U.S. patent application number 11/426344 was filed with the patent office on 2007-01-18 for ambient air curtain with floor air inlet.
This patent application is currently assigned to HUSSMANN CORPORATION. Invention is credited to Sesha C. Madireddi, John M. Roche.
Application Number | 20070012059 11/426344 |
Document ID | / |
Family ID | 37056564 |
Filed Date | 2007-01-18 |
United States Patent
Application |
20070012059 |
Kind Code |
A1 |
Roche; John M. ; et
al. |
January 18, 2007 |
AMBIENT AIR CURTAIN WITH FLOOR AIR INLET
Abstract
A refrigerated merchandiser that includes a case defining a
product display area. The case includes a base supported by a
support surface that includes a primary inlet and a secondary inlet
disposed outside of the primary inlet that receives air from
adjacent the support surface. A canopy disposed substantially above
the product display area includes a primary outlet and a secondary
outlet. A primary air passageway fluidly connects the primary inlet
with the primary outlet and defines a primary air curtain that
flows across an open face portion of the case. A secondary air
passageway fluidly connects the secondary inlet with the secondary
outlet and defines a secondary air curtain that flows across the
open face portion outside of the primary air curtain. An evaporator
is located in the primary air passageway to refrigerate the primary
air curtain.
Inventors: |
Roche; John M.; (Ballwin,
MO) ; Madireddi; Sesha C.; (Saint Charles,
MO) |
Correspondence
Address: |
MICHAEL BEST & FRIEDRICH, LLP
100 E WISCONSIN AVENUE
MILWAUKEE
WI
53202
US
|
Assignee: |
HUSSMANN CORPORATION
12999 St. Chales Rock Road
Bridgeton
MO
|
Family ID: |
37056564 |
Appl. No.: |
11/426344 |
Filed: |
June 26, 2006 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60698395 |
Jul 12, 2005 |
|
|
|
Current U.S.
Class: |
62/256 ;
62/251 |
Current CPC
Class: |
A47F 3/0447
20130101 |
Class at
Publication: |
062/256 ;
062/251 |
International
Class: |
A47F 3/04 20060101
A47F003/04 |
Claims
1. A refrigerated merchandiser comprising: a case defining a
product display area including an open face portion, the case
including a base disposed below the product display area and
supported by a support surface, the base having a primary inlet
adjacent the product display area and a secondary inlet disposed
outside of the primary inlet, the secondary inlet configured to
receive air substantially adjacent the support surface, a canopy
disposed substantially above the product display area, the canopy
having a primary outlet adjacent the product display area and a
secondary outlet disposed outside of the primary outlet, a primary
air passageway fluidly connecting the primary inlet with the
primary outlet, the primary air passageway configured to direct a
primary airflow out of the primary outlet and across the open face
portion to define a primary air curtain adjacent the product
display area, a secondary air passageway fluidly connecting the
secondary inlet with the secondary outlet, the secondary air
passageway configured to direct a secondary airflow out of the
secondary outlet and across the open face portion to define a
secondary air curtain outside of the primary air curtain; and an
evaporator disposed in the primary air passageway to refrigerate
the primary air flow.
2. The refrigerated merchandiser of claim 1, further comprising a
primary fan disposed within the primary air passageway and
configured to generate the primary airflow, and a secondary fan
disposed within the secondary air passageway and configured to
generate the secondary airflow.
3. The refrigerated merchandiser of claim 1, further comprising a
louver attached to the secondary outlet.
4. The refrigerated merchandiser of claim 1, further comprising a
first louver attached to the primary outlet, and a second louver
attached to the secondary outlet.
5. The refrigerated merchandiser of claim 1, wherein the primary
inlet is configured to receive a substantial portion of the primary
air curtain, and wherein the secondary inlet is configured to
receive a substantial portion of the secondary air curtain.
6. The refrigerated merchandiser of claim 1, wherein the case
further includes an insulated wall disposed along at least a
portion of the primary air passageway and at least a portion of the
secondary air passageway.
7. The refrigerated merchandiser of claim 1, wherein a portion of
the secondary air passageway is defined by the support surface.
