阅读说明：本技术 空调机及控制方法 (Air conditioner and control method ) 是由 伊内启 三浦贤 今任尚希 永井宏幸 于 2018-09-20 设计创作，主要内容包括：本发明实施方式的空调机具有一个或多个室内机、一个或多个室外机、热断开检测部和控制部。一个或多个室内机具有室内膨胀阀和室内送风机。一个或多个室外机具有压缩机。热断开检测部检测在制热运行时的一个或多个所述室内机的热断开。当在一个或多个所述室内机中存在没有进行制热运行的室内机时,控制部基于所述热断开的检测结果来控制所述压缩机的动作和一个或多个所述室内机的室内膨胀阀或室内送风机的动作。(An air conditioner according to an embodiment of the present invention includes one or more indoor units, one or more outdoor units, a thermal disconnection detection unit, and a control unit. One or more indoor units have an indoor expansion valve and an indoor blower. One or more outdoor units have compressors. The thermal disconnection detecting unit detects thermal disconnection of one or more indoor units during heating operation. When there is an indoor unit that does not perform a heating operation among the one or more indoor units, the control unit controls the operation of the compressor and the operation of an indoor expansion valve or an indoor blower of the one or more indoor units based on a result of detection of the thermal disconnection.)

1. An air conditioner, characterized by comprising:

one or more indoor units having an indoor expansion valve and an indoor blower;

one or more outdoor units having a compressor;

a thermal disconnection detecting unit that detects thermal disconnection of one or more indoor units during heating operation; and

and a control unit that controls an operation of the compressor and an operation of an indoor expansion valve or an indoor blower of one or more of the indoor units, based on a result of detection of the thermal cut-off, when there is an indoor unit that does not perform a heating operation among the one or more indoor units.

2. The air conditioner according to claim 1,

the control unit causes an indoor blower of the indoor unit in a thermally disconnected state to perform an intermittent blowing operation.

3. An air conditioner according to claim 2,

the control unit closes an indoor expansion valve of the indoor unit that is thermally disconnected before the intermittent air blowing operation is performed.

4. An air conditioner according to any one of claims 1 to 3,

when an indoor unit in a thermally disconnected state and an indoor unit in a non-thermally disconnected state are mixed in the indoor units other than the indoor unit that is not performing the heating operation, the control unit slightly opens the indoor expansion valve of the indoor unit in the thermally disconnected state.

5. An air conditioner according to any one of claims 1 to 4,

the control unit stops the operation of the compressor when all of the indoor units other than the indoor unit that is not performing the heating operation are in a heat-off state.

6. An air conditioner according to any one of claims 1 to 5,

the control unit causes an indoor blower of an indoor unit to perform a blowing operation when the indoor unit that is not performing the heating operation is permitted to perform the blowing operation in advance.

7. The air conditioner according to claim 6,

the control unit stops closing an indoor expansion valve of an indoor unit that is not performing the heating operation before the indoor unit performs an air blowing operation.

8. An air conditioner according to any one of claims 1 to 7,

the control unit stops an indoor blower of an indoor unit that is not performing the heating operation, without allowing the indoor unit to perform the blowing operation in advance.

9. An air conditioner according to claim 8,

the control unit slightly opens an indoor expansion valve of an indoor unit that is not performing the heating operation, before stopping an indoor blower of the indoor unit.

10. An air conditioner according to any one of claims 1 to 9,

the indoor unit that does not perform the heating operation is an indoor unit that is set to perform a cooling operation or an air supply operation when the air conditioner performs the heating operation.

11. A control method is a control method of an air conditioner including: one or more indoor units having an indoor expansion valve and an indoor blower; and one or more outdoor units having a compressor, the control method comprising:

detecting a thermal disconnection of one or more indoor units during a heating operation; and

and controlling an operation of the compressor and an operation of an indoor expansion valve or an indoor blower of one or more of the indoor units based on a result of the detection of the thermal cut-off when there is an indoor unit that does not perform a heating operation among the one or more indoor units.

Technical Field

Embodiments of the present invention relate to an air conditioner and a control method.

