KR101440017B1 - Refrigerator and method of preserving food - Google Patents

Abstract

An object of the present invention is to effectively utilize carbon dioxide produced by a photocatalytic reaction to suppress a decrease in freshness of a food.
As a means for solving such a problem, a glass member 70 having a photocatalyst layer 71 is mounted on a ceiling portion 42 of a decompression storage chamber 24 provided in a refrigerating chamber of a refrigerator via a sealing member 72 have. On the upper side of the glass member 70, a light source 80 is disposed through a small gap. When the LED 83 of the light source 80 is turned on, the light passes through the glass member 70 and enters the photocatalyst layer 71. Thus, the photocatalyst layer 71 generates radicals from moisture and the like, and decomposes gas or the like from the food into carbon dioxide and water by the radicals. As the carbon dioxide concentration in the storage chamber 24 increases, the respiration of vegetables is suppressed, the enzyme reaction of meat and fish is suppressed, and the propagation of microorganisms is also suppressed.

Description

REFRIGERATOR AND METHOD OF PRESERVING FOOD [0002]

The present invention relates to a refrigerator and a food preservation method.

BACKGROUND ART [0002] A refrigerator using a redox effect of a photocatalyst is known in the prior art. In the first conventional technique, a photocatalytic device is mounted on a side surface of a refrigerator (Patent Document 1). The photocatalytic device of the first prior art has a structure in which a photocatalyst made of a thin film of titanium dioxide is supported and supported on a base having a photocatalytic reaction surface and a light emitting element which is disposed so as to be able to illuminate a predetermined visible light And a diode element (hereinafter LED). The LED mainly emits visible light (light having a wavelength of 400 nm to 800 nm) such as blue, green and red and ultraviolet light (light having a wavelength of 360 to 400 nm). In the second conventional technique, titanium oxide fine particles containing a rutile type in which metal ultrafine particles such as platinum having a particle diameter of 10 nm or less are supported are used as the main component of the photocatalytic film (Patent Document 2). The main component and the binder component are provided on the substrate to form a photocatalytic film. In the second conventional technique, the photocatalytic film is irradiated with light having a wavelength of 360 to 410 nm from the LED. In the third prior art, a honeycomb filter having a photocatalyst is used to deodorize the inside of a refrigerator (Patent Document 3). In the third prior art, decomposition of methyl mercaptan and dimethyl disulfide is promoted by using both a photocatalyst and an oxidation catalyst which react with visible light as a photocatalyst. In the fourth related art, when the temperature in the storage chamber reaches a predetermined temperature range, ultraviolet rays are irradiated from the LED (Patent Document 4).

Japanese Patent Application Laid-Open No. 9-941 Japanese Patent Application Laid-Open No. 2003-290664 Japanese Patent Application Laid-Open No. 2006-17358 Japanese Patent Application Laid-Open No. 2007-3021

In the photocatalytic reaction, odorous component gases and germs are decomposed into carbon dioxide and water. In the prior art, only decomposition of odorous component gas and germs is satisfied, and no consideration is given to the effective utilization of carbon dioxide, which is a decomposition product.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a refrigerator and a food preservation method which can be used for preserving food by increasing carbon dioxide in a storage chamber having a closed structure. It is still another object of the present invention to provide a refrigerator and a food preservation method capable of increasing the concentration of carbon dioxide in a storage chamber by causing a photocatalytic reaction in a storage chamber of a closed structure and suppressing a decrease in freshness of food in the storage chamber by the carbon dioxide .

In order to solve the above problems, a refrigerator according to the present invention is a refrigerator having a storage room for storing food, wherein the storage room has a closed structure, and a carbon dioxide increasing device for increasing carbon dioxide in the storage room is provided.

The carbon dioxide increasing device may be configured to generate carbon dioxide by decomposing the food gas generated in the food stored in the storage room.

The carbon dioxide increasing device may include a light source and a photocatalyst that generates carbon dioxide from the food gas by using the energy of the light ray incident from the light source.

And a light shielding member for suppressing irradiation of the food in the storage room with the light beam output from the light source.

And a decompression device for decompressing the pressure in the storage room.

The pressure of the storage chamber may be lowered to a predetermined pressure by the decompression device, and then the carbon dioxide increasing device may be operated.

1 is a sectional view of a refrigerator according to an embodiment of the present invention;
2 is a sectional view of the decompression storage chamber according to the first embodiment;
3 is an assembled perspective view of the decompression storage chamber.
4 is a side view showing a state before mounting the LED cover in the decompression storage chamber.
5 is a side view showing a state in which the LED cover is attached to the decompression storage chamber.
6 is a side view showing a state in which the LED cover is attached to the decompression storage chamber.
7 is an enlarged view showing a state in which the LED cover is attached to the decompression storage chamber.
8 is an enlarged view showing a state in which an LED cover is attached to the decompression storage chamber.
9 is a top view of the decompression chamber with the LED cover mounted.
10 is an enlarged side view showing a state before the LED substrate is mounted on the LED cover;
11 is an enlarged side view showing a state in which an LED substrate is inserted into an LED cover.
12 is an enlarged side view showing a state in which the LED substrate is mounted on the LED cover.
Fig. 13 is a perspective view of the LED cover before the LED substrate is mounted, as viewed from the back side. Fig.
14 is a perspective view of the LED cover with the LED substrate inserted therein, as viewed from the rear side.
15 is a perspective view of the LED cover with the LED substrate mounted thereon as seen from the back side.
16 is a perspective view and a cross-sectional view of a packing mounted around a glass substrate on which a photocatalyst is formed;
17 is an enlarged cross-sectional view showing the state of the packing before mounting the glass substrate;
18 is an enlarged cross-sectional view showing a state of packing when a glass substrate is mounted;
19 is an enlarged cross-sectional view showing a packing state when an LED cover is mounted on a glass substrate;
20 is a flow chart of a process for controlling the pressure in the decompression storage chamber and controlling the light source.
21 is an explanatory diagram showing a state in which carbon dioxide in the decompression storage chamber is increased by the photocatalytic reaction and the freshness of the food is suppressed.
22 is an experimental graph showing that the concentration change of carbon dioxide and ethylene gas when avocado is accommodated in the decompression chamber differs depending on the presence or absence of the photocatalytic reaction.
FIG. 23 is an experimental graph showing that the concentration of carbon dioxide and odorous component gas changes when the meat or fish is contained in the decompression storage chamber, depending on the presence or absence of the photocatalytic reaction.
24 is an experimental graph showing that the change in the amount of vitamin C remaining in the spinach contained in the decompression depot is different depending on the presence or absence of the photocatalytic reaction.
25 is an experimental graph showing that the change in the amount of vitamin C remaining in the broccoli accommodated in the depressurized depot is different depending on the presence or absence of photocatalytic reaction.
FIG. 26 is an experimental graph showing that the change in the K value of the fish slices of the tuna contained in the decompression depot is different depending on the presence or absence of the photocatalytic reaction.
27 is an experimental graph showing that the change in redness of beef contained in the depressurized depot is different depending on the presence or absence of photocatalytic reaction.
28 is a sectional view of the decompression storage chamber according to the second embodiment;
29 is a sectional view of a refrigerator according to a third embodiment;
30 shows a configuration of an apparatus for increasing carbon dioxide according to a fourth embodiment;
31 is a view showing a state in which the carbon dioxide increasing device is used in a sealed container such as a cooler box.
32 is a cross-sectional view showing a configuration for supplying power to a carbon dioxide increasing device installed in a hermetically sealed container from a solar cell generator provided outside the hermetically sealed container according to the fourth embodiment;

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, as described below, the food is stored in a closed storage room, and the carbon dioxide in the storage room is increased by using the food to suppress the freshness of the food by carbon dioxide.

