MULTI-TYPE AIR-CONDITIONING DEVICE

Abstract

 A multi-type air-conditioning device is capable of simultaneously performing cooling and heating operations and includes an outdoor unit, a plurality of indoor units having indoor heat exchangers and leakage detection sensors, an SP device, and an MP device. The multi-type air-conditioning device includes a maintenance processing unit that in a case where one of the leakage detection sensors provided for one of the indoor units connected to the SP device detects leakage of a refrigerant, closes an SPL control valve and an SPG control valve corresponding to the one of the indoor units to stop operation of the one of the indoor units and maintains the indoor units other than the one of the indoor units to be operable, and a recovery processing unit that in a case where any of the leakage detection sensors provided for the plurality of indoor units connected to the MP device detects leakage of the refrigerant, causes a compressor to behave in a state where an MPL control valve and the SPL control valve are closed to recover the refrigerant remaining in each of the indoor heat exchangers to the compressor side, closes all of the MPG control valve and the SPG control valve after completion of recovery of the refrigerant, and stops the compressor.

Description

Technical Field

[0001] An embodiment of the present invention relates to a multi-type air-conditioning device.

Background Art

[0002] As a refrigerant for air-conditioning devices, refrigerants with low global warming potential (GWP), what is called low-GWP refrigerants, are being increasingly used these days. In general, however, low-GWP refrigerants are flammable refrigerants including mildly flammable refrigerants in many cases. Thus, in the case of using a flammable refrigerant, safety needs to be ensured when it leaks out from an apparatus.

[0003] Therefore, safety precautions required to be taken in accordance with the amount of refrigerant enclosed in an air-conditioning device as a whole, the capacity of a room in which an indoor unit is installed, and the like have been established in the Europe, for example. Examples of the safety precautions include methods such as installing a leakage detection sensor that detects leakage of a refrigerant in an indoor unit or in an indoor space in which the indoor unit is installed, and shutting off supply of the refrigerant to the indoor unit in a case where leakage of the refrigerant is detected.

[0004] On the other hand, it is requested that, in what is called a multi-type air-conditioning device in which a plurality of indoor units are connected in parallel in a single refrigeration cycle, indoor units other than an indoor unit from which the refrigerant has leaked out continue operation. Therefore, it is considered to configure a multi-type air-conditioning device, for example, such that a shut-off valve device including a shut-off valve is provided in a refrigerant flow passage of each of indoor units and only the shut-off valve of an indoor unit in which refrigerant leakage has been detected is closed, thereby continuing operation of indoor units in which refrigerant leakage has not been detected.

Citation List

Patent Literature

[0005] Patent Literature 1: International Publication No. WO 2019/102517

Summary of Invention

Technical Problem

[0006] Here, a kind of multi-type air-conditioning devices described above is what is called a multi-type air-conditioning device for simultaneous cooling and heating, which enables a cooling operation and a heating operation to be selected for each of indoor units, in other words, in which indoor units performing the cooling operation and indoor units performing the heating operation can be present in a mixed manner. In such a multi-type air-conditioning device for simultaneous cooling and heating, the number of refrigerant pipes between an outdoor unit and the indoor units increases. This raises a problem in that the number of shut-off valves for refrigerant control increases. Moreover, a shut-off valve device provided with such shut-off valves is commonly installed under the roof or the like, and thus an increase in the number of shut-off valve devices causes problems in that their installation place needs to be ensured and installation work is very burdensome.

[0007] Therefore, a multi-type air-conditioning device capable of simultaneously performing cooling and heating operations, which can ensure safety and reliability against leakage of a refrigerant while minimizing the number of vales, is provided.

Solution to Problem

[0008] A multi-type air-conditioning device of an embodiment is capable of simultaneously performing cooling and heating operations and includes: an outdoor unit having an outdoor heat exchanger and a compressor; a plurality of indoor units having indoor heat exchangers connected to the outdoor heat exchanger and the compressor, and leakage detection sensors capable of detecting leakage of the refrigerant; a single-port shut-off valve device capable of controlling distribution of the refrigerant to a refrigerant distribution passage to which one of the indoor units is connected; and a multi-port shut-off valve device capable of controlling distribution of the refrigerant to a plurality of refrigerant distribution passages to which a plurality of the indoor units are connected. The single-port shut-off valve device includes a single-port liquid-side control valve provided for the refrigerant distribution passage in the single-port shut-off valve device to control distribution of the refrigerant in a liquid state, and a single-port gas control valve provided for the refrigerant distribution passage in the single-port shut-off valve device to control distribution of the refrigerant in a gas state. The multi-port shut-off valve device includes a multi-port liquid-side control valve provided in common for the plurality of the indoor units in the multi-port shut-off valve device to control distribution of the refrigerant in the liquid state, and a multi-port gas control valve provided for the refrigerant distribution passage in the multi-port shut-off valve device to control distribution of the refrigerant in the gas state. The multi-type air-conditioning device includes: a maintenance processing unit capable of performing maintenance processing of, in a case where one of the leakage detection sensors provided for the one of the indoor units connected to the single-port shut-off valve device detects leakage of the refrigerant, closing the single-port liquid-side control valve and the single-port gas control valve corresponding to the one of the indoor units to stop operation of the one of the indoor units and maintaining the indoor units other than the one of the indoor units to be operable; and a recovery processing unit capable of performing recovery processing of, in a case where any of the leakage detection sensors provided for the plurality of the indoor units connected to the multi-port shut-off valve device detects leakage of the refrigerant, causing the compressor to behave in a state where the multi-port liquid-side control valve and the single-port liquid-side control valve are closed to recover the refrigerant remaining in each of the indoor heat exchangers to a side of the compressor, closing all of the multi-port gas control valve and the single-port gas control valve after completion of recovery of the refrigerant, and stopping the compressor.

Brief Description of Drawings

[0009] 

[Figure 1] Figure 1 is a refrigeration cycle diagram of a multi-type air-conditioning device according to an embodiment.

[Figure 2] Figure 2 is a refrigeration cycle diagram showing a flow of a refrigerant in a case where an overall heating operation is executed in the multi-type air-conditioning device.

[Figure 3] Figure 3 is a refrigeration cycle diagram showing a flow of the refrigerant in a case where an overall cooling operation is executed in the multi-type air-conditioning device.

[Figure 4] Figure 4 is a refrigeration cycle diagram showing a flow of the refrigerant in a case where a simultaneous heating and cooling operation is executed in the multi-type air-conditioning device.

[Figure 5] Figure 5 is a block diagram showing an electric configuration of the multi-type air-conditioning device.

[Figure 6] Figure 6 is a refrigeration cycle diagram showing a flow of the refrigerant in a case where recovery processing is executed in the multi-type air-conditioning device.

[Figure 7] Figure 7 is a control flow diagram showing an example of the content of control executed in the multi-type air-conditioning device.

Description of Embodiment

[0010] Hereinafter, an embodiment will be described with reference to the drawings.

[0011] An air-conditioning device 1 shown in Figure 1 is a multi-type air-conditioning device which includes a plurality of indoor units for a single outdoor unit and is capable of performing an overall heating operation, an overall cooling operation, and a simultaneous cooling and heating operation. The overall heating operation is an operation mode in which a heating operation is performed in all of the respective indoor units. The overall cooling operation is an operation mode in which a cooling operation is performed in all of the respective indoor units. The simultaneous heating and cooling operation are an operation mode in which indoor units performing the cooling operation and indoor units performing the heating operation are present in a mixed manner. In the following description, the overall heating operation, the overall cooling operation, and the simultaneous heating and cooling operation will be generically referred to as an air-conditioning operation in some cases.

[0012] The air-conditioning device 1 is configured to be capable of operating a plurality of indoor units 201, 202, 203, and 204 with a single outdoor unit 10. The air-conditioning device 1 includes, for example, the single outdoor unit 10, the plurality of indoor units 201 to 204, a single-port shut-off valve device 30, and a multi-port shut-off valve device 40. The outdoor unit 10, the respective indoor units 201 to 204, the single-port shut-off valve device 30, and the multi-port shut-off valve device 40 configure a single refrigeration cycle capable of circulating the refrigerant.

