JP2007155299A - Air conditioner - Google Patents

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JP2007155299A
JP2007155299A JP2005355187A JP2005355187A JP2007155299A JP 2007155299 A JP2007155299 A JP 2007155299A JP 2005355187 A JP2005355187 A JP 2005355187A JP 2005355187 A JP2005355187 A JP 2005355187A JP 2007155299 A JP2007155299 A JP 2007155299A
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temperature
heat exchanger
outdoor heat
compressor
outdoor
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Tetsuya Sato
哲也 佐藤
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Sharp Corp
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Sharp Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To eliminate unnecessary defrosting operation by accurately determining frosting even at the start of heating operation regardless of the length of a pipe. <P>SOLUTION: This air conditioner comprises a first temperature detector 9 detecting outdoor heat exchanger temperature Tc on the inlet side of an outdoor heat exchanger 6 in heating operation; a second temperature detector 10 detecting compressor intake pipe temperature Ts; and an outside air temperature detector 11 detecting outside air temperature To. A control device 6 determines frosting when each of the difference between the outside air temperature To and the outdoor heat exchanger temperature Tc and the difference between the outside air temperature To and the compressor intake pipe temperature Ts is larger than a predetermined value to perform defrosting operation. When either one of the differences is smaller than the predetermined value, non-frosting is determined, and no defrosting operation is performed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、室外熱交換器の着霜を検出して、除霜運転を行う空気調和機に関する。   The present invention relates to an air conditioner that detects frost formation in an outdoor heat exchanger and performs a defrosting operation.

冷凍サイクルが形成された空気調和機では、暖房運転時に蒸発器となる室外熱交換器の温度が低下すると、室外熱交換器の表面に空気中の水分が付着して氷結してしまう状態、いわゆる着霜状態となる。室外熱交換器に多量に着霜すると、暖房能力の低下を招く。適当な着霜の量の時点で、着霜の判定を行い、除霜運転を行う必要がある。除霜運転では、冷凍サイクルの冷媒の流れを暖房運転時とは逆にして、室外熱交換器に高温高圧のガス冷媒を着霜した室外熱交換器に流しこみ、霜を溶かすものである。   In an air conditioner in which a refrigeration cycle is formed, when the temperature of the outdoor heat exchanger that serves as an evaporator during heating operation decreases, moisture in the air adheres to the surface of the outdoor heat exchanger and freezes, so-called It becomes a frosting state. If a large amount of frost is formed on the outdoor heat exchanger, the heating capacity is reduced. When an appropriate amount of frost is formed, it is necessary to determine the frost and perform a defrosting operation. In the defrosting operation, the refrigerant flow in the refrigeration cycle is reversed from that in the heating operation, and the high-temperature and high-pressure gas refrigerant is poured into the outdoor heat exchanger to melt the frost.

着霜を検出するためには、室外熱交換器の温度を検出するとともに、室外温度を検出している。室外熱交換器の温度を検出する温度検出器は、暖房運転時における室外熱交換器の入口側に設けられる。室外熱交換器の温度が低下して、外気温との差が一定値以上になると、着霜と判定し、除霜運転が開始される。   In order to detect frost formation, the temperature of the outdoor heat exchanger is detected and the outdoor temperature is detected. The temperature detector that detects the temperature of the outdoor heat exchanger is provided on the inlet side of the outdoor heat exchanger during heating operation. When the temperature of the outdoor heat exchanger decreases and the difference from the outside air temperature becomes a certain value or more, it is determined that the frost is formed, and the defrosting operation is started.

ここで、急速暖房のように運転停止状態から圧縮機を一気に高回転で駆動する場合、冷凍サイクルにおける低圧側、すなわち室外熱交換器や圧縮機の吸入管の圧力は大きく低下する。このとき、室外熱交換器の入口側の温度は大きく低下する。外気温との差が一定値以上になると、制御装置は、着霜と判断し、除霜運転を開始する。そのため、室外熱交換器には着霜していないにもかかわらず、除霜運転が開始され、暖房運転が中断される。室内が暖かくなるまでの時間が長くなり、無駄にエネルギを消費してしまうことになる。   Here, when the compressor is driven at a high rotation speed from an operation stop state as in rapid heating, the pressure on the low pressure side in the refrigeration cycle, that is, the pressure of the outdoor heat exchanger or the suction pipe of the compressor is greatly reduced. At this time, the temperature on the inlet side of the outdoor heat exchanger greatly decreases. When the difference from the outside air temperature becomes equal to or greater than a certain value, the control device determines that frost formation has occurred and starts the defrosting operation. Therefore, although the outdoor heat exchanger is not frosted, the defrosting operation is started and the heating operation is interrupted. It takes a long time to warm the room, and wastes energy.

