JP2001221553A - Cold insulation cabinet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold insulation cabinet capable of cold insulating food and drink or the like by lowering an interior of an inner container to a cryostatic temperature. SOLUTION: The cold insulation cabinet comprises a box-shaped body 1 having an opening above, an inner container 8 arranged in the body 1, a cover 2 for opening/closing the opening of the body 1, and a Stirling refrigerator 14 for generating a cold by a reverse Stirling cycle. In this case, the cold heat is transferred to the container 8 to cold insulate the food and drink or the like contained in the container 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator for storing food and drinks in a refrigerator and, more particularly, to a small refrigerator which can be taken out and used outdoors.

[0002]

2. Description of the Related Art There are various types of conventional electronic cool refrigerators, and there is a refrigerator using a Peltier element for cooling the refrigerator. As shown in FIGS. 13 and 14, for example, the electronic cool box has a substantially rectangular parallelepiped appearance.
A space 101 for keeping food cool is formed therein, and one Peltier element 103 is used as a cooling source.
That is, this electronic cool box is filled with a main case 104, an inner case 105 formed of an inner case 105 and a cooling wall 106 made of metal such as aluminum, and a space between the main case 104 and the inner container 107. Cooling unit 11 comprising heat insulating material 108, Peltier element 103, spacer 109, and radiating fins 110 and fixed to inner container 107 with screws or the like.
1, a cooling fan 112, a side cover 113 covering the cooling unit 111 and the cooling fan 112, and a lid 102 filled with a heat insulating material 114 therein.

An example of a general method of using the conventional electronic cool box will be described. Many of these electronic cool boxes have a power consumption of around 48 W, and there is no problem when the electric cool box is loaded on a vehicle and supplied with power from a battery of the vehicle. However, when used outdoors such as camping, an outdoor portable power supply is required. For example, when used at a voltage of 12 V, the electric cooler consumes about 48 W, so a current of 4 A is required. Therefore, a portable power supply having a capacity of 40 Ah or more was required for use for 10 hours or more. Such large-capacity portable power supplies are difficult to obtain for users and, if available, were very expensive.
The units used here were W for watts, V for volts, A for ampere, and h for hours.

[0004]

The above-mentioned conventional electronic cool box is generally widely used, but consumes 48 power.
Since it was around W, a large-capacity power supply for supplying the power was necessary, but the power supply was difficult for users to obtain and very expensive. Therefore, the conventional electronic cool box requires a large-capacity power supply such as a commercial power supply or an automobile battery, and is inconvenient in power supply.

Further, in the conventional electronic cool box, the cooling temperature of the Peltier element as a cooling source is also at least around 0 ° C., and the cooling capacity is comparable to that of the freezer (inside temperature −18).
° C) could not be obtained.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to provide a cool box that can keep food and drink and the like cold by keeping the inside of an inner container at an extremely low temperature. Another object of the present invention is to provide an energy-saving cool box that can be used continuously for a long time even in a place where there is no power supply equipment such as outdoors.

[0007]

In order to achieve the above object, a refrigerator according to the present invention comprises a box-shaped main body case having an opening, an inner container arranged inside the main body case,
A lid that opens and closes the opening of the main body case, and a Stirling refrigerator that generates cold heat by a reverse Stirling cycle, and transmits the cold heat to the inner container to keep foods and the like stored in the inner container cool. It is characterized by doing so.

[0008] According to this, the food and the like accommodated in the inner container can be kept cool for a long time by the extremely low temperature heat generated by driving the Stirling refrigerator.

The inner container has a shape in which side walls are erected on four sides of a substantially rectangular bottom surface, and the Stirling refrigerator is arranged in the reclining direction along the short side wall. The space outside the side can be used effectively.

On the other hand, the inner container has a shape in which side walls are erected on four sides of a substantially rectangular bottom surface, and the Stirling refrigerator is arranged in a standing direction along a short side wall. The space outside the vessel can be more effectively used.

If the inner container is directly cooled by the cold heat of the Stirling refrigerator, an appropriate cooling effect can be obtained with a small number of components.

On the other hand, if a refrigerant circulation line is formed along the side wall of the inner container, and the refrigerant cooled by the cold heat of the Stirling refrigerator is circulated in the refrigerant circulation line, Cold heat is uniformly transported to the entire periphery of the inner container via the refrigerant flowing through the refrigerant circulation line.

