JP3189492B2 - Operation control device for air conditioner - Google Patents
Operation control device for air conditionerInfo
- Publication number
- JP3189492B2 JP3189492B2 JP12898293A JP12898293A JP3189492B2 JP 3189492 B2 JP3189492 B2 JP 3189492B2 JP 12898293 A JP12898293 A JP 12898293A JP 12898293 A JP12898293 A JP 12898293A JP 3189492 B2 JP3189492 B2 JP 3189492B2
- Authority
- JP
- Japan
- Prior art keywords
- temperature
- expansion valve
- liquid
- refrigerant
- control
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
- F25B2313/005—Outdoor unit expansion valves
Landscapes
- Compression-Type Refrigeration Machines With Reversible Cycles (AREA)
- Air Conditioning Control Device (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、空気調和装置の運転制
御装置に関し、特に、膨脹弁の制御対策に係るものであ
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation control device for an air conditioner, and more particularly to a control measure for an expansion valve.
【０００２】[0002]
【従来の技術】従来より、空気調和装置には、特公平３
−４９０３４号公報に開示されているように、圧縮機と
四路切換弁と室外熱交換器と室外電動膨張弁と室内電動
膨張弁と室内熱交換器とが順に接続されて主冷媒回路が
形成されている。そして、冷暖房運転等の起動時におい
ては、各電動膨張弁の初期値を予め記憶している開度に
設定し、この初期開度に所定時間保持した後、各電動膨
張弁を過熱度及び過冷却度に応じて通常制御するように
している。2. Description of the Related Art Conventionally, air conditioners have
As disclosed in JP-A-49034, a main refrigerant circuit is formed by sequentially connecting a compressor, a four-way switching valve, an outdoor heat exchanger, an outdoor electric expansion valve, an indoor electric expansion valve, and an indoor heat exchanger. Have been. Then, at the time of starting the cooling / heating operation or the like, the initial value of each electric expansion valve is set to a previously stored opening degree, and after maintaining the initial opening degree for a predetermined time, each electric expansion valve is superheated and superheated. Normal control is performed according to the degree of cooling.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、上述し
た空気調和装置の運転制御装置においては、上記電動膨
張弁の初期開度の記憶データを安定運転時の開度に書換
え可能にしているものゝ、所定時間は一定の初期開度に
固定しているので、通常制御に移行するまで時間を要す
るという問題があった。つまり、冷房運転時及び暖房運
転時において、所定時間が経過するまで過熱度等に拘り
なく初期開度に室内電動膨張弁を保持するので、必要以
上に過熱度が大きくなり、室内熱交換器の能力を充分に
発揮させることができないという問題があった。また、
冷房運転時において、起動時より室内電動膨張弁を過熱
度制御すると、起動時では過熱度が生じないので、室内
電動膨張弁を閉鎖方向にのみ制御することになる。一
方、暖房運転時においても、起動時より室内電動膨張弁
を過冷却制御すると、この起動時では低圧の垂下により
圧縮機の運転周波数が低くなり、高低差圧が小さくなっ
て冷媒が流れ難く、しかも、室内熱交換器の液冷媒温度
が室内温度とほゞ等しくなり、過冷却度が小さいとして
室内電動膨張弁を絞るという問題がある。However, in the operation control device for an air conditioner described above, the stored data of the initial opening of the electric expansion valve can be rewritten to the opening during stable operation. Since the predetermined time is fixed at a constant initial opening, there is a problem that it takes time to shift to normal control. That is, during the cooling operation and the heating operation, the indoor electric expansion valve is held at the initial opening degree regardless of the degree of superheat until the predetermined time elapses, so that the degree of superheat is increased more than necessary, and There is a problem that the ability cannot be fully exhibited. Also,
If the degree of superheat of the indoor electric expansion valve is controlled during the cooling operation from the start, the degree of superheat does not occur at the start, so that the indoor electric expansion valve is controlled only in the closing direction. On the other hand, even during the heating operation, if the indoor electric expansion valve is supercooled from the start, the operating frequency of the compressor becomes low due to the low pressure droop at the start, the differential pressure becomes low, and the refrigerant is difficult to flow, Moreover, there is a problem that the temperature of the liquid refrigerant in the indoor heat exchanger becomes almost equal to the indoor temperature, and the degree of subcooling is small, so that the indoor electric expansion valve is throttled.
【０００４】本発明は、斯かる点に鑑みてなされたもの
であって、一定の冷媒流量を確保しつゝ通常制御への移
行を迅速にし、熱交換器能力を充分に利用できるように
することを目的とするものである。SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and ensures a constant refrigerant flow rate, speeds up the transition to normal control, and makes full use of the heat exchanger capacity. The purpose is to do so.
【０００５】[0005]
【課題を解決するための手段】上記の目的を達成するた
めに、本発明が講じた手段は、圧縮機の吸込側及び吐出
側の圧力相当飽和温度に基づいて膨張弁の開度を制御す
るようにしたものである。具体的に、図１に示すよう
に、請求項１に係る発明が講じた手段は、先ず、圧縮機
(21)と、熱源側熱交換器(24)と、開度調整可能な膨張弁
(32)と、利用側熱交換器(31)とが順に接続されて閉回路
の主冷媒回路(11)が形成されている空気調和装置の運転
制御装置を対象としている。そして、上記利用側熱交換
器(31)における吸込側液冷媒温度及び出口側ガス冷媒温
度をそれぞれ検出する液温検出手段(Th2) 及びガス温検
出手段(Th3) が設けらると共に、上記圧縮機(21)の吸込
側における低圧圧力相当飽和温度を検出する飽和温度検
出手段(51)が設けられている。更に、上記主冷媒回路(1
1)の配管長に基づく圧力損失によって定まる所定温度を
飽和温度検出手段(51)が検出した低圧圧力相当飽和温度
に加算した算出液冷媒温度と上記液温検出手段(Th2) の
検出液冷媒温度とを比較して低い温度を制御液温として
出力する液温出力手段(52)が設けられている。加えて、
該液温出力手段(52)が出力する制御液温とガス温検出手
段(Th3) が検出したガス冷媒温度とに基づく過熱度が所
定値になるように冷房運転時における上記膨張弁(32)の
開度を制御する開度制御手段(53)が設けられた構成とし
ている。Means for Solving the Problems In order to achieve the above-mentioned object, a means adopted by the present invention is to control the opening degree of an expansion valve based on a saturation temperature corresponding to a pressure on a suction side and a discharge side of a compressor. It is like that. Specifically, as shown in FIG. 1, means taken by the invention according to claim 1 is firstly a compressor.
(21), heat source side heat exchanger (24), expansion valve with adjustable opening
(32) and an operation control device of an air conditioner in which a use side heat exchanger (31) is sequentially connected to form a closed circuit main refrigerant circuit (11). Then, a liquid temperature detecting means (Th2) and a gas temperature detecting means (Th3) for respectively detecting the suction side liquid refrigerant temperature and the outlet side gas refrigerant temperature in the use side heat exchanger (31) are provided, and the compression A saturation temperature detecting means (51) for detecting a saturation temperature corresponding to a low pressure on the suction side of the machine (21) is provided. Further, the main refrigerant circuit (1
The calculated liquid refrigerant temperature obtained by adding the predetermined temperature determined by the pressure loss based on the pipe length of 1) to the saturated temperature corresponding to the low pressure detected by the saturated temperature detecting means (51), and the detected liquid refrigerant temperature of the liquid temperature detecting means (Th2) And a liquid temperature output means (52) for outputting a lower temperature as the control liquid temperature as compared with the control liquid temperature. in addition,
The expansion valve (32) during the cooling operation so that the superheat degree based on the control liquid temperature output from the liquid temperature output means (52) and the gas refrigerant temperature detected by the gas temperature detection means (Th3) becomes a predetermined value. The opening degree control means (53) for controlling the opening degree is provided.
