WO2018042515A1

WO2018042515A1 - Air conditioning device

Info

Publication number: WO2018042515A1
Application number: PCT/JP2016/075325
Authority: WO
Inventors: 芸青范; 恵美竹田; 怜司森岡; 淳一岡崎; 正樹豊島
Original assignee: 三菱電機株式会社
Priority date: 2016-08-30
Filing date: 2016-08-30
Publication date: 2018-03-08
Also published as: JPWO2018042515A1; CN109642747B; EP3508795A1; JP6727312B2; CN109642747A; EP3508795B1; EP3508795A4

Abstract

An air conditioning device (101) includes a refrigerant circuit (102), a piping temperature sensor (111), an indoor blower (113), an air conditioning load detection section (125), and a control device (130). The piping temperature sensor (111) detects a condensation temperature (CT). The indoor blower (113) regulates the amount of air flow delivered to an indoor heat exchanger (115). The air conditioning load detection section (125) detects an air conditioning load. The control device (130) has an operation mode having a first mode and a second mode different from the first mode, and the control device (130) controls the amount of air flow delivered by the indoor blower (113). In the second mode, the control device (130) operates the indoor blower (113) so that, as the condensation temperature changes, the amount of air flow will change between a first air flow amount and a second air flow amount which is greater than the first air flow amount. If, during the first mode, an air conditioning load detected by the air conditioning load detection section (125) decreases to a level below a first threshold, the control device (130) changes the operation mode from the first mode to the second mode.

Description

Air conditioner

The present invention relates to an air conditioner, and more particularly to air blow control of an indoor unit.

In the heating operation of the air conditioner, warm air moves upward because its specific gravity is light, so the floor temperature tends to decrease. Therefore, in the conventional heating operation of the air conditioner, comfort is enhanced by conveying warm air to the feet using a fan. In order to further improve comfort during heating, for example, an air conditioner as disclosed in Japanese Patent Application Laid-Open No. 2010-60250 (Patent Document 1) has been proposed.

The air conditioner described in Japanese Patent Application Laid-Open No. 2010-60250 provides a more efficient and comfortable air-conditioned space by controlling the direction and amount of air flow according to the position of the person in the room and the intention of the user. is doing.

JP 2010-60250 A

Currently, houses are becoming more airtight and highly insulated, and the heating load tends to decrease. In a situation where the heating load is small, the heating capacity is also limited to be small. In the air conditioner described in JP 2010-60250 A, the following problems occur.
(1) When the heating capacity of the indoor heat exchanger is small, the temperature of the air conveyed to the foot is lowered because the temperature of the blown air is lowered when the amount of blown air is secured.
(2) When the amount of blown air is reduced, the temperature of the blown air rises, but since the amount of air is small, the blown air (warm air) with a low specific gravity rises due to the cold air with a high specific gravity, and the hot air cannot be conveyed to the feet.

The present invention has been made to solve the above problems. An object of the present invention is to provide an air conditioner capable of supplying warm air to a foot by controlling a fan of an air conditioner in order to make the indoor air temperature uniform during a heating operation at a low load. .

An air conditioner according to the present invention includes a refrigerant circuit, a condensing temperature detection unit, a blower, an air conditioning load detection unit, and a control device. In the refrigerant circuit, the refrigerant circulates in the order of the compressor, the condenser, the expansion mechanism, and the evaporator. The condensing temperature detector is configured to detect a condensing temperature that is a refrigerant temperature in the condenser. The blower is configured to adjust the amount of air blown to the condenser. The air conditioning load detection unit is configured to detect the air conditioning load of the air conditioned space. The control device has a first mode and a second mode that is different from the first mode as operation modes, and is configured to control the air flow rate of the blower. In the second mode, the control device is configured to operate the blower so as to change the air volume between the first air volume and the second air volume larger than the first air volume in accordance with the change in the condensation temperature. The control device is configured to change the first mode to the second mode when the air conditioning load detected by the air conditioning load detection unit is lower than the first threshold value during the first mode.