これに対し、特許文献１では、暖房運転開始後、除霜運転を行わない時間を設定し、この設定時間経過してから、着霜を検出すると、除霜運転を行う。これによって、暖房運転開始時に、上記のように誤って除霜運転してしまうことを防いでいる。
特開平１０−１０３８１８号公報 On the other hand, in patent document 1, after heating operation start, the time which does not perform defrost operation is set, and if this set time passes, if defrosting is detected, defrost operation will be performed. This prevents erroneous defrosting operation as described above at the start of heating operation.
JP-A-10-103818

上記のように設定時間待つことにより、室外熱交換器の入口側の温度は上昇するため、外気温との差が一定値より小さくなり、着霜の誤検知はなくなる。しかしながら、冷凍サイクルを構成する配管が長い場合、特に室内機から室外機までの配管が長い場合において、停止状態から圧縮機を起動したとき、または圧縮機が低回転から高回転運転になったとき、室外熱交換器の入口側の温度低下は大きくなる。そのため、設定時間経過後も、室外熱交換器の入口側の温度と外気温との差は一定値より大きい。制御装置は着霜と判定し、誤って除霜運転が開始される。あるいは、設定時間をさらに長くすると、長尺配管の場合における着霜の誤検知はなくなるが、正常な状態での着霜の検知が遅れてしまい、過剰の着霜状態になり、暖房能力の低下を招くことになる。   By waiting for the set time as described above, the temperature on the inlet side of the outdoor heat exchanger rises, so the difference from the outside air temperature becomes smaller than a certain value, and erroneous detection of frost formation is eliminated. However, when the piping constituting the refrigeration cycle is long, especially when the piping from the indoor unit to the outdoor unit is long, when the compressor is started from a stopped state, or when the compressor is changed from low rotation to high rotation The temperature drop on the inlet side of the outdoor heat exchanger becomes large. Therefore, even after the set time has elapsed, the difference between the temperature on the inlet side of the outdoor heat exchanger and the outside air temperature is greater than a certain value. The control device determines that the frost is formed, and the defrosting operation is erroneously started. Alternatively, if the set time is further increased, erroneous detection of frost formation in the case of long pipes will be eliminated, but detection of frost formation in a normal state will be delayed, resulting in excessive frost formation, and a reduction in heating capacity Will be invited.

本発明は、上記に鑑み、配管の長短に関係なく、暖房運転開始時または圧縮機が低回転から高回転運転にしたときにおいても、正確に着霜を判定することができる空気調和機の提供を目的とする。   In view of the above, the present invention provides an air conditioner that can accurately determine frost formation at the start of heating operation or when the compressor is switched from low rotation to high rotation regardless of the length of the piping. With the goal.

本発明は、圧縮機、室内熱交換器、膨張弁および室外熱交換器が配管により連結され、暖房運転中に室外熱交換器への着霜を検出して、除霜運転を行う制御装置と、前記室外熱交換器の入口側の温度を検出する第１温度検出器と、前記室外熱交換器の出口側の温度を検出する第２温度検出器と、室外温度を検出する外気温検出器とが設けられ、前記制御装置は、前記３つの温度に基づいて着霜を判定するものである。   The present invention relates to a control device in which a compressor, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger are connected by piping, detecting frost formation on the outdoor heat exchanger during heating operation, and performing a defrosting operation. A first temperature detector for detecting the temperature on the inlet side of the outdoor heat exchanger, a second temperature detector for detecting the temperature on the outlet side of the outdoor heat exchanger, and an outside air temperature detector for detecting the outdoor temperature And the control device determines frost formation based on the three temperatures.

すなわち、制御装置は、室外温度と室外熱交換器の入口側の温度との差および室外温度と室外熱交換器の出口側の温度との差がそれぞれ所定値より大きいとき、着霜と判定して、除霜運転を行う。いずれかの差が所定値より小、あるいは両方の差がそれぞれ所定値より小のとき、着霜していないと判定して、除霜運転は行わない。   That is, when the difference between the outdoor temperature and the temperature on the inlet side of the outdoor heat exchanger and the difference between the outdoor temperature and the temperature on the outlet side of the outdoor heat exchanger are each greater than a predetermined value, the control device determines that frost formation has occurred. The defrosting operation is performed. When one of the differences is smaller than the predetermined value or both of the differences are smaller than the predetermined value, it is determined that frosting has not occurred, and the defrosting operation is not performed.

暖房運転時において、室外熱交換器に着霜していないとき、もしくは微少な着霜状態では、冷媒は室外空気と十分な熱交換を行っているため、室外熱交換器全体、すなわち入口から出口までの温度と室外温度との差は所定値よりも小さい。室外熱交換器での着霜が進行すると、室外熱交換器での熱交換が十分に行われなくなり、室外熱交換器全体、すなわち入口から出口までの温度は低下し、室外温度との差は所定値よりも大きくなる。したがって、制御装置は、着霜と判定し、除霜運転を行う。   During heating operation, when the outdoor heat exchanger is not frosted or in a slight frosted state, the refrigerant is sufficiently exchanging heat with the outdoor air, so the entire outdoor heat exchanger, that is, the inlet to the outlet The difference between the temperature up to and the outdoor temperature is smaller than a predetermined value. When frost formation in the outdoor heat exchanger progresses, heat exchange in the outdoor heat exchanger is not sufficiently performed, the temperature of the entire outdoor heat exchanger, that is, the temperature from the inlet to the outlet decreases, and the difference from the outdoor temperature is It becomes larger than a predetermined value. Therefore, a control apparatus determines with frost formation and performs defrost operation.