Background

Among air conditioners, there is a multi-type air conditioner in which a plurality of indoor units are connected to one outdoor unit. In the multi-type air conditioner, a plurality of indoor units are distributed in a plurality of spaces, so that air conditioning can be performed in a plurality of spaces in a unified manner. In such a multi-type air conditioner, some of the indoor units are not in a heating operation (hereinafter, referred to as "non-heating state") as a whole during the heating operation, and a small amount of the heating agent may circulate in the indoor units in the non-heating state. Conventionally, when the indoor fan is driven in such a case, the refrigerant is discharged by warm air and condensed by heat exchange, and the amount of the required gas refrigerant may be insufficient.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 3778117

Disclosure of Invention

Technical problem to be solved by the invention

The present invention provides an air conditioner and a control method capable of suppressing the blow-out of warm air from an indoor unit that is not performing a heating operation in a multi-type air conditioner that is performing a heating operation.

Technical scheme for solving technical problem

An embodiment of an air conditioner includes one or more indoor units, one or more outdoor units, a thermal disconnection detecting unit, and a control unit. One or more indoor units have an indoor expansion valve and an indoor blower. One or more outdoor units have compressors. The thermal disconnection detecting unit detects thermal disconnection of the one or more indoor units during heating operation. When there is an indoor unit that does not perform a heating operation among the one or more indoor units, the control unit controls the operation of the compressor and the operation of an indoor expansion valve or an indoor blower of the one or more indoor units based on a result of detection of the thermal disconnection.

Drawings

Fig. 1 is a diagram showing an example of a configuration of a multi-type air conditioner 100 according to an embodiment.

Fig. 2 is a diagram showing a specific example of the functional configuration of the control unit 3 in the embodiment.

Fig. 3 is a flowchart showing a specific example of a process in which the control unit 3 controls the intermittent operation of the indoor fan 13 in the multi-split air conditioner 100 according to the embodiment.

Fig. 4 is a flowchart showing a specific example of a process in which the control unit 3 controls the intermittent operation of the indoor fan 13 in the multi-split air conditioner 100 according to the embodiment.

Fig. 5 is a flowchart showing a specific example of a process in which the control unit 3 controls the intermittent operation of the indoor fan 13 in the multi-split air conditioner 100 according to the embodiment.

Detailed Description

Hereinafter, an air conditioner and a control method according to an embodiment will be described with reference to the drawings.

Fig. 1 is a diagram showing an example of a configuration of a multi-type air conditioner 100 according to an embodiment. As shown in fig. 1, the multi-type air conditioner 100 according to the embodiment includes, for example, 4 indoor units, i.e., a first indoor unit 1A, a second indoor unit 1B, and a third indoor unit 1C, an outdoor unit 2, and a controller 3. The first indoor unit 1A, the second indoor unit 1B, and the third indoor unit 1C are connected to the outdoor unit 2 by connecting pipes.

In the present embodiment, the configuration of the first indoor unit 1A, the configuration of the second indoor unit 1B, and the configuration of the third indoor unit 1C are the same. Therefore, the configuration of the three indoor units 1 will be described by taking the first indoor unit 1A as an example, and the description of the second indoor unit 1B and the third indoor unit 1C will be omitted.

In addition, each configuration of the first indoor unit 1A is identified below by adding a character "a" to a common reference numeral. Similarly, the respective configurations of the second indoor unit 1B are identified by assigning a character "B" to a common reference numeral, and the respective configurations of the third indoor unit 1C are identified by assigning a character "C" to a common reference numeral. In the following, when the first indoor unit 1A, the second indoor unit 1B, and the third indoor unit 1C are not particularly distinguished from each other, common components are denoted by common reference numerals without addition of characters "a", "B", and "C".

The first indoor unit 1A includes an indoor heat exchanger 11A, an indoor expansion valve 12A, an indoor fan 13A, and a room temperature measuring instrument 14A. The indoor heat exchanger 11A is a device that realizes heat exchange between the refrigerant and the indoor air. The indoor heat exchanger 11A is connected to an indoor expansion valve 12A via an indoor pipe. For example, the indoor heat exchanger 11A is a fin-and-tube heat exchanger.

