JPH09318164A - Air conditioner and assembling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an additional charge of refrigerant accompanied by connection of a long pipe unnecessary by using a connecting member as well as a fixed throttled member when the piping connecting member for connecting liquid lines has a length not less than a specified length. SOLUTION: When a liquid side pipe line 12 for connecting a liquid line to a liquid line has a length not less than a specified length set in advance, the liquid lines are connected to each other by the liquid side pipe line 12 and a pipe line 15 having a capillary tube 14 as a fixed throttled member from an outdoor unit 6 side having an expansion valve 4. When the liquid side pipe line 12 for connecting the liquid pipe lines to each other has a length not more than the specified length set in advance, the pipe line 15 is not used and only the liquid side pipe line 12 is used. In this structure pressure of refrigerant which has been condensed and liquefied in an indoor heat exchanger of an indoor unit 7 is once reduced by the capillary tube 14 and further reduction of pressure is effected by the expansion valve 4. Therefore, the liquid side pipe line 12 between the capillary tube 14 and the expansion valve 4 is filled with the refrigerant in two phase. Addition of the refrigerant becomes unnecessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, for a system configuration that does not require addition of an amount of refrigerant even when an air conditioner is connected to a long pipe, and for controlling an expansion valve opening degree and a compressor rotation speed. The present invention relates to a possible air conditioner and an assembling method thereof.

[0002]

2. Description of the Related Art FIG. 8 is a system configuration diagram of a conventional air conditioner.

In the figure, 1 is a compressor, 2 is a four-way valve for switching between heating and cooling cycles, 3 is an outdoor heat exchanger, 4 is an expansion valve, 5 is an accumulator, and these components are provided in an outdoor unit 6. ing. The indoor unit 7 includes an indoor heat exchanger 8 and a room temperature detector 9, and is installed in the room 10.
The gas side (hereinafter, also referred to as a gas line) and the liquid side (hereinafter, also referred to as a liquid line) of the outdoor unit 6 and the indoor unit 7 are connected by a gas side pipeline 11 and a liquid side pipeline 12 to form a closed circuit. Is forming. The pressure detector 1 is installed in the gas side pipeline 11 of the outdoor unit 6.
3 is provided, and a known heat pump cycle in which a refrigerant is enclosed in a closed circuit is shown in the same figure.

An embodiment of the air conditioner having such a configuration will be described below.

The ordinary air conditioner shown in FIG.
And the indoor unit 7 as one set, the connection pipe lengths of the gas side pipeline 11 and the liquid side pipeline 12 that can be connected are defined. Here, during the heating operation, the indoor heat exchanger 8 acts as a condenser, and the liquid side conduit 12 between the indoor heat exchanger 8 and the expansion valve 4 arranged in the outdoor unit 6 is filled with the liquid refrigerant. During the cooling operation, the outdoor heat exchanger 3 acts as a condenser, and the liquid side conduit 12 between the expansion valve 4 arranged in the outdoor unit 6 and the indoor heat exchanger 8 is in a gas-liquid two-phase state. It is filled with a refrigerant (hereinafter, also simply referred to as a two-phase refrigerant), and the connection pipe length is specified so as to maintain an appropriate operating state in any of these cases.

During installation work of such an air conditioner,
When the connection pipe length is extended beyond the specified length, the amount of refrigerant corresponding to the liquid refrigerant during heating of the liquid side pipeline 12 and the two-phase refrigerant during cooling of the liquid side pipeline 12 is added depending on the length of the extended pipe. It is enclosed.

[0007]

However, as described above, in the case of an air conditioner having a so-called long pipe in which the length of the connecting pipe is longer than the specified length, it is necessary to additionally enclose the amount of refrigerant, which is troublesome in installation work. There was a problem that said it would cost.

Further, in such an air conditioner with long piping,
Since the rotation speed of the compressor 1 and the opening degree of the expansion valve 4 are set to be optimum for the specified connection pipe length, the added amount of enclosed refrigerant is not always optimum and the degree of superheat is excessive. Or, it becomes too small, the rotation speed of the compressor 1 becomes too small or too large, the output of the room temperature detector 9 does not match the room temperature set value, the problem that the power consumption of the compressor 1 becomes too large, and the refrigerant is in a liquid state. Therefore, there is a problem that the compressor 1 is damaged due to the liquid back phenomenon that is sucked into the compressor 1.

Further, such a conventional air conditioner uses HCFC22 as a refrigerant, but when HFC mixed refrigerant is used as an alternative refrigerant in the future, each component of the mixed refrigerant is accurately added and enclosed. It also has a problem that it is difficult to do.

In consideration of such problems of the conventional air conditioner, the present invention provides an assembling method of an air conditioner which does not require additional encapsulation of a refrigerant amount when a so-called long pipe connection is constructed. To aim.

Further, in consideration of such problems of the conventional air conditioner, the present invention does not require additional encapsulation of the amount of refrigerant when performing so-called long piping installation work, and is more suitable than the conventional one. The object is to provide an air conditioner that can perform various controls.

