JPH09280681A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately detect the degree of indoor heat exchange outlet supercooling upon heating operation with a simplified construction, and ensure highly effectual heating operation whatever installation conditions are by calculating as the degree of indoor heat exchange outlet supercooling a value obtained by subtracting liquid refrigerant temperature from saturation temperature corresponding to pressure yielded by subtracting pressure loss from discharge pressure. SOLUTION: A refrigerant circuit 33 is constructed by connecting through piping an outdoor unit 21 including a compressor 22 and an outdoor heat exchanger 24 and a plurality of indoor units each including indoor heat exchangers 29 (29a to 29d) and indoor expansion valves 28a to 28d, etc. Further, a discharge pressure sensor 34 and liquid refrigerant temperature sensors 35a to 35d are provided, and refrigerant pressure loss from the neighbourhood of the compressor 22 to the neighbourhood of the indoor heat exchanger 29 is estimated in a pressure loss estimation unit 37, and further saturation temperature corresponding to pressure yielded by subtracting pressure loss from the discharge pressure is estimated in a corrected saturation temperature estimation unit 38. A value obtained by subtracting liquid refrigerant temperature from the corrected saturation temperature is estimated by a corrected degree-of- supercooling estimation unit 39 as the degree of indoor heat exchange outlet supercooling, and the degree of opening of the indoor expansion valve is controlled such that the degree of supercooling falls within a substantially predetermined range.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】本発明は、空気調和機の改良
に関するもので、特に暖房運転時の過冷却度制御が可能
な空気調和機に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an air conditioner, and more particularly to an air conditioner capable of controlling the degree of subcooling during heating operation.

【０００２】[0002]

【従来の技術】従来の空気調和機については、さまざま
な提案がなされており、そのうち、複数台の室内ユニッ
トを有する従来例を図４を用いて、特に暖房運転時を中
心に説明する。2. Description of the Related Art Various proposals have been made for a conventional air conditioner. Among them, a conventional example having a plurality of indoor units will be described with reference to FIG.

【０００３】１は空気調和機の室外ユニットであり、圧
縮機２、四方弁３、室外熱交換器４、室外膨張弁５、室
外ファン６から成っている。An outdoor unit 1 of the air conditioner is composed of a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an outdoor expansion valve 5, and an outdoor fan 6.

【０００４】７ａ，７ｂ，７ｃ，７ｄは室内機であり、
それぞれ室内膨張弁８ａ，８ｂ，８ｃ，８ｄ、室内熱交
換器９ａ，９ｂ，９ｃ，９ｄ、室内ファン１０ａ，１０
ｂ，１０ｃ，１０ｄから成っている。[0004] 7a, 7b, 7c, 7d are indoor units,
Indoor expansion valves 8a, 8b, 8c, 8d, indoor heat exchangers 9a, 9b, 9c, 9d, indoor fans 10a, 10 respectively
b, 10c and 10d.

【０００５】そして、室外ユニット１と室内機７ａ，７
ｂ，７ｃ，７ｄは液管１１及びガス管１２によって環状
に接続され、冷媒回路１３を構成している。Then, the outdoor unit 1 and the indoor units 7a, 7
b, 7c, 7d are connected in a ring shape by a liquid pipe 11 and a gas pipe 12, and constitute a refrigerant circuit 13.

【０００６】また、１４は圧縮機２の吐出圧力を検出す
る吐出圧力センサー、１５ａ，１５ｂ，１５ｃ，１５ｄ
は各室内熱交換器の液側冷媒温度を検出する温度センサ
ーである。また、１６は吐出圧力センサーで検出した圧
力値から、その圧力相当の飽和温度を算出する飽和温度
算出器である。さらに、１７は飽和温度算出器１６で計
算された飽和温度と、温度センサー１５ａ，１５ｂ，１
５ｃ，１５ｄで検出した冷媒温度から各室内熱交換器９
ａ，９ｂ，９ｃ，９ｄの過冷却度を算出する過冷却度算
出器である。さらにまた、１８は過冷却度算出器１７か
ら出力された過冷却度とあらかじめ設定してある設定過
冷却度とを比較し、室内膨張弁８ａ，８ｂ，８ｃ，８ｄ
を開閉動作させる膨張弁制御器である。Reference numeral 14 denotes a discharge pressure sensor for detecting the discharge pressure of the compressor 2, 15a, 15b, 15c, 15d.
Is a temperature sensor for detecting the liquid-side refrigerant temperature of each indoor heat exchanger. Reference numeral 16 denotes a saturation temperature calculator that calculates a saturation temperature corresponding to the pressure from the pressure value detected by the discharge pressure sensor. Further, 17 is the saturation temperature calculated by the saturation temperature calculator 16 and the temperature sensors 15a, 15b, 1
Each indoor heat exchanger 9 is determined based on the refrigerant temperature detected in 5c and 15d.
This is a supercooling degree calculator that calculates the degree of supercooling of a, 9b, 9c, and 9d. Further, reference numeral 18 compares the degree of supercooling output from the degree of supercooling calculator 17 with a preset degree of supercooling, and determines whether the indoor expansion valves 8a, 8b, 8c, and 8d.
Is an expansion valve controller for opening and closing.

【０００７】次に、上記構成の多室型空気調和機の動作
について説明する。Next, the operation of the multi-room air conditioner having the above configuration will be described.

【０００８】暖房運転時は、圧縮機２で圧縮された高温
高圧ガスは四方弁３を介して室内ファン１０ａ，１０
ｂ，１０ｃ，１０ｄで送られた空気と室内熱交換器９
ａ，９ｂ，９ｃ，９ｄで熱交換して凝縮し、高温高圧の
液冷媒となって、室内膨張弁８ａ，８ｂ，８ｃ，８ｄで
減圧され、さらに室外膨張弁５で減圧され、室外熱交換
器４で蒸発して低温低圧のガスとなり、四方弁３を介し
て再び圧縮機２に戻る。During the heating operation, the high-temperature high-pressure gas compressed by the compressor 2 is passed through the four-way valve 3 to the indoor fans 10a, 10a.
Air sent by b, 10c, 10d and indoor heat exchanger 9
a, 9b, 9c, 9d heat-condenses and condenses to become a high-temperature high-pressure liquid refrigerant, which is decompressed by the indoor expansion valves 8a, 8b, 8c, 8d and further decompressed by the outdoor expansion valve 5 to perform outdoor heat exchange. It vaporizes in the vessel 4 to become a low temperature and low pressure gas, and returns to the compressor 2 again via the four-way valve 3.

【０００９】また、室内機のいずれかが停止状態にある
場合（例えば室内機７ａ）、その室内側膨張弁は微開と
なり（たとえば室内膨張弁８ａは微開）、停止室内機に
はほとんど冷媒が流れないように運転される。Further, when one of the indoor units is in a stopped state (for example, the indoor unit 7a), the indoor expansion valve thereof is slightly opened (for example, the indoor expansion valve 8a is slightly opened), and almost no refrigerant is contained in the stopped indoor unit. Is driven so that it does not flow.

【００１０】暖房運転時の室内膨張弁制御については次
のように行われる。サイクルを効率よく運転するために
は室内熱交換器９ａ，９ｂ，９ｃ，９ｄ出口の過冷却度
を適度な値とすることが必要であり、そのためにまず、
吐出圧力センサー１４で検出した圧力から飽和温度算出
器１６で飽和温度を算出する。The indoor expansion valve control during the heating operation is performed as follows. In order to operate the cycle efficiently, it is necessary to set the degree of supercooling at the outlet of the indoor heat exchangers 9a, 9b, 9c, 9d to an appropriate value.
The saturation temperature is calculated by the saturation temperature calculator 16 from the pressure detected by the discharge pressure sensor 14.

【００１１】さらに、温度センサー１５ａ，１５ｂ，１
５ｃ，１５ｄで検知した各室内熱交喚器９ａ，９ｂ，９
ｃ，９ｄの出口温度と、飽和温度算出器１６によって計
算された飽和温度との差から、過冷却度算出器１７を用
いて各室内熱交換器９ａ，９ｂ，９ｃ，９ｄの過冷却度
を算出する。Further, the temperature sensors 15a, 15b, 1
Each indoor heat exchanger 9a, 9b, 9 detected by 5c, 15d
From the difference between the outlet temperatures of c and 9d and the saturation temperature calculated by the saturation temperature calculator 16, the supercooling degree of each of the indoor heat exchangers 9a, 9b, 9c and 9d is calculated using the supercooling degree calculator 17. calculate.

