KR19990048874A - Control device of anti-dew heater in refrigerator and its method - Google Patents

Abstract

The present invention relates to a control apparatus and a control method of an anti-wold heater of the refrigerator to improve the performance of the refrigerator and reduce the power consumption by controlling the amount of heat generated by the anti-wheat heater installed in the door of the refrigerator according to the outside temperature. It is about.

To this end, the present invention stores a predetermined control program including an anti-dew heater, an outside air temperature sensor for detecting an outside air temperature of the refrigerator, and a program for controlling the heater, and receives an output signal of the outside air temperature sensor. A microcomputer, phase control means for controlling a phase of a power supply voltage applied to the heater under control of the microcomputer, and detecting a reference point of the power supply voltage for phase control of the power supply voltage and inputting the same to the microcomputer. And zero crossing detection means.

Therefore, the present invention adjusts the operation phase delay time of the thyristor, which is a kind of a contactless relay, according to the outside temperature sensed by the outside temperature sensor, thereby preventing excessive heat generation in the heater.

Description

Control device of anti-dew heater in refrigerator and its method

The present invention relates to a control apparatus and a method for preventing dew condensation heater of the refrigerator, and more particularly, to improve the performance of the refrigerator by controlling the amount of heat generated by the dew condensation prevention heater installed in the door of the refrigerator according to the ambient temperature The present invention relates to a control apparatus of a dew preventing heater of a refrigerator and a method of controlling the same.

As is well known, when the commercial power is applied to the refrigerator and operated, the internal temperature of the refrigerator is lower than the outside air temperature. If the inside temperature is lower than the outside temperature, the temperature difference may cause dew to form on the boundary between the inside and the outside air, especially at the edge of the refrigerator door. This is because the cold temperature inside the refrigerator and the hot temperature of the outside air cause heat transfer through the edge material of the refrigerator door and form the dew point temperature. In particular, when the air atmosphere of the outside air is hot and humid, a large amount of dew may form on the edge of the refrigerator door.

If dew is formed around the door of the refrigerator as described above, not only the image of the product is bad, but also hygiene is not good, and the dew may flow down to the floor to dirty the floor.

Therefore, dew should be prevented from forming at the edge of the refrigerator, particularly at the edge of the refrigerator door, and an example of the related art for preventing dew from forming at the edge of the refrigerator door is schematically illustrated in FIG. 1.

Referring to FIG. 1, a heater 10 is installed at an edge of the door 1. Power is applied to the heater 10 during operation of the refrigerator. Therefore, since the edge of the door 1 in which the heater 10 is installed may maintain a predetermined temperature or more during operation of the refrigerator, dew is prevented from forming around the edge of the door 1. That is, when the heater 10 installed at the edge of the door 1 is operated, the surface temperature around the edge of the door 1 rises so that dew point temperature is not formed, so that dew condensation is prevented. Reference numeral 2 which is not described in FIG. 1 is a refrigerator cabinet (body) in contact with the door 1.

However, since the heater 10 according to the related art is supplied with power by the control device as shown in FIG. 2, the power consumption of the refrigerator increases and the cooling efficiency of the refrigerator decreases. That is, referring to FIG. 2, when the microcomputer 20 of the refrigerator control device outputs a high signal to the inverter 22 which is a driving driver connected to the coil of the relay 24, the output terminal of the inverter 22 is grounded. 24. The coil is excited. When the relay 24 coil is excited, the relay 24 contact is turned on, and commercial power is applied to the heater 10. When commercial power is applied to the heater 10, since the heater 10 generates heat, dew condensation around the edge of the refrigerator door 1 is prevented as described above. However, when the contact point of the relay 24 is turned on, power consumption may occur more than necessary because commercial power is applied to the heater 10 as it is regardless of the outside temperature. For example, when the capacity of the heater 10 is determined for the refrigerator capacity or the highest temperature and the highest humidity in the summer, the capacity of the heater 10 becomes over spec. In the low temperature and low humidity conditions in winter. In winter, the power consumption increases due to the heating of the heater 10, and there is a problem in that the cooling efficiency of the refrigerator is lowered.