The indoor expansion valve 12A is a device that expands the refrigerant. For example, the indoor expansion Valve 12A is an electronic expansion Valve (PMV) having a variable opening degree. For example, the refrigerant is more likely to flow through the indoor expansion valve 12A as the opening degree of the indoor expansion valve 12A is increased, and the refrigerant is more difficult to flow through the indoor expansion valve 12A as the opening degree of the indoor expansion valve 12A is decreased.

The indoor fan 13A is a fan for promoting heat exchange by the indoor heat exchanger 11A. For example, the indoor air-sending device 13A has a centrifugal fan. The fan of the indoor blower 13A is disposed so as to face the indoor heat exchanger 11A.

The room temperature measuring instrument 14A is a device for measuring the room temperature near the indoor heat exchanger 11A. The room temperature measuring instrument 14A is communicably connected to the control unit 3, and transmits measurement data to the control unit 3.

The outdoor unit 2 includes an outdoor heat exchanger 21, a four-way valve 22, a compressor 23, an outdoor expansion valve 24, an outdoor blower 25, a discharge pressure sensor 26, and a suction pressure sensor 27. The outdoor heat exchanger 21 is a device that realizes heat exchange between the refrigerant and outdoor air. The outdoor heat exchanger 21 is connected to a four-way valve 22 and an outdoor expansion valve 24 by outdoor piping. For example, the outdoor heat exchanger 21 is a fin-and-tube type heat exchanger.

The four-way valve 22 is a device for switching a refrigerant circulation path in the multi-type air conditioner 100. Specifically, the four-way valve 22 switches the circulation path of the refrigerant to either a path for heating operation or a path for cooling operation or defrosting operation. For example, fig. 1 shows a state in which the refrigerant circulation path is switched to the path for the heating operation by the four-way valve 22. The four-way valve 22 is connected to the indoor heat exchanger 11, the compressor 23, and the outdoor heat exchanger 21 by outdoor piping.

The compressor 23 is a device that compresses the refrigerant supplied from the first indoor unit 1A, the second indoor unit 1B, or the third indoor unit 1C. The compressor 23 compresses the refrigerant sucked from the suction port SP and discharges the compressed refrigerant from the discharge port DP. The refrigerant compressed by the compressor 23 is sent to the indoor heat exchanger 11 or the outdoor heat exchanger 21 through the four-way valve 22. An accumulator 231 for storing a liquid refrigerant is attached to the suction port SP of the compressor 23.

The outdoor expansion valve 24 is a device that expands the refrigerant. For example, the outdoor expansion valve 24 may be an electronic expansion valve (PMV) that is the same as the indoor expansion valve 12A. The outdoor expansion valve 24 is connected to the outdoor heat exchanger 21 and the indoor expansion valve 12 by outdoor pipes.

The outdoor fan 25 is a fan for promoting heat exchange by the outdoor heat exchanger 21. For example, the outdoor fan 25 has a centrifugal fan similar to the indoor fan 13, and is disposed so as to face the outdoor heat exchanger 21.

The discharge pressure sensor 26 is a device that measures the pressure of the refrigerant discharged from the compressor 23 (hereinafter referred to as "discharge pressure"). Specifically, the discharge pressure sensor 26 measures the discharge pressure of the refrigerant at the discharge port DP of the compressor 23. The discharge pressure sensor 26 is communicably connected to the control unit 3, and transmits measurement data to the control unit 3.

The suction pressure sensor 27 is a device that measures the pressure of the refrigerant sucked into the compressor 23 (hereinafter referred to as "suction pressure"). Specifically, the suction pressure sensor 27 measures the suction pressure of the refrigerant at the suction port SP of the compressor 23. The suction pressure sensor 27 is communicably connected to the control unit 3, and transmits measurement data to the control unit 3.

The control unit 3 has a function of controlling the operations of the first indoor unit 1A, the second indoor unit 1B, the third indoor unit 1C, and the outdoor unit 2. For example, the control Unit 3 includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, and the like connected by a bus, and executes programs. The control unit 3 functions as a functional unit including a first control unit 31, a thermal disconnection detection unit 32, and a second control unit 33, which will be described later, by executing a program, and controls the operations of the first indoor unit 1A, the second indoor unit 1B, the third indoor unit 1C, and the outdoor unit 2 by communication via the bus.