【００１２】そしてまた、膨張弁制御器１８を用いて、
過冷却度算出器１７からの過冷却度と、あらかじめ設定
してある設定過冷却度とを比較し、過冷却度が大きい時
には室内膨張弁８ａ，８ｂ，８ｃ，８ｄを開方向に動作
させ、過冷却度が小さい時には室内膨張弁８ａ，８ｂ，
８ｃ，８ｄを閉方向に動作させることにより、室内熱交
換器９ａ，９ｂ，９ｃ，９ｄ出口の過冷却度を適度な値
に制御して運転される。Also, using the expansion valve controller 18,
The degree of supercooling from the degree of supercooling calculator 17 is compared with a preset degree of supercooling, and when the degree of supercooling is large, the indoor expansion valves 8a, 8b, 8c, 8d are operated in the opening direction, When the degree of subcooling is small, the indoor expansion valves 8a, 8b,
By operating 8c and 8d in the closing direction, the operation is performed with the degree of supercooling at the outlet of the indoor heat exchangers 9a, 9b, 9c and 9d controlled to an appropriate value.

【００１３】こうすることにより、吐出圧力センサー１
４を一つ設けるだけで、各室内熱交換器９ａ，９ｂ，９
ｃ，９ｄ出口の過冷却度を適度な値に制御して効率の良
い運転を行おうとするものである。By doing so, the discharge pressure sensor 1
4 and each indoor heat exchanger 9a, 9b, 9
The supercooling degree at the outlets c and 9d is controlled to an appropriate value to perform an efficient operation.

【００１４】一方、冷房運転時は、圧縮機２で圧縮され
た高温高圧ガスは四方弁３を介して室外熱交換器４で凝
縮し、高圧の液冷媒となり、室外膨張弁５を介して室内
膨張弁８ａ，８ｂ，８ｃ，８ｄで減圧され、室内ファン
１０ａ，１０ｂ，１０ｃ，１０ｄで送られた空気と室内
熱交換器９ａ，９ｂ，９ｃ，９ｄで熱交換して蒸発し、
低温低圧のガスとなって、四方弁３を介して再び圧縮機
２に戻る。この時、室内機のいずれかが停止状態にある
場合（例えば室内機７ａ）、その室内側膨張弁は閉じら
れ（たとえば室内膨張弁８ａは閉）、停止室内機には冷
媒は流れないように運転される。On the other hand, during the cooling operation, the high-temperature high-pressure gas compressed by the compressor 2 is condensed in the outdoor heat exchanger 4 via the four-way valve 3 to become a high-pressure liquid refrigerant, and the indoor expansion valve 5 is opened. Air decompressed by the expansion valves 8a, 8b, 8c, 8d and exchanged with the air sent by the indoor fans 10a, 10b, 10c, 10d by the indoor heat exchangers 9a, 9b, 9c, 9d, and evaporated.
It becomes low-temperature low-pressure gas, and returns to the compressor 2 again via the four-way valve 3. At this time, if any of the indoor units is in the stopped state (for example, the indoor unit 7a), the indoor expansion valve is closed (for example, the indoor expansion valve 8a is closed), and the refrigerant does not flow to the stopped indoor unit. Be driven.

【００１５】冷房運転時においても、暖房運転時と同様
に高効率な運転を行うために室内膨張弁８ａ，８ｂ，８
ｃ，８ｄの制御が必要となるが、ここではその詳細は省
略する。In the cooling operation, the indoor expansion valves 8a, 8b, 8 are provided in order to operate as efficiently as in the heating operation.
Control of c and 8d is required, but the details are omitted here.

【００１６】[0016]

【発明が解決しようとする課題】これら空気調和機にお
いては、機器を設置する建物の構造によって、室外ユニ
ットと室内ユニットとを接続する接続配管の長さが大き
く変化し、短いものでは数ｍ、長いものでは１００ｍを
越えるものも珍しくないのが現実である。In these air conditioners, the length of the connecting pipe connecting the outdoor unit and the indoor unit varies greatly depending on the structure of the building in which the equipment is installed. In reality, it is not unusual for long ones to be longer than 100m.

【００１７】また、近年の高層ビルへの機器設置に対し
ても場所の制約によって、室外ユニットが屋上設置のも
のや、あるいは地上設置、中間階のベランダ設置のもの
など多種多様となっている。Also, due to the restrictions on the location of equipment installed in high-rise buildings in recent years, there are various types such as outdoor units installed on the rooftop, ground units, and verandas on the middle floor.

【００１８】一方、空気調和機としては安価で高効率な
システムが要求されており、高効率な運転を行うために
は熱交換器の過熱度や過冷却度を正確に検知することが
必要となる。しかし、製品の価格の面からは圧力センサ
ーや温度センサーなどの検知手段はできるだけ用いない
ことが望ましいという相反する方向となっている。On the other hand, an inexpensive and highly efficient system is required for the air conditioner, and it is necessary to accurately detect the degree of superheat or the degree of subcooling of the heat exchanger in order to perform highly efficient operation. Become. However, from the viewpoint of the price of the product, it has been a conflicting direction that it is desirable that detection means such as a pressure sensor and a temperature sensor be not used as much as possible.

【００１９】前記従来の空気調和機においては、暖房運
転時に、室内熱交換器出口の過冷却度を検出する場合
に、圧縮機の出口に設けた吐出圧力センサーで検出した
圧力から飽和温度を算出し、室内熱交換器出口温度との
差温から過冷却度を算出していたため、圧縮機から室内
熱交換器の間の圧損を考慮することができず、そのため
正確な過冷却度を検知できないばかりか、これら種々の
設置状況においては過冷却度が検知した値と真の値とが
大きくことなることがしばしば起こり、そのために過冷
却度が適度な値とならず、性能が劣化していた。In the conventional air conditioner, when the degree of subcooling at the outlet of the indoor heat exchanger is detected during heating operation, the saturation temperature is calculated from the pressure detected by the discharge pressure sensor provided at the outlet of the compressor. However, since the degree of supercooling was calculated from the temperature difference from the outlet temperature of the indoor heat exchanger, the pressure loss between the compressor and the indoor heat exchanger cannot be taken into consideration, and therefore the degree of supercooling cannot be accurately detected. Not only that, in these various installation situations, the detected value and the true value of the degree of supercooling often differ greatly, so that the degree of supercooling did not reach an appropriate value and the performance deteriorated. .

【００２０】また、これを防止するために、室内機に圧
力センサーを設けたりするものもあったが、圧力センサ
ーが高価であり、安価、高効率化という空調機の要望を
満足することが困難であった。In order to prevent this, some indoor units are provided with a pressure sensor, but the pressure sensor is expensive, and it is difficult to satisfy the demand for an air conditioner that is inexpensive and highly efficient. Met.

【００２１】本発明は、かかる従来の空気調和機の不具
合点を解消するためのものであり、簡単な構成で暖房運
転時の室内熱交換器出口過冷却度を正確に検知して、ど
のような設置状況においても、高効率な暖房運転が可能
な空気調和機を提供することを目的とするものである。The present invention is intended to solve the problems of the conventional air conditioner, and how to accurately detect the degree of subcooling at the outlet of the indoor heat exchanger during the heating operation with a simple structure. It is an object of the present invention to provide an air conditioner capable of highly efficient heating operation even under various installation conditions.

【００２２】[0022]

【課題を解決するための手段】本発明になる空気調和機
は、駆動される圧縮機、四方弁、室外熱交換器、室外膨
張弁などを構成要素としてなる室外ユニットと、室内熱
交換器、室内膨張弁などを構成要素としてなる１台以上
の室内ユニットとを接続配管で接続して冷媒回路を構成
し、前記圧縮機の吐出圧力を検出する吐出圧力検知手段
と、前記室内熱交換器の液冷媒温度を検出する液冷媒温
度検出手段と、前記圧縮機近傍から前記室内熱交換器近
傍の間の冷媒圧損を算出する圧損算出手段と、前記吐出
圧力から前記圧損を減じた圧力相当の飽和温度を算出す
る補正飽和温度算出手段を設け、さらに前記補正飽和温
度算出手段で算出した飽和温度から前記液冷媒温度検出
手段で検出される温度を減じた値を前記室内熱交出口過
冷却度として算出する補正過冷却度算出手段と、前記過
冷却度が略一定の範囲の値となるように前記室内膨張弁
開度を制御する膨張弁制御器を備えたことを特徴とする
ものである。An air conditioner according to the present invention includes an outdoor unit having a driven compressor, a four-way valve, an outdoor heat exchanger, an outdoor expansion valve, and the like, and an indoor heat exchanger, A discharge pressure detecting means for detecting a discharge pressure of the compressor and a refrigerant circuit by connecting at least one indoor unit having an indoor expansion valve or the like as a constituent element with a connecting pipe, and the indoor heat exchanger. Liquid refrigerant temperature detecting means for detecting the liquid refrigerant temperature, pressure loss calculating means for calculating the refrigerant pressure loss between the vicinity of the compressor and the indoor heat exchanger, and saturation equivalent to the pressure obtained by subtracting the pressure loss from the discharge pressure. A value obtained by subtracting the temperature detected by the liquid refrigerant temperature detection means from the saturation temperature calculated by the correction saturation temperature calculation means is provided as the indoor heat exchange outlet supercooling degree. Calculation A correction supercooling degree calculating unit that, the is characterized in that the degree of supercooling with an inflation valve controller for controlling the indoor expansion valve to a value substantially constant range.

