeration cassette as recited in claim 1 further comprising a liner disposed within said first section of the interior space of said box-like structure; said liner including a bowl-like depression adapted to receive said evaporator module.

5. A refrigeration cassette as recited in claim 4 wherein said liner includes a downwardly sloping tray-like forward portion and an aft portion having a bowl-like depression.

6. A refrigeration cassette as recited in claim 5 wherein said liner has contoured surfaces to reduce airflow losses.

7. A refrigeration cassette as recited in claim 4 wherein said liner is made of a material having a relatively high chemical resistance.

8. A refrigeration cassette as recited in claim 4 wherein said liner is made of a plastic material.

9. A refrigeration cassette for a refrigerated merchandiser having a cabinet having a refrigerated interior space for housing a product in a refrigerated environment intended for selection by consumers, said refrigeration cassette disposed in operative association with the interior space in an equipment compartment separated from the refrigerated interior space by a common wall, the common wall having a first opening therein providing air flow communication between the refrigerated interior space and the equipment compartment; said refrigeration cassette comprising: a generally box-like structure a front plate, a back plate, a pair of side plates and a base plate collectively defining an interior space; a division wall extending between the respective side plates of said pair of side plates to divide the interior space within said box-like structure into a first section in air flow communication with said first opening, and a second section isolated from said first section and in fluid flow communication with the environment exterior of the cabinet; an evaporator module disposed within said first section; a condenser module disposed within said second section; and a compressor connected in refrigerant flow communication with said evaporator module and said condenser module for circulating refrigeration through said evaporator module and said condenser module; said box-like structure being selectively insertable in to and out of the equipment compartment.

10. A refrigeration cassette as recited in claim 9 wherein said evaporator module includes a housing, an evaporator coil disposed within the housing, and at least one evaporator fan/motor assembly operatively associated with the evaporator coil and mounted to the housing.

11. A refrigeration cassette as recited in claim 9 wherein said condenser module includes a condenser coil and a condenser fan/motor assembly operatively associated with the condenser coil.

12. A refrigeration cassette as recited in claim 9 further comprising a liner disposed within said first section of the interior space of said box-like structure; said liner including a bowl-like depression adapted to receive said evaporator module.

13. A refrigeration cassette as recited in claim 9 wherein said liner includes a downwardly sloping tray-like forward portion and an aft portion having a bowl-like depression.

14. A refrigeration cassette as recited in claim 13 wherein said liner has contoured surfaces to reduce airflow losses.

15. A refrigeration cassette as recited in claim 12 wherein said liner is made of a material having a relatively high chemical resistance.

16. A refrigeration cassette as recited in claim 12 wherein said liner is made of a plastic material.

17. A refrigerated merchandiser having a refrigerated interior space, comprising: a cabinet having a plurality of walls defining the interior space; a refrigeration unit compartment separated from the interior space by one of the plurality of cabinet walls as a common wall; an opening in the common wall providing an air return inlet establishing a flow passage from the interior space through said common wall into the compartment; a refrigeration cassette selectively positionable into and out of the refrigeration unit compartment, said refrigeration cassette having a front plate, a back plate, a pair of side plates and a base plate forming a box-like structure defining an interior space, and having a division wall dividing the interior space into a first section in air flow communication with the air return inlet and a second section isolated from said first section and in fluid flow communication with an environment exterior of the cabinet; an evaporator module disposed within said first section; a condenser module disposed within said second section; and a compressor connected in refrigerant flow communication with said evaporator module and said condenser module for circulating refrigeration through said evaporator module and said condenser module.

18. A refrigerated merchandiser as recited in claim 17 wherein said evaporator module includes a housing, an evaporator coil disposed within the housing, and at least one evaporator fan/motor assembly operatively associated with the evaporator coil and mounted to the housing.

19. A refrigerated merchandiser as recited in claim 18 wherein said condenser module includes a condenser coil and a condenser fan/motor assembly operatively associated with the condenser coil mounted to a common base adapted to be mounted to the base plate of said refrigeration cassette.

