TW201901091A - air conditioner - Google Patents

Abstract

Provided is an air conditioner capable of appropriately cleaning an indoor heat exchanger. The air conditioner (100) comprises: a cooling circuit (Q) that circulates a refrigerant in a cooling cycle through, in order, a compressor (31), a condenser, an outdoor expansion valve (34), and an evaporator; and a control unit that controls at least the compressor (31) and the outdoor expansion valve (34). Either the condenser or the evaporator is an outdoor heat exchanger (32) and the other is at least part of an indoor heat exchanger (12). The control unit sequentially performs freezing of the indoor heat exchanger (12); thawing of the upper section of the indoor heat exchanger (12); and thawing of the lower section of the indoor heat exchanger (12).

Description

air conditioner

The present invention relates to an air conditioner.

As a technology for keeping the indoor heat exchanger of an air conditioner clean, for example, Patent Document 1 describes "equipped with a water-supplying means for allowing water to adhere to the surface of the fin after heating operation" Air conditioner. In addition, the above-mentioned moisture applying means is to cause water to adhere to the fin surface of the indoor heat exchanger by performing a cooling operation after the heating operation. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 4931566

[Problems to be Solved by the Invention]

However, in the technique described in Patent Document 1, if water droplets adhere to the surface of the indoor heat exchanger, depending on the situation, there is a possibility that dirt remains in the lower part of the indoor heat exchanger.

Therefore, the subject of this invention is to provide the air conditioner which can wash | clean an indoor heat exchanger suitably. [Means to solve the problem]

In order to solve the aforementioned problems, the present invention has the following features: that is, the control unit sequentially freezes the indoor heat exchanger, defrosts the upper portion of the indoor heat exchanger, and the indoor heat exchanger. Thaw the lower part.

In addition, the present invention has the following features: a first indoor heat exchanger that is an upper portion of the indoor heat exchanger, and a second indoor heat exchanger that is a lower portion of the indoor heat exchanger, The control unit is connected via a second expansion valve, and the control unit causes the first indoor heat exchanger, which is upstream of the second expansion valve, to function as a condenser, and causes the second expansion valve to function as the second expansion valve. The second indoor heat exchanger on the downstream side functions as an evaporator to freeze the second indoor heat exchanger. [Effect of the invention]

According to the present invention, it is possible to provide an air conditioner capable of properly washing an indoor heat exchanger.

[First Embodiment] <Configuration of Air Conditioner> Fig. 1 is a front view of an indoor unit 10, an outdoor unit 30, and a remote controller 40 included in the air conditioner 100 according to the first embodiment. (2) The air conditioner 100 is a device that performs air conditioning by circulating a refrigerant in a refrigeration cycle (heat pump cycle). The air conditioner 100 includes an indoor unit 10 installed indoors (air-conditioned space), an outdoor unit 30 installed outdoors, and a remote control 40 operated by a user.

As shown in FIG. 1, the indoor unit 10 is provided with a remote control transmitting and receiving unit 11. The remote control transmitting and receiving unit 11 transmits and receives a specific signal between itself and the remote control 40 via infrared communication and the like. For example, the remote control transmitting / receiving unit 11 receives signals such as a start / stop command, a change in a set temperature, a change in an operation mode, and a timer setting from the remote control 40. In addition, the remote control transmitting and receiving unit 11 transmits the detected value of the indoor temperature to the remote control 40.

Although not shown in FIG. 1, the indoor unit 10 and the outdoor unit 30 are connected via a refrigerant pipe and connected via a communication line.

FIG. 2 is a longitudinal sectional view of the indoor unit 10. As shown in FIG. The indoor unit 10 is provided with an indoor heat exchanger 12, a drain pan 13, an indoor fan 14, a frame base 15, and a filter in addition to the remote control transmitting and receiving unit 11 (refer to FIG. 1). 16, 16, and the front panel 17, the left and right wind direction panels 18, and the up and down wind direction panels 19.

The indoor heat exchanger 12 is a heat exchanger that exchanges heat between the refrigerant flowing through the heat transfer tube 12g and the indoor air. The drain pan 13 receives water dripping from the indoor heat exchanger 12 and is disposed at a lower side of the indoor heat exchanger 12. The water dripped onto the drain pan 13 is discharged to the outside through a drain pipe (not shown).

The indoor fan 14 is, for example, a cylindrical cross flow fan, and is driven by an indoor fan motor 14a (see FIG. 4). The frame base 15 is a frame in which devices such as an indoor heat exchanger 12 and an indoor fan 14 are installed.

The filters 16 and 16 are for removing dust from the air introduced through the air suction port h1 and the like, and are provided on the upper side and the front side of the indoor heat exchanger 12. The front panel 17 is a panel provided so as to cover the front screen 16 and is capable of turning toward the front side with the lower end as an axis. In addition, the front panel 17 may be configured not to rotate.

The left and right wind direction plates 18 are plate-like members that adjust the wind direction of the air blown into the room in the left and right directions. The left and right wind direction plates 18 are arranged at the downstream side of the indoor fan 14, and are rotated in the left and right directions by the left and right wind direction plate motors 21 (see FIG. 4). The up-and-down wind direction plate 19 is a plate-shaped member that adjusts the wind direction of the air blown out into the room in the up-down direction. The up-and-down wind direction board 19 is arrange | positioned at the downstream side of the indoor fan 14, and is rotated in the up-down direction by the up-and-down wind direction board motor 22 (refer FIG. 4).

The air sucked in through the air suction port h1 is heat-exchanged with the refrigerant circulating through the heat pipe 12g, and the air after the heat exchange is guided to the blow-out air path h2. The air flowing through the blowout air path h2 is guided to a specific direction by the left and right wind direction plates 18 and the up and down wind direction plates 19, and is further blown out to the room through the air blowing outlet h3.

