JPS6373073A - Controller for freezing refrigerator - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention particularly relates to a control device for an electronically controlled refrigerator-freezer.

[Conventional technology]

FIG. 5 is a diagram showing a conventional control device for a refrigerator-freezer of this type, showing the circuit configuration of a portion that detects the internal temperature and controls the compressor. In the figure, 1 is a temperature detection element such as a thermistor that detects the temperature inside the refrigerator, and 2 is a variable resistor that sets the temperature inside the refrigerator, which are installed outside the refrigerator (outside the refrigerator-freezer body). 3 is a microcomputer constituting an electronic control circuit having analog input ports 3a and 3b;
The detected value of the temperature detection element 1 installed in the refrigerator and the set value of the variable resistor 2 for setting the temperature inside the refrigerator are read from the analog human power ports 3a and 3b.

4.5 is the positive terminal (+Vcc) and negative terminal (GND) of the power supply that supplies DC voltage to the microcomputer 3, etc.; 6
is a voltage dividing resistor connected in series with the temperature detection element 1 between the temperature detection element 1 and the power supply positive terminal 4, which determines the voltage level applied to the temperature detection element 1, and the signal of this voltage level is sent to the analog port 3a. is input to the microcomputer 3 from

7 is a variable resistor 2 connected between the variable resistor 2 and the power supply positive terminal 4.
The voltage level applied to the variable resistor 2 is determined by a voltage dividing resistor connected in series with the variable resistor 2, and a signal of this voltage level is inputted to the microcomputer 3 from the analog port 3b. 8 is the output port 3C of the microcomputer 3.
A display element such as a light emitting diode is connected to one end through a current limiting resistor 20, and the other end is connected to the power supply negative terminal 5. In addition, the output port 3d of the microcomputer 3
A relay drive circuit 9 is connected to the relay drive circuit 9, and when the relay 10 is energized by the drive circuit 9, the contact 10a closes and pressure is increased! Electric power is supplied to the compressor 11 from the AC power source 12, and the compressor 9 is driven. Further, when the relay 10 is de-energized, the contact 10a is open and the compressor 11 is stopped.

FIG. 6 shows the overall configuration of a refrigerator-freezer equipped with a control device having the above circuit configuration. A temperature detection element 1 such as the above-mentioned thermistor is provided in the freezer compartment 14 of the refrigerator-freezer body 13, and a display operation panel has a variable resistor 2 for setting the internal temperature and a display element 8 for indicating an abnormality on the door surface. 15 are provided. Reference numeral 16 denotes temperature detection means for detecting the internal temperature and the set temperature, to which signals from the temperature detection element 1 and the variable resistor 2 are manually input. Reference numeral 17 denotes an internal temperature adjusting means for adjusting the internal temperature based on the detected internal temperature and the set temperature, which determines whether to operate or stop the compressor 11 and also determines whether the temperature detection element 1 is normal or abnormal. 18 is a compressor control means that controls the drive of the compressor 11 based on the determination, and 19 is an abnormality display control means that controls lighting and extinguishment of the display element 8. A detection means is configured.

Next, the operation of the conventional refrigerator-freezer control device will be explained with reference to the flowcharts in FIGS. FIG. 7 is a schematic flow chart showing the entire control program stored in the microcomputer 3. First, in step 100, the power is turned on and initialized, and then the main routine is entered. That is, step 200
The microcomputer 3 has an analog input port 3a,
The voltage signal input from 3b is read, and each analog value is converted into a digital value and stored. Figure 10 shows the correlation between the digital value and the temperature ("C"). In this example, the voltage signals manually input from the analog manual boats 3a and 3b are expressed as "00" to r256J using the 16-way method.
For example, the value at -40°C is rEOJ, +4
The value of 0°C is set to be "10". In other words,
The microcomputer 3 inputs the detected value of the temperature detection element 1 in the range of -40°C to +40°C, and detects the temperature inside the refrigerator. The set value (resistance value) of variable resistor 2 is also input in the same range to the company, and the set temperature is detected. At that time, the temperature detection element 1 is connected to the DC power supply (+Vcc) via the voltage dividing resistor 6.
Therefore, if the internal temperature changes and the detected value (resistance value) of the temperature detection element 1 changes, the voltage signal applied to the analog input port 3a of the microcomputer 3 will also change, as described above. The digital value read into the microcomputer 3 fluctuates. In this way, the microcomputer 3 can read the temperature inside the refrigerator. In addition, since the variable resistor 2 is also connected to the DC type FA (+VcC) via the voltage dividing resistor 7, fluctuations in the voltage signal applied to the analog human power port 3b of the microcomputer 3 can cause The set temperature can be detected.

