JPH0771854A - Energization control device for electric refrigerator - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Regarding an energization control device that supplies electric power to each electric device in an electric refrigerator, abnormalities in each electric device and sudden increases in power consumption are detected in advance, and the electric power is forcibly energized. Abnormal heat generation and sudden increase in power consumption are avoided by shutting off the state. [Structure] Current detection devices 21a to 22g for detecting a current value flowing in each electric device, a current interruption device installed between each electric device and a power supply device for each electric device, and when the current detection device detects an abnormal current And a control device for forcibly interrupting the energization of the corresponding electric device by controlling the current interruption device of the corresponding electric device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current control device for an electric refrigerator for supplying electric power to each electric device installed in the electric refrigerator.

[0002]

2. Description of the Related Art An electric refrigerator controls energization of electric devices such as a cooling device and a defrosting device in accordance with the temperature reached in the refrigerator. Therefore, when the inside of the refrigerator is insufficiently cooled, a plurality of electric devices of the cooling device are simultaneously energized to perform cooling operation until the inside of the refrigerator reaches a predetermined cooling temperature.

In many cases, an electric refrigerator is provided with a warming heater for compensating the internal temperature of each storage room, and a heater for preventing dew condensation is also provided on a partition part of the storage room. A plurality of these electric devices are simultaneously energized to control overcooling and prevent defrosting. In addition, in this case, in order to compensate the heat generation energy of the heater, each electric device of the cooling device is operated to increase the electric energy of the cooling device corresponding to the heat load to maintain the cooling temperature in the refrigerator.

[0004]

By the way, in an electric refrigerator, electric appliances are often energized continuously, and in some cases, they are energized continuously for 24 hours, and are often operated unmanned. Therefore, if the electrical equipment fails due to a component failure or external failure, the rated current will be 5 to 10
If a doubled abnormal current flows and this state continues for a certain period of time or more, heat generation energy may cause dielectric breakdown or thermal deformation of peripheral parts, which may lead to ignition at worst. Particularly in recent electric refrigerators, since many resin materials are used for the housing and the like, there is a disadvantage that the combustion speed is high when the internal electric equipment is ignited and the damage is increased due to burning.

In addition, the electric refrigerator requires the approval of the Ministry of International Trade and Industry according to the Electrical Appliance and Material Control Law which is a safety standard. In this case, the standard of the electric refrigerator is classified according to the power consumption, further according to the rated power consumption of the electric device and the rated power consumption of the electric heating device, and further according to the numerical value, for example, 100 W.
Is classified into more than 200 W and less than 200 W, more than 200 W and less than 300 W, and so on. Therefore, if the power consumption transiently increases rapidly for a short time and exceeds the classification range, new approval from the Ministry of International Trade and Industry is required.

An object of the present invention is to prevent abnormal heat generation of each electric device or sudden increase of power consumption by detecting abnormalities of each electric device or sudden increase of power consumption in advance and forcibly cutting off the energized state. The purpose is to do.

[0007]

The invention according to claim 1 of the energization control device for an electric refrigerator according to the present invention is a current detection device for detecting a value of a current flowing through each electric device in the electric refrigerator, and each electric device. And the current breaker installed between the power supply unit and each electric device and the current breaker of the corresponding electric device is controlled by the current detection device to detect the abnormal current, forcing the energization of the corresponding electric device. And a control device for shutting off.

Further, the invention according to claim 2 of the energization control device for an electric refrigerator according to the present invention is a plurality of energization devices installed for each electric device between each electric device and a power supply device in the electric refrigerator, and each electric device. A control device is provided for monitoring the power consumption of the equipment and forcibly shutting off the power supply device corresponding to the excess electric equipment when the power consumption exceeds a predetermined power consumption range.

[0009]

In the configuration of claim 1 of the present invention, the control device sequentially monitors the value of the current flowing through each electric device in the refrigerator by the current detection device, and detects that an abnormal current is continuously applied to a certain device. Then, the current interrupting device corresponding to the device is controlled to interrupt the current flowing from the power supply device to the device, thereby preventing problems caused by the continuous flow of the abnormal current.

According to a second aspect of the present invention,
The control device sequentially monitors the power consumption of each electric device in the refrigerator, and when it detects a sudden increase in the power consumption of a certain electric device, it controls the energization device corresponding to that electric device to forcibly cut off the energization. , Prevent the power consumption from exceeding the specified range.

