JPH0367978A - Low temperature container - Google Patents

Abstract

PURPOSE:To make smooth water flow for prevention of freezing as well as improve cooling efficiency by connecting a blow-off outlet of a fan apparatus with a fan duct opening toward lower and upper and lower container boxes, and opening the other end of a cold air feedback duct, whose one end opens toward a lower part of the upper container box, toward the upper part of drain pan. CONSTITUTION:Cold air blasting from a cooler 21 into an upper container box 2 is achieved by incorporation of cold air by an fan apparatus 23 to a lower fan duct 27 and an upper fan duct 41 and by sucking of a back surface part of the upper fan duct 41 by a fan apparatus 44. Cold air blown off from a blow-off outlet 43, and allowed to flow down and accumulated on the lower portion of an upper container box 2 is guided toward an upper feedback duct 42. Due condensed on the inner surface of the upper container box 2 and allowed to flow down or water spilled out from contained articles in the box 2 is accumulated on the bottom surface of the box 2 and allowed to flow from a cold air guide passage 45 to the upper feedback duct 42, and further allowed to flow down from a lower feedback duct 28 to a drain pan 26. The water accumulated on the due receiver dish 26 is discharged to an evaporation dish 32 through a discharge pipe 33. The cold airs flowing through the upper and lower feedback ducts 42, 28 smoothly flow and are discharged without being frozen because it is one flowing through the interior of the upper container box 2 and is at relatively high temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a low-temperature storage cabinet that cools the interior of the cabinet by sending cold air thereinto.

(B) Prior Art As a technology prior to the present invention, there is a forced convection refrigerator (low temperature storage) described in Japanese Utility Model Application Publication No. 79662/1983.

Refrigerators form a water reservoir for storing defrosting water in the middle of a ventilation duct that sends cold air to the refrigerator compartment, and use the ventilation duct as a drainage channel for the defrosting water. Although water generated inside the refrigerator (defrosting water, spilled water, liquid, etc.) is drained away through the ventilation duct, using the ventilation duct exposes the water to colder air at a lower temperature. , it may freeze and obstruct ventilation and drainage.

(c) Problems to be Solved by the Invention The technical object of the present invention is to provide a low-temperature storage that allows water to be drained smoothly without forming a drainage-only passage.

(d) Means for Solving the Problems The present invention comprises a lower storage box body in which a cooler is arranged, and an upper storage box body into which air cooled by the cooler of the lower storage box body is sent through a ventilation duct. In the low-temperature storage facility equipped with a refrigerator, a cooler is installed in the 'FY section inside the lower storage box, a dew pan is installed below the lower suction side of the cooler, and an air blower is installed above the cooler. The outlet of the air blower opens into the lower storage box body and connects to the ventilation duct which opens into the upper storage box body, and the other end of the cold air return duct, which opens at the bottom of the upper storage box body, connects the other end to the top of the dew pan. The problem is solved by the first means of opening the door.

The present invention also provides a lower storage box body and an upper storage box body formed of a heat-insulating box body and each having a door body, a cooler disposed at the back of the lower storage box body, and a lower suction side of the cooler. a dew pan disposed below the cooler; a blower disposed above the cooler; a blower duct having one end connected to the outlet of the blower and the other end opening at the top of the upper storage box; A second means for forming a low-temperature storage with a cold air return duct having one end opened at the bottom of the upper storage box body and the other end opened between the cooler suction side of the lower storage box body and the dew pan. It is something that solves problems.

In the second means, the technical scope includes both the bottom of the tank where cold air is blown out into the lower storage box by the blower, and the bottom of the tank where the cold air is not blown out. At the bottom of the tank where cold air does not blow out into the lower storage box, the inside of the lower storage box is indirectly cooled by a cooler. At the bottom of the tank where the cooler and the inside of the lower storage box are separated by a heat insulating partition plate, the lower storage box becomes a normal temperature storage box.

(E) Function According to the present invention, the water inside the upper storage box can be drained out of the box through the cold air return duct, and the water is further drained by being received by the defrosting water condenser tray of the cooler.

(f) Example A description will be given based on the illustrated implementation structure embodying the groove bottom of the present invention.

The figures illustrate the present invention, and FIG. 2 is a front view of the storage 1.

The storage 1 is formed by an upper storage box body 2 and a lower storage box body 3. A pair of door bodies 4 and 5 which rotate to open and close in opposite directions are attached to the front opening of the upper and lower storage box bodies 2.3.