The present invention was created to solve the above problems, by controlling the amount of heat generated by the dew condensation prevention heater installed in the refrigerator door according to the outside temperature dew of the refrigerator to improve the performance of the refrigerator and reduce the power consumption It is an object of the present invention to provide a control apparatus for a condensation preventing heater and a control method thereof.

1 is a configuration diagram schematically showing a dew preventing heater of a refrigerator;

2 is a block diagram showing a control device of the dew preventing heater of the conventional refrigerator,

3 is a block diagram showing a control device of the dew preventing heater of the refrigerator according to the present invention;

Figure 4 (a) (b) is an embodiment showing the SCR and triac respectively of the phase control unit applied to the present invention,

5 is a flow chart of the control method of the present invention;

Figure 6 (a) to Figure 6 (f) is a view showing the power supply voltage, heater heating amount and the like achieved according to the action of the present invention.

<Description of the symbols for the main parts of the drawings>

10: dew preventing heater 20: microcomputer

31: outside temperature sensor 33: power supply voltage zero crossing detection unit

35: phase control unit

In order to achieve the above object, a control apparatus of a dew preventing heater of a refrigerator according to the present invention,

A microcomputer for storing a predetermined control program including an anti-dew heater, an outside air temperature sensor for sensing an outside air temperature of the refrigerator, a program for controlling the heater, and receiving an output signal of the outside air temperature sensor; Phase control means for controlling the phase of the power supply voltage applied to the heater according to the control of the computer, and zero crossing for detecting a reference point of the power supply voltage and inputting it to the microcomputer for phase control of the power supply voltage. This feature is characterized in that it includes a detection means.

In a preferred embodiment of the present invention, the phase control means is a thyrister such as triac (SIAC), silicon controlled rectifier (SCR).

In addition, the control method of the dew preventing heater of the refrigerator of the present invention implemented by the controller of the present invention,

In the control method for preventing dew formed around the refrigerator door,

Sensing an outside air temperature outside the refrigerator through an outside air temperature sensor;

Comparing the outside temperature with predetermined set temperatures, respectively;

Adjusting a phase of a power supply voltage applied to an anti-dew heater according to a comparison result between the outside air temperature and the set temperatures;

And applying the power supply voltage of the adjusted phase to the anti-dew heater through a thyristor.

In a preferred embodiment of the method of the invention, the set temperatures are 10 ° C, 20 ° C, 30 ° C.

In a preferred embodiment of the method, the method further comprises detecting a zero crossing point of the power supply voltage to adjust the phase of the power supply voltage.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the control device and the control method of the dew preventing heater of the refrigerator according to the present invention. For the convenience of description, the same reference numerals are used for constituent members that have the same function as the constituent members used in the prior art.

Figure 3 is a block diagram showing the configuration of an embodiment according to the present invention, Figure 4 (a) (b) shows an embodiment of a phase control which is a component of the present invention, Figure 4 (a) is a phase control SCR Figure 4 (b) shows the case where the phase control unit is TRIAC. 5 is a flowchart illustrating an embodiment of the method of the present invention, and FIG. 6 is a graph showing a power supply voltage, a heater heating amount, and the like, which are achieved according to the operation of the present invention.

As shown in FIG. 3, the control device of the present invention includes an anti- dewing heater 10 installed at an edge of the refrigerator door 1, and an outside air temperature sensor installed at an upper portion of the refrigerator to sense an outside air temperature of the refrigerator. 31 and a microcomputer 20 that stores a predetermined control program including a program for controlling the heater 10 and receives an output signal of the outside temperature sensor 31 and the microcomputer 20 according to the control of the microcomputer 20. Thyristor 35, which is a phase controller for controlling the phase of the power supply voltage (commercial power supply voltage) applied to the heater 10, and a reference point of the power supply voltage for the phase control of the commercial power supply voltage are detected and the microcomputer 20 It includes a zero crossing detection unit 33 input to the (). The thyristor 35, which is the phase control unit, is an SCR 35a (Fig. 4 (a)) or a triac 35b (Fig. 4 (b)), which is a kind of a contactless relay as shown in Fig. 4.

