JP2760500B2

JP2760500B2 - Multi-room air conditioner

Info

Publication number: JP2760500B2
Application number: JP62324493A
Authority: JP
Inventors: 邦衛関上
Original assignee: Sanyo Denki Co Ltd
Current assignee: Sanyo Denki Co Ltd
Priority date: 1987-12-21
Filing date: 1987-12-21
Publication date: 1998-05-28
Anticipated expiration: 2013-05-28
Also published as: JPH01167561A

Description

【発明の詳細な説明】（イ）産業上の利用分野本発明は１台の室外ユニットと複数台の室内ユニット
とから構成され、複数室の全てを同時に冷房又は暖房
し、且つ同時に任意の室を冷房し他室を暖房する多室型
冷暖房装置に関する。（ロ）従来の技術複数室の全てを同時に冷房又は暖房でき、且つ同時に
複数室の一室を冷房し他室を暖房できる多室型冷暖房装
置が特公昭52−24710号公報、特公昭52−24711号公報、
実公昭54−3020号公報で提示されている。（ハ）発明が解決しようとする問題点上記の特公昭52−24710号公報及び特公昭52−24711号
公報で提示の装置では室内ユニットの数だけ四方切換弁
と室外熱交換器とを必要とするため配管回路構成が複雑
になると共に製造コストが高くつき、且つ各室内ユニッ
トごとに２本のユニット間配管を室外ユニットから引き
出さなければならないため、ユニット間配管の本数が多
くなり配管工事が面倒である欠点を有していた。しかも
同時に一室を冷房、他室を暖房する冷暖房運転時、各室
内ユニットと対応する室外熱交換器が凝縮器及び蒸発器
として夫々作用して屋外に熱を捨てており、熱回収でき
ない難点があった。又、上記の実公昭54−3020号公報で提示の装置では同
時に複数室の或る室を冷房し他室を暖房する冷暖房運転
時、冷房できる室と暖房できる室との組み合わせが決ま
っており、冷暖房運転を各室で自由に選択して行なうこ
とができず、使用勝手が悪い欠点を有していた。本発明は上述した問題点を解決すると共に、実用性の
高い多室型冷暖房装置を提供するものである。（ニ）問題点を解決するための手段本発明は、圧縮機と室外熱交換器とを有する室外ユニ
ットと、室内熱交換器を有る複数台の室内ユニットとを
備え、前記室外熱交換器を圧縮機の冷媒吐出管と冷媒吸
込管とに切換弁を介して分岐接続する一方、これら両室
内外ユニットをつなぐユニット間配管を前記冷媒吐出管
と分岐接続された高圧ガス管と、前記冷媒吸込管と分岐
接続された低圧ガス管と、前記室外熱交換器と接続され
た液管とで構成し、前記各室内熱交換器を前記高圧ガス
管と低圧ガス管とには切換弁を介して分岐接続すると共
に、前記液管には冷媒減圧器を介して接続した多室型冷
暖房装置において、前記高圧ガス管内の冷媒の溜まり込
みを防止するためのバイパス管でこの高圧ガス管とこの
高圧ガス管よりも冷媒圧力が低くなるユニット間配管と
をつないだことを特徴とする。（ホ）作用全室を同時に冷房する場合は、室外熱交換器の切換弁
と各室内熱交換器の切換弁とを冷房状態に設定すること
により、圧縮機から吐出された冷媒は吐出管より室外熱
交換器に流れてここで凝縮液化した後、、液管を経て各
室内ユニットの冷媒減圧器に分配され、然る後、各室内
熱交換器で蒸発気化した後、低圧ガス管と冷媒吸込管と
を順次経て圧縮機に吸入される。このように蒸発器とし
て作用する各室内熱交換器で全室が冷房される。又、全室を同時に暖房する場合は、室外熱交換器の切
換弁と各室内熱交換器の切換弁とを暖房状態に設定する
ことにより、圧縮機から吐出された冷媒は吐出管と高圧
ガス管とを順次経て各室内熱交換器に分配されここで夫
々凝縮液化した後、各冷媒減圧器を経て液管で合流さ
れ、然る後、室外熱交換器で蒸発気化した後、冷媒吸込
管を経て圧縮機に吸入される。このように凝縮器として
作用する各室内熱交換器で全室が暖房される。又、同時に任意の例えば二室を冷房し一室を暖房する
場合は、室外熱交換器の切換弁を暖房状態に設定すると
共に冷房する室内ユニットの室内熱交換器の切換弁を冷
房状態に設定し、且つ暖房する室内ユニットの室内熱交
換器の切換弁を暖房状態に設定すると、圧縮機から吐出
された冷媒の一部が室外熱交換器に流れると共に残りの
冷媒が高圧ガス管を経て暖房する室内ユニットの室内熱
交換器へ流れこの室内熱交換器と室外熱交換器とで凝縮
液化される。そしてこれら熱交換器で凝縮液化された冷
媒は液管を経て各室内ユニットの冷媒減圧器に分配され
た後、各室内熱交換器で蒸発気化し、然る後、低圧ガス
管を冷媒吸込管とを順次経て圧縮機に吸入される。この
ように凝縮器として作用する室内熱交換器で一室が暖房
され、蒸発器として作用する他の室内熱交換器で二室が
冷房される。そして、バイパス管を介して、高圧ガス管内の冷媒は
この高圧ガス管よりも冷媒圧力が低くなるユニット間配
管に導かれる。（ヘ）実施例本発明の第１実施例を第１図に基づいて説明すると、
（１）は圧縮機（２）と室外熱交換器（３）と気液分離
器（４）とを有する室外ユニット、（5a）（5b）（5c）
は室内熱交換器（6a）（6b）（6c）を有する室内ユニッ
トで、室外熱交換器（３）を圧縮機（２）の冷媒吐出管
（７）と冷媒吸込管（８）とに切換弁（9a）（9b）を介
して分岐接続する一方、室外ユニット（１）と室内ユニ
ット（5a）（5b）（5c）とを接続するユニット間配管
（10）を冷媒吐出管（７）と分岐接続された高圧ガス管
（11）と、冷媒吸込管（８）と分岐接続された低圧ガス
管（12）と、室外熱交換器（３）と接続された液管（1
3）とで構成して、各室内熱交換器（6a）（6b）（6c）
を高圧ガス管（11）と低圧ガス管（12）とには夫々切換
弁（14a）（15a），（14b）（15b），（14c）（15c）を
介して分岐接続すると共に液管（13）には電動式膨張弁
等の冷媒減圧器（16a）（16b）（16c）を介して接続し
ている。（17）は高圧ガス管（11）と低圧ガス管（12）とを接
続したバイパス管で、毛細管（18）で冷媒絞り抵抗をも
たしている。（19）は低圧ガス管（12）に介在させた蒸発圧力調整
弁、（20）は液管（13）に介在させた電動式膨張弁等の
補助冷媒減圧器である。次に運転動作を説明する。全室を同時に冷房する場合
は、室外熱交換器（３）の一方の切換弁（9a）を開くと
共に他方の切換弁（9b）を閉じ、且つ室内熱交換器（6
a）（6b）（6c）の一方の切換弁（14a）（14b）（14c）
を閉じると共に他方の切換弁（15a）（15b）（15c）を
開くことにより、圧縮機（２）から吐出された冷媒は吐
出管（７）、切換弁（9a）、室外熱交換器（３）と順次
流れてここで凝縮液化した後、液管（13）を経て各室内
ユニット（5a）（5b）（5c）の冷媒減圧器（16a）（16
b）（16c）に分配され、ここで減圧される。然る後、各
室内熱交換器（6a）（6b）（6c）で蒸発気化した後、夫
々切換弁（15a）（15b）（15c）、低圧ガス管（12）、
吸込管（８）、気液分離器（４）を順次経て圧縮機
（２）に吸入される。このように蒸発器として作用する
各室内熱交換器（6a）（6b）（6c）で全室が同時に冷房
される。かかる同時冷房運転時、圧縮機（２）から吐出された
冷媒が高圧ガス管（11）よりバイパス管（17）を経て低
圧ガス管（12）に導かれるので、高圧ガス管（11）に冷
媒が溜まり込むことはない。逆に全室を同時に暖房する場合は、室外熱交換器