As an example of a method for increasing carbon dioxide, a photocatalytic reaction can be used. In the photocatalytic reaction, oxygen, hydrogen, and moisture in the air are decomposed to generate radicals having extremely high reactivity, and the radicals decompose odorous component gases or remove germs. In a sealed storage chamber, the moisture of the food becomes a raw material of the radical, and the radical derived from the moisture of the food performs decomposition of the odor component gas and removal of the sterilization. The moisture from the food not only becomes the raw material of the radicals, but is also trapped in a closed storage compartment to create a high humidity environment. Therefore, it is possible to suppress the drying of the food and the deterioration of the flavor.

Further, the redox reaction by the photocatalytic reaction finally decomposes the odorous component gas and the germs into carbon dioxide and water. The decomposition products carbon dioxide and water are trapped in a sealed storage compartment. Water, which is one kind of decomposition product, is reused as a raw material of radicals, and also helps to maintain a high humidity environment. The other decomposition product, carbon dioxide, inhibits the enzymatic reaction of meat and fish, reduces the respiration of vegetables, prevents deterioration, or inhibits the growth of microorganisms.

By carrying out the photocatalytic reaction by preserving the food in a closed storage room, it is possible to use the odor component gas and moisture from the food as a raw material of the radical, and to use the decomposition product of the photocatalytic reaction, such as carbon dioxide, have. In this way, in the sealed storage chamber, the primary effect (decomposition and sterilization of the odor component gas) by the photocatalytic reaction and the secondary effect by the carbon dioxide which is the product of the photocatalytic reaction are generated, have.

For this purpose, in the present embodiment, in a refrigerator having a storage chamber 24 that is sealed when food is stored, the refrigerant is introduced into the inside of the sealed storage chamber 24 in the refrigerator or other member constituting the storage chamber 24, Ultraviolet light or visible light responsive photocatalyst 71 is provided. A light source for irradiating the photocatalyst 71 with visible light or ultraviolet light is provided in the member 20 outside the storage chamber 24 or the storage chamber 24.

When the storage chamber 24 is maintained at a lower pressure than the atmospheric pressure, the carbon dioxide concentration in the storage chamber 24 can be higher than the normal atmospheric carbon dioxide concentration. As a result, a secondary effect of carbon dioxide can be exhibited.

[Example 1]

Hereinafter, a refrigerator according to an embodiment of the present invention will be described with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a vertical cross-sectional view of a refrigerator according to the present embodiment; Fig. 2 is a sectional view of the lowermost space portion of the refrigerating chamber 2. Fig. 3 is a perspective view of the decompression storage chamber 24. Fig.

The refrigerator has a box-shaped refrigerator body 1 and a plurality of doors 6 to 9 which are openably and closably mounted to the opening of the refrigerator body 1. [ The refrigerator main body 1 comprises an outer case 11 made of steel plate, a resin inner case 12, a urethane foamed heat insulator 13 provided between the outer case 11 and the inner case 12, (Not shown). The refrigerator body 1 is provided with a plurality of storage rooms in the order of the refrigerator compartment 2, the freezing compartments 3 and 4, and the vegetables compartment 5 from the top. In other words, the refrigerator compartment 2 is arranged at the uppermost stage and the vegetable compartment 5 is partitioned at the lowest stage. Between the refrigerating compartment 2 and the vegetable compartment 5, the freezing compartments 3 and 4 ) Are disposed (disposed). The refrigerating compartment 2 and the vegetable compartment 5 are storage rooms (for example, about 5 캜) of the refrigeration temperature range. The freezing chambers 3 and 4 are storage rooms of a freezing temperature zone of 0 ° C or lower (for example, a temperature range of about -20 ° C to -18 ° C). These storage rooms 2 to 5 are partitioned by partition walls 33, 34 and 35.

On the front surface of the refrigerator main body 1, doors 6 to 9 for closing the front openings of the storage rooms 2 to 5 are provided. The freezing compartment door 6 has a door for closing a front opening of the refrigerating compartment 2, a freezing compartment door 7 for closing the front opening of the freezing compartment 3, a freezing compartment door 8 for opening the front opening of the freezing compartment 4, The closing door and the vegetable room door (9) are doors that close the front opening of the vegetable room (5). The refrigerator compartment door (6) is constituted as a double-hinged door of right and left hinged type. The freezer compartment door (7), the freezer compartment door (8), and the vegetable compartment door (9) are configured as drawer doors to draw out containers in the storage compartment together with the drawer doors.

In the refrigerator main body 1, a refrigeration cycle is provided. This refrigeration cycle is constituted by connecting in the order of a compressor 14, a condenser (not shown), a capillary tube (not shown), an evaporator 15, and then a compressor 14 in this order. The compressor (14) and the condenser are installed in a machine room provided on the lower side of the rear surface of the refrigerator main body (1). The evaporator 15 is installed in a cooler room provided behind the freezing chambers 3, 4. A blowing fan 16 is provided above the evaporator 15.

The cool air cooled by the evaporator 15 is sent to each storage chamber of the refrigerating chamber 2, the freezing chamber 3, and the vegetable chamber 5 by the blowing fan 16. Specifically, the cool air sent by the blowing fan 16 is sent to a storage room (a refrigerating chamber 2 and a vegetable room 5) of a refrigeration temperature zone through a damper device (not shown) capable of opening and closing. Another part of the cool air is sent to the storage room (freezing room 3, 4) of the freezing temperature zone.

Cool air sent to each storage room of the refrigerator compartment 2, the freezing compartments 3 and 4 and the vegetable compartment 5 by the blowing fan 16 is cooled by cooling the respective storage compartments 2 to 5, And returned to the thread. Thus, the refrigerator of the present embodiment has a circulation structure of cool air, and maintains the respective storage rooms 2 to 5 at appropriate temperatures.

In the refrigerator compartment 2, a plurality of shelves 17-20 made of a transparent resin plate are detachably provided. The lowermost shelf 20 is provided so as to abut the back surface and both side surfaces of the inner case 12 and divides the lowermost space 21, which is the lower space thereof, from the upper space. In addition, a plurality of door pockets 25 to 27 are provided on the inner side of the left and right refrigerating chamber door 6. These door pockets 25 to 27 are provided so as to protrude into the refrigerating chamber 2 in a state where the refrigerating chamber door 6 is closed. On the rear surface of the refrigerating chamber 2, there is provided a back panel 30 which forms a passage through which the cool air supplied from the blowing fan 16 passes.

(Not shown) for supplying the ice-making water to the ice-making vessel of the freezing chamber 3, a storage case (not shown) for storing the food such as dessert, and the like are provided in the lowermost space 21, And a decompression storage chamber 24 for maintaining the freshness and long-term preservation of the food by reducing the pressure in the room. The decompression storage chamber 24 has a width smaller than the width of the refrigerating compartment 2 and is disposed adjacent to the side surface of the refrigerating compartment 2. [

An ice-making water tank and a storage case (not shown) are disposed behind the left-side refrigerating chamber door 6 so as to face each other. Accordingly, the user can take out the ice-making water tank and the storage case only by opening the left-side refrigerating chamber door 6. The decompression storage chamber (24) is disposed on the rear side of the right refrigerating chamber door (6). Accordingly, the user can pull out the food tray 60 of the decompression storage chamber 24 only by opening the refrigerator chamber door 6 on the right side.

