U.S. patent application number 10/978475 was filed with the patent office on 2005-05-12 for open showcase.
This patent application is currently assigned to Sanden Corporation. Invention is credited to Kanbayashi, Nobuo, Kasuya, Junichiro, Nakajima, Sakae, Ochiai, Masaru, Takei, Takahiro.
Application Number | 20050097910 10/978475 |
Document ID | / |
Family ID | 34544701 |
Filed Date | 2005-05-12 |
United States Patent
Application |
20050097910 |
Kind Code |
A1 |
Nakajima, Sakae ; et
al. |
May 12, 2005 |
Open showcase
Abstract
The invention is intended to provide an open showcase which
allows efficient displaying of frozen and refrigerated foods even
in a retail store with a limited sales floor space. Thus, the open
showcase, as it comprises a lower showcase whose top face is open
and an upper showcase which is arranged above and at a prescribed
distance from the top face of the lower showcase, is enabled to
display frozen foods in the lower showcase and refrigerated foods
in the upper showcase. For instance, frozen foods such as ice cream
and sherbet and refrigerated items such as custard pudding and
yogurt can be displayed at the same time in a single showcase.
Accordingly goods can be efficiently displayed even in a retail
store having only a limited sales floor space.
Inventors: |
Nakajima, Sakae; (Sawa-gun,
JP) ; Kanbayashi, Nobuo; (Kodama-gun, JP) ;
Ochiai, Masaru; (Ashikaga-shi, JP) ; Kasuya,
Junichiro; (Isesaki-shi, JP) ; Takei, Takahiro;
(Takasaki-shi, JP) |
Correspondence
Address: |
BANNER & WITCOFF
1001 G STREET N W
SUITE 1100
WASHINGTON
DC
20001
US
|
Assignee: |
Sanden Corporation
Isesaki-shi
JP
|
Family ID: |
34544701 |
Appl. No.: |
10/978475 |
Filed: |
November 2, 2004 |
Current U.S.
Class: |
62/256 ; 62/246;
62/458 |
Current CPC
Class: |
A47F 3/0443
20130101 |
Class at
Publication: |
062/256 ;
062/246; 062/458 |
International
Class: |
A47F 003/04; F25D
013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 12, 2003 |
JP |
382559/2003 |
Claims
What is claimed is:
1. An open showcase comprising: a lower showcase whose top face is
open, a cooler for cooling the inner space of the lower showcase,
an upper showcase which is arranged above and at a distance from
the top face of the lower showcase and whose front and rear faces
are open, and a cooler for cooling the inner space of the upper
showcase.
2. The open showcase according to claim 1, wherein: said lower
showcase comprises a lower showcase body, an air duct formed along
the front, rear and bottom sides of the lower showcase body, and an
air blower arranged together with a cooler within the air duct; and
air sucked through one end in the lengthwise direction of the
opening in the top face of the lower showcase into the air duct is
cooled by the cooler, and the air cooled by the cooler is
discharged toward that one end in the lengthwise direction of the
opening in the top face from the other end.
3. The open showcase according to claim 1, wherein: said upper
showcase is supported by a pair of supporting members extending
upward from the right and left sides of the lower showcase.
4. The open showcase according to claim 1, wherein: said upper
showcase comprises an upper showcase body, an air duct formed along
the bottom side of the upper showcase body, an air blower arranged
together with said cooler within the air duct, and a current plate
disposed in the central part in the lengthwise direction of the top
face side of the upper showcase body; and air sucked through the
lower end sides of the front side opening and the rear side opening
of the upper showcase body into the air duct is cooled by the
cooler and discharged upward from the central part in the
lengthwise direction of the air duct, and at the same time is
divided by the current plate toward the forward and backward faces
of the upper showcase body.
5. The open showcase according to claim 4, wherein: the air blower
of the upper showcase is arranged the central part in the
lengthwise direction of the air duct, and one each of said cooler
is disposed before and behind the air blower.
6. The open showcase according to claim 4, wherein: a partitioning
plate to divide the space inside said upper showcase body in the
lengthwise direction is provided, and air discharged from an air
blow-off port is caused to circulate upward along the front and
rear faces of the partitioning plate.
7. The open showcase according to claim 5, wherein: a partitioning
plate to divide the space inside said upper showcase body in the
lengthwise direction is provided, and air discharged from an air
blow-off port is caused to circulate upward along the front and
rear faces of the partitioning plate.
