KR950009052B1 - Airconditioner - Google Patents

Abstract

When the surface temp. of a refrigerant evaporator(43), which is detected by a surface temp. sensor(63), is lowered to a temp. lower than a first set temp. during room cooling operation, the circulation pump(52) of a hot water circuit(5) is operated and a frequency for a refrigerant compressor(41) is reduced to heat the surface of the refrigerant evaporator(43) without stopping the operation of the refrigerant compressor(41). When the surface temp. of a refrigerant evaporator(43), which is detected by the surface temp. sensor(63), is reduced to a temp. lower than a second set temp. than the first set temp., the operation of the refrigerant compressor(41) is stopped whereby the repetition of starting, operating and stopping of the refrigerant compressor(41) can prevented. The feeling of room cooling is improved, and the refrigerant compressor is prevented from the deterioration of durability thereof.

Description

Air conditioner

1 is a schematic view showing the overall structure of a heating and cooling device as an air conditioner according to the present invention.

2 is a block diagram showing the main control device of the air conditioning and heating device shown in FIG.

3 and 4 are flowcharts showing the freezing prevention control of the computer shown in FIG.

* Explanation of symbols for main parts of the drawings

1: Air conditioning unit (air conditioner) 2: Blowing casing

4: refrigeration cycle 5: hot water circuit

6: computer (control means) 6a: speed control unit

41: refrigerant compressor 43: refrigerant evaporator

51: hot water heater (hot water radiator) 52: circulation pump (supply means)

The present invention relates to an air conditioner including a refrigerant evaporator for cooling and a radiator for hot water for heating in a blower casing of an indoor unit.

Conventionally, a refrigerant evaporator of a refrigeration cycle, a radiator for hot water of a hot water circuit, and a convection fan for circulating air in an indoor unit are disposed in a blower casing of an indoor unit to operate a refrigerant compressor disposed in an outdoor unit to perform indoor cooling while being disposed in an outdoor unit. There is a cooling and heating device for heating indoor water by heating hot water passing through the used outdoor heat exchanger by combustion heat such as a burner and operating a circulation pump. According to such a cooling and heating device, during the cooling operation, if the surface temperature of the refrigerant evaporator is considerably lowered, the amount of air blown into the room is lowered due to freezing between the fins of the refrigerant evaporator, thereby significantly lowering the cooling capacity.

In order to solve this problem, the conventional air conditioner is to stop the operation of the refrigerant compressor when the temperature of the refrigerant evaporator is lower than the set temperature during the cooling operation.

In the conventional air conditioners, however, the operation of the refrigerant compressor is stopped when the temperature of the refrigerant evaporator drops below the set temperature. Thus, the desired temperature is maintained by repeatedly starting and stopping the refrigerant compressor during the cooling operation. Iii) there is a problem that the cooling feeling of the user is lowered because it is not easily approached.

In addition, in the refrigerant compressor, since a large impact is applied to the valve parts such as the intake valve and the discharge valve at the start, when the refrigerant compressor is repeatedly started and stopped, there is a problem in that the consumption of the valve parts becomes severe and the durability decreases.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide an air conditioner which is designed to improve a feeling of cooling and prevent degradation of durability of a refrigerant compressor.

In order to achieve the above object, according to the present invention, a blow casing for blowing air into the room, and a refrigerant evaporator and a refrigerant to cool the air by heat-exchanging a refrigerant flowing through the inside and the air flowing through the blow casing A hot water circuit having a refrigeration cycle having a refrigerant compressor for discharging, a hot water radiator for heat-exchanging air by heat-exchanging the air flowing in the blower casing and the hot water flowing therein, and a supply means for supplying hot water to the hot water radiator; A temperature sensor for detecting the temperature of the refrigerant evaporator to operate the supply means when the temperature of the refrigerant evaporator detected by the temperature sensor during the operation of the refrigerant compressor drops below a first set temperature; The temperature of the refrigerant evaporator detected by the sensor is lowered below the second set temperature lower than the first set temperature The technical means provided with a control means for stopping the operation of the refrigerant compressor Yiwu is employed.

Here, the control means is provided with a rotation speed control unit for reducing the rotation speed of the refrigerant compressor when the node of the refrigerant evaporator is raised above the second set temperature, and lowered below the first set temperature.

According to the present invention having the above-described configuration, when the temperature of the refrigerant evaporator detected by the temperature sensor during the cooling operation in which the refrigerant compressor is operated falls below the first set temperature, the external air temperature is activated by operating the supply means of the hot water circuit. Hot water raised to the vicinity is supplied into the radiator for hot water, thereby warming the surface of the refrigerant evaporator.