また、運転停止状態から圧縮機を高周波数で駆動するような急速暖房を行ったとき、または圧縮機が低回転から高回転運転になったとき、室外熱交換器の入口側の温度は、大きく低下して、室外温度とのは所定値よりも大きくなる。しかし、室外熱交換器は着霜していないため、冷媒は室外空気と十分な熱交換を行っており、室外熱交換器の出口側の温度は低下せず、室外温度との差は所定値よりも大きくはならない。したがって、制御装置は、着霜していないと正しく判定し、除霜運転を行わない。   In addition, when rapid heating is performed such that the compressor is driven at a high frequency from the shutdown state, or when the compressor is switched from low rotation to high rotation, the temperature on the inlet side of the outdoor heat exchanger is large. It decreases and the outdoor temperature becomes larger than a predetermined value. However, since the outdoor heat exchanger is not frosted, the refrigerant sufficiently exchanges heat with the outdoor air, the temperature on the outlet side of the outdoor heat exchanger does not decrease, and the difference from the outdoor temperature is a predetermined value. No bigger than. Therefore, the control device correctly determines that frosting has not occurred and does not perform the defrosting operation.

第１温度検出器は、暖房運転時における室外熱交換器の入口近傍に設けられ、第２温度検出器は、暖房運転時に前記室外熱交換器の出口につながる圧縮機の吸入管に設けられる。圧縮機の吸入管の温度は、室外熱交換器の出口側の温度に相当する。第２温度検出器は、過熱度検出用として既存のものであり、着霜の検出に利用している。   The first temperature detector is provided in the vicinity of the inlet of the outdoor heat exchanger during heating operation, and the second temperature detector is provided in the suction pipe of the compressor connected to the outlet of the outdoor heat exchanger during heating operation. The temperature of the suction pipe of the compressor corresponds to the temperature on the outlet side of the outdoor heat exchanger. The second temperature detector is an existing one for detecting the degree of superheat, and is used for detecting frost formation.

本発明によると、室外熱交換器への着霜を正確に判定できるので、着霜していないにもかかわらず除霜運転が行われるといったことを防ぐことができる。特に、運転停止状態から急速暖房を行う場合、圧縮機が低回転から高回転運転になる場合や室内外の配管が長い場合に、着霜していると誤判定しやすいが、これらの場合においても、誤ることなく着霜の有無を検出することができる。   According to the present invention, since frost formation on the outdoor heat exchanger can be accurately determined, it is possible to prevent the defrosting operation from being performed even though frost formation is not performed. In particular, when rapid heating is performed from a shutdown state, it is easy to mistakenly determine that frost has formed when the compressor changes from low rotation to high rotation or when the indoor and outdoor piping is long. In addition, the presence or absence of frost can be detected without error.

このように正確な着霜の判定によって、暖房運転中の不要な除霜運転がなくなり、暖房能力の低下を招くことがなく、省エネ効果の高い空気調和機を実現できる。   Thus, an accurate defrosting determination eliminates unnecessary defrosting operation during heating operation, and does not cause a decrease in heating capacity, thereby realizing an air conditioner with a high energy saving effect.

本実施形態の空気調和機を図１に示す。空気調和機では、圧縮機１、四方弁２、室内熱交換器３、膨張弁４および室外熱交換器５が配管によって接続され、冷凍サイクルが形成される。空気調和機は、制御装置６を備える。制御装置６は、暖房運転、冷房運転に応じて圧縮機１、室内ファン７、室外ファン８、膨張弁４および四方弁２を駆動制御する。暖房運転時には、図中矢印で示すように、冷媒が流れ、冷房運転時には、四方弁２が切り替えられ、逆方向に冷媒が流れる。   The air conditioner of this embodiment is shown in FIG. In the air conditioner, the compressor 1, the four-way valve 2, the indoor heat exchanger 3, the expansion valve 4, and the outdoor heat exchanger 5 are connected by piping to form a refrigeration cycle. The air conditioner includes a control device 6. The control device 6 drives and controls the compressor 1, the indoor fan 7, the outdoor fan 8, the expansion valve 4 and the four-way valve 2 according to the heating operation and the cooling operation. During the heating operation, as indicated by the arrows in the figure, the refrigerant flows, and during the cooling operation, the four-way valve 2 is switched and the refrigerant flows in the reverse direction.

そして、室外熱交換器５の温度を検出する第１温度検出器９と、圧縮機１の吸入管の温度を検出する第２温度検出器１０と、室外温度を検出する外気温検出器１１とが設けられている。   And the 1st temperature detector 9 which detects the temperature of the outdoor heat exchanger 5, the 2nd temperature detector 10 which detects the temperature of the suction pipe of the compressor 1, and the outdoor temperature detector 11 which detects outdoor temperature Is provided.

