JP6656400B2 - Air conditioner indoor unit and air conditioner - Google Patents

Description

  The present invention relates to an indoor unit of an air conditioner and an air conditioner.

  BACKGROUND ART Conventionally, an air conditioner that controls the number of revolutions of a compressor and the number of revolutions of an indoor blower based on an indoor temperature has been proposed (for example, see Patent Document 1). The air conditioner described in Patent Literature 1 reduces the number of revolutions of the compressor and the number of revolutions of the indoor blower when the room temperature reaches the target temperature.

JP-A-60-1088638

  During the heating operation, if the condensing temperature of the heat exchanger mounted in the indoor unit is high, high-temperature air is supplied from the indoor unit to the room accordingly. In such a situation, the room temperature may exceed the target temperature and the room may be warmed more than necessary, and the energy saving performance of the air conditioner may be reduced.

  SUMMARY An advantage of some aspects of the invention is to provide an air conditioner indoor unit and an air conditioner that can improve energy saving.

The indoor unit of the air conditioner according to the present invention detects a first heat exchanger that functions as a condenser, a blower that supplies air to the first heat exchanger, and a condensation temperature of the first heat exchanger. comprising a condensation temperature sensor for the air volume setting unit that accepts a set air volume, and a control device for controlling the blower based on the condensation temperature detected set air volume and the condensation temperature sensor transmitted from the air volume setting unit, the control If the condensing temperature is lower than the first temperature during the heating operation , the device operates the blower at the current set rotation speed of the blower, and performs the condensing temperature during the heating operation. If the temperature is equal to or higher than the predetermined temperature, the current set rotation speed of the blower is reduced according to the size of the condensing temperature and is reduced to a corrected rotation speed smaller than the current set rotation speed. It is configured to, the heating operation If the condensing temperature is equal to or higher than the first temperature and lower than the second temperature higher than the first temperature during execution, the condensing temperature corresponds to the corrected rotational speed and is lower than the current set rotational speed. When the blower is operated at the first rotation speed and the set airflow is the second set airflow smaller than the first set airflow than the first rotation speed when the set airflow is the first set airflow If the condensing temperature is higher than the second temperature and lower than the third temperature higher than the second temperature when the heating operation is being performed, The blower is operated at a second rotation speed corresponding to the rotation speed, which is lower than the first rotation speed, and the set airflow is smaller than the second rotation speed when the set airflow is the first set airflow. The second rotation speed in the case of the set airflow is smaller .

  According to the present invention, since the above-described configuration is provided, energy saving can be improved.

It is an explanatory view of a refrigerant circuit of an air conditioner provided with an indoor unit according to the present embodiment. It is a functional block diagram of the control device of the air conditioner provided with the indoor unit which concerns on this Embodiment. FIG. 9 is an explanatory diagram of a table used when correcting the number of rotations currently set for the first blower. FIG. 4 is an explanatory diagram of a control flow of the air-conditioning apparatus including the indoor unit according to the present embodiment. It is explanatory drawing of the time change of indoor temperature, and the time change of the rotation speed of a blower. 9 is a modified example of the control flowchart shown in FIG. 3. 5 is a modification example of the refrigerant circuit shown in FIG. 1.

Embodiment.
An air conditioner 100 according to the present embodiment will be described.
FIG. 1 is an explanatory diagram of a refrigerant circuit C of the air-conditioning apparatus 100 according to the present embodiment.

[Description of configuration]
As shown in FIG. 1, the air conditioner 100 includes a refrigerant circuit C for circulating a refrigerant.
The air conditioner 100 includes an outdoor unit 101 and an indoor unit 102. The air conditioner 100 is a so-called separate type air conditioner in which an outdoor unit 101 and an indoor unit 102 are separated. Note that the outdoor unit 101 and the indoor unit 102 are connected via a refrigerant pipe P1 and a refrigerant pipe P2. Further, the outdoor unit 101 is provided with a valve Va to which the refrigerant pipe P1 and the refrigerant pipe P2 are connected. The indoor unit 102 is also provided with a valve Va to which the refrigerant pipe P1 and the refrigerant pipe P2 are connected.