In addition, as shown in Figure 5, the control method of the present invention comprises the steps of detecting the outside temperature (TEMP) of the outside of the refrigerator through the outside temperature sensor 31 (S10); Comparing the outside temperature TEMP sensed in step S10 with predetermined set temperatures, for example, 10 ° C., 20 ° C., and 30 ° C. (S20), S30, and S40; For example, to adjust the phase of the power supply voltage applied to the anti-dew heater 10 according to the comparison result between the outside temperature TEMP and the set temperatures 10 ° C. (20 ° C.) (30 ° C.). If the TEMP is less than 10 ° C, as shown in Fig. 6 (a), the phase of the commercial power supply voltage having a frequency of 60 Hz is controlled 135 DEG per cycle, thereby delaying the delay time at a zero crossing position of the commercial power supply 6 msec. Afterwards, the commercial power is applied to the heater 10, and if the outside temperature TEMP is less than 20 ° C, the commercial power is applied to the heater 10 after 4 msec. When the TEMP is less than 30 ° C., a step S25, S35, and S45 are performed to apply the commercial power to the heater 10 after 2 msec of delay time Ton (phase 45 ° control). Here, as described above, the commercial power source adjusted as described above is applied to the anti- dewing heater 10 through the thyristor 35 controlled by the microcomputer 20.

It will be apparent to those skilled in the art that the flowchart algorithm of the control method of the present invention shown in FIG. 5 can be programmed and stored in the microcomputer 20.

The operation of the present invention configured as described above will be described with reference to FIGS.

First, referring to FIG. 6, FIG. 6A illustrates an output voltage waveform of the thyristor 35 obtained by controlling the thyristor 35 using the zero crossing point detected by the commercial power supply voltage zero crossing detection unit 33. 6B illustrates the effective value input voltage Vrms of the heater 10, which is inversely proportional to the phase delay time Ton of FIG. 6A.

FIG. 6C illustrates the relationship between the effective value input voltage Vrms of the heater 10 and the calorific value of the heater 10, and as shown, the calorific value is increased in proportion to the effective value input voltage Vrms. Therefore, the temperature of the heater 10 is adjustable by the microcomputer 20, which is achieved by adjusting the phase delay time Ton through the detection of the zero crossing point in the zero crossing detector 33.

FIG. 6D illustrates an example of a relationship between the dew point temperature and the outside air temperature TEMP sensed by the outside air temperature sensor 31, and FIG. 6E shows the optimum calorific value at which dew point does not occur. The relationship with the phase delay time Ton is shown. In FIG. 6E, each of the phase delay times Ton, a, b, and c may have a significant difference depending on the insulation state of the refrigerator and the resistance of the heater 10. In the present specification, the phase delay times Ton, a, b are different from each other. and c are taken as 6 second, 4 second, and 2 second as an example. Each of the phase delay times Ton, a, b, and c is an optimal input voltage at which dew point does not occur when the input voltage of the heater 10 is varied while the refrigerator is placed in a thermostat and the temperature of the outside air is varied to adjust the heat generation amount. You can find the value of.

As a result, the microcomputer 20 shown in FIG. 3 and in which the program of the flowchart algorithm of FIG. 5 is stored may be used in the SCR 35a or the triac according to the ambient temperature TEMP sensed by the ambient temperature sensor 31. By controlling the operation phase delay time Ton of the thyristor 35 which is 35b), it is possible to improve the cooling efficiency of the refrigerator and to reduce the power consumption by preventing heat generation more than necessary in the heater 10.

The above description will be described with reference to FIGS. 3 and 5 as follows.

When 60Hz commercial power (110 volts or 220 volts) is applied to the refrigerator, the microcomputer 20 may compare the temperature sensing signal detected by the outside temperature sensor 31 and the commercial power voltage detected by the zero crossing detection unit 33. The zero crossing point is input. Then, the microcomputer 20 controls the thyristors 35a or 35b of the phase control unit 35 according to the outside temperature sensed by the outside temperature sensor 31 to control the phase of the power supply voltage applied to the heater 10. Do That is, the microcomputer 20 controls the SCR 35a or the triac 35b based on the zero crossing point detected by the zero crossing detection unit 33 to adjust the phase of the power source power applied to the heater 10. By controlling, the amount of heat generated by the heater 10 is adjusted.