第１温度検出器９は、暖房運転時における室外熱交換器５の入口側近傍に取り付けられ、暖房運転時に室外熱交換器５に流入する冷媒の温度を検出する。第２温度検出器１０は、圧縮機１の吸入管に取り付けられ、圧縮機１に流入する冷媒の温度を検出する。すなわち、室外熱交換器５の出口側の温度を検出することになる。外気温検出器１１は、室外温度を検出する。   The first temperature detector 9 is attached in the vicinity of the inlet side of the outdoor heat exchanger 5 during the heating operation, and detects the temperature of the refrigerant flowing into the outdoor heat exchanger 5 during the heating operation. The second temperature detector 10 is attached to the suction pipe of the compressor 1 and detects the temperature of the refrigerant flowing into the compressor 1. That is, the temperature on the outlet side of the outdoor heat exchanger 5 is detected. The outside air temperature detector 11 detects the outdoor temperature.

制御装置６は、各温度検出器９、１０、１１により検出した温度に基づいて暖房運転および冷房運転の制御を行う。また、制御装置６は、各温度検出器９、１０、１１により検出した温度に基づいて室外熱交換器５の着霜を判断し、着霜と判定したときには除霜運転を行う。   The control device 6 controls the heating operation and the cooling operation based on the temperatures detected by the temperature detectors 9, 10, and 11. Moreover, the control apparatus 6 judges frost formation of the outdoor heat exchanger 5 based on the temperature detected by each temperature detector 9, 10, 11, and performs a defrosting operation when it determines with frost formation.

着霜の判定としては、外気温Ｔｏと第１温度検出器９による室外熱交換器５の入口側の温度（室外熱交換器温度）Ｔｃとの差Ｔｄｃ（＝Ｔｏ−Ｔｃ）が所定値Ｔｍ１より大きいかを判定するとともに、外気温Ｔｏと第２温度検出器１０による圧縮機１の吸入管の温度（圧縮機吸入管温度）Ｔｓとの差Ｔｄｓ（＝Ｔｏ−Ｔｓ）が所定値Ｔｍ２より大きいかを判定する。それぞれの差Ｔｄｃ、Ｔｄｓが各所定値Ｔｍ１、Ｔｍ２より大となる状態が一定時間、例えば３〜５分続いたとき、着霜と判定する。いずれか一方の差が所定値Ｔｍ１、Ｔｍ２以下のとき、着霜していないと判定する。また、それぞれの差が各所定値Ｔｍ１、Ｔｍ２より大となる状態が一定時間継続しないときにも、着霜していないと判定する。   As the determination of frost formation, the difference Tdc (= To−Tc) between the outside air temperature To and the temperature (outdoor heat exchanger temperature) Tc of the outdoor heat exchanger 5 by the first temperature detector 9 is a predetermined value Tm1. The difference Tds (= To−Ts) between the outside air temperature To and the temperature of the suction pipe of the compressor 1 (compressor suction pipe temperature) Ts by the second temperature detector 10 is determined from the predetermined value Tm2. Determine if it is larger. When the respective differences Tdc and Tds are larger than the predetermined values Tm1 and Tm2 for a certain time, for example, 3 to 5 minutes, it is determined that frost is formed. When any one of the differences is equal to or less than the predetermined values Tm1 and Tm2, it is determined that frost is not formed. Further, it is determined that frosting has not occurred even when a state in which the respective differences are greater than the predetermined values Tm1 and Tm2 does not continue for a certain period of time.

各所定値Ｔｍ１、Ｔｍ２は、圧縮機１の回転数に応じて設定される。図２に外気温度Ｔｏと除霜判定室外熱交換器温度Ｔｃの関係を示す。外気温Ｔｏが低いほど除霜判定室外熱交換器温度Ｔｃを低く、外気温Ｔｏが高いほど除霜判定室外熱交換器温度Ｔｃを高く設定する。同じ着霜量であっても、外気温Ｔｏが低いほど冷媒の蒸発温度が低くなる。そのため、低い室外熱交換器温度で判定して除霜運転を行うようにしないと、着霜量が少ないうちに除霜運転に入ってしまう。その結果、無駄な電力の消費となり、また快適な暖房運転を損なうことになる。逆に外気温Ｔｏが高いときには、冷媒の蒸発温度が高くなるため、高い室外熱交換器温度で判定して除霜を行わないと、着霜量が過剰になってしまう。その結果、除霜運転に時間がかかりすぎたり、快適な暖房運転が損なわれたりする。   The predetermined values Tm1 and Tm2 are set according to the rotation speed of the compressor 1. FIG. 2 shows the relationship between the outside air temperature To and the defrost determination outdoor heat exchanger temperature Tc. The defrost determination outdoor heat exchanger temperature Tc is set lower as the outside air temperature To is lower, and the defrost determination outdoor heat exchanger temperature Tc is set higher as the outside air temperature To is higher. Even with the same amount of frost formation, the lower the outside air temperature To, the lower the evaporation temperature of the refrigerant. For this reason, if the defrosting operation is not performed by determining at a low outdoor heat exchanger temperature, the defrosting operation is started while the amount of frost formation is small. As a result, useless electric power is consumed, and comfortable heating operation is impaired. On the other hand, when the outside air temperature To is high, the evaporation temperature of the refrigerant becomes high. Therefore, if the defrosting is not performed based on the high outdoor heat exchanger temperature, the amount of frost formation becomes excessive. As a result, the defrosting operation takes too much time, or the comfortable heating operation is impaired.

