Air conditioning system

Abstract

To provide an air conditioner capable of suppressing an increase in power consumption while maintaining a certain degree of comfort.SOLUTION: The air conditioner includes an indoor unit, an outdoor unit, a refrigerant pipe, a compressor, an expansion valve, and a control part. The control unit is capable of executing a normal operation mode in which normal operation control is executed in which conditioned air is blown out from the indoor unit by controlling the operating frequency of the compressor in accordance with a set temperature set in the indoor unit and a room temperature of a room in which the indoor unit is installed, and a weak operation mode in which constant speed operation control is executed in which conditioned air is blown out from the indoor unit by controlling the operating frequency of the compressor so as to be constant at an operating frequency lower than a maximum operating frequency in the normal operation control, the weak operation mode being settable by a user, when the setting of the weak operation mode is released after the setting of the weak operation mode, the operation mode is shifted to the normal operation mode.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an air conditioner.

Background Art

[0002] An air conditioner such as an air conditioner adjusts the indoor temperature by heat release and heat absorption due to condensation and evaporation of a refrigerant in a refrigeration cycle. For example, in the cooling operation, the refrigerant condenses in an outdoor heat exchanger (condenser) and evaporates in an indoor heat exchanger (evaporator). Also, in the heating operation, the refrigerant evaporates in an outdoor heat exchanger (evaporator) and condenses in an indoor heat exchanger (condenser). Then, the conditioned air whose temperature is adjusted by heat exchange in the indoor heat exchanger is blown out from the indoor unit into the room, thereby adjusting the indoor temperature. In this case, the compressor that sends the refrigerant to the heat exchanger at high temperature and high pressure is controlled according to the difference between the set temperature for the indoor unit and the indoor temperature. And, for example, when the indoor temperature reaches the set temperature, the operation of the compressor is temporarily stopped (OFF), and then, when the indoor temperature deviates from the set temperature by a predetermined temperature or more, the operation of the compressor is restarted (ON). As a result, the indoor temperature is controlled to be maintained near the set temperature.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the control that repeatedly performs the ON / OFF operation of the compressor (the air conditioner) causes an increase in power consumption (electricity charges), which is not preferable in the operation of the air conditioner.

[0005] An example of the problem to be solved by the present invention is to provide an air conditioner that can suppress an increase in power consumption while maintaining a certain level of comfort. [Means for solving the problem]

[0006] An air conditioning system according to one embodiment of the present invention comprises an indoor unit, an outdoor unit, refrigerant piping, a compressor, an expansion valve, and a control unit. The indoor unit includes an indoor heat exchanger and an indoor fan. The outdoor unit includes an outdoor heat exchanger and an outdoor fan. The refrigerant piping connects the indoor heat exchanger and the outdoor heat exchanger, through which the refrigerant flows. The compressor is provided in the outdoor unit and compresses the refrigerant with a variable controllable operating frequency. The expansion valve is provided in the outdoor unit. The control unit performs air conditioning operation based on the refrigerant flow pattern. This control unit is capable of performing normal operation control, which controls the operating frequency of the compressor according to the set temperature set on the indoor unit and the room temperature in which the indoor unit is installed, thereby blowing out conditioned air from the indoor unit; and low-speed operation control, which controls the operating frequency of the compressor to be constant at an operating frequency lower than the maximum operating frequency in the normal operation control, thereby blowing out conditioned air from the indoor unit. The user can set the low-speed operation mode, and when the low-speed operation mode is set, Regardless of the airflow setting of the indoor fan, In the initial state of the constant-speed operation control, the airflow from the indoor fan is set to the minimum airflow as the default value, and during the execution of the constant-speed operation control, Based on the instructions of the aforementioned user The airflow from the indoor fan can be variably controlled, and if the low-speed operation mode is canceled after it has been set, the system will switch to the normal operation mode.

[0007] Furthermore, the control unit of the air conditioner may, for example, cancel the setting of the low-speed operation mode if the operation of the air conditioner is stopped after setting the low-speed operation mode.

[0008] Furthermore, the control unit of the air conditioner may, for example, switch to the low-speed operation mode if the low-speed operation mode is set while the normal operation mode is running.

[0009] Furthermore, the control unit of the air conditioning system may, for example, start the low-speed operation mode if it is set while the air conditioning system is stopped.

[0010] Furthermore, the control unit of the air conditioner may, for example, when the low-speed operation mode is set, the indoor heat exchanger functions as an evaporator, and the constant-speed operation control is being performed, and after a predetermined period of time since the execution of the constant-speed operation control, the room temperature is above the upper limit switching threshold temperature for switching the control state set in that case, switch the control state to the normal operation control, and after a predetermined period of time since the execution of the constant-speed operation control, the room temperature is below the lower limit stopping threshold temperature for stopping the control set in that case, stop the operation of the compressor.

[0011] Furthermore, the control unit of the air conditioner may, for example, when the low-speed operation mode is set, the indoor heat exchanger functions as a condenser, and the constant-speed operation control is being performed, and after a predetermined period of time since the execution of the constant-speed operation control the room temperature falls below the lower limit switching threshold temperature for switching the control state set in that case, switch the control state to the normal operation control, and after a predetermined period of time since the execution of the constant-speed operation control the room temperature is above the upper limit stopping threshold temperature for stopping the control set in that case, stop the operation of the compressor.

[0014] The above air conditioning system makes it possible to maintain a certain level of comfort while suppressing an increase in power consumption. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is an illustrative and schematic block diagram showing the general configuration of an air conditioning system according to an embodiment. [Figure 2] Figure 2 shows a schematic configuration of the indoor unit in the embodiment, as well as an illustrative and schematic cross-sectional view showing the state in which the air deflector is switched to the closed position. [Figure 3]Figure 3 shows a schematic configuration of the indoor unit in the embodiment, as well as an illustrative and schematic cross-sectional view showing the state in which the air deflector is switched to the open position. [Figure 4] Figure 4 is an exemplary and schematic perspective view showing the general external configuration of the indoor unit in the embodiment. [Figure 5] Figure 5 is an exemplary and schematic perspective view showing the appearance of the control terminal in the air conditioning system according to the embodiment. [Figure 6] Figure 6 is an illustrative diagram illustrating the difference in room temperature changes during normal operation control and constant-speed operation control in the air conditioning system according to this embodiment. [Figure 7] Figure 7 is an illustrative diagram illustrating the difference in operating capacity between normal operation control and constant-speed operation control during cooling operation in the air conditioning system according to this embodiment. [Figure 8] Figure 8 is an illustrative diagram showing the change in room temperature when the constant speed operation control and normal operation control switch during cooling operation when the low-speed operation mode is selected in the air conditioning system according to this embodiment. [Figure 9] Figure 9 is an illustrative diagram showing the change in room temperature when the constant speed operation control and control stop switch during cooling operation when the low-speed operation mode is selected in the air conditioning system according to this embodiment. [Figure 10] Figure 10 is an illustrative diagram showing the change in room temperature when the constant speed operation control and normal operation control switch during heating operation when the low-speed operation mode is selected in the air conditioning system according to this embodiment. [Figure 11] Figure 11 is an illustrative diagram showing the change in room temperature when the constant speed operation control and control stop switch during heating operation when the low-speed operation mode is selected in the air conditioning system according to this embodiment. [Modes for carrying out the invention]

[0016] Figure 1 is an illustrative and schematic block diagram showing the general configuration of an air conditioning system 1 according to an embodiment, which consists of an indoor unit 10 and an outdoor unit 120.

[0017] The air conditioner 1 includes an operation terminal 94a, an indoor unit 10, and an outdoor unit 120. The indoor unit 10 is arranged indoors, and the outdoor unit 120 is arranged outdoors. The operation terminal 94a receives an operation instruction from a living body CR (e.g., a user) existing indoors, and transmits a command to the indoor unit 10 according to the received operation instruction. The operation terminal 94a is, for example, a remote controller. Also, the operation terminal 94a may be an external terminal device 94b such as a smartphone or a tablet terminal device, or may be a personal computer or the like. The operation terminal 94a may transmit a command to the indoor unit 10 via a network or a server connected to the network. The operation terminal 94a may have a button for commanding a set temperature. The button for commanding the set temperature may be a physical button or a button of a display object displayed on the screen.

[0018] In this specification, the set temperature means the temperature commanded to the air conditioner 1 via the operation terminal 94a or the like. The target temperature means the temperature as a control target for the air sucked into the room by the air conditioner 1.

[0019] The indoor unit 10 includes a radar 2 (e.g., a living body sensor), an indoor unit control section 80, an up-down air direction plate 25, a left-right air direction plate 29, a room temperature sensor 3, etc. The outdoor unit 120 includes an outdoor unit control section 180. The indoor unit control section 80 and the outdoor unit control section 180 cooperate with each other to perform air conditioning processing according to the command received by the indoor unit 10 from the operation terminal 94a. That is, the indoor unit control section 80 and the outdoor unit control section 180 can execute air conditioning operation at the set temperature set by the user via the operation terminal 94a or the like. At the same time, the indoor unit control section 80 performs control using the radar 2. The living body CR is, for example, a person. In this case, the radar 2 may be a living body sensor or a human presence sensor.

[0020] The indoor unit control unit 80 has two air conditioning control modes for the indoor unit 10: a tracking air conditioning control mode and a normal air conditioning control mode. The tracking air conditioning control mode is an air conditioning control mode that supplies conditioned air to the person being tracked while tracking the biological CR using the radar 2. The normal air conditioning control mode is an air conditioning control mode that supplies conditioned air to the entire room fairly uniformly without tracking people.