FIG. 3 is a front view of the storage 1 with the door body 4 open and the right door body 5 open. In FIG. 3, the internal structure is schematically indicated by broken lines. The upper and lower storage box bodies 2.3 include a front-opening upper and lower insulating box body 6.7 made of an outer box, an inner box, and an insulating material filled with foam between the inner and outer boxes, and upper, lower, left and right walls of the upper and lower insulating box bodies 6.7. and upper and lower decorative frames 8.9 that cover the front edge.

The outer box and inner box of the upper and lower insulation boxes 6.7 are formed of synthetic resin plates, metal plates, or the like. The upper and lower decorative frames 8.9 are made of wooden veneer or plywood. Push the upper insulating box 6 through the rear opening of the upper decorative frame board 8, and fit the front edge of the upper insulating box 6 into the front flange 10 of the decorative frame board 8 in a sealed state, preventing it from being pulled out to the rear. This is done using an L-shaped fitting 11 as shown in FIGS. 11 and 12. The lower insulation box 7 is inserted through the rear opening of the lower decorative frame board 9, and the front edge is sealed and fixed at a predetermined position. The fixing structure is a well-known structure.

As shown in the exploded sectional view of FIG. 6, the storage 1 can be separated into an upper storage box 2 and a lower storage box 3, which are stacked together using a connecting body (not shown) and then joined and integrated. Once integrated, do not separate them carelessly unless you use a jig to remove the connecting body. By forming the upper and lower storage boxes 2.3 separately, the volume during transportation can be reduced, and the weight of each unit during installation can be reduced, so that installation work can be carried out smoothly.

A cooler 21 is disposed on the back surface of the lower insulation box 7 of the lower storage box 3, and a suction space 22 serving as a suction port is provided below the cooler 21.
is formed. A blower device 23 is disposed above the cooler 21. The blower device 23 is formed with an air outlet 24 for blowing out cold air into the lower insulation box 7 and an air outlet 25 to the upper storage box 2. A dew pan 26 is disposed below the cooler 21 and below the suction space 22. The lower heat insulating box 7 has a lower air duct 27 connected to the air outlet 25 and a lower return duct 28 communicating with the suction space 22. The lower air duct 27 is formed behind the air blower 23. Cooler 2
1 is placed on the right side of the lower insulation box 7, and the return duct 2
8 is formed at the center of the dorsal inner surface of the lower heat insulating box body 7.

A refrigerant compressor 29, a condenser 30, and a cooling blower 31 are installed in the space below the lower insulation box 7 of the lower storage box 3 and the lower decorative frame 9.
and an evaporating dish 32.

The dew pan 26 and the evaporation pan 32 are communicated through a drain pipe 33. A condenser 30 is arranged in the front lower part of the lower storage box body 3,
A ventilation hole 34 is formed.

An upper ventilation duct 41 is formed on the back surface of the upper insulation box 6 of the upper storage box 2. An upper return duct 42 is formed on the rear lower inner surface of the upper insulation box 6 of the upper storage box 2. The upper air duct 41 and the upper return duct 42 are connected to the lower air duct 27 and the lower return duct 28 of the lower storage box body 3 to form an air duct and a cold air return duct. Upper ventilation duct 41
As shown by the broken line in Fig. 3, a bending formation is formed in the middle. By forming the upper ventilation duct 41 in a bent manner, the upper ventilation duct 41 is positioned at the center of the upper insulation box 6.

FIG. 1 is a right side view taken longitudinally through the center of the storage, and the position of the cooler 21 is indicated by a broken line. FIG. 4 shows a cooler 21 and an air outlet 24 on the right side of the storage 1.
Right side view taken vertically, Figure 5 shows the upper ventilation duct 41
FIG. 6 is an exploded right side view of the upper storage box body 2 and the lower storage box body 3 separated from each other in the cross-sectional state of FIG. 5. FIG. 7 is a plan view of the lower part of the upper storage box body 2 of the storage shed 1, and FIG. 8 is a plan view of the upper storage box body 2 of the storage shed 1.
FIG. 9 is a plan view taken across the top wall of the upper insulation box 6 that constitutes the upper storage box 2 of the storage 1. FIG. Figure 10 is a plan view taken across the center of the upper storage box body 2 with the door body 4 removed from the storage cabinet 1.A virtual person M and line of sight I (-dotted chain line) are shown in the drawing to explain the display state. It shows. FIG. 11 is an enlarged cross-sectional view of the right side of the upper storage box body 2 with the door body 4 closed, and FIG. 12 is an enlarged cross-sectional view of the right side of the upper storage box body 2 with the door body 4 open. be. 16th
The figure is an enlarged right side view of the rear upper part of the upper storage box body 2. Figure 17 shows the upper storage box body 2 and the lower storage box body 3 in the storage shed 1.
FIG. 2 is an enlarged right side view of the connecting portion taken longitudinally at the center.