All or part of the functions of the control unit 3 may be implemented by hardware such as an ASIC (Application Specific Integrated Circuit), a PLD (programmable Logic Device), or an FPGA (Field programmable Gate array). The program may be stored in a computer-readable storage medium. The computer-readable storage medium is a storage device such as a removable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a hard disk incorporated in a computer system. The program may also be transmitted via a telecommunication line.

Fig. 2 is a diagram showing a specific example of the functional configuration of the control unit 3 in the embodiment. The control unit 3 includes a first control unit 31, a thermal disconnection detecting unit 32, and a second control unit 33. The first control unit 31 has a function of controlling the normal air conditioning operation of the first indoor unit 1A, the second indoor unit 1B, the third indoor unit 1C, and the outdoor unit 2 (hereinafter referred to as "normal control function"). The normal air-conditioning operation referred to herein is an operation such as heating, cooling, blowing, or defrosting provided in a conventional air conditioner, and the normal control function includes a function of stopping the indoor unit 1 whose room temperature reaches a set temperature during heating operation. In general, a case where the indoor unit 1 whose room temperature reaches the set temperature during the heating operation is stopped or the indoor unit 1 whose room temperature reaches the set temperature during the heating operation is stopped is referred to as "thermal cutoff".

The thermal disconnection detecting unit 32 has the following functions: the thermal disconnection of the first indoor unit 1A, the second indoor unit 1B, and the third indoor unit 1C is detected based on the discharge pressure of the compressor 23 measured by the discharge pressure sensor 26 and the suction pressure of the compressor 23 measured by the suction pressure sensor 27. The thermal disconnection detecting unit 32 notifies the first control unit 31 and the second control unit 33 of the detection result. The thermal disconnection may be detected when the room temperature measured by the room temperature measuring device 14 reaches a set temperature.

The second control unit 33 has the following functions: the air blowing operation of the indoor unit 1 in the multi-type air conditioner 100 that performs the heating operation as a whole is controlled. Specifically, the second control unit 33 controls the operations of the indoor expansion valve 12, the indoor fan 13, and the compressor 23 of each indoor unit 1 based on the detection result of the thermal disconnection of each indoor unit 1.

Fig. 3, 4, and 5 are flowcharts showing a specific example of the process of controlling the intermittent operation of the indoor fan 13 by the control unit 3 in the multi-split air conditioner 100 according to the embodiment. First, assume the following case: the first control unit 31 starts the heating operation of the first indoor unit 1A, the second indoor unit 1B, the third indoor unit 1C, and the outdoor unit 2 (step S101), and then sets the air supply operation of any one of the indoor units 1. Here, it is assumed that the blowing operation is set for the third indoor unit 1C (step S102). Further, even when the cooling operation is set in step S102, the indoor fan performs the air blowing operation.

In this case, the second control portion 33 determines whether or not the third indoor unit 1C is permitted to perform the blowing operation during the heating operation (step S103). Here, when the third indoor unit 1C is not permitted to perform the air blowing operation during the heating operation (no at step S103), the second control portion 33 slightly opens the indoor expansion valve 12C of the third indoor unit 1C (slightly open at step S104), and stops the indoor blower 13C (off at step S105). On the other hand, when the third indoor unit 1C is permitted to perform the air blowing operation during the heating operation (yes in step S103), the second control unit 33 closes the indoor expansion valve 12C of the third indoor unit 1C (step S106: closed) and operates the indoor air blower 13C (step S107: open).

The reason why the indoor expansion valve 12C is closed in step S106 is to suppress the warm air from being blown out of the third indoor unit 1C by the operation of the indoor blower 13C. However, when the warm air is allowed to be blown out during the air blowing operation, the indoor expansion valve 12C may not necessarily be closed.

In addition, whether or not the third indoor unit 1C is allowed to perform the air blowing operation during the heating operation may be determined by any method. For example, the second control portion 33 may store information indicating whether the air blowing operation is permitted or not permitted for the third indoor unit 1C in advance, and determine whether the air blowing operation is permitted by referring to the information.