[0012]

According to a first aspect of the present invention, liquid lines are provided between an outdoor unit having at least a compressor, a four-way valve and an outdoor heat exchanger, and an indoor unit having at least an indoor heat exchanger. When connecting the gas lines to each other, if the length of the connecting member used to connect the liquid lines to each other is equal to or less than a predetermined length, the liquid lines are connected to each other by the pipe connection. Only by the members,
Further, when the length of the connecting member is equal to or longer than a predetermined length, a pipe connection between the liquid lines is performed by using a fixed throttle member together with the connecting member, and the refrigerant sealing amount is The method for assembling an air conditioner is substantially the same as the case where the length of the connecting member is less than or equal to the predetermined length.

According to a second aspect of the present invention, an expansion valve is arranged in the liquid line, and when the length of the connecting member is equal to or longer than a predetermined length, a connecting valve of the connecting member is used. It is a method of assembling an air conditioner, wherein the connecting member is arranged between the fixed throttle member and the expansion valve so that the state of the refrigerant inside is a gas-liquid two-phase state.

According to a third aspect of the present invention, an outdoor unit having at least a compressor, a four-way valve and an outdoor heat exchanger, an indoor unit having at least an indoor heat exchanger, and a liquid of the outdoor unit and the indoor unit. In order to connect the lines to each other, one end thereof is connected to the expansion valve side, and the liquid side conduit is connected to the other end of the liquid side conduit to connect the liquid lines. Attached piping having a fixed throttle member, a gas side conduit for connecting the gas lines of the outdoor unit and the indoor unit, a room temperature detector installed in the indoor unit, for detecting room temperature, the A compressor suction part, or an outdoor heat exchanger outlet or an indoor heat exchanger outlet acting as an evaporator, a superheat detector for detecting a superheat degree, and for matching the room temperature with a room temperature set value, the Room temperature controller that determines the manipulated variable of the opening of the expansion valve , A superheat controller for determining the manipulated variable of the opening degree of the expansion valve for matching the superheat degree with a superheat set value, and a membership value determined by a fuzzy calculation with the superheat degree as an input In order to match the room temperature with the expansion valve operation amount determiner that switches the operation amount by the superheat degree controller and the operation amount by the room temperature controller to determine the opening degree of the expansion valve and the room temperature. The operation amount of the compressor, the capacity controller that determines based on the room temperature, the room temperature set value and the rated capacity of the indoor unit, a pressure detector that detects the gas side pressure, and the pressure is set. A pressure controller for determining the operation amount of the rotation speed of the compressor to match the value, and the operation amount by the pressure controller and the operation amount according to the membership value determined by the fuzzy calculation using the pressure as an input. Operation by capacity controller Switching between quantity, an air conditioner having a compressor rotational speed determiner for determining the rotational speed of the compressor.

According to a fourth aspect of the present invention, when the expansion valve is arranged in an outdoor unit, an air conditioner in which an auxiliary pipe having the fixed throttle member is arranged in a liquid line inside the indoor unit. Is.

According to the present invention of claim 5, when the expansion valve is arranged in an indoor unit, an air conditioner in which an accessory pipe having the fixed throttle member is arranged in a liquid line inside the outdoor unit. Is.

According to a sixth aspect of the present invention, when the attached pipe having the fixed throttle member as a capillary tube is attached at the time of construction of long pipe connection, the entire attached pipe is covered with a protective pipe or a protective box. It is an air conditioner.

According to the present invention of claim 7, HF is used as the refrigerant.
It is an air conditioner using a C mixed refrigerant.

According to the present invention of claim 8, the outdoor unit is 1
The indoor unit connected to the outdoor unit is a plurality of units, and the expansion valve is provided corresponding to each of the indoor units, instead of the capacity controller, each of the above For each indoor unit, the operation amount of the compressor for matching each room temperature with each room temperature set value, each capacity to be determined based on each room temperature, each room temperature set value, and the rated capacity of each indoor unit The air conditioner includes a controller and an overall capacity controller that determines an operation amount of the compressor based on an output of each capacity controller.

The present invention has been made to solve the above problems. For example, when the connecting pipe length of the air conditioner is longer than the specified length, the outdoor unit and the indoor unit are The liquid lines are connected from the side where the expansion valve is arranged to the liquid side pipe line with the attached pipe with a fixed throttle member, and the gas lines are connected with the gas side pipe line and sealed regardless of the length of the extended pipe. The optimum operating state is maintained by adding the amount of refrigerant and controlling the expansion valve opening and compressor speed.

Further, in the present invention, for the problem that the degree of superheat becomes excessively large or too small, for example, the degree of superheat at the outlet of the outdoor heat exchanger or the outlet of the indoor heat exchanger acting as a compressor suction portion or an evaporator is A superheat detector that detects the superheat, a superheat controller that determines the manipulated variable of the opening of the expansion valve to match the superheat with the set value of the superheat, and a membership that is determined by fuzzy calculation using the superheat as an input. An expansion valve operation amount determiner that switches the operation amount by the superheat degree controller and the operation amount by the room temperature controller according to the value to determine the opening degree of the expansion valve is provided to keep the superheat degree within an appropriate range.

Further, in the present invention, the problem that the number of revolutions of the compressor is too small or too large with respect to the load of the room is
For example, a capacity controller that determines the compressor operation amount for matching the room temperature with the room temperature set value based on the room temperature, the room temperature set value, and the rated capacity of the indoor unit, and a pressure detector that detects the gas side pressure, The pressure controller for matching the pressure to the pressure set value, and the operation amount by the capacity controller and the operation amount by the pressure controller according to the membership value determined by fuzzy calculation with pressure as input. The compressor rotation speed determiner for determining the rotation speed of the compressor is provided by switching between the operation amount by the control unit and the operation amount by the capacity controller, and the rotation speed of the compressor is optimized while keeping the pressure within an appropriate range.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION An outline of the present invention will be given below before a detailed description of the embodiments of the present invention.