（３）の一方の切換弁（9a）を閉じると共に他方の切換
弁（9b）を開き、且つ室内熱交換器（6a）（6b）（6c）
の一方の切換弁（14a）（14b）（14c）を開くと共に他
方の切換弁（15a）（15b）（15c）を閉じることによ
り、圧縮機（２）から吐出された冷媒は吐出管（７）、
高圧ガス管（11）を順次経て切換弁（14a）（14b）（14
c）、室内熱交換器（6a）（6b）（6c）へと分配され、
ここで夫々凝縮液化した後、各冷媒減圧器（16a）（16
b）（16c）で減圧されて液管（13）で合流され、然る
後、室外熱交換器（３）で蒸発気化した後、切換弁（9
b）、吸込管（８）、気液分離器（４）を順次経て圧縮
機（２）に吸入される。このように凝縮器として作用す
る各室内熱交換器（6a）（6b）（6c）で全室が同時に暖
房される。又、同時に任意の例えば二室を冷房し一室を暖房する
場合は、室外熱交換器（３）の一方の切換弁（9a）を開
くと共に他方の切換弁（9b）を閉じ、且つ、冷房する室
内ユニット（5a）（5c）の一方の切換弁（14a）（14c）
を閉じると共に他方の切換弁（15a）（15c）を開き、且
つ暖房する室内ユニット（5b）の一方の切換弁（14b）
を開くと共に他方の切換弁（15b）を閉じると、圧縮機
（２）から吐出された冷媒の一部が吐出管（７）、切換
弁（９）ａを順次経て室外熱交換器（３）に流れると共
に残りの冷媒が高圧ガス管（11）を経て暖房する室内ユ
ニット（5b）の切換弁（14b）、室内熱交換器（6b）へ
と流れ、この室内熱交換器（6b）と室外熱交換器（３）
とで凝縮液化される。そして、これら熱交換器（6b）
（３）で凝縮液化された冷媒は液管（13）を経て室内ユ
ニット（5a）（5c）の冷媒減圧器（16a）（16c）で減圧
された後、夫々の室内熱交換器（6a）（6c）で蒸発気化
され、然る後、各切換弁（15a）（15c）を経て低圧ガス
管（12）で合流され、吸込管（８）、気液分離器（４）
を順次経て圧縮機（２）に吸入される。このように凝縮
器として作用する室内熱交換器（6b）で一室が暖房さ
れ、蒸発器として作用する他の室内熱交換器（6a）（6
c）で二室が冷房される。かかる冷暖房同時運転時、室内ユニット（5b）の冷媒
減圧器（16b）が全開して冷媒圧力損失が生じないよう
にしているが、液管（13）内の液冷媒圧力がアンバラン
スにならないように補助冷媒減圧器（20）で圧力調整さ
れている。又、かかる冷暖房同時運転が冬期に行なわれると低圧
冷媒圧力が外気温によって左右されるため冷房している
室内ユニット（5a）（5c）の室内熱交換器（6a）（6c）
内の冷媒圧力が4kg/cm²以下に低下し易くなる。このた
め、圧力低下（4kg/cm²以下）が生じると、蒸発圧力調
整弁（19）を絞りぎみとして、この圧力低下を防止す
る。言い換えれば、この蒸発圧力調整弁（19）の絞り動
作によって、室内熱交換器（6a）（6b）内の冷媒圧力を
所定値以上に保つようにしたので、室内熱交換器（6a）
（6b）が凍結することはない。尚、蒸発圧力調整弁（1
9）は低圧ガス管（12）に設ける代わりに、各切換弁（1
5a）（15b）（15c）と低圧ガス管（12）との間すなわち
低圧ガス管（12）の流入側の管（21a）（21b）（21c）
に夫々設けてもよい。又、蒸発圧力調整弁（19）を設け
る代わりに室内熱交換器（6a）（6c）内の冷媒圧力が4k
g/cm²以下に低下した時は冷媒減圧器（16a）（16c）の
開度を絞り、凍結が解除されると冷媒減圧器（16a）（1
6c）の開度を元に戻すようにしても良い。又、かかる冷暖房同時運転時、室外熱交換器（３）を
冷却する室外ファン（22）の回転数を、全室同時暖房運
転における室外ファン（22）の回転数よりも下げて、冷
媒の高圧圧力の低下を防止するため、全室同時暖房運転
の暖房能力と比較して、室内ユニット（5b）の暖房能力
が低下することはない。このように各室内ユニット（5a）（5b）（5c）は夫々
の切換弁（14a）（15a），（14b）（15b），（14c）（1
5c）を開閉させることにより任意に冷暖房運転すること
が可能である。尚、一室を冷房し二室を暖房する場合は補助冷媒減圧
器（20）を作動させることにより可能である。例えば、室内ユニット（5b）で冷房し室内ユニット
（5a）（5c）で暖房する場合は室外熱交換器（３）の一
方の切換弁（9a）を閉じると共に他方の切換弁（9b）を
開き、且つ冷房する室内ユニット（5b）の一方の切換弁
（14b）を閉じると共に他方の切換弁（15b）を開き、且
つ暖房する室内ユニット（5a）（5c）の一方の切換弁
（14a）（14c）を開くと共に他方の切換弁（15a）（15
c）を閉じると圧縮機（２）から吐出された冷媒が吐出
管（７）、高圧ガス管（11）と順次経て切換弁（14a）
（14c）へと分配され夫々の室内熱交換器（6a）（6c）
で凝縮液化される。そしてこの液化された冷媒は夫々全
開された冷媒減圧器（16a）（16c）を経て液管（13）に
流れ、この液管中の液冷媒の一部が冷媒減圧器（16b）
で減圧された後に室内熱交換器（6b）で、且つ残りの液
冷媒が補助冷媒減圧器（20）で減圧された後に室外熱交
換器（３）で夫々蒸発気化され、吸込管（８）、気液分
離器（４）を順次経て圧縮機（２）に吸入される。この
ように凝縮器として作用する室内熱交換器（6a）（6c）
で二室が暖房され、蒸発器として作用する他の室内熱交
換器（6b）で一室が冷房される。かかる同時冷暖房運転時においても、圧縮機（２）か
ら吐出された高圧ガス冷媒の一部は室内ユニット（5c）
よりも反室内ユニット（5b）側（第１図においては室内
ユニット（5c）の右側）へ流れるものの、流れ込んだ高
圧ガス冷媒はバイパス管（17）を経てこの高圧ガス管
（11）よりも冷媒圧力が低くなるユニット間配管すなわ
ち低圧ガス管（12）に導かれるので、高圧ガス管（11）
に冷媒が溜まり込むことはない。このように、高圧ガス
管（11）を行き止まり状態にしていないので、高圧ガス
管（11）に冷媒が溜まり込むことを前提にこの装置に冷
媒をチャージする必要がなくなり、冷媒量の減少を図る
ことができる。以上の如く、冷房する室の数（冷房容量）が暖房する
室の数（暖房容量）よりも多い時は室外熱交換器（３）
を凝縮器として、逆に暖房する室の数（暖房容量）が冷
房する室の数（冷房容量）よりも少ない時は室外熱交換
器（３）を蒸発器として作用させることにより任意の室
を自由に冷暖房することができると共に、この同時冷暖
房運転時に蒸発器及び凝縮器として作用する夫々の室内
熱交換器で熱回収が行なわれ、運転効率を向上させるこ
とができる。又、上述の全室冷房運転中に例えば室内ユニット（5
b）のみを暖房運転に切換える場合、切換弁（14b）（15
b）の両方を閉じると共に冷媒減圧器（16b）の開度を開
きぎみにする。これによって、液管（13）内の冷媒が冷
媒減圧器（16b）を介して室内熱交換器（16b）に流れ込
むので、冷房運転によって低圧状態となっていた室内熱
交換器（16b）の冷媒圧力が上昇する。このようにした
ので、暖房運転開始に伴って、切換弁（14b）を開けて
も、冷媒圧力差による冷媒音の発生が防止される。同様に、全室暖房運転中に例えば室内ユニット（5b）
のみを冷房運転に切り換える場合、切換弁（14b）と冷
媒減圧器（16b）とを閉じると共に、切換弁（15b）を僅
かに開く。これによって、暖房運転によって高圧状態と
なっていた室内熱交換器（16b）の冷媒圧力は切換弁（1
5b）を介して低圧ガス管（12）に導かれ、この室内熱交
換器（5b）の冷媒圧力を強制的に低下させる。または、
切換弁（15b）も閉じて室内熱交換器（16b）内の冷媒圧