[0013] In the present embodiment, the single-port means that a shut-off valve device is configured to have a port pair for connecting an indoor unit, that is, a pair of refrigerant pipes to serve as an inlet and an outlet. The multi-port means that a shut-off valve device is configured to have a plurality of port pairs for connecting indoor units. In the following description, the single-port shut-off valve device 30 will be referred to as the SP device 30, and the multi-port shut-off valve device 40 will be referred to as the MP device 40 in some cases. Herein, the MP device 40 will be described using an example of having three port pairs to enable connection of three indoor units. Note that as the MP device 40, a model including four port pairs to enable connection of two indoor units or a model including at most sixteen port pairs to enable connection of eight indoor units can also be used. In other words, the MP device 40 is set such that the number of indoor units that can be connected thereto is more than or equal to two and less than or equal to eight. Moreover, in the present embodiment, a refrigerant distribution passage through which the refrigerant is distributed is configured by a refrigerant pipe. The number of indoor units depends on the total rating capabilities of the respective indoor units and a rating capability of the outdoor unit. In general, approximately three to fifteen indoor units can be connected to the single outdoor unit 10.

[0014] The outdoor unit 10 is installed outdoors. The outdoor unit 10 has an outdoor heat exchanger 11, an outdoor fan 12, an outdoor expansion valve 13, a compressor 14, a first switching valve 15, and a second switching valve 16 as shown in the refrigeration cycle diagram of Figure 1. The outdoor heat exchanger 11 has a function of exchanging heat between the refrigerant passing through the outdoor heat exchanger 11 and outside air. The outdoor fan 12 has a function of blowing air to the outdoor heat exchanger 11 to promote heat exchange in the outdoor heat exchanger 11. A mildly flammable or a flammable refrigerant is used as a refrigerant in the refrigeration cycle. In the present embodiment, mildly flammable R32, for example, is used as a refrigerant. The present embodiment will be described using an example in which the four indoor units 201 to 204 are connected to the outdoor unit 10.

[0015] The outdoor expansion valve 13 is connected to a liquid-side refrigerant pipe 56 directed from the outdoor unit 10 toward the indoor units 201 to 204. The outdoor expansion valve 13 has a function of adjusting the width of a flow passage of the refrigerant passing through the inside of the outdoor expansion valve 13 to depressurize the refrigerant, thereby adjusting a flow rate and pressure of the refrigerant flowed out of the outdoor heat exchanger 11 or the refrigerant flowing into the outdoor heat exchanger 11. The outdoor expansion valve 13 can be configured by an electronic expansion valve to be driven upon receipt of an electric signal from a computer (a micro control unit: MCU) provided for an outdoor control unit 17 of the outdoor unit 10 as shown in Figure 5, for example.

[0016] The first switching valve 15 and the second switching valve 16 have a function of switching a flow direction of the refrigerant in the refrigeration cycle, that is, a direction in which the refrigerant discharged from the compressor 14 flows. The first switching valve 15 and the second switching valve 16 are configured by a four-way valve to be driven upon receipt of an electric signal, for example, but a plurality of valves other than the four-way valve may be combined as long as the same flow of the refrigerant can be created.

[0017] The compressor 14 compresses the refrigerant flowing in the refrigeration cycle and discharges the refrigerant in a direction indicated by an open arrow in Figure 1, for example. In accordance with a switching state of the first switching valve 15 and the second switching valve 16, the compressor 14 sucks the refrigerant on the outdoor heat exchanger 11 side and discharges the sucked refrigerant to the MP device 40 and the SP device 30 side as shown in Figure 2, or sucks the refrigerant on the MP device 40 and the SP device 30 side and discharges the sucked refrigerant to the outdoor heat exchanger 11 side as shown in Figure 3.

[0018] Each of the indoor units 201 to 204 is installed in a room targeted for the air-conditioning operation. Each of the respective indoor units 201 to 204 has an indoor heat exchanger 21, an indoor fan 22, an indoor expansion valve 23, and a leakage detection sensor 24. Although the respective indoor units 201 to 204 can basically have an identical configuration, performance and the like of the indoor heat exchanger 21, the indoor expansion valve 23, the indoor fan 22, and the leakage detection sensor 24 can be modified as appropriate depending on the capacity of an installation space. In a case of distinguishing among the respective indoor units 201, 202, 203, and 204 in the following description, they will be referred to as the first indoor unit 201, the second indoor unit 202, the third indoor unit 203, and the fourth indoor unit 204, respectively, in some cases.

[0019] The indoor heat exchanger 21 exchanges heat between the refrigerant passing through the inside of the indoor heat exchanger 21 and air in the room in which each of the indoor units 201 to 204 is installed. The indoor heat exchanger 21 is connected to the outdoor heat exchanger 11 and the compressor 14 and configured to allow the refrigerant to circulate among the outdoor heat exchanger 11, the indoor heat exchanger 21, and the compressor 14. The indoor fan 22 has a function of blowing air to the indoor heat exchanger 21 to promote heat exchange in the indoor heat exchanger 21 and supplying air adjusted in temperature by the indoor heat exchanger 21 into the room.

[0020] The indoor expansion valve 23 has a function of adjusting the width of the flow passage of the refrigerant passing through the indoor expansion valve 23 to control a distributed amount of the refrigerant. The indoor expansion valve 23 can be configured by, for example, an electronic expansion valve to be driven upon receipt of an electric signal from a computer provided for an indoor control unit 25 of each of the indoor units 201 to 204 similarly to the outdoor expansion valve 13.

[0021] As shown in Figure 5, the respective indoor units 201 to 204 each have the indoor control unit 25. The SP device 30 and the MP device 40 each also have a control unit configured with a computer although not shown in detail in the drawing. The outdoor control unit 17 of the outdoor unit 10 and the indoor control unit 25 of each of the indoor units 201 to 204, and the control units not shown of the SP device 30 and the MP device 40 are mutually connected with communication lines to exchange various types of information.

[0022] The leakage detection sensor 24 has a function of detecting leakage of the refrigerant in each of the indoor units 201, 202, 203, and 204. The leakage detection sensor 24 may be incorporated in each of the indoor units 201 to 204 or may be installed independently as a leakage detection sensor unit in an indoor space of each room in which each of the indoor units 201 to 204 is installed. In the case of the present embodiment, each of the respective indoor units 201 to 204 is provided with the leakage detection sensor 24. The leakage detection sensor 24 can be configured by a semiconductor gas sensor, for example. The leakage detection sensor 24 possesses performance capable of detecting the refrigerant enclosed in the refrigeration cycle, herein, R32. The leakage detection sensor 24 outputs an electric signal for the refrigerant of approximately 300 to 30,000 ppm in the air, for example, the electric signal linearly changing in accordance with the concentration of the refrigerant. In a case where this detected concentration exceeds a predetermined value, the leakage detection sensor 24 reports an occurrence of refrigerant leakage to a corresponding one of the indoor units 201 to 204 and the outdoor unit 10.

[0023] The SP device 30 is configured to be capable of controlling distribution of the refrigerant to the single indoor unit 204, in this case, the fourth indoor unit 204, for example. The indoor heat exchanger 21 of the fourth indoor unit 204 is connected to the SP device 30. The SP device 30 is provided between the outdoor unit 10 and the fourth indoor unit 204. In other words, the outdoor unit 10 and the fourth indoor unit 204 are connected with the SP device 30 interposed therebetween. The SP device 30 has a single-port liquid-side control valve 31, two single-port gas control valves 321, 322, and a pressure relief valve 33. Hereinafter, the single-port liquid-side control valve 31 will be referred to as the SPL control valve 31 and the single-port gas control valves 321, 322 will be referred to as the SPG control valves 321, 322 in some cases.

[0024] The SPL control valve 31 is provided between liquid-side refrigerant pipes 511 and 512 that couple the outdoor heat exchanger 11 and the indoor heat exchanger 21 of the fourth indoor unit 204 and has a function of controlling distribution of the refrigerant in a liquid state. The liquid-side refrigerant pipe 51 is a distribution passage of liquid-side refrigerant, which is branched from the liquid-side refrigerant pipe 56 connected to the outdoor unit 10, and passes the refrigerant in the liquid state. The liquid-side refrigerant pipe 511 is a flow passage which has one end connected to the liquid-side refrigerant pipe 51 with the SPL control valve 31 interposed therebetween and the other end connected to the indoor heat exchanger 21 and which flows the liquid refrigerant to the indoor heat exchanger 21 of the fourth indoor unit 204.