In the present invention, for example, when the length of the connecting pipe of the air conditioner according to one embodiment of the present invention is longer than the specified length, the outdoor unit and the indoor unit are arranged, and the expansion valves are arranged between the liquid lines. The liquid side conduit is connected to the liquid side conduit with an attached pipe having a fixed throttle member (for example, a capillary tube), and the gas lines are connected to each other by the gas side conduit so that the gas lines are arranged on the outdoor unit side, for example. Between the expansion valve and the fixed throttle member (capillary tube) attached to the indoor unit side, both during cooling and heating operation by switching the four-way valve,
It becomes a two-phase refrigerant state, and it is not necessary to offset the increase in the refrigerant amount due to the increase in the pipe length and to add the enclosed refrigerant amount.

What is required in the air conditioner with such a pipe connection is (1) when the length of the connection pipe is less than a specified length, that is, a fixed throttle member (capillary tube)
Control of expansion valve opening and compressor speed when not required, and (2) when the connection pipe length is longer than the specified length (in the case of long pipe connection), that is, fixed throttle member (capillary tube) ) Is attached to, for example, the indoor unit side, and the control of the expansion valve opening degree and the compressor rotation speed is integrated to maintain an optimal operating state in both cases (1) and (2) above. Is to establish a control method to do so.

Here, a superheat controller for determining the manipulated variable of the opening degree of the expansion valve for matching the superheat degree to the superheat set value, and the manipulated variable and the room temperature control by the superheat controller according to the superheat degree. With the expansion valve operation amount determiner that switches between the operation amount of the expansion device and the fixed throttle member (capillary tube), the superheat is fed back to control the opening of the expansion valve. Kept in. Also, a capacity controller that determines the operation amount of the compressor to match the room temperature with the room temperature set value, and a compressor rotation speed determiner that switches between the operation amount by the pressure controller and the operation amount by the capacity controller according to the pressure. The pressure is fed back to control the compressor speed regardless of the presence or absence of a fixed throttle member (capillary tube). The rotation speed is optimized, the output of the room temperature detector matches the room temperature set value, the power consumption of the compressor can be minimized, and the compressor can be prevented from being damaged by liquid back of the refrigerant. It is possible.

The auxiliary pipe having a fixed throttle member (capillary tube) is connected from the side where the expansion valve corresponding to the indoor unit to be connected is arranged via the liquid side pipe line, and the expansion valve is the outdoor unit. , The attached piping with the fixed throttle member (capillary tube) is placed in the liquid line inside the indoor unit, and when the expansion valve is placed in the indoor unit, the fixed throttle member (capillary tube) tube)
It goes without saying that the attached piping having the above may be arranged in the liquid line inside the outdoor unit. Further, in the case of a multi-room air conditioner in which one outdoor unit and a plurality of indoor units are connected via an expansion valve kit in which expansion valves corresponding to the plurality of connected indoor units are arranged, When the valve kit is installed near the outdoor unit, the attached piping with fixed throttle member (capillary tube) is placed in the liquid line near the indoor unit, and when the expansion valve kit is installed near the indoor unit. It is desirable to dispose an attached pipe having a fixed throttle member (capillary tube) in the liquid line near the outdoor unit in order to eliminate the need for additional charging of the amount of refrigerant.
Furthermore, when attaching an accessory pipe that uses a fixed throttle member as a capillary tube during the construction of a long pipe connection, it is desirable to cover the entire accessory pipe with a protective tube or protective box to prevent bending and damage of the capillary tube. . Further, it is desirable to change the specifications of the capillary tube according to the pipe length of the long pipe connection.

Further, the present air conditioner uses HC as a refrigerant.
FC22 is used, but HFC will be used as an alternative refrigerant in the future.
When using a mixed refrigerant, it is not necessary to accurately add each component of the mixed refrigerant, and when ester oil is used as the compressor lubricating oil, the system open time should be minimized to reduce the ester It has secondary effects such as preventing hydrolysis of oil.

(Embodiment 1) Hereinafter, one embodiment of an air conditioner according to the present invention at the time of long pipe connection will be specifically described with reference to the drawings.

FIG. 1 is a system configuration diagram of an air conditioner according to an embodiment of the present invention, which constitutes a heat pump cycle having the same operation as that of FIG. 8, and an outdoor unit in which an expansion valve 4 is arranged between liquid lines. From the 6 side, a liquid side conduit 12 is connected to a fixed throttle member by an accessory pipe 15 which is a capillary tube 14, gas lines are connected to each other by a gas side conduit 11, and further to a suction part of the compressor 1. The superheat detector 20 is attached, and the same elements as those in FIG. 8 are designated by the same reference numerals. In addition, FIG. 1 shows a case where the length of the liquid side conduit 12 used for connecting the liquid lines to each other in the method for assembling the air conditioner of the present invention is equal to or longer than a predetermined length. Further, when the length of the liquid side conduit 12 used for connecting the liquid lines to each other is equal to or shorter than a predetermined length, the liquid lines are connected to each other only by the liquid side conduit 12. It goes without saying that the lines are connected to each other by the gas side conduit 11. Further, the connecting member of the present invention corresponds to the liquid side conduit 12, and the fixed throttle member of the present invention corresponds to the capillary tube 14.