【００２３】また、同じく本発明になる空気調和機は、
圧縮機、四方弁、室外熱交換器、室外膨張弁などを構成
要素としてなる室外ユニットと、室内熱交換器、室内膨
張弁などを構成要素としてなる１台以上の室内ユニット
とを接続配管で接続して冷媒回路を構成し、前記接続配
管の配管長範囲に応じて設定値を段階的に切り換えるこ
とができる配管長範囲スイッチを設け、さらに前記圧縮
機の吐出圧力を検出する吐出圧力検知手段と、前記圧縮
機の運転周波数を検知する運転周波数検知手段と、前記
室内熱交換器の液冷媒温度を検出する液冷媒温度検出手
段と、前記運転周波数の値と前記配管長範囲スイッチの
設定値を用いて前記圧縮機近傍から前記室内熱交換器近
傍の間の冷媒圧損を算出する圧損算出手段と、前記吐出
圧力から前記圧損を減じた圧力相当の飽和温度を算出す
る補正飽和温度算出手段を設け、さらに前記補正飽和温
度算出手段で算出した飽和温度から前記液冷媒温度検出
手段で検出される温度を減じた値を前記室内熱交出口過
冷却度として算出する補正過冷却度算出手段と、前記過
冷却度が略一定の範囲の値となるように前記室内膨張弁
開度を制御する膨張弁制御器を備えたことを特徴とする
ものである。The air conditioner according to the present invention is also
An outdoor unit that has a compressor, a four-way valve, an outdoor heat exchanger, an outdoor expansion valve, etc. as its constituent elements and one or more indoor units that have an indoor heat exchanger, an indoor expansion valve, etc. as its constituent elements are connected by connecting piping. A refrigerant circuit is configured to provide a pipe length range switch capable of stepwise switching a set value according to the pipe length range of the connection pipe, and further a discharge pressure detection means for detecting the discharge pressure of the compressor. , An operating frequency detecting means for detecting the operating frequency of the compressor, a liquid refrigerant temperature detecting means for detecting the liquid refrigerant temperature of the indoor heat exchanger, a value of the operating frequency and a set value of the pipe length range switch Pressure loss calculation means for calculating the refrigerant pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger using the correction saturation temperature calculation for calculating the saturation temperature corresponding to the pressure obtained by subtracting the pressure loss from the discharge pressure. A correction supercooling degree calculating means for calculating a value obtained by subtracting a temperature detected by the liquid refrigerant temperature detecting means from a saturation temperature calculated by the correction saturation temperature calculating means as the indoor heat exchange outlet supercooling degree And an expansion valve controller that controls the opening degree of the indoor expansion valve so that the degree of supercooling becomes a value in a substantially constant range.

【００２４】さらに、同じく本発明になる空気調和機
は、圧縮機、四方弁、室外熱交換器、室外膨張弁などを
構成要素としてなる室外ユニットと、室内熱交換器、室
内膨張弁などを構成要素としてなる１台以上の室内ユニ
ットとを接続配管で接続して冷媒回路を構成し、前記接
続配管の配管長に応じて設定値を設定することができる
配管長設定スイッチを設け、さらに前記圧縮機の吐出圧
力を検出する吐出圧力検知手段と、前記圧縮機の運転周
波数を検知する運転周波数検知手段と、前記室内熱交換
器の液冷媒温度を検出する液冷媒温度検出手段と、前記
運転周波数の値と前記配管長設定スイッチの設定値を用
いて前記圧縮機近傍から前記室内熱交換器近傍の間の冷
媒圧損を算出する圧損算出手段と、前記吐出圧力から前
記圧損を減じた圧力相当の飽和温度を算出する補正飽和
温度算出手段を設け、さらに前記補正飽和温度算出手段
で算出した飽和温度から前記液冷媒温度検出手段で検出
される温度を減じた値を前記室内熱交出口過冷却度とし
て算出する補正過冷却度算出手段と、前記過冷却度が略
一定の範囲の値となるように前記室内膨張弁開度を制御
する膨張弁制御器を備えたことを特徴とするものであ
る。Furthermore, the air conditioner according to the present invention also comprises an outdoor unit having a compressor, a four-way valve, an outdoor heat exchanger, an outdoor expansion valve and the like as components, an indoor heat exchanger, an indoor expansion valve and the like. A refrigerant circuit is configured by connecting one or more indoor units as elements with a connecting pipe, and a pipe length setting switch capable of setting a set value according to the pipe length of the connecting pipe is provided, and the compression circuit is further provided. Discharge pressure detecting means for detecting the discharge pressure of the machine, operating frequency detecting means for detecting the operating frequency of the compressor, liquid refrigerant temperature detecting means for detecting the liquid refrigerant temperature of the indoor heat exchanger, and the operating frequency Value and the set value of the pipe length setting switch, the pressure loss calculating means for calculating the refrigerant pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger, and the pressure obtained by subtracting the pressure loss from the discharge pressure. Corrected saturation temperature calculation means for calculating the saturation temperature is provided, and a value obtained by subtracting the temperature detected by the liquid refrigerant temperature detection means from the saturation temperature calculated by the corrected saturation temperature calculation means is used as the indoor heat exchange outlet temperature. A correction subcooling degree calculating means for calculating as a cooling degree, and an expansion valve controller for controlling the indoor expansion valve opening degree so that the subcooling degree has a value in a substantially constant range are provided. Is.

【００２５】[0025]

【発明の実施の形態】以下、本発明の実施の形態につい
て、図１から図３を用いて説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

【００２６】（実施の形態１)図１は本発明の請求項１
および２記載の空気調和機の一実施の形態であり、冷凍
サイクルの回路図の概略を示しており、特に本発明の主
眼となる暖房運転時を中心に説明する。(Embodiment 1) FIG. 1 shows the first aspect of the present invention.
2 is an embodiment of the air conditioner described in (2) and (2) above, showing a schematic circuit diagram of a refrigerating cycle, and particularly in the heating operation which is the main object of the present invention.

【００２７】２１は空気調和機の室外ユニットであり、
圧縮機２２、四方弁２３、室外熱交換器２４、室外膨張
弁２５、室外ファン２６から成っている。Reference numeral 21 is an outdoor unit of the air conditioner,
It is composed of a compressor 22, a four-way valve 23, an outdoor heat exchanger 24, an outdoor expansion valve 25, and an outdoor fan 26.

【００２８】２７ａ，２７ｂ，２７ｃ，２７ｄは室内機
であり、それぞれ室内膨張弁２８ａ，２８ｂ，２８ｃ，
２８ｄ、室内熱交換器２９ａ，２９ｂ，２９ｃ，２９
ｄ、室内ファン３０ａ，３０ｂ，３０ｃ，３０ｄから成
っている。27a, 27b, 27c, 27d are indoor units, and indoor expansion valves 28a, 28b, 28c,
28d, indoor heat exchangers 29a, 29b, 29c, 29
d, indoor fans 30a, 30b, 30c, 30d.

【００２９】そして、室外ユニット２１と室内機２７
ａ，２７ｂ，２７ｃ，２７ｄは接続配管（液管３１及び
ガス管３２）によって環状に接続され、冷媒回路３３を
構成しており、冷凍サイクルおよび冷媒の流れは従来例
と同様である。The outdoor unit 21 and the indoor unit 27
a, 27b, 27c, 27d are connected in a ring by connecting pipes (liquid pipe 31 and gas pipe 32) to form a refrigerant circuit 33, and the refrigeration cycle and the flow of the refrigerant are the same as in the conventional example.

【００３０】また、３４は圧縮機２２の吐出圧力を検出
する吐出圧力センサー、３５ａ，３５ｂ，３５ｃ，３５
ｄは各室内熱交換器の液側冷媒温度を検出する温度セン
サー、３６は圧縮機２２の運転周波数を検知する周波数
センサーである。Further, 34 is a discharge pressure sensor for detecting the discharge pressure of the compressor 22, and 35a, 35b, 35c, 35.
Reference numeral d is a temperature sensor that detects the liquid-side refrigerant temperature of each indoor heat exchanger, and 36 is a frequency sensor that detects the operating frequency of the compressor 22.

【００３１】また、３７は周波数センサー３６で検出し
た周波数の値から、圧縮機２２と室内熱交換器２９ａ，
２９ｂ，２９ｃ，２９ｄの間の圧損を計算する圧損算出
器、３８は吐出圧力センサー３４で検知した吐出圧力と
圧損算出器３７で求まった圧損を減じて、その圧力相当
の飽和温度を算出する補正飽和温度算出器である。Further, reference numeral 37 indicates from the value of the frequency detected by the frequency sensor 36 that the compressor 22 and the indoor heat exchanger 29a,
A pressure loss calculator for calculating the pressure loss between 29b, 29c, and 29d, and 38 is a correction for subtracting the discharge pressure detected by the discharge pressure sensor 34 and the pressure loss found by the pressure loss calculator 37 to calculate a saturation temperature corresponding to the pressure. It is a saturation temperature calculator.