The icing water tank and the storage case are located behind the door pocket 27 at the lowermost end of the refrigerator compartment door 6 on the left side. The decompression storage chamber 24 is located behind the door pocket 27 at the lowermost end of the refrigerator compartment door 6 on the right side. The cold air cooled by the evaporator 15 and sent to the refrigerating chamber 2 passes indirectly through the decompression storage chamber 24 to indirectly cool the interior of the decompression storage chamber 24. The arrangement of the ice-making water tank, the storage case and the decompression storage chamber 24 is not limited to this. For example, the storage case may be omitted to increase the size of the decompression storage chamber 24, It may be arranged in a place.

An ice-making water pump (not shown) is provided at the rear of the ice-making water tank. A negative pressure pump 29, which is an example of a decompression device for decompressing the decompression storage chamber 24, is disposed in the space behind the storage case and on the rear side of the decompression storage chamber 24. 3, the negative pressure pump 29 is connected to the pump connection portion provided on the side surface of the decompression storage chamber 24 through the conduit 29A. In the middle of the conduit 29A, a pressure sensor 28 is provided.

The controller (90) controls the operation of the decompression storage chamber (24). The controller 90 may be configured as a part of a controller for controlling the entire refrigerator. The controller 90 controls the operation of the negative pressure pump 29 based on the pressure value in the decompression storage chamber 24 detected by the pressure sensor 28. [

The controller 90 is provided with a door switch 91 for detecting the opening and closing state of the door 6 of the refrigerating compartment 2 and a door switch 91 for detecting the opening and closing states of the door 50 (see Fig. 3) And a food gas sensor 93 for detecting the concentration of the food gas in the decompression storage chamber 24 are connected. 3) of the refrigerator compartment 2 and the decompression compartment 24 are closed, and the door (not shown) of the decompression compartment 24 is closed After confirming that the pressure drops to a predetermined value and that the concentration of the food gas in the decompression chamber 24 becomes a predetermined value or more, a control signal is outputted to the light source 80 so as to be turned on.

2 and 3, the decompression storage chamber 24 includes a box-shaped decompression storage chamber main body 40 having a food entrance opening and a decompression storage chamber door 40 for opening and closing the food access opening of the decompression storage chamber main body 40. [ And a food tray (60) for storing food into and out of the decompression storage chamber door (50). The user can operate the handle 51 of the decompression storage chamber door 50 to open the food entrance opening to draw out the food tray 60 and allow food to enter and exit the food tray 60. [ Specifically, when the user pulls the decompression storage chamber door 50 forward, a pressure release valve provided in a part of the decompression storage chamber door 50 is operated to release the decompression state of the decompression storage chamber 24, do. Thereby, the user can simply open the decompression storage chamber door 50 and enter and exit the food tray 60.

The food tray (60) is provided so as to be movable back and forth in contact with the bottom (43) of the decompression chamber body (40). The food tray 60 is mounted on the back side of the decompression storage chamber door 50 and moves back and forth as the decompression storage chamber door 50 moves. When the user closes the decompression storage chamber door 50 by loading food into the food tray 60, the inside of the decompression storage chamber 24 becomes a sealed state. When the door 50 is closed, the door switch 91 is turned on, the negative pressure pump 29 is driven, and the decompression storage chamber 24 is decompressed to a state lower than the atmospheric pressure. As a result, the oxygen concentration in the decompression storage chamber 24 is lowered, and deterioration of nutritional components in the food can be prevented. Since the door 6 of the refrigerating chamber 2 is normally closed after the decompression chamber door 50 is closed, the door switch 92 of the decompression chamber 24 may be omitted. That is, the door switch 91 of the refrigerating chamber 2 may indirectly determine the opening / closing state of the decompression storage chamber 24.

Further, in this embodiment, the odor component gas and the ethylene gas generated in the food stored in the decompression storage chamber 24 are changed to carbon dioxide by a photocatalytic reaction to be described later. Therefore, in addition to the above effect by the depressurization, the freshness maintenance effect by the change of the gas component in the decompression storage chamber 24 can be expected. In addition, when the decompression storage chamber 24 in the closed state is decompressed, moisture is slightly evaporated from the food stored in the decompression storage chamber 24. By this evaporated water, the interior of the decompression storage chamber 24 becomes a high humidity state (for example, the humidity is close to 100%). In addition, the water evaporated from the food is also used as a raw material for radicals.

On the upper portion of the decompression storage chamber 24, a glass member 70 as an example of a transparent window portion is mounted through a seal member 72. That is, for example, a rectangular opening is formed in the ceiling portion 42 of the decompression storage chamber main body 40, and a quadrangular glass member 70 is attached to the opening through the sealing member 72. The seal member 72 fills the gap between the edge of the glass member 70 and the opening and maintains the hermeticity of the decompression storage chamber 24. The decompression chamber body 40 is warped at the time of decompression, but no gaps occur around the glass member 70 even in this case.

As shown in Fig. 2, a photocatalyst layer 71 is formed on the inner surface of the glass member 70 located on the both sides of the interior of the decompression chamber 24. 2, the thickness of the photocatalyst layer 71 is exaggerated for the sake of understanding.

On the outside of the decompression storage chamber 24, a light source 80 is provided above the glass member 70. It is preferable that the light source 80 and the glass member 70 are arranged as close as possible. This is because the amount of light passing through the glass member 70 and reaching the photocatalyst layer 71 can be increased. It is necessary to increase the output of the light source 80 as the distance between the light source 80 and the glass member 70 increases. It is preferable that the distance between the light source 80 and the glass member 70 (specifically, the photocatalyst layer 71 formed on the glass member 70) is short because light having a short wavelength such as ultraviolet rays is easily attenuated.

The method of mounting the light source 80 in the refrigerator main body 1 can be variously considered. As a first method, a method of providing the light source 80 on the lower surface of the shelf 20 at the lowermost stage, for example, as shown in Fig. 2, can be considered. Since the lower surface of the shelf 20 at the lowest stage is close to the ceiling portion 42 of the decompression chamber body 40, the amount of light absorbed into the photocatalyst layer 71 can be increased by providing the light source 80 therein.

The second method of mounting the light source 80 to the refrigerator main body 1 is as follows. For example, as shown in Fig. 3, the light source 80 is a light source unit detachable from the ceiling part 42 of the decompression storage chamber main body 40 . The light source unit (light source 80) is located on the upper side of the glass member 70 and is detachably mounted on the ceiling portion 42.

Either the first method or the second method may be employed. In the second method, the glass member 70 having the photocatalyst layer 71 and the light source 80 can be integrally provided in the decompression storage chamber 24. In this embodiment, the light source 80 according to the first method is shown in Fig. 2, and the light source 80 according to the second method is shown in Fig. 3 to Fig. The glass member 70 having the photocatalyst layer 71 and the light source 80 may be arranged at the bottom of the decompression storage chamber 24 as in the embodiment described later.

In the first method shown in Fig. 2, the light source 80 is composed of, for example, an LED (Light Emitting Diode) substrate 82 and one or a plurality of LEDs 83 provided on the lower surface side of the LED substrate 82 can do. The LED substrate 82 having the LED 83 can be detachably mounted on the lower surface of the shelf 20.

In the second method shown in Fig. 3, the light source 80 includes an LED substrate 82 (see Fig. 13) provided on the lower surface of the LED 83 and a LED substrate 82 mounted on the ceiling of the decompression chamber body 40 And an LED cover 81 for mounting the light emitting diode on the light emitting diode 42. The LED cover 81 also includes a function of protecting the LED substrate 82.

