JP2009121707A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of reducing costs of development and shortening development period by using an outdoor unit in a heating/cooling switching system also as an outdoor unit in a simultaneous heating/cooling system, and having sufficient commodity competitiveness. <P>SOLUTION: A first indoor unit 2 as a heating/cooling switching indoor unit and a plurality of second indoor units 3 as simultaneous heating/cooling indoor units can be operated in common by the single outdoor unit 1, and a line converting mechanism 4 for converting a first gas line L11 and a second gas line L12 of the outdoor unit for switching high and low pressures, to two fixed gas lines having fixed high and low pressures, is disposed between the second indoor units 3 and the outdoor unit 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a multi-room air conditioner that can independently switch between heating and cooling.

  What is conventionally known as a system in which air conditioning can be switched independently in each room is, for example, a package type system (also referred to as air conditioning switching system) in which one outdoor unit and one indoor unit are provided for each room. And a multi-type system (also referred to as a simultaneous heating and heating system) in which a plurality of indoor units are provided in one outdoor unit.

  As the example is described in Patent Document 1, the former basically has a configuration in which the outdoor unit and the indoor unit are connected by two refrigerant distribution lines of suction and discharge. A discharge port and a suction port of a compressor provided in the outdoor unit are connected to the two refrigerant distribution lines via a four-way valve, and the four refrigerant distribution lines are operated by operating the four-way valve. By reversing the flow direction, the refrigerant flow to the indoor unit is reversed to switch between cooling and heating.

  On the other hand, as described in Patent Document 2, an example of the latter is that the outdoor unit and the indoor unit are connected to the two lines connected to the discharge port and the suction port of the compressor, and the heat in the outdoor unit. It is connected by a total of three refrigerant distribution lines, another line connected to the liquid side of the exchanger. In this configuration, the flow directions in the two refrigerant distribution lines for suction and discharge do not change, and the flow of the refrigerant is reversed for each indoor unit by the switching means provided in each indoor unit, so that the cooling room and the heating room are simultaneously It is configured to be mixed.

As is apparent from the above, the cooling / heating switching system and the cooling / heating simultaneous system are completely different systems because the configuration of the refrigerant circuit in the outdoor unit is originally different.
JP-A-10-220923 Japanese Patent No. 2682157 Republished No. 2003-87681

  However, since the two systems having the common function of switching the cooling and heating independently in each room have completely different structures as described above, the development cost and the development period have been conventionally performed separately. In other words, waste is generated, and the expandability of the system and the degree of freedom of air conditioning design are adversely affected.

  On the other hand, as shown in Patent Document 3, a configuration in which the configuration of the refrigerant circuit in the outdoor unit can be shared is also considered. In this system, a switching valve (four-way valve) is added to the cycle configuration of the cooling / heating simultaneous outdoor unit, thereby sharing the cooling / heating simultaneous outdoor unit and the cooling / heating switching outdoor unit (heat pump). However, the piping used for the high-pressure gas line in the simultaneous cooling and heating model must be used as the low-pressure gas line when cooling the cooling / heating switching model, and the piping diameter must be increased in order to ensure the cooling capacity. For this reason, there may be cases where the product power is inferior due to the necessity of various dedicated pipes.

  Therefore, the present invention aims to share the outdoor unit in the cooling / heating switching system and the outdoor unit in the simultaneous cooling / heating system, thereby reducing development costs and shortening the development period, and has sufficient commercial competitiveness. Providing an air conditioner is the main desired issue.

That is, an air conditioner according to the present invention includes an outdoor unit, a plurality of first indoor units that are operated in a single or the same mode, a single or a plurality of second indoor units, a line conversion mechanism, and a distribution mechanism. It is. And each said part has the following structures, It is characterized by the above-mentioned.
The outdoor unit includes a liquid line through which a liquid refrigerant flows, a first gas line and a second gas line through which a gaseous refrigerant flows, a compressor that compresses and discharges the sucked gaseous refrigerant, and the compressor A high / low pressure switching mechanism for switching the connection destination of the suction port to one of the first or second gas line and switching the connection destination of the discharge port of the compressor to the other of the first or second gas line; An outdoor heat exchange unit including an expansion valve connected to the liquid line and a heat exchanger connected in series to the expansion valve, and a heat exchanger of the outdoor heat exchange unit, the first gas line or the second gas line And an outdoor heat exchange operation switching mechanism that connects either one of them in a switchable manner.
The first indoor unit includes a heat exchanger and an expansion valve connected in series, and the expansion valve is connected to the liquid line, and the heat exchanger is connected to the first gas line. Air conditioning is switched by the operation of the mechanism.
The second indoor unit includes a heat exchanger and an expansion valve connected in series, and the expansion valve is connected to the liquid line.
The line conversion mechanism is connected to the outdoor unit, and the first and second gas lines that are switched between high and low pressures by operation of the high and low pressure switching mechanism are fixed to two fixed high and low pressures. Convert to gas line.
The distribution mechanism is interposed between the second indoor unit and the line conversion mechanism, and the heat exchanger of the second indoor unit is connected to either the high-pressure side fixed gas line or the low-pressure side fixed gas line. It is connected so that it can be switched.

  With such a configuration, the indoor unit (first indoor unit) used in the cooling / heating switching system can switch between cooling and heating by setting the high / low pressure switching mechanism. In addition, each indoor unit (second indoor unit) used in the simultaneous cooling and heating system can switch heating and cooling independently by switching operation of the distribution mechanism.

  In addition, when viewed from the first indoor unit that is a cooling / heating switching indoor unit, the outdoor unit according to the present invention switches between a high-pressure gas line and a low-pressure gas line like the conventional cooling / heating switching outdoor unit. The first indoor unit can be attached to the outdoor unit in the same manner as before, including piping and the like.

  On the other hand, when viewed from the second indoor unit that is a heating and cooling simultaneous indoor unit, the outdoor unit according to the present invention forms a high-pressure side or a low-pressure side fixed gas line to which high and low pressures are fixed via a line conversion mechanism. A second indoor unit is attached to each fixed gas line via a distribution mechanism. By the way, the simultaneous indoor / cooling indoor unit is conventionally attached to a gas line to which high and low pressures are fixed via a distribution mechanism. Therefore, although the line conversion mechanism is interposed in the outdoor unit according to the present invention, the second indoor unit Can be installed in the same way as before, including piping.