The upper air duct 41 is formed to extend over the inner surface of the ceiling wall of the upper heat insulating box 6, and the air outlet 43 is disposed at the front of the inner surface of the ceiling wall. A blower device 44 is formed at a corner between the inner surface of the ceiling wall and the inner surface of the back of the upper blower duct 41. The blowing of cold air from the cooling @ 21 into the upper storage box body 2 involves pushing (blowing) cold air into the lower air duct 27 and the upper air duct 41 by the air blower 23, and the blowing of the cold air into the upper air duct 41 by the air blower 44. This is done by sucking up the back part. When the distance between the lower ventilation duct 27 and the upper ventilation duct 41 is long and the ventilation resistance is large, cold air can be efficiently blown to a high place using the small ventilation device 23.44. Since the upper air duct 41 is bent in the middle, the air blowing resistance increases, but the air blowing resistance due to the gravity of the cold air with increased specific gravity can be reduced, and the air blowing devices 23 and 44 can be stopped to prevent the backflow of cold air. It is preventable. Air blower 23.
44 is stopped when the temperature sensor detects that the internal temperature of the upper storage box body 2 and the lower storage box body 3 has reached a predetermined value.
This is when the cooler 21 is frosted and the defrosting operation is started.

The upper return duct 42 opens at the lower center corner of the rear surface of the upper heat insulating box 6. A cold air guide passage 45 communicating with the upper return duct 42 is formed at the rear of the inner bottom surface of the double-insulated box 6. The cold air guide passage 45 extends to both sides of the rear part of the inner bottom surface, and also extends to the front of the center part. In this embodiment, the cold air guide passage 45 is formed by a recess.

The cold air that is blown out from the air outlet 43, flows down, and accumulates in the lower part of the upper storage box body 2 is efficiently guided to the upper return duct 42.

Dew that condenses and flows down the inner surface of the upper storage box 2 or water liquid spilled from the items stored in the upper storage box 2 accumulates on the bottom of the upper storage box 2 and flows from the cold air guide passage 45 to the upper return duct 42. It flows down from the lower return duct 28 to the dew pan 26. The water accumulated in the dew pan 26 is drained to the evaporation pan 32 through a drain pipe 33. The cold air flowing through the upper return duct 42 and the lower return duct 28 is cold air that has flowed inside the upper storage box body 2 and has a relatively high temperature, so the water does not freeze and the water flows in the same direction as the cold air. Because it flows, it flows smoothly and drains water. By using the upper and lower return ducts 42.28 as drainage passages, no special structure for drainage is required.

A plurality of shelves 5 and 52 are arranged in the upper storage box body 2. In this embodiment, the shelves 51 and 52 are formed in four stages. The lowermost shelf 52 is formed of a metal plate and is connected to the upper insulation box 6.
A cold air circulation interval is formed from the bottom of the 15
Reference numeral 2 corresponds to the inner lower plate of the upper storage box body 2, and if the mounting structure is designed to be removable, inspection, repair, and cleaning can be carried out smoothly. The attachment/detachment structure may be a locking structure that does not use a jig, or may be a structure in which attachment/detachment is performed using a jig such as a simple screwdriver.