力を自然に低下させる。室内熱交換器（16b）内の冷媒
圧力を低下させた後、切換弁（15b）を開けば、冷媒圧
力差にによる冷媒音の発生が防止される。このように、室内ユニットを冷房運転から暖房運転、
もしくは暖房運転から冷房運転に切り換える際に、この
室内ユニットの室内熱交換器の冷媒圧力を、２つの切換
弁と冷媒減圧器とで調整するようにしたので、運転の切
り換えによって室内熱交換器からの冷媒音の発生が防止
される。尚、切換弁（15b）を僅か開かせるには切換弁（15b）
として開度調整可能な高価な電動弁を用いることになる
ため、切換弁（15b）及び他の切換弁（15a）（15c）と
並列に圧力逃がし用のバイパス用毛細管を設ければ、切
換弁（15a）（15b）（15c）として単なる開閉弁を用い
ることができる。第２図は本発明の第２実施例を示すもので、室内ユニ
ット（5c）が電算機室などの年間冷房室に設置される場
合は切換弁（14c）（15c）を用いずに、直接、室内熱交
換器（6c）を低圧ガス管（12）に接続したものである。第３図は本発明の第３実施例を示すもので、室内熱交
換器（6c）を年間暖房や給湯用として利用する場合は切
換弁（14c）（15c）を用いずに、直接、室内熱交換器
（6c）を高圧ガス管（11）に接続したものである。第４図は本発明の第４実施例を示すもので、各室内ユ
ニット（5a）（5b）（5c）内の配管を図示の如く接続し
て切換弁（14a）（15a），（14b）（15b），（14c）（1
5c）、及び冷媒減圧器（16a）（16b）（16c）、並びに
逆止弁（23a）（23b）（23c）を設けたものであり、冷
房時は液管（13）からの液冷媒が冷媒減圧器（16a）（1
6b）（16c）で減圧された後、室内熱交換器（6a）（6
b）（6c）−切換弁（15a）（15b）（15c）−低圧ガス管
（12）と流れ、暖房時は高圧ガス管（11）からのガス冷
媒が切換弁（14a）（14b）（14c）−室内熱交換器（6
a）（6b）（6c）−逆止弁（23a）（23b）（23c）−液管
（13）と流れるほかは上記第１実施例と同様である。第５図は本発明の第５実施例を示すもので、各室内熱
交換器（6a）（6b）（6c）を夫々第１熱交換器（61a）
（61b）（61c）と第２熱交換器（62a）（62b）（62c）
とに二分割してこの両熱交換器の間に電動式膨張弁等の
除湿用冷媒減圧器（24a）（24b）（24c）を設けたもの
であり、冷房時は液管（13）からの液冷媒が冷媒減圧器
（16a）（16b）（16c）で減圧された後、第１熱交換器
（61a）（61b）（61c）−全開状態の除湿用冷媒減圧器
（24a）（24b）（24c）−第２熱交換器（62a）（62b）
（62c）−切換弁（15a）（15b）（15c）と流れ、蒸発器
として作用する第1,第２熱交換器（61a）（62a），（61
b）（62b），（61c）（62c）で夫々冷房される。一方、
暖房時は高圧ガス管（11）からのガス冷媒が切換弁（14
a）（14b）（14c）−第２熱交換器（62a）（62b）（62
c）−全開状態の除湿用冷媒減圧器（24a）（24b）（24
c）−第１熱交換器（61a）（61b）（61c）−冷媒減圧器
（16a）（16b）（16c）−液管（13）と流れ、凝縮器と
して作用する第1,第２熱交換器（61a）（62a），（61
b）（62b），（61c）（62c）で夫々冷房される。又、除湿時は液管（13）からの液冷媒が全開状態の冷
媒減圧器（16a）（16b）（16c）−第１熱交換器（61a）
（61b）（61c）を経て除湿用冷媒減圧器（24a）（24b）
（24c）で減圧された後、第２熱交換器（62a）（62b）
（62c）−切換弁（15a）（15b）（15c）と流れ、蒸発器
として作用する第２熱交換器（62a）（62b）（62c）で
冷却された室内空気が凝縮器として作用する第１熱交換
器（61a）（61b）（61c）で再加熱されて除湿される。尚、上記各実施例では３台の室内ユニット（5a）（5
b）（5c）を用いたが、４台以上の多数の能力が異なる
室内ユニットの場合でも単にユニット間配管（10）と分
岐接続するだけで良く、しかも圧縮機（２）を周波数変
換型、極数変換型、アンローダ型などの能力可変型圧縮
機とすれば任意の室内ユニットの運転を休止させること
が可能である。（ト）発明の効果本発明は室外ユニットと複数台の室内ユニットを接続
するユニット間配管を、高圧ガス管と低圧ガス管と液管
との３本の冷媒管で構成したので、単一機能の室外熱交
換器を用いた簡易な回路構成のもとで、複数台の室内ユ
ニットの同時冷房運転及び同時暖房運転はもとより冷暖
房同時運転の任意の室内ユニットで自由に選択して行な
うことができる。そして、バイパス管を介して、高圧ガス管内の冷媒は
この高圧ガス管よりも冷媒圧力が低くなるユニット間配
管に導いて、高圧ガス管内の冷媒の溜まり込みを防止す
る。これによって、この装置にチャージする冷媒量の減
少を図ることができる。しかも、冷暖房同時運転時には凝縮機として作用する
室内熱交換器と、蒸発器として作用する室内熱交換器と
がシリーズ接続されるため熱回収による効率の良い運転
を行なうことができる。DETAILED DESCRIPTION OF THE INVENTION (A) Industrial application field The present invention is composed of one outdoor unit and a plurality of indoor units, and simultaneously cools or heats all of the plurality of rooms and simultaneously selects an arbitrary room. And a multi-room cooling and heating apparatus for cooling other rooms and heating other rooms. (B) Conventional technology A multi-room air-conditioning and heating apparatus capable of simultaneously cooling or heating all of a plurality of rooms and simultaneously cooling one of the plurality of rooms and heating the other room is disclosed in Japanese Patent Publication No. 52-24710 and Japanese Patent Publication No. 52-1982. No. 24711,
