JPH08285393A - Air conditioner for multi-room - Google Patents

Abstract

PURPOSE: To improve a comfortable feeling in an indoor environment by a method wherein a defrosting operation period of an outdoor side heat exchanger is extended during a heating operation in a freezing cycle using non-azeotropic mixed refrigerant. CONSTITUTION: There are provided a temperature sensor 17 for sensing an inlet path temperature of an outdoor side heat exchanger 5; a solenoid valve 18; a heat exchanger device 19 for heat exchanging a high temperature gas pipe with a low temperature wet gas pipe; and a defrosting operation control means 14 for judging a frosted state in the outdoor side heat exchanger 5 and outputting a defrosting operation start time finishing signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to defrosting operation control during heating operation in a multi-room air conditioner using a non-azeotropic mixed refrigerant.

[0002]

2. Description of the Related Art As a conventional technique, Japanese Patent Laid-Open No. 1366/1991
There is a multi-room air conditioner as known from Japanese Patent Publication No. 69.

A conventional technique will be described below with reference to the drawings. In FIG. 8, 1 is an outdoor unit of a multi-room air conditioner, which comprises a variable capacity compressor 2, a four-way valve 3, an outdoor electric expansion valve 4, an outdoor heat exchanger 5, and an outdoor fan 6. Reference numerals 7a, 7b and 7c are indoor units, and the indoor electric expansion valves 8a, 8b and 8c and the indoor heat exchanger 9 respectively.
a, 9b, 9c and indoor fans 10a, 10b, 10c.

The variable capacity compressor 2 changes its capacity by changing the driving power supply frequency by the inverter 11 and changing the rotation speed. 12 is an outdoor control means, 13a, 13
b and 13c are indoor control means, and 14 is a defrosting operation control means, which calculates the value of the temperature sensor 17 attached near the inlet path refrigerant pipe of the outdoor heat exchanger 5 to determine the start / end of the defrosting operation. .

The operation of the defrosting operation control of the heating operation, which is a problem in the operation of the multi-room air conditioner configured as described above, will be described with reference to the flowchart of FIG.

In the heating operation, the indoor control means 13a, 1
A heating operation signal is output from 3b and 13c to the outdoor control means 12 (STEP 1), and the outdoor control means 12 normally operates the variable capacity compressor 2 (for example, frequency 60 Hz operation), turns on the four-way valve 3, and electrically expands the outdoor side. The valve 4 is opened normally (for example, 300 pulse opening operation), the outdoor fan 6 is turned on,
The indoor control means 13a, 13b, 13c turn on the indoor electric expansion valves 8a, 8b, 8c at the normal opening (for example, 600 pulse opening operation) and turn on the indoor fans 10a, 10b, 10c (STEP 2).

Under low outdoor temperature in winter, the outdoor heat exchanger 5
The refrigerant evaporation temperature in the room also decreases, and as a result, the outdoor heat exchanger 5
Begins to frost on the surface. Therefore, the evaporation capacity of the outdoor heat exchanger 5 also decreases, and the heating capacity of the indoor units 7a, 7b, 7c decreases, and the room temperature decreases.

At this time, the temperature sensor 17 attached near the inlet pass refrigerant pipe of the outdoor heat exchanger 5 detects the temperature of the inlet pass refrigerant pipe (STEP 3), and when it is below a predetermined temperature (for example, -5 ° C.), (STEP 4) Branch to the Y side and send a signal to the defrosting operation control means 14. With this signal, the defrosting operation control means 14 determines the start of the defrosting operation and outputs a defrosting operation start signal to the outdoor control means 12 and the indoor control means 13a, 13b, 13c. The outdoor control means 12 sets the frequency of the variable capacity compressor 2 to the maximum frequency (for example, 90 Hz) to maximize the capacity, turns off the four-way valve 3, fully opens the outdoor electric expansion valve 4, and stops the outdoor fan 6. The indoor control means includes 13a, 13b, 13c indoor electric expansion valve 8a,
8b, 8c fully open, indoor fans 10a, 10b,
10c is stopped (STEP 5).

At this time, the indoor heat exchangers 9a, 9b, 9c
Then, the increase of the refrigerant circulation amount, the indoor fans 10a, 10b,
In the indoor side heat exchangers 9a, 9b, 9c, the refrigerant is not yet in the subcooling region due to the decrease in the heat exchange capacity due to the decrease in the air flow rate of 10c, and the refrigerant is further condensed in the outdoor side heat exchanger 5 to melt the frost. Defrosting operation is performed to release the necessary heat of fusion and melt the frost. After that, the refrigerant repeats the flow of passing through the four-way valve 3 and returning to the variable capacity compressor 2 again.

