Air conditioning system and evacuation procedures in an air conditioning system

Abstract

An air conditioning device is capable of performing simultaneous cooling and heating operations and comprises an outdoor unit, a plurality of indoor units, and a distribution unit.The distribution unit has the following: a first path formed by a first line and configured to allow the refrigerant to flow from the plurality of indoor units to the distribution unit; a second path formed by a second line and configured to allow the refrigerant to flow from the distribution unit to the plurality of indoor units; a third path formed by a third line and configured to allow the refrigerant to flow from the plurality of indoor units to the distribution unit; and a fourth path formed by a fourth line and configured to allow the refrigerant to flow from the distribution unit to the plurality of indoor units.The transfer unit comprises the following: a first opening and closing device located in the first path and configured to individually block or allow each flow of refrigerant flowing from a corresponding indoor unit towards the transfer unit, and a second opening and closing device located in the second path and configured to individually block or allow each flow of refrigerant flowing from the transfer unit towards the corresponding indoor unit.The transfer unit comprises the following: a first shut-off device configured to open in a non-powered state, allowing refrigerant flow in the fourth path, and to close in a powered state, blocking refrigerant flow in the fourth path; and an opening and closing device for evacuation configured to open in a non-powered state, allowing fluid flow in at least one of the first to fourth paths, and to close in a powered state, blocking refrigerant flow in at least one of the paths.

Description

Technical field

[0001] The present invention discloses an air conditioning device capable of simultaneous cooling and heating, as well as an evacuation method in the air conditioning device. State of the art

[0002] In an air conditioning system, a refrigerant circuit is formed, for example, by connecting an outdoor unit, which is a heat source unit located outside a building, to an indoor unit located inside the building via a duct, and allowing a refrigerant to circulate within it. The air conditioning system heats air by using heat that is absorbed by the refrigerant, or it cools air by removing heat using the refrigerant, thus heating or cooling an air-conditioned space.

[0003] Generally, when installing an air conditioning unit, refrigerant is charged into the outdoor unit, but no refrigerant is charged into an indoor unit or a distribution unit. When an air conditioning unit is installed, the installation is carried out in the following sequence: connecting a line, evacuating, opening an operating valve on the outdoor unit, and charging additional refrigerant to prevent air from entering the refrigerant circuit. The evacuation described here is a process for removing air from a line that forms the refrigerant circuit using a vacuum pump. The simple process of evacuation involves connecting the vacuum pump to a service port near the operating valve located in the outdoor unit and drawing out the air using the vacuum pump.When installing an air conditioning system, evacuation is carried out from a service port located in the outdoor unit. Therefore, for design reasons, both the distribution unit and the indoor unit of the air conditioning system must have a path that allows evacuation from the outdoor unit.

[0004] For safety reasons, a conventional air conditioning device is also equipped with a shut-off device that blocks the flow of refrigerant in the refrigerant circuit if a refrigerant leak occurs (see, for example, patent reference 1). The shut-off device in patent reference 1 is configured to block the flow of refrigerant in one direction, from an outdoor unit to an indoor unit, thus preventing the refrigerant from remaining in an indoor space. Bibliography Patent literature

[0005] Patent Literature 1: Japanese Unexamined Patent Application Publication JP 2018 - 169 072 A Summary of the invention: Technical problem

[0006] Power is supplied to the air conditioning unit after the installation of all electrical circuits and refrigerant lines is complete and preparations for trial operation have been finished. Since evacuation takes place during the installation of the refrigerant lines, all components forming the refrigerant circuit are in a de-energized state during evacuation.

[0007] In the air conditioning device according to patent literature 1, the shut-off device is designed as a valve that is closed in a state not supplied with energy. Consequently, in the air conditioning device according to patent literature 1, during evacuation, the refrigerant circuit is blocked in the area where the shut-off device is installed, and therefore no evacuation path from the outdoor unit can be guaranteed. As a result, the air conditioning device cannot be easily installed.

[0008] Although the air conditioning device described in patent literature 1 has a simple configuration with a single indoor unit, there is an air conditioning device that has multiple indoor units and is capable of performing simultaneous cooling and heating operations. Such an air conditioning device capable of performing simultaneous cooling and heating operations has an outdoor unit, multiple indoor units, and a distribution unit that has multiple valves and is configured to divide the refrigerant into multiple flow paths.Since the distribution unit in the air conditioning device, which is capable of performing simultaneous cooling and heating operations, has a plurality of valves, the following applies: If a shut-off device for a refrigerant leak is arranged in the air conditioning device, ensuring a path for evacuation becomes more difficult, and consequently, it has poor designability.

[0009] The present invention was designed to solve the above-mentioned problems and has the objective of providing an air conditioning device capable of simultaneous cooling and heating and which has improved constructability even when a refrigerant leakage shutdown device is present, as well as providing an evacuation method for the air conditioning device. Solution to the problem

[0010] An air conditioning device according to an embodiment of the present invention is capable of performing simultaneous cooling and heating operations and comprises the following: an outdoor unit with a compressor, an outdoor heat exchanger configured for exchanging heat between outdoor air and refrigerant, and a flow switching device; a plurality of indoor units, each comprising an indoor heat exchanger configured for exchanging heat between the air to be conditioned and the refrigerant; a distribution unit arranged between the outdoor unit and the plurality of indoor units and configured to switch the flow of the refrigerant supplied from the outdoor unit to the indoor units; and a refrigerant circuit formed by the outdoor unit,The majority of indoor units and the distribution unit are connected by means of a refrigerant line.

[0011] The distribution unit comprises the following: a first path formed by a first line and configured to allow refrigerant to flow from the plurality of indoor units to the distribution unit; a first opening and closing device located in the first path and configured to individually block or allow each flow of refrigerant flowing from a corresponding plurality of indoor units towards the distribution unit; a second path formed by a second line and configured to allow refrigerant to flow from the distribution unit to the plurality of indoor units; and a second opening and closing device located in the second path and configured to individually block or allow each flow of refrigerant.which is divided from the distribution unit towards a corresponding plurality of indoor units, a third path formed by a third line and configured to allow the refrigerant to flow from the plurality of indoor units to the distribution unit, a fourth path formed by a fourth line and configured to allow the refrigerant to flow from the distribution unit to the plurality of indoor units, a first shut-off device configured to open in a non-powered state, thus allowing refrigerant to flow in the fourth path, and to close in a powered state, thus blocking refrigerant flow in the fourth path, and an evacuation opening and closing device configured tothat it opens in a state not subjected to energy, so that it allows a flow of the refrigerant in at least one of the first path, the second path, the third path and the fourth path, and closes in a state subjected to energy, so that it blocks a flow of the refrigerant in at least one of the paths.

[0012] An evacuation method for an air conditioning device according to an embodiment of the present invention is a method for evacuating a refrigerant circuit of the aforementioned air conditioning device. The evacuation is carried out by operating a vacuum pump connected to a service port located in the refrigerant circuit, in a state where the air conditioning device is not powered. Advantageous effects of the invention

[0013] In the air conditioning device according to one embodiment of the present invention, a second opening and closing device is arranged in the second path, which is a path for the flow of refrigerant from the distribution unit to the plurality of indoor units, and a first shut-off device is arranged in the fourth path, which is a path for the flow of refrigerant from the distribution unit to the plurality of indoor units. Furthermore, the air conditioning device is provided with an opening and closing device for evacuation, which is configured to open in a non-powered state and allow refrigerant flow in at least one of the first path, the second path, the third path, and a fourth path, and is configured to close in a powered state and block refrigerant flow in at least one of the paths.

[0014] If a refrigerant leak occurs, the air conditioning unit closes the second opening and closing device, the first shut-off device, and the evacuation opening and closing device, thus blocking the flow of refrigerant from the outdoor unit to the indoor units. Furthermore, since the evacuation opening and closing device opens in a non-powered state, the air conditioning unit allows fluid flow in at least one of the first, second, third, and fourth paths, thereby ensuring an evacuation path. Consequently, the design of an air conditioning unit capable of simultaneous cooling and heating operation can be improved while incorporating a refrigerant leak blocking function. Brief description of the drawings Fig. Figure 1 is a schematic diagram illustrating an example of the configuration of an air conditioning device according to embodiment 1. Fig. Figure 2 is a schematic diagram illustrating an example of refrigerant flows in a cooling-only operating mode in the air conditioning device according to embodiment 1. Fig. Figure 3 is a schematic diagram illustrating an example of refrigerant flows in a cooling main operating mode in the air conditioning device according to embodiment 1. Fig. Figure 4 is a schematic diagram illustrating an example of refrigerant flows in a heating main operating mode in the air conditioning device according to embodiment 1. Fig. Figure 5 is a schematic diagram illustrating an example of refrigerant flows in a heat-only operating mode in the air conditioning device according to embodiment 1. Fig. Figure 6 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in the air conditioning device according to embodiment 1. Fig. Figure 7 is a schematic diagram illustrating an example of airflows during evacuation in the air conditioning device according to embodiment 1. Fig. Figure 8 is a schematic diagram illustrating an example of a method for connecting an external circuit 76 involved in the evacuation in the air conditioning device according to embodiment 1. Fig. Figure 9 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device according to embodiment 2. Fig. Figure 10 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device according to embodiment 3. Fig. Figure 11 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device according to embodiment 4. Fig. Figure 12 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device according to embodiment 5. Fig. Figure 13 is a schematic configuration diagram of a solenoid valve with an opening in the air conditioning device according to embodiment 5. Fig. Figure 14 is an operating diagram of the solenoid valve with opening in the air conditioning device according to embodiment 5 and shows an open state of the solenoid valve with opening. Fig. Figure 15 is an operating diagram of the solenoid valve with opening in the air conditioning device according to embodiment 5 and shows a closed state of the solenoid valve with opening. Fig. Figure 16 is a schematic diagram illustrating an example of airflows during evacuation in the air conditioning device according to embodiment 5. Description of embodiments

[0015] With reference to the drawings, embodiments of the present invention are described below. In the drawings, the same or corresponding components are designated with the same reference numerals, and their descriptions are omitted or simplified where appropriate. With respect to the configuration described in each drawing, the shape, size, and arrangement can be suitably modified within the scope of the present invention. Design 1 Structural components

[0016] Fig. Figure 1 is a schematic diagram illustrating an example of the configuration of an air conditioning device 100 according to embodiment 1. The air conditioning device 100 has an outdoor unit 81, a distribution unit 82, and a plurality of indoor units 83a, 83b, and 83c. The air conditioning device 100 is a multi-split type air conditioning device capable of performing simultaneous cooling and heating operation, in which cooling and heating are carried out simultaneously by the plurality of indoor units 83a, 83b, and 83c. Although the case of three indoor units 83 is described here, the number of indoor units 83 can be two, four, or more.

[0017] In the air conditioning device 100, the distribution unit 82 is arranged between the outdoor unit 81 and the multiple indoor units 83a, 83b and 83c. The multiple indoor units 83a, 83b and 83c are connected in parallel to the distribution unit 82.

[0018] The outdoor unit 81 and the distribution unit 82 are connected by a high-pressure line 7 and a low-pressure line 8. Refrigerant flows at high pressure in the high-pressure line 7 from the outdoor unit 81 to the distribution unit 82. The high-pressure line 7 is equipped with an actuating valve 4 on the high-pressure side and a high-pressure service port 71. Refrigerant flows at low pressure in the low-pressure line 8 from the distribution unit 82 to the outdoor unit 81. The low-pressure line 8 is equipped with an actuating valve 5 on the low-pressure side and a low-pressure service port 72. Here, the pressure level is not defined relative to a reference pressure (value) but is expressed as a relative level.

[0019] The distribution unit 82 and the indoor unit 83a are connected by means of a liquid branch line 42a and a gas branch line 43a. The distribution unit 82 and the indoor unit 83b are connected by means of a liquid branch line 42b and a gas branch line 43b. The distribution unit 82 and the indoor unit 83c are connected by means of a liquid branch line 42c and a gas branch line 43c. In the air conditioning device 100, the outdoor unit 81, the distribution unit 82 and the majority of indoor units 83a, 83b and 83c are connected by means of refrigerant lines, which include the high pressure line 7, the low pressure line 8, the liquid branch lines 42a, 42b and 42c, and the gas branch lines 43a, 43b and 43c, so that a refrigerant circuit A is formed through which refrigerant circulates.

[0020] In the following, the suffixes a, b, and c are omitted where, for example, indoor units 83a, 83b, and 83c do not require further differentiation or specification. Similarly, in cases where facilities different from indoor units 83 do not require further differentiation or specification, the suffixes a, b, and c are occasionally omitted. Outdoor unit 81

[0021] The outdoor unit 81 comprises the following: a compressor 1, a flow switching device 2, an outdoor heat exchanger 3, the actuating valve 4 on the high-pressure side, the high-pressure line service connection 71, the actuating valve 5 on the low-pressure side, the low-pressure line service connection 72 and a check valve block 6. Compressor 1

[0022] Compressor 1 is configured to draw in refrigerant in a low temperature / low pressure condition, compress the drawn-in refrigerant into a high temperature / high pressure condition, and discharge the refrigerant in a high temperature / high pressure condition. Flow switching device 2

[0023] The flow switching device 2 is configured to reverse the direction of refrigerant flow in refrigerant circuit A. The flow switching device 2 is designed as a four-way valve. However, the flow switching device 2 is not limited to a four-way valve. It can have any configuration as long as it allows the refrigerant flow direction in refrigerant circuit A to be reversed. For example, the flow switching device 2 could be a combination of a solenoid valve and a check valve, provided a similar effect is achieved. The configuration of the flow switching device 2 is not restricted. Outdoor heat exchanger 3

[0024] The outdoor heat exchanger 3, for example, is a tube-fin type heat exchanger of a transversely finned system formed with a heat transfer tube and several fins, and is configured to exchange heat between the outdoor air and the refrigerant so that the heat is dissipated. Actuating valve 4 on the high-pressure side

[0025] The actuating valve 4 on the high-pressure side is, for example, designed as a two-way valve capable of switching between open and closed. The actuating valve 4 on the high-pressure side is located in the high-pressure line 7. The actuating valve 4 on the high-pressure side is configured to be opened manually during the installation of the air conditioning unit 100, as described later, and remains open at all times unless manually closed for repair or other reasons. High-pressure line service connection 71

[0026] The high-pressure line service port 71 is a port to which a vacuum pump is connected during evacuation or to which a refrigerant cylinder or bottle is connected when refrigerant is being charged. The high-pressure line service port 71 is located in a flow passage that branches off from the high-pressure line 7 on the downstream side of the actuating valve 4 on the high-pressure side. Regardless of the open / closed state of the high-pressure line service port 71, refrigerant can flow between the actuating valve 4 on the high-pressure side and the high-pressure line 7. Actuating valve 5 on the low-pressure side

[0027] The actuating valve 5 on the low-pressure side is, for example, designed as a two-way valve capable of switching between open and closed. The actuating valve 5 on the low-pressure side is located in the low-pressure line 8. The actuating valve 5 on the low-pressure side is configured to be opened manually during the installation of the air conditioning unit 100, as described later, and it remains open at all times unless it is manually closed for repair or other reasons. Low-pressure line service connection 72

[0028] The low-pressure line service port 72 is a port to which a vacuum pump is connected during evacuation or to which a refrigerant cylinder or bottle is connected when refrigerant is being charged. The low-pressure line service port 72 is located in a flow passage that branches off from the low-pressure line 8 on the upstream side of the actuating valve 5 on the low-pressure side. Regardless of the open / closed state of the low-pressure line service port 72, refrigerant can flow between the actuating valve 5 on the low-pressure side and the low-pressure line 8. Check valve block 6

[0029] The check valve block 6 consists of four check valves and is arranged to control the refrigerant flow direction. The check valve block 6 comprises four check valves 6a, 6b, 6c, and 6d. Check valve 6a is configured to allow refrigerant to flow from the actuating valve 5 on the low-pressure side towards the flow switching device 2, but not to allow flow in the opposite direction.

