JP4211432B2

JP4211432B2 - Air conditioner refrigerant relay unit

Info

Publication number: JP4211432B2
Application number: JP2003050709A
Authority: JP
Inventors: 典秀風村; 建吾高橋; 寿彦榎本
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2003-02-27
Filing date: 2003-02-27
Publication date: 2009-01-21
Anticipated expiration: 2023-02-27
Also published as: JP2004257686A

Description

【０００１】
【発明の属する技術分野】
本発明は、空気調和機の室内機と室外機を接続する冷媒配管に設けられ、１台の室外機から１台または複数の室内機へ冷媒を流通させる空気調和機の冷媒中継ユニットに関するものである。
【０００２】
【従来の技術】
従来、１つの室外機と複数の室内機とが接続されるマルチタイプの空気調和機における室内機には、熱交換器と冷媒循環量の調整や遮断を行う電動膨張弁と、熱交換器の過熱度または過冷却度を検知するために熱交換器前後に配管温度センサが取り付けられ、この検知温度情報により電動膨張弁の開度制御を行っている。そして、このような室内機を用いれば、室外機側にて接続された室内機毎に必要な冷媒を分流させるための冷媒分流機構（ヘッダーなど）を用いずに、室内機と室外機を接続する延長配管内の任意の位置で冷媒を分配するとよい。
【０００３】
一方、１つの室外機に１つの室内機が接続される１：１タイプの空気調和機における室内機には、室内機毎に冷媒循環量の調整や冷媒の遮断をする必要がないため、室内機側に電動膨張弁をもっていない。そのため、室内機側に設けた配管温度センサの使用数や設置位置もマルチタイプの室内機と一般的には異なっている。そのため、１：１タイプの室内機をマルチタイプの室外機に接続する場合は、電動膨張弁とその開度制御を行うための配管温度センサを室内機の外部に設ける必要があり、室内機と室外機の間にこれらを内蔵した中継ユニットを設けていた。
【０００４】
従来の中継ユニットは室外機及び室内機から液管とガス管が接続され、さらに室外機側の液管と室内機側の液管とは気液熱交換ユニットを介して接続され、また冷房時の減圧および暖房時の冷媒分配のための電動膨張弁が設けられている。さらに、この冷媒中継ユニットの室内機側のガス管には冷媒温度を検出するガス管サーミスタが設けられている。（例えば、特許文献１参照）
【０００５】
【特許文献１】
特開２００１−２４１６９７号公報（第３頁〜第４頁、図１、図２）
【０００６】
【発明が解決しようとする課題】
しかしながら、従来の冷媒中継ユニットによる冷媒回路構成では、室内機（室内熱交換器）と中継ユニット内に設けられた電動膨張弁との距離が設置条件によって大きく異なるとき、例えばその距離が大きくなったり小さくなったりした場合、室内機と中継ユニット間の延長配管による配管流路圧損により、冷媒の状態が変化して温度センサによる検出温度が大きく影響を受けるため、マルチタイプ室内機用の冷房入口側にて検出していた冷媒の蒸発温度の検出精度も配管長さによって変化する。それにより実際の蒸発器過熱度を正確に把握できなくなり、冷房能力不足や熱交換器の乾きによる露飛び等が発生する問題がある。
【０００７】
この発明は上記課題を解決するためになされたもので、室内機と室外機を接続する延長配管の長さに係わらず室内機の負荷に応じた必要な冷媒流量を確保できる空気調和機の冷媒中継ユニットを提供することを目的とする。
【０００８】
【課題を解決するための手段】
本発明の空気調和機の冷媒中継ユニットは、室内熱交換器を有した室内機と少なくとも圧縮機および室外熱交換器を有した室外機とを延長配管を介して冷媒を循環させる空気調和機の冷媒中継ユニットにおいて、前記延長配管の液側配管に設けて冷媒を減圧する減圧装置と前記室内熱交換器の冷媒過熱度を検知する過熱度検知手段を備えたものである。
【０００９】
また、本発明の空気調和機の冷媒中継ユニットは、過熱度検知手段がガス側配管に設けられた第１配管温度センサおよび液側配管とガス側配管を減圧機構を介して接続するバイパス回路に設けられた第２配管温度センサからなるものである。
【００１０】
また、本発明の空気調和機の冷媒中継ユニットは、減圧手段を収納した筐体に、室外機に設けた室外機制御装置および室内機に設けた室内機制御装置と相互に運転情報を伝送できる中継ユニット制御装置を備えたものである。
【００１１】
【発明の実施の形態】