【０００６】また、請求項２に係る発明が講じた手段
は、図２に示すように、先ず、圧縮機(21)と、熱源側熱
交換器(24)と、熱源側膨張機構(25)と、開度調整可能な
利用側膨張弁(32)と、利用側熱交換器(31)とが順に接続
されて閉回路の主冷媒回路(11)が形成されている空気調
和装置の運転制御装置を対象としている。そして、暖房
運転時の利用側熱交換器(31)における冷媒の過冷却度が
所定値になるように利用側膨張弁(32)の開度を制御する
過冷却制御手段(55)が設けられている。更に、上記主冷
媒回路(11)における高圧圧力相当飽和温度と利用側空気
温度との差温を判別する差温判別手段(56)が設けられて
いる。加えて、該差温判別手段(56)が判別した差温が所
定値以上になるまで暖房運転時における上記過冷却制御
手段(55)の制御を停止して利用側膨張弁(32)を所定開度
に保持する開度保持手段(57)が設けられた構成としてい
る。As shown in FIG. 2, the means taken by the invention according to claim 2 first includes a compressor (21), a heat source side heat exchanger (24), and a heat source side expansion mechanism (25). Operation control of an air conditioner in which a use-side expansion valve (32) whose opening is adjustable and a use-side heat exchanger (31) are sequentially connected to form a closed-circuit main refrigerant circuit (11). It is intended for equipment. Then, a supercooling control means (55) is provided for controlling the opening degree of the usage-side expansion valve (32) such that the degree of supercooling of the refrigerant in the usage-side heat exchanger (31) during the heating operation becomes a predetermined value. ing. Further, there is provided a temperature difference determining means (56) for determining the temperature difference between the saturated temperature corresponding to the high pressure and the use side air temperature in the main refrigerant circuit (11). In addition, the control of the supercooling control means (55) during the heating operation is stopped and the use-side expansion valve (32) is set to the predetermined temperature until the temperature difference determined by the temperature difference determination means (56) becomes equal to or more than a predetermined value. The opening degree holding means (57) for holding the opening degree is provided.
【０００７】[0007]
【作用】上記の構成により、請求項１記載の発明では、
先ず、液温検出手段(Th2) 及びガス温検出手段(Th3) が
利用側熱交換器(31)における吸込側液冷媒温度及び出口
側ガス冷媒温度をそれぞれ検出する一方、飽和温度検出
手段(51)が圧縮機(21)の吸込側における低圧圧力相当飽
和温度を検出している。そして、液温出力手段(52)は、
主冷媒回路(11)の配管長に基づく圧力損失によって定ま
る所定温度を飽和温度検出手段(51)が検出した低圧圧力
相当飽和温度に加算した算出液冷媒温度と上記液温検出
手段(Th2) の検出液冷媒温度とを比較して低い温度を制
御液温として出力する。つまり、例えば、低圧圧力相当
飽和温度に20℃を加算した温度を算出液冷媒温度とし、
この液冷媒温度と実際の液冷媒温度とを比較して低い方
の温度を制御液温とする。その後、上記液温出力手段(5
2)が出力する制御液温とガス温検出手段(Th3) が検出し
たガス冷媒温度とに基づく過熱度が所定値になるように
開度制御手段(53)が冷房運転時における上記膨張弁(32)
の開度を制御することになる。つまり、冷房運転の起動
時等において、膨張弁(32)を所定開度開くようにしてい
る。According to the above-mentioned structure, according to the first aspect of the present invention,
First, the liquid temperature detecting means (Th2) and the gas temperature detecting means (Th3) detect the suction side liquid refrigerant temperature and the outlet side gas refrigerant temperature in the use side heat exchanger (31), respectively, while the saturation temperature detecting means (51 ) Detects the low temperature equivalent temperature at the suction side of the compressor (21). And the liquid temperature output means (52)
The calculated liquid refrigerant temperature obtained by adding a predetermined temperature determined by the pressure loss based on the pipe length of the main refrigerant circuit (11) to the low-pressure-pressure equivalent saturated temperature detected by the saturated temperature detecting means (51) and the liquid temperature detecting means (Th2) A temperature lower than the detected liquid refrigerant temperature is output as a control liquid temperature. That is, for example, the temperature obtained by adding 20 ° C. to the low pressure pressure equivalent saturation temperature is set as the calculated liquid refrigerant temperature,
The liquid refrigerant temperature is compared with the actual liquid refrigerant temperature, and the lower temperature is set as the control liquid temperature. Then, the liquid temperature output means (5
The degree of superheat based on the control liquid temperature output by (2) and the gas refrigerant temperature detected by the gas temperature detection means (Th3) becomes a predetermined value so that the opening degree control means (53) performs the expansion valve (C) during the cooling operation. 32)
Will be controlled. That is, when the cooling operation is started, the expansion valve (32) is opened by a predetermined opening.
【０００８】また、請求項２に係る発明では、過冷却制
御手段(55)が、暖房運転時の利用側熱交換器(31)におけ
る冷媒の過冷却度が所定値になるように利用側膨張弁(3
2)の開度を制御していおり、例えば、利用側の液冷媒温
度と高圧圧力相当飽和温度とより利用側膨張弁(32)の開
度を過冷却制御することになる。一方、差温判別手段(5
6)は高圧圧力相当飽和温度と利用側空気温度、例えば、
室内温度との差温を判別している。そして、開度保持手
段(57)は、差温判別手段(56)が判別した差温が所定値以
上になるまで、例えば、高圧圧力相当飽和温度が室内温
度より５℃以上に上昇するまで暖房運転時における上記
過冷却制御手段(55)の制御を停止して利用側膨張弁(32)
を所定開度に保持し、起動時等における利用側膨張弁(3
2)の開度を保証するようにしている。Further, in the invention according to claim 2, the supercooling control means (55) controls the usage-side expansion so that the degree of supercooling of the refrigerant in the usage-side heat exchanger (31) during the heating operation becomes a predetermined value. Valve (3
The opening degree of 2) is controlled. For example, the opening degree of the usage-side expansion valve (32) is supercooled based on the usage-side liquid refrigerant temperature and the high-pressure equivalent temperature. On the other hand, the differential temperature determining means (5
6) is the high pressure equivalent temperature and the use side air temperature, for example,
The difference from the room temperature is determined. Then, the opening holding means (57) heats until the differential temperature determined by the differential temperature determining means (56) becomes equal to or higher than a predetermined value, for example, until the high temperature equivalent temperature rises to 5 ° C or more from the room temperature. During the operation, the control of the supercooling control means (55) is stopped and the utilization side expansion valve (32) is stopped.
Is maintained at a predetermined opening, and the usage-side expansion valve (3
The opening of 2) is guaranteed.
【０００９】[0009]
【発明の効果】従って、請求項１に係る発明によれば、
冷房運転の起動時において低圧圧力相当飽和温度に基づ
いて膨張弁(32)の開度を過熱度制御するようにしたゝめ
に、一定時間所定開度に保持する場合に比して通常制御
に移行する時間を短縮することができるので、熱交換器
能力を充分に発揮させることができることから、空調能
力の向上を図ることができる。また、長配管の小容量運
転時で且つ低外気冷房運転時において、起動時より膨張
弁(32)を過熱度制御する場合では、膨張弁(32)を絞る方
向に制御して低圧保護制御を行うことになるが、該膨張
弁(32)を所定開度に開くことができるので、低圧保護制
御の実行頻度を少なくすることができる。一方、請求項
２に係る発明によれば、暖房運転時においては、高圧圧
力相当飽和温度と利用側空気温度との差温が生じるまで
利用側膨張弁(32)を所定開度に保持するようにしたゝめ
に、冷房運転時と同様に一定時間所定開度に保持する場
合に比して通常制御に移行する時間を短縮することがで
きるので、熱交換器能力を充分に発揮させることができ
ることから、空調能力の向上を図ることができる。特
に、早朝時の暖房起動時において迅速に温度を上げるこ
とができるので、快適性の向上を図ることができる。ま
た、デフロスト運転後の暖房運転再開時において、利用
側膨張弁(32)を所定開度に開かせるので、フロストを生
じ難くすることができ、デフロスト運転の頻度を少なく
することができる。また、長配管で大容量接続時で且つ
低外気暖房運転時において、制御初期から利用側膨張弁
(32)を過冷却制御する場合では、膨張弁(32)が開かずに
システムが発散することになるが、該膨張弁(32)を所定
開度に開くので、システムの発散を確実に防止すること
ができる。Therefore, according to the first aspect of the present invention,
At the time of starting the cooling operation, the opening degree of the expansion valve (32) is controlled to be superheated based on the low pressure equivalent saturation temperature. Since the transition time can be shortened, the capacity of the heat exchanger can be sufficiently exhibited, and the air conditioning capacity can be improved. In addition, in the case of controlling the expansion valve (32) to a degree of superheating from the time of startup during the small capacity operation of the long piping and the low outside air cooling operation, the expansion valve (32) is controlled in the direction of being throttled to perform the low pressure protection control. However, since the expansion valve (32) can be opened to a predetermined opening, the execution frequency of the low pressure protection control can be reduced. On the other hand, according to the second aspect of the invention, during the heating operation, the use-side expansion valve (32) is maintained at the predetermined opening degree until a temperature difference between the high pressure equivalent saturation temperature and the use-side air temperature occurs. In addition, the time required to shift to the normal control can be shortened as compared with the case where the opening degree is maintained at a predetermined time for a certain period of time, as in the cooling operation, so that the heat exchanger capacity can be sufficiently exhibited. As a result, the air conditioning capacity can be improved. In particular, since the temperature can be quickly raised when heating is started in the early morning, comfort can be improved. In addition, when the heating operation is restarted after the defrost operation, the use-side expansion valve (32) is opened to a predetermined opening, so that frost can be hardly generated, and the frequency of the defrost operation can be reduced. In addition, when the large capacity is connected with the long piping and the low outside air heating operation is performed, the use-side expansion valve is used from the beginning of the control.