[0030] The check valve 6b is configured to allow refrigerant to flow from the flow changeover device 2 towards the actuating valve 4 on the high-pressure side, but not to allow flow in the opposite direction. The check valve 6c is configured to allow refrigerant to flow from the actuating valve 5 on the low-pressure side towards the outdoor heat exchanger 3, but not to allow flow in the opposite direction. The check valve 6d is configured to allow refrigerant to flow from the outdoor heat exchanger 3 towards the actuating valve 4 on the high-pressure side, but not to allow flow in the opposite direction.

[0031] With this check valve block 6 in the outdoor unit 81, the refrigerant flows in one direction from the transfer unit 82 towards the outdoor unit 81 in the low-pressure line 8 and flows in one direction from the outdoor unit 81 towards the transfer unit 82 in the high-pressure line 7, regardless of the operating mode.

[0032] The outdoor unit 81 is configured to switch between two flow directions according to the state of the flow switching device 2. When the flow switching device 2 is in a first state, the structural components of the outdoor unit 81 are connected by lines so that refrigerant flows through them in the following sequence: actuating valve 5 on the low-pressure side, check valve 6a, flow switching device 2, compressor 1, flow switching device 2, outdoor heat exchanger 3, check valve 6d and actuating valve 4 on the high-pressure side.

[0033] When the flow switching device 2 is in a second state, the structural components of the outdoor unit 81 are connected by lines so that refrigerant flows through them in the following order: actuating valve 5 on the low-pressure side, check valve 6c, outdoor heat exchanger 3, flow switching device 2, compressor 1, flow switching device 2, check valve 6b and actuating valve 4 on the high-pressure side. Forwarding unit 82

[0034] The distribution unit 82 is arranged between the outdoor unit 81 and the indoor units 83 and is configured to switch the refrigerant flows supplied from the outdoor unit 81 to the indoor units 83. For example, the distribution unit 82 is installed indoors and is configured to control the refrigerant flow according to the operations required in the indoor units 83. The distribution unit 82 comprises: a first branching unit 17, a second branching unit 18, a first flow control device 19, a second flow control device 20, an inlet branching unit 22, and an outlet merging unit 23. First branching unit 17

[0035] The first branch unit 17 is a section configured to transfer the refrigerant between the outdoor unit 81 and a gas side of the majority of indoor units 83. The first branch unit 17 comprises: a first path 13, a first opening and closing device 300, a battery 600, a second path 14, and a second opening and closing device 310.

[0036] The first path 13 is a path in which the refrigerant flows from the plurality of indoor units 83 towards the distribution unit 82, and it is formed by a first line 10. The first line 10 is a low-pressure line in which the refrigerant flows at low pressure. One end of the first line 10 is connected to the low-pressure line 8, and the other end branches into three branches, corresponding to the number of indoor units 83. The other end of the first line 10 branches according to the plurality of indoor units 83.

[0037] More precisely: The first line 10 has a main line 10a and branch lines 10b, 10c, and 10d. The branch lines 10b, 10c, and 10d are connected to the respective gas branch lines 43a, 43b, and 43c, each corresponding to one of the indoor units 83a, 83b, and 83c. The branch lines 10b, 10c, and 10d are each connected to the corresponding branch line 9b, 9c, or 9d, which is a second line 9, as described later, and corresponds to one of the indoor units 83a, 83b, and 83c, which are to be joined to form a union unit, and the union unit is connected to the corresponding gas branch line 43a, 43b, or 43c.

[0038] The first opening and closing device 300 is located in the first line 10, which forms the first path 13, and is configured to individually block or allow the refrigerant to pass through as it flows from each indoor unit 83 toward the transfer unit 82. The first opening and closing device 300 has first opening and closing units 30a, 30b, and 30c, which are arranged corresponding to the indoor units 83a, 83b, and 83c. Each first opening and closing unit 30 is configured to be open when not powered and to be closed when powered, thus shutting off the refrigerant flow.

[0039] Although in Fig. 1. The configuration is not limited to the first opening and closing device 300 being provided with a single first opening and closing unit 30 for each indoor unit 83. The first opening and closing device 300 can be provided with a common first opening and closing unit 30 for the indoor units 83, which always operate in the same operating mode.

[0040] Each first opening and closing unit 30 is a switching valve and is configured as a solenoid valve. Embodiment 1 has a configuration in which evacuation is carried out from the first path 13, as described below, and the first opening and closing unit 30, which is arranged in the first path 13, is configured as a solenoid valve that maintains an open state by means of a spring or similar device when no energy is supplied. The first opening and closing unit 30 is a pilot-type, auxiliary-control, or pilot-type solenoid valve configured to induce the refrigerant pressure by actuating a pilot valve by means of an electromagnetic force, so that it actuates the main valve by means of a refrigerant pressure differential.

[0041] In the example shown in the drawing, the first opening and closing unit 30 is formed by a single solenoid valve, but the configuration is not limited to this. The first opening and closing unit 30 can be formed by a plurality of solenoid valves connected in parallel, thus reducing pressure losses in the solenoid valves. Furthermore, the first opening and closing unit 30 can be formed by a plurality of solenoid valves connected in series, as described in a subsequent embodiment, thus reducing the amount of refrigerant leakage.

[0042] Meanwhile, energy is supplied to the air conditioning unit 100 only after the installation of all electrical circuits and refrigerant lines is complete and preparations for trial operation have been finished. During the evacuation carried out during the installation of the refrigerant lines, all equipment contained in refrigerant circuit A is therefore in a de-energized state. Although the evacuation can be carried out from the first path 13, the second path 14, a third path 15, or a fourth path 16, embodiment 1 is configured such that the evacuation is carried out from the first path 13.

[0043] For this reason, the first opening and closing device 300 also serves as an evacuation opening and closing device S, which can provide an evacuation path while all equipment is in a de-energized state. The evacuation opening and closing device S is configured to open in a de-energized state, allowing air as a fluid to flow into the first path 13, and to close in a energized state, blocking the flow of refrigerant. Because the first opening and closing device 300 also serves as an evacuation opening and closing device S, the air conditioning device 100 can provide an evacuation path even when all equipment is in a de-energized state.

[0044] Battery 600 is a power source for operating the first opening and closing device 300 in the event of a power failure. Battery 600 is designed to prevent refrigerant leakage by operating the first opening and closing device 300, even when no power is supplied to the air conditioning unit 100. The first opening and closing device 300 is configured to open in a non-powered state, as described above, and consequently remains open in the event of a power failure. In this case, the air conditioning unit 100 cannot prevent refrigerant leakage from the indoor units 83 in the event of a power failure.With the battery 600, which is connected to the first opening and closing device 300, the air conditioning unit 100 can prevent refrigerant leakage from the indoor units 83 in the event of a power malfunction, thus improving safety. The battery 600 includes batteries 60a, 60b, and 60c for the respective first opening and closing units 30a, 30b, and 30c.

[0045] The second path 14 is a path in which the refrigerant flows from the distribution unit 82 towards the majority of indoor units 83, and it is formed by the second line 9. The second line 9 is a high-pressure line in which the refrigerant flows under high pressure. One end of the second line 9 is connected to the high-pressure line 7, and the other end branches into three branches, corresponding to the number of indoor units 83.

[0046] More precisely: The second line 9 has a main line 9a and branch lines 9b, 9c, and 9d. Branch lines 9b, 9c, and 9d are connected to the respective gas branch lines 43a, 43b, and 43c, each corresponding to one of the indoor units 83a, 83b, and 83. Branch lines 9b, 9c, and 9d are each connected to the corresponding branch line 10b, 10c, or 10d, which is the first line 10 and corresponds to one of the indoor units 83a, 83b, and 83c to be connected, thus forming a union unit, and the union unit is connected to the corresponding gas branch line 43a, 43b, or 43c.

[0047] The second opening and closing device 310 is arranged in the second line 9, which forms the second path 14, and is configured to individually block or allow each split stream of refrigerant as it flows from the distribution unit 82 to each indoor unit 83, and to block the refrigerant in the event of a leak. The second opening and closing device 310 has second opening and closing units 31a, 31b, and 31c, which are arranged corresponding to the indoor units 83a, 83b, and 83c.

[0048] The second opening and closing device 310 is provided with a second opening and closing unit 31 for each interior unit 83. The second opening and closing device 310 is not limited to the configuration in which a second opening and closing unit 31 is arranged for each of the interior units 83. The second opening and closing device 310 can also be provided with a common second opening and closing unit 31 for the interior units 83, which always operate in the same operating mode.

[0049] The second opening and closing unit 31 is a switching valve and is designed as a solenoid valve. In the example shown in the drawing, the second opening and closing unit 31 is formed by a single solenoid valve, but the configuration is not limited to this. The second opening and closing unit 31 can be formed by a plurality of solenoid valves connected in parallel, thus reducing pressure losses in the solenoid valves. Furthermore, the second opening and closing unit 31 can be formed by a plurality of solenoid valves connected in series, as described in a subsequent embodiment, thus reducing the amount of refrigerant leakage. Second branching unit 18

[0050] The second branch unit 18 is a section configured to transfer the refrigerant between the outdoor unit 81 and a liquid side of the majority of indoor units 83. The second branch unit 18 comprises: the third path 15, a third opening and closing device 320, a fourth path 16, a fourth opening and closing device 330, and a battery 61.

[0051] The third path 15 is a path in which the refrigerant flows from the plurality of indoor units 83 towards the distribution unit 82, and it is formed by a third line 12. The third line 12 is a medium-pressure line in which the refrigerant flows at a medium pressure, where medium pressure is a pressure level between high and low pressure. One end of the third line 12 is connected to a main line 11a of a fourth line 11, as described later, and the other end of the third line 12 branches into the same number of branches as the number of indoor units 83, which is three.

[0052] More precisely: The third line 12 has a main line 12a and branch lines 12b, 12c, and 12d. One end of the main line 12a is connected to the main line 11a of the fourth line 11. The other end of the main line 12a is connected to one end of each branch line 12b, 12c, and 12d. The other ends of the branch lines 12b, 12c, and 12d are each connected to the corresponding branch line 11b, 11c, or 11d contained within the fourth line 11, as described later, and correspond to one of the internal units 83a, 83b, and 83c to be joined, thus forming a union unit, and the union unit is connected to the corresponding liquid branch line 42a, 42b, or 42c.

[0053] The third opening and closing device 320 is located in the third line 12, which forms the third path 15, and is configured to individually block or allow the refrigerant flowing from each indoor unit 83 toward the distribution unit 82. The third opening and closing device 320 includes third opening and closing units 32a, 32b, and 32c, which are arranged corresponding to the indoor units 83a, 83b, and 83c. Although in the example shown in the drawing the third opening and closing units 32 are located in the branch lines 12b, 12c, and 12d, each branching off from the third line 12, the configuration is not limited to this. The third opening and closing device 320 can be provided with a common third opening and closing unit 32 for the indoor units 83, which always operate in the same mode.

[0054] Each of the third opening and closing units 32 is configured as a valve such that it allows and blocks the refrigerant flowing from the corresponding indoor unit 83 to the distribution unit 82. In embodiment 1, the third opening and closing units 32 are configured as check valves. Each check valve is configured to allow a refrigerant flow from the indoor unit 83 to the distribution unit 82 and blocks a flow in the opposite direction. Although the third opening and closing units 32 are configured as check valves in embodiment 1, the configuration is not limited to this.

[0055] Each of the third opening and closing units 32 can be any device as long as the flow of the refrigerant flowing from the third line 12 towards a liquid branch line 42 can be blocked during operation, and it can also use a solenoid valve. The third opening and closing unit 32 can be formed by a plurality of check valves, thus reducing pressure losses in the check valves. Furthermore, the third opening and closing unit 32 can be configured as an electronic expansion valve, as described in a following embodiment.

[0056] The fourth path 16 is a path in which the refrigerant flows from the distribution unit 82 towards the plurality of indoor units 83, and it is formed by the fourth line 11. The fourth line 11 is a medium-pressure line in which the refrigerant flows at a medium pressure. Medium pressure is a pressure level between high and low pressure. One end of the fourth line 11 is connected to the inlet branch unit 22, and the other end branches into three branches, which is the same number as the number of indoor units 83. The other end of the fourth line 11 branches according to the plurality of indoor units 83.

[0057] More precisely: The fourth conduit 11 comprises the main conduit 11a and branch conduits 11b, 11c, and 11d. One end of the main conduit 11a is connected to the inlet branch unit 22. The other end of the main conduit 11a is connected to one end of each branch conduit 11b, 11c, and 11d. The other ends of the branch conduits 11b, 11c, and 11d are each connected to the corresponding branch conduit 12b, 12c, or 12d contained within the third conduit 12, which corresponds to one of the indoor units 83a, 83b, and 83c to be connected, thus forming a union unit. The union unit is then connected to the corresponding liquid branch conduit 42a, 42b, or 42c.