【００３２】さらに、３９は補正飽和温度算出器３８で
計算された飽和温度と温度センサー３５ａ，３５ｂ，３
５ｃ，３５ｄで検出した冷媒温度から各室内熱交換器２
９ａ，２９ｂ，２９ｃ，２９ｄの過冷却度を算出する補
正過冷却度算出器である。Further, 39 is the saturation temperature calculated by the correction saturation temperature calculator 38 and the temperature sensors 35a, 35b, 3
5c and 35d, each indoor heat exchanger 2
This is a corrected supercooling degree calculator that calculates the supercooling degrees of 9a, 29b, 29c, and 29d.

【００３３】さらにまた、４０は補正過冷却度算出器３
９から出力された過冷却度とあらかじめ設定してある設
定過冷却度とを比較し、室内膨張弁２８ａ，２８ｂ，２
８ｃ，２８ｄを開閉動作させる膨張弁制御器である。Furthermore, 40 is a corrected supercooling degree calculator 3
The supercooling degree output from 9 is compared with the preset supercooling degree, and the indoor expansion valves 28a, 28b, 2
An expansion valve controller that opens and closes 8c and 28d.

【００３４】次に、上記構成の空気調和機の動作につい
て暖房時を中心に説明する。Next, the operation of the air conditioner configured as described above will be described focusing on heating.

【００３５】暖房運転時は、圧縮機２２で圧縮された高
温高圧ガスは四方弁２３を介して室内ファン３０ａ，３
０ｂ，３０ｃ，３０ｄで送られた空気と室内熱交換器２
９ａ，２９ｂ，２９ｃ，２９ｄで熱交換して凝縮し、高
温高圧の液冷媒となって、室内膨張弁２８ａ，２８ｂ，
２８ｃ，２８ｄで減圧され、室外膨張弁２５で減圧さ
れ、室外熱交換器２４で蒸発して低温低圧のガスとな
り、四方弁２３を介して再び圧縮機２２に戻る。During the heating operation, the high-temperature high-pressure gas compressed by the compressor 22 passes through the four-way valve 23 and the indoor fans 30a, 3
Air sent by 0b, 30c, 30d and indoor heat exchanger 2
9a, 29b, 29c, and 29d exchange heat to condense and become a high-temperature high-pressure liquid refrigerant, and the indoor expansion valves 28a, 28b,
It is decompressed by 28c and 28d, decompressed by the outdoor expansion valve 25, evaporated in the outdoor heat exchanger 24 to become a low-temperature low-pressure gas, and returns to the compressor 22 again via the four-way valve 23.

【００３６】また、室内機のいずれかが停止状態にある
場合（例えば室内機２７ａ）、その室内側膨張弁は微開
となり（たとえば室内膨張弁２８ａは微開）、停止室内
機にはほとんど冷媒が流れないように運転される。When any of the indoor units is in a stopped state (for example, the indoor unit 27a), the indoor expansion valve thereof is slightly opened (for example, the indoor expansion valve 28a is slightly opened), and almost no refrigerant is contained in the stopped indoor unit. Is driven so that it does not flow.

【００３７】次に、暖房運転時の室内膨張弁制御につい
ては次のように行われる。Next, the indoor expansion valve control during the heating operation is performed as follows.

【００３８】暖房サイクルを効率よく運転するためには
室内熱交換器２９ａ，２９ｂ，２９ｃ，２９ｄ出口の過
冷却度を適度な値とすることが必要であり、そのために
まず、吐出圧力センサー３４で吐出圧力(Ｐｄ)を検出す
る。次に、圧損算出器３７により圧縮機２２から室内熱
交換器２９ａ，２９ｂ，２９ｃ，２９ｄの間の圧力損失
(△Ｐ)を、周波数センサー３６で検知した圧縮機の運転
周波数(ｆ)の関数としてたとえば次式で計算する。In order to operate the heating cycle efficiently, it is necessary to set the subcooling degree at the outlets of the indoor heat exchangers 29a, 29b, 29c, 29d to an appropriate value. For that purpose, first, the discharge pressure sensor 34 is used. The discharge pressure (Pd) is detected. Next, the pressure loss calculator 37 causes the pressure loss between the compressor 22 and the indoor heat exchangers 29a, 29b, 29c, 29d.
(ΔP) is calculated as a function of the operating frequency (f) of the compressor detected by the frequency sensor 36, for example, by the following equation.

【００３９】[0039]

【数１】△Ｐ＝Ａ×(ｆ)＋Ｂ Ａ，Ｂは定数 ここにおいて、圧縮機２２から室内熱交換器２９ａ，２
９ｂ，２９ｃ，２９ｄ入口の間の冷媒の状態は、圧縮機
２２の吐出ガスであるのでガス単相の流れであり、この
場合の圧損は冷媒循環量に大きく関わることがよく知ら
れている。## EQU1 ## ΔP = A × (f) + B A and B are constants, where the compressor 22 to the indoor heat exchangers 29a and 2
It is well known that the state of the refrigerant between the inlets 9b, 29c, 29d is a gas single-phase flow because it is the discharge gas of the compressor 22, and the pressure loss in this case is largely related to the refrigerant circulation amount.

【００４０】また、冷媒循環量は圧縮機運転周波数に大
きく関わることも知られているので、上式のように圧損
を圧縮機２２の関数とすることにより、圧縮機２２から
室内熱交換器２９ａ，２９ｂ，２９ｃ，２９ｄの間の圧
損を精度良く推定できるものである。It is also known that the refrigerant circulation amount has a great influence on the compressor operating frequency. Therefore, by making the pressure loss a function of the compressor 22 as in the above equation, the compressor 22 is connected to the indoor heat exchanger 29a. , 29b, 29c, 29d can be accurately estimated.

【００４１】次に、算出した圧損(△Ｐ)と吐出圧力(Ｐ
ｄ）を補正飽和温度算出器３８に入力し、室内熱交換器
２９ａ，２９ｂ，２９ｃ，２９ｄの出口圧力（Ｐｈ）を
次式で算出する。Next, the calculated pressure loss (ΔP) and discharge pressure (P
d) is input to the corrected saturation temperature calculator 38, and the outlet pressure (Ph) of the indoor heat exchangers 29a, 29b, 29c, 29d is calculated by the following equation.

【００４２】[0042]

【数２】Ｐｈ＝Ｐｄ−△Ｐ ここにおいては、室内熱交換器２９ａ，２９ｂ，２９
ｃ，２９ｄのガス側の圧力を算出していることになる
が、暖房時に凝縮器となる熱交換器の圧損は無視できる
ほど小さいことを確認しているので、この場合には室内
熱交換器２９ａ，２９ｂ，２９ｃ，２９ｄのガス側圧力
（入口）も液側圧力（出口）もほぼ同等と扱うことが可
能である。## EQU00002 ## Ph = Pd-.DELTA.P Here, the indoor heat exchangers 29a, 29b, 29
Although the gas side pressures of c and 29d are calculated, it has been confirmed that the pressure loss of the heat exchanger that serves as the condenser during heating is so small that it can be ignored, so in this case, the indoor heat exchanger is used. The gas side pressure (inlet) and the liquid side pressure (outlet) of 29a, 29b, 29c, and 29d can be treated as substantially equal.

【００４３】次に、ここでは与えられた圧力値に対する
飽和液温度を同時に算出し、室内熱交換器２９ａ，２９
ｂ，２９ｃ，２９ｄの圧力（Ｐｈ）に対する飽和液温度
(Ｔｓａｔ)を算出することができる。Next, here, the saturated liquid temperature for a given pressure value is calculated at the same time, and the indoor heat exchangers 29a, 29 are
Saturated liquid temperature with respect to pressure (Ph) of b, 29c and 29d
(Tsat) can be calculated.

【００４４】さらに、各室内熱交換器２９ａ，２９ｂ，
２９ｃ，２９ｄの液冷媒温度（Ｔｈ）を各温度センサー
３５ａ，３５ｂ，３５ｃ，３５ｄで検知して、飽和液温
度(Ｔｓａｔ）と共に補正過冷却度算出手段に入力し、
各室内熱交換器２９ａ，２９ｂ，２９ｃ，２９ｄの過冷
却度（ＳＣ）を次式で算出する。Further, each indoor heat exchanger 29a, 29b,
The liquid refrigerant temperatures (Th) of 29c and 29d are detected by the temperature sensors 35a, 35b, 35c and 35d, and are input to the corrected supercooling degree calculation means together with the saturated liquid temperature (Tsat).
The degree of supercooling (SC) of each indoor heat exchanger 29a, 29b, 29c, 29d is calculated by the following formula.