8. The refrigerated merchandiser of claim 1, wherein the primary
inlet is configured to receive air in a substantially vertical
direction, and wherein the secondary inlet is configured to receive
air in a substantially horizontal direction.
9. The refrigerated merchandiser of claim 1, wherein the primary
air curtain is directed along a first flow path, and wherein the
secondary air curtain is directed along a second flow path that is
substantially parallel to the first flow path.
10. The refrigerated merchandiser of claim 1, wherein the secondary
airflow is warmer than the primary airflow and cooler than ambient
air surrounding the refrigerated merchandiser.
11. The refrigerated merchandiser of claim 1, wherein the base
includes a substantially vertical panel extending upwardly from the
support surface, and wherein the secondary inlet is disposed on the
vertical panel.
12. A method of operating a refrigerated merchandiser including a
case having a base and a canopy, the method comprising: drawing air
adjacent a product display area into a primary inlet of the base;
moving a primary airflow from the primary inlet, through a primary
air passageway of the case, and to a primary outlet of the canopy
adjacent the product display area; discharging the primary airflow
through the primary outlet; generating a primary air curtain
adjacent a product display area with the primary airflow discharged
through the primary outlet; drawing air adjacent the support
surface into a secondary inlet of the base disposed outside of the
primary inlet; moving a secondary airflow from the secondary inlet,
through a secondary air passageway of the case, and to a secondary
outlet of the canopy disposed outside of the primary outlet;
discharging the secondary airflow through the secondary outlet; and
generating a secondary air curtain outside of the primary air
curtain with the secondary airflow through the secondary
outlet.
13. The method of claim 12, further comprising refrigerating the
primary airflow.
14. The method of claim 13, further comprising positioning the
secondary outlet adjacent an end of the canopy and providing a
secondary air curtain that is warmer than the primary air
curtain.
15. The method of claim 12, wherein drawing air into the primary
inlet includes drawing a substantial portion of the primary air
curtain.
16. The method of claim 12, wherein drawing air into the secondary
inlet includes drawing a substantial portion of the secondary air
curtain.
17. The method of claim 12, further comprising separating at least
a portion of the primary air passageway from at least a portion of
the secondary air passageway with an insulated wall.
18. The method of claim 18, wherein separating at least a portion
of the primary air passageway includes separating substantially the
entire primary air passageway from the secondary air passageway
with an insulated wall.
19. The method of claim 12, further comprising defining a portion
of the secondary air passageway with the support surface.
20. The method of claim 12, wherein drawing air into the primary
inlet includes drawing air in a substantially vertical direction,
and wherein drawing air into the secondary inlet includes drawing
air in a substantially horizontal direction.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims priority to U.S. Provisional
Application No. 60/698,395, filed on Jul. 12, 2005, the entire
contents of which are incorporated by reference herein.
BACKGROUND
[0002] The present invention relates to a refrigerated merchandiser
that includes a primary air passageway and a secondary air
passageway. More particularly, the present invention relates to a
refrigerated merchandiser that includes a primary air passageway
fluidly connecting a primary inlet adjacent a product display area
and a primary outlet in a canopy, and a secondary air passageway
fluidly connecting a secondary inlet adjacent a support surface and
a secondary outlet in the canopy.
[0003] In conventional practice, supermarkets and convenience
stores are equipped with refrigerated merchandisers having open
display portions for presenting fresh food or beverages in a
product display area to customers while maintaining the fresh food
and beverages (i.e., food product) in a refrigerated environment or
product display area. Typically, refrigerated merchandisers include
a curtain of cool, refrigerated air that passes downward across the
open face portion of the merchandiser to form a flowing boundary of
air between the product display area and the rest of the store. The
air curtain is generated by an airflow through a passageway of the
refrigerated merchandiser that is discharged from an outlet in a
canopy of the merchandiser, and is cooled by one or more
evaporators disposed in the passageway. The air curtain keeps
refrigerated air within the product display area to cool the food
product and protects the product display area from ambient air in
the surrounding store. Ambient conditions surrounding the
refrigerated merchandiser increase cooling requirements of the
merchandiser and can undesirably increase the temperature of the
food product in the product display area.