また、圧縮機回転数が高いほど除霜判定室外熱交換器温度Ｔｃを低く、圧縮機回転数が低いほど除霜判定室外熱交換器温度Ｔｃを高く設定する。外気温Ｔｏが同じ場合には、同じ着霜量であっても圧縮機回転数が高いほど冷媒の蒸発温度が低くなる。そのため、低い室外熱交換器温度で判定して除霜運転を行うようにしないと、着霜量が少ないうちに除霜運転に入ってしまう。その結果、無駄な電力の消費となり、また快適な暖房運転を損なうことになる。逆に圧縮機回転数が低いときには、冷媒の蒸発温度が高くなるため、高い室外熱交換器温度で判定して除霜を行わないと、着霜量が過剰になってしまう．その結果、除霜運転に時間がかかりすぎたり、快適な暖房運転が損なわれたりする。   Further, the higher the compressor speed, the lower the defrost determination outdoor heat exchanger temperature Tc, and the lower the compressor speed, the higher the defrost determination outdoor heat exchanger temperature Tc. When the outside air temperature To is the same, the evaporation temperature of the refrigerant decreases as the compressor rotational speed increases even with the same amount of frost formation. For this reason, if the defrosting operation is not performed by determining at a low outdoor heat exchanger temperature, the defrosting operation is started while the amount of frost formation is small. As a result, useless electric power is consumed, and comfortable heating operation is impaired. Conversely, when the compressor speed is low, the evaporation temperature of the refrigerant is high, and therefore the amount of frost formation becomes excessive unless defrosting is performed at a high outdoor heat exchanger temperature. As a result, the defrosting operation takes too much time, or the comfortable heating operation is impaired.

例えば図２において、圧縮機１の回転数がＮ３、外気温Ｔｏが２℃の場合、室外熱交換器５の温度Ｔｃが−８℃に下がれば、室外熱交換器５に適当な量の霜が付着したと判定され、除霜運転が行われることになる。よって、外気温Ｔｏと第１温度検出器９による室外熱交換器５の入口側の温度（室外熱交換器温度）Ｔｃとの差Ｔｄｃが、［２−（−８）］＝１０となれば、着霜と判定する。すなわち、所定値Ｔｍ１は１０とする。   For example, in FIG. 2, when the rotation speed of the compressor 1 is N3 and the outdoor temperature To is 2 ° C., if the temperature Tc of the outdoor heat exchanger 5 is lowered to −8 ° C., an appropriate amount of frost is added to the outdoor heat exchanger 5. Is determined to be attached, and the defrosting operation is performed. Therefore, if the difference Tdc between the outside air temperature To and the temperature (outdoor heat exchanger temperature) Tc on the inlet side of the outdoor heat exchanger 5 by the first temperature detector 9 is [2 − (− 8)] = 10. The frost is determined. That is, the predetermined value Tm1 is 10.

図２において、除霜判定室外熱交換器温度Ｔｃを圧縮機１の吸入管の温度（圧縮機吸入管温度）Ｔｓに置き換えて、同様の関係から所定値Ｔｍ２を設定することができる。なお、所定値Ｔｍ１、Ｔｍ２は同じ値でなくてもよい。以下の説明では、同じ値として説明を行う。   In FIG. 2, the defrost determination outdoor heat exchanger temperature Tc can be replaced with the suction pipe temperature (compressor suction pipe temperature) Ts of the compressor 1 to set the predetermined value Tm2 from the same relationship. The predetermined values Tm1 and Tm2 may not be the same value. In the following description, the same value will be described.