【００４５】[0045]

【数３】ＳＣ＝Ｔｓａｔ−Ｔｈ ここでは、圧損が精度良く算出されているので、室内熱
交換器２９ａ，２９ｂ，２９ｃ，２９ｄの圧力（Ｐ
ｈ）、飽和液温度(Ｔｓａｔ）の精度も高く、過冷却度
（ＳＣ）も精度良く算出できる。## EQU3 ## SC = Tsat-Th Here, since the pressure loss is calculated accurately, the pressure (P
h), the accuracy of the saturated liquid temperature (Tsat) is also high, and the supercooling degree (SC) can also be calculated accurately.

【００４６】次に、過冷却度のデータは膨張弁制御器４
０に入力され、ここにおいては、あらかじめ冷凍サイク
ルを効率よく運転可能な過冷却度の値を設定して入力し
ておき、各室内熱交換器２９ａ，２９ｂ，２９ｃ，２９
ｄの液冷媒過冷却度（ＳＣ）と比較して、過冷却度が大
きい場合にはそれに対応する室内膨張弁を開方向に動作
させ、逆に過冷却度が小さい場合にはそれに対応する室
内膨張弁を閉方向に動作させことにより、各室内熱交換
器２９ａ，２９ｂ，２９ｃ，２９ｄの過冷却度は効率の
高い状態で運転されることになる。Next, the data of the degree of supercooling is used for the expansion valve controller 4
In this case, a value of the degree of supercooling at which the refrigeration cycle can be efficiently operated is set and input in advance, and each of the indoor heat exchangers 29a, 29b, 29c, 29
Compared with the liquid refrigerant supercooling degree (d) of d, when the supercooling degree is large, the corresponding indoor expansion valve is operated in the opening direction, and conversely, when the supercooling degree is small, the corresponding indoor expansion valve is operated. By operating the expansion valve in the closing direction, the degree of supercooling of each indoor heat exchanger 29a, 29b, 29c, 29d is operated in a highly efficient state.

【００４７】このように、圧縮機２２から各室内熱交換
器２９ａ，２９ｂ，２９ｃ，２９ｄの間の接続配管の圧
損を圧縮機２２の運転周波数の関数として算出すること
により、室内熱交換器２９ａ，２９ｂ，２９ｃ，２９ｄ
の実際の圧力を、計測することなく、真値に近い圧力を
推定することが可能となるので、過冷却度を正確に補正
して算出することができ、どのような運転周波数の状態
においても設定した過冷却度に制御することができ、常
に高効率な運転が可能となるものである。Thus, by calculating the pressure loss of the connecting pipe between the compressor 22 and each of the indoor heat exchangers 29a, 29b, 29c, 29d as a function of the operating frequency of the compressor 22, the indoor heat exchanger 29a. , 29b, 29c, 29d
Since it is possible to estimate the pressure close to the true value without measuring the actual pressure of, the degree of subcooling can be accurately corrected and calculated, and at any operating frequency state. The degree of supercooling that has been set can be controlled, and highly efficient operation is always possible.

【００４８】なお、ここで用いた圧損算出器３７による
圧力損失(△Ｐ)は運転周波数(ｆ)の１次の関数としての
みならず、高次の式や一定値も本発明に含まれることは
言うまでもない。It should be noted that the pressure loss (ΔP) by the pressure loss calculator 37 used here is not only a linear function of the operating frequency (f), but also higher-order expressions and constant values are included in the present invention. Needless to say.

【００４９】また、本実施の形態では冷媒の種類につい
ては何も述べていないが、空調用で主流のＨＣＦＣ２２
や、ＨＦＣ冷媒、ＨＦＣ混合冷媒においても、その効果
は全く同じものであり、これらも本発明に含まれるもの
である。In the present embodiment, no mention is made of the type of refrigerant, but the mainstream HCFC 22 for air conditioning is used.
The same effect can be obtained with the HFC refrigerant and the HFC mixed refrigerant, and these are also included in the present invention.

【００５０】一方、冷房運転時については、本発明の主
眼ではないので説明は省略する。On the other hand, the description of the cooling operation is omitted because it is not the main purpose of the present invention.

【００５１】（実施の形態２)図２は本発明の請求項３
および４記載の空気調和機の一実施の形態であり、冷凍
サイクルの回路図の概略を示しており、特に本発明の主
眼となる暖房運転時を中心に説明する。(Embodiment 2) FIG. 2 shows claim 3 of the present invention.
2 is an embodiment of the air conditioner described in (4) and (4), and shows a schematic circuit diagram of a refrigerating cycle. Particularly, a heating operation, which is the main object of the present invention, will be mainly described.

【００５２】また、図１に示した実施の形態１と構成、
作用が同様のものについては同一番号で記し、詳細な説
明は省略する。Further, the configuration of the first embodiment shown in FIG.
The same operation is denoted by the same reference numeral, and the detailed description is omitted.

【００５３】ここにおいては、接続配管（液管３１及び
ガス管３２）の配管長の範囲に応じて、設定値（ａ）を
段階的に切り換えることができる配管長範囲スイッチ５
０および室外ユニット２１と前記室内ユニット２７ａ，
２７ｂ，２７ｃ，２７ｄとの相対的な位置関係に応じて
設定値（ｂ）を設定することのできる高低差スイッチ５
１をそれぞれ室外ユニット１に備えている。Here, the pipe length range switch 5 is capable of stepwise changing the set value (a) according to the pipe length range of the connection pipes (the liquid pipe 31 and the gas pipe 32).
0 and the outdoor unit 21 and the indoor unit 27a,
Height difference switch 5 capable of setting a set value (b) according to the relative positional relationship with 27b, 27c, 27d
1 are provided in the outdoor unit 1 respectively.

【００５４】本実施の形態においては、これらの設定値
はたとえば次表のようにする。In the present embodiment, these set values are set as shown in the following table.

【００５５】[0055]

【表１】 これらの設定値（ａ），（ｂ）を、吐出圧力センサー３
４からの吐出圧力(Ｐｄ)データおよび周波数センサー３
６で検知した圧縮機の運転周波数(ｆ)データと共に圧損
算出器３７に送り、圧縮機２２から室内熱交換器２９
ａ，２９ｂ，２９ｃ，２９ｄの間の圧力損失(△Ｐ)をた
とえば次式のように算出する。[Table 1] These set values (a) and (b) are used as the discharge pressure sensor 3
Discharge pressure (Pd) data from 4 and frequency sensor 3
The operating frequency (f) data of the compressor detected in 6 is sent to the pressure loss calculator 37, and the compressor 22 sends the indoor heat exchanger 29.
The pressure loss (ΔP) between a, 29b, 29c and 29d is calculated, for example, by the following equation.

【００５６】[0056]

【数４】△Ｐ＝ａ×（Ａ×(ｆ)＋Ｂ）＋ｂ
Ａ，Ｂは定数 すなわち、圧損は配管長が長くなるほど大きくなること
は言うまでもなく、このように配管長範囲によって補正
できるような設定値（ａ）を設け、圧損と略比例した関
係を持たせることにより、圧損の精度が格段に向上す
る。[Expression 4] ΔP = a × (A × (f) + B) + b
It is needless to say that A and B are constants, that is, the pressure loss increases as the pipe length becomes longer, and thus, the set value (a) that can be corrected according to the pipe length range should be provided to have a relationship approximately proportional to the pressure loss. As a result, the accuracy of pressure loss is significantly improved.

【００５７】また、暖房運転時のガス管３２の冷媒流れ
を考えると、室外ユニット２１が室内ユニット２７ａ，
２７ｂ，２７ｃ，２７ｄより相対的に上にある場合には
ガス冷媒が下向きに流れ、下にある場合（上向き流れ）
よりも重力の影響で接続配管中の圧損は小さくなるた
め、高低差スイッチ５１の設定値（ｂ）を設けて補正を
加えることにより、重力も考慮した圧損を算出できるの
で精度がさらに向上する。Considering the refrigerant flow in the gas pipe 32 during the heating operation, the outdoor unit 21 is connected to the indoor unit 27a,
When it is relatively higher than 27b, 27c, and 27d, the gas refrigerant flows downward, and when it is below (upward flow).
Since the pressure loss in the connecting pipe becomes smaller than the influence of gravity, the correction can be performed by providing the set value (b) of the height difference switch 51, and the pressure loss can be calculated in consideration of gravity, so that the accuracy is further improved.