According to the present invention, a fan intermittent operation (FIO: Fan Intermittent Operation) is performed during a low-load heating operation, thereby destroying the temperature boundary layer formed near the floor and preventing the warm air from rising. , Can supply warm air to your feet. As a result, it is possible to reduce the temperature vibration at the foot and improve indoor comfort.

It is a figure which shows an example of the air conditioning apparatus 101 in Embodiment 1. FIG. It is a figure which shows an example of arrangement | positioning of the component of the indoor unit 103. FIG. It is a figure which shows an example of the indoor air flow in the FIO control in heating operation. 3 is a flowchart illustrating an example of a control flow in the first embodiment. It is a figure for demonstrating the operation mode switching of step S2. It is a figure for demonstrating the change of the operating frequency of the compressor of step S3. It is a figure which shows an example of the driving | running state of the indoor air blower 113 in Embodiment 1. FIG. It is a figure for demonstrating the change of the condensation temperature in fan intermittent operation (FIO). It is the figure which expanded and showed a part of FIG. FIG. 6 is a diagram illustrating an example of the operation of each unit before and after entering the second mode (FIO) in the first embodiment. It is a figure which shows an example of the control system in Embodiment 2. FIG. FIG. 10 is a diagram illustrating an example of the operation of each unit before and after entering the second mode (FIO) in the second embodiment. It is a figure shown about the difference in the timing which enters 2nd mode (FIO).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a plurality of embodiments will be described. However, it is planned from the beginning of the application to appropriately combine the configurations described in the embodiments. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

[Embodiment 1]
(Configuration of air conditioner 101)
FIG. 1 is a diagram illustrating an example of an air-conditioning apparatus 101 according to Embodiment 1 of the present invention. As shown in FIG. 1, the air conditioning apparatus 101 includes an indoor unit 103, an outdoor unit 104, and a control device 130.

The indoor unit 103 includes an indoor blower 113, an indoor heat exchanger 115, an infrared sensor 110, a pipe temperature sensor 111, and an indoor temperature sensor 121. The outdoor unit 104 includes an outdoor fan 114, an outdoor heat exchanger 116, an expansion valve 117, a four-way valve 118, and a compressor 119. The refrigerant circuit 102 is configured by connecting the outdoor heat exchanger 116, the expansion valve 117, the four-way valve 118, the compressor 119, and the indoor heat exchanger 115 in an annular shape by the refrigerant pipe 120. A heat pump is formed by circulating the refrigerant in the refrigerant circuit 102 while repeating compression and expansion. The control device 130 controls the four-way valve 118, the compressor 119, the

blowers

113 and 114, etc., so that the air conditioner 101 air-conditions the room in an operation mode such as cooling / heating / blowing.

FIG. 1 shows a state where the four-way valve 118 is set to heating. In this case, in the four-way valve 118, the port H and the port G communicate with each other, and the port E and the port F communicate with each other. The refrigerant flows from the discharge port B of the compressor 119 in the order of the indoor heat exchanger 115, the expansion valve 117, and the outdoor heat exchanger 116, and reaches the suction port A of the compressor 119.

Although not shown, at the time of cooling, in the four-way valve 118, the port H and the port E communicate with each other, and the port G and the port F communicate with each other. The refrigerant flows from the discharge port B of the compressor 119 in the order of the outdoor heat exchanger 116, the expansion valve 117, and the indoor heat exchanger 115, and reaches the suction port A of the compressor 119.

(Configuration of indoor unit 103)
FIG. 2 is a diagram illustrating an example of an arrangement of components of the indoor unit 103 according to the first embodiment. The indoor unit 103 includes an indoor heat exchanger 115, an indoor blower 113, a pipe temperature sensor 111, an infrared sensor 110, and a wind direction plate (louver) 112 inside the main body. The indoor heat exchanger 115 is disposed on the upstream side of the air flow of the indoor blower 113.