FIG. 3 is an explanatory diagram showing the refrigerant circuit Q of the air conditioner 100. In addition, the solid line arrows in FIG. 3 represent the flow of the refrigerant during heating operation or during reheating and dehumidification. In addition, the dotted arrows in FIG. 3 represent the flow of the refrigerant during the air-conditioning operation.室内 The indoor unit 10 shown in FIG. 3 is provided with an indoor expansion valve V (second expansion valve) in addition to the aforementioned configuration. The indoor heat exchanger 12 includes a first indoor heat exchanger 12a and a second indoor heat exchanger 12b. The first indoor heat exchanger 12a and the second indoor heat exchanger 12b are connected to each other via an indoor expansion valve V.

As shown in FIG. 3, the first indoor heat exchanger 12a is positioned above the second indoor heat exchanger 12b. That is, the first indoor heat exchanger 12 a is an upper portion of the indoor heat exchanger 12. The second indoor heat exchanger 12 b is a lower portion of the indoor heat exchanger 12.

As shown in FIG. 3, the outdoor unit 30 includes a compressor 31, an outdoor heat exchanger 32, an outdoor fan 33, an outdoor expansion valve 34 (first expansion valve), and a four-way valve 35.

The compressor 31 is a machine that compresses a low-temperature and low-pressure gas refrigerant by driving the compressor motor 31a and discharges the gas refrigerant as a high-temperature and high-pressure gas refrigerant. (2) The outdoor heat exchanger 32 is a heat exchanger that exchanges heat between the refrigerant flowing through the heat transfer pipe (not shown) and the outside air sent from the outdoor fan 33.

The outdoor fan 33 is a fan that sends outside air into the outdoor heat exchanger 32 by being driven by the outdoor fan motor 33a, and is installed near the outdoor heat exchanger 32. The outdoor expansion valve 34 is provided with a function of reducing the pressure of the refrigerant, and is provided at the refrigerant pipe J that connects the outdoor heat exchanger 32 and the second indoor heat exchanger 12b.

The four-way valve 35 is a valve that switches the flow path of the refrigerant in accordance with the operation mode of the air conditioner 100. For example, during air-conditioning operation (refer to the dotted arrow), the refrigerant circuit Q passes through the compressor 31, the outdoor heat exchanger 32 (condenser), the outdoor expansion valve 34, and the second indoor heat exchanger 12b (evaporation) in this order. Device), the indoor expansion valve V in a slightly fully opened state, and the first indoor heat exchanger 12a (evaporator) to circulate the refrigerant in the refrigeration cycle.

During the heating operation (refer to the solid line arrow), the refrigerant circuit Q passes through the compressor 31, the first indoor heat exchanger 12a (condenser), the indoor expansion valve V, and the second fully opened state in order. The indoor heat exchanger 12b (condenser), the outdoor expansion valve 34, and the outdoor heat exchanger 32 (evaporator) circulate the refrigerant in the refrigeration cycle.

At the time of the so-called reheat dehumidification (see the solid line arrows), the refrigerant circuit Q passes through the compressor 31, the first indoor heat exchanger 12a (condenser), the indoor expansion valve V, and the second room in this order. The heat exchanger 12b (evaporator), the outdoor expansion valve 34 in a slightly fully opened state, and the outdoor heat exchanger 32 (evaporator) circulate the refrigerant in the refrigeration cycle. In addition, when reheating and dehumidifying, the indoor expansion valve V system is appropriately contracted.

FIG. 4 is a functional block diagram of the air conditioner 100.室内 The indoor unit 10 shown in FIG. 4 includes an imaging unit 23, an environment detection unit 24, and an indoor control circuit 25 in addition to the aforementioned configuration. The imaging unit 23 is an imaging device for an indoor user, and includes an imaging element such as a CCD sensor (Charge Coupled Device) or a CMOS sensor (Complementary Metal Oxide Semiconductor). Based on the imaging result of the imaging unit 23, the human system existing in the room is detected by the indoor control circuit 25. In addition, a "human detection unit" that detects humans existing in an indoor (air-conditioned space) is configured to include an imaging unit 23 and an indoor control circuit 25.

The environment detection unit 24 has a function of detecting the state of the room and the state of the devices of the indoor unit 10. As shown in FIG. 4, the environment detection unit 24 includes an indoor temperature sensor 24 a, a humidity sensor 24 b, and an indoor heat exchanger temperature sensor 24 c. The indoor temperature sensor 24a is a sensor that detects the indoor temperature, and is installed at a specific position of the indoor unit 10 (for example, the air suction side of the filters 16, 16 shown in FIG. 2).

The humidity sensor 24 b is a sensor that detects the humidity of the indoor air, and is provided at a specific position of the indoor unit 10. The indoor heat exchanger temperature sensor 24c is a sensor that detects the temperature of the indoor heat exchanger 12 (see FIG. 2), and is provided at the indoor heat exchanger 12.检测 The detection values of the indoor temperature sensor 24a, the humidity sensor 24b, and the indoor heat exchanger temperature sensor 24c are output to the indoor control circuit 25.

Although not shown, the indoor control circuit 25 is an electronic circuit including a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), various interfaces, and the like. In addition, the program stored in the ROM is read out and expanded into the RAM, and the CPU executes various processes.

As shown in FIG. 4, the indoor control circuit 25 includes a memory section 25 a and an indoor control section 25 b.记忆 In addition to a specific program, the memory section 25a also stores the imaging results of the imaging section 23, the detection results of the environmental detection section 24, and the data received by the receiving section 11 via the remote control. The indoor control unit 25b performs specific control based on the data stored in the memory unit 25a. The processing performed by the indoor control unit 25b will be described later.

