JP2010091118A

JP2010091118A - Air conditioner

Info

Publication number: JP2010091118A
Application number: JP2008258155A
Authority: JP
Inventors: Kenichiro Yano; 謙一郎矢野
Original assignee: Panasonic Corp
Current assignee: Panasonic Corp
Priority date: 2008-10-03
Filing date: 2008-10-03
Publication date: 2010-04-22

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of reducing the generation of refrigerant noise generated in the switching of a four-way valve at starting a heating operation after defrosting. <P>SOLUTION: The air conditioner includes a refrigerant circuit constituted by annularly connecting a frequency-variable compressor 1, the four-way valve 2, an outdoor heat exchanger 5, a pressure-reducing expansion valve 11, and an indoor heat exchanger 3, and a rotational frequency of the compressor 1 during a defrosting operation is reduced according to a rising speed of an outlet temperature of the outdoor heat exchanger 5, thus a pressure difference between discharging and sucking can be suppressed, the generation of refrigerant noise in the switching of the four-way valve 2 when heating is restarted can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、除霜後暖房運転開始時の四方弁切換え時に発生する騒音を低減する空気調和機に関するものである。 The present invention relates to an air conditioner that reduces noise generated when a four-way valve is switched at the start of heating operation after defrosting.

従来、この種の空気調和機の除霜後暖房運転開始時の四方弁切換え時に発生する騒音低減は、除霜運転終了時の圧縮機の電流値を検出し、この電流値に応じて、四方弁を暖房に切換えるまでの時間を変えて、暖房休止時間を短縮するようにしている（例えば、特許文献１参照）。 Conventionally, noise reduction that occurs when switching the four-way valve at the start of heating operation after defrosting of this type of air conditioner detects the current value of the compressor at the end of the defrosting operation, and according to this current value, The time until the valve is switched to heating is changed to shorten the heating pause time (see, for example, Patent Document 1).

図３は、上記特許文献１に記載された従来の空気調和機を構成を示すものである。図３に示すように、１は、圧縮機、２は、四方弁、３は、室内熱交換器、４は、キャプラリチューブ、５は、室外熱交換器、６は、制御部、７は、除霜運転時間等を計時するタイマー、８は、圧縮機１の電流値を検出する電流検出部、９は、除霜運転終了時の圧縮機１の電流値と、各電流値に対応する四方弁２の切換え前の圧縮機１のオフ時間のデータを記憶するメモリ部である。
特開平０７−１７４４４０号公報 FIG. 3 shows a configuration of a conventional air conditioner described in Patent Document 1. As shown in FIG. 3, 1 is a compressor, 2 is a four-way valve, 3 is an indoor heat exchanger, 4 is a capillary tube, 5 is an outdoor heat exchanger, 6 is a control unit, and 7 is a control unit. , A timer for timing the defrosting operation time, 8 is a current detection unit for detecting the current value of the compressor 1, and 9 is a current value of the compressor 1 at the end of the defrosting operation and each current value. It is a memory unit that stores data of the off time of the compressor 1 before switching of the four-way valve 2.
Japanese Unexamined Patent Publication No. 07-174440

しかしながら上記従来の空気調和機の構成では、除霜は終了しているのに除霜運転を継続するカラ除霜により、高圧が上昇し、高圧が上昇する条件ほど除霜運転後から暖房運転開始時の四方弁２の切換えまでの時間を長くして高低圧力差を小さくして騒音を低減するようにしているため、高圧が高いほど、暖房運転再開までの時間がかかり、暖房休止時間が増加し、室温の低下により使用者の快適性を大きく損なうという課題を有していた。 However, in the configuration of the conventional air conditioner described above, although the defrosting is finished, the high pressure rises due to the color defrosting that continues the defrosting operation, and the heating operation starts after the defrosting operation under the condition that the high pressure rises. Since the time until switching of the four-way valve 2 is increased to reduce the noise by reducing the high-low pressure difference, the higher the high pressure, the longer it takes to resume the heating operation and the heating pause time increases. However, there is a problem that the comfort of the user is greatly impaired due to a decrease in room temperature.

本発明は、前記従来の課題を解決するもので、除霜運転終了時の高圧上昇を抑制することにより、四方弁切換え時の騒音を低減し、かつ暖房休止時間の短縮により快適性を向上した空気調和機を提供することを目的とする。 The present invention solves the above-mentioned conventional problems, and by suppressing the increase in high pressure at the end of the defrosting operation, noise at the time of switching the four-way valve is reduced, and comfort is improved by shortening the heating pause time. An object is to provide an air conditioner.