[0004] Some refrigerated merchandisers incorporate multiple air
curtains to limit entrainment of ambient air in a single air
curtain refrigerated merchandiser and to maintain the product
display area at desired temperatures. Turbulence exists at the
boundary between a single relatively high velocity air curtain and
the generally inactive ambient air lying in front of the display
case. The turbulence causes some ambient air to undesirably entrain
into the air curtain.
[0005] Refrigerated merchandisers with two or more adjacent,
parallel, but independently generated, air curtains include an
outer air curtain that has a slightly higher temperature than the
inner air curtain, so as to protect the colder, inner air curtain
from the impact of ambient air surrounding the merchandiser. The
inner air curtain is refrigerated by an evaporator. Typically, the
outer air curtain is formed from relatively warm, moisture-laden
air adjacent the top of the refrigerated merchandiser. The warm,
moisture-laden air is directed into an inlet adjacent an upper
portion of the refrigerated merchandiser and discharges the through
a second outlet in the canopy. Many refrigerated merchandisers do
not include an evaporator to cool air flowing through the second
passageway.
[0006] These multiple air curtain refrigerated merchandisers are
designed to limit problems of entrainment of ambient air into the
colder, inner air curtain. However, such designs do not completely
eliminate the intrusion of ambient air into the refrigerated air
curtain.
SUMMARY
[0007] In one embodiment, the invention provides a refrigerated
merchandiser that includes a case defining a product display area.
The case includes a base disposed below the product display area
and supported by a support surface, and a canopy disposed
substantially above the product display area. The base includes a
primary inlet adjacent the product display area and a secondary
inlet disposed outside of the primary inlet that receives air
substantially adjacent the support surface. The canopy includes a
primary outlet adjacent the product display area and a secondary
outlet disposed outside of the primary outlet. A primary air
passageway fluidly connects the primary inlet with the primary
outlet and directs a primary airflow out of the primary outlet and
across an open face portion of the case to define a primary air
curtain adjacent the product display area. A secondary air
passageway fluidly connects the secondary inlet with the secondary
outlet and directs a secondary airflow out of the secondary outlet
and across the open face portion to define a secondary air curtain
outside of the primary air curtain. An evaporator is disposed in
the primary air passageway to refrigerate the primary air flow.
[0008] In another embodiment the invention provides a method of
operating a refrigerated merchandiser including a case having a
base and a canopy. The method includes drawing air adjacent a
product display area into a primary inlet of the base, moving a
primary airflow from the primary inlet, through a primary air
passageway of the case, and to a primary outlet of the canopy
adjacent the product display area, discharging the primary airflow
through the primary outlet, and generating a primary air curtain
adjacent a product display area with the primary airflow discharged
through the primary outlet. The method also includes drawing air
adjacent the support surface into a secondary inlet of the base
disposed outside of the primary inlet, moving a secondary airflow
from the secondary inlet, through a secondary air passageway of the
case, and to a secondary outlet of the canopy disposed outside of
the primary outlet, discharging the secondary airflow through the
secondary outlet, and generating a secondary air curtain outside of
the primary air curtain with the secondary airflow through the
secondary outlet.
[0009] Other aspects of the invention will become apparent by
consideration of the detailed description and accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a perspective view of a refrigerated merchandiser
embodying the present invention.
[0011] FIG. 2 is a cross-sectional side view of the refrigerated
merchandiser of FIG. 1, exposing a primary air passageway defining
a primary air curtain and a secondary air passageway defining a
secondary air curtain.
[0012] FIG. 3 is a cross-sectional side view similar to FIG. 2,
illustrating a forward louver adjacent a secondary air passageway
of a refrigerated merchandiser according to another embodiment of
the invention.
[0013] FIG. 4 is a cross-sectional side view similar to FIG. 2,
illustrating a reverse louver adjacent a secondary air passageway
of a refrigerated merchandiser according to another embodiment of
the invention.
