JP3098780B2 - Refrigerator refrigerator control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a control rule based on an empirical rule and a membership function of a fuzzy variable constituting the rule in order to store frozen food in a freezer with freshness for a long period of time. The present invention relates to a refrigerator-freezer control device that infers an operation amount of a fan motor and an operation amount of a compressor and outputs the result.

[0002]

2. Description of the Related Art A refrigerator-freezer control device is provided with a fan motor, a compressor, and a compressor so as to control the temperature of each of a freezer compartment, a refrigerator compartment, and a vegetable compartment of a refrigerator-freezer (hereinafter abbreviated as a refrigerator) at a set temperature. It controls the electric damper.
In the freezer compartment, various foods that can be stored for a long time by freezing food have been proposed (for example, NR-F40VP1 manufactured by Matsushita Electric Industrial Co., Ltd., released in May 1990).

[0003] In the following, the control of the temperature of a freezer compartment will be described in particular with reference to the drawings of a conventional control device for a refrigerator.

FIG. 6 is a block diagram showing a conventional control device for a refrigerator. In FIG. 6, reference numeral 1 denotes a refrigerator main body, which is composed of an outer box 2 and an inner box 3 and a urethane foam heat insulating material 4 formed in a gap between the two boxes, and three doors 5, 6, 7 are disposed in a front opening. ing. Doors 5, 6, and 7 are a freezer compartment 8, a refrigerator compartment 9, and a vegetable compartment 10 of the refrigerator body 1, respectively.
Are arranged corresponding to the openings.

[0005] The bottom plate 11 of the freezer compartment 8 and the top plate 12 of the refrigerator compartment 9
The evaporator 13 and a fan 14 are provided behind the evaporator 13 in the partition wall surrounded by. Further, ventilation paths 15 and 16 for introducing cooling air from the evaporator 13 into each chamber are formed at the back of the freezing chamber 8 and the refrigerator compartment 9. 17 is a compressor. Reference numeral 18 denotes a freezer compartment door switch that operates by opening and closing the door 5 of the freezer compartment 8, and 19 denotes a freezer compartment temperature sensor. 21 is a fan motor for driving the fan 14.

Reference numeral 22 denotes door opening / closing detecting means for detecting the opening / closing of the door 5 of the freezing room 8 based on the operation of the freezing room door switch 18. This is a refrigerator temperature detecting means. 33
Is an operation means for obtaining the operation amount of the fan motor and the operation amount of the compressor from the internal temperature detected by the internal temperature detecting means 25.

Reference numeral 31 denotes fan motor control means for controlling the fan motor 21 based on the operation amount of the fan motor to drive the fan 14, and reference numeral 32 denotes compressor control means for driving the compressor 17 based on the operation amount of the compressor.

The operation of the control device for a refrigerator-freezer constructed as described above will be described below with reference to FIGS.

FIG. 7 is a flow chart for explaining the conventional temperature control of the freezing compartment 8. First, the door opening / closing detecting means 22 detects the operation of the freezer compartment door switch 18 from the operation of the freezer compartment switch 18.
It is determined whether or not the door 5 is closed (S
step21). If the door 5 is closed, the freezer temperature detecting means 25 detects the freezer compartment temperature Tfc by the freezer compartment temperature sensor 19 (Step 22). Then, the calculating means 33 calculates the operation amount m of the fan motor based on the internal temperature Tfc.
And the operation amount f of the compressor (Step 2)
3).

The fan motor control means 31 drives the fan 14 by controlling the fan motor 21 based on the operation amount m of the fan motor, and the compressor control means 32 controls the compressor 14 based on the operation amount f of the compressor. 17 is driven (Step 24). From the above, freezer 8
A suitable temperature of cold air is supplied to the freezer to control the temperature of the freezer compartment. If the door 5 is open, the fan 14 and the compressor 17 are stopped (Step 25).

[0011]

However, in the above configuration, the control amount m of the fan motor and the control amount f of the compressor are calculated based on only the information on the inside temperature Tfc detected by the inside temperature detecting means 25. However, there is a problem in that it is not possible to perform a fine temperature control, for example, in the summer season, when food is packed or when a sudden visitor wants to cool down quickly, the optimum temperature control cannot be performed. Was.

