JP2001355957A - Refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerator for easily controlling the freshness of food without much trouble some work. SOLUTION: A gas sensor 31 is fitted to a ceiling part in a cold room 4. The gas sensor 31 outputs a concentration signal according to gas concentration being emitted from food in the process of decaying of the food, the presence or absence of the decaying of the food is judged based on the concentration signal from the gas sensor 31, and a judgment result is displayed on a liquid crystal display 28. In the case of this configuration, a user does not need to perform a troublesome operation for inputting the type of food and an appreciation period, and the freshness of the food can be controlled easily simply by confirming the display details on the liquid crystal display 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a refrigerator having a function of controlling the freshness of food.

[0002]

In a general household, the number of foods in a storage room and the expiration date are not precisely controlled. For this reason, the expired food may be hidden behind other foods and may not be seen, or the odor of the expired food may not be noticed and the food may be spoiled. To cope with this, it is conceivable that the user inputs the type of food and the expiration date, and the microcomputer manages the expiration date of the food based on the input data. Is troublesome. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a refrigerator capable of easily and easily managing the freshness of food.

[0003]

According to a first aspect of the present invention, there is provided a refrigerator for storing a food in which a food is stored and outputting an electric signal in accordance with the concentration of gas released in the process of spoiling the food. It is characterized by including a gas sensor, freshness determining means for determining freshness of food based on an output signal from the gas sensor, and display means for displaying a determination result of the freshness determining means. According to the above means, the freshness of the food is determined based on the output signal from the gas sensor, and the determination result of the freshness is displayed on the display means. This eliminates the need for the user to perform a troublesome operation of inputting the type of food and the expiration date, and the freshness of the food can be easily managed only by checking the display on the display means.

[0004] In the refrigerator according to the second aspect, the freshness judging means distinguishes the freshness of the food into three or more levels based on the output signal from the gas sensor, and displays the freshness of the food in the three or more levels on the display means. However, it has features. According to the above means, for example, the freshness of food is a cautionary level such as "Is freshness reduced?", A definitive level "Freshness is degraded", and a warning "Decaying". Can be displayed in different levels, so that the user can easily process the food, such as eating or discarding the food early.

[0005] The refrigerator according to claim 3 is characterized in that a gas sensor for detecting a gas whose specific gravity is heavier or lighter than air is provided at the bottom or ceiling in the storage room. According to the above-described means, the gas released from the food is concentrated at the bottom gas sensor or the gas sensor at the ceiling with a specific gravity, so that the freshness of the food is accurately determined.

In the refrigerator according to the present invention, a plurality of gas sensors for the same kind of gas are provided in different portions of the storage room, and the freshness judging means detects the food whose freshness is decreasing based on output signals from the plurality of gas sensors. It is characterized in that the storage location is determined, and the storage location of the food item whose freshness is decreasing is displayed on the display means. According to the above-described means, since the location of the food whose freshness is decreasing is stored in the storage room, it is easy for the user to search for the food whose freshness is decreasing.

According to a fifth aspect of the present invention, in the refrigerator, a plurality of gas sensors for different types of gas are provided in the same portion in the storage room.
It is characterized in that freshness determining means determines the type of food whose freshness is decreasing based on output signals from the plurality of gas sensors, and the type of food whose freshness is decreasing is displayed on the display means. According to the above-mentioned means, since what is the food whose freshness is decreasing is displayed, it becomes easy for the user to search for the food whose freshness is decreasing.

[0008]

FIG. 1 shows a first embodiment of the present invention.
A description will be given with reference to FIG. First, in FIG.
The cabinet 1 has a box shape with an open front, and a horizontal partition plate 2 is fixed in the cabinet 1.
A plurality of cold air circulation holes 3 (only one is shown) in the partition plate 2
Are formed. The partition plate 2 defines a refrigerator compartment 4 in the upper part of the cabinet 1, and an R door 5 is attached to the front end of the refrigerator compartment 4 so as to be rotatable around the right side in FIG. I have.