8. The open showcase according to claim 4, wherein: an illuminating
device is disposed on the under face in the central part in the
lengthwise direction of said current plate.
9. The open showcase according to claim 8, wherein: said
illuminating device is provided with an illumination cover whose
front and rear faces are inclined obliquely upward.
10. The open showcase according to claim 1, wherein: the lower
showcase body is provided with a machinery compartment to suck
external air from the lower part of the front face of said lower
showcase body and discharge from the lower part of the rear face,
and a forced draft unit to cause air descending from the rear side
opening of said upper showcase to circulate along the under face of
the upper showcase toward the front of the lower showcase.
11. The open showcase according to claim 10, wherein: said forced
draft unit comprises a duct to blow air sucked from the rear side
of the upper showcase toward the front side, and an air blower
arranged within the duct.
12. The open showcase according to claim 1, further provided with:
a forced draft unit which blows air from the under face of the
upper showcase toward the front and rear sides of the lower
showcase against air flows descending from the front and rear
openings of said upper showcase.
13. The open showcase according to claim 12, wherein: said forced
draft unit comprises a duct to blow air toward the front and rear
sides of the upper showcase and an air blower arranged within the
duct.
14. The open showcase according to claim 10, further provided with:
a temperature detector for detecting the temperature within the
lower showcase, and a control unit for controlling the air flow
rate of said forced draft unit on the basis of temperatures
detected by the temperature detector.
15. The open showcase according to claim 12, further provided with:
a temperature detector for detecting the temperature within the
lower showcase, and a control unit for controlling the air flow
rate of said forced draft unit on the basis of temperatures
detected by the temperature detector.
16. The open showcase according to claim 10, further provided with:
temperature detector for detecting the temperature in the
vicinities of the lower showcase, and a control unit for
controlling the air flow rate of said forced draft unit on the
basis of temperatures detected by the temperature detector.
17. The open showcase according to claim 12, further provided with:
a temperature detector for detecting the temperature in the
vicinities of the lower showcase, and a control unit for
controlling the air flow rate of said forced draft unit on the
basis of temperatures detected by the temperature detector.
18. The open showcase according to claim 10, further provided with:
an air velocity detector for detecting the velocities of air
flowing out of the openings in the lower showcase, and a control
unit for controlling the air flow rate of said forced draft unit on
the basis of the air velocities detected by the air velocity
detector.
19. The open showcase according to claim 12, further provided with:
an air velocity detector for detecting the velocities of air
flowing out of the openings in the lower showcase, and a control
unit for controlling the air flow rate of said forced draft unit on
the basis of the air velocities detected by the air velocity
detector.
Description
BACKGROUND OF THE INVENTION
[0001] (i) Field of the Invention
[0002] The present invention relates to an open showcase to be
installed in retail stores including supermarkets and convenience
stores for the storage of frozen or refrigerated foods.
[0003] (ii) Description of the Related Art
[0004] Known conventional open showcases of this kind include one
comprising a showcase body whose top side is open, an air duct
formed along the front, bottom and rear sides of the showcase body,
and a cooler and an air blower arranged within the air duct, in
which an air curtain is formed in the opening of the top face by
air sucked through an air intake disposed toward the front end of
the showcase body, cooled by the cooler and discharged through an
air outlet disposed toward the rear end of the opening of the top
face of the showcase body. Frozen or refrigerated foods are
preserved at low temperature in the showcase body.
[0005] However, according to the configuration of this conventional
open showcase, where frozen foods such as ice cream and sherbet and
refrigerated items such as custard pudding and yogurt are to be
stored in a retail store space, a freezer showcase and a
refrigerator showcase should be separately installed. In a retail
store with a limited sales floor space, difficulty is very likely
to be experienced in efficiently displaying such foods.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provide an open
showcase which allows efficient displaying of both frozen and
refrigerated foods even in a retail store with a limited sales
floor space.
[0007] In order to achieve the object stated above, an open
showcase according to the invention comprises a lower showcase
whose top face is open, a cooler for cooling the inner space of the
lower showcase, an upper showcase which is arranged above and at a
distance from the top face of the lower showcase and whose front
and rear faces are open, and another cooler for cooling the inner
space of the upper showcase.
[0008] It is thereby enabled, for instance, to display frozen foods
in the lower showcase and refrigerated foods in the upper showcase.