Next, the process advances to step 300 for eight lines, and a manual temperature determination is performed. Here, as shown in the detailed flowchart in Figure 8,
The magnitude of the digital value of the internal temperature read into the microcomputer 3 and the digital value of the set temperature are compared, and it is determined whether the internal temperature is higher than the set temperature (step 3oB. At this time, the internal temperature If the internal temperature is higher, the compressor operation flag is set (step 302), and if the internal temperature is lower, the flag is reset (step 303). After this manual temperature determination is completed, output is set in step 400. That is, if the compressor operation flag is set, excitation No. 15 is output to the relay drive circuit 9 to excite the relay 10, thereby closing the contact 10a and driving the compressor 11. Conversely, if the compressor operation flag has been reset, a de-energized signal is output to the relay drive circuit 9 to de-energize the relay 10, and at this time the contacts are open and the compressor 11 is stopped.

The above-described operation controls the temperature inside the refrigerator to be kept constant. Here, the detected value (resistance value) of temperature detection element 1
fluctuates depending on the temperature, but its value is less than 140℃ (digital value rEOJ or more) + 40℃ or more (digital value "
10" or less), you will not be able to attend school. Therefore,
At step 500 in FIG. 7, it is determined whether the temperature detection element 1 is abnormal.

FIG. 9 is a detailed flowchart, in which it is determined whether the internal temperature data (digital value) is greater than "EO" (step 501), and if so, an abnormality is output (step 502). Also, the data on the internal temperature is “E”.
If it is smaller than "O", then it is determined whether it is smaller than "10" (step 503), and if it is smaller, an abnormality output is performed in the same way, and at the same time a signal is sent to the display element 8, and an abnormality display is displayed on the display operation panel 15. .

(Problems to be Solved by the Invention) However, in the conventional refrigerator-freezer control device as described above, damage to the temperature detection element (oven, short circuit) or damage to the lead wire, etc. may occur during the inspection process of the production line, for example. Even if an abnormality is determined by detecting a connection failure in the connection part, the inspector may overlook the abnormality indication, and in this case, there is a problem that the refrigerator-freezer is shipped as defective.
Another problem was that abnormal operation of the damper could not be detected. This invention was made to solve these problems, and provides a control device for a refrigerator-freezer that can detect abnormalities in damper operation without overlooking abnormal conditions during the inspection process of a production line, etc. is intended to provide.

[Means for solving problems]

A control device for a refrigerator-freezer according to the present invention includes a temperature detection element that detects an internal temperature of the refrigerator and a variable resistor that sets the internal temperature of the refrigerator, and that detects the temperature of the refrigerator based on the detected value of the temperature detection element and the set value of the variable resistor. In a refrigerator-freezer control device that controls the internal temperature, when the power is turned on, if the detected value of the temperature detection element exceeds a predetermined range, or the set value of the variable resistor exceeds a predetermined range, the cold air passage is shut off. An abnormality detection means is provided to detect and notify these abnormalities when the damper that opens and closes does not operate.

[Effect]

The abnormality detection means checks the detection value of the temperature detection element and the setting value of the variable resistor that sets the internal temperature from the time the power is turned on. If the resistor becomes poorly connected,
The detected value exceeds the predetermined range. At this time, the abnormality detection means detects this and notifies the abnormality. It also checks to see if the damper that opens and closes the cold air passages is working properly, and if an abnormality is detected, it will notify you of the abnormality.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit configuration diagram showing the main parts of a control device, and the same reference numerals as in the conventional FIG. 5 indicate the same parts. In the figure, 21 is a temperature detection element installed in the refrigerator compartment, and 22 is a temperature detection element 2 between the temperature detection element 21 and the positive terminal of the power supply.
1 and a voltage dividing resistor connected in series with the temperature detection element 21.
The voltage level to be applied to is determined, and a signal of this voltage level is manually input to the microcomputer 3 from the analog manual boat 3e. 23 is a variable resistor for setting the temperature of the refrigerator compartment.

24 is a voltage dividing resistor connected in series with the variable resistor 23 between the variable resistor 23 and the power supply positive terminal (+Vcc), which determines the voltage level applied to the variable resistor 23 and outputs a signal of this voltage level. is manually input to the microcomputer 3 from the analog human-powered boat 3f. 24 has one side connected to the output port 3g of the microcomputer 3 and a current limiting resistor 25.
is a display element such as a light emitting diode connected through a ``1''? r, connected to the negative terminal (GND) of the source. In addition, the output port 3h of the microcomputer 3,
Relay drive circuits 26 and 27 are connected to the third quantity,
Relays 28.29 are energized by this drive circuit 26.27. When the relay 28 is energized, the contact 28
a is closed, power from the AC power source 12 is supplied to the fan motor 30, and the fan 30 is driven. relay 28
When is not energized, the contact 28a is open and the fan motor is stopped tL. Further, when the relay 29 is energized, the contact 29a closes and power is supplied from the AC power supply 12 to the motor 31a of the electric damper 31, and the motor 31a of the electric damper 31 is driven.