[0021] On the other hand, the outdoor unit control unit 180 can execute a normal operation mode and a low-speed operation mode as operating control modes for the outdoor unit 120. The normal operation mode is an operating mode that performs normal operation control to blow out conditioned air from the indoor unit 10 by controlling the operating frequency of the compressor 125 according to the set temperature set on the indoor unit 10 and the room temperature in the room where the indoor unit 10 is installed. In the normal operation mode, for example, the operating frequency of the compressor 125 may be controlled according to the difference between the set temperature and the room temperature. The low-speed operation mode is an operating mode that performs constant-speed operation control to blow out conditioned air from the indoor unit 10 by controlling the compressor at a constant constant-speed operating frequency lower than the highest operating frequency possible in normal operation control, regardless of the room temperature. When the low-speed operation mode is selected by the Biological CR (user), the outdoor unit control unit 180 controls the system to maintain the constant-speed operation control for a predetermined period of time from the start of execution of the constant-speed operation control. Details of the low-speed operation mode will be described later.

[0022] Alternatively, the indoor unit control unit 80 may be primarily responsible for performing the air conditioning treatment. In that case, the outdoor unit 120 may be configured without the outdoor unit control unit 180.

[0023] In tracking air conditioning control mode, when performing cooling operation, the radar 2 detects the position of the living CR in the room under the control of the indoor unit control unit 80. The indoor unit control unit 80 tracks the position of the detected living CR and controls the vertical air deflector 25 and the horizontal air deflector 29 to move in the direction toward the position of the detected living CR. That is, it directs the vertical air deflector 25 and the horizontal air deflector 29 so that the air is directed toward the position of the living CR (mainly the living CR's body). At this time, the room temperature sensor 3 detects the temperature of the air in the room under the control of the indoor unit control unit 80. The air conditioning unit 1 performs cooling operation to bring the target temperature closer to the set temperature commanded by the operation terminal 94a, etc.

[0024] This allows the conditioned air from the indoor unit 10 to reach the biological CR even when it moves around the room, effectively lowering its perceived temperature. The tracking ability of the biological CR can be easily improved by using the detection results of the radar 2. In other words, the conditioned air can be directed to the biological CR in real time, making it less likely for comfort to be compromised. As a result, the comfort level of the biological CR present in the room can be dynamically improved.

[0025] In tracking air conditioning control mode, the control to direct the upper and lower air deflectors 25 and the left and right air deflectors 29 so that the airflow is directed towards the location of the biological CR may be precisely directed towards the location of the biological CR, or it may be approximately directed towards the location of the biological CR. For example, the control to direct the upper and lower air deflectors 25 and the left and right air deflectors 29 so that the airflow is directed towards the location of the biological CR may include, for example, dividing the room into 3 to 4 areas, identifying which area the biological CR is in, and sending airflow towards that area (a wide range). The control to direct the upper and lower air deflectors 25 and the left and right air deflectors 29 so that the airflow is directed towards the location of the biological CR may also include the control to swing the upper and lower air deflectors 25 and the left and right air deflectors 29 left and right within a range where the airflow does not deviate from the location of the biological CR.

[0026] In tracking air conditioning control mode, when performing heating operation, the radar 2 detects the position of the living CR in the room under the control of the indoor unit control unit 80, just as in cooling operation. In heating operation, the indoor unit control unit 80 tracks the position of the detected living CR and controls the vertical air deflector 25 and the horizontal air deflector 29 to move toward the position of the detected living CR's feet. In other words, the air deflector is directed so that the air is directed toward the position of the living CR's feet.

[0027] As a result, when a living CR (Cellular Receptor) moves around the room, the conditioned air from the indoor unit 10 reaches the CR's feet, effectively raising the CR's perceived temperature by warming it from the feet up. By using the detection results of the radar 2, the tracking ability of the living CR can be easily improved. In other words, the conditioned air can be delivered to the CR's feet in real time, making it less likely for comfort to be compromised. As a result, the comfort of living CRs in the room can be dynamically improved. Furthermore, even during heating operation, the same effect can be obtained by controlling the vertical air deflectors 25 and the horizontal air deflectors 29 to point them towards the precise location or approximately the location where the living CR is located, just as during cooling operation.

[0028] In normal air conditioning control mode, the air conditioning unit 1 performs cooling or heating operation at the set temperature commanded by the control terminal 94a, etc. At this time, the vertical air deflector 25 and the horizontal air deflector 29 may be fixed in the direction specified by the control terminal 94a, etc., or they may swing within a predetermined angular range.

[0029] The indoor unit 10 performs air conditioning treatment on the air drawn in from the room in which the indoor unit 10 is installed via the intake port, and blows the conditioned air back into the room. The air conditioning treatment includes, for example, heat absorption treatment, heating treatment, dehumidification treatment, humidification treatment, air blowing treatment, and air purification treatment. Heat absorption treatment, heating treatment, dehumidification treatment, humidification treatment, air blowing treatment, and air purification treatment correspond to the operating modes (main operating modes) of the air conditioning system 1: cooling operation mode, heating operation mode, dehumidification operation mode, humidification operation mode, air blowing operation mode, and air purification operation mode, respectively.

[0030] The main operating mode can be arbitrarily combined with the tracking air conditioning control mode and the normal air conditioning control mode described above. In tracking air conditioning control mode, the air conditioning unit 1 can take any of the following modes: cooling operation mode, heating operation mode, dehumidification operation mode, humidification operation mode, fan operation mode, or air purification operation mode. The same applies to the normal air conditioning control mode.

[0031] In air conditioning treatment, humidification treatment may be omitted. In this case, the humidification operation mode may be omitted as an operating mode of the air conditioning unit 1.

[0032] In air conditioning, dehumidification involves cooling the air taken in from the room, condensing the moisture in the air onto the surface of the heat exchanger 22 of the indoor unit 10, and releasing it outside, thereby bringing the humidity closer to the set level, for example, by performing cooling operation. There are two types of dehumidification: weak cooling dehumidification and reheat dehumidification. Weak cooling dehumidification returns the cooled air directly to the room to lower the humidity. Reheat dehumidification cools the air once to lower the humidity, performs dehumidification, and then reheats the air before returning it to the room. As a result, it is possible to lower the humidity without lowering the room temperature.

[0033] In air conditioning systems, the air circulation system circulates indoor air without changing its temperature or humidity. In other words, it takes in indoor air and then sends it back into the room, circulating the air within the room and providing comfort to the living environment.

[0034] Various methods can be applied to the air purification process; an electrostatic precipitation method or a fan method may be used. In the electrostatic precipitation method, dust is removed from the air by passing charged air through a filter and attracting the dust to a filter charged with the opposite polarity. In the fan method, air is passed through a fine-mesh filter such as a HEPA filter, and the dust is removed from the air by filtering it out. Alternatively, the air purification process may involve releasing ions into the air, or sterilizing the inside of the air conditioning unit 1 by irradiating it with ultraviolet (UV) light.

[0035] The air conditioning system 1 has two auxiliary air conditioning operation modes: "windless mode on" and "windless mode off." The auxiliary air conditioning operation modes can be arbitrarily combined with the aforementioned tracking air conditioning control mode and normal air conditioning control mode, and can also be arbitrarily combined with the main operation mode. When the windless mode is on, when air-conditioned air is blown out from the indoor unit 10, two types of airflow velocities are mixed to generate turbulent air that diffuses over a wide area, creating a natural breeze (a so-called windless breeze).

[0036] The air conditioner 1 may have an automatic operation mode as an operating mode. The air conditioner 1 detects the room temperature with a room temperature sensor 3. The room temperature sensor 3 is installed in a location where it can detect the air inside the room. The room temperature sensor 3 may be installed near the air intake and detect the temperature of the air being drawn into the intake from inside the room. In automatic operation mode, the air conditioner 1 can operate in cooling mode if the temperature detected by the room temperature sensor 3 is higher than the set temperature (automatic cooling threshold), and can operate in heating mode if the temperature detected by the room temperature sensor 3 is lower than the set temperature (automatic heating threshold).

[0037] As shown in Figure 1, the indoor unit 10 of the air conditioning system 1 includes a radar 2, an indoor unit control unit 80, a room temperature sensor 3, a heat exchanger 22 (indoor heat exchanger), a fan 23 (indoor blower fan), a filter 24 (described later), an up / down air deflector 25, a left / right air deflector 29, a ventilation member 26, a transmitting / receiving device 94, etc. The indoor unit 10 also includes a first drive circuit 81, a second control circuit 82, a third control circuit 83, and a fan motor 84, an up / down air deflector motor 85, a left / right air deflector motor 86, a switching motor 87, etc., all controlled by the indoor unit control unit 80. In the configuration shown in Figure 1, an example is shown in which an air purification unit 4 that performs an electrostatic dust collection method is controlled by the indoor unit control unit 80 as an air purification process.

[0038] The outdoor unit 120 also includes a heat exchanger 122 (outdoor heat exchanger), a fan 123 (outdoor blower fan), a four-way valve 124, a compressor 125, an outdoor unit control unit 180, a fourth drive circuit 181, a fifth drive circuit 182, a sixth drive circuit 183, a fan motor 184, a valve switching motor 185, a compressor motor 186, and the like.

[0039] In the indoor unit 10, the fan 23 is positioned near the heat exchanger 22. The fan 23 guides air drawn in from the room through the intake port of the indoor unit 10 to the heat exchanger 22, and also guides the conditioned air, which has undergone heat exchange in the heat exchanger 22, to the outlet port of the indoor unit 10. The indoor unit control unit 80 drives the fan motor 84 with the first drive circuit 81 to rotate the fan 23 around its rotation axis. The indoor unit control unit 80 can change the rotation speed of the fan 23.

[0040] The heat exchanger 22 can take on various configurations. For example, the heat exchanger 22 includes a plurality of fins and a refrigerant circuit (refrigerant piping RL) connected to them. The plurality of fins are in thermal contact with the refrigerant circuit, which passes nearby. The heat exchanger 22 exchanges heat with the refrigerant for the air drawn in from the room.

[0041] In the outdoor unit 120, the fan 123 is positioned near the heat exchanger 122. The fan 123 rotates in response to control by the outdoor unit control unit 180. As a result, the fan 123 draws in outside air and guides it to the heat exchanger 122, and also discharges the outside air that has undergone heat exchange in the heat exchanger 122 to the outside of the outdoor unit 120. The outdoor unit control unit 180 drives the fan motor 184 with the fourth drive circuit 181 to rotate the fan 123 around its axis. The outdoor unit control unit 180 can change the rotation speed of the fan 123.