20. A refrigeration merchandiser as recited in claim 17 wherein said evaporator module includes a housing, an evaporator coil disposed within the housing, and a plurality of evaporator fan/motor assemblies operatively associated with the evaporator coil and mounted to the housing.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser. No. 60/663,112, filed Mar. 18, 2005, and entitled MODULAR REFRIGERATION CASSETTE DESIGN FOR USE IN REFRIGERATED MERCHANDISER, which application is incorporated herein in its entirety by reference.

This application is related to the following applications subject to assignment to the common assignee of this application and filed with the United States Patent and Trademark Office on the same date as this application:

  • U.S. patent application Ser. No. ______ (Attorney Docket No. 210817NP), entitled “REFRIGERATED MERCHANDISER”;
  • U.S. patent application Ser. No. ______ (Attorney Docket No. 210816NP), entitled “SEALING SYSTEM FOR REFRIGERATION CASSETTE”;
  • U.S. patent application Ser. No. ______ (Attorney Docket No. 210879NP), entitled “MODULAR REFRIGERATION CASSETTE WITH CONDENSATE EVAPORATIVE TRAY”;
  • U.S. patent application Ser. No. ______ (Attorney Docket No. 210818NP), entitled “BOTTOM DECK ASSEMBLY FOR REFRIGERATED MERCHANDISER”; and
  • U.S. patent application Ser. No. ______ (Attorney Docket No. 210819NP), entitled “EVAPORATOR FAN/MOTOR ASSEMBLY MOUNTING BRACKET”. Each of the afore-listed patent applications is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to refrigerated merchandisers in general and, more particularly, to a refrigerated merchandiser including a refrigeration unit stowed in a compartment separate from the refrigerated interior product space of the refrigerated cabinet.

BACKGROUND OF THE INVENTION

Refrigerated merchandisers have a refrigeration system associated therewith for providing the cooled environment within a refrigerated interior product space defined within the cabinet of the refrigerated merchandiser. The refrigeration systems of such refrigerated merchandisers commonly employ a conventional refrigeration cycle and include an evaporator and an evaporator fan operatively associated with the refrigerated interior product space of the refrigerated cabinet, as well as a condenser, a condenser fan, and compressor. In stand alone cabinets, the compressor, condenser and condenser fan are housed in an equipment compartment separate from and insulated from the refrigerated interior product space of the refrigerated cabinet. Refrigerant lines connect the compressor, the condenser, and the evaporator in a conventional manner to form a closed circuit. A refrigerant is circulated by the compressor through the condenser and the evaporator before returning to the compressor. Air within the insulated refrigerated interior product space of the refrigerated cabinet is circulated by the evaporator fan through the evaporator in heat exchange relationship with the refrigerant so as to cool the air. The evaporator and evaporator fan may be disposed within the cooled interior of the refrigerated cabinet, for example in the upper region thereof.

However, it is well-known that the evaporator and evaporator fan may also be housed in the equipment compartment in a section of the equipment compartment insulated from the compressor, condenser and condenser fan. Among other uses, refrigerated merchandisers of this type may be used as product display cabinets for refrigerated or frozen foods, as vending machines, and as cold beverage merchandisers in supermarkets, grocery stores, gas stations, convenience stores, and other retail establishments. For example, cold beverages, such as soft drinks, beer, wine coolers, etc. are commonly displayed in refrigerated merchandisers for self-service purchase by customers. Conventional beverage merchandisers of this type include an insulated cabinet defining a refrigerated interior product display space having one or more glass doors that provide access to that product display space. The beverage product, typically in cans or bottles, single or in six-packs, is stored on shelves within the refrigerated display space of the cabinet. To purchase a beverage, the customer opens one of the doors and reaches into the refrigerated cabinet to retrieve the desired product from the shelf.

Refrigerated merchandisers equipped with refrigeration units disposed beneath the refrigerated cabinet are disclosed, for example, by Rudick et al. in U.S. Pat. Nos. 5,347,827; 5,402,654; 5,417,079; and 5,417,081. In these refrigerated merchandisers, the refrigerated air from the refrigeration unit flows up from the equipment compartment through a flow duct along the back wall of the cabinet, along the top wall of the cabinet toward the front of the cabinet and down the front of the cabinet to the floor of the product display zone. Refrigerated air may also enter the product display zone from the rear flow duct through a plurality of openings in the panel separating the flow duct from the product display zone. The refrigerated air from the product display zone returns to the equipment compartment, entering thereto upstream of the evaporator refrigeration unit through an air return inlet opening through the cabinet floor.