The operation of the air conditioner having such a configuration will be described below.

That is, during the heating operation, as shown by the solid line in FIG. 1, the refrigerant is compressed in the compressor 1 to become high-temperature and high-pressure vapor, passes through the four-way valve 2 and is discharged to the gas side pipeline 11. The indoor heat exchanger 8 in the indoor unit 7 is reached. At this time, the indoor heat exchanger 8 acts as a condenser, heats the air in the room 10 to heat the room 10, and the refrigerant is condensed and liquefied. The liquefied refrigerant reaches the outdoor heat exchanger 3 through the liquid side conduit 12 and the expansion valve 4. At this time, the outdoor heat exchanger 3
Acts as an evaporator, evaporates by receiving heat from the outside air, becomes low-pressure vapor, and is sucked into the compressor 1 through the four-way valve 2 and the accumulator 5. In the indoor unit 7 connected to the long pipe here, the refrigerant condensed and liquefied in the indoor heat exchanger 8 is temporarily depressurized by the capillary tube 14 of the attached pipe 15 and further depressurized by the expansion valve 4, so that the capillary tube 14 The liquid-side conduit 12 leading to the expansion valve 4 is filled with the two-phase refrigerant, and it is not necessary to add the amount of the enclosed refrigerant as compared with the case where there is no capillary tube.

Next, during the cooling operation, as shown by the broken line in FIG. 1, by switching the four-way valve 2, the outdoor heat exchanger 3 becomes a condenser,
The indoor heat exchanger 8 functions as an evaporator and absorbs heat from the air in the room 10 to cool the room 10. In the indoor unit 7 connected to the long pipe here, the refrigerant condensed and liquefied in the outdoor heat exchanger 3 is temporarily depressurized by the expansion valve 4 and further depressurized by the capillary tube 14 of the accessory pipe 15, so that the expansion valve 4 The liquid-side conduit 12 leading to the capillary tube 14 is filled with a two-phase refrigerant, and it is not necessary to add the amount of the enclosed refrigerant as compared with the case where there is no capillary tube.

Next, regarding the state of each part associated with the operation of the expansion valve 4, when the opening degree of the expansion valve 4 is increased, the flow rate of the refrigerant is increased, the room temperature of the room 10 is increased during the heating operation, and the cooling operation is performed. On the contrary, the temperature decreases, and the temperature is detected by the room temperature detector 9. Further, regarding the situation of each part associated with the operation of the compressor 1, as the number of rotations of the compressor 1 increases, the flow rate of the refrigerant increases, and the gas side pipeline 1 becomes a high pressure gas pipeline during heating operation.
1, the refrigerant pressure rises, and during the cooling operation, the refrigerant pressure in the gas side pipeline 11, which is the low-pressure gas pipeline, falls, and the pressure is detected by the pressure detector 13.

The operation of the air conditioner with such a configuration when connecting long pipes will be described below.

When the capillary tube 14 is attached near the indoor unit 7, if the opening of the expansion valve 4 is left as it is without the capillary tube, the circulation amount of the refrigerant flowing through the indoor heat exchanger 8 decreases. As a result, the degree of superheat in the superheat detector 20 becomes excessive, and the output of the room temperature detector 9 matches the room temperature set value, that is, at equilibrium,
The degree of superheat becomes too small or too large depending on the relationship with the load of the room 10, and the degree of superheat is detected by the superheat detector 20.

FIG. 2 is a block diagram of the controller of the expansion valve of the air conditioner according to the present invention.

As shown in the figure, the controller of the expansion valve of the air conditioner according to the present embodiment uses the outputs of the room temperature setting device 18 and the room temperature detector 9 as inputs to make the room temperature match the room temperature setting value. The controller 16, the superheat detector 20, and the superheat controller 22 that inputs the respective outputs of the superheat setter 21 that sets the target value of the superheat to match the superheat with the set value of the superheat, and the superheat detection An expansion for determining the opening of the expansion valve 4 by switching between the operation amount by the room temperature controller 16 and the operation amount by the superheat degree controller 22 according to the membership value determined by the fuzzy calculation using the output of the device 20 as an input. A valve opening determiner 23 is provided, and the opening of the expansion valve 4 is operated by the opening determined by the expansion valve opening determiner 23.

FIG. 3 is a block diagram of the controller of the compressor of the air conditioner according to the present invention.

As shown in the figure, the controller of the compressor of the air conditioner according to the present embodiment sets the indoor unit rated capacity value setter 24 for setting the rated capacity value of the indoor unit 7 and the target value of room temperature. The output of the room temperature setting device 18 and the room temperature detector 9 to be set are used as inputs, and the capacity controller 25 for determining the compressor operation amount for matching the room temperature to the room temperature target value, the pressure setting device 19, and the pressure detector 13 are set. Each of the outputs of the pressure detector 17 is used as an input, and a pressure controller 17 that determines a compressor operation amount for matching the pressure detected by the pressure detector 13 with a pressure set value, and a fuzzy operation using the output of the pressure detector 13 as an input. In accordance with the membership value determined in step 1, the operation amount by the capacity controller 25 and the pressure controller 17
And a compressor rotation speed determiner 27 for determining the rotation speed of the compressor 1 and operating the rotation speed of the compressor 1 with the operation quantity determined by the compressor rotation speed determiner 27. It is a thing.

