JP2697452B2 - Refrigerator control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a refrigerator, and more particularly to an abnormality detection of a temperature detecting element or the like having a microcomputer and arranged in a refrigerator.

[0002]

2. Description of the Related Art FIGS.
FIG. 1 is a diagram showing a conventional refrigerator control device disclosed in Japanese Patent Publication No. 80, and FIG. 4 is a circuit configuration diagram showing a main part of the conventional control device. In the figure, 9g is an analog input port 10a, 1
A microcomputer (hereinafter, referred to as a microcomputer) constituting an electronic control circuit having 0b is used to convert the detection value of the temperature detecting element 4 installed in the refrigerator and the set value of the variable resistor 7a for setting the refrigerator temperature into the analog value. Input ports 10a, 10b
Read from. Reference numerals 11 and 12 denote a positive terminal (+ Vcc) and a negative terminal (GN) of a power supply for supplying a DC voltage to the microcomputer 9g and the like.
D) and 13 are voltage dividing resistors connected in series with the temperature detecting element 4 between the temperature detecting element 4 and the power supply terminal 11, and determine the voltage level applied to the temperature detecting element 4, and the signal of this voltage level is analog. The data is input from the input port 10b to the microcomputer 9g. Reference numeral 14 denotes a voltage dividing resistor connected in series with the variable resistor 7a between the variable resistor 7a and the power supply terminal 11, and determines a voltage level applied to the variable resistor 7a. From microcomputer 9g
Is input to

[0003] 7d is an output port 1 of the microcomputer 9g.
A display element such as an emitting diode connected to Oc via a current limiting resistor 15 and the other is connected to a power supply terminal 12. A relay drive circuit 9h is connected to the output port 10d of the microcomputer 9g.
This excites the relay 9i. And relay 9i
Is excited, the contact 9k is closed, the electric power from the AC power supply 9j is supplied to the compressor 8a, and the compressor 8a is driven. When the relay 9i is not energized, the contact 9k is open and the compressor 8a is stopped.

FIG. 5 shows an overall configuration of a refrigerator provided with a control device having the above circuit configuration. A temperature detecting element 4 such as the thermistor is provided in a freezing room 2a of the refrigerator 1, and an operation panel 7 having a variable resistor 7a for setting a temperature in the refrigerator and a display element 7d for displaying an abnormality is provided on a door surface. Have been. Reference numeral 9b denotes a temperature detecting means for detecting a temperature inside the refrigerator and a set temperature, to which signals from the temperature detecting element 4 and the variable resistor 7a are inputted. Reference numeral 17 denotes an internal temperature control unit that adjusts the internal temperature based on the detected internal temperature and the set temperature, and determines whether the compressor 8a is operating or stopped, and whether the temperature detection element 4 is normal or abnormal. Reference numeral 18 denotes compressor control means for controlling the driving of the compressor 8a based on the determination, and 9f denotes the display element 7d.
The abnormality display control means for controlling the turning on and off of the temperature detecting element 4 constitutes an abnormality detecting means of the temperature detecting element 4.

Next, the operation of the control device for a refrigerator having the above-described structure will be described with reference to the flow charts shown in FIGS. FIG. 6 is a schematic flowchart showing the entire control program stored in the microcomputer 9g. First, after the initial setting in step 100, the main routine is started. That is, in step 200, the microcomputer 9g reads the voltage signals input from the analog input ports 10a and 10b, converts each analog value into a digital value, and stores it. FIG. 9 shows the correlation between the digital value and the temperature (° C.). In this example, the voltage signal input from the analog input ports 10a and 10b is divided into 256 hexadecimal values of "00" to "FF", the value at -40C is "E0", and the value at + 40C is "10". "Is set.

That is, the microcomputer 9g inputs the detection value of the temperature detecting element 4 in a range from -40 ° C. to + 40 ° C., and detects the temperature in the refrigerator. Similarly, the set value (resistance value) of the variable resistor 7a is input in the same range, and the set temperature is detected.
At this time, since the temperature detecting element 4 is connected to the DC power supply (+ Vcc) via the voltage dividing resistor 13, if the temperature inside the refrigerator changes and the detection value (resistance value) of the temperature detecting element 4 changes, The voltage signal applied to the analog input port 10b of the microcomputer 9g fluctuates, and the digital value read by the microcomputer 9g fluctuates as described above. With this, the microcomputer 9
g can read the internal temperature. Variable resistor 7a
Similarly, a DC power supply (+ Vcc) is supplied via a voltage dividing resistor 14.
, The voltage signal applied to the analog input port 10a of the microcomputer 9g fluctuates and the set temperature in the refrigerator can be detected.