The refrigeration unit disclosed therein includes an evaporator, condenser and compressor collectively arranged on a base supported on a plurality of skids affixed to the bottom of the base. The compressor and condenser are positioned on the front portion of the base, and are separated from the evaporator by an insulated vertical partition disposed therebetween. The evaporator is disposed atop an evaporator pan which collects water condensed from the air passing through the evaporator. The collected water drains out of the evaporator pan into a shallow condenser pan located on the floor of the base in the exhaust path of the condenser fan whereby hot air exhausting from the condenser passes over the condenser pan and evaporates the water collected therein.

In refrigerated merchandisers having air passageways in the wall separating the refrigerated interior product space from the equipment compartment, undesired spill liquids and other contaminants may enter the refrigeration unit during operation, service or transportation. Spilled liquids draining into the refrigeration unit from the product display zone through the air inlet opening may foul or otherwise damage refrigerant unit components such as the evaporator heat exchanger coils, motors and fans. Spilled liquids could also damage surfaces bounding the airflow path through the refrigeration unit. Liquid spills could originate from product breakage within the product display zone, cleaning and maintenance operations, or condensation.

The need exists for a refrigeration cassette wherein the cassette is adapted to handle spilled liquids and condensate without damage to refrigeration unit components or surfaces. The refrigeration cassette should also accommodate and facilitate the use of modular refrigeration unit components.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a refrigeration cassette having improved reliability and serviceability.

It is an object of an aspect of the invention to provide a refrigeration cassette adapted to drain liquid spills away from damage susceptible refrigeration unit components.

It is an object of an aspect of the invention to provide a refrigeration cassette incorporating a liner with contoured surfaces for improved airflow.

It is an object of an aspect of the invention to provide a refrigeration cassette incorporating a liner formed of a material with improved chemical resistance.

It is an object of an aspect of the invention to provide a refrigeration cassette adapted to accommodate and facilitate the use of modular refrigeration unit components.

A modular refrigeration cassette is provided for a refrigerated merchandiser having a cabinet having a refrigerated interior space for housing a product in a refrigerated environment intended for selection by consumers. The refrigeration cassette is disposed in operative association with the interior space in an equipment compartment separated from the refrigerated interior space by a common wall. The common wall has a first opening therein providing air flow communication between the refrigerated interior space and the equipment compartment. The refrigeration cassette includes a generally box-like structure defining an interior space having a first section in air flow communication with said first opening, and a second section isolated from said first section and in fluid flow communication with the environment exterior of the cabinet. In an embodiment. The box-like structure includes a front plate, a back plate, a pair of side plates and a base plate collectively defining an interior space, and a division wall extending between the respective side plates divide the interior space within said box-like structure into the respective first and second sections. An evaporator module disposed within the first section. A condenser module and a compressor are disposed within the second section. The compressor is connected in refrigerant flow communication with the evaporator module and the condenser module for circulating refrigeration through the evaporator module and the condenser module. The box-like structure is selectively insertable in to and out of the equipment compartment.

The evaporator module may include a housing, an evaporator coil disposed within the housing, and an evaporator fan/motor assembly operatively associated with the evaporator coil and mounted to the housing. The condenser module may include a condenser coil and a condenser fan/motor assembly operatively associated with the condenser coil.

A liner may be disposed within the first section of the interior space of the refrigeration cassette, the liner including a bowl-like depression adapted to receive the evaporator module. The liner may have contoured surfaces to reduce airflow losses and may be made of plastic or other material having a relatively high chemical resistance.