The blowout port forms a ventilation path on the downstream side of the indoor blower 113. The direction of the airflow can be adjusted by changing the angle of the wind direction plate (louver) 112 attached to the outlet.

(Equipment operation for heating operation)
The indoor space is cooled and heated by cold air and hot air blown from the indoor unit 103 of the air conditioner 101. The air conditioner 101 is equipped with a vapor compression refrigeration cycle, and the indoor unit 103 and the outdoor unit 104 are connected by a refrigerant pipe 120.

The compressor 119 compresses the low-temperature / low-pressure refrigerant and discharges the high-temperature / high-pressure refrigerant from the discharge port B. The compressor 119 is driven by an inverter (not shown), and the operation capacity is controlled in accordance with the air condition.

The outdoor heat exchanger 116 performs heat exchange between cold / hot heat supplied from the refrigerant flowing through the refrigeration cycle and outdoor air. As described above, outdoor air is supplied to the outdoor heat exchanger 116 by the outdoor blower 114. The expansion valve 117 is connected between the indoor heat exchanger 115 and the outdoor heat exchanger 116, and decompresses and expands the refrigerant. The expansion valve 117 is configured by a valve whose opening degree can be variably controlled, for example, an electronic expansion valve. The four-way valve 118 is connected to the discharge port B and the suction port A of the compressor 119, and switches the flow of the refrigerant according to the operation (cooling operation, heating operation) of the air conditioner 101.

(Indoor fan 113, outdoor fan 114)
The outdoor blower 114 is a fan capable of varying the flow rate of air supplied to the outdoor heat exchanger 116 and the indoor blower 113 to the indoor heat exchanger 115, respectively. As these fans, a centrifugal fan or a multiblade fan driven by a motor such as a DC fan motor can be used.

<Device operation>
In the present embodiment, FIO (Fan Intermittent Operation) control is performed in order to improve the comfort of the foot when the heating load is small. The FIO control is a control in which an air flow that delivers warm air to the feet is generated by the fan. In the following description, the operation mode in which the air volume is determined by the setting of the user's remote controller or the like is described as a normal operation mode (hereinafter referred to as a first mode (FCO: Fan Common Operation)), and the air conditioning load is low An operation mode in which the fan is intermittently operated is referred to as an intermittent operation mode (hereinafter, second mode (FIO)).

FIG. 3 is a diagram illustrating an example of an indoor air flow in FIO control in the heating operation in the first embodiment. Referring to FIGS. 1 to 3, when the heating load in air-conditioning target space R is small, control device 130 changes the angle of wind direction plate (louver) 112 to make the blowing direction of indoor unit 103 downward. .

When the condensation temperature CT detected by the pipe temperature sensor 111 installed in the indoor heat exchanger 115 is equal to or higher than a certain value (T1), the control device 130 starts the operation of the indoor blower 113 at the fan rotation speed (N2). . When the condensation temperature CT detected by the pipe temperature sensor 111 becomes lower than a certain value (T2), the control device 130 stops the indoor blower 113 or operates with a low air volume. At this time, the control device 130 continues the operation of the compressor 119 regardless of the operation of the indoor blower 113.

Therefore, while the indoor blower 113 is stopped or operating at a low air volume, the surface temperature of the indoor heat exchanger 115 rises, and when the condensation temperature detected by the pipe temperature sensor 111 becomes a certain value (T1) or more again, The indoor blower 113 resumes operation at the rotational speed (N2).

<Control action>
About the air conditioner comprised as mentioned above, operation | movement is demonstrated using a flowchart. FIG. 4 is a flowchart showing an example of a control flow in the first embodiment of the present invention. The control device 130 that executes the processing of this flowchart can be realized by hardware such as a circuit device that realizes these functions, or is read from a memory by a calculation device such as a microcomputer or a CPU and executed by the calculation device. It can also be realized as software.