Therefore, as long as the line conversion mechanism is prepared, the conventional cooling / heating switching indoor unit and the simultaneous heating / cooling indoor unit including pipes can be used as they are. In this case, there is no reduction. In addition, even an outdoor unit can be configured with a slight addition / modification of the second gas line and the piping related to it from the conventional cooling / heating switching outdoor unit, which also contributes to a reduction in development cost and development period. Can do.
Furthermore, although the operation mode of the outdoor unit, that is, the operation of the high / low pressure switching mechanism is determined by the operation mode of the first indoor unit, the indoor unit is controlled by the switching operation by the outdoor heat exchange operation switching mechanism and the expansion / contraction adjustment of the expansion valve. The optimum heat exchange function of the outdoor heat exchange unit can be adjusted according to the total load as a whole.

  The line conversion mechanism can be configured by using, for example, an active valve such as a bi-directional electromagnetic valve and a controller for controlling them in the distribution mechanism. Therefore, the configuration can be simplified and the cost can be reduced.

  As a specific mode using only the passive valve, the line conversion mechanism includes a conversion source first port and a conversion source second port connected to the first gas line and the second gas line, respectively, and the high pressure side. A conversion destination first port and a conversion destination second port respectively connected to the fixed gas line and the low pressure side fixed gas line; a first flow path connecting the conversion source first port and the conversion destination first port; A second flow path connecting the conversion source second port and the conversion destination second port; a third flow path connecting the conversion source first port and the conversion destination second port; the conversion source second port; A fourth check channel connected to the first conversion destination port; a first check valve provided on the first flow passage, for allowing only the refrigerant to flow toward the first conversion source port; and on the second flow passage. Provided at the second conversion destination A second check valve that circulates only the refrigerant that is directed to the second flow path, a third check valve that is provided on the third flow path and that circulates only the refrigerant that is directed to the conversion destination second port, and the fourth flow path. And a fourth check valve that is provided and that circulates only the refrigerant directed to the conversion source second port.

  In order to be able to perform the optimum operation according to the total load when viewed as the whole indoor unit more finely and over a wide range, and thereby to increase the degree of freedom of air conditioning design, A plurality of outdoor heat exchange units are provided in parallel, and an outdoor heat exchange operation switching mechanism is provided corresponding to each outdoor heat exchange unit, and each outdoor heat exchange operation switching mechanism can be operated independently of each other. What is doing is preferable.

  In the case where the total load related to the cooling / heating of the indoor unit is below a certain level, it is desirable to configure the functions of each outdoor heat exchange unit to be able to be stopped independently. The expansion valve of the replacement unit may be closed. In this case, it is conceivable that the refrigerant remains inside the stopped heat exchanger. However, in order to return the remaining refrigerant to the refrigerant circulation path and improve its utilization efficiency, it is necessary to correspond to the heat exchange unit in the function stop state. The outdoor heat exchange operation switching mechanism is configured such that the heat exchanger of the heat exchange unit is connected to the gas line set on the low pressure side of the first gas line or the second gas line. Just keep it. This is because the remaining refrigerant is sucked into the gas line.

  Thus, according to the present invention, the outdoor unit in the cooling / heating switching system and the outdoor unit in the cooling / heating simultaneous system can be shared (shared), and the development cost can be reduced and the development period can be shortened. In addition, existing connections including piping and the like can be used for connection to each indoor unit, and since optimal control according to the load balance of air conditioning is possible, there is no disadvantage in product power. Further, the outdoor unit according to the present invention can be configured by adding only one pipe and a corresponding valve to the conventional cooling / heating switching outdoor unit. In this respect as well, the development cost is reduced and the development period is shortened. Can contribute.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[Constitution]
The air conditioner 100 according to the present embodiment has a single outdoor unit 1, a single first indoor unit 2, a plurality of second indoor units 3, a line as schematically shown in FIG. A conversion mechanism 4 and a distribution mechanism 5 are provided.

Each part will be described.
The outdoor unit 1 includes three ports P11, P12, and P13 for refrigerant inflow and outflow, a compressor 11, a four-way valve 12 that is a high-low pressure switching mechanism, an outdoor heat exchange unit 13, and a three-way valve 14 that is an outdoor heat exchange operation switching means. It has.

  Of the three ports P11, P12, P13, one is a liquid port P13 through which liquid refrigerant flows in and out, and the other two are a first gas port P11 and a second gas port through which gaseous refrigerant flows in and out. P12. A liquid line L13 which is an internal pipe is connected to the liquid port P13, and a first gas line L11 and a second gas line L12 which are internal pipes are respectively connected to the first gas port P11 and the second gas port P12. Each is connected.

  As is well known, the compressor 11 compresses the gaseous refrigerant sucked from the suction port and discharges it from the discharge port, and various types such as a rotary type and a piston type can be used.

  The four-way valve 12 has four ports, of which the A port and the B port are connected to the suction port and the discharge port of the compressor 11 via an internal pipe, and the C port and the D port are the first port. The gas line L11 and the second gas line L12 are connected to each other. Then, the connection of the suction port of the compressor 11 is switched to either the first gas line L11 or the second gas line L12 by the movement of the internal valve body by an external command from a controller (not shown) or the like, and the compression is performed. The connection destination of the discharge port of the machine 11 can be switched to the other of the first gas line L11 or the second gas line L12.

  The outdoor heat exchange unit 13 includes a heat exchanger 131 connected in series and an electric expansion valve 132 whose opening degree can be adjusted. The expansion valve 132 is further connected to the liquid line L13, and the heat exchanger 131 is further connected to one port of the three-way valve 14 serving as heat exchange operation switching means. The remaining two ports of the three-way valve 14 communicate with the first gas line L11 and the second gas line L12, respectively, and the heat exchanger 131 causes the first gas line L11 and the second gas line L12 to move by the movement of the internal valve body by an external command. It is configured to be selectively connected to either the line L11 or the second gas line L12. In this embodiment, a plurality (two) of the outdoor heat exchange units 13 are provided in parallel, and the same number (two) of the three-way valves 14 is provided correspondingly.