It is presented in Japanese Utility Model Publication No. 54-3020. (C) Problems to be Solved by the Invention The devices presented in the above-mentioned JP-B-52-24710 and JP-B-52-24711 require four-way switching valves and outdoor heat exchangers by the number of indoor units. Therefore, the piping circuit configuration is complicated and the manufacturing cost is high. Further, since two unit piping for each indoor unit must be drawn out of the outdoor unit, the number of unit piping is increased and piping work is troublesome. Had the disadvantage that Moreover, at the same time, during the cooling / heating operation for cooling one room and heating the other room, the outdoor heat exchangers corresponding to the respective indoor units act as condensers and evaporators, respectively, and dissipate heat to the outside. there were. Further, in the apparatus presented in the above-mentioned Japanese Utility Model Publication No. 54-3020, a combination of a room capable of cooling and a room capable of heating is determined during a cooling / heating operation in which a certain room of a plurality of rooms is simultaneously cooled and another room is heated. The cooling and heating operation could not be freely selected and performed in each room, so that there was a drawback that the usability was poor. The present invention solves the above-mentioned problems and provides a highly practical multi-room air conditioner. (D) Means for Solving the Problems The present invention comprises an outdoor unit having a compressor and an outdoor heat exchanger, and a plurality of indoor units having an indoor heat exchanger. The refrigerant discharge pipe and the refrigerant suction pipe of the compressor are branched and connected via a switching valve, and a unit-to-unit pipe connecting these indoor and outdoor units is connected to the refrigerant discharge pipe by a high-pressure gas pipe which is branched and connected to the refrigerant suction pipe. A low-pressure gas pipe branched and connected to a pipe, and a liquid pipe connected to the outdoor heat exchanger. Each of the indoor heat exchangers is connected to the high-pressure gas pipe and the low-pressure gas pipe via a switching valve. In a multi-chamber cooling and heating device connected to the liquid pipe via a refrigerant decompressor while being branched and connected, the high-pressure gas pipe and the high-pressure gas are connected by a bypass pipe for preventing accumulation of refrigerant in the high-pressure gas pipe. The refrigerant pressure is lower than that of the pipe. It is characterized by being connected to the piping between knits. (E) Function When cooling all the rooms at the same time, by setting the switching valve of the outdoor heat exchanger and the switching valve of each indoor heat exchanger to the cooling state, the refrigerant discharged from the compressor is discharged from the discharge pipe. After flowing to the outdoor heat exchanger and condensed and liquefied here, it is distributed to the refrigerant decompressor of each indoor unit via the liquid pipe, and then evaporated and vaporized in each indoor heat exchanger, and then the low-pressure gas pipe and refrigerant It is sucked into the compressor through the suction pipe in sequence. Thus, all the rooms are cooled by each indoor heat exchanger acting as an evaporator. When heating all the rooms at the same time, by setting the switching valve of the outdoor heat exchanger and the switching valve of each indoor heat exchanger to the heating state, the refrigerant discharged from the compressor is discharged to the discharge pipe and the high-pressure gas. The pipes are sequentially distributed to each indoor heat exchanger and then condensed and liquefied here.Then, the refrigerant