[0025] The SPL control valve 31 can be configured by, for example, an electronic control valve capable of what is called electronic control, which is to be driven upon receipt of an electric signal. The SPL control valve 31 can be adjusted in an opening degree of the SPL control valve 31, that is, a flow rate of the refrigerant flowing in the liquid-side refrigerant pipe 51, in response to an electric signal from a control unit of the SP device 30 and also has a function as an on-off valve that completely shuts off distribution of the refrigerant in the liquid-side refrigerant pipe 51.

[0026] The SPG control valves 321, 322 are respectively provided on paths of the gas-side refrigerant pipes 52 and 521 or 522 and have a function of controlling distribution of the refrigerant in a gas state. The gas-side refrigerant pipes 52, 521, and 522 are distribution passages of the refrigerant, which couple the indoor heat exchanger 21 of the fourth indoor unit 204 and the compressor 14, and pass the refrigerant in the gas state. The gas-side refrigerant pipes 521 and 522 join on the way to become the single gas-side refrigerant pipe 52, which is connected to the indoor heat exchanger 21 of the fourth indoor unit 204. In this case, the liquid-side refrigerant pipe 511 and the gas-side refrigerant pipe 52 connected to the fourth indoor unit 204 configure a single refrigerant distribution passage to which the fourth indoor unit 204 is connected.

[0027] The SPG control valves 321 and 322 can be configured by, for example, an electronic control valve capable of what is called electronic control, which is to be driven upon receipt of an electric signal, and can be adjusted in opening degrees of the SPG control valves 321 and 322, that is, flow rates of the refrigerant flowing in the gas-side refrigerant pipes 521 and 522, on the basis of an electric signal from the control unit of the SP device 30. For example, one of the two SPG control valves 321 and 322 is adaptable to both high-pressure gas and low-pressure gas, and the other is adaptable only to low-pressure gas. In the present embodiment, the SPG control valve 321 is adaptable to both high-pressure gas and low-pressure gas, and the SPG control valve 322 is adaptable only to low-pressure gas. The air-conditioning device 1 can shut off the refrigerant flowing between the indoor heat exchanger 21 of the fourth indoor unit 204 and the compressor 14, that is, the refrigerant flowing in the gas-side refrigerant pipes 52, 521, and 522 by closing both the two SPG control valves 321 and 322.

[0028] The pressure relief valve 33 connects the liquid-side refrigerant pipe 51 and the gas-side refrigerant pipe 52. The pressure relief valve 33 has a function of, in a case where liquid seal or the like occurs so that the liquid-side refrigerant pipe 51 path comes to have an excessively high pressure, releasing part of the pressure to the gas-side refrigerant pipe 52.

[0029] The MP device 40 is provided between the outdoor unit 10 and all of the first indoor unit 201, the second indoor unit 202, and the third indoor unit 203. In other words, the outdoor unit 10 and all of the first indoor unit 201, the second indoor unit 202, and the third indoor unit 203 are connected with the MP device 40 interposed therebetween. The MP device 40 has a plurality of, in this case, three gas control valve units 41, 42, and 43 corresponding to the plurality of indoor units 201 to 203 connected to the MP device 40 and a multi-port liquid-side control valve 44. In a case of distinguishing among the respective gas control valve units 41, 42, and 43 in the following description, they will be referred to as the first gas control valve unit 41, the second gas control valve unit 42, and the third gas control valve unit 43, respectively, in some cases. The multi-port liquid-side control valve 44 will be referred to as the MPL control valve 44 in some cases.

[0030] The respective gas control valve units 41 to 43 each have two of the multi-port gas control valves 411, 412, 421, 422, 431, and 432. Hereinafter, the multi-port gas control valves 411, 412, 421, 422, 431, and 432 will also be referred to as the MPG control valves 411, 412, 421, 422, 431, and 432. The MPG control valves 411, 412, 421, 422, 431, and 432 are provided on paths of the gas-side refrigerant pipes 531, 532, 541, 542, 551, and 552, respectively, and have a function of controlling distribution of the refrigerant in the gas state.

[0031] The gas-side refrigerant pipes 531, 532, 541, 542, 551, and 552 are part of refrigerant distribution passages that couple the respective indoor heat exchangers 21 of the first indoor unit 201, the second indoor unit 202, and the third indoor unit 203 and the compressor 14 and pass the refrigerant in the gas state. The gas-side refrigerant pipes 531, 532, 541, 542, 551, and 552 join to become the gas-side refrigerant pipe 53, 54, and 55, respectively, which are connected to the respective indoor heat exchangers 21 of the respective indoor units 201, 202, and 203. In this case, the liquid-side refrigerant pipes 561 to 563 and the gas-side refrigerant pipes 53 to 55 connected to the indoor units 201 to 203, respectively, configure refrigerant distribution passages to which the respective indoor units 201 to 203 are connected, respectively.

[0032] The MPG control valves 411, 412, 421, 422, 431, and 432 can be configured by, for example, an electronic control valve capable of what is called electronic control, which is to be driven upon receipt of an electric signal, and can be adjusted in an opening degree, that is, a flow rate of the refrigerant flowing in a corresponding one of the gas-side refrigerant pipes 531, 532, 541, 542, 551, and 552 in response to an electric signal input from the control unit of the MP device 40, similarly to the SPG control valves 321 and 322.

[0033] In each of the gas control valve units 41, 42, and 43, one of two of the MPG control valves 411, 412, 421, 422, 431, and 432 is adaptable to both high-pressure gas and low-pressure gas, and the other is adaptable only to low-pressure gas. In the present embodiment, for example, the MPG control valves 411, 421, and 431 are adaptable to both high-pressure gas and low-pressure gas, and the MPG control valves 412, 422, and 432 are adaptable only to low-pressure gas. The air-conditioning device 1 can shut off the refrigerant flowing between the indoor heat exchanger 21 of each of the indoor units 201 to 203 and the compressor 14, that is, the refrigerant flowing in the gas-side refrigerant pipes 531, 532, 541, 542, 551, and 552 by closing the MPG control valves 411, 412, 421, 422, 431, and 432 that the respective gas control valve units 41, 42, and 43 have.

[0034] The MPL control valve 44 is provided on the way of the liquid-side refrigerant pipe 56 that couples the outdoor heat exchanger 11 and the indoor heat exchanger 21 of each of the indoor units 201 to 203, and has a function of controlling distribution of the refrigerant in the liquid state. The liquid-side refrigerant pipe 56 is a refrigerant distribution passage that couples the outdoor heat exchanger 11 and the indoor heat exchanger 21 of each of the indoor units 201 to 203 and passes refrigerant in the liquid state. The liquid-side refrigerant pipe 56 is branched to the liquid-side refrigerant pipes 561 to 563 on the respective indoor units 201 to 203 side with respect to the MPL control valve 44, and each of the liquid-side refrigerant pipes 561 to 563 is connected to one end of the indoor heat exchanger 21 of each of the indoor units 201 to 203.

[0035] Although the MP device 40 is described in the present embodiment using the example in which the three indoor units 201 to 203 can be connected, there are also models, in other words, types, to which two and four or more indoor units are connected. In any model, only the single MPL control valve 44 is provided for the liquid-side refrigerant pipe 56. This configuration accomplishes simplification of the refrigerant circuit and pipe routing. Note that a required number of the MPG control valves 411, 412, 421, 422, 431, and 432 is twice as many as the number of the indoor units 201 to 203 to be connected.

[0036] The MPL control valve 44 can be configured by, for example, an electronic control valve capable of what is called electronic control, which is to be driven upon receipt of an electric signal, and can be adjusted in an opening degree, that is, a flow rate of the refrigerant flowing in the liquid-side refrigerant pipe 51, on the basis of electric control exerted by the control unit of the MP device 40, and has a function of completely shutting off distribution of the refrigerant in the liquid-side refrigerant pipe 56.

[0037] One of the plurality of gas control valve units 41 to 43 has a pressure relief valve 413. In the case of the present embodiment, the first gas control valve unit 41 has the pressure relief valve 413. The pressure relief valve 413 connects the liquid-side refrigerant pipe 561 and the gas-side refrigerant pipe 53. The pressure relief valve 413 has a function of, in a case where the liquid-side refrigerant pipe 561 side is brought into a liquid seal state and comes to have an excessively high pressure, releasing part of the pressure to the gas-side refrigerant pipe 53.