DETAILED DESCRIPTION
[0014] Before any 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 arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways. Also, it is to be understood that the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting. The use of "including,"
"comprising," or "having" and variations thereof herein is meant to
encompass the items listed thereafter and equivalents thereof as
well as additional items. Unless specified or limited otherwise,
the terms "mounted," "connected," "supported," and "coupled" and
variations thereof are used broadly and encompass both direct and
indirect mountings, connections, supports, and couplings. Further,
"connected" and "coupled" are not restricted to physical or
mechanical connections or couplings.
[0015] FIG. 1 shows a refrigerated merchandiser 10 that may be
located in a supermarket or a convenience store (not shown) for
presenting fresh food, beverages, and other food products (not
shown) to customers. The refrigerated merchandiser 10 includes a
case 15 having a base 20, a first interior rear wall 25, and a
canopy 30. The area partially enclosed by the base 20, the first
interior rear wall 25, and the canopy 30 defines a product display
area 35 having an open face portion 40 that allows customer access
to the food products stored in the case 15. The illustrated
embodiment shows the open face portion 40 disposed vertically
within the refrigerated merchandiser 10. Other embodiments may
include a horizontal case or coffin-style case defining a product
display area having an open face portion adjacent a top of the case
and disposed substantially horizontal within the refrigerated
merchandiser 10. One or more shelves 45 are disposed within the
product display area 35 to support the food products.
[0016] The base 20 is disposed substantially below the product
display area 35 and is supported by a floor or support surface 50
of the supermarket. Specifically, as shown in FIG. 2, a frame 55
disposed within the base 20 supports the case 15 on the support
surface 50. The frame 55 includes horizontal and vertical support
members 60 to provide structural support for the case 15 on the
support surface 50. The horizontal and vertical support members 60
are spaced apart from each other along the length of the base 20
providing clearance between adjacent support members 60.
[0017] FIG. 2 illustrates the refrigerated merchandiser 10 in
greater detail. The base 20 includes a first bottom wall 65, a
second bottom wall 70, a primary inlet 75, and a secondary inlet
80. The first bottom wall 65 defines a lower portion of the product
display area 35 and is configured to support a portion of the food
products. The illustrated second bottom wall 70 is an insulated
wall disposed below the first bottom wall 65. Other embodiments may
include the second bottom wall 70 without insulation.
[0018] The first bottom wall 65 and the second bottom wall 70
define a primary lower flue 85 to conduct a primary airflow 90
substantially horizontally through the base 20. The primary inlet
75 is in fluid communication with the primary lower flue 85 and is
disposed adjacent the open face portion 40 of the product display
area 35. The primary inlet 75 is positioned to receive surrounding
air in a substantially vertical direction and to direct the
surrounding air into the primary lower flue 85.
[0019] The second bottom wall 70 and the support surface 50 define
a secondary lower flue 95 to conduct a secondary airflow 100
substantially horizontally through the base 20 below the primary
airflow 90. The secondary inlet 80 is in fluid communication with
the secondary lower flue 95 and is disposed adjacent the support
surface 50. The secondary inlet 80 is positioned to receive
surrounding air in a substantially horizontal direction from
adjacent the support surface 50 and to direct the surrounding air
into the secondary lower flue 95. A grill or other cover 105 is
disposed over the secondary inlet 80 to at least partially conceal
portions of the frame 55 and to assist with directing surrounding
air into the secondary lower flue 95.
[0020] The first interior rear wall 25 defines a rear portion of
the product display area 35. The case 15 further includes an
exterior rear wall 110 and a second interior rear wall 115 disposed
between the first interior rear wall 25 and the exterior rear wall
110. A primary rear flue 120 is defined by the first interior rear
wall 25 and the second interior rear wall 115. The primary rear
flue 120 is in fluid communication with the primary lower flue 85
to direct the primary airflow 90 in a substantially vertical
direction. In some embodiments, the first interior rear wall 25 may
include apertures (not shown) to fluidly couple the primary rear
flue 120 with the product display area 35 and allow at least some
of the primary airflow 90 in the primary rear flue 120 to enter the
product display area 35.