運転停止状態から暖房運転を開始した場合の室外熱交換器５の入口側の温度（室外熱交換器温度）Ｔｃと圧縮機１の吸入管の温度（圧縮機吸入管温度）Ｔｓの時間的変化を図３に示す。運転開始時において、圧縮機１が高回転で駆動されて高回転になるほど、室外熱交換器５の入口側の温度（室外熱交換器温度）Ｔｃは大きく低下し、その時間も長くなる。また、配管が長い場合でも、室外熱交換器温度Ｔｃは大きく低下する。このとき、室外熱交換器５には着霜していないので、熱交換は正常に行われる。圧縮機１の吸入管では、冷媒は加熱状態のガスであるため、圧縮機吸入管温度Ｔｓは室外熱交換器温度Ｔｃに比べて高い。時間の経過とともに冷凍サイクルの状態が安定してくると、室外熱交換器温度Ｔｃは上昇していき、着霜の進行が無ければ蒸発温度で安定する。圧縮機吸入管温度Ｔｓも同じ蒸発温度に加熱度分高い温度で安定する。図３では約１℃程度の加熱度となる。   Temporal changes in the temperature on the inlet side of the outdoor heat exchanger 5 (outdoor heat exchanger temperature) Tc and the temperature of the suction pipe of the compressor 1 (compressor suction pipe temperature) Ts when the heating operation is started from the operation stop state Is shown in FIG. At the start of operation, as the compressor 1 is driven at a higher speed and becomes a higher speed, the temperature on the inlet side of the outdoor heat exchanger 5 (outdoor heat exchanger temperature) Tc greatly decreases and the time also increases. Moreover, even when the piping is long, the outdoor heat exchanger temperature Tc greatly decreases. At this time, since the outdoor heat exchanger 5 is not frosted, heat exchange is normally performed. In the suction pipe of the compressor 1, since the refrigerant is a heated gas, the compressor suction pipe temperature Ts is higher than the outdoor heat exchanger temperature Tc. When the state of the refrigeration cycle becomes stable with the passage of time, the outdoor heat exchanger temperature Tc rises, and if there is no progress of frosting, it stabilizes at the evaporation temperature. The compressor suction pipe temperature Ts is also stabilized at the same evaporation temperature at a temperature higher by the heating degree. In FIG. 3, the heating degree is about 1 ° C.

外気温Ｔｏと室外熱交換器温度Ｔｃとの差Ｔｄｃおよび外気温Ｔｏと圧縮機吸入管温度Ｔｓとの差Ｔｄｓの時間的変化を図４に示す。外気温Ｔｏと室外熱交換器温度Ｔｃとの差Ｔｄｃは、運転を開始して数分後には所定値Ｔｍ１（例として１０とする）を超える。一方、外気温Ｔｏと圧縮機吸入管温度Ｔｓとの差Ｔｄｓは、所定値Ｔｍ２（例として１０とする）を超えていない。したがって、外気温Ｔｏと室外熱交換器温度Ｔｃとの差Ｔｄｃが一定時間、所定値Ｔｍ１より大きくなっても、Ｔｄｓは所定値Ｔｍ２よりも大きくならないので、制御装置６は、着霜とは判定しない。そのため、除霜運転は行わない。   FIG. 4 shows temporal changes in the difference Tdc between the outside air temperature To and the outdoor heat exchanger temperature Tc and the difference Tds between the outside air temperature To and the compressor suction pipe temperature Ts. A difference Tdc between the outside air temperature To and the outdoor heat exchanger temperature Tc exceeds a predetermined value Tm1 (for example, 10) several minutes after the operation is started. On the other hand, the difference Tds between the outside air temperature To and the compressor suction pipe temperature Ts does not exceed a predetermined value Tm2 (for example, 10). Therefore, even if the difference Tdc between the outside air temperature To and the outdoor heat exchanger temperature Tc is larger than the predetermined value Tm1 for a certain period of time, Tds does not become larger than the predetermined value Tm2. do not do. Therefore, defrosting operation is not performed.

ここで、従来のように、外気温Ｔｏと室外熱交換器温度Ｔｃとの差Ｔｄｃだけで着霜を判定すると、この差が一定時間所定値Ｔｍ１を超えるので、着霜と判定される。その結果、実際には着霜していないにもかかわらず、除霜運転が行われてしまう。しかし、上記のように２つの温度差に基づいて着霜を判定すれば、着霜の誤判定はなくなり、不要な除霜運転は行われない。   Here, if frost formation is determined only by the difference Tdc between the outside air temperature To and the outdoor heat exchanger temperature Tc as in the conventional case, this difference exceeds the predetermined value Tm1 for a certain period of time, so that it is determined as frost formation. As a result, the defrosting operation is performed even though the frost is not actually formed. However, if frost formation is determined based on the two temperature differences as described above, erroneous determination of frost formation is eliminated, and unnecessary defrosting operation is not performed.

暖房運転時の室外熱交換器５への着霜が進行していく場合の時間的変化を図５に示す。暖房運転が継続されると、室外熱交換器５に霜が着き始める。すると、室外熱交換器５の吸熱量が低下していき、室外熱交換器５において冷媒が十分に蒸発しきらずに、ガス液混合状態の冷媒となる。この状態の冷媒が圧縮機１の吸入管に流れ込む。したがって、図５に示すように、圧縮機吸入管温度Ｔｓおよび室外熱交換器温度Ｔｃは徐々に低下する。このとき、外気温Ｔｏと室外熱交換器温度Ｔｃとの差Ｔｄｃおよび外気温Ｔｏと圧縮機吸入管温度Ｔｓとの差Ｔｄｓは、図６に示すように、霜が着き始めるのに伴って大きくなる。それぞれの差が一定時間、所定値Ｔｍ１、Ｔｍ２より大きくなると、制御装置６は、着霜と判定し、除霜運転を開始する。   FIG. 5 shows temporal changes when frost formation on the outdoor heat exchanger 5 during heating operation proceeds. When the heating operation is continued, frost starts to form on the outdoor heat exchanger 5. Then, the heat absorption amount of the outdoor heat exchanger 5 decreases, and the refrigerant does not evaporate sufficiently in the outdoor heat exchanger 5 and becomes a refrigerant in a gas-liquid mixed state. The refrigerant in this state flows into the suction pipe of the compressor 1. Therefore, as shown in FIG. 5, the compressor suction pipe temperature Ts and the outdoor heat exchanger temperature Tc gradually decrease. At this time, the difference Tdc between the outside air temperature To and the outdoor heat exchanger temperature Tc and the difference Tds between the outside air temperature To and the compressor suction pipe temperature Ts increase as frost starts to form, as shown in FIG. Become. When each difference becomes larger than the predetermined values Tm1 and Tm2 for a certain period of time, the control device 6 determines frost formation and starts the defrosting operation.

