JPH0282047A - Air conditioning device for multiroom type housing - Google Patents

Abstract

PURPOSE:To improve the efficiency of heat exchange by a method wherein based on the operation mode of an indoor device, first and second switching means are controlled to a cooling or a heating mode, and according to a difference between a refrigerant temperature detected by an outdoor device refrigerant temperature detecting part and a set value for a condenser of the temperature or the set value for a vaporizer thereof, an airflow of a blower and a refrigerant flow rate are controlled. CONSTITUTION:A title air conditioning device comprises one outdoor unit Uout provided with a compressor 1 and an outdoor heat exchanger 2 and a plurality of indoor units UIN 1-UIN4, each having indoor heat exchangers HE1-HE4 to form refrigerant routes arranged in parallel to each other having the one end connected to the one end of the outdoor unit Uout, and performs cooling and heating of multirooms. In this case, based on an operation mode detected by an indoor device operation detecting part 9, a heat exchange control part 8 controls first switching valves SV1 and SV2 and second switching valves SV5-SV12 to a cooling mode or a heating mode, and controls an airflow regulating device 4 of a blower 3 and refrigerant flow rate control valves SV3 and SV4 according to a difference between a refrigerant temperature Tout detected by a refrigerant temperature set part Dout of the outdoor heat exchanger 2, and a set value Th1 for a condenser of the refrigerant temperature of the outdoor device heat exchanger 2 or a set value Th2 for a vaporizer.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention comprises one outdoor unit equipped with a compressor and a heat exchanger, and a plurality of indoor units each equipped with an indoor heat exchanger. The present invention relates to a heat pump type air conditioner for multi-room residential buildings.

(Prior Art) This type of air conditioner for residential buildings performs cooling and heating by switching the path of refrigerant compressed by a compressor using, for example, a four-way valve. In other words, compressed refrigerant is expanded via an outdoor heat exchanger and circulated to an indoor heat exchanger for cooling, or compressed refrigerant is expanded via an indoor heat exchanger and then circulated to an indoor heat exchanger for cooling. Heating is performed by circulation through a heat exchanger.

(Problem to be Solved by the Invention) However, in the above-mentioned heat pump type air conditioner for residential buildings, a multi-room air conditioner capable of simultaneous cooling and heating operation is similar to the device shown in Japanese Patent Application Laid-open No. 12372/1983. In addition, the load range is wide from cooling load to heating load, and especially in outdoor units that handle multiple indoor units, the load changes depending on whether each indoor unit is operating or not. proper refrigerant flow conditions are not achieved, thus reducing system efficiency. In other words, in the case of operation where there is a considerable difference between the cooling load and the heating load because an appropriate capacity control system has not been established in the above-mentioned equipment, the heat balance becomes unbalanced and pressure fluctuations in the refrigerant circuit occur. This caused the problem that stable operation could not be maintained, resulting in a decrease in the coefficient of performance.

The first object of the present invention is to enable each indoor unit to be used in combination with each other for cooling and heating, and to provide multiple rooms with good system efficiency when the heating and cooling load fluctuates or when heating and cooling are used simultaneously. The purpose is to provide an air conditioner for a residential building, and the second purpose is to provide a multi-room type air conditioner that quickly stabilizes the function after switching the outdoor heat exchanger from a condenser to an evaporator. Our objective is to provide air conditioning equipment for residential buildings.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the invention according to claim (1) provides a single outdoor unit including a compressor and an outdoor heat exchanger, and a compressor and an outdoor heat exchanger. A multi-room residential building that cools and heats multiple rooms, consisting of a plurality of indoor units each equipped with an indoor heat exchanger and forming parallel refrigerant paths, one end of each of which is connected to one end of an outdoor unit. In the air conditioner, the outdoor heat exchanger has a refrigerant path divided into a plurality of parts, and a first switching means for switching the refrigerant path on the other end side of the outdoor heat exchanger to a high pressure side or a low pressure side of the compressor; , a second switching means for switching each other end of the indoor unit to the high-pressure side or the low-pressure side of the compressor, an air volume adjusting device for adjusting the air volume of a heat exchange blower of the outdoor heat exchanger, and an outdoor heat exchanger. a refrigerant flow control valve that individually controls the refrigerant flow rate of each of the divided paths; an indoor unit operation detection unit that detects each operation designation of cooling and heating of each indoor unit and its operation mode; and an outdoor heat exchanger. controlling the first and second switching means to a cooling mode or a heating mode based on the operation mode detected by the outdoor unit refrigerant temperature detection section that detects the refrigerant temperature of the device and the indoor unit operation detection section; a heat exchange control unit that controls the air volume adjustment device and the refrigerant flow rate control valve according to a difference between the refrigerant temperature detected by the outdoor unit refrigerant temperature detection unit and a set value for the condenser or a set value for the evaporator of the refrigerant temperature; Equipped with.