The operation of the expansion valve and the controller of the compressor regardless of the presence or absence of the fixed throttle member (capillary tube) of the air conditioner in such a configuration will be described below.

That is, during the cooling operation, the room temperature detector 9
When the room temperature detected at is higher than the output of the room temperature setter 18, the room temperature controller 16 operates the valve opening of the expansion valve 4 in the opening direction, and the capacity controller 25 controls the rotation speed of the compressor 1. By operating in the increasing direction, as a result, the amount of refrigerant flowing through the indoor heat exchanger 8 that is decompressed by the capillary tube 14 and acts as an evaporator is increased, the cooling capacity is increased and the room temperature is decreased, and the output of the room temperature setting device 18 is matched. To do. This time,
When the required cooling capacity is larger than the capacity of the indoor heat exchanger 8, the expansion valve 4 opens too much and the superheat detected by the superheat detector 20 becomes small, so that the refrigerant is in a liquid state and the compressor 1 is in a liquid state.
If the superheat detected by the superheat detector 20 is smaller than the set minimum superheat threshold value, the expansion valve opening degree determiner 23
In step 3, the operation amount by the superheat degree controller 22 is selected, and the superheat degree detected by the superheat degree detector 20 is the superheat degree setter 21.
By operating the opening degree of the expansion valve 4 in the closing direction so as to match the output of, the cooling capacity of the indoor heat exchanger 8 is suppressed within the appropriate upper limit capacity. That is, the degree of superheat detected by the degree of superheat detector 20 becomes too small, and the compressor 1
It is possible to avoid the problem that the compressor 1 is damaged due to the liquid back phenomenon that is sucked in.

When the required cooling capacity is lower than the proper upper limit capacity of the indoor heat exchanger 8 due to the decrease in room temperature, the expansion valve opening degree determiner 23 is determined by the superheat detected by the superheat detector 20.
In the above, the operation amount by the superheat degree controller 22 and the operation amount by the room temperature controller 16 are appropriately switched, and the expansion valve 4 is opened so that the superheat degree is suppressed within the range of the maximum superheat degree threshold value and the minimum superheat degree threshold value. The degree is determined.

In addition, according to the pressure detected by the pressure detector 13, the compressor rotation speed determiner 27 causes the pressure controller 1
The amount of operation of the compressor 1 is appropriately switched between the amount of operation of the compressor 7 and the amount of operation of the capacity controller 25, and the rotation speed of the compressor 1 is determined so that the pressure is suppressed within the range between the maximum pressure threshold and the minimum pressure threshold.

As a result, the room temperature becomes lower than the output of the room temperature setting device 18, and the capacity controller 25 controls the rotation speed of the compressor 1 in a decreasing direction to allow the refrigerant flowing through the indoor heat exchanger 8 acting as an evaporator. The amount decreases, the cooling capacity decreases, and the room temperature rises, and the output of the room temperature detector 9 matches the output of the room temperature setting device 18.

Similarly, during the heating operation, when the room temperature detected by the room temperature detector 9 is lower than the output of the room temperature setting device 18, the room temperature controller 16 operates the valve opening of the expansion valve 4 in the opening direction. In addition, the capacity controller 25 operates the number of rotations of the compressor 1 in an increasing direction, and as a result, the amount of the refrigerant flowing through the indoor heat exchanger 8 which is reduced by the capillary tube 14 and acts as a condenser is increased, and the proper superheat degree is obtained. It is possible to realize room temperature control based on the pressure and pressure.

(Second Embodiment) Next, an embodiment of a multi-room air conditioner according to the present invention at the time of connecting long pipes will be described with reference to the drawings.

FIG. 4 is a system configuration diagram of a multi-room air conditioner according to the present invention, which constitutes a heat pump cycle having the same operation as in FIGS. 8 and 1, and the same elements as those in FIGS. 8 and 1 are the same. The numbers are given. The feature of the present embodiment is that one outdoor unit 6 and three indoor units 7A, 7
B and 7C are connected via the expansion valve kit 30 in which the expansion valves 4A, 4B and 4C corresponding to the three indoor units 7A, 7B and 7C to be connected are arranged, and in the present embodiment, expansion is performed. The valve kit 28 is installed in the vicinity of the outdoor unit 6, only the indoor unit 10C is connected to the long pipe, and the attached pipe 15 having the capillary tube 14 as the fixed throttle member is arranged in the liquid line in the vicinity of the indoor unit 7C.

The operation of the multi-room air conditioner having such a configuration will be described below. That is, during the heating operation, as shown by the solid line in FIG. 4, the refrigerant is compressed in the compressor 1 into high-temperature and high-pressure vapor, passes through the four-way valve 2, and the expansion valve kit 25
Through each of the gas side pipelines 11A, 11B, 11C, and each indoor heat exchanger 8 in each indoor unit 7A, 7B, 7C
A, 8B, 8C. At this time, each indoor heat exchanger 8
A, 8B and 8C act as condensers, and each room 10A, 1
Each room 10 by applying heat to 0B and 10C air
A, 10B and 10C are heated and the refrigerant is condensed and liquefied. The liquefied refrigerant reaches the outdoor heat exchanger 3 through the liquid-side conduits 12A, 12B, 12C and the expansion valves 4A, 4B, 4C in the expansion valve kit 30. At this time, the outdoor heat exchanger 3
Acts as an evaporator, evaporates by receiving heat from the outside air, becomes low-pressure vapor, and is sucked into the compressor 1 through the four-way valve 2 and the accumulator 5. Here, only in the indoor unit 7C that is connected to the long pipe, the refrigerant condensed and liquefied in the indoor heat exchanger 8C is once decompressed by the capillary tube 14 of the accessory pipe 15 and further decompressed by the expansion valve 4C, so that the capillary tube 14 Line 1 from the expansion valve to the expansion valve 4C
2C is filled with a two-phase refrigerant, and it is not necessary to add the amount of the enclosed refrigerant as compared with the case where there is no capillary tube.