[0038] In Figure 2 to Figure 4 and Figure 6, black thick lines and open arrows in the refrigerant distribution passages are intended for describing a main flow of the refrigerant in each operation and are different from an actual flow of the refrigerant in some cases. In other words, portions not indicated by the black thick lines are actually filled with the refrigerant in some cases.

[0039] In the case of executing the overall heating operation, the air-conditioning device 1 switches the first switching valve 15 to a mode of connecting a sucking side of the compressor 14 and the outdoor heat exchanger 11 and switches the second switching valve 16 to a mode of connecting a discharging side of the compressor 14 and the indoor heat exchanger 21 of each of the indoor units 201 to 204, as shown in Figure 2. In the overall heating operation, the outdoor heat exchanger 11 functions as an evaporator, and the indoor heat exchangers 21 of all of the indoor units 201 to 204 function as condensers.

[0040] In this case, looking at the SP device 30, the air-conditioning device 1 closes the SPG control valve 322 adaptable only to low-pressure gas and opens the SPG control valve 321 adaptable to high-pressure gas and low-pressure gas. Looking at the MP device 40, the air-conditioning device 1 closes the MPG control valves 412, 422, and 432 adaptable only to low-pressure gas and opens the MPG control valves 411, 421, and 431 adaptable to high-pressure gas and low-pressure gas. Then, each of the indoor units 201 to 204 controls the opening degree of the indoor expansion valve 23 of its own, thereby adjusting output of heating in each of the indoor units 201 to 204.

[0041] In the case of executing the overall cooling operation, the air-conditioning device 1 switches the first switching valve 15 to a mode of connecting the discharging side of the compressor 14 and the outdoor heat exchanger 11 and switches the second switching valve 16 to a mode of connecting the sucking side of the compressor 14 and the indoor heat exchanger 21 of each of the indoor units 201 to 204, as shown in Figure 3. In the overall cooling operation, the outdoor heat exchanger 11 functions as a condenser, and the indoor heat exchangers 21 of all of the indoor units 201 to 204 function as evaporators.

[0042] In this case, looking at the SP device 30, the air-conditioning device 1 closes the SPG control valve 322 adaptable only to low-pressure gas and opens the SPG control valve 321 adaptable to high-pressure gas and low-pressure gas, similarly to the time of the overall heating operation. Looking at the MP device 40, the air-conditioning device 1 closes the MPG control valves 412, 422, and 432 adaptable only to low-pressure gas and opens the MPG control valves 411, 421, and 431 adaptable to high-pressure gas and low-pressure gas. Then, each of the indoor units 201 to 204 controls the opening degree of the indoor expansion valve 23 of its own, thereby adjusting output of cooling in each of the indoor units 201 to 204.

[0043] In the case of executing the simultaneous heating and cooling operation, the air-conditioning device 1 performs operation based on the overall heating operation shown in Figure 2 or the overall cooling operation shown in Figure 3. Then, the air-conditioning device 1 closes the MPG control valves 411, 421, and 431 adaptable to high-pressure and low-pressure gas and opens the MPG control valves 412, 422, and 432 adaptable only to low-pressure gas among the plurality of gas refrigerant control valves 321, 322, 411, 412, 421, 422, 431, and 432 connected to any of the indoor units 201 to 204 that performs operation different from others, so that the flow direction of the refrigerant to any of the indoor units 201 to 204 that performs operation different from the others is reversed from the others of the indoor units 201 to 204. The air-conditioning device 1 can thereby perform a reverse operation from the basic operation for some of the indoor units 201 to 204.

[0044] An example shown in Figure 4, for example, is a mode which is based on the overall heating operation and in which only the third indoor unit 203 among the respective indoor units 201 to 204 performs the cooling operation. In this case, the air-conditioning device 1 closes the MPG control valve 431 adaptable to high-pressure and low-pressure gas between the MPG control valves 431 and 432 connected to the indoor heat exchanger 21 of the third indoor unit 203 and opens the MPG control valve 432 adaptable to low-pressure gas. Then, the refrigerant having been heat dissipated in the indoor heat exchangers 21 of the indoor units 201, 202, and 204 other than the third indoor unit 203 flows into the indoor heat exchanger 21 of the third indoor unit 203, so that only the indoor heat exchanger 21 of the third indoor unit 203 functions as an evaporator. Accordingly, the heating operation is performed in the first indoor unit 201, the second indoor unit 202, and the fourth indoor unit 204, and the cooling operation is performed in the third indoor unit 203.

[0045] Note that whether the cooling and heating mixed operation is based on the overall heating operation or based on the overall cooling operation can be determined depending on a proportion occupied by the heating operation or the cooling operation in the whole. When performing the cooling and heating mixed operation, the air-conditioning device 1 can determine that the basic operation is the overall heating operation if, for example, the heating operation occupies a large proportion in the whole, and determine that the basic operation is the overall cooling operation if the cooling operation occupies a large proportion in the whole.

[0046] Next, an electric configuration of the air-conditioning device 1 will be described with reference to Figure 5. The outdoor unit 10 further has the outdoor control unit 17. The respective indoor units 201 to 204 each further has an indoor control unit 25. The outdoor control unit 17 and the indoor control unit 25 can be configured to include a computer or the like having an arithmetic unit such as a CPU, a transitory storage medium such as a RAM, a non-transitory storage medium such as a ROM or a main memory that stores a control program of an apparatus, and the like, for example.

[0047] The outdoor control unit 17 controls an overall behavior of the air-conditioning device 1. The outdoor fan 12, the outdoor expansion valve 13, the compressor 14, the first switching valve 15, and the second switching valve 16 are electrically connected to the outdoor control unit 17. The outdoor control unit 17 controls behaviors of the outdoor fan 12, the outdoor expansion valve 13, the compressor 14, the first switching valve 15, and the second switching valve 16.

[0048] The indoor control units 25 of the respective indoor units 201 to 204 are each electrically connected to the outdoor control unit 17 in such a manner that communication can be made. The indoor fan 22, the indoor expansion valve 23, and the leakage detection sensor 24 of each of the indoor units 201 to 204 are electrically connected to the indoor control unit 25 of each of the indoor units 201 to 204. The indoor control unit 25 of each of the indoor units 201 to 204 controls behaviors of the indoor fan 22, the indoor expansion valve 23, and the leakage detection sensor 24 of each of the indoor units 201 to 204 on the basis of a command from the outdoor control unit 17. A result of detection obtained by the leakage detection sensor 24 provided for each of the indoor units 201 to 204 is transmitted to the outdoor control unit 17 via the indoor control unit 25 of each of the indoor units 201 to 204.

[0049] The SP device 30 and the MP device 40 behave upon receipt of a command from the outdoor control unit 17 via the indoor control unit 25. For example, the SP device 30 is electrically connected to the indoor control unit 25 of the fourth indoor unit 204 targeted to be controlled by the SP device 30 in such a manner that communication can be made. In this case, the indoor control unit 25 of the fourth indoor unit 204 controls a behavior of the SP device 30 on the basis of a command from the outdoor control unit 17. The MP device 40 is electrically connected to the indoor control unit 25 of one of the respective indoor units 201 to 203 targeted to be controlled by the MP device 40. In the case of the present embodiment, the MP device 40 is electrically connected to the indoor control unit 25 of the first indoor unit 201. Then, the indoor control unit 25 of the first indoor unit 201 controls a behavior of the MP device 40 on the basis of a command from the outdoor control unit 17. Note that the SP device 30 and the MP device 40 may be configured to behave upon receipt of a command directly from the outdoor control unit 17 without intervention of the indoor control unit 25. As described, in the present embodiment, the outdoor control unit 17 plays a leading role of instructing all of the indoor units 201 to 204, the SP device 30, and the MP device 40 to control a behavior of each apparatus.