  Next, the first indoor unit 2 will be described. Like the outdoor heat exchange unit 13, this is provided with a heat exchanger 21 connected in series and an electric expansion valve 22 whose opening degree can be adjusted. The expansion valve 22 is connected to the liquid port P13 of the outdoor unit 1 and the heat exchanger 21 is connected to the first gas port P11 of the outdoor unit 1 by external piping. It is configured to switch. More specifically, a controller (not shown) receives a signal from an operating means, a temperature sensor or the like (not shown) attached to the first indoor unit 2 to switch the four-way valve 12 and It is configured to set the mode.

  Similar to the first indoor unit 2, the second indoor unit 3 includes a heat exchanger 31 connected in series and an electric expansion valve 32 whose opening / closing can be adjusted. And the said expansion valve 32 is connected to the said liquid line L13 by external piping, and the heat exchanger 31 is connected to the distribution mechanism 5 mentioned later.

  The line conversion mechanism 4 is interposed between the outdoor unit 1 and the second indoor unit 3, and connects the two gas lines L11 and L12 of the outdoor unit 1 in which the high and low pressure and the refrigerant flow direction are switched to the high and low pressure and the refrigerant flow direction. Is converted into two fixed gas lines LL and LH. The high-pressure side fixed gas line LH is a flow path that communicates with the discharge side of the compressor and circulates the high-pressure gaseous refrigerant toward the distribution mechanism side. The low-pressure side fixed gas line LL is a flow path that communicates with the suction side of the compressor and circulates the low-pressure gaseous refrigerant toward the line conversion mechanism side (outdoor unit side).

  Thus, the conversion source first port P41a is connected to the first gas line via an external pipe, and the conversion destination first port P41b is connected to the low-pressure side fixed gas line LL. The conversion source second port P42a is connected to the second gas line via an external pipe, and the conversion destination second port P42b is connected to the high-pressure side fixed gas line LH.

  As the internal flow path, a first flow path L41 that connects the conversion source first port P41a and the conversion destination first port P41b, a second flow path L42 that connects the conversion source second port P42a and the conversion destination second port P42b, There are a total of four channels, a third flow path L43 connecting the conversion source first port P41a and the conversion destination second port P42b, and a fourth flow path L44 connecting the conversion source second port P42a and the conversion destination first port P41b. In each of the flow paths L41 to L44, check valves 41 to 44 for restricting the refrigerant flow direction to only one side are provided.

  The first check valve 41 is provided on the first flow path L41 so as to circulate only the refrigerant directed to the conversion source first port P41a. The second check valve 42 is provided so that only the refrigerant directed to the conversion destination second port P42b flows through the second flow path L42. The third check valve 43 is provided so that only the refrigerant directed to the conversion destination second port P42b flows through the third flow path L43. The fourth check valve 44 is provided so that only the refrigerant directed to the conversion source second port P42a flows through the fourth flow path L44.

  The line conversion mechanism 4 of the present embodiment further includes a fifth flow path L45 that allows liquid refrigerant to pass therethrough, and external connection relay ports P43a and P43b are provided at the respective ends of the fifth flow path L45. Provided. Then, one relay port P43a is connected to the liquid port P13 via an external pipe, and the other relay port P43b is connected to a distribution mechanism 5 described later.

  The distribution mechanism 5 is interposed between the second indoor unit 3 and the line conversion mechanism 4, and the heat exchanger 31 of the second indoor unit 3 is fixed to the high-pressure side fixed gas line LH or the low-pressure side fixed. The switch is connected to one of the gas lines LL in a switchable manner. Specifically, this has a plurality (two in this case) of switching units 53 provided corresponding to the respective second indoor units 3. Each switching unit 53 includes two branch channels L51 and L52, one liquid channel L53, and electromagnetic on-off valves 51 and 52 provided in the branch channels L51 and L52, respectively. One end of each branch flow path L51, L52 is connected to the heat exchanger 31 of the second indoor unit 3 via the indoor unit side connection port P55, and the other end is connected to the line conversion mechanism side connection port P51. , P52 is connected to the high-pressure side fixed gas line LH and the other is connected to the low-pressure side fixed gas line LL. The liquid flow path L53 has one end connected to the expansion valve 32 of the second indoor unit 3 via the indoor unit side connection port P54 and the other end connected to the fifth flow of the line conversion mechanism 4 via the line conversion mechanism side connection port P53. It is connected to the path L45.

[Operation]
Next, the operation of the air conditioning apparatus 100 having such a configuration will be described with reference to FIGS. In FIGS. 2 to 11, the valve in the closed state is painted in black, and the valve in the opened state is expressed in white.

[[Cooling mode]]
For example, when the first indoor unit 2 is in the cooling mode, a controller (not shown) detects this, and the four-way valve 12 of the outdoor unit 1 is in the state shown in FIGS. 2 to 6, that is, the first gas line L11 is in the compressor 11. The low pressure gas line connected to the suction side is controlled, and the second gas line L12 is controlled to be a high pressure gas line connected to the discharge side of the compressor 11. Hereinafter, the refrigerant flow and the like depending on the load state in the cooling mode will be described.

[[Cooling mode: Cooling load >> Heating load]]
For example, when a large cooling load is acting on any of the second indoor units 3, such as when the cooling load when viewed as the entire indoor unit is very large compared to the heating load (in the case of FIG. 12, pattern 1), The controller controls the three-way valve 14 to connect each outdoor heat exchanger 131 to the second gas line L12, which is a high-pressure gas line, and set all of them to function as a condenser. Further, the controller controls the on-off valves 51 and 52 of the distribution mechanism 5 to close the branch flow path L52 connected to the high-pressure side fixed gas line LH and to branch the same connected to the low-pressure side fixed gas line LL. By setting the flow path L51, all of the second indoor units 3 are set to perform a cooling action.

  The flow of the refrigerant at this time will be described with reference to FIG. 2. The high-pressure gaseous refrigerant discharged from the discharge port of the compressor 11 is introduced into each outdoor heat exchange unit 13 through the four-way valve 12 and the three-way valve 14. Then, after being liquefied to become a liquid refrigerant, it is led out from the outdoor unit 1 through the liquid line L13.