[0011]

1 is a front view of an electric refrigerator to which the present invention is applied. The refrigerator body 1 includes a freezer compartment 2 and a refrigerator compartment 3.
Are separated by a partition wall 4, a freezer compartment door 5 is attached to the freezer compartment 2, a refrigerating compartment door 6 is attached to the refrigerating compartment 3, and the refrigerating compartment door 6 has a door switch 7 for detecting opening / closing. Is attached.

2 and 3 are a side sectional view and a partially enlarged sectional view of the electric refrigerator described above. Inside the freezer compartment 2, a cooling circulation fan motor 8 having a winding portion 8a on the rear wall is installed, a cooler 9 is installed on the lower part thereof, and a defrosting heater 10 is installed on the lower part thereof. A temperature sensor 11 having a thermistor structure for measuring the temperature inside the freezer compartment 2 is installed on the upper wall of the freezer compartment 2.

Further, inside the refrigerating compartment 3, an inside lamp 12 for illuminating the inside of the refrigerator is installed on a rear wall, and is connected in series to a power source through a door switch 7. Further, an electric compressor 13 for compressing the refrigerant and a heat radiating condensing fan motor 14 for the condenser are installed at the back of the refrigerator compartment 3.

FIG. 4 shows a first embodiment of the energization control device according to the present invention.
It is a block diagram showing an example of. In this embodiment, each of the above-mentioned electric devices, that is, the defrosting heater 10, the cooling circulation fan motor 8 (rated current of about 0.2 A), the electric compressor 13 is used.
(About 2 A in the same) and the condenser fan motor 14 for heat dissipation (about 0.2 A in the same) respectively, the current detecting devices 21a, 21b, 2
1c, 21d, and energization control relays 22a, 22b, 22c, 22d as current interrupting devices are connected to the AC power supply 23, respectively. Here, the defrosting heater 10 is an electric heating device, and the fan motor 8, the electric compressor 13, and the fan motor 14 are electric devices.

The detection outputs of the current detectors 21a to 21d are input to the controller 24. The contacts of the energization control relays 22a to 22d are controlled to open and close according to a command from the control device 24. The controller 24 has an ALU (Ar
ithmetic logic unit), a program memory, a data memory, etc. are integrated into one chip microcomputer, and are driven by a clock signal from the reference clock oscillator 25. In addition, the analog signal indicating the temperature inside the refrigerator measured by the temperature sensor 11 is an A / D converter 2
It is converted into a digital signal at 6 and input to the control device 24.

Next, the operation of this embodiment will be described with reference to the flow chart shown in FIG. First, when the power is turned on, the control device 24 reads initial values such as the rated current of each electric device (step S1), and then selects the electric device to be monitored (step S2). In this example, since the defrosting heater 10, the cooling circulation fan motor 8, the electric compressor 13, and the heat dissipation condensing fan motor 14 are monitored in this order, the defrosting heater 10 is selected immediately after the power is turned on.

Next, the controller 24 controls the current detector 21.
Of the values a to 21d, the current value is read from the detection device corresponding to the device currently monitored (step S3), and compared with the previously read initial value to determine whether or not an abnormal current is flowing (step S4). .

When it is determined that no abnormal current is flowing, the temperature inside the refrigerator measured by the temperature sensor 11 is read (step S5), and it is determined whether the temperature is within a preset temperature range (step S6). Within the specified temperature range,
Since it is appropriately cooled, the energization control relays 22a to 22
The contact of d is opened, and the energization of the defrosting heater 10, the cooling circulation fan motor 8, the electric compressor 13, and the heat dissipation condensing fan motor 14 is stopped (step S7).

If the temperature is below the predetermined temperature range, it means that it is overcooled, so that the contacts of the energization control relay 22a are closed, the contacts of the energization control relays 22b to 22d are opened, and the defrosting heater 10 is opened.
Only the power is supplied to stop the cooling operation (step S8). If the temperature is equal to or higher than the predetermined temperature range, the cooling is insufficient, so the contact of the energization control relay 22a is opened, and the energization control relay 22b is opened.
The contacts 22d to 22d are closed to start the cooling operation (step S9).