前記従来の課題を解決するために、本発明の空気調和機は、回転数可変の圧縮機と、四方弁と、室外熱交換器と、減圧膨張弁と、室内熱交換器を環状に接続して構成された冷媒回路を備え、除霜運転中の前記圧縮機の回転数を、前記室外熱交換器の出口温度の上昇速度に応じて低減するもので、吐出と吸入の圧力差を抑制でき、暖房再開時の四方弁切換え時に発生する冷媒音の発生を低減することができる。 In order to solve the above-mentioned conventional problems, an air conditioner of the present invention comprises a compressor having a variable number of revolutions, a four-way valve, an outdoor heat exchanger, a decompression expansion valve, and an indoor heat exchanger that are connected in an annular shape. The refrigerant circuit is configured to reduce the rotational speed of the compressor during the defrosting operation according to the rate of increase in the outlet temperature of the outdoor heat exchanger, and can suppress the pressure difference between the discharge and the suction. Further, it is possible to reduce the generation of refrigerant noise that occurs when switching the four-way valve when heating is resumed.

本発明の空気調和機は、除霜制御終了時の吐出圧力を低減することにより、吐出と吸入の圧力差を抑制して、暖房再開時の四方弁切換え時に発生する冷媒音の発生を低減することができる。 The air conditioner of the present invention reduces the pressure difference between discharge and suction by reducing the discharge pressure at the end of the defrost control, and reduces the generation of refrigerant noise that occurs when switching the four-way valve when resuming heating. be able to.

第１の発明は、回転数可変の圧縮機と、四方弁と、室外熱交換器と、減圧膨張弁と、室内熱交換器を環状に接続して構成された冷媒回路を備え、除霜運転中の前記圧縮機の回転数を、前記室外熱交換器の出口温度の上昇速度に応じて低減するもので、吐出と吸入の圧力差を抑制でき、暖房再開時の四方弁切換え時に発生する冷媒音の発生を低減することが
できる。 A first invention includes a refrigerant circuit configured by connecting a compressor having a variable rotation speed, a four-way valve, an outdoor heat exchanger, a decompression expansion valve, and an indoor heat exchanger in an annular manner, and performs a defrosting operation. Reducing the number of rotations of the compressor in accordance with the rising speed of the outlet temperature of the outdoor heat exchanger, can suppress the pressure difference between discharge and suction, and generate refrigerant when switching the four-way valve when resuming heating Generation of sound can be reduced.

第２の発明は、特に、第１の発明の空気調和機は、外気温度に応じて除霜開始時の圧縮機の回転数を変えるもので、外気温度が低い場合は高回転で、外気温が高い場合は低回転で除霜を開始するので、外気温が高いときに高圧が急激に上昇することを抑制できる。 In the second invention, in particular, the air conditioner of the first invention changes the rotation speed of the compressor at the start of defrosting according to the outside air temperature. When the temperature is high, the defrosting is started at a low rotation, so that the high pressure can be prevented from rapidly increasing when the outside air temperature is high.

第３の発明は、特に、第１又は第２の発明の空気調和機は、高圧圧力と低圧圧力の差が第１の所定値以下になってから四方弁を暖房運転側に切換えるもので、圧縮機を停止させることなく四方弁の切換えを行え、騒音を常に一定のレベルとすることができ、暖房運転再開までの時間を短縮することにより快適性を向上できる。 In the third aspect of the invention, in particular, the air conditioner of the first or second aspect of the invention switches the four-way valve to the heating operation side after the difference between the high pressure and the low pressure is equal to or less than the first predetermined value. The four-way valve can be switched without stopping the compressor, the noise can be kept at a constant level, and the comfort can be improved by shortening the time until the heating operation is resumed.

第４の発明は、特に、第３の発明の圧縮機の電流値により、高圧圧力と低圧圧力の差を判定するもので、圧力検出器を備えていない空気調和機においても四方弁切換え時の騒音を常に一定のレベルとすることができる。 In the fourth aspect of the invention, in particular, the difference between the high pressure and the low pressure is determined based on the current value of the compressor of the third aspect of the invention. Even in an air conditioner not equipped with a pressure detector, the four-way valve is switched. Noise can always be at a constant level.

第５の発明は、特に、第３又は第４の発明の四方弁を切換える際の高圧圧力と低圧圧力の差である第１の所定値を選択するためのコントローラを設けたもので、騒音が問題にならない条件では、第１の所定値を初期値より高く設定し四方弁を切換えて暖房再開までの時間を短縮でき、一方騒音が非常に気になる条件では第１の所定値を初期値より低く設定することにより、四方弁切換え時の騒音をより小さくする運転となるように選択することができる。 The fifth invention is provided with a controller for selecting a first predetermined value which is the difference between the high pressure and the low pressure when the four-way valve of the third or fourth invention is switched. Under non-problematic conditions, the first predetermined value can be set higher than the initial value and the four-way valve can be switched to shorten the time until resumption of heating. On the other hand, when the noise is very worrisome, the first predetermined value is set to the initial value. By setting the value lower, it is possible to select the operation so as to reduce the noise when switching the four-way valve.