The outdoor unit 30 includes an outdoor temperature sensor 36 and an outdoor control circuit 37 in addition to the aforementioned configuration. The outdoor temperature sensor 36 is a sensor that detects the outdoor temperature (outdoor air temperature), and is installed at a specific place of the outdoor unit 30. In addition, although the illustration is omitted in FIG. 4, the outdoor unit 30 also includes various sensors that detect the suction temperature, discharge temperature, and discharge pressure of the compressor 31 (see FIG. 3). Device. The detection value of each sensor including the outdoor temperature sensor 36 is output to the outdoor control circuit 37.

Although not shown, the outdoor control circuit 37 is an electronic circuit including a CPU, ROM, RAM, various interfaces, and the like, and is configured to be connected to the indoor control circuit 25 via a communication line. As shown in FIG. 4, the outdoor control circuit 37 includes a memory section 37 a and an outdoor control section 37 b.

The memory unit 37a stores, in addition to a specific program, the detection value of each sensor including the outdoor temperature sensor 36, and the like. The outdoor control unit 37b controls the compressor motor 31a, the outdoor fan motor 33a, the outdoor expansion valve 34, and the like based on the data stored in the storage unit 37a. Hereinafter, the indoor control circuit 25 and the outdoor control circuit 37 are collectively referred to as "control section K".

Next, a series of processes for washing the indoor heat exchanger 12 (see FIG. 2) will be described. As described above, filters 16 and 16 are provided on the upper side and the front side (air suction side) of the indoor heat exchanger 12 to collect dust (refer to FIG. 2). However, in addition to fine dust, there is a possibility that the oil content generated by food preparation and the like may pass through the filter 16 and adhere to the indoor heat exchanger 12. Therefore, it is desirable to periodically clean the indoor heat exchanger 12. Therefore, in this embodiment, the indoor heat exchanger 12 is used to freeze the moisture contained in the air in the indoor unit 10, and thereafter, the ice or frost of the indoor heat exchanger 12 is dissolved. Here, the indoor heat exchanger 12 is cleaned. This series of processes is called "cleaning process" of the indoor heat exchanger 12.

FIG. 5 is a flowchart of a cleaning process performed by the control unit K of the air conditioner 100 (refer to FIGS. 3 and 4 as appropriate). In addition, until "START" in FIG. 5, it is assumed that a specific air-conditioning operation (air-conditioning operation, heating operation, etc.) is performed. In addition, it is assumed that the start condition of the cleaning process of the indoor heat exchanger 12 is established at "START". The so-called "starting condition of the washing process" is, for example, a general condition such that the value obtained by accumulating the time of the air-conditioning operation from the end of the previous washing process reaches a specific value.

In step S101, the control unit K stops the air-conditioning operation for a specific time (for example, several minutes). The aforementioned specific time is a time for stabilizing the refrigeration cycle, and is set in advance. For example, when the heating operation performed until "START" is interrupted and the indoor heat exchanger 12 is frozen (S103), the control unit K is configured to cause the refrigerant to flow in a direction opposite to that during the heating operation. To control the four-way valve 35.

In addition, when the air-conditioning operation is interrupted and the indoor heat exchanger 12 is frozen, the processing in step S101 may be omitted. This is because the direction in which the refrigerant flows during the air-conditioning operation (immediately before START) is the same as the direction in which the refrigerant flows during the freezing of the indoor heat exchanger 12 (S103).

Next, in step S102, the control unit K determines whether there is a kitchen in the air-conditioned space. That is, the control unit K determines whether or not the position of the human being is detected in the air-conditioned space based on changes in the position of the human being detected by the aforementioned “human detection unit” (the imaging unit 23 and the indoor control unit 25b: refer to FIG. 4). Is there a kitchen.

If it is specifically described about step S102, first, the control unit K detects a human being present in the air-conditioned space based on the imaging result of the imaging unit 23. After that, the control unit K, when the height of the head of the human detected by the aforementioned “human detection unit” is within a specific range and the human is in the left-right direction or the depth direction (for the indoor unit 10) When a round trip is performed within a certain distance), it is determined that the human is performing food conditioning in the kitchen (that is, a kitchen is present in the air-conditioned space). This is because when humans are preparing food in the kitchen, the humans often go back and forth in the left-right or depth directions while standing.

When there is a kitchen in the air-conditioned space in step S102 (S102: Yes), the processing of the control unit K proceeds to step S103. In this case, there is a high possibility that the oil content accompanying the food preparation in the kitchen will adhere to the indoor heat exchanger 12.

In step S103, the control unit K causes the indoor heat exchanger 12 to freeze. That is, the control unit K freezes the first indoor heat exchanger 12 a and the second indoor heat exchanger 12 b shown in FIG. 3. If step S103 is specifically described, the control unit K makes the first indoor heat exchanger 12a and the second indoor heat exchanger 12b function as evaporators in the same manner as in the air-conditioning operation. In this case, the indoor expansion valve V is slightly opened, and the opening degree of the outdoor expansion valve 34 is appropriately adjusted. As a result, the moisture contained in the air in the indoor unit 10 is frozen by the frost on the first indoor heat exchanger 12a and the second indoor heat exchanger 12b. The details of the processing in step S103 will be described later.

Next, in step S104, the control unit K performs the aforementioned reheating and dehumidification, and thaws the upper portion of the indoor heat exchanger 12. That is, the control unit K causes the first indoor heat exchanger 12a to function as a condenser, and causes the second indoor heat exchanger 12b to function as an evaporator. In this case, the outdoor expansion valve 34 is slightly opened, and the opening degree of the indoor expansion valve V is appropriately adjusted. As a result, the first indoor heat exchanger 12a (the upper part of the indoor heat exchanger 12) is thawed. In addition, the freezing system of the second indoor heat exchanger 12b (the lower portion of the indoor heat exchanger 12) is further advanced.