実施の形態１．
以下、本発明の実施の形態１の空気調和機の冷媒中継ユニットについて、図１から図７を用いて説明する。
図１は本実施の形態に係わる空気調和機のシステムを示す冷媒回路図である。図において、この空気調和機は１台の室外機１０と、１台もしくは複数台の室内機３０と、室内機の台数に対応した冷媒中継ユニット２０から構成されている。この室外機１０には、冷凍サイクルを構成する主要部品の圧縮機、アキュムレータ、室外側熱交換器や、室外空気と冷媒との間で熱交換させるために外気を熱交換器へ送風するファンが搭載されている。また、空気調和機のシステム全体をコントロールするための室外機制御装置１１も搭載しており、空調負荷に応じた圧縮機運転周波数や冷媒の絞り量を調整するための電動膨張弁の開度制御を行う。
【００１２】
電動膨張弁の開度制御は、図４に示すように冷房時は各室内側熱交換器の出口側冷媒過熱度を所定の目標値になるように調整する開度指令を行う。例えば、蒸発側熱交換器に設けた蒸発温度検知センサと蒸発器出口側に接続した配管に設けられたガス管温度検知センサの検出温度の差をその室内機の過熱度（ＳＨ）とする。過熱度ＳＨは室内機側の空調負荷と冷媒流量により変化するので、測定検知された過熱度が予め決められた目標過熱度ＳＨｍ（例えば３ｄｅｇ）になっているかどうか判断し、検出した過熱度が目標過熱度になっていない場合には、ΔＳＨ（＝ＳＨ−ＳＨｍ）に応じて予め決められた膨張弁開度分だけの開度Ｌｊに補正量ΔＬｊを加算する。なお、この演算は室外機の制御装置にて実施するので、各温度センサ（温度検出手段）により検出される温度情報を通信により室外機の制御装置が入手し、冷凍サイクルの冷媒状態を示すそれらの温度情報をもとに膨張弁指令開度を演算し、その演算結果を室外機制御装置から中継ユニット制御装置へ返信し、電動膨張弁に開度を指令する。図５にΔＳＨに応じた電動膨張弁開度補正量ΔＬｊを示す。
また、室内機は、図２に示す１：１タイプ用室内機３０のように冷凍サイクルを構成する室内側熱交換器１および室内空気を送風するファン（図示せず）を搭載した、一般的なものでよく、図３に示すマルチタイプ用室内機４０のように冷媒の過熱度制御等に対応した温度検出手段である液管温度検知センサ４とガス管温度検知センサ５や絞り装置（電動膨張弁）６を搭載している必要はない。
【００１３】
次に冷媒中継ユニット２０について説明する。冷媒中継ユニット２０は、電動膨張弁２４と第１、第２配管温度センサ２３、２２から構成されており、冷房運転時に配管温度センサ２２は蒸発温度を検知し、配管温度センサ２３は冷媒乾き度を検知するものである。電動膨張弁２４は、室外機と室内機を接続する配管のうち液ライン側に設けられている。図１に示すように、電動膨張弁２４と第１、第２配管温度センサ２３、２２の全てが同一の筐体つまり１つの箱体に収納される構成となっている。また、冷媒中継ユニット２０内の液ライン側には電動膨張弁２４が、ガスライン側には第１配管温度センサである乾き度検知用配管温度センサ２３が設けられるとともに、液ライン側に設けられた電動膨張弁２４の冷房入口側とガスライン側に設けられた乾き度検知用配管温度センサ２３の冷房出口側（室外機側）との間に毛細管などの減圧機構を介した蒸発温度検出バイパス回路２５を設け、そのガスライン側出口部に第２配管温度センサである蒸発温度検知用配管温度センサ２２を搭載している。
【００１４】
これらの第１、第２配管温度センサ２３，２２により検出された検出温度は冷媒中継ユニット２０に搭載した中継ユニット制御装置２１から室外機の制御装置１１に送信され、室外機の制御装置１１にて適性な膨張弁開度を算出し、算出結果の膨張弁開度指令値を中継ユニット制御装置２１に返信して、電動膨張弁２４に弁開度を指令する。このように、中継ユニット制御装置２１は室外機制御装置１１および室内機制御装置３１と相互に伝送線を介してデータ送信を行う構成となっている。そして、冷媒中継ユニットを上述のように構成することにより、室内機と室外機の間を接続する冷媒延長配管の配管長さに係わらず、運転している室内機の空調負荷に応じた電動膨張弁の開度制御を行ない、適正な冷媒運転制御が可能となり快適性が向上するとともに、露飛び等の発生を抑制して信頼性の高い空調システムを得ることができる。
【００１５】
なお、冷媒中継ユニット２０に内設された乾き度検知用配管温度センサ２３および蒸発温度検知用配管温度センサ２２により検出された温度データ情報を、室外機側へ送信することなく中継ユニット制御装置２１自体にて膨張弁開度を演算し、電動膨張弁２４に弁開度指令してもよい。
【００１６】
また、図６に示すように、本発明の冷媒中継ユニット２０と１：１用室内機３０の組合せと、マルチ用室内機４０とが混在して室外機１０に接続されたシステムにおいても、１：１用室内機３０の空調負荷に応じて膨張弁制御を行なえ適性な空調運転ができるので、被空調状況に応じて空調システムの選択範囲が広くなる効果がある。