The present invention solves the above problems,
By calculating the heat load (hereinafter abbreviated as load) and the heat load fluctuation (hereinafter abbreviated as load fluctuation) of the food in the freezer compartment, and the manipulated variable according to the change in the ambient temperature in the refrigerator,
An object of the present invention is to provide a control device for a refrigerator-freezer capable of performing fine temperature control.

[0013]

According to the present invention, there is provided a refrigerator-freezer control apparatus according to the present invention, comprising: a refrigerator having a freezer compartment capable of freezing and storing food.
A freezer compartment door switch that operates by opening and closing the freezer compartment door; a door open / close detector that detects opening and closing of the freezer compartment door from the operation of the freezer compartment door switch; Door opening time calculation means for calculating a door opening time by an output signal, an outside air temperature sensor provided outside the refrigerator, and an outside air temperature detection means for detecting the outside air temperature outside the refrigerator by the outside air temperature sensor, A freezer compartment temperature sensor provided in the freezer compartment, a compartment temperature detecting means for detecting the compartment temperature in the freezer compartment by the freezer compartment temperature sensor, a door opening time calculated by the door opening time calculating means, The degree of change in the ambient temperature of the freezer compartment is calculated from the outside air temperature detected by the outside air temperature detecting means and the inside temperature detected by the inside temperature detecting means. Means for calculating the ambient temperature, differentiating means for calculating the rate of change of the internal temperature based on the output of the internal temperature detecting means, and the internal temperature detected by the internal temperature detecting means and the internal quantity determined by the differentiating means. Calculates the heat load of food in the freezer compartment from the rate of change of the internal temperature and calculates the heat load by calculating the heat load fluctuation, and empirical rules for calculating the operation amount of the fan motor and the compressor. A memory for storing a control rule based on the heat load, a heat load amount calculated by the heat load calculating means, a change in heat load, and a degree of change in the ambient temperature of the freezer compartment calculated by the calculating means for the atmospheric temperature. A fuzzy inference processor for performing a fuzzy logic operation based on the set control rules to calculate an operation amount of the fan motor and an operation amount of the compressor; And an operation amount and the compressor operation amount of the calculated fan motor by Tsu support, and fan motor control means for controlling the fan motor,
And a compressor control means for driving the compressor.

[0014]

According to the present invention, the load amount and the load variation calculated by the calculating means for the thermal load (hereinafter abbreviated as load) and the degree of change in the ambient temperature of the freezer compartment calculated by the calculating means for the ambient temperature are calculated. Based on the control rules retrieved from the memory, a fuzzy logic operation is performed by a fuzzy inference processor to obtain the operation amount of the fan motor and the operation amount of the compressor. Therefore, the fan is driven by controlling the fan motor based on the operation amount obtained as described above, and the compressor is driven. Therefore, the temperature of the freezer compartment can be optimally controlled.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a control device for a refrigerator according to an embodiment of the present invention.

FIG. 1 is a block diagram of a control device of a refrigerator according to an embodiment of the present invention. FIG. 2A is a graph showing a membership function of a fuzzy variable with respect to a load in the embodiment of the present invention. ) Is a graph showing the membership function of the fuzzy variable with respect to the load change in the embodiment of the present invention, FIG. 2C is a graph showing the membership function of the fuzzy variable with respect to the degree of change in the ambient temperature in the embodiment of the present invention, and FIG. FIG. 4 is a flowchart for explaining the operation in the embodiment of the present invention, FIG. 4 is a graph showing the relationship between the door opening and closing time and the ambient temperature in the embodiment of the present invention, and FIG. It is a flowchart for explaining.

In FIG. 1, reference numeral 23 denotes a door open time calculating means, which calculates a door open time based on a signal output from the door open / close detecting means 22. Reference numeral 24 denotes an outside air temperature detecting means for detecting the outside air temperature outside the refrigerator by the outside air temperature sensor 20. Numeral 26 denotes an atmospheric temperature calculating means. The door opening time calculated by the door opening time calculating means 23, the outside air temperature detected by the outside air temperature detecting means 24, and the inside temperature detected by the inside temperature detecting means 25. The degree of change in the ambient temperature of the freezing room is calculated from the temperature.