When the relay 29 is de-energized, the contact 29a is open and the motor 31a of the electric damper 31 is stopped. This electric damper 31 has a reed switch 3 that detects the open/close state.
1b is attached, and the reed switch 31 is activated when the damper is opened.
b is ONL, resistor 9II32 connected in series with this
As a result, an H (high) level voltage signal is generated, and this signal is sent to the human-powered boat 3j of the microcomputer 3.

FIG. 2 shows the overall configuration of a refrigerator-freezer equipped with a control device having the above circuit configuration. Compared to the conventional configuration shown in FIG. 6, as described above, a temperature detection element 21 such as a thermistor is further provided in the refrigerator compartment 33, and a variable temperature sensor for setting the temperature of the refrigerator compartment 33 is provided on the operation panel 15 on the door surface. A resistor 23 and a display element 24 for indicating an abnormality are added. Reference numeral 34 denotes an electric damper control means for controlling the drive of the electric damper 31 based on the determination by the refrigerator internal temperature adjusting means 17, 35 a reed switch detection means for detecting the state of the reed switch 31b of the electric damper 31, and 36 a reed switch detecting means for detecting the state of the reed switch 31b of the electric damper 31; Adjustment means 17
This is a fan motor control means that performs drive control of the fan motor 30 based on the determination.

Next, the operation of the refrigerator/freezer control device having the above configuration will be explained with reference to the flowcharts shown in FIGS. 3, 4, and 8.

FIG. 3 is a schematic flowchart showing the entire control program stored in the microcomputer 3.

First, after initial setting in step 100, in step 600, the microcomputer 3 reads the voltage signals input from the analog human-powered boats 3a, 3b, 3e, 3fh), converts each analog value into a digital value, and stores it. do. The method of converting the digital value is the same as in the prior art, so the explanation will be omitted. Next, the process moves to step 700, where the state of the reed switch 31b of the electric damper 31 is read, and if the human-powered boat 3j is at H level, the electric damper 3
1 is open state (reed switch 31b is ON), L (low)
If the level is the same, it is determined that the reed switch 31b is in the closed state (reed switch 31b is 0FF). Next, the process moves to step 800 and abnormality determination is performed. Here, as shown in the detailed flowchart of FIG. 4, the microcomputer 3 sets the compressor operation flag and the fan motor operation flag (step 801).
An excitation signal is output to the relay drive circuit 9.26 to instantiate the relay 10.28, thereby causing the contacts, 10a, 28
a is closed and the compressor 11 and fan motor 30 are driven.

Next, whether the digital value read from analog input ports 3a, 3b, 3e, and 3f is greater than "EO" or "1"
0” (steps 802 and 803).
). At this time, the digital value is greater than or equal to rEOJ or there is a connection failure, or the variable resistor 2.23 is in an abnormal state due to a connection failure. Therefore, steps 802 and 803
If ↑ is incremented to YES, the process moves to step 804 and an abnormality output is performed. Specifically, when the microcomputer 3 detects an abnormality in the temperature detection element 1 of the freezer compartment 14 and the temperature setting variable resistor 23 of the freezer compartment 33, an abnormality is output from the output port 3C, and at the same time, the display element 8 displays (
No. 3 is sent and an abnormality display is made on the display operation panel 15. Next, the process moves to step 805, and the compressor operation flag and fan motor operation flag are reset. As a result, a de-energized signal is output to relay drive circuit 9.26, relay 10.28 is de-energized, contacts 10a and 28a are opened, and compressor 11 and fan motor 30 are stopped. - In steps 802 and 803 of F, the analog input port 3
If the analog data read from a, 3b, 3e, and 3f is determined to be less than "EO" and more than rlOJ, that is, normal, set the electric damper operation flag in step 806.
), the microcomputer 3 outputs an excitation signal to the relay drive circuit 27 to excite the relay 29, which closes the contact 29a and drives the motor 31a of the electric damper 3. When this motor 31a is driven, the electric damper 3
1 transitions from open to closed or from closed to open. At this time, the input of the human-powered boat 3j is reversed from the H level to the L level because the reed switch 31b is turned from ON to OFF when the electric damper 31 is closed from the fully open state. Also, when opening from the fully open state, the reed switch 31b goes from OFF to ON, so it changes from L level to H level.
Flip to level. Then, in step 8.7.808, it is checked whether the reed switch input has been reversed, and if it is not reversed, it is abnormal, so the process moves to step 804, where an abnormal output is performed from the output boat 3C, and at the same time A signal is sent to the display element 8 and an abnormality is displayed on the display panel 15. Next, the reed switch 31b
If the human power is reversed twice, it is determined to be normal, and the electric damper operation flag is reset (step 809).