When the processing in steps S7 to S9 is completed, the processing returns to step S2, the next electric device to be monitored is selected, and the above-described processing is repeated. In this way, each electric device is sequentially and repeatedly monitored, and the cooling operation is intermittently controlled to maintain the temperature in the refrigerator within a predetermined temperature range. When the contact of the relay is opened in the processing of step S8 or S9, the processing of steps S3 and S4 may be skipped in the next processing, but in this example, when the current value of zero is detected in step S3. In step S4, it is determined that the current is normal, and the process proceeds to step S6.

When the control device 24 detects an abnormal current of the electric device being monitored in the repetition of this series of processing (step S4), the control device 24 opens the contact of the energization control relay corresponding to the device and forcibly. Then, the circuit is cut off (step S10), and after a lapse of a certain time (step S11), the process returns to step S2.

For example, if the winding portion 8a of the fan motor 8 is short-circuited for some reason and a large current rushes, a current of about 2 A flows, but the household breaker does not operate at this level of current. When the state continues, the temperature rises due to heat generation, the peripheral members are softened, and the ignition due to the short-circuit spark may ignite the peripheral materials. However, in the present embodiment, the current detection device 21b detects an abnormal current flowing through the fan motor 8 and detects the occurrence of an abnormality in the energization control relay 2
Since the circuit is forcibly cut off by 2b, it is possible to avoid abnormal heat generation before it occurs.

This series of operations will be described with reference to the drive state diagram shown in FIG. First, since the cooling operation is initially performed, the freezing room temperature (Fig. A) is lowered, and the energization control relay 22b of the electric device (for example, the fan motor 8) of the cooling device is cooled.
(Fig. B) is closed, and a rated current of about 0.1 A is flowing through the current detection device 21b (Fig. C). In addition, the temperature of the peripheral members (Fig. D) is also decreasing.

At time t1, the control device 24 determines that the cooling is overcooling, and the contacts of the energization control relays 22b to 22d are opened to stop the cooling operation. As a result, the temperature of the freezer compartment and the temperature of the peripheral members gradually rise. At time t2, the control device 24 detects that the temperature of the freezing compartment has become equal to or higher than a predetermined temperature range, and the energization control relays 22b to 2b.
The contact of 2d is closed and the cooling operation is restarted. As a result, the temperature of the freezer compartment and the temperatures of the peripheral members fall again. In this way, the cooling operation and the stop thereof are repeated to maintain the temperature of the freezing room within a predetermined temperature range (-15 to -25 ° C).

In this state, when the current detection device 21b detects that an abnormal current of about 2A has flown into the fan motor 8 at time t10 (FIG. C), the control device 24 turns on the contact of the energization control relay 22b at time t11. The circuit of the fan motor 8 and the AC power supply 23 is forcibly cut off by opening. This prevents an abnormal current from continuously flowing to the fan motor 8 and prevents dielectric breakdown and thermal deformation of peripheral parts.

Next, a second embodiment of the present invention will be described. FIG. 7 is a schematic side sectional view of an electric refrigerator to which the present invention is applied, and the same parts as those in FIG.

In the present embodiment, an electric motor 15 for driving an electric damper is installed above the interior light 12 in the refrigerating compartment 3 and the interior light 1
An in-compartment heat retention heater 16 is installed below 2. Further, a partition plate dew prevention heater 17 is attached to the front surface of the partition wall 4. The other structure is the same as the structure shown in FIG.

FIG. 8 shows a second embodiment of the energization control device according to the present invention.
It is a block diagram showing an example of. The electrical equipment that controls energization is a cooling circulation fan motor 8 (rated current of about 0.2
A), electric compressor 13 (about 2 A), heat-dissipating condensing fan motor 14 (about 0.2 A) and electric damper driving motor 15 (about 1.5 A), and defrost heater 10. (Approx. 1.5A), in-house heat insulation heater 16 (approx. 0.1A)
A) and partition plate dew prevention heater 17 (approx. 0.2A)
And other electric heating equipment.

Since these electric devices are control devices (control devices) that do not interfere with the main cooling function of the refrigerator even if they are not energized at all times, an increase in power consumption is prevented by controlling the energization of each of these devices. . On the other hand, the active device (energy conversion device) performs the main cooling function of the refrigerator, and thus is not a target of energization control.