In the case of supercooling control of (32), the system diverges without opening the expansion valve (32) .However, since the expansion valve (32) is opened to a predetermined opening, the divergence of the system is reliably prevented. can do.
【００１０】[0010]
【実施例】以下、本発明の実施例について図面に基づい
て詳細に説明する。図３は、本発明に係る空気調和装置
(1) における室外ユニット(2) 及び室内ユニット(3) の
冷媒配管系統を示している。該室外ユニット(2) は、出
力周波数を３０〜１１６Hzの範囲で４〜１０Hz毎に可変
に切換えられるインバータ(2a)により運転容量が調整さ
れる圧縮機(21)と、該圧縮機(21)から吐出されるガス冷
媒中の油を分離する油分離器(22)と、冷房運転時には図
中実線の如く切換わり暖房運転時には図中破線の如く切
換わる四路切換弁(23)と、冷房運転時に凝縮器、暖房運
転時に蒸発器となる熱源側熱交換器としての室外熱交換
器(24)及び該室外熱交換器(24)に付設された室外ファン
(2F)と、暖房運転時に冷媒の絞り作用を行う熱源側膨張
機構である室外電動膨張弁(25)と、液化した冷媒を貯蔵
するレシーバ(26)と、アキュムレータ(27)とが主要機器
として内蔵されていて、上記圧縮機(21)及び室外熱交換
器(24)等の各機器はそれぞれ冷媒配管(4) で冷媒の流通
可能に接続されている。また、上記室内ユニット(3)
は、冷房運転時には蒸発器、暖房運転時には凝縮器とな
る利用側熱交換器としての室内熱交換器(31)及び該室内
熱交換器(31)に付設された室内ファン(3F)を備え、該室
内熱交換器(31)に接続された冷媒配管(4)の液管側に
は、暖房運転時に冷媒流量を調節し、冷房運転時に冷媒
の絞り作用を行う室内電動膨張弁(32)が設けられてい
る。そして、上記室外ユニット(2) 及び室内ユニット
(3) は、冷媒配管(4) である連絡配管(41)によって接続
され、上記圧縮機(21)、室外熱交換器(24)及び室内熱交
換器(31)等の各機器はそれぞれ冷媒配管(4) によって閉
回路に接続されて、室外空気との熱交換により得た熱を
室内空気に放出するようにした主冷媒回路(11)が構成さ
れている。Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 3 is an air conditioner according to the present invention.
2 shows a refrigerant piping system of the outdoor unit (2) and the indoor unit (3) in (1). The outdoor unit (2) includes a compressor (21) whose operating capacity is adjusted by an inverter (2a) whose output frequency is variably switched in a range of 30 to 116 Hz every 4 to 10 Hz, and a compressor (21). An oil separator (22) for separating oil in the gas refrigerant discharged from the chiller, a four-way switching valve (23) that switches as shown by the solid line in the drawing during cooling operation, and switches as shown by a broken line in the heating operation, and cooling. An outdoor heat exchanger (24) as a heat source side heat exchanger that becomes a condenser during operation and an evaporator during heating operation, and an outdoor fan attached to the outdoor heat exchanger (24)
(2F), an outdoor electric expansion valve (25) that is a heat source side expansion mechanism that performs a throttling action of the refrigerant during the heating operation, a receiver (26) that stores liquefied refrigerant, and an accumulator (27) as main devices. Each device, such as the compressor (21) and the outdoor heat exchanger (24), is built in and connected to the refrigerant pipe (4) so that the refrigerant can flow therethrough. In addition, the indoor unit (3)
An evaporator during cooling operation, an indoor heat exchanger (31) as a use-side heat exchanger serving as a condenser during heating operation, and an indoor fan (3F) attached to the indoor heat exchanger (31), On the liquid pipe side of the refrigerant pipe (4) connected to the indoor heat exchanger (31), an indoor electric expansion valve (32) that adjusts the refrigerant flow rate during the heating operation and performs a throttle function of the refrigerant during the cooling operation is provided. Is provided. Then, the outdoor unit (2) and the indoor unit
(3) is connected by a communication pipe (41) which is a refrigerant pipe (4), and each device such as the compressor (21), the outdoor heat exchanger (24), and the indoor heat exchanger (31) is a refrigerant pipe. A main refrigerant circuit (11) is connected to the closed circuit by the pipe (4) and discharges heat obtained by heat exchange with outdoor air to indoor air.
【００１１】また、(42)は、室外熱交換器(24)をバイパ
スする暖房過負荷制御用バイパス路であって、該バイパ
ス路(42)には、室外熱交換器(24)と共通の空気通路に設
置された補助熱交換器(4a)と、キャピラリチューブ(4b)
と、冷媒の高圧時に開作動する補助開閉弁(4c)とが順次
直列に且つ室外熱交換器(24)に対して並列に接続されて
いる。そして、上記暖房過負荷制御用バイパス路(42)
は、冷房運転時には常時、暖房運転時には高圧の過上昇
時に、上記補助開閉弁(4c)がオンして開状態になり、吐
出ガスの一部を主冷媒回路(11)から暖房過負荷制御用バ
イパス路(42)にバイパスし、吐出ガスの一部を補助熱交
換器(4a)で凝縮させるようにしている。(43)は、冷暖房
運転時に圧縮機(21)の吸入側に液冷媒を注入し吸入ガス
の過熱度を調節するためのリキッドインジェクションバ
イパス路であって、圧縮機(21)の吐出管温度の過上昇時
に開かれるインジェクション弁(4d)と、キャピラリチュ
ーブ(4e)とが介設されている。(44)は、キャピラリチュ
ーブ(4f)を介して上記油分離器(22)から圧縮機(21)に潤
滑油を戻すための油戻し管である。(45)は、圧縮機(21)
の吐出側冷媒配管(4) と吸入側冷媒配管(4) とを接続す
る均圧ホットガスバイパス路であって、サーモオフ状態
等による圧縮機(21)の停止時及び再起動前に一定時間だ
け開作動する均圧弁(4g)及びキャピラリチューブ(4h)が
介設されている。(46)は、上記レシーバ(26)と均圧ホッ
トガスバイパス路(45)との間に接続された均圧路であっ
て、一端はレシーバ(26)の上端面に、他端が上記均圧ホ
ットガスバイパス路(45)の均圧弁(4g)の上流側に接続さ
れている。この均圧路(46)は、レシーバ(26)から均圧ホ
ットガスバイパス路(45)へ向う冷媒流通のみを許容する
逆止弁(4i)が介設され、均圧弁(4g)が開放された状態
で、レシーバ(26)内の上層部のガス冷媒が均圧ホットガ
スバイパス路(45)、つまり、液冷媒が導入されることな
しに圧縮機(21)の吸入側に導入可能にしている。また、
(2b)は、圧縮機(21)の吸入側の吸入冷媒と冷媒配管(4)
の液管中の液冷媒との熱交換により吸入冷媒を冷却させ
て、連絡配管(41)における冷媒の過熱度の上昇を補償す
るための吸入管熱交換器である。A heating overload control bypass path (42) bypasses the outdoor heat exchanger (24). The bypass path (42) has a common path with the outdoor heat exchanger (24). Auxiliary heat exchanger (4a) installed in air passage and capillary tube (4b)
And an auxiliary on-off valve (4c) that is opened when the refrigerant is at a high pressure, are connected in series and in parallel to the outdoor heat exchanger (24). And the heating overload control bypass path (42)
The auxiliary on-off valve (4c) is turned on when the cooling operation is performed, and when the high pressure is excessively increased during the heating operation, a part of the discharge gas is supplied from the main refrigerant circuit (11) for heating overload control. The gas is bypassed to the bypass passage (42), and a part of the discharged gas is condensed by the auxiliary heat exchanger (4a). (43) is a liquid injection bypass for injecting a liquid refrigerant into the suction side of the compressor (21) during the cooling and heating operation to adjust the degree of superheat of the suction gas, and is a liquid injection bypass of the compressor (21). An injection valve (4d) that is opened at the time of excessive rise and a capillary tube (4e) are interposed. (44) is an oil return pipe for returning lubricating oil from the oil separator (22) to the compressor (21) via the capillary tube (4f). (45) Compressor (21)
A pressure equalizing hot gas bypass connecting the discharge side refrigerant pipe (4) and the suction side refrigerant pipe (4) of the compressor (21) due to a thermo-off state, etc. An open pressure equalizing valve (4g) and a capillary tube (4h) are interposed. (46) is a pressure equalizing path connected between the receiver (26) and the pressure equalizing hot gas bypass path (45), one end of which is on the upper end face of the receiver (26) and the other end of which is the equalizing path. The pressure hot gas bypass passage (45) is connected to the upstream side of the pressure equalizing valve (4g). The equalizing path (46) is provided with a check valve (4i) that allows only refrigerant flow from the receiver (26) to the equalizing hot gas bypass path (45), and the equalizing valve (4g) is opened. In this state, the gas refrigerant in the upper layer in the receiver (26) can be introduced into the suction side of the compressor (21) without introducing the equalizing hot gas bypass passage (45), that is, the liquid refrigerant. I have. Also,
(2b) is a refrigerant refrigerant and refrigerant pipe (4) on the suction side of the compressor (21).