[0042] The heat exchanger 122 can take on various configurations. For example, the heat exchanger 122 includes a plurality of fins and a refrigerant circuit connected to them. The plurality of fins are in thermal contact with the refrigerant circuit, which passes nearby. The heat exchanger 122 exchanges heat with the refrigerant and the outside air. In other words, the heat exchanger 22 and the heat exchanger 122 are connected by a refrigerant circuit (refrigerant piping RL), through which the refrigerant circulates.

[0043] The four-way valve 124 is located within the refrigerant circuit. The four-way valve 124 can switch the flow path of the refrigerant in the refrigerant circuit between the cooling side and the heating side in response to control by the outdoor unit control unit 180. The outdoor unit control unit 180 drives the valve switching motor 185 with the fifth drive circuit 182, enabling the four-way valve 124 to be switched between the cooling side and the heating side.

[0044] The compressor 125 is located within the refrigerant circuit. The compressor 125 compresses the refrigerant and sends it into the refrigerant circuit in response to control by the outdoor unit control unit 180. The outdoor unit control unit 180 drives the compressor motor 186 with the sixth drive circuit 183, causing the compressor 125 to perform a cyclic operation of refrigerant compression. The outdoor unit control unit 180 can change the rotational speed of the compressor 125 (the number of compression cycles performed per unit time). In other words, the operating frequency of the compressor 125 can be variably controlled.

[0045] During cooling and heating operations, the higher the rotational speed of the compressor 125 (or the higher the operating frequency), the higher the operating load of the air conditioning system 1 tends to be, and the greater the power consumption of the air conditioning system 1 tends to be.

[0046] The air conditioning system 1, using the indoor unit control unit 80 and the outdoor unit control unit 180, switches the four-way valve 124 to the cooling side in cooling operation mode, dehumidification operation mode, etc. The air conditioning system 1, using the indoor unit control unit 80 and the outdoor unit control unit 180, determines the operating frequency of the compressor 125 to a drive frequency based on the temperature difference between the set temperature commanded by the operation terminal 94a, etc., and the indoor temperature. While controlling the compressor 125 to operate at the determined drive frequency, the air conditioning system 1 performs heat absorption processing in the heat exchanger 22, causing the refrigerant to absorb heat from the indoor air, and blows the heated conditioned air into the room. Alternatively, the air conditioning system 1 determines the rotational speed of the compressor 125 to a rotational speed corresponding to the set temperature commanded by the operation terminal 94a, etc. The air conditioning system 1 controls the compressor 125 to operate at a predetermined rotational speed, performs heat absorption processing in the heat exchanger 22, absorbs heat from the indoor air into the refrigerant, and blows the heated conditioned air into the room.

[0047] The air conditioning system 1, using the indoor unit control unit 80 and the outdoor unit control unit 180, switches the four-way valve 124 to the heating side in heating operation mode. The air conditioning system 1, using the indoor unit control unit 80 and the outdoor unit control unit 180, determines the drive frequency of the compressor 125 to a drive frequency based on the temperature difference between the set temperature commanded by the operation terminal 94a, etc., and the room temperature. The air conditioning system 1 controls the compressor 125 to operate at the determined drive frequency, performs heat dissipation processing in the heat exchanger 22, and blows heated conditioned air into the room. Alternatively, the air conditioning system 1 determines the rotational speed of the compressor 125 to a rotational speed corresponding to the set temperature commanded by the operation terminal 94a, etc. The air conditioning system 1 controls the compressor 125 to operate at the determined rotational speed, performs heat dissipation processing in the heat exchanger 22, and blows heated conditioned air into the room.

[0048] The upper and lower air deflectors 25 and the left and right air deflectors 29 each adjust the direction of the conditioned air blown into the room. In this specification, the indoor unit control unit 80 directly controls the direction in which the upper and lower air deflectors 25 and the left and right air deflectors 29 face, but the direction in which the upper and lower air deflectors 25 and the left and right air deflectors 29 face is treated as roughly coinciding with the direction of the air blown out immediately after it leaves the outlet of the indoor unit 10. That is, the upper and lower air deflectors 25 and the left and right air deflectors 29 can adjust the airflow direction by their orientation, and the indoor unit control unit 80 can control the airflow direction by controlling the orientation of the upper and lower air deflectors 25 and the left and right air deflectors 29. Note that multiple upper and lower air deflectors 25 and left and right air deflectors 29 can each have their orientation controlled individually. This allows the indoor unit 10 to blow out air with a unified direction from the entire outlet, or to blow out two or more airflows with different directions from two or more areas of the indoor unit 10's outlet that are partitioned by multiple upper and lower air deflectors 25, left and right air deflectors 29, etc.

[0049] The upper and lower air deflectors 25 can be switched between a closed position and an open position. When the upper and lower air deflectors 25 are switched to the closed position, they close the air outlet. When the upper and lower air deflectors 25 are switched to the open position, they open the air outlet. When the air outlet is open, the upper and lower air deflectors 25 and the left and right air deflectors 29 adjust the direction of the conditioned air blown into the room. The upper and lower air deflectors 25 adjust the direction of the conditioned air in the vertical direction. The left and right air deflectors 29 adjust the direction of the conditioned air in the horizontal direction.

[0050] For example, the vertical air deflectors 25 and the horizontal air deflectors 29 can be configured as shown in Figures 2 to 4. Figure 2 is an illustrative and schematic cross-sectional view showing the schematic configuration of the indoor unit 10 and the state in which the vertical air deflectors 25 and the horizontal air deflectors 29 are switched to the closed position. Figure 3 is an illustrative and schematic cross-sectional view showing the state in which the vertical air deflectors 25 and the horizontal air deflectors 29 are switched to the open position. Figure 4 is a perspective view showing the external configuration and operation of the indoor unit 10, and shows the state in which the vertical air deflectors 25 are in the open position. Hereafter, the longitudinal direction of the indoor unit 10 will be referred to as the X direction, the height direction of the indoor unit 10 as the Z direction, and the direction perpendicular to the X and Z directions as the Y direction.

[0051] As shown in Figures 2 to 4, the indoor unit 10 houses a heat exchanger 22, a fan 23, a filter 24, etc., inside the housing 21 that constitutes the outer shell.

[0052] The housing 21 is formed in a substantially rectangular parallelepiped shape extending in the X direction. However, the housing 21 may be formed in other shapes. The housing 21 is hung, for example, on a wall inside a room. As shown in Figures 2 and 3, the housing 21 has an upper surface 21a and a lower surface 21b. The upper surface 21a is provided at or near the upper end of the housing 21 and faces substantially upward. The lower surface 21b is provided at or near the lower end of the housing 21 and faces substantially downward.

[0053] The housing 21 is provided with an air passage 31, an intake port 32, and an outlet port 33. The air passage 31 is located inside the housing 21. The intake port 32 opens, for example, to the upper surface 21a of the housing 21. The outlet port 33 opens, for example, to the lower surface 21b of the housing 21. The intake port 32 and the outlet port 33 may also open to other parts of the housing 21.

[0054] The indoor unit 10 can pass air through the air passage 31. Air is the flow of gas, such as air. The intake port 32 is provided at one end of the air passage 31 and connects the air passage 31 to the outside of the indoor unit 10. The outlet port 33 is provided at the other end of the air passage 31 and connects the air passage 31 to the outside of the indoor unit 10. In other words, the air passage 31 is provided inside the housing 21 between the intake port 32 and the outlet port 33.

[0055] The heat exchanger 22 is installed in the air passage 31. The heat exchanger 22 exchanges heat with the surrounding gas in the air passage 31. As a result, the heat exchanger 22 cools the air flowing through the air passage 31 during cooling operation and heats the air flowing through the air passage 31 during heating operation.

[0056] The fan 23 is installed in the air passage 31. The fan 23 rotates around a rotation axis Axf extending in the X direction, thereby sending air from the intake port 32 to the outlet port 33 in the air passage 31. As a result, the indoor unit 10 draws indoor air into the air passage 31 from the intake port 32 and blows out the air (wind) from the air passage 31 from the outlet port 33. For this reason, in this specification, the side of the air passage 31 closer to the intake port 32 is referred to as the upstream side, and the side closer to the outlet port 33 is referred to as the downstream side.

[0057] The fan 23 is located downstream of the heat exchanger 22. Therefore, when the fan 23 generates airflow, the air drawn in from the intake port 32 passes through the fins of the heat exchanger 22. As a result, the air flowing through the air passage 31 exchanges heat with the heat exchanger 22.

[0058] The filter 24 is installed at the intake port 32 or near the intake port 32 in the air passage 31. The filter 24 is located upstream of the heat exchanger 22. The filter 24 covers the intake port 32 from inside the housing 21. The filter 24 filters the air drawn in from the intake port 32, for example, and captures dust particles in the air. As described above, by configuring the filter 24 with a HEPA filter or the like, higher quality air purification can be achieved.

[0059] The upper and lower air deflectors 25 may include a plurality of upper and lower air deflectors 25A, 25B. Each of the plurality of upper and lower air deflectors 25A, 25B is a member that adjusts the direction of the conditioned air in the vertical direction, and is also called an upper and lower louver. The upper and lower air deflectors 25A forms a first airflow path C1 for the conditioned air, and the upper and lower air deflectors 25B form a second airflow path C2 for the conditioned air. Each of the plurality of upper and lower air deflectors 25A, 25B has a shaft portion 41 and a plate portion 42.

[0060] The shaft portion 41 is formed in a substantially cylindrical shape extending in the X direction. The shaft portion 41 is supported by the housing 21 so as to be rotatable around a rotation axis Axl extending in the X direction. Each of the multiple upper and lower air deflector plates 25A and 25B has its own rotation axis Axl. The plate portion 42 protrudes from the shaft portion 41 in a direction substantially perpendicular to the rotation axis Axl. The plate portion 42 is formed in a substantially rectangular plate shape extending in the X direction.