In addition, even when the surface of the refrigerant evaporator is warmed as described above, the operation of the refrigerant compressor is stopped when the temperature of the refrigerant evaporator is further lowered to be below the second set temperature lower than the first set temperature.

As a result, freezing of the surface of the refrigerant evaporator can be reliably prevented, and the repetition of starting and stopping of the refrigerant compressor is reduced.

In addition, the present invention is to reduce the number of revolutions of the refrigerant compressor by the rotation speed control unit when the temperature of the refrigerant evaporator is higher than the second set temperature and lower than the first set temperature at the time of simultaneous operation of the refrigerant compressor and the supply means The loss of energy incurred in is suppressed.

Hereinafter, an air conditioner of the present invention will be described based on an embodiment shown in the accompanying drawings.

1 is a schematic view showing the overall structure of a cooling and heating device employed as an air conditioner of the present invention, wherein the cooling and cooling device 1 includes a blow casing 2 with a convection fan 3, a refrigeration cycle 4, and a hot water circuit ( 5) and a computer 6 (see FIG. 2), which is divided into an indoor unit 7 arranged indoors of its components and an outdoor unit 8 arranged outdoors.

The air blowing casing 2 is installed in the indoor unit 7, and at one end thereof, an inlet 21 for suctioning indoor air is provided, and the other end is provided with a blower outlet 22 for blowing air flow into the room.

The convection fan 3 is installed in the blow casing 2, and during operation (on), it generates an air flow toward the inside of the blow casing 2. This convection fan 3 is controlled by the air volume of any one of a strong wind, a weak wind, or a breeze.

The refrigeration cycle 4 is composed of a refrigerant compressor 41, a refrigerant compressor 42, a refrigerant evaporator 43, and a refrigerant pipe 44 connecting the components in an annular form as a cycle. .

The refrigerant compressor 41 is a type in which the rotation speed is changed by the frequency. The refrigerant compressor 41 compresses the refrigerant sucked into the compression chamber (not shown) from the refrigerant evaporator 43 when the suction valve (not shown) is opened. ) Is discharged to the refrigerant condenser 42 side.

The refrigerant condenser 42 condenses the refrigerant by heat-exchanging the refrigerant introduced into the outside air blown by the electric fan 45.

The refrigerant evaporator 43 heats the refrigerant introduced into the interior air and the indoor air blown by the convection fan 3 to evaporate the refrigerant and simultaneously cool the indoor air.

The hot water circuit 5 is constituted by a hot water heater 51, an electric circulation pump 52, an outdoor heat exchanger 53, and a hot water pipe 54 which annularly connects the components thereof. Antifreeze is used as warm water of (5).

The hot water heater 51 acts as a radiator for hot water in the present invention and heats the indoor air by heat-exchanging the indoor air blown by the convection fan 3 introduced into the hot water. The hot water heater 51 is installed in the blowing casing 2 downstream of the refrigerant evaporator 43, and some of the fins of the hot water heater 51 and the fin of the refrigerant evaporator 43 are commonly used.

While the circulation pump 52 acts as a supply means in the present invention and is installed in the outdoor unit 8 and is energized (ON), the circulation pump 52 generates hot water circulation in the hot water circuit 5 to supply hot water to the hot water heater 51. When the energization is stopped (OFF), the supply of hot water to the hot water heater 51 is stopped.

The outdoor heat exchanger 53 heats the hot water by heat-exchanging the combustion heat of the gas burner 55 installed in the outdoor unit 8 with the hot water introduced therein.

The gas burner 55 performs combustion of a mixer in which fuel gas supplied from the gas supply pipe 56 and combustion air supplied by the combustion fan 57 are mixed. The gas supply pipe 56 includes a switching unit (not shown) for switching the combustion state of the gas burner 55 to a plurality of stages between a strong combustion state and a weak combustion state. According to the combustion state of the burner 55, the blowing amount of the combustion fan 57 is also switched to a plurality of stages.

2 is a block diagram showing the main control device of the air conditioner (1).

As the control means of the present invention, the computer 6 receives the outputs of the operation switch 61, the mode changeover switch 62, the surface temperature sensor 63, and the like, and the convection fan 3, the refrigerant compressor 41, and the electric motor. The fan 45, the circulation pump 52, and the combustion fan 57 control the energization (ON) and stop of the energization (OFF), and at the same time control the combustion amount of the gas burner (55). In addition, when the computer 6 simultaneously operates the refrigerant compressor 41 and the circulation pump 53 in accordance with the freeze prevention operation described below, the frequency of the refrigerant compressor 41 is reduced to reduce the amount of energization. The rotation speed control part 6a which reduces the rotation speed of the compressor 41 is provided.