このように、室外熱交換器５の入口側および出口側の２つの温度と外気温Ｔｏに基づいて着霜を判定することにより、着霜を正確に判定することができる。着霜していないにもかかわらず、誤って除霜運転が行われることを防止できる。したがって、暖房運転を開始するとき、急速運転のように圧縮機１を高周波数で運転する場合や長尺配管の場合に、室外熱交換器５の入口側の温度が急激に低下しても、着霜とは判定せず、除霜運転を行わない。   Thus, frost formation can be accurately determined by determining frost formation based on the two temperatures on the inlet side and the outlet side of the outdoor heat exchanger 5 and the outside air temperature To. Although the frost is not formed, it is possible to prevent the defrosting operation from being erroneously performed. Therefore, when the heating operation is started, even when the compressor 1 is operated at a high frequency like a rapid operation or in the case of a long pipe, even if the temperature on the inlet side of the outdoor heat exchanger 5 rapidly decreases, It does not determine with frost formation and does not perform defrost operation.

また、圧縮機１の吸入管の温度を検出する第２温度検出器１０は、膨張弁４を有する冷凍サイクルにおいて、暖房運転および冷房運転での過熱度制御用のために従来から使用されている。この温度検出器１０を着霜検出用に利用するので、新たに温度検出器を設置する必要はない。   The second temperature detector 10 that detects the temperature of the suction pipe of the compressor 1 is conventionally used in the refrigeration cycle having the expansion valve 4 for controlling the degree of superheat in heating operation and cooling operation. . Since this temperature detector 10 is used for detecting frost formation, there is no need to newly install a temperature detector.

なお、本発明は、上記実施形態に限定されるものではなく、本発明の範囲内で上記実施形態に多くの修正および変更を加え得ることは勿論である。室外熱交換器の出口側の温度として、圧縮機の吸入管の温度を検出する代わりに、暖房運転時における室外熱交換器の出口側と圧縮機の吸入管との間に第２温度検出器を設けてもよい。この第２温度検出器は、室外熱交換器の出口側と圧縮機とを接続する配管を流れる冷媒の温度を検出する。   In addition, this invention is not limited to the said embodiment, Of course, many corrections and changes can be added to the said embodiment within the scope of the present invention. Instead of detecting the temperature of the suction pipe of the compressor as the temperature of the outlet side of the outdoor heat exchanger, a second temperature detector is provided between the outlet side of the outdoor heat exchanger and the suction pipe of the compressor during heating operation. May be provided. This 2nd temperature detector detects the temperature of the refrigerant | coolant which flows through the piping which connects the exit side of an outdoor heat exchanger, and a compressor.

本発明の空気調和機の全体構成図Overall configuration diagram of the air conditioner of the present invention 外気温度と除霜判定室外熱交換器温度の関係を示す図The figure which shows the relationship between outside temperature and defrost determination outdoor heat exchanger temperature 暖房運転開始時の室外熱交換器温度および圧縮機吸入管温度の時間的変化を示す図The figure which shows the time change of the outdoor heat exchanger temperature at the time of heating operation start, and the compressor suction pipe temperature 暖房運転開始時の外気温と室外熱交換器温度および圧縮機吸入管温度との差の時間的変化を示す図The figure which shows the time change of the difference of the external temperature at the time of heating operation start, outdoor heat exchanger temperature, and compressor suction pipe temperature 暖房運転時の室外熱交換器への着霜が進行していく場合の室外熱交換器温度および圧縮機吸入管温度の時間的変化を示す図The figure which shows the time change of the outdoor heat exchanger temperature when the frost formation to the outdoor heat exchanger at the time of heating operation progresses, and the compressor suction pipe temperature 暖房運転時の室外熱交換器への着霜が進行していく場合の外気温と室外熱交換器温度および圧縮機吸入管温度との差の時間的変化を示す図The figure which shows the time change of the difference of the outdoor temperature, the outdoor heat exchanger temperature, and the compressor suction pipe temperature when frosting to the outdoor heat exchanger progresses during heating operation