  A part of the liquid refrigerant led out from the outdoor unit 1 flows into the first indoor unit 2, is decompressed by the expansion valve 22, is vaporized by the heat exchanger 21, performs a cooling action, and then has a low pressure. It is discharged as a gaseous refrigerant. The low-pressure gaseous refrigerant returns from the first gas line L11 to the intake port of the compressor 11 via the four-way valve 12.

  On the other hand, the remaining liquid refrigerant led out from the liquid port P13 of the outdoor unit 1 passes through the fifth flow path L45 of the line conversion mechanism 4 and the liquid flow path L53 of the distribution mechanism 5, and is introduced into each second indoor unit 3. The And after decompressing with the expansion valve 32 of each of these 2nd indoor units 3, it evaporates with the heat exchanger 31, performs a cooling action, and is discharged | emitted from the 2nd indoor unit 3. The discharged low-pressure gaseous refrigerant flows into the low-pressure side fixed gas line LL through the open branch flow path L51 in the distribution mechanism 5. Then, the first flow path L41 of the line conversion mechanism 4 passes through the first gas line L11, merges with the low-pressure gaseous refrigerant from the first indoor unit 2, and returns to the suction port of the compressor 11.

[[Cooling mode: Cooling load> Heating load]]
For example, when one of the second indoor units 3 has a relatively large cooling load and the other has a small heating load, the cooling load when viewed as the whole indoor unit is slightly larger than the heating load (FIG. 12, pattern 2 In the case), the controller controls one of the three-way valves 14 and connects one outdoor heat exchanger 131 to the second gas line L12, which is a high-pressure gas line. For the vessel 131, the corresponding expansion valve 132 is closed to inhibit the flow of the refrigerant, and the heat exchange function is stopped. Furthermore, in this embodiment, the controller controls the other three-way valve 14 to connect one end of the heat exchanger 131 in a function stop state to the first gas line L11 that is a low-pressure gas line. This is because the residual refrigerant in the heat exchanger 131 is sucked to improve the refrigerant utilization efficiency. Further, as shown in FIG. 3, the controller controls the open / close valves 51 and 52 of the distribution mechanism 5 to reverse the open / close states of the switching units 53 so that the refrigerant flows in the second indoor units 3. It sets so that it may mutually become reverse and one 2nd indoor unit 3 performs cooling, and the other performs a heating effect | action.

  As is apparent from FIG. 3, the high-pressure gaseous refrigerant exiting from the discharge port of the compressor 11 passes through the four-way valve 12 and then partially flows into the outdoor heat exchanger 131 from one of the three-way valves 14. Then, it is condensed and liquefied, and is led out from the outdoor unit 1 through the liquid line L13.

  The liquid refrigerant derived from the liquid port P13 is a low-pressure gas line after a part of the liquid refrigerant is introduced into the first indoor unit 2 for vaporization and performs a cooling action, as in the case of the pattern 1 (FIG. 2). The first gas line L11 passes through the four-way valve 12 and returns to the suction port of the compressor 11. Further, the remaining liquid refrigerant passes through the fifth flow path L45 of the line conversion mechanism 4 and the liquid flow path L53 of the distribution mechanism 5, and is introduced into one second indoor unit 3. Then, after vaporizing in the second indoor unit 3 and performing the cooling action, the low pressure side fixed gas line LL, the first flow path L41 of the line conversion mechanism 4 and the first gas line L11 of the outdoor unit 1 are connected from the distribution mechanism 5 to this. In order, it returns to the suction port of the compressor 11.

  On the other hand, the remaining high-pressure gaseous refrigerant that has passed through the four-way valve 12 is led out from the outdoor unit 1 through the second gas line L12, passes through the second flow path L42 of the line conversion mechanism 4, and passes through the high-pressure side fixed gas line LH. Flow into. And it passes through the branch flow path L52 of the distribution mechanism 5, is introduced into the other second indoor unit 3, and condenses and liquefies while performing a heating operation with the heat exchanger. This liquid refrigerant merges with the liquid refrigerant flowing from the liquid port P13 in the liquid flow path L53 of the distribution mechanism 5, and flows into the second indoor unit 3 in the cooling mode.

  Depending on the heating / cooling load balance between the first indoor unit 2 and the second indoor unit 3, the flow of the liquid refrigerant in the fifth flow path L45 in the line conversion mechanism 4 may be as described above with reference to the dotted arrow in FIG. Is reversed and the liquid refrigerant flowing out from the other second indoor unit 3 passes through the fifth flow path L45 of the line conversion mechanism 4 and then merges with the liquid refrigerant derived from the liquid port P13. 2 may flow into

[[Cooling mode: Cooling load ≒ Heating load]]
When the cooling load and the heating load of the indoor unit are almost balanced (in the case of FIG. 12 and pattern 3), as shown in FIG. 4, the controller closes each expansion valve 132 of the outdoor unit 1 and all the outdoor heats. The function of the exchanger 131 is stopped, and each three-way valve 14 is controlled to connect one end of each outdoor heat exchanger 131 to the first gas line L11 that is a low-pressure gas line. This is because the refrigerant remaining in the outdoor heat exchanger 131 is sucked in like the pattern 2 to improve the refrigerant utilization efficiency. Further, the controller controls the open / close valves 51 and 52 of the distribution mechanism 5 so that the switching states of the switching units 53 are reversed so that the refrigerant flows in the second indoor units 3 are reversed. The second indoor unit 3 is set to be heated and the other is set to be cooled.

