JP3170753B2 - Air conditioner and outdoor unit used for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pair type air conditioner having an indoor unit which can be used commonly with a multizone type and pair type air conditioners. SOLUTION: The air conditioner comprises one outdoor unit having a compressor 2 and an outdoor heat exchanger 4, one indoor unit 8 having an electronic expansion valve 10 and an indoor heat exchanger 9, a refrigerant circuit in which refrigerant discharged from the compressor 2, for example, in a cooling operation is condensed by the exchanger 4, expanded by the valve 10, evaporated by the exchanger 9 and returned to the compressor 2, and a control means 11 for controlling the valve 10 to the unit 8 and to the unit 1. Thus, number of types of the indoor units can be reduced to simplify production management and inventory management and further shorten a production developing period.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indoor unit having one outdoor unit.
The present invention relates to a pair-type air conditioner having an indoor unit that can be used in common by a pair-type air conditioner combining units and a multi-type air conditioner combining a plurality of indoor units with one outdoor unit.

[0002]

2. Description of the Related Art Conventionally, air conditioners are mainly of the pair type, but in recent years, multi-type air conditioners have been increasing for buildings. Until now, separate indoor units for pair type and multi type have been adopted, increasing the number of models, making product development and product management difficult. Therefore, there is a demand to reduce the number of indoor units by sharing the pair type and the multi type.

A conventional air conditioner is disclosed in Japanese Patent Application Laid-Open No. 60-62.
As described in Japanese Patent Application Publication No. 543, temperature detectors are provided on each of an air inlet side, an air outlet side, and a refrigerant inlet side of an indoor heat exchanger, and the outputs of these temperature detectors are used as outdoor temperature estimating devices on the indoor unit side. The compressor is controlled based on the output from the outdoor temperature estimating device. That is, the compressor of the outdoor unit is controlled by the temperature signal obtained only on the indoor unit side, thereby stabilizing the refrigeration cycle.

In another conventional air conditioner, a refrigeration cycle comprising a compressor, an indoor heat exchanger, an electric expansion valve, and an outdoor heat exchanger is disclosed in Japanese Patent Application Laid-Open No. Sho 60-226667. Then, the temperature of the compressor discharge gas is detected by a sensor, the signal of the sensor is taken into the indoor control device, and the electric expansion valve is controlled stepwise by the signal from the indoor control device. That is, the signal of the compressor discharge gas temperature of the outdoor unit is taken into the indoor unit control device, and the signal from the indoor side control device controls the valve opening of the electric expansion valve.

[0005]

In one air conditioner of the prior art, the compressor is controlled by estimating the temperature of the outdoor unit on the basis of the temperature detected by the indoor unit. It is necessary to change the control unit of the indoor unit when an outdoor unit with a variable capacity compressor is combined with an indoor unit with a variable capacity compressor. Becomes Further, the pair-type indoor unit for performing the temperature estimation cannot be used as a multi-type indoor unit. This is because the outdoor temperature cannot be estimated from the temperature information of a plurality of indoor units.

In another air conditioner of the prior art, when the temperature signal of the compressor of the outdoor unit is taken into the indoor control unit and the indoor expansion valve is controlled after the calculation, the control is exclusively for the pair type. In order to use the indoor unit as a multi-type indoor unit, it was necessary to change the indoor control device, and no consideration was given to sharing the indoor unit used for the pair type and the multi type. .

An object of the present invention is to provide a pair type air conditioner having an indoor unit that can be commonly used as a multi-type indoor unit.

[0008]

To achieve the above object, an air conditioner according to the present invention comprises a single outdoor unit having a compressor and an outdoor heat exchanger, an electronic expansion valve and an indoor heat exchanger. When the operation mode of the indoor unit is cooling, the refrigerant discharged from the compressor is condensed in the outdoor heat exchanger, expanded in the electronic expansion valve, and expanded in the indoor heat exchanger. Forms a refrigeration cycle that evaporates and returns to the compressor, while when the operation mode is heating, the refrigerant discharged from the compressor condenses in the indoor heat exchanger, expands in the electronic expansion valve, and performs outdoor heat exchange. A refrigeration cycle for evaporating in the heat exchanger and returning to the compressor, wherein the dedicated outdoor unit to which only the one indoor unit is connected is provided with control means for controlling an electronic expansion valve of the indoor unit. It is characterized by.

When the operation mode of the indoor unit is the cooling mode, the control means controls the temperature of each of the suction and blow-off air for the indoor heat exchange, the temperature of the refrigerant flowing into the indoor heat exchanger, and the refrigerant discharged from the compressor of the outdoor unit. The opening degree of the electronic expansion valve is calculated and controlled based on the temperature of the refrigerant, the temperature of the refrigerant flowing into the outdoor heat exchanger, and the like. Further, when the operation mode is heating, the control means controls the temperatures of the suction and blow-off air for indoor heat exchange,
Calculate the opening of the electronic expansion valve based on the temperature of the refrigerant flowing out of the indoor exchanger, the temperature of the refrigerant flowing into the outdoor heat exchanger, and the like,
Control.

