Information
-
Patent Grant
-
6240739
-
Patent Number
6,240,739
-
Date Filed
Thursday, August 17, 200024 years ago
-
Date Issued
Tuesday, June 5, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Tapolcai; William E.
- Ali; Mohammad M
Agents
- Michael Best & Friedrich, LLP
-
CPC
-
US Classifications
Field of Search
US
- 062 255
- 062 246
- 062 256
- 312 116
- 454 193
-
International Classifications
-
Abstract
A cover for a cooling unit, such as an evaporator assembly, of a display refrigerator. The cover is advantageously made of a single piece of material, preferably an injection molded, filled polypropylene plastic, which is capable of withstanding the harsh conditions found in a display refrigerator. The cover is further advantageously configured to enhance the operation of the evaporator assembly, protect the evaporator assembly, insulate the frozen or refrigerated food and drink items from the heat generated by the evaporator assembly, and decrease the time needed to install the cover into or remove the cover from the display refrigerator.
Description
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates to display refrigerators, and more particularly to display refrigerators having an internal evaporator assembly.
2. Related Prior Art
Display refrigerators are commonly used in retail outlets such as supermarkets, restaurants, convenience stores and other establishments that sell frozen or refrigerated items. Display refrigerators typically include a case having a plurality of shelves supporting the items on display. Doors, usually made of glass, allow a consumer to survey the selection of items without having to open one or more of the doors. When a selection is made, the consumer opens the appropriate door, removes the desired item and thereafter closes the door.
It is known to provide a display refrigerator with an evaporator assembly to keep the interior display space of the refrigerator cold. The evaporator assembly is generally housed beneath the interior display space. It is also known to provide the display refrigerator with a fan that is operable to circulate air contained by the display case through the evaporator assembly. In general, the fan draws air from the interior display space through the evaporator assembly where the air is cooled, and then recirculates the air into the interior display space. In this regard, display refrigerators periodically operate to defrost the refrigerant coils that are part of the evaporator assembly. A consequence of such defrost cycles is that periodically the evaporator warms the air in the lower region of the display case adjacent the evaporator coils.
It is also generally known to separate the evaporator assembly with a grill or cover to conceal the evaporator assembly and to protect the components of the evaporator assembly from damage by items falling from the shelving or by spillage. Known covers are often made of multiple pieces which are configured to cooperate in forming an evaporator cover assembly and which extend between the front of the display case and the back of the display case. The individual pieces of the cover assembly are generally made of metal grills and/or sheets to provide strength and to withstand low temperatures, though it is also known to provide a multiple piece cover assembly made of plastic or a combination of metal and plastic. The individual pieces are also configured to expand and contract when exposed to varying temperature conditions in the display refrigerator caused by the alternating operation of the evaporator assembly through cooling and defrost cycles.
SUMMARY OF THE INVENTION
As can be appreciated, a cover used to conceal an evaporator assembly placed beneath an interior display space must be of sufficient strength to substantially span the distance between the front of a display case to the back of a display case or to the front of the evaporator coil. The cover must also be able to withstand the low operating temperatures of a display refrigerator without cracking. Moreover, during defrost cycles the air in the interior display space above the cover is generally colder than the air directly surrounding the evaporator assembly and below the cover. Thus, the cover must also be able to withstand a temperature differential between its top side and its bottom side without cracking.
A problem with metal grills and covers is that manufacturing costs for metal display refrigerator evaporator covers are not viewed as cost effective. Furthermore, metal is generally a poor insulator. As a consequence, the warmth generated by the evaporator assembly or other heat source during defrost cycles is permitted by metal covers to infiltrate the upper regions of the display refrigerator. This heat infiltration is undesirable primarily because of the prospective damage to goods in the display refrigerator. Another substantial disadvantage caused by heat transfer through known cover assemblies is the fact that the defrost cycles must continue for a longer period than optimum, and subsequent cooling cycles must cool not only air warmed in the lower regions of the display refrigerator, but also the air in the upper display. Another problem with grills in general is that particulates, such as dust, dirt and the like, can fall through the grill into the evaporator assembly and, consequently, adversely affect the operation of the evaporator assembly. In addition, grills often expose pipes, wiring, conduits and other utilities serving the evaporator assembly, as well as dirt, dust and other articles that may fall into the lower portion of the display refrigerator. Such exposure is generally unsightly and undesirable in a retail setting.
