KR100212677B1 - Apparatus for compensating evaporation temperature of heat pump - Google Patents

Abstract

The present invention relates to a device for compensating the evaporation temperature of a heat pump. In the conventional heating cycle, since the pressure difference between the condenser and the evaporating heat exchanger is almost constant, the indoor refrigerant temperature is also reduced when the outdoor refrigerant temperature drops by a predetermined amount. As a result, there is a problem in that the descending and thus cannot supply adequate warm air to the room. In the present invention, first and second evaporation temperature sensors are respectively installed at the inlet of the evaporation heat exchanger and the compressor. An electric heater whose heat generation is controlled by the temperature difference of the second evaporation temperature sensor is installed at the outlet side of the evaporation heat exchanger, and an expansion mechanism for increasing the specific volume of the refrigerant according to the temperature of the outside air is provided. The evaporation temperature of the refrigerant in the cabin and the specific volume of the refrigerant flowing into the compressor are prevented from falling excessively. The hot air of the proper temperature is always supplied to the room from the heat exchanger for condensation, and there is an effect of preventing the cost increase of the consumer by excluding the use of a separate auxiliary heating device.

Description

Evaporating Temperature Compensation Device for Heat Pump

The present invention relates to a device for compensating an evaporation temperature of a heat pump, and in particular, an electric heater is installed at an outlet of an evaporator, and a capillary tube which can raise a specific volume of a refrigerant flowing into a compressor is always installed so that a warm air of a proper temperature is always brought into the room. An apparatus for compensating an evaporation temperature of a heat pump to be supplied.

A general refrigeration cycle is applied to a refrigerator or an air conditioner to absorb heat from the outside or release heat to the outside to keep food fresh and to keep the indoor environment pleasant by cooling / heating the room.

Such a refrigeration cycle includes a compressor for converting a gaseous refrigerant of low temperature and low pressure into a gaseous refrigerant of high temperature and high pressure, and a condenser for changing a gaseous refrigerant of high temperature and high pressure changed into a liquid refrigerant of high temperature and high pressure in the compressor (hereinafter, Mixed with a heat exchanger for condensation), a capillary tube for converting the high temperature and high pressure liquid refrigerant changed in the condenser into a low temperature and low pressure liquid refrigerant, and the external heat while changing the low temperature low pressure liquid refrigerant in the capillary into a gas state. It is composed of an evaporator (hereinafter, mixed with the heat exchanger for evaporation), wherein each of the components are connected to the refrigerant pipe.

The refrigeration cycle of the heat pump that can serve as cooling / heating by applying the refrigeration cycle as shown in FIG.

That is, in the refrigeration cycle for the heat pump, one side of the four-way valve (2) is coupled to the outlet of the compressor (1), the other side of the four-way valve (2) condensation heat exchanger (hereinafter, mixed with a condenser) (3) is connected, followed by the condensation heat exchanger (3), followed by an expansion mechanism, commonly referred to as a capillary tube (4), followed by the capillary tube (4), followed by an evaporation heat exchanger (hereinafter referred to as a mixture with an evaporator). (5) is connected, it is coupled to the other side of the four-way valve (2) following the evaporation heat exchanger (5), the accumulator (not shown) on the other side of the four-way valve (2) The accumulator is connected to the inlet of the compressor 1.

Here, as shown in FIG. 2, the expansion mechanism includes a first capillary tube 4a having a short length and a second capillary tube 4b relatively longer than the first capillary tube 4a is connected in series. A bypass pipe 4c connected to the inlet of the second capillary tube 4b is connected to the inlet of the capillary tube 4a in parallel, and the bypass pipe 4c prevents the backflow of the refrigerant during the heating operation. 4 d of check valves are provided.

In the figure, reference numeral 3a denotes an indoor fan (sirocco fan), and 5a denotes an outdoor fan (axial flow fan).

In the heat pump refrigeration cycle configured as described above, while changing the direction of the four-way valve (2) to change the role of the condensation heat exchanger (3) and evaporation heat exchanger (5) to be used for cooling or heating do.

That is, when the refrigeration cycle for the heat pump is cooling, the indoor heat exchanger acts as an evaporator, while when heating, the indoor heat exchanger acts as a condenser. Of course, the outdoor heat exchanger at this time acts as a condenser when cooling, while acting as an evaporator when heating.