During the defrosting operation, the temperature of the outdoor heat exchanger 5 is about 0 ° C. due to the melting of frost, but the temperature of the inlet pass refrigerant of the outdoor heat exchanger 5 gradually increases as defrosting progresses. To rise.

When the temperature sensor 17 detects the temperature of the refrigerant passing through the inlet of the outdoor heat exchanger 5 (STEP 6) and the temperature rises above a predetermined temperature (for example, 10 ° C.) (STEP 7),
The defrosting operation control means 14 outputs a defrosting operation end signal to the outdoor control means 12 and the indoor control means 13a, 13b, 13c, and shifts to normal control (STEP 8).

[0012]

However, in the above structure, when a non-azeotropic mixed refrigerant is used as the alternative refrigerant for the HCFC 22, there is a temperature gradient, so under the same pressure, the outdoor heat exchanger inlet path Refrigerant temperature becomes low, frost is easily formed in the outdoor heat exchanger during heating operation, and defrosting operation is frequently performed, so the capacity is reduced and the comfort of the indoor environment deteriorates. ing.

The present invention is intended to solve the above-mentioned problems, and by lengthening the cycle of the defrosting operation of the outdoor heat exchanger during the heating defrosting operation when a non-azeotropic mixed refrigerant is used, It is an object of the present invention to provide a multi-room air conditioner capable of improving comfort.

[0014]

In order to achieve this object, a multi-chamber type air conditioner of the present invention comprises a variable capacity compressor, an inverter, a four-way valve, an outdoor heat exchanger, an outdoor electric expansion valve, and an outdoor unit. An outdoor unit including a fan, an indoor heat exchanger, an indoor electric expansion valve, and a plurality of indoor units including an indoor fan,
It comprises a heat exchange unit for exchanging heat between the variable capacity compressor outlet pipe and the outdoor heat exchanger inlet pipe, a solenoid valve and a check valve connected to intermediate pipes of the variable capacity compressor and the heat exchange unit. During a heating operation, a temperature sensor attached near the outdoor heat exchanger inlet path refrigerant pipe, a defrosting operation control unit that calculates a signal from the temperature sensor and determines the start and end of the defrosting operation, and the electromagnetic The valve is always opened, and during the defrosting operation by the signal from the defrosting operation control means, the capacity of the capacity variable compressor is maximized, the outdoor electric expansion valve is maximized, and the four-way valve is , When the outdoor fan is stopped and the signal from the defrosting operation control means is the end of the defrosting operation, the outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, During defrosting operation Wherein the indoor electric expansion valve opening to stop the indoor fan and maximum opening, at the end defrosting operation, and a indoor control unit installed in the indoor unit to perform normal control.

Also, an outdoor unit consisting of a variable capacity compressor, an inverter, a four-way valve, a heat exchange fin, an outdoor heat exchanger, an outdoor electric expansion valve, an outdoor fan, an indoor heat exchanger, and an indoor electric motor. Heat exchange for exchanging heat between a plurality of indoor units consisting of expansion valves and indoor fans, the variable capacity compressor outlet pipe and the outdoor heat exchanger inlet pipe via heat exchange fins at the outdoor heat exchanger inlet A unit, a solenoid valve connected to the intermediate capacity piping of the variable capacity compressor and the heat exchange unit, a check valve, during heating operation, a temperature sensor attached near the outdoor heat exchanger inlet path refrigerant piping, Defrosting operation control means for calculating the signal from the temperature sensor to determine the start and end of the defrosting operation, and the electromagnetic valve is always opened, during defrosting operation by the signal from the defrosting operation control means, Variable pressure When the capacity of the machine is maximum, the outdoor electric expansion valve is set to the maximum opening, the four-way valve is switched, the outdoor fan is stopped, and the signal from the defrosting operation control means is the defrosting operation end. Is an outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, and similarly, during the defrosting operation, the indoor electric expansion valve opening is set to the maximum opening, and the indoor fan is stopped to perform the defrosting operation. At the end, the indoor control means installed in the indoor unit for performing normal control is provided.