The refrigerant circuit C includes a compressor 1, a four-way valve 2, a throttle device 4, a first heat exchanger 5, a second heat exchanger 3, a refrigerant pipe P1, and a refrigerant pipe P2. Further, the air conditioner 100 includes a second blower 3A attached to the second heat exchanger 3 and a first blower 5A attached to the first heat exchanger 5.
The outdoor unit 101 is equipped with a compressor 1, a four-way valve 2, a second heat exchanger 3, a second blower 3A, and a throttle device 4. The indoor unit 102 is equipped with a first heat exchanger 5 and a first blower 5A.

  The air conditioner 100 includes a control device 50 that performs overall control of the outdoor unit 101 and the indoor unit 102. In addition, in FIG. 1, the control device 50 is mounted on the indoor unit 102, but is not limited thereto. The air-conditioning apparatus 100 may be configured such that the control device is mounted on each of the outdoor unit 101 and the indoor unit 102, and these control devices communicate with each other.

  The air conditioner 100 includes an input device RC that issues a control command to the indoor unit 102. The input device RC functions as a remote controller. The air conditioner 100 includes a condensing temperature detecting unit D1 for detecting a condensing temperature of the refrigerant circuit C, and an indoor temperature detecting unit D2 for detecting an indoor temperature.

  The compressor 1 is a fluid machine that compresses the sucked low-pressure refrigerant and discharges the compressed low-pressure refrigerant as high-pressure refrigerant. The rotation speed of the compressor 1 is controlled by, for example, an inverter. The compressor 1 includes a refrigerant discharge unit that discharges a high-pressure refrigerant and a refrigerant suction unit that suctions the low-pressure refrigerant that has returned through the refrigerant circuit C.

  The four-way valve 2 communicates a refrigerant discharge part of the compressor 1 with the second heat exchanger 3 and a first flow which communicates a refrigerant suction part of the compressor 1 with the first heat exchanger 5. A passage, a second flow passage communicating the refrigerant discharge part of the compressor 1 with the first heat exchanger 5, and communicating the refrigerant suction part of the compressor 1 with the second heat exchanger 3. including. The first flow path and the second flow path of the four-way valve 2 are selectively switched by the control device 50. During the cooling operation, the four-way valve 2 is switched to the first flow path, and during the heating operation, the four-way valve 2 is switched to the second flow path.

  The expansion device 4 is, for example, an electronic expansion valve whose opening degree can be adjusted. The expansion device 4 may use other decompression means such as a capillary tube.

  The first heat exchanger 5 can be configured, for example, as an air-cooled heat exchanger that exchanges heat between the refrigerant flowing inside and the air blown by the first blower 5A. The first heat exchanger 5 can be configured as a fin-and-tube heat exchanger. The first heat exchanger 5 functions as an evaporator when the air conditioner 100 is performing a cooling operation, and functions as a condenser when performing a heating operation. The first blower 5A includes an electric motor (not shown) and a fan rotated by the electric motor. The rotation speed of the first blower 5A is controlled such that the amount of air supplied to the first heat exchanger 5 can be variably adjusted. Note that the rotation speed of the first blower 5A is the fan rotation speed of the first blower 5A. In the present embodiment, there are at least seven rotation speeds (air volumes) that can be set for first blower 5A (see FIG. 2B).

  The second heat exchanger 3 can be configured as, for example, an air-cooled heat exchanger that exchanges heat between the refrigerant flowing inside and the air blown by the second blower 3A. The air-cooled heat source-side heat exchanger can be configured as, for example, a cross-fin type fin-and-tube heat exchanger including a heat transfer tube and a plurality of fins. The second heat exchanger 3 functions as a condenser (radiator) when the air-conditioning apparatus 100 is performing the cooling operation, and functions as an evaporator when performing the heating operation.