以下、本発明の実施の形態について、図面を参照しながら説明する。なお、この実施の形態によって本発明が限定されるものではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

（実施の形態１）
図１は、本発明の第１の実施の形態における空気調和機の構成図、図２は、同空気調和機の制御フローチャートである。 (Embodiment 1)
FIG. 1 is a configuration diagram of an air conditioner according to the first embodiment of the present invention, and FIG. 2 is a control flowchart of the air conditioner.

図１において、１は、周波数可変型の圧縮機で、その電源周波数を変化させることにより圧縮機１の回転数を変化させ、容量を制御するものである。この圧縮機１から吐出された冷媒は、四方弁２を通り、暖房時は、室内熱交換器３で液化凝縮され、減圧膨張弁１１で減圧膨張し、室外熱交換器５で吸熱し、除霜時は、室外熱交換器５で液化凝縮し除霜を行い、減圧膨張弁１１で、減圧膨張し、室内熱交換器３で吸熱し、四方弁２を経て圧縮機１へ吸入される。 In FIG. 1, reference numeral 1 denotes a variable frequency compressor, which changes the power frequency to change the number of revolutions of the compressor 1 to control the capacity. The refrigerant discharged from the compressor 1 passes through the four-way valve 2 and is liquefied and condensed by the indoor heat exchanger 3 during heating, is decompressed and expanded by the decompression expansion valve 11, absorbs heat by the outdoor heat exchanger 5, and is removed. At the time of frosting, it is liquefied and condensed by the outdoor heat exchanger 5 to perform defrosting, decompressed and expanded by the decompression expansion valve 11, absorbed by the indoor heat exchanger 3, and sucked into the compressor 1 through the four-way valve 2.

１４は、室外熱交換器５の温度から着霜を検出する室外熱交温度センサ、１７は、除霜時の室外熱交換器５の出口温度から除霜度合いを検出する除霜センサ、１２は、外気温度を検出する外気温度センサ、１５は、制御装置で圧縮機１の電流値も検出する。１６は、空気調和機のコントローラで、四方弁２を切換える際の第１の所定値を選択できる機能も備えている。 14 is an outdoor heat exchange temperature sensor that detects frost formation from the temperature of the outdoor heat exchanger 5, 17 is a defrost sensor that detects the degree of defrost from the outlet temperature of the outdoor heat exchanger 5 during defrosting, and 12 is The outside air temperature sensor 15 for detecting the outside air temperature also detects the current value of the compressor 1 by the control device. Reference numeral 16 denotes an air conditioner controller that also has a function of selecting a first predetermined value when switching the four-way valve 2.

以上のように構成された本実施の形態における空気調和機について、図２のフローチャートを用いて以下その動作、作用を説明する。 About the air conditioner in this Embodiment comprised as mentioned above, the operation | movement and an effect | action are demonstrated below using the flowchart of FIG.

暖房運転中に、室外熱交温度センサ１４の検出値が除霜運転開始条件を満たすと、圧縮機１の回転数を所定の低速一定回転数としてから、四方弁２を除霜側へ切換え、外気温センサ１２の検出値に応じた回転数で、圧縮機１を運転し除霜運転を開始する。 If the detected value of the outdoor heat exchanger temperature sensor 14 satisfies the defrosting operation start condition during the heating operation, the four-way valve 2 is switched to the defrosting side after setting the rotation speed of the compressor 1 to a predetermined low speed constant rotation speed, The compressor 1 is operated at the number of rotations corresponding to the detection value of the outside air temperature sensor 12, and the defrosting operation is started.

除霜が進むと、除霜センサ１７の検出値が上昇を始める。除霜中は、所定時間毎に除霜
センサ１７の前回の検出値と今回の検出値の差を監視し、その差に応じて圧縮機１の回転数を減速させる。 When the defrosting progresses, the detection value of the defrosting sensor 17 starts to rise. During the defrosting, the difference between the previous detection value and the current detection value of the defrost sensor 17 is monitored every predetermined time, and the rotational speed of the compressor 1 is decelerated according to the difference.

除霜センサ１７が除霜完了の所定値まで達した後は、圧縮機１の回転数を低速で一定とし、制御装置１５で検出される圧縮機１の電流が高圧圧力と低圧圧力の差が所定値となる第１の所定値以下となる値になれば、四方弁２を、暖房側へ切換え暖房運転を再開する。 After the defrost sensor 17 reaches a predetermined value for completion of defrosting, the rotation speed of the compressor 1 is kept constant at a low speed, and the current of the compressor 1 detected by the control device 15 is the difference between the high pressure and the low pressure. When the value becomes equal to or less than the first predetermined value, which is a predetermined value, the four-way valve 2 is switched to the heating side and the heating operation is resumed.

