JP2016090163A

JP2016090163A - Refrigeration device

Info

Publication number: JP2016090163A
Application number: JP2014226156A
Authority: JP
Inventors: 伸二長岡; Shinji Nagaoka
Original assignee: Daikin Industries Ltd
Current assignee: Daikin Industries Ltd
Priority date: 2014-11-06
Filing date: 2014-11-06
Publication date: 2016-05-23
Anticipated expiration: 2034-11-06
Also published as: JP6413662B2

Abstract

PROBLEM TO BE SOLVED: To provide a refrigeration device capable of preventing generation of "nonsteady refrigerant passing noise" at a curved portion even when the curved portion is disposed on a part of a pipe connected to an evaporator in an indoor unit to prevent interference with a peripheral component.SOLUTION: In an air conditioner 100, a pipe 50 connecting an electric expansion valve 14 and an indoor heat exchanger 15 is branched from one pipe into two branch pipes 541, 542 in an indoor unit (2). Branch pipe first curved portions 54d are respectively disposed on two branch pipes 541, 542. As a result, the total sum of flow channel cross-sectional areas becomes larger than a flow channel cross-sectional area before the branch pipes 541, 542, and "nonsteady refrigerant passing noise" generated at the branch pipe first curved portions 54d due to lowering of a refrigerant flow rate, can be prevented. Further as diameters of the branch pipes 541, 542 are smaller than a diameter of the pipe, a bending work can be easily implemented.SELECTED DRAWING: Figure 5

Description

本発明は、冷凍装置に関する。 The present invention relates to a refrigeration apparatus.

従来、特許文献１（特開２００８−２５６２７６号公報）に開示されているような室内ユニットでは、蒸発器に接続される配管の一部に周辺部品との干渉を避けるための湾曲部が設けられている（図４Ａ参照）。 Conventionally, in an indoor unit as disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2008-256276), a curved portion for avoiding interference with peripheral parts is provided in a part of piping connected to an evaporator. (See FIG. 4A).

ところが、室外ユニットからの冷媒が膨張弁を経て室内ユニットの熱交換器に入る段階で膨張弁と熱交換器とを結ぶ配管に湾曲部があると、その湾曲部において「非定常な冷媒通過音」が発生することがある。 However, if there is a curved part in the pipe connecting the expansion valve and the heat exchanger when the refrigerant from the outdoor unit passes through the expansion valve and enters the heat exchanger of the indoor unit, the "unsteady refrigerant passing sound" May occur.

膨張弁を経た冷媒は液相から液冷媒とガス冷媒とが混ざる二相状態となるが、その液相から二相状態に変わるポイントが非定常的に遷移することがあり、そのポイントが偶然に配管の湾曲部に遷移したときに「非定常な冷媒通過音」が発生すると推測されている。 The refrigerant that has passed through the expansion valve becomes a two-phase state in which the liquid refrigerant and the gas refrigerant are mixed from the liquid phase, but the point at which the liquid phase changes to the two-phase state may transit unsteadily, and that point happens by chance. It is presumed that “unsteady refrigerant passing sound” is generated when a transition is made to the curved portion of the pipe.

本発明の課題は、室内ユニット内の蒸発器に接続される配管の一部に周辺部品との干渉を避けるための湾曲部が設けられている場合であっても、その湾曲部での「非定常な冷媒通過音」の発生が防止される冷凍装置を提供することにある。 The problem of the present invention is that even when a curved portion for avoiding interference with peripheral parts is provided in a part of the pipe connected to the evaporator in the indoor unit, An object of the present invention is to provide a refrigeration apparatus that prevents the occurrence of a “steady refrigerant passage noise”.

本発明の第１観点に係る冷凍装置は、圧縮機、凝縮機、膨張機構及び蒸発器が順に結ばれた冷媒回路のうちの少なくとも蒸発器を室内ユニットに配置し、蒸発器によって冷却を行う冷凍装置であって、膨張機構と蒸発器とを結ぶ配管が、室内ユニット内に配される湾曲部を有している。湾曲部の流路面積は、その配管のうち湾曲部より膨張機構側に在る部分の流路断面積よりも大きい。 A refrigeration apparatus according to a first aspect of the present invention is a refrigeration system in which at least an evaporator in a refrigerant circuit in which a compressor, a condenser, an expansion mechanism, and an evaporator are connected in order is arranged in an indoor unit and cooled by the evaporator. In the apparatus, a pipe connecting the expansion mechanism and the evaporator has a curved portion arranged in the indoor unit. The flow path area of the curved portion is larger than the cross-sectional area of the portion of the pipe that is closer to the expansion mechanism than the curved portion.