[0058] The fourth opening and closing device 330 is located in the fourth line 11, which forms the fourth path 16, and is configured to individually allow the refrigerant flowing from the distribution unit 82 toward each indoor unit 83 to pass through, and to individually block the opposite flow. The fourth opening and closing device 330 has fourth opening and closing units 33a, 33b, and 33c, which are arranged corresponding to the indoor units 83a, 83b, and 83c. Although in the example shown in the drawing the fourth opening and closing units 33 are located in the branch lines 11b, 11c, and 11d, each branching off from the fourth line 11, the configuration is not limited to this. The fourth opening and closing device 330 can be provided with a common fourth opening and closing unit 33 for the indoor units 83, which always operate in the same mode.

[0059] Each of the fourth opening and closing units 33 is configured as a valve such that it allows and blocks the refrigerant flowing from the distribution unit 82 to the corresponding indoor unit 83. In embodiment 1, the fourth opening and closing units 33 are configured as check valves. Each check valve is configured to allow a refrigerant flow from the distribution unit 82 to the indoor unit 83 and blocks a flow in the opposite direction. Although the fourth opening and closing units 33 are configured as check valves in embodiment 1, the configuration is not limited to this.

[0060] Each fourth opening and closing unit 33 can be any device, as long as the flow of the refrigerant flowing from the liquid branch line 42 towards the fourth line 11 can be blocked during operation, and it can also use a solenoid valve. The fourth opening and closing unit 33 can be formed by a plurality of check valves, thus reducing pressure losses in the check valves. Furthermore, the fourth opening and closing unit 33 can be configured as an electronic expansion valve, as described in a subsequent embodiment.

[0061] A first shut-off device 21 is configured to open in a non-powered state, allowing refrigerant to flow in the fourth path 16, and to close in a power-energized state, blocking the refrigerant flow in the fourth path 16. The first shut-off device 21 is a switch-on / switch-off valve that is held open by a spring or similar device when no power is supplied and is designed as a solenoid valve. The first shut-off device 21 is located in the main line 11a of the fourth line 11. From a cost perspective, it is preferred that the first shut-off device 21 be installed in the main line 11a of the fourth line 11, as shown in the drawing.From the point of view of pressure losses, however, the first switching device 21 can also be installed in each of the branch lines 11b, 11c and 11d of the fourth line 11, and the fourth opening and closing units 33a, 33b and 33c can be omitted.

[0062] The first shutdown device 21 is connected to the battery 61, which serves as a power source for operating the first shutdown device 21 in the event of a power failure. The battery 61 is arranged to prevent refrigerant leakage by operating the first shutdown device 21, even when no power is supplied to the air conditioning unit 100. With the battery 61 connected to the first shutdown device 21, the air conditioning unit 100 can prevent refrigerant leakage in the event of a power failure, thus improving safety.

[0063] Although in the example according to the drawing the first shut-off device 21 is designed as a single solenoid valve arranged in the main line 11a of the fourth line 11, the first shut-off device 21 can also be designed by a plurality of solenoid valves in the branch lines 11b, 11c and 11d of the fourth line 11, as described above.

[0064] This means that the first shut-off device 21 can be configured as a plurality of solenoid valves connected in series with the respective fourth opening and closing units 33a, 33b, and 33c in the branch lines 11b, 11c, and 11d. The air conditioning device with this configuration can achieve the same effect as the one described above. With this configuration, the air conditioning device also has the effect that only the indoor unit 83 with a refrigerant leak can be blocked, while the other indoor units 83, which do not have a refrigerant leak, can continue cooling or heating. First flow control device 19

[0065] The first flow control device 19 is arranged in a line that branches off from a point between the second flow control device 20 and the first shut-off device 21 in the main line 11a of the fourth line 11 and forms a flow passage towards the outlet merging unit 23. The first flow control device 19 is designed as a solenoid valve or an expansion valve configured to be driven, for example, by a stepper motor. Second flow control device 20

[0066] The second flow control device 20 is arranged between the inlet branch unit 22 and the first shut-off device 21 in the main line 11a of the fourth line 11. The second flow control device 20 is designed as a solenoid valve or an expansion valve, configured to be driven, for example, by a stepper motor. Inlet branching unit 22

[0067] The inlet branch unit 22 is a unit configured to divide the refrigerant flowing from the high-pressure line 7 into the transfer unit 82, into the side of the first branch unit 17 and the side of the second branch unit 18. Outlet junction unit 23

[0068] The outlet merging unit 23 is a unit configured to merge the refrigerant flowing from the first branch unit 17 towards the outdoor unit 81 and the refrigerant flowing from the second branch unit 18 towards the outdoor unit 81. Indoor unit 83

[0069] Indoor unit 83a includes a pressure reducing device 40a and an indoor heat exchanger 41a. Indoor unit 83b includes a pressure reducing device 40b and an indoor heat exchanger 41b. Indoor unit 83c includes a pressure reducing device 40c and an indoor heat exchanger 41c. Pressure reduction device 40

[0070] The pressure reducing devices 40 are each configured to control the volume flow of the refrigerant, and the degree of opening can be set to be variable. Each of the pressure reducing devices 40a, 40b, and 40c is designed as an electronic expansion valve. The pressure reducing device 40 is connected to the distribution unit 82 via the liquid branch line 42. Interior heat exchanger 41

[0071] Each indoor heat exchanger 41 is a tubular-finned heat exchanger of a transversely finned system, formed, for example, with a heat transfer tube and several fins, and is configured to exchange heat between the indoor air in the air-conditioned space and the refrigerant. The indoor heat exchanger 41 is connected to the distribution unit 82 via the corresponding gas branch line 43. Controls 50, 51 and 52

[0072] The air conditioning unit 100 has a control unit 50 installed in the outdoor unit 81 and a control unit 51 installed in the distribution unit 82. The air conditioning unit 100 also has a control unit 52a installed in the indoor unit 83a, a control unit 52b installed in the indoor unit 83b, and a control unit 52c installed in the indoor unit 83c. Although in Fig. 1. The configuration is not limited to the fact that the controls 52a, 52b and 52c are arranged separately. For example, in the air conditioning device 100, the controls 52a, 52b and 52c can be integrated in an optional combination and installed in the outdoor unit 81 or the distribution unit 82, or they can be installed in any or some of the indoor units 83.

[0073] A processing circuit of each of the controllers 50, 51 and 52 is designed as dedicated hardware or a central processing unit (CPU; also referred to as central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer or processor) configured to execute a program stored in memory.

[0074] If the processing circuit of the controller 50, 51, or 52 is dedicated hardware, the processing circuit corresponds, for example, to a single circuit, a composite circuit, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a combination of these circuits. In each controller 50, 51, and 52, the functional units implemented by the processing circuit can each be achieved by individual hardware elements, or they can be achieved by a single hardware element.

[0075] If the processing circuit of the controller 50, 51, or 52 is the CPU, then each function performed by the processing circuit is achieved by software, firmware, or a combination of both. The software or firmware is described as a program and is stored in a memory unit. The CPU is configured to read and execute the program stored in the memory unit, thereby achieving each of the processing circuit's functions. Some of the processing circuit's functions can be achieved by dedicated hardware, and others can be achieved by software or firmware. Operating modes

[0076] The air conditioning unit 100 can perform air conditioning using a refrigeration circuit by circulating a refrigerant. Each indoor unit 83 can select one operating mode from at least two, cooling and heating, according to a user instruction. The outdoor unit 81 can select one operating mode from several, as described below, by switching the flow switching device 2 according to the ratio between the total cooling load and the total heating load of the indoor units 83.

[0077] The following operating modes can be selected: a cooling-only mode, in which all indoor units perform cooling; a heating-only mode, in which all indoor units perform heating; or a mixed mode, in which cooling and heating occur simultaneously. The mixed mode includes a primary cooling mode, in which there is a high cooling load, and a primary heating mode, in which there is a high heating load. In this case, the cooling-to-heating load ratio, when switching between the primary cooling and heating modes, is approximately one, but the load ratio can be set to any desired ratio.

[0078] The air conditioning device 100 is configured to operate the first opening and closing units 30, which are arranged in the first path 13, and the second opening and closing units 31, which are arranged in the second path 14 in the distribution unit 82, according to the operating modes of the outdoor unit 81 and the indoor units 83. The air conditioning device 100 achieves simultaneous cooling and heating operation by changing the flow direction of the refrigerant in each indoor unit 83 by individually operating the corresponding first opening and closing unit 30 and the corresponding second opening and closing unit 31 according to the indoor unit 83. Cooling-only operating mode

[0079] Fig. Figure 2 is a schematic diagram illustrating an example of the refrigerant flows in the cooling-only operating mode in the air conditioning device 100 according to embodiment 1. The arrows indicate the refrigerant flows. The thick lines indicate piping sections through which refrigerant flows. Valves and similar devices through which refrigerant does not flow are represented by dotted hatching. An indoor unit 83 labeled "Cool" operates in a cooling mode, and an indoor unit 83 labeled "Heat" operates in a heating mode. These designations also apply to the operating modes described below.

[0080] In cooling-only mode, the controller 50 switches the flow switching device 2 to a first state. The controller 51 closes the first flow control device 19 and the second opening and closing unit 31. The controller 51 opens the second flow control device 20, the first shut-off device 21, and the first opening and closing units 30. The controllers 52 control the opening degrees of the pressure reducing devices 40. The actuating valve 4 on the high-pressure side and the actuating valve 5 on the low-pressure side are opened.

[0081] Compressor 1 compresses the drawn-in refrigerant and releases it in a high-temperature / high-pressure gaseous state. The refrigerant, now in a gaseous state, flows from compressor 1 into the outdoor heat exchanger 3 via the flow diverter 2. The refrigerant flowing into the outdoor heat exchanger 3 exchanges heat with a heat transfer medium at a lower temperature than the refrigerant and consequently condenses into a liquid. The heat transfer medium is either outdoor air or water. The condensed refrigerant, now in liquid form, passes through the check valve 6d, the high-pressure side actuating valve 4, the high-pressure line 7, and the inlet branch unit 22.

[0082] The refrigerant, in a liquid state, passes through the inlet branch unit 22, the second flow control device 20, the first shut-off device 21, and the fourth opening and closing units 33, and flows into the pressure reducing devices 40 of the indoor units 83 via the liquid branch lines 42. The refrigerant flowing into the pressure reducing devices 40 is decompressed, enters a two-phase low-temperature state, and flows into the indoor heat exchangers 41. The refrigerant, having entered the indoor heat exchangers 41, exchanges heat with a non-heat exchange medium that has a higher temperature than the refrigerant, thus absorbing heat and consequently evaporating into a gas. The target heat exchange medium is, for example, indoor air or water.At this time, a cooling effect can be achieved by cooling the non-heat exchange medium.

[0083] The refrigerant that has flowed out of the interior heat exchangers 41 returns to the compressor 1 via the gas branch lines 43, the first opening and closing units 30, the low-pressure line 8, the actuating valve 5 on the low-pressure side, the check valve 6a and the flow switching device 2. Cooling main operating mode

[0084] Fig. Figure 3 is a schematic diagram illustrating an example of the refrigerant flows in the main cooling operating mode in the air conditioning device 100 according to embodiment 1.

[0085] The main cooling operating mode differs from the cooling-only operating mode in that some of the indoor units 83 also perform a heating operation. This section describes the case where indoor unit 83c performs a heating operation.

[0086] In the main cooling operating mode, it is necessary to supply the refrigerant, at a temperature higher than the non-heat exchange medium, to the indoor unit 83c, which performs a heating operation. Consequently, the controller 51 closes the second flow control device 20 and the first opening and closing unit 30c, and it opens the second opening and closing unit 31c.

[0087] Although the refrigerant flow from compressor 1 to inlet branch unit 22 is the same as in cooling-only operation, the state of the refrigerant exiting the outdoor unit 81 is different. In main cooling operation, the refrigerant exiting the outdoor unit 81 is in a two-phase gas-liquid state. This is because the air conditioning unit 100 does not dissipate the full amount of heat contained in the refrigerant at the outdoor heat exchanger 3, causing the refrigerant to reach the indoor heat exchanger 41 while a portion remains in the gaseous state.

[0088] The refrigerant that has flowed out of the compressor 1 and reached the inlet branch unit 22 flows into the interior heat exchanger 41c via the branch line 9d of the second line 9, the second opening and closing unit 31c and the gas branch line 43c.

[0089] The refrigerant flowing into the interior heat exchanger 41c exchanges heat with a non-heat-exchange medium that has a lower temperature than the refrigerant and consequently condenses into a liquid. At this time, a heating effect can be achieved by warming the non-heat-exchange medium.

[0090] The refrigerant flowing out of the interior heat exchanger 41c is decompressed in the pressure reducing device 40c, passes through the liquid branch line 42c and the first shut-off device 21, and is then split into two streams. The two split refrigerant streams flow into the respective pressure reducing devices 40a and 40b via the corresponding fourth opening and closing units 33a and 33b and the liquid branch line 42a and 42b.

[0091] The refrigerant flowing into the pressure reducing device 40a or 40b is decompressed and enters a two-phase, low-temperature state, flowing into the interior heat exchanger 41a or 41b. The refrigerant in the interior heat exchanger 41a or 41b exchanges heat with a non-heat-exchange medium that has a higher temperature than the refrigerant, thus absorbing heat and consequently evaporating into a gas. At this point, a cooling effect can be achieved by cooling the non-heat-exchange medium.

[0092] The refrigerant flowing out of the interior heat exchanger 41a and the refrigerant flowing out of the interior heat exchanger 41b pass through their respective gas branch lines 43a and 43b and their respective first opening and closing units 30a and 30b, and then combine. The combined refrigerant passes through the low-pressure line 8, the low-pressure operating valve 5, the check valve 6a, and the flow switching device 2, and returns to the compressor 1.

[0093] To simplify the explanation, the case is described in which the controller 51 closes the first flow control device 19 and the second flow control device 20. However, the first flow control device 19 and the second flow control device 20 can be opened, causing some of the refrigerant to flow into them.