This is a suction pipe heat exchanger for cooling the suction refrigerant by heat exchange with the liquid refrigerant in the liquid pipe to compensate for an increase in the degree of superheat of the refrigerant in the communication pipe (41).
【００１２】また、上記空気調和装置(1) には、多くの
センサ類が配置されていて、 (Th1)は、室内の吸込空気
温度である室内温度T1（利用側空気温度）を検出する室
温センサ、 (Th2)及び(Th3) は、それぞれ室内熱交換器
(31)の液側及びガス側冷媒配管(4) における液冷媒温度
T2及びガス冷媒温度T3を検出する液温検出手段及びガス
温検出手段である室内液温センサ及び室内ガス温セン
サ、 (Th4)は、圧縮機(21)の吐出管温度T4を検出する吐
出管センサ、 (Th5)は、室外熱交換器(24)の液冷媒温度
T5からデフロスト等を検出する室外液温センサ、 (Th6)
は、上記吸入管熱交換器(2b)の下流側の吸入冷媒配管
(4) に配置されて圧縮機(21)の吸入管温度T6を検出する
吸入管センサ、 (Th7)は、室外熱交換器(24)の空気吸込
口に配置されて室外の吸込空気温度である外気温度T7を
検出する外気温センサ、(P1)は、圧縮機(21)の吐出側に
配設されて主冷媒回路(11)の高圧側圧力を検出する高圧
センサ、(P2)は、圧縮機(21)の吸入側に配設されて主冷
媒回路(11)の低圧側圧力を検出する低圧センサ、 (HPS)
は、圧縮機(21)の吐出側に配設された圧縮機(21)の保護
用高圧圧力開閉器である。そして、上記各電動膨張弁(2
5, 32)及びセンサ(Th1〜Th7)等は、コントロールユニッ
ト(5) に信号線で接続され、該コントロールユニット
(5) は、各センサ(Th1〜Th7)等の検出信号を受けて各電
動膨張弁(25, 32)等の開閉制御や圧縮機(21)の容量制御
を行うようになっている。In the air conditioner (1), many sensors are arranged. (Th1) is a room temperature for detecting a room temperature T1 (use side air temperature) which is a room intake air temperature. Sensors (Th2) and (Th3) are indoor heat exchangers respectively
Liquid refrigerant temperature in liquid-side and gas-side refrigerant pipes (4) in (31)
An indoor liquid temperature sensor and an indoor gas temperature sensor which are liquid temperature detecting means and gas temperature detecting means for detecting T2 and gas refrigerant temperature T3, and (Th4) is a discharge pipe for detecting a discharge pipe temperature T4 of the compressor (21). Sensor, (Th5) is the liquid refrigerant temperature of the outdoor heat exchanger (24)
Outdoor liquid temperature sensor that detects defrost from T5, (Th6)
Is the suction refrigerant pipe on the downstream side of the suction pipe heat exchanger (2b).
(Th) is disposed at the air suction port of the outdoor heat exchanger (24) and detects the suction air temperature T6 of the outdoor heat exchanger (24). An outside air temperature sensor that detects a certain outside air temperature T7, (P1) is a high-pressure sensor that is disposed on the discharge side of the compressor (21) and detects the high-pressure side pressure of the main refrigerant circuit (11), and (P2) is A low pressure sensor disposed on the suction side of the compressor (21) to detect a low pressure side pressure of the main refrigerant circuit (11); (HPS)
Is a high-pressure switch for protection of the compressor (21) disposed on the discharge side of the compressor (21). Then, each of the electric expansion valves (2
5, 32) and sensors (Th1 to Th7) are connected to the control unit (5) by signal lines,
(5) receives the detection signals from the sensors (Th1 to Th7) and controls the opening and closing of the electric expansion valves (25, 32) and the capacity of the compressor (21).
【００１３】また、上記コントロールユニット(15)に
は、本発明の特徴として、冷房運転時における室内電動
膨張弁(32)を制御するための飽和温度検出手段(51)と液
温出力手段(52)と冷房開度制御手段(53)とが設けられる
と共に、暖房運転時における室外電動膨張弁(25)及び室
内電動膨張弁(32)を制御するための暖房開度制御手段(5
4)と過冷却制御手段(55)と差温判別手段(56)と開度保持
手段(57)とが設けられている。該飽和温度検出手段(51)
は、上記低圧センサ(P2)が検出した低圧側圧力より圧縮
機(21)の吸込側における低圧圧力相当飽和温度Teを検出
するように構成されている。上記液温出力手段(52)は、
主冷媒回路(11)の配管長に基づく圧力損失によって定ま
る所定温度を飽和温度検出手段(51)が検出した低圧圧力
相当飽和温度Teに加算した算出液冷媒温度TH2 と上記室
内液温センサ(Th2) が検出した検出液冷媒温度T2とを比
較して低い温度を制御液温として出力するように構成さ
れている。具体的に、上記液温出力手段(52)は、低圧圧
力相当飽和温度Teに20℃を加算して算出液冷媒温度TH2
(Te＋20）としており、この算出液冷媒温度TH2 は室内
熱交換器(31)における圧力相当飽和温度に対応し、この
算出液冷媒温度TH2 と検出液冷媒温度T2との低い方を制
御液温Th2Dとしている。上記冷房開度制御手段(53)は、
該液温出力手段(52)が出力する制御液温Th2Dと室内ガス
温センサ(Th3) が検出したガス冷媒温度T3とに基づく過
熱度SHが所定値になるように上記室内電動膨張弁(32)の
開度を制御するように構成されている。つまり、該開度
制御手段(53)は、通常制御においては、圧縮機(21)の吐
出管温度T4と高圧圧力相当飽和温度Tcとの吐出管過熱度
に基づいて室内熱交換器(31)における目標過熱度を設定
して湿り制御を行うようにしている。その際、低外気冷
房運転の起動時等において、上記室内液温センサ(Th2)
及び室内ガス温センサ(Th3) が検出する液冷媒温度T2及
びガス冷媒温度T3では、液冷媒温度T2が室内温度にほゞ
等しいので、過熱度SHが小さいと判断して室内電動膨張
弁(32)を絞る制御を行うことになる。そこで、上記圧縮
機(21)が起動すると、低圧側圧力は直後に低下すること
から、上記低圧圧力相当飽和温度Teに基づいて過熱度SH
を制御するようにしている。The control unit (15) includes, as features of the present invention, a saturation temperature detecting means (51) and a liquid temperature output means (52) for controlling the indoor electric expansion valve (32) during the cooling operation. ) And a cooling opening control means (53), and a heating opening control means (5) for controlling the outdoor electric expansion valve (25) and the indoor electric expansion valve (32) during the heating operation.
4), supercooling control means (55), differential temperature determination means (56), and opening degree holding means (57) are provided. The saturation temperature detecting means (51)
Is configured to detect a low pressure pressure equivalent saturation temperature Te on the suction side of the compressor (21) from the low pressure side pressure detected by the low pressure sensor (P2). The liquid temperature output means (52) is
The calculated liquid refrigerant temperature TH2 obtained by adding a predetermined temperature determined by the pressure loss based on the pipe length of the main refrigerant circuit (11) to the low-pressure-pressure equivalent saturated temperature Te detected by the saturated temperature detecting means (51) and the indoor liquid temperature sensor (Th2 ) Is configured to output a lower temperature as the control liquid temperature as compared with the detected liquid refrigerant temperature T2. Specifically, the liquid temperature output means (52) calculates the liquid refrigerant temperature TH2 by adding 20 ° C. to the low pressure pressure equivalent saturation temperature Te.