When the frost adhered to the first indoor heat exchanger 12a is dissolved, a dirty water system including dust, oil, and the like flows down, and the first indoor heat exchanger 12a is flushed. Furthermore, the water flowing from the first indoor heat exchanger 12a is frozen at the second indoor heat exchanger 12b in a frozen state and frozen again. That is, on the outside of the frost of the frozen second indoor heat exchanger 12b, a layer of ice containing dirt and dust, such as dirt, is formed. Therefore, when the second indoor heat exchanger 12b is frozen (S105), the layer of ice containing the dirty ice of the first indoor heat exchanger 12a is dissolved, and the heat is not affected by the second indoor heat exchanger. The exchanger 12b causes pollution to come and go.

FIG. 6 is an explanatory diagram showing the driving states of the compressor 31 and the indoor fan 14 when there is a kitchen in the air-conditioned space (refer to FIG. 3 as appropriate). In addition, the horizontal axis of FIG. 6 is time. The vertical axis in FIG. 6 represents ON / OFF of the compressor 31 and ON / OFF of the indoor fan 14.

In the example shown in FIG. 6, the specific air-conditioning operation is performed until time t1, and the compressor 31 and the indoor fan 14 are being driven (that is, they are in the ON state). Thereafter, at times t1 to t2, the compressor 31 and the indoor fan 14 are stopped (S101 in FIG. 5). Thereafter, at times t2 to t3, the indoor heat exchanger 12 is frozen (S103), and further, at times t3 to t4, the system is reheated and dehumidified (S104).

In addition, even when the indoor fan 14 is stopped at times t2 to t3, the water vapor pressure in the indoor unit 10 becomes low due to the freezing of water vapor at the indoor heat exchanger 12 and the water vapor Due to the diffusion phenomenon (natural convection), water vapor is continuously supplied to the surface of the indoor heat exchanger 12, and the frost system grows.

When the indoor heat exchanger 12 is frozen (S103 in FIG. 5), the refrigerant system flows in the same direction as that during the air-conditioning operation, and during reheating and dehumidification (S104), the refrigerant system faces the same as when the heating operation Flow in the direction. That is, the direction of the refrigerant flow is reversed when the indoor heat exchanger 12 is frozen and reheated and dehumidified. However, in this embodiment, the reheating and dehumidification is started immediately after the freezing of the indoor heat exchanger 12 is completed (the specific stop period is not provided) (see time t3 in FIG. 6). In other words, the control unit K starts thawing of the first indoor heat exchanger 12a immediately after the freezing of the first indoor heat exchanger 12a and the second indoor heat exchanger 12b is completed.

This makes it possible to perform reheating and dehumidification without dissolving the frost attached to the second indoor heat exchanger 12b (time t3 to t4). If the reheating and dehumidification is started after the frost of the second indoor heat exchanger 12b is completely dissolved, it will mix with the dirty water containing dust, oil, etc. attached to the first indoor heat exchanger 12a and When it falls, the surface of the second indoor heat exchanger 12b becomes dirty. Therefore, in this embodiment, between the freezing operation (times t2 to t3) and the reheating dehumidification (times t3 to t4), it is specifically set that no stopping period of each device is provided.

Returning to FIG. 5 again and continuing the description. In step S105, the control unit K defrosts the lower portion of the indoor heat exchanger 12. That is, the control unit K defrosts the second indoor heat exchanger 12b. If it is specifically explained about step S105, the control part K will make the stop state of the apparatus containing the compressor 31, the outdoor fan 33, and the indoor fan 14 shown in FIG. 3 last for a specific time. Accordingly, the ice or frost of the second indoor heat exchanger 12b is naturally dissolved at room temperature. For a more detailed explanation, before this, the layer of ice (including dust, oil, etc. attached to the first indoor heat exchanger 12a) formed at the second indoor heat exchanger 12b by the process of step S104. The dirty layer of ice) was dissolved at room temperature and dripped onto the drain pan 13 (refer to FIG. 2).

On the inner side of the ice layer, as described above, there is frost attached to the second indoor heat exchanger 12b by the process of step S103. That is, the water containing dirt, oil, and the like attached to the first indoor heat exchanger 12a is not directly transmitted to the surface of the fins (not shown) of the second indoor heat exchanger 12b. And flow, but flow to the outside of the frost attached to this fin. Therefore, the second indoor heat exchanger 12b is hardly contaminated by dust, oil, and the like attached to the first indoor heat exchanger 12a.

After that, in the second indoor heat exchanger 12b, the frost on the inner side than the ice layer described above is dissolved and drips onto the drain pan 13 (refer to FIG. 2). As a result, the second indoor heat exchanger 12b is also washed. Thereafter, the water dripped onto the drain pan 13 is discharged to the outside through a drain pipe (not shown).

As such, the control unit K freezes the indoor heat exchanger 12 (S103) and the upper part of the indoor heat exchanger 12 in a sequential manner when there is a kitchen in the air-conditioned space (S102: Yes). Thawing (S104) and thawing of the lower part of the indoor heat exchanger 12 (S105).

Next, in step S106, the control unit K causes the indoor heat exchanger 12 to dry. For example, the control unit K performs the heating operation and the air supply operation in order as the processing of step S106. By the above-mentioned heating operation, since a high-temperature refrigerant flows in the indoor heat exchanger 12, water on the surface of the indoor heat exchanger 12 evaporates. Furthermore, since the inside of the indoor unit 10 is dried by the air supply operation after the heating operation, the effect of preventing bacteria and mold is exhibited. After the processing of step S107 is performed, the control unit K ends a series of washing processes (END).

In the example shown in FIG. 6, after freezing and reheating and dehumidification are sequentially performed at times t2 to t4 (steps S103 and S104 in FIG. 5), at times t4 to t5, the indoor heat exchanger 12 The lower part is thawed (S105). Thereafter, at times t5 to t7, the indoor heat exchanger 12 is dried by sequentially performing heating operation and air supply operation (S106).