Known plastic evaporator assembly covers present deficiencies in the areas of strength and durability. In general, known plastic cover assemblies are not sufficiently strong to span the distances necessary to cover an evaporator assembly. Also, known plastic covers tend to crack at low temperature.
One problem with known multiple piece cover assemblies concerns the amount of time needed to install the pieces into or remove the pieces from a display refrigerator. Multiple piece evaporator assembly covers made of a metal portion and a plastic portion have stress concentrations at the interface of the two different materials because, e.g., of the differences in the expansion and contraction properties of the different materials. These stress concentrations often result in cracking, and generally adversely affect the overall function of the covers and reduce the accepted operating life of the covers.
The invention addresses the problems presented by the prior art. In one aspect, the invention provides a cover that can be positioned between a cooling unit of a display refrigerator and an interior display space of the display refrigerator. The cover is advantageously made of a single piece of material which is adapted to expand from the front of the display case to at least the front of the evaporator coil. Preferably, the single piece cover is made of an injection molded plastic material. The single piece cover is sufficiently strong to span the distance between the front and the back of the display case without sagging or bending. The single piece cover can be exposed to varying temperatures, including very low temperatures, without being damaged or cracked. The single piece cover can also withstand temperature gradients on opposite sides of the cover. Additionally, the single piece cover is a better insulator than metal covers, thereby protecting the items stored in the interior space of the display case from the heat generated by the evaporator assembly during defrost cycles.
In one embodiment, the invention provides a cover positioned between an evaporator assembly and an interior display space of a display refrigerator. The cover includes a main body portion and a grill portion that affords fluid flow, such as air flow, communication between the evaporator assembly and the interior display space, and wherein the main body portion and the grill portion are formed as a single piece of material.
In another embodiment, the invention provides a cover adapted to be housed in a display refrigerator having a display case and an evaporator assembly within the display case. The cover includes an imperforate main body portion overlying the evaporator assembly and a grill portion affording fluid flow communication between the evaporator assembly and the remainder of the display case, wherein the main body portion and the grill portion are formed as a single piece of injection molded plastic material.
In another embodiment, the invention provides a display refrigerator including a display case having a front wall and a rear wall defining an interior space, and an evaporator assembly housed within the interior space. The refrigerator also includes a cover positioned adjacent the evaporator assembly and separating the interior space into a display space and an evaporator assembly portion, the cover extending between the front wall and the rear wall. The cover includes an imperforate main body portion and a grill portion affording fluid flow communication between the display space and the evaporator assembly portion. The grill portion includes a first set of spaced apart, substantially vertical parallel walls and a second set of spaced apart, substantially non-vertical parallel walls which interconnect with said first set of walls to form a plurality of openings. The main body portion and the grill like portion are formed as a single piece of filled polypropylene injection molded plastic. The cover also includes a first side defining a first tab having a recessed upper surface and the cover also includes a second side defining a second tab having a recessed underside and being adapted to be engaged by the first side of a second cover to define therebetween a lap joint.
In another embodiment, the cover further includes a locating stud that is positioned to properly locate the cover within the display refrigerator.
The invention also provides a display refrigerator having a longitudinal length and a cover assembly including multiple covers configured such that portions of adjacent covers are configured to form a lap joint. The covers expand from one side of the display refrigerator to the other. The lap joints provide a simple, yet effective, manner of installing and removing individual covers into and out of a display refrigerator.
In yet another preferred embodiment, the cover includes a notch or recess providing clearance for structural members of the display refrigerator that may support, for example, the display case and/or shelving or to provide clearance for electrical wiring, such as for a lighting system, of the display refrigerator.
Thus the invention provides a unique and advantageous display refrigerator evaporator cover.