In the invention of claim (2), the first switching means includes a first on-off valve that opens and closes the refrigerant path between the high-pressure side of the compressor and the other end side of the outdoor heat exchanger; a second on-off valve that closes a refrigerant path between the low-pressure side of the machine and the other end of the outdoor heat exchanger when at least the first on-off valve is open and opens or closes when the first on-off valve is closed; The heat exchange control section further includes a refrigerant pressure reduction path formed of a pressure reduction mechanism and connected in parallel to the second on-off valve, and the heat exchange control section further controls the refrigerant temperature detected by the outdoor unit temperature detection section with respect to the first switching means. is higher than a predetermined evaporator transfer setting value, the second on-off valve is controlled to close in preference to other conditions.

(Function) According to the present invention, the first switching means connects the other end of the outdoor heat exchanger to the high pressure side of the compressor, and the second switching means connects the other end of the indoor unit to the low pressure side of the compressor. When the other end of the outdoor heat exchanger is connected to the low pressure side of the compressor, heating is performed when the other end of the indoor unit is switched to the high pressure side of the compressor. In the former connection state by the switching means, when the second switching means switches and connects the other ends of some indoor units to the low pressure side of the compressor, and switches and connects the other ends of other indoor units to the high pressure side of the compressor. Cooling using the outdoor unit and the partial indoor unit as a refrigerant path, and heating using the refrigerant path using the other indoor unit as the high-pressure side and the partial indoor unit as the low-pressure side are performed simultaneously. When the load on the outdoor unit changes due to simultaneous use of cooling and heating, or due to some indoor units being idle, the air volume adjustment device operates to adjust the air volume of the heat exchange blower, and also adjust the air flow rate of each outdoor heat exchanger. The flow rate of each divided refrigerant path is controlled by the operation of the control valve.

When the first on-off valve is switched from open to closed, the refrigerant temperature in the outdoor heat exchanger rises, but according to the invention of claim (2), at this time, the second on-off valve is temporarily switched off. By keeping it closed, the refrigerant is cooled via the pressure reducing mechanism and the refrigerant temperature drops.

(Embodiment) FIG. 1 is a system diagram of an air conditioner for a multi-room residential building showing an embodiment of the present invention.

In the figure, U out is an outdoor unit, 1 is a compressor (C), 2 is an outdoor heat exchanger, 3 is a heat exchange blower for the outdoor heat exchanger 2, and 4 is an air volume adjustment that adjusts the rotation speed of the blower 3. The device 5 is an accumulator. SVl is a first on-off valve made of a solenoid valve, which opens and closes the refrigerant path between the high-pressure side of the compressor 1 and the outdoor heat exchanger 2. SV2 is a second on-off valve made of a solenoid valve, which closes the refrigerant path between the low pressure side of the compressor 1 and the outdoor heat exchanger 2 when the on-off valve Sv1 is open, and opens or closes when it closes. do. The first and second on-off valves described above constitute a first switching means.

6 is a capillary as a pressure reducing mechanism, which is connected in parallel with the on-off valve SV2, and when each on-off valve SVI is open and SV2 is closed, when SVI is closed and SV2 is open,
A refrigerant pressure reduction path is temporarily formed by the control described later.

The outdoor heat exchanger 2 has each heat exchange path 2A divided into two systems.
, 2B, an expansion valve EVA and a check valve CVA are connected to the two heat exchange paths, and an expansion valve E is connected to the heat exchange path 2B.
VB and check valve CVB are connected.

