JP2008281304A - Multi-room air conditioner - Google Patents

Abstract

A multi-room air conditioner capable of optimizing a refrigeration cycle is provided.
Indoor units 10a to 10c each having indoor heat exchangers 7a to 7c, indoor decompression devices 8a to 8c, and indoor heat exchanger temperature detecting means 9a to 9c for detecting the indoor heat exchanger temperature, and a compressor 1, an outdoor heat exchanger 2, a four-way valve 4, an outdoor pressure reducing device 3, an outdoor heat exchanger temperature detecting means 5 for detecting the temperature of the outdoor heat exchanger 2, and a discharge temperature detecting means 11 for detecting the discharge temperature of the compressor 1. The discharge temperature detected by the discharge temperature detection means 11 is the temperature detected by the outdoor heat exchanger temperature detection means 5 during the cooling operation, and the indoor heat exchanger temperature detection means The lowest value of the temperatures detected by 9a to 9c is used as the evaporating temperature, and the depressurization control is performed based on the deviation from the discharge temperature that optimizes the refrigeration cycle. Can Therefore, it is possible to keep the refrigeration cycle is always optimal.
[Selection] Figure 1

Description

  The present invention relates to a multi-room air conditioner.

As a conventional multi-room type air conditioner, there is one that keeps the refrigerant superheat degree of an indoor heat exchanger constant during cooling operation (for example, see Patent Document 1).
JP 60-108632 A

  However, in the configuration of the conventional multi-room air conditioner disclosed in Patent Document 1, the indoor heat exchanger keeps the refrigerant superheat degree constant during cooling operation, and the indoor heat exchanger maximizes performance. Although the indoor decompression device is adjusted to a decompression amount that can be exerted, there is no viewpoint of optimizing the refrigeration cycle, and there is a problem that the compressor enters a severe operating state.

  The present invention solves the above-described conventional problems, and provides a multi-room air conditioner capable of optimizing the refrigeration cycle while adjusting the indoor pressure reducing device so that the indoor heat exchanger can exert its maximum performance. The purpose is to provide.

  In order to solve the conventional problems, the multi-room air conditioner of the present invention includes an indoor heat exchanger, an indoor decompression device, and an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, respectively. A plurality of indoor units, a compressor, an outdoor heat exchanger, a four-way valve, an outdoor pressure reducing device, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, and a discharge for detecting the discharge temperature of the compressor An outdoor unit having a temperature detecting means, and the discharge temperature detected by the discharge temperature detecting means is a temperature detected by the outdoor heat exchanger temperature detecting means at the time of cooling operation as a condensation temperature, and the plurality of indoor heats The lowest temperature among the temperatures detected by the exchanger temperature detection means is used as the evaporation temperature, and pressure reduction control is performed based on the deviation from the discharge temperature that optimizes the refrigeration cycle. Or indoor load Even in the installed state to become room, since it is possible to recognize and reliably condensing temperature and low detection error evaporation temperature, it is possible to keep the refrigeration cycle at all times optimally.

  The multi-room air conditioner of the present invention includes a plurality of indoor units each having an indoor heat exchanger, an indoor decompression device, and an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, An outdoor heat exchanger, an outdoor heat exchanger, a four-way valve, an outdoor pressure reducing device, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, and an outdoor unit having a discharge temperature detecting means for detecting the discharge temperature of the compressor; The discharge temperature detected by the discharge temperature detecting means is the highest value among the temperatures detected by the plurality of indoor heat exchanger temperature detecting means during heating operation, and the outdoor heat exchanger temperature The temperature detected by the detection means is the evaporation temperature, and pressure reduction control is performed based on the deviation from the discharge temperature that optimizes the refrigeration cycle. In the installed state Be, since it is possible to recognize the reliable condensation temperature and low detection error evaporation temperature, it is possible to keep the refrigeration cycle at all times optimally.

  The multi-chamber air conditioner of the present invention can reliably recognize the condensation temperature and the evaporation temperature without using a pressure sensor, so that the refrigeration cycle can be optimized with an inexpensive specification and the compressor is in a severe operating state. You can always keep optimal without falling into.