  The control device 50 controls the compressor 1, the expansion device 4, the second blower 3A, the first blower 5A, and the like. The control device 50 acquires the condensing temperature data transmitted from the condensing temperature detecting unit D1 and the indoor temperature data transmitted from the indoor temperature detecting unit D2. Each functional unit included in the control device 50 is configured by dedicated hardware or an MPU (Micro Processing Unit) that executes a program stored in a memory. When the control device 50 is dedicated hardware, the control device 50 includes, for example, a single circuit, a composite circuit, an ASIC (application specific integrated circuit), an FPGA (field-programmable gate array), or a combination thereof. Applicable. Each of the function units realized by the control device 50 may be realized by individual hardware, or each function unit may be realized by one piece of hardware. When the control device 50 is an MPU, each function executed by the control device 50 is realized by software, firmware, or a combination of software and firmware. Software and firmware are described as programs and stored in a memory. The MPU realizes each function of the control device 50 by reading and executing a program stored in the memory. The memory is, for example, a nonvolatile or volatile semiconductor memory such as a RAM, a ROM, a flash memory, an EPROM, and an EEPROM.

The input device RC can transmit to the indoor unit 102, for example, a control instruction for a heating operation and a cooling operation, a control instruction for an air volume of the air blown from the indoor unit 102, and a control instruction for a set temperature in the room. Is configured. The input device RC may be connected to the indoor unit 102 by wire or wirelessly. Note that the input device RC may be configured by a mobile terminal (for example, a mobile phone) provided with a predetermined application.
The input device RC includes an air volume setting unit RC1 that receives a set air volume, an indoor temperature setting unit RC2 that receives an indoor set temperature, and an operation mode setting unit RC3 that receives various operation modes. The operation mode includes a heating operation, and may also include a cooling operation. The air volume setting unit RC1, the room temperature setting unit RC2, and the operation mode setting unit RC3 can be configured by, for example, buttons operated by a user. The air volume setting unit RC1 is configured to receive a plurality of air volumes. In the present embodiment, the control device 50 includes a first set airflow large air flow (Hi), a second set airflow medium airflow 2 (Mid2), and a third set airflow medium airflow Mid. 1 (Mid1) and a small air volume (Lo) which is a fourth set air volume can be set in four stages. The air volume decreases in the order of large air volume, medium air volume, medium air volume one, and small air volume. The set air volume is not limited to four stages, but may be one to three stages, or five or more stages.

The condensation temperature detection unit D1 includes a first condensation temperature sensor SE1 and a second condensation temperature sensor SE3. The first condensation temperature sensor SE1 and the second condensation temperature sensor SE3 can be constituted by a thermistor or the like. The first condensation temperature sensor SE1 is provided in the first heat exchanger 5 mounted on the indoor unit 102. The first condensation temperature sensor SE1 detects the condensation temperature of the refrigerant during the heating operation in which the first heat exchanger 5 functions as a radiator. On the other hand, the second condensation temperature sensor SE3 is provided in the second heat exchanger 3 mounted on the outdoor unit 101. The second condensation temperature sensor SE3 detects the condensation temperature of the refrigerant during the cooling operation in which the second heat exchanger 3 functions as a radiator. The condensing temperature detected by the first condensing temperature sensor SE1 and the condensing temperature detected by the second condensing temperature sensor SE3 are transmitted from the condensing temperature detecting unit D1 to the control device 50 as condensing temperature data.
The indoor temperature detection unit D2 includes an indoor temperature sensor SE2 that detects an indoor temperature. The indoor temperature detector D2 is provided in the indoor unit 102. The indoor temperature sensor SE2 detects the temperature (indoor temperature) of the air taken into the indoor unit 102 by the operation of the first blower 5A. The indoor temperature sensor SE2 can be constituted by a thermistor or the like. The room temperature detected by the room temperature sensor SE2 is transmitted from the room temperature detection unit D2 to the control device 50 as room temperature data.