[0061] The upper and lower air deflectors 25A are supported by a rotation axis Axl, and the upper and lower air deflector motors 85 are controlled by a second control circuit 82, allowing movement between a closed position Pc1 shown in Figure 2 and an open position Po1 shown in Figure 3. The upper and lower air deflectors 25B are supported by a rotation axis Axl, and the upper and lower air deflector motors 85 are controlled by a second control circuit 82, allowing movement between a closed position Pc1 shown in Figure 2 and an open position Po1 shown in Figure 3.

[0062] As shown in Figure 2, when the upper and lower air deflectors 25A are switched to the closed position Pc1, they block the outlet 33 which is the exit for the first airflow path C1. When the upper and lower air deflectors 25B are switched to the closed position Pc1, they block the outlet 33 which is the exit for the second airflow path C2. The first airflow path C1 and the second airflow path C2 form the outlet 33 of the indoor unit 10.

[0063] As shown in Figures 3 and 4, when the upper and lower air deflectors 25A are switched to the open position Po1, the first airflow channel C1 is opened. When the upper and lower air deflectors 25B are switched to the open position Po1, the second airflow channel C2 is opened.

[0064] The open position Po1 includes various positions in which the upper and lower air deflectors 25A and 25B open a portion of the outlet 33. For example, the open position Po1 includes a position in which the upper and lower air deflectors 25A and 25B are facing approximately horizontally, a position in which the upper and lower air deflectors 25A and 25B are facing downward, and a number of positions in between these two positions, as shown in Figure 3. In other words, the upper and lower air deflectors 25A and 25B are rotatable between a position facing approximately horizontally and a position facing downward.

[0065] The upper and lower air deflectors 25A and 25B, located in the open position Po1, adjust the direction of the air discharged from the outlet 33 in the vertical direction (+Z direction, -Z direction) depending on the orientation of the upper and lower air deflectors 25A and 25B. That is, as shown in Figure 3, when the upper and lower air deflectors 25A and 25B are oriented approximately horizontally, the indoor unit 10 discharges air approximately horizontally. On the other hand, when the upper and lower air deflectors 25A and 25B are oriented downwards, the indoor unit 10 discharges air downwards.

[0066] As shown in Figure 4, the left and right wind vanes 29 are supported by a rotating shaft Ax2 extending in the X direction, and the left and right wind vane motors 86 are controlled by a second control circuit 82, allowing them to move between a rotational position toward the -X side end and a rotational position toward the +X side end.

[0067] The left and right air deflectors 29 may include multiple left and right air deflectors 29-1 to 29-k, 29-(k+1) to 29-2k. Each of the multiple left and right air deflectors 29-1 to 29-k, 29-(k+1) to 29-2k is a component that adjusts the direction of the conditioned airflow in the left and right directions (-X direction, +X direction), and is also called a left and right louver. The direction of the left and right air deflectors 29-1 to 29-k on the -X side and the left and right air deflectors 29-(k+1) to 29-2k on the +X side may be independently controlled by the indoor unit control unit 80.

[0068] The left and right wind vanes 29-1 to 29-k on the -X side may be connected to a common rotation axis Ax2, and the left and right wind vane motors 86 may be controlled by a second control circuit 82, allowing them to move together between the open position at the -X end and the open position at the +X end. The left and right wind vanes 29-(k+1) to 29-2k on the +X side may be connected to a common rotation axis Ax2, and the left and right wind vane motors 86 may be controlled by a second control circuit 82, allowing them to move together between the open position at the -X end and the open position at the +X end.

[0069] The ventilation member 26 is a member having multiple ventilation openings 56 arranged on a plate-shaped plate portion 52. The ventilation member 26 can be switched between an open position Po2 shown in Figure 2 and a closed position Pc2 shown in Figure 3. The ventilation member 26 can be positioned in the closed position Pc2, which covers at least a portion of the outlet 33 (first flow path C1) opened by the upper and lower air deflector plates 25A located in the open position Po1. The ventilation member 26 has an inner surface facing the ventilation passage 31 in the closed position Pc2 and an outer surface facing the outside in the closed position Pc2, and is provided with at least one ventilation opening 56 opening to the inner surface and the outer surface. In the closed position Pc2, the ventilation member 26 can form a first discharge path (first path C1) through which the air supplied by the fan 23 is discharged to the outside via the vent 56, and a second discharge path (second path C2) adjacent to the first discharge path (first path C1) that is discharged to the outside without passing through the vent 56. In other words, when switched to the closed position Pc2, the ventilation member 26 is inserted into a part of the flow path of the conditioned air blown into the room, and changes the opening ratio of a part of the flow path.

[0070] With the ventilation member 26 switched to the open position Po2, its insertion into a portion of the flow path is released (for example, it is retracted from a portion of the flow path), and the opening ratio of the portion of the flow path is returned to its original state.

[0071] In the air conditioning system 1, when the windless mode as an auxiliary operation mode is turned on, the indoor unit control unit 80 switches the ventilation member 26 to the closed position Pc2. With the ventilation member 26 switched to the closed position Pc2, it is selectively inserted into the first flow path C1 and changes the opening ratio of the first flow path C1. On the other hand, the opening ratio of the second flow path C2, which is opened and closed by the upper and lower air deflectors 25B where the ventilation member 26 is not present, is maintained at its original position. When the windless mode as an auxiliary operation mode is deactivated (windless mode off), the indoor unit control unit 80 switches the ventilation member 26 to the open position Po2. With the ventilation member 26 switched to the open position Po2, it is retracted from the first flow path C1 and the opening ratio of the first flow path C1 is returned to its original position.

[0072] As shown in Figure 2, when the ventilation member 26 is switched to the open position Po2, it is housed in a recess 21c of the housing 21 located near the outlet 33. The recess 21c is recessed from the inner surface 21d of the housing 21, which forms part of the ventilation passage 31. When the ventilation member 26 is in the open position Po2, it is housed in the recess 21c, which prevents it from obstructing the airflow through the first flow path C1.

[0073] In the windless mode, as shown in Figure 3, the ventilation member 26 is inserted into the first flow path C1 while switched to the closed position Pc2, thereby changing the opening ratio of the first flow path C1. The opening ratio of the first flow path C1 becomes smaller than before the ventilation member 26 was inserted. The ventilation member 26 is a plate-shaped plate portion 52 with a plurality of ventilation openings 56 arranged on it. The ventilation member 26 is supported by a shaft portion 51 so as to be rotatable about the rotation axis Axc. The switching motor 87 is controlled by the third control circuit 83, and the ventilation member 26 is movable between the closed position Pc2 and the open position Po2. When moved to the closed position Pc2, the air moving through the ventilation passage 31 by the fan 23 passes through the ventilation openings 56.

[0074] On the other hand, the outlet 33 forming the second flow path C2 does not have a ventilation member 26. The opening ratio of the second flow path C2 is maintained as it was originally. In other words, the air released from the second flow path C2 is air that does not pass through the ventilation member 26 (laminar flow). As a result, the air that passes through the ventilation member 26 in the first flow path C1 and the air that passes through the second flow path C2, which does not have a ventilation member 26, are formed adjacent to each other.

[0075] In this case, as the opening ratio of the first flow path C1 decreases, the velocity of the air passing through the ventilation member 26 increases, and it transitions to turbulent flow. The increased velocity of the air then draws in slower-velocity air (laminar flow) that does not pass through the ventilation member 26. Furthermore, the turbulent air diffuses and strikes the laminar flow adjacent to the turbulent air. In this way, air with different velocities and states (laminar or turbulent) collide with each other as they flow side by side. That is, the air that does not pass through the ventilation member 26 (ventilation opening 56) and the air that does pass through the ventilation member 26 (ventilation opening 56) interfere with each other. As a result, the clusters of laminar and turbulent flow are broken up, and the turbulent air is carried into the laminar flow. Air with different velocities and states undergo various interactions, generating a mixed air (turbulent flow) that diffuses over a wide area. As a result, the turbulent air discharged from the indoor unit 10 is closer to natural wind (so-called windless wind) than the wind immediately after it is discharged from the outlet 33. In this case, the ventilation member 26 only needs to be formed in either the first flow path C1 or the second flow path C2, which helps to suppress an increase in the number of parts, an increase in the complexity of the indoor unit 10's configuration, and a rise in cost. Furthermore, the ventilation member 26 has a simple structure consisting only of a ventilation opening 56, which helps to suppress an increase in cost and a decrease in the strength of the ventilation member 26.

[0076] Returning to Figure 1, radar 2 can detect the position, speed, angle, and shape (height from the floor, etc.) of a detection target (e.g., user CR) in the room. Radar 2 is a Doppler radar such as an ultrasonic radar, millimeter-wave radar, microwave radar, or lidar. Radar 2 has a transmitter 2a, a receiver 2b, and a signal processing unit 2c. Radar 2 generates radio waves such as millimeter waves and microwaves, sound waves, and light in the signal processing unit 2c and transmits them to the room area from the transmitter 2a. The receiver 2b receives the reflected waves reflected by detection targets (user CR) etc. that may be present in the room area and passes them to the signal processing unit 2c. Radar 2 is installed at any position on the front of the housing 21 of the indoor unit 10, but it is desirable to install it at a position that makes it easy to detect the position of detection targets (user CR) etc. in the room area. Radar 2 may be embedded in the housing 21 near the center in the X direction on the +Y side, as shown by the dotted line in Figures 2 to 4. Furthermore, it is desirable that the transmitting unit 2a and the receiving unit 2b be exposed from the surface of the housing 21, as shown in Figure 4.

[0077] Radar 2 can detect the position of the biological CR from the phase difference and direction of the transmitted and received waves using the signal processing unit 2c.

[0078] Radar 2 detects the location of the target space and the biological CR within the target space in accordance with the control of the indoor unit control unit 80. Radar 2 periodically or continuously transmits and receives radio waves to the biological CR to detect its location and periodically or continuously supplies the detection results to the indoor unit control unit 80.