  Therefore, as is clear from FIG. 4, all the high-pressure gaseous refrigerant that has exited from the discharge port of the compressor 11 is led out from the outdoor unit 1 through the four-way valve 12 and the second gas line L12, and the line conversion mechanism 4. And flows into the high-pressure side fixed gas line LH via the second flow path L42. And it passes through the branch flow path L52 of the distribution mechanism 5, is introduced into one second indoor unit 3, condenses and liquefies in the heat exchanger 31, and performs a heating action. After the refrigerant liquefied here flows into the liquid flow path L53 of the distribution mechanism 5, a part of the refrigerant flows into the heat exchanger 31 of the other second indoor unit 3 from the expansion valve 32 side, and is vaporized there. Operates air conditioning. Then, the distribution mechanism 5 returns to the suction port of the compressor 11 through the low pressure side fixed gas line LL, the first flow path L41 of the line conversion mechanism 4, the first gas line L11 of the outdoor unit 1, and the four-way valve 12 in this order. The remaining liquid refrigerant passes through the fifth flow path L45 of the line conversion mechanism 4 and is guided to the first indoor unit 2 to evaporate and perform a cooling action, and then the first gas line L11 which is a low-pressure gas line. To the suction port of the compressor 11 again through the four-way valve 12.

[[Cooling mode: Cooling load <Heating load]]
For example, when one of the second indoor units 3 is a large heating load and the other is a small cooling load, the heating load when viewed as the whole indoor unit is slightly larger than the cooling load (in the case of FIG. 12, pattern 4), As shown in FIG. 5, the controller controls one of the three-way valves 14 to connect one outdoor heat exchanger 131 to a first gas line L11 that is a low-pressure gas line, and this is used as an evaporator. Further, as in Pattern 2, the other heat exchanger 131 is blocked by the corresponding expansion valve 132 to inhibit the flow of the refrigerant to stop its heat exchange function, and the corresponding three-way valve 14 is By controlling, one end of the other outdoor heat exchanger 131 is connected to the first gas line L11, which is a low-pressure gas line, to improve the refrigerant utilization efficiency. Further, the controller controls the on-off valves 51 and 52 of the distribution mechanism 5 so that the refrigerant flows in the respective second indoor units 3 are opposite to each other, with one second indoor unit 3 heating and the other cooling. Set as follows.

  Thus, as is apparent from FIG. 5, all the high-pressure gaseous refrigerant discharged from the discharge port of the compressor 11 is led out from the outdoor unit 1 through the four-way valve 12 and the second gas line L12, and the line conversion mechanism 4 And flows into the high-pressure side fixed gas line LH via the second flow path L42. And it passes through the branch flow path L52 of the distribution mechanism 5, is introduced into one second indoor unit 3, condenses and liquefies in the heat exchanger, and performs a heating action. After the refrigerant liquefied here flows into the liquid flow path L53 of the distribution mechanism 5, a part of the refrigerant flows into the heat exchanger 31 in the other second indoor unit 3 from the expansion valve 32 side, and is vaporized there. Operates air conditioning. Then, the distribution mechanism 5 returns to the suction port of the compressor 11 through the low pressure side fixed gas line LL, the first flow path L41 of the line conversion mechanism 4, the first gas line L11 of the outdoor unit 1, and the four-way valve 12 in this order. The remaining liquid refrigerant passes through the fifth flow path L45 of the line conversion mechanism 4 and then branches further, and a part thereof is guided to the first indoor unit 2 and the rest is guided to one outdoor heat exchange unit 13. And after vaporizing all, it returns to the suction port of the compressor 11 through the four-way valve 12 from the 1st gas line L11 which is a low pressure gas line.

[[Cooling mode: Cooling load << Heating load]]
When all of the second indoor units 3 have a large heating load, the heating load when viewed as the whole indoor unit is much larger than the cooling load (in the case of FIG. 12, pattern 5), as shown in FIG. In addition, the controller controls each three-way valve 14 to connect all the outdoor heat exchangers 131 to the first gas line L11 which is a low-pressure gas line, which serve as an evaporator, and the on-off valve 51 of the distribution mechanism 5. , 52 are closed, the branch flow path L51 connected to the low pressure side fixed gas line LL is closed, and the branch flow path L52 connected to the high pressure side fixed gas line LH is opened.

  Thus, as is apparent from FIG. 6, all of the high-pressure gaseous refrigerant exiting from the discharge port of the compressor 11 is led out from the outdoor unit 1 through the four-way valve 12 and the second gas line L12, and then the line It flows into the high-pressure side fixed gas line LH via the second flow path L42 of the conversion mechanism 4. And it passes through the branch flow path L52 of the distribution mechanism 5, is introduced into each 2nd indoor unit 3, is condensed and liquefied by those heat exchangers 31, and performs a heating effect | action. The liquefied refrigerant flows into the liquid flow path L53 of the distribution mechanism 5, passes through the fifth flow path L45 of the line conversion mechanism 4, and a part thereof is the first indoor unit 2, and the rest is each outdoor heat exchange unit 13. Led to. After vaporization, they merge and return from the first gas line L11, which is a low-pressure gas line, to the intake port of the compressor 11 via the four-way valve 12.

[[Heating mode]]
When the first indoor unit 2 is set to the heating mode, the controller detects this, and the four-way valve 12 of the outdoor unit 1 is connected to the state shown in FIGS. 7 to 11, that is, the first gas line L11 is connected to the discharge side of the compressor 11. And the second gas line L12 is controlled to be a low pressure gas line connected to the suction side of the compressor 11. In addition, although the flow of the refrigerant | coolant etc. by the state of the load in heating mode are demonstrated below, description may be simplified about the part which has an operation | movement common with the said air_conditioning | cooling mode.

[[Heating mode: Heating load >> Cooling load]]
For example, when a large heating load is acting on any of the second indoor units 3 and the heating load when viewed as the whole indoor unit is very large compared to the cooling load (in the case of FIG. 12, pattern 6), 7, the controller controls the three-way valve 14 to connect each outdoor heat exchanger 131 to the second gas line L12, which is a low-pressure gas line, and set all of them to function as an evaporator. To do. Further, the controller controls the on-off valves 51 and 52 of the distribution mechanism 5 to open the branch flow path L52 connected to the high-pressure side fixed gas line LH and to branch to the low-pressure side fixed gas line LL. The flow path L51 is closed.

Now, all the high-pressure gaseous refrigerant that has come out of the discharge port of the compressor 11 flows out of the outdoor unit 1 through the four-way valve 12 and the first gas line L11.
Thereafter, a part of the high-pressure gaseous refrigerant is led to the first indoor unit 2 and performs a heating operation by condensing, and then becomes a liquid refrigerant and is reintroduced into the outdoor unit 1 from the liquid port P13. And it evaporates in each outdoor heat exchange unit 13, becomes a low-pressure gaseous refrigerant, and returns to the suction port of the compressor 11 through the three-way valve 14 and the four-way valve 12.