SV3. SV4 is a refrigerant flow control valve consisting of a solenoid valve that individually controls the refrigerant flow rate of the two heat exchange paths or 2B. A pressure sensor 7 detects the low-pressure side inlet pressure Ps of the compressor 1, and its value is used for on/off control of the compressor 1, which will be described later. D out is an outdoor unit refrigerant temperature detection unit that detects the refrigerant temperature T out of the outdoor heat exchanger 2, and Dao is an outdoor unit outdoor air temperature detection unit that detects the outdoor air temperature Tao of the outdoor heat exchanger 2.

UINL to UIN4 are indoor units used for cooling or heating each room, HEI to HE4 are their respective indoor heat exchangers, RTI-RT4 is a receiver tank, and EVI-E
V4 is an expansion valve, and CV1 to CV4 are check valves. Each of the indoor units UINI to UIN4 forms a parallel refrigerant path, and one end of each of the refrigerant paths is commonly connected to the outdoor heat exchanger 2 . SV5 to SV8 are switching valves formed of solenoid valves, which individually open or close the refrigerant paths between the other ends of the indoor heat exchangers HEI to HE4 and the low pressure side of the compressor 1. SV9 to 5V12 are solenoid valves that operate in opposite directions to the pair of switching valves SV5 to Sv8. Individually open or close the refrigerant path between the high pressure side and the high pressure side. Each of the switching valves SV5 to 5V12 described above constitutes second switching means.

D1 to D4 are indoor temperature detection units that detect the indoor unit inlet temperatures Tal of the indoor units UINI to UIN4, respectively.

8 is a heat exchange control section, and FIG. 2 is a block diagram showing its details. 9 is an indoor unit operation detection section, and each indoor unit U
In response to each operation signal from the operation switches INI to UIN4 (not shown), each operation designation of cooling and heating and its operation mode are detected.

The heat exchange control unit 8 receives a detection signal from the indoor unit operation detection unit 9,
Each temperature detection unit Dout through the A/D converter A/D,
Dao, Di to D4 and the value of the pressure sensor 7 are input to the input circuit DWIN. The output circuit DVout controls the opening and closing of the six valves SV1 to 5V12, as well as controls the motor rotation for the air volume adjustment device 4 of the blower 3, on/off control of the compressor 1, and controls the indoor heat exchanger HEI-
Motors M1 to M of each blower (not shown) in HE4
4 rotation control. Each of these controls is carried out by the central processing unit C.
This is performed by the PU using a program to be described later. M
is a memory for storing these programs.

Next, the operation of the air conditioner for a multi-room residential building shown in FIG. 1 will be explained.

FIG. 3 is a flowchart showing the operation of the air conditioner shown in FIG.

When the indoor units U INI - U IN4 are designated to operate (St), a first set value Thl and a second set value Tn2 for controlling the outdoor unit are calculated for the control described later (S2).

FIG. 4 is an explanatory diagram of the calculation of the respective stage constant values Thl and Th2. The first set value Thl is set for each indoor unit UINI-
This is the set value for the refrigerant temperature Tout by the outdoor unit refrigerant temperature detection unit D out when UIN4 is specified for cooling or cooling and heating and the outdoor heat exchanger 2 is operating as a condenser. The temperature is set to be a value higher than the outdoor unit outside air temperature Tao detected by the temperature detection section Dao by a predetermined value α.

An allowable control range ΔT1 is set for the set value Thl.

Similarly, the second set value Th2 is a set value for the refrigerant temperature T out when the outdoor heat exchanger 2 is operating as an evaporator in heating specification, and is the set value for the outdoor unit outside air temperature Ta.
The value is set to be a predetermined value β lower than o.

An allowable control range ΔT2 is set for the set value Th2.