The other three shelves 51 are made of impact-resistant glass and are arranged so as to divide the space above the shelf 52 into four. Shelf 51
The mounting position of the shelves 51 is such that the distance between the shelves 51 can be changed depending on the usability of the user. Supports 53 are formed on both sides of the dorsal inner surface of the upper heat insulating box body 6 of the upper storage body 2. Pillar 5
3 is a hollow body made of metal. The shape of the hollow body may be a cylinder, a frame with a U-shaped cross section, or the like, as long as the inside thereof forms a cold air circulation duct. A plurality of locking holes 54 which also serve as ventilation holes are formed in the vertical direction in the support column 53. The locking hole 54 is formed, for example, in a vertically elongated rectangular shape, and is formed in the front wall of the support column 53. Although an engaging body that is directly locked to the locking hole 54 of the support column 53 may be formed at the rear end of the shelf 51, in this embodiment, the separate shelf support supports the body 55 to the support column 5.
3 and indirectly connect the shelf 51 to the support post 5.
It is supported by 3. The shelf 51 has both side parts and the shelf support is the body 55.
The shelf 51 is placed and supported, and both side edges of the shelf 51 are opposed to the positioning pieces 56 to prevent the shelf 51 from rubbing sideways. The positional relationship between the shelf 51, the shelf support body 55, and the positioning piece 56 is clearly shown in FIGS. 11 and 12.

The lower end of the support column 53 is open and communicates with the cold air guide passage 45 with which the main return duct 42 communicates. By communicating the pillar 53 with the cold air guide passage, the cold air flows through the pillar 53.
The cold air is sucked in through the locking hole 54 and flows downward inside the support column 53 and into the cold air guide passage 45. Since the cold air is sucked in through the locking hole 54 of the support column 53, the pressure in the space between the shelves 51, 52 is reduced, and the cold air blown out from the outlet 43 is sucked into the space between the shelves 51, 52. Therefore, the shelf 51,
．． In this implementation structure where 52 has no air permeability, the air outlet 43
This prevents the cold air blown out from flowing down along the door body 4 and directly from the cold air guide passage 45 into the main return duct 42, allowing the cold air to circulate efficiently within the upper storage body 2. . By using the support column 53 as a cold air suction duct, there is no need to form a separate duct, and the structure is simplified.

A royal air duct 41 is formed on the inner surface of the ceiling wall of the upper heat insulating box body 6 of the upper storage body 2 so as to expand from the back toward the front air outlet 43. Royal road style duct 4 that has expanded
1, lighting devices 61 are formed at two places on the left and right in the central part of the front and back of the ceiling wall. The lighting device 61 consists of a bottomed cylindrical frame 62 with an open bottom, a socket body 163 attached to the back wall of the cylindrical frame 62, and a lamp body 64 connected and supported by the socket body 63. The cylindrical frame 62 passes through the upper air duct 41 and is attached to four parts formed on the ceiling wall of the upper heat insulating box 6, as shown in FIG. The lamp body 64 can be easily replaced since the lower surface of the cylindrical frame body 62 is open. A ventilation hole 65 is formed in a portion of the cylindrical frame body 62 on the side of the blower 44 located inside the upper blower duct 41. Air vent 6
5, the cold air blown into the cylindrical frame 62 is transferred to the cylindrical frame 6.
A change plate body 66 is formed to guide the rear wall of No. 2.

The cold air flowing through the upper ventilation duct 41 is blown out from the air outlet 43 into the upper storage body 2, and is also blown into the cylindrical frame 62 from the ventilation hole 65 of the cylindrical frame 62 of the lighting device 61, and is The air is blown out into the upper housing body 2 from the lower opening of the body 62. The lighting device 61 is cooled by cold air flowing around the cylindrical frame 62 and flowing inside the cylindrical frame 62 .

Particularly, when an incandescent light bulb is used as the lamp body 64, the lamp body 64 can be cooled to extend its life, and the temperature rise in the upper storage part body 2 due to the heat of the lamp body 64 can be suppressed.

2. Reflective plates 71 and 72 are disposed on both side walls and the inner surface of the back wall of the upper insulation box 6 of the upper storage unit body 2. The reflecting plate 71 is arranged between the columns 53 on the inner surface of the back wall. The reflecting plates 72 disposed on the inner surfaces of both side walls are formed so that the angle can be changed by moving the rear side.

By surrounding the shelves 51.52 with the reflective plates 71.72, the articles placed on the shelves 51.52 are reflected on the reflective plates 71.72,
The exhibition effect can be improved. The appearance is due to the effect that multiple objects appear, and the reflection plate 7L as the person M moves.
The state reflected in 72 changes. When viewed from the direction shown in FIG. 10, the article B appears to be countless because it is repeatedly reflected by the reflecting plate 72. Furthermore, since the lighting devices 61 are also reflected on the reflecting plates 71 and 72, the number of lighting devices becomes plural, and the decorative lighting effect is improved.

The door body 5 of the lower storage box body 3 is formed of a heat insulating board. The front surface of the door body 5 is made of a material, shape and color that match the decorative frame body 9.