[0021] The second interior rear wall 115 is an insulated wall
configured to buffer the primary airflow 90 from the secondary
airflow 100. Other embodiments may include the second interior rear
wall 115 without insulation.
[0022] The exterior rear wall 110 and the second interior rear wall
115 define a secondary rear flue 125. The secondary rear flue 125
is in fluid communication with the secondary lower flue 95 direct
the secondary airflow 100 in a substantially vertical
direction.
[0023] The canopy 30 includes a first interior top wall 130, an
exterior top wall 135, and a second interior top wall 140 disposed
between the first interior top wall 130 and the exterior top wall
135. The first interior top wall 130 defines a portion of the
product display area 35 and includes a primary outlet 145 and a
secondary outlet 150. The primary outlet 145 is disposed adjacent
the product display area 35 and the secondary outlet 150 is located
outward from the primary outlet 145 adjacent an end of the canopy
30. The first interior top wall 130 and the second interior top
wall 140 define a primary upper flue 155 that is fluidly connected
with and adjacent the primary rear flue 120. The primary upper flue
155 couples with the primary outlet 145 to direct the primary
airflow 90 in a substantially horizontal direction toward the
primary outlet 145.
[0024] The second interior top wall 140 is an insulated wall
configured to buffer the primary upper flue 155 from the secondary
upper flue 160. Other embodiments may include the second interior
top wall 140 without insulation.
[0025] The exterior top wall 135 and the second interior top wall
140 define a secondary upper flue 160 that is fluidly connected
with and adjacent the secondary rear flue 125. The secondary upper
flue 160 couples with the secondary outlet 150 to direct the
secondary airflow 100 in a substantially horizontal direction
toward the secondary outlet 150.
[0026] The primary lower flue 85, the primary rear flue 120, and
the primary upper flue 155 define a primary air passageway. The
primary air passageway is configured to direct the primary airflow
90 from the primary inlet 75 to the primary outlet 145, and to
discharge the primary airflow 90 from the primary outlet 145 in the
form of a primary air curtain 165. In the illustrated embodiment,
the primary air curtain 165 is directed downwardly across the open
face portion 40 adjacent the product display area 35 to cool the
food products. Other embodiments may include a horizontal case or
coffin-style case defining a product display area having an open
face portion adjacent a top of the case. In these embodiments, the
primary air curtain 165 is directed substantially horizontally
across the horizontally-disposed open face portion.
[0027] The secondary lower flue 95, the secondary rear flue 125,
and the secondary upper flue 160 define a secondary air passageway.
The secondary air passageway is configured to direct the secondary
airflow 100 from the secondary inlet 80 to the secondary outlet
150, and to discharge the secondary airflow 100 from the secondary
outlet 150 in the form of a secondary air curtain 170. The
secondary air curtain 170 is located adjacent and outside of the
primary air curtain 165 to assist in forming a barrier between
ambient air surrounding the case and the product display area 35.
The secondary air curtain 170 is warmer than the primary air
curtain 165 and cooler than the surrounding ambient air. In the
illustrated embodiment, the secondary air curtain 170 is directed
downward across the open face portion outside of the primary air
curtain 165 to buffer the primary air curtain 165 from the
relatively warm ambient air surrounding the case 15. In embodiments
that include a case having a horizontal open face portion the
secondary air curtain 170 is directed substantially horizontally
across the horizontal open face portion.
[0028] The primary and secondary air curtains 165, 170 cooperate to
define a dual air curtain that is configured to move across the
open face portion 40. Portions of the dual air curtain may be drawn
into one or both of the primary and secondary inlets for
recirculation. The dual air curtain, among other things, helps to
maintain the air temperature in the product display area within a
standard temperature range. For example, for medium temperature
cases the temperature range is 32 to 41 degrees Fahrenheit as
determined by the Food and Drug Administration ("FDA") Food
Code.
[0029] The refrigerated merchandiser 10 also includes some
components of a refrigeration system (not entirely shown) therein.