(Te + 20), and the calculated liquid refrigerant temperature TH2 corresponds to the pressure equivalent saturation temperature in the indoor heat exchanger (31), and the lower one of the calculated liquid refrigerant temperature TH2 and the detected liquid refrigerant temperature T2 is the control liquid temperature Th2D. And The cooling opening control means (53)
The indoor electric expansion valve (32) such that the degree of superheat SH based on the control liquid temperature Th2D output by the liquid temperature output means (52) and the gas refrigerant temperature T3 detected by the indoor gas temperature sensor (Th3) becomes a predetermined value. ) Is controlled. That is, in the normal control, the opening degree control means (53) controls the indoor heat exchanger (31) based on the discharge pipe superheat degree between the discharge pipe temperature T4 of the compressor (21) and the high-pressure equivalent temperature Tc. Is set to perform the wetness control. At that time, at the time of starting the low outside air cooling operation, etc., the indoor liquid temperature sensor (Th2)
At the liquid refrigerant temperature T2 and the gas refrigerant temperature T3 detected by the indoor gas temperature sensor (Th3), since the liquid refrigerant temperature T2 is almost equal to the indoor temperature, it is determined that the superheat degree SH is small, and the indoor electric expansion valve (32 ). Therefore, when the compressor (21) is started, the low pressure side pressure immediately decreases, so the superheat degree SH is determined based on the low pressure pressure equivalent saturation temperature Te.
To control.
【００１４】一方、上記暖房開度制御手段(54)は、吸入
管センサ(Th6) が検出する圧縮機(21)の吸入管温度T6と
飽和温度検出手段(51)が検出する低圧圧力相当飽和温度
Teとに基づく過熱度SH（T6−Te）が所定値になるように
上記室外電動膨張弁(25)の開度を制御するように構成さ
れている。上記過冷却制御手段(55)は、暖房運転時の室
内熱交換器(31)における冷媒の過冷却度が所定値になる
ように室内電動膨張弁(32)の開度を制御するように構成
されている。つまり、該過冷却制御手段(55)は、上記室
内液温センサ(Th2) が検出する液冷媒温度T2と高圧セン
サ(P1)が検出した高圧側圧力よる高圧圧力相当飽和温度
Tcとに基づく過冷却度（T2−Tc）が所定値になるように
室内電動膨張弁(32)の開度を制御している。上記差温判
別手段(56)は、高圧センサ(P1)の高圧側圧力よる高圧圧
力相当飽和温度Tcが室温センサ(Th1) の検出室内温度T1
より高くなった温度差である差温を判別するように構成
されている。つまり、停止時における室内側の液冷媒温
度T2は室内温度T1にほゞ等しくなっているので、高圧圧
力相当飽和温度Tcが室内温度T1より上昇すると、主冷媒
回路(11)における差圧が生じていると見做すことができ
ることから、上記差温判別手段(56)は、高圧圧力相当飽
和温度Tcと室内温度T1より差温を判別するようにしてい
る。上記開度保持手段(57)は、差温判別手段(56)の差温
信号に基づき高圧圧力相当飽和温度Tcが室内温度T1との
差温が所定値以上になるまで暖房運転時における上記過
冷却制御手段(55)の制御を停止して室内電動膨張弁(32)
を所定開度に保持するように構成されている。具体的
に、該開度保持手段(57)は、高圧圧力相当飽和温度Tcが
室内温度T1より５℃以上高くなるまで、室内電動膨張弁
(32)を全開の2000パルスに保持する。つまり、低外気暖
房運転の起動時や、油戻し運転後の暖房運転再開時や、
デフロスト運転後の暖房運転再開時等において、低圧の
垂下によって圧縮機(21)の運転周波数が低くなり、高低
差圧が小さくなって冷媒が流れ難く、しかも、室内の液
冷媒温度T2が室内温度T1にほゞ等しいので、過冷却度が
小さいと判断して室内電動膨張弁(32)を絞る制御を行う
ことになる。そこで、上記開度保持手段(57)は、高圧圧
力相当飽和温度Tcが高くなるまで、室内電動膨張弁(32)
を全開に保持し、その後、上記過冷却制御手段(55)が、
室内電動膨張弁(32)を全開状態から過冷却度が所定値に
なるように開度を制御する。On the other hand, the heating opening control means (54) is provided with a suction pipe temperature T6 of the compressor (21) detected by the suction pipe sensor (Th6) and a low pressure pressure equivalent saturation detected by the saturation temperature detection means (51). temperature
The opening degree of the outdoor electric expansion valve (25) is controlled so that the superheat degree SH (T6-Te) based on Te becomes a predetermined value. The supercooling control means (55) is configured to control the opening degree of the indoor electric expansion valve (32) so that the degree of supercooling of the refrigerant in the indoor heat exchanger (31) during the heating operation becomes a predetermined value. Have been. In other words, the supercooling control means (55) determines the saturation temperature corresponding to the high pressure based on the liquid refrigerant temperature T2 detected by the indoor liquid temperature sensor (Th2) and the high pressure side pressure detected by the high pressure sensor (P1).
The opening degree of the indoor electric expansion valve (32) is controlled such that the degree of subcooling (T2-Tc) based on Tc becomes a predetermined value. The above-mentioned differential temperature determining means (56) is configured such that the high-pressure-pressure equivalent saturation temperature Tc based on the high-pressure side pressure of the high-pressure sensor (P1) is equal to the detection room temperature T1
It is configured to determine a difference temperature that is a higher temperature difference. That is, since the indoor-side liquid refrigerant temperature T2 at the time of stoppage is almost equal to the indoor temperature T1, when the high-pressure equivalent temperature Tc rises above the indoor temperature T1, a differential pressure in the main refrigerant circuit (11) occurs. Therefore, the temperature difference determining means (56) determines the temperature difference from the high pressure equivalent temperature Tc and the room temperature T1. The opening holding means (57) is configured to perform the heating operation during the heating operation until the temperature difference between the high pressure equivalent saturation temperature Tc and the room temperature T1 becomes equal to or higher than a predetermined value based on the temperature difference signal from the temperature difference determination means (56). The control of the cooling control means (55) is stopped and the indoor electric expansion valve (32) is stopped.
Is maintained at a predetermined opening. More specifically, the opening degree holding means (57) operates the indoor electric expansion valve until the high-pressure equivalent temperature Tc becomes higher than the room temperature T1 by 5 ° C. or more.
(32) is held at 2000 pulses of full opening. In other words, when starting the low outside air heating operation, when restarting the heating operation after the oil return operation,
When the heating operation is resumed after the defrost operation, for example, the operating frequency of the compressor (21) is lowered due to the low pressure droop, the high / low differential pressure is reduced, and the refrigerant is less likely to flow, and the indoor liquid refrigerant temperature T2 is the indoor temperature. Since it is almost equal to T1, it is determined that the degree of subcooling is small, and control to throttle the indoor electric expansion valve (32) is performed. Therefore, the opening degree maintaining means (57) is operated until the high pressure equivalent saturation temperature Tc becomes high, and the indoor electric expansion valve (32)
Is held fully open, and then the supercooling control means (55)
The opening degree of the indoor electric expansion valve (32) is controlled so that the degree of supercooling becomes a predetermined value from the fully opened state.