When a solar cell is used as a drive source of the Stirling refrigerator, a cool box can be used even in a place where there is no power supply equipment, such as outdoors.

In this case, if the solar cell is mounted on the upper surface of the lid, the solar cell can be arranged in a small space.

If the solar cell is arranged on the upper surface of the lid so that the angle can be changed according to the direction of solar radiation, it is easy to secure the amount of solar radiation necessary for solar power generation.

Further, when a solar cell is also attached to the outer periphery of the main body case, the effective power generation area of the solar cell increases,
It is easier to secure the amount of solar radiation required for solar power generation.

Furthermore, if the Stirling refrigerator is provided with a secondary battery and can be driven by the electric power charged in the secondary battery, the cool box can be used continuously even in a place where there is no power supply equipment such as outdoors. .

If the Stirling refrigerator is driven by an electric power generated by the solar cell or an electric power charged to the secondary battery via an inverter circuit, the solar power generation can be performed during the day and at night. By driving the Stirling refrigerator using the charged secondary battery, the refrigerator can be used continuously for a long time even in places where there is no power supply equipment such as outdoors.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <First Embodiment> A first embodiment of the present invention
An embodiment will be described with reference to the drawings. FIG.
It is an external appearance perspective view of the cool box which concerns on this embodiment, consists of the main body 1 and the cover 2, and is formed in the substantially rectangular parallelepiped shape. In addition, a slit 10 having an opening is provided in a lower right portion of the front surface of the main body 1. In addition, 11 is a power plug connected to an external power source, and 12 is a cord connecting the main body 1 and the power plug 11.

FIG. 2 is a side sectional view of the cool box.
As shown in FIG. 2, the lid 2 is filled with a heat insulating material 3 and is attached rotatably about the main body 1 and hinge pins 4 (FIG. 1). Reference numeral 5 denotes an outer case made of a synthetic resin, which has a box shape having a substantially rectangular bottom wall and an open upper surface, and a hook 5a (FIG. 1) for fixing the lid 2 is formed on the outer surface. Reference numeral 6 denotes an inner case made of synthetic resin, which has a box shape having a substantially rectangular bottom wall and an upper surface opened, and a fixing portion 6a for fixing an upper end of the outer case 5 is formed on a peripheral edge of the upper end. Reference numeral 7 denotes a cooling wall 7 which is a metal such as aluminum and is closely disposed in the inner case 6 without any gap, and has a U-shaped cross section as shown in FIG.
Its upper end is engaged with and fixed to the engaging portion 6b. By the inner case 6 and the cooling wall 7, the inner container 8 referred to in the present invention is formed.
Is formed. Reference numeral 9 denotes a heat insulating material, which is filled in a portion surrounded by the outer case 5 and the inner container 8.

FIG. 3 is a horizontal sectional view of the cool box.
A machine room 13 is formed on the right side of the main body 1, and a free piston type Stirling refrigerator 14 described later is provided in the machine room 13 in the reclining direction. 6c is
The arm portion is formed integrally with the inner case 6 or made of the same material as the inner case 6. As shown, the cold head 26 of the Stirling refrigerator 14 is in contact with one end of the arm 6c. Further, the cooling fan 1 is provided in the machine room 13.
5 and an inverter circuit 16 are provided. Incidentally, 17
Is a temperature sensor for detecting the temperature inside the inner container 8.

FIG. 4 is a sectional view of a free piston type Stirling refrigerator suitably used in the present embodiment. Stirling refrigerators are known as a type of small refrigerator that generates cryogenic cold through a thermodynamic cycle known as a reverse Stirling cycle. The operation will be described with reference to FIG. The piston 18 is driven by a linear motor 19 and moves sinusoidally by a spring 20 for resonance. The working gas in the compression space 21 makes a sinusoidal motion due to the movement of the piston 18. The compressed working gas is
The compression heat is released by the heat radiating portion 22, and is precooled by the regenerator 24 in the displacer 23 and enters the expansion space 25.

The pressure of the working gas in the expansion space 25 changes sinusoidally with a certain phase difference from the pressure in the compression space 21.
That is, the displacer 23 slides with respect to the piston 18 while maintaining a certain phase difference. After the working gas flows into the expansion space 25 and expands, the cold head 26
Deprives the heat from outside through. The expanded working gas passes through the regenerator 24 and returns to the compression space 18. At this time, the working gas is preheated by recovering the heat of the regenerator 24. By repeating the above-described series of cycles, it is possible to obtain cryogenic heat at the cold head unit 26.