In FIG. 8, each of the above-described electric devices is connected to the power supply device 23 via the energizing relays 22a to 22g functioning as energizing devices. That is, the defrosting heater 10 passes through the energizing relay 22a, the fan motor 8 passes through the energizing relay 22b, the electric compressor 13 passes through the energizing relay 22c, the fan motor 14 passes through the energizing relay 22d, and the electric damper. The driving electric motor 15 is connected to the power supply device 23 via the energization relay 22e, the inside heat retention heater 16 is connected to the energization relay 22f, and the partition plate dew prevention heater 17 is connected to the power supply device 23 via the energization relay 22g.

Each contact of the energizing relays 22a to 22g is controlled to open / close according to a command from the controller 24. The control device 24 is a one-chip microcomputer in which an ALU (Arithmetic Logic Unit), a program memory, a data memory and the like are integrated, and is driven by a clock signal from the reference clock oscillator 25. Further, in the control device 24, an analog signal indicating the temperature inside the refrigerator measured by the temperature sensor 11 is converted into a digital signal by the A / D converter 26 and input.

Next, the operation of this embodiment will be described with reference to the flow chart shown in FIG. First, when the power is turned on, the control device 24 reads the power consumption value set in advance for each electric device (step S21).
Here, the power consumption value of each electric device is about 12 W for the fan motors 8 and 14, about 8 W for the electric damper driving motor 15, and about 1 W for the electric compressor 13 and the defrosting heater 10.
50 W, the inside heat retention heater 16 is about 10 W, and the partition plate dew prevention heater 17 is about 20 W.

Next, the electrical equipment to be monitored is selected (step S22). In this example, since the cooling fan motor 8 is monitored in order, the cooling fan motor 8 is selected immediately after the power is turned on.

Next, the control unit 24 obtains the total power consumption of the electric devices which are currently energized (step S23),
It is determined whether power consumption is increasing (step S2).
4). When it is determined that the power consumption has not increased, the internal temperature measured by the temperature sensor 11 is read (step S25), and it is determined whether the temperature is within a preset temperature range (step S26). If the temperature is within the predetermined temperature range, all the energizing relays 22a to 22a are appropriately cooled.
The contact point g is opened, and energization to all electric devices is stopped (step S27).

If the temperature is lower than the predetermined temperature range, the contact of the energizing relay of the defrosting device is closed and the contact of the energizing relay of the cooling device is opened because it is overcooled. That is, the energizing relay 22
Heater 1 for defrosting by closing the contacts a, 22f, 22g
0, in-compartment heat retention heater 16, partition plate dew prevention heater 17
Only the power is supplied, and the power supply to the cooling device is stopped (step S
28).

If the temperature is above the predetermined temperature range, cooling is insufficient, so the contact of the energizing relay of the cooling device is closed and the contact of the energizing relay of the defrosting device is opened. That is, the energizing relay 2
2b to 22d and 22e are closed to energize only the cooling fan motor 8, the electric compressor 13, the condensing fan motor 14, and the electric motor 15 for driving the electric damper, and deenergize the defroster (step S29). .

When the processing in steps S27 to S29 is completed, the procedure returns to the processing in step S22, the next electric device to be monitored is selected, and the above-described processing is repeated. In this manner, each electric device is sequentially and repeatedly monitored, and the cooling operation is intermittently controlled to maintain the temperature in the refrigerator within a predetermined temperature range. When the relay contact is opened in the process of step S28 or S29, the process of step S24 may be skipped in the next process.

In the repetition of this series of processing, when the control device 24 detects an increase in the power consumption of the electric device being monitored (step S24), the control device 24 opens the contact of the energizing relay corresponding to the device and forcibly. The power supply is cut off (step S30), and after a lapse of a certain time (step S31), the process returns to step S22.

For example, when the fan motor 8 is energized, the rated current is about 0.2 A, but a current higher than that may flow for some reason and power consumption may increase. The control device 24 detects this and forcibly shuts off the energization relay 22a, and avoids it before the power consumption increases.

Next, the series of operations described above will be described with reference to the drive state diagram shown in FIG. In the figure,
(a) shows the temperature change in the freezer, and (b) shows the electric compressor 1.
3 shows the open / closed state of the energizing relay 22c of FIG. 3, FIG. 6 (c) shows the open / close state of the energizing relay 22b of the cooling fan motor 8, and FIG.
The open / closed state of d is shown, and the figure (e) shows the change of total power consumption.