  On the other hand, the remainder of the high-pressure gaseous refrigerant derived from the outdoor unit 1 flows into the high-pressure side fixed gas line LH via the third flow path L43 of the line conversion mechanism 4 by the action of the check valves 41 and 43. Then, after passing through the branch flow path L52 of the distribution mechanism 5 and being introduced into each second indoor unit 3 and performing a heating action, the liquid refrigerant is discharged from the liquid flow path L53 of the distribution mechanism 5. After that, it merges with the liquid refrigerant from the first indoor unit 2 through the fifth flow path L45 of the line conversion mechanism 4, evaporates in the outdoor heat exchange unit 13, and becomes a low-pressure gaseous refrigerant at the suction port of the compressor 11. Return.

[[Heating mode: Heating load> Cooling load]]
For example, when one of the second indoor units 3 is a large heating load and the other is a small cooling load, when the heating load when viewed as the whole indoor unit is slightly larger than the cooling load (in the case of FIG. 12, pattern 7), As shown in FIG. 8, the controller controls one of the three-way valves 14 to connect one outdoor heat exchanger 131 to the second gas line L12, which is a low-pressure gas line, and this is used as an evaporator. In addition, for the other heat exchanger 131, the corresponding expansion valve 132 is closed to inhibit the flow of the refrigerant, the heat exchange function is stopped, and the corresponding three-way valve 14 is controlled, One end of the other outdoor heat exchanger 131 is connected to the low-pressure second gas line L12 to improve the refrigerant utilization efficiency. Further, the controller controls the on-off valves 51 and 52 of the distribution mechanism 5 so that the refrigerant flows in the respective second indoor units 3 are opposite to each other, with one second indoor unit 3 heating and the other cooling. Set as follows.

  Now, as is clear from FIG. 8, all the high-pressure gaseous refrigerant exiting from the discharge port of the compressor 11 flows out of the outdoor unit 1 through the first gas line L11 that is a high-pressure gas line.

  A part of the refrigerant is introduced into the first indoor unit 2 to condense and perform a heating operation, and then becomes a liquid refrigerant from the liquid port P13 of the outdoor unit 1 through the expansion valve 132 and one of the outdoor heat exchangers 131. Flow into. Then, it evaporates to become a low-pressure gaseous refrigerant, and returns to the suction side of the compressor 11 via the three-way valve 14 and the four-way valve 12.

  On the other hand, the remainder of the high-pressure gaseous refrigerant flows into the line conversion mechanism 4, flows through the third flow path L43 by the function of the check valves 41 and 43, and is guided to the high-pressure side fixed gas line LH. Furthermore, it flows into one 2nd indoor unit 3 through one branch flow path L52 of the distribution mechanism 5, from there, it condenses and liquefies, performing a heating effect | action. The liquefied refrigerant branches off in the liquid flow path L53 of the distribution mechanism 5, and part of the refrigerant flows into the fifth flow path L45 of the line conversion mechanism 4 and merges with the liquid refrigerant from the first indoor unit 2. The remaining liquid refrigerant flows into the other second indoor unit 3, becomes a low-pressure gaseous refrigerant through cooling, and then flows into the line conversion mechanism 4 via the distribution mechanism 5 and the low-pressure side fixed gas line LL. . Then, the check valves 41 and 44 act to flow into the second gas line L12 of the outdoor unit 1 from the fourth flow path L44 and return to the suction side of the compressor 11 through the four-way valve 12.

  In addition, depending on the load balance of the air conditioning between the 2nd indoor units 3, the flow of the liquid refrigerant | coolant in the 5th flow path L45 of the line conversion mechanism 4 may become reverse as shown to the dotted line of FIG.

[[Heating mode: Heating load ≒ Cooling load]]
When the cooling load and the heating load of the indoor unit are substantially balanced (in the case of FIG. 12 and pattern 8), as shown in FIG. 9, the controller closes each expansion valve of the outdoor unit 1 and performs all outdoor heat exchange. In addition to stopping the function of the vessel, each one-way valve 14 is controlled so that one end of each outdoor heat exchanger is connected to the second gas line L12, which is a low-pressure gas line. Plan. Further, the controller controls the open / close valves 51 and 52 of the distribution mechanism 5 so that the open / close states of the switching units 53 are reversed so that the refrigerant flows in the second indoor units 3 are reversed. The second indoor unit 3 is set to be heated and the other is set to be cooled.

Now, as is clear from FIG. 9, all of the high-pressure gaseous refrigerant that has exited from the discharge port of the compressor 11 flows out of the outdoor unit 1 through the first gas line L11 that is a high-pressure gas line.
A part of the liquid is introduced into the first indoor unit 2 to condense and performs a heating operation, and then becomes a liquid refrigerant via the fifth flow path L45 of the line conversion mechanism 4 and the liquid flow path of the distribution mechanism 5. Flows into L53.

  The remaining high-pressure gaseous refrigerant flows into the line conversion mechanism 4, flows through the third flow path L43 by the function of the check valves 41 and 43, and is guided to the high-pressure side fixed gas line LH. Furthermore, it flows into one 2nd indoor unit 3 through one branch flow path L52 of the distribution mechanism 5, from there, it condenses and liquefies, performing a heating effect | action.

  The liquefied refrigerant flows into the liquid flow path L53 of the distribution mechanism 5, merges with the liquid refrigerant that has flowed in through the fifth flow path L45, and is introduced into the other second indoor unit 3. Then, after performing a cooling action to become a low-pressure gaseous refrigerant, it returns to the line conversion mechanism 4 via the distribution mechanism 5 and the low-pressure side fixed gas line LL. The low-pressure gaseous refrigerant that has flowed into the line conversion mechanism 4 flows into the second gas line L12 of the outdoor unit 1 from the fourth flow path L44 by the action of the check valves 41 and 44, and the compressor 11 via the four-way valve 12. Return to the suction side.