【００１５】次に、上記空気調和装置(1) の運転動作に
ついて説明する。図３において、空気調和装置の冷房運
転時には、四路切換弁(23)が図中実線側に切換わり、補
助熱交換器(4a)の補助開閉弁(4c)が常に開いて、圧縮機
(21)で圧縮された冷媒が、室外熱交換器(24)及び補助熱
交換器(4a)で凝縮され、連絡配管(41)を経て室内ユニッ
ト(3) に送られる。そして、この室内ユニット(3) で
は、液冷媒が、室内電動膨張弁(32)で減圧され、室内熱
交換器(31)で蒸発した後、連絡配管(41)を経て室外ユニ
ット(2) にガス状態で戻り、圧縮機(21)に吸入されるよ
うに循環する。つまり、液冷媒が室内熱交換器(31)にお
いて室内空気との間で熱交換を行って蒸発することによ
り室内空気を冷却することになる。また、暖房運転時に
は、四路切換弁(23)が図中破線側に切換わり、冷媒の流
れは上記冷房運転時と逆となって、圧縮機(21)で圧縮さ
れた冷媒が、室内熱交換器(31)で凝縮され、液状態で室
外ユニット(2) に流れ、室外電動膨張弁(25)により減圧
され、室外熱交換器(24)で蒸発した後、圧縮機(21)に戻
るように循環する。つまり、ガス冷媒が室内熱交換器(3
1)において室内空気との間で熱交換を行って凝縮するこ
とにより室内空気を加熱することになる。Next, the operation of the air conditioner (1) will be described. In FIG. 3, during the cooling operation of the air conditioner, the four-way switching valve (23) is switched to the solid line side in the figure, and the auxiliary on-off valve (4c) of the auxiliary heat exchanger (4a) is always open, and the compressor
The refrigerant compressed in (21) is condensed in the outdoor heat exchanger (24) and the auxiliary heat exchanger (4a), and is sent to the indoor unit (3) via the communication pipe (41). In the indoor unit (3), the liquid refrigerant is decompressed by the indoor electric expansion valve (32), evaporated in the indoor heat exchanger (31), and then communicated to the outdoor unit (2) through the communication pipe (41). It returns in a gaseous state and circulates so as to be sucked into the compressor (21). That is, the liquid refrigerant cools the indoor air by performing heat exchange with the indoor air in the indoor heat exchanger (31) and evaporating. Further, during the heating operation, the four-way switching valve (23) is switched to the broken line side in the figure, and the flow of the refrigerant is opposite to that during the cooling operation, and the refrigerant compressed by the compressor (21) is cooled by the indoor heat. Condensed in the exchanger (31), flows in liquid state to the outdoor unit (2), is depressurized by the outdoor electric expansion valve (25), evaporates in the outdoor heat exchanger (24), and returns to the compressor (21) Circulate like so. That is, the gas refrigerant is supplied to the indoor heat exchanger (3
In 1), indoor air is heated by performing heat exchange with indoor air and condensing.
【００１６】そこで、上記空気調和装置(1) における室
内電動膨張弁(32)の開度制御について図４及び図５に基
づき説明する。図４は、冷房運転時における室内電動膨
張弁(32)の制御を示しており、室内電動膨張弁(32)の通
常制御を開始し、先ず、ステップST１において、室温セ
ンサ(Th1) が検出する室内温度T1の１分間の平均温度か
ら室温室内電動膨張弁(32)の制御定数Ａを設定した後、
ステップST２に移り、制御定数Ａから制御定数Ａの最低
値Aminを算出する。続いて、ステップST３に移り、室内
液温センサ(Th2) が検出した液冷媒温度T2が−５℃より
低いか否かを判定し、該液冷媒温度T2が−５℃より低い
場合には、ステップST３からステップST４に移り、目標
過熱度SHS を５に設定する一方、上記液冷媒温度T2が−
５℃より高い場合には、ステップST３からステップST５
に移り、目標過熱度SHS の決定モジュールを実行して目
標過熱度SHS を決定する。The control of the opening degree of the indoor electric expansion valve (32) in the air conditioner (1) will now be described with reference to FIGS. FIG. 4 shows the control of the indoor electric expansion valve (32) during the cooling operation. Normal control of the indoor electric expansion valve (32) is started. First, in step ST1, the room temperature sensor (Th1) detects the temperature. After setting the control constant A of the room temperature indoor electric expansion valve (32) from the one-minute average temperature of the room temperature T1,
The process proceeds to step ST2, where the minimum value Amin of the control constant A is calculated from the control constant A. Subsequently, the process proceeds to step ST3, where it is determined whether or not the liquid refrigerant temperature T2 detected by the indoor liquid temperature sensor (Th2) is lower than −5 ° C. If the liquid refrigerant temperature T2 is lower than −5 ° C. The process proceeds from step ST3 to step ST4, in which the target superheat degree SHS is set to 5, while the liquid refrigerant temperature T2 is-
If the temperature is higher than 5 ° C., steps ST3 to ST5
Then, the target superheat degree SHS determination module is executed to determine the target superheat degree SHS.
【００１７】その後、上記ステップST４及びステップST
５からステップST６に移り、室内液温センサ（Th2）が
検出した液冷媒温度T2が、低圧圧力相当飽和温度Teから
算出した算出液冷媒温度TH2より高いか否かを判定す
る。つまり、液温出力手段（52）は、低圧圧力相当飽和
温度Teに20℃を加算した算出液冷媒温度TH2が室内液温
センサ（Th2）が検出した実際の液冷媒温度T2より低い
か否かを判定する。そして、実際の液冷媒温度T2が低い
場合には、上記ステップST６からステップST７に移り、
上記室内液温センサ（Th2）が検出した液冷媒温度T2を
制御液温Th2Dとする。また、上記算出液冷媒温度TH2が
実際の液冷媒温度T2より低い場合には、上記ステップST
６からステップST８に移り、上記算出液冷媒温度TH2を
制御液温Th2Dとする。その後、上記ステップST７及びス
テップST８からステップST９に移り、上記液温出力手段
（52）が出力した制御液温Th2Dと、室内ガス温センサ
（Th3）が検出したガス冷媒温度T3とから過熱度SHを算
出すると共に、制御定数Ｂを３に設定する。続いて、ス
テップST10に移り、上記制御定数Ｂと目標過熱度SHSと
過熱度SHとより開度制御手段（53）が室内電動膨張弁
（32）の開度変化量を算出して開度を設定する。次い
で、ステップST11に移り、制御する室内電動膨張弁（3
2）の開度が、上記ステップST２で設定した制御定数Ａ
の最低値Aminより小さいか否かを判定し、制御開度が最
低値Aminより大きい場合には、そのまゝ制御開度で制御
してリターンする一方、制御開度が制御定数Ａの最低値
Aminより小さい場合には、上記ステップST11からステッ
プST12に移り、制御開度を最低値Aminに設定してリター
ンすることになる。つまり、室内熱交換器（31）におけ
る液冷媒温度T2が高い場合、圧力相当飽和温度に基づい
て室内電動膨張弁（32）を過熱度制御することになる。Thereafter, step ST4 and step ST4 are performed.
The process proceeds from step 5 to step ST6, and it is determined whether or not the liquid refrigerant temperature T2 detected by the indoor liquid temperature sensor (Th2) is higher than the calculated liquid refrigerant temperature TH2 calculated from the low-pressure-pressure equivalent temperature Te. That is, the liquid temperature output means (52) determines whether the calculated liquid refrigerant temperature TH2 obtained by adding 20 ° C. to the low pressure pressure equivalent saturation temperature Te is lower than the actual liquid refrigerant temperature T2 detected by the indoor liquid temperature sensor (Th2). Is determined. When the actual liquid refrigerant temperature T2 is low, the process proceeds from step ST6 to step ST7,
The liquid refrigerant temperature T2 detected by the indoor liquid temperature sensor (Th2) is defined as a control liquid temperature Th2D. If the calculated liquid refrigerant temperature TH2 is lower than the actual liquid refrigerant temperature T2,
The process proceeds from step 6 to step ST8 where the calculated liquid refrigerant temperature TH2 is set as a control liquid temperature Th2D. Thereafter, the process proceeds from step ST7 and step ST8 to step ST9, where the degree of superheat SH is determined from the control liquid temperature Th2D output by the liquid temperature output means (52) and the gas refrigerant temperature T3 detected by the indoor gas temperature sensor (Th3). Is calculated, and the control constant B is set to 3. Subsequently, the process proceeds to step ST10, where the opening control means (53) calculates the opening change amount of the indoor electric expansion valve (32) based on the control constant B, the target superheat degree SHS, and the superheat degree SH, and determines the opening degree. Set. Next, the process proceeds to step ST11 where the indoor electric expansion valve (3
The opening degree of 2) is the control constant A set in step ST2.
It is determined whether or not the control opening is smaller than the minimum value Amin. If the control opening is larger than the minimum value Amin, the control is returned at the control opening and the control opening is returned to the minimum value of the control constant A.
If smaller than Amin, the process proceeds from step ST11 to step ST12, the control opening is set to the minimum value Amin, and the routine returns. That is, when the liquid refrigerant temperature T2 in the indoor heat exchanger (31) is high, the degree of superheating of the indoor electric expansion valve (32) is controlled based on the pressure-equivalent saturation temperature.