【００１７】
また、図７に示すように、図１に示した蒸発温度検出バイパス回路２５において、蒸発温度検知用配管温度センサ２２より出口側配管部分を二重管熱交換器２８として高圧側冷媒、例えば冷媒中継ユニットの液ライン側に設けた膨張弁の冷房入口側と、蒸発温度検知用バイパス回路２５の減圧機構を流通して蒸発温度検知用配管温度センサ２２を通過後の冷媒とを熱交換させることにより、蒸発温度検出バイパス回路２５を流れる冷媒を加熱してガス化させることで、蒸発温度の検出特性を損なうことなく冷媒のバイパス量を少なくすることが可能である。これにより、冷媒バイパスによる空調能力ロスを低減できる効果がある。
【００１８】
実施の形態２．
次に、本発明の実施の形態２による空気調和機の冷媒中継ユニットについて説明する。
図８は本発明の実施の形態２に係る空気調和機のシステムの冷媒回路図であり、図１と同一または相当部分は同一符号を付け、その説明は省略する。図において、冷媒中継ユニット２０内には液ライン側配管に設けた電動膨張弁２４、ガスライン側配管に設けた乾き度検知用配管温度センサ２３、および検知した温度データや運転指令等の情報を処理して伝送する中継ユニット制御装置２１が搭載されている。そして、室外機１０においての図１との差違は、室外熱交換器から冷媒中継ユニットへ接続する配管と冷媒中継ユニットから室外機の圧縮機側に接続された配管との間を接続して冷媒をバイパスさせる減圧機構を介したバイパス回路に設けられた蒸発温度検知用配管温度センサ１２を備えた点である。
【００１９】
上述のように実施の形態１で冷媒中継ユニット２０に内設していた蒸発温度検知用配管温度センサ１２を室外機１０側に搭載させ、検知した蒸発温度のデータを室外機制御装置１１から中継ユニット制御装置２１へ送信する構成とすることにより、冷媒中継ユニット２０の外部から蒸発温度を入手する手段を設けても良く、同様に室内機毎の空調負荷に対応した冷媒流量の調整が可能となる。さらに、図１の構成に比べて、冷媒中継ユニット内部に蒸発温度検出バイパス回路が不要となるため、冷媒中継ユニットの構成が簡単となり組み立て性の改善が図れる。
【００２０】
実施の形態３．
次に、本発明の実施の形態３による空気調和機の冷媒中継ユニットについて説明する。
図９は本発明の実施の形態３に係る空気調和機のシステムの冷媒回路図であり、図１と同一または相当部分は同一符号を付け、その説明は省略する。図において、冷媒中継ユニット２０は液ライン側配管に設けられた電子膨張弁２４と液ライン側配管のみ、もしくはガスライン側配管をも含むように収納した筐体から構成されている。
【００２１】
また、蒸発温度検知用配管温度センサ２２は上記電動膨張弁２４を収納する筐体から分離した蒸発温度検知センサ収納ボックス２６内に収納し、室内機の冷房入口部配管などの蒸発温度が検出できる位置に取り付け、一方乾き度検知用配管温度センサ２３も分離してガス管温度検知センサ収納ボックス２７内に収納し、室外機の冷房出口部配管などの冷媒乾き度が検知できる位置に取り付けて、各センサから信号を送信する伝送線を中継ユニット制御装置２１まで伸ばして接続することにより冷媒中継ユニット２０側で温度検知の処理できるように構成する。
【００２２】
上述の図９に示す実施の形態３では、冷媒中継ユニットが電動膨張弁のみで構成され、すなわち液ライン側のみ冷媒中継ユニットに含まれる形態が可能となり、図１や図８に示すようなガスライン側配管を冷媒中継ユニットから除くことができるので、この冷媒中継ユニットを小型化にできるとともに、設置スペースの制約条件も小さくなって取り付け自由度が広がる効果がある。
【００２３】
【発明の効果】
以上説明したとおり、本発明の空気調和機の冷媒中継ユニットは、室内熱交換器を有した室内機と少なくとも圧縮機および室外熱交換器を有した室外機とを延長配管を介して冷媒を循環させる空気調和機の冷媒中継ユニットにおいて、前記延長配管の液側配管に設けて冷媒を減圧する減圧装置と前記室内熱交換器の冷媒過熱度を検知する過熱度検知手段を備えたので、１：１タイプ用室内機をマルチタイプ用室外機に接続可能とすることができ、室内機側の仕様の共通化が図れる。
【００２４】
また、本発明の空気調和機の冷媒中継ユニットは、過熱度検知手段がガス側配管に設けられた第１配管温度センサおよび液側配管とガス側配管を減圧機構を介して接続するバイパス回路に設けられた第２配管温度センサからなるので、室内機と冷媒中継ユニットの距離が大きくなっても確実に冷媒過熱度コントロールが可能となり、冷媒中継ユニットの設置自由度がアップする効果が得られる。
【００２５】