Next, the routine proceeds to step 700, where a temperature input is determined. Here, as shown in the detailed flowchart of FIG. 7, the magnitude of the digital value of the internal temperature and the digital value of the set temperature read by the microcomputer 9g are compared to determine whether the internal temperature is higher than the set temperature. (Step 703). If the internal temperature is higher, the compressor operation flag is set (step 705). If the internal temperature is lower, the flag is reset (step 70).
4). When the temperature input determination is completed, output setting is performed in step 800. That is, if the compressor operation flag is set, an excitation signal is output to the relay drive circuit 9h to excite the relay 9i, thereby closing the contact 9k and driving the compressor 8a. Conversely, if the compressor operation flag is reset, a non-excitation signal is output to the relay drive circuit 9h to de-energize the relay 9i. At this time, the contact 9k is open and the compressor 8a is stopped.

In the above-described operation, the inside temperature of the refrigerator is controlled to be constant. Here, the detected value (resistance value) of the temperature detecting element 4 varies depending on the temperature. The case where the digital value is “E0 or more” and the temperature is + 40 ° C. or more (the digital value is “10” or more) (including when the refrigerator is installed) is not usually considered. That is, at this time, it is considered that the temperature detection element 4 is broken or has a poor connection, and is in an abnormal state. Therefore, in step 500, the abnormality detection of the temperature detecting element 4 is performed. FIG. 8 is a detailed flowchart showing the data of the inside temperature (digital value).
Is greater than “E0” (step 30).
1) If so, output an error (step 50)
1). If the chamber temperature data is smaller than "E0", it is determined whether the data is smaller than "10" (step 30).
2) If it is smaller, an abnormal output is performed in the same manner, and at the same time, a signal is sent to the display element 7d and an abnormal display is made on the display operation panel 7.

[0009]

Since the conventional refrigerator control device is configured as described above, when the number of objects to be controlled increases or the number of display elements for performing an abnormal display increases, the microcontroller in the control device is not used. If the input / output shortage is provided by adding a microcomputer because the number of inputs and outputs of the computer will be exceeded, not only will it be expensive, but also if the display element that performs the abnormal display is stored in another place by wiring. However, there are problems that not only is the number of wirings increased and the wiring becomes expensive, but also that a highly reliable one cannot be obtained.

The present invention has been made in order to solve the above-mentioned problems, and the input / output assignment of a microcomputer in a control device can be switched between an abnormal state and a normal state. It is another object of the present invention to provide a refrigerator control device capable of reducing the number of necessary inputs and outputs of a microcomputer.

[0011]

A control device for a refrigerator according to the present invention determines whether a control target of the control device is normal or abnormal based on the detection result of the abnormality detecting means for detecting abnormality of the temperature detecting element. It has control object switching means for switching between display means.

[0012]

The control device for a refrigerator according to the present invention determines the presence or absence of an abnormality based on abnormality detection means, and switches the input / output control target of a microcomputer or the like constituting the control device by the control target switching means. In such a case, the control target is notified as an abnormality display element by the abnormality display means, and if there is no abnormality, the input / output of the control device is shared by controlling the control target that does not need to be controlled at the time of abnormality, The number of inputs and outputs is reduced.

[0013]

【Example】

Embodiment 1 FIG. An embodiment of the present invention will be described below with reference to the drawings. 1 to 3, the same reference numerals as those in the prior art denote the same or corresponding parts, and a detailed description thereof will be omitted. In FIG. 1, reference numeral 1 denotes a refrigerator main body, which comprises a freezing compartment 2a, a refrigerator compartment 2b, a chilled compartment 2c, and a vegetable compartment 2d from above. Reference numeral 3 denotes a DEF sensor which is a temperature detecting element for detecting the temperature of the cooler 2e, 4 denotes an F sensor which is a temperature detecting element for detecting the temperature in the refrigerator 2a, and 5 denotes a temperature in the refrigerator 2b. An R sensor 6, which is a temperature detecting element, and a C sensor 6, which is a temperature detecting element for detecting the temperature inside the chilled chamber 2c. 7 is an operation panel,
Reference numerals 7a, 7b, and 7c denote variable resistors for setting the temperatures of the freezing room 2a, the refrigerating room 2b, and the chilled room 2c, respectively.

