WO2008063184A1

WO2008063184A1 - Refrigerated case

Info

Publication number: WO2008063184A1
Application number: PCT/US2006/049364
Authority: WO
Inventors: Eugene D. Daddis, Jr.; Mary D. Saroka; Brian J. Mead
Original assignee: Carrier Corporation
Priority date: 2006-11-20
Filing date: 2006-12-27
Publication date: 2008-05-29

Abstract

A refrigerated case (20; 220) has a body (22) having a refrigerated compartment (24). A base (40) is below the refrigerated compartment. A refrigeration module (50) is within the base. A first air flowpath (512) recirculates between the refrigerated compartment and the heat absorption heat exchanger (66). A second air flowpath extends through the heat rejection heat exchanger (62). Baffles (e.g., first and second lateral baffles (120, 122; 228, 229) and/or a lower baffle (160)) are positioned within the base to at least partially block a recirculation of air along the second air flowpath.

Description

REFRIGERATED CASE

CROSS-REFERENCE TO RELATED APPLICATION

[0001] Benefit is claimed of U.S. Patent Application Ser. No. 60/866,575, filed November 20, 2006, and entitled "Refrigerated Case", the disclosure of which is incorporated by reference herein as if set forth at length.

BACKGROUND OF THE DWENTION

[0002] The invention relates to refrigerated cases. More particularly, the invention relates to such cases having refrigeration modules. [0003] In several configurations of refrigerated case (including freezers), the refrigeration equipment is located in a self-contained module which may be installed to and removed from the case as a unit. An exemplary module includes the compressor, condenser, expansion device, evaporator, and associated fans. The module is typically installed in a base of the case below the refrigerated compartment. The module is typically installed to the base via rearward insertion through a front of the base. The insertion may be followed by a short lifting of the module to mate portions of the module forming the recirculating air flowpath with mating portions of the remaining structure of the case (e.g., and compressing a gasket/seal therebetween).

SUMMARY OF THE INVENTION [0004] Accordingly, one aspect of the invention involves a refrigerated case having a refrigerated compartment. A base is below the refrigerated compartment. A refrigeration module is within the base. A first air flowpath recirculates between the refrigerated compartment and the heat absorption heat exchanger. A second air flowpath extends through the heat rejection heat exchanger. Baffles (e.g., first and second lateral baffles and/or a lower baffle) are positioned within the base to at least partially block a lateral recirculation of air along the second air flowpath.

[0005] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is a partially exploded view of a refrigerated case.

[0007] FIG. 2 is a longitudinal (front-to-back) vertical sectional view of the case of FIG. 1.

[0008] FIG. 3 is a front view of the case of FIG. 1 with door and grille removed. [0009] FIG.4 is an enlarged view of a platform area of the case of FIG. 2.

[0010] FIG. 5 is a vertical schematic view of a lateral warm air recirculation.

[0011] FIG. 6 is a lateral schematic view of an under-module warm air recirculation.

[0012] FIG. 7 is a downward sectional view of the case of FIG. 1 with grille removed. [0013] FIG. 8 is an enlarged view of a lateral space aside the module of FIG. 3.

[0014] FIG. 9 is a view of a pair of lateral baffles.

[0015] FIG. 10 is a view of a lower baffle.

[0016] FIG. 11 is a proximal downward sectional view of an alternate case base.

[0017] FIG. 12 is a view of baffles of the alternate case base. [0018] Like reference numbers and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