【００１８】一方、図５は、暖房運転時における室内電
動膨張弁(32)の制御を示している。先ず、スタートして
ステップST21において、暖房運転時にサーモオンして圧
縮機(21)を駆動した後、ステップST22に移り、タイマを
スタートさせてステップST23に移り、室内電動膨張弁(3
2)の初期開度決定サブルーチンを実行して初期開度を決
定する。続いて、上記タイマがタイムアップすると、上
記ステップST23からステップST24に移り、高圧センサ(P
1)の検出高圧側圧力に基づく高圧圧力相当飽和温度Tcと
室温センサ(Th1) が検出した室内温度T1の１分間の平均
温度T1(AV)と比較し、高圧圧力相当飽和温度Tcが室内温
度T1の平均温度T1(AV)より５℃以上に高いか否かを判定
する。そして、該高圧圧力相当飽和温度Tcが室内温度T1
の平均温度T1(AV)より５℃以上に高い場合には、上記ス
テップST24からステップST25に移り、室内電動膨張弁(3
2)の通常開度決定サブルーチンを実行し、過冷却制御手
段(55)が室内の液冷媒温度T2と高圧圧力相当飽和温度Tc
とより室内電動膨張弁(32)の開度を過冷却制御すること
になる。一方、上記高圧圧力相当飽和温度Tcが室内温度
T1の平均温度T1(AV)より５℃より低い場合は、上記ステ
ップST24からステップST26に移り、開度保持手段(57)が
室内電動膨張弁(32)の開度を全開の2000パルスに保持
し、上記ステップST24に戻ることになる。つまり、高圧
圧力相当飽和温度Tcが上昇するまで、室内電動膨張弁(3
2)の開度を全開に保持し、その後、該高圧圧力相当飽和
温度Tcが上昇し、過冷却度が大きくなると、上記ステッ
プST24からステップST25に移り、過冷却制御手段(55)が
室内電動膨張弁(32)を全開状態から過冷却制御を行うこ
とになる。FIG. 5 shows the control of the indoor electric expansion valve (32) during the heating operation. First, in step ST21, after the thermostat is turned on during the heating operation to drive the compressor (21) in step ST21, the process proceeds to step ST22, a timer is started and the process proceeds to step ST23, and the indoor electric expansion valve (3
The initial opening determination subroutine of 2) is executed to determine the initial opening. Subsequently, when the timer expires, the process proceeds from step ST23 to step ST24, where the high-pressure sensor (P
The 1-minute average temperature T1 (AV) of the high-pressure-pressure equivalent saturation temperature Tc based on the detected high-side pressure and the room temperature T1 detected by the room temperature sensor (Th1) is compared with the room temperature T1 (AV). It is determined whether or not the temperature is higher than the average temperature T1 (AV) of T1 by 5 ° C. or more. The high temperature equivalent temperature Tc is equal to the room temperature T1.
If it is higher than the average temperature T1 (AV) by 5 ° C. or more, the process proceeds from step ST24 to step ST25, where the indoor electric expansion valve (3
The normal opening determination subroutine of 2) is executed, and the subcooling control means (55) sets the indoor liquid refrigerant temperature T2 and the high pressure equivalent temperature Tc.
Thus, the degree of opening of the indoor electric expansion valve (32) is supercooled. On the other hand, the high pressure equivalent saturation temperature Tc is the room temperature.
If the average temperature of T1 is lower than 5 ° C. than T1 (AV), the process proceeds from step ST24 to step ST26, where the opening degree holding means (57) holds the opening degree of the indoor electric expansion valve (32) at 2000 pulses of full opening. Then, the process returns to step ST24. That is, the indoor electric expansion valve (3
The opening degree of 2) is kept fully open, and thereafter, when the high temperature equivalent temperature Tc rises and the degree of supercooling increases, the process proceeds from step ST24 to step ST25, where the subcooling control means (55) The supercooling control is performed from the fully opened state of the expansion valve (32).
【００１９】従って、本実施例によれば、冷房運転の起
動時において低圧圧力相当飽和温度Teに基づいて室内電
動膨張弁(32)の開度を過熱度制御するようにしたゝめ
に、一定時間所定開度に保持する場合に比して通常制御
に移行する時間を短縮することができるので、熱交換器
能力を充分に発揮させることができることから、空調能
力の向上を図ることができる。また、長配管の小容量運
転時で且つ低外気冷房運転時において、起動時より室内
電動膨張弁(32)を過熱度制御する場合では、室内電動膨
張弁(32)を絞る方向に制御し、この結果、低圧保護制御
を行うことになるが、該室内電動膨張弁(32)を所定開度
に開くことができるので、低圧保護制御の実行頻度を少
なくすることができる。一方、暖房運転時においては、
高圧圧力相当飽和温度Tcと室内温度T1との差温が生じる
まで室内電動膨張弁(32)を所定開度に保持するようにし
たゝめに、上述した冷房運転時と同様に一定時間所定開
度に保持する場合に比して通常制御に移行する時間を短
縮することができるので、熱交換器能力を充分に発揮さ
せることができることから、空調能力の向上を図ること
ができる。特に、早朝時の暖房起動時において迅速に温
度を上げることができるので、快適性の向上を図ること
ができる。また、デフロスト運転後の暖房運転再開時に
おいて、室内電動膨張弁(32)を所定開度に開かせるの
で、フロストを生じ難くすることができ、デフロスト運
転の頻度を少なくすることができる。また、長配管で大
容量接続時で且つ低外気暖房運転時において、制御初期
から室内電動膨張弁(32)を過冷却制御する場合では、室
内電動膨張弁(32)が開かずにシステムが発散することに
なるが、該室内電動膨張弁(32)を所定開度に開くので、
システムの発散を確実に防止することができる。Therefore, according to the present embodiment, at the time of starting the cooling operation, the opening degree of the indoor electric expansion valve (32) is controlled to the degree of superheat based on the low pressure equivalent temperature Te. Since the time required to shift to the normal control can be shortened as compared with the case where the opening degree is maintained at the predetermined opening degree, the heat exchanger capacity can be sufficiently exhibited, and the air conditioning capacity can be improved. In addition, during the small capacity operation of the long pipe and during the low outdoor air cooling operation, when controlling the degree of superheat of the indoor electric expansion valve (32) from the start, the indoor electric expansion valve (32) is controlled in a direction to throttle, As a result, the low pressure protection control is performed. However, since the indoor electric expansion valve (32) can be opened to a predetermined opening, the execution frequency of the low pressure protection control can be reduced. On the other hand, during the heating operation,
The indoor electric expansion valve (32) is kept at a predetermined opening degree until a temperature difference between the high pressure equivalent temperature Tc and the indoor temperature T1 occurs. Since the time required to shift to the normal control can be shortened as compared with the case where the temperature is kept at a high level, the heat exchanger capacity can be sufficiently exhibited, and the air conditioning capacity can be improved. In particular, since the temperature can be quickly raised when heating is started in the early morning, comfort can be improved. Further, at the time of restarting the heating operation after the defrost operation, the indoor electric expansion valve (32) is opened to a predetermined opening, so that frost can be hardly generated, and the frequency of the defrost operation can be reduced. In addition, when the indoor electric expansion valve (32) is supercooled from the beginning of the control when the large capacity is connected with the long pipe and the low outside air heating operation is performed, the system diverges without opening the indoor electric expansion valve (32). However, since the indoor electric expansion valve (32) is opened to a predetermined opening degree,
Divergence of the system can be reliably prevented.
【００２０】尚、本実施例は、１台の室内ユニット(3)
を有する空気調和装置(1) について説明したが、本発明
は、複数台の室内ユニット(3,3, 〜 )を有するマルチ型
であってもよいことは勿論である。また、上記液温出力
手段(52)は、低圧圧力相当飽和温度Teに20℃を加算して
算出液冷媒温度TH2 としたが、該20℃は、配管長さに応
じて変更するようにしてもよい。また、上記差温判別手
段(56)は、高圧圧力相当飽和温度Tcと室内温度T1との差
温を判別するようにしたが、請求項２に係る発明では、
室内ユニット(3) における吸込空気温度（室内温度T1）
と吹出空気温度との差温を判別するようにしてもよく、
また、室内の液冷媒温度T2と高圧圧力相当飽和温度Tcと
の差温で差温を判別するようにしてもよい。つまり、上
記吹出空気温度は高圧圧力相当飽和温度Tcに対応し、ま
た、室内の液冷媒温度T2は、運転停止時においては室内
温度T1に対応しているからである。また、上記開度保持
手段(57)は、室内電動膨張弁(32)を全開意外の開度に保
持するようにしてもよいことは勿論である。In this embodiment, one indoor unit (3)
Although the air conditioner (1) having the above has been described, it goes without saying that the present invention may be a multi-type having a plurality of indoor units (3, 3,...). Further, the liquid temperature output means (52) calculates the liquid refrigerant temperature TH2 by adding 20 ° C. to the low pressure pressure equivalent saturation temperature Te, and the 20 ° C. is changed according to the pipe length. Is also good. Further, the temperature difference determining means (56) determines the temperature difference between the high temperature equivalent temperature Tc and the room temperature T1, but in the invention according to claim 2,
Suction air temperature in the indoor unit (3) (indoor temperature T1)
And the temperature difference between the air temperature and the outlet air temperature may be determined,
Further, the temperature difference may be determined based on the temperature difference between the indoor liquid refrigerant temperature T2 and the high pressure equivalent saturation temperature Tc. That is, the outlet air temperature corresponds to the high pressure equivalent temperature Tc, and the indoor liquid refrigerant temperature T2 corresponds to the indoor temperature T1 when the operation is stopped. Further, it is a matter of course that the opening holding means (57) may hold the indoor electric expansion valve (32) at an opening other than the full opening.