As shown in FIG. 4, a horizontal heat insulating partition plate 6 is fixed below the partition plate 2 in the cabinet 1, and a space between the heat insulating partition plate 6 and the partition plate 2 is provided. A vegetable room 7 is formed. The vegetable compartment 7 communicates with the inside of the refrigerator compartment 4 through the cool air circulation hole 3 of the partition plate 2, and a V-door 8 is mounted at the front end of the vegetable compartment 7 so as to be slidable in the front-rear direction. The refrigerator compartment 4 and the vegetable compartment 7 correspond to a storage compartment.

As shown in FIG. 1, an L-shaped heat insulating partition plate 9 is fixed in the cabinet 1 below the heat insulating partition plate 6. A select room 10 and an ice making room 11 are formed on the right and left sides of the heat insulating partition plate 9.
The door 12 and the I-door 13 are slidably mounted in the front-rear direction. A freezing room 14 is formed below the select room 10 and the ice making room 11, and an F door 15 is mounted on a front end of the freezing room 14 so as to be slidable in the front-rear direction.

As shown in FIG. 4, an R cool air generating chamber 16 and an F cold air generating chamber 17 are formed in the cabinet 1 behind the vegetable room 7 and the freezing room 14.
An R evaporator 18 and an F evaporator 19 are provided in the R cool air generation chamber 16 and the F cool air generation chamber 17, and the R evaporator 18 and the F evaporator 19 are connected to a common compressor 20. The compressor 20 supplies a refrigerant to the R evaporator 18 and the F evaporator 19, and is provided at the bottom in the cabinet 1.

From the compressor 20 to the R evaporator 18
And a refrigerant pipe connected to the F evaporator 19
1 (see FIG. 3). This valve 21 is R
The mode is switched between the F mode and the F mode. In the RF mode, the refrigerant discharged from the compressor 20 is supplied to both the R evaporator 18 and the F evaporator 19, and is supplied only to the F evaporator 19 in the F mode.

As shown in FIG. 4, an R fan device 22 is provided in the R cool air generation chamber 16. The R fan device 22 includes an air flow returning from the inside of the R cool air generation chamber 16 to the inside of the R cool air generation chamber 16 through the inside of the vegetable room 7 and from the inside of the R cool air generation chamber 16 to the inside of the refrigerator compartment 4 as indicated by arrows. And vegetable room 7
And an air flow returning to the R-cooled air generation chamber 16 through the inside. When the R fan device 22 is operated in the RF mode, the R evaporator 18 cools both air flows based on the cooling air. The inside of the refrigerator compartment 4 and the inside of the vegetable compartment 7 are cooled.

An F fan device 23 is provided in the F cold air generation chamber 17.
Are arranged. The F fan device 23 generates an airflow that returns from the inside of the F cold air generation chamber 17 to the inside of the F cold air generation chamber 17 through the inside of the ice making chamber 11 and the freezing chamber 14 as indicated by an arrow, as indicated by an arrow. When the F fan device 23 is operated in the mode and the F mode, the F evaporator 1
9 cools the air flow and cools
Cool inside.

As shown in FIG. 1, an operation panel 24 is fixed on the front surface of the R door 5, and an R temperature switch 25 and an F temperature switch 26 are mounted on the front surface of the operation panel 24. An operation control device 27 (see FIG. 3) is provided in the cabinet 1, and the R temperature switch 25 and the F temperature switch 26 are, as shown in FIG.
It is electrically connected to the input terminal of the operation control device 27. The operation control device 27 is mainly composed of a microcomputer, and based on an output signal from the R temperature switch 25 and an output signal from the F temperature switch 26, the inside temperature Tr of the refrigerator compartment 4 and the freezing compartment 14 Is set.

As shown in FIG. 1, a liquid crystal display 28 corresponding to display means is fixed to the front of the operation panel 24. As shown in FIG. 3, the liquid crystal display 28 is electrically connected to an output terminal of the operation control device 27, and the operation control device 27 performs operation such as setting results of the inside temperature Tr and the inside temperature Tf. The information is displayed on the liquid crystal display 28.

An R temperature sensor 29 and an F temperature sensor 30 are electrically connected to input terminals of the operation control device 27. The R temperature sensor 29 and the F temperature sensor 30 are connected to the inside temperature of the refrigerator compartment 4 and the freezer compartment. A temperature signal Vr and a temperature signal Vf corresponding to the internal temperature of 14 are output to the operation control device 27.