pipes are joined through liquid refrigerant decompressors and then joined together by liquid pipes. Through the compressor. In this way, all the rooms are heated by each indoor heat exchanger acting as a condenser. When simultaneously cooling two rooms, for example, and heating one room, the switching valve of the outdoor heat exchanger is set to the heating state and the switching valve of the indoor heat exchanger of the indoor unit to be cooled is set to the cooling state. When the switching valve of the indoor heat exchanger of the indoor unit to be heated is set to the heating state, part of the refrigerant discharged from the compressor flows to the outdoor heat exchanger and the remaining refrigerant is heated via the high-pressure gas pipe. Flows into the indoor heat exchanger of the indoor unit to be condensed and liquefied by the indoor heat exchanger and the outdoor heat exchanger. The refrigerant condensed and liquefied by these heat exchangers is distributed to the refrigerant decompressors of each indoor unit via liquid tubes, and then evaporated and vaporized by each indoor heat exchanger, and then the low-pressure gas pipe is connected to the refrigerant suction pipe. Are sequentially sucked into the compressor. Thus, one room is heated by the indoor heat exchanger acting as a condenser, and two rooms are cooled by another indoor heat exchanger acting as an evaporator. Then, via the bypass pipe, the refrigerant in the high-pressure gas pipe is guided to the inter-unit pipe in which the refrigerant pressure is lower than that of the high-pressure gas pipe. (F) Embodiment The first embodiment of the present invention will be described with reference to FIG.
(1) is an outdoor unit having a compressor (2), an outdoor heat exchanger (3), and a gas-liquid separator (4), (5a), (5b), and (5c).
Is an indoor unit having indoor heat exchangers (6a), (6b) and (6c). The outdoor heat exchanger (3) is switched to a refrigerant discharge pipe (7) and a refrigerant suction pipe (8) of a compressor (2). A branch pipe (10) connecting the outdoor unit (1) and the indoor units (5a) (5b) (5c) is connected to the refrigerant discharge pipe (7) while branch-connected via the valves (9a) (9b). A high pressure gas pipe (11) branched and connected, a low pressure gas pipe (12) branched and connected to a refrigerant suction pipe (8), and a liquid pipe (1) connected to an outdoor heat exchanger (3).
3) and each indoor heat exchanger (6a) (6b) (6c)
Are connected to the high-pressure gas pipe (11) and the low-pressure gas pipe (12) via switching valves (14a) (15a), (14b) (15b), (14c) (15c), respectively. 13) are connected via refrigerant pressure reducers (16a) (16b) (16c) such as electric expansion valves. (17) is a bypass pipe connecting the high-pressure gas pipe (11) and the low-pressure gas pipe (12), and has a capillary throttle (18) for restricting the refrigerant flow. (19) is an evaporation pressure regulating valve interposed in the low-pressure gas pipe (12), and (20) is an auxiliary refrigerant decompressor such as an electric expansion valve interposed in the liquid pipe (13). Next, the driving operation will be described. When cooling all the rooms at the same time, one of the switching valves (9a) of the outdoor heat exchanger (3) is opened, the other switching valve (9b) is closed, and the indoor heat exchanger (6) is closed.