【図１】請求項１の発明の構成を示すブロック図であ
る。FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention.
【図２】請求項２の発明の構成を示すブロック図であ
る。FIG. 2 is a block diagram showing a configuration of the invention of claim 2;
【図３】空気調和装置の冷媒配管系統を示す冷媒回路図
である。FIG. 3 is a refrigerant circuit diagram showing a refrigerant piping system of the air conditioner.
【図４】冷房運転時の室内電動膨張弁の開度制御を示す
制御フロー図である。FIG. 4 is a control flowchart showing opening degree control of an indoor electric expansion valve during a cooling operation.
【図５】暖房運転時の室内電動膨張弁の開度制御を示す
制御フロー図である。FIG. 5 is a control flowchart showing opening degree control of an indoor electric expansion valve during a heating operation.
1 空気調和装置 11 主冷媒回路 2 室外ユニット 21 圧縮機 24 室外熱交換器（熱源側熱交換器） 25 室外電動膨張弁 3 室内ユニット 31 室内熱交換器（利用側熱交換器） 32 室内電動膨張弁 5 コントローラ 51 飽和温度検出手段 52 液温出力手段 53 冷房開度制御手段 54 暖房開度制御手段 55 過冷却制御手段 56 差温判別手段 57 開度保持手段 Th1 室温センサ Th2 室内液温センサ（液温検出手段） Th3 室内ガス温センサ（ガス温検出手段） 1 Air conditioner 11 Main refrigerant circuit 2 Outdoor unit 21 Compressor 24 Outdoor heat exchanger (heat source side heat exchanger) 25 Outdoor electric expansion valve 3 Indoor unit 31 Indoor heat exchanger (use side heat exchanger) 32 Indoor electric expansion Valve 5 Controller 51 Saturation temperature detecting means 52 Liquid temperature output means 53 Cooling opening control means 54 Heating opening control means 55 Subcooling control means 56 Differential temperature discriminating means 57 Opening holding means Th1 Room temperature sensor Th2 Indoor liquid temperature sensor (liquid Temperature detection means) Th3 Indoor gas temperature sensor (gas temperature detection means)
───────────────────────────────────────────────────── フロントページの続き (72)発明者 井上 博之 大阪府堺市金岡町1304番地 ダイキン工 業株式会社 堺製作所 金岡工場内 (56)参考文献 特開 平４−356648（ＪＰ，Ａ) 特開 平３−217767（ＪＰ，Ａ) 特開 昭60−185076（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) F24F 11/02 102 F25B 1/00 304 F25B 13/00 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroyuki Inoue 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries, Ltd. Sakai Works Kanaoka Factory (56) References JP-A-4-356648 (JP, A) JP Hei 3-217767 (JP, A) JP-A-60-185076 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) F24F 11/02 102 F25B 1/00 304 F25B 13/00
Claims (2)
開度調整可能な膨張弁(32)と、利用側熱交換器(31)とが
順に接続されて閉回路の主冷媒回路(11)が形成されてい
る空気調和装置の運転制御装置であって、 上記利用側熱交換器(31)における吸込側液冷媒温度及び
出口側ガス冷媒温度をそれぞれ検出する液温検出手段(T
h2) 及びガス温検出手段(Th3) と、 上記圧縮機(21)の吸込側における低圧圧力相当飽和温度
を検出する飽和温度検出手段(51)と、 上記主冷媒回路(11)の配管長に基づく圧力損失によって
定まる所定温度を飽和温度検出手段(51)が検出した低圧
圧力相当飽和温度に加算した算出液冷媒温度と上記液温
検出手段(Th2) の検出液冷媒温度とを比較して低い温度
を制御液温として出力する液温出力手段(52)と、 該液温出力手段(52)が出力する制御液温とガス温検出手
段(Th3) が検出したガス冷媒温度とに基づく過熱度が所
定値になるように冷房運転時における上記膨張弁(32)の
開度を制御する開度制御手段(53)とを備えていることを
特徴とする空気調和装置の運転制御装置。1. A compressor (21), a heat source side heat exchanger (24),
An operation control device for an air conditioner in which an opening-adjustable expansion valve (32) and a use-side heat exchanger (31) are sequentially connected to form a closed-circuit main refrigerant circuit (11). A liquid temperature detecting means (T) for detecting the suction side liquid refrigerant temperature and the outlet side gas refrigerant temperature in the utilization side heat exchanger (31), respectively.
h2) and gas temperature detecting means (Th3), a saturated temperature detecting means (51) for detecting a low pressure equivalent temperature on the suction side of the compressor (21), and a pipe length of the main refrigerant circuit (11). The calculated liquid refrigerant temperature obtained by adding the predetermined temperature determined by the pressure loss based on the saturated temperature detection means (51) to the low pressure equivalent saturation temperature detected by the saturation temperature detection means (51) is lower than the liquid refrigerant temperature detected by the liquid temperature detection means (Th2). Liquid temperature output means (52) for outputting a temperature as a control liquid temperature; and a degree of superheat based on the control liquid temperature output from the liquid temperature output means (52) and the gas refrigerant temperature detected by the gas temperature detection means (Th3). And an opening control means (53) for controlling the opening of the expansion valve (32) during the cooling operation so that the air temperature becomes a predetermined value.
熱源側膨張機構(25)と、開度調整可能な利用側膨張弁(3
2)と、利用側熱交換器(31)とが順に接続されて閉回路の
主冷媒回路(11)が形成されている空気調和装置の運転制
御装置であって、 暖房運転時の利用側熱交換器(31)における冷媒の過冷却
度が所定値になるように利用側膨張弁(32)の開度を制御
する過冷却制御手段(55)と、 上記主冷媒回路(11)における高圧圧力相当飽和温度と利
用側空気温度との差温を判別する差温判別手段(56)と、 上記差温判別手段(56)が判別した差温が所定値以上にな
るまで暖房運転時における上記過冷却制御手段(55)の制
御を停止して利用側膨張弁(32)を所定開度に保持する開
度保持手段(57)とを備えていることを特徴とする空気調
和装置の運転制御装置。2. A compressor (21), a heat source side heat exchanger (24),
The heat source side expansion mechanism (25) and the use side expansion valve (3
2) and the use side heat exchanger (31) are connected in order to form a closed circuit main refrigerant circuit (11), the operation control device of the air conditioner, wherein the use side heat during heating operation is provided. Supercooling control means (55) for controlling the degree of opening of the use-side expansion valve (32) so that the degree of supercooling of the refrigerant in the exchanger (31) becomes a predetermined value; and a high-pressure pressure in the main refrigerant circuit (11). A temperature difference determining means (56) for determining a temperature difference between the equivalent saturation temperature and the use side air temperature; and the temperature difference during the heating operation until the temperature difference determined by the temperature difference determining means (56) becomes a predetermined value or more. Opening control means (57) for stopping the control of the cooling control means (55) and holding the use-side expansion valve (32) at a predetermined opening degree; .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12898293A JP3189492B2 (en) | 1993-05-31 | 1993-05-31 | Operation control device for air conditioner |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12898293A JP3189492B2 (en) | 1993-05-31 | 1993-05-31 | Operation control device for air conditioner |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06341695A JPH06341695A (en) | 1994-12-13 |
| JP3189492B2 true JP3189492B2 (en) | 2001-07-16 |
Family
ID=14998201
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12898293A Expired - Fee Related JP3189492B2 (en) | 1993-05-31 | 1993-05-31 | Operation control device for air conditioner |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3189492B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101229345B1 (en) * | 2008-02-13 | 2013-02-05 | 삼성전자주식회사 | Controlling method of multi type air conditioning |
| JP2010249452A (en) * | 2009-04-17 | 2010-11-04 | Mitsubishi Electric Corp | Air conditioner |
| JP6485256B2 (en) * | 2015-07-01 | 2019-03-20 | 株式会社デンソー | Refrigeration cycle equipment |
| CN115013931B (en) * | 2022-05-16 | 2024-03-26 | 美的集团武汉暖通设备有限公司 | Air conditioner, control method and device thereof and computer readable storage medium |
-
1993
- 1993-05-31 JP JP12898293A patent/JP3189492B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06341695A (en) | 1994-12-13 |
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