[0050] The air-conditioning device 1 further includes a maintenance processing unit 171, a recovery processing unit 172, an overall stop processing unit 173, a setting processing unit 174, a first report processing unit 175, and a second report processing unit 176 as shown in Figure 5. The maintenance processing unit 171, the recovery processing unit 172, the overall stop processing unit 173, the setting processing unit 174, the first report processing unit 175, and the second report processing unit 176 may be realized when the CPU possessed by the outdoor control unit 17 executes a predetermined program, for example. Alternatively, the maintenance processing unit 171, the recovery processing unit 172, the overall stop processing unit 173, the setting processing unit 174, the first report processing unit 175, and the second report processing unit 176 may be realized only by hardware such as an integrated circuit in which a predetermined program is implemented, or some functions may be realized by dedicated hardware, and others may be realized by a combination of hardware and a program. Still alternatively, the maintenance processing unit 171, the recovery processing unit 172, the overall stop processing unit 173, the setting processing unit 174, the first report processing unit 175, and the second report processing unit 176 may be realized as functions of the indoor control unit 25 rather than the outdoor control unit 17, or may be realized as functions separately possessed by the outdoor control unit 17 and the indoor control unit 25.

[0051] The maintenance processing unit 171 is capable of executing maintenance processing of, in a case where the leakage detection sensor 24 provided for an indoor unit connected to the SP device 30, in this case, the fourth indoor unit 204, detects leakage of the refrigerant, closing at least the SPL control valve 31 and the SPG control valves 321, 322 positioned in the refrigerant distribution passage of the indoor unit 204 to disconnect the indoor unit 204 from the refrigeration cycle, that is, the refrigerant distribution passage, thereby preventing leakage by more than or equal to the amount of the refrigerant present in the indoor unit 204, stopping operation of the fourth indoor unit 204, and maintaining the indoor units 201 to 203 other than the indoor unit 204 to be operable. The maintenance processing is processing that can be executed only in the case where leakage of the refrigerant occurs in an indoor unit connected to the SP device 30 and is not executed in a case where leakage of the refrigerant occurs in any of the indoor units 201 to 203 connected to the MP device 40.

[0052] The outdoor control unit 17 may be configured to, in the case where the maintenance processing is executed, report that refrigerant leakage has occurred to a user, a maintenance company, or the like using, for example, a speaker or a display not shown but connected to the outdoor control unit 17 or using an external device connected via an electric communication line. Then, in the case where the maintenance processing is executed, the outdoor control unit 17 accepts handling indicating that the air-conditioning operation is to be performed for the indoor units 201 to 203 other than the indoor unit 204 from users similarly to a normal state.

[0053] The recovery processing unit 172 is capable of executing recovery processing. The recovery processing includes processing of causing the compressor 14 to behave in a state where the MPL control valve 44 and the SPL control valve 31 are closed to recover the refrigerant remaining in each of the indoor heat exchangers 21 to the compressor 14 side as shown in Figure 6. The recovery processing unit 172 executes the recovery processing in a case where at least one of the leakage detection sensors 24 provided respectively for the plurality of indoor units 201 to 203 connected to the MP device 40 detects leakage of the refrigerant. The recovery processing unit 172 also executes the recovery processing in a case where the recovery processing has been set in a setting processing which will be described later in a case where the leakage detection sensor 24 provided for the indoor unit 204 connected to the SP device 30 detects leakage of the refrigerant.

[0054] The recovery processing is processing to be executed in the case where leakage of the refrigerant has occurred in the indoor units 201 to 203 connected to the MP device 40 or in a case where leakage of the refrigerant has occurred in the indoor unit 204 connected to the SP device 30 and it has been set such that the recovery processing is to be executed by priority over the maintenance processing. When the recovery processing is executed, the recovery processing unit 172 first closes the SPL control valve 31 and the MPL control valve 44 to shut off supply of the refrigerant to the indoor heat exchangers 21 of all of the indoor units 201 to 204 included in the air-conditioning device 1.

[0055] Moreover, the recovery processing unit 172 brings all of the valves 23, 411, 412, 421, 422, 431, 432, 321, and 322 of the MP device 40, the SP device 30, and the indoor units 201 to 204 except the MPL control valve 44 and the SPL control valve 31 into a fully open state or a state with a large opening degree such that the refrigerant can be distributed smoothly to cause the compressor 14 to behave. At this time, the recovery processing unit 172 maintains the first switching valve 15 in the mode of connecting the discharging side of the compressor 14 and the outdoor heat exchanger 11, and maintains the second switching valve 16 in the mode of connecting the sucking side of the compressor 14 and the indoor heat exchanger 21 of each of the indoor units 201 to 204.

[0056] In other words, the recovery processing unit 172 maintains the first switching valve 15 and the second switching valve 16 in the same mode as in the overall cooling operation shown in Figure 3. The refrigerant remaining in the indoor heat exchanger 21 of each of the indoor units 201, 202, 203, and 204 is thereby recovered to the compressor 14 side. Consequently, the refrigerant is removed from the indoor heat exchangers 21 of all of the indoor units 201 to 204, so that further leakage of the refrigerant is prevented. Then, after operating the compressor 14 to perform recovery of the refrigerant for a certain period, the recovery processing unit 172 fully closes the respective MPG control valves 411, 412, 421, 422, 431, 432 and the respective SPG control valves 321, 322 being open, and thereafter stops the compressor 14 to complete the recovery processing. Note that it is not particularly necessary to close the indoor expansion valves 23 of the respective indoor units 201 to 204 as distribution of the refrigerant has already been blocked by the SPL control valve 31 and the MPL control valve 44 positioned upstream of the indoor expansion valves 23.

[0057] The overall stop processing unit 173 is processing to be executed after completion of the recovery processing and is processing of subsequently disallowing operation behaviors of the compressor 14 of the outdoor unit 10, all of the indoor units 201 to 204, the SP device 30, and the MP device 40.

[0058] Then, the outdoor control unit 17 denies subsequent user instructions for performing the air-conditioning operation, issued from all of the indoor units 201 to 204, by executing the overall stop processing. Thereafter, operation of the air-conditioning device 1 can be started again, for example, after a maintenance person repairs a leaked location to return to the normal state and then cancels the overall stop processing by special handling.

[0059] The setting processing unit 174 is capable of executing the setting processing. The setting processing is processing of, in the case where the leakage detection sensor 24 provided for any of the indoor units 201 to 203 connected to the SP device 30 detects leakage of the refrigerant, setting in advance, that is, prior to the operation of the air-conditioning device 1, which of the maintenance processing and the recovery processing is to be executed on the basis of input from a user, in other words, an administrator or the like of the air-conditioning device 1. This setting can be input using an input device directly provided for the outdoor control unit 17, a personal computer, a portable terminal, or the like indirectly connected via an electric communication line, for example.

[0060] In the case where the leakage detection sensor 24 detects leakage of the refrigerant, the outdoor control unit 17 reports that refrigerant leakage has occurred to a user, a maintenance company, or the like using a report unit 177 connected to the outdoor control unit 17 shown in Figure 5. The report unit 177 is, for example, a speaker, a display, or the like provided for the outdoor unit 10 or each of the indoor units 201 to 204, and additionally is an external device connected via an electric communication line, such as, for example, a server or a portable terminal or the like of a maintenance company.

[0061] The air-conditioning device 1 differentiates the content of report between the case where leakage of the refrigerant has been detected in the indoor unit 204 connected to the SP device 30 and the case where leakage of the refrigerant has been detected by any of the indoor units 201 to 203 connected to the MP device 40. In this case, the air-conditioning device 1 reports an abnormality together with a cause of the abnormality to allow a user to distinguish the state of the abnormality, thereby avoiding user confusion.

[0062] The air-conditioning device 1 includes the first report processing unit 175 and the second report processing unit 176 as processing units for executing the above-described report. In the case where the maintenance processing is executed, the first report processing unit 175 executes first report processing. The first report processing is processing of reporting that an indoor unit from which the refrigerant has leaked out is not operable, but the indoor units other than the indoor unit from which the refrigerant has leaked out can continue operation to a user, a maintenance company, or the like using the report unit 177 or the like. In other words, the content of report in the first report processing includes information indicating that an abnormality has occurred in the air-conditioning device 1 but the indoor units 201 to 203 connected to the MP device 40 can continue operation. The second report processing unit 176 executes second report processing in the case where the overall stop processing is executed. The second report processing is processing of reporting that none of the indoor units 201 to 204 is operable to a user, a maintenance company, or the like using the report unit 177 or the like.