The number of heating settings Hn is the total number of indoor units (total number of units N-
4), (S3), 6-valve SV2. SV3
．． Turn on (open) SV4, turn off (close) valve SVI, and set outdoor heat exchanger 2 to heating mode as an evaporator (S
4). When the specified number of cooling units Cn is equal to the total number of units N (S5), turn on the six valves SVI, SV3, and SV4;
The valve SV2 is turned off and the outdoor heat exchanger 2 is set to cooling mode as a condenser (S6). Also, when the number of designated heating Hn is 3 or less and the designated number of cooling Cn is 1 to 3 (S3°S5.
S7), 6 valves SVI, SV3 are turned on, each valve SV2. S.V.
4 is turned off, and one heat exchange path 2 of the outdoor heat exchanger 2 is turned off.
The air conditioner is operated as a human-operated condenser (S8). Also,
When the designated cooling number Cn is 0 and the designated heating number Hn is 3 or less (S3.S7), the road valve SV2. Turn on SV3, road valve SVI
, SV4 is turned off and one heat exchange path of the outdoor heat exchanger 2 is set to heating mode as an evaporator for two people (S9).
. If the operation designation of each of the indoor units UINI to UIN4 is cooling designation (S10), the road valve SV5
-Turn on the valve corresponding to each indoor unit designated for cooling among the air conditioners in SV8, and turn off the valve corresponding to each indoor unit designated for cooling among road valves SV9 to 5V12 (S
11). For the control described later, a set value p5set of the pressure Ps of the pressure sensor 7 is set to the outdoor heat exchanger 2.
The pressure setting value p5sett is set when is the condenser (S12). Also, if heating is specified (S10)
, turn off the valve corresponding to each indoor unit designated for heating among road valves SV5 to SV8, and turn on the valve corresponding to each indoor unit designated for heating among road valves SV9 to 5V12 (313). . Similarly, the set value p of the pressure Ps
5set, the pressure setting value P5set2 is set when the outdoor heat exchanger 2 is an evaporator (S14). Note that each of the above-mentioned set values P5set has its respective upper tolerance range ΔPs set therein.

Next, the air temperature specified value T alset at the inlet of the indoor heat exchangers HEI to HE4 and the indoor unit inlet temperature Ta1 determined by each indoor temperature detection unit Di to D4 (
The output setting value P f of the blower 3 is determined from the six values for one unit (when I to HE4 are in operation) and the predetermined constants a and b.
'set as the formula, P f'set -aT al -T
Calculate by alset l + b (S 1
5).

FIG. 5 is an explanatory diagram of the calculation of the output setting value P f'set of the blower 3 in the cooling mode and the heating mode.

In the figure, the cooling mode is shown on the right side, and the heating mode is shown on the left side. The constant a indicates the slope of the output set value P fset, and the constant a indicates the minimum value of the output set value P fset.

Next, compressor 1, blower 3, and each indoor unit U IN
I-U IN4 blower (not shown) motor Ml-
Turn on M4 (S 1B).

When the refrigerant path is controlled in steps S4 or S9 and S13, the refrigerant compressed by the compressor 1 passes through the valves SV9 to 5V12 and then to the indoor heat exchangers HEI to HE.
4, etc., for heating, expands and absorbs heat in the outdoor heat exchanger 2, and returns to the compressor 1 via the valve SV2, etc. Also,
When the refrigerant path is controlled by step S6 or S8 and Sit, the refrigerant compressed by the compressor 1 passes through the valve SVl, etc., and releases heat in the outdoor heat exchanger 2, and then the heat is released in the indoor heat exchangers HEI to HE4. It is cooled by absorbing heat, and valve SV5~
It returns to compressor 1 via SV8. Also, step S6 or S
If the refrigerant path is controlled by 8, Sll, and S13,
For example, valves SV5, 5VIO are on, SV8. If SV9 is off, the refrigerant compressed by compressor 1 will flow through valve sv
i, a route passing through outdoor heat exchanger 2, indoor heat exchanger HE1, valve SV5, and valve 5VIO1 indoor heat exchanger HE2, HE
I, a path passing through valve SV5 is formed, cooling is performed by indoor heat exchanger HEI, and heating is performed by indoor heat exchanger HE2.

In this case, the refrigerant passing through the indoor heat exchanger HE2 is not released outdoors, but is heat exchanged for heating indoors and then used for cooling by the indoor heat exchanger HEI.