Here, the wavelength of the light emitted by the light source 80 is examined. The light can be divided into, for example, ultraviolet rays (10 nm to 400 nm), visible light (400 nm to 800 nm), and infrared rays (800 to 4 μm).

When the photocatalyst layer 71 is composed of an ultraviolet light-responsive type catalyst that strongly reacts to ultraviolet light, the light source 80 is also formed of an LED that emits ultraviolet rays. When ultraviolet rays are used, it is necessary to provide a member for preventing the user from facing the light source 80. Off of the light source 80 can be controlled by interlocking with the door switch 91 of the refrigerating compartment 2 or the switch 92 for detecting the operation of the handle 51. [ However, in case of emergency, it is desirable to provide an anti-skid member for preventing the ultraviolet rays from being viewed by the user. On the contrary, in the case where the photocatalyst layer 71 is constituted by a visible light responsive catalyst strongly responsive to visible light, and the light source 80 is constituted by an LED that emits visible light, the above-mentioned member for preventing the sight is unnecessary. Therefore, the use of the visible light responsive photocatalyst layer 71 and the light source 80 for outputting visible light is simplified. Further, when the photocatalytic reaction is caused by the visible light, it is not necessary to provide the member in the space in the refrigerator main body 1 or in the space inside the decompression storage chamber 24, and the capacity of these spaces is not reduced.

However, ultraviolet rays have higher energy than visible rays. Even 350 nm ultraviolet rays having relatively long wavelengths have an energy of 343 kJ / ㏖. The inter-carbon bond C-C forming the resin constituting the decompression storage chamber 24 is 353 kj / mol. Therefore, when ultraviolet rays are irradiated to the resin, a chemical reaction occurs, the polymer chains are cut off, or the carbon at another site sticks to the cut portion and is crosslinked, possibly causing deterioration of the resin. In particular, since the decompression storage chamber 24 needs a sealing structure capable of withstanding a reduced pressure, it is not preferable that the resin deteriorates due to ultraviolet rays.

Thus, in this embodiment, the photocatalytic reaction is obtained by using the visible light-responsive photocatalyst layer 71 and the light source 80 that emits visible light. Among visible light wavelengths, visible light having a wavelength in the vicinity of 470 nm, which has relatively high energy, is used as an example. Since the LED includes advantageous characteristics in terms of lifetime and luminous efficiency, in this embodiment, the light source 80 is composed of an LED. The present invention is not limited to this, and other types of light emitting elements may be used.

As the visible light responsive photocatalyst, for example, titanium oxide treated to react up to the visible light region is known. The present invention is not limited thereto, and tungsten oxide may be used. Since tungsten oxide reacts only with visible light and does not react with ultraviolet rays, when tungsten oxide is used as a photocatalyst, a relatively high reaction efficiency is obtained. Since tungsten oxide does not need to be processed like titanium oxide, the tungsten oxide can be handled easily and the cost for forming the glass member 70 can be reduced. Also in this respect, it is advantageous to use tungsten oxide as a photocatalyst.

The above advantages can be obtained by forming the photocatalyst layer 71 with tungsten oxide. Nevertheless, the photocatalyst layer 71 may be formed of titanium oxide or the like, or another material that reacts with visible light. In addition, a configuration using ultraviolet light may be employed as long as it can disadvantageously obtain a photocatalytic reaction using ultraviolet light.

The substrate (support) for forming the photocatalyst layer 71 is preferably transparent to a light beam capable of supporting a photocatalyst and causing a photocatalytic reaction. Therefore, it is preferable that the substrate is made of glass or resin transparent to visible light.

However, since the resin is an organic substance, if the photocatalyst is directly applied, the resin is deteriorated. When a substrate is formed of a resin, a primer treatment is required. On the other hand, since glass is an inorganic substance, it does not deteriorate even when it is directly applied. Therefore, from the viewpoint of the number of manufacturing steps of the substrate, the material cost, and the like, the substrate carrying the photocatalyst layer 71 is preferably formed of glass. However, the surface of the resin plate may be subjected to a primer treatment to form a transparent protective layer, and the photocatalyst layer 71 may be formed on the protective layer.

By the way, although the effect of the photocatalytic reaction can be enhanced by increasing the thickness dimension of the photocatalyst layer 71, if the thickness dimension is too large, the transparency is lowered. Therefore, the amount of light passing through the photocatalyst layer 71 decreases. Accordingly, when the visible light is used as the illumination in the decompression storage chamber 24, the visibility of the decompression storage chamber 24 is lowered due to the insufficient amount of light. If the photocatalyst layer 71 becomes too thick, the photocatalyst layer 71 may be broken. Thus, in the present embodiment, the thickness of the photocatalyst layer 71 is set so that the amount of transmitted light does not decrease so much and the possibility of physical destruction decreases.

As described above, the visible light transmitted through the glass member 70 from the light source 80 and reaching the photocatalyst layer 71 can be used as an illuminating means for illuminating the interior of the decompression storage chamber 24. However, when light directly reaches the food (planting material) in the decompression storage chamber 24, the nutrient components of the food may be oxidized by the photooxidation reaction, or the food may be discolored. Further, with respect to vegetables, if the light is irradiated with a strong light which differs depending on the wavelength, the photosynthesis reaction is promoted, and there is a possibility of consuming carbon dioxide in the decompression storage chamber 24.

Thus, as shown in Fig. 2, in this embodiment, between the food and the glass member 70, a light shielding plate 41 which is opaque to the light beam from the light source 80 is provided. The light transmitted through the glass member 70 and the photocatalyst layer 71 is blocked by the shielding plate 41 and is not directly irradiated onto the food. In the case of the first method and the second method, the light blocking plate 41 may be provided in the decompression storage chamber 24. (Carbon dioxide, odor component gas, ethylene gas) and moisture flow in the decompression storage chamber 24 through the gap between the shield plate 41 and the ceiling portion 42 as indicated by the dotted line in FIG. The light shielding plate 41 is not necessarily required, but it is only required that the position of the light source 80 is specified so that the food is not directly irradiated with visible light, and oxidation of the nutrient components can be appropriately suppressed.

3 to 19, a structural example in the case of unitizing the glass member 70 having the photocatalyst layer 71 and the light source 80 will be described. 3, the glass member 70 having the photocatalyst layer 71 and the light source unit 80 are detachably mounted on the ceiling portion 42 of the decompression storage chamber main body 40. As shown in Fig.

4 shows a state in which the light source unit 80 is to be mounted after the glass member 70 is mounted to the opening of the ceiling portion 42 through the seal member 72. Fig. Fig. 5 shows a state in which the light source unit 80 is mounted on the upper side of the glass member 70. Fig. Fig. 6 shows a state in which the light source unit 80 is mounted on the upper side of the glass member 70. Fig. Fig. 7 is an enlarged view of a part of Fig. 5. Fig. Similarly, FIG. 8 is an enlarged view of a part of FIG. 9 is a top view of the ceiling part 42 on which the light source unit 80 is mounted.

10 to 15 show a state in which the light source unit 80 is assembled. 10 shows a state before the LED substrate 82 having the LED 83 is mounted in the mounting space 85 formed on the lower surface of the LED cover 81. Fig. 11 shows a state in which the LED substrate 82 is inserted into the mounting space 85 in the LED cover 81. Fig. 12 shows a state in which the LED substrate 82 is mounted in the mounting space 85 in the LED cover 81. FIG.