【００５８】次に、算出した圧損(△Ｐ)と吐出圧力(Ｐ
ｄ）を補正飽和温度算出器３８に入力した後について
は、実施の形態１と同様であるので、ここでは説明は省
略する。 こうすることにより、接続配管の長さに応じ
て圧損が増加することに対して、配管長範囲スイッチの
設定値による補正を加えることにより、また、室外ユニ
ット２１と室内ユニット２７ａ，２７ｂ，２７ｃ，２７
ｄの相対的な位置関係に対しては、高低差スイッチ５１
による補正を加えることにより、圧力損失（△Ｐ）の精
度が向上し、各室内熱交換器２９ａ，２９ｂ，２９ｃ，
２９ｄの真値に近い圧力を算出することが可能となるの
で、過冷却度を正確に補正して算出することができ、ど
のような運転周波数、配管接続、室外ユニット位置にお
いても設定した過冷却度に制御することができ高効率な
運転が可能となるものである。Next, the calculated pressure loss (ΔP) and discharge pressure (P
Since the process after inputting d) to the corrected saturation temperature calculator 38 is the same as that in the first embodiment, the description thereof is omitted here. By doing so, the pressure loss increases in accordance with the length of the connecting pipe, and the correction by the set value of the pipe length range switch is added, and the outdoor unit 21 and the indoor units 27a, 27b, 27c, 27
For the relative positional relationship of d, the height difference switch 51
The accuracy of the pressure loss (ΔP) is improved by adding the correction by, and each indoor heat exchanger 29a, 29b, 29c,
Since the pressure close to the true value of 29d can be calculated, the degree of supercooling can be accurately corrected and calculated, and the set subcooling can be obtained at any operating frequency, pipe connection, and outdoor unit position. It can be controlled every time and highly efficient operation is possible.

【００５９】なお、ここでも同様に、用いた圧損算出器
３７による圧力損失(△Ｐ)は運転周波数(ｆ)の１次の関
数としてのみならず、高次の式や一定値も本発明に含ま
れることは言うまでもない。Here, similarly, the pressure loss (ΔP) by the used pressure loss calculator 37 is not only a linear function of the operating frequency (f), but also higher-order equations and constant values are applicable to the present invention. Needless to say, it is included.

【００６０】また、配管長範囲スイッチ５０の設定値
（ａ）や高低差スイッチ５１の設定値（ｂ）は、本実施
の形態のような設定値のみならず、さらに詳細な分割な
ども可能であり、これらも本発明に含まれるものであ
る。Further, the set value (a) of the pipe length range switch 50 and the set value (b) of the height difference switch 51 are not limited to the set values as in the present embodiment, and more detailed divisions are possible. Yes, these are also included in the present invention.

【００６１】さらにまた、本実施の形態では冷媒の種類
については何も述べていないが、空調用で主流のＨＣＦ
Ｃ２２や、ＨＦＣ冷媒、ＨＦＣ混合冷媒においても、そ
の効果は全く同じものであり、これらも本発明に含まれ
るものである。Furthermore, although no mention is made of the type of the refrigerant in this embodiment, the mainstream HCF for air conditioning is used.
The effects are the same for C22, HFC refrigerant, and HFC mixed refrigerant, and these are also included in the present invention.

【００６２】一方、冷房運転時については、本発明の主
眼ではないので説明は省略する。On the other hand, the description of the cooling operation is omitted because it is not the main purpose of the present invention.

【００６３】（実施の形態３)図３は本発明の請求項５
および６記載の空気調和機の一実施の形態であり、冷凍
サイクルの回路図の概略を示しており、特に本発明の主
眼となる暖房運転時を中心に説明する。(Embodiment 3) FIG. 3 shows claim 5 of the present invention.
2 is an embodiment of the air conditioner described in (4) and (6), and shows a schematic circuit diagram of a refrigerating cycle. Particularly, a description will be given focusing on a heating operation which is the main object of the present invention.

【００６４】また、図１に示した実施の形態１と構成、
作用が同様のものについては同一番号で記し、詳細な説
明は省略する。The configuration of the first embodiment shown in FIG.
The same operation is denoted by the same reference numeral, and the detailed description is omitted.

【００６５】ここにおいては、接続配管（液管３１及び
ガス管３２）の配管長に応じて、設定値（ｃ）を入力す
ることができる配管長設定スイッチ６０および室外ユニ
ット２１と前記室内ユニット２７ａ，２７ｂ，２７ｃ，
２７ｄとの相対的な位置関係に応じて設定値（ｄ）を設
定することのできる高低差スイッチ６１をそれぞれ室外
ユニット２１に備えている。Here, the pipe length setting switch 60, the outdoor unit 21 and the indoor unit 27a, which can input the set value (c) according to the pipe length of the connecting pipes (the liquid pipe 31 and the gas pipe 32). , 27b, 27c,
Each outdoor unit 21 is provided with a height difference switch 61 capable of setting a set value (d) according to a relative positional relationship with 27d.

【００６６】本実施の形態においては、これらの設定値
はたとえば次表のようにする。In the present embodiment, these set values are set as shown in the following table.

【００６７】[0067]

【表２】 これらの設定値（ｃ），（ｄ）を、吐出圧力センサー３
４からの吐出圧力(Ｐｄ)データおよび周波数センサー３
６で検知した圧縮機の運転周波数(ｆ)データと共に圧損
算出器３７に送り、圧縮機２２から室内熱交換器２９
ａ，２９ｂ，２９ｃ，２９ｄの間の圧力損失(△Ｐ)をた
とえば次式のように算出する。[Table 2] These set values (c) and (d) are measured by the discharge pressure sensor 3
Discharge pressure (Pd) data from 4 and frequency sensor 3
The operating frequency (f) data of the compressor detected in 6 is sent to the pressure loss calculator 37, and the compressor 22 sends the indoor heat exchanger 29.
The pressure loss (ΔP) between a, 29b, 29c and 29d is calculated, for example, by the following equation.

【００６８】[0068]

【数５】△Ｐ＝ｃ×（Ａ×(ｆ)＋Ｂ）＋ｄ
Ａ，Ｂは定数 すなわち、ここでも圧損は配管長が長くなるほど大きく
なることは明白であり、このように配管長によって補正
できるような設定値（ｃ）を設け、圧損と略比例した関
係を持たせることにより、圧損の精度がさらにまた向上
する。[Expression 5] ΔP = c × (A × (f) + B) + d
A and B are constants, that is, it is clear that the pressure loss increases as the pipe length becomes longer. Therefore, the set value (c) that can be corrected by the pipe length is provided, and the pressure loss has a relationship substantially proportional to the pressure loss. By doing so, the accuracy of pressure loss is further improved.

【００６９】また、暖房運転時のガス管３２の冷媒流れ
を考えると、室外ユニット２１が室内ユニット２７ａ，
２７ｂ，２７ｃ，２７ｄより相対的に上にある場合には
ガス冷媒が下向きに流れ、下にある場合（上向き流れ）
よりも重力の影響で接続配管中の圧損は小さくなるた
め、高低差スイッチ５１の設定値（ｂ）を設けて補正を
加えることにより、重力も考慮した圧損を算出できるの
で精度がさらに向上する。Considering the refrigerant flow in the gas pipe 32 during the heating operation, the outdoor unit 21 is connected to the indoor unit 27a,
When it is relatively higher than 27b, 27c, and 27d, the gas refrigerant flows downward, and when it is below (upward flow).
Since the pressure loss in the connecting pipe becomes smaller than the influence of gravity, the correction can be performed by providing the set value (b) of the height difference switch 51, and the pressure loss can be calculated in consideration of gravity, so that the accuracy is further improved.

【００７０】次に、算出した圧損(△Ｐ)と吐出圧力(Ｐ
ｄ）を補正飽和温度算出器３８に入力した後について
は、実施の形態１と同様であるので、ここでは説明は省
略する。 こうすることにより、接続配管の長さに応じ
て圧損が増加することに対して、配管長そのものを入力
することのできる配管長スイッチの設定値による補正を
加えることにより、圧力損失（△Ｐ）の精度が向上し、
各室内熱交換器２９ａ，２９ｂ，２９ｃ，２９ｄの真値
に近い圧力を算出することが可能となるので、過冷却度
を正確に補正して算出することができ、どのような運転
周波数、配管接続においても設定した過冷却度に制御す
ることができ高効率な運転が可能となるものである。Next, the calculated pressure loss (ΔP) and discharge pressure (P
Since the process after inputting d) to the corrected saturation temperature calculator 38 is the same as that in the first embodiment, the description thereof is omitted here. By doing so, the pressure loss increases according to the length of the connecting pipe, but the pressure loss (ΔP) is corrected by adding the correction by the set value of the pipe length switch that can input the pipe length itself. The accuracy of
Since it becomes possible to calculate the pressure close to the true value of each indoor heat exchanger 29a, 29b, 29c, 29d, the degree of subcooling can be accurately corrected and calculated. Even in connection, the degree of supercooling can be controlled and the highly efficient operation becomes possible.

【００７１】なお、ここでも同様に、用いた圧損算出器
３７による圧力損失(△Ｐ)は運転周波数(ｆ)の１次の関
数としてのみならず、高次の式や一定値も本発明に含ま
れることは言うまでもない。Here, similarly, the pressure loss (ΔP) by the pressure loss calculator 37 used is not only a linear function of the operating frequency (f), but also higher-order equations and constant values are used in the present invention. Needless to say, it is included.

【００７２】また、配管長スイッチ６０の設定値（ｃ）
や高低差スイッチ６１の設定値（ｄ）は、本実施の形態
のような設定値のみならず、さらに詳細な分割なども可
能であり、これらも本発明に含まれるものである。The set value of the pipe length switch 60 (c)
The set value (d) of the height difference switch 61 is not limited to the set value as in the present embodiment, and more detailed division is possible, and these are also included in the present invention.