An output terminal of the operation control device 27 is electrically connected to the compressor 20, the valve 21, the R fan device 22, and the F fan device 23. The operation control device 27 outputs the temperature signals Vr and Vf to the set temperature Tr. And Tf, compressor 20, valve 21, R fan device 2
2. Based on the drive control of the F fan device 23 according to the comparison result, the inside of the refrigerator compartment 4 and the inside of the freezer compartment 14 are kept at the set temperatures Tr and Tf.

As shown in FIG. 1, a gas sensor 31 is fixed to the ceiling in the refrigerator compartment 4. The gas sensor 31 is a semiconductor gas sensor having a high sensitivity to ammonia, and as shown in FIG.
2 input terminals. This ammonia is released from the meat and vegetables in the process of decay of the meat and vegetables, and the gas sensor 31 outputs an analog concentration signal S1 at a level corresponding to the gas concentration in the refrigerator compartment 4. The output circuit 32 is connected to the cabinet 1
And the analog density signal S1
, And converts the analog density signal S1 into a digital density signal S1 '.

In the cabinet 1, a food management device 33 (see FIG. 3) mainly composed of a microcomputer is provided, and an input terminal of the food management device 33 has an output terminal as shown in FIG. An output terminal of the circuit 32 is electrically connected, and an output terminal of the food management device 33 is electrically connected to an input terminal of the operation control device 27. The food management device 33 corresponds to freshness determination means, and processes the density signal S1 'from the output circuit 32 in the following procedure.
The following operation is executed by the food management device 33 based on a control program recorded in the ROM in advance.

<Processing Procedure of Density Signal S1 '> When the power of the food management apparatus 33 is turned on, the flag F1 is set to "0" in step S1 of FIG. 2A, and the process proceeds to step S2. . Then, based on the concentration signal S1 'output from the output circuit 32, the gas concentration p1 is detected, and the routine proceeds to step S3.

When the process proceeds to step S3, the food management device 33 detects the gas amount f1 based on the substitution of the gas concentration p1 in step S2 into the equation (1), and then proceeds to step S4. f1 = α1 × p1 × V (1) where α1 is a gas constant determined by the type of gas, and V is the volume of the refrigerator compartment 4.

When the process goes to step S4, the food management device 33 determines the state of the flag F1. Here, "F1 =
Since it is "0", the process proceeds to step S5, and the set value Y1up is set to the determination value Y. Then, the process proceeds to step S7, where the gas amount f1 in step S3 is compared with the determination value Y1up.

If the food management device 33 detects "gas amount f1≤judgment value Y1up" in step S7, it sets "0" to the flag F1 in step S8, and determines "no rot" in step S9. Further, in step S7, the "gas amount f1
When the "determination value Y1up" is detected, "1" is set to the flag F1 in step S10. Then, step S11
To determine that there is decay, and outputs a freshness determination result to the operation control device 27 in step S12. Then, the operation control device 27 displays "Food is spoiled" on the liquid crystal display 28.
Is displayed to inform the user of the spoilage of the food.

The food management apparatus 33 proceeds from step S4 to S6 when the flag F1 is set. Then, the set value Y1down is set to the determination value Y, and the gas amount f1 is compared with the determination value Y1down in step S7. For this reason, as shown in FIG. 2B, when determining that there is no decay, the gas amount f1 is determined.
Is compared with the determination value Y1up, and when it is determined that there is decay, the gas amount f1 is compared with the determination value Y1down.
Hysteresis is formed between p and Y1down to prevent a small change in the gas concentration p1 from changing the determination result of freshness.

According to the first embodiment, the gas sensor 31
The freshness of the food was determined on the basis of the density signal S1 from the LCD, and the determination result was displayed on the liquid crystal display 28. This eliminates the need for the user to perform a troublesome operation of inputting the type of food and the expiration date, and the freshness of the food can be easily managed only by checking the display content of the liquid crystal display 28.