a) One of the switching valves (14a) (14b) (14c) of (6b) and (6c)
By closing the other switching valves (15a), (15b), and (15c), the refrigerant discharged from the compressor (2) discharges the discharge pipe (7), the switching valve (9a), and the outdoor heat exchanger (3). ) And condensed and liquefied here, and then through the liquid pipe (13), the refrigerant decompressors (16a) (16) (16) of each indoor unit (5a) (5b) (5c)
b) Distributed to (16c) where the pressure is reduced. Then, after evaporating and evaporating in each indoor heat exchanger (6a) (6b) (6c), switching valves (15a) (15b) (15c), low-pressure gas pipe (12),
It is sucked into the compressor (2) through the suction pipe (8) and the gas-liquid separator (4) in order. Thus, all the rooms are simultaneously cooled by the indoor heat exchangers (6a), (6b), and (6c) acting as evaporators. During the simultaneous cooling operation, the refrigerant discharged from the compressor (2) is guided from the high-pressure gas pipe (11) to the low-pressure gas pipe (12) through the bypass pipe (17). Will not accumulate. Conversely, when heating all the rooms simultaneously, one of the switching valves (9a) of the outdoor heat exchanger (3) is closed and the other switching valve (9b) is opened, and the indoor heat exchangers (6a) (6b) (6c)
By opening one of the switching valves (14a) (14b) (14c) and closing the other switching valve (15a) (15b) (15c), the refrigerant discharged from the compressor (2) is discharged from the discharge pipe (7). ),
Switching valves (14a) (14b) (14
c), distributed to indoor heat exchangers (6a) (6b) (6c)
Here, after each condensed and liquefied, each refrigerant decompressor (16a) (16
b) The pressure is reduced in (16c), and the liquid is combined in the liquid pipe (13). After that, the liquid is evaporated and vaporized in the outdoor heat exchanger (3).
b), it is sucked into the compressor (2) through the suction pipe (8) and the gas-liquid separator (4) sequentially. Thus, all the rooms are simultaneously heated by the indoor heat exchangers (6a) (6b) (6c) acting as condensers. In order to simultaneously cool two rooms and heat one room at the same time, for example, one switching valve (9a) of the outdoor heat exchanger (3) is opened and the other switching valve (9b) is closed, and cooling is performed. Switching valve (14a) (14c) of the indoor unit (5a) (5c)
Is closed and the other switching valve (15a) (15c) is opened and one switching valve (14b) of the indoor unit (5b) for heating is heated.
Is opened and the other switching valve (15b) is closed, a part of the refrigerant discharged from the compressor (2) passes through the discharge pipe (7) and the switching valve (9) a in order, and the outdoor heat exchanger (3) And the remaining refrigerant flows through the high-pressure gas pipe (11) to the switching valve (14b) and the indoor heat exchanger (6b) of the indoor unit (5b) for heating, and the indoor heat exchanger (6b) and the outdoor Heat exchanger (3)
And condensed and liquefied. And these heat exchangers (6b)
The refrigerant condensed and liquefied in (3) is decompressed by the refrigerant decompressors (16a) and (16c) of the indoor units (5a) and (5c) via the liquid pipe (13), and then the respective indoor heat exchangers (6a) Evaporated and vaporized in (6c), and then merged in the low-pressure gas pipe (12) through each switching valve (15a) (15c), and the suction pipe (8) and the gas-liquid separator (4)
Are sequentially sucked into the compressor (2). Thus, one room is heated by the indoor heat exchanger (6b) acting as a condenser, and the other indoor heat exchangers (6a) (6) acting as an evaporator are heated.
In c), the two rooms are cooled. During the simultaneous cooling and heating operation, the refrigerant pressure reducer (16b) of the indoor unit (5b) is fully opened to prevent refrigerant pressure loss, but the liquid refrigerant pressure in the liquid pipe (13) is not unbalanced. The pressure is adjusted by the auxiliary refrigerant pressure reducer (20). When the simultaneous cooling and heating operation is performed in winter, the indoor heat exchangers (6a) and (6c) of the indoor units (5a) and (5c) that are cooling because the low-pressure refrigerant pressure is affected by the outside air temperature
The internal pressure of the refrigerant easily falls to 4 kg / cm ² or less. For this reason, when a pressure drop (4 kg / cm ² or less) occurs, the pressure drop is prevented by restricting the evaporation pressure regulating valve (19). In other words, since the refrigerant pressure in the indoor heat exchangers (6a) and (6b) is maintained at a predetermined value or more by the throttle operation of the evaporation pressure adjusting valve (19), the indoor heat exchanger (6a)
(6b) will not freeze. The evaporating pressure control valve (1
9) is installed in the low-pressure gas pipe (12) instead of each switching valve (1
5a) (15b) (15c) and the low pressure gas pipe (12), that is, the pipes (21a) (21b) (21c) on the inflow side of the low pressure gas pipe (12)
May be provided respectively. Also, instead of providing the evaporation pressure adjusting valve (19), the refrigerant pressure in the indoor heat exchangers (6a) (6c) is reduced to 4k.
g / cm ² or less, the opening degree of the refrigerant decompressor (16a) (16c) is reduced, and when the freezing is released, the refrigerant decompressor (16a) (1
The opening degree of 6c) may be returned to the original. Further, at the time of the simultaneous cooling and heating operation, the rotation speed of the outdoor fan (22) for cooling the outdoor heat exchanger (3) is made lower than the rotation speed of the outdoor fan (22) in the simultaneous heating operation of all the rooms, so that the high pressure of the refrigerant is reduced. In order to prevent the pressure from decreasing, the heating capacity of the indoor unit (5b) does not decrease as compared with the heating capacity of the simultaneous heating operation in all the rooms. Thus, each indoor unit (5a) (5b) (5c) has its own switching valve (14a) (15a), (14b) (15b), (14c) (1
By opening and closing 5c), the cooling and heating operation can be arbitrarily performed. When one room is cooled and two rooms are heated, it is possible to operate the auxiliary refrigerant pressure reducer (20). For example, when cooling with the indoor unit (5b) and heating with the indoor unit (5a) (5c), one of the switching valves (9a) of the outdoor heat exchanger (3) is closed and the other switching valve (9b) is opened. One of the switching valves (14a) of the indoor units (5a) and (5c) for heating and closing one switching valve (14b) of the indoor unit (5b) for cooling and opening the other switching valve (15b) for heating. 14c) and open the other switching valve (15a) (15
When c) is closed, the refrigerant discharged from the compressor (2) passes through the discharge pipe (7) and the high-pressure gas pipe (11) in this order, and the switching valve (14a)
(14c) and each indoor heat exchanger (6a) (6c)
Is condensed and liquefied. Then, the liquefied refrigerant flows into the liquid pipe (13) via the refrigerant decompressors (16a) (16c) which are fully opened, respectively, and a part of the liquid refrigerant in the liquid pipe is converted into the refrigerant depressurizer (16b)
After the pressure is reduced in the indoor heat exchanger (6b), and the remaining liquid refrigerant is reduced in pressure in the auxiliary refrigerant pressure reducer (20), and then evaporated and vaporized in the outdoor heat exchanger (3). , And sequentially sucked into the compressor (2) through the gas-liquid separator (4). Indoor heat exchangers acting as condensers (6a) (6c)
, Two rooms are heated, and one room is cooled by another indoor heat exchanger (6b) acting as an evaporator. Even during the simultaneous cooling and heating operation, a part of the high-pressure gas refrigerant discharged from the compressor (2) is partially removed from the indoor unit (5c).