符号の説明Explanation of symbols

１ 圧縮機
２ 四方弁
３ 室内熱交換器
４ 膨張弁
５ 室外熱交換器
６ 制御装置
９ 第１温度検出器
１０ 第２温度検出器
１１ 外気温検出器 DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 4 Expansion valve 5 Outdoor heat exchanger 6 Control apparatus 9 1st temperature detector 10 2nd temperature detector 11 Outside temperature detector

Claims (3)

圧縮機、室内熱交換器、膨張弁および室外熱交換器が配管により連結され、暖房運転中に室外熱交換器への着霜を検出して、除霜運転を行う制御装置と、前記室外熱交換器の入口側の温度を検出する第１温度検出器と、前記室外熱交換器の出口側の温度を検出する第２温度検出器と、室外温度を検出する外気温検出器とが設けられ、前記制御装置は、前記３つの温度に基づいて着霜を判定することを特徴とする空気調和機。 A control device that performs defrosting operation by detecting frost formation on the outdoor heat exchanger during heating operation by connecting a compressor, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger, and the outdoor heat A first temperature detector for detecting the temperature on the inlet side of the exchanger, a second temperature detector for detecting the temperature on the outlet side of the outdoor heat exchanger, and an outside air temperature detector for detecting the outdoor temperature are provided. The air conditioner is characterized in that the control device determines frost formation based on the three temperatures. 制御装置は、室外温度と室外熱交換器の入口側の温度との差および室外温度と室外熱交換器の出口側の温度との差がそれぞれ所定値より大のとき、着霜と判定することを特徴とする請求項１記載の空気調和機。 When the difference between the outdoor temperature and the temperature on the inlet side of the outdoor heat exchanger and the difference between the outdoor temperature and the temperature on the outlet side of the outdoor heat exchanger are each greater than a predetermined value, the control device determines that frost formation has occurred. The air conditioner according to claim 1. 第１温度検出器は、暖房運転時における室外熱交換器の入口近傍に設けられ、第２温度検出器は、暖房運転時に前記室外熱交換器の出口につながる圧縮機の吸入管に設けられたことを特徴とする請求項１または２記載の空気調和機。 The first temperature detector is provided in the vicinity of the inlet of the outdoor heat exchanger during heating operation, and the second temperature detector is provided in the suction pipe of the compressor connected to the outlet of the outdoor heat exchanger during heating operation. The air conditioner according to claim 1 or 2, wherein
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WO2017002618A1 (en) * 2015-07-01 2017-01-05 三菱重工業株式会社 Air conditioning system, control method, and program
WO2017073212A1 (en) * 2015-10-27 2017-05-04 株式会社デンソー Refrigeration cycle device
CN107940677A (en) * 2017-10-31 2018-04-20 青岛海尔空调器有限总公司 A kind of control method and device for slowing down air-conditioner outdoor unit frosting
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JP2010151364A (en) * 2008-12-25 2010-07-08 Panasonic Corp Air conditioner
JP2011202812A (en) * 2010-03-24 2011-10-13 Toshiba Carrier Corp Air conditioner
GB2485623A (en) * 2011-02-11 2012-05-23 Esg Pool Ventilation Ltd Heating system and method of heating an area by control of evaporating and/or condensing temperature of a refrigerant
GB2485623B (en) * 2011-02-11 2012-10-17 Esg Pool Ventilation Ltd Heating and/or cooling system and related methods
US9328931B2 (en) 2011-02-11 2016-05-03 Esg Pool Ventilation Ltd Heating and/or cooling system for maintaining an environment at a desired temperature
JP2014029230A (en) * 2012-07-31 2014-02-13 Chofu Seisakusho Co Ltd Method of determining frost formation on heat pump and heat pump adopting the method
WO2017002618A1 (en) * 2015-07-01 2017-01-05 三菱重工業株式会社 Air conditioning system, control method, and program
JP2017015333A (en) * 2015-07-01 2017-01-19 三菱重工業株式会社 Air conditioning system, control method and program
WO2017073212A1 (en) * 2015-10-27 2017-05-04 株式会社デンソー Refrigeration cycle device
JPWO2017073212A1 (en) * 2015-10-27 2018-03-01 株式会社デンソー Refrigeration cycle equipment
CN108027185A (en) * 2015-10-27 2018-05-11 株式会社电装 Refrigerating circulatory device
CN108027185B (en) * 2015-10-27 2020-06-05 株式会社电装 Refrigeration cycle device
US10845096B2 (en) 2015-10-27 2020-11-24 Denso Corporation Refrigeration cycle device
CN107940677A (en) * 2017-10-31 2018-04-20 青岛海尔空调器有限总公司 A kind of control method and device for slowing down air-conditioner outdoor unit frosting
CN110594959A (en) * 2019-09-18 2019-12-20 宁波奥克斯电气股份有限公司 Air conditioner control method
CN110594959B (en) * 2019-09-18 2021-04-16 宁波奥克斯电气股份有限公司 Air conditioner control method
WO2024001373A1 (en) * 2022-06-30 2024-01-04 海信空调有限公司 Air conditioner and defrosting control method therefor

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