Fig. 13 is a perspective view of the state shown in Fig. 10 as viewed from the lower side of the LED cover 81. Fig. 14 is a perspective view of the state shown in Fig. 11 as viewed from the lower side of the LED cover 81. Fig. Fig. 15 is a perspective view of the state shown in Fig. 12 as viewed from the lower side of the LED cover 81. Fig.

15, a plurality of (for example, two) support portions 84 are formed on the underside of the LED cover 81 at a lower side of the mounting space 85, and are spaced apart in the width direction. The LED substrate 82 is supported by the supporting portions 84 thereof. The width dimension of the mounting space 85 is set in accordance with the width dimension WL of the LED substrate 82. Therefore, when the LED substrate 82 is mounted in the mounting space 85, Width direction. 12, the supporting portion 84 is inclined. Therefore, by inserting the LED substrate 82 into the mounting space 85, the LED substrate 82 is positioned in the longitudinal direction as well.

Further, since the LED substrate 82 is supported by the plurality of support portions 84 from the lower side, the LED substrate 82 does not fall off naturally from the LED cover 81. The support portion 84 is provided at a position where it does not interfere with the LED 83.

It is also possible to use the LED 83 as a positioning stopper. For example, when the width dimension WL of the LED substrate 82 is made smaller than the width dimension of the mounting space 85, each LED 83 is brought into contact with the nearest supporting portion 84, 82 can be positioned in the width direction. In this way, by providing the LED 83 not only with the light emitting function but also with the positioning stopper function, even when the LED substrate 82 is formed smaller than the mounting space 85, the LED substrate 82 Can be positioned.

16 shows the structure of the seal member 72. Fig. Fig. 16 (a) is a perspective view of the seal member 72, and Fig. 16 (b) is a sectional view of the seal member. A seal lip portion 72A and an auxiliary lip portion 72B formed on the upper and lower sides of the seal lip portion 72A are provided on the outer peripheral surface of the seal member 72. [ The seal lip portion 72A is a member for sealing the interior of the decompression storage chamber 24 in vapor-liquid tightness and the auxiliary lip portion 72B is a member for preventing dust and dirt from intruding toward the seal lip portion 72A .

17 shows a state in which the seal member 72 is placed on the ceiling portion 42 of the decompression chamber body 40. As shown in Fig. Fig. 18 shows a state in which the glass member 70 is placed on the upper surface side of the seal member 72. Fig. Fig. 19 also shows a state in which the light source unit 80 is placed on the glass member 70. Fig. 18 and 19, it is not necessary to form the photocatalyst layer 71 on the entire lower surface (inner side surface) of the glass member 70, but only on the region exposed in the decompression storage chamber 24 .

Referring to Fig. 20, the photocatalytic action in the decompression storage chamber 24 will be described. When visible light containing light of a predetermined wavelength (for example, around 470 nm) is output from the LED 83 of the light source 80, the visible light passes through the glass member 70 and enters the photocatalyst layer 71. When visible light is incident on the photocatalyst layer 71, electrons and holes are generated. Since the hole has a positive electric charge, it takes away electrons from water (H ₂ O) and generates OH radicals and hydrogen radicals. Further, the electrons generated in the photocatalyst layer 71 are transferred to oxygen molecules to generate oxygen radicals. Moisture slightly evaporated from the food in the decompression storage chamber 24 comes into contact with the photocatalyst layer 71 to become a raw material of the radical.

The radical decomposes the gas (for example, ethylene gas, methyl mercaptan, disulfide dimethyl) from the food and the minute organic matter (for example, bacteria) floating in the decompression storage chamber 24 into carbon dioxide and water. As an example, the decomposition reaction of ethylene gas generated in vegetables is represented by the following chemical formula (1).

C ₂ H ₄ + 4O ₂ ? 2CO ₂ + 2H ₂ O (1)

As can be seen from the formula (1), the ethylene gas generated from vegetables reacts with oxygen in the air to produce carbon dioxide and water. The vegetables in the decompression storage chamber 24 are alive and breathe according to the concentration ratio of oxygen and carbon dioxide in the air. When the concentration of carbon dioxide in the decompression storage chamber 24 is increased, the pores of the vegetables are closed and the respiration activity is suppressed, so that deterioration of the vegetables is suppressed. Therefore, deterioration of taste and nutrition can be prevented over a relatively long period of time.

Since the meat and fish stored in the decompression storage chamber 24 are already dead, they are different from the freshness maintenance mechanism of vegetables. However, odor component gas and organic gas generated from meat and fish are also decomposed into carbon dioxide and water by the photocatalytic reaction.

The carbon dioxide generated by the photocatalytic reaction easily dissolves in water. Therefore, carbon dioxide, which is a product of the photocatalytic reaction, is dissolved in water on the surface of the food to become carbonic acid. Carbonic acid changes the pH value of food surface. If the pH value of the food surface changes, it will be inconsistent with the optimal pH of the microorganisms present on the food surface. Therefore, the propagation of microorganisms is suppressed.

In addition, since the optimum pH is also present in the enzymatic reaction in the food, the pH value of the food is changed, so that the enzyme reaction can be suppressed. The freshness of meat and fish decreases with the progress of the enzyme reaction. Therefore, the freshness of meat and fish can be maintained relatively long by inhibiting the enzyme reaction by changing the pH value of the food.

Further, since the photocatalyst decomposes the odor component gas in the decompression storage chamber 24, the decompression storage chamber 24 can be deodorized. Further, when moisture is present in the decompression storage chamber 24, radicals are generated by the action of the photocatalyst. Therefore, the inside of the decompression storage chamber 24 can be sterilized by the action of radicals.

When the carbon dioxide in the decompression storage chamber 24 is increased in this manner, the freshness of the meat and the fish can be suppressed from deteriorating and the deterioration of the quality of vegetables can be suppressed. However, oxidation of food can not be suppressed only by carbon dioxide. In the case of meat and fish, when the oxidation reaction occurs, the fatty acid deteriorates or the vitamins and the like deteriorate.

On the other hand, the storage chamber 24 of the present embodiment is a decompression storage chamber not only having a high degree of carbon dioxide but also being maintained in a state lower than atmospheric pressure. That is, the ratio of the oxygen concentration in the decompression storage chamber 24 is lower than the normal atmosphere, and conversely, the ratio of the carbon dioxide concentration in the decompression storage chamber 24 is higher than the normal atmosphere.

Typical atmospheric components are oxygen 21% and carbon dioxide 0.4%. Nitrogen and other minor components are omitted. If the pressure in the decompression storage chamber 24 is lowered by 20% than the atmospheric pressure, the oxygen content is 16% and the carbon dioxide is 0.032% as compared with the composition at the atmospheric pressure. Since the carbon dioxide is generated in the decompression storage chamber 24 by the photocatalytic reaction, for example, the carbon dioxide concentration of the decompression storage chamber 24 rises to a value of about 0.13%. These specific numerical values are only examples for understanding the operation and effect of the present embodiment, and the present invention is not limited to these numerical values.

Thus, in the decompression storage chamber 24 of the present embodiment, the oxygen concentration is reduced due to the decompression and the decomposition product of carbon dioxide is increased by the photocatalytic reaction. The relative lowering of the oxygen concentration by the decompression can suppress the oxidation reaction and maintain the freshness of meat and fish relatively long. In addition, as described above, the increase of carbon dioxide prevents the degradation by inhibiting the enzyme reaction of meat and fish, inhibiting the growth of microorganisms, or suppressing the respiration of vegetables.