When it is determined that there is no kitchen in the air-conditioned space in step S102 of FIG. 5 (S102: No), the processing of the control unit K proceeds to step S107. In this case, the possibility of oil content adhering to the indoor heat exchanger 12 is low. Therefore, the control unit K freezes the indoor heat exchanger 12 in step S107, and then proceeds to the process of step S108 without performing the aforementioned reheating and dehumidification.

In step S108, the control unit K defrosts the indoor heat exchanger 12. That is, the control unit K defrosts both the first indoor heat exchanger 12a and the second indoor heat exchanger 12b. If it is specifically explained about step S108, the control part K will make the stop state of the apparatus containing the compressor 31, the outdoor fan 33, and the indoor fan 14 shown in FIG. 3 last for a specific time. Accordingly, since the frost of the second indoor heat exchanger 12b is naturally dissolved at room temperature, the dust adhering to the indoor heat exchanger 12 is washed away. In addition, when there is no kitchen in the air-conditioned space (S102: No), the dirty system of the indoor heat exchanger 12 is not too serious. Therefore, at the time point when the processing of step S108 is completed, there is almost no possibility that dirt remains under the indoor heat exchanger 12.

After the processing in step S108 is performed, the control unit K causes the indoor heat exchanger 12 to dry in step S106, and ends a series of washing processing (END).

FIG. 7 is a flowchart showing a process for freezing the indoor heat exchanger 12 (S103 in FIG. 5) (refer to FIGS. 3 and 4 as appropriate). In step S103a, the control unit K controls the four-way valve 35. That is, the control unit K controls the four-way valve 35 so that the outdoor heat exchanger 32 functions as a condenser and the indoor heat exchanger 12 functions as an evaporator. In addition, when the air-conditioning operation is performed immediately before the "washing process" (a series of processes shown in Fig. 5) is performed, in this embodiment, the control device is set to step S103a The state of the four-way valve 35 is maintained.

In step S103b, the control unit K sets a freezing time. This "freezing time" is a period of time during which a specific control (S103c to S103e) for freezing the indoor heat exchanger 12 is continued. For example, the higher the detection value of the humidity sensor 24b (refer to FIG. 4) by the control unit K, the shorter the freezing time is set. Accordingly, the indoor heat exchanger 12 can be frosted with an appropriate amount of moisture required for cleaning the indoor heat exchanger 12. In addition, the freezing time of the indoor heat exchanger 12 may be a fixed value.

Next, in step S103c, the control unit K sets the rotation speed of the compressor 31. For example, the higher the detection value of the outdoor temperature sensor 36 (refer to FIG. 4), the control unit K increases the rotation speed of the compressor motor 31 a. This is because in order to extract heat from the indoor air in the indoor heat exchanger 12, it is necessary to sufficiently perform the heat radiation in the outdoor heat exchanger 32 in accordance with this. By setting the rotation speed of the compressor 31 in this way, the heat exchange system at the outdoor heat exchanger 32 is appropriately performed, and the freezing of the indoor heat exchanger 12 is also appropriately performed.

Next, in step S103d, the control unit K adjusts the opening degree of the outdoor expansion valve 34. In addition, in step S103d, it is desirable to make the opening degree of the outdoor expansion valve 34 smaller than that in a normal air-conditioning operation. As a result, the refrigerant at a lower temperature and a lower pressure than during normal air-conditioning operation flows into the indoor heat exchanger 12 through the outdoor expansion valve 34. Therefore, the indoor heat exchanger 12 becomes easy to freeze, and the amount of power consumption required to freeze the indoor heat exchanger 12 can be reduced.

In step S103e, the control unit K determines whether the temperature of the indoor heat exchanger 12 is within a specific range. The aforementioned “specific range” refers to a range in which the moisture contained in the air in the indoor unit 10 can be frozen at the indoor heat exchanger 12 and is set in advance. The temperature of the indoor heat exchanger 12 is detected by the indoor heat exchanger temperature sensor 24c (see FIG. 4).

When the temperature of the indoor heat exchanger 12 is outside the specified range in step S103e (S103e: No), the processing of the control unit K returns to step S103d. For example, when the temperature of the indoor heat exchanger 12 is higher than a specific range, the control unit K decreases the opening degree of the outdoor expansion valve 34 further (S103d). As described above, when the indoor heat exchanger 12 is frozen, the control unit K adjusts the opening degree of the outdoor expansion valve 34 so that the temperature of the indoor heat exchanger 12 falls within a specific range.

In addition, when the indoor heat exchanger 12 is frozen, the control unit K may also set the indoor fan 14 to a stopped state (refer to time t2 to t3 in FIG. 6), and may also set the indoor fan 14 to a specific state. Rotation speed to drive. This is because, regardless of the circumstances, the freezing of the indoor heat exchanger 12 will progress. In the freezing of the indoor heat exchanger 12, the up-and-down wind direction plate 19 (refer to FIG. 2) may be either the open state or the closed state. There will be less discomfort.

When the temperature of the indoor heat exchanger 12 is within a specific range in step S103e of FIG. 7 (S103e: Yes), the processing of the control unit K proceeds to step S103f. In step S103f, the control unit K determines whether or not the freezing time set in step S103b has elapsed. When a specific freeze time has not elapsed from "START" (S103f, No), the processing of the control unit K returns to step S103c. On the other hand, when a specific freezing time has elapsed from "START" (S103f: Yes), the control unit K ends a series of processes for freezing the indoor heat exchanger 12 (END).

In addition, since the processing of step S107 (freezing of the indoor heat exchanger 12) shown in FIG. 5 is the same as the aforementioned step S103 (a series of processing shown in FIG. 7), detailed description is omitted.