An outdoor unit consisting of a variable capacity compressor, an inverter, a four-way valve, an outdoor heat exchanger, an outdoor electric expansion valve, an outdoor fan, an indoor heat exchanger, an indoor electric expansion valve,
A plurality of indoor units consisting of indoor fans, a heat exchange unit for exchanging heat between the variable capacity compressor outlet piping and the outdoor heat exchanger inlet piping, and in the intermediate capacity piping of the variable capacity compressor and the heat exchange unit. When a heating operation is performed, the temperature sensor mounted near the outdoor heat exchanger inlet path refrigerant pipe and the signal from the temperature sensor are calculated to detect the first temperature. Defrosting operation control means for outputting a defrosting start signal, outputting a defrosting operation start signal when detecting the second temperature, and outputting a defrosting operation end signal when detecting the third temperature; When the frosting start signal is detected by the signal from the frost operation control means, an opening operation signal is output to the solenoid valve control means for controlling the opening / closing operation of the solenoid valve, and when the defrosting operation end signal is detected, A closing operation signal is sent to the solenoid valve control means. When the defrosting operation start signal is detected, the capacity of the capacity variable compressor is maximized, the outdoor electric expansion valve is set to the maximum opening, the four-way valve is switched, and the outdoor fan is stopped. Then, when the signal from the defrosting operation control means is the end of the defrosting operation control, the outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, and the indoor side during the defrosting operation as well. The indoor control means is installed in the indoor unit for performing normal control when the defrosting operation control is completed by stopping the indoor fan with the electric expansion valve opening set to the maximum opening.

[0017]

According to the present invention, the variable capacity compressor outlet refrigerant (high temperature) and the outdoor heat exchanger are constructed by constantly opening the solenoid valve during the heating operation when the non-azeotropic mixed refrigerant is used. It constantly exchanges heat with the inlet refrigerant (low temperature) to keep the temperature of the inlet path refrigerant of the outdoor heat exchanger constant (for example, 2 to 5).
It is possible to delay the start of the defrosting operation while minimizing the deterioration of the heating capacity.

Further, by constantly opening the solenoid valve during the heating operation when the non-azeotropic mixed refrigerant is used, the variable capacity compressor outlet refrigerant (high temperature) and the heat exchanger fins at the outdoor heat exchanger inlet are passed. It can always exchange heat with the outdoor heat exchanger inlet refrigerant (low temperature) with high efficiency to raise the temperature of the outdoor heat exchanger inlet path refrigerant by a constant temperature (for example, 2 to 5 ° C), and minimize the decrease in heating capacity. It is possible to further delay the start of the defrosting operation while keeping the limit.

In addition, the variable capacity compressor is operated by opening the solenoid valve only when the temperature of the outdoor heat exchanger inlet pass refrigerant reaches the frosting temperature during the heating operation when the non-azeotropic mixed refrigerant is used. The outlet refrigerant (high temperature) and the outdoor heat exchanger inlet refrigerant (low temperature) can be heat-exchanged to raise the outdoor heat exchanger inlet pass refrigerant temperature by a constant temperature (for example, 2 to 5 ° C.), and the heating capacity can be increased. It is possible to delay the start of the defrosting operation without lowering it.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.
This will be described with reference to FIG. 1 and 2 are configuration diagrams of a multi-room air conditioner according to the first embodiment. FIG. 3 is an operation flowchart during defrosting operation in the same embodiment.

In FIG. 1, reference numeral 1 is an outdoor unit of a multi-room air conditioner, which comprises a variable capacity compressor 2, a four-way valve 3, an outdoor electric expansion valve 4, an outdoor heat exchanger 5, and an outdoor fan 6. ing. Reference numerals 7a, 7b and 7c are indoor units, and the indoor electric expansion valves 8a, 8b and 8c and the indoor heat exchanger 9 respectively.
a, 9b, 9c and indoor fans 10a, 10b, 10c.

The variable capacity compressor 2 changes its capacity by changing the drive power supply frequency by the inverter 11 and changing the rotation speed. 12 is an outdoor control means, 13a, 13
b and 13c are indoor control means, and 14 is a defrosting operation control means, which calculates the value of the temperature sensor 17 attached near the inlet path refrigerant pipe of the outdoor heat exchanger 5 to determine the start / end of the defrosting operation. .

Reference numeral 18 denotes a solenoid valve, which constantly performs an opening operation in response to a heating operation signal from the outdoor control means 12 during heating operation. Reference numeral 19 denotes a heat exchange unit, which is connected to a middle pipe between the outdoor electric expansion valve 4 and the outdoor heat exchanger 5, and has an inner pipe 19a as shown in FIG.
9b, an outlet pipe 19c, and a double pipe structure composed of an outer pipe 19d that is in close contact with the outside of the inner pipe 19a. A low temperature wet gas refrigerant is flown through the inner pipe 19a (a wavy line arrow),
By flowing a high temperature gas refrigerant (practical arrow) through the inlet pipe 19b, the outer pipe 19d, and the outlet pipe 19c, heat exchange between the high temperature refrigerant and the low temperature refrigerant is improved. Reference numeral 20 is a check valve that prevents the reverse flow of the refrigerant during the cooling operation.