[0019] FIG. 1 shows a refrigerated case 20 having a housing (body) 22 surrounding a refrigerated interior compartment 24. The exemplary housing 22 includes a main body 25 a door 26 positioned to close and open across a front opening 28 of the main body. The exemplary body 22 has a left sidewall 30, a right sidewall 32, a back 34, and a top 36. For non-limiting reference, left and right are viewed from the perspective of the case rather than a user facing the case. A lower portion of the body 22 forms a base 40 including an exemplary platform 42. A base compartment or bay 44 is separated from the compartment 24 by a compartment bottom wall (dividing wall) 46. A front of the compartment 44 may be closed by a removable grille 48. An overall case depth D is shown in FIG. 2. An overall case body height Hi, an overall case height H₂, and an overall case width W are shown in FIG. 3. [0020] In the exemplary case 22, a recirculating airflow is directed from/to the compartment 24 by a refrigeration equipment module 50 (e.g., containing the compressor, heat exchangers, expansion device, fans, and the like). The module 50 (discussed in further detail below) has an installed position within the compartment 44. The module 50 is removable from the compartment 44 as a unit (e.g., after removing the grille 48, if present), advantageously without the use of tools or with only slight tool use. The exemplary module 50 has a front 51, a back 52, a top 53, a bottom 54, a left side 55, and a right side 56. [0021] FIG. 2 shows further details of the exemplary case 20 and module 50. The exemplary module 50 contains the compressor 60, the heat rejection heat exchanger (e.g., condenser and/or gas cooler) 62, the expansion device 64, and the heat absorption heat exchanger (evaporator) 66 sequentially along a recirculating refrigerant flowpath (e.g., further defined by appropriate refrigerant lines/conduits). A recirculating airflow 510 passes along a recirculating flowpath (the cold air flowpath) 512 through the module 50 and compartment 24 to cool the compartment. The exemplary flow 510 passes from the compartment 24 into the module 50 through a first port 70 in the wall 46 and returns to the compartment 24 via a second port 72 in the wall 46. The exemplary flow 510 is driven by an electric fan 74 in the flowpath 512 in the module 50. [0022] An airflow 514 passes along a flowpath (the warm air flowpath) 516 which extends through the heat rejection heat exchanger 62. Subject to considerations discussed further below, the exemplary path 516 is an open path entering through the grille 48, then entering the front 51 of the module 50 and passing through the heat rejection heat exchanger 62 before exiting the rear 52 of the module and rear of the case. An electric fan 76 may be in the warm air flowpath 516 in the module 50 to drive the airflow 514. A wall 80 may separate the flowpaths 512 and 516 within the module. As so far described, the case may be representative of a portion of the possible cases to which the present disclosure may be applied (e.g., to reengineer or further engineer a baseline case configuration). [0023] The exemplary platform 42 (FIG. 1) includes a transverse front base rail 90 and a transverse rear base rail 92. Left and right longitudinal rails 93 and 94 join the base rails. The exemplary base rails have downwardly-open C cross-sections for strength. The exemplary rails 93 and 94 have L-shaped cross-sections with one web or flange resting on the upper surfaces of the base rails and the other extending upward from a laterally inboard junction. An exemplary four support feet 95 (FIG. 2) are mounted to the base rails adjacent the left and right ends of the base rails to support the case atop a floor or ground surface 96. The feet may be adjustable for leveling. For lifting the module into the installed position, the exemplary platform supports a pair of lifting arms 99 and 100 (FIG. 3). Each lifting arm includes a forward lever portion 101, a fulcrum portion 102 (FIG. 4), and a pair of driven portions 103 which may engage the underside 54 of the module to raise the module to the installed position and lower it from the installed position.

[0024] An exemplary baseline case configuration may be subject to an undesirable level of recirculation along the warm air flowpath 516. This recirculation involves air discharged from the condenser returning to the condenser without having cooled to ambient temperature. With warmer-than-ambient air entering the condenser, heat rejection and system efficiency are reduced. A significant portion of this undesirable recirculation may occur within the footprint of the case. For example, a first component of the recirculation may be lateral. The lateral recirculation 520 (FIG. 5) may be along flowpath portions 522 between associated sides 55 and 56 of the refrigeration module (or ducting within the module surrounding the warm air flowpath) and the adjacent sides of the refrigerator footprint (e.g., between the module side and the inboard surface of a base sidewall or base sidewall portion of a case sidewall, if any).

[0025] Another component of the recirculation may be an under-module recirculation flow 524 (FIG. 6). For example, this may involve flow passing along a flowpath portion 526 between the module underside 54 and the building floor or a bottom panel of the base. An exemplary under-module recirculation 524 may pass downward upon exiting the rear 52 of the module through an opening between the module and a transverse rear base rail of the platform at the bottom of the base or below the base rail. The recirculation passes between the module underside and the floor and returns upward through a gap between the lower front edge of the module and a front base rail (e.g., to which support feet, wheels, casters, rollers, or other supports are mounted). Accordingly, it may be desirable to at least partially block the flowpath portions 522 and 526 to reduce the recirculating flow rate and, thereby, reduce the air temperature entering the heat rejection heat exchanger.

[0026] FIG. 7 shows side (lateral) baffles 120 and 122 positioned to block the flowpaths 522. The exemplary baffle 120 is positioned in a space 124 between the left side 55 of the module 50 and the interior surface 126 of the left sidewall. Similarly, the baffle 122 is positioned in a space 128 between the right side 56 of the module 50 and the interior surface 130 of the right sidewall. [0027] FIGS. 7 and 8 show exemplary positioning of the baffles 120 and 122. Each exemplary baffle 120, 122 is formed as an L-sectioned piece of bent sheetmetal. The foot of the L forms a mounting flange 140 which may be mounted (e.g., via screws or other fasteners) to the adjacent sidewall surface. The leg 142 of the L is oriented vertically and extends transversely toward an edge 144 near the adjacent side 54 or 55 (FIG. 8) of the module. The exemplary baffles 120 and 122 block a majority of a cross-section of the associated space 124, 128. For example, they may block at least 75% or at least 90% of this area and the associated recirculation (mass flow of air). The baffles may have an array of perforations 150 (FIG. 8) or other apertures so as to create a flexible inboard portion to accommodate assembly tolerances in module position, and the like. The baffles may have notches (e.g., a relieved corner as shown) or other features to accommodate wiring to the module. The baffles may have heights so as to substantially fill the base compartment (e.g., at least 90% of the base compartment height and a height greater than the module height). Exemplary heights are 25-45cm, more narrowly 30-40cm. Exemplary widths are 4-50cm, or more due to larger variation in common unit widths. [0028] To similarly block the under-module recirculation flow 524, FIGS. 1 and 4 show a lower baffle 160. The exemplary baffle 160 is mounted below the rails 93 and 94 immediately behind the rail 90. The exemplary baffle 160 is formed as a downwardly-open C-sectioned sheetmetal channel. The baffle 160 functions to reduce an opening for the under-module recirculation from an initial size Si to a smaller restricted size S₂. In the illustrated example, the associated flow reduction is less than the associated reduction of the lateral baffles. Other reductions are possible. For example, a portion of the exemplary gap S₂ is associated with the raising and lowering of the module. This gap might effectively be eliminated via a flexible baffle that engaged the module underside during such movement. Nevertheless, and especially when combined with the lateral baffles, overall recirculation reduction may be significant (e.g., an overall reduction of in excess of 50% of a baseline recirculation through the footprint of the case). In the example, all three of the baffles are at similar front-to-back position so as to advantageously cooperate with each other. [0029] The exemplary case 20 features an overall width not much greater than its module width. Accordingly, the lateral baffles 120 and 122 are relatively small. FIG. 11 shows a relatively wider case 220 with relatively wide lateral spaces/gaps 222 and 224 aside a similar module associated with similarly positioned longitudinal rails 93 and 94 but a wider base rail 226 extending laterally farther beyond the rails 93 and 94. The exemplary case 220 includes a similar lower baffle 160. However, the excess width of the spaces/gaps create downwardly-open gaps aside the rails 93 and 94. Accordingly, each of the baffles 228 and 229 has a base portion 230 in addition to the foot and leg portions 232 and 234 of the L-section to close those gaps.