BRIEF DESCRIPTION OF THE DRAWINGS

For a further understanding of these and objects of the invention, reference will be made to the following detailed description of the invention which is to be read in connection with the accompanying drawing, where:

FIG. 1 is a sectioned side elevation view of a refrigerated merchandiser equipped with a modular refrigeration cassette;

FIG. 2 is a sectional side elevation view taken along line 2-2 of FIG. 1;

FIG. 3 is a perspective view of an embodiment of a modular refrigeration cassette in accordance with the invention;

FIG. 4 is a sectioned side elevation view of the modular refrigeration cassette depicted in FIG. 3;

FIG. 5 is a plan view taken along section 5-5 of FIG. 4; and

FIG. 6 is a perspective view illustrating an embodiment of a liner for the modular refrigeration cassette depicted in FIG. 3.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 and 2 in particular, there is depicted a refrigerated cold beverage merchandiser, designated generally by the reference numeral 10, including an interior product display space 100 for holding product 110 to be purchased, such as for example bottled or canned soda, milk, water, juices, fruit drinks, beer and other beverages. Although the invention will be described herein with reference to the depicted embodiment of a refrigerated cold beverage merchandiser, it is to be understood that that invention may be applied to other refrigerated display merchandisers for displaying perishable and frozen comestibles and beverages, including for example meats, poultry, fish, diary products, prepackaged frozen foods, and other products that need to be maintained in a controlled environment.

The beverage merchandiser 10 includes a cabinet 20 housing a refrigerated interior product display space 100 and a separate equipment compartment 55 disposed separate from, and may be heat transfer insulated from, the refrigerated interior product display space 100. The cabinet 20 has a top wall 22 and a surrounding side wall structure including a rear wall 34, a front wall 32, and opposed generally vertically extending side walls 36 and 38. The cabinet also includes a lower wall 24 disposed between the refrigerated interior product display space 100 located thereabove and the equipment compartment 55 located there beneath. The interior product display space 100 may be accessed from exteriorly of the cabinet 20 through an access opening, which in the depicted embodiment is an open area at the front of the cabinet. This open area may be open to the environment or may be covered, as in the depicted embodiment, by at least one door 40 mounted to the cabinet 20. The door 40 extends across the open area and has a transparent viewing area, for example a glass panel, through which at least a portion of the interior product display space 100 can be viewed. The door 40 is selectively positionable between a closed position covering the open area and an open position in which consumers may access the interior product display space 100 to remove a product for purchase. Although the embodiment of the display merchandiser 10 depicted in the drawing has only one door 40, it is to be understood that the display merchandiser may have one, two, three or more doors that collectively cover the open area when in the closed position. The door or doors 40 may be mounted to the cabinet 20 in a conventional manner, for example on hinges for pivotal movement or on a track for sliding movement between an open and closed position.

In the depicted embodiment, the top wall 22, the lower wall 24, rear wall 34 and the side walls 36 and 38 are heat transfer insulated for insulating the refrigerated interior product display space 100, from the environment exterior of the interior product display space 100. A plurality of shelves 112 are disposed within the interior product display space 100. The shelves 112 are adapted as appropriate to support the particular product being displayed for purchase. The specific number, arrangement and configuration of the shelves 112 is not germane to the invention and is within the skill of one of ordinary skill in the art to select for the particular product being displayed.

A rear panel 134 is provided spaced inwardly of the rear side wall 34 to establish, in part, a refrigerated air supply duct 104 between the rear side wall 34 and a rear panel 134. The interior product display space 100 within the refrigerated interior of the display cabinet 20 is bounded by the top wall 22, the lower wall 24, the side walls 36, 38, and in part by each of the rear wall 34 and the rear panel 134. In the depicted embodiment, refrigerated air enters into the product display space 100 to cool product displayed therein in part through an air outlet 109 at the upper end of the air supply duct 104 and in part through a plurality of openings 135 provided in the rear panel 134. Refrigerated air exits the product display space 100 through an opening 102 provided in the lower wall 24.

The equipment compartment 55 is located within the cabinet 20 beneath the lower wall 24 and is separated by the lower wall 24 from the refrigerated interior product display space 100 of the cabinet 20. The lower wall 24 forms a common wall separating the refrigerated interior space and the equipment compartment. The lower wall has a top surface that forms the floor or deck of the interior product display space and has an under surface that faces the refrigeration unit cassette 50 of the refrigeration unit 15 housed within the equipment compartment. The refrigeration unit 15 includes an evaporator module 160, including an evaporator coil 60 disposed within a housing 61 and at least one associated evaporator fan/motor assembly 62, a condenser module 170 including a condenser coil 70 and at least one associated condenser fan/motor assembly 72, and a compressor 74. The evaporator coil 60 and its associated evaporator fan/motor assembly 62 are housed within a first section 53 of the refrigeration unit cassette 50 which is separated by division wall 68 from a second section 57 of the refrigeration unit cassette 50 wherein the condenser 70, its associated condenser fan/motor assembly 72 and the compressor 74 are housed. The first section 53 of the refrigeration unit cassette 50 is sized to accommodate a range of evaporator modules 160 having different capacities and the second section 57 of the refrigeration unit cassette 50 is sized to accommodate a range of condenser modules 170 of different capacities, thereby ensuring that a given cassette design may be used over a relatively wide range of refrigeration capacities.