<Effects> According to the first embodiment, when there is a kitchen in the air-conditioned space (S102: Yes in FIG. 5), the control unit K is after freezing the indoor heat exchanger 12 (S103) First, the upper part of the indoor heat exchanger 12 is thawed (S104). As a result, the water system containing dirt, oil, and the like adhering to the upper part of the indoor heat exchanger 12 flows down, and freezes at the lower part of the indoor heat exchanger 12 in a frozen state to form a layer of ice. . After that, if the lower part of the indoor heat exchanger 12 is thawed (S105), the frost attached to the lower part of the indoor heat exchanger 12 (the frost existing on the inner side of the ice layer) after the aforementioned ice layer is dissolved Department of dissolution. In this way, by washing the upper and lower portions of the indoor heat exchanger 12 in stages, it becomes difficult for the dirt to remain on the lower portion of the indoor heat exchanger 12. In particular, since the oil system generated due to food preparation and the like becomes difficult to remain in the lower portion of the indoor heat exchanger 12, the indoor heat exchanger 12 can be appropriately cleaned.

When there is no kitchen in the air-conditioned space (S102: No), the entire freezing and thawing of the indoor heat exchanger 12 is sequentially performed (S107, S108). Therefore, since the system does not perform reheat dehumidification (S104), a series of washing processes can be performed in a short time in response to this.

[Second Embodiment] The second embodiment is different from the first embodiment in that an indoor expansion valve is not provided at the indoor unit 10A (refer to FIG. 5). In addition, in the second embodiment, the upper portion of the indoor heat exchanger 12A (see FIG. 8) is thawed by reducing the rotation speed of the compressor 31 (see FIG. 8) as compared with that during normal air-conditioning operation. In this regard, it is different from the first embodiment. The other configurations (the configurations shown in FIGS. 1, 2, and 4, the flowchart shown in FIG. 7, and the like) are the same as those of the first embodiment. Therefore, the description will be made with respect to portions different from those in the first embodiment, and the description of the overlapping portions will be omitted.

FIG. 8 is an explanatory diagram showing the refrigerant circuit QA of the air conditioner 100A according to the second embodiment. The refrigerant circuit QA shown in FIG. 8 is a circuit that circulates the refrigerant in the refrigeration cycle through the compressor 31, the "condenser", the outdoor expansion valve 34 (the first expansion valve), and the "evaporator" in this order. . One of the "condenser" and the "evaporator" is the outdoor heat exchanger 32, and the other is at least a part of the indoor heat exchanger 12A.

When the indoor heat exchanger 12A functions as an evaporator (refer to the dotted arrow in FIG. 8), the upper part of the indoor heat exchanger 12A is positioned further downstream than the lower part of the indoor heat exchanger 12A. Sideways.

FIG. 9 is a flowchart of a washing process performed by the control unit K of the air conditioner 100 (refer to FIG. 8 as appropriate). In addition, the same processes as those in the first embodiment (see FIG. 5) are assigned the same step numbers. After the indoor heat exchanger 12A is frozen in step S103, the processing of the control unit K proceeds to step S104a.

In step S104a, the control unit K sets the rotation speed of the compressor 31 (that is, the rotation speed of the compressor motor 31a shown in FIG. 4) to be smaller than that during normal air-conditioning operation, and sets The upper part of the indoor heat exchanger 12A is thawed. For a more detailed description of the processing of step S104a, the control unit K controls the four-way valve 35 and drives the compressor 31 so that the refrigerant flows in the same direction as during the cooling operation. In this way, during the thawing of the upper portion of the indoor heat exchanger 12A (S104a), the refrigerant is sequentially passed through the compressor 31, the outdoor heat exchanger 32, the outdoor expansion valve 34, the upper portion of the indoor heat exchanger 12A, and the indoor heat exchange. The lower part of the heater 12A is circulated in the refrigerant circuit QA.

As described above, since the rotation speed of the compressor 31 is smaller than that of the ordinary air conditioner, the flow rate of the refrigerant flowing in the indoor heat exchanger 12A becomes smaller than that of the ordinary air conditioner (for example, air-conditioning While running) and smaller. As a result, the refrigerant system completely evaporates in the middle of the flow path of the indoor heat exchanger 12A. Therefore, the freezing system on the upstream side progresses further, and the downstream system is thawed. In other words, at the lower part of the indoor heat exchanger 12A, the freezing system progresses further, and the upper part of the indoor heat exchanger 12A is thawed.

When the frost adhered to the indoor heat exchanger 12A is dissolved, a dirty water system including dust, oil, and the like flows down, and the upper part of the indoor heat exchanger 12A is rinsed. Furthermore, the water flowing down from the upper part of the indoor heat exchanger 12A is frozen at the lower part of the indoor heat exchanger 12A in a frozen state. That is, in the lower part of the indoor heat exchanger 12A, on the outside of the adhered frost, a layer of ice containing dirt, dust, and the like is formed. Therefore, when the lower part of the indoor heat exchanger 12A is frozen later (S105), the layer of the contaminated ice containing the upper part of the indoor heat exchanger 12A is dissolved without affecting the indoor heat exchanger. The lower part of 12A caused pollution to flow.

The processing in steps S105 to S108 is the same as that in the first embodiment (see FIG. 5), and therefore description thereof is omitted.

<Effects> According to the second embodiment, the upper part and lower part of the indoor heat exchanger 12A are washed in stages, so that the dirt is difficult to remain in the lower part of the indoor heat exchanger 12A. In the thawing of the upper portion of the indoor heat exchanger 12A (S104a in FIG. 9), the rotation speed of the compressor 31 is set to a value smaller than that during normal air-conditioning operation. Therefore, compared with the first embodiment, the power consumption of the air conditioner 100A can be further reduced.

Regardless of whether the indoor heat exchanger 12A is frozen (S103 in FIG. 9) and the upper part of the indoor heat exchanger 12A is thawed (S104a), the flow of the refrigerant in the refrigerant circuit QA is the same. It is the same as in air-conditioned operation. Therefore, immediately after the thawing of the upper portion of the indoor heat exchanger 12A is started, there is no sudden change in the temperature of the refrigerant or the direction of the flow of the refrigerant due to the fact that, for example, the indoor heat exchanger 12A Therefore, it is possible to suppress the occurrence of sounds caused by these phenomena.