In addition, since the decompression storage chamber 24 of this embodiment preserves food in a reduced pressure state, the life of the radical can be prolonged as compared with that at a normal atmospheric pressure, decomposition reaction of food gas such as ethylene gas, It is considered that the efficiency of the reaction can be improved. In general, radicals and ions generated in the photocatalyst layer 71 react with molecules in the air and disappear immediately. However, in the reduced pressure state, the molecules in the decompression storage chamber 24 decrease and the reaction rate is slowed down. Therefore, it is considered that the lifetime of radicals and ions is increased.

An example of a control method of the decompression storage chamber 24 will be described with reference to Fig. The processing shown in Fig. 21 is executed by the controller 90. Fig. The processing shown in Fig. 21 may be realized as a computer program or as a hardware circuit.

The controller 90 determines whether the door 50 is closed based on a signal from the door switch 92 for detecting the open / closed state of the door 50 of the decompression storage chamber 24 (S10). When the door 50 of the decompression storage chamber 24 is closed (S10: YES), the controller 90 sends a signal from the door switch 91 for detecting the open / closed state of the door 6 of the refrigerating chamber 2 And determines whether the door 6 is closed (S11). If the door switch 92 of the decompression storage chamber 24 is omitted and the door switch 96 of the refrigerating chamber 2 indirectly determines opening and closing of the door 50 of the decompression storage chamber 24, Is omitted.

The controller 90 outputs a control signal to the negative pressure pump 29 and drives it (S12). When it is confirmed that the door 6 of the refrigerating compartment 2 is closed (S11: YES) Air is discharged. When either the door 6 or the door 50 is not closed (S10: NO or S11: NO), the process returns to step S10.

The controller 90 monitors the detection signal from the pressure sensor 28 and determines whether or not the pressure P1 of the decompression storage chamber 24 is equal to or less than a predetermined pressure Pth set in advance (S13). The controller 90 operates the negative pressure pump 29 until the pressure P1 of the decompression storage chamber 24 becomes the predetermined pressure Pth or less (S13: NO). The controller 90 stops the negative pressure pump 29 (S14) when the pressure P1 of the decompression reservoir 24 becomes the predetermined pressure Pth or less (S13: YES).

After the decompression storage chamber 24 is depressurized, the controller 90 determines whether or not the concentration GC2 of the food gas in the decompression storage chamber 24 is lower than a predetermined gas concentration (for example, GCTh) (S15).

Here, the threshold value GCTh of the gas concentration can be prepared for each type of food gas, such as a threshold value for ethylene gas, a threshold value for methylmercaptan, a threshold value for dimethyl disulfide, and the like. When the gas concentration of any one of the plural kinds of food gas reaches the threshold value (S15: YES), the controller 90 lights the light source 80 (S16). Thereby, as described above, the photocatalytic reaction is performed under a reduced pressure environment, and the food gas is decomposed into carbon dioxide and water. When all of the concentration of the target food gas is below the threshold value (S15: NO), the controller 90 turns off the light source 80 (S17).

Alternatively, the step S15 may be omitted and the light source 80 may be turned on for a predetermined period of time. In this case, steps S15 and S17 are removed from the flowchart of Fig. 21, and the process immediately moves to step S16 in step S14. Then, in step S16, the light source for photocatalyst is turned on, and the light source for photocatalyst is turned on for a predetermined time. The step S16A can be assigned to this improved step.

Alternatively, the light source 80 may be used as a lighting device of the decompression storage chamber 24, so that the light source 80 may be turned on while the door 6 of the refrigerator compartment 2 is opened. Alternatively, the intensity of the light emitted from the light source 80 and / or the wavelength of the light may be switched according to the situation. For example, when the light source 80 is used as a lighting device of the decompression storage chamber 24, when only a part of the LEDs 83 of the plurality of LEDs 83 are used for lighting up the photocatalytic reaction All of the LEDs 83 may be turned on. Alternatively, the LED 83, which can output light of different wavelengths, may be mounted with the light source 80 so that the wavelength when the LED 83 is used as an illumination device and the wavelength when promoting the photocatalytic reaction are made different. When the light source 80 is used as a lighting device, the number of lit LEDs 83 is reduced and the wavelength is increased. When the light source 80 is used as a promoter of the photocatalytic reaction, The combination of the light intensity and the wavelength may be different depending on the situation of the refrigerator, such as increasing the lighting number of the refrigerator and shortening the wavelength.

The increase in carbon dioxide due to the photocatalytic action will be described with reference to FIGS. 22 and 23. FIG. FIG. 22 shows a time change of the carbon dioxide concentration and a change in the concentration of the ethylene gas when the avocado, which generates a large amount of ethylene gas to promote deterioration of vegetables, is accommodated in a confined space.

Characteristic line G10 shows the time variation of the carbon dioxide concentration when the photocatalyst is used. The characteristic line G11 represents the time variation of the carbon dioxide concentration when the photocatalyst is not used. The characteristic line G12 represents the change in the ethylene concentration over time when the photocatalyst is used. The characteristic line G13 represents a time change when the photocatalyst is not used.

When the photocatalyst is not used, the concentration of the ethylene gas is maintained at a substantially constant value (G13), although the concentration of the ethylene gas gradually increases after the avocado is accommodated. When the photocatalyst is not used, the concentration of carbon dioxide is almost constant (G11). On the other hand, when a photocatalyst is used, since the ethylene gas is decomposed into carbon dioxide and water by the photocatalyst layer 71, the concentration of the ethylene gas is lowered with the lapse of time (G12). Carbon dioxide, which is a decomposition product of ethylene gas, increases with the lapse of time (G10).

Therefore, it can be seen that the ethylene gas generated from the vegetables is decomposed by the photocatalyst to generate carbon dioxide. In a confined space, since the carbon dioxide is hardly leaked to the outside, the concentration of carbon dioxide in the confined space increases. Since carbon dioxide inhibits the respiration of vegetables, it is possible to suppress the freshness of vegetables. In addition, vegetables have a feature of performing photosynthesis when light comes in contact. Vegetables react with red light around 630nm to synthesize photosynthesis. Since the LED 83 of this embodiment mainly outputs light having a wavelength in the vicinity of 470 nm, photosynthesis of vegetables can be suppressed.

Fig. 23 shows the change over time of the carbon dioxide concentration and the change over time of the odorous component gas concentration when meat or fish is stored in the closed space.

The characteristic line G14 represents the time variation of the concentration of carbon dioxide when the photocatalyst is not used. The characteristic line G15 represents the time variation of the carbon dioxide concentration when the photocatalyst is used. The characteristic line G16 shows the change with time of the concentration of the odorous component gas when the photocatalyst is not used. The characteristic line G17 shows the change with time of the odor component gas when the photocatalyst is used.

When the photocatalyst is not used, since the odor component gas generated from the meat or fish can not be decomposed, the concentration of the odor component gradually increases (G16). When no photocatalyst is used, no carbon dioxide is produced as a result of the photocatalytic reaction, and the concentration of carbon dioxide is almost constant (G14). On the other hand, when a photocatalyst is used, since the odorous component gas is decomposed into carbon dioxide and water by the photocatalyst, its concentration decreases with time (G17). Since carbon dioxide is generated by the photocatalytic reaction, the concentration of carbon dioxide increases with time (G15).

As shown in Fig. 23, when a photocatalyst is actuated in the state of preserving meat and fish, the odorous component gas is decomposed and the carbon dioxide is increased, the enzyme reaction is suppressed by the carbon dioxide, and the propagation of microorganisms is suppressed. Therefore, the freshness of meat and fish can be suppressed from being lowered.