[0010]

According to the present invention, the electronic expansion valve is incorporated in the indoor unit,
Since a pair type air conditioner is configured by providing control means for controlling the electronic expansion valve to the outdoor unit, this indoor unit is basically a multi-type air conditioner that requires control means for the electronic expansion valve in the outdoor unit. It can be commonly used for type air conditioners.

Therefore, in the pair type and the multi type indoor unit, not only the hardware such as the indoor heat exchanger and the electronic expansion valve but also the control software of the indoor unit can be commonly used. Conventionally, it was necessary to manage the inventory of an indoor unit as a pair with an outdoor unit of a pair type or an outdoor unit of a multi-type. However, according to the present invention, since the indoor units are common to each outdoor unit, inventory management is large. Can be simplified.

Further, the control means controls the opening of the electronic expansion valve based on the information on the temperature of the refrigerant and the air in the indoor unit and the outdoor unit, so that the operation efficiency of the pair type air conditioner can be improved. It becomes possible.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. The air conditioner of the embodiment shown in FIG. 1 is a pair type in which one indoor unit as an indoor unit is connected to one outdoor unit as an outdoor unit by piping. The outdoor unit 1 includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, and an accumulator 5, and the indoor unit 8 includes an indoor heat exchanger 9 and an electronic expansion valve 10.

In the refrigeration cycle at the time of cooling, the gas refrigerant is compressed to a high temperature and a high pressure by the compressor 2 of the outdoor unit 1, and from the four-way valve 3 via the liquid side connection pipe 6 to the outdoor heat exchanger 4.
Is condensed there to become a liquid refrigerant, and this liquid refrigerant is adiabatically expanded by the electronic expansion valve 10 of the indoor unit 8, then evaporated in the indoor heat exchanger 9, and the evaporated refrigerant passes through the gas side connection pipe 7. After returning to the outdoor unit 1 via the four-way valve 3, it is sent to the accumulator 5, where it is separated into gas and liquid and is sucked into the compressor 2. Thus, the air in the room is cooled during the evaporation of the refrigerant, and is provided for cooling.

On the other hand, in a refrigeration cycle during heating,
A refrigerant circuit that circulates in the opposite direction to the refrigerant circuit during cooling is formed. That is, the gas refrigerant compressed to a high temperature and a high pressure by the compressor 2 of the outdoor unit 1 is liquefied in the indoor heat exchanger 9 of the indoor unit 8 and adiabatically expanded by the electronic expansion valve 10. To return to the outdoor unit 1. Thus, when the refrigerant is liquefied in the indoor heat exchanger 9, the indoor air is warmed and provided for heating.

A temperature sensor for detecting a cycle temperature is attached to each component device forming the refrigeration cycle. In the outdoor unit 1, the temperature sensor 15 detects the temperature of the air sucked into the outdoor heat exchanger 4, the temperature sensor 16 detects the temperature of the liquid refrigerant flowing out of the outdoor heat exchanger 4 during cooling, and is discharged from the compressor. A temperature sensor 17 for detecting the temperature of the refrigerant is provided.
Then, the temperature sensor 18 for detecting the temperature of the refrigerant flowing into the indoor heat exchanger 9 during cooling, the temperature sensor 19 for detecting the temperature of the air sucked into the indoor heat exchanger 9, and the temperature of the air blown out from the indoor heat exchanger 9 Temperature sensor 20 for detecting
Is provided. Since the refrigerant flows in the opposite direction to the cooling operation during the heating, the temperature sensor 16 provided in the outdoor heat exchanger 4 indicates the temperature of the inflowing refrigerant vapor, and the temperature sensor 18 provided in the indoor heat exchanger 9 indicates the outflow. The temperature of the liquid refrigerant to be measured is measured.

The temperature sensors 18, 1 on the indoor unit 8 side
The signals from the control units 9 and 20 are taken into the indoor control unit 12, the signals are converted, and the signals are taken into the outdoor control unit 11 through the operation information circuit 14 as electric signals. In addition, operation information such as an operation / stop signal on the indoor unit 8 side, an operation mode of cooling / heating / blowing / defrosting, and a blowing tap signal is also taken into the outdoor controller 11 through the operation information circuit 14. The temperature sensors 15, 16, 1 on the outdoor unit 1 side
7 is taken into the outdoor controller 11 and converted into an electric signal by signal conversion. Further, the outdoor controller 11 uses the acquired indoor and outdoor temperature signals and operation information to
Electronic expansion valve 1 optimal for stabilizing the refrigeration cycle
An opening degree of 0 is calculated. An opening signal of the electronic expansion valve 10 is sent to the indoor side control device 12 through the operation command circuit 13 according to the calculated opening degree, and the signal is converted into a pulse signal there. Sending pulse signal.