In this case, since the upper showcase is arranged above the lower
showcase, no extra installation space is required. Therefore, as it
is possible to display frozen foods in the lower showcase and
refrigerated foods in the upper showcase, frozen foods such as ice
cream and sherbet and refrigerated items such as custard pudding
and yogurt can be displayed at the same time in a single showcase
for instance. Accordingly goods can be efficiently displayed even
in a retail store having only a limited sales floor space.
[0009] Also in the foregoing configuration according to the
invention, the lower showcase body may be provided with a machinery
compartment to suck external air from the lower part of the front
face of the lower showcase body and discharged from the lower part
of the rear face, and forced draft unit may be further provided to
cause air descending from the rear side opening of the upper
showcase to circulate along the under face of the upper showcase
toward the front of the lower showcase.
[0010] This makes it possible, in addition to the above-described
effect, to prevent air on the upper showcase side from falling onto
the top face of the lower showcase because the air descending from
the rear side opening of the upper showcase is caused by the forced
draft unit to circulate along the under face of the upper showcase
toward the front of the lower showcase. Therefore, even where cold
air having overflowed the air curtains formed on the upper showcase
and external air cooled by contact with the air curtains descend
toward the upper face of the lower showcase body, air on the upper
showcase side does not fall onto the top face of the lower
showcase. Therefore, disturbance of the air curtain of the lower
showcase can be prevented without fail.
[0011] The aforementioned and other objects, features and
advantages of the present invention will become more apparent from
the following description when taken in conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows a perspective view of an open showcase, which
is a first preferred embodiment of the present invention;
[0013] FIG. 2 shows a front view of the open showcase;
[0014] FIG. 3 shows a side sectional view of the open showcase;
[0015] FIG. 4 shows a front view of an open showcase, which is a
second preferred embodiment of the invention;
[0016] FIG. 5 shows a side sectional view of the open showcase;
[0017] FIG. 6 is a block diagram showing the control system of the
open showcase;
[0018] FIG. 7 is a flow chart showing the operation of the open
showcase;
[0019] FIG. 8 shows a side sectional view of the open showcase in
which a duct is formed;
[0020] FIG. 9 shows a front view of an open showcase, which is a
third preferred embodiment of the invention;
[0021] FIG. 10 shows a side sectional view of the open
showcase;
[0022] FIG. 11 shows an open showcase with a built-in freezing
machine having no forced draft unit disposed in the lower part of
the upper showcase;
[0023] FIG. 12 shows an open showcase with a separate external
freezing machine having no forced draft unit disposed in the lower
part of the upper showcase;
[0024] FIG. 13 shows a side sectional view of an open showcase with
a built-in freezing machine having temperature detectors in the
vicinities of the lower showcase;
[0025] FIG. 14 shows a side sectional view of an open showcase with
a separate external freezing machine having temperature detectors
in the vicinities of the lower showcase;
[0026] FIG. 15 shows a side sectional view of an open showcase with
a built-in freezing machine having air velocity detectors in the
vicinities of the lower showcase; and
[0027] FIG. 16 shows a side sectional view of an open showcase with
a separate external freezing machine having air velocity detectors
in the vicinities of the lower showcase.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] FIG. 1 through FIG. 3 show a first preferred embodiment of
the present invention.
[0029] This open showcase comprises a lower showcase 10 whose top
face is open, and an upper showcase 20 which is arranged above and
at a distance from the top face of the lower showcase 10 and whose
front and rear faces are open.
[0030] The lower showcase 10 is provided with a lower showcase body
11 whose front, right, left, rear and bottom sides are surrounded
by thermally insulating walls, an air duct 11a formed along the
front, rear and bottom sides within the lower showcase body 11, an
air blower 11b and a cooler 11c arranged within the air duct 11a,
an intake 11d disposed toward the front end of the opening in the
top face of the lower showcase body 11, and a blow-off port 11e
disposed toward the rear end of the opening in the top face of the
lower showcase body 11.
[0031] A machinery compartment 12 is disposed in the lower part of
the lower showcase body 11, and a condenser 12a, a condenser
cooling blower 12b and a compressor 12c are housed in the machinery
compartment 12. An intake 12d to suck external air is disposed in
the lower part of the front face of the lower showcase 10, and an
outlet 12e to discharge air is disposed in the lower part of the
rear face of the machinery compartment 12.