The operation of the defrosting operation control of the heating operation, which is a problem in the operation of the multi-room air conditioner configured as described above, will be described with reference to the flowchart of FIG.

In the heating operation, the indoor control means 13a, 1
A heating operation signal is output from 3b and 13c to the outdoor control means 12 (STEP 1), and the outdoor control means 12 normally operates the variable capacity compressor 2 (for example, frequency 60 Hz operation), turns on the four-way valve 3, and electrically expands the outdoor side. The valve 4 is opened normally (for example, 300 pulse opening operation), the outdoor fan 6 is turned on,
The indoor control means 13a, 13b, 13c turn on the indoor electric expansion valves 8a, 8b, 8c at the normal opening (for example, 600 pulse opening operation) and turn on the indoor fans 10a, 10b, 10c (STEP 2).

After the above operation, the outdoor control means 12 opens the electromagnetic valve 18 (STEP 3).

Under low outside temperatures in winter, the outdoor heat exchanger 5
The refrigerant evaporation temperature in the room also decreases, and as a result, the outdoor heat exchanger 5
However, since the solenoid valve 18 is opened, the refrigerant in the outlet pipe (high temperature) of the variable capacity compressor 2 becomes the refrigerant in the inlet path pipe (low temperature) of the outdoor heat exchanger 5. Heat is exchanged via the heat exchange unit 19. Therefore, in the outdoor heat exchanger 5, the time until frost formation becomes long. After that, when the operation is continued and the temperature (low temperature) of the refrigerant in the inlet path pipe of the outdoor heat exchanger 5 exceeds the temperature (high temperature) of the refrigerant flowing from the outlet pipe of the variable capacity compressor 2, the evaporation capacity is also lowered. The room temperature is lowered due to the reduction of the heating capacity of the indoor units 7a, 7b, 7c.

At this time, the temperature sensor 17 attached in the vicinity of the inlet pass refrigerant pipe of the outdoor heat exchanger 5 detects the temperature of the inlet pass refrigerant pipe (STEP 4), and when the temperature is below a predetermined temperature (for example, -5 ° C.), (STEP 5) Branch to the Y side and send a signal to the defrosting operation control means 14. With this signal, the defrosting operation control means 14 determines the start of the defrosting operation and outputs a defrosting operation start signal to the outdoor control means 12 and the indoor control means 13a, 13b, 13c. The outdoor control means 12 sets the frequency of the variable capacity compressor 2 to the maximum frequency (for example, 90 Hz) to maximize the capacity, the four-way valve 3 is turned off, the opening degree of the outdoor electric expansion valve 4 is fully opened, and the outdoor fan 6 is stopped. The indoor control means includes 13a, 13b, 13c indoor electric expansion valve 8a,
8b, 8c fully open, indoor fans 10a, 10b,
10c is stopped (STEP6).

At this time, the indoor heat exchangers 9a, 9b, 9c
Then, the increase of the refrigerant circulation amount, the indoor fans 10a, 10b,
In the indoor side heat exchangers 9a, 9b, 9c, the refrigerant is not yet in the subcooling region due to the decrease in the heat exchange capacity due to the decrease in the air flow rate of 10c, and the refrigerant is further condensed in the outdoor side heat exchanger 5 to melt the frost. Defrosting operation is performed to release the necessary heat of fusion and melt the frost. After that, the refrigerant repeats the flow of passing through the four-way valve 3 and returning to the variable capacity compressor 2 again.

During the defrosting operation, the temperature of the outdoor heat exchanger 5 is about 0 ° C. due to the melting of frost, but the temperature of the inlet pass refrigerant of the outdoor heat exchanger 5 gradually increases as defrosting progresses. To rise.

When the temperature sensor 17 detects the temperature of the refrigerant passing through the inlet of the outdoor heat exchanger 5 (STEP 7) and the temperature rises above a predetermined temperature (for example, 10 ° C.) (STEP 8),
The defrosting operation control means 14 outputs a defrosting operation end signal to the outdoor control means 12 and the indoor control means 13a, 13b, 13c, and shifts to normal control (STEP 9).

As a result, the comfort of the indoor environment can be improved by lengthening the time until frost is formed on the outdoor heat exchanger 5 during the heating operation.

Next, a second embodiment of the present invention will be described with reference to FIGS.
Will be explained. 4 and 5 are refrigerant cycle diagrams of the multi-room air conditioner according to the second embodiment.