  The first invention includes a plurality of indoor units each having an indoor heat exchanger, an indoor pressure reducing device, and an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, a compressor and an outdoor heat exchanger, A four-way valve, an outdoor pressure reducing device, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, and an outdoor unit having a discharge temperature detecting means for detecting the discharge temperature of the compressor. The discharge temperature detected by the detection means is the lowest temperature among the temperatures detected by the plurality of indoor heat exchanger temperature detection means, with the temperature detected by the outdoor heat exchanger temperature detection means being the condensation temperature during cooling operation. Evaporation temperature is controlled under reduced pressure based on the deviation from the discharge temperature that optimizes the refrigeration cycle. Even in installation conditions where there is a difference in elevation between indoor units or in a room with different indoor loads, it is ensured. Condensation temperature It is possible to recognize the low evaporation temperature of detection error and can keep the refrigeration cycle at all times optimally.

  A second invention includes a plurality of indoor units each having an indoor heat exchanger, an indoor decompression device, and an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, a compressor and an outdoor heat exchanger, A four-way valve, an outdoor pressure reducing device, an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger, and an outdoor unit having a discharge temperature detecting means for detecting the discharge temperature of the compressor. The discharge temperature detected by the detection means is the highest value among the temperatures detected by the plurality of indoor heat exchanger temperature detection means during the heating operation, and the temperature detected by the outdoor heat exchanger temperature detection means is the temperature detected by the outdoor heat exchanger temperature detection means. Evaporation temperature is controlled under reduced pressure based on the deviation from the discharge temperature that optimizes the refrigeration cycle. Even in installation conditions where there is a difference in elevation between indoor units or in a room with different indoor loads, it is ensured. Condensation temperature It is possible to recognize the low evaporation temperature of detection error and can keep the refrigeration cycle at all times optimally.

  In particular, the third invention has suction temperature detection means for detecting the suction temperature of the compressor of the first invention, and the discharge temperature detected by the discharge temperature detection means is a plurality of indoor heat exchangers during cooling operation. Comparing the lowest value of the temperatures detected by the temperature detection means with the suction temperature detected by the suction temperature detection means, based on the deviation from the discharge temperature that optimizes the refrigeration cycle with the lower value as the evaporation temperature Since the pressure is reduced, the condensation temperature and the evaporating temperature with little detection error can be recognized reliably even in installation conditions where there is a height difference between indoor units or in a room with different indoor loads. The cycle can always be kept optimal.

  In particular, the fourth aspect of the invention has suction temperature detection means for detecting the suction temperature of the compressor of the second invention, and the discharge temperature detected by the discharge temperature detection means detects the outdoor heat exchanger temperature during heating operation. The temperature detected by the means and the suction temperature detected by the suction temperature detection means are compared, and the pressure is reduced based on the deviation from the discharge temperature that optimizes the refrigeration cycle using a low value as the evaporation temperature. The refrigeration cycle can always be kept optimal because it can recognize the condensation temperature and the evaporation temperature with little detection error even in installations with different heights or installations in rooms with different indoor loads. Can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a refrigeration cycle diagram of a multi-room air conditioner according to a first embodiment of the present invention.

In FIG. 1, the multi-room air conditioner in the present embodiment includes an outdoor unit 6 and indoor units 10a, 10b, and 10c sequentially connected to the outdoor unit 6, and the outdoor unit 6 includes the compressor 1 and The outdoor heat exchanger 2, the outdoor pressure reducing device 3, and the four-way valve 4 for switching between heating and cooling, each of the indoor units 10 a, 10 b, and 10 c is exchanged with the indoor pressure reducing devices 8 a, 8 b, 8 c And 7a, 7b, 7c.

  5 is an outdoor heat exchanger temperature detection means attached to the outdoor heat exchanger 2, and detects the condensation temperature during cooling and the evaporation temperature during heating.

  Reference numerals 9a, 9b, and 9c denote indoor heat exchanger temperature detecting means that are attached to the indoor heat exchangers 7a, 7b, and 7c and detect the temperatures thereof. Reference numeral 11 denotes discharge temperature detecting means for detecting the discharge temperature of the compressor 1.

  The operation of the multi-room type air conditioner in the present embodiment configured as described above will be described below.