As shown in FIG. 3, the cold head 26 of the Stirling refrigerator 14
c, the cold generated in the cold head 26 by the drive of the Stirling refrigerator 14 is transferred to the arm 6c.
Directly from the inner case 6 made of metal such as aluminum,
The space inside the inner container 8 is cooled. Therefore, the food and the like accommodated in the inner container 8 can be efficiently kept cool with a small number of components.

On the other hand, when the Stirling refrigerator 14 is driven, the radiator 22 from which heat is released becomes extremely hot.
In order to improve the cooling performance of the Stirling refrigerator 14, it is necessary to cool the radiator 22. Therefore, in the present embodiment, the heat radiation unit 22 is
And the air that has taken heat from the heat radiating section 22 is allowed to escape from the slit 10 to the outside of the main body 1 positively.

The inverter circuit 16 that determines the driving method of the refrigerator 14 does not change the frequency as in the case of the control by a general inverter, but uses the resonance spring 20 (FIG. 4) according to the present invention. In consideration of the characteristics of the Stirling refrigerator 14, a method of changing the applied voltage at a constant frequency (so-called PAM) is employed.

Next, an operation example of the Stirling refrigerator according to the present embodiment will be described. When the power is turned on by plugging the power plug 11 into an external power source, the temperature inside the inner container 8 is detected by the temperature sensor 17 provided on the inner wall surface of the inner case 6. When the temperature inside the inner container 8 is lower than the predetermined set temperature, the voltage applied to the Stirling refrigerator 14 is reduced, and conversely, when the temperature inside the inner container 8 is higher than the set temperature, the Stirling The voltage applied to the refrigerator 14 is increased to drive the refrigerator 14 at a high output. Thereby, since the temperature in the inner container 8 can be maintained within a certain range, the influence on the food and drink and the like due to the temperature change can be prevented.

<Second Embodiment> A second embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a front sectional view of the cool box according to the present embodiment. In FIG. 5, the same members as those of the cool box according to the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals, and detailed description thereof will be omitted.

A characteristic feature of this embodiment is that, as shown in FIG. 5, a Stirling refrigerator 14 (see FIG. 4) is arranged in a standing direction in a machine room 13 formed on the right side of the main body 1. It is. Thereby, the dead space in the machine room 13 of the cool box main body 1 is reduced, and the space of the machine room 13 can be used effectively. In addition, since the use form of the cool box conforms to the first embodiment, the description thereof is omitted here.

<Third Embodiment> A third embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a horizontal sectional view of the cool box according to the present embodiment. In FIG. 6, the same members as those of the cool box according to the first embodiment shown in FIG. 3 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As a characteristic configuration of this embodiment, as shown in FIG. 6, a Stirling refrigerating machine 14 (see FIG. 4) is disposed in a machine room 13 on the right side of the main body 1, and a cold head 26 thereof is mounted. The refrigerant pipe 27 is routed along the outer wall surface of the inner case 6 so as to form a closed circuit, and the refrigerant which is an antifreeze such as brine is circulated in the refrigerant pipe 27 in the middle of the refrigerant pipe 27. Is provided.

As a result, the cold head 26 of the Stirling refrigerator 14 is
The inner case 6 can be uniformly cooled over a wide area by transporting the cold heat of the cold head 2 of the Stirling refrigerator 14.
The internal space of the inner container 8 can be made wider than in the first and second embodiments due to the contact between the inner case 6 and the inner case 6. The arrangement direction of the Stirling refrigerator 14 is not limited to the reclining direction as shown in FIG. 6, but may be the standing direction as in the second embodiment.

<Fourth Embodiment> A fourth embodiment of the present invention will be described with reference to the drawings. FIG. 7 is an external perspective view of the cool box according to the present embodiment. In FIG. 7, the same members as those of the cool box according to the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The Stirling refrigerating machine 14 (FIG. 4) according to the present invention is small in size and high in efficiency (for example, a refrigerating capacity of 30 W or more with an input of 15 W. In this case, the cooling surface temperature is about 0 ° C.). ), So that
It is possible to use solar power generation with relatively low output. Therefore, in this embodiment, as shown in FIG. 7, a solar cell 29 is used as a drive source of the Stirling refrigerator 14 (FIG. 3) in addition to the external power supply. This makes it possible to use the cool box in a place where there is no power supply equipment, such as outdoors, during the daytime.