In addition, when the phase control method of the power supply voltage performed by the microcomputer 20 is described with reference to FIG. 5, as described above, the microcomputer 20 uses the outside air temperature sensor 31 through the outside air temperature TEMP. ) (S10). Then, the microcomputer 20 compares the outside temperature TEMP with the above-mentioned set temperatures 10 ° C, 20 ° C and 30 ° C, respectively (S20) (S30) and S40. If the outside temperature TEMP is less than 10 ° C. in step S20, since the outside temperature is low, the microcomputer 20 controls the power supply voltage phase by 135 ° such that the phase delay time Ton of FIG. 6 is 6 msec. (S25). If the outside temperature TEMP is less than 20 ° C. in step S30, since the outside temperature is in a medium state, the microcomputer 20 may have a phase delay time Ton of the power supply voltage of 4 msec as described with reference to FIG. 6. The power supply voltage phase is controlled by 90 ° (S35). If the outside temperature TEMP is less than 30 ° C. in step S40, since the outside temperature is high, the microcomputer 20 controls the power supply voltage phase by 45 ° such that the phase delay time Ton of the power supply voltage becomes 2 msec (S45). ). In the above, the correspondence relationship between the voltage phase angle and the phase delay time Ton is a case where the frequency of the power supply voltage is 60 Hz, but the present invention is not limited thereto.

Thus, the present invention is to adjust the heater phase (Ton) of the operation phase delay time (Ton) of the thyristor (35) SCR (35a) or triac (35b) according to the ambient temperature (TEMP) sensed by the outside temperature sensor (31). By preventing excessive heat generation in 10), it is possible to improve the cooling efficiency of the refrigerator and to reduce power consumption.

As described above, the controller and method for preventing dew condensation heater of the refrigerator of the present invention can improve the performance of the refrigerator and reduce power consumption by controlling the amount of heat generated by the dew condensation prevention heater installed in the refrigerator door according to the outside temperature. It provides the benefits. That is, the present invention improves the cooling efficiency of the refrigerator by controlling the operation phase delay time of the thyristor, which is a kind of a contactless relay, according to the ambient temperature sensed by the outside air temperature sensor, and thus prevents heat generation from the heater. It has the effect of making savings possible.

On the other hand, as described above, the control device and the method of the anti-dew heater of the refrigerator of the present invention is not limited to the above embodiment and can be carried out by applying a number of manufacturing modifications without departing from the spirit and scope of the present invention.

Claims (7)

Dew-proof heater; An outside temperature sensor for sensing an outside temperature of the refrigerator; A microcomputer storing a predetermined control program including a program for controlling the heater and receiving an output signal of the outside temperature sensor; Phase control means for controlling a phase of a power supply voltage applied to the heater according to the control of the microcomputer; And And a zero crossing detecting means for detecting a reference point of the power supply voltage and inputting the reference point to the microcomputer for controlling the phase of the power supply voltage. The apparatus of claim 1, wherein the phase control means is a thyristor. 3. The apparatus of claim 2, wherein the thyristor is a triac (TRIAC). The apparatus of claim 2, wherein the thyristor is a silicon controlled rectifier (SCR). In the control method for preventing dew formed around the refrigerator door, Sensing an outside air temperature outside the refrigerator through an outside air temperature sensor; Comparing the outside temperature with predetermined set temperatures, respectively; Adjusting a phase of a power supply voltage applied to an anti-dew heater according to a comparison result between the outside air temperature and the set temperatures; And applying the power supply voltage of the adjusted phase to the anti-dew heater through a thyristor. The apparatus of claim 5, wherein the set temperatures are 10 ° C., 20 ° C., and 30 ° C. 7. 6. The apparatus of claim 5, further comprising detecting a zero crossing point of the power supply voltage to adjust the phase of the power supply voltage.