The door body 4 of the upper storage body 2 has two transparent glass plates 8 on a door frame 81.
2 are fitted to form a heat insulating space to form a translucent door body. An electric heater 83 for preventing dew condensation is disposed within the door frame 81 of the door body 4. The door frame 81 and the transparent glass plate 82 are hermetically connected. In this embodiment structure, in order to improve the heat insulation effect of the door body 4, a translucent heat ray reflective film 84 is stretched between the transparent glass plates 82.

Both the upper and lower end portions of the door body 4 on the pivot side are held and rotatably supported at two locations, a first guide portion 85 and a second guide portion 86. The pivot side end of the door body 4 is guided and slidably supported in the front-rear direction along the side inner surface of the upper storage box body 2 at the first guide portion 85 . A portion slightly inside the pivot side end of the door body 4 is guided and slidably supported in the left-right direction along the opening of the upper storage box body 2 at the second guide portion 86 . A support shaft 87.88 is provided protruding from the portion of the door body 4 supported by the first and second guide portions 85.86. A reinforcing member 89 is attached to the door frame 81 at the protruding portion of the support shafts 87 and 88. The support shafts 87, 88 are rotatably attached to the reinforcing member 89. The support shafts 87 and 88 are made of a conductive member and are connected to one end of the electric heater 83 with a screw. Reinforcement member 8
9 is made of an insulator. Electric heater 83 and support shaft 8
The structure of the connecting portion with 8 is shown in the sectional views of FIGS. 13 and 4.

In this structure, the first and second guide portions 85 and 86 are formed by grooves formed in the upper heat insulating box 6. First and second guide section 85.
86 are formed in a substantially orthogonal positional relationship as shown in FIG. The inside of the first and second guide parts 85 and 86 is formed of an insulating plate, and a support collar part 90 is formed in the opening. The first and second guide parts 85 and 86 accommodate sliding bodies 92 and 93 having a pair of front and rear rolling bodies 91 that roll and move on the collar part 90. A support shaft 87 for the door body 4 is attached to the front part of the sliding body 92 of the first guide part 85. A support shaft 88 is attached to the pivot side of the sliding body 93 of the second guide portion 86 .

When the door body 4 is in the closed state, its pivot side portion is in the position shown in FIG. 11. In this state, when the movable side of the door body 4 is pulled forward to open, a force that tries to rotate around the support shaft 88 is first applied, and the support shaft 87 is moved along the first guide portion 85. This results in a force acting to move it inward. When a force trying to move the support shaft 87 along the first guide section 85 acts, a force that tries to move the support shaft 88 along the second guide section 86 acts in turn. The force acting on the support shafts 87 and 85 to open the door body 4 causes the support shafts 87 to move inward along the first guide portion 85, and the support shafts 88 to move toward the second guide portion. This acts as a force to move the door body 4 outward along the section 86, and guides the door body 4 to open it. By this operation, the pivot side of the door body 4 is pushed into position along the side inner surface of the upper storage box body 2 in the open state as shown in FIG. By inserting the pivot side of the door body 4 into the upper storage box body 2, the amount of protrusion of the door body 4 in the open state is reduced. Since the door body 4 is opened while being inserted into the upper storage box body 2 even during opening, the space of the door body 4 for opening can be reduced. The opening/closing operation of the door body 4 can be performed in the same manner as the opening/closing operation of a door body pivoted at one point, and the pivot side portion can be inserted without requiring a pushing operation of the door body 4.

In this embodiment structure, since the electric heater 83 is attached to the door body 4, it is necessary to supply power. A sliding contact 94.95 connected to the support shaft 87.88 is formed at a portion of the sliding body 92.93 to which the support shaft 87.88 is attached. Sliding contact 94.9
5 is biased by a spring body and protrudes from the upper surface of the sliding body 92.93. Fixed contacts 96.97 are formed on the back surface of the first and second guide portions to contact the sliding contacts 94.95. are doing.

A power supply circuit to the electric heater is formed by the sliding contacts 94.95 coming into contact with the fixed contacts 96.97. The fixed contacts 96 and 97 are connected to the sliding contacts 94 and 9 when the door body 4 is closed.
5 is formed only at the position where it contacts. Followed, door body 4
When is open, power is not supplied to the electric heater 83,
Power is supplied only when the door body 4 is closed. Since the sliding contact 94.95 and the fixed contact 96.97 serve as the switch for power supply/non-supply, the number of parts is reduced and the structure is simplified.