  During the cooling operation, the high-pressure gas refrigerant discharged from the compressor 1 of the outdoor unit 6 is heat-exchanged in the outdoor heat exchanger 2 and liquefied, passes through the outdoor decompression device 3, and is sent to the indoor units 10a, 10b, and 10c. It is done. In the indoor units 10a, 10b, and 10c, the pressure is reduced by the respective indoor pressure reducing devices 8a, 8b, and 8c, the heat is exchanged by the indoor heat exchangers 7a, 7b, and 7c, and the low pressure gas is converted into the compressor 1 again.

  At this time, the indoor decompression devices 8a, 8b, and 8c calculate the discharge temperature at which the refrigeration cycle is optimal from the condensation temperature and the evaporation temperature, and adjust the decompression amount from the deviation from the discharge temperature detected by the discharge temperature detecting means 11. However, the condensation temperature is the temperature detected by the outdoor heat exchanger temperature detecting means 5, and the evaporation temperature is the lowest value among the temperatures detected by the indoor heat exchanger temperature detecting means 9a, 9b, 9c. . Originally, the evaporating temperature is generally the saturation temperature of the suction pressure, but with such a configuration, the suction pressure sensor is used because it becomes a value close to the saturation temperature of the suction pressure as much as possible. It can always be set as the optimal refrigerating cycle.

  Next, heating operation by the multi-room air conditioner in the present embodiment will be described.

  During the heating operation, the high-pressure gas refrigerant discharged from the compressor 1 of the outdoor unit 6 is sent to the indoor units 10a, 10b, and 10c, and is liquefied by heat exchange in the indoor heat exchangers 7a, 7b, and 7c. It returns to the outdoor unit 6 through the devices 8a, 8b and 8c. In the outdoor unit 6, the pressure is reduced by the outdoor pressure reducing device 3, the heat is exchanged by the outdoor heat exchanger 2, the gas is converted into low pressure gas, and the flow returns to the compressor 1 again.

  Also in the heating operation, similarly to the cooling operation, the discharge temperature at which the refrigeration cycle is optimized is calculated from the condensation temperature and the evaporation temperature, and the deviation of the discharge temperature detected by the discharge temperature detecting means 11 is used for the outdoor decompression device 3. Although the amount of pressure reduction is adjusted, the condensation temperature is set to the highest value among the temperatures detected by the indoor heat exchanger temperature detecting means 9a, 9b, 9c, and the evaporation temperature is detected by the outdoor heat exchanger temperature detecting means 5. It is temperature.

  Originally, the condensing temperature is the saturation temperature of the discharge pressure, but by adopting the above-described configuration, the condensing temperature is surely condensed even in an installation state where there is a height difference between the indoor units 10a to 10c and an installation state in a room with different indoor loads. Since the temperature can be detected, an optimum refrigeration cycle can always be achieved without using a discharge pressure sensor.

(Embodiment 2)
FIG. 2 is a refrigeration cycle diagram of the multi-room air conditioner according to the second embodiment of the present invention. As shown in FIG. 2, the present embodiment is provided with suction temperature detecting means 12 for detecting the suction temperature of the compressor 1, and the other configuration is the multi-chamber air in the first embodiment. Since it is the same as a harmony machine, the same part is attached | subjected with the same code | symbol and the description is abbreviate | omitted.

  During the cooling operation of the multi-room air conditioner in the present embodiment, the indoor decompression devices 8a, 8b, and 8c calculate the discharge temperature at which the refrigeration cycle is optimized from the condensation temperature and the evaporation temperature, and detect the discharge temperature. The amount of pressure reduction is adjusted from the deviation from the discharge temperature detected by the means 11, the condensation temperature is the temperature detected by the outdoor heat exchanger temperature detecting means 5, and the evaporation temperature is the indoor heat exchanger temperature detecting means 9a, 9b. , 9c are compared with the lowest value detected by the suction temperature detecting means 12 to obtain a low value.

  With the above-described configuration, since the value becomes as close as possible to the saturation temperature of the suction pressure under any operating condition, the optimum refrigeration cycle can always be achieved without using the suction pressure sensor.