また、本発明の空気調和機の冷媒中継ユニットは、減圧手段を収納した筐体に、室外機に設けた室外機制御装置および室内機に設けた室内機制御装置と相互に運転情報を伝送できる中継ユニット制御装置を備えたので、１：１タイプ用室内機をマルチタイプ用室外機に接続可能とすることができ、室内機側の仕様の共通化が図れる。
【図面の簡単な説明】
【図１】本発明の実施の形態１に係わる空気調和機の冷媒中継ユニットを用いたシステムの冷媒回路図である。
【図２】本発明の実施の形態１に係わり１：１タイプ用室内機の冷媒回路図である。
【図３】本発明の実施の形態１に係わりマルチタイプ用室内機の冷媒回路図である。
【図４】本発明の実施の形態１に係わる過熱度制御を示すフローチャート図である。
【図５】本発明の実施の形態１に係わる過熱度制御の膨張弁開度補正量を示す図である。
【図６】本発明の実施の形態１に係わり空気調和機の冷媒中継ユニットを用いた他のシステムの冷媒回路図である。
【図７】本発明の実施の形態１に係わり空気調和機の他の冷媒中継ユニットを用いたシステムの冷媒回路図である。
【図８】本発明の実施の形態２に係わる空気調和機の冷媒中継ユニットを用いたシステムの冷媒回路図である。
【図９】本発明の実施の形態３に係わる空気調和機の冷媒中継ユニットを用いたシステムの冷媒回路図である。
【符号の説明】
１１：１タイプ用室内機熱交換器、２室内機配管温度センサ、３マルチタイプ用室内機熱交換器、４液管温度検知センサ（蒸発温度検知用）、５ガス管温度検知センサ、６電動膨張弁、１０室外機、１１室外機制御装置、１２室外機蒸発温度検知センサ、２０冷媒中継ユニット、２１中継ユニット制御装置、２２蒸発温度検知用配管温度センサ、２３乾き度検知用配管温度センサ、２４電動膨張弁、２５蒸発温度検知用バイパス回路、２６液管温度検知センサ収納ボックス、２７ガス管温度検知センサ収納ボックス、２８二重管熱交換器、３０１：１タイプ室内機、３１１：１タイプ室内機制御装置、４０マルチタイプ室内機、４１マルチタイプ室内機制御装置。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a refrigerant relay unit of an air conditioner that is provided in a refrigerant pipe connecting an indoor unit and an outdoor unit of an air conditioner and distributes refrigerant from one outdoor unit to one or more indoor units. is there.
[0002]
[Prior art]
Conventionally, an indoor unit in a multi-type air conditioner in which one outdoor unit and a plurality of indoor units are connected to each other includes a heat exchanger, an electric expansion valve that adjusts and shuts off the refrigerant circulation amount, and a heat exchanger. In order to detect the degree of superheat or the degree of supercooling, pipe temperature sensors are attached before and after the heat exchanger, and the opening degree of the electric expansion valve is controlled based on the detected temperature information. If such an indoor unit is used, the indoor unit and the outdoor unit are connected without using a refrigerant distribution mechanism (such as a header) for diverting the refrigerant necessary for each indoor unit connected on the outdoor unit side. The refrigerant may be distributed at an arbitrary position in the extension pipe.