[0032] The upper showcase 20 is configured of an upper showcase
body 21 to mount foods on, a pair of right and left supporting
members 22 to support the upper showcase body 21, a current plate
23 constituting the central part of the top face of the upper
showcase 20, and a pair of side plates 24 arranged on the right and
left sides of the upper showcase body 21.
[0033] The upper showcase body 21, whose bottom side is formed of a
thermally insulating wall, is built smaller than the lower showcase
10 in the front-to-rear dimension. The upper showcase body 21 is
provided with an air duct 21a formed along the bottom side within
the upper showcase body 21, a pair of coolers 21b, of which one
each is arranged on the front and rear sides within the air duct
21a, an air blower 21c arranged between the front side cooler 21b
and the rear side cooler 21b, a pair of intakes 21d disposed toward
the lower ends of the front and rear side openings, a blow-off port
21e disposed at the center in the lengthwise direction, and a
transparent resin-made partitioning plate 21f dividing the blow-off
port 21e in the lengthwise direction.
[0034] The under face of the upper showcase body 21 is inclined
toward the center from the front and rear faces so that foods in
the lower showcase 10 can be easily taken out. Fluorescent lamps
21g to illuminate the lower showcase 10 from above, extending in
the widthwise direction, are arranged at the lower end of the upper
showcase body 21.
[0035] Each of the supporting members 22 extends upward from the
upper end of the right or left side of the lower showcase body 11,
and supports the right or left end of the upper showcase body
21.
[0036] The current plate 23 is so formed as to extend in the
widthwise direction of the lower showcase 20, and its two ends in
the lengthwise direction are bent obliquely downward. At the center
in the lengthwise direction of the under face of the current plate
23, a fluorescent lamp 23a is arranged extending in the widthwise
direction. The fluorescent lamp 23a is shielded by an illumination
cover 23b whose section has an inverted triangular shape.
[0037] Each of the side plates 24 is formed of a glass sheet
extending upward from the right or left side of the lower showcase
body 11, and the plates shield all of the upper showcase body 21
and the current plate 23 from the right and left sides.
[0038] In the open showcase configured as described above, air
sucked by the air blower 11b of the lower showcase 10 through the
intake 11d flows into the air duct 11a and, after being cooled by
the cooler 11c, is discharged through the blow-off port 11e. This
causes cooled air to flow from the rear side to the front side of
the opening of the top face of the lower showcase 10 to constitute
an air curtain A.
[0039] In the upper showcase 20, air sucked by the air blower 21c
through the intakes 21d flows into the air duct 21a and, after
being cooled by the coolers 21b, is divided by the partitioning
plate 21f into the forward and backward directions and blown out
upward from the blow-off port 21e. The air currents blown upward
flow along the illumination cover 23b fitted to the under face of
the current plate 23 and the under face of the current plate 23,
and air curtains B are formed from the upper end toward the lower
end of the front and rear openings.
[0040] In the open showcase embodying the invention in this mode,
it comprises the lower showcase 10 whose top face is open and the
upper showcase 20 arranged above and at a distance from the top
face of the lower showcase 10. Therefore, it allows displaying of
refrigerated foods in the upper showcase 20 while displaying frozen
foods in the lower showcase 10. For instance, while frozen foods
such as ice cream and sherbet and refrigerated items such as
custard pudding and yogurt can be displayed at the same time in a
single showcase, and accordingly goods can be efficiently stored
even in a retail store having only a limited sales floor space.
[0041] Also, the effectiveness of product display and service
convenience can be enhanced without sacrificing the visibility and
access to goods in the lower showcase 10, as the upper showcase 20
is supported by the supporting members 22 extending upward from the
upper ends of the right and left sides of the lower showcase
10.
[0042] Further, the space within the upper showcase 20 can be
uniformly cooled because air sucked through the intakes 21d,
disposed toward the lower ends of the openings in the front and
rear faces of the upper showcase 20, into the air duct 21a is
cooled by the coolers 21b and, after being discharged upward
through the blow-off port 21e disposed at the center in the
lengthwise direction of the upper showcase body 21, is caused to
circulate in the lengthwise direction along the under face of the
current plate 23.
[0043] Also, the installation space of the air blower 21c can be
reduced and the upper showcase 20 made more compact, as the coolers
21b are disposed on the front and rear sides of the upper showcase
20 and the air blower 21c are arranged between the coolers 21b.