Here, the sequence of the refrigerant flow for the case where the refrigeration cycle for the heat pump is used for heating is as follows.

First, the refrigerant is supplied to the compressor according to the operation of the compressor (1)-four-way valve (2)-condenser (3)-capillary tube (4)-evaporator (5)-four-way valve (2)-accumulator (not shown)-compressor It proceeded through the procedure of (1), and the indoor side sirocco fan 3a discharged the hot air heat-exchanged in the condenser 3 to the room, and it maintained the heating state.

At this time, the operation of the expansion mechanism according to the temperature of the outside air is as follows.

That is, when the temperature of the outside air falls below 0 ° C., the temperature and pressure of the refrigerant passing through the condensation heat exchanger 3 begin to drop rapidly, and are introduced into the bypass pipe 4c having a relatively low resistance. The refrigerant introduced into the bypass tube 4c was expanded while passing through the second capillary tube 4b while pushing the check valve 4d and entering the heat exchanger 5 for evaporation.

However, in general, since the pressure difference between the condenser 3 and the evaporator 5 is almost constant in the heating cycle of the heat pump, when the refrigerant temperature on the outdoor side drops by a predetermined amount, the refrigerant temperature on the indoor side decreases by that much. Eventually there was a problem that can not supply the proper warm air into the room.

For example, when the external temperature falls below 0 ° C., the evaporation temperature of the refrigerant flowing through the evaporation heat exchanger 5 drops below −5 ° C., so that the condensation temperature of the refrigerant flowing into the heat exchanger 3 for condensation 3 decreases. As the temperature is lowered to about 41 ° C, the temperature of the warm air discharged to the room becomes 40 ° C or less, causing consumers to be dissatisfied with heating as well as using a separate auxiliary heating device such as a fan heater. This was to happen.

In addition, in the conventional expansion mechanism 4 as described above, since the refrigerant ejected from the heat exchanger 3 for condensation passes through at least a long second capillary tube 4b, the pressure of the refrigerant drops rapidly and thus the evaporation heat exchanger ( There was also a problem that the heating efficiency of the heat pump is lowered because the specific volume of the refrigerant flowing into the compressor 1 through 5) is too low.

Accordingly, the present invention has been made in order to solve all the problems of the conventional heating cycle, the main purpose of the present invention is to prevent the evaporation temperature of the refrigerant in the evaporation heat exchanger to drop excessively condensation temperature of the refrigerant in the condensation heat exchanger By maintaining the proper temperature at all times, the customer is always satisfied with the warm air discharged from the heat exchanger for condensation, and the evaporation of the heat pump which can prevent the increase of the cost by eliminating the use of a separate auxiliary heating device. The purpose is to provide a temperature compensation device.

In addition, another object of the present invention is to increase the specific volume of the refrigerant flowing into the compressor through the heat exchanger for condensation and evaporation heat exchanger, thereby increasing the compression efficiency of the compressor and thereby increasing the circulation temperature of the refrigerant To provide.

1 is a schematic view showing the configuration of a refrigeration cycle in a conventional heat pump.

Figure 2 is a schematic view showing an expansion mechanism in the refrigeration cycle of the conventional heat pump.

Figure 3 is a schematic diagram showing the configuration of the refrigeration cycle in the heat pump of the present invention.

Figure 4 is a schematic view showing an expansion mechanism in the refrigeration cycle of the heat pump of the present invention.

Figure 5 is a longitudinal cross-sectional view showing the configuration of the electric heater in the refrigeration cycle of the heat pump of the present invention.

Figure 6 is a P-H diagram showing the effect of the heat pump of the present invention compared to a conventional heat pump.

* Explanation of symbols for main parts of the drawings

10: compressor 20: 4-way valve

30: heat exchanger for condensation 40: expansion mechanism

41,42,47: 1st, 2nd, 3rd capillary 43,45: 1st, 2nd bypass tube

44: check valve 46: on / off valve

50: heat exchanger for evaporation 60: electric heater

61 refrigerant tube 62 insulating material

63: heating wire 64: heat insulating material

71,72: First and second evaporation temperature sensor

In order to achieve the object of the present invention, one side of the four-way valve is in communication with the compressor, the other side of the four-way valve is in communication with the heat exchanger for condensation, the expansion mechanism is in communication with the heat exchanger for the condensation, The evaporation heat exchanger communicates with the expansion mechanism, and another side of the four-way valve communicates with the evaporation heat exchanger, and the compressor further communicates with the compressor after another side of the four-way valve. In the evaporation heat exchanger and the inlet of the compressor, respectively, the first and second evaporation temperature sensor is mounted, the electric heater for controlling the heating value by the temperature difference of the first and second evaporation temperature sensor for evaporation An evaporation temperature compensation device for a heat pump is provided, which is installed at the outlet side of the heat exchanger.