Therefore, the indoor control unit 12 does not have a signal calculation function, but only the outdoor control unit 11 has a calculation function, so that the indoor unit can be used commonly for the pair type and the multi-type air conditioners. Becomes possible.
That is, the outdoor controller 11 has a control function of the electronic expansion valve 10 when the compressor 2 has a variable capacity and a control function of the electronic expansion valve 10 when the compressor 1 has a constant capacity.
The control method can be switched by the dip switch 22 shown in FIG. 2, the indoor unit 8 receives the electric signal from the outdoor control device 11, converts the signal, and outputs a pulse signal to the electronic expansion valve 10. Further, by installing the indoor control device 12 having a function of outputting indoor operation information to the outdoor control device 11 after signal conversion, the outdoor unit 1 having the compressor 2 having a variable capacity can be fixed to the outdoor unit 1. The same indoor unit 8 as the outdoor unit 1 equipped with the compressor can be used on the refrigeration cycle.
Also, the combination can be performed in the indoor and outdoor control. In FIG. 1, reference numeral 21 denotes a control signal circuit, and a capacity control signal by frequency change is transmitted from the outdoor controller 11 to the compressor 2 through the circuit 21.

FIG. 3 is a refrigeration cycle system diagram of a so-called multi-type air conditioner in which a plurality of indoor units 8a, 8b, 8c... Are connected to one outdoor unit 1. At least one of the indoor units 8a, 8b, 8c,... Is the same as the indoor unit 8 shown in FIG.
It is possible to standardize. Here, if the outdoor controller 11 controls, for example, three types of indoor units having different cooling and heating capacities, the pair-type indoor unit 8 is also made to be the same model as one of these three types of indoor units. Standardization becomes possible.

As described above, the indoor unit can be used in common for the pair type and the multi-type air conditioners. Therefore, the indoor unit and the outdoor unit can be distributed and sold in a conventional manner. Instead, the indoor unit can be sold separately. In addition, the components of the indoor unit can be standardized, and the number of components is reduced, so that the manufacturer can easily manage the components. In addition, since the same components are mass-produced, the cost of the components can be reduced.

Furthermore, only by performing a performance test or performance calculation in which the pair type indoor unit and the outdoor unit are combined, only the control change by the outdoor controller is performed, so that the multi-type outdoor unit can be connected to the outdoor unit. Since the combination is possible, it is possible to shorten a product development period.

[0022]

According to the present invention, a pair-type air conditioner is provided with an electronic expansion valve in the indoor unit and a control means for controlling the opening of the electronic expansion valve in the outdoor unit. This pair type indoor unit can be basically combined with a multi-type outdoor unit having electronic expansion valve control means, and the indoor unit can be shared.

Therefore, the number of indoor units can be reduced as compared with the conventional case, and production management, inventory management and the like can be simplified. Further, although the indoor unit and the outdoor unit have been conventionally distributed and sold as a pair, the indoor unit and the outdoor unit can be separately distributed and sold. Furthermore, the product development period can be shortened.

[Brief description of the drawings]

FIG. 1 is a refrigeration cycle system diagram of a pair type air conditioner according to one embodiment of the present invention.

FIG. 2 is a diagram showing a dip switch provided in an outdoor unit.

FIG. 3 is a diagram of a multi-type refrigeration cycle system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 indoor unit 2 compressor 3 four-way valve 4 outdoor heat exchanger 5 accumulator 8 indoor unit 9 indoor heat exchanger 10 electronic expansion valve 11 outdoor control device 12 indoor control device 15, 16, 17 temperature sensor 18, 19 , 20 Temperature sensor 22 Liquid tank

Continued on the front page (72) Inventor Kensaku Oguni 502, Kandachi-cho, Tsuchiura-shi, Ibaraki Machinery Research Laboratory, Hitachi, Ltd. Inventor Shunji Sasaki 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Inside the Shimizu Plant, Hitachi, Ltd. 390 Ichimuramatsu Inside the Shimizu Plant, Hitachi, Ltd. (56) References JP-A-64-79553 (JP, A) JP-A-2-85654 (JP, A) JP-A-63-73059 (JP, A) ( 58) Field surveyed (Int.Cl. ⁷ , DB name) F24F 11/02 102 F24F 11/02 F25B 1/00 304 F25B 41/06

Claims (2)

(57) [Claims] 1. An air conditioner including an outdoor unit having a compressor and an outdoor heat exchanger, and an indoor unit having an electronic expansion valve and an indoor heat exchanger, wherein the outdoor unit has a compressor.
Control function of the electronic expansion valve when the amount is variable ;
Controller for the electronic expansion valve when the compressor has a constant capacity
An air conditioner characterized by having noh . 2. An electronic expansion device having a compressor and an outdoor heat exchanger.
Can be connected with an indoor unit having a expansion valve and an indoor heat exchanger by piping
In the outdoor unit, the capacity of the compressor was made variable.
A first control function for controlling the electronic expansion valve;
When the compressor has a constant capacity, the electronic expansion valve is controlled.
A second control function to perform the first and second control functions.
A room provided with a switch for switching to one side
Outside machine.