[0094] When the first flow control device 19 is opened, the air conditioning unit 100 causes a portion of the refrigerant, in a liquid state, to pass through the third opening and closing unit 32c and be returned to the outdoor unit 81, without sending this portion of the refrigerant to the indoor unit 83a or 83b, which performs a cooling operation. In this case, the air conditioning unit 100 has the effect of adjusting the balance between cooling and heating capacities and also adjusting the refrigerant distribution within the air conditioning unit 100.

[0095] When the second flow control device 20 is opened, the air conditioning device 100 causes the refrigerant, which was split at the inlet branch unit 22, to flow towards the indoor units 83a and 83b, which perform a cooling operation, without sending the refrigerant to the indoor unit 83c, which performs a heating operation. Since the refrigerant does not condense in its liquid state, it can be said that such a refrigerant makes only a small contribution to heating.

[0096] The air conditioning device 100 reduces pressure losses in the indoor unit 83c, which operates in heating mode, by supplying the refrigerant in a liquid state, which contributes little to heating, to the indoor unit 83b, which operates in cooling mode. Furthermore, the air conditioning device 100 improves the uneven distribution of the refrigerant in a two-phase gas-liquid state in a manifold (not shown) contained in the indoor heat exchanger 41c by reducing the amount of refrigerant in liquid form supplied to the indoor unit 83c, which operates in heating mode.

[0097] Since the refrigerant, which has been reduced in the pressure reducing device 40c, transitions into a two-phase state, disturbances occur when the refrigerant in this two-phase state flows into the pressure reducing devices 40a and 40b. To reduce such disturbances, the air conditioning device 100 can be equipped with a refrigerant-to-refrigerant heat exchanger configured to exchange heat between refrigerant in a high-pressure state flowing from the transfer unit 82 towards the pressure reducing device 40 and refrigerant obtained by diverting a portion of the refrigerant in a high-pressure state to the first line 10, thus reducing its pressure. Heating - Main operating mode

[0098] Fig. Figure 4 is a schematic diagram illustrating an example of the refrigerant flows in the heating main operating mode in the air conditioning device 100 according to embodiment 1.

[0099] The heating main operating mode differs from the cooling main operating mode in that the number of indoor units 83 performing a heating operation is increased. Here, the case is described in which indoor units 83b and 83c are performing a heating operation.

[0100] If the number of indoor units 83 operating in heating mode is increased, an operating condition may arise in the air conditioning unit 100 in which the amount of heat required for heating cannot be guaranteed because heat is dissipated in the outdoor heat exchanger 3. Therefore, the controller 50 ensures heating capacity by switching the flow diverter 2 to a second state, causing the outdoor heat exchanger 3 to act as an evaporator. The controller 51 then closes the first opening and closing units 30b and 30c and opens the second opening and closing units 31b and 31c.

[0101] Compressor 1 compresses the drawn-in refrigerant and releases it in a high-temperature / high-pressure gaseous state. The refrigerant, in a gaseous state, released from compressor 1 passes through the flow switching device 2, the check valve 6b, the actuating valve 4 on the high-pressure side, the high-pressure line 7, and the inlet branching unit 22.

[0102] The refrigerant, having passed through the inlet branch unit 22, flows into the interior heat exchanger 41b or 41c via the corresponding second opening and closing unit 31b or 31c and the corresponding gas branch line 43b or 43c. The refrigerant flowing into the interior heat exchanger 41b or 41c exchanges heat with a non-heat exchange medium that has a lower temperature than the refrigerant, thus dissipating heat, and consequently condenses into a liquid or two-phase refrigerant. At this time, a heating effect can be achieved by warming the non-heat exchange medium.

[0103] One refrigerant stream, exiting the interior heat exchanger 41b, is decompressed by the pressure reducing device 40b and enters a two-phase state. The other refrigerant stream, exiting the interior heat exchanger 41c, is decompressed by the pressure reducing device 40c and also enters a two-phase state. One refrigerant stream, in a two-phase state, passes through the liquid branch line 42b and the third opening and closing unit 32b. The other refrigerant stream, also in a two-phase state, passes through the liquid branch line 42c and the third opening and closing unit 32c. The refrigerant streams are then combined. The combined refrigerant passes through the first shut-off device 21 and flows into the pressure reducing device 40a via the fourth opening and closing unit 33a and the liquid branch line 42a.

[0104] The refrigerant flowing into the pressure reducing device 40a is decompressed and enters a two-phase, low-temperature state before flowing into the interior heat exchanger 41a. The refrigerant in the interior heat exchanger 41a exchanges heat with a non-heat exchange medium that has a higher temperature than the refrigerant, thus absorbing heat and consequently evaporating and entering a two-phase state. At this point, a cooling effect can be achieved by cooling the non-heat exchange medium.

[0105] The refrigerant flowing out of the indoor heat exchanger 41a passes through the gas branch line 43a, the first opening and closing unit 30a, the low-pressure line 8, the actuating valve 5 on the low-pressure side, and the check valve 6c, and flows into the outdoor heat exchanger 3. The refrigerant flowing into the outdoor heat exchanger 3 exchanges heat with a heat transfer medium at a higher temperature than the refrigerant, thus absorbing heat and consequently evaporating and entering a gaseous or two-phase state. The refrigerant in a gaseous or two-phase state passes through the flow changeover device 2 and returns to the compressor 1.

[0106] To simplify the explanation, the case is described in which the controller 51 closes the first flow control device 19 and the second flow control device 20. However, the first flow control device 19 and the second flow control device 20 can be opened, causing some of the refrigerant to flow into them.

[0107] When the first flow control device 19 is opened, the air conditioning unit 100 causes a portion of the refrigerant, in a liquid state, to pass through the third opening and closing unit 32b or 32c and be returned to the outdoor unit 81, without sending this portion of the refrigerant to the indoor unit 83a, which performs a cooling operation. In this case, the air conditioning unit 100 has the effect of adjusting the balance between cooling and heating capacities and also adjusting the refrigerant distribution within the air conditioning unit 100.

[0108] When the second flow control device 20 is opened, the air conditioning device 100 directs the refrigerant, which was split at the inlet branch unit 22, towards the indoor unit 83a, which operates in a cooling mode, without sending the refrigerant to the indoor units 83b and 83c, which operate in a heating mode. Since the refrigerant does not condense in its liquid state, it can be said that such a refrigerant contributes only a small amount to heating. The air conditioning device 100 reduces the pressure losses in the indoor units 83b and 83c, which operate in a heating mode, by sending the refrigerant in a liquid state, which contributes little to heating, to the indoor unit 83a, which operates in a cooling mode.

[0109] Furthermore, since the refrigerant, whose pressure is reduced in the pressure reducing device 40b or 40c, transitions into a two-phase state, disturbances occur when the refrigerant in this two-phase state flows into the pressure reducing device 40a or 40b. To reduce such disturbances, the air conditioning device 100 can be equipped with a refrigerant-to-refrigerant heat exchanger configured to exchange heat between refrigerant in a high-pressure state flowing from the distribution unit 82 towards the pressure reducing device 40 and refrigerant obtained by diverting a portion of the refrigerant in a high-pressure state to the first line 10, thus reducing its pressure.

[0110] Furthermore, if the heat source temperature, which is the temperature of the heat transfer medium, is lower than the temperature of the non-heat exchange medium in an indoor unit 83, the refrigerant may not evaporate in the outdoor heat exchanger 3 in some cases. In such cases, the air conditioning device 100 can be configured to lower the temperature of the refrigerant flowing into the outdoor heat exchanger 3 compared to the heat source temperature by using the following configuration.

[0111] In the air conditioning device 100, a valve capable of adjusting the degree of opening is arranged in a path from the indoor heat exchanger 41 to the outdoor heat exchanger 3, thus reducing the pressure of the refrigerant flowing from the indoor heat exchanger 41 towards the outdoor heat exchanger 3. As a result, the temperature of the refrigerant flowing into the outdoor heat exchanger 3 is lower than the temperature of the heat source. For example, the air conditioning device 100 can be configured with a solenoid valve between the check valve 6c and the outdoor heat exchanger 3, with the check valve 6c being replaced by a solenoid valve, or with a solenoid valve between the indoor heat exchanger 41 and the gas branch line 43. Heat-only operating mode

[0112] Fig. Figure 5 is a schematic diagram illustrating an example of the refrigerant flows in the heating-only operating mode in the air conditioning device 100 according to embodiment 1.

[0113] In heating-only mode, the controller 50 switches the flow switching device 2 to the second state. The controller 51 closes the second flow control device 20 and the first opening and closing units 30. The controller 51 opens the first flow control device 19, the first shut-off device 21, and the second opening and closing units 31. The controllers 52 control the opening degrees of the pressure reducing devices 40. The actuating valve 4 on the high-pressure side and the actuating valve 5 on the low-pressure side are opened.

[0114] Compressor 1 compresses the drawn-in refrigerant and releases it in a high-temperature / high-pressure gaseous state. The refrigerant, in a gaseous state, released from compressor 1 passes through the flow switching device 2, the check valve 6b, the actuating valve 4 on the high-pressure side, the high-pressure line 7, and the inlet branching unit 22.

[0115] The refrigerant, which has flowed through the inlet branch unit 22, flows into the interior heat exchangers 41 via the second opening and closing units 31 and the gas branch lines 43. The refrigerant flowing into the interior heat exchangers 41 exchanges heat with a non-heat-exchange medium that has a lower temperature than the refrigerant and consequently condenses into a liquid. At this time, a heating effect can be achieved by warming the non-heat-exchange medium.

[0116] The refrigerant in a liquid state, which has flowed out of the interior heat exchangers 41, is decompressed by the pressure reducing devices 40 and passes through the liquid branch lines 42 and the third opening and closing units 32. The refrigerant that has passed through the third opening and closing units 32 passes through the first flow control device 19, the actuating valve 5 on the low-pressure side and the check valve block 6c and flows into the exterior heat exchanger 3.

[0117] The refrigerant flowing into the outdoor heat exchanger 3 exchanges heat with a non-heat exchange medium that has a higher temperature than the refrigerant, thus absorbing heat and consequently evaporating and assuming a gaseous or two-phase state. The refrigerant in a gaseous or two-phase state passes through the flow changeover device 2 and returns to the compressor 1.

[0118] To simplify the explanation, the case in which the first shut-off device 21 is opened is described. However, even if the first shut-off device 21 is closed, this does not affect operation. In any case, the flow of refrigerant is blocked by the fourth opening and closing units 33. Blockage due to refrigerant leakage

[0119] Fig. Figure 6 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in the air conditioning device 100 according to embodiment 1. The arrows indicate the refrigerant flows. The thick lines indicate pipe sections where refrigerant can escape or leak.

[0120] Refrigerant leakage can occur as a result of pipe damage caused by pitting corrosion or other reasons, poor brazing, or pipe breaks resulting from disasters.

[0121] If a refrigerant leak occurs, the air conditioning device 100 detects an increase in the refrigerant concentration by means of a refrigerant detector (not shown) located in the indoor units 83 and activates a fan located in the indoor space.

[0122] If a refrigerant leak occurs in a single indoor unit 83, the air conditioning device 100 interrupts the operation of the compressor 1 and closes all of the first opening and closing devices 300, the second opening and closing devices 310, and the first shut-off device 21. As a result, the air conditioning device 100 can block a refrigerant flow towards the indoor units 83 from the outdoor unit 81 via the distribution unit 82.

[0123] The multiple indoor units 83 communicate with each other in the relay unit 82. If an indoor unit (hereinafter referred to as the leaking indoor unit) in which refrigerant is leaking is kept in communication with another indoor unit (hereinafter referred to as the non-leaking indoor unit), the refrigerant from the non-leaking indoor unit can leak out of a refrigerant leakage area 24 via the relay unit 82. Here, the refrigerant of a non-leaking indoor unit contains not only the refrigerant present in the non-leaking indoor unit, but also the refrigerant present in the liquid branch line 42 and the gas branch line 43, which are directly connected to the non-leaking indoor unit.

[0124] Consequently, if a refrigerant leak occurs, the air conditioning device 100 interrupts the operation of the compressor 1 as described above and closes all opening and closing devices, including the first opening and closing device 300 (which also serves as an opening and closing device S for evacuation), the second opening and closing devices 310, and the first shut-off device 21. This allows the air conditioning device 100 to functionally separate the indoor unit 83 with refrigerant leakage from the indoor units 83 without refrigerant leakage, thus preventing the refrigerant from the indoor unit 83 without refrigerant leakage from leaking out of a refrigerant leakage area 24 via the transfer unit 82, as described below.

[0125] A refrigerant flow in a leakage scenario is now described. Here, the case is described in which the refrigerant leakage area 24 is present in the liquid branch line 42a within the indoor unit 83a. The refrigerant flow in a leakage scenario, as described below, is also applied to a case in which the refrigerant leakage area 24 is present in any of the liquid branch line 42a outside the indoor unit 83a, the liquid branch lines 42b and 42c, the indoor heat exchangers 41a, 41b and 41c, and the gas branch lines 43a, 43b and 43c.

[0126] As a result of the fact that the indoor unit 83a has the refrigerant leakage area 24, the refrigerant can leak out in an area from the first opening and closing unit 30a and the second opening and closing unit 31a to the refrigerant leakage area 24 via the gas branch line 43a, the indoor heat exchanger 41a and the pressure reducing device 40a.

[0127] As described above, when refrigerant leakage occurs, the air conditioning unit 100 closes the first opening and closing device 300 and the second opening and closing device 310. That is, the first opening and closing units 30a, 30b, and 30c and the second opening and closing units 31a, 31b, and 31c are closed, thus blocking the first path 13 and the second path 14. Consequently, the remaining refrigerant in the distribution unit 82 is prevented from flowing into the gas branch line 43a, and therefore the remaining refrigerant in the distribution unit 82 does not flow from the refrigerant leakage area 24 to the outside via the gas branch line 43a, the interior heat exchanger 41a, and the pressure reducing device 40a.

[0128] Furthermore, the refrigerant leaks from the refrigerant leakage area 24 within the liquid branch line 42a to the outside. When the refrigerant leaks from within the liquid branch line 42a, the internal pressure of the liquid branch line 42a decreases over time. If the pressure in the liquid branch line 42a becomes lower than that in the fourth line 11 while the first shut-off device 21 is closed, a refrigerant flow is generated towards the liquid branch line 42a from the downstream side of the first shut-off device 21 via the fourth opening and closing unit 33a in the fourth line 11. The refrigerant flowing towards the liquid branch line 42a will leak from the refrigerant leakage area 24 to the outside.