Further, a gas sensor 31 for ammonia is provided on the ceiling in the refrigerator compartment 4. Therefore, even when the amount of food in the refrigerator compartment 4 is large and the cold air does not circulate to every corner in the refrigerator compartment 4, the ammonia gas has a specific gravity (the ammonia gas has a lower specific gravity than the air) and concentrates on the gas sensor 31 on the ceiling. Therefore, the presence or absence of spoilage of the food is accurately determined.

Next, a second embodiment of the present invention will be described with reference to FIG. When the power is turned on, the food management device 33 sets “0” to the flags Fa and Fb in step S21 of FIG. 5A, and proceeds to step S22. Then, the gas concentration p1 is detected based on the concentration signal S1 ',
Move to step S23.

When the process proceeds to step S23, the food management device 33 detects the gas amount f1 based on the substitution of the gas concentration p1 into the above equation (1), and determines the state of the flag Fa in step S24. Here, since “Fa = 0”, the process proceeds to step S25 and the determination value Y is set to the set value Yaup.
Is set. Then, the flow shifts to step S27, where the gas amount f1 is compared with the determination value Yaup.

When the food management device 33 detects "gas amount f1≤judgment value Yaup" in step S27, the process proceeds to step S2.
At step 8, the flag Fa is set to "0". Then, in step S29, it is determined that the freshness is good, and in step S30
Outputs the determination result to the operation control device 27. Then, the operation control device 27 displays a cautionary message on the liquid crystal display 28, "Is the freshness of the food reduced?"

When the food management device 33 detects "gas amount f1> judgment value Yaup" in step S27, it proceeds to step S3.
At step 1, the flag Fa is set to "1", and at step S32, the state of the flag Fb is determined. Here, since “Fb = 0”, the process proceeds to step S33 to set the set value Ybup as the determination value Y. Then, the flow shifts to step S35, where the gas amount f1 is compared with the judgment value Ybup.

When the food management device 33 detects "gas amount f1≤judgment value Ybup" in step S35, the process proceeds to step S3.
In step 6, "0" is set in the flag Fb. Then, it is determined in step S37 that the freshness of the food has decreased, and a determination result is output to the operation control device 27 in step S38. Then, the operation control device 27 displays a definite message on the liquid crystal display 28 that “the freshness of the food is low”.

When the food management device 33 detects "gas amount f1> set value Ybup" in step S35, the process proceeds to step S3.
In step 9, "1" is set in the flag Fb. Then, in step S40, it is determined that the food is spoiled, and in step S4
In step 1, the determination result is output to the operation control device 27. Then
The operation control device 27 displays a warning message on the liquid crystal display 28, "Is the food spoiled?"

The food management device 33 proceeds from step S24 to S26 when the flag Fa is set. Then, the set value Yadown is set to the judgment value Y, and the gas amount f1 is compared with the judgment value Yadown in step S27. Therefore, as shown in FIG. 5B, the determination values Yaup and Yadown
A hysteresis is formed between them, thereby preventing a small change in the gas concentration p1 from changing the determination result of freshness.

When the flag Fb is set, the food management device 33 proceeds from step S32 to S34 in FIG. Then, the set value Ybdown is set to the judgment value Y, and the gas amount f1 is compared with the judgment value Ybdown in step S35. For this reason, as shown in FIG.
Hysteresis is formed between p and Ybdown to prevent a small change in the gas concentration p1 from changing the determination result of freshness.

According to the second embodiment, the gas sensor 31
The freshness of the food was classified into three levels on the basis of the density signal S1. For this reason, the freshness of the food is a cautionary level of "Is freshness reduced?", A definitive level of "freshness is decreasing", and a warning level of "decaying". Since it can be displayed, it becomes easy for the user to treat the food, such as eating or discarding the food early.

In the second embodiment, the freshness of the food is classified into three levels based on the density signal S1 from the gas sensor 31, but the present invention is not limited to this. For example, the freshness is classified into four or more levels. Is also good.

Further, in the second embodiment, the freshness of the food is displayed as a message on the liquid crystal display 28, but the present invention is not limited to this. For example, a numerical value may be displayed. In this case, the numerical value may be increased as the freshness of the food decreases, and the maximum value may be displayed when the food rots.