Referring to FIG. 4, when the processing of this flowchart is started, first, in step S1, control device 130 detects air conditioning load Q (kW). For example, when determining whether the air-conditioning load Q is lower than a predetermined value Q2, the surface temperature of an object (wall, floor, person, etc.) existing in the air-conditioned space can be used as a guide.

The air conditioning load detection unit 125 detects the surface temperature (radiation temperature Tr) of an object existing in the air conditioned space by the infrared sensor 110. When the surface temperature falls below the first threshold value (YES in S2), control device 130 changes the first mode (FCO) to the second mode (FIO).

In another example, the air conditioning load Q is estimated based on the indoor radiation temperature Tr detected by the infrared sensor 110 shown in FIG. The infrared sensor 110 may detect the radiation temperature Tr at a plurality of locations in the room. In such a case, a weighted average value can be used. For example, the relationship between the radiation temperature Tr and the air conditioning load Q may be a predetermined map, and the air conditioning load Q may be obtained from the radiation temperature Tr with reference to the map in step S1.

Furthermore, when estimating the air conditioning load Q, the temperature difference between the outside air temperature and the room temperature, the difference between the floor surface temperature or the room temperature and the set temperature, the amount of solar radiation, the room temperature, etc. may be taken into consideration.

Subsequently, in step S2, the control device 130 determines whether or not the case where the air conditioning load Q is lower than the predetermined value Q2 (Q <Q2). If Q <Q2 is satisfied in step S2 (YES in S2), the process proceeds to step S3. If not satisfied (NO in S2), the process proceeds to step S14.

FIG. 5 is a diagram for explaining the operation mode switching in step S2. Referring to FIG. 5, the condition that air conditioning load Q estimated by infrared sensor 110 using radiation temperature is lower than a predetermined value Q2 (Q <Q2) is that air conditioner 101 enters the second mode (FIO). It is a condition. The condition that the air conditioning load Q is lower than the predetermined value Q1 (Q <Q2) is a condition for stopping the compressor.

Thus, by comparing the air conditioning load Q with the predetermined value Q2 that is the determination value, the control device 130 switches the operation mode between the second mode (FIO) and the first mode (FCO) as appropriate.

In the example of FIG. 1, the air conditioning load detection unit 125 determines the air conditioning load based on the indoor surface temperature or the radiation temperature, but even if the air conditioning load is determined based on the rotational speed of the compressor 119. good. In this case, the air conditioning load detection unit 125 detects the rotation speed of the compressor 119, and the control device 130 detects that the rotation speed of the compressor 119 is lower than the first threshold value (the lower limit set value F1 for normal operation). In addition, the first mode (FCO) is changed to the second mode (FIO).

When the process proceeds from step S2 to step S3, the control device 130 also changes the operating frequency of the compressor 119. FIG. 6 is a diagram for explaining changes in the operating frequency of the compressor in step S3. 4 and 6, in step S3, control device 130 sets the operation frequency of the compressor to an operation frequency F2 that is about half of the lower limit frequency F1 in the normal operation. That is, when changing from the first mode (FCO) to the second mode (FIO) at time t1, the operating frequency of the compressor 119 is a frequency F2 that is about a half of the frequency F1 from the frequency F1 that is the lower limit set value in the normal operation. To change. Further, if the air conditioning load Q is greater than or equal to the predetermined value Q2 in step S2, the operation frequency is returned to the frequency F1 at time t2 because the operation shifts to the first mode (FCO).

In step S3, the control device 130 changes the blowing direction of the indoor blower 113 simultaneously with the change of the operating frequency of the compressor 119. In order to change the blowing direction, the air conditioner 101 includes a wind direction plate (louver) 112. Then, when the mode is the second mode (FIO), the control device 130 controls the wind direction plate 112 so that the blowing direction becomes a predetermined wind direction (corresponding to the angle θ2).