Hereinafter, the evaporation temperature compensation device of the heat pump according to the present invention will be described in detail based on the embodiment shown in the accompanying drawings.

Heat pump according to the present invention is installed on the outlet side of the heat exchanger for evaporating heat to change the power applied in accordance with the outside temperature to increase the evaporation temperature to an appropriate temperature of the refrigerant flowing into the expansion mechanism By suppressing overexpansion to increase the evaporation temperature, Figure 3 is a schematic view showing a refrigeration cycle of a heat pump equipped with such an evaporation temperature compensation device.

As shown in the drawing, in the refrigeration cycle apparatus for a heat pump according to the present invention, one side of the four-way valve 20 is coupled to the outlet of the compressor 10, and the other side of the four-way valve 20 is used for condensation. The heat exchanger 30 is connected, the condensation heat exchanger 30 is connected to the expansion mechanism 40, commonly referred to as a capillary tube, the evaporation heat exchanger 50 is connected to the expansion mechanism 40, And, after the evaporation heat exchanger 50, the electric heater 60 is connected, coupled to the other side of the four-way valve 20 to the outlet of the electric heater 60, the four-way valve 20 Another side of the) accumulator (not shown) is connected, the accumulator (not shown) is connected to the inlet of the compressor (10).

Here, as shown in FIG. 4, the expansion device 40 is connected to a first capillary tube 41 having a shorter length and a second capillary tube 42 relatively longer than the first capillary tube in series. The first bypass pipe 43 connected inlet at the inlet of the capillary tube 41 and connected to the inlet of the second capillary tube 42 is connected in parallel, and the first bypass pipe 43 is a refrigerant during heating operation. Check valve 44 is installed in series to prevent the reverse flow of the second, the second bypass pipe 45 for raising the temperature and pressure of the refrigerant passing through the condensation heat exchanger 30 to an appropriate level is It is provided in parallel between the inlet front side of the first bypass tube 43 and the outlet side of the second capillary tube 42.

The second bypass pipe 45 is provided with an on / off valve 46 for opening and closing the second bypass pipe 45 according to a predetermined set temperature at the inlet part thereof, while the first capillary pipe ( A third capillary tube 47 shorter than the length of 41 is mounted.

Meanwhile, first and second evaporation temperature sensors (hereinafter, mixed with the first and second sensors) 71 and 72 are mounted at the inlets of the evaporation heat exchanger 50 and the compressor 10, respectively. The amount of power applied to the electric heater is determined by the difference between the first and second sensors 71 and 72.

As shown in FIG. 5, the electric heater is coated with an insulating material 62 such as asbestos on the outer circumferential surface of the refrigerant pipe 61 communicating between the compressor 10 and the evaporator 50, and the insulating material 62. Heating wires 63 such as coils are wound on the outer circumferential surface of a plurality of times, and the heat insulating material 64 is wrapped on the outer circumferential surface of the heating wires 63.

In the drawings, the same reference numerals are given to the same parts as in the prior art.

In the drawings, reference numeral 31 denotes an indoor fan and 51 denotes an outdoor fan.

In the refrigeration cycle apparatus of the heat pump according to the present invention configured as described above, the flow of a common refrigerant when the refrigeration cycle apparatus is used for heating is as follows.

That is, according to the operation of the compressor, the refrigerant is supplied to the compressor 10-four-way valve 20-condenser 30-expansion mechanism 40-evaporator 50-electric heater 60-four-way valve 20- Accumulator (not shown)-It proceeds through the sequence of the compressor (10) is to discharge the hot air heat exchanged in the condenser 30 to the indoor side sirocco fan 31 to maintain the heating state.