Next, during the cooling operation, as shown by the broken line in FIG. 4, by switching the four-way valve 2, the outdoor heat exchanger 3 becomes a condenser,
Each indoor heat exchanger 8A, 8B, 8C acts as an evaporator,
The rooms 10A, 10B, 10C are cooled by absorbing heat from the air in the rooms 10A, 10B, 10C. Here, only in the indoor unit 7C connected by the long pipe, the refrigerant condensed and liquefied in the outdoor heat exchanger 3 is temporarily decompressed by the expansion valve 4C,
Since the pressure is further reduced by the capillary tube 14 of the attached pipe 15, the liquid side conduit 12C from the expansion valve 4C to the capillary tube 14 is filled with a two-phase refrigerant, and the amount of the enclosed refrigerant is smaller than that in the case without the capillary tube. No need to add.

Next, the operation mode of each expansion valve 4A, 4B, 4C is as follows when the opening degree of each expansion valve 4A, 4B, 4C is increased.
As the refrigerant flow rate increases, each room 10A, 1
The room temperature of 0B and 10C rises, and conversely decreases during the cooling operation, and the temperature is detected by the respective room temperature detectors 9A, 9B and 9C. In addition, the operation mode of the compressor 1 is such that when the rotation speed of the compressor 1 is increased, the flow rate of the refrigerant is increased, and each gas side pipeline 11A, 11B, 1 that becomes a high pressure gas pipeline during heating operation.
The refrigerant pressure in 1C rises, the refrigerant pressure in each gas side pipeline 11A, 11B, 11C which becomes a low pressure gas pipeline in cooling operation falls, and the pressure is detected by the pressure detector 13.

In such a multi-room air conditioner, control of each room temperature according to the load of each room 10A, 10B, 10C and maintenance of the reliability of the compressor or reduction of power consumption is performed. It is necessary to control the pressure and the degree of superheat for efficient operation.

The operation of the multi-room air conditioner having such a configuration at the time of connecting the long pipe will be described below.

When the capillary tube 14 is attached near the indoor unit 7C, if the expansion valves 4A, 4B, and 4C are left open without the capillary tube, the refrigerant circulation through the indoor heat exchanger 8C. The amount has decreased,
As a result, the superheat in the superheat detector 21 becomes excessive,
Further, in a state where the outputs of the room temperature detectors 9A, 9B and 9C match the room temperature set values, that is, at the equilibrium time, each room 10
Depending on the relationship with the load of A, 10B, and 10C, the degree of superheat becomes too small or too great.
Is detected.

FIG. 5 is a block diagram of the controller of each expansion valve of the multi-room air conditioner according to the present invention.

As shown in the figure, the controller of each expansion valve of the multi-room air conditioner of the present embodiment is provided with each room temperature setting device 18
Room temperature controllers 16A, 16B, 16C that match each room temperature with the target value of each room temperature by using the outputs of A, 18B, 18C and each room temperature detector 9A, 9B, 9C as input, and the superheat detector 20 and overheat Determining by a fuzzy operation with the output of the superheat detector 20 as the input and the superheat controller 22 that inputs the output of the superheat setter 21 that sets the target value of the superheat to match the superheat with the set value of the superheat Depending on the membership value
The operation amount by each room temperature controller 16A, 16B, 16C and the operation amount by the superheat degree controller 22 are switched, and each expansion valve 4 is operated.
Expansion valve opening determiner 2 for determining the opening of A, 4B, 4C
3A, 23B, 23C, and each expansion valve 4 at the opening determined by each expansion valve opening determiner 23A, 23B, 23C.
The opening degree of A, 4B, and 4C is operated.

FIG. 6 is a block diagram of the controller of the compressor of the multi-room air conditioner according to the present invention.

As shown in the figure, the controller of the compressor of the multi-room air conditioner according to the present embodiment includes the indoor units 7A, 7B,
Each indoor unit rated capacity value setter 24A, 24B, 24C for setting each rated capacity value of 7C, and each room temperature setter 18A, 18B, 18C for setting a target value of each room temperature and each room temperature detector 9
Each capacity controller 25A, 25B, 25C and each capacity controller 25 for determining the compressor operation amount for matching each room temperature with each room temperature target value by using each output of A, 9B, 9C as an input
The pressure detected by the pressure detector 13 is set as a pressure set value by using the overall capacity controller 26 that outputs the sum of the outputs of A, 25B, and 25C and the outputs of the pressure setter 19 and the pressure detector 13 as inputs. The operation amount and the pressure control by the overall capacity controller 26 according to the pressure controller 17 that determines the compressor operation amount for matching and the membership value that is determined by the fuzzy calculation using the output of the pressure detector 13 as input. And a compressor rotation speed determiner 27 that determines the rotation speed of the compressor 1 by switching the operation quantity by the compressor 17. The rotation speed of the compressor 1 is determined by the operation quantity determined by the compressor rotation speed determiner 27. It is something to operate.