The control device 130 changes the angle θ of the wind direction plate (louver) 112 to an arbitrary angle θ1 set by the user in the first mode (FCO), but changes it to the angle θ2 in the second mode (FIO). Here, as shown in FIG. 2, when the angle θ of the wind direction plate (louver) 112 is 90 ° in the vertical direction and 0 ° in the horizontal direction, the angle θ2 indicating the predetermined wind direction is 45 ° or more. It is. Preferably, the angle θ2 is in the range of 60 to 85 °.

Hereinafter, following step S3, in steps S4 to S10, processing for intermittently operating the indoor fan 113 is executed.

FIG. 7 is a diagram illustrating an example of an operating state of the indoor blower 113 in the first embodiment. During the heating low-capacity operation of the air conditioner, the angle θ of the wind direction plate (louver) 112 is turned downward, and the air volume is intermittently increased or decreased between the first air volume and the second air volume as shown at times t1 to t2. The fan rotation speed has a setting of the rotation speed N2 and a setting of 0 (rpm). The timing for switching the rotation speed from N2 to 0 and the timing for switching from 0 to N2 are determined based on the condensation temperature CT of the indoor heat exchanger 115. Is done.

In the example shown in FIG. 7, the second air volume is the air volume corresponding to the rotational speed N2, and the first air volume is the air volume corresponding to the state where the indoor blower 113 is stopped (air volume = 0). However, the first air volume may be an air volume smaller than the second air volume, and is not necessarily zero.

FIG. 8 is a diagram for explaining a change in the condensation temperature during the second mode (FIO). As the determination value of the condensation temperature CT for operating / stopping the indoor blower 113, two types of temperature T1 and temperature T2 are set. During the second mode (FIO), the condensation temperature CT changes up and down between the temperature T1 and the temperature T2. The indoor blower 113 stops at the rising time tr, and the indoor blower 113 operates at the falling time tf.

FIG. 9 is an enlarged view of a part of FIG. While the indoor blower 113 is stopped, the condensation temperature CT of the indoor heat exchanger 115 rises from T2 to T1.

At time t3, when the condensation temperature CT reaches the temperature T1, the indoor fan 113 starts operation. During the operation of the indoor fan 113 from time t3 to t4, the indoor heat exchanger 115 is cooled by the air blowing, so that the condensation temperature CT decreases from T1 to T2. When the condensation temperature CT decreases to the temperature T2 at time t4, the indoor blower 113 stops. Thereafter, the start and stop of the operation of the indoor blower 113 are repeated at times t5 and t6.

As shown in FIG. 9, in the second mode (FIO), the control device 130 changes the air volume of the indoor blower 113 from the first air volume (fan rotational speed = N2) when the condensation temperature CT becomes higher than the first temperature T1. Change to 2 air volume (fan speed = 0). Further, when the condensing temperature CT becomes lower than the second temperature T2 (<T1), the control device 130 changes the air volume of the indoor blower 113 from the second air volume (fan rotation speed = 0) to the first air volume (fan rotation speed = N2). change.

The blower fan ON / OFF control based on the condensation temperature is executed in steps SS4 to S10 in FIG. Hereinafter, returning to FIG. 4 again, the control will be described.

Following step S3, in step S4, the control device 130 detects the condensation temperature CT by the pipe temperature sensor 111.

Subsequently, in step S5, the control device 130 determines whether or not the indoor fan 113 is in operation (= ON). In step S5, if the indoor fan 113 is ON (YES in S5), the process proceeds to step S6. If the indoor fan 113 is OFF (NO in S5), the process proceeds to step S8. .

In step S6, the control device 130 determines whether or not the condensing temperature CT measured using the pipe temperature sensor 111 is lower than a predetermined value T2. If CT <T2 is established in step S6 (YES in S6), control device 130 stops indoor blower 113 in step S7 and proceeds to step S10. If CT <T2 is not satisfied in step S6 (NO in S6), control device 130 proceeds to step S10 without executing step S7.