[Operation explanation of heating operation and cooling operation]
When performing the cooling operation, the refrigerant compressed by the compressor 1 becomes a high-temperature and high-pressure refrigerant and is supplied to the second heat exchanger 3 through the four-way valve 2. The refrigerant supplied to the second heat exchanger 3 exchanges heat with air to radiate heat and condenses, becomes a high-pressure liquid refrigerant, and is supplied to the expansion device 4. The refrigerant supplied to the expansion device 4 is reduced in pressure to become a low-temperature and low-pressure two-phase refrigerant, and is supplied to the first heat exchanger 5 of the indoor unit 102 through the refrigerant pipe P2. The refrigerant supplied to the first heat exchanger 5 exchanges heat with indoor air, absorbs heat, evaporates and becomes a low-temperature gas refrigerant. At this time, the indoor air is cooled by the refrigerant. Then, the cooled air is supplied into the room from the outlet of the indoor unit 102 by the action of the first blower 5A. The refrigerant that has passed through the first heat exchanger 5 returns to the outdoor unit 101 through the refrigerant pipe P1, and returns to the compressor 1 through the four-way valve 2.

  When performing the heating operation, the refrigerant compressed by the compressor 1 becomes a high-temperature and high-pressure refrigerant and is supplied to the first heat exchanger 5 of the indoor unit 102 through the four-way valve 2 and the refrigerant pipe P1. Then, the refrigerant supplied to the first heat exchanger 5 exchanges heat with air to radiate heat and condense to become a high-pressure liquid refrigerant. At this time, the indoor air is heated. The heated air is supplied into the room from the outlet of the indoor unit 102 by the action of the first blower 5A. The refrigerant that has passed through the first heat exchanger 5 passes through the refrigerant pipe P2, returns to the outdoor unit 101, and is supplied to the expansion device 4. The refrigerant supplied to the expansion device 4 is reduced in pressure to become a low-temperature low-pressure two-phase refrigerant, and is supplied to the second heat exchanger 3. The refrigerant supplied to the second heat exchanger 3 exchanges heat with air, absorbs heat, evaporates and becomes a low-temperature gas refrigerant. Then, the refrigerant that has passed through the second heat exchanger 3 is returned to the compressor 1 through the four-way valve 2.

[About control device 50]
FIG. 2A is a functional block diagram of control device 50 of air-conditioning apparatus 100 according to the present embodiment.
FIG. 2B is an explanatory diagram of a table used when correcting the rotation number currently set to the first blower 5A. The numbers 1 to 7 shown in FIG. 2B indicate the magnitude relationship of the rotation speed of the first blower 5A.

  The control device 50 includes a determination unit 50A (determination of reaching various temperatures), a rotation speed correction unit 50B, a target temperature calculation unit 50C, an output control device 50D, and a storage unit 50E. Although not shown, the control device 50 includes a timer and has a function of measuring time.

(Determination unit 50A)
The determination unit 50A determines whether or not the room has reached the target temperature based on the room temperature data transmitted from the room temperature detection unit D2. In addition, the determination unit 50A determines whether to correct the rotation speed of the first blower 5A based on the condensation temperature data transmitted from the condensation temperature detection unit D1. The determination unit 50A determines that the correction is performed when the condensation temperature specified by the condensation temperature data is equal to or higher than a predetermined temperature, and determines that the correction is not performed when the condensation temperature is lower than the predetermined temperature.

(Rotation speed correction unit 50B)
When the determination unit 50A determines that the rotation speed of the first blower 5A is to be corrected, the rotation speed correction unit 50B calculates a correction value of the rotation speed of the first blower 5A (corrected rotation speed). The rotation speed correction unit 50B calculates the corrected rotation speed according to the size of the condensation temperature specified by the condensation temperature data.