As a result, a de-energized signal is output to the relay drive circuit 27, the relay 29 becomes de-energized, the contact 29a opens, and the electric damper 3! Suddenly, the 31a stops. Furthermore, if it is determined that there is an abnormality in the abnormality determination at step 800, the abnormality display continues, the compressor 11 and the fan motor 30 are forcibly stopped, and the process does not proceed to the next step. When the abnormality determination operation is completed, the main routine starts as in the conventional case. That is, the microcomputer 3 converts the voltage signals input from the analog manual boats 3a, 3b, 3e, and 3f into digital values and stores them (step 200).
.

Next, the process moves to step 300 and a temperature input determination is performed. Then, the digital value of the freezer compartment temperature and the digital value of the set temperature are compared to determine whether the freezer compartment temperature is higher than the set temperature (step 301). At this time, if the freezer compartment temperature is higher than the set temperature, set the compressor operation flag and fan motor operation flag (step 302).
If the humidity in the freezer compartment is lower than the set temperature, the flag is reset (step 303). Further, the refrigerator compartment 33 is controlled in the same manner, and if the refrigerator compartment temperature is higher than the set temperature, an electric damper operation flag is set, and if the refrigerator compartment temperature is lower than the set temperature, the flag is reset. When the above-mentioned temperature manual determination operation is completed, an output is set in step 400.

As described above, driving the compressor 11 and fan motor 30,
The freezing room temperature is controlled to be kept constant by stopping the operation, and the refrigerator room temperature is kept constant by opening and closing the electric damper 31.

In the above embodiment, an abnormality in the temperature detection element 1 and variable resistor 2 of the freezing compartment 14 and the temperature detection element 21 and variable resistor 23 of the refrigerator compartment 33 was detected and the abnormality was displayed only on the display element 8. However, in order to identify abnormalities related to each storage compartment, such as the freezer compartment 14 and the refrigerator compartment 33, the microcomputer 3 is provided with a separate output port 3g as shown in FIG. The display element 37 may display an abnormality related to the refrigerator compartment 33.

〔Effect of the invention〕

As explained above, according to the present invention, since the abnormality detection means is provided to detect and notify abnormalities in the detected value, set value, and damper operation of the internal temperature when the power is turned on, the temperature This has the advantage of not overlooking abnormalities in the detection element, variable resistor, or abnormal states of their connections, and also allows detection of abnormalities in damper operation.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram showing an embodiment of the present invention, FIG. 2 is an overall configuration diagram of a refrigerator-freezer equipped with a control device of the circuit configuration, and FIG. 3 shows the control operation of the microcomputer shown in FIG. 1. FIG. 4 is a detailed flowchart showing the abnormality determination operation of the microcomputer, and FIG.
The figure is a circuit configuration diagram showing a conventional example, and FIG. 6 is an overall configuration diagram of a refrigerator-freezer equipped with a control device of the circuit configuration. 7 is a schematic flowchart showing the control operation of the microcomputer in FIG. 5, FIG. 8 is a flowchart showing the input judgment operation in FIGS. 3 and 7, and FIG. 9 is a flowchart showing the abnormality judgment operation in FIG. 7. The detailed flowchart, FIG. 1O, is a correlation diagram showing the correlation between temperature and digital values. l, 21...Temperature detection element 2.23--Variable resistor 3----Microcomputer 8.37...Display element 11...-Compressor 13. ... Freezer/refrigerator body 14 ... Freezer compartment 15 ... Display/operation panel 30 --- Fan motor 31 --- Electric damper 33 --- ...Refrigerating room Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (3)

[Claims] (1) A refrigerator-freezer that is equipped with a temperature detection element that detects the internal temperature and a variable resistor that sets the internal temperature, and that controls the internal temperature based on the detected value of the temperature detection element and the set value by the variable resistor. In the control device, when the power is turned on, if the detected value of the temperature detection element exceeds the predetermined range, the set value of the variable resistor exceeds the predetermined range, or the damper that opens and closes the cold air passage does not operate. A control device for a refrigerator-freezer, characterized in that it is provided with abnormality detection means for detecting and notifying these abnormalities. (2) The control device for a refrigerator-freezer according to claim 1, wherein the abnormality detection means displays the abnormality for each storage compartment, such as the freezer compartment and the refrigerator compartment. (3) The control device for a refrigerator-freezer according to claim 1 or 2, wherein the abnormality detection means stops the compressor and the fan motor for supplying cold air when an abnormality is detected.