以上のように、本実施の形態においては、除霜完了前に圧縮機１の回転数を低下させてから四方弁２の切換えを一定の高低圧力差で行うため、除霜終了後から四方弁２の切換えまでのカラ除霜による高圧の上昇を抑制し、カラ除霜時間を短縮したうえで常に切換え時の騒音を所定レベル以下に抑えることができる。 As described above, in the present embodiment, the four-way valve 2 is switched at a constant high and low pressure difference after the rotation speed of the compressor 1 is reduced before the defrosting is completed. It is possible to suppress the increase in high pressure due to the color defrosting until the switching of 2 and shorten the time for the color defrosting, and to always suppress the noise at the time of switching to a predetermined level or less.

また、本実施の形態では、コントローラ１６で四方弁２の切換え時の圧力差である第１の所定値を設定でき、騒音レベルが問題ない運転条件においては第１の所定値を高く設定し、除霜終了後から四方弁２の切換えまでの時間を短縮でき、一方騒音が気になる条件では第１の所定値を低く設定し、圧力差が小さい条件で四方弁２を切換えするので切換え時の騒音をより小さくすることができる。 In the present embodiment, the controller 16 can set the first predetermined value, which is the pressure difference when switching the four-way valve 2, and set the first predetermined value high in operating conditions where there is no problem with the noise level. The time from the end of defrosting to the switching of the four-way valve 2 can be shortened. On the other hand, the first predetermined value is set low when the noise is a concern, and the four-way valve 2 is switched under a small pressure difference. The noise can be further reduced.

以上のように、本発明にかかる空気調和機は、四方弁切換え時に発生する騒音を抑制できるもので、四方弁を用いた自動販売機等の用途にも適用できる。 As described above, the air conditioner according to the present invention can suppress noise generated when the four-way valve is switched, and can be applied to applications such as a vending machine using the four-way valve.

本発明の実施の形態１における空気調和機の構成図The block diagram of the air conditioner in Embodiment 1 of this invention 同空気調和機の制御フローチャートControl flow chart of the air conditioner 従来の空気調和機のサイクルと制御装置の概略図Schematic of conventional air conditioner cycle and control device

符号の説明Explanation of symbols

１圧縮機
２四方弁
３室内熱交換器
５室外熱交換器
１１減圧膨張弁
１２外気温センサ
１４室外熱交温度センサ
１５制御装置
１６コントローラ
１７除霜センサ DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 5 Outdoor heat exchanger 11 Pressure-reduction expansion valve 12 Outdoor temperature sensor 14 Outdoor heat exchanger temperature sensor 15 Controller 16 Controller 17 Defrost sensor

Claims

回転数可変の圧縮機と、四方弁と、室外熱交換器と、減圧膨張弁と、室内熱交換器を環状に接続して構成された冷媒回路を備え、除霜運転中の前記圧縮機の回転数を、前記室外熱交換器の出口温度の上昇速度に応じて低減することを特徴とした空気調和機。 A compressor having a variable number of revolutions, a four-way valve, an outdoor heat exchanger, a decompression expansion valve, and a refrigerant circuit configured by annularly connecting an indoor heat exchanger, the compressor during the defrosting operation An air conditioner characterized in that the number of rotations is reduced in accordance with the rising speed of the outlet temperature of the outdoor heat exchanger.

外気温度に応じて除霜開始時の圧縮機の回転数を変えることを特徴とした請求項１に記載の空気調和機。 The air conditioner according to claim 1, wherein the rotation speed of the compressor at the start of defrosting is changed according to the outside air temperature.

高圧圧力と低圧圧力の差が第１の所定値以下になってから四方弁を暖房運転側に切換えることを特徴とした請求項１又は２に記載の空気調和機。 The air conditioner according to claim 1 or 2, wherein the four-way valve is switched to the heating operation side after the difference between the high pressure and the low pressure is equal to or less than a first predetermined value.

圧縮機の電流値により、高圧圧力と低圧圧力の差を判定することを特徴とした請求項３に記載の空気調和機。 The air conditioner according to claim 3, wherein a difference between the high pressure and the low pressure is determined based on a current value of the compressor.

四方弁を切換える際の高圧圧力と低圧圧力の差である第１の所定値を選択するためのコントローラを設けたことを特徴とした請求項３又は４に記載の空気調和機。 The air conditioner according to claim 3 or 4, further comprising a controller for selecting a first predetermined value which is a difference between a high pressure and a low pressure when the four-way valve is switched.