The operation of each expansion valve and the controller of the compressor regardless of the presence or absence of the fixed throttle member (capillary tube) of the multi-room air conditioner in such a configuration is as shown in FIG. Similar to an air conditioner having a one-to-one correspondence with, room temperature control can be realized based on an appropriate degree of superheat and pressure during both heating and cooling operation.

(Third Embodiment) Here, the capillary tube 14 used for long pipe connection of the air conditioner or the multi-room air conditioner described in the above embodiment will be described more specifically. . FIG. 7 shows an embodiment of an accessory pipe 15 having a capillary tube 14 as a fixed throttle member of the present invention.

In FIG. 7, 14 is a capillary tube, and 29 is a capillary tube 1 for piping work.
4 is a protective pipe for preventing bending and breakage, and 30 is a pipe joint for connecting the liquid side pipeline 12 from the outdoor unit 6 and the indoor unit 7.

Here, the protective tube 29 can prevent bending of the capillary tube 14 if it is made of, for example, a pipe-shaped one, but in addition to that, for example, a protective tube made of a wire in a spiral shape (that is, in a spring-spring shape). In this case, it is more desirable because the capillary tube 14 can be prevented from being bent and bending can be performed to some extent according to the piping construction site.

The pipe joint 30 may be brazed and welded, but if it is a flare connection or a packing is used, the man-hours for brazing and welding can be reduced and an oxide film is formed in the pipe. When ester oil is used as the compressor lubricating oil, it is more desirable from the viewpoint of reliability that the system opening time is minimized to prevent hydrolysis of the ester oil.

The pressure detector for detecting the gas-side pressure described in the above embodiment calculates the refrigerant saturation temperature or uses the maximum pressure threshold and the minimum pressure in order to use it as an input to the superheat detector. This is to detect the pressure directly in order to protect the compressor within the proper range of the pressure threshold.The point is that if the refrigerant saturation temperature on the user side is known, the pressure can be calculated in reverse. Is. Therefore, the pressure detector of the present invention can be replaced by the refrigerant saturation temperature detector.

Further, although the fixed throttle member for connecting the long pipe described in the above-mentioned embodiment is constituted by the capillary tube, the present invention is not limited to this, and the fixed throttle member does not depend on other control algorithms, for example. It goes without saying that valves with a throttle mechanism can be used instead.

Further, in the above-mentioned embodiment, the case where the fixed throttle member is used when the long pipe is connected and the control of the expansion valve opening degree and the compressor rotation speed and the like is performed more finely than the conventional one has been described. Not limited to this, for example, a fixed throttle member may be used at the time of long pipe connection, and the control method may be the same as the conventional one, and the content of the control does not matter.

As described above, in the air conditioner according to the present invention, for example, the outdoor unit and the indoor unit are arranged, and the liquid lines are connected from the side where the expansion valve is arranged to the liquid side pipe line and the fixed throttle member (capillary tube). ) With the attached piping,
The gas lines are connected to each other by a gas side pipe to seal the refrigerant,
In addition to the room temperature controller that controls the room temperature, the superheat detector that detects the superheat at the compressor intake or the evaporator outlet, and the expansion valve that matches the superheat to the superheat setting value A fixed throttle member (capillary tube) is provided by a superheat controller that determines the operation amount of the opening and an expansion valve opening determiner that switches between the operation amount by the superheat controller and the operation amount by the room temperature controller according to the degree of superheat. With or without), the superheat is fed back to control the opening of the expansion valve and the capacity controller that determines the rotation speed of the compressor to match the room temperature with the room temperature set value, and the pressure depending on the pressure. The compressor rotation speed determiner, which switches between the operation amount by the controller and the operation amount by the capacity controller, feeds back the pressure regardless of the presence or absence of the fixed throttle member (capillary tube) to determine the rotation speed of the compressor. Therefore, this does not depend on the pipe length of the long pipe connection, does not require the addition of the enclosed refrigerant amount, and always realizes room temperature control based on an appropriate degree of superheat and pressure, and reduces the power consumption of the compressor. It can be minimized, and damage to the compressor due to the liquid back of the refrigerant can be prevented.

Further, for example, by covering the entire attached pipe using the fixed throttle member as a capillary tube with a protective pipe or a protective box, it is possible to prevent the capillary tube from being bent or damaged during the piping work.
When using an HFC mixed refrigerant as an alternative refrigerant, it is not necessary to accurately add each component of the mixed refrigerant accurately, and when using ester oil as the compressor lubricating oil, the system open time is minimized. Then, it brings about a secondary effect such as prevention of hydrolysis of the ester oil.

[0069]

As is apparent from the above description, the present invention has an advantage that it is not necessary to additionally fill the amount of the refrigerant when the so-called long pipe connection is constructed.

In addition to the above advantages, the present invention has an advantage that more appropriate control can be performed as compared with the conventional case when performing so-called long piping installation work.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an air conditioner according to an embodiment of the present invention.

FIG. 2 is a control block configuration diagram of an expansion valve of an air conditioner according to an embodiment of the present invention.