At least one fan 175 is located within the primary lower flue 85
toward the rear of the case 15 to generate the primary airflow 90
through the primary air passageway. The fan 175 draws air into the
primary air passageway from the primary inlet 75 and forces the air
through the remaining portions of the primary air passageway. The
illustrated embodiment shows one fan 175 positioned in the primary
lower flue 85 to generate the primary airflow. Other embodiments
may include more than one fan 175 to generate the primary airflow
90 through the primary air passageway. In still other embodiments
the fan 175 may be located in the primary rear flue 120 or in the
primary upper flue 155.
[0030] A second fan 180 is disposed in the secondary air passageway
to generate the secondary airflow 100. The illustrated embodiment
shows the fan 180 positioned within the secondary rear flue 125
adjacent a rear upper portion of the case 15. The fan 180 draws air
into the secondary air passageway through the secondary inlet 80
from adjacent the support surface 50 and forces air through the
secondary outlet 150. The illustrated embodiment shows one fan 180
positioned in the secondary air passageway. Other embodiments may
include more than one fan 180 to generate the secondary airflow 100
through the secondary air passageway. Still other embodiments may
include one or more fans 180 extending across the length of the
case 15 located in the secondary rear flue 125, in the secondary
lower flue 95, or other positions within the case 15 that generate
the secondary airflow 100.
[0031] An evaporator 185 is located within the primary rear flue
120 and downstream of the fan 175 to refrigerate the primary
airflow 90. The evaporator 185 is configured to receive a saturated
refrigerant that has passed through an expansion valve (not shown).
As is known in the art, the saturated refrigerant is evaporated as
it passes through the evaporator 185 as a result of absorbing heat
from the primary airflow 90 passing over the evaporator 185. The
absorption of heat by the refrigerant allows the temperature of the
primary airflow 90 to decrease as it passes over the evaporator
185. The heated or gaseous refrigerant then exits the evaporator
185 and is pumped back to remotely located compressor(s) (not
shown) for re-processing into the refrigeration system. In other
embodiments, the evaporator 185 may be located in the primary lower
flue 85 upstream of the fan 175 to refrigerate the primary airflow
90. In still other embodiments, more than one evaporator 185 may be
located in the primary air passageway to refrigerate the primary
airflow 90.
[0032] FIGS. 3 and 4 show embodiments of the refrigerated
merchandiser 10 including a louver 190 positioned adjacent the
secondary outlet 150 to direct the secondary air curtain 170 across
the open face portion 40. The louver 190 includes a plurality of
substantially parallel, elongated fins and a unitary body as
described in Hussmann's U.S. patent application Ser. No.
11/059,617, filed on Feb. 16, 2005 (Entitled AIR LOUVER FOR A
REFRIGERATED DISPLAY CASE). The louver 190 is positioned within the
case 15 such that the secondary airflow 100 through the louver 190
is directed substantially orthogonal to the direction of the
secondary airflow through the secondary upper flue 160. The louver
190 includes channels 195 that define an inlet profile to
facilitate the change in direction of the secondary airflow 100. In
other embodiments, one or more louvers 190 may be located adjacent
the primary outlet 145 and the secondary outlet 150 to direct the
primary and secondary air curtains 165, 170 across the open face
portion 40. In still other embodiments, the louver 190 may be
positioned adjacent the primary outlet 145 without a second louver
190 adjacent the secondary outlet 150.
[0033] FIG. 3 shows one embodiment of the refrigerated merchandiser
10 that includes the louver 190 positioned in a forward direction
extending across the secondary outlet 150. The channels 195
generally increase in length and decrease in width in the direction
of flow of the secondary airflow 100 through the secondary upper
flue 160. This configuration of the channels 195 from an inner
portion of the secondary outlet 150 adjacent the primary outlet 145
to an outer portion of the secondary outlet 150 adjacent the end of
the canopy 30 causes a portion of the secondary air curtain 170
adjacent the primary air curtain 165 to be slower than a portion of
the secondary air curtain 170 adjacent the end of the canopy 30. In
other words, the forward louver 190 defines an increasing variable
flow rate of a cross-section of the secondary air curtain 170 taken
from adjacent the primary air curtain 165 toward the end of the
canopy 30 (i.e., outward direction away from the product display
area 35). The increasing variable flow rate provides a
substantially uniform and relatively low-temperature flow of air to
buffer the primary air curtain 165 and maintains a relatively cool
dual air curtain across a substantial portion of the open face
portion 40. In embodiments including the louver 190 disposed
adjacent the primary outlet 145, the forward louver 190 facilitates
a substantially uniform low-temperature primary air curtain 165 to
cool the product display area.