The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 4, 5 is an outdoor heat exchanger comprising heat exchange fins, 21 is a heat exchange unit, which is attached to the inlet side of the outdoor heat exchanger 5 and is as shown in FIG. The pipes are adhered to the heat exchange fins by welding or soldering so that the low-temperature wet gas refrigerant and the high-temperature gas refrigerant (practical arrow) flow efficiently at low cost. Reference numeral 20 is a check valve that prevents the reverse flow of the refrigerant during the cooling operation.

Since the operation is the same as that of the first embodiment, its description is omitted. As a result, the comfort of the indoor environment can be further improved by further lengthening the time until frost is formed on the outdoor heat exchanger 5 during the heating operation.

Next, a third embodiment of the present invention will be described with reference to FIGS.
Will be explained. FIG. 6 is a refrigerant cycle diagram of the multi-room air conditioner in the third embodiment, and FIG. 7 is a flowchart showing its operation.

The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 6, 12 is an outdoor control means, 13
a, 13b, 13c are indoor control means, and 14 is a defrosting operation control means, which calculates the value of the temperature sensor 17 mounted near the inlet path refrigerant pipe of the outdoor heat exchanger 5 to start frosting and defrosting operation. Determine the start and end.

Reference numeral 23 denotes a solenoid valve which performs an opening operation in response to a frosting start signal from the outdoor control means 12 and performs a closing operation in response to a defrosting operation start signal and a defrosting operation end signal during heating operation.

The operation of the defrosting operation control of the heating operation, which is a problem in the operation of the multi-room air conditioner configured as described above, will be described with reference to the flowchart of FIG.

In the heating operation, the indoor control means 13a, 1
A heating operation signal is output from 3b and 13c to the outdoor control means 12 (STEP 1), and the outdoor control means 12 normally operates the variable capacity compressor 2 (for example, frequency 60 Hz operation), turns on the four-way valve 3, and electrically expands the outdoor side. The valve 4 is opened normally (for example, 300 pulse opening operation), the outdoor fan 6 is turned on,
The indoor control means 13a, 13b, 13c turn on the indoor electric expansion valves 8a, 8b, 8c at the normal opening (for example, 600 pulse opening operation) and turn on the indoor fans 10a, 10b, 10c (STEP 2).

Under low outdoor temperature in winter, the outdoor heat exchanger 5
Also, the refrigerant evaporation temperature in the above condition decreases, and frost starts to form on the surface of the outdoor heat exchanger 5. At this time, the temperature sensor 17 attached near the inlet path refrigerant pipe of the outdoor heat exchanger 5 detects the temperature of the inlet path refrigerant pipe, and when the temperature is equal to or lower than the first predetermined temperature (for example, −2 ° C.), (STEP 3). It branches to the Y side and sends a signal to the defrosting operation control means 14. With this signal, the defrosting operation control means 14 determines the start of frost formation, and the outdoor control means 12
Outputs an opening operation signal to the solenoid valve 23, and the solenoid valve 23 performs the opening operation.

At this time, the refrigerant in the outlet pipe (high temperature) of the variable capacity compressor 2 is in the inlet path pipe (low temperature) of the outdoor heat exchanger 5.
In the outdoor heat exchanger 5, the temperature of the inlet path pipe rises by a constant value (for example, 2 to 5 ° C.) to prevent frost formation, and the heating operation is continued.
After that, when the operation is further continued, if the temperature (low temperature) of the refrigerant in the inlet path pipe of the outdoor heat exchanger 5 exceeds the temperature (high temperature) of the refrigerant flowing from the outlet pipe of the variable capacity compressor 2, the evaporation capacity also decreases. As a result, the heating capacity of the indoor units 7a, 7b, 7c decreases, and the room temperature decreases.

At this time, the temperature sensor 17 attached in the vicinity of the inlet pass refrigerant pipe of the outdoor heat exchanger 5 detects the temperature of the inlet pass refrigerant pipe (STEP 5), and when it is below the second predetermined temperature (for example, -5). C.), (STEP6) branch to the Y side, and send a signal to the defrosting operation control means 14. With this signal, the defrosting operation control means 14 judges the start of the defrosting operation, and the outdoor control means 12 and the indoor control means 13a, 13b, 13 are detected.
The defrosting operation start signal is output to c. The outdoor control means 12 sets the frequency of the variable capacity compressor 2 to the maximum frequency (for example, 90H).
z) to maximize the capacity, turn off the four-way valve 3, fully open the opening of the outdoor expansion valve 4, stop the outdoor fan 6, and the indoor control means 13a, 13b, 13c indoor expansion valves 8a, 8b. , 8c fully open, indoor fans 10a, 1
0b and 10c are stopped (STEP 7).