<Fifth Embodiment> A fifth embodiment of the present invention will be described with reference to the drawings. FIG. 8 is an external perspective view of the cool box according to the present embodiment. 8, the same members as those of the cool box according to the fourth embodiment shown in FIG. 7 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The feature of this embodiment is that the solar cell 29 is fixed to the upper surface of the lid 2 of the cool box as shown in FIG. As a fixing method, for example, a method in which a substantially rectangular concave portion is formed on the upper surface of the lid 2 and the panel of the solar cell 29 is embedded in the concave portion together with a transparent resin can be used. According to this, it is possible to realize an energy-saving cold storage box that is considered compact.

<Sixth Embodiment> A sixth embodiment of the present invention will be described with reference to the drawings. FIG. 9 is an external perspective view of the cool box according to the present embodiment. In FIG. 9, the same members as those of the cool box according to the fifth embodiment shown in FIG. 8 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 9, a characteristic feature of this embodiment is that a solar cell 29 is provided on the upper surface of the lid 2 and the angle of the solar cell 29 can be changed by using a folding angle 30 (D). Direction). According to this, since the angle of the solar cell 29 can be changed according to the direction of solar radiation, the amount of solar radiation incident on the surface of the solar cell 29 can be increased, and solar power generation can be performed efficiently.

<Seventh Embodiment> A seventh embodiment of the present invention will be described with reference to the drawings. FIG. 10 is an external perspective view of the cool box according to the present embodiment. In FIG. 10, the same members as those of the cool box according to the fifth embodiment shown in FIG. 8 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The feature of this embodiment is that the solar cells 29 are arranged not only on the upper surface of the lid 2 but also on the outer peripheral surface of the main body 1 as shown in FIG. According to this, the effective power generation area of the solar cell 29 is increased, so that the solar power generation can be performed efficiently, and an energy-saving cold storage box that is considered in terms of compactness can be realized.

<Eighth Embodiment> An eighth embodiment of the present invention will be described with reference to the drawings. FIG. 11 is a block diagram illustrating a control configuration of the cool box according to the present embodiment,
FIG. 12 is a flowchart of the control method. In the fourth to seventh embodiments, the solar cell 29 (FIGS. 7 to 10) can be used as a drive source of the Stirling refrigerator 14 (FIG. 4). However, in a situation where there is no sunshine, such as at night, solar power cannot be generated, so that an external power source such as an automobile battery must be used. Therefore, in the present embodiment, a device has been devised so that the cool box can be continuously used without relying on the external power supply even in such a situation.

The control method will be described below with reference to FIGS. Now, initial conditions such as the temperature inside the inner container 8 (FIG. 3) are set in advance (step # 10).
In step # 20, the operation switch (not shown) of the cool box is turned ON without using the external power supply 31. Then, the process proceeds to step # 30, and the temperature inside the inner container 8 is detected by the temperature sensor 17. If the temperature in the inner container 8 is higher than the temperature set in step # 10, the process proceeds to step # 4.
At 0, the amount of solar radiation (brightness) detected by the optical sensor 32 provided at an arbitrary position on the outer surface of the cold storage body 1 (FIGS. 7 to 10).
Is higher than the predetermined value, the process proceeds to step # 50, where the control unit 33 outputs the power to the power supply circuit 34 to supply the power from the solar cell 29 to the inverter circuit 16 to drive the Stirling refrigerator 14 (step # 50). # 70)
The relay circuit 35 is switched to the contact A side to charge the surplus power to the secondary battery 36.

On the other hand, if the illuminance is insufficient, step #
60, the relay circuit 35 is switched to the contact B side, so that the power is supplied from the secondary battery 36 to the inverter circuit 16 to drive the Stirling refrigerator 14 (step # 70). Is output to In either case, the cooling fan 15 is simultaneously turned on (step # 80).

In step # 30, the inner container 8
When it is recognized that the temperature inside is lower than the set temperature, the Stirling refrigerator 14 (Step # 90) and the cooling fan 15 (Step # 100) are turned off to save power. Then, the process returns to step # 10, and the above-described series of operations is repeated.

Therefore, according to the present embodiment, even when the solar power generation cannot be performed at night or the like, the external battery can be converted to the external power by using the power charged in the secondary battery by the solar power generation when there is sufficient sunshine. An energy-saving cold storage that can continuously drive the Stirling refrigerator without relying on it can be realized.