Referring now also to FIGS. 3, 4 and 5, the refrigeration cassette 50 comprises a generally rectangular box-like structure defining an interior space having a top flange 52, a base plate 54, and a surrounding wall structure 56 extending generally vertically between the top flange 52 and the base plate 54 formed of a front plate 56A, a back plate 56B, and opposed side plates 56C. The division wall 68 extends between the opposed side plates 56C from an upper, forward region of the cassette 50 to the back plate 56B to separate the interior of the refrigeration unit cassette 50 into the aforementioned first section 53 and second section 57. The condenser coil 70, its associated condenser fan/motor assembly 72, and the compressor 74 are mounted to the base plate 54 which forms the floor of the cassette refrigeration unit 50. The condenser coil 70 and its associated condenser fan/motor assembly may be mounted to a common support plate, which is adapted to be mounted to the base plate 54, thereby forming the condenser module 170. The base plate 54 is slidably mounted within the compartment 55 to facilitate disposition of the cassette 50 into and out of the compartment 55 in order to facilitate servicing of the refrigeration equipment therein, including removal and replacement of the evaporator module 160 and the condenser module 170 as distinct units. A condensate tray 76 may be provided to collect condensate dripping from the evaporator coil 60. The condensate tray 76 serves as a condensate evaporation tray wherein condensate collecting therein is evaporated by hot air exhausted from the condenser as the hot air passes over the condensate tray 76.

The evaporator coil 60, the condenser coil 70 and the compressor 74 are coupled in a closed-loop refrigerant circulation circuit (not shown) in a conventional manner for refrigerating air from the interior product display space 100. The condenser fan/motor assembly 72, typically a single fan and motor, is operative, typically only when the compressor 74 is in operation, to draw air from outside the refrigerated merchandiser 10, such as for example from the ambient environment external thereof through the front grille 12 provided in the lower front wall 32 of the cabinet 20, through an opening 59 provided in the front plate 56A of the cassette 50 and over the condenser coil 70. As the external air passes over the condenser coil 70 in heat exchange relationship with the refrigerant being passed therethrough by the compressor 74, the refrigerant is cooled and the air heated. Having traversed the condenser coil 70, the hot air is exhausted out of the compartment 55 to return to the external environment through exhaust channel 77 formed beneath the first section 53 in the aft portion of the second section 57 of the cassette 50. A portion of the air drawn through the cassette 50 by the condenser fan passes over the compressor 74 to assist in cooling the compressor.

The cooled refrigerant is circulated from the condenser coil 70 through the closed-loop refrigerant circulation circuit (not shown) to the evaporator coil 60. The evaporator fan/motor assembly 62, which may be a single fan and motor or a plurality of fans with associated motors, is operative to draw air into the first section 53 of the refrigeration unit 50, also referred to as the evaporator compartment, from the interior product display space 100 through the air return inlet opening 102 in the lower wall 24 and thence pass the air over the evaporator coil 60 to and through the refrigerated air supply duct 104 to return to the product display space 100. As the circulating air passes over the evaporator coil 60, the air is cooled as it passes in heat exchange relationship with the chilled refrigerant circulated through the evaporator coil 60 by the compressor 74 and the refrigerant is heated and evaporated. The evaporator fan 62 circulates refrigerated air having traversed the evaporator coil 60 from the evaporator compartment 53 back into the refrigerated interior product display space 100 through a return air outlet 108 located in the lower wall 24 aft of rear panel 134 and into refrigerated air supply duct 104.