[0129] As a result of the refrigerant flow towards the liquid branch line 42a from the downstream side of the first shut-off device 21 via the fourth opening and closing unit 33a, the pressure in the fourth line 11 is reduced to a pressure lower than the pressures in the other lines in the distribution unit 82. Therefore, when the first shut-off device 21 is open, the refrigerant in the other lines in the distribution unit 82 can flow into the liquid branch line 42a via the first shut-off device 21, and consequently leaks from the refrigerant leakage area 24 to the outside. However, if the first shut-off device 21 is kept closed, the refrigerant leakage via the first shut-off device 21 can be prevented, thus preventing the refrigerant from leaking out of the other lines in the distribution unit 82.

[0130] Furthermore, the pressure in the fourth line 11 is lower than the pressures of the liquid branch lines 42b and 42c. However, the fourth opening and closing units 33b and 33c block the refrigerant flowing from the liquid branch lines 42b and 42c towards the main line 11a of the fourth line 11. As a result, the refrigerant is prevented from flowing into the branch line 11b of the fourth line 11 in the indoor units 83b and 83c without refrigerant leakage, and consequently, leakage from the refrigerant leakage area 24 to the outside is prevented.

[0131] As described above, when a refrigerant leak occurs, the air conditioning unit 100 interrupts the operation of compressor 1 and closes all of its components: the first opening and closing device 300, the second opening and closing device 310, and the first shut-off device 21. This allows the air conditioning unit 100 to functionally isolate the leaking indoor unit 83a, the gas branch line 43, and the liquid branch line 42 connected to the leaking indoor unit 83a from the remaining part of the refrigerant circuit A. As a result, the air conditioning unit 100 can block the flow of refrigerant from the outdoor unit 81 to the indoor unit 83a via the distribution unit 82.

[0132] Furthermore, the air conditioning device 100 can prevent the refrigerant in the indoor units 83b and 83c from leaking out of the refrigerant leakage area 24 via the distribution unit 82 without a refrigerant leak. That is, if a refrigerant leak occurs in the indoor unit 83, the air conditioning device 100 can limit the area of ​​refrigerant leakage to the refrigerant in the indoor unit 83a and the refrigerant in the gas branch line 43a and the liquid branch line 42a, which are connected to the indoor unit 83a. Therefore, the air conditioning device 100 can minimize the amount of refrigerant leakage when a refrigerant leak occurs.

[0133] As a further configuration for blocking refrigerant leakage, a configuration can be considered in which, for example, the pressure reducing device 40 has a blocking function and the first shut-off device 21 is omitted. However, with such a configuration, the refrigerant leaks in the liquid branch line 42b or 42c via the third opening and closing unit 32b or 32c, the main line 12a of the third line 12, the main line 11a of the fourth line 11, and the fourth opening and closing unit 33a, which is located in the branch line 11b of the fourth line 11. Consequently, with this configuration, the area of ​​the line sections from which internal refrigerant leaks out is larger than that in the configuration according to embodiment 1.

[0134] The amount of refrigerant leakage from such liquid lines is significant and can reach unacceptable levels for a large air conditioning system with a large number of connected indoor units. Since the air conditioning unit 100 is equipped with the first shut-off device 21, such situations can be avoided. Consequently, the air conditioning unit 100 is suitable for a large air conditioning system with a large number of connected indoor units.

[0135] Here, the case is described in which the pressure reducing device 40a is open, but it is preferred that the pressure reducing device 40a be closed. The electronic expansion valve that forms the pressure reducing device 40a cannot completely close a flow passage due to its structure. Consequently, even when the pressure reducing device 40a is closed, the refrigerant leaks within the interior heat exchanger 41a and the gas branch line 43a from the refrigerant leakage area 24 via the pressure reducing device 40a. However, in the air conditioning device 100, the rate of refrigerant leakage from the refrigerant leakage area 24 can be reduced by closing the pressure reducing device 40a, and it is therefore preferred that the pressure reducing device 40a be closed.

[0136] Furthermore, the first opening and closing device 300 and the first shut-off device 21 have a function to block refrigerant leakage, as described above. Since the battery 600 is connected to the first opening and closing device 300 and the battery 61 is connected to the first shut-off device 21, the first opening and closing device 300 and the first shut-off device 21 can be operated in the event of a power failure. Consequently, the safety of the air conditioning device 100 can be further improved.

[0137] As described above, the air conditioning device 100 according to embodiment 1 is capable of simultaneous cooling and heating and has a configuration that blocks refrigerant flow in the event of a refrigerant leak. As described above, the following applies: Since the air conditioning device 100 is configured to be capable of simultaneous cooling and heating, and consequently requires a plurality of opening and closing units, it is likely that an area will be created that is difficult to evacuate. However, with the configuration described above, the entire refrigerant circuit A of the air conditioning device 100 can be safely evacuated. The following describes the case in which part of the refrigerant circuit A is evacuated.

[0138] Evacuation in the air conditioning unit 100 is performed to remove air and moisture from the ducts. Without removing the air and moisture from the ducts in the air conditioning unit 100, its performance would deteriorate, as air does not undergo phase changes. If operation is carried out while air has not been removed from a duct in the air conditioning unit 100, compressor 1 can be damaged, especially if the refrigerant is highly flammable. Furthermore, if moisture is not removed from a duct in the air conditioning unit 100, the refrigeration oil can degrade, potentially damaging compressor 1. For these reasons, evacuation in the air conditioning unit 100 is performed during the installation process.

[0139] This section describes the features necessary to perform both simultaneous cooling and heating operation and refrigerant blocking. To ensure simultaneous cooling and heating operation, the air conditioning device 100 must have the first path 13, the second path 14, the third path 15, and the fourth path 16, and it also requires the first opening and closing device 300 and the second opening and closing device 310. Furthermore, the air conditioning device 100 must have the first shut-off device 21 in the fourth path 16 to block refrigerant.

[0140] The above-mentioned air conditioning device 100 has a configuration capable of providing a path for evacuation as described below by having the first opening and closing device 300 as the opening and closing device S for evacuation.

[0141] In the air conditioning unit 100, which has the configuration mentioned above, evacuation is carried out from the first path 13. That is, evacuation is carried out by drawing air – as a fluid – into the first path 13 from within the distribution unit 82 and the indoor units 83, while the first path 13 is not blocked but open, allowing the fluid to flow, and then by drawing the air drawn into the first path 13 by a vacuum pump, so that the air is released into the atmosphere. Evacuation route

[0142] Fig. Figure 7 is a schematic diagram illustrating an example of airflows during evacuation in the air conditioning device 100 according to embodiment 1. The arrows indicate the refrigerant flows during evacuation.

[0143] Here is described the case in which a vacuum pump 25 is connected to the low-pressure line service port 72, but a vacuum pump can be connected to any location, such as the high-pressure line service port 71, as long as evacuation can be carried out for the entire air conditioning unit 100.

[0144] However, since the forwarding unit 82 and the indoor units 83 are each located in a place that is difficult to reach by hand, such as the floor slab, it is preferred that a vacuum pump be connected to the low-pressure line maintenance connection 72 or the high-pressure line maintenance connection 71, for reasons of design feasibility.

[0145] Since air is a gas, it can be removed relatively easily by vacuuming. However, to completely remove moisture, it is necessary to achieve a level of vacuum sufficient for the moisture to evaporate. For example, according to the publication "Refrigeration" by the Japan Society of Refrigerating and Air Conditioning Engineers in November 1998, evacuation requires reducing the internal pressure of a pipe to an absolute pressure of 2 mmHg (approximately 270 Pa). This pressure is one three-hundredth of atmospheric pressure.

[0146] Since the pressure inside the air conditioning unit 100 drops during evacuation, a device configured to operate by the pressure differential of a refrigerant, particularly a pilot-type solenoid valve, will not function correctly. If the air conditioning unit 100 is configured to provide an evacuation path by actuating a pilot-type solenoid valve, this evacuation path cannot be guaranteed. Therefore, to ensure an evacuation path in the air conditioning unit 100, it is necessary to pre-open expansion valves driven by a stepper motor and solenoid valves whose open state is maintained by spring force.

[0147] The first flow control device 19, the second flow control device 20, and the pressure reduction device 40 are each valves driven by a stepper motor and opened to a degree that is set by the factory at the time of delivery. Furthermore, since the first opening / closing unit 30 and the first shut-off device 21 are each on / off valves held open by a spring force or similar force when no energy is supplied, the first opening / closing unit 30 and the first shut-off device 21 are held open during evacuation, which is carried out in a non-powered state. The opening / closing state of the second opening / closing unit 31 during evacuation is not particularly restricted, but in this case, the second opening / closing unit 31 is closed.

[0148] The third opening and closing units 32 are configured to allow a refrigerant flow from the indoor units 83 to the distribution unit 82 and to block a flow in the opposite direction. Although the third opening and closing units 32 allow a refrigerant flow from the indoor units 83 to the distribution unit 82, they also block an airflow that is to be evacuated from the indoor units 83 to the distribution unit 82, because the internal pressure of the air conditioning device 100 becomes low after the vacuum pump 25 is activated.

[0149] The check valves forming the third opening and closing units 32 are each generally configured to open by lifting a valve body due to a pressure differential between the inlet and outlet sides. Therefore, when the vacuum pump 25 is operated, the following applies: As the pressure within the air conditioning device 100 decreases, each check valve cannot maintain a pressure differential between the inlet and outlet sides, and consequently, the valve body cannot be lifted. As a result, the check valve is closed and blocks the airflow that is to be evacuated. Consequently, in the third path 15, the third opening and closing units 32 block the airflow that is to be evacuated.

[0150] The fourth opening and closing units 33 are configured to allow a refrigerant flow from the distribution unit 82 to the indoor units 83 and to block a flow in the opposite direction. Although the fourth opening and closing units 33 allow a refrigerant flow from the distribution unit 82 to the indoor units 83, they also block an airflow to be evacuated from the distribution unit 82 to the indoor units 83, as the internal pressure of the air conditioning device 100 decreases after the vacuum pump 25 is activated. The check valves that form the fourth opening and closing units 33 are each generally configured to open by lifting a valve body due to a pressure differential between the inlet and outlet sides.

[0151] When the vacuum pump 25 is operated, the following applies: Since the pressure inside the air conditioning unit 100 becomes low, each check valve cannot maintain a pressure differential between the inlet and outlet sides, and consequently, the valve body cannot be raised. As a result, the check valve is closed and blocks the airflow that is to be evacuated. Consequently, in the fourth path 16, the airflow to be evacuated is blocked by the fourth opening and closing units 33.

[0152] As described above, even if a power source is not connected to the air conditioning unit 100 during installation, the first path 13 is not blocked, thus allowing fluid to pass through it. Consequently, an evacuation path within the air conditioning unit 100 is ensured. Airflow during evacuation

[0153] When the vacuum pump 25 is operated, air and moisture present in each line are drawn into the vacuum pump 25 and released into the atmosphere, as described below.

[0154] Air and moisture present in high-pressure line 7, main line 9a, second line 9, and a portion of branch lines 9b, 9c, and 9d are drawn in by the vacuum pump 25 via the inlet branch unit 22, the second flow control device 20, the first flow control device 19, the outlet junction unit 23, and low-pressure line 8, and discharged into the atmosphere. The portion of each branch line 9b, 9c, or 9d is a section on the main line 9a side, formed by splitting the respective branch line 9b, 9c, or 9d at the second opening and closing unit 31a, 31b, or 31c.At this time, air and moisture present in the inlet branching unit 22, the second flow control device 20, the first flow control device 19, the outlet merging unit 23 and the low-pressure line 8 are also drawn into the vacuum pump 25 and released into the atmosphere.

[0155] Since the first shut-off device 21 is open, air and moisture present in a portion of the main line 11a, the fourth line 11, and a portion of the branch lines 11b, 11c, and 11d are drawn into the vacuum pump 25 via the first flow control device 19, the outlet merging unit 23, and the low-pressure line 8, and discharged into the atmosphere. The portion of the main line 11a of the fourth line 11 is a section on the side of the first shut-off device 21 from a connection point P1 of the main line 11a to the line equipped with the first flow control device 19. The portion of each branch line 11b, 11c or 11d is an area on the side of the main line 11a below the two areas obtained by dividing the corresponding branch line 11b, 11c or 11d at the fourth opening and closing unit 33a, 33b, or 33c.

[0156] Air and moisture present in the main line 12a of the third line 12 and part of the branch lines 12b, 12c and 12d combine to form the air and moisture present in the main line 11a of the fourth line 11. The combined air and moisture is drawn into the vacuum pump 25 via connection point P1, the first flow control device 19, the outlet merging unit 23 and the low-pressure line 8 and discharged into the atmosphere.

[0157] Since the first opening and closing units 30a, 30b and 30c are open, the air and moisture present in the remaining part of branch lines 11b, 11c and 11d, the remaining part of branch lines 12b, 12c and 12d, the liquid branch lines 42a, 42b, 42c, the interior heat exchangers 41a, 41b and 41c, the gas branch lines 43a, 43b and 43c and the first line 10 pass through the first path 13. The air and moisture that have passed through the first path 13 are drawn into the vacuum pump 25 via the outlet merging unit 23 and the low-pressure line 8 and discharged into the atmosphere.

[0158] The air and moisture present in the remaining part of branch lines 9b, 9c and 9d are drawn into the airflow and moisture in the respective branch lines 10b, 10c and 10d, then drawn into the vacuum pump 25 via the outlet merging unit 23 and the low-pressure line 8 and released into the atmosphere.

[0159] As described above, the air conditioning device 100 can vacuum dry all lines in the forwarding unit 82, the interior units 83, the high pressure line 7 and the low pressure line 8.

[0160] Although Fig. Figure 7 illustrates the case where evacuation is carried out from one location. It is preferred that the evacuation be carried out on both the high-pressure line 7 and the low-pressure line 8. This is because the distance the air travels increases as the distance from the vacuum pump 25 increases, and it takes longer to carry out the evacuation.

[0161] The above description describes the case in which the first opening and closing device 300 also serves as the opening and closing device S for evacuation, and the evacuation is carried out from the first path 13. However, the second opening and closing device 310 can also serve as the opening and closing device S for evacuation, and the evacuation can be carried out from the second path 14. Evacuation procedure

[0162] A specific evacuation procedure is described below.