The operation switch 61 acts as a start switch of the air conditioning and heating device 1 so that the power source and each electric device are electrically connected.

Mode switching switch 62 is a switch for switching the air conditioning mode of the room, the cooling switch 64 for selecting the cooling operation mode, the heating switch 65 for selecting the heating operation mode and the dry switch for selecting the dry operation mode ( 66).

The cooling switch 64 is a switch for turning on the convection fan 3, the refrigerant compressor 41, and the electric fan 45 so as to be switched to a cooling operation mode for cooling the room.

The heating switch 65 turns the convection fan 3, the circulation pump 52, and the combustion fan 52 ON to burn the mixer by the gas burner 55 to a heating operation mode for heating the room. Switch to switch. The dry switch 66 turns on the convection fan 3, the refrigerant compressor 41, the electric fan 45, the circulation pump 52, and the combustion fan 57 to turn on the mixer by the gas burner 55. It is a switch that switches to the dry operation mode in which the room is dehumidified and heated by burning.

For example, the surface temperature sensor 63 uses a thermistor and is directly attached to the pin of the refrigerant evaporator 43 to detect the surface temperature of the refrigerant evaporator 43.

3 and 4 are flowcharts showing the freezing prevention control of the computer 6 shown in FIG.

First, it is initially determined whether the cooling switch 64 is in an ON state (step S1).

If the cooling switch 64 is not in the ON state as a result of the determination of step S1, the control of step S1 is repeated, whereas if the cooling switch 64 is in the ON state as a result of the determination of step S1, the surface is The surface temperature Te of the refrigerant evaporator 43 is read from the temperature sensor 63 (step S2), and the surface temperature Te of the refrigerant evaporator 43 is the first set temperature Ts1, for example, 2 ° C. In step S3, it is determined whether or not the state (Te?

If the surface temperature of the refrigerant evaporator 43 is not lowered below the first set temperature as a result of the determination of step S3, the control of step S1 is performed while the surface temperature of the refrigerant evaporator 43 is the first as a result of the determination of step S3. When the temperature falls below the set temperature, it is determined whether the circulation pump 52 is in an ON state (step S4).

As a result of the determination in step S4, when the circulation pump 52 is in the ON state, the control proceeds to the control of step S14, whereas when the circulation pump 52 is in the OFF state, the first set temperature Ts1 is YES. For example, it is determined whether or not the first predetermined time (Δt1: for example, 2 minutes) has elapsed in the state of being lowered to 2 ° C or lower (step S5).

If the first set time has not elapsed as a result of the determination of step S5, then control of step S8 is performed, whereas when the first set time elapses, the circulation pump 52 is turned on (step S6) and the refrigerant compressor ( 41 to decrease the frequency to (step S7), and if the surface temperature Te of the refrigerant evaporator 43 is lowered below the second set temperature Ts2 (for example, 0 ° C) lower than the first set temperature (Te≤ Ts2) It is judged (step S8).

As a result of the determination in step S8, if the surface temperature of the refrigerant evaporator 43 does not fall below the second set temperature, it is determined whether the circulation pump 52 is turned on (step S9). As a result of the determination in step S9, when the circulation pump 52 is in the OFF state, control of step S1 is performed, while control of step S14 is performed when the circulation pump 52 is ON.

When the surface temperature of the refrigerant evaporator 43 drops below the second set temperature as a result of the determination in step S8, it is determined whether the refrigerant compressor 41 is turned off (step S10).

If the refrigerant compressor 41 is in the OFF state as a result of the determination in step S10, the control of step S14 is performed, while in the ON state of the refrigerant compressor 41, the surface temperature of the refrigerant evaporator 43 is set to the second setting. It is determined whether or not the second set time (ΔT2: for example, 3 minutes) has elapsed after the temperature (Ts2: for example, 0 ° C) or lower has been lowered (step S11).

As a result of the determination in step S11, when the second set time has not elapsed, control of step S1 is performed, whereas when the second set time has elapsed, the refrigerant compressor 41 is turned off (step S12), and the refrigerant compressor ( It is determined whether or not the waiting time (for example, 3 minutes) has elapsed since 41) is turned off (step S13).