The invention also provides a new and improved display refrigerator evaporator cover which is simple to use and relatively inexpensive to make.
The invention provides a display refrigerator cover which conceals the evaporator assembly and other pipes and utilities connected to the evaporator assembly. The cover also prevents dust, dirt and other particulates from passing from the upper regions of the display into the lower portion of the display cabinet housing the evaporator assembly.
Another feature of the invention is a display refrigerator evaporator cover that reduces the overall time needed to install or remove the cover, and that serves as a product stop preventing items from falling into the evaporator assembly.
Still another feature of the invention is a display refrigerator evaporator cover having sufficient strength and made of appropriate material to withstand the environmental conditions of display refrigerators.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a side view, partially in section, of a display refrigerator embodying the present invention.
FIG. 2
is a perspective view of the display refrigerator evaporator cover shown in FIG.
1
.
FIG. 3
is view taken along line III—III in FIG.
1
.
FIG. 4
is a partial cross-sectional view taken along line IV—IV in FIG.
3
.
FIG. 5
is a partial cross-sectional view taken along line V—V in FIG.
3
.
FIG. 6
is a perspective view similar to FIG.
2
and shows the underside of the display refrigerator evaporator cover shown in FIG.
2
.
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1
illustrates a display refrigerator
10
embodying the present invention. The display refrigerator
10
includes a display case
14
having a front wall
18
, a rear wall
22
and top wall
26
defining there between an interior space
30
. The display refrigerator
10
also includes a plurality of shelves
34
mounted on the rear wall
22
and extending into the interior
30
of the display case
14
for displaying food or drink items. The display refrigerator also includes one or more glass doors
38
which are mounted on the front wall
18
and which allow a consumer to survey the interior
30
of the display case
14
before opening the door
38
by way of handle
42
.
The display refrigerator
10
also includes an evaporator assembly
46
which is housed in the lower portion of the display case
14
and which is operable to keep the interior
30
of the display case
14
cold. The evaporator assembly
46
includes cooling coils
50
(shown schematically in
FIG. 1
as a bundle of coils and fins) which extend along the length of the display case
14
. For reasons discussed below, the evaporator assembly also includes (
FIGS. 1 and 4
) a cover mount
54
extending along the lower rear wall
22
into the interior
30
of the display case
14
and having therein one or more location slots or apertures
56
.
The evaporator assembly
46
also includes a fan
58
which is mounted on a plenum
62
located adjacent the lower front wall
18
of the display case
14
. During cooling cycles (as represented by arrows in FIG.
1
), the fan
58
draws air in the interior
30
of the case through the fan plenum
62
and drives the air rearward past the evaporator coils and fins
50
where the air is cooled or, alternatively, heat is removed. In order to defrost the cooling coils and fins
50
of the evaporator assembly
46
, the flow of refrigerant through the evaporator coils is periodically reversed. As is further generally understood, the operation of the evaporator assembly
46
during defrosting cycles generates heat in the region of the coils and fins
50
either through reverse operation of the evaporator assembly or by other means (not shown), such as by electric or hot gas defrost systems.
The display refrigerator
10
also includes an evaporator cover
66
. The cover
66
extends between the front wall
18
and the rear wall
22
of the display case
14
, and overlies the evaporator assembly
46
. The cover
66
conceals the evaporator assembly
46
and protects the components of the evaporator assembly
46
from damage such as if, for example, an item falls from a shelf
34
. The cover
66
also separates the interior space
30
of the display case
14
into an upper, display portion
70
and a lower, housing portion
74
.
Referring to
FIG. 2
, the cover
66
is made of a single piece of plastic and preferably is made by injection-molded or thermo-forming. Although various compositions or types of plastic will work according to the principles of the present invention, a filled polypropylene sold by Ferro Corporation under product code LPP40YR01 is particularly well suited for use in fabricating the cover
66
by injection molding. This, and other suitable plastics, has an R factor superior to that of metal and, therefore, has superior insulative properties compared to metal. Thus, the cover
66
also functions as an insulator between the display space
70
where the cold items are stored and the housing portion
74
wherein the evaporator assembly
46
periodically generates heat, thereby protecting the items housed in the display case
14
from being adversely heated.