First, since the cooling operation is initially performed,
The freezing room temperature (Fig. A) is lowered, the energizing relay 22c (Fig. B) of the cooling compression motor 13 is closed, and a rated current of about 2 A is flowing. The total power consumption at this time is about 200 W (Fig. E).

At time t1, the control device 24 determines that the cooling is overcooling, and the contact of the energizing relay related to the cooling device is opened to stop the cooling operation. As a result, the temperature of the freezer compartment and the temperature of the peripheral members gradually rise. At time t2, the control device 24 detects that the temperature of the freezing compartment has reached the predetermined temperature range or higher, closes the contacts of the energizing relays related to the cooling device again, and restarts the cooling operation. As a result, the temperature of the freezer drops again. In this way, the cooling operation and the stop thereof are repeated to keep the temperature of the freezing room within a predetermined temperature range (-15
To -25 ° C).

In this state, at time t10, for example, when the controller 24 detects that a current for increasing the power consumption flows in the fan motor 8 and the total power consumption increases (FIG. 10e).
The control device 24 opens the contact of the energization relay 22b of the fan motor 8 at time t11 to forcibly disconnect the circuit between the fan motor 8 and the power supply device 23. As a result, it is possible to prevent the current for increasing the power consumption from continuously flowing to the fan motor 8,
Prevent a sudden increase in power consumption of electric refrigerators.

[0044]

According to the present invention, even if an abnormal current flows through an electric device for some reason or a current that increases the power consumption of the electric device flows, the control device detects it and causes the energizing relay to detect it. Since the circuit is interrupted and the electric power to the electric equipment is forcibly stopped, it is possible to prevent the electric equipment from being destroyed, the peripheral members from being deformed, the worst-case ignition, or to increase the power consumption of each electric equipment. It is possible to provide an electric refrigerator that is prevented in advance and can be used safely, or an electric refrigerator that does not exceed specified power consumption.

[Brief description of drawings]

FIG. 1 is a front view of an electric refrigerator to which the present invention is applied.

FIG. 2 is a side sectional view of the electric refrigerator shown in FIG.

FIG. 3 is a partially enlarged sectional view of FIG.

FIG. 4 is a block diagram showing a first embodiment of the energization control device according to the present invention.

FIG. 5 is a flowchart illustrating the operation of the first embodiment.

FIG. 6 is a drive state diagram illustrating the operation of the first embodiment.

FIG. 7 is a side sectional view of another electric refrigerator to which the present invention is applied.

FIG. 8 is a block diagram showing a second embodiment of the energization control device according to the present invention.

FIG. 9 is a flowchart illustrating the operation of the second embodiment.

FIG. 10 is a drive state diagram illustrating the operation of the second embodiment.

[Explanation of symbols]

 1 Refrigerator Main Body 2 Freezer Room 3 Refrigerator Room 4 Partition Wall 5 Freezer Room Door 6 Refrigerator Room Door 7 Door Switch 8 Cooling Circulation Fan Motor 9 Cooler 10 Defrosting Heater 11 Temperature Sensor 12 Interior Light 13 Electric Compressor 14 For Heat Dissipation Condensing fan motor 15 Electric damper driving electric motor 16 In-compartment warming heater 17 Partition plate dew prevention heater 21a to 21d Current detection device 22a to 22g Energization control relay 23 AC power supply 24 Control device 25 Reference clock oscillator 26 A / D converter

Claims (4)

[Claims] 1. A current detection device for detecting a value of a current flowing through each electric device in an electric refrigerator, a current interruption device installed between the electric device and a power supply device for each electric device, and the current detection device. A control device for controlling a current cutoff device of a corresponding electric device when an abnormal current is detected to forcibly cut off the energization of the corresponding electric device, and a conduction control device for an electric refrigerator. . 2. A plurality of energization devices installed for each electric device between each electric device and a power supply device in an electric refrigerator, and power consumption of each electric device is monitored to exceed a predetermined power consumption range. And a controller for forcibly shutting off the current-carrying device corresponding to the excess electric device, and a power-supply controller for an electric refrigerator. 3. The energization control device for an electric refrigerator according to claim 1, wherein the electric device is a device for cooling. 4. The energization control device for an electric refrigerator according to claim 1, wherein the electric device is a defrosting device.