«Modifications» The foregoing describes the air conditioners 100 and 100A of the present invention based on the embodiments, but the present invention is not limited to these descriptions, and various changes can be made. For example, in the first embodiment, the thawing process of the first indoor heat exchanger 12a is started immediately after the freezing of the first indoor heat exchanger 12a and the second indoor heat exchanger 12b is completed. Explanation (refer to time t3 in FIG. 6), but the system is not limited to this. For example, the control unit K may be configured to restart the defrosting of the first indoor heat exchanger 12a after a certain period of time has elapsed since the freezing of the first indoor heat exchanger 12a and the second indoor heat exchanger 12b has ended. . (Ii) The "specific time" described above is set in advance as a time that does not completely defrost the second indoor heat exchanger 12b. During this "specified time", each machine including the compressor 31 is stopped. As a result, the first indoor heat exchanger 12a can be thawed while the second indoor heat exchanger 12b is maintained in a frozen state. In addition, by setting the "specific time" described above, the flow due to the refrigerant can be changed in the reverse direction (when frozen, it is the same flow as the cooling operation, and when the first indoor heat exchanger 12a is thawed, This is to suppress the occurrence of sound caused by the same flow as heating operation).

In each embodiment, the control unit K is a process for defrosting the lower portion of the indoor heat exchanger 12 by maintaining the stopped state of each device including the compressor 31 for a specific time (S105 in FIG. 5). , To explain, but the system is not limited to this. For example, the system may be configured such that the control unit K causes the indoor heat exchanger 12 to function as a condenser in the same manner as during the heating operation, and the lower portion of the indoor heat exchanger 12 is thawed. In addition, the system may be configured to defrost the lower portion of the indoor heat exchanger 12 by causing the control unit K to perform an air blowing operation.

In each embodiment, the control unit K has been described in order to dry and freeze the indoor heat exchanger 12 by sequentially performing heating operation and air supply operation (t5 to t7 in FIG. 6). However, The system is not limited to this. That is, the control unit K may be configured to dry the indoor heat exchanger 12 by performing heating operation only for a specific time. In addition, the control unit K may be configured to dry the indoor heat exchanger 12 by performing only a blower operation for a specific time.

In each of the embodiments, the control unit K is described based on the imaging result of the imaging unit 23 (refer to FIG. 4) to determine whether there is a kitchen in the air-conditioned space (S102 in FIG. 5). However, the department is not limited to this. For example, the system may be configured to obtain an indoor thermal image by an indoor temperature sensor 24a (human detection unit, see FIG. 4) such as a thermopile or a pyroelectric infrared sensor. In this case, the control unit K detects a change in the position of a human based on the aforementioned thermal image, and determines whether there is a kitchen in the air-conditioned space.

Moreover, in each embodiment, when it is determined that a kitchen exists in the air-conditioned space (S102 in FIG. 5; Yes), the control unit K causes the upper portion and the lower portion of the indoor heat exchanger 12 to be staged. The thawing process (S104, S105) has been described, but the system is not limited to this. For example, the system may be configured such that the upper part and the lower part of the indoor heat exchanger 12 are thawed in stages, regardless of whether a kitchen exists in the air-conditioned space. Thereby, dirt, oil, etc. adhering to the indoor heat exchanger 12 can be appropriately washed away.

In addition, in each embodiment, the process of making the control unit K set the rotation speed of the compressor 31 and appropriately adjusting the opening degree of the outdoor expansion valve 34 when the indoor heat exchanger 12 is frozen (Fig. 7 of S103c, S103d), but the system is not limited to this. For example, when the indoor heat exchanger 12 is frozen, the control unit K may be configured to maintain the outdoor expansion valve 34 at a specific opening degree and bring the temperature of the indoor heat exchanger 12 close to a specific target temperature. Let's adjust the rotation speed of the compressor 31.

In the first embodiment, the entire indoor heat exchanger 12 is sequentially frozen, the first indoor heat exchanger 12a (the upper part of the indoor heat exchanger 12) is thawed, and the second indoor heat exchanger is sequentially The defrosting process of 12b (the lower part of the indoor heat exchanger 12) has been described (refer to FIG. 5), but the system is not limited to this. For example, the system may be reheated and dehumidified to freeze the second indoor heat exchanger 12b. For a more detailed description, in the refrigerant circuit Q (refer to FIG. 3) for circulating the refrigerant in the refrigeration cycle through the compressor 31, the "condenser", the second expansion valve V, and the "evaporator" in this order, The control unit K may be configured to perform reheat dehumidification as described below. That is, the control unit K causes the first indoor heat exchanger 12a on the upstream side of the second expansion valve V to function as a condenser, and causes the second indoor valve on the downstream side of the second expansion valve V to function as a condenser. The indoor heat exchanger 12b functions as an evaporator to freeze the second indoor heat exchanger 12b. Before this, the entire indoor heat exchanger 12 can be frozen (same as S103 in FIG. 5), and even if it is not frozen, the cleaning effect of the indoor heat exchanger 12 can be exerted. Since the dew condensation water generated during the air-conditioning operation flows to the indoor heat exchanger 12b, the lower part of the indoor heat exchanger 12 (the second indoor heat exchanger 12b) is liable to be dirty. As described above, after the second indoor heat exchanger 12b is frozen, the water system generated by the thawing flows together with the dirt attached to the second indoor heat exchanger 12b, so the system can exchange indoor heat. The device 12 is effectively cleaned.

The first embodiment and the second embodiment may be combined. For example, in the configuration of the indoor unit 10 (refer to FIG. 3) of the first embodiment, the indoor expansion valve V (refer to FIG. 3) may be configured to be slightly fully opened and described in the second embodiment. A series of cleaning processes (see Figure 9). In addition, the control unit K can be configured to be independent of one of the aforementioned series of cleaning processes, and to perform reheat dehumidification in accordance with the operation of the remote control 40 (refer to FIG. 1) by the user.