[[Heating mode: Heating load <Cooling load]]
For example, when one of the second indoor units 3 is a small heating load and the other is a large cooling load, when the heating load when viewed as the whole indoor unit is a little smaller than the cooling load (in the case of FIG. 12, pattern 9), As shown in FIG. 10, the controller controls one of the three-way valves 14 to connect one outdoor heat exchanger 131 to a first gas line L11 that is a high-pressure gas line, and this is used as a condenser. In addition, for the other heat exchanger 131, the corresponding expansion valve 132 is closed to inhibit the flow of the refrigerant, the heat exchange function is stopped, and the corresponding three-way valve 14 is controlled, One end of the other outdoor heat exchanger 131 is connected to the second gas line L12 to improve the refrigerant utilization efficiency by sucking the remaining refrigerant. Further, the controller controls the on-off valves 51 and 52 of the distribution mechanism 5 so that the refrigerant flows in the respective second indoor units 3 are opposite to each other, with one second indoor unit 3 heating and the other cooling. Set as follows.

  Now, as is clear from FIG. 10, a part of the high-pressure gaseous refrigerant exiting from the discharge port of the compressor 11 flows out of the outdoor unit 1 through the first gas line L11 which is a high-pressure gas line. The remainder is condensed in one outdoor heat exchanger 131 and becomes a liquid refrigerant and flows out of the outdoor unit 1 through the liquid port P13.

  A part of the high-pressure gaseous refrigerant that has flowed out of the outdoor unit 1 from the first gas line L11 is introduced into the first indoor unit 2 to condense and perform a heating operation, and then becomes a liquid refrigerant. The liquid refrigerant merges with the liquid refrigerant condensed in the outdoor heat exchanger 131 described above, and flows into the liquid flow path L53 of the distribution mechanism 5 through the fifth flow path L45 of the line conversion mechanism 4.

  The remaining high-pressure gaseous refrigerant flows through the third flow path L43 by the check valves 41 and 43 in the line conversion mechanism 4 and is guided to the high-pressure side fixed gas line LH. And it flows into one 2nd indoor unit 3 through one branch flow path L52 of the distribution mechanism 5, condenses there, and is liquefied, performing a heating effect | action.

  The liquefied refrigerant flows into the liquid flow path L53 of the distribution mechanism 5, merges with the liquid refrigerant that has flowed in through the fifth flow path L45, and is introduced into the other second indoor unit 3. Then, after performing a cooling action to become a low-pressure gaseous refrigerant, it returns to the line conversion mechanism 4 via the distribution mechanism 5 and the low-pressure side fixed gas line LL. The low-pressure gaseous refrigerant that has flowed into the line conversion mechanism 4 flows into the second gas line L12 of the outdoor unit 1 from the fourth flow path L44 by the action of the check valves 41 and 44, and the compressor 11 via the four-way valve 12. Return to the suction side.

[[Heating mode: Heating load << Cooling load is large]]
When the cooling load when viewed as the whole indoor unit is very large compared to the heating load, such as when all the second indoor units 3 have a large cooling load (FIG. 12, pattern 10), as shown in FIG. The controller controls each three-way valve 14 to connect each outdoor heat exchanger 131 to the first gas line L11 that is a high-pressure gas line, and these are used as condensers. Further, the controller controls the on-off valves 51 and 52 of the distribution mechanism 5 to control the flow of the refrigerant in each second indoor unit 3 so that each second indoor unit 3 is cooled.

  Now, as is clear from FIG. 11, a part of the high-pressure gaseous refrigerant discharged from the discharge port of the compressor 11 is introduced into the first indoor unit 2 through the first gas line L11 which is a high-pressure gas line. It is condensed and becomes a liquid refrigerant after heating. The remainder is condensed in each outdoor heat exchange unit 13 and becomes a liquid refrigerant and flows out of the outdoor unit 1 through the liquid port P13.

  These liquid refrigerants merge to flow into the line conversion mechanism 4 and are introduced into the liquid flow path L53 of the distribution mechanism 5 through the fifth flow path L45. And it flows in into each 2nd indoor unit 3 from the expansion-valve 32 side, vaporizes and performs the air_conditioning | cooling effect | action, It is discharged | emitted as a low-pressure gaseous refrigerant. This low-pressure gaseous refrigerant is introduced into the line conversion mechanism 4 via the other branch flow path L51 of the distribution mechanism 5, and the second gas of the outdoor unit 1 is passed through the fourth flow path L44 by the action of the check valves 41 and 44. It flows into the line L12. Then, it returns to the suction side of the compressor 11 through the four-way valve 12.

[effect]
Therefore, with such a configuration, the indoor unit (first indoor unit 2) used in the cooling / heating switching system can switch between cooling and heating by setting the four-way valve 12. In addition, each indoor unit (second indoor unit 3) used in the simultaneous cooling and heating system can switch heating and cooling independently by switching operation of the distribution mechanism 5.

  In addition, when viewed from the first indoor unit 2 that is a cooling / heating switching indoor unit, the outdoor unit 1 switches between a high-pressure gas line and a low-pressure gas line in the same manner as a conventional cooling / heating switching outdoor unit. The first indoor unit 2 including pipes and the like can be attached to the machine in the same manner as before.

  On the other hand, when viewed from the second indoor unit 3 that is a heating and cooling simultaneous indoor unit, the outdoor unit 1 forms a high-pressure side or a low-pressure side fixed gas line LL to which high and low pressures are fixed via the line conversion mechanism 4. The fixed gas lines LL and LH are attached via the distribution mechanism 5. By the way, the simultaneous indoor unit with cooling and heating is conventionally attached to a gas line to which high and low pressures are fixed via a distribution mechanism. Therefore, although the line conversion mechanism 4 is interposed in the outdoor unit 1, the second indoor unit 3 Can be installed in the same way as before, including piping.

  Therefore, as long as the line conversion mechanism 4 is prepared, the conventional cooling / heating switching indoor unit and the simultaneous heating / cooling indoor unit including pipes and the like can be used as they are. There is no reduction in power. Further, since the outdoor unit 1 can be configured with a slight addition / modification of the second gas line L12 and the piping related thereto based on the conventional cooling / heating switching outdoor unit, the development cost and the It can contribute to the reduction of the development period.