Next, the thermal disconnection detecting unit 32 determines whether or not the first indoor unit 1A is in a thermal disconnection state (step S108). Specifically, the thermal cut-off detecting portion 32 determines whether there is a thermal cut-off based on the suction pressure and the discharge pressure of the compressor 23. When determining that the first indoor unit 1A is in the heat-off state (yes at step S108), the heat-off detection unit 32 determines whether or not the second indoor unit 1B is in the heat-off state (step S109).

Here, when determining that the second indoor unit 1B is in the thermally disconnected state (yes in step S109), the second control unit 33 stops the compressor 23 (step S110: off), closes the indoor expansion valve 12A (step S111), and then causes the indoor blower 13A to perform an intermittent blowing operation (step S112: intermittent operation). Subsequently, the second control unit 33 causes the indoor fan 13B to intermittently perform a blowing operation after closing the indoor expansion valve 12B (step S113) (step S114: intermittent operation).

For example, in the intermittent operation, the operation of operating the indoor fan 13 at 300rpm for 1 minute and then stopping it for 1 minute is repeated.

Through the processing up to this point, when the first indoor unit 1A and the second indoor unit 1B are in the thermally disconnected state, the compressor 23 is stopped, and after the indoor expansion valves 12A and 12B are closed, the intermittent operation of the indoor blowers 13A and 13B is performed. Through such processing, it is possible to suppress the warm air from being blown out from the first indoor unit 1A and the second indoor unit 1B in the non-heating state.

On the other hand, when determining in step S109 that the second indoor unit 1B is not in the thermally disconnected state (no in step S109), the second control unit 33 operates the compressor 23 (step S115: on), and after slightly opening the indoor expansion valve 12B (step S116: slight on), causes the indoor blower 13A to perform an intermittent blowing operation (step S117: intermittent operation). Next, the first control unit 31 controls the indoor expansion valve 12B and the indoor blower 13B by the normal control function (steps S118 and S119).

By the processing up to this point, when the first indoor unit 1A is in the thermally disconnected state and the second indoor unit 1B is not in the thermally disconnected state, the intermittent operation of the indoor blower 13A is performed in a state where the indoor expansion valve 12A is slightly (e.g., 30 pulses) opened without stopping the compressor 23. In this case, the second indoor unit 1B is controlled in the same manner as in the normal state. Through such processing, the blowing of warm air from the first indoor unit 1A in the non-heating state can be suppressed.

On the other hand, if it is determined in step S108 that the first indoor unit 1A is not in the thermally disconnected state (no in step S108), the first control unit 31 controls the indoor expansion valve 12A and the indoor fan 13A by the normal control function after the second control unit 33 operates the compressor 23 (step S120) (steps S121 and S122).

Next, the thermal disconnection detecting unit 32 determines whether or not the second indoor unit 1B is in the thermal disconnection state (step S123). Here, when determining that the second indoor unit 1B is in the thermally disconnected state (yes at step S123), the second control unit 33 causes the indoor fan 13B to perform the intermittent blowing operation (S125: intermittent operation) after slightly opening the indoor expansion valve 12B (slightly opening at step S124).

Through the processing described above, when the first indoor unit 1A is not in the heat-off state and the second indoor unit 1B is in the heat-off state, the first indoor unit 1A is controlled in the same manner as in the normal state without stopping the compressor 23. In this case, the indoor blower 13B is intermittently operated with the indoor expansion valve 12B slightly (e.g., 30 pulses) open. Through such processing, the blowing of warm air from the second indoor unit 1B in the non-heating state can be suppressed.

On the other hand, if it is determined in step S123 that the second indoor unit 1B is not in the heat-off state (no in step S123), the first control unit 31 controls the indoor expansion valve 12B and the indoor fan 13B by the normal control function (steps S126 and S127).

Through the processing described above, when the first indoor unit 1A and the second indoor unit 1B are not in the heat-off state, the first indoor unit 1A and the second indoor unit 1B are controlled in the same manner as in the normal state without stopping the compressor 23.