Next, if Hn>1 and Cn -0 is not specified,
That is, if a refrigerant path is formed by each step S6 or S8 and Sll (S17), the outdoor heat exchanger 2 is a condenser, and if Tout>Thl at this time (S1
8>, the rotation of the blower 3 is increased to sequentially increase its output Ps (S19), and as a result, P r > P f'se
t+7) (S20), the valve SV4 is turned on and the outdoor heat exchanger 2 uses each heat exchange path 2A, 2B (S2
1) Repeat the operations of each step 518 to S21. Further, if Pf>Pf'set is not established in step 520, the valve SV4 remains in the previous state and each step 818 to
Repeat the operation in S20. In step 8.1111, if Tout<Told-ΔTl instead of Tout>Thl (S22), the output Pf' is sequentially decreased (S23)
, if Pf < Pfset, valve SV4 is turned off (525), or if Pf < Pfset, valve SV4 is turned off.
The operations of steps 322 to 825 are repeated while keeping the previous state. In each of the above steps 818°S22,
If Thl>Tout>Th1-ΔT1 and the output Ps of the compressor 1 is Ps<Psset (S2B),
Turn off compressor 1 (S27). Based on the results, etc., if pS>Psset+ΔPs (S2B), turn on compressor 1 (529);
5set+ΔpB>PS>P If 5set (S2B, 528), the process returns to step S1.

In the above step S17, if Hn>1, Cn -0, that is, if a refrigerant path is formed in each step S4 or S9 and S13 (S30), the outdoor heat exchanger 2 is an evaporator, and the outdoor heat exchanger 2 is an evaporator. If T out is higher than the set temperature Th3 for evaporator transfer as the upper limit temperature when transferring the outdoor heat exchanger 2 to the evaporator (S30), the valve SV2 is turned off and the capillary 6 is temporarily switched off. Let the refrigerant pass through to reduce the pressure inside the outdoor heat exchanger 2 (S31), and if Tout>Th3 is no longer the case, turn off the valve SV2 (S32), and if Tout>Th2 (533)
, the output Pf is sequentially decreased (S34), and as a result, Pf'
When <Pfset (S35), the valve SV4 is turned off (836), and the operations of each step 333 to 83B are repeated. If Pr is not Pfset (S35), the operations of steps 333 to S35 are repeated with the valve SV4 in its previous state.

In step S33, Tout>Th2 and To
If ut<Th2-△T2 (S37), the output PI' is increased sequentially (S38), and when Pr>Pfset, turn on the valve SV4 (539), or pf>Pfse.
If it is not t, leave the valve SV4 in the previous state and proceed to each step 3.
Repeat operations 37-840, etc. Each of the above steps S33. In S37, Th2
>Tout>Th2-ΔT2, step S
Shift to 2B operation.

(Effects of the Invention) As explained above, according to the present invention, by combining the controls of the first and second switching means, it is possible to use a combination of cooling and heating, and in that case, the indoor units can be mutually controlled. Since heat is released and absorbed between the two, energy is saved. Then, the refrigerant path of the outdoor heat exchanger is divided into multiple parts, and the air volume of the heat exchange blower of the outdoor heat exchanger is adjusted depending on the usage status of the indoor unit and the refrigerant temperature of the outdoor heat exchanger.
Since a part of the refrigerant path is switched to use or non-use, heat exchange in the outdoor heat exchanger can be performed efficiently. Furthermore, when the outdoor heat exchanger is used as an evaporator, the refrigerant decompression path can be used at the beginning, so that the transition from the condenser to the evaporator can be made smoothly and quickly.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of a multi-room air conditioner showing an embodiment of the present invention, FIG. 2 is a block diagram of a heat exchange control section, FIG. 3 is a flow chart showing the operation of the air conditioner shown in FIG. 1, and FIG. The figure is the first
and each second set value T hl. An explanatory diagram of the calculation of Th2, FIG. 5 is an explanatory diagram of the calculation of the output setting value of the blower 3 in the cooling mode and the heating mode. DESCRIPTION OF SYMBOLS 1...Compressor, 2...Outdoor heat exchanger, 3...Blower for heat exchange, 4...Air volume adjusting device, 6...Capillary, 7...Pressure sensor, 8... Heat exchange control section, 9.
...Indoor unit operation detection section, T out...Outdoor unit refrigerant temperature, U! Nl -U IN4...Indoor unit, HEI~HE4...Indoor heat exchanger, D out
...Outdoor unit refrigerant temperature detection section, Vsl...first on-off valve, Vs2...second on-off valve, SV3,5V4-, flow control valve, S V5 to S V12-, second switching means.