At this time, the indoor heat exchangers 9a, 9b, 9c
Then, the increase of the refrigerant circulation amount, the indoor fans 10a, 10b,
In the indoor side heat exchangers 9a, 9b, 9c, the refrigerant is not yet in the subcooling region due to the decrease in the heat exchange capacity due to the decrease in the air flow rate of 10c, and the refrigerant is further condensed in the outdoor side heat exchanger 5 to melt the frost. Defrosting operation is performed to release the necessary heat of fusion and melt the frost. After that, the refrigerant repeats the flow of passing through the four-way valve 3 and returning to the variable capacity compressor 2 again.

During the defrosting operation, the temperature of the outdoor heat exchanger 5 is about 0 ° C. due to the melting of frost, but the temperature of the inlet pass refrigerant of the outdoor heat exchanger 5 gradually increases as defrosting progresses. To rise.

When the temperature sensor 17 detects the temperature of the refrigerant passing through the inlet of the outdoor heat exchanger 5 (STEP 8) and the temperature rises above a predetermined temperature (for example, 10 ° C.) (STEP 9),
The defrosting operation control means 14 outputs a defrosting operation end signal to the outdoor control means 12 and the indoor control means 13a, 13b, 13c, and shifts to normal control (STEP 10).

As a result, the comfort of the indoor environment can be improved by preventing the deterioration of the capacity during the defrosting operation and prolonging the time until the frost is formed on the outdoor heat exchanger 5 during the heating operation. .

[0050]

As is apparent from the above description, the present invention provides an outdoor unit including a variable capacity compressor, an inverter, a four-way valve, an outdoor heat exchanger, an outdoor electric expansion valve, and an outdoor fan, and an indoor side. A plurality of indoor units consisting of a heat exchanger, an indoor electric expansion valve, an indoor fan, a heat exchange unit for exchanging heat between the variable capacity compressor outlet pipe and the outdoor heat exchanger inlet pipe, and the variable capacity compression Machine and a solenoid valve connected to the middle pipe of the heat exchange unit, consisting of a check valve, during heating operation, the temperature sensor installed near the outdoor heat exchanger inlet path refrigerant pipe, and the signal from the temperature sensor The defrosting operation control means for calculating the start and end of the defrosting operation and the solenoid valve are constantly opened, and the capacity of the variable capacity compressor is controlled by the signal from the defrosting operation control means during the defrosting operation. Maximum, the outdoor electric With a maximum opening of the expansion valve, switching the four-way valve, the outdoor fan is stopped,
When the signal from the defrosting operation control means is the end of the defrosting operation, the outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, and the indoor electric expansion valve during defrosting operation as well. The indoor control unit is installed in the indoor unit that controls the normal operation when the defrosting operation is completed by stopping the indoor fan with the maximum opening.

As a result, when a non-azeotropic mixed refrigerant is used as a substitute refrigerant for the HCFC 22, it is possible to prevent the frost formation cycle from being shortened due to a decrease in the refrigerant temperature of the outdoor side heat exchanger inlet path refrigerant under the same pressure due to the temperature gradient. However, by delaying the time until frost forms on the outdoor heat exchanger during heating operation while minimizing the decrease in heating capacity, the defrosting operation cycle can be extended and the comfort of the indoor environment can be improved. It is possible to provide a multi-room air conditioner using a boiling mixed refrigerant.

The present invention also includes an outdoor unit including a variable capacity compressor, an inverter, a four-way valve, an outdoor heat exchanger including a heat exchange fin, an outdoor electric expansion valve, and an outdoor fan.
A plurality of indoor units including an indoor heat exchanger, an indoor electric expansion valve, and an indoor fan, and the outdoor heat exchanger via the variable capacity compressor outlet pipe and the heat exchanger fins at the outdoor heat exchanger inlet. A heat exchange unit for exchanging heat with the inlet pipe, a solenoid valve connected to the intermediate capacity pipe of the variable capacity compressor and the heat exchange unit, a check valve, and during heating operation, the outdoor side heat exchanger inlet pass refrigerant A temperature sensor mounted in the vicinity of the pipe, a defrosting operation control unit that calculates a signal from the temperature sensor and determines the start and end of the defrosting operation, and the electromagnetic valve is always opened, and the defrosting operation control unit is operated. During the defrosting operation, the capacity of the variable capacity compressor is maximized, the outdoor electric expansion valve is set to the maximum opening, the four-way valve is switched, the outdoor fan is stopped, and the defrosting operation is performed. Message from control means If the defrosting operation is completed, the outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, and the indoor electric expansion valve opening degree during the defrosting operation as the maximum opening degree The indoor control means is installed in the indoor unit for stopping the fan and performing normal control when the defrosting operation ends.