[0063] Next, a control flow in the case where leakage of the refrigerant has occurred in any of the respective indoor units 201 to 204 will be described with reference to Figure 7. Note that in the following description, the outdoor control unit 17 shall play a leading role in executing processing in each of the maintenance processing unit 171, the recovery processing unit 172, the overall stop processing unit 173, the setting processing unit 174, the first report processing unit 175, and the second report processing unit 176. The setting processing shall be executed by the setting processing unit 174 prior to the air-conditioning operation.

[0064] The outdoor control unit 17 monitors leakage of the refrigerant in each of the indoor units 201 to 204 on the basis of output of the leakage detection sensor 24 of each of the indoor units 201 to 204 by way of the indoor control unit 25 of each of the indoor units 201 to 204 all the time during operation of the air-conditioning device 1. In a case where refrigerant leakage is detected in none of the indoor units 201 to 204 (NO in step S11), the outdoor control unit 17 repeats step S11. On the other hand, when refrigerant leakage is detected in at least one of the respective indoor units 201 to 204 (YES in step S11), the outdoor control unit 17 transitions the process to step S12.

[0065] The outdoor control unit 17 determines in step S12 in which of the indoor units 201 to 204 refrigerant leakage has been detected. In other words, the outdoor control unit 17 determines in step S12 whether a connection destination of the one of the indoor units 201 to 204 in which refrigerant leakage has been detected is the SP device 30 or the MP device 40.

[0066] In the case where the connection destination of the one of the indoor units 201 to 204 in which refrigerant leakage has been detected is the SP device 30 (SP DEVICE in step S12), that is, in the case where the indoor unit in which refrigerant leakage has been detected is the fourth indoor unit 204, the outdoor control unit 17 transitions the process to step S13. The outdoor control unit 17 determines in step S13 whether the content of setting in the setting processing is the "maintenance processing" or the "recovery processing". In the case where the "maintenance processing" has been set, the outdoor control unit 17 transitions the process to step S14.

[0067] Then, the outdoor control unit 17 executes the above-described maintenance processing in step S14 to stop operation of the indoor unit 204 coupled to the SP device 30, close the SPL control valve 31 and the SPG control valves 321, 322 in the SP device 30 to disconnect the indoor unit 204 from the refrigerant path, and maintain the indoor units 201 to 203 other than the indoor unit 204 to be operable. Next, the outdoor control unit 17 executes the first report processing in step S15 to report, to a user or the like, that an abnormality in which the refrigerant leaks out has occurred in the air-conditioning device 1, and the indoor unit 204 from which the refrigerant has leaked out is not operable, but the remaining indoor units 201 to 203 can continue operation. Thereafter, the outdoor control unit 17 returns the process to step S11 and executes step S11 and the subsequent steps again.

[0068] In the case where the connection destination of the one of the indoor units 201 to 204 in which refrigerant leakage has been detected is the MP device 40 (MP DEVICE in step S12), that is, in the case where the indoor unit in which refrigerant leakage has been detected is any of the first indoor unit 201, the second indoor unit 202, or the third indoor unit 203, the outdoor control unit 17 transitions the process to step S15. In the case where leakage of the refrigerant is detected in the indoor unit 204 connected to the SP device 40 ("SP DEVICE" in step S12) and the content of setting in the setting processing has been set at the "recovery processing" ("RECOVERY PROCESSING" in step S13), the outdoor control unit 17 transitions the process to step S15.

[0069] The outdoor control unit 17 executes the above-described recovery processing in step S15 to recover refrigerant remaining in the indoor heat exchanger 21 of each of the indoor units 201 to 204 to the compressor 14 side. Thereafter, the outdoor control unit 17 executes the above-described overall stop processing in step S16 to disallow restart of each of the indoor units 201 to 204. Next, the outdoor control unit 17 executes the second report processing in step S17 to report that none of the indoor units 201 to 204 is operable. Then, the outdoor control unit 17 terminates the sequential processing (END).

[0070] According to the embodiment described above, the multi-type air-conditioning device 1 is capable of simultaneously performing cooling and heating operations and includes the outdoor unit 10, the plurality of indoor units 201 to 204, the SP device 30, and the MP device 40. The outdoor unit 10 has the outdoor heat exchanger 11 and the compressor 14. The indoor units 201 to 204 each have the indoor heat exchanger 21 connected to the outdoor heat exchanger 11 and the compressor 14, and the leakage detection sensor 24 capable of detecting leakage of the refrigerant. The SP device 30 is configured to be capable of controlling distribution of the refrigerant to the liquid-side refrigerant pipe 511 and the gas-side refrigerant pipe 52 which are one refrigerant distribution passage to which the indoor unit 204 is connected. The MP device 40 is configured to be capable of controlling distribution of the refrigerant to the liquid-side refrigerant pipes 561 to 563 and the gas-side refrigerant pipes 53 to 55 which are a plurality of refrigerant distribution passages to which the plurality of indoor units 201 to 203 are connected.

[0071] The SP device 30 has the SPL control valve 31 and the SPG control valves 321, 322. The SPL control valve 31 is provided for the liquid-side refrigerant pipe 511 which is a refrigerant distribution passage in the SP device 30 and has a function of controlling distribution of the refrigerant in the liquid state. In other words, the single SPL control valve 31 is provided for the single indoor heat exchanger 21. The SPG control valves 321, 322 are provided for the gas-side refrigerant pipe 52 which is a refrigerant distribution passage in the SP device 30 and has a function of controlling distribution of the refrigerant in the gas state.

[0072]  The MP device 40 has the MPL control valve 44 and the MPG control valves 411, 412, 421, 422, 431, and 432. The MPL control valve 44 is provided in common for the plurality of indoor units 201, 202, and 203 in the MP device 40 and has a function of controlling distribution of the refrigerant in the liquid state. The MPG control valves 411, 412, 421, 422, 431, and 432 are provided for the gas-side refrigerant pipes 53 to 55 which are refrigerant distribution passages in the MP device 40 and have a function of controlling distribution of the refrigerant in the gas state.

[0073] The MP device 40 thereby has the MPL control valve 44 common to the plurality of indoor units 201 to 203. In other words, adoption of the MP device 40 eliminates the need to provide the MPL control valve 44 for each of the plurality of indoor units 201 to 203. The present embodiment can thereby reduce the number of control valves as compared with a case of connecting the SP device 30 to all of the indoor units 201 to 204. Accordingly, the number of components can be reduced to reduce manufacturing cost, and the number of control valves having driving units can be reduced to improve maintenance performance and durability of the air-conditioning device 1.

[0074] It is also requested to continue operation of the air-conditioning device 1 when possible as long as safety is ensured even in the case where the refrigerant has leaked out. On the other hand, it is necessary to reliably stop operation of the air-conditioning device 1 in a case where safety is threatened by leakage of the refrigerant. Herein, the single indoor unit 204 is commonly connected to the single SP device 30. On the other hand, the plurality of indoor units 201 to 203 are connected to the single MP device 40. The amount of the refrigerant downstream of the SP device 30 is proportionate to the capacities of the indoor heat exchanger 21 of the indoor unit 204 connected with the pipes to the port pair of this SP device 30 and the pipes therebetween. On the other hand, the amount of the refrigerant on the downstream side of the MP device 40 is proportionate to the capacities of all of the indoor heat exchangers 21 of the plurality of indoor units 201 to 203 connected to the respective port pairs of the MP device 40 and the pipes therebetween. Since the plurality of indoor units 201 to 203 are connected to the MP device 40, the amount of the refrigerant downstream of the MP device 40 is in principle several times as large as the amount of the refrigerant downstream of the SP device 30 to which only the single indoor unit 204 is connected. In other words, the amount of the refrigerant on the downstream side of the SP device 30 is small.

[0075] The total of cooling rating capabilities of the indoor units connected to the MP device 40 is 70 to 110 kW while a cooling rating capability of the indoor unit that can be connected to the SP device 30 is at most approximately 28 kW, for example. Since the capacity of the indoor heat exchanger of an indoor unit is generally proportionate to the cooling rating capability of the indoor unit, the amount of the refrigerant on the downstream side of the SP device 30 is approximately 1/3 to 1/4 of the amount of the refrigerant on the downstream side of the MP device 40. Consequently, if an indoor unit in which leakage of the refrigerant has been detected is shut off and disconnected from the refrigeration cycle, an absolute amount of leaked the refrigerant in the case where the refrigerant leaks out from the indoor unit 204 connected to the SP device 30 is smaller and the influence caused by refrigerant leakage is smaller than in the case where the refrigerant leaks out from any of the indoor units 201 to 203 connected to the MP device 40.