【００７３】さらにまた、本実施の形態では冷媒の種類
については何も述べていないが、空調用で主流のＨＣＦ
Ｃ２２や、ＨＦＣ冷媒、ＨＦＣ混合冷媒においても、そ
の効果は全く同じものであり、これらも本発明に含まれ
るものである。Furthermore, although no mention is made of the type of refrigerant in this embodiment, the mainstream HCF for air conditioning is used.
The effects are the same for C22, HFC refrigerant, and HFC mixed refrigerant, and these are also included in the present invention.

【００７４】一方、冷房運転時については、本発明の主
眼ではないので説明は省略する。On the other hand, the description of the cooling operation is omitted because it is not the main purpose of the present invention.

【００７５】[0075]

【発明の効果】以上述べたところから明らかなように、
請求項１および２記載の空気調和機によれば、吐出圧力
の値から室内熱交換器の圧力を正確に推定することが可
能となるので、過冷却度を補正して精度良く算出するこ
とができ、どのような運転周波数の状態においても設定
した過冷却度に室内膨張弁を制御することができ、常に
高効率な運転が可能となる。As is apparent from the above description,
According to the air conditioner of the first and second aspects, it is possible to accurately estimate the pressure of the indoor heat exchanger from the value of the discharge pressure. Therefore, the subcooling degree can be corrected and accurately calculated. It is possible to control the indoor expansion valve to the set degree of supercooling in any operating frequency state, and it is possible to always operate with high efficiency.

【００７６】また請求項３および４記載の空気調和機に
よれば、接続配管の長さに応じて圧損が増加することに
対して、配管長範囲スイッチの設定値による補正を加え
ることにより、圧力損失（△Ｐ）の精度が向上し、各室
内熱交換器の真値に近い圧力を算出することが可能とな
るので、過冷却度を正確に補正して算出することがで
き、どのような、運転周波数、配管接続においても設定
した過冷却度に室内膨張弁を制御することができ高効率
な運転が可能となるものである。Further, according to the air conditioner of the third and fourth aspects, the pressure loss increases according to the length of the connecting pipe, and the pressure is increased by the correction by the set value of the pipe length range switch. Since the accuracy of the loss (ΔP) is improved and the pressure close to the true value of each indoor heat exchanger can be calculated, the degree of supercooling can be accurately corrected and calculated. In addition, the indoor expansion valve can be controlled to the set supercooling degree even in the operating frequency and the pipe connection, and highly efficient operation can be performed.

【００７７】また、室外ユニットと室内ユニットとの相
対的な位置関係に応じて設定値を設定することのできる
高低差スイッチを設け、前記圧損算出手段は前記運転周
波数検知手段で検知した運転周波数の値と前記配管長範
囲スイッチの設定値と前記高低差スイッチの設定値を用
いて前記圧縮機近傍から前記室内熱交換器近傍の間の圧
損を算出するようにすることにより、さらに圧力損失
（△Ｐ）の精度が向上し、設定した過冷却度に室内膨張
弁を正確に制御することができ高効率な運転が可能とな
るものである。Further, a height difference switch capable of setting a set value in accordance with the relative positional relationship between the outdoor unit and the indoor unit is provided, and the pressure loss calculating means is provided with the operating frequency detected by the operating frequency detecting means. By calculating the pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger using the value, the setting value of the pipe length range switch, and the setting value of the height difference switch, the pressure loss (Δ The accuracy of P) is improved, the indoor expansion valve can be accurately controlled to the set degree of supercooling, and highly efficient operation becomes possible.

【００７８】また請求項５および６記載の空気調和機に
よれば、接続配管の長さに応じて圧損が増加することに
対して、配管長そのものを入力することのできる配管長
スイッチの設定値による補正を加えることにより、圧力
損失（△Ｐ）の精度が向上し、各室内熱交換器の真値に
近い圧力を算出することが可能となるので、過冷却度を
正確に補正して算出することができ、どのような運転周
波数、配管接続においても設定した過冷却度に制御する
ことができ高効率な運転が可能となるものである。According to the air conditioner of the fifth and sixth aspects, the set value of the pipe length switch capable of inputting the pipe length itself against the increase of the pressure loss according to the length of the connecting pipe. Since the accuracy of pressure loss (ΔP) is improved and the pressure close to the true value of each indoor heat exchanger can be calculated, the degree of supercooling is accurately corrected and calculated. Therefore, it is possible to control to a set degree of supercooling at any operating frequency and pipe connection, which enables highly efficient operation.

【００７９】また、この場合にも、高低差スイッチを設
けることにより、さらに圧力損失（△Ｐ）の精度が向上
し、設定した過冷却度に室内膨張弁を正確に制御するこ
とができ高効率な運転が可能となるものである。Also in this case, by providing the height difference switch, the accuracy of the pressure loss (ΔP) is further improved, and the indoor expansion valve can be accurately controlled to the set degree of supercooling, and high efficiency can be achieved. It is possible to perform various driving.

【図面の簡単な説明】[Brief description of drawings]

【図１】本発明の第１実施の形態に係わる空気調和機の
概略構成を示す図である。FIG. 1 is a diagram showing a schematic configuration of an air conditioner according to a first embodiment of the present invention.

【図２】本発明の第２実施の形態に係わる空気調和機の
概略構成を示す図である。FIG. 2 is a diagram showing a schematic configuration of an air conditioner according to a second embodiment of the present invention.

【図３】本発明の第３実施の形態に係わる空気調和機の
概略構成を示す図である。FIG. 3 is a diagram showing a schematic configuration of an air conditioner according to a third embodiment of the present invention.

【図４】従来の多室型空気調和機の概略構成を示す図で
ある。FIG. 4 is a diagram showing a schematic configuration of a conventional multi-room air conditioner.

【符号の説明】[Explanation of symbols]

２１ 室外ユニット ２２ 圧縮機 ２３ 四方弁 ２４ 室外熱交換器 ２５ 室外膨張弁 ２６ 室外ファン ２７ａ，２７ｂ，２７ｃ，２７ｄ 室内ユニット逆止弁 ２８ａ，２８ｂ，２８ｃ，２８ｄ 室内膨張弁 ２９ａ，２９ｂ，２９ｃ，２９ｄ 室内熱交換器 ３０ａ，３０ｂ，３０ｃ，３０ｄ 室内ファン ３１ 液管 ３２ ガス管 ３３ 冷媒回路 ３４ 吐出圧力センサー ３５ａ，３５ｂ，３５ｃ，３５ｄ 温度センサー ３６ 周波数センサーである。 ３７ 圧損算出器 ３８ 補正飽和温度算出器 ３９ 補正過冷却度算出器 ４０ 膨張弁制御器 ５０ 配管長範囲スイッチ ５１，６１ 高低差スイッチ ６０ 配管長設定スイッチ 21 outdoor unit 22 compressor 23 four-way valve 24 outdoor heat exchanger 25 outdoor expansion valve 26 outdoor fan 27a, 27b, 27c, 27d indoor unit check valve 28a, 28b, 28c, 28d indoor expansion valve 29a, 29b, 29c, 29d Indoor heat exchanger 30a, 30b, 30c, 30d Indoor fan 31 Liquid pipe 32 Gas pipe 33 Refrigerant circuit 34 Discharge pressure sensor 35a, 35b, 35c, 35d Temperature sensor 36 Frequency sensor 36. 37 Pressure loss calculator 38 Corrected saturation temperature calculator 39 Corrected supercooling degree calculator 40 Expansion valve controller 50 Pipe length range switch 51, 61 Height difference switch 60 Pipe length setting switch

───────────────────────────────────────────────────── フロントページの続き (72)発明者 北山 浩 大阪府東大阪市高井田本通４丁目２番５号 松下冷機株式会社内 (72)発明者 高谷 隆幸 大阪府東大阪市高井田本通４丁目２番５号 松下冷機株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Kitayama 4-2-5 Takada Hondori, Higashi-Osaka City, Osaka Prefecture Matsushita Refrigerator Co., Ltd. (72) Inventor Takayuki Takaya 4-chome Takaidamoto-dori, Higashi Osaka No. 2-5 Matsushita Cold Machinery Co., Ltd.