Reference numeral 27 denotes a differentiating means for differentiating the output from the internal temperature detecting means 25 to obtain a rate of change of the internal temperature.
Numeral 28 is a load calculating means. The load amount of food in the freezer compartment (food temperature × heat capacity) is calculated based on the internal temperature detected by the internal temperature detecting means 25 and the rate of change of the internal temperature obtained by the differentiating means 27. ) Is calculated, and the load variation (increase / decrease of the load amount) is further calculated. Reference numeral 29 denotes a memory which stores a control rule based on an empirical rule for obtaining the operation amount of the fan motor and the operation amount of the compressor.

Reference numeral 30 denotes a fuzzy inference processor, which is fetched from the memory 29, the load amount and the load fluctuation calculated by the load calculating means 28, the degree of change in the ambient temperature of the freezer calculated by the atmospheric temperature calculating means 26, and the like. A fuzzy logic operation is performed based on the set control rules to calculate the operation amount of the fan motor and the operation amount of the compressor.

The operation of the refrigerator-freezer control device configured as described above will be described below with reference to FIGS.

First, the door opening / closing detecting means 22 determines from the operation of the freezer compartment door switch 18 whether or not the door 5 of the freezer compartment 8 is closed (Step 1). If the door 5 is closed, the outside air temperature is determined. The detecting means 24 detects the outside air temperature Tout outside the refrigerator by the outside air temperature sensor 20 (S
tep2), the inside temperature detection unit 25 detects the inside temperature Tfc ₀ of the freezing chamber by the freezing compartment temperature sensor 19 (St
ep3).

When the door 5 is opened, the door opening time calculating means 23 starts a timer counter in the door opening time calculating means 23 to calculate the door opening time based on the signal from the door opening / closing detecting means 22. (Step
4) Stop the fan 14 and the compressor 17 (St)
ep5). At this time, food is taken in and out of the freezing room 8, and outside air flows into the room (Step 6).

Next, when the door 5 is closed (Step
7) The door opening time calculation means 23 stops the timer counter (Step 8), and calculates the door opening time H from this timer counter (Step 9). Then, the atmospheric temperature calculating means 26 calculates the door opening time H calculated by the door opening time calculating means 23 and the outside air temperature detecting means 24.
And outside air temperature Tout detected by, for calculating the ambient temperature change degree D of the freezing chamber from the detected inside temperature Tfc ₀ Metropolitan by the internal temperature detector 25 (Step10).

Here, the relationship between the door opening time and the ambient temperature is a characteristic curve as shown in FIG. 4. As the door opening time increases, the ambient temperature also increases, and the ambient temperature change D is

[0025]

(Equation 1)

[0026] Further, the freezer temperature detecting means 25 detects the freezer compartment temperature Tfc in the freezer compartment by the freezer compartment temperature sensor 19 (Step 11), and the differentiating means 27 outputs the output from the freezer temperature detecting means 25 as shown in (Equation 2). Is differentiated to obtain a change rate ΔTfc of the internal temperature (Step
12).

[0027]

(Equation 2)

Then, the load calculating means 28 calculates the load of the food in the freezer compartment from the internal temperature Tfc detected by the internal temperature detecting means 25 and the rate of change ΔTfc of the internal temperature obtained by the differentiating means 27. The amount W is calculated (Step 13), and the load variation V is calculated as shown in (Equation 3) (St
ep14).

[0029]

(Equation 3)

Next, the calculated load amount W and load fluctuation V
The ambient temperature change degree D is input to the fuzzy inference processor 30 (Step 15). The fuzzy inference processor 30 takes out the control rules stored in the memory 29 in advance and calculates the operation amount m of the fan motor and the operation amount f of the compressor by fuzzy inference (S).
step16). The fan motor control means 31 drives the fan 14 by controlling the fan motor 21 based on the operation amount m of the fan motor, and the compressor control means 32 drives the compressor 17 based on the operation amount f of the compressor. (Step 17).