Here, when the temperature of the refrigerant evaporated in the evaporation heat exchanger 50 is greater than the temperature difference set in the first and second evaporation temperature sensors 71 and 72 as the temperature of the outside air decreases, the electric heater 60 Electric power is applied to the refrigerant, and the refrigerant passing through the evaporation heat exchanger 50 is heated by the applied electric power to rise to a predetermined temperature.

The refrigerant is detected again by the second sensor 72 installed at the compressor inlet before entering the compressor to determine whether the refrigerant has risen to a temperature suitable for heating while comparing with the temperature of the refrigerant detected by the first sensor 71. The amount of power applied to the electric heater is to be controlled.

The refrigerant risen to a predetermined temperature through this process is compressed to a high temperature and high pressure in the compressor (10) to flow into the condensation heat exchanger (30), the refrigerant introduced into the condensation heat exchanger (30) is a heat exchange to the room It will supply hot air.

On the other hand, when the temperature of the outside air drops sharply, the on / off valve 46 is opened to open the second bypass pipe 45. At this time, the temperature of the refrigerant passing through the condensation heat exchanger 30 and The pressure begins to drop in accordance with the temperature of the outside air and flows into the second bypass pipe 45 having the least resistance, and the refrigerant introduced into the second bypass pipe 45 includes the first and second capillary tubes ( 41, 42 is skipped and expanded while passing through the third capillary 47, and is introduced into the heat exchanger 50 for evaporation.

As a result, a much larger amount of refrigerant flows into the compressor 10 through the evaporation heat exchanger 50 than when passing through the first and second capillaries 41 and 42, as shown in FIG. 6. The pressure of the refrigerant compressed at 10 and the temperature thereof increase, and thus the high temperature refrigerant flows into the heat exchanger 30 for condensation, thereby increasing the temperature of the warm air supplied to the room.

As described above, the apparatus for compensating the evaporation temperature of a heat pump according to the present invention includes first and second evaporation temperature sensors respectively installed at the inlet of the evaporator heat exchanger and the compressor, and the first and second evaporation temperatures. An electric heater whose heating value is controlled by the temperature difference of the sensing sensor is installed at the outlet side of the evaporating heat exchanger, and an expansion mechanism is provided to increase the specific volume of the refrigerant according to the temperature of the outside air, thereby evaporating the refrigerant in the evaporating heat exchanger. The temperature and the specific volume of the refrigerant flowing into the compressor are prevented from being excessively lowered so that the hot air of a proper temperature is always supplied from the heat exchanger for condensation into the room, and the cost increase of the consumer is excluded by eliminating the use of a separate auxiliary heating device. There is an effect that can be prevented.

Claims (3)

After the compressor, one side of the four-way valve is in communication, the other side of the four-way valve is in communication with the condensation heat exchanger, the expansion mechanism is in communication with the condensation heat exchanger, and the evaporation heat exchanger is in communication with the expansion mechanism. In the refrigeration cycle of the heat pump in which the other side of the four-way valve is in communication with the evaporating heat exchanger, the compressor is again in communication with another side of the four-way valve, the inlet of the evaporating heat exchanger and the compressor The first and second evaporation temperature sensor is mounted to each of the parts, characterized in that the electric heater is controlled at the outlet side of the heat exchanger for evaporation heat is controlled by the temperature difference between the first and second evaporation temperature sensor Evaporating temperature compensation device of heat pump. According to claim 1, wherein the electric heater is coated with an insulating material on the outer peripheral surface of the refrigerant pipe that communicates between the compressor and the heat exchanger for evaporation, the heating wire wound around the outer peripheral surface of the insulating material a plurality of times, the heat insulating material on the outer peripheral surface of the heating wire Evaporating temperature compensation device of the heat pump, characterized in that the wrap is configured. The method of claim 1, wherein the expansion mechanism is connected to the first capillary, the second capillary tube relatively longer than the first capillary in series, branched from the inlet of the first capillary and connected to the inlet of the second capillary On the other hand, the first bypass pipe provided with a check valve for preventing the reverse flow of the refrigerant in the middle portion communicates in parallel, and the second bypass pipe is connected between the inlet front side of the first bypass pipe and the outlet side of the second capillary pipe. The on / off valve is connected in parallel and is opened and closed at a predetermined set temperature at the inlet of the second bypass tube, and a third capillary tube shorter than the length of the first capillary tube is mounted at the middle portion thereof. Evaporating temperature compensation device of the heat pump, characterized in that configured.

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