この冷凍装置では、湾曲部で発生する「非定常な冷媒通過音」は冷媒の流速が速いほど発生し易い傾向にあることが出願人によって確認されており、この傾向に鑑みれば、その発生する箇所の流路断面積を拡大して冷媒流速を遅くすることによって、湾曲部で発生する「非定常な冷媒通過音」を防止することができる。 In this refrigeration apparatus, it has been confirmed by the applicant that the “unsteady refrigerant passing sound” generated at the curved portion tends to be generated as the flow velocity of the refrigerant increases. By enlarging the flow path cross-sectional area at a location and slowing down the refrigerant flow velocity, “unsteady refrigerant passage noise” generated at the curved portion can be prevented.

本発明の第２観点に係る冷凍装置は、第１観点に係る冷凍装置であって、膨張機構と蒸発器とを結ぶ配管が、室内ユニット内で１本の管から２本の分岐管に分岐されている。湾曲部は、２本の分岐管それぞれに設けられている。 A refrigeration apparatus according to a second aspect of the present invention is the refrigeration apparatus according to the first aspect, wherein a pipe connecting the expansion mechanism and the evaporator branches from one pipe to two branch pipes in the indoor unit. Has been. The bending portion is provided in each of the two branch pipes.

湾曲部の流路断面積を拡大するために管径の大きい管を採用すると、曲げ加工が困難な場合があり、仮に曲げ径を大きくすると湾曲部が周辺機器と干渉するという事態を招く虞がある。しかし、この冷凍装置では、１本の管が２本の分岐管に分岐することによって、流路断面積の総和は分岐管手前の流路断面積よりも大きくなり、分岐管の径は手前の管径よりも小さくすることができるので曲げ加工が容易になる。 If a pipe with a large pipe diameter is used to increase the flow path cross-sectional area of the curved portion, bending may be difficult, and if the bent diameter is increased, the curved portion may interfere with peripheral devices. is there. However, in this refrigeration system, one pipe branches into two branch pipes, so that the total cross-sectional area of the flow path becomes larger than the cross-sectional area of the flow path before the branch pipe, and the diameter of the branch pipe is Since it can be made smaller than the tube diameter, bending is facilitated.

本発明の第３観点に係る冷凍装置は、第２観点に係る冷凍装置であって、２本の分岐管を流れる冷媒が蒸発器に入る前に合流するように、２本の分岐管が一本の管に接続されている。 The refrigeration apparatus according to the third aspect of the present invention is the refrigeration apparatus according to the second aspect, wherein the two branch pipes are integrated so that the refrigerant flowing through the two branch pipes merges before entering the evaporator. Connected to the book tube.

この冷凍装置では、２本の分岐管を流れる冷媒を合流させずにそのまま蒸発器に入れてもよいが、再熱ドライなどを行う場合には冷媒は合流させて蒸発器に入れた方がよい。したがって、再熱ドライなどを行うタイプに有用である。 In this refrigeration apparatus, the refrigerants flowing through the two branch pipes may be put into the evaporator as they are without being merged. However, when performing reheat drying or the like, it is better to merge the refrigerants and put them into the evaporator. . Therefore, it is useful for types that perform reheat drying and the like.

本発明の第４観点に係る冷凍装置は、第１観点から第３観点のいずれか１つに係る冷凍装置であって、冷媒回路内を流通する冷媒が単一冷媒である。 A refrigeration apparatus according to a fourth aspect of the present invention is the refrigeration apparatus according to any one of the first to third aspects, wherein the refrigerant circulating in the refrigerant circuit is a single refrigerant.

単一冷媒では沸点が一箇所しかなく冷媒状態が液相から二相へ一気に変わるので、湾曲部における「非定常な冷媒通過音」の発生が顕著になると推測される。しかし、この冷凍装置では、湾曲部の流路面積が湾曲部より膨張機構側に在る部分の流路断面積よりも大きいので、単一冷媒を使用しても湾曲部における「非定常な冷媒通過音」の発生が防止される。 A single refrigerant has only one boiling point and the refrigerant state changes from a liquid phase to a two-phase at a stretch. Therefore, it is presumed that the occurrence of “unsteady refrigerant passing sound” in the curved portion becomes remarkable. However, in this refrigeration apparatus, since the flow passage area of the bending portion is larger than the flow passage cross-sectional area of the portion located on the expansion mechanism side from the bending portion, even if a single refrigerant is used, the “unsteady refrigerant in the bending portion” Generation of “passing sound” is prevented.