  Further, during the heating operation, the discharge temperature at which the refrigeration cycle is optimized is calculated from the condensation temperature and the evaporation temperature, and the pressure reduction amount of the outdoor pressure reducing device 3 is adjusted from the deviation from the discharge temperature detected by the discharge temperature detecting means 11. However, the condensation temperature is set to the highest value among the temperatures detected by the indoor heat exchanger temperature detecting means 9a, 9b, 9c, and the evaporating temperature is detected by the outdoor heat exchanger temperature detecting means 5 and the suction temperature detection. The suction temperature detected by the means 12 is compared and set to a low value.

  With the above configuration, the condensing temperature is as close as possible to the saturation temperature of the discharge pressure and the evaporation temperature is as close as possible to the saturation temperature of the suction pressure under any operating conditions and installation conditions. It is always possible to achieve an optimum refrigeration cycle.

  The multi-room type air conditioner according to the present invention is an inexpensive specification without using a pressure sensor because it controls the decompression of the indoor unit by using the lowest value of the plurality of indoor heat exchanger temperatures as an evaporating temperature input during cooling operation. It can provide a comfortable space at all times, and can be applied to various multi-room air conditioners for home use and business use.

Refrigeration cycle diagram of the multi-room air conditioner in Embodiment 1 of the present invention Refrigeration cycle diagram of multi-room air conditioner according to Embodiment 2 of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Outdoor heat exchanger 3 Outdoor decompression device 4 Four-way valve 5 Outdoor heat exchanger detection means 6 Outdoor unit 7a, 7b, 7c Indoor heat exchanger 8a, 8b, 8c Indoor decompression device 9a, 9b, 9c Indoor heat exchange Chamber temperature detection means 10a, 10b, 10c Indoor unit 11 Discharge temperature detection means 12 Suction temperature detection means

Claims (4)

A plurality of indoor units each having an indoor heat exchanger, an indoor pressure reducing device, and an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, a compressor, an outdoor heat exchanger, a four-way valve, and an outdoor pressure reducing device And an outdoor unit having an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger and a discharge temperature detecting means for detecting the discharge temperature of the compressor, and the discharge detected by the discharge temperature detecting means A refrigeration cycle in which the temperature detected by the outdoor heat exchanger temperature detecting means during the cooling operation is a condensation temperature, and the lowest value among the temperatures detected by the plurality of indoor heat exchanger temperature detecting means is an evaporation temperature. The multi-room air conditioner is characterized in that pressure reduction control is performed based on a deviation from the discharge temperature so as to optimize the temperature. A plurality of indoor units each having an indoor heat exchanger, an indoor pressure reducing device, and an indoor heat exchanger temperature detecting means for detecting the temperature of the indoor heat exchanger, a compressor, an outdoor heat exchanger, a four-way valve, and an outdoor pressure reducing device And an outdoor unit having an outdoor heat exchanger temperature detecting means for detecting the temperature of the outdoor heat exchanger and a discharge temperature detecting means for detecting the discharge temperature of the compressor, and the discharge detected by the discharge temperature detecting means The refrigeration cycle is such that, during the heating operation, the highest value among the temperatures detected by the plurality of indoor heat exchanger temperature detecting means is the condensation temperature, and the temperature detected by the outdoor heat exchanger temperature detecting means is the evaporation temperature. The multi-room air conditioner is characterized in that pressure reduction control is performed based on a deviation from the discharge temperature so as to optimize the temperature. A suction temperature detection means for detecting the suction temperature of the compressor, and the discharge temperature detected by the discharge temperature detection means is the lowest value among the temperatures detected by the plurality of indoor heat exchanger temperature detection means during cooling operation; 2. The pressure reduction control is performed based on a deviation from a discharge temperature at which the refrigeration cycle is optimized by comparing the suction temperature detected by the suction temperature detecting means with a low value as an evaporation temperature. Multi-room air conditioner. It has suction temperature detection means for detecting the suction temperature of the compressor, and the discharge temperature detected by the discharge temperature detection means is detected by the outdoor heat exchanger temperature detection means and the suction temperature detection means during heating operation. The multi-chamber air conditioner according to claim 2, wherein the reduced-pressure control is performed on the basis of a deviation from a discharge temperature at which the refrigeration cycle is optimized by using a low value as an evaporating temperature and comparing with the suction temperature. .

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