[0076] Therefore, the air-conditioning device 1 having the above-described configuration further includes the maintenance processing unit 171. The maintenance processing unit 171 is capable of executing the maintenance processing. The maintenance processing includes processing of, in the case where the leakage detection sensor 24 provided for the indoor unit 204 connected to the SP device 30 detects leakage of the refrigerant, closing the SPL control valve 31 and the SPG control valves 321, 322 of the indoor unit 204, that is, shutting off distribution of the refrigerant, to stop operation of the indoor unit 204. By disconnecting the indoor unit 204 from the refrigerant distribution path in the refrigeration cycle as described, the refrigerant present in the indoor units 201 to 203 other than the indoor unit 204, the outdoor unit 10, and their pipes is inhibited from flowing into the indoor unit 204. As a result, the amount of leakage of the refrigerant from the indoor unit 204 can be kept falling within a range of the refrigerant held by the indoor unit 204 itself. Then, the maintenance processing includes processing of maintaining the indoor units 201 to 203 other than the indoor unit 204 to be operable upon taking measures described above for inhibiting refrigerant leakage.

[0077] Accordingly, in the case where refrigerant leakage occurs in the indoor unit 204 connected to the SP device 30 less affected by refrigerant leakage, operation of only the indoor unit 204 connected to the SP device 30 is stopped, and operation of the other indoor units, that is, the indoor units 201 to 203 connected to the MP device 40, can be continued. Thus, the present embodiment enables user convenience to be improved without safety and reliability impaired by leakage of the refrigerant.

[0078] On the other hand, the distributed amount of the refrigerant in the MP device 40 is larger than the distributed amount of the refrigerant in the SP device 30. The MP device 40 is provided only with the single MPL control valve 44 between the MP device 40 and the liquid-side refrigerant pipe 56. Thus, in the case where refrigerant leakage is detected in any of the indoor units 201 to 203 connected to the MP device 40, refrigerant distribution to/from another refrigeration cycle apparatus including the outdoor unit 10 can be blocked if all of the MPL control valve 44 and the MPG control valves 411, 412, 421, 422, 431, and 432 are shut off, but the refrigerant can flow back and forth among the respective indoor units 201 to 203 through the liquid-side refrigerant pipes 561 to 563. Thus, in the case where refrigerant leakage occurs in any of the indoor units 201 to 203, the refrigerant present in the other indoor units connected to the MP device 40 from which the refrigerant has not been leaked out and their pipes might flow into the indoor unit from which the refrigerant has leaked out, so that a large amount of the refrigerant might leak out. In other words, in the case where the refrigerant leaks out from any of the indoor units 201 to 203 connected to the MP device 40, the amount of leaked refrigerant is larger and the influence caused by refrigerant leakage is greater than in the case where the refrigerant leaks out from the indoor unit 204 connected to the SP device 30.

[0079] Therefore, the air-conditioning device 1 having the above-described configuration further includes the recovery processing unit 172 and the overall stop processing unit 173. The recovery processing unit 172 executes the recovery processing of recovering the refrigerant present in the indoor units 201 to 204 to the outdoor unit 10 side. In the recovery processing, in the case where at least one of the leakage detection sensors 24 provided respectively for the plurality of indoor units 201 to 203 connected to the MP device 40 detects leakage of the refrigerant, the compressor 14 is caused to behave in the state where the MPL control valve 44 and the SPL control valve 31 are closed, thereby recovering the refrigerant remaining in the heat exchanger 21 of each of the indoor units 201 to 204, in this case, all of the indoor heat exchangers 21 included in the air-conditioning device 1 and their peripheral pipes 511, 561 to 563, and 52 to 55 to the compressor 14 side. In this case, the MPG control valves 411, 412, 421, 422, 431, 432 and the SPG control valves 321, 322 are maintained in the open state. Then, in the recovery processing, all of the MPG control valves 411, 412, 421, 422, 431, 432 and the SPG control valves 321, 322 are shut, in other words, closed, after completion of recovery of the refrigerant described above to stop the compressor 14. As a result, the refrigerant is hardly present in all of the indoor units 201 to 204, so that further refrigerant leakage is inhibited.

[0080] Herein, in the case where leakage of the refrigerant has occurred in the indoor unit 204 connected to the SP device 30, there is no obstacle to continuing operation of the other indoor units 201 to 203 by disconnecting the indoor unit 204 from the refrigeration cycle as described above. However, in order to place top priority on safety, there is also a need for executing the recovery processing even in the case where leakage of the refrigerant has occurred in the indoor unit 204 connected to the SP device 30.

[0081] Therefore, the air-conditioning device 1 further includes the setting processing unit 174 capable of executing the setting processing. The setting processing includes processing of setting, on the basis of a user input, which of the maintenance processing and the recovery processing is to be executed in the case where the leakage detection sensor 24 provided for the indoor unit 204 connected to the SP device 30 detects leakage of the refrigerant. Then, in the case where the leakage detection sensor 24 provided for the indoor unit 204 connected to the SP device 30 detects leakage of the refrigerant, the recovery processing unit 172 executes the recovery processing in the case where the recovery processing has been set in the setting processing. In other words, in the case where the leakage detection sensor 24 provided for the indoor unit 204 connected to the SP device 30 detects leakage of the refrigerant, the recovery processing unit 172 executes the maintenance processing without executing the recovery processing in the case where the maintenance processing has been set in the setting processing.

[0082] This allows a user to set at user's discretion on which of the maintenance processing and the recovery processing priority is to be placed in the case where refrigerant leakage occurs in the indoor unit 204 connected to the SP device 30. As a result, the air-conditioning device 1 which can improve user convenience and suits user's needs can be provided.

[0083] The air-conditioning device 1 further includes the overall stop processing unit 173 capable of executing the overall stop processing of disallowing operation of all of the indoor units 201 to 204 after completion of the recovery processing. In other words, the overall stop processing unit 173 which behaves subsequent to the recovery processing unit 172 executes the overall stop processing of disallowing subsequent operation of all of the indoor units 201 to 204.

[0084] The refrigerant is thereby recovered from all of the indoor units 201 to 204 in the case where the refrigerant leakage occurs in the indoor units 201 to 203 connected to the MP device 40, and thereafter, operation of all of the indoor units 201 to 204 is stopped. This can prevent refrigerant leakage from broadening further to ensure safety.

[0085] Note that as additional description for confirmation, in a case where the plurality of SP devices 30 is connected to the outdoor unit 10 and the maintenance processing has been set and if leakage is detected in an indoor unit connected to any of the SP devices 30, the SP device 30 is shut off from the refrigeration cycle, but the other SP devices and indoor units connected to those SP devices 30 continue operating as they are. On the other hand, when the recovery processing is set, the refrigerant is recovered from all of the SP devices 30 and the MP device 40, and operation is disallowed.

[0086] As to the above-described selection and setting of the maintenance processing and the recovery processing of the SP device 30, setting shall be performed uniformly in the whole system of the air-conditioning device 1, however, in the case where the plurality of SP devices 30 is connected, it may be configured such that setting can be made for an individual one of the SP devices 30 or each of indoor units connected to each of the SP devices 30. In this case, if the "maintenance processing" has been set for an indoor unit in which leakage of the refrigerant is detected or the SP device 30 corresponding to that indoor unit and when the refrigerant leakage from the indoor unit is detected, the shut-off valve of the corresponding SP device 30 only shuts off distribution of the refrigerant, and the other SP devices 30 and the MP device 40 can continue the air-conditioning operation. On the other hand, if the "recovery processing" has been set for an indoor unit in which leakage of the refrigerant is detected or the SP device 30 corresponding to that indoor unit and in the case where refrigerant leakage from the indoor unit is detected, refrigerant recovery is carried out in the sequential refrigeration cycle as a whole, and a subsequent air-conditioning operation is disallowed in indoor units connected to all of the SP devices 30 and the MP device 40.