Reference numeral 8 denotes an electric damper for controlling the amount of cold air flowing into the refrigerator 2b and the chilled room 2c. Reference numeral 9 denotes a control device, which determines whether or not the values of the internal temperature setting means 9a, the internal temperature detecting means 9b, the DEF sensor 3, the F sensor 4, the R sensor 5, and the C sensor 6 are within standard values. Abnormality detecting means 9c, electric damper control means 9d,
The microcomputer 9g includes a control target switching unit 9e for switching the control target of the microcomputer 9g based on the result of the determination, and a failure display unit 9f. FIG.
Is a diagram showing a main part of the circuit of one embodiment, in which 9g is a microcomputer (hereinafter referred to as a microcomputer) constituting a main part of the control device 9, and 7d is an abnormality display means 9f.
, 9h is a drive unit, 9i is a phototriac thyristor that directly drives the electric damper 8, and 9j is a commercial power supply. The resistors in the drawing (numbers not indicated) are resistors for voltage division.

Next, the operation will be described with reference to the flowchart of FIG. First, in step 100, the microcomputer 9g is initially set, and the process proceeds to step 200. In step 200, the values detected by the DEF sensor 3, the F sensor 4, the R sensor 5, and the C sensor 6 are read as input data from the temperature detecting means 9 b, and the process proceeds to step 300. In step 300, step 20
The data (digital value) X read at 0 is 10 _HEX ≤ X
If ≦ E0 _HEX , the process proceeds to step 600, and if it is out of the range, the process proceeds to step 400. In step 400, the control target determined by the initial set (step 100) is set to the light emitting diode 7d for abnormality display and the process proceeds to step 500. In step 500, the light emitting diode 7d is turned on according to the content of the abnormality.

In step 300, step 2
If the read data is normal in step 00, the process proceeds to step 600. In step 600, the control target is switched to the variable resistors 7a, 7b, 7c, the set temperature of each room is read, and the process proceeds to step 700. In step 700, the set temperature of each room is compared with the internal temperature. If the internal temperature is higher (Y in the figure), the process proceeds to step 702, and the damper flag is set in step 702 (the electric damper 8 is opened). Then, the following process for cooling the inside of the refrigerator is performed. If the inside temperature is lower in step 700 (N in the figure), the process proceeds to step 701, in which the damper flag is reset (determined that the electric damper 8 is closed) in step 701 to limit the cooling. Perform

[0017]

As described above, according to the present invention, the control target of the control device is switched between the temperature setting means and the abnormality display means depending on the presence or absence of abnormality in the internal temperature detecting element. Even if the number of objects increases, the number of inputs / outputs of microcomputers etc. constituting the control device does not increase, so there is no need to add further microcomputers etc., and the number of parts does not increase much, so it is inexpensive and highly reliable In addition, even when an abnormal display is displayed at another place using wiring, the number of wirings can be reduced, and an inexpensive and highly reliable one can be obtained.

[Brief description of the drawings]

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

FIG. 2 is a circuit diagram showing a main part of a control device according to one embodiment of the present invention.

FIG. 3 is a flowchart according to an embodiment of the present invention.

FIG. 4 is a circuit diagram showing a main part of a conventional refrigerator control device.

FIG. 5 is an overall configuration diagram of a conventional refrigerator control device.

FIG. 6 is an overall flowchart of a conventional control device.

FIG. 7 is a flowchart of a conventional temperature input determination.

FIG. 8 is a flowchart of a conventional abnormality determination.

FIG. 9 is a characteristic diagram showing a correlation between a digital value of a conventional abnormality determination and a detected temperature.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Refrigerator 3 Temperature detection element 4 Temperature detection element 5 Temperature detection element 6 Temperature detection element 8 Electric damper 8a Compressor 9 Control device 9c Abnormality detection means 9e Control object switching means 9f Abnormality display means

Claims (1)

(57) [Claims] A temperature detecting element for detecting a temperature inside the refrigerator; and an electric damper for controlling an amount of cold air flowing into the refrigerator. The electric damper and the compressor are controlled based on input data detected by the temperature detecting device. Controlling as an output, a temperature setting means for setting the temperature in the refrigerator, an abnormality detecting means for detecting an abnormality of the temperature detecting element, and an abnormality display means for displaying an abnormality detected by the abnormality detecting means. A control device for a refrigerator, comprising a control device switching means for switching a control target of the control device between the temperature setting device and the abnormality display device based on a detection result of the abnormality detection device.