  As shown in FIG. 2B, the rotation speed correction unit 50B calculates the corrected rotation speed using the corrected rotation speed calculation table stored in the storage unit 50E. Here, the mode using the corrected rotational speed calculation table will be described. However, a predetermined arithmetic expression is stored in the storage unit 50E, and correction is performed based on the arithmetic expression, the condensing temperature, and the set air volume. The post-rotation speed may be calculated.

  The rotation speed correction unit 50B is configured to reduce the corrected rotation speed according to the condensation temperature. For example, when the current set air volume is small (Lo), the corrected rotational speed is set as follows. Here, the magnitude of the rotation speed corresponding to the small air volume (Lo) is four. (1) When the condensing temperature is lower than the first temperature T1, the rotation speed corrector 50B determines that the set rotation speed of the first blower 5A is to remain at the current setting rotation speed. (2) When the condensing temperature is equal to or higher than the first temperature T1 and lower than the second temperature T2, the rotation speed correction unit 50B sets the rotation speed of the first blower 5A to the size 4. It is determined to change from the currently set rotation speed to the corrected rotation speed (first rotation speed) having a magnitude of 3. (3) When the condensing temperature is equal to or higher than the second temperature T2 and lower than the third temperature T3, the rotation speed correction unit 50B sets the rotation speed of the first blower 5A to the size 4. It is determined that the currently set rotational speed is to be changed to the corrected rotational speed (second rotational speed) of the magnitude 2. (4) When the condensing temperature is equal to or higher than the third temperature T3, the rotation speed correction unit 50B increases the set rotation speed of the first blower 5A from the current set rotation speed of size 4 It is determined to change to the post-correction rotation speed (third rotation speed) which is 1. In addition, the magnitude is smaller in the order of the current set rotation speed, the first rotation speed, the second rotation speed, and the third rotation speed. When the condensing temperature is lower than the predetermined temperature (first temperature T1) as described above, the rotation speed is not corrected as in the above (1), but the condensing temperature is not higher than the predetermined temperature (first temperature T1). When the temperature is equal to or higher than the first temperature T1), the rotation speed is corrected as described in (2) to (4), and the set rotation speed of the first blower 5A decreases. In the present embodiment, an example has been described in which the corrected rotational speed can be changed to three stages (a first rotational speed, a second rotational speed, and a third rotational speed). Or two or four or more stages.

  The rotation speed correction unit 50B is configured to reduce the corrected rotation speed in accordance with the set airflow of the first blower 5A set by the input device RC. For example, when the current set air volume is a large air volume (Hi) which is the first set air volume, the first rotation speed of the first blower 5A is 6 and the current set air volume is the second Is 2 (Mid2), the first rotational speed of the first blower 5A is 5 and the current set airflow is 1 (mid2), which is the third set airflow. Mid1), the first rotation speed of the first blower 5A is 4 and the first set airflow is the fourth set airflow, the first airflow is small (Lo). The first rotation number of the blower 5A is the magnitude 3. As described above, the smaller the set air volume of the first blower 5A set by the input device RC, the lower the first rotation speed. Similarly, the second rotation speed and the third rotation speed decrease as the set airflow decreases.

  Here, the corrected rotation speed includes a rotation speed lower than the rotation speed corresponding to the minimum airflow among the plurality of set airflows. That is, the control device 50 can operate the first blower 5A with an airflow smaller than the fourth set airflow, which is the minimum set airflow that can be set by the input device RC. The control device 50 and the first blower 5A are configured to be able to operate at a rotation speed smaller than the rotation speed corresponding to the fourth set airflow which is the minimum set airflow. . Thereby, the power consumption of the first blower 5A can be suppressed more reliably, and the energy saving can be improved. The rotation speed described here corresponds to rotation speeds of magnitude 1 to magnitude 3 in FIG. 2B.