[0087] The air-conditioning device 1 further includes the first report processing unit 175 capable of executing the first report processing or the second report processing unit 176 capable of executing the second report processing. The first report processing is processing of, in the case where the maintenance processing is executed, reporting that an indoor unit from which the refrigerant has leaked out is not operable, but indoor units other than the indoor unit from which the refrigerant has leaked out can continue operation. The second report processing is processing of, in the case where the overall stop processing is executed, reporting that none of the indoor units is operable. The user can thereby recognize an abnormality occurred in the air-conditioning device 1 and a subsequent action, which improves user convenience.

[0088] The MP device 40 is set such that the number of indoor units that can be connected is more than or equal to two and less than or equal to eight. Thus, the amount of the refrigerant on the downstream side of the MP device 40 is larger than the amount of the refrigerant on the downstream side of the SP device 30 to which basically a single indoor unit is connected. Consequently, in the case where the refrigerant leaks out from any one of the indoor units connected to the MP device 40, the refrigerant recovery processing is executed without continuing operation, so that the amount of refrigerant leakage can be inhibited from increasing.

[0089] As described above, in the case where refrigerant leakage is detected in the indoor unit 204 connected to the SP device 30, the air-conditioning device 1 of the present embodiment closes the SPL control valve 31 and the SPG control valves 321, 322 to disconnect the indoor unit 204 from the refrigeration cycle system and stop operation of the indoor unit 204 and maintains the indoor units 201 to 203 other than the indoor unit 204 to be operable. On the other hand, in the case where refrigerant leakage is detected in the indoor units 201 to 203 connected to the MP device 40, the air-conditioning device 1 recovers the refrigerant from all of the indoor units 201 to 204, seals off the refrigerant on the outdoor unit 10 side, and stops and disallows subsequent operation of all of the indoor units 201 to 204. The multi-type air-conditioning device 1 can thereby ensure safety and reliability against leakage of the refrigerant while minimizing the number of valves.

[0090] Note that the number of the SP devices 30 and the number of the MP devices 40 provided for the multi-type air-conditioning device 1 are not limited to those described above. For example, the plurality of MP devices 40 and the plurality of SP devices 30 may be connected to form a single refrigeration cycle. Moreover, the number of indoor units connected to the SP device 30 and the number of indoor units connected to the MP device 40 are not limited to those described above. As described earlier, a model to which two indoor units can be connected, a model to which at most eight indoor units can be connected, and even a higher model can also be lined up as the MP device 40. Although it is presupposed that a single indoor unit is connected to the SP device 30 in principle, a plurality of indoor units can be connected in parallel to the pipes on the downstream side of the SP device 30. However, the indoor unit that can be connected to the SP device 30 is restricted in capability, and small-diameter tubes are used as the liquid-side refrigerant pipe 511 and the gas-side refrigerant pipe 52 located on the downstream side. Thus, an indoor unit of a high capability cannot be connected, and the amount of the refrigerant on the downstream side of the SP device 30 is small.

[0091] It is not necessary to provide the leakage detection sensors 24 for all of the indoor units. For example, in a case where a plurality of indoor units are installed in an identical space, at least one leakage detection sensor 24 should only be installed in the one space.

[0092] In the present embodiment, various types of processing such as the maintenance processing and the recovery processing when the refrigerant leaks out from an indoor unit of the air-conditioning device 1 are executed by the outdoor control unit 10, but the role of executing these types of processing may be assigned to any controller that is connected with a communication line and enables sharing of information. For example, if one of control units of indoor units, the MP device 40, or the SP device 30 is set as a master and control units of the other devices including the outdoor control unit 17 are set as slaves, the same processing as in the aforementioned control can be executed by an instruction from the control unit set as the master to the slave control units. Alternatively, a centralized management device that manages the air-conditioning device 1 as a whole may be connected to a communication line between the indoor control unit 25 and the outdoor control unit 17 in such a manner that communication can be made, and various types of processing when the refrigerant leaks out may be executed by this centralized management device.

[0093] An embodiment of the present invention has been described, but this embodiment has been presented as an example and is not intended to limit the scope of the invention. These novel embodiments can be carried out in other various forms, and various omissions, replacements, changes, and combinations of the respective components and controls can be made without departing from the spirit of the invention. These embodiments and their modifications are involved in the scope and spirit of the invention and involved in the invention recited in the claims and an equivalent range thereof.

Reference Signs List

[0094] 

1 multi-type air-conditioning device

10 outdoor unit

11 outdoor heat exchanger

14 compressor

171 maintenance processing unit

172 recovery processing unit

173 overall stop processing unit

174 setting processing unit

175 first report processing unit

176 second report processing unit

201, 202, 203, 304 indoor unit

21 indoor heat exchanger

24 leakage detection sensor

30 single-port shut-off valve device

31 single-port liquid-side control valve

321, 322 single-port gas control valve

40 multi-port shut-off valve device

411, 412, 421, 422, 431, 432 multi-port gas control valve

44 multi-port liquid-side control valve

Claims

1. A multi-type air-conditioning device capable of simultaneously performing cooling and heating operations, comprising:

an outdoor unit having an outdoor heat exchanger and a compressor;

a plurality of indoor units having indoor heat exchangers connected to the outdoor heat exchanger and the compressor, and leakage detection sensors capable of detecting leakage of a refrigerant;

a single-port shut-off valve device capable of controlling distribution of the refrigerant to a refrigerant distribution passage to which one of the indoor units is connected; and

a multi-port shut-off valve device capable of controlling distribution of the refrigerant to a plurality of refrigerant distribution passages to which a plurality of the indoor units are connected,

wherein the single-port shut-off valve device includes

a single-port liquid-side control valve provided for the refrigerant distribution passage in the single-port shut-off valve device to control distribution of the refrigerant in a liquid state, and

a single-port gas control valve provided for the refrigerant distribution passage in the single-port shut-off valve device to control distribution of the refrigerant in a gas state,

the multi-port shut-off valve device includes

a multi-port liquid-side control valve provided in common for the plurality of the indoor units in the multi-port shut-off valve device to control distribution of the refrigerant in the liquid state, and

a multi-port gas control valve provided for the refrigerant distribution passages in the multi-port shut-off valve device to control distribution of the refrigerant in the gas state,

the multi-type air-conditioning device comprising:

a maintenance processing unit capable of performing maintenance processing of, in a case where one of the leakage detection sensors provided for the one of the indoor units connected to the single-port shut-off valve device detects leakage of the refrigerant, closing the single-port liquid-side control valve and the single-port gas control valve corresponding to the one of the indoor units to stop operation of the one of the indoor units and maintaining the indoor units other than the one of the indoor units to be operable; and

a recovery processing unit capable of performing recovery processing of, in a case where any of the leakage detection sensors provided for the plurality of the indoor units connected to the multi-port shut-off valve device detects leakage of the refrigerant, causing the compressor to behave in a state where the multi-port liquid-side control valve and the single-port liquid-side control valve are closed to recover the refrigerant remaining in each of the indoor heat exchangers to a side of the compressor, closing all of the multi-port gas control valve and the single-port gas control valve after completion of recovery of the refrigerant, and stopping the compressor.

2. The multi-type air-conditioning device according to claim 1, further comprising

a setting processing unit capable of executing setting processing of, in a case where one of the leakage detection sensors provided for the one of the indoor units connected to the single-port shut-off valve device detects leakage of the refrigerant, setting which of the maintenance processing and the recovery processing is to be executed on a basis of a user input,

wherein the recovery processing unit executes the recovery processing in a case where the recovery processing is set in the setting processing in the case where the one of the leakage detection sensors provided for the one of the indoor units connected to the single-port shut-off valve device detects leakage of the refrigerant.

3. The multi-type air-conditioning device according to claim 1 or 2, further comprising
an overall stop processing unit capable of executing overall stop processing of disallowing operation of all of the indoor units after completion of the recovery processing.

4. The multi-type air-conditioning device according to claim 1 or 2, further comprising
a first report processing unit capable of executing first report processing of, in a case where the maintenance processing is executed, reporting that one of the indoor units from which the refrigerant has leaked out is not operable, but the indoor units other than the one of the indoor unit from which the refrigerant has leaked out can continue operation.

5. The multi-type air-conditioning device according to claim 3, further comprising
a second report processing unit capable of executing second report processing of, in a case where the overall stop processing is executed, reporting that none of the indoor units is operable.

6. The multi-type air-conditioning device according to claim 1,
wherein the number of the indoor units that can be connected to the multi-port shut-off valve device is set to more than or equal to two and less than or equal to eight.

Drawing