[0079] In this case, if the signal processing function in the signal processing unit 2c is implemented as a hardware signal processing circuit, signal processing can be performed at a higher speed compared to when the signal processing function is implemented in software. High-speed signal processing by the signal processing circuit allows for high-speed detection of the biological CR's position based on the phase difference between the transmitted and received waves. This enables near real-time detection of the biological CR's current position, making it easier to perform control that tracks the biological CR's current position.

[0080] The transceiver 94 shown in Figure 1 receives commands from the operation terminal 94a, etc. The transceiver 94 supplies the received commands to the indoor unit control unit 80. The indoor unit control unit 80 may forward the commands to the outdoor unit control unit 180. Figure 5 is a perspective view showing the external configuration of the operation terminal 94a, illustrating a configuration when the operation terminal 94a is a remote controller.

[0081] The operating terminal 94a has a shape and dimensions suitable for operation by a bioCR and has a substantially rectangular parallelepiped appearance. The operating terminal 94a has a plurality of buttons and a display unit 949 on its operating surface. The plurality of buttons include, for example, a biosensor button 941 (radar button), a cooling button 942, a heating button 943, an air purification button 944, a temperature setting button 945, a dehumidification button 946, a windless button 947, a stop button 948, a weak cooling button 9410, a weak heating button 9411, and an airflow setting button 9412. The display unit 949 may be a display or an indicator. The display includes a liquid crystal display or an organic EL display. The indicator includes a 7-segment LED display.

[0082] The control terminal 94a detects when the following buttons are pressed: biosensor button 941, cooling button 942, heating button 943, air purification button 944, dehumidification button 946, no-draft button 947, stop button 948, weak cooling button 9410 (weak operation mode button), and weak heating button 9411 (weak operation mode button). The control terminal 94a also detects when the △ or ▽ button is pressed for the temperature setting button 945. The control terminal 94a also detects when the △ or ▽ button is pressed for the airflow setting button 9412. When the control terminal 94a detects a press, it displays information about the command corresponding to the pressed button on the display unit 949 and transmits a signal (for example, an infrared signal or a wireless signal) indicating the command corresponding to the pressed button from its end.

[0083] The operating terminal 94a may be capable of receiving commands to turn the weak cooling mode (weak operation mode) on or off via the weak cooling button 9410.

[0084] When the control terminal 94a detects the pressing of a button that commands the weak cooling mode to be turned on (for example, pressing the weak cooling button 9410), it transmits a command to turn on the weak cooling mode to the indoor unit 10. When the transmitting / receiving device 94 receives the command to turn on the weak cooling mode, it supplies the command to the indoor unit control unit 80. The indoor unit control unit 80 forwards the command to turn on the weak cooling mode to the outdoor unit control unit 180. It then executes constant-speed operation control of the compressor 125 and starts operation in which the heat exchanger 22 functions as an evaporator and the heat exchanger 122 functions as a condenser. In other words, weak cooling operation in weak operation mode can be achieved with simple operation (for example, the operation of a single button).

[0085] Furthermore, when the operating terminal 94a receives a command to turn on the weak cooling mode, it may display information related to the weak cooling mode on the display unit 949. The information related to the weak cooling mode may be, for example, text information indicating the weak cooling mode, such as "weak cooling," or it may be a display object such as a graphic or symbol representing "weak cooling."

[0086] Furthermore, the reason the indoor unit control unit 80 transmits the command to turn on the weak cooling mode to the outdoor unit control unit 180 is so that the indoor unit control unit 80 and the outdoor unit control unit 180 can cooperate to control the operation of the weak cooling mode. However, the indoor unit control unit 80 may be the primary unit to perform the air conditioning processing. In that case, the process by which the indoor unit control unit 80 transmits the command to turn on the weak cooling mode to the outdoor unit control unit 180 may be omitted. The outdoor unit 120 may be configured without the outdoor unit control unit 180. Alternatively, the outdoor unit control unit 180 may be the primary unit to perform the air conditioning processing. In that case, the outdoor unit 120 may be configured without the indoor unit control unit 80. The transmitting and receiving device 94 may directly transmit the command to turn on the weak cooling mode to the outdoor unit control unit 180.

[0087] When the control terminal 94a detects the pressing of a button that commands the weak cooling mode to be turned off (for example, pressing the weak cooling button 9410 again), it transmits a command to turn off the weak cooling mode to the indoor unit 10. When the transmitting / receiving device 94 receives the command to turn off the weak cooling mode, it supplies the command to the indoor unit control unit 80. The indoor unit control unit 80 forwards the command to turn off the weak cooling mode to the outdoor unit control unit 180. As a result, the weak cooling mode (weak operation mode) is turned off, and the system switches to normal cooling operation (normal operation mode).

[0088] The operating terminal 94a may be capable of receiving commands to turn the low heating mode on or off via the low heating button 9411.

[0089] When the control terminal 94a detects the pressing of a button that commands the low-heating mode to be turned on (for example, pressing the low-heating button 9411), it transmits a command to turn on the low-heating mode to the indoor unit 10. When the transmitting / receiving device 94 receives the command to turn on the low-heating mode, it supplies the command to the indoor unit control unit 80. The indoor unit control unit 80 forwards the command to turn on the low-heating mode to the outdoor unit control unit 180. It then executes constant-speed operation control of the compressor 125 and starts operation in which the heat exchanger 22 functions as a condenser and the heat exchanger 122 functions as an evaporator. In other words, low-heating operation in low-power mode can be achieved with simple operation (for example, the operation of a single button).

[0090] Furthermore, when the operating terminal 94a receives a command to turn on the low heating mode, it may display information related to the low heating mode on the display unit 949. The information related to the low heating mode may be, for example, text information indicating the low heating mode, such as "low heating," or it may be a display object such as a graphic or symbol representing "low heating."

[0091] Furthermore, the reason the indoor unit control unit 80 transmits the command to turn on the low heating mode to the outdoor unit control unit 180 is so that the indoor unit control unit 80 and the outdoor unit control unit 180 can cooperate to control the operation of the low heating mode. However, the indoor unit control unit 80 may be the primary unit to perform the air conditioning processing. In that case, the process by which the indoor unit control unit 80 transmits the command to turn on the low heating mode to the outdoor unit control unit 180 may be omitted. The outdoor unit 120 may be configured without the outdoor unit control unit 180. Alternatively, the outdoor unit control unit 180 may be the primary unit to perform the air conditioning processing. In that case, the outdoor unit 120 may be configured without the indoor unit control unit 80. The transmitting and receiving device 94 may directly transmit the command to turn on the low heating mode to the outdoor unit control unit 180.

[0092] When the control terminal 94a detects the pressing of a button that commands the low-heat mode off (for example, pressing the low-heat button 9411 again), it transmits a command to the indoor unit 10 to turn off the low-heat mode. When the transmitting / receiving device 94 receives the command to turn off the low-heat mode, it supplies the command to the indoor unit control unit 80. The indoor unit control unit 80 forwards the command to turn off the low-heat mode to the outdoor unit control unit 180. As a result, the low-heat mode (low operation mode) is turned off, and the system switches to the normal heating operation mode (normal operation mode).

[0093] Furthermore, the control unit of the air conditioner 1 (indoor unit control unit 80, outdoor unit control unit 180) may be configured to automatically cancel the low-power mode setting if the air conditioner 1 is stopped by pressing the stop button 948 after setting the low-power mode (execution of low-power mode by operating the low-power cooling button 9410, or execution of low-power mode by operating the low-power heating button 9411). In other words, by automatically canceling the low-power mode, it is possible to prevent the low-power mode from being unintentionally executed the next time the air conditioner 1 is used.

[0094] The operating terminal 94a may also be capable of receiving commands for a set temperature via the temperature setting button 945.

[0095] When the operation terminal 94a detects that the △ button of the temperature setting button 945 is pressed, it increases the set temperature value from the current value, displays the increased set temperature value on the display unit 949, and transmits a command for the increased set temperature to the indoor unit 10. When the operation terminal 94a detects that the ▽ button of the temperature setting button 945 is pressed, it decreases the set temperature value from the current value, displays the decreased set temperature value on the display unit 949, and transmits a command for the decreased set temperature to the indoor unit 10. When the transmitting / receiving device 94 receives a command for the increased or decreased set temperature, it supplies the command to the indoor unit control unit 80. The indoor unit control unit 80 may also forward the set temperature command to the outdoor unit control unit 180.

[0096] The operating terminal 94a may also be capable of receiving commands for a set airflow rate via the airflow setting button 9412.

[0097] When the control terminal 94a detects that the △ button of the airflow setting button 9412 is pressed, it increases the size of the set airflow from the current size, displays the changed set airflow value on the display unit 949, and transmits a command for the changed set airflow to the indoor unit 10. When the control terminal 94a detects that the ▽ button of the airflow setting button 9412 is pressed, it decreases the size of the set airflow from the current size, displays the changed set airflow value on the display unit 949, and transmits a command for the changed set airflow to the indoor unit 10. When the transceiver 94 receives a command for the set airflow, it supplies the command to the indoor unit control unit 80. The indoor unit control unit 80 forwards the command for the set airflow to the outdoor unit control unit 180.

[0098] One of the characteristic controls in the air conditioning system 1 configured in this way, the "low-power operation mode," will be explained using Figures 6 to 11.

[0099] As mentioned above, when performing cooling or heating operations, the higher the rotational speed of the compressor 125 (or the higher the operating frequency), the higher the operating load of the air conditioner 1, and the greater the power consumption of the air conditioner 1 tends to be. In addition, in the case of a typical air conditioner, when performing cooling or heating operations, for example, the compressor 125 is driven at a high load (e.g., the highest operating frequency) to quickly approach the set temperature set on the operation terminal 94a during control execution, and then, once the room temperature reaches the set temperature, the compressor 125 is controlled ON / OFF to maintain the room temperature relative to the set temperature. When the compressor 125 is repeatedly turned ON / OFF in this way to adjust the temperature, power consumption also tends to be high.