[0030] One or more embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, the principles may be applied in the retrofit of an existing case or the reengineering of an existing case configuration. In an exemplary retrofit or reengineering situation, details of the baseline may influence details of any particular implementation. Accordingly, other embodiments are within the scope of the following claims.

Claims

CLAIMS What is claimed is:

1. A refrigerated case (20; 220) comprising: a refrigerated compartment (24); a base (40) at least partially below the refrigerated compartment; a refrigeration module (50) within the base and including: a compressor (60); a heat rejection heat exchanger (62); an expansion device (64); and a heat absorption heat exchanger (66); a first air flowpath (512) recirculating between the refrigerated compartment and the heat absorption heat exchanger; a second air flowpath (516) extending through the heat rejection heat exchanger; and first and second lateral baffles (120, 122; 228, 229) positioned within the base to at least partially block a lateral recirculation (520) of air along the second air flowpath.

2. The case of claim 1 further comprising: a lower baffle (160) positioned to at least partially block an under-module recirculation (524) of air along the second flowpath.

3. The case of claim 2 wherein: the first and second lateral baffles and the lower baffle are, combined, effective to block at least 50% of said recirculation within the footprint of the case.

4. The case of claim 2 wherein: the first and second lateral baffles have heights greater than a height of the module; and the lower baffle has a width greater than a width of the module.

5. The case of claim 4 wherein: the first and second lateral baffles have widths of at least 75% of widths of associated spaces between the module and adjacent sidewalk of the base; and the lower baffle has a depth of at least three inches.

6. The case of claim 2 wherein: the lower baffle is mounted immediately behind a front base rail (90).

7. The case of claim 1 wherein: the first and second baffles are effective to block at least 50% of said lateral recirculation.

8. The case of claim 1 wherein: the first and second baffles are effective to block at least 75% of said lateral recirculation.

9. The case of claim 1 wherein: the module further includes a first fan (74) along the first air fiowpath and a second fan (76) along the second air fiowpath.

10. The case of claim 1 wherein the module is formed as a generally right parallelepiped.

11. The case of claim 1 wherein the module is removable from the case as a unit.

12. A method for retrofitting a refrigerated case (20; 220) or reengineering a configuration of the case comprising: adding left and right side baffles (120, 122; 228, 229) aside a module-receiving space to at least partially block internal recirculation of a warm airflow (514) through the module (50).

13. A method comprising: initially operating a refrigerated case (20; 220) having a refrigeration module (50) by: driving a first airflow (510) along a recirculating fiowpath (512) through a refrigerated compartment (24) of the refrigerated case and the refrigeration module; driving a second airflow (514) through the refrigeration module to remove heat from the refrigerant, a portion (520; 524) of the second airflow passing around the module within a footprint of the case to recirculate; adding at least one blocking member (120; 122; 160; 228; 229) positioned to at least partially block said recirculating portion; and after the adding, operating the refrigerated case with reduced recirculation of the second airflow.

14. The method of claim 13 further comprising: removing the refrigeration module as a unit; and reinstalling the refrigeration module or installing a replacement refrigeration module.

15. The method of claim 13 wherein: the installing of the at least one blocking member comprises: installing left and right side blocking members (120, 122; 228, 229); and installing a lower blocking member (160).

16. The method of claim 13 wherein: the operating after the adding is at otherwise similar conditions but greater thermal efficiency than the operating before the adding.

17. The method of claim 13 wherein: the adding is effective to block at least 50% of recirculation within the footprint of the case.

18. The method of claim 13 wherein: the adding is effective to block at least 75% of recirculation within the footprint of the case.