[0044] Further, as the space in the upper showcase body 21 is
divided into the front and rear parts by the partitioning plate
21f, it is possible to divide the air discharged from the blow-off
port 21e into a forward flow and a backward flow, and therefore to
prevent air discharged from an air-conditioner or the like, for
instance, within the store from disturbing the air in the upper
showcase body 21.
[0045] The presence of the fluorescent lamp 23a on the under face
of the current plate 23 makes it possible to brightly illuminate
foods arranged in the upper showcase 20 and thereby enhance the
displaying effect.
[0046] The use of the illumination cover 23b having an inverted
triangular-shaped section to shield the fluorescent lamp 23a makes
it possible to guide the discharged air along the illumination
cover 23b toward the front and rear sides and thereby to ensure
smooth air circulation without disturbing the air in the upper
showcase 20.
[0047] FIG. 4 through FIG. 7 show a second preferred embodiment of
the present invention. Equivalent constituent elements to their
counter parts in the first preferred embodiment are denoted by
respectively the same reference signs.
[0048] In the first embodiment, as shown in FIG. 11, there may
occasionally occur a case in which cold air having overflowed air
curtains B formed in the upper showcase 20 and external air cooled
by contact with the air curtains B descend from the upper showcase
20, and these air flows C are induced by the air blown behind the
machinery compartment 12 to cause the air curtain A of the lower
showcase 10 to be disturbed by its contact with the airflows C. In
view of this problem, the open showcase of this second embodiment
has air blowers 30, the counterpart of which in the open showcase
of the first embodiment is disposed on the under face of the upper
showcase 20, and a control unit 40 for controlling the air flow
rate of the air blowers 30.
[0049] A plurality of the air blowers 30 are arranged at prescribed
intervals in the widthwise direction at the lower end of the upper
showcase body 21, and underneath them there are arranged the
fluorescent lamps 21g, extending in the widthwise direction, to
illuminate the lower showcase 10 from above.
[0050] The control unit 40, consisting of a microcomputer, is
connected to the air blower 30 and a temperature detector 41
disposed within the air duct 11a of the lower showcase 10.
[0051] In this open showcase, cold air having overflowed the air
curtains B of the front and rear faces of the upper showcase 20 and
external air cooled by contact with the air curtains B descend
along the under face of the upper showcase body 21. These
descending air flows C are caused by the air blower 30 to circulate
toward the front side of the lower showcase 10 and sucked into the
intake 12d of the machinery compartment 12.
[0052] Next, the operation of the control unit 40 will be described
with reference to the flow chart of FIG. 7.
[0053] First, when the temperature in the air duct 11a of the lower
showcase 10 is at or above a prescribed set temperature T1 (S1),
the air flow rate of the air blower 30 is set to its maximum (S2).
Or when the temperature in the air duct 11a is below the prescribed
set temperature T1 (S1) and at a prescribed set temperature T2 (S3)
or lower, the air flow rate of the air blower 30 is set to its
minimum (S4). Or when the temperature in the air duct 11a is below
the prescribed set temperature T1 (S1) but higher than the
prescribed set temperature T2 (S3), the air flow rate of the air
blower 30 is set to a prescribed medium rate between the maximum
and the minimum (S5).
[0054] As described above, in the open showcase of this embodiment,
the air flows C descending from the opening in the rear face of the
upper showcase 20 are caused to circulate toward the front side of
the lower showcase 10. Therefore, air on the upper showcase 20 does
not descend onto the top face of the lower showcase 10, thereby
making it possible to prevent the air curtain A of the lower
showcase 10 from being disturbed without fail. Moreover, as the air
flows C descending from the upper showcase 20 can be used for
cooling the condenser 12a, the efficiency of cooling can be
enhanced.
[0055] There are further provided the temperature detector 41 for
detecting the temperature in the lower showcase 10 and the control
unit 40 for controlling the air flow rate of the air blower 30 on
the basis of temperatures detected by the temperature detector 41.
As the air flow rate is thereby increased when the detected
temperature is high, or reduced when the detected temperature is
low, the optimum air flow can be formed all the time, unaffected by
any change in the environment in which the open showcase is
installed or by any like factor.