Here, the fuzzy inference for obtaining the operation amount of the fan motor and the operation amount of the compressor for optimally controlling the temperature of the freezing room is executed based on the following control rules.

The control rules employed in this embodiment are the following 27 rules. For example, rule 1: If the load is large, the load increases, and the degree of change in the ambient temperature is large, the rotation of the fan motor is increased and the compressor is turned on. Rule 2: If the load is normal, the load does not fluctuate, and the ambient temperature change is normal, the rotation of the fan motor is reduced and the compressor is turned on. Rule 3: If the load is small, the load is reduced, and the degree of change in the ambient temperature is small, the rotation of the fan motor is turned off.
And turn off the compressor.

And so on.

This is a rule obtained from the experience that if the load amount is large or the degree of change in the ambient temperature is large, rapid cooling is required and the rotation of the fan motor must be accelerated. Therefore, the above language rules are control rules for the amount of operation of the fan motor and the amount of operation of the compressor, which can perform optimal temperature control of the freezer compartment, obtained from the numerous experimental data by the inventor. Table 1 shows the relationship between the load fluctuation and the degree of ambient temperature change.

[0035]

[Table 1]

(Table 1) is a table showing the relationship between the control rules. The load W is determined in three stages in the horizontal direction (LW = many, MW = medium,
SW = small), the load fluctuation V is divided into three stages (IV = increase, NV = none, DV = decrease), and the ambient temperature change degree D is vertically divided into three stages (LD = large, MD = medium, SD = small). ), And the positions where the above-mentioned divided load amount W, load change V and ambient temperature change D intersect correspond to the load amount W, load change V and ambient temperature change D, respectively. Optimal fan motor operation amount and compressor operation amount are arranged.

The above language rules are stored in the memory 29 of FIG.
Is stored according to the following rule. The number of control rules adopted in this embodiment is 27. .., The control rule 1, the rule 2,..., The rule of the rule 27 are: load W, load fluctuation V, ambient temperature change D, fan motor operation M, compressor operation F
Is determined stepwise as shown in (Table 1), and when fine control is performed, the actually measured load w in the middle of each of the load W, the load fluctuation V, and the ambient temperature change D is determined. , Load fluctuation v, and ambient temperature change degree d, the degree to which the antecedent part (IF section) of the control rule is satisfied is calculated, and the operation amount m of the fan motor and the compressor It is necessary to estimate the operation amount f. Therefore, in the present embodiment, the degree is calculated using a membership function of a fuzzy variable with respect to the load amount W, the load variation V, and the ambient temperature change degree D.

FIG. 2A shows a membership function μSW of the fuzzy variables SW, MW, and LW with respect to the load W.
2 (w), μMW (w), and μLW (w). FIG. 2B shows a fuzzy variable D with respect to the load variation V.
V, NV, IV membership functions μDV (v), μN
FIG. 2 shows V (v) and μIV (v).
(C) is a fuzzy variable S for the ambient temperature change D.
D, MD, LD membership functions μSD (d), μM
D (d) and μLD (d). The fuzzy inference executed by the fuzzy inference processor 30 includes the control rule 1, the rule 2,...
A fuzzy logic operation is performed using the membership functions of (b) and (c) to calculate an operation amount.

Hereinafter, the procedure of fuzzy inference which is Step 16 of FIG. 3 will be described with reference to the flowchart of FIG.

[0040] In Step 18, load w ₀ by fuzzy reasoning processor 30, by using the membership function of the fuzzy variables to the load variation v ₀ and ambient temperature gradient d _0, load w _0, a load fluctuation v ₀ and ambient temperature Degree of change d ₀
Of the membership value (represented by the M value in the figure) at the time.

In Step 19, the obtained load amount w ₀ ,
The degree to which the membership value of the fuzzy variable with respect to the load variation v ₀ and the degree of change in the ambient temperature d ₀ satisfies the antecedents of each of the 27 rules is calculated by the synthesis method as follows.