Claims (6)

【特許請求の範囲】[Claims] 【請求項１】少なくとも圧縮機、四方弁、室外熱交換
器、室外膨張弁を構成要素とする室外ユニットと、少な
くとも室内熱交換器、室内膨張弁を構成要素とする１台
以上の室内ユニットと、それら室外ユニットと室内ユニ
ットを接続する接続配管と、前記圧縮機の吐出圧力を検
出する吐出圧力検知手段と、前記室内熱交換器の液冷媒
温度を検出する液冷媒温度検出手段と、前記圧縮機近傍
から前記室内熱交換器近傍の間の冷媒圧損を算出する圧
損算出手段と、前記吐出圧力から前記圧損を減じた圧力
相当の飽和温度を算出する補正飽和温度算出手段と、前
記補正飽和温度算出手段で算出した飽和温度から前記液
冷媒温度検出手段で検出される温度を減じた値を前記室
内熱交出口過冷却度として算出する補正過冷却度算出手
段と、前記過冷却度が実質上一定の範囲の値となるよう
に前記室内膨張弁開度を制御する膨張弁制御器とを備え
たことを特徴とする空気調和機。1. An outdoor unit having at least a compressor, a four-way valve, an outdoor heat exchanger, and an outdoor expansion valve as constituent elements, and at least one indoor unit having at least an indoor heat exchanger and indoor expansion valve as constituent elements. A connection pipe connecting the outdoor unit and the indoor unit, discharge pressure detection means for detecting the discharge pressure of the compressor, liquid refrigerant temperature detection means for detecting the liquid refrigerant temperature of the indoor heat exchanger, and the compression A pressure loss calculating means for calculating a refrigerant pressure loss between the vicinity of the machine and the indoor heat exchanger, a correction saturation temperature calculating means for calculating a saturation temperature corresponding to a pressure obtained by subtracting the pressure loss from the discharge pressure, and the correction saturation temperature. Corrected supercooling degree calculating means for calculating a value obtained by subtracting the temperature detected by the liquid refrigerant temperature detecting means from the saturation temperature calculated by the calculating means as the indoor heat exchange outlet supercooling degree, and the supercooling degree An air conditioner characterized by comprising an expander valve controller for controlling the indoor expansion valve to a value substantially constant range. 【請求項２】前記圧縮機の運転周波数を検知する運転周
波数検知手段を備え、前記圧損算出手段は、前記運転周
波数の値を用いて前記圧縮機近傍から前記室内熱交換器
近傍の間の冷媒圧損を算出することを特徴とする請求項
１記載の空気調和機。2. An operating frequency detecting means for detecting an operating frequency of the compressor, wherein the pressure loss calculating means uses the value of the operating frequency to provide a refrigerant between the vicinity of the compressor and the vicinity of the indoor heat exchanger. The air conditioner according to claim 1, wherein the pressure loss is calculated. 【請求項３】少なくとも圧縮機、四方弁、室外熱交換
器、室外膨張弁を構成要素とする室外ユニットと、少な
くとも室内熱交換器、室内膨張弁を構成要素とする１台
以上の室内ユニットと、それら室外ユニットと室内ユニ
ットを接続する接続配管と、前記接続配管の配管長範囲
に応じて設定値を段階的に切り換えることができる配管
長範囲スイッチと、前記圧縮機の吐出圧力を検出する吐
出圧力検知手段と、前記圧縮機の運転周波数を検知する
運転周波数検知手段と、前記室内熱交換器の液冷媒温度
を検出する液冷媒温度検出手段と、前記運転周波数の値
と前記配管長範囲スイッチの設定値を用いて前記圧縮機
近傍から前記室内熱交換器近傍の間の冷媒圧損を算出す
る圧損算出手段と、前記吐出圧力から前記圧損を減じた
圧力相当の飽和温度を算出する補正飽和温度算出手段
と、前記補正飽和温度算出手段で算出した飽和温度から
前記液冷媒温度検出手段で検出される温度を減じた値を
前記室内熱交出口過冷却度として算出する補正過冷却度
算出手段と、前記過冷却度が略一定の範囲の値となるよ
うに前記室内膨張弁開度を制御する膨張弁制御器とを備
えたことを特徴とする空気調和機。3. An outdoor unit having at least a compressor, a four-way valve, an outdoor heat exchanger and an outdoor expansion valve as constituent elements, and at least one indoor unit having at least an indoor heat exchanger and indoor expansion valve as constituent elements. A connection pipe connecting the outdoor unit and the indoor unit, a pipe length range switch capable of stepwise switching a set value according to a pipe length range of the connection pipe, and a discharge detecting a discharge pressure of the compressor. Pressure detecting means, operating frequency detecting means for detecting the operating frequency of the compressor, liquid refrigerant temperature detecting means for detecting the liquid refrigerant temperature of the indoor heat exchanger, value of the operating frequency and the pipe length range switch A pressure loss calculating means for calculating a refrigerant pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger using a set value of, and a saturation temperature equivalent to a pressure obtained by subtracting the pressure loss from the discharge pressure. A correction saturation temperature calculating means for calculating, and a correction temperature for calculating a value obtained by subtracting the temperature detected by the liquid refrigerant temperature detecting means from the saturation temperature calculated by the correction saturation temperature calculating means as the indoor heat exchange outlet supercooling degree. An air conditioner comprising: a cooling degree calculating means; and an expansion valve controller that controls the opening degree of the indoor expansion valve so that the supercooling degree has a value in a substantially constant range. 【請求項４】前記室外ユニットと前記室内ユニットとの
相対的な位置関係に応じて設定値を設定することのでき
る高低差スイッチをさらに備え、前記圧損算出手段は前
記運転周波数検知手段で検知した運転周波数の値と前記
配管長範囲スイッチの設定値と前記高低差スイッチの設
定値を用いて前記圧縮機近傍から前記室内熱交換器近傍
の間の圧損を算出することを特徴とする請求項３記載の
空気調和機。4. A height difference switch capable of setting a set value in accordance with a relative positional relationship between the outdoor unit and the indoor unit, wherein the pressure loss calculating means detects the operating frequency detecting means. The pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger is calculated using the value of the operating frequency, the set value of the pipe length range switch, and the set value of the height difference switch. Air conditioner described. 【請求項５】少なくとも圧縮機、四方弁、室外熱交換
器、室外膨張弁を構成要素とする室外ユニットと、少な
くとも室内熱交換器、室内膨張弁を構成要素とする１台
以上の室内ユニットと、それら室外ユニットと室内ユニ
ットを接続する接続配管と、前記接続配管の配管長に応
じて設定値を設定することができる配管長設定スイッチ
と、前記圧縮機の吐出圧力を検出する吐出圧力検知手段
と、前記圧縮機の運転周波数を検知する運転周波数検知
手段と、前記室内熱交換器の液冷媒温度を検出する液冷
媒温度検出手段と、前記運転周波数の値と前記配管長設
定スイッチの設定値を用いて前記圧縮機近傍から前記室
内熱交換器近傍の間の冷媒圧損を算出する圧損算出手段
と、前記吐出圧力から前記圧損を減じた圧力相当の飽和
温度を算出する補正飽和温度算出手段と、前記補正飽和
温度算出手段で算出した飽和温度から前記液冷媒温度検
出手段で検出される温度を減じた値を前記室内熱交出口
過冷却度として算出する補正過冷却度算出手段と、前記
過冷却度が実質上一定の範囲の値となるように前記室内
膨張弁開度を制御する膨張弁制御器とを備えたことを特
徴とする空気調和機。5. An outdoor unit having at least a compressor, a four-way valve, an outdoor heat exchanger and an outdoor expansion valve as constituent elements, and at least one indoor unit having at least an indoor heat exchanger and indoor expansion valve as constituent elements. A connection pipe connecting the outdoor unit and the indoor unit, a pipe length setting switch capable of setting a set value according to the pipe length of the connection pipe, and a discharge pressure detection means for detecting the discharge pressure of the compressor. An operating frequency detecting means for detecting an operating frequency of the compressor, a liquid refrigerant temperature detecting means for detecting a liquid refrigerant temperature of the indoor heat exchanger, a value of the operating frequency and a setting value of the pipe length setting switch. Using a pressure loss calculating means for calculating a refrigerant pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger, and a correction for calculating a saturation temperature corresponding to the pressure obtained by subtracting the pressure loss from the discharge pressure. Corrected supercooling degree calculation for calculating a value obtained by subtracting the temperature detected by the liquid refrigerant temperature detection means from the saturation temperature calculated by the sum temperature calculation means and the corrected saturation temperature calculation means as the indoor heat exchange outlet supercooling degree An air conditioner comprising: a means and an expansion valve controller that controls the opening degree of the indoor expansion valve such that the degree of subcooling is a value in a substantially constant range. 【請求項６】前記室外ユニットと前記室内ユニットとの
相対的な位置関係に応じて設定値を設定することのでき
る高低差スイッチをさらに備え、前記圧損算出手段は前
記運転周波数検知手段で検知した運転周波数の値と前記
配管長設定スイッチの設定値と前記高低差スイッチの設
定値を用いて前記圧縮機近傍から前記室内熱交換器近傍
の間の圧損を算出することを特徴とする請求項５記載の
空気調和機。6. A height difference switch capable of setting a set value in accordance with a relative positional relationship between the outdoor unit and the indoor unit, wherein the pressure loss calculating means is detected by the operating frequency detecting means. The pressure loss between the vicinity of the compressor and the vicinity of the indoor heat exchanger is calculated using the value of the operating frequency, the setting value of the pipe length setting switch, and the setting value of the height difference switch. Air conditioner described.