[0163] Prior to evacuation, a worker connects the outdoor unit 81, the distribution unit 82, and the indoor units 83 to form a refrigerant circuit A. The worker connects the outdoor unit 81, the distribution unit 82, and the indoor units 83 using the high-pressure line 7, the low-pressure line 8, the liquid branch lines 42, and the gas branch lines 43, after ensuring that the actuating valve 4 on the high-pressure side and the actuating valve 5 on the low-pressure side of the outdoor unit 81 are closed.

[0164] Next, the worker fills refrigerant circuit A with a gas for an airtightness test. Nitrogen gas, for example, is used as the gas for the airtightness test.

[0165] Next, the worker connects an external circuit 76, described below, to the refrigerant circuit A.

[0166] Fig. Figure 8 is a schematic diagram illustrating an example of a method for connecting the external circuit 76 involved in the evacuation in the air conditioning device 100 according to embodiment 1. The arrows indicate the airflows. With reference to Fig. Section 8 describes an example of a preferred evacuation procedure.

[0167] The evacuation is carried out by the worker by connecting the external circuit 76 to the refrigerant circuit A. The external circuit 76 includes a measuring manifold 70, the vacuum pump 25, and charging hoses 75a, 75b, and 75c. The measuring manifold 70 has three connections: a low-pressure side connection 70a, a high-pressure side connection 70b, and a supply side connection 70c. The measuring manifold 70 includes a low-pressure side gauge 70a1, which is capable of displaying the pressure applied at the low-pressure side connection 70a, and a high-pressure side gauge 70b1, which is capable of displaying the pressure applied at the high-pressure side connection 70b.

[0168] The vacuum pump 25 is connected to the supply side port 70c of the measuring manifold 70 via the charging hose 75c. The vacuum pump 25 is connected downstream of the charging hose 75c, in the direction of air flow during evacuation from an external valve 74 located in the charging hose 75c.

[0169] The external circuit 76 has a refrigerant cylinder 73 (a refrigerant bottle) that stores refrigerant. The refrigerant cylinder 73 is connected to the charging hose 75c. Refrigerant charging is carried out in the circuit where evacuation has been completed. If, after evacuation, the refrigerant cylinder 73 is connected to the charging hose 75c, there is a possibility that air may enter the circuit where evacuation was completed during the connection process. For this reason, it is preferred that the connection of the refrigerant cylinder 73 to the charging hose 75c be carried out before evacuation.

[0170] For evacuation, the external circuit 76, which has the configuration described above, is connected to the refrigerant circuit A. More precisely: The charging hose 75a, which is connected to the low-pressure side port 70a of the measuring manifold 70, is connected to the low-pressure line service port 72. Furthermore, the charging hose 75b, which is connected to the high-pressure side port 70b of the measuring manifold 70, is connected to the high-pressure line service port 71. The low-pressure line service port 72 and the high-pressure line service port 71 are, for example, of the valve insert locking type, and they are opened by connecting them to the corresponding charging hose 75a and charging hose 75b.The low-pressure line service port 72 and the high-pressure line service port 71 are each, for example, covered with a metal screw-type cap at the time of delivery from a factory, and consequently the low-pressure line service port 72 and the high-pressure line service port 71 are not accidentally opened.

[0171] The connection procedure is not limited to the procedure described above. After the measuring manifold 70 has been connected to the refrigerant circuit A via the charging hose 75a and the charging hose 75b, the charging hose 75c can be connected to the measuring manifold 70, and then the vacuum pump 25 and the refrigerant cylinder 73 are connected to the charging hose 75c.

[0172] Through the procedure described above, the circuit 76, which is involved in the evacuation, is connected to the refrigerant circuit A. The operator then manually opens an external valve 74. This procedure opens the charging hoses 75, the high-pressure line 7, the low-pressure line 8, the transfer unit 82, and the interior units 83 to the atmosphere. During evacuation, the external valve 74 remains open, and a valve 73a of the refrigerant cylinder 73 remains closed.

[0173] Next, the operator activates vacuum pump 25. The operator checks whether a vacuum is maintained by referring to a vacuum gauge attached to vacuum pump 25. Once a vacuum is maintained in refrigerant circuit A, vacuum pump 25 continues to operate, causing moisture in refrigerant circuit A to evaporate. Next, the operator closes external valve 74. After closing external valve 74, the operator shuts down vacuum pump 25 and leaves it running for a predetermined period or longer. The operator then checks the low-pressure side gauge 70a1 and the high-pressure side gauge 70b1, determines that no moisture remains if the pressure rise is less than a predetermined change value, and terminates the evacuation.

[0174] After evacuation, the operator loads the refrigerant. While loading the refrigerant, the operator opens operating valve 4 on the high-pressure side and operating valve 5 on the low-pressure side. Then, the operator opens valve 73a of refrigerant cylinder 73. This procedure fills refrigerant circuit A with the refrigerant from refrigerant cylinder 73. The refrigerant loading is carried out by checking the low-pressure side gauge 70a1 and the high-pressure side gauge 70b1. The amount of refrigerant to be filled into refrigerant circuit A is calculated based on the value specified by the manufacturer, using the lengths of the lines that make up refrigerant circuit A and the capacities of the distribution unit 82 and the indoor units 83.When refrigerant is charged, the valve 73a of the refrigerant cylinder 73 is opened, and the calculated amount of refrigerant is charged into the refrigerant circuit A.

[0175] After the refrigerant has been charged, the high pressure line service port 71 and the low pressure line service port 72 are closed, and all external circuits are removed. Effects of embodiment 1

[0176] The air conditioning device 100 according to embodiment 1, in which the refrigerant circuit A is formed by connecting the outdoor unit 81, a plurality of indoor units 83, and the distribution unit 82 by refrigerant lines, is capable of performing simultaneous cooling and heating operation. The distribution unit 82 has the first path 13, which is formed by the first line 10, and allows refrigerant to flow from the multiple indoor units 83 to the distribution unit 82, and the first opening and closing device 300, which individually blocks or allows the refrigerant to pass through as it flows from each indoor unit 83 toward the distribution unit 82.

[0177] The distribution unit 82 has a second path 14, formed by the second line 9, which allows refrigerant to flow from the distribution unit 82 to each indoor unit 83, and a second opening and closing device 310, which individually blocks or allows the refrigerant to pass from the distribution unit 82 to each indoor unit 83. The distribution unit 82 has a third path 15, formed by the third line 12, which allows refrigerant to flow from each indoor unit 83 to the distribution unit 82, and a fourth path 16, formed by the fourth line 11, which allows refrigerant to flow from the distribution unit 82 to each indoor unit 83.

[0178] The transfer unit 82 has the first shut-off device 21, which is configured to open in a non-powered state, allowing the refrigerant to flow in the fourth path 16, and to close in a powered state, blocking the refrigerant flow in the fourth path 16. In the transfer unit 82, the second branching unit 18 has the opening and closing device S for evacuation, which is configured to open in a non-powered state, allowing fluid to flow in at least one of the first path 13, the second path 14, the third path 15, and the fourth path 16, and to close in a powered state, blocking the refrigerant flow in at least one of the paths.

[0179] With the configuration described above, the air conditioning device 100 blocks a refrigerant flow from the outdoor unit 81 towards the indoor units 83 by closing the second opening and closing device 310, the first shut-off device 21, and the evacuation opening and closing device S when a refrigerant leak occurs. Furthermore, the air conditioning device 100 allows fluid flow in at least one of the first path 13, the second path 14, the third path 15, and the fourth path 16 by opening the evacuation opening and closing device S in a de-energized state, thus ensuring an evacuation path. As a result, the air conditioning device 100 improves design flexibility while being capable of simultaneous cooling and heating operation and is equipped with a refrigerant leakage blocking function.This means that the air conditioning device 100 can both ensure safety in the event of a leak and improve constructability.

[0180] The air conditioning device 100 is equipped with a battery 61 which is configured to operate the first shutdown device 21 in the event of a power malfunction.

[0181] With the configuration described above, the air conditioning unit 100 can prevent refrigerant leakage in the event of an energy malfunction and consequently improve safety.

[0182] The fourth line 11 comprises the main line 11a and several branch lines 11b, 11c, and 11d, which branch off from the main line 11a towards the several indoor units 83. The first shut-off device 21 is formed by a solenoid valve located in the main line 11a of the fourth line 11.

[0183] With the configuration described above, the cost of the air conditioning device 100 can be reduced by using the first shut-off device 21, compared to the configuration in which each of the branch lines 11b, 11c and 11d is equipped with a solenoid valve.

[0184] The fourth line 11 comprises the main line 11a and several branch lines 11b, 11c, and 11d, which branch off from the main line 11a towards the several indoor units 83. The first shut-off device 21 is formed by a plurality of solenoid valves arranged in the several branch lines 11b, 11c, and 11d of the fourth line 11.

[0185] With the configuration described above, the air conditioning unit 100 can only block indoor units 83 with refrigerant leakage, and an indoor unit 83 without refrigerant leakage can continue cooling / heating operation.

[0186] The air conditioning unit 100 is equipped with a battery 60, which is configured to operate the opening and closing device S for evacuation in the event of a power malfunction.

[0187] With the configuration described above, the air conditioning unit 100 can prevent refrigerant leakage in the event of an energy malfunction and consequently improve safety.

[0188] In the air conditioning device 100, one or both of the first opening and closing device 300 and the second opening and closing device 310 also serve as the opening and closing device S for evacuation, and they open in a state not supplied with energy and close in a state supplied with energy.

[0189] With the configuration described above, the air conditioning unit 100 can perform an evacuation from one or both of the first path 13 and the second path 14. Design 2

[0190] Fig. Figure 9 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device 101 according to embodiment 2. The arrows indicate the refrigerant flows. The thick lines indicate piping sections where refrigerant can escape or leak. The air conditioning device 101 according to embodiment 2 differs from the air conditioning device 100 according to embodiment 1 in that the configuration of one or both of the first opening and closing units 30 and the second opening and closing units 31, which also serve as the opening and closing device S for evacuation, is different. In embodiment 2, mainly one configuration is described that differs from that of embodiment 1, and configurations not described in embodiment 2 are the same as those of embodiment 1.

[0191] Each first opening and closing unit 30 according to embodiment 1 is a pilot-type solenoid valve configured to induce refrigerant pressure by driving a pilot valve with an electromagnetic force, so that the main valve operates with a refrigerant pressure differential. Meanwhile, each opening and closing unit 30 according to embodiment 2 is an electronic expansion valve configured to be driven by a stepper motor or similar device, and whose opening degree can be adjusted.

[0192] During normal operation of the air conditioning unit 101, the following applies: Since the pressure in the first line 10 is always lower than that in each gas branch line 43, a pressure differential of the refrigerant can be ensured. However, in the event of a leak, the pressure in the gas branch line 43 can become lower than that in the first line 10. Consequently, if each first opening and closing unit 30 is a pilot-type solenoid valve, the main valve can be lifted by the pressure, thereby opening the flow passage. Therefore, there is a possibility that the first opening and closing unit 30 will not fully perform its blocking function.

[0193] Since each first opening and closing unit 30 of the air conditioning device 101 is an electronic expansion valve, the first opening and closing unit 30 can safely block the refrigerant flow in the first path 13, regardless of whether the pressure in the first line 10 is lower than that in the gas branch lines 43, in the event of a leak.

[0194] The air conditioning device 101 performs a cooling and heating operation similar to that according to embodiment 1. In the air conditioning device 101, the processes in the heating main operating mode can be improved by adjusting the opening degree of each first opening and closing unit 30.

[0195] As described above, the following applies to the air conditioning system: If the heat source temperature is lower than that of a heat exchanger medium in an indoor unit, it is necessary to reduce the temperature of the refrigerant flowing into the outdoor heat exchanger to a lower temperature than the heat source temperature. To reduce the refrigerant temperature to a lower temperature than the heat source temperature, it is preferred that a valve with an adjustable opening degree be provided in the path from the indoor heat exchanger to the outdoor heat exchanger.

[0196] In the air conditioning device 101 according to embodiment 2, the first opening and closing unit 30 is an electronic expansion valve, and by reducing the pressure of the refrigerant by means of the first opening and closing unit 30, the temperature of the refrigerant flowing into the outdoor heat exchanger 3 can be reduced. Consequently, in the air conditioning device 101, the first opening and closing unit 30 can reduce the temperature of the refrigerant flowing into the outdoor heat exchanger 3 to a temperature lower than the heat source temperature.

[0197] Although Fig. Figure 9 illustrates a case in which only the first opening and closing unit 30 is formed by an electronic expansion valve configured to be driven by a stepper motor or similar device. However, the air conditioning device 101 is not limited to this configuration. In the air conditioning device 101, the second opening and closing unit 31 can be formed by an electronic expansion valve configured to be driven by a stepper motor or similar device. Furthermore, both the first opening and closing unit 30 and the second opening and closing unit 31 of the air conditioning device 101 can be formed by electronic expansion valves.

[0198] In short: The air conditioning device 101 has a configuration in which one or both of the first opening and closing units 30 and the second opening and closing units 31 are electronic expansion valves. If the second opening and closing unit 31 is formed by an electronic expansion valve in the air conditioning device 101, no effect on pressure adjustment in the heating main operating mode can be achieved, but other effects can be achieved. Blockage due to refrigerant leakage

[0199] As in Fig. As shown in Figure 9, in the event of a refrigerant leak, the air conditioning device 101 closes the first opening and closing device 300, the second opening and closing device 310, and the first shut-off device 21. Compared to the air conditioning device 100, the air conditioning device 101 has a configuration in which the first opening and closing units 30, which form the first opening and closing device 300, and / or the second opening and closing units 31, which form the second opening and closing device 310, are formed by expansion valves. Compared to the air conditioning device 100, the air conditioning device 101 can reliably block a refrigerant flow in the first path 13 and / or second path 14 when a refrigerant leak occurs. As a result, the air conditioning device 101 can further reduce the amount of refrigerant leakage compared to the air conditioning device 100. evacuation

[0200] The electronic expansion valves forming the first opening and closing units 30, and / or those forming the second opening and closing units 31, are set to open at a predetermined degree at the time of delivery from the factory. That is, the electronic expansion valves forming the first opening and closing units 30, and / or those forming the second opening and closing units 31, are open in a de-energized state. Consequently, the air conditioning device 101 can provide a path for evacuation. Effects of the air conditioning device 101 according to embodiment 2

[0201] Since the first opening and closing units 30 and / or the second opening and closing units 31 are formed by expansion valves, the air conditioning device 101 can achieve not only an effect similar to that of embodiment 1, but also an effect described below, compared to a case in which the first opening and closing units 30 and / or the second opening and closing units 31 are formed by solenoid valves. The air conditioning device 101 can further reduce the amount of refrigerant leakage compared to the air conditioning device 100. embodiment 3

[0202] Fig. Figure 10 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device 102 according to embodiment 3. The arrows indicate the refrigerant flows. The thick lines indicate piping sections where refrigerant can escape or leak. Compared to the air conditioning device 100 according to embodiment 1, the air conditioning device 102 according to embodiment 3 also functions as the opening and closing device S for evacuation. The configuration of one or both of the first opening and closing units 30 and the second opening and closing units 31 is different. In embodiment 3, mainly one configuration is described that differs from that of embodiment 1, and configurations not described in embodiment 3 are the same as those of embodiment 1.