Finally, the second control unit 33 determines whether or not all the indoor units 1 are in the non-heating state (step S128), returns the process to step S103 if it is determined that any of the indoor units 1 is not in the non-heating state (no at step S128), and ends the process if it is determined that all the indoor units 1 are in the non-heating state.

The multi-type air conditioner 100 of the embodiment configured as described above can suppress the warm air from being blown out from the indoor unit 1 in the non-heating state during the heating operation by intermittently operating the indoor fan 13 in accordance with the heat-off state of the indoor unit 1.

In general, a multi-type air conditioner is provided with a plurality of indoor units distributed in a plurality of spaces, and can perform air conditioning of the plurality of spaces in a unified manner. In such a multi-type air conditioner, all the indoor units connected to the multi-type air conditioner are not always operated. For example, some indoor units may stop operating due to user operation or may temporarily stop operating due to thermal disconnection. In this case, it is not necessary to circulate the refrigerant through the indoor unit in the non-heating state or the heat-off state. However, in a non-heating state or a heat-off state during heating operation, a small amount of refrigerant may be circulated in the indoor unit in order to suppress the occurrence of a failure due to liquid accumulation.

On the other hand, air conditioners are generally provided with a room temperature sensor. Therefore, in general, an air conditioner can control a space to be air-conditioned to a comfortable temperature by controlling each component provided based on a room temperature. When the indoor temperature is to be measured for the purpose of such control, in order to avoid the room temperature sensor of the indoor unit in the thermally disconnected state from being affected by the temperature of the indoor heat exchanger, the room temperature may be detected by taking the indoor air to the indoor unit. Therefore, even in the indoor unit in the thermally disconnected state, the indoor blower is often driven at the time of room temperature measurement.

In such a multi-type air conditioner, the indoor fans may be driven simultaneously by a plurality of indoor units in a thermally disconnected state. In this case, a slight amount of refrigerant may circulate through the plurality of indoor units in the thermally disconnected state for the above-described reasons, and in this case, the refrigerant may condense when the indoor fan is driven. When the above-described problems occur simultaneously in a plurality of indoor units, the amount of condensation of the refrigerant increases when the number of rotations of the indoor fan is large and the air volume is large, or when the refrigerant flows in a large amount, and the like, and a rapid pressure drop, a shortage of the refrigerant, and the like are likely to occur.

In such a multi-type air conditioner, when one indoor unit performs a heating operation, a cooling operation or a blowing operation may be set in another indoor unit. In this case, since the flows of the refrigerant are different between the cooling operation and the heating operation, even if such setting is made, the cooling operation and the heating operation cannot be performed at the same time.

Thus, in the multi-type air conditioner, when the heating operation is performed as a whole, the cooling operation or the air blowing operation may be set in the indoor units that do not perform the heating operation, and in such a case, a small amount of refrigerant may be circulated to these indoor units. In such a case, when the indoor fan is driven in the indoor units, the amount of refrigerant condensed in the indoor units increases, and a shortage of refrigerant may easily occur.

According to at least one embodiment described above, the present invention includes: a detection unit that detects a thermal disconnection of one or more indoor units during a heating operation; and a control unit that, when there is an indoor unit that does not perform a heating operation among the one or more indoor units, controls an operation of the compressor and an operation of an indoor expansion valve or an indoor blower of the one or more indoor units based on a result of detection of the thermal cut-off, thereby making it possible to suppress blowing of warm air from the indoor unit that does not perform a heating operation among the multi-type air conditioner that performs a heating operation.

The number of indoor units 1 included in the multi-type air conditioner 100 is only 1 or more, and does not necessarily need to be 3. The number of the outdoor units 2 included in the multi-type air conditioner 100 is not necessarily 1, as long as 2 or more outdoor units are included.

Several embodiments of the present invention have been described, but these embodiments are presented by way of example only and are not intended to limit the scope of the invention. These embodiments may be implemented in other various forms, and various omissions, substitutions, and changes may be made without departing from the spirit of the invention. The above-described embodiments and modifications thereof are included in the scope and spirit of the present invention, and are also included in the invention described in the claims of the present application and the scope equivalent thereto.