As a result, when a non-azeotropic mixed refrigerant is used as a substitute refrigerant for the HCFC 22, it is possible to prevent the frost formation cycle from being shortened due to a decrease in the temperature of the refrigerant in the outdoor heat exchanger inlet path under the same pressure due to the temperature gradient. However, by further delaying the time to frost on the outdoor heat exchanger during heating operation while minimizing the decrease in heating capacity, the defrosting operation cycle can be extended and the comfort of the indoor environment can be further improved. A multi-room air conditioner using a non-azeotropic mixed refrigerant can be provided.

The present invention also relates to an outdoor unit including a variable capacity compressor, an inverter, a four-way valve, an outdoor heat exchanger, an outdoor electric expansion valve, an outdoor fan, an indoor heat exchanger, and an indoor electric expansion valve. , A plurality of indoor units consisting of indoor fans, a heat exchange unit for exchanging heat between the variable capacity compressor outlet pipe and the outdoor heat exchanger inlet pipe, and in the middle of the variable capacity compressor and the heat exchange unit A temperature sensor that consists of a solenoid valve and a check valve connected to the pipe and is installed near the outdoor heat exchanger inlet path refrigerant pipe during heating operation, and the signal from the temperature sensor is calculated to detect the first temperature. Defrosting operation control means for outputting a defrosting start signal when detecting the second temperature, outputting a defrosting operation starting signal when detecting the second temperature, and outputting a defrosting operation ending signal when detecting the third temperature, The message from the defrosting operation control means When the frost formation start signal is detected by the above, an opening operation signal is output to the solenoid valve control means for controlling the opening / closing operation of the solenoid valve, and when the defrosting operation end signal is detected, the solenoid valve control means is closed. When the operation signal is output and the defrosting operation start signal is detected, the capacity of the capacity variable compressor is maximized, the outdoor electric expansion valve is set to the maximum opening, and the four-way valve is switched to the outdoor fan. To stop
If the signal from the defrosting operation control means is the end of the defrosting operation control, the outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, and the indoor electric expansion during the defrosting operation. The indoor control means is installed in the indoor unit that performs normal control when the defrosting operation control is completed by stopping the indoor fan with the valve opening set to the maximum opening.

As a result, when the non-azeotropic mixed refrigerant is used as the alternative refrigerant for the HCFC 22, it is possible to prevent the frost formation cycle from being shortened due to the decrease in the refrigerant temperature of the outdoor heat exchanger inlet path under the same pressure due to the temperature gradient. The defrosting operation cycle is lengthened by increasing the time to frost formation on the outdoor heat exchanger during heating operation while preventing the deterioration of capacity due to defrosting operation, which improves comfort in the indoor environment. A multi-room air conditioner using a non-azeotropic mixed refrigerant can be provided.

[Brief description of drawings]

FIG. 1 is a refrigerant cycle diagram of a multi-room air conditioner according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part in the first embodiment of the present invention.

FIG. 3 is an operation flowchart during defrosting operation according to the first embodiment of the present invention.

FIG. 4 is a refrigerant cycle diagram of a multi-room air conditioner according to a second embodiment of the present invention.

FIG. 5 is an enlarged view of a main part in the second embodiment of the present invention.

FIG. 6 is a refrigerant cycle diagram of a multi-room air conditioner according to a third embodiment of the present invention.

FIG. 7 is an operation flowchart during defrosting operation according to the third embodiment of the present invention.

FIG. 8 is a refrigerant cycle diagram of a conventional multi-room air conditioner.

FIG. 9 is an operation flowchart during defrosting operation in the conventional multi-room air conditioner.

[Explanation of symbols]

 1 outdoor unit 2 variable capacity compressor 3 four-way valve 4 outdoor electric expansion valve 5 outdoor heat exchanger 6 outdoor fan 7a, 7b, 7c indoor unit 8a, 8b, 8c indoor electric expansion valve 10a, 10b, 10c indoor fan 11 Inverter 12 Outdoor Control Means 13a, 13b, 13c Indoor Control Means 14 Defrosting Operation Control Means 17 Temperature Sensor 18 Solenoid Valve 19 Heat Exchange Unit 20 Check Valve

Claims (3)