In the second embodiment, the freshness of the food is displayed as a message on the liquid crystal display 28. However, the present invention is not limited to this. For example, a plurality of LEDs arranged in one direction are sequentially lit. May be displayed. In this case, it is preferable to increase the number of lighted LEDs as the freshness of the food decreases, and to light all the LEDs when the food rots.

In the first and second embodiments, the gas sensor 3 for ammonia is provided on the ceiling in the refrigerator compartment 4.
1 is mounted, but the present invention is not limited to this, and for example, the following configuration may be adopted. A semiconductor gas sensor for methane is mounted on the ceiling in the refrigerator compartment 4. In this case, even when the amount of food in the refrigerator compartment 4 is large and the cold air does not circulate to every corner in the refrigerator compartment 4, the methane gas released from the food in the process of spoiling the food has a specific gravity (the specific gravity of methane gas is higher than that of air). Light) and concentrates on the gas sensor on the ceiling, so that the freshness of the food is accurately determined. A semiconductor gas sensor for carbon dioxide is mounted on the bottom of the refrigerator compartment 4. In this case, even when the amount of food in the refrigerator compartment 4 is large and cold air does not circulate to every corner in the refrigerator compartment 4, the carbon dioxide gas released from the food in the process of spoiling the food has a specific gravity (carbon dioxide gas). (The specific gravity of which is greater than air) concentrates on the bottom gas sensor, so that the freshness of the food is accurately determined.

In the first and second embodiments, the gas sensor 31 for ammonia is mounted in the refrigerator compartment 4. However, the present invention is not limited to this. A gas sensor 31 for carbon dioxide, or a gas sensor for carbon dioxide at the bottom of the vegetable compartment 7.

Next, a third embodiment of the present invention will be described with reference to FIG. Gas sensors 31 are mounted in the refrigerator compartment 4 at the ceiling, bottom, left side, and right side. Each of these gas sensors 31 is electrically connected to an input terminal of a food management device 33 via an output circuit 32, and the food management device 33 is connected to the four output circuits 3 by the four gas sensors 31.
The four gas amounts f1 are detected based on the four concentration signals S1 'given through the line 2.

When the food management device 33 detects the four gas volumes f1, the food management device 33 performs a decay determination operation on the largest one of the four gas volumes f1. Output a signal. At the same time, the location of the food spoilage is determined based on where the gas sensor 31 having the maximum gas amount is installed, and the determination result is output to the operation control device 27.

For example, when the decay level concentration signal S 1 is output from the ceiling gas sensor 31, it is determined that the decay location of the food is the ceiling in the refrigerator compartment 4, and the decay level concentration signal is output from the bottom gas sensor 31. When S1 is output, it is determined that the place where food is spoiled is the bottom of the refrigerator compartment 4. When the decay level concentration signal S1 is output from the gas sensor 31 on the left side, it is determined that the decay place of the food is the left side in the refrigerator compartment 4,
The decay level concentration signal S1 from the gas sensor 31 on the right side
Is output, it is determined that the putrefying place of the food is the right side in the refrigerator compartment 4.

When the operation control device 27 detects the output signal from the food management device 33, the operation control device 27 sets the decay information and displays it on the liquid crystal display 28. This rotting information indicates where in the refrigerator compartment 4 the food is rotten, and the liquid crystal display 2
8, a message corresponding to the corruption information is displayed.

For example, when food is rotten on the ceiling in the refrigerator compartment 4, a message “Food is rotten on the ceiling of the refrigerator compartment” is displayed, and the food is rotten on the bottom in the refrigerator compartment 4. The message "Food is spoiled at the bottom of the refrigerator compartment" is displayed. Also,
When the food is spoiled on the left side of the refrigerator compartment 4, a message “Food is spoiled on the left side of the refrigerator compartment” is displayed, and when the food is spoiled on the right side of the refrigerator compartment 4. "Food is spoiled on the right side of the refrigerator"
Message is displayed.