When the door body 4 is closed, the sealing structure in the upper storage box body 2 is performed by the seal bodies 98 and 99. The pivot side of the door body 4 is sealed by attaching a seal body 98 to the front flange 10 of the upper decorative frame body 8 and bringing the front side of the door body 4 on the pivot side into contact with the seal body 98. A seal body 9 is provided at the upper and lower ends and the open end of the
9 is attached, and the open end portions of the door bodies 4 are brought into contact with each other and against the inner surface of the upper storage box body 2.

The present invention is not limited to the above-described implementation structure, but can be implemented with modifications within the scope of well-known techniques.

For example, a blower duct and a cold air return duct are formed integrally with a heat insulating box and a groove is formed, but it is also possible to form a completely separate member and incorporate it into the heat insulating box. good. In order to smoothly guide water to the upper return duct at the bottom surface of the upper storage box body, the cold air guide passage may be formed into a slope that becomes lower toward the upper return duct.

(g) Effects of the invention The present invention provides the following effects by using the cold air return duct as a water drainage channel.
The direction of the flow of water and the flow of cold air is the same, so the flow is smooth, the water can be prevented from freezing, and the cooler is not splashed with water, allowing efficient cooling.

[Brief explanation of drawings]

The figures show one implementation structure of the present invention, in which Fig. 1 is a right side view of the center vertical section, Fig. 2 is a front view of the storage, Fig. 3 is a front view of the storage with the door open, and Fig. 4. Figure 5 is a right side view taken longitudinally of the different parts from Figure 1, Figure 6 is an exploded sectional view of Figure 5, Figure 7 is a cross-sectional plan view, Figure 8 is a cross-sectional bottom view, and Figure 9 is a cross-sectional view.
The figure is a cross-sectional plan view of the ceiling wall of the upper insulation box, Fig. 10 is a cross-sectional plan view with the door removed, Fig. 11 is an enlarged cross-sectional plan view of the main part with the door closed, and Fig. 12 is the door open. 13 and 14 are longitudinal cross-sectional views taken in different directions of the door body support part. FIG. 15 is a cross-sectional plane view of the pivot side part in the closed state of the door body, and Figure 16 17 is a vertical right side view of the upper rear portion of the upper storage box, and FIG. 17 is a right side view of the connection between the upper storage box and the lower storage box. 1...Storage car, 2...Upper storage box, 3.
...Lower storage box body, 4...Door body, 21...
Cooler, 22... Suction space, 23... Air blower,
24...Air outlet, 26...Dew pan, 27...
...Lower air duct, 28...Lower return duct, 4
1...Royal wind duct, 42...Upper return duct, 43...Air outlet, 44...Blower device, 4
5...Cold air guide passage, 51.52...Shelf,
53... Support column, 54... Locking hole, 55...
・The shelf support is the body, 61...Lighting device, 62...
Cylindrical frame body, 64...Lamp body, 65...Vent hole, 71.72...Reflector plate, 81...Door frame, 82...Transparent glass Plate, 83... Electric heater, 85... First guide part, 86... Second guide part, 87.88... Support shaft, 92.93...9 ・・Sliding body, 94.95... 7...Fixed contact Sliding contact, 96.9 0

Claims (1)

[Scope of Claims] 1. In a low-temperature storage cabinet equipped with a lower storage box body in which a cooler is arranged and an upper storage box body into which air cooled by the cooler of the lower storage box body is sent through a ventilation duct. , a cooler is installed at the back of the lower storage box, a dew pan is installed below the lower suction side of the cooler, a blower is installed above the cooler, and the blower outlet is located at the bottom. A low-temperature storage cabinet that is connected to a ventilation duct that opens into the storage box body and the upper storage box body, and has one end opened at the bottom of the upper storage box body and a cold air return duct whose other end is opened at the top of the dew pan. . 2. A lower storage box body and an upper storage box body formed of a heat-insulating box body with a door formed thereon, a cooler placed on the back inside the lower storage box body, and a cooler placed below the lower suction side of the cooler. The dew saucer set up and
A blower device installed above the cooler, a blower duct with one end connected to the air outlet of the blower device and the other end opened at the top of the upper storage box, and one end opened at the bottom of the upper storage box. and a cold air return duct whose other end opens between the cooler suction side of the lower storage box body and the dew pan.