If the waiting time has not elapsed as a result of the determination of step S13, the control of step S13 is repeated, whereas if the waiting time has elapsed, the surface temperature Te of the refrigerant evaporator 43 is determined from the surface temperature sensor 63. It is read (step S14), and it is judged whether the surface temperature Te of the refrigerant evaporator 43 has risen above the third set temperature (Ts3: for example, 2 ° C) (Te? Te3) (step S15). .

If the surface temperature of the refrigerant evaporator 43 has not risen above the third set temperature as a result of the determination in step S15, the process returns to step S3 to perform subsequent control while the surface temperature of the refrigerant evaporator 43 is set to zero. When the temperature rises above the third set temperature, the refrigerant compressor 41 is turned on (step S16). Then, the fourth set temperature Ts4 where the surface temperature Te of the refrigerant evaporator 43 is higher than the third set temperature is YES. For example, it is determined whether the temperature rises above 3 ° C (Te≤Ts4) (step S17).

If the surface temperature of the refrigerant evaporator 43 does not rise above the fourth set temperature as a result of the determination in step S17, the control of step S14 is performed while the surface temperature of the refrigerant evaporator 43 is above the fourth set temperature. When it rises, after turning off the circulation pump 52 (step S18), it will return to control of step S1.

The operation of such a heating and cooling device 1 will be described based on FIGS. 1 to 3.

When the cooling switch 64 of the mode changeover switch 62 is selected, the computer 6 turns on the convection fan 3, the refrigerant compressor 41, and the electric fan 45 to turn on the refrigerant evaporator 43. The refrigerant is discharged from the compressor 41.

For this reason, the surface temperature of the refrigerant evaporator 43 is lowered by the heat exchange between the air passing between the fins of the refrigerant evaporator 43 and the refrigerant flowing inside the refrigerant evaporator 43.

When the surface temperature of the refrigerant evaporator 43 decreases considerably after a predetermined time has elapsed since the start of the cooling operation mode, the air passing between the fins of the refrigerant evaporator 43 contacts and cools the water in the air. This adheres and adheres to the surface of the pin. In addition, when the surface temperature Te of the refrigerant evaporator 43 is lowered to the freezing point or less while water droplets are attached to the surface of the fin, the surface of the fin freezes and blocks between the fins, so that the heat resistance and ventilation of the refrigerant evaporator 43 are prevented. The resistance increases.

Therefore, in the air conditioner (i.e., the air conditioner 1) of the present invention, the surface temperature of the refrigerant evaporator 43 is lowered below the first set temperature (e.g. For example, when 2 minutes elapse, the gas burner 55 turns on only the circulating pump 52 in the non-operation state, and the hot water (for example, 30 ° C. in which the water temperature is close to the outside temperature) is turned on. Will be supplied. At this time, the refrigerant compressor 41 and the circulation pump 52 are operated at the same time by turning on the circulation pump 52, and the power consumption is increased accordingly, so the refrigerant compressor 41 is operated by the operation of the rotation speed control unit 6a. By decreasing the frequency for), the amount of current supplied to the refrigerant compressor 41 is reduced, thereby reducing the rotation speed.

For this reason, the amount of circulation of the refrigerant in the refrigerating cycle 14 is reduced, so that the amount of cooling of the air in the refrigerant evaporator 43 is suppressed, and the fins of the refrigerant evaporator 43 installed in parallel with the hot water heater 51 are connected to the hot water heater ( It is warmed by the heat transfer from the pin of 51).

That is, the fin of the refrigerant evaporator 43 is heated by the heat of retention of the warm water heated up to the outside air temperature supplied into the hot water heater 51, thereby preventing freezing of the surface of the fin of the refrigerant evaporator 43. In addition, power consumption is also reduced, reducing costs.

Therefore, since the first set temperature (for example, 2 ° C) is set higher than the second set temperature (for example, 0 ° C) for turning off the refrigerant compressor 41 (for example, 0 ° C). Since the surface temperature of the refrigerant evaporator 43 decreases below the second set temperature (for example, 0 ° C.) at which the refrigerant compressor 41 is turned off, the refrigerant compressor 41 repeatedly turns on and off. Less work As a result, the user's cooling feeling can be improved because the user is close to the desired room temperature and the room temperature is stabilized.

In addition, in the refrigerant compressor 41, the on / off cycle is less repeated. In addition, after the refrigerant compressor 41 is turned off, the safety timer (not shown) is operated only for the waiting time (for example, 3 minutes), and the off state of the refrigerant compressor 41 is continued. As a result, the number of shocks applied to valve parts such as the intake valve and the discharge valve is reduced, and the consumption of valve parts such as the intake valve and the discharge valve is suppressed, so that the durability of the refrigerant compressor 41 can be improved.