Although the high-pressure gas refrigerant flows toward the indoor unit (5b) side (to the right of the indoor unit (5c) in FIG. 1), the high-pressure gas refrigerant that has flowed in passes through the bypass pipe (17). Since the pressure is led to the unit-to-unit piping where the pressure drops, that is, to the low-pressure gas pipe (12), the high-pressure gas pipe (11)
The refrigerant does not accumulate in the air. As described above, since the high-pressure gas pipe (11) is not in a dead end state, it is not necessary to charge the apparatus with the refrigerant on the premise that the refrigerant is accumulated in the high-pressure gas pipe (11), and the amount of the refrigerant is reduced. be able to. As described above, when the number of rooms to be cooled (cooling capacity) is larger than the number of rooms to be heated (heating capacity), the outdoor heat exchanger (3)
When the number of the rooms to be heated (heating capacity) is smaller than the number of the rooms to be cooled (cooling capacity), the outdoor heat exchanger (3) acts as an evaporator. Heating and cooling can be performed freely, and heat recovery is performed in each of the indoor heat exchangers that function as an evaporator and a condenser during the simultaneous cooling and heating operation, so that operation efficiency can be improved. Also, during the above-mentioned cooling operation for all rooms, for example, the indoor unit (5
If only b) is switched to heating operation, the switching valve (14b) (15
b) is closed, and the refrigerant decompressor (16b) is almost opened. As a result, the refrigerant in the liquid pipe (13) flows into the indoor heat exchanger (16b) via the refrigerant pressure reducer (16b), so that the refrigerant in the indoor heat exchanger (16b), which has been in a low pressure state due to the cooling operation, Pressure rises. With this configuration, even when the switching valve (14b) is opened with the start of the heating operation, the generation of the refrigerant noise due to the refrigerant pressure difference is prevented. Similarly, during the heating operation in all rooms, for example, the indoor unit (5b)
When switching only to the cooling operation, the switching valve (14b) and the refrigerant pressure reducer (16b) are closed, and the switching valve (15b) is slightly opened. As a result, the refrigerant pressure of the indoor heat exchanger (16b) which has been in a high pressure state due to the heating operation is changed to the switching valve (1).
The refrigerant is guided to the low-pressure gas pipe (12) via 5b), and forcibly reduces the refrigerant pressure of the indoor heat exchanger (5b). Or
The switching valve (15b) is also closed to naturally reduce the refrigerant pressure in the indoor heat exchanger (16b). Opening the switching valve (15b) after reducing the refrigerant pressure in the indoor heat exchanger (16b) prevents generation of refrigerant noise due to the refrigerant pressure difference. Thus, the indoor unit is changed from the cooling operation to the heating operation,
Alternatively, when switching from the heating operation to the cooling operation, the refrigerant pressure of the indoor heat exchanger of this indoor unit is adjusted by the two switching valves and the refrigerant decompressor. Is prevented from being generated. In order to open the switching valve (15b) slightly, the switching valve (15b)
Since an expensive motorized valve whose opening can be adjusted is used as a valve, if a bypass capillary for pressure relief is provided in parallel with the switching valve (15b) and the other switching valves (15a) (15c), the switching valve As (15a), (15b) and (15c), simple on-off valves can be used. FIG. 2 shows a second embodiment of the present invention. When the indoor unit (5c) is installed in an annual cooling room such as a computer room, the switching unit (14c) (15c) is used directly. The indoor heat exchanger (6c) is connected to the low-pressure gas pipe (12). FIG. 3 shows a third embodiment of the present invention. When the indoor heat exchanger (6c) is used for annual heating and hot water supply, the indoor heat exchanger (6c) is directly used without using the switching valves (14c) (15c). The heat exchanger (6c) is connected to the high-pressure gas pipe (11). FIG. 4 shows a fourth embodiment of the present invention, in which the pipes in the indoor units (5a), (5b), (5c) are connected as shown to switch valves (14a) (15a), (14b). (15b), (14c) (1
5c), and a refrigerant decompressor (16a) (16b) (16c), and a check valve (23a) (23b) (23c). During cooling, the liquid refrigerant from the liquid pipe (13) is Refrigerant pressure reducer (16a) (1
6b) After the pressure is reduced in (16c), the indoor heat exchanger (6a) (6
b) (6c)-switching valve (15a) (15b) (15c)-low pressure gas pipe (12), and during heating, gas refrigerant from high pressure gas pipe (11) is switched to switching valve (14a) (14b) ( 14c)-Indoor heat exchanger (6
a) (6b) (6c) -check valve (23a) (23b) (23c) -liquid pipe (13) except that it flows in the same manner as the first embodiment. FIG. 5 shows a fifth embodiment of the present invention, in which each indoor heat exchanger (6a) (6b) (6c) is connected to a first heat exchanger (61a).