[0100] For example, Figure 6 is an illustrative diagram illustrating the difference in room temperature change during normal operation control (normal operation mode) and constant-speed operation control (constant-speed operation mode) in the cooling operation of the air conditioner 1. Here, normal operation control is an operation control that controls the operating frequency of the compressor 125 according to the set temperature set on the indoor unit 10 and the room temperature in the room where the indoor unit 10 is installed (for example, according to the difference between the set temperature and the room temperature) to blow out conditioned air from the indoor unit. Constant-speed operation control is an operation control that controls the compressor 125 at a constant constant-speed operating frequency lower than the maximum operating frequency possible in normal operation control, regardless of the room temperature, to blow out conditioned air from the indoor unit 10. Note that the maximum operating frequency of the compressor 125 and the minimum operating frequency, which will be described later, differ depending on the air conditioning capacity required of the air conditioner 1 (indoor unit 10). The air conditioning capacity differs depending on the size of the room in which the indoor unit 10 is installed (for example, the number of tatami mats). In the case of a household air conditioning system 1, the maximum operating frequency of the compressor 125 is, for example, 60-90 Hz, and the minimum operating frequency is, for example, 10-15 Hz.

[0101] In Figure 6, the temperature change during normal operation control is shown on temperature line TL1, and the temperature change during constant-speed operation control is shown on temperature line TL. In normal operation control, temperature line TL1 quickly reaches the set temperature T after cooling starts, but when it reaches the thermo-off temperature T0 (the temperature at which the compressor 125 is temporarily stopped) relative to the set temperature T, the compressor 125 is turned OFF. In other words, the cooling capacity temporarily decreases and the room temperature begins to rise. Then, when the room temperature becomes higher than a predetermined value relative to the set temperature T, the compressor 125 is turned ON again, the cooling capacity increases, and the room temperature can be lowered. By repeating this operation, the room temperature is maintained near the set temperature T.

[0102] On the other hand, in constant-speed operation control, the temperature line TL controls the compressor 125 at a constant constant-speed operating frequency lower than the highest operating frequency possible in normal operation control. As a result, although the room temperature decreases compared to before the start of cooling operation, the rate of decrease is slower than in normal operation control. However, the room temperature can be lowered to the level at which the user would have expected if they had tried to use the air conditioning, thus providing a certain level of satisfaction to the user.

[0103] Figure 7 is an illustrative diagram illustrating the difference between the operating capacity line WL1 during normal operation control (normal operation mode) and the operating capacity line WL during constant-speed operation control (constant-speed operation mode) in the air conditioning unit 1 during cooling operation. As shown in Figure 7, the operating capacity line WL1 during normal operation control shows large fluctuations in power consumption due to the ON / OFF control of the compressor 125. As a result, as shown by the temperature line TL1 in Figure 6, the room temperature quickly reaches near the set temperature T and quickly maintains that temperature, but this can lead to higher electricity costs and hinder energy saving.

[0104] On the other hand, in the case of constant-speed operation control, the constant-speed operation frequency is set to a frequency lower than the midpoint between the maximum operating frequency and the minimum operating frequency of the compressor 125. If the maximum operating frequency of the compressor 125 is, for example, 60Hz and the minimum operating frequency is, for example, 10Hz, the midpoint is 35Hz. The operating capacity line WL in Figure 7 represents the case when the compressor 125 is operated at, for example, the minimum capacity W0 (the lowest frequency drive at which cooling operation is possible = 10Hz), which is lower than the midpoint. In this case, as shown by the temperature line TL in Figure 6, although the decrease in room temperature is slow, the increase in electricity costs can be suppressed.

[0105] In other words, with constant-speed operation control, the air conditioner 1 (compressor 125) operates at, for example, its minimum capacity, enabling energy-saving operation while reducing electricity costs. Furthermore, because constant-speed operation control maintains a nearly constant power output, it becomes easier to estimate the electricity cost. For example, predicting the electricity cost when constant-speed operation control is maintained becomes easier, contributing to easier electricity cost management. Additionally, because the power output is lower than during normal cooling operation, thermostat off-times are less likely. This means that the compressor 125 is less likely to switch on and off, further contributing to suppressing increases in power consumption. Moreover, with constant-speed operation control, it is easier to accommodate requests for gentle cooling with weak airflow or to avoid rapid temperature changes, allowing for the proposal (provision) of new energy-saving operation methods tailored to different usage scenarios. Similar effects can be obtained when applying constant-speed operation control (weak operation mode) to heating operation.

[0106] As described above, the air conditioning system 1 of this embodiment is capable of performing normal operation control and constant speed operation control through the cooperation of the indoor unit control unit 80 and the outdoor unit control unit 180. Furthermore, when the user selects the low-speed operation mode, the system can be controlled to maintain constant speed operation control for a predetermined period after the start of constant speed operation control. In other words, as described above, the low-speed operation mode can be used when you want to cool (warm) gently with a weak cool air (weak warm air), when you want to avoid rapid temperature changes, when you want to save electricity at the same time, or when you want to prioritize saving electricity. To use the low-speed operation mode, you will need to operate the weak cooling button 9410 or the weak heating button 9411 on the operation terminal 94a shown in Figure 5. Note that although the weak cooling button 9410 and the weak heating button 9411 are provided separately on the operation terminal 94a, they may be combined into a single low-speed operation button. In this case, the same operation can be achieved by combining the low-speed operation button with the cooling button 942 or the heating button 943.

[0107] By the way, the constant-speed operation control described above operates with the compressor 125's capacity reduced, so the room temperature may change depending on the conditions inside the room where the indoor unit 10 is installed, such as changes in the outside temperature, the amount of sunlight entering through the window, and changes in the number of people (users) in the room or their activity levels. For example, when constant-speed operation control is applied during cooling operation, the room temperature may rise contrary to the cooling capacity of the constant-speed operation control due to rising outside temperatures, increased sunlight, or an increase in the number of people. In such cases, the outdoor unit control unit 180 (indoor unit control unit 80), when the low-speed operation mode is selected, the indoor heat exchanger functions as an evaporator, and constant-speed operation control is being executed, may switch the control state to normal operation control when the room temperature exceeds the first threshold temperature TS1 (corresponding to the upper limit switching threshold temperature in this invention), as shown in Figure 8. In other words, if the room temperature rises too high (exceeds the first threshold temperature TS1), for example, to avoid user discomfort, the control is switched to normal operation control to lower the room temperature.

[0108] Subsequently, the outdoor unit control unit 180 (indoor unit control unit 80) switches to normal operation control when the room temperature falls below the second threshold temperature TS2, that is, when the low-speed operation mode is selected, the heat exchanger 22 (indoor heat exchanger) functions as an evaporator, and normal operation control is executed, and the room temperature falls below the second threshold temperature TS2 as a result of this normal operation control. For example, when a comfortable room temperature is reached, the control switches to the control desired by the user. In other words, it automatically switches to a control that responds to requests such as wanting to cool gently with a weak cool breeze, wanting to avoid rapid temperature changes, wanting to save energy, or wanting to prioritize energy saving. As shown by the temperature line TC in Figure 8, even if the system switches from constant-speed operation control (low-speed operation mode) to normal operation control and cools down to the second threshold temperature TS2, the compressor 125 does not stop, but switches back to constant-speed operation control, thus avoiding the increase in power consumption caused by ON / OFF operation. In other words, it contributes to energy saving.

[0109] The first threshold temperature TS1 may be a fixed value, such as 32°C, and the second threshold temperature TS2 may be a fixed value, such as 28°C. Alternatively, the user may be able to set these values ​​as appropriate using, for example, an operation terminal 94a. In Figure 8, the set temperature T (for example, 26°C) during cooling is shown for comparison of the second threshold temperature TS2. However, in the low-power operation mode (low-cooling mode), the set temperature T is not set, and the compressor 125 is operated at a low load to achieve gentle low-power cooling and energy saving.

[0110] Even when cooling is performed gently in low-power mode (low-cooling mode), the room temperature may drop too low depending on the indoor conditions. For example, this can occur when the outside temperature drops at night, when sunlight is weaker, or when there are fewer people (users) in the room or their activity decreases, reducing the factors that cause the room temperature to rise. In such cases, the outdoor unit control unit 180 (indoor unit control unit 80) may, when low-power mode is selected, the indoor heat exchanger functions as an evaporator, and constant-speed operation control of the compressor 125 is performed, stop the operation of the compressor 125 when the room temperature falls below the third threshold temperature TS3 (corresponding to the lower limit stop threshold temperature in this invention), as shown in Figure 9. In other words, if the room temperature drops too low, for example, to suppress discomfort caused by excessive cooling, the compressor 125 is stopped. In this case, when using cooling operation, it is presumed that the outside temperature is relatively high. Therefore, the natural rise in room temperature suppresses the room temperature from dropping too low.

[0111] For example, when the low-power mode is selected, after the compressor 125 stops, the outdoor unit control unit 180 (indoor unit control unit 80) may switch the control state to constant-speed operation control if the room temperature rises to or above the fourth threshold temperature TS4 due to natural temperature increase. In other words, the control automatically switches to a mode that meets the needs of those who want to cool gently with a weak breeze, perform cooling while avoiding rapid temperature changes, save energy, or prioritize energy saving. As shown by the temperature line TC in Figure 9, in the low-power mode (weak cooling mode), the constant-speed operation control is turned ON / OFF, but since the constant-speed operation control itself is operated at, for example, the lowest capacity, the increase in power consumption caused by the ON / OFF operation can be suppressed.

[0112] The third threshold temperature TS3 may be a fixed value, for example, 25°C, and the fourth threshold temperature TS4 may be a fixed value, for example, 28°C, or the user may be able to set it as appropriate using, for example, an operation terminal 94a.

[0113] When operating in low-power mode (low-cooling mode), if the room temperature falls below the third threshold temperature TS3 and the compressor 125 stops operating, the fan 23 of the indoor unit 10 may be stopped, or the fan 23 may continue to operate to provide only airflow. By continuing to provide airflow with the fan 23, indoor air can be circulated, contributing to the maintenance of the indoor environment.

[0114] Next, we will explain the low-power mode during heating operation using Figures 10 and 11.