A cover plate 120 may be disposed over the return air inlet 102 in spaced relationship with and superadjacent the base wall 24 thereby forming flow passage between the cover plate 120 and the base wall 24 through which refrigerated air returning from the product display space 100 flows into the air return inlet 102. The cover plate 120 covers the air return inlet 102, thereby causing the downwardly directed refrigerated air to flow outwardly toward the surrounding walls of the cabinet as the refrigerated air approaches the lower region of the product display space 100 in order to pass beneath the cover plate 120 into the air return inlet 102 in the lower wall 24. In doing so, the refrigerated air passes through the product on the lower shelves to more evenly cool that product and to block the refrigerated air from funneling downwardly directly into the return air return inlet 102. The cover plate 120 also restricts the flow of spills or leaks from product in the product display space 100 from flowing directly into the evaporator compartment 53 and fouling the evaporator and/or evaporator fan assembly.

In one embodiment, the cover plate 120 includes a peripheral flange 126 extending generally vertically therefrom to the base wall 24 for supporting the cover plate 120 over the air return inlet 102 in the base wall 24. A plurality of circumferentially spaced openings 125 are provided in the circumferential flange 126 to form the air flow passage connecting the refrigerated interior space 100 in flow communication with the air return inlet 102 to the evaporator compartment 53 of the refrigeration unit cassette 50.

The division plate 68 has a forward portion 68A and an aft portion 68B. The aft portion 68B of the division plate 68 extends generally horizontally beneath the evaporator assembly in spaced relationship with and above the base plate 54 to form a channel 77 in the aft portion of the condenser compartment 57. The channel 77 constitutes an exhaust channel through which hot air exiting the condenser coil 70 passes out of the equipment compartment 55 to the environment external of the refrigerated merchandiser 10 through an opening at the back of the cabinet 20. The condenser coil 70, its associated condenser fan/motor assembly 72, and the compressor 74 are mounted to the forward portion of the base plate 54. The forward portion 68A of the division plate 68 slopes downwardly from an upper, forward region of the condenser compartment 57 to the meet the aft portion 68B of the division plate 68. In doing so, a converging channel 73 is defined between the base plate 54 and the forward portion 68A of the division plate extending form the outlet of the condenser 70 to open to the exhaust channel 77. The converging channel 73 in effect defines a nozzle for accelerating the condenser exhaust airflow passing therethrough to a relative higher velocity, that is a velocity substantially higher than the velocity of the condenser exhaust airflow exiting the condenser module 170. The forward section 68A of the division plate 68 is depicted as having two sections of different slope. It is to be understood, however, that the forward section 68A of the division plate 68 may have a constant slope or even a curvilinear slope, as desired.

The condensate dripping from the evaporator coil 60, which is disposed in the aft portion of the evaporator compartment 53, drains therefrom through a drain tube 89 passing through the division wall 68 into the condensate tray 76 disposed in the exhaust channel 77 beneath the evaporator compartment 53 to collect condensate dripping from the evaporator 60. The condensate tray 76 may be integrally formed in the base plate 54. For example, the condensate tray 76 may be defined by a raised brim 78 stamped in the base plate 54 as illustrated in FIGS. 4 and 5. Alternatively, the condensate tray 76 could be a separate structure secured to the base plate 54. For example, the condensate tray 76 may be defined by a raised brim 78 stamped or otherwise formed in the base plate 54 as illustrated in FIGS. 4 and 5. Alternatively, the condensate tray 76 could be a separate insert secured to the base plate 54. In such case, the condensate tray could be formed of a different material than the base plate, such as a non-metallic material, for example ABS plastic, or stamped or otherwise formed from aluminum or other metallic material.

The condenser fan 72 draws ambient air through the condenser coil 70 to absorb heat from the refrigerant passing through the condenser coil as in conventional practice to condense the refrigerant. The hot air exiting the condenser 70 accelerates in velocity as it passes through the converging channel 73 and into the exhaust channel 77. The high velocity, hot air passing through the exhaust channel 77 passes over the surface of the condensate collected in the condensate tray 76. The high velocity characteristic of the hot air passing through the exhaust channel 77 enhances the evaporation of condensate collected in the condensate tray 76 as the rate of evaporation of the condensate is increased due to increased air to condensate contact.