[0034] FIG. 4 illustrates another embodiment of the refrigerated
merchandiser 10 that includes the louver 190 positioned in a
reverse direction extending across the secondary outlet 150. The
channels 195 of the reverse louver 190 generally decrease in length
and increase in width in the direction of flow of the secondary
airflow 100 through the secondary upper flue 160. The decreasing
length of the channels 195 across the secondary outlet 150 causes
an inner portion of the secondary air curtain 170 adjacent the
primary air curtain 165 to be faster than an outer portion of the
secondary air curtain 170 adjacent the end of the canopy 30,
defining a decreasing variable flow rate of a cross-section of the
secondary air curtain 170 in the outward direction away from the
product display area 35. The decreasing variable flow rate provides
a substantially uniform flow of air across the open face portion 40
to buffer the primary air curtain 165 and maintains a relatively
cool dual air curtain across a substantial portion of the open face
portion 40.
[0035] Referring back to FIG. 2, the illustrated refrigerated
merchandiser 10 includes the case 15 without the louver 190 located
adjacent the primary and secondary outlets 145, 150. The primary
and secondary air curtains 165, 170 are directed across the open
face portion 40 without a substantially variable flow rate profile
as described with regard to FIGS. 3 and 4. The largely unchanging
airflow velocity profiles of the primary and secondary air curtains
165, 170 respectively cool the product display area 35 and buffer
the primary air curtain 165 from warm ambient air surrounding the
refrigerated merchandiser 10.
[0036] Activation of the first and second fans 175, 180 draws air
into the respective primary and secondary air passageways. With
regard to the primary air passageway, air is drawn into the primary
lower flue 85 through the primary inlet 75. The primary air curtain
165 is directed generally toward the primary inlet 75, and a
substantial portion of the primary air curtain 170 is received by
the primary inlet 75 to be recycled through the case 15. Recycling
the primary air curtain 165 recirculates cool air to effectively
cool the product display area 35. The primary airflow 90 generated
by the first fan 175 is cooled by the evaporator 190 and discharges
from the primary outlet 145 and flows across the open face portion
40, cooling the product display area 35 and maintaining the food
products at FDA-recommended temperatures.
[0037] The secondary inlet 80 draws relatively cool, dry air from
adjacent the support surface 50 into the secondary air passageway.
The secondary air curtain 170 is directed across the open face
portion 40 outside of the primary air curtain 170 and flows
generally toward the secondary inlet 80. The secondary inlet 80
receives at least a portion of the secondary air curtain 170 that
is recycled through the case 15. The secondary airflow 100 flows
through the secondary air passageway with the assistance of the
second fan 180 and discharges through the secondary outlet 150
outside of the primary outlet 145. The cool, dry secondary air
curtain 170 provides an effective buffer for the primary air
curtain 165 without substantially decreasing the cooling effect of
the primary air curtain 165. Drawing cool, dry air into the
secondary air passageway and discharging the cool, dry air from the
secondary outlet 150 effectively maintains a temperature of the
secondary air curtain 170 that is warmer than the primary air
curtain 165, but cooler than ambient air surrounding the
refrigerated merchandiser 10.
[0038] Thus, the invention provides, among other things, a
refrigerated merchandiser that includes a primary air curtain
defined by a primary airflow that receives air from adjacent a
product display area and a secondary air curtain defined by a
secondary airflow receiving air from adjacent a support surface.
Various features and advantages of the invention are set forth in
the following claims.
* * * * *