(Target temperature calculation unit 50C)
The target temperature calculator 50C calculates a target indoor temperature based on the indoor set temperature data transmitted from the input device RC. The target temperature is usually equal to the set temperature set by the input device RC. Here, for example, if the input device RC is set to execute the powerful operation, the target temperature becomes a value deviated from the set temperature set by the input device RC. For example, when the input device RC is set to execute the heating operation and the powerful operation, the target temperature calculation unit 50C calculates a temperature higher than the set temperature as the target temperature. Accordingly, the difference between the current room temperature and the target temperature increases, so that the air-conditioning apparatus 100 executes an operation with a higher heating capacity. For example, the control device 50 increases the rotation speed of the compressor 1.

(Output control device 50D)
The output control device 50D controls various devices based on the determination result of the determination unit 50A, the calculation result of the rotation speed correction unit 50B, data stored in the storage unit 50E, and the like. The output control device 50D controls at least one of the compressor 1, the expansion device 4, the second blower 3A, and the first blower 5A.

(Storage unit 50E)
Various data are stored in the storage unit 50E. For example, the storage unit 50E stores various data such as condensation temperature data and room temperature data. The storage unit 50E stores a corrected rotation speed calculation table. When the control device 50 uses an arithmetic expression for calculating the corrected rotational speed instead of the corrected rotational speed calculation table, the storage unit 50E stores the arithmetic expression.

[Control flow]
FIG. 3 is an explanatory diagram of a control flow of the air-conditioning apparatus 100 according to the present embodiment.
An example of a control flow of the air-conditioning apparatus 100 will be described with reference to FIG. In this control flow, a heating operation is assumed.

  The target temperature calculator 50C calculates a target temperature based on data (for example, indoor set temperature data) transmitted from the input device RC (Step S1). The control device 50 has acquired the room temperature. Here, the room temperature is specified by room temperature data transmitted from the room temperature detection unit D2. The determination unit 50A compares the target temperature with the room temperature (Step S3). If the absolute value of the value obtained by subtracting the room temperature from the target temperature is equal to or greater than a predetermined value, control device 50 proceeds from step S3 to step S4-1, and if the absolute value is less than the predetermined value, Control device 50 proceeds from step S3 to step S4-2.

  When it is determined that the absolute value of the value obtained by subtracting the room temperature from the target temperature is equal to or greater than a predetermined value, the output control device 50D determines that there is a difference between the target temperature and the room temperature. The rotation speed of the machine 1 is maintained or increased (step S4-1). If the absolute value of the value obtained by subtracting the room temperature from the target temperature is determined to be less than a predetermined value, the output control device 50D determines that the target temperature and the room temperature do not open or is small, The rotation speed of the compressor 1 is reduced (step S4-2).

  The control device 50 acquires the condensation temperature of the first heat exchanger 5. Here, the condensation temperature is specified by the condensation temperature data transmitted from the condensation temperature detection unit D1. The determination unit 50A determines whether to correct the current set rotation speed of the first blower 5A based on the condensation temperature of the second heat exchanger (Step S6).

  If the control device 50 determines that the current set rotation speed of the first blower 5A is to be corrected, the process proceeds to step S7. If the control device 50 determines that the current set rotation speed of the first blower 5A is not to be corrected, the process proceeds to step S7. Return to S1. The rotation speed correction unit 50B calculates the corrected rotation speed based on the condensation temperature of the first heat exchanger 5 and the set airflow of the first blower 5A (Step S7). The output control device 50D operates the first blower 5A at the corrected rotation speed (step S8).

[Time change of indoor temperature and time change of fan rotation speed]
FIG. 4 is an explanatory diagram of the time change of the room temperature and the time change of the rotation speed of the blower.
FIG. 4A shows the transition of the room temperature of the conventional control and the transition of the room temperature of the present embodiment.
FIG. 4B shows the transition of the rotation speed of the second fan of the conventional control.
FIG. 4C shows a transition of the rotation speed of the first blower 5A of the present embodiment.