[0115] Even when the low-power mode is applied during heating operation, the constant-speed operation control operates with the compressor 125's capacity suppressed, just as during cooling operation. Therefore, the room temperature may change depending on the conditions in the room where the indoor unit 10 is installed, such as changes in outside temperature, the amount of sunlight entering through the window, and changes in the number of people (users) in the room or their activity levels. For example, the room temperature may drop contrary to the heating capacity of the constant-speed operation control due to a decrease in outside temperature, a decrease in sunlight, or a decrease in the number of people. In such cases, the outdoor unit control unit 180 (indoor unit control unit 80), when the low-power mode is selected, the indoor heat exchanger functions as a condenser, and constant-speed operation control is being executed, may switch the control state to normal operation control when the room temperature falls below the fifth threshold temperature TS5 (corresponding to the lower limit switching threshold temperature in this invention), as shown in Figure 10. In other words, if the room temperature drops too low (falls below the fifth threshold temperature TS5), for example, to avoid user discomfort, the control is switched to normal operation control to raise the room temperature.

[0116] Subsequently, the outdoor unit control unit 180 (indoor unit control unit 80) switches to the control system that meets the user's requirements when the room temperature reaches or exceeds the sixth threshold temperature TS6 through normal operation control. This occurs when the low-speed operation mode is selected, the heat exchanger 22 (indoor heat exchanger) functions as a condenser, and normal operation control is executed, and the room temperature reaches or exceeds the sixth threshold temperature TS6 through this normal operation control. For example, when the room temperature reaches a level where extreme cold is not felt, the system switches to the control system that the user desires. In other words, it automatically switches to a control system that meets the user's requirements, such as wanting to be gently warmed with a weak warm airflow, wanting to avoid rapid temperature changes, wanting to save energy, or prioritizing energy saving. As shown by the temperature line TC in Figure 10, even if the system switches from constant-speed operation control (low-speed operation mode) to normal operation control and heats up to the sixth threshold temperature TS6, the compressor 125 does not stop and switches back to constant-speed operation control, thus avoiding the increase in power consumption caused by ON / OFF operation. In other words, it contributes to energy saving.

[0117] The fifth threshold temperature TS5 may be a fixed value, for example, 20°C, and the sixth threshold temperature TS6 may be a fixed value, for example, 25°C. Alternatively, the user may be able to set these values ​​as appropriate using, for example, an operation terminal 94a. In Figure 10, the set temperature T (for example, 27°C) during heating is shown for comparison with the sixth threshold temperature TS6. However, in the low-power operation mode (low-power heating mode), the set temperature T is not set, and the compressor 125 is operated at a load lower than the maximum operating frequency to achieve gentle low-power heating and energy saving.

[0118] Even when heating is performed gently in low-power mode (low-heating mode), the room temperature may rise too high depending on the indoor conditions. For example, this can occur when the outside temperature rises during the day, when sunlight becomes stronger, or when there is an increase in the number of people (users) or increased activity inside the room, thus increasing the factors that cause the room temperature to rise. In such cases, the outdoor unit control unit 180 (indoor unit control unit 80) may, when low-power mode is selected, the indoor heat exchanger functions as a condenser, and constant-speed operation control of the compressor 125 is being performed, stop the operation of the compressor 125 when the room temperature exceeds the seventh threshold temperature TS7 (corresponding to the upper limit stop threshold temperature in this invention), as shown in Figure 11. In other words, if the room temperature rises too high, for example, to suppress discomfort caused by overheating, the compressor 125 is stopped. In this case, when using heating operation, it is presumed that the outside temperature is relatively low. Therefore, the room temperature will rise too high due to natural temperature decrease.

[0119] For example, when the low-power mode is selected, after the compressor 125 stops, the outdoor unit control unit 180 (indoor unit control unit 80) may switch the control state to constant-speed operation control if the room temperature falls below the eighth threshold temperature TS8 due to natural temperature decrease. In other words, the control automatically switches to a mode that meets the needs of those who want to warm gently with low-power heating, who want to perform heating that avoids rapid temperature changes, who want to save energy at the same time, or who want to prioritize energy saving. As shown by the temperature line TC in Figure 11, in the low-power mode (low-power heating mode), the constant-speed operation control is turned ON / OFF, but since the constant-speed operation control itself is operated at, for example, the lowest capacity, the increase in power consumption caused by the ON / OFF operation can be suppressed.

[0120] The seventh threshold temperature TS7 may be a fixed value, such as 27°C, and the eighth threshold temperature TS8 may be a fixed value, such as 20°C, or the user may be able to set it as appropriate using, for example, an operating terminal 94a.

[0121] When operating in low-power mode (low-power heating mode), if the room temperature rises to or above the seventh threshold temperature TS7 and the compressor 125 stops operating, the fan 23 of the indoor unit 10 may be stopped, or the fan 23 may continue to operate to provide only airflow. By continuing to provide airflow with the fan 23, indoor air can be circulated, contributing to the maintenance of the indoor environment.

[0122] In this way, by operating the air conditioner 1 in low-power mode, it is easy to perform operational controls such as avoiding rapid temperature changes during cooling and heating operations, obtaining appropriate cooling and heating effects, saving electricity, or prioritizing energy saving.

[0123] Furthermore, the low-speed operation mode maintains constant-speed operation control for a predetermined period, for example, 30 minutes, from the start of the low-speed operation mode (constant-speed operation control). As a result, even if the threshold for transitioning to normal operation control (the first threshold temperature TS1 or the fifth threshold temperature TS5) is exceeded, if there is a temperature change due to constant-speed operation control (such as a temperature drop during cooling or a temperature rise during heating), it is possible to prevent the system from immediately switching to normal operation control. In other words, the low-speed operation mode can be used at the user's discretion. The predetermined period (for example, 30 minutes) may be a fixed value, or it may be set as appropriate by the user.

[0124] Furthermore, when selecting the low-speed operation mode, if the system returns from normal operation control to constant-speed operation control, or from a stopped state to constant-speed operation control, the operating frequency of the compressor 125 in constant-speed operation control may be reviewed to operate the compressor 125 in a manner suitable for the room temperature. As a result, energy savings through low-load constant-speed operation control and heating and cooling operation that provides a reasonable level of satisfaction can be achieved.

[0125] During the execution of the constant-speed operation control described above, the airflow from fan 23 (indoor ventilation fan) may be variably controlled. For example, during cooling operation (low cooling), increasing the airflow from fan 23 can lower the perceived temperature, further improving comfort even during constant-speed operation control. Similarly, during heating operation (low heating), decreasing the airflow from fan 23 can suppress the decrease in perceived temperature, further improving comfort even during constant-speed operation control. At the start of constant-speed operation control, the airflow from fan 23 may be set to the minimum airflow as the default value. After that, the user may be able to freely change the airflow by operating the operation terminal 94a or the like.

[0126] Furthermore, the outdoor unit control unit 180 (indoor unit control unit 80) may also be configured to cancel the low-power operation mode setting if the air conditioner 1 is stopped by operating the stop button 948 or similar after the low-power operation mode has been set by operating the low-power cooling button 9410 or low-power heating button 9411 on the operation terminal 94a or similar. This automatic cancellation prevents, for example, the unintentional activation of the low-power operation mode the next time the air conditioner 1 is used. In other words, it prevents the air conditioner 1 from operating with reduced cooling or heating capacity, which could cause discomfort to the user. To put it another way, the low-power operation mode, which reduces air conditioning capacity, can be configured to operate only when intended by the user.

[0127] <Summary> The air conditioning system 1 according to the embodiment described above comprises an indoor unit 10 including an indoor heat exchanger (heat exchanger 22) and an indoor blower fan (fan 23), an outdoor unit 120 including an outdoor heat exchanger (heat exchanger 122) and an outdoor blower fan (fan 123), a refrigerant piping RL connecting the indoor heat exchanger (heat exchanger 22) and the indoor heat exchanger (heat exchanger 122) through which the refrigerant flows, a compressor 125 provided in the outdoor unit 120 that compresses the refrigerant with variable controllable operating frequency, an expansion valve provided in the outdoor unit 120, and a control unit (indoor unit control unit 80, outdoor unit control unit 180) that performs air conditioning operation based on the refrigerant flow pattern, and the control unit ( The air conditioning system is capable of performing two modes: a normal operation mode in which the indoor unit control unit 80 and the outdoor unit control unit 180 control the operating frequency of the compressor 125 according to the set temperature set in the indoor unit 10 and the room temperature in which the indoor unit 10 is installed, thereby performing normal operation control to blow out conditioned air from the indoor unit 10; and a low-speed operation mode in which the compressor 125 is controlled at a constant constant-speed operating frequency lower than the highest operating frequency possible in normal operation control, regardless of the room temperature, thereby performing constant-speed operation control to blow out conditioned air from the indoor unit 10. If the low-speed operation mode is selected by the user, the constant-speed operation control is maintained for a predetermined period of time from the start of the constant-speed operation control.

[0128] This configuration makes it possible to provide an air conditioning system 1 that can suppress an increase in power consumption while maintaining a certain level of comfort.

[0129] Furthermore, the control units of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, set the constant speed operation frequency to a frequency lower than the midpoint between the maximum operation frequency and the minimum operation frequency of the compressor 125 when performing constant speed operation control.

[0130] This configuration allows for energy conservation, for example, by continuing low-power operation with reduced output power.

[0131] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, switch the control state to normal operation control when the room temperature rises above a first threshold temperature TS1, while the low-speed operation mode is selected, the indoor heat exchanger (heat exchanger 22) is functioning as an evaporator, and constant-speed operation control is being performed.

[0132] With this configuration, for example, excessive temperature increases during cooling operation in low power mode can be suppressed, contributing to improved comfort.

[0133] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, be configured to switch the control state to constant speed operation control when the room temperature falls below the second threshold temperature TS2 due to the normal operation control when the low-speed operation mode is selected and the indoor heat exchanger (heat exchanger 22) functions as an evaporator.