[0003]
On the other hand, an indoor unit in a 1: 1 type air conditioner in which one indoor unit is connected to one outdoor unit does not need to adjust the refrigerant circulation amount or shut off the refrigerant for each indoor unit. There is no electric expansion valve on the machine side. For this reason, the number of pipe temperature sensors provided on the indoor unit side and the installation positions are generally different from those of multi-type indoor units. Therefore, when connecting a 1: 1 type indoor unit to a multi-type outdoor unit, it is necessary to provide an electric expansion valve and a pipe temperature sensor for controlling the opening degree thereof outside the indoor unit. A relay unit with these built-in was provided between the outdoor units.
[0004]
In the conventional relay unit, the liquid pipe and the gas pipe are connected from the outdoor unit and the indoor unit, and the liquid pipe on the outdoor unit side and the liquid pipe on the indoor unit side are connected via a gas-liquid heat exchange unit. An electric expansion valve is provided for decompressing the refrigerant and distributing the refrigerant during heating. Further, a gas pipe thermistor for detecting the refrigerant temperature is provided in the gas pipe on the indoor unit side of the refrigerant relay unit. (For example, see Patent Document 1)
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-241697 (pages 3 to 4, FIGS. 1 and 2)
[0006]
[Problems to be solved by the invention]
However, in the refrigerant circuit configuration using the conventional refrigerant relay unit, when the distance between the indoor unit (indoor heat exchanger) and the electric expansion valve provided in the relay unit varies greatly depending on the installation conditions, for example, the distance may increase. If it becomes smaller, the refrigerant flow changes due to the pressure loss in the piping between the extension pipe between the indoor unit and the relay unit, and the temperature detected by the temperature sensor greatly affects the cooling inlet side for multi-type indoor units. The detection accuracy of the evaporating temperature of the refrigerant detected in (1) also varies depending on the pipe length. As a result, the actual degree of superheat of the evaporator cannot be accurately grasped, and there is a problem that the cooling capacity is insufficient or the heat exchanger dries out due to drying.
[0007]
The present invention has been made to solve the above-described problem, and is a refrigerant for an air conditioner that can secure a necessary refrigerant flow rate according to the load of the indoor unit regardless of the length of the extension pipe connecting the indoor unit and the outdoor unit. The purpose is to provide a relay unit.
[0008]
[Means for Solving the Problems]
The refrigerant relay unit of the air conditioner of the present invention is an air conditioner that circulates refrigerant through an extension pipe between an indoor unit having an indoor heat exchanger and an outdoor unit having at least a compressor and an outdoor heat exchanger. The refrigerant relay unit includes a pressure reducing device that is provided in the liquid side pipe of the extension pipe and depressurizes the refrigerant, and a superheat degree detecting means that detects the degree of refrigerant superheat of the indoor heat exchanger.
[0009]
Further, the refrigerant relay unit of the air conditioner of the present invention is a first circuit temperature sensor in which the superheat degree detection means is provided in the gas side pipe, and a bypass circuit that connects the liquid side pipe and the gas side pipe via the pressure reducing mechanism. The second pipe temperature sensor is provided.
[0010]
In addition, the refrigerant relay unit of the air conditioner of the present invention can transmit operation information to the outdoor unit control device provided in the outdoor unit and the indoor unit control device provided in the indoor unit in a casing housing the decompression unit. A relay unit control device is provided.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Hereinafter, the refrigerant relay unit of the air conditioner according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 7.
FIG. 1 is a refrigerant circuit diagram showing an air conditioner system according to the present embodiment. In the figure, this air conditioner is composed of one outdoor unit 10, one or a plurality of indoor units 30, and a refrigerant relay unit 20 corresponding to the number of indoor units. The outdoor unit 10 includes a compressor, an accumulator, an outdoor heat exchanger, and a fan that blows outside air to the heat exchanger in order to exchange heat between the outdoor air and the refrigerant. It is installed. In addition, an outdoor unit control device 11 for controlling the entire system of the air conditioner is also mounted, and the opening control of the electric expansion valve for adjusting the compressor operating frequency and the refrigerant throttle amount according to the air conditioning load. I do.