  As shown in FIG. 4A, in the conventional control, the rotation speed of the second blower does not decrease in accordance with the rise in the condensing temperature, and the room temperature exceeds the set temperature of the input device RC. That is, in the conventional control, the heated air is additionally supplied into the room, and the energy saving is reduced accordingly. On the other hand, in the present embodiment, the number of revolutions of the second blower is decreased in accordance with the increase in the condensing temperature, so that the room temperature approaches the input device RC so as not to exceed the set temperature, thereby improving energy saving. I have.

[Effects of Embodiment]
The indoor unit 102 of the air-conditioning apparatus 100 according to the present embodiment performs the current setting of the first blower 5A when the condensing temperature becomes equal to or higher than a predetermined temperature during the heating operation. The rotation speed is reduced to a corrected rotation speed that is lower than the current set rotation speed. The corrected rotational speed is determined according to the size of the condensation temperature. The higher the condensing temperature, the lower the corrected rotational speed. For this reason, the indoor unit 102 can suppress the power consumption of the first blower 5A because it does not need to supply the excess heated air to the room, and can improve energy saving.

[Modification of Control Flowchart]
FIG. 5 is a modified example of the control flowchart shown in FIG. Note that, here, the description will be made focusing on the differences from the present embodiment, and the same reference numerals will be given to the common components. Steps S1 to S8 in FIG. 5 are the same as steps S1 to S8 in FIG.

  In the present embodiment, the opening degree of the expansion device 4 was not changed in the control shown in FIG. In this modified example, as shown in step S9 of FIG. 5, after step S8, step S9 for increasing the opening degree of the expansion device 4 is added.

  Specifically, the control device 50 is configured to increase the opening degree of the expansion device 4 when the current set rotation speed is reduced to the corrected rotation speed. Thereby, it is possible to prevent the condensation temperature of the first heat exchanger 5 from excessively increasing. That is, when the rotation speed of the first blower 5A is reduced to the rotation speed after the correction, the flow rate of the air supplied to the first heat exchanger 5 is reduced, which may act to increase the condensation temperature. . Then, if the rotation speed of the first blower 5A is reduced to the corrected rotation speed, the condensing temperature increases, and a situation may occur in which the rotation speed of the first blower 5A is further reduced to the corrected rotation speed. . In order to avoid such a situation, in the present modified example, when the currently set rotation speed is reduced to the corrected rotation speed, the opening degree of the expansion device 4 is increased.

  The control device 50 increases the opening degree of the expansion device 4 at the timing of reducing the current set rotation speed to the corrected rotation speed. As a result, the above-described situation can be avoided more reliably. Here, the timing at which the currently set rotational speed is reduced to the corrected rotational speed will be described. For example, the opening degree of the expansion device 4 may be increased at the same time as reducing the current set rotation speed to the corrected rotation speed. Further, the opening degree of the expansion device 4 may be increased immediately after the current set rotation speed is reduced to the corrected rotation speed without being limited to the same at the same time. Further, the opening degree of the expansion device 4 may be increased immediately before the current set rotation speed is reduced to the corrected rotation speed.

[Modification of refrigerant circuit]
FIG. 6 is a modification of the refrigerant circuit shown in FIG. Note that, here, the description will be made focusing on the differences from the present embodiment, and the same reference numerals will be given to the common components.