24 to 26, the freshness-retaining effect by carbon dioxide when vegetables, meat, and fish are stored will be described. 24 to 26 are graphs in the case where the remaining amount of vitamin C when the spinach, broccoli and avocado are stored in the closed space for 3 days is compared with the presence or absence of the photocatalyst. Fig. 24 shows a case in which the spinach and the avocado are housed in a confined space. Fig. 25 shows a case where broccoli and avocado are contained in a confined space. Since avocado is a food that easily generates ethylene gas, it is used for generating ethylene gas.

Fig. 24 shows the result of comparing the residual amount of vitamin C (G22) of the spinach with a photocatalyst and the residual amount of vitamin C (G21) of the spinach when the photocatalyst is not used. It can be seen that the residual amount of vitamin C (G20) in the spinach when the photocatalyst is activated is larger than the residual amount of vitamin C (G23) in the case of not using the photocatalyst.

Fig. 25 shows the result of comparing the residual amount of vitamin C (G22) of broccoli when a photocatalyst is used and the residual amount of vitamin C (G23) of broccoli when no photocatalyst is used. It can be seen that the residual amount of vitamin C (G22) when the photocatalyst is used is larger than the amount of residual vitamin C when the photocatalyst is not used. From the above experimental results, it was confirmed that the decrease of the freshness of the vegetables can be suppressed by increasing the carbon dioxide.

26 and Fig. 27, changes in freshness of animal foods (meat, fish) will be described. Fig. 26 shows a case where tuna is stored in a closed space for 3 days. The K value (G24) of the tuna when the photocatalyst is used is lower than the K value (G25) when the photocatalyst is not used. As a result, it can be seen that the decrease in freshness of the tuna is suppressed by the increase of carbon dioxide.

Fig. 27 shows a change in redness when beef is stored in a closed space for 3 days. It can be seen that the redness G26 in the case of using a photocatalyst is less changed than the redness G27 in the case of not using the photocatalyst and the discoloration of the meat is suppressed.

In this embodiment configured as described above, the concentration of carbon dioxide in the decompression chamber 24 of the closed space can be increased. Therefore, it is possible to prevent the degradation of the vegetable by inhibiting the respiration of the vegetable, suppress the propagation of the microorganism, and reduce the enzyme reaction of food such as meat or fish. Therefore, the effect of maintaining the freshness of the food is higher than in the case of not increasing the carbon dioxide concentration.

In this embodiment, since the photocatalytic reaction is caused in the sealed decompression storage chamber 24, carbon dioxide, which is a product of the photocatalytic reaction, can be trapped in the decompression storage chamber 24 and the concentration of carbon dioxide can be effectively increased. Therefore, the above-described freshness-retaining action by carbon dioxide can be efficiently obtained.

In the present embodiment, moisture that evaporates slightly from the food stored in the decompression storage chamber 24 is used as a raw material of the radical, and the odorous component gas and the germs and the like are decomposed into carbon dioxide and water by the radicals. The decomposition products carbon dioxide and water are trapped in a sealed storage compartment. The moisture is reused as a raw material of the radical, and the moisture of the decompression storage chamber 24 is maintained at a high level. Carbon dioxide realizes the above-described freshness-retaining action.

In this embodiment, the food is stored in the sealed decompression storage chamber 24 and subjected to the photocatalytic reaction, whereby odorous component gas and moisture are used as the raw material of the radical, and the decomposition product of the photocatalytic reaction, . In this way, the photocatalytic action of the decomposition and the eradication of the odor component gas by the photocatalytic reaction in the almost closed environment can be combined with the action of the carbon dioxide, and the drop of the freshness of the food can be suppressed.

Further, in this embodiment, since the sealed decompression storage chamber 24 is made lower than the atmospheric pressure to increase carbon dioxide, the concentration of carbon dioxide in the decompression storage chamber 24 can be efficiently increased. Further, since the inside of the storage chamber 24 is decompressed, it is possible to suppress the leakage of carbon dioxide to the outside of the storage chamber 24. This is because the air pressure outside the storage chamber 24 is high. Further, since the number of air molecules in the storage chamber 24 can be reduced, the lifetime of the radical can be prolonged, and the possibility that the radical decomposes the odor component gas and the germs can be increased.

[Example 2]

The second embodiment will be described with reference to Fig. Each of the following embodiments including the present embodiment corresponds to a modified example of the first embodiment, and therefore, differences from the first embodiment will be mainly described. In this embodiment, a mechanism for performing the photocatalyst is disposed on the bottom surface side of the decompression storage chamber 24. [

28 is provided with a glass member 70 having a photocatalyst layer 71 through a seal member 72 at a central portion of a bottom portion 43 of the decompression storage chamber body 40. The glass member On the upper side of the photocatalyst layer 71, a food tray 60 is provided through a gap. The odor component gas or the like derived from the food in the food tray 60 enters through the gap between the food tray 60 and the photocatalyst layer 71 and is decomposed in the photocatalyst layer 71. Carbon dioxide and moisture, which are decomposition products of the photocatalytic reaction, enter the interior of the food tray 60 through the gaps and inhibit the enzymatic reaction and respiration of the food or inhibit the propagation of microorganisms.

When the food tray 60 is formed of a transparent material, the light from the light source 80 is irradiated on the food in the food tray 60, and the food may deteriorate due to photo-oxidation reaction or the like. In this case, a metal plate 41 formed of aluminum or stainless steel may be provided on the bottom of the food tray 60. This metal plate 41 not only has the function of the light shielding plate described in the first embodiment, but also has the effect of taking the heat of the food and cooling it.

This embodiment having such a configuration also brings about the same effect as the first embodiment. In this embodiment, since the photocatalyst layer 71 and the light source 80 are provided in the bottom portion 43 of the decompression storage chamber 24, the heat radiation plate 41 for promoting the cooling can be provided on the bottom portion 43 of the decompression storage chamber 24, It can also be used as a light shielding plate for preventing light from being irradiated on food. Since one metal plate 41 can have a plurality of functions, it is possible to enhance the performance of the decompression storage chamber 24 while suppressing an increase in manufacturing cost.

[Example 3]

The third embodiment will be described with reference to Fig. 29 is a cross-sectional view of the refrigerator of this embodiment. A glass member 70 having a photocatalyst layer 71 and a light source 80 are arranged on the ceiling of the vegetable compartment 5, for example. Generally, the vegetable compartment 5 has a lower air-tightness than the decompression compartment 24. However, if the air-tightness can be obtained, the concentration of carbon dioxide can be increased by the photocatalytic reaction to suppress the respiration of vegetables. The whole or a part of the vegetable compartment 5 may be airtightly formed to cause a photocatalytic reaction in the airtight space.

[Example 4]

The fourth embodiment will be described with reference to FIGS. 30 and 31. FIG. In this embodiment, an apparatus for generating a photocatalytic reaction is constructed by being separated from a closed space such as a decompression storage chamber 24.