[0046]

As described above, according to the present invention, since the internal space of the inner container is cooled by utilizing the cold heat of the Stirling refrigerator, the inner container is cooled as compared with the conventional electronic cool box using the Peltier device. Can keep food and drinks stored at a very low temperature. Therefore, it is possible to prevent adverse effects on foods and drinks due to a temperature change inside the inner container.

Further, since a solar cell is used as a drive source of the Stirling refrigerator, it is possible to use the cool box even in the daytime even in a place where there is no power supply equipment such as outdoors. By storing the surplus power from daytime solar power generation in a secondary battery, the power can be used to drive the Stirling refrigerator at night, so that it can be used for a long time in places without power supply equipment. It is possible to realize an energy-saving cold storage that can be used by using.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a cool box according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of the cool box.

FIG. 3 is a horizontal sectional view of the cool box.

FIG. 4 is a longitudinal sectional view of an example of a free piston type Stirling refrigerator.

FIG. 5 is a front sectional view of a cool box according to a second embodiment of the present invention.

FIG. 6 is a horizontal sectional view of a cool box according to a third embodiment of the present invention.

FIG. 7 is an external perspective view of a cool box according to a fourth embodiment of the present invention.

FIG. 8 is an external perspective view of a cool box according to a fifth embodiment of the present invention.

FIG. 9 is an external perspective view of a cool box according to a sixth embodiment of the present invention.

FIG. 10 is an external perspective view of a cool box according to a seventh embodiment of the present invention.

FIG. 11 is a block diagram showing a control configuration of a cool box according to an eighth embodiment of the present invention.

FIG. 12 is a flowchart of the control method.

FIG. 13 is an external perspective view of a conventional electronic cool box.

FIG. 14 is a front sectional view of the cool box.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Lid 3,9 Heat insulation material 4 Hinge pin 5 Outer case 6 Inner case 7 Cooling wall 8 Inner container 10 Slit 11 Power plug 12 Cord 13 Machine room 14 (Free piston type) Stirling refrigerator 15 Cooling fan 16 Inverter circuit 17 Temperature sensor 18 Piston 19 Linear motor 20 Resonance spring 21 Compression space 22 Heat radiator 23 Displacer 24 Regenerator 25 Expansion space 26 Cold head unit 27 Refrigerant pipeline 28 Pump 29 Solar cell 30 Angle 31 External power supply 32 Optical sensor 33 Control unit 34 Power supply circuit 35 Relay circuit 36 Secondary battery

Claims (11)

[Claims] A box-shaped main body case having an opening;
An inner container arranged inside the main body case, a lid body for opening and closing the opening of the main body case, and a Stirling refrigerator for generating cold heat by a reverse Stirling cycle are provided, and the cold heat is transmitted to the inner container. Wherein the food or the like stored in the inner container is kept cool. 2. The inner container has a shape in which side walls are erected on four sides of a substantially rectangular bottom surface, and the Stirling refrigerator is disposed in a reclining direction along a short side wall. Item 4. The cool box according to Item 1. 3. The inner container has a shape in which side walls are provided upright on four sides of a substantially rectangular bottom surface, and the Stirling refrigerator is arranged in a standing direction along a short side wall. The cool box according to claim 1. 4. The refrigerator according to claim 1, wherein the inner container is directly cooled by cold heat generated by the Stirling refrigerator. 5. A refrigerant circulation line is formed along a side wall of the inner container, and a refrigerant cooled by cold heat of the Stirling refrigerator is circulated in the refrigerant circulation line. The cold storage according to any one of claims 1 to 3. 6. The cool box according to claim 1, wherein a solar cell is used as a drive source of the Stirling refrigerator. 7. The cool box according to claim 6, wherein the solar cell is mounted on an upper surface of the lid. 8. The cool box according to claim 6, wherein the solar cell is disposed on the upper surface of the lid so as to be able to change the angle in accordance with the direction of solar radiation. 9. The cool box according to claim 7, further comprising a solar cell attached to an outer peripheral portion of the main body case. 10. The cool box according to claim 6, further comprising a secondary battery, wherein the Stirling refrigerator can be driven by the electric power charged in the secondary battery. 11. The refrigerator according to claim 10, wherein the Stirling refrigerator is driven by an electric power generated by the solar cell or an electric power charged in a secondary battery via an inverter circuit.