[0012]
As shown in FIG. 4, the opening degree control of the electric expansion valve performs an opening degree command for adjusting the outlet side refrigerant superheat degree of each indoor heat exchanger to a predetermined target value during cooling. For example, the difference between the detected temperatures of the evaporation temperature detection sensor provided in the evaporation side heat exchanger and the gas pipe temperature detection sensor provided in the pipe connected to the outlet side of the evaporator is defined as the degree of superheat (SH) of the indoor unit. Since the superheat degree SH changes depending on the air conditioning load and the refrigerant flow rate on the indoor unit side, it is determined whether or not the measured superheat degree is a predetermined target superheat degree SHm (for example, 3 deg). If the target degree of superheat is not reached, the correction amount ΔLj is added to the opening Lj corresponding to the expansion valve opening determined in advance according to ΔSH (= SH−SHm). Since this calculation is performed by the control unit of the outdoor unit, the control unit of the outdoor unit obtains the temperature information detected by each temperature sensor (temperature detection means) by communication and indicates the refrigerant state of the refrigeration cycle. The expansion valve command opening is calculated on the basis of the temperature information, the calculation result is returned from the outdoor unit control device to the relay unit control device, and the opening is commanded to the electric expansion valve. FIG. 5 shows the electric expansion valve opening correction amount ΔLj according to ΔSH.
Moreover, the indoor unit is equipped with an indoor side heat exchanger 1 that constitutes a refrigeration cycle and a fan (not shown) that blows indoor air, as in the 1: 1 type indoor unit 30 shown in FIG. As in the multi-type indoor unit 40 shown in FIG. 3, the liquid pipe temperature detection sensor 4 and the gas pipe temperature detection sensor 5 which are temperature detection means corresponding to the superheat degree control of the refrigerant and the throttle device (electrically driven) (Expansion valve) 6 need not be mounted.
[0013]
Next, the refrigerant relay unit 20 will be described. The refrigerant relay unit 20 includes an electric expansion valve 24 and first and second pipe temperature sensors 23, 22. The pipe temperature sensor 22 detects the evaporation temperature during the cooling operation, and the pipe temperature sensor 23 indicates the degree of refrigerant dryness. Is detected. The electric expansion valve 24 is provided on the liquid line side in the pipe connecting the outdoor unit and the indoor unit. As shown in FIG. 1, the electric expansion valve 24 and the first and second pipe temperature sensors 23 and 22 are all housed in the same casing, that is, one box. An electric expansion valve 24 is provided on the liquid line side in the refrigerant relay unit 20, and a dryness detection pipe temperature sensor 23, which is a first pipe temperature sensor, is provided on the gas line side, and provided on the liquid line side. Evaporation temperature detection bypass through a pressure reducing mechanism such as a capillary between the cooling inlet side of the electric expansion valve 24 and the cooling outlet side (outdoor unit side) of the dryness detection pipe temperature sensor 23 provided on the gas line side. A circuit 25 is provided, and an evaporating temperature detecting pipe temperature sensor 22 as a second pipe temperature sensor is mounted on the gas line side outlet portion.
[0014]
The detected temperatures detected by the first and second pipe temperature sensors 23 and 22 are transmitted from the relay unit control device 21 mounted on the refrigerant relay unit 20 to the control device 11 of the outdoor unit, and are transmitted to the control unit 11 of the outdoor unit. Appropriate expansion valve opening is calculated, the expansion valve opening command value of the calculated result is returned to the relay unit control device 21, and the valve opening is commanded to the electric expansion valve 24. Thus, the relay unit control device 21 is configured to transmit data to the outdoor unit control device 11 and the indoor unit control device 31 via the transmission line. By configuring the refrigerant relay unit as described above, the electric expansion according to the air conditioning load of the operating indoor unit regardless of the length of the refrigerant extension pipe connecting the indoor unit and the outdoor unit. By controlling the opening of the valve, it is possible to perform appropriate refrigerant operation control and improve comfort, and it is possible to obtain a highly reliable air-conditioning system by suppressing occurrence of dewdrops and the like.
[0015]
The relay unit control device 21 does not transmit the temperature data information detected by the dryness detection pipe temperature sensor 23 and the evaporation temperature detection pipe temperature sensor 22 provided in the refrigerant relay unit 20 to the outdoor unit side. The opening degree of the expansion valve may be calculated by itself, and the opening degree of the electric expansion valve 24 may be commanded.
[0016]
Further, as shown in FIG. 6, in a system in which the combination of the refrigerant relay unit 20 of the present invention and the 1: 1 indoor unit 30 and the multi-unit indoor unit 40 are mixedly connected to the outdoor unit 10, Since the expansion valve control can be performed according to the air conditioning load of the indoor unit 30 for 1 and appropriate air conditioning operation can be performed, there is an effect that the selection range of the air conditioning system is widened according to the air-conditioned condition.