30A, a photocatalytic reaction generator 200 for generating a photocatalytic reaction includes, for example, a photocatalytic section 210 having a photocatalytic layer 212 formed on its inner surface, a photocatalytic section 210 having a photocatalytic section 210, And a power supply unit 230 for supplying power to the light source unit 220. The power supply unit 230 may include a light source unit 220,

FIG. 30 (b) is a sectional view of the photocatalyst 210. FIG. The photocatalyst unit 210 includes a support member 211 formed of, for example, an opaque resin material or a metal material, such as a cylindrical, triangular, square, pentagonal or hexagonal tube, And a photocatalyst layer 212 formed on the entire inner surface or a predetermined region of the photocatalyst layer 212. The support member 211 is opaque in order to reduce the possibility that the light generated in the support member 211 is directly irradiated onto the food. Therefore, a mesh member or the like for suppressing leakage of light may be provided in the openings on both end sides of the support member 211. [

The light source unit 220 includes an LED substrate 221 disposed inside the support member 211 and an LED 222 mounted on the LED substrate 221 at least one. In the present embodiment, a plurality of LEDs 222 are arranged at a predetermined interval apart along the longitudinal center line of the elongated plate-shaped LED substrate 221.

The LEDs 222 are arranged to illuminate the upper and lower surfaces of the LED substrate 221 in both directions. As a first method, for example, the LED 222 may be embedded at the center in the thickness direction of the LED substrate 221, and light may be irradiated from the LED 222 toward the upper and lower surfaces. As a second method, LEDs 222 may be provided on the upper and lower surfaces of the LED substrate 221, respectively. The first configuration has a lower manufacturing cost than the second method.

The power supply unit 230 is composed of, for example, a battery, a battery, a household electric lamp or the like, and is connected to the light source unit 220 through an electric wire 231. Power is supplied from the power supply unit 230 to the LED 222 of the light source unit 220 by turning on the switch 232. [ Alternatively, a timer may be provided so that the switch 232 is turned off when a predetermined time has elapsed after the switch 232 is turned on.

Fig. 31 is a schematic diagram showing an example of using the photocatalytic reaction generator 200. Fig. For example, the food and photocatalytic reaction generator 200 are accommodated in the openable and closable closed container 300 such as a cooler box, and the lid 301 is closed. As a result, the concentration of carbon dioxide in the hermetically sealed container 300 increases, and the same effect as that of the first embodiment is obtained.

Since the closed container 300 and the photocatalytic reaction generator 200 are separately formed in this embodiment, the photocatalytic reaction generator 200 is installed in a container having some degree of hermeticity such as a cooler box and a lunch box. By acceptance, the decrease in freshness of the food can be suppressed. Further, the photocatalytic reaction generator 200 used in any of the closed containers 300 can be used for the other closed container 300, which is easy to use. Further, the hermetically sealed container 300 need not have complete airtightness. (Gas such as food gas, carbon dioxide, etc.) may not be freely circulated inside and outside the container. The higher the airtightness of the container, the more efficiently the carbon dioxide concentration and the lowering of the freshness of the food can be suppressed.

The configuration of the photocatalytic portion 210 is not limited to the cylindrical shape. A gas or the like from the food can reach the photocatalyst layer 212 and the carbon dioxide generated in the photocatalyst layer 212 can flow toward the food. For example, it may be configured as a honeycomb shape or a spherical shape having an opening.

[Example 5]

The fifth embodiment will be described with reference to Fig. In the photocatalytic reaction generator 200 of the present embodiment, the power supply unit 230 is configured as a solar power generator. The power supply unit 230 configured as a photovoltaic power generation device is installed, for example, on the outer surface of the lid 301 of the hermetic container 300. The power supply unit 230 and the light source unit 210 are connected through the electric wire 231 provided through the cover 301. [ The electric wire 231 is mounted on the cover 301 through a sealing member (not shown) such as an O-ring. The power supply unit 230 may be provided with a switch 232 or a timer. Further, the power supply unit 230 may include a battery, a battery, and the like as an auxiliary power supply.

A manual suction pump 310 may be provided in the sealed container 300. The suction pump 310 is mounted on the main body or the cover 301 of the closed container 300 through a seal member (not shown) such as an O-ring. The user closes the lid 301 and manually operates the suction pump 310 after preserving the food in the closed container 300. [ Thereby, air in the hermetically sealed container 300 is sucked and discharged to the atmosphere. The light source unit 210 may be turned on before the inside of the closed container 300 is depressurized by the suction pump 310 or may be turned on after the pressure is reduced. Further, the suction pump 310 may be configured as a full-blown suction pump that operates as a power supply from the power supply unit 230.

This embodiment having such a configuration also brings about the same effect as the fourth embodiment. Further, in this embodiment, since the power supply unit 230 is configured as a solar power generation device, it is possible to suppress the drop of the freshness of food even in places such as mountains, the sea and desert, and is easy to use. In the example shown in the fourth embodiment, a manual or electric suction pump may also be provided. When the electric pump is installed, the power supply unit 230 and the suction pump 310 are electrically connected by the electric wire 232. The electric wire 232 may be provided in the closed container 300 or on the surface of the closed container 300 or inside the wall of the closed container 300.

The present invention is not limited to the above-described embodiments. Those skilled in the art will recognize that various additions and modifications can be made within the scope of the present invention.

For example, the configuration shown in the fourth embodiment or the fifth embodiment may be expressed as follows. The reference numerals assigned to the constituent elements are merely examples for the sake of understanding and are not intended to be limited to the constitution showing the constitution of the following invention.

Expression 1.

A photocatalytic reaction generator (200) for generating a photocatalytic reaction in a container for containing food,

A photocatalyst 210 having a photocatalyst layer 212,

A light source 220 for irradiating the photocatalyst layer with light,

And a power supply unit (230) for supplying power to the light source unit.

Expression 2.

The photocatalytic reaction generator according to claim 1, wherein the photocatalytic unit, the light source unit, and the power source unit are integrated with each other and are capable of entering and exiting the container.

Expression 3.

The photocatalytic reaction generator according to claim 1, wherein the photocatalyst unit and the light source unit are installed inside the container, and the power source unit is configured as a solar power generator for generating sunlight and is installed outside the container.

Expression 4.

The photocatalytic reaction generator according to any one of Formulas 1 to 3, wherein the container is provided with a suction device (310) for sucking and discharging the air inside the container.

1: refrigerator main body 2: refrigerator room 3: 3,4: freezing room 5: vegetable room 6: 9: door 24: decompression storage chamber 28: pressure sensor 29: pump 40: decompression chamber main body 41: A bottom part of the decompression storage chamber, 60: a food tray, 70: a glass member, 71: a photocatalyst layer, 72: a sealing member, 80: a light source, 81: an LED cover, 82: The present invention relates to a photocatalytic reaction device and a photocatalytic reaction device which are provided with a photocatalytic reaction unit and a photocatalytic reaction unit. And a light emitting diode (LED) substrate, wherein the light emitting diode (LED) substrate includes a light emitting diode (LED), a power supply unit,

Claims (9)

A refrigerator having a storage room for storing food,
The storage chamber has a closed structure,
A carbon dioxide increasing device for increasing the carbon dioxide in the closed structure is provided,
The carbon dioxide increasing device includes:
A glass disposed in an opening formed in a portion of the closed structure,
A photocatalyst layer formed on the surface of the glass on the closed structure side and
And a light source located on the outer side of the closed structure and on the outer side opposite to the glass,
Wherein a light ray is incident on the photocatalyst layer from the light source to decompose the food gas generated in the food stored in the sealed structure to increase the concentration of carbon dioxide in the sealed structure. The method according to claim 1,
And a light shielding member for restraining light emitted from the light source from being irradiated on food in the storage room. 3. The method according to claim 1 or 2,
And a decompression device for decompressing the pressure in the storage compartment. The method of claim 3,
Wherein the decompression device reduces the pressure of the storage chamber to a predetermined pressure, and then operates the carbon dioxide increasing device. delete delete delete delete delete

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