In the figure, A represents a fuzzy variable for the load amount, B represents a fuzzy variable for the load variation, and C represents a fuzzy variable for the degree of change in the ambient temperature. Rule 1: h1 = μLW (w ₀ ) ∩μIV (v ₀ ) ∩μLD (d ₀ ) = MIN {μLW (w ₀ ), μIV (v ₀ ), μLD (d ₀ )} --- (1) Rule 2: h2 = μMW (w ₀ ) ∩μNV (v ₀ ) ∩μMD (d ₀ ) = MIN ｛μMW (w ₀ ), μNV (v ₀ ), μMD (d ₀ )｝ Rule (3) : H3 = μSW (w ₀ ) ∩μDV (v ₀ ) ∩μSD (d ₀ ) = MIN {μSW (w ₀ ), μDV (v ₀ ), μSD (d ₀ )} --- (3) Equation (1) shows that w ₀ is the area L with respect to the load W
W and v ₀ is the region I for load variation V
It enters the V, and the proposition that the d ₀ enters the area LD for ambient temperature change of D, the ratio of w ₀ enters the LW, v ₀ is the rate and d ₀ entering the IV smaller of the ratio entering the LD This means that the rule is satisfied at a rate as a value, that is, the antecedent part of Rule 1 is satisfied at a rate of h1. Similarly, in the case of rules 2 and 3, which are formulas (2) and (3), it indicates that the antecedent is established at the ratio of h2 and h3, respectively.

In Step 19, the control amount of the fan motor and the control amount of the compressor at the load amount w ₀ , the load fluctuation v ₀ and the atmospheric temperature change degree d ₀ are calculated as follows by the membership function of the execution unit of the control rule. Ask. The control amount m ₀ of the fan motor and the control amount f _{0 of the} compressor are calculated using the maximum height method, which is one of the single point methods, by the ratios h1, h2,. Is calculated as follows as the value of the consequent part of the control rule having the maximum height hi. m ₀ = M (max {h1, h2,..., h27}) f ₀ = F (max {h1, h2,..., h27}) Thus, the control amount m ₀ of the fan motor and the control of the compressor The quantity f ₀ is determined.

Accordingly, in this embodiment, since the load amount, the load fluctuation, and the degree of change in the ambient temperature are used as the control parameters, fine control is possible. Also,
Since the control rules are based on human empirical rules, the temperature control of the freezing room can be controlled by the optimal operation amount of the fan motor and the operation amount of the compressor.

[0045]

As described above, the present invention relates to a freezing refrigerator provided with a freezing room capable of freezing and storing foods, wherein the freezing room door switch is operated by opening and closing the door of the freezing room; Door opening / closing detection means for detecting opening / closing of a door of a freezer compartment from operation of a switch, a door counter built-in, and a door opening time calculation means for calculating a door opening time by a signal output from the door opening / closing detection means; An outside air temperature sensor provided outside the refrigerator, an outside air temperature detecting means for detecting the outside air temperature outside the refrigerator by the outside air temperature sensor, a freezing room temperature sensor provided inside the freezing room, and freezing by the freezing room temperature sensor. A room temperature detecting means for detecting a room temperature in the room, a door opening time calculated by the door opening time calculating means, and a detection by the outside air temperature detecting means. Means for calculating an ambient temperature change degree of the freezing room from the measured outside air temperature and the inside temperature detected by the inside temperature detecting means, and the inside temperature based on the output of the inside temperature detecting means. Differentiating means for calculating the rate of change of, and calculating the heat load of food in the freezer compartment from the internal temperature detected by the internal temperature detecting means and the rate of change of the internal temperature determined by the differentiating means, Further, a heat load calculating means for calculating a heat load fluctuation, a memory for storing a control rule based on an empirical rule for obtaining an operation amount of the fan motor and an operation amount of the compressor, and a calculation means for calculating the heat load. A fuzzy logic operation is performed based on the amount of heat load, the change in heat load, the degree of change in the ambient temperature of the freezer compartment calculated by the means for calculating the ambient temperature, and the control rules retrieved from the memory. A fuzzy inference processor for calculating the operation amount of the fan motor and the operation amount of the compressor, and fan motor control means for controlling the fan motor from the operation amount of the fan motor and the operation amount of the compressor calculated by the fuzzy inference processor. By providing the compressor control means for driving the compressor, it is possible to obtain an optimal operation amount based on an empirical rule that can store frozen foods in the freezing room with freshness for a long period of time, and to finely control the temperature of the freezing room. Can be. For example, when a large amount of food is packed in summer when the outside air temperature is high, quick freezing can be performed with an operation amount according to the load of the food. In addition, since the temperature is controlled by the operation amount according to the load of the food, unnecessary energy is not consumed.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control device of a refrigerator according to an embodiment of the present invention.