According to the third embodiment, a plurality of gas sensors 31 for the same kind of gas are arranged at different places in the refrigerator compartment 4. Then, based on the concentration signals S1 from the plurality of gas sensors 31, the storage location of the food whose freshness is decreasing is determined,
The display shows where the food whose freshness is decreasing is stored in the refrigerator compartment 4. This makes it easier for the user to search for foods whose freshness is decreasing, and thus facilitates processing of the foods such as eating or discarding the foods whose freshness is decreasing.

In the third embodiment, the decay judgment operation and the decay place judgment operation are performed for the gas sensor having the largest gas amount among the four gas sensors 31, but the present invention is not limited to this. , For example, four gas sensors 31
The determination operation of the rot and the determination operation of the rot place may be individually performed, and the results may be displayed on the liquid crystal display 28.

In the third embodiment, the plurality of gas sensors 31 are mounted at different places in the refrigerator compartment 4. However, the present invention is not limited to this. For example, the gas sensors 31 are mounted at different places in the vegetable compartment 7. May be.

In the third embodiment, the gas sensor 31 for ammonia is used. However, the present invention is not limited to this. For example, a gas sensor for carbon dioxide, a gas sensor for amine, a gas sensor for ethylene, and the like may be used. May be used. In short, any gas sensor that outputs an electric signal according to the concentration of gas released from the food in the process of spoiling the food may be used.

Next, a fourth embodiment of the present invention will be described with reference to FIGS.
It will be described based on. As shown in FIG. 7, a gas sensor 31 is mounted in the refrigerator compartment 4 at the ceiling. As described above, the gas sensor 31 is a semiconductor gas sensor having high sensitivity to ammonia, and is electrically connected to the input terminal of the food management device 33 via the output circuit 32.

As described above, ammonia is emitted from meat and vegetables in the process of decay of meat and vegetables, and the food management device 33 outputs the concentration signal S 1 output from the gas sensor 31 through the output circuit 32. , The gas amount f1 is detected. Then, the gas amount f1 is compared with the determination value Y1m for meat and the determination value Y1v for vegetables, and as shown below, the ammonia gas concentration for vegetables and the ammonia gas concentration for vegetables are determined based on the comparison result. The magnitude of the density is determined.

"Gas amount f1≤judgment value Y1m" ... Small ammonia gas concentration in meat "Gas amount f1> Judgment value Y1m" ... High ammonia gas concentration in meat "Gas amount f1≤judgment value Y1v" ... Vegetables Small ammonia gas concentration "gas amount f1> judgment value Y1v" ... large ammonia gas concentration in vegetables

When determining that the gas concentration is low, the set values Y1mup and Y1vup are set in the determination value Y1m, as shown in FIGS. 8A and 8B, and the gas amount f1 is changed to the determination values Y1mup and Y1vup. Be compared. When the gas concentration is high, the set value Y1mdown and Y1vdown
Is set, and the gas amount f1 is determined by the determination values Y1mdown and Y1v.
Compared with down.

As shown in FIG. 7, a gas sensor 34 is mounted on the ceiling of the refrigerator compartment 4. The gas sensor 34 is composed of a semiconductor gas sensor having high sensitivity to amine, and is electrically connected to an input terminal of the food management device 33 via the output circuit 32.

Amine is released from meat during the process of spoiling the meat.
4 through the output circuit 32.
, The gas amount f2 is detected. And the gas amount f2
Is compared with a determination value Y2m, and as described below, the magnitude of the amine gas concentration is determined based on the comparison result. "Gas amount f2 ≤ judgment value Y2m" ... amine gas concentration is low "Gas amount f2> judgment value Y2m" ... amine gas concentration is large

When the gas concentration is low, the set value Y2mup is set to the determination value Y2m and the gas amount f2 is compared with the determination value Y2mup, as shown in FIG. 8C. When the gas concentration is high, the set value Y2mdo
wn is set, and the gas amount f2 is compared with the judgment value Y2mdown.

As shown in FIG. 7, a gas sensor 35 is mounted in the refrigerator compartment 4 at the ceiling. The gas sensor 35 is composed of a semiconductor gas sensor having high sensitivity to ethylene, and is electrically connected to an input terminal of the food management device 33 via an output circuit 32.

Ethylene is released from the vegetables during the process of decay of the vegetables, and the food management device 33 detects the gas amount f3 based on the concentration signal S3 'output from the gas sensor 35 through the output circuit 32. . Then, the gas amount f3 is compared with a judgment value Y3v, and as shown below, the magnitude of the ethylene gas concentration is judged based on the comparison result. "Gas amount f3? Judgment value Y3v" ... ethylene gas concentration low "Gas amount f3> judgment value Y3v" ... ethylene gas concentration high

When determining that the gas concentration is low, the set value Y3vup is set to the determination value Y3v and the gas amount f3 is compared with the determination value Y3vup, as shown in FIG. 8D. When the gas concentration is high, the set value Y3vdo is set to the judgment value Y3v.
wn is set, and the gas amount f3 is compared with the judgment value Y3vdown.

[0061] The food management device 33 has an ammonia gas concentration
When the magnitude of the ethylene gas concentration is determined, if both the ammonia gas concentration and the amine gas concentration for the meat are high, it is determined that the meat has been spoiled, and a meat spoilage detection signal is output to the operation control device 27. Then, the operation control device 2
7 displays on the liquid crystal display 28 a message that "meat is spoiled."

When both the ammonia gas concentration and the ethylene gas concentration for vegetables are high, the food management device 33 determines that the vegetables are putrefying and outputs a putrefaction detection signal of the vegetables to the operation control device 27. . Then, the operation control device 27 displays a message “Vegetables are putrefying” on the liquid crystal display 28.

According to the fourth embodiment, the gas sensors 31, 34, 35 for different kinds of gases are mounted on the same part in the refrigerator compartment 4. Then, based on the density signals S1, S2, S3 from the gas sensors 31, 34, 35, the type of the food whose freshness is decreasing is determined, and what the food whose freshness is decreasing is displayed. This makes it easier for the user to search for foods whose freshness is decreasing, and thus facilitates processing of the foods such as eating or discarding the foods whose freshness is decreasing.

In the fourth embodiment, a gas sensor having high sensitivity to methane gas may be mounted instead of the gas sensor 34. The methane gas is released from the meat during the process of meat decay, and it is preferable to determine that the meat has rot when the detection results of both the ammonia gas sensor 31 and the methane gas sensor are high.

In the fourth embodiment, a gas sensor having high sensitivity to carbon dioxide gas or a gas sensor having high sensitivity to methyl sulfide gas may be mounted instead of the gas sensor 35. These carbon dioxide gas and methyl sulfide gas are released from the vegetables during the process of decay of the vegetables. If the detection results of both the gas sensor 31 for ammonia and the gas sensor for carbon dioxide have a high concentration, the It is good to judge that there is decay of vegetables, or when the detection results of both the gas sensor 31 for ammonia and the gas sensor for methyl sulfide have high concentrations.

In the fourth embodiment, the decay of meat and the decay of vegetables are determined. However, the present invention is not limited to this. For example, the rot of eggs may be determined.
In this case, a gas sensor having a high sensitivity to hydrogen sulfide and a gas sensor having a high sensitivity to amines released from the eggs in the process of decay of the eggs are attached to the same part in the refrigerator compartment 4 and the output signals from both gas sensors are high. If it is the concentration, it is good to judge that there is putrefaction of eggs.

In the first to fourth embodiments, the determination values Y1up, Y1down and the like are fixed. However, the present invention is not limited to this. For example, when the R door 5 is opened, the outside of the refrigerator compartment 4 is opened. The determination values Y1up, Y1down, etc. may be corrected according to the opening time of the R door 5 in consideration of the influence of the amount of gas released.

Further, in the first to fourth embodiments, the liquid crystal display 28 is mounted on the front surface of the R door 5, but the present invention is not limited to this. The determination result may be displayed on an LED display.

In the first to fourth embodiments, the dedicated food management device 33 for judging the freshness of food based on the output signal from the gas sensor 31 or the like is provided. However, the present invention is not limited to this. No, for example, the operation control device 27
May determine the freshness of food based on an output signal from the gas sensor 31 or the like.

In the first to fourth embodiments, a semiconductor gas sensor is used as the gas sensor 31 or the like. However, the present invention is not limited to this. For example, a contact combustion type gas sensor may be used.