[0017]
Further, as shown in FIG. 7, in the evaporation temperature detection bypass circuit 25 shown in FIG. 1, a high-pressure side refrigerant, for example, a refrigerant, with the outlet side pipe portion as the double pipe heat exchanger 28 from the evaporation temperature detection pipe temperature sensor 22 is used. Heat exchange is performed between the cooling inlet side of the expansion valve provided on the liquid line side of the relay unit and the refrigerant after passing through the pressure reducing mechanism of the evaporation temperature detection bypass circuit 25 and passing through the evaporation temperature detection pipe temperature sensor 22. Thus, by heating and gasifying the refrigerant flowing through the evaporation temperature detection bypass circuit 25, the bypass amount of the refrigerant can be reduced without impairing the detection characteristics of the evaporation temperature. Thereby, there exists an effect which can reduce the air-conditioning capability loss by a refrigerant bypass.
[0018]
Embodiment 2. FIG.
Next, a refrigerant relay unit of an air conditioner according to Embodiment 2 of the present invention will be described.
FIG. 8 is a refrigerant circuit diagram of the air conditioner system according to Embodiment 2 of the present invention. The same or corresponding parts as those in FIG. In the figure, the refrigerant relay unit 20 includes an electric expansion valve 24 provided on the liquid line side pipe, a dryness detection pipe temperature sensor 23 provided on the gas line side pipe, and information such as detected temperature data and operation commands. A relay unit control device 21 for processing and transmitting is mounted. The difference between the outdoor unit 10 and FIG. 1 is that the pipe connecting the outdoor heat exchanger to the refrigerant relay unit and the pipe connected from the refrigerant relay unit to the compressor side of the outdoor unit are connected to each other. It is the point provided with the piping temperature sensor 12 for evaporating temperature detection provided in the bypass circuit via the pressure reduction mechanism which bypasses.
[0019]
As described above, the evaporating temperature detection pipe temperature sensor 12 provided in the refrigerant relay unit 20 in the first embodiment is mounted on the outdoor unit 10 side, and the detected evaporation temperature data is relayed from the outdoor unit control device 11. With the configuration of transmitting to the unit control device 21, a means for obtaining the evaporation temperature from the outside of the refrigerant relay unit 20 may be provided, and similarly, the refrigerant flow rate corresponding to the air conditioning load for each indoor unit can be adjusted. Become. Further, as compared with the configuration of FIG. 1, the evaporating temperature detection bypass circuit is not required inside the refrigerant relay unit, so that the configuration of the refrigerant relay unit is simplified and the assemblability can be improved.
[0020]
Embodiment 3 FIG.
Next, a refrigerant relay unit of an air conditioner according to Embodiment 3 of the present invention will be described.
FIG. 9 is a refrigerant circuit diagram of an air conditioner system according to Embodiment 3 of the present invention. The same or corresponding parts as those in FIG. In the figure, the refrigerant relay unit 20 is composed of a housing housed so as to include only the electronic expansion valve 24 and the liquid line side pipe provided in the liquid line side pipe or the gas line side pipe.
[0021]
Further, the evaporating temperature detecting pipe temperature sensor 22 is housed in an evaporating temperature detecting sensor storage box 26 separated from the housing for storing the electric expansion valve 24, and can detect the evaporating temperature of the cooling inlet pipe of the indoor unit. At the same time, the pipe temperature sensor for dryness detection 23 is also separated and stored in the gas pipe temperature detection sensor storage box 27, and attached to a position where the dryness of the refrigerant such as the cooling outlet pipe of the outdoor unit can be detected, A transmission line for transmitting a signal from each sensor is extended to and connected to the relay unit control device 21 so that the temperature detection processing can be performed on the refrigerant relay unit 20 side.
[0022]
In the third embodiment shown in FIG. 9 described above, the refrigerant relay unit is configured only by the electric expansion valve, that is, only the liquid line side is included in the refrigerant relay unit, and the gas as shown in FIG. 1 or FIG. Since the line-side piping can be removed from the refrigerant relay unit, the refrigerant relay unit can be reduced in size and the installation space can be reduced, and the degree of freedom of installation can be increased.
[0023]
【The invention's effect】
As described above, the refrigerant relay unit of the air conditioner of the present invention circulates the refrigerant through the extension pipe between the indoor unit having the indoor heat exchanger and the outdoor unit having at least the compressor and the outdoor heat exchanger. In the refrigerant relay unit of the air conditioner to be provided with the depressurization device for depressurizing the refrigerant provided in the liquid side pipe of the extension pipe and the superheat degree detecting means for detecting the refrigerant superheat degree of the indoor heat exchanger, The indoor unit for one type can be connected to the outdoor unit for multi-type, and the specifications on the indoor unit side can be shared.