2A is a graph showing a membership function of a fuzzy variable with respect to a load in the embodiment; FIG. 2B is a graph showing a membership function of a fuzzy variable with respect to a load change in the embodiment; Graph showing membership function of fuzzy variables with respect to ambient temperature change in example

FIG. 3 is a flowchart for explaining the operation in the embodiment;

FIG. 4 is a graph showing a relationship between a door opening / closing time and an ambient temperature in the embodiment.

FIG. 5 is a flowchart for explaining a procedure of fuzzy inference in the embodiment.

FIG. 6 is a block diagram of a conventional refrigerator-freezer control device.

FIG. 7 is a flowchart for explaining an operation in a conventional example.

[Explanation of symbols]

 8 Freezer compartment 18 Freezer compartment door switch 19 Freezer compartment temperature sensor 20 Outside air temperature sensor 22 Door open / close detecting means 23 Door open time calculating means 24 Outside air temperature detecting means 25 Internal temperature detecting means 26 Atmospheric temperature calculating means 27 Differentiating means 28 Load Calculation means 29 memory 30 fuzzy inference processor 31 compressor control means 32 fan motor control means

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-124574 (JP, A) JP-A-4-169768 (JP, A) JP-A-4-263771 (JP, A) JP-A-1- 225879 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25D 11/00-13/00 F25D 29/00 G05B 13/02 G05D 23/00

Claims (1)

(57) [Claims] 1. A freezing refrigerator provided with a freezing room capable of freezing and storing foods, wherein the freezing room door switch is operated by opening and closing the freezing room door, and the operation of the freezing room door switch is based on the operation of the freezing room door switch. Door opening / closing detecting means for detecting the opening / closing of the door, a timer counter, a door opening time calculating means for calculating a door opening time by a signal output from the door opening / closing detecting means, and an outside air temperature provided outside the refrigerator-freezer. A sensor, an outside air temperature detecting means for detecting an outside air temperature outside the freezer and refrigerator by the outside air temperature sensor, a freezing room temperature sensor provided in the freezing room, and a freezer room temperature detected by the freezing room temperature sensor. The inside temperature detection means, the door opening time calculated by the door opening time calculation means, the outside air temperature detected by the outside air temperature detection means, Calculating means for calculating the degree of change in the ambient temperature of the freezing room from the temperature in the refrigerator detected by the temperature detector in the refrigerator; and differentiating means for calculating the rate of change in the temperature of the refrigerator based on the output of the temperature detector in the refrigerator. And calculating the heat load (food temperature × heat capacity) of the food in the freezer compartment from the internal temperature detected by the internal temperature detecting means and the rate of change of the internal temperature determined by the differentiating means, and A heat load calculating means for calculating a heat load change (increase / decrease in heat load amount); a memory for storing a control rule based on an empirical rule for obtaining a fan motor operation amount and a compressor operation amount; Heat load calculated by the calculating means,
A fuzzy logic operation is performed on the basis of the degree of change in the ambient temperature of the freezer compartment calculated by the means for calculating the thermal load fluctuation and the ambient temperature, and the control rules retrieved from the memory, and the amount of operation of the fan motor and the amount of operation of the compressor. , A fan motor control means for controlling the fan motor based on the operation amount of the fan motor and the operation amount of the compressor calculated by the fuzzy inference processor, and a compressor control means for driving the compressor. A control device for a refrigerator-freezer, comprising: