JP3982893B2

JP3982893B2 - Air conditioner

Info

Publication number: JP3982893B2
Application number: JP02396798A
Authority: JP
Inventors: 直人坂本; 一廣志村; 岳志渡部
Original assignee: Sanyo Electric Co Ltd
Current assignee: Sanyo Electric Co Ltd
Priority date: 1998-01-21
Filing date: 1998-01-21
Publication date: 2007-09-26
Anticipated expiration: 2018-01-21
Also published as: JPH11211245A

Description

【０００１】
【発明の属する技術分野】
本発明は空気調和装置に関する。
【０００２】
【従来の技術】
図３に示すように、空気調和装置１は、室外ユニット２及び室内ユニット３を有してなり、室外ユニット２の室外冷媒配管４と室内ユニット３の室内冷媒配管５とが連結して構成される。室外冷媒配管４には、アキュムレータ６、圧縮機７、四方弁８、室外熱交換器９及び室外電動膨張弁１０が配設されている。また、室内冷媒配管５には、室内熱交換器１１及び室内電動膨張弁１２が配設されている。
【０００３】
四方弁８の切換操作により冷房運転と暖房運転とが切り換えられる。暖房運転時には、室外冷媒配管４及び室内冷媒配管５内を実線矢印の如く冷媒が流れて、室内熱交換器１１により室内が冷房される。暖房運転時には、室外冷媒配管４及び室内冷媒配管５内を破線矢印の如く冷媒が流れて、室内熱交換器１１により室内が暖房される。
【０００４】
ところで、空気調和装置１の暖房運転停止時には、夜間、低温状態となる室外熱交換器９内に冷媒が多量に貯溜しないように、室外電動膨張弁１０が全閉操作されるのが一般的である。
【０００５】
【発明が解決しようとする課題】
ところが、明け方、朝日によって室外熱交換器９の温度が上昇して、この室外熱交換器９内の液冷媒が気化したとき、上述のように室外電動膨張弁１０が全閉操作されていると、圧縮機７から四方弁８及び室外熱交換器９を経て室外電動膨張弁１０へ至る室外冷媒配管４内の圧力が上昇してしまう。このため、圧縮機７の吐出側における室外冷媒配管４内が高圧状態となり、空気調和装置１の暖房運転開始時に圧縮機７の負荷が増大してしまう。
【０００６】
本発明の課題は、上述の事情を考慮してなされたものであり、暖房運転開始時の圧縮機の負荷を低減させることができる空気調和装置を提供することにある。
【０００７】
【課題を解決するための手段】
請求項１記載の発明は、圧縮機、室外熱交換器及び減圧装置が室外冷媒配管により接続されて構成された室外ユニットと、上記室外冷媒配管に連結可能な室内冷媒配管に室内熱交換器が配設されて構成された室内ユニットとを有する空気調和装置において、上記室外冷媒配管には、少なくとも上記減圧装置を迂回するバイパス配管が接続され、このバイパス配管には逆止弁が設けられ、上記圧縮機の暖房運転停止時に上記減圧装置を全閉とし、この全閉状態で、上記圧縮機から上記室外熱交換器を経て上記減圧装置へ至る上記室外冷媒配管内の高圧冷媒の圧力が、上記減圧装置よりも暖房運転時における上流側の上記室外冷媒配管内の圧力を超えた場合に、上記逆止弁を経由して上記高圧冷媒を上記上流側の室外冷媒配管へ導くものであり、さらに、上記バイパス配管は、減圧装置及び室外熱交換器を迂回するものである。
【０００９】
請求項１に記載の発明によれば、次の作用がある。
【００１０】
室外冷媒配管には、少なくとも減圧装置を迂回するバイパス配管が接続され、このバイパス配管には逆止弁が設けられ、圧縮機の暖房運転停止時に減圧装置を全閉とし、圧縮機から室外熱交換器を経て全閉状態の減圧装置へ至る室外冷媒配管内の高圧冷媒の圧力が、全閉状態の減圧装置よりも暖房運転時における上流側の室外冷媒配管内の圧力を超えた場合に、上記逆止弁を経由して上記高圧冷媒を上記上流側の室外冷媒配管へ導くものであり、さらに、上記バイパス配管は、減圧装置及び室外熱交換器を迂回するので、夜間、暖房運転停止中に、室外熱交換器及びその周囲の室外冷媒配管内に貯溜された液冷媒が、朝日等により昇温されて気化し高圧冷媒となっても、この高圧冷媒が逆止弁を経て、減圧装置よりも暖房運転時における上流側の室外冷媒配管内へ導かれる。このため、暖房運転停止中に圧縮機の吐出側が高圧状態とならないので、暖房運転開始時に圧縮機の負荷を低減させることができる。
【００１３】
【発明の実施の形態】
以下、本発明の実施の形態を図面に基づいて説明する。
【００１４】
［Ａ］発明の前提となる実施態様
図１は、本発明に係る空気調和装置の前提となる実施態様を示す冷媒回路図である。
【００１５】
図１に示すように、空気調和装置２０は、室外ユニット２１及び室内ユニット２２を有してなり、室外ユニット２１の室外冷媒配管２３と、室内ユニット２２の室内冷媒配管２４とが連結して構成される。
【００１６】
室外ユニット２１は、室外に設置され、室外冷媒配管２３に圧縮機２５が配設され、この圧縮機２５の吸込側にアキュムレータ２６が、吐出側に四方弁２７が室外冷媒配管２３を介してそれぞれ接続され、この四方弁２７に、室外熱交換器２８と減圧装置としての室外電動膨張弁２９とが室外冷媒配管２３を介し順次接続されて構成される。室外熱交換器２８には、この室外熱交換器２８へ向かって送風する図示しないファンが隣接して配置されている。
【００１７】
また、上記室外電動膨張弁２９は、空気調和装置２０の暖房運転時に開度が調整されて冷媒を減圧し、空気調和装置２０の暖房運転停止時には全閉操作される。室外電動膨張弁２９を空気調和装置２０の暖房運転停止時に仮に全開状態とすると、夜間に室外熱交換器２８が冷却されて、この室外熱交換器２８内及び室外熱交換器２８まわりの室外冷媒配管２３内が低圧状態となり、室外冷媒配管２３及び室内冷媒配管２４内の液冷媒が、室外熱交換器２８を含む室外熱交換器２８周囲の室外冷媒配管２３内へ多量に貯溜してしまう。従って、空気調和装置２０の暖房運転停止時に、室外熱交換器２８を含む室外熱交換器２８周囲の室外冷媒配管２３に多量の液冷媒が貯溜するのを防止するために、上述の如く、暖房運転停止時に室外電動膨張弁２９が全閉操作される。
【００１８】
一方、室内ユニット２２は、室内に設置され、室内冷媒配管２４に室内熱交換器３０が配設され、室内冷媒配管２４において暖房運転時に液冷媒が流れる室内熱交換器３０近傍に室内電動膨張弁３１が配設されて構成される。この室内電動膨張弁３１は、空調負荷に応じて開度が調整される。また、室内熱交換器３０には、この室内熱交換器３０へ送風するファン(不図示)が隣接して配置されている。
【００１９】
上述の空気調和装置２０は、四方弁２７を切り換えることにより、室外冷媒配管２３及び室内冷媒配管２４内を流れる冷媒の流れが変更されて、冷房運転又は暖房運転が実施される。
【００２０】
空気調和装置２０が冷房側に切り換えられたときには、冷媒が室外冷媒配管２３及び室内冷媒配管２４内を図２の実線矢印の如く流れ、室外熱交換器２８が凝縮器に、室内熱交換器３０が蒸発器になって冷房運転状態となり、室内熱交換器３０が室内を冷房する。
【００２１】
また、四方弁２７が暖房側に切り換えられたときには、冷媒が室外冷媒配管２３及び室内冷媒配管２４内を図１の破線矢印の如く流れ、室内熱交換器３０が凝縮器に、室外熱交換器２８が蒸発器となって暖房運転状態となり、室内熱交換器３０が室内を暖房する。
【００２２】
さて、上述のような空気調和装置２０においては、室外ユニット２１の室外冷媒配管２３に室外電動膨張弁２９を迂回するバイパス配管３２が接続され、このバイパス配管３２に逆止弁３３が配設されている。つまり、バイパス配管３２は、一端が室外熱交換器２８と室外電動膨張弁２９との間の室外冷媒配管２３に接続され、他端が室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３に接続される。
【００２３】
また、逆止弁３３は、空気調和装置２０の運転停止時に、圧縮機２５から四方弁２７及び室外熱交換器２８を経て室外電動膨張弁２９(全閉状態)へ至る室外冷媒配管２３内の冷媒が、室外熱交換器２８に朝日があたることにより昇温されて高圧冷媒となったとき、この高圧冷媒を、全閉状態の室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３内へ導く方向に冷媒を流す。従って、また、この逆止弁３３は、空気調和装置２０の冷房運転時に、室外電動膨張弁２９の容量以上の冷媒が室外熱交換器２８から室外電動膨張弁２９へ流れるときに、その冷媒の一部をバイパス配管３２を経て、室外電動膨張弁２９よりも冷房運転時における下流側の室外冷媒配管２３内へ流すことも可能である。
【００２４】
以上のことから、この態様の空気調和装置２０によれば、次の効果を奏する。
【００２５】
▲１▼室外冷媒配管２３には、室外電動膨張弁２９を迂回するバイパス配管３２が接続され、このバイパス配管３２には、空気調和装置２０の運転停止時に圧縮機２５から室外熱交換器２８を経て全閉状態の室外電動膨張弁２９へ至る室外冷媒配管２３内の高圧冷媒を、全閉状態の室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３内へ導く逆止弁３３が配設されたので、夜間、暖房運転停止中に、室外熱交換器２８及びその周囲の室外冷媒配管２３内に貯溜された液冷媒が、朝日等により昇温されて気化し高圧冷媒となっても、この高圧冷媒が逆止弁３３を経て、室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３内へ導かれる。このため、暖房運転停止中に室外熱交換器２８が朝日等により昇温されても、圧縮機２５から四方弁２７及び室外熱交換器２８を経て室外電動膨張弁２９(全閉状態)へ至る室外冷媒配管２３内の圧力と、この全閉状態の室外電動膨張弁２９よりも暖房運転時上流側の室外冷媒配管２３内の圧力とがバランスして、圧縮機２５の吐出側の室外冷媒配管２３内が高圧状態とならないので、暖房運転開始時に圧縮機２５の負荷を低減させることができる。
【００２６】
▲２▼逆止弁３３が配設されたバイパス配管３２が室外電動膨張弁２９のみを迂回することから、上述の効果▲１▼の如く、暖房運転開始時の圧縮機２５の負荷を低減させることができるとともに、冷房運転時に、開操作状態の室外電動膨張弁２９の容量を越える冷媒を、室外電動膨張弁２９の冷房運転時における下流側へ排出させることができるので、室外電動膨張弁２９の安全性を確保できる。
【００２７】
［Ｂ］本発明の実施の形態
図２は、本発明に係る空気調和装置の実施の形態を示す冷媒回路図である。この実施の形態において、上述した前提となる実施態様と同様な部分は、同一の符号を付すことにより説明を省略する。
【００２８】
図２に示す空気調和装置４０においては、逆止弁４２が配設されたバイパス配管４１が、室外熱交換器２８及び室外電動膨張弁２９を迂回して室外冷媒配管２３に接続されている。つまり、バイパス配管４１は、一端が、圧縮機２５と室外熱交換器２８との間の室外冷媒配管２３に接続され、他端が、室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３に接続される。また、逆止弁４２も、逆止弁３３と同様に、空気調和装置４０の暖房運転停止時に、室外熱交換器２８内及びその周囲の室外冷媒配管２３内に貯溜された液冷媒が、室外熱交換器２８に朝日があたるなどにより昇温されて高圧冷媒となったとき、この高圧冷媒を、室外電動膨張弁２９(全閉状態)よりも暖房運転時における上流側の室外冷媒配管２３内へ導く方向に冷媒を流す。
【００２９】
従って、この空気調和装置４０においては、次の効果を奏する。
【００３０】
▲３▼室外冷媒配管２３には、室外電動膨張弁２９及び室外熱交換器２８を迂回するバイパス配管４１が接続され、このバイパス配管４１には、空気調和装置４０の暖房運転停止時に、圧縮機２５から室外熱交換器２８を経て全閉状態の室外電動膨張弁２９へ至る室外冷媒配管２３内の高圧冷媒を、全閉状態の室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３内へ導く逆止弁４２が配設されたので、夜間、暖房運転停止中に、室外熱交換器２８及びその周囲の室外冷媒配管２３内に貯溜された液冷媒が、朝日等により昇温されて気化し高圧冷媒となっても、この高圧冷媒が逆止弁４２を経て、室外電動膨張弁２９よりも暖房運転時における上流側の室外冷媒配管２３内へ導かれる。このため、暖房運転停止中に、室外熱交換器２８が朝日等により昇温されても、圧縮機２５から四方弁２７及び室外熱交換器２８を経て室外電動膨張弁２９(全閉状態)へ至る室外冷媒配管２３内の圧力と、全閉状態の室外電動膨張弁２９よりも暖房運転時上流側の室外冷媒配管２３内の圧力とがバランスして、圧縮機２５の吐出側の室外冷媒配管２３内が高圧状態とならないので、暖房運転開始時に圧縮機２５の負荷を低減させることができる。
【００３１】
以上、一実施の形態に基づいて本発明を説明したが、本発明はこれに限定されるものではない。例えば、圧縮機、室外熱交換器、減圧装置及び室内熱交換器が順次接続された空気調和装置に本発明を適用してもよい。
【００３２】
【発明の効果】
以上のように、本発明に係る空気調和装置によれば、室外冷媒配管に、少なくとも減圧装置を迂回するバイパス配管が接続され、このバイパス配管には逆止弁が設けられ、圧縮機の暖房運転停止時に減圧装置を全閉とし、圧縮機から室外熱交換器を経て全閉状態の減圧装置へ至る室外冷媒配管内の高圧冷媒の圧力が、全閉状態の減圧装置よりも暖房運転時における上流側の室外冷媒配管内の圧力を超えた場合に、上記逆止弁を経由して上記高圧冷媒を上記上流側の室外冷媒配管へ導くものであり、さらに、上記バイパス配管は、減圧装置及び室外熱交換器を迂回することから、空気調和装置の暖房運転停止時に、室外熱交換器が昇温されても、バイパス配管及び逆止弁の作用により、圧縮機から室外熱交換器を経て減圧装置へ至る室外冷媒配管内の圧力と、減圧装置よりも暖房運転時における上流側の室外冷媒配管内の圧力とがバランスして、暖房運転開始時の圧縮機の負荷を低減させることができる。
【図面の簡単な説明】
【図１】本発明に係る空気調和装置の前提となる実施態様を示す冷媒回路図である。
【図２】本発明に係る空気調和装置の実施の形態を示す冷媒回路図である。
【図３】従来の空気調和装置を示す冷媒回路図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air conditioner.
[0002]
[Prior art]
As shown in FIG. 3, the air conditioner 1 includes an outdoor unit 2 and an indoor unit 3, and is configured by connecting an outdoor refrigerant pipe 4 of the outdoor unit 2 and an indoor refrigerant pipe 5 of the indoor unit 3. The An accumulator 6, a compressor 7, a four-way valve 8, an outdoor heat exchanger 9, and an outdoor electric expansion valve 10 are disposed in the outdoor refrigerant pipe 4. The indoor refrigerant pipe 5 is provided with an indoor heat exchanger 11 and an indoor electric expansion valve 12.
[0003]
Switching operation of the four-way valve 8 switches between cooling operation and heating operation. During the heating operation, the refrigerant flows in the outdoor refrigerant pipe 4 and the indoor refrigerant pipe 5 as indicated by solid arrows, and the indoor heat exchanger 11 cools the room. During the heating operation, the refrigerant flows in the outdoor refrigerant pipe 4 and the indoor refrigerant pipe 5 as indicated by broken arrows, and the indoor heat exchanger 11 heats the room.
[0004]
By the way, when the heating operation of the air conditioner 1 is stopped, the outdoor electric expansion valve 10 is generally fully closed so that a large amount of refrigerant is not stored in the outdoor heat exchanger 9 that is in a low temperature state at night. is there.
[0005]
[Problems to be solved by the invention]
However, when the temperature of the outdoor heat exchanger 9 rises by dawn and morning sun and the liquid refrigerant in the outdoor heat exchanger 9 is vaporized, the outdoor electric expansion valve 10 is fully closed as described above. Then, the pressure in the outdoor refrigerant pipe 4 from the compressor 7 through the four-way valve 8 and the outdoor heat exchanger 9 to the outdoor electric expansion valve 10 increases. For this reason, the inside of the outdoor refrigerant pipe 4 on the discharge side of the compressor 7 is in a high pressure state, and the load on the compressor 7 increases when the heating operation of the air conditioner 1 is started.
[0006]
The subject of this invention is made in view of the above-mentioned situation, and is providing the air conditioning apparatus which can reduce the load of the compressor at the time of heating operation start.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, an indoor heat exchanger is provided in an outdoor unit configured by connecting a compressor, an outdoor heat exchanger, and a decompression device by an outdoor refrigerant pipe, and in an indoor refrigerant pipe connectable to the outdoor refrigerant pipe. In the air conditioner having an indoor unit arranged and configured, the outdoor refrigerant pipe is connected to at least a bypass pipe that bypasses the decompression device, and the bypass pipe is provided with a check valve, When the heating operation of the compressor is stopped, the decompression device is fully closed, and in this fully closed state, the pressure of the high-pressure refrigerant in the outdoor refrigerant pipe from the compressor to the decompression device through the outdoor heat exchanger is if it exceeds the pressure on the upstream side of the outdoor refrigerant in the pipe during the heating operation than decompressor, which via the check valve directs the high pressure refrigerant to the outdoor refrigerant pipe of the upstream side, Luo, the bypass pipe is to bypass the pressure reducing device and an outdoor heat exchanger.
[0009]
According to invention of Claim 1, there exists the following effect | action.
[0010]
A bypass pipe that bypasses at least the decompression device is connected to the outdoor refrigerant piping, and a check valve is provided in the bypass piping. When the heating operation of the compressor is stopped, the decompression device is fully closed to exchange the outdoor heat from the compressor. When the pressure of the high-pressure refrigerant in the outdoor refrigerant pipe that reaches the fully-closed decompression device through the condenser exceeds the pressure in the upstream-side outdoor refrigerant pipe during heating operation than the fully-closed decompression device, The high-pressure refrigerant is led to the upstream outdoor refrigerant pipe via a check valve , and further, the bypass pipe bypasses the decompression device and the outdoor heat exchanger. Even if the liquid refrigerant stored in the outdoor heat exchanger and the outdoor refrigerant pipe around it is heated by Asahi etc. and vaporized to become a high-pressure refrigerant, the high-pressure refrigerant passes through the check valve and passes through the check valve. Also upstream during heating operation It is guided to the outdoor refrigerant in the pipe. For this reason, since the discharge side of the compressor does not become a high pressure state while the heating operation is stopped, the load on the compressor can be reduced when the heating operation is started.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
[A] embodiments Figure 1 as a premise of the invention is a refrigerant circuit diagram showing an embodiment which is a premise of an air conditioner according to the present invention.
[0015]
As shown in FIG. 1, the air conditioner 20 includes an outdoor unit 21 and an indoor unit 22, and is configured by connecting an outdoor refrigerant pipe 23 of the outdoor unit 21 and an indoor refrigerant pipe 24 of the indoor unit 22. Is done.
[0016]
The outdoor unit 21 is installed outdoors, and a compressor 25 is disposed in the outdoor refrigerant pipe 23. An accumulator 26 is provided on the suction side of the compressor 25, and a four-way valve 27 is provided on the discharge side via the outdoor refrigerant pipe 23. The outdoor heat exchanger 28 and an outdoor electric expansion valve 29 as a pressure reducing device are sequentially connected to the four-way valve 27 via an outdoor refrigerant pipe 23. A fan (not shown) that blows air toward the outdoor heat exchanger 28 is disposed adjacent to the outdoor heat exchanger 28.
[0017]
The outdoor electric expansion valve 29 is adjusted in opening during the heating operation of the air conditioner 20 to decompress the refrigerant, and is fully closed when the heating operation of the air conditioner 20 is stopped. If the outdoor electric expansion valve 29 is fully opened when the heating operation of the air conditioner 20 is stopped, the outdoor heat exchanger 28 is cooled at night, and the outdoor refrigerant around the outdoor heat exchanger 28 and the outdoor heat exchanger 28 is cooled. The inside of the pipe 23 is in a low pressure state, and a large amount of liquid refrigerant in the outdoor refrigerant pipe 23 and the indoor refrigerant pipe 24 is stored in the outdoor refrigerant pipe 23 around the outdoor heat exchanger 28 including the outdoor heat exchanger 28. Therefore, in order to prevent a large amount of liquid refrigerant from accumulating in the outdoor refrigerant pipe 23 around the outdoor heat exchanger 28 including the outdoor heat exchanger 28 when the heating operation of the air conditioner 20 is stopped, as described above, heating is performed. When the operation is stopped, the outdoor electric expansion valve 29 is fully closed.
[0018]
On the other hand, the indoor unit 22 is installed indoors, an indoor heat exchanger 30 is disposed in the indoor refrigerant pipe 24, and an indoor electric expansion valve is provided in the vicinity of the indoor heat exchanger 30 in which liquid refrigerant flows in the indoor refrigerant pipe 24 during heating operation. 31 is arranged. The opening degree of the indoor electric expansion valve 31 is adjusted according to the air conditioning load. Further, a fan (not shown) for sending air to the indoor heat exchanger 30 is disposed adjacent to the indoor heat exchanger 30.
[0019]
In the air conditioner 20 described above, by switching the four-way valve 27, the flow of the refrigerant flowing in the outdoor refrigerant pipe 23 and the indoor refrigerant pipe 24 is changed, and the cooling operation or the heating operation is performed.
[0020]
When the air conditioner 20 is switched to the cooling side, the refrigerant flows through the outdoor refrigerant pipe 23 and the indoor refrigerant pipe 24 as indicated by solid arrows in FIG. 2, the outdoor heat exchanger 28 becomes a condenser, and the indoor heat exchanger 30 Becomes an evaporator and enters a cooling operation state, and the indoor heat exchanger 30 cools the room.
[0021]
Further, when the four-way valve 27 is switched to the heating side, the refrigerant flows in the outdoor refrigerant pipe 23 and the indoor refrigerant pipe 24 as indicated by the broken line arrows in FIG. 1, and the indoor heat exchanger 30 becomes the condenser, and the outdoor heat exchanger. 28 becomes an evaporator and becomes a heating operation state, and the indoor heat exchanger 30 heats the room.
[0022]
In the air conditioner 20 as described above, a bypass pipe 32 that bypasses the outdoor electric expansion valve 29 is connected to the outdoor refrigerant pipe 23 of the outdoor unit 21, and a check valve 33 is disposed in the bypass pipe 32. ing. That is, the bypass pipe 32 has one end connected to the outdoor refrigerant pipe 23 between the outdoor heat exchanger 28 and the outdoor electric expansion valve 29, and the other end connected to the outdoor side upstream of the outdoor electric expansion valve 29 during the heating operation. Connected to the refrigerant pipe 23.
[0023]
The check valve 33 is provided in the outdoor refrigerant pipe 23 from the compressor 25 to the outdoor electric expansion valve 29 (fully closed state) through the four-way valve 27 and the outdoor heat exchanger 28 when the operation of the air conditioner 20 is stopped. When the refrigerant is heated to a high-pressure refrigerant when the outdoor heat exchanger 28 is exposed to the sun, this high-pressure refrigerant is used as an outdoor refrigerant upstream of the fully-closed outdoor electric expansion valve 29 during heating operation. The refrigerant is caused to flow in a direction to be led into the pipe 23. Therefore, when the air conditioner 20 is in the cooling operation, the check valve 33 is used when refrigerant having a capacity larger than the capacity of the outdoor electric expansion valve 29 flows from the outdoor heat exchanger 28 to the outdoor electric expansion valve 29. A part of the refrigerant can flow through the bypass piping 32 and into the outdoor refrigerant piping 23 on the downstream side of the outdoor electric expansion valve 29 during the cooling operation.
[0024]
From the above, according to the air conditioner 20 of this embodiment, so the following effects.
[0025]
(1) A bypass pipe 32 that bypasses the outdoor electric expansion valve 29 is connected to the outdoor refrigerant pipe 23, and the outdoor heat exchanger 28 is connected to the bypass pipe 32 from the compressor 25 when the operation of the air conditioner 20 is stopped. A check valve that guides the high-pressure refrigerant in the outdoor refrigerant pipe 23 that reaches the fully-closed outdoor electric expansion valve 29 to the upstream-side outdoor refrigerant pipe 23 during heating operation from the fully-closed outdoor electric expansion valve 29. 33, the liquid refrigerant stored in the outdoor heat exchanger 28 and the outdoor refrigerant pipe 23 around the outdoor heat exchanger 28 and its surroundings during the heating operation stop at night is vaporized by being heated by Asahi or the like. Even so, the high-pressure refrigerant passes through the check valve 33 and is introduced into the outdoor refrigerant pipe 23 on the upstream side of the outdoor electric expansion valve 29 during the heating operation. For this reason, even if the outdoor heat exchanger 28 is heated by the sun or the like while the heating operation is stopped, the compressor 25 reaches the outdoor electric expansion valve 29 (fully closed state) via the four-way valve 27 and the outdoor heat exchanger 28. The pressure in the outdoor refrigerant pipe 23 and the pressure in the outdoor refrigerant pipe 23 on the upstream side of the fully-closed outdoor electric expansion valve 29 in the heating operation are balanced, and the outdoor refrigerant pipe on the discharge side of the compressor 25 is balanced. Since the inside of 23 does not become a high voltage | pressure state, the load of the compressor 25 can be reduced at the time of heating operation start.
[0026]
(2) Since the bypass pipe 32 provided with the check valve 33 bypasses only the outdoor electric expansion valve 29, the load on the compressor 25 at the start of the heating operation is reduced as described in the above effect (1). In addition, during the cooling operation, the refrigerant exceeding the capacity of the outdoor electric expansion valve 29 in the open operation state can be discharged to the downstream side during the cooling operation of the outdoor electric expansion valve 29. Therefore, the outdoor electric expansion valve 29 Can be secured.
[0027]
[B] Embodiment Figure 2 embodiment of the present invention is a refrigerant circuit diagram illustrating a form of implementation of an air conditioner according to the present invention. In the implementation form of this section, the same as embodiment as a premise described above will be omitted by retaining the same reference numerals.
[0028]
In the air conditioner 40 shown in FIG. 2, a bypass pipe 41 provided with a check valve 42 bypasses the outdoor heat exchanger 28 and the outdoor electric expansion valve 29 and is connected to the outdoor refrigerant pipe 23. That is, one end of the bypass pipe 41 is connected to the outdoor refrigerant pipe 23 between the compressor 25 and the outdoor heat exchanger 28, and the other end of the bypass pipe 41 is located upstream of the outdoor electric expansion valve 29 in the heating operation. Connected to the refrigerant pipe 23. Similarly to the check valve 33, the check valve 42 also has the liquid refrigerant stored in the outdoor heat exchanger 28 and the outdoor refrigerant pipe 23 around it when the heating operation of the air conditioner 40 is stopped. When the temperature of the heat exchanger 28 is increased by, for example, exposure to the sun, the high-pressure refrigerant is converted into the high-pressure refrigerant in the outdoor refrigerant pipe 23 on the upstream side during the heating operation from the outdoor electric expansion valve 29 (fully closed state). Let the coolant flow in the direction that leads to.
[0029]
Accordingly, in this air conditioner 40, so the following effects.
[0030]
(3) A bypass pipe 41 that bypasses the outdoor electric expansion valve 29 and the outdoor heat exchanger 28 is connected to the outdoor refrigerant pipe 23. When the heating operation of the air conditioner 40 is stopped, the bypass pipe 41 is connected to the compressor. The high-pressure refrigerant in the outdoor refrigerant pipe 23 extending from 25 through the outdoor heat exchanger 28 to the fully closed outdoor electric expansion valve 29 is more upstream than the fully closed outdoor electric expansion valve 29 in the heating operation. Since the check valve 42 that leads into the pipe 23 is disposed, the liquid refrigerant stored in the outdoor heat exchanger 28 and the surrounding outdoor refrigerant pipe 23 rises due to the morning sun or the like during the heating operation stop at night. Even when heated and vaporized, the high-pressure refrigerant passes through the check valve 42 and is introduced into the outdoor refrigerant pipe 23 upstream of the outdoor electric expansion valve 29 during the heating operation. For this reason, even if the outdoor heat exchanger 28 is heated by the morning sun or the like while the heating operation is stopped, the compressor 25 passes through the four-way valve 27 and the outdoor heat exchanger 28 to the outdoor electric expansion valve 29 (fully closed state). The pressure in the outdoor refrigerant pipe 23 reaching the outlet and the pressure in the outdoor refrigerant pipe 23 on the upstream side in the heating operation with respect to the fully-closed outdoor electric expansion valve 29 are balanced, and the outdoor refrigerant pipe on the discharge side of the compressor 25 is balanced. Since the inside of 23 does not become a high voltage | pressure state, the load of the compressor 25 can be reduced at the time of heating operation start.
[0031]
As mentioned above, although this invention was demonstrated based on one Embodiment, this invention is not limited to this. For example, the present invention may be applied to an air conditioner in which a compressor, an outdoor heat exchanger, a pressure reducing device, and an indoor heat exchanger are sequentially connected.
[0032]
【The invention's effect】
As described above, according to the air conditioner of the present invention, at least a bypass pipe that bypasses the decompression device is connected to the outdoor refrigerant pipe, and the bypass pipe is provided with a check valve, so that the heating operation of the compressor is performed. The pressure reducing device is fully closed when stopped, and the pressure of the high-pressure refrigerant in the outdoor refrigerant pipe from the compressor to the fully closed pressure reducing device through the outdoor heat exchanger is higher in the heating operation than the fully closed pressure reducing device. When the pressure in the outdoor refrigerant pipe on the side exceeds the pressure, the high-pressure refrigerant is led to the upstream outdoor refrigerant pipe via the check valve , and the bypass pipe further includes a decompression device and an outdoor By bypassing the heat exchanger, even when the outdoor heat exchanger is heated when the heating operation of the air conditioner is stopped, the pressure reducing device passes through the outdoor heat exchanger from the compressor by the action of the bypass pipe and the check valve. Outdoor refrigerant distribution to The pressure of the inner, and balance the pressure on the upstream side of the outdoor refrigerant in the pipe during the heating operation than decompressor, it is possible to reduce the load of the heating operation at the start of the compressor.
[Brief description of the drawings]
FIG. 1 is a refrigerant circuit diagram showing an embodiment as a premise of an air conditioner according to the present invention.
It is a refrigerant circuit diagram illustrating a form of implementation of the air conditioner according to the present invention; FIG.
FIG. 3 is a refrigerant circuit diagram showing a conventional air conditioner.

Claims

An indoor unit in which an indoor heat exchanger is disposed in an outdoor unit configured by connecting a compressor, an outdoor heat exchanger, and a decompression device through an outdoor refrigerant pipe, and an indoor refrigerant pipe connectable to the outdoor refrigerant pipe. In an air conditioner having a unit,
A bypass pipe that bypasses at least the pressure reducing device is connected to the outdoor refrigerant pipe, and a check valve is provided in the bypass pipe.
When the heating operation of the compressor is stopped, the decompression device is fully closed, and in this fully closed state, the pressure of the high-pressure refrigerant in the outdoor refrigerant pipe from the compressor to the decompression device via the outdoor heat exchanger is When the pressure in the outdoor refrigerant pipe on the upstream side during heating operation is higher than that in the decompression device, the high-pressure refrigerant is guided to the upstream outdoor refrigerant pipe via the check valve , Furthermore, the bypass pipe bypasses the decompression device and the outdoor heat exchanger .