The cover
66
is generally rectangular but may be of different shapes depending on the configuration of the display refrigerator
10
. The cover
66
includes (
FIG. 2
) a front edge
86
, a rear edge
90
, and opposite sides
94
and
98
. As best shown in
FIG. 1
, when installed in the display case
14
, the front edge
86
of the cover
66
is adjacent the front wall
18
of the display case
14
and overlies the fan plenum
62
, and the rear edge
90
of the cover
66
is adjacent the rear wall
22
of the display case
14
and overlies the cover mount
54
. As best shown in
FIGS. 1 and 6
, the underside of the cover
66
has a grid or lattice
102
of spaced-apart, generally straight and parallel elongated structural walls or ribs
106
extending between the opposite sides
94
and
98
of the cover
66
and between the front and rear edges
86
and
90
of the cover
66
. The structural ribs
106
vary in height depending on the location of the ribs
106
between the sides
94
,
98
and edges
86
,
90
to accommodate the configurations of the fan plenum
62
, the evaporator assembly
50
and cover mount
54
, while at the same time providing a generally horizontal upper surface. The ribs
102
provide structural strength and stability to the cover
66
to prevent warping and cracking in the cover
66
under loading and thermal stress.
More particularly, the cover
66
(
FIG. 2
) includes a main body portion
110
which is bounded by the rear edge
90
and the opposite sides
94
,
98
and which extends toward the front edge
86
. The main body portion
110
is imperforate and serves an air flow management function by preventing air flow between the display portion
70
of the case
14
and the evaporator housing
74
. The main body portion
110
of the cover
66
provides a planar upper surface
114
and (
FIG. 6
) an underside
118
including the grid
102
of ribs
106
. In the illustrated embodiment, near the rear edge
90
of the cover
66
, the ribs
102
are relatively shallow, and over the fan plenum
62
, the ribs
106
are deeper.
The main body portion
110
also includes (
FIGS. 4 and 6
) a locating member or stud
122
extending from the underside
118
of the cover
66
adjacent the rear edge
90
. The locating member
122
is received by the aperture
56
in the cover mount
54
so that the cover
66
can be properly and easily located within the display case
14
(see also FIG.
1
). It should be noted that the locating stud
122
could be alternatively positioned elsewhere on the cover
66
so as to mate with an appropriately positioned aperture or the like in the display case
14
. Alternatively, the cover
66
could include an aperture or the like similar to aperture
56
, and the display case
14
could include a locating member similar to locating member
122
.
The cover
66
also includes a grill portion
126
adjacent the main body portion
110
and the front edge
86
of the cover
66
. The grill portion
126
also performs air flow management functions by permitting flow of air therethrough. To that end, the grill portion
126
is generally defined by the structural ribs
106
extending from the main body portion
110
toward the front edge
86
and by ribs
106
which extend substantially parallel to the front edge
86
between the sides
94
,
98
. In the grill portion
126
of the cover
66
, the grid
102
of ribs
106
defines a plurality of openings
130
communicating between the top and bottom surfaces
134
,
138
(
FIG. 6
) of the cover
66
, which are respectively defined by the upper and lower extents of the ribs
106
. The top surface
134
of the grill portion
126
adjacent the main body portion
110
extends upwardly from the top surface
114
and has a profile (
FIG. 1
) which curves toward the front wall
18
such that the rearward portion of the grill portion
126
is vertically offset from the forward portion of the main body portion
110
. The grill portion
126
also includes a pair of imperforate sections
142
extending toward the front edge
86
of the cover
66
and respectively along the opposite sides
94
,
98
of the cover
66
.