Referring now to FIGS. 3, 4 and 6 in particular, a plastic liner 80 may be inserted within the evaporator compartment 53 to protect the surfaces of the metal plates forming the structure of the refrigeration unit cassette 50 from chemical attack by liquids that might spill or flow into the cassette from the product display region 100. The plastic liner 80 constitutes a formed body having a flange 82 extending circumferentially thereabout, a downwardly slopping floor 84 at its forward end and bowl-like depression 86 at its aft end. The plastic liner 80 is formed to fit within the compartment 53 superadjacent the division wall 68 with the flange 82 supported on the top flange 52 of the cassette 50. The bowl-like depression 86 is adapted to receive the evaporator module 160, which constitutes the evaporator 60, its housing 64, and one or more evaporator fan/motor assemblies 62 mounted to the evaporator housing 64, each by means of a support bracket 66. The evaporator module 160 is releaseably secured, for example by bolts or screws, to the sides of liner 80 and or the side walls 56C of the refrigeration unit cassette 50. The bowl-like depression 86 are sized to accommodate a range of evaporator modules of different capacity, thereby enabling a given refrigeration cassette to be used over a wide range of refrigeration capacities. It is to be understood that the liner 80 may be formed from a non-plastic, formable material being more chemically resistant than the metal walls of the refrigeration cassette 50 and sufficient strength to support the evaporator module, such as for example fiberglass.

The plastic liner 80 is contoured to have generous radii in order to minimize airflow losses as the refrigerated air passes from the product display region 100 through the evaporator 60 and into the refrigerated air supply duct 104. Additionally, a trough 88 may be formed in the slopping floor 84 of the liner 80 to collect and direct any liquid that may spill or flow into the refrigeration unit cassette 50.

A sealing system is provided including a sealing member 58 positioned between the lower wall 24 and the refrigeration cassette 50 and a positioning apparatus 150 for placing the refrigeration unit cassette 50 into sealing relationship with the common wall, which in the depicted embodiment is the lower wall 24 that separates the refrigerated interior product display space 100 from the equipment compartment 55. The sealing system prevents refrigerated air returning to the refrigeration unit 15 from the product display space 100 from bypassing the evaporator 60 and instead flowing directly into the inlet 108 to the air supply duct 104 from the air return inlet 102. The sealing system also prevents ambient air from externally of the refrigeration unit cassette 50, such as the ambient air that has been drawn through the front grille 12 to pass through the condenser 70, from being drawn into the refrigerated air returning to the refrigeration unit 15 through the air return inlet 102 in the lower wall 24.

The sealing member 58 may be mounted to the under surface of the lower wall 24 about the opening 102 in the lower wall 24, or may be mounted or simply carried upon to the upper surface of the top flange 52 of the refrigeration unit cassette 50. The sealing member 58 extends at least about the opening 51A to the refrigeration cassette 50, as illustrated in FIG. 3, which is substantially commensurate with and is in flow communication with the opening 102 in the lower wall 24. The sealing member 58 also may extend about the opening 51B provided rearward of the opening 51A, as illustrated in FIG. 3, which opens in flow communication with opening 108 in the lower wall 24. In the depicted embodiment the sealing member 58 takes the form of a rectangular frame extending along the top flange 52 with a cross member 58A extending along the top of the housing 64 of the evaporator module 60.

The sealing member 58 may comprise one or more compressible seals provided on the refrigeration unit cassette 50 which are compressed against the lower wall 24 when the cassette refrigeration unit 50 is raised within the compartment 55 by operation of the positioning apparatus 150. However, the sealing member 58 may also comprise one or more non-compressible seals, such as contact seals, that coact with the respective opposing surfaces of the refrigeration unit cassette and of the common wall separating the refrigerated interior space from the equipment compartment and surrounding the respective openings therein to provide the desired sealing arrangement therebetween when the cassette refrigeration unit 50 is positioned by operation of the lifting apparatus 150 to sandwich the sealing member 58 therebetween.

The refrigeration cassette of the present invention has been described herein with reference to the exemplary embodiments depicted in the drawings for purposes of illustration and to facilitate understanding of the invention. Those skilled in the art will realize that modifications, some of which may have been alluded to hereinbefore, may be made to the depicted embodiments without departing from the spirit and scope of the present invention.