(61b) (61c) and the second heat exchanger (62a) (62b) (62c)
And a refrigerant decompressor (24a) (24b) (24c) for dehumidification such as an electric expansion valve is provided between the two heat exchangers, and from the liquid pipe (13) during cooling. Is depressurized by the refrigerant decompressors (16a), (16b), (16c), and then the first heat exchangers (61a), (61b), (61c) —the fully-opened dehumidifying refrigerant decompressors (24a), (24b) ) (24c)-second heat exchanger (62a) (62b)
(62c) -The first and second heat exchangers (61a) (62a), (61a) which flow through the switching valves (15a), (15b) and (15c) and act as evaporators.
b) Air is cooled in (62b), (61c) and (62c), respectively. on the other hand,
During heating, the gas refrigerant from the high pressure gas pipe (11)
a) (14b) (14c)-second heat exchanger (62a) (62b) (62
c)-Dehumidifying refrigerant decompressor (24a) (24b) (24
c)-the first heat exchanger (61a) (61b) (61c)-the refrigerant pressure reducer (16a) (16b) (16c)-the liquid pipe (13), and the first and second heats acting as condensers Exchanger (61a) (62a), (61
b) Air is cooled in (62b), (61c) and (62c), respectively. In addition, during dehumidification, the refrigerant decompressor (16a) (16b) (16c)-the first heat exchanger (61a) in which the liquid refrigerant from the liquid pipe (13) is fully open.
(61b) (61c) Dehumidifying refrigerant decompressor (24a) (24b)
After the pressure is reduced in (24c), the second heat exchanger (62a) (62b)
(62c) -The indoor air cooled by the second heat exchangers (62a), (62b) and (62c) which flow through the switching valves (15a) (15b) and (15c) and function as evaporators function as condensers (1) Reheated in the heat exchangers (61a), (61b), and (61c) to dehumidify. In each of the above embodiments, three indoor units (5a) (5
b) Although (5c) was used, even in the case of four or more indoor units having different capacities, it is only necessary to branch and connect to the unit-to-unit piping (10). If a variable capacity compressor such as a pole number conversion type or an unloader type is used, the operation of any indoor unit can be stopped. (G) Effect of the Invention In the present invention, since the piping between the units connecting the outdoor unit and the plurality of indoor units is constituted by three refrigerant pipes of the high-pressure gas pipe, the low-pressure gas pipe, and the liquid pipe, a single function is provided. Under the simple circuit configuration using the outdoor heat exchanger, the simultaneous cooling operation and simultaneous heating operation of a plurality of indoor units can be freely selected and performed in any indoor unit of simultaneous cooling and heating operation. . Then, through the bypass pipe, the refrigerant in the high-pressure gas pipe is guided to the inter-unit pipe where the refrigerant pressure is lower than that of the high-pressure gas pipe, thereby preventing accumulation of the refrigerant in the high-pressure gas pipe. As a result, it is possible to reduce the amount of refrigerant charged to the device. In addition, during simultaneous cooling and heating operation, the indoor heat exchanger acting as a condenser and the indoor heat exchanger acting as an evaporator are connected in series, so that efficient operation by heat recovery can be performed.

【図面の簡単な説明】第１図は本発明の第１実施例を示す多室型冷暖房装置の
冷媒回路図、第２図は本発明の第２実施例を示す多室型
冷暖房装置の冷媒回路図、第３図は本発明の第３実施例
を示す多室型冷暖房装置の冷媒回路図、第４図は本発明
の第４実施例を示す多室型冷暖房装置の冷媒回路図、第
５図は本発明の第５実施例を示す多室型冷暖房装置の冷
媒回路図である。（１）……室外ユニット、（２）……圧縮機、（３）…
…室外熱交換器、（5a）（5b）（5c）……室内ユニッ
ト、（6a）（6b）（6c）……室内熱交換器、（７）……
冷媒吐出管、（８）……冷媒吸込管、（9a）（9b）……
切換弁、（10）……ユニット間配管、（11）……高圧ガ
ス管、（12）……低圧ガス管、（13）……液管、（14
a）（14b）（14c），（15a）（15b）（15c）……切換
弁、（16a）（16b）（16c）……冷媒減圧器、（17）…
…バイパス管。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a refrigerant circuit diagram of a multi-room air-conditioning apparatus showing a first embodiment of the present invention, and FIG. 2 is a refrigerant of a multi-room air-conditioning apparatus showing a second embodiment of the present invention. FIG. 3 is a circuit diagram of a refrigerant circuit of a multi-room air conditioner showing a third embodiment of the present invention, FIG. 4 is a refrigerant circuit diagram of a multi room air conditioner showing a fourth embodiment of the present invention, FIG. FIG. 5 is a refrigerant circuit diagram of a multi-room air conditioner showing a fifth embodiment of the present invention. (1) ... outdoor unit, (2) ... compressor, (3) ...
... outdoor heat exchanger, (5a) (5b) (5c) ... indoor unit, (6a) (6b) (6c) ... indoor heat exchanger, (7) ...
Refrigerant discharge pipe, (8) ... refrigerant suction pipe, (9a) (9b) ...
Switching valve, (10) ... Unit-to-unit piping, (11) ... High-pressure gas pipe, (12) ... Low-pressure gas pipe, (13) ... Liquid pipe, (14)
a) (14b) (14c), (15a) (15b) (15c) ... switching valve, (16a) (16b) (16c) ... refrigerant decompressor, (17) ...
... bypass pipe.

Claims

(57) [Claims] An outdoor unit having a compressor and an outdoor heat exchanger,
A plurality of indoor units having an indoor heat exchanger, wherein the outdoor heat exchanger is branched and connected to a refrigerant discharge pipe and a refrigerant suction pipe of a compressor via a switching valve, and the indoor and outdoor units are connected to each other. The inter-unit piping is composed of a high-pressure gas pipe branched and connected to the refrigerant discharge pipe, a low-pressure gas pipe branched and connected to the refrigerant suction pipe, and a liquid pipe connected to the outdoor heat exchanger. In a multi-room cooling and heating device in which an indoor heat exchanger is branched and connected to the high-pressure gas pipe and the low-pressure gas pipe via a switching valve and connected to the liquid pipe via a refrigerant decompressor, A multi-room air conditioner, wherein the high-pressure gas pipe is connected to an inter-unit pipe having a lower refrigerant pressure than the high-pressure gas pipe by a bypass pipe for preventing accumulation of refrigerant.