In the first to fourth embodiments, the present invention is applied to a refrigerator having a configuration in which the refrigerator compartment 4 and the freezer compartment 14 are cooled by dedicated R evaporators 18 and F evaporators 19, but the present invention is not limited to this. However, the present invention may be applied to a refrigerator configured to cool the refrigerator compartment 4 and the freezer compartment 14 by a common evaporator.

[0072]

As is apparent from the above description, the refrigerator of the present invention has the following effects. According to the first aspect of the invention, the freshness of the food is determined based on the output signal from the gas sensor, and the determination result is displayed on the display means, so that the user can easily manage the freshness of the food without trouble. According to the second aspect of the invention, the freshness of the food is distinguished and determined in three or more stages, and the freshness of the food is displayed in the three or more stages, thereby facilitating the processing of the food.

According to the third aspect of the present invention, a gas sensor for detecting a gas having a specific gravity higher than that of air or a gas lighter than air is provided at the bottom or the ceiling of the storage chamber. Therefore, the gas released from the food concentrates on the gas sensor at the bottom or the gas sensor at the ceiling, so that the freshness of the food is accurately determined. According to the fourth aspect of the present invention, the storage location of the food whose freshness is decreasing is estimated and the estimation result is displayed, so that it is easy to search for the food whose freshness is decreasing. According to the means of claim 5, since the type of the food whose freshness is decreasing is estimated and the estimation result is displayed, it is easy to search for the food whose freshness is decreasing.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention (a perspective view showing the appearance of a refrigerator).

FIG. 2A is a flowchart showing the control content of the food management apparatus, and FIG. 2B is a diagram showing the principle of determining freshness;

FIG. 3 is a block diagram showing an electrical configuration.

FIG. 4 is a sectional view taken along the line X in FIG. 1;

FIG. 5 is a diagram showing a second embodiment of the present invention (a is a flowchart showing the control contents of the food management apparatus, and b is a diagram showing the principle of judging freshness).

FIG. 6 is a view corresponding to FIG. 1 showing a third embodiment of the present invention.

FIG. 7 is a view corresponding to FIG. 1, showing a fourth embodiment of the present invention.

8A is a diagram illustrating a principle of determining the ammonia gas concentration for meat, FIG. 8B is a diagram illustrating a principle of determining the ammonia gas concentration for vegetables, and FIG. 8C is a diagram illustrating the principle of determining an amine gas concentration; FIG. 3D is a diagram showing the principle of determining the ethylene gas concentration.

[Explanation of symbols]

4 is a refrigerator room (storage room), 7 is a vegetable room (storage room), 28 is a liquid crystal display (display means), 31 is a gas sensor, 33 is a food management device (freshness determination means), 34 is a gas sensor, 35
Indicates a gas sensor.

Claims (5)

[Claims] 1. A storage room in which food is stored, a gas sensor provided in the storage room and outputting an electric signal according to a gas concentration released in the process of spoiling the food, and an output signal from the gas sensor. A refrigerator comprising: freshness determining means for determining freshness of food; and display means for displaying a determination result of the freshness determining means. 2. The freshness determining means distinguishes food freshness in three or more levels based on an output signal from the gas sensor, and the display means displays food freshness in three or more levels. The refrigerator according to claim 1, wherein 3. The refrigerator according to claim 1, wherein a gas sensor for detecting a gas whose specific gravity is heavier or lighter than air is provided at a bottom or a ceiling in the storage room. 4. A storage room, wherein a plurality of gas sensors for the same type of gas are provided at different portions, and the freshness judging means detects the food whose freshness is decreasing based on output signals from the plurality of gas sensors. The refrigerator according to claim 1, wherein the storage location is determined, and the display unit displays a storage location of the food item whose freshness is decreasing. 5. A storage room, wherein a plurality of gas sensors for different types of gas are provided at the same portion, and the freshness judging means detects the food whose freshness is decreasing based on output signals from the plurality of gas sensors. The refrigerator according to claim 1, wherein the type is determined, and the type of the food whose freshness is decreasing is displayed on the display means.