On the other hand, in step S8, the control device 130 determines whether or not the condensation temperature CT measured using the pipe temperature sensor 111 is higher than a predetermined value T1. If CT> T1 is established in step S8 (YES in S8), control device 130 causes indoor fan 113 to operate in step S9, and proceeds to step S10. If CT> T1 is not satisfied in step S8 (NO in S8), control device 130 proceeds to step S10 without executing step S9.

In step S10, the control device 130 detects the room temperature Ta by the room temperature sensor 121. If room temperature Ta is higher than predetermined value Ta_min (YES in S11), control device 130 advances the process to step S12. When room temperature Ta is lower than predetermined value Ta_min (NO in S11), control device 130 advances the process to step S14.

In step S12, the control device 130 detects the human body temperature Ta_t. As a standard of the sensory temperature, the indoor surface temperature can be measured using the infrared sensor 110, and this can be used as the sensory temperature Ta_t.

When the sensory temperature Ta_t is higher than the predetermined value Ta_set (YES in S13), the control device 130 returns the process to step S1 and repeats the above-described operation. When the sensory temperature Ta_t is lower than the predetermined value Ta_set (NO in S13), the control device 130 advances the process to step S14. In step S14, the control device 130 sets the operation mode to the first mode (FCO), and causes the air conditioner 101 to operate normally.

The normal operation executed in the first mode may be different from the indoor fan intermittent operation in which the processes in steps S3 to S13 are repeated. Various processes may be used as long as the process controls the air volume and room temperature according to user settings. Driving is assumed.

In steps S11 and S13, it is determined whether to switch the operation mode from the second mode to the first mode. That is, the air-conditioning load detection unit 125 of FIG. 1 includes an infrared sensor 110 that detects the surface temperature of an object that exists in the air-conditioned space, and an indoor temperature sensor 121 that detects the indoor temperature. During operation in the second mode (FIO), the control device 130 has a first condition that the room temperature Ta is lower than the second threshold Ta_min, and the surface temperature (sensory temperature Ta_t) is higher than the third threshold Ta_set. When at least one of the second conditions of low is satisfied, the operation mode is changed from the second mode (FIO) to the first mode (FCO).

FIG. 10 is a diagram illustrating an example of the operation of each part before and after entering the second mode (FIO) in the first embodiment. From time t0 to t1, normal operation (FCO) during heating is performed. At this time, the rotation speed of the indoor blower 113 is the rotation speed N1 determined by the user setting.

When the normal operation (FCO) is changed to the low load operation (FIO) at the time t1, the rotational speed N of the indoor blower 113 is intermittently switched between 0 and N2, and the wind direction plate (louver) 112 is set to an arbitrarily set arbitrary value. The angle θ1 is changed to a predetermined angle θ2 (= 60 to 85 °), and the operating frequency of the compressor 119 is changed from the frequency F1 corresponding to the lower limit value of the normal operation to a frequency F2 that is about half of that.

In this way, the control of causing the indoor fan 113 to operate intermittently while fixing the operating frequency of the compressor 119 destroys the natural temperature boundary layer of the air formed near the floor and prevents the warm air from rising. , Reduce the vibration of the foot temperature.

Referring again to FIG. 1 and the like, the air conditioner 101 according to Embodiment 1 will be summarized. The air conditioner 101 includes a refrigerant circuit 102, a pipe temperature sensor 111, an indoor fan 113, an air conditioning load detection unit 125, and a control device 130. During heating in the refrigerant circuit 102, the refrigerant circulates in the order of the compressor 119, the indoor heat exchanger 115 that functions as a condenser, the expansion valve 117, and the outdoor heat exchanger 116 that functions as an evaporator. The pipe temperature sensor 111 is configured to detect a condensation temperature CT which is a refrigerant temperature in the indoor heat exchanger 115. The indoor blower 113 is configured to adjust the heat radiation amount of the indoor heat exchanger 115. The air conditioning load detection unit 125 is configured to detect the air conditioning load of the air conditioned space.