[0134] This configuration, for example, suppresses excessive execution of normal operation control during cooling operation in low-power mode, thereby contributing to energy conservation.

[0135] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, stop the operation of the compressor 125 when the room temperature falls below the third threshold temperature TS3, if the low-speed operation mode is selected, the indoor heat exchanger (heat exchanger 22) functions as an evaporator, and constant-speed operation control is being performed.

[0136] This configuration, for example, prevents excessive cooling from being used, thus contributing to energy conservation.

[0137] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, switch the control state to constant speed operation control when the room temperature rises to or above the fourth threshold temperature TS4 after the compressor 125 has stopped, if the low-speed operation mode is selected and the compressor 125 has stopped.

[0138] With this configuration, for example, when using the cooling function in low-power mode, it becomes possible to prevent the room temperature from rising too high, contributing to improved comfort.

[0139] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, switch the control state to normal operation control when the room temperature falls below the fifth threshold temperature TS5, while the low-speed operation mode is selected and the indoor heat exchanger (heat exchanger 22) is functioning as a condenser and constant-speed operation control is being performed.

[0140] With this configuration, for example, excessive drops in room temperature during heating operation in low power mode can be suppressed, contributing to improved comfort.

[0141] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, be configured to switch the control state to constant speed operation control when the room temperature rises to or above the sixth threshold temperature TS6 by the normal operation control when the low-speed operation mode is selected and the indoor heat exchanger (heat exchanger 22) functions as a condenser.

[0142] This configuration, for example, suppresses excessive execution of normal operation control during heating operation in low-power mode, thereby contributing to energy conservation.

[0143] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, stop the operation of the compressor 125 when the room temperature reaches or exceeds the seventh threshold temperature TS7, if the low-speed operation mode is selected, the indoor heat exchanger (heat exchanger 22) functions as a condenser, and constant-speed operation control is being performed.

[0144] This configuration, for example, prevents excessive heating from being used, thus contributing to energy conservation.

[0145] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, switch the control state to constant speed operation control when the room temperature falls below the eighth threshold temperature TS8 after the compressor 125 has stopped, if the low-speed operation mode is selected and the compressor 125 has stopped.

[0146] With this configuration, for example, when using the heating function in low power mode, it becomes possible to prevent the room temperature from dropping too low, which contributes to improved comfort.

[0147] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may be configured to allow variable control of the airflow from the indoor blower fan (fan 23) while constant speed operation control is being performed.

[0148] With this configuration, for example, during cooling operation (low cooling), increasing the airflow from fan 23 makes it possible to lower the perceived temperature, contributing to improved comfort. Similarly, during heating operation (low heating), decreasing the airflow from fan 23 makes it possible to suppress the decrease in perceived temperature, contributing to improved comfort.

[0149] Furthermore, the control units of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, cancel the low-speed operation mode setting if the air conditioning system is stopped after setting the low-speed operation mode.

[0150] With this configuration, for example, by automatically canceling the low-power mode, it is possible to prevent the low-power mode from being unintentionally activated the next time the air conditioner 1 is used.

[0151] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, when it receives a signal indicating weak cooling among the weak operation modes, execute constant speed operation control and start operation in which the indoor heat exchanger (heat exchanger 22) functions as an evaporator and the outdoor heat exchanger (heat exchanger 122) functions as a condenser.

[0152] With this configuration, for example, it is possible to achieve weak cooling operation in weak mode with simple operation.

[0153] Furthermore, the control unit of the air conditioning system 1 (indoor unit control unit 80, outdoor unit control unit 180) may, for example, when it receives a signal indicating weak heating in the weak operation mode, execute constant speed operation control and start operation in which the indoor heat exchanger (heat exchanger 22) functions as a condenser and the outdoor heat exchanger (heat exchanger 122) functions as an evaporator.

[0154] With this configuration, for example, low-power heating operation in low-power mode can be achieved with simple operation.

[0155] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. <Additional notes> [Appendix 1] An indoor unit including an indoor heat exchanger and an indoor blower fan, An outdoor unit including an outdoor heat exchanger and an outdoor blower fan, The indoor heat exchanger and the outdoor heat exchanger are connected, and a refrigerant pipe through which the refrigerant flows is provided. A compressor is provided in the outdoor unit, capable of variably controlling the operating frequency and for compressing the refrigerant, An expansion valve provided in the outdoor unit, A control unit that performs air conditioning operation based on the refrigerant flow pattern, Equipped with, The control unit, A normal operation mode is performed to control the operating frequency of the compressor according to the set temperature set in the indoor unit and the room temperature in which the indoor unit is installed, thereby blowing out conditioned air from the indoor unit. A low-speed operation mode is possible, in which the operating frequency of the compressor is controlled to be constant at an operating frequency lower than the maximum operating frequency in the normal operation control, thereby performing constant-speed operation control to blow out conditioned air from the indoor unit. The user can set the low-power mode, and if the low-power mode is deactivated after it has been set, the system will revert to the normal operating mode. Air conditioning system. [Appendix 2] If the operation of the air conditioner is stopped after setting the low-speed operation mode, the control unit will cancel the low-speed operation mode setting. The air conditioning system described in Appendix 1. [Appendix 3] The control unit, when the low-power operation mode is set while the normal operation mode is running, switches to the low-power operation mode. The air conditioning system described in Appendix 1. [Appendix 4] The control unit, when the low-speed operation mode is set while the air conditioner is stopped, starts the low-speed operation mode. The air conditioning system described in Appendix 1. [Appendix 5] The control unit, when the low-speed operation mode is set, the indoor heat exchanger is functioning as an evaporator, and the constant-speed operation control is being performed, and after a predetermined period of time from the start of the constant-speed operation control the room temperature is equal to or greater than the upper limit switching threshold temperature set for switching the control state in that case, switches the control state to the normal operation control. If a predetermined period has elapsed since the execution of the constant-speed operation control, and the room temperature is below the lower limit stop threshold temperature set for stopping the control in that case, the operation of the compressor is stopped. The air conditioning system described in Appendix 1. [Appendix 6] The control unit, when the low-speed operation mode is set, the indoor heat exchanger is functioning as a condenser, and the constant-speed operation control is being performed, and after a predetermined period of time from the start of the constant-speed operation control the room temperature falls below the lower limit switching threshold temperature set for switching the control state in that case, switches the control state to the normal operation control. If a predetermined period has elapsed since the execution of the constant-speed operation control, and the room temperature is equal to or above the upper limit stop threshold temperature set for stopping the control in that case, the operation of the compressor will be stopped. The air conditioning system described in Appendix 1. [Appendix 7] When the low-power operation mode is set, the control unit sets the airflow from the indoor fan to the minimum airflow. The air conditioning system described in Appendix 1. “Appendix 8” The control unit can variably control the airflow from the indoor fan while the constant-speed operation control is being performed. The air conditioning system described in Appendix 1. [Explanation of Symbols]

[0156] 1...Air conditioning unit, 10...Indoor unit, 22...Heat exchanger (indoor heat exchanger), 23...Fan (indoor blower fan), 80...Indoor unit control unit, 120...Outdoor unit, 122...Heat exchanger (outdoor heat exchanger), 123...Fan (outdoor blower fan), 124...Four-way valve, 125...Compressor, 180...Outdoor unit control unit.

Claims

1. An indoor unit including an indoor heat exchanger and an indoor blower fan, An outdoor unit including an outdoor heat exchanger and an outdoor blower fan, The indoor heat exchanger and the outdoor heat exchanger are connected, and a refrigerant pipe through which the refrigerant flows is provided. A compressor is provided in the outdoor unit, capable of variably controlling the operating frequency and for compressing the refrigerant, An expansion valve provided in the outdoor unit, A control unit that performs air conditioning operation based on the refrigerant flow pattern, Equipped with, The control unit, A normal operation mode is performed to control the operating frequency of the compressor according to the set temperature set in the indoor unit and the room temperature in which the indoor unit is installed, thereby blowing out conditioned air from the indoor unit. A low-speed operation mode is possible, in which the operating frequency of the compressor is controlled to be constant at an operating frequency lower than the maximum operating frequency in the normal operation control, thereby performing constant-speed operation control to blow out conditioned air from the indoor unit. The user can set the low-speed operation mode. When this low-speed operation mode is set, regardless of the airflow setting of the indoor fan, the airflow from the indoor fan is set to the minimum default value in the initial state of the constant-speed operation control. During the execution of the constant-speed operation control, the airflow from the indoor fan can be variably controlled based on the user's instructions. If the low-speed operation mode is canceled after it has been set, the system returns to the normal operation mode. Air conditioning system.

2. If the operation of the air conditioner is stopped after setting the low-speed operation mode, the control unit will cancel the low-speed operation mode setting. The air conditioning device according to claim 1.

3. The control unit, when the low-power operation mode is set while the normal operation mode is running, switches to the low-power operation mode. The air conditioning device according to claim 1.

4. The control unit, when the low-speed operation mode is set while the air conditioner is stopped, starts the low-speed operation mode. The air conditioning device according to claim 1.

5. The control unit, when the low-speed operation mode is set, the indoor heat exchanger is functioning as an evaporator, and the constant-speed operation control is being performed, and after a predetermined period of time from the start of the constant-speed operation control the room temperature is equal to or greater than the upper limit switching threshold temperature set for switching the control state in that case, switches the control state to the normal operation control. If a predetermined period has elapsed since the execution of the constant-speed operation control, and the room temperature is below the lower limit stop threshold temperature set for stopping the control in that case, the operation of the compressor is stopped. The air conditioning device according to claim 1.

6. The control unit, when the low-speed operation mode is set, the indoor heat exchanger is functioning as a condenser, and the constant-speed operation control is being performed, and after a predetermined period of time from the start of the constant-speed operation control the room temperature falls below the lower limit switching threshold temperature set for switching the control state in that case, switches the control state to the normal operation control. If a predetermined period has elapsed since the execution of the constant-speed operation control, and the room temperature is equal to or above the upper limit stop threshold temperature set for stopping the control in that case, the operation of the compressor is stopped. The air conditioning device according to claim 1.

Images