FIG. 3 is a control block configuration diagram of a compressor of an air conditioner according to an embodiment of the present invention.

FIG. 4 is a system configuration diagram of a multi-room air conditioner according to an embodiment of the present invention.

FIG. 5 is a control block configuration diagram of an expansion valve of a multi-room air conditioner according to an embodiment of the present invention.

FIG. 6 is a control block configuration diagram of a compressor of a multi-room air conditioner according to an embodiment of the present invention.

FIG. 7 is a configuration diagram of attached piping in which the fixed throttle member of the air conditioner of the embodiment according to the present invention is a capillary tube.

FIG. 8 is a system configuration diagram of a conventional air conditioner.

[Explanation of symbols]

 1 compressor 2 4-way valve 3 outdoor heat exchanger 4 expansion valve 5 accumulator 6 outdoor unit 7 indoor unit 8 indoor heat exchanger 9 room temperature detector 10 room 11 gas side pipe 12 liquid side pipe 13 pressure detector 14 fixed throttle Member (capillary tube) 15 Attached piping 16 Room temperature controller 17 Pressure controller 18 Room temperature setter 19 Pressure setter 20 Superheat detector 21 Superheat setter 22 Superheat controller 23 Expansion valve opening determiner 24 Indoor unit rating Capacity value setter 25 Capacity controller 26 Overall capacity controller 27 Compressor rotation speed determiner 28 Expansion valve kit 29 Protective pipe 30 Piping joint

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masataka Ozeki 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor, Mitsuharu Matsuo 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] 1. A liquid line between an outdoor unit having at least a compressor, a four-way valve, and an outdoor heat exchanger, and an indoor unit having at least an indoor heat exchanger. When the length of the connecting member used for connecting the lines to each other is equal to or less than a predetermined length, the liquid lines are connected to each other only by the connecting member, and the length of the connecting member is However, when the length is equal to or longer than a predetermined length, the liquid lines are connected to each other by using the fixed throttle member together with the connection member, and the amount of the refrigerant filled is determined by the predetermined length of the connection member. A method for assembling an air conditioner, which is characterized in that it is substantially unchanged as compared with the case of a length or less. 2. An expansion valve is arranged in the liquid line, and when the length of the connecting member is equal to or longer than a predetermined length, the state of the refrigerant inside the connecting member is The method for assembling an air conditioner according to claim 1, wherein the connecting member is arranged between the fixed throttle member and the expansion valve so as to be in a gas-liquid two-phase state. 3. An outdoor unit having at least a compressor, a four-way valve, and an outdoor heat exchanger, an indoor unit having at least an indoor heat exchanger, and for connecting liquid lines between the outdoor unit and the indoor unit. And a liquid side conduit whose one end is connected to the expansion valve side, and an accessory pipe having a fixed throttle member connected to the other end of the liquid side conduit for connecting the liquid lines to each other. A gas side conduit for connecting the gas lines between the outdoor unit and the indoor unit, a room temperature detector installed in the indoor unit for detecting room temperature, the compressor suction unit, or, At the outlet of the outdoor heat exchanger or the outlet of the indoor heat exchanger that acts as an evaporator, and a superheat detector that detects the degree of superheat, and the operation of the opening degree of the expansion valve to match the room temperature with a room temperature set value. A room temperature controller that determines the amount of Degree superheat degree controller for determining the manipulated variable of the opening degree of the expansion valve in order to match the degree set value, and the superheat degree control according to the membership value determined by the fuzzy calculation using the degree of superheat as an input. Valve operation amount determiner for determining the opening degree of the expansion valve by switching between the operation amount of the expansion chamber and the operation amount of the room temperature controller, and the operation of the compressor for matching the room temperature with the room temperature set value. A capacity controller that determines the amount based on the room temperature, the room temperature set value, and the rated capacity of the indoor unit; a pressure detector that detects the gas side pressure; and a pressure controller that matches the pressure with the pressure set value. A pressure controller that determines the operation amount of the rotation speed of the compressor, and an operation amount by the pressure controller and an operation amount by the capacity controller according to a membership value determined by a fuzzy calculation using the pressure as an input. Switch between and An air conditioner characterized by comprising a compressor rotational speed determiner for determining the rotational speed of the compressor. 4. When the expansion valve is arranged in an outdoor unit, an auxiliary pipe having the fixed throttle member is arranged in a liquid line inside the indoor unit.
The air conditioner as described. 5. When the expansion valve is arranged in an indoor unit, an accessory pipe having the fixed throttle member is arranged in a liquid line inside the outdoor unit.
The air conditioner as described. 6. The auxiliary pipe, wherein the fixed throttle member is a capillary tube, is attached to the pipe during construction of long pipe connection, and the entire auxiliary pipe is covered with a protective pipe or a protective box. Item 3. The air conditioner according to Item 3. 7. The air conditioner according to claim 3, wherein an HFC mixed refrigerant is used as the refrigerant. 8. The outdoor unit is one, the indoor unit connected to the outdoor unit is a plurality, and the expansion valve is provided corresponding to each of the indoor units, Instead of the capacity controller, for each of the indoor units, the operation amount of the compressor to match each room temperature to each room temperature set value, the room temperature, the room temperature set value and the indoor unit of each 4. A capacity controller which is determined based on a rated capacity, and an overall capacity controller which determines an operation amount of the compressor based on an output of each capacity controller. Air conditioner.