[Claims] 1. A variable capacity compressor, an inverter, a four-way valve,
An outdoor unit including an outdoor heat exchanger, an outdoor electric expansion valve, and an outdoor fan; a plurality of indoor units including an indoor heat exchanger, an indoor electric expansion valve, and an indoor fan; and the variable capacity compressor outlet pipe. A heat exchange unit for exchanging heat with the outdoor heat exchanger inlet pipe, a solenoid valve connected to the intermediate capacity pipe of the variable capacity compressor and the heat exchange unit, and a check valve. A temperature sensor mounted in the vicinity of the heat exchanger inlet path refrigerant pipe, a defrosting operation control unit that calculates the signal from the temperature sensor and determines the start and end of the defrosting operation, and always opens the solenoid valve, During the defrosting operation by the signal from the defrosting operation control means, the capacity of the variable capacity compressor is maximized, the outdoor electric expansion valve is set to the maximum opening, the four-way valve is switched, and the outdoor fan is stopped. Let the defrosting luck When the signal from the control means is the end of the defrosting operation, the four-way valve is returned to the outdoor control means installed in the outdoor unit for normal control, and the indoor side electric expansion valve opening degree is also maximized during the defrosting operation. When the defrosting operation is completed, the indoor fan is set to an opening degree, and when the defrosting operation is completed, the indoor unit is installed in the indoor unit, and a multi-chamber air conditioner using a non-azeotropic mixed refrigerant as a refrigerant is provided. apparatus. 2. A variable capacity compressor, an inverter, a four-way valve,
An outdoor heat exchanger consisting of heat exchange fins, an outdoor electric expansion valve, an outdoor unit consisting of an outdoor fan, and an indoor heat exchanger,
Heat exchange between a plurality of indoor units consisting of an indoor electric expansion valve and an indoor fan, the variable capacity compressor outlet pipe, and the outdoor heat exchanger inlet pipe via heat exchange fins at the outdoor heat exchanger inlet A heat exchange unit, a solenoid valve connected to the intermediate capacity piping of the variable capacity compressor and the heat exchange unit,
Defrosting operation control that consists of a check valve and that determines the start and end of defrosting operation by calculating the signal from the temperature sensor installed near the outdoor heat exchanger inlet path refrigerant pipe during heating operation and the signal from the temperature sensor Means and the solenoid valve is always opened,
During the defrosting operation by the signal from the defrosting operation control means,
The capacity of the variable capacity compressor is maximized, the outdoor electric expansion valve is maximized, the four-way valve is switched, the outdoor fan is stopped, and the signal from the defrost operation control means is a defrost operation. If it is the end, the four-way valve is returned and the outdoor control means installed in the outdoor unit that performs normal control, and the indoor electric expansion valve opening is set to the maximum opening during the defrosting operation, and the indoor fan is stopped. A multi-chamber air conditioner that includes an indoor control unit that is installed in the indoor unit that performs normal control when the defrosting operation ends and that uses a non-azeotropic mixed refrigerant as the refrigerant. 3. A variable capacity compressor, an inverter, a four-way valve,
An outdoor unit including an outdoor heat exchanger, an outdoor electric expansion valve, and an outdoor fan; a plurality of indoor units including an indoor heat exchanger, an indoor electric expansion valve, and an indoor fan; and the variable capacity compressor outlet pipe. A heat exchange unit for exchanging heat with the outdoor heat exchanger inlet pipe, a solenoid valve connected to the intermediate capacity pipe of the variable capacity compressor and the heat exchange unit, and a check valve. A temperature sensor installed near the heat exchanger inlet path refrigerant pipe and a signal from the temperature sensor are calculated, and a frosting start signal is output when the temperature is detected at the first temperature, and defrosting is performed when the second temperature is detected. When the defrosting operation control unit that outputs the operation start signal and outputs the defrosting operation end signal when the third temperature is detected and the defrosting start signal is detected by the signal from the defrosting operation control unit, Controls the opening / closing operation of the solenoid valve When an opening operation signal is output to the magnetic valve control means and a defrosting operation end signal is detected, a closing operation signal is output to the solenoid valve control means, and when the defrosting operation start signal is detected, the capacity variable The capacity of the compressor is maximum, the outdoor electric expansion valve is set to the maximum opening, the four-way valve is switched, the outdoor fan is stopped, and the signal from the defrosting operation control means is the defrosting operation control completion. In some cases, with the outdoor control means installed in the outdoor unit that returns the four-way valve and performs normal control, the indoor electric expansion valve opening is set to the maximum opening during the defrosting operation, and the indoor fan is stopped and removed. A multi-chamber air conditioner that includes an indoor control unit installed in the indoor unit that performs normal control when the frost operation control ends, and uses a non-azeotropic mixed refrigerant as the refrigerant.