  Furthermore, although the operation mode of the outdoor unit 1, that is, the operation of the four-way valve 12, is determined by the operation mode of the first indoor unit 2, the entire indoor unit is controlled by the switching operation by the three-way valve 14 and the expansion / contraction adjustment of the expansion valve 132. As a result, the optimum heat exchange function of the outdoor heat exchange unit 13 can be adjusted according to the total load.

In particular, in this embodiment, a plurality of outdoor heat exchange units 13 are provided in parallel, an outdoor heat exchange operation switching mechanism is provided corresponding to each outdoor heat exchange unit 13, and each three-way valve 14 operates independently of each other. Therefore, the optimum operation according to the total load when viewed as the whole indoor unit can be performed more finely and over a wide range.
And by the above, since the cooling / heating switching indoor unit 2 and the simultaneous heating / cooling indoor unit 3 can be mixed and an operation corresponding to a wide range of air conditioning loads is possible, the degree of freedom in air conditioning design can be expanded.

The present invention is not limited to the above embodiments.
For example, the line conversion mechanism can also be configured by using an active valve such as a bidirectional electromagnetic valve and a controller for controlling them in the distribution mechanism. Further, the switching mechanism such as a three-way valve or a four-way valve is not limited to this type of valve. Three or more second indoor units may be provided, and there may be a plurality of first indoor units as long as the cooling / heating mode is always operated in the same mode.
In addition, it goes without saying that the present invention can be variously modified without departing from the spirit of the present invention.

The circuit diagram which shows the outline | summary of the air conditioning apparatus which concerns on one Embodiment of this invention. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 1) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 2) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 3) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 4) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 5) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 6) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 7) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 8) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 9) of the air conditioning apparatus in the embodiment. The circuit diagram which displayed the refrigerant | coolant distribution direction which shows operation | movement (pattern 10) of the air conditioning apparatus in the embodiment. The pattern table | surface which displayed the function of the heat exchanger in each operation pattern of the air conditioning apparatus in the embodiment.

Explanation of symbols

100: Air conditioner 100
DESCRIPTION OF SYMBOLS 1 ... Outdoor unit 2 ... 1st indoor unit 3 ... 2nd indoor unit 4 ... Line conversion mechanism 5 ... Distribution mechanism L13 ... Liquid line L11 ... 1st gas line L12 ... Second gas line 11 ... Compressor 11
12 ... High-low pressure switching mechanism (four-way valve)
13 ... Outdoor heat exchange unit 14 ... Outdoor heat exchange operation switching mechanism (three-way valve)
LH: High pressure side fixed gas line LL ... Low pressure side fixed gas line P41a ... Conversion source first port P42a ... Conversion source second port P41b ... Conversion destination first port P42b ... Conversion Previous second ports L41 to L45 ... 1st flow path to 5th flow paths 41 to 44 ... 1st check valve to 4th check valve P43a, P43b ... Relay port

Claims (4)

An outdoor unit, a plurality of first indoor units operated in a single or the same mode, a single or a plurality of second indoor units, a line conversion mechanism, and a distribution mechanism,
The outdoor unit is
A liquid line through which a liquid refrigerant flows;
A first gas line and a second gas line through which a gaseous refrigerant flows;
A compressor for compressing and discharging the sucked gaseous refrigerant;
High / low pressure switching the connection destination of the suction port of the compressor to one of the first or second gas line and switching the connection destination of the discharge port of the compressor to the other of the first or second gas line A switching mechanism;
An outdoor heat exchange unit comprising an expansion valve capable of controlling the flow rate connected to the liquid line and a heat exchanger connected in series to the expansion valve;
An outdoor heat exchange operation switching mechanism that connects either the first gas line or the second gas line to the heat exchanger of the outdoor heat exchange unit so as to be switchable, and
The first indoor unit is:
A heat exchanger and an expansion valve connected in series are provided, the expansion valve is connected to the liquid line, and the heat exchanger is connected to the first gas line. It ’s a replacement,
The second indoor unit is
A heat exchanger and an expansion valve connected in series are provided, and the expansion valve is connected to the liquid line.
The line conversion mechanism is
The first and second gas lines connected to the outdoor unit and switched between high and low pressures by the operation of the high and low pressure switching mechanism are converted into two fixed gas lines to which the high and low pressures are fixed. And
The distribution mechanism is:
It is interposed between the second indoor unit and the line conversion mechanism, and the heat exchanger of the second indoor unit can be switched to either the high pressure side fixed gas line or the low pressure side fixed gas line. An air conditioner characterized by being connected. The line conversion mechanism is
A conversion source first port and a conversion source second port respectively connected to the first gas line and the second gas line;
A conversion destination first port and a conversion destination second port respectively connected to the high-pressure side fixed gas line and the low-pressure side fixed gas line;
A first flow path connecting the conversion source first port and the conversion destination first port;
A second flow path connecting the conversion source second port and the conversion destination second port;
A third flow path connecting the conversion source first port and the conversion destination second port;
A fourth flow path connecting the conversion source second port and the conversion destination first port;
A first check valve that is provided on the first flow path and circulates only the refrigerant directed to the conversion source first port;
A second check valve that is provided on the second flow path and that circulates only the refrigerant directed to the conversion destination second port;
A third check valve that is provided on the third flow path and distributes only the refrigerant directed to the conversion destination second port;
The air conditioner according to claim 1, further comprising: a fourth check valve provided on the fourth flow path and configured to circulate only the refrigerant directed to the conversion source second port.   The air conditioner according to claim 1 or 2, wherein a plurality of the outdoor heat exchange units are provided in parallel, and an outdoor heat exchange operation switching mechanism capable of operating independently from each other is provided corresponding to each outdoor heat exchange unit. . The expansion valve of the outdoor heat exchange unit can be closed,
The heat exchange function of any or all of the outdoor heat exchange units is configured so as to be stopped by closing the expansion valve, and the outdoor heat exchange operation switching mechanism corresponding to the heat exchange unit in the function stop state includes the heat exchange function. The air conditioner according to claim 3, wherein the heat exchanger of the exchange unit is configured to be connected to a gas line set on the low pressure side of the first gas line or the second gas line.