[0056] Although air on the under face side of the upper showcase 20
is caused to flow only by the air blowers 30 in the embodiment
described here, it is also conceivable to form a duct 31 on the
under face of the upper showcase 20 as shown in FIG. 8 and to
arrange the air blowers 30 within the duct 31. In this case, as it
is possible to have the air flows C descending from the upper
showcase 20 sucked into the duct 31 and discharged forward, the air
flow in the lengthwise direction along the under face of the upper
showcase 20 can be smoothly formed by the duct 31, and the descent
of air to the air curtain A of the lower showcase 10 can be
prevented without fail.
[0057] Although an axial blower is used as the air blower 30 in the
second embodiment described above, a Silocco fan, a line flow fan
or the like can be used as well.
[0058] FIG. 9 and FIG. 10 show a third preferred embodiment of the
present invention. Equivalent constituent elements to their counter
parts in the first preferred embodiment are denoted by respectively
the same reference signs.
[0059] The open showcase of this embodiment has no freezing
equipment built into it, but is connected by copper piping to
external freezing equipment (not shown). In such an arrangement,
the air flows C descending from the air curtains B may fall on the
top face of the lower showcase 10 and disturb the air curtain A as
shown in FIG. 12. To cope with this problem, the forced draft unit
of this embodiment comprises a duct 32, so formed on the under face
of the upper showcase 20 as to blow air in the front and rear
directions, and an air blower 33 arranged within the duct 32.
[0060] In this open showcase, external air is taken in by the air
blower 33, and blown on the front and rear faces via the duct 32 on
the under face of the upper showcase 20. This arrangement causes
the air flows C descending from the air curtains B to go down,
together with the air blown out of the duct 32, onto the front and
rear faces of the lower showcase 10 instead of falling onto the top
face of the lower showcase 10 from the under side of the upper
showcase 20.
[0061] In the open showcase of this embodiment, air is blown from
the under face of the upper showcase 20 toward the front and rear
faces of the lower showcase against the air flows C descending from
the openings of the upper showcase 20. Therefore, the air flows C
descending from the upper showcase 20 are obstructed from falling
onto the top face of the lower showcase 10, and the disturbance of
the air curtain A of the lower showcase 10 can be prevented without
fail.
[0062] Further, as the forced draft unit is configured of the duct
32 and the air blower 33 by which air is blown from the under face
of the upper showcase 20 toward the front and rear faces of the
lower showcase against the air flows C descending from the openings
of the upper showcase 20, the air flows C descending from the upper
showcase 20 are obstructed from falling onto the top face of the
lower showcase 10, and the disturbance of the air curtain A of the
lower showcase 10 can be prevented without fail.
[0063] The temperature detector 41 is installed within the air duct
11a of the lower showcase 10 for the control of the air blowers 30
or 33 in the second and third embodiments described and illustrated
above. Instead, in an open showcase with a built-in freezing
machine, temperature detectors 41 may be disposed in the vicinities
of the openings in the front and rear faces of the lower showcase
10 to detect air flowing out of the lower showcase 10 with the
temperature detectors 41 and to control the air flow rate of the
air blower 30 according to the detected temperature as shown in
FIG. 13. Similarly, in an open showcase having no built-in freezing
machine as well, temperature detectors 41 may be disposed in the
vicinities of the openings in the front and rear faces of the lower
showcase 10 for use in controlling the air blower 33 as shown in
FIG. 14. It is also conceivable to dispose a damper within the duct
32, or provide a plurality of air blowers facing forward and
backward and to separately control the forward and backward air
flow rates.
[0064] Another conceivable arrangement is to dispose air velocity
detectors 42 in the vicinities of the lower showcase 10 as shown in
FIG. 15 and FIG. 16 to detect the velocities of air flowing out of
the openings in the lower showcase 10 and control the air blower 30
or 33 on that basis. In this case, known sensors such as hot-wire
anemometers can be used as the air velocity detectors 42.
[0065] Further, though not shown, temperature detectors 41 and air
velocity detectors 42 may be disposed in the vicinities of the
lower showcase 10 to detect the temperatures and flow velocities of
air flowing out of the openings in the lower showcase 10 and to
control and the air blowers 30 or 33 on that basis.
[0066] The preferred embodiments described in this specification
are only for the illustrative purpose but not intended to limit the
scope. The scope of the present invention is stated in the appended
claims, and all the modifications that can be covered by the
meaning of the claims are included in the invention.
* * * * *