[0024]
Further, the refrigerant relay unit of the air conditioner of the present invention is a first circuit temperature sensor in which the superheat degree detection means is provided in the gas side pipe, and a bypass circuit that connects the liquid side pipe and the gas side pipe via the pressure reducing mechanism. Since the second pipe temperature sensor is provided, the refrigerant superheat degree can be reliably controlled even when the distance between the indoor unit and the refrigerant relay unit is increased, and the effect of increasing the degree of freedom in installing the refrigerant relay unit can be obtained.
[0025]
In addition, the refrigerant relay unit of the air conditioner of the present invention can transmit operation information to the outdoor unit control device provided in the outdoor unit and the indoor unit control device provided in the indoor unit in a casing housing the decompression unit. Since the relay unit controller is provided, the 1: 1 type indoor unit can be connected to the multi-type outdoor unit, and the specifications on the indoor unit side can be shared.
[Brief description of the drawings]
FIG. 1 is a refrigerant circuit diagram of a system using a refrigerant relay unit of an air conditioner according to Embodiment 1 of the present invention.
FIG. 2 is a refrigerant circuit diagram of a 1: 1 type indoor unit according to the first embodiment of the present invention.
FIG. 3 is a refrigerant circuit diagram of the multi-type indoor unit according to the first embodiment of the present invention.
FIG. 4 is a flowchart showing superheat degree control according to the first embodiment of the present invention.
FIG. 5 is a diagram showing an expansion valve opening correction amount for superheat degree control according to the first embodiment of the present invention.
FIG. 6 is a refrigerant circuit diagram of another system using the refrigerant relay unit of the air conditioner according to the first embodiment of the present invention.
FIG. 7 is a refrigerant circuit diagram of a system according to Embodiment 1 of the present invention and using another refrigerant relay unit of the air conditioner.
FIG. 8 is a refrigerant circuit diagram of a system using a refrigerant relay unit of an air conditioner according to Embodiment 2 of the present invention.
FIG. 9 is a refrigerant circuit diagram of a system using a refrigerant relay unit of an air conditioner according to Embodiment 3 of the present invention.
[Explanation of symbols]
1 1: 1 type indoor unit heat exchanger, 2 indoor unit piping temperature sensor, 3 multi-type indoor unit heat exchanger, 4 liquid pipe temperature detection sensor (for evaporating temperature detection), 5 gas pipe temperature detection sensor, 6 Electric expansion valve, 10 outdoor unit, 11 outdoor unit control device, 12 outdoor unit evaporating temperature detection sensor, 20 refrigerant relay unit, 21 relay unit control unit, 22 evaporating temperature detecting pipe temperature sensor, 23 dryness detecting pipe temperature sensor 24 Electric expansion valve, 25 Evaporation temperature detection bypass circuit, 26 Liquid pipe temperature detection sensor storage box, 27 Gas pipe temperature detection sensor storage box, 28 Double pipe heat exchanger, 30 1: 1 type indoor unit, 31 1 1 type indoor unit control device, 40 multi type indoor unit, 41 multi type indoor unit control device.

Claims

In a refrigerant relay unit of an air conditioner that circulates a refrigerant through an extension pipe between an indoor unit having an indoor heat exchanger and at least an outdoor unit having a compressor and an outdoor heat exchanger, the liquid side pipe of the extension pipe A refrigerant relay unit for an air conditioner, comprising: a pressure reducing device that depressurizes the refrigerant and a superheat degree detecting unit that detects a refrigerant superheat degree of the indoor heat exchanger.

The refrigerant relay unit for an air conditioner according to claim 1, wherein the decompression device and the superheat detection means are housed in the same casing.

The superheat degree detecting means includes a first pipe temperature sensor provided in the gas side pipe and a second pipe temperature sensor provided in a bypass circuit connecting the liquid side pipe and the gas side pipe through a pressure reducing mechanism. The refrigerant relay unit for an air conditioner according to claim 1 or 2.

2. The refrigerant relay unit for an air conditioner according to claim 1, wherein the superheat degree detecting means is disposed separately from a housing housing the pressure reducing means.

5. The refrigerant relay unit of an air conditioner according to claim 4, wherein the superheat degree detection means is provided in a portion that can directly detect the superheat degree of the indoor unit heat exchanger.

The enclosure containing the decompression means includes an outdoor unit control device provided in the outdoor unit and a relay unit control device capable of transmitting operation information to and from the indoor unit control device provided in the indoor unit. The refrigerant relay unit of the air conditioner according to any one of claims 1 to 5.

The refrigerant relay unit of an air conditioner according to claim 6, wherein the relay unit control device controls the pressure reducing device based on the degree of superheat detected by the superheat degree detection means.