As represented by the flowchart of FIG. 4 and the waveform diagram of FIG. 10, the control device 130 has a first mode (FCO) and a second mode (FIO) different from the first mode as operation modes, It is comprised so that the ventilation volume of the indoor air blower 113 may be controlled. In the second mode, the control device 130 causes the indoor blower 113 to change the air volume between the first air volume (zero) and the second air volume (N2) greater than the first air volume in accordance with the change in the condensation temperature CT. Configured to drive. As shown in FIG. 5, when the air conditioning load Q detected by the air conditioning load detection unit 125 is lower than the first threshold value Q2 during the first mode, the control device 130 performs the first mode (FCO). Is configured to change to the second mode (FIO).

With the air conditioner 101 according to Embodiment 1, the following effects (1) to (3) can be obtained.
(1) By stopping the fan and raising the condensation temperature, it is possible to raise the blowing temperature even at low frequency operation of the compressor. Also, warm air can be supplied to the feet when the fan is restarted.
(2) By making the wind direction plate face down, the direction of the warm air can be used as a foot. Further, due to the temperature difference between the blown warm air and the indoor air, the warm air moves from the bottom to the top after being sent to the feet. For this reason, the room temperature can be made uniform even in the low frequency operation of the compressor.
(3) Since the room temperature can be kept uniform even when the operation frequency of the compressor is low, the start / stop of repeated operation / stop of the compressor is suppressed, and an energy saving effect can be expected.

[Embodiment 2]
The second embodiment of the present invention will be described below. The air-conditioning apparatus according to Embodiment 2 includes a control device that controls a plurality of indoor units 103 in order to set the indoor temperature of the air-conditioning target space R as a target temperature. Since the control of the load detection means, the temperature detection means, the air blow control means, and the wind direction control means of each indoor unit 103 is the same as that of the first embodiment, illustration and description thereof are omitted.

FIG. 11 is a diagram illustrating an example of a control system according to the second embodiment.

Indoor units

103A, 103B, and 103C are connected to centralized control device 230 by

communication devices

203, 204, and 205, respectively. It is possible to control the

indoor units

103A, 103B, and 103C from the centralized control device 230. The connection between the

indoor units

103A, 103B, and 103C and the

communication devices

203, 204, and 205, and the connection between the

communication devices

203, 204, and 205 and the central control device 230 may be wired or wireless. To communicate to.

FIG. 12 is a diagram illustrating an example of the operation of each part before and after entering the second mode (FIO) in the second embodiment. Control of the load detection means, temperature detection means, air blow control means, and wind direction control means of the

indoor units

103A, 103B, 103C is the same as that of the first embodiment as shown in FIG. However, the second embodiment is characterized in that the timings at which the

indoor units

103A, 103B, and 103C enter the second mode (FIO) are slightly different from each other.

FIG. 13 is a diagram illustrating a difference in timing of entering the second mode (FIO). As shown in FIG. 13, the timing when the indoor unit 103B enters the second mode (FIO) is delayed by the time difference FIOΔT from the timing when the indoor unit 103A enters the second mode (FIO). When this time difference, fan rotation speed, and temperature T1, T2 settings are adjusted, warm air blows out from the other

indoor units

103B or 103C during the fan stop time of the indoor unit 103A.