[0203] Each first opening and closing unit 30 in embodiment 3 has a configuration in which two solenoid valves, configured to remain open in an unpowered state by a spring force or similar force, are arranged in series. More precisely, the solenoid valves are pilot-type solenoid valves. The solenoid valve on the gas branch line 43 side is configured to provide a blocking function in the event of a refrigerant leak. The solenoid valve on the gas branch line 43 side is configured to provide a blocking function when the pressure in the gas branch line 43 becomes lower than that in the first line 10. The solenoid valve on the first line 10 side is configured to provide a blocking function during normal operation.The solenoid valve on the side of the first line 10 is configured to provide a blocking function when the pressure in the first line 10 becomes lower than that in the gas branch line 43.

[0204] Similar to embodiment 2, the air conditioning device 102 can therefore safely block a refrigerant flow in the first path 13, regardless of whether the pressure in the first line 10 is lower than that in the gas branch lines 43, in the event of a refrigerant leak.

[0205] Although Fig. Figure 10 illustrates a case in which only each of the first opening and closing units 30 has a configuration in which two pilot-type solenoid valves are connected in series. However, the air conditioning device 102 is not limited to this configuration. In the air conditioning device 102, each of the second opening and closing units 31 can have a configuration in which two pilot-type solenoid valves are connected in series. Furthermore, the air conditioning device 102 can have a configuration in which each of the first opening and closing units 30 and each of the second opening and closing units 31 has a configuration in which two pilot-type solenoid valves are connected in series. In short, the air conditioning device 102 has a configuration in which each first opening and closing unit 30 and / or each second opening and closing unit 31 is configured as two pilot-type solenoid valves connected in series. Blockage due to refrigerant leakage

[0206] As in Fig. As shown in Figure 10, in the event of a refrigerant leak, the air conditioning device 102 closes the first opening and closing device 300, the second opening and closing device 310, and the first shut-off device 21. Compared with the air conditioning device 100, the air conditioning device 102 has a configuration in which the first opening and closing units 30, which form the first opening and closing device 300, and / or the second opening and closing units 31, which form the second opening and closing device 310, are each formed by two pilot-type solenoid valves connected in series.

[0207] Compared to the air conditioning device 100, the air conditioning device 102 can reliably block a refrigerant flow in the first path 13 and / or second path 14 if a refrigerant leak occurs. As a result, the air conditioning device 102 can further reduce the amount of refrigerant leakage compared to the air conditioning device 100. evacuation

[0208] During evacuation, i.e., when the air conditioning device 102 is in a de-energized state, the following applies: Since both of the two solenoid valves of each third opening and closing unit 32 are open, the air conditioning device 102 can provide an evacuation path from the third path 15. Because the air conditioning device 102 can provide an evacuation path from the third path 15, the battery 600, which is used to perform the evacuation from the first path 13, is not required in this case.

[0209] If every fourth opening and closing unit 33 has a configuration in which two pilot-type solenoid valves are connected in series, an evacuation path from the fourth path 16 can be ensured. Since the air conditioning device 102 can ensure an evacuation path from the fourth path 16, the battery 600, which is used to perform the evacuation from the first path 13, is not required in this case.

[0210] If every third opening and closing unit 32 and every fourth opening and closing unit 33 have a configuration in which two pilot-type solenoid valves are connected in series, evacuation paths can be ensured from the third path 15 and fourth path 16. Consequently, the battery 600, which is required to perform evacuation from the first path 13, is not necessary. Effects of the air conditioning device 102 according to embodiment 3

[0211] The air conditioning device 102 can achieve not only a similar effect to that of embodiment 1, but also the effect described below. In the air conditioning device 102, each first opening and closing unit 30 and / or each second opening and closing unit 31 has a configuration in which two pilot-type solenoid valves are connected in series. Consequently, the air conditioning device 102 can further reduce the amount of refrigerant leakage compared to a case in which each first opening and closing unit 30 and / or each second opening and closing unit 31, which also serves as the opening and closing device S for evacuation, is formed as a single pilot-type solenoid valve.

[0212] Here, the operation of a solenoid valve is faster than that of an electronic expansion valve, whose opening degree can be adjusted using a stepper motor. Compared to the air conditioning device 101, in which each first opening and closing unit 30 and / or each second opening and closing unit 31 is formed by an electronic expansion valve, the air conditioning device 102 can close a flow passage faster and further reduce the amount of refrigerant leakage. The air conditioning device 102 has advantages over the air conditioning device 101, namely by reducing the amount of refrigerant leakage when the refrigerant leakage rate is high. Design 4

[0213] Fig. Figure 11 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device 103 according to embodiment 4. The arrows indicate the refrigerant flows. The thick lines indicate piping sections where refrigerant can escape or leak. The air conditioning device 103 according to embodiment 4 differs from the air conditioning device 100 according to embodiment 1 in that the configuration of every third opening and closing unit 32 and / or every fourth opening and closing unit 33 is different. In embodiment 4, mainly one configuration is described that differs from that of embodiment 1, and configurations not described in embodiment 4 are the same as those of embodiment 1.

[0214] Each of the third opening and closing units 32 according to embodiment 1 is formed by a check valve. The operation of the check valves is unstable in some cases due to the direction of the pressure to be applied, as described above. However, each of the third opening and closing units 32 according to embodiment 4 is formed by a solenoid valve that opens in a non-energized state, allowing refrigerant to pass, and closes in an energized state, blocking a refrigerant flow. The solenoid valve can open and close a flow passage regardless of the direction of the pressure to be applied. Since the third opening and closing units 32 are solenoid valves, the air conditioning device 103 can reliably block a refrigerant flow in the third path 15 in the event of a refrigerant leak.The third opening and closing units 32 can be electronic expansion valves.

[0215] The air conditioning device 103 is equipped with a battery 620, which is connected to the third opening and closing device 320. The battery 600, which is connected to the first opening and closing device 300, is omitted in the air conditioning device 103.

[0216] Battery 620 is a power source for operating the third opening and closing device 320 in the event of a power failure. Battery 620 is designed to prevent refrigerant leakage by operating the third opening and closing device 320, even when no power is supplied to the air conditioning unit 103. With battery 620 connected to the third opening and closing device 320, the air conditioning unit 103 can prevent refrigerant leakage in the event of a power failure, thus improving safety. Battery 620 includes batteries 62a, 62b, and 62c for the respective third opening and closing units 32a, 32b, and 32c.

[0217] Furthermore, in the air conditioning device 100 according to embodiment 1, one or both of the first opening and closing device 300 and the second opening and closing device 310 also serve as an opening and closing device S for evacuation. In the air conditioning device 103 according to embodiment 4, one or both of the third opening and closing device 320 and the fourth opening and closing device 330 also serve as an opening and closing device S for evacuation.

[0218] The air conditioning device 103 according to embodiment 4 differs from the air conditioning device 100 according to embodiment 1 by the above configuration. Blockage due to refrigerant leakage

[0219] As in Fig. As shown in Figure 11, in the event of a refrigerant leak, the air conditioning device 103 closes the first opening and closing device 300, the second opening and closing device 310, the third opening and closing device 320, and the first shut-off device 21. Compared to the air conditioning device 100, the air conditioning device 103 has a configuration in which each third opening and closing unit 32, forming the third opening and closing device 320, is formed by a solenoid valve. With this configuration, the air conditioning device 103 can reliably block a refrigerant flow in the third path 15, compared to the air conditioning device 100. As a result, the air conditioning device 103 can further reduce the amount of refrigerant leakage compared to the air conditioning device 100.

[0220] Although Fig. Figure 11 illustrates a case in which only the third opening and closing units 32 are solenoid valves; the air conditioning device 103 is not limited to this configuration. Since the pressure in the third line 12, in which the third opening and closing units 32 are arranged, and the pressure in the fourth line 11, in which the fourth opening and closing units 33 are arranged, fluctuates depending on the operating condition, the pressure relations between the third line 12 and the liquid branch lines 42 and those between the fourth line 11 and the liquid branch lines 42 are not constant.

[0221] Consequently, in the air conditioning device 103, the fourth opening and closing units 33 can be formed by solenoid valves. Furthermore, the air conditioning device 103 can have a configuration in which both the third opening and closing units 32 and the fourth opening and closing units 33 are solenoid valves. In short, the air conditioning device 103 has a configuration in which every third opening and closing unit 32 and / or every fourth opening and closing unit 33 is a solenoid valve or an electronic expansion valve. evacuation

[0222] Since a solenoid valve or an electronic expansion valve, which are contained in every third opening and closing unit 32, is open in a non-energized state, the air conditioning device 103 can provide an evacuation path from the third path 15 during evacuation. Because the air conditioning device 103 can provide an evacuation path from the third path 15, the battery 600, which is used to perform the evacuation from the first path 13, is not required in this case.

[0223] If every fourth opening and closing unit 33 is a solenoid valve or an expansion valve configured to be open in a non-powered state, an evacuation path from the fourth path 16 can be ensured. Since the air conditioning device 103 can ensure an evacuation path from the fourth path 16, the battery 600, which is used to perform the evacuation from the first path 13, is not required in this case.

[0224] If every third opening and closing unit 32 and every fourth opening and closing unit 33 are solenoid valves or expansion valves configured to be open in a non-powered state, evacuation paths can be ensured from the third path 15 and the fourth path 16.

[0225] Consequently, battery 600, which is needed to carry out the evacuation from the first path 13, is not necessary. Effects of the air conditioning device 103 according to embodiment 4

[0226] Since every third opening and closing unit 32 and / or every fourth opening and closing unit 33 is formed by a solenoid valve or an electronic expansion valve, the air conditioning device 103 can achieve not only a similar effect to that of embodiment 1, but also an effect described below, compared to a case in which every third opening and closing unit 32 and / or every fourth opening and closing unit 33 is formed by a check valve. The air conditioning device 103 can further reduce the amount of refrigerant leakage compared to the air conditioning device 100. Design 5

[0227] Fig. Figure 12 is a schematic diagram illustrating an example of the refrigerant flows in a case of refrigerant leakage in an air conditioning device 104 according to embodiment 5. The arrows indicate the refrigerant flows. The thick lines indicate piping sections where refrigerant can escape or leak. The air conditioning device 104 according to embodiment 5 differs from the air conditioning device 100 according to embodiment 1 in that the configuration of the first branching unit 17 is different. In embodiment 5, a configuration is mainly described that differs from that of embodiment 1, and configurations not described in embodiment 5 are the same as those of embodiment 1.

[0228] The first branching unit 17 has a second switching device 340 configured to open in a de-energized state and to close in a energized state, and the first opening and closing units 30 of the first opening and closing device 300 are designed as solenoid valves 35 with orifices. The battery 600 connected to the first opening and closing device 300 in embodiment 1 is omitted, but the battery 600 is connected to the second switching device 340.

[0229] In the air conditioning device 100 according to embodiment 1, one or both of the first opening and closing device 300 and the second opening and closing device 310 are configured to also serve as the opening and closing device S for evacuation. In the air conditioning device 104 according to embodiment 5, the opening and closing device S for evacuation comprises the third opening and closing device 320 and the second shut-off device 340.

[0230] In the opening and closing device S for evacuation according to embodiment 5, the first opening and closing device 300 functions in such a way that it allows air - as a fluid - to flow in the first path 13 in a state not subjected to energy, and the second shut-off device 340 functions in such a way that it blocks a refrigerant flow in a state subjected to energy.

[0231] The second shut-off device 340 has second shut-off valves 34a, 34b, and 34c. The second shut-off valves 34a, 34b, and 34c are designed as solenoid valves configured to close when energized and open when de-energized. The second shut-off valves 34a, 34b, and 34c are each located on the side of the corresponding indoor unit 83a, 83b, and 83c, respectively, from the corresponding connection point where one end of the corresponding branch line 10b, 10c, or 10d of the first line 10 and one end of the corresponding branch line 9b, 9c, or 9d of the second line 9 are connected. Because the multiple second shut-off valves 34 are located at the above positions in the second shut-off device 340, refrigerant flows are blocked in both the first path 13 and the second path 14.

[0232] Fig. Figure 13 is a schematic configuration diagram of the solenoid valve 35 with opening in the air conditioning device 104 according to embodiment 5. The arrow indicates the airflow. Fig. Figure 14 is an operating explanation diagram of the solenoid valve 35 with opening in the air conditioning device 104 according to embodiment 5 and shows an open state of the solenoid valve 35 with opening. Fig. Figure 15 is an operating diagram of the solenoid valve 35 with opening in the air conditioning device 104 according to embodiment 5 and shows a closed state of the solenoid valve 35 with opening. In the Fig. 14 and Fig. The broad arrows in Figure 15 indicate the fluid flows. The thin arrow in Figure 15 indicates the fluid flows. Fig. Figure 14 indicates the direction of an electromagnetic force. The thin arrow in Fig. 15 indicates the direction of a spring force.

[0233] As in Fig. As shown in Figure 13, the solenoid valve 35 with opening has an opening 352a configured to allow fluid to pass through it even when a valve body 352 is closed. More precisely: ... Fig. 14 and Fig. As shown in Figure 15, the solenoid valve 35 with orifice has an electromagnetic coil 350, which is cylindrical in shape, and a piston or plunger 351, which is slidably arranged along the central axis of the electromagnetic coil 350. The solenoid valve 35 with orifice has the valve body 352, which is fixed to the piston 351, and a spring 353, which is under tension in a direction in which the valve body 352 is brought into contact with a valve seat 354, which is arranged in a line 200. The orifice 352a is designed as a through-hole in the valve body 352.