Further, in the form in which the fin of the refrigerant compressor 43 and the fin of the hot water heater 51 are connected, when the surface of the fin of the refrigerant evaporator 43 is frozen, the hot water in the hot water heater 51 is also frozen. In the air conditioner (1) to which the present invention is applied, when the surface temperature of the refrigerant evaporator (43) falls below the first set temperature, the circulation pump (52) is turned on to generate a circulation flow in the hot water circuit (5). The problem that the hot water in the heater 51 is frozen can be solved.

On the other hand, when the refrigerant compressor 41 and the circulation pump 52 are operated simultaneously in the above-described setting, the frequency of the refrigerant compressor 41 is decreased to reduce the rotation speed, but the refrigerant compressor 41 and the circulation pump 52 are reduced. In the case of simultaneous operation, the amount of current supplied to the refrigerant compressor 41 may be lowered to reduce the rotation speed. In addition, it is not necessary to reduce the rotation speed of the refrigerant compressor 41 during the simultaneous operation of the refrigerant compressor 41 and the circulation pump 52.

In this embodiment, the temperature sensor 63 is used as the temperature sensor to control the surface temperature of the refrigerant evaporator 43. However, the temperature is controlled by the detection value of the surface temperature sensor 63. Hot water temperature sensor for detecting the temperature of hot water in the hot water circuit (5), surface temperature sensor for detecting the surface temperature of the hot water pipe (54) in the blowing casing (2), withdrawal temperature for detecting the extraction temperature of the refrigerant evaporator (43) A sensor or the like may be used to control the correlation between the detection values of the sensors and the surface temperature of the refrigerant evaporator 43.

For example, when the hot water temperature in the hot water pipe 54 near the refrigerant evaporator 43 detected by the hot water temperature sensor continues for 10 minutes below the set temperature (for example, 2 ° C), the circulation pump 52 is turned on. You may also The set time for turning on the circulation pump 52 and turning off the refrigerant compressor 41 can be arbitrarily changed.

In the present embodiment, the refrigerant compressor 41 and the circulation pump 52 are electrically powered, but the refrigerant compressor 41 may also be driven by an internal combustion engine or the like in one of the refrigerant compressors. The refrigerant compressor 41 and the circulation pump 52 may be driven by the drive means.

The air conditioner 1 described in this embodiment is of a type of heating hot water by the heat of combustion of the gas burner 55, but may be of a type of combustion heat of a burner that burns liquid fuel or a type of heating hot water by heat of an electric heater. The hot water may be heated by the heat generated by the operation of the internal combustion engine using the cooling water of the internal combustion engine.

In the case of the hot water circuit configured to supply the cold water of the internal combustion engine into the hot water radiator, the circulation pump is always operated. When the temperature of the refrigerant evaporator 43 rises above the first set temperature, the hot water is supplied to the hot water radiator. The supply flow path is blocked to stop the supply of hot water to the hot water radiator, and when the hot water falls below the first set temperature, the valve is opened to install an on / off valve (supply means) for supplying hot water to the hot water radiator. There is a need.

As described above, the present invention can improve the cooling feeling of the user and also improve the durability of the refrigerant compressor.

In addition, energy loss can be suppressed even during simultaneous operation of the supply means of the refrigerant compressor of the present invention.

Claims (2)

(a) a blow casing (2) for blowing air in the room, (b) a coolant evaporator (43) and a coolant for cooling the air by heat-exchanging a refrigerant flowing through the inside of the blow casing (2) A refrigeration cycle (4) having a refrigerant compressor (42) for compressing and discharging, (c) a heat radiator (51) for heating air by heat-exchanging the air flowing in the blower casing (2) and the hot water flowing therein; (D) a hot water circuit (5) having a supply means (52) for supplying hot water to the radiator (51) for hot water, and (d) a temperature sensor (63) for detecting a temperature of the refrigerant evaporator (43), and When the temperature of the refrigerant evaporator 43 detected by the temperature sensor 63 during the operation of the refrigerant compressor 41 drops below the first set temperature, the supply means 52 is operated and the temperature sensor ( The temperature of the refrigerant evaporator 43 detected at 63 is lower than the second preset temperature lower than the first preset temperature. In the lower case, the air conditioner comprising a control means (6) for stopping the operation of the refrigerant compressor (41). 2. The control means (6) according to claim 1, wherein the control means (6) rotates with the refrigerant compressor (41) when the temperature of the refrigerant evaporator (43) rises above the second set temperature and falls below the first set temperature. Air conditioning device, characterized in that it has a rotation speed control unit (6a) to reduce.