  The configuration of the refrigerant circuit is not limited to the embodiment shown in FIG. 1, but may be the embodiment shown in FIG. The air conditioner 500 according to the modification shown in FIG. 6 is, for example, a multi-air conditioner for buildings. The air conditioner 500 includes an outdoor unit 501 and an indoor unit 502. The air conditioner 500 is provided with a plurality of indoor units 502. Also, unlike the outdoor unit 101, the outdoor unit 501 is not provided with the aperture device 4. Instead, a throttle device 4 is provided in each indoor unit 502. It should be noted that the squeezing device 4 may be provided in each indoor unit 502, and the squeezing device may be provided in the outdoor unit 101. In the refrigerant circuit CC of the air conditioner 500, an outdoor unit 501 and a plurality of indoor units 502 are connected via a refrigerant pipe P1 and a refrigerant pipe P2. Even with the air conditioner 500 of the embodiment shown in FIG. 6, the same effects as those of the air conditioner 500 according to the present embodiment can be obtained.

  DESCRIPTION OF SYMBOLS 1 Compressor, 2 four-way valve, 3rd heat exchanger, 3A 2nd blower, 4 expansion device, 5th heat exchanger, 5A 1st blower, 50 control device, 50A judgment part, 50B rotation Number correction unit, 50C Target temperature calculation unit, 50D output control device, 50E storage unit, 100 air conditioner, 101 outdoor unit, 102 indoor unit, 500 air conditioner, 501 outdoor unit, 502 indoor unit, C refrigerant circuit, CC Refrigerant circuit, D1 condensation temperature detection section, D2 indoor temperature detection section, P1 refrigerant pipe, P2 refrigerant pipe, RC input device, RC1 air volume setting section, RC2 indoor temperature setting section, RC3 operation mode setting section, SE1 first condensation temperature Sensor, SE2 Indoor temperature sensor, SE3 Second condensation temperature sensor, Va valve.

Claims (5)

A first heat exchanger functioning as a condenser;
A blower for supplying air to the first heat exchanger;
A condensation temperature sensor for detecting a condensation temperature of the first heat exchanger;
An air volume setting unit for receiving the set air volume;
A control device for controlling the blower based on the condensation temperature detected by the condensation temperature sensor and the set air volume sent from the air volume setting unit,
With
The control device includes:
If the condensing temperature is lower than the first temperature during the heating operation, the blower is operated with the current set rotation speed of the blower,
When the condensation temperature becomes a predetermined temperature or higher when running the heating operation, the current setting rotational speed of the blower, is determined according to the size of the condensing temperature, the It is configured to decrease to a corrected rotational speed smaller than the current set rotational speed ,
When the condensing temperature is equal to or higher than the first temperature and lower than a second temperature higher than the first temperature when the heating operation is performed, the condensing temperature corresponds to the corrected rotational speed, Operating the blower at a first rotation speed lower than the current set rotation speed,
The first rotation speed when the set airflow is a second set airflow smaller than the first set airflow is smaller than the first rotation speed when the set airflow is the first set airflow. Is smaller,
When the condensing temperature is higher than the second temperature and lower than a third temperature higher than the second temperature when the heating operation is being performed, the condensing temperature corresponds to the corrected rotational speed, Operating the blower at a second rotation speed lower than the first rotation speed,
An air conditioner wherein the second rotation speed when the set airflow is the second set airflow is smaller than the second rotation speed when the set airflow is the first set airflow. Indoor unit. The corrected rotational speed includes:
The indoor unit of the air-conditioning apparatus according to claim 1 , wherein a rotation speed lower than a rotation speed corresponding to a minimum air flow amount among the plurality of set air flow amounts is included. An indoor unit of the air conditioner according to claim 1 or 2 ,
A throttle device connected to the first heat exchanger and configured to decompress a refrigerant flowing out of the first heat exchanger;
With
The control device includes:
An air conditioner configured to increase the opening degree of the expansion device when the current set rotation speed is reduced to the corrected rotation speed. The control device includes:
The air conditioner according to claim 3 , wherein the opening degree of the expansion device is increased at a timing at which the current set rotation speed is reduced to the corrected rotation speed. A compressor,
A second heat exchanger that functions as an evaporator when performing the heating operation;
Further comprising
A plurality of the indoor units are provided,
The air conditioner according to claim 3 or 4 , wherein the throttle device is connected to each indoor unit.

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