The top surface
134
of the grill portion
126
ramps downwardly from the rearward extent of the grill toward the front edge
86
. This vertical displacement and ramping of the grill portion
126
discourages the placement of items onto the grill portion
126
, which could adversely affect the overall operation of the evaporator assembly
46
by blocking air flow. In this regard and as best shown in
FIG. 1
, the ribs
106
in the grill portion
126
which extend laterally between the sides
94
,
98
of the cover
66
lie in a plane which is at an acute angle relative to vertical. The laterally extending ribs
106
are so positioned to enhance the proper flow of air from the interior display space
70
through the cover
66
and into the evaporator assembly housing
74
. Also, the angled orientation of the ribs
106
tends to conceal the evaporator assembly
46
from direct observation from outside the front of the display case
14
and prevents the passage of dust, dirt and other particulates into the housing portion
74
for the evaporator assembly
46
. In addition, the angled orientation of the ribs
106
prevents the observation of dust, dirt and other articles that may have fallen into the lower portion of the display refrigerator
10
.
Thus, the cover
66
includes a main body portion
110
and a grill
126
which affords fluid flow communication between the evaporator assembly housing
74
and the interior display space
70
, and provides a cover
66
wherein the main body portion
110
and the grill portion
126
are formed as a single piece of material.
With reference to
FIG. 2
, the cover
66
preferably includes a notch or recess
150
in one of the sides
94
,
98
in order to provide clearance for vertically extending structural members (not shown) that may be provided in the display case
14
and/or shelving
34
. Although not shown, the cover
66
may also include one or more notches like notch
150
elsewhere in the cover
66
depending on the design of the display case
14
. The cover
66
also preferably includes a notch or recess
154
in the front edge so as to provide clearance for an insulated wire bundle or the like (not shown) provided in the display refrigerator
10
for lighting devices or other electrical devices (not shown) which may be mounted in or on the display case
14
. Preferably, the notch
154
is defined by a gap in the front edge
86
and by rib segments
106
. Alternatively, one or more notches like notch
154
could be positioned elsewhere in the cover
66
, depending on the design of the display case
14
. If utilized, the notches
150
and
154
are preferably molded into the single piece cover
66
by installing inserts (not shown) in the injection molding tooling which correspond to the shape and size of the notches. Thus, the cover
66
provides a single piece that extends between the front and rear walls
18
,
22
of the display case
14
.
Those of ordinary skill in the art will readily recognize that a display refrigerator
10
may have a length such that a single cover
66
can be used to separate the display
70
and evaporator housing
74
along the entire length of the display case
14
. However, in the event the display case
14
is elongated, such as is shown in
FIG. 3
, then the invention also provides a cover assembly
170
comprising multiple covers
66
, which extend from one side of the display case
14
to the opposite side. As shown in
FIG. 3
, the sides
94
,
98
of each cover
66
are configured so as to cooperate and form a lap joint
174
with adjoining covers
66
. As best shown in
FIGS. 2 and 5
, the opposite sides
94
,
98
of the cover
66
have respective configurations that mate when overlapped. More particularly, one side
94
of the cover
66
includes a tab portion
178
that extends from the underside
118
of the cover
66
and that defines a recess
182
from the upper surface
114
. Conversely, the opposite side
98
of the cover
66
includes a tab
186
which extends from the top surface
114
and which is configured to overlap the tab
178
and occupy the recess
182
so that the top surfaces
114
of the adjoining covers
66
are flush. The edges
94
,
98
are thus configured and adapted to mate to form the lap joint
174
when assembled.
FIG. 1
also illustrates that the display refrigerator
10
can be provided with a bottom shelf
200
supported by the rear wall
22
in a position overlying the cover
66
or cover assembly
170
. The bottom shelf
200
is configured to extend over the main body portion
110
without covering any part of the grill portion
126
. The shelf
200
includes a vertical edge
202
adjacent the interface of the main body portion
110
and the grill portion
126
, and is intended to discourage items placed on the shelf
200
from sliding onto the grill
126
.
Variations and modifications of the foregoing are within the scope of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.
Various features of the invention are set forth in the following claims.
Claims
- 1. A cover positioned between an evaporator assembly and an interior display space of a display refrigerator, said cover comprising:a main body portion and a grill portion which affords fluid flow communication between the evaporator assembly and the interior display space and wherein said main body portion and said grill portion are formed as a single piece of material.