That is, in the second embodiment, as simply shown in FIG. 11, the indoor heat exchanger 115 includes a first condenser 115A and a second condenser 115B connected in parallel to each other in the refrigerant circuit. The indoor blower 113 includes a first blower 113A and a second blower 113B that are provided corresponding to the first condenser 115A and the second condenser 115B, respectively. As shown in FIG. 13, in the second mode (FIO), the central control device 230 is configured such that the first air blower 113A blows the second air flow (fan rotation speed N2A) and the second air blower 113B is the second air flow (fan). The first blower 113A and the second blower 113B are controlled so that the period during which the rotational speed N2B) is blown does not overlap. Although not shown, the indoor unit 103C is similarly provided with a condenser and a blower.

By controlling in this way, the air is alternately blown from the blowers of a plurality of indoor units, so that warm air is always supplied to the feet, and temperature vibrations near the floor surface can be suppressed.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

101 air conditioner, 103, 103A, 103B, 103C indoor unit, 104 outdoor unit, 110 infrared sensor, 111 piping temperature sensor, 113 indoor fan, 114 outdoor fan, 115 indoor heat exchanger, 116 outdoor heat exchanger, 117 expansion Valve, 118 four-way valve, 119 compressor, 120 refrigerant piping, 121 indoor temperature sensor, 130 control device, 230 central control device, 203 communication device.

Claims

A refrigerant circuit in which the refrigerant circulates in the order of the compressor, the condenser, the expansion mechanism, and the evaporator;
A condensing temperature detector configured to detect a condensing temperature that is a refrigerant temperature in the condenser;
A blower configured to adjust the air flow to the condenser;
An air conditioning load detector configured to detect an air conditioning load; and
A control device configured to control the air flow rate of the blower having a first mode and a second mode different from the first mode as an operation mode;
In the second mode, the control device is configured to operate the blower so that the air volume is changed between the first air volume and the second air volume larger than the first air volume in accordance with the change in the condensation temperature. And
The control device changes the first mode to the second mode when the air conditioning load detected by the air conditioning load detection unit is lower than a first threshold value during the first mode. An air conditioner configured as described above.
The air-conditioning load detection unit detects the temperature of the air-conditioned space,
The air conditioning apparatus according to claim 1, wherein the control device changes the first mode to the second mode when the temperature falls below the first threshold value.
The air conditioning load detector is
A surface temperature detector for detecting the surface temperature of an object present in the air-conditioned space;
Including an indoor temperature detector for detecting the indoor temperature,
During the operation in the second mode, the control device has at least a first condition that the room temperature is lower than a second threshold value and a second condition that the surface temperature is lower than a third threshold value. The air conditioning apparatus according to claim 1, wherein when one of the conditions is established, the operation mode is changed from the second mode to the first mode.
The air conditioning load detection unit detects the rotation speed of the compressor,
The air conditioner according to claim 1, wherein the control device changes the first mode to the second mode when the rotational speed of the compressor is lower than the first threshold value.
A wind direction changing unit for changing a blowing direction of the blower;
The air conditioner according to claim 1, wherein the control device controls the wind direction changing unit so that the air blowing direction becomes a predetermined wind direction when the mode is the second mode.
The air conditioner according to claim 5, wherein when the angle indicating the vertical direction with respect to the floor surface is 90 ° and the angle indicating the horizontal direction is 0 °, the angle indicating the predetermined wind direction is 45 ° or more. apparatus.
In the second mode, when the condensing temperature becomes higher than the first temperature, the control device changes the air flow rate of the blower from the first air volume to the second air volume, and from a second temperature lower than the first temperature. 2. The air conditioner according to claim 1, wherein when the condensing temperature is lowered, the air volume of the blower is changed from the second air volume to the first air volume.
The air conditioner is
An additional condenser connected in parallel to the condenser in the refrigerant circuit;
An additional blower provided corresponding to the additional condenser,
In the second mode, the control device is configured such that the period in which the blower blows the second air volume and the period in which the additional blower blows the second air volume do not overlap with each other. The air conditioning apparatus according to claim 1, wherein the air conditioner is controlled.
The air conditioner according to any one of claims 1 to 8, wherein the first air volume is an air volume corresponding to a state in which the blower is stopped.