Claims (2)

[Claims] (1) One outdoor unit equipped with a compressor and an outdoor heat exchanger, each equipped with an indoor heat exchanger, forming parallel refrigerant paths, each end of which is connected to one end of the outdoor unit. In a multi-room residential air conditioner that is composed of multiple indoor units and cools and heats multiple rooms, the outdoor heat exchanger forms a refrigerant path divided into multiple sections, and the other end of the outdoor heat exchanger a first switching means for switching the refrigerant path of the indoor unit to the high pressure side or the low pressure side of the compressor; a second switching means for switching each other end of the indoor unit to the high pressure side or the low pressure side of the compressor; An air volume adjustment device that adjusts the air volume of the heat exchange blower of the heat exchanger, a refrigerant flow control valve that individually controls the refrigerant flow rate of each of the divided paths of the outdoor heat exchanger, and cooling and heating of each indoor unit. an indoor unit operation detection section that detects each operation designation and its operation mode; an outdoor unit refrigerant temperature detection section that detects the refrigerant temperature of the outdoor heat exchanger; and an operation mode detected by the indoor unit operation detection section. Based on the above, the first and second switching means are controlled to a cooling mode or a heating mode, and the refrigerant temperature detected by the outdoor unit refrigerant temperature detection section and a set value for the condenser or a set value for the evaporator of the refrigerant temperature are controlled. An air conditioner for a multi-room residential building, comprising: a heat exchange control section that controls the air volume adjustment device and the refrigerant flow rate control valve according to the difference between the air flow rate control valve and the refrigerant flow rate control valve. (2) One outdoor unit equipped with a compressor and an outdoor heat exchanger, each equipped with an indoor heat exchanger, forming parallel refrigerant paths, one end of each of which is connected to one end of the outdoor unit. In a multi-room residential air conditioner that consists of multiple indoor units and cools and heats multiple rooms, the outdoor heat exchanger connects the refrigerant path divided into multiple sections to the other end of the outdoor heat exchanger. a first switching means for switching the refrigerant path to the high pressure side or the low pressure side of the compressor; a second switching means for switching each other end of the indoor unit to the high pressure side or the low pressure side of the compressor; an air volume adjustment device that adjusts the air volume of a heat exchange blower of the exchanger; a refrigerant flow control valve that individually controls the refrigerant flow rate of each of the divided paths of the outdoor heat exchanger; and the first switching means, A first on-off valve that opens and closes a refrigerant path between the high pressure side of the compressor and the other end of the outdoor heat exchanger, and a refrigerant path between the low pressure side of the compressor and the other end of the outdoor heat exchanger. at least a second on-off valve that closes when the first on-off valve is open and opens or closes when the first on-off valve is closed; and a refrigerant pressure reduction path that includes a pressure reduction mechanism and is connected in parallel to the second on-off valve. , an indoor unit operation detection section that detects each indoor unit's cooling and heating operation designation and its operation mode, and an outdoor unit refrigerant that detects the refrigerant temperature of the outdoor heat exchanger, which is detected by the indoor unit operation detection section. The first and second
The switching means is controlled to a cooling mode or a heating mode, and the air volume adjusting device is controlled according to the difference between the refrigerant temperature detected by the outdoor unit refrigerant temperature detection section and the refrigerant temperature set value for the condenser or the set value for the evaporator. and the refrigerant flow rate control valve, and the first switching means takes priority over other conditions when the refrigerant temperature detected by the outdoor unit temperature detection section is higher than a predetermined evaporator transfer setting value. and a heat exchange control section that controls the second on-off valve to close.