- 2. A cover according to claim 1, wherein the display refrigerator includes spaced apart front and rear walls and wherein said cover is adapted to extend between the front and rear walls.
- 3. A cover according to claim 1 and further including a locating member for mating connection with a component of the display case so as to properly locate said cover within the display case.
- 4. A cover according to claim 1, wherein one side of said cover is adapted to be overlapped by a portion of an adjoining cover such that a lap joint can be created between the adjoining covers, and wherein an opposite side of said cover is adapted to overlap a portion of yet another adjoining cover such that a lap joint can be created between these adjoining covers.
- 5. A cover according to claim 1, wherein at least one side of said cover includes a notch which extends completely through said cover.
- 6. A cover according to claim 1, wherein said grill portion includes a notch which extends completely through said cover.
- 7. A cover according to claim 1, wherein said grill portion includes a first set of spaced apart, substantially vertical parallel walls and a second set of spaced apart, substantially non-vertical parallel walls which interconnect with said first set of walls to form a substantially grid like portion.
- 8. A cover according to claim 1, wherein said cover includes a top surface which is imperforate along said main body portion and which provides openings in said grill portion.
- 9. A cover according to claim 8, wherein said top surface which at least partially defines said grill portion is downwardly ramped toward an end of said cover.
- 10. A cover adapted to be housed in a display refrigerator having a display case and an evaporator assembly within the display case, said cover comprising:an imperforate main body portion overlying the evaporator assembly and a grill portion affording fluid flow communication between the evaporator assembly and the remainder of the display case, said main body portion and said grill portion being formed as a single piece of injection molded plastic material.
- 11. A cover according to claim 10, wherein the display case includes a front wall and wherein the grill portion is located adjacent the front wall.
- 12. A cover according to claim 10, wherein the display case has a rear wall and wherein the cover includes a locating member located adjacent the rear wall.
- 13. A cover according to claim 10, wherein one side of said cover is adapted to be overlapped by a portion of an adjoining cover such that a lap joint can be created between the adjoining covers, and wherein an opposite side of said cover is adapted to overlap a portion of yet another adjoining cover such that a lap joint can be created between these adjoining covers.
- 14. A cover according to claim 10, wherein at least one side of said cover includes a notch which extends completely through said cover.
- 15. A cover according to claim 10, wherein said grill portion includes a notch which extends completely through said cover.
- 16. A cover according to claim 10, wherein said grill portion includes a first set of spaced apart, substantially vertical parallel walls and a second set of spaced apart, substantially non-vertical parallel walls which interconnect with said first set of walls.
- 17. A cover according to claim 10, wherein said single piece cover is made of a filled polypropylene.
- 18. A cover according to claim 10, wherein said cover includes a top surface which at least partially defines said main body portion and a plurality of ribs underlying the top surface.
- 19. A cover according to claim 18, wherein said top side of the main body portion is generally horizontal.
- 20. A display refrigerator comprising:a display case having a front wall, a rear wall and defining an interior space; an evaporator assembly housed within said interior space; and a cover positioned adjacent said evaporator assembly and separating said interior space into a display space and an evaporator assembly portion, said cover extending between said front wall and said rear wall, said cover including an imperforate main body portion, a grill portion affording fluid flow communication between said display space and said evaporator assembly portion, said grill portion includes a first set of spaced apart, substantially vertical parallel walls and a second set of spaced apart, substantially nonvertical parallel walls which interconnect with said first set of walls to form a plurality of openings, wherein said main body portion and said grill like portion are formed as a single piece of filled polypropylene injection molded plastic, said cover including a first side defining a first tab having a recessed upper surface and said cover including a second side defining a second tab having a recessed underside and being adapted to be engaged by the first side of a second cover to define therebetween a lap joint.
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Name |
Date |
Kind |
4431905 |
Slocum |
Feb 1984 |
|
5727859 |
Jeong et al. |
Mar 1998 |
|