[0234] In the orifice solenoid valve 35, which has the above configuration, the valve body 352 is moved away from the valve seat 354 by an electromagnetic force when energy is supplied to the electromagnetic coil 350 and it is consequently in an energized state, thereby allowing fluid to pass through the orifice solenoid valve 35, as shown in Fig. Figure 14 shows that in the solenoid valve 35 with orifice, the following applies: When no energy is supplied to the electromagnetic coil 350 and it is consequently in a de-energized state, the valve body 352 is brought into contact with the valve seat 354 by a spring force, thereby blocking the fluid flow so that it does not pass through a through-hole 354a arranged in the valve seat 354, as shown in Figure 14. Fig. Figure 15 shows that since the solenoid valve 35 is provided with the opening 352a formed in the valve body 352, fluid is allowed to pass through the solenoid valve 35 via the valve body 352. That is, the first opening and closing device 300 has a configuration that allows fluid to flow through the opening 352a, even in a state where no energy is supplied.

[0235] The air conditioning device 104 according to embodiment 5 differs from the air conditioning device 100 according to embodiment 1 by the above configuration. Blockage due to refrigerant leakage

[0236] As in Fig. As shown in Figure 12, in the event of a refrigerant leak, the air conditioning device 104 closes the first shut-off device 21 and the second shut-off device 340. Since the refrigerant flows in the first path 13 and the second path 14 are blocked when the second shut-off device 340 is closed, the first opening and closing device 300 and the second opening and closing device 310 can be either open or closed. This allows – similar to the situation described in Figure 12 – the air conditioning device 104 to close the first shut-off device 21 and the second shut-off device 340 to close the first shut-off device 310. Fig. 6 - the air conditioning device 104 separates the indoor unit 83a with refrigerant leakage and the gas branch lines 43a and the liquid branch lines 42a, which are connected to the indoor unit 83a with refrigerant leakage, functionally separating them from the other areas of the refrigerant circuit A and consequently minimizing the amount of refrigerant leakage. evacuation

[0237] Fig. Figure 16 is a schematic diagram illustrating an example of airflow during evacuation in the air conditioning device 104 according to embodiment 5. Since the air conditioning device 104 is in a de-energized state during evacuation, the first shut-off device 21 and the second shut-off device 340 are opened. Furthermore, each first opening and closing unit 30 is formed by the solenoid valve 35 opening in the first opening and closing unit 300, and consequently, the solenoid valve 35 allows fluid to pass through it in a de-energized state, as described above. Therefore, in the air conditioning device 104, evacuation can be carried out from the first path 13, similar to embodiment 1, as shown in Fig. 7 shown. Effects of the air conditioning device 104 according to embodiment 5

[0238] In the air conditioning device 104, the opening and closing device S for evacuation comprises an opening and closing device, which is the first opening and closing device 300 or the second opening and closing device 310, formed with solenoid valves with opening, and the second shut-off device 340. While the air conditioning device 104 with the configuration described above is equipped with a blocking function for a refrigerant leak, as in the case of embodiment 1, the air conditioning device 104 can ensure a path for evacuation, and consequently, its design can be improved.

[0239] The arrangement positions of the second shut-off valves 34 are not limited to those illustrated in the drawing, and the second shut-off valves 34 can be arranged as follows. Each of the second shut-off valves 34 can be arranged in each of the branch lines 10b, 10c, and 10d of the first line 10. In this case, the blocking of the second path 14 can be carried out by the second opening and closing device 310. Furthermore, each of the second shut-off valves 34 can be arranged in each of the branch lines 9b, 9c, and 9d of the second line 9. In this case, the blocking of the first path 13 can be carried out by the first opening and closing device 300. Reference symbol list 1 compressor 2 Flow switching device 3 outdoor heat exchangers 4 Actuating valves on the high-pressure side 5 Actuating valve on the low-pressure side 6 Check valve block 6a Check valve 6b Check valve 6c Check valve 6d Check valve 7 High-pressure line 8 Low-pressure line 9 second line 9a Main line 9b Branch Management 9c Branch Management 9d Branch Management 10 first line 10a Main line 10b Branch Management 10c Branch Management 10d Branch Management 11 fourth line 11a Main line 11b Branch Management 11c Branch Management 11d Branch Management 12 third line 12a Main line 12b Branch Management 12c Branch Management 12d Branch Management 13 first path 14 second path 15 third path 16 fourth path 17 first branching unit 18 second branching unit 19 first flow control device 20 second flow control device 21 first shutdown device 22 Inlet branch unit 23 Outlet merging unit 24 Refrigerant leakage area 25 Vacuum pump 30 first opening and closing unit 30a first opening and closing unit 30b first opening and closing unit 30c first opening and closing unit 31 second opening and closing unit 31a second opening and closing unit 31b second opening and closing unit 31c second opening and closing unit 32 third opening and closing unit 32a third opening and closing unit 32b third opening and closing unit 32c third opening and closing unit 33 fourth opening and closing unit 33a fourth opening and closing unit 33b fourth opening and closing unit 33c fourth opening and closing unit 34 second shut-off valve 34a second shut-off valve 34b second shut-off valve 34c second shut-off valve 35 Solenoid valve 40 Pressure Reduction Device 40a Pressure Reducing Device 40b Pressure Reduction Device 40°C pressure reduction device 41 Interior heat exchangers 41a Interior heat exchanger 41b Interior heat exchanger 41c Interior heat exchanger 42 Liquid branch line 42a Liquid branch line 42b Liquid branch line 42c Liquid branch line 43 Gas branch line 43a Gas branch line 43b Gas branch line 43c Gas branch line 50 Control 51 Control 52 Control 52a Control 52b Control 52c control 60 battery 60A battery 60b battery 60c battery 61 Battery 62a battery 62b battery 62c battery 70 Measuring manifold 70a Low-pressure side connection 70a1 Low-pressure side measuring device 70b High-pressure side connection 70b1 High-pressure side measuring device 70c side feed connection 71 High-pressure line service connection 72 Low-pressure line service connection 73 refrigerant cylinders 73a Valve 74 external valve 75 Charging hose 75a Charging hose 75b Charging hose 75c charging hose 76 external circuit 81 Outdoor unit 82 Forwarding unit 83 Indoor unit 83a Indoor unit 83b Indoor unit without refrigerant leakage 83c Indoor unit 100 air conditioning units 101 Air conditioning unit 102 Air conditioning unit 103 Air conditioning unit 104 Air conditioning unit 200 lines 300 first opening and closing device 310 second opening and closing device 320 third opening and closing device 330 fourth opening and closing device 340 second shutdown device 350 electromagnetic coil 351 pistons 352 Valve bodies 352a Opening 353 spring 354 Valve seat 354a Through hole 600 battery 620 battery A refrigerant circuit P1 Connection point S Opening and closing device S for evacuation QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2018 - 169 072 A

[0005] Cited non-patent literature

[0000] Work “Refrigeration”, published by the Japan Society of Refrigerating and Air Conditioning Engineers in November 1998

[0145]

Claims

[1] Air conditioning device capable of performing simultaneous cooling and heating operations, comprising the following: an outdoor unit with a compressor, an outdoor heat exchanger configured to exchange heat between outdoor air and refrigerant, and a flow switching device; a plurality of indoor units, each having an indoor heat exchanger configured to exchange heat between the air to be conditioned and the refrigerant; a distribution unit located between the outdoor unit and the plurality of indoor units and configured to switch a flow of refrigerant supplied from the outdoor unit to the indoor units; and a refrigerant circuit formed by connecting the outdoor unit, the majority of indoor units and the distribution unit via a refrigerant line; where the forwarding unit has the following characteristics: a first path formed by a first line and configured to allow the refrigerant to flow from the majority of indoor units to the distribution unit, a first opening and closing device, which is arranged in the first path and is configured to individually block or allow each flow of refrigerant flowing from a corresponding majority of indoor units towards the distribution unit, a second path formed by a second line and configured to allow the refrigerant to flow from the distribution unit to the majority of indoor units, a second opening and closing device, which is arranged in the second path and is configured to individually block or allow each flow of refrigerant that flows, divided from the distribution unit, towards a corresponding majority of indoor units, a third path formed by a third line and configured to allow the refrigerant to flow from the majority of indoor units to the distribution unit, a fourth path formed by a fourth line and configured to allow the refrigerant to flow from the distribution unit to the majority of indoor units, a first shut-off device configured to open in a non-powered state, thus allowing refrigerant flow in the fourth path, and to close in a power-energized state, thus blocking refrigerant flow in the fourth path, and An opening and closing device for evacuation, configured to open in a non-energy-energized state so that it allows a flow of refrigerant in at least one of the first path, the second path, the third path and the fourth path, and to close in an energy-energized state so that it blocks a flow of refrigerant in at least one of the paths. [2] Air conditioning device according to claim 1, further comprising: a battery configured to power the first shutdown device in the event of a power malfunction. [3] Air conditioning device according to claim 1 or 2, wherein the fourth line has a main line and a plurality of branch lines branching off from the main line towards the plurality of indoor units, and the first shut-off device is designed as a solenoid valve, which is arranged in the main line of the fourth line. [4] Air conditioning device according to claim 1 or 2, wherein the fourth line has a main line and a plurality of branch lines branching off from the main line towards the plurality of indoor units, and the first shut-off device is designed as a plurality of solenoid valves arranged in the plurality of branch lines of the fourth line. [5] Air conditioning device according to any one of claims 1 to 4, further comprising: a battery configured to operate the opening and closing device for evacuation in the event of a power failure. [6] Air conditioning device according to any one of claims 1 to 5, wherein one or both of the first opening and closing device and the second opening and closing device are configured to also serve as the opening and closing device for evacuation and to open in a non-powered state and to close in a power-energized state. [7] Air conditioning device according to claim 6, wherein the first opening and closing device comprises a plurality of first opening and closing units arranged according to the plurality of interior units, the second opening and closing device comprises a plurality of second opening and closing units arranged according to the plurality of interior units, and one or both of the majority of first opening and closing units and the majority of second opening and closing units are each designed as an electronic expansion valve. [8] Air conditioning device according to claim 6, wherein the first opening and closing device comprises a plurality of first opening and closing units arranged according to the plurality of interior units, the second opening and closing device comprises a plurality of second opening and closing units arranged according to the plurality of interior units, and one or both of the majority of first opening and closing units and the majority of second opening and closing units each have a configuration in which two pilot-type solenoid valves are arranged in series. [9] Air conditioning device according to any one of claims 1 to 5, further comprising: a third opening and closing device, arranged in the third path and configured to individually block or allow each flow of refrigerant flowing from a corresponding plurality of indoor units towards the distribution unit, wherein The third opening and closing device is configured to also serve as an opening and closing device for evacuation and opens when not powered and closes when powered. [10] Air conditioning device according to claim 9, wherein the third opening and closing device comprises a plurality of third opening and closing units arranged according to the plurality of interior units, and Each of the majority of third opening and closing units is designed as an electronic expansion valve or a solenoid valve. [11] Air conditioning device according to any one of claims 1 to 5, further comprising: a fourth opening and closing device, which is arranged in the fourth path and is configured to individually block or allow each flow of refrigerant flowing from the distribution unit towards a corresponding majority of indoor units, wherein the fourth opening and closing device is configured to also serve as the opening and closing device for evacuation and opens in a state not supplied with energy and closes in a state supplied with energy. [12] Air conditioning device according to claim 11, wherein the fourth opening and closing device comprises a plurality of fourth opening and closing units arranged according to the plurality of interior units, and Each of the majority of fourth opening and closing units is designed as an electronic expansion valve or a solenoid valve. [13] Air conditioning device according to any one of claims 1 to 5, wherein the first line has a main line and a plurality of branch lines that branch off from the main line towards the plurality of indoor units, the second line has a main line and a plurality of branch lines that branch off from the main line towards the plurality of indoor units, the first opening and closing device comprises a plurality of first opening and closing units arranged in the main line of the first line, the second opening and closing device comprises a plurality of second opening and closing units arranged in the main line of the second line, a second switching device is arranged which is configured to open in a non-powered state and to close in a power-energized state, the second shut-off device has a plurality of second shut-off valves, each arranged on the side of a corresponding indoor unit, at a connection point where one end of the branch line of the first line of the corresponding indoor unit and one end of the branch line of the second line of the corresponding indoor unit are connected, one or both of the majority of first opening and closing units and the majority of second opening and closing units are each designed as a solenoid valve with an opening, and The opening and closing device for evacuation comprises either the first opening and closing device or the second opening and closing device, which are designed as solenoid valves with opening, as well as the second shut-off valve. [14] Air conditioning device according to any one of claims 1 to 5, wherein the first line has a main line and a plurality of branch lines that branch off from the main line towards the plurality of indoor units, the first opening and closing device comprises a plurality of first opening and closing units, which are arranged in the plurality of branch lines of the first line and are designed as solenoid valves with opening, a second switching device is arranged which is configured to open in a non-powered state and to close in a power-energized state, the second shut-off device comprises a plurality of second shut-off valves arranged in the plurality of branch lines of the first line, in series with the plurality of the first opening and closing units, and The opening and closing device for evacuation has the first opening and closing device and the second switching-off device. [15] Air conditioning device according to any one of claims 1 to 5, wherein the second line has a main line and a plurality of branch lines that branch off from the main line towards the plurality of indoor units, the second opening and closing device comprises a plurality of second opening and closing units, which are arranged in the plurality of branch lines of the second line and are designed as solenoid valves with opening, a second switching device is arranged which is configured to open in a non-powered state and to close in a power-energized state, the second shut-off device comprises a plurality of second shut-off valves arranged in the plurality of branch lines of the second line, in series with the plurality of the second opening and closing units, and The opening and closing device for evacuation has the second opening and closing device and the second switching-off device. [16] Evacuation method for the refrigerant circuit of the air conditioning device according to any one of claims 1 to 15, wherein The evacuation is carried out by operating a vacuum pump connected to a service port located in the refrigerant circuit, in a non-powered state in which the air conditioning device is not supplied with power.

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