In each embodiment, the indoor unit 10 and the outdoor unit 30 have been described as having a configuration in which one unit is installed, but the system is not limited to this. That is, a plurality of indoor units connected in parallel may be installed, and a plurality of outdoor units connected in parallel may also be installed.

It should be noted that the embodiments are described in detail for easy understanding of the present invention, and the present invention is not limited to those that include all the components described above. In addition, it is possible to add, delete, and replace other configurations with respect to a part of the configuration of the embodiment. In addition, the aforementioned institutions or structures are representatives who are considered to be needed in the description, and not necessarily all the institutions or structures on the product.

100, 100A‧‧‧ Air Conditioner

10, 10A‧‧‧ indoor unit

12, 12A‧‧‧ Indoor heat exchanger (evaporator, condenser)

12a‧‧‧The first indoor heat exchanger (upper part of the indoor heat exchanger)

12b‧‧‧ 2nd indoor heat exchanger (lower part of indoor heat exchanger)

14‧‧‧ indoor fan

18‧‧‧ around wind vane

19‧‧‧ Up and down wind board

23‧‧‧ Camera Department (Human Detection Department)

30‧‧‧ outdoor unit

31‧‧‧compressor

31a‧‧‧compressor motor (compressor motor)

32‧‧‧Outdoor heat exchanger (condenser / evaporator)

33‧‧‧outdoor fan

34‧‧‧Outdoor expansion valve (first expansion valve)

35‧‧‧Four Direction Valve

40‧‧‧Remote control

K‧‧‧Control Department

Q, QA‧‧‧Refrigerant circuit

V‧‧‧Indoor expansion valve (second expansion valve)

[FIG. 1] It is a front view of an indoor unit, an outdoor unit, and a remote controller provided in the air conditioner according to the first embodiment of the present invention. [Fig. 2] is a longitudinal sectional view of an indoor unit provided in the air conditioner according to the first embodiment of the present invention. [Fig. 3] It is an explanatory diagram showing a refrigerant circuit of the air conditioner according to the first embodiment of the present invention. [Fig. 4] is a functional block diagram of the air conditioner according to the first embodiment of the present invention. [Fig. 5] Fig. 5 is a flowchart of a washing process performed by the control unit of the air conditioner according to the first embodiment of the present invention. [Fig. 6] It is an explanatory diagram showing the driving states of the compressor and the indoor fan when the kitchen is present in the air-conditioned space in the air conditioner according to the first embodiment of the present invention. [FIG. 7] A flowchart showing a process for freezing an indoor heat exchanger in the air conditioner according to the first embodiment of the present invention. [Fig. 8] It is an explanatory diagram showing a refrigerant circuit of an air conditioner according to a second embodiment of the present invention. [Fig. 9] This is a flowchart of a cleaning process performed by a control unit of an air conditioner according to a second embodiment of the present invention.

Claims (7)

An air conditioner comprising: a refrigerant circuit that circulates a refrigerant in a refrigeration cycle through a compressor, a condenser, a first expansion valve, and an evaporator in order; and a control unit that is at least as described above. The compressor and the first expansion valve are controlled. 一方 One of the condenser and the evaporator is an outdoor heat exchanger, and the other is at least a part of an indoor heat exchanger. The control unit is implemented in sequence. A process of freezing the indoor heat exchanger, thawing the upper part of the indoor heat exchanger, and thawing the lower part of the indoor heat exchanger is performed. The air conditioner according to item 1 of the scope of the patent application, wherein: is provided with a human detection section that detects a human being present in the air-conditioned space; the control section, when the human When the height of the head is within a specific range, and the human is reciprocating in the left-right direction or the depth direction for the indoor unit, the aforementioned processing is performed. The air conditioner according to item 1 or 2 of the scope of the patent application, wherein the first indoor heat exchanger that is an upper part of the indoor heat exchanger and the second indoor heat exchanger that is a lower part of the indoor heat exchanger The heat exchanger is connected via a second expansion valve. The control unit, as the processing, sequentially freezes the first indoor heat exchanger and the second indoor heat exchanger, and the first indoor heat. Thawing of the exchanger and thawing of the aforementioned second indoor heat exchanger. The air conditioner according to item 3 of the scope of patent application, wherein: the control unit starts the first indoor heat exchanger immediately after the freezing of the first indoor heat exchanger and the second indoor heat exchanger is completed Thaw. The air conditioner according to item 3 of the scope of patent application, wherein: the control unit starts the above after a specific time has elapsed since the freezing of the first indoor heat exchanger and the second indoor heat exchanger has ended. Thawing of the first indoor heat exchanger. The air conditioner according to item 1 of the scope of the patent application, wherein: The control unit sets the rotation speed of the compressor's motor at a time when the rotation speed of the compressor is higher than that of a normal air conditioner during thawing of the upper portion of the indoor heat exchanger. Further, the refrigerant is circulated in the refrigerant circuit through the compressor, the outdoor heat exchanger, the first expansion valve, the upper part of the indoor heat exchanger, and the lower part of the indoor heat exchanger in this order. An air conditioner comprising: a refrigerant circuit that circulates a refrigerant through a refrigeration cycle through a compressor, a condenser, a second expansion valve, and an evaporator in order; and a control unit that The compressor and the second expansion valve are controlled by a first indoor heat exchanger that is an upper part of the indoor heat exchanger and a second indoor heat exchanger that is a lower part of the indoor heat exchanger. 2 expansion valves are connected, the control unit is to make the first indoor heat exchanger, which is upstream of the second expansion valve, function as the condenser, and make it the second expansion valve. The second indoor heat exchanger on the downstream side functions as the evaporator, and freezes the second indoor heat exchanger.