本発明の第５観点に係る冷凍装置は、第１観点から第３観点のいずれか１つに係る冷凍装置であって、冷媒回路内を流通する冷媒がＲ３２の単一冷媒である。 A refrigeration apparatus according to a fifth aspect of the present invention is the refrigeration apparatus according to any one of the first to third aspects, wherein the refrigerant circulating in the refrigerant circuit is a single refrigerant of R32.

単一冷媒では沸点が一箇所しかなく冷媒状態が液相から二相へ一気に変わるので、湾曲部における「非定常な冷媒通過音」の発生が顕著になると推測される。しかし、この冷凍装置では、湾曲部の流路面積が湾曲部より膨張機構側に在る部分の流路断面積よりも大きいので、単一冷媒を使用しても湾曲部における「非定常な冷媒通過音」の発生が防止される。その結果、Ｒ３２の単一冷媒を使用することが可能となり、Ｒ３２は圧損が低いので配管全体として細径化が促進される。 A single refrigerant has only one boiling point and the refrigerant state changes from a liquid phase to a two-phase at a stretch. Therefore, it is presumed that the occurrence of “unsteady refrigerant passing sound” in the curved portion becomes remarkable. However, in this refrigeration apparatus, since the flow passage area of the bending portion is larger than the flow passage cross-sectional area of the portion located on the expansion mechanism side from the bending portion, even if a single refrigerant is used, the “unsteady refrigerant in the bending portion” Generation of “passing sound” is prevented. As a result, it becomes possible to use a single refrigerant of R32, and since R32 has a low pressure loss, the diameter of the entire pipe is reduced.

本発明の第６観点に係る冷凍装置は、第１観点から第５観点のいずれか１つに係る冷凍装置であって、湾曲部の曲げ半径が３０ｍｍ以下である。 A refrigeration apparatus according to a sixth aspect of the present invention is the refrigeration apparatus according to any one of the first to fifth aspects, wherein the bending radius of the curved portion is 30 mm or less.

本発明の第１観点又は第６観点に係る冷凍装置では、「非定常な冷媒通過音」の発生する箇所の流路断面積を拡大して冷媒流速を遅くすることによって、湾曲部で発生する冷媒通過音を防止することができる。 In the refrigeration apparatus according to the first aspect or the sixth aspect of the present invention, the refrigerant is generated in the curved portion by enlarging the cross-sectional area of the passage where the “unsteady refrigerant passage noise” occurs to slow the refrigerant flow velocity. Refrigerant passage noise can be prevented.

本発明の第２観点に係る冷凍装置では、１本の管が２本の分岐管に分岐することによって、流路断面積の総和は分岐管手前の流路断面積よりも大きくなり、分岐管の径は手前の管径よりも小さくすることができるので曲げ加工が容易になる。 In the refrigeration apparatus according to the second aspect of the present invention, when one pipe branches into two branch pipes, the total cross-sectional area of the flow path becomes larger than the cross-sectional area of the flow path before the branch pipe. Since the diameter can be made smaller than the diameter of the tube on the front side, bending is facilitated.

本発明の第３観点に係る冷凍装置では、２本の分岐管を流れる冷媒を合流させずにそのまま蒸発器に入れてもよいが、再熱ドライなどを行う場合には冷媒は合流させて蒸発器に入れた方がよい。したがって、再熱ドライなどを行うタイプに有用である。 In the refrigeration apparatus according to the third aspect of the present invention, the refrigerant flowing through the two branch pipes may be put into the evaporator as it is without being merged. However, when performing reheat drying, the refrigerant is merged and evaporated. It is better to put it in a vessel. Therefore, it is useful for types that perform reheat drying and the like.

本発明の第４観点に係る冷凍装置では、湾曲部の流路面積が湾曲部より膨張機構側に在る部分の流路断面積よりも大きいので、単一冷媒を使用しても湾曲部における「非定常な冷媒通過音」の発生が防止される。 In the refrigeration apparatus according to the fourth aspect of the present invention, the flow passage area of the bending portion is larger than the flow passage cross-sectional area of the portion on the expansion mechanism side of the bending portion. Generation of “unsteady refrigerant passage noise” is prevented.

本発明の第５観点に係る冷凍装置では、湾曲部の流路面積が湾曲部より膨張機構側に在る部分の流路断面積よりも大きいので、単一冷媒を使用しても湾曲部における「非定常な冷媒通過音」の発生が防止される。その結果、Ｒ３２の単一冷媒を使用することが可能となり、Ｒ３２は圧損が低いので配管全体として細径化が促進される。 In the refrigeration apparatus according to the fifth aspect of the present invention, the flow passage area of the bending portion is larger than the flow passage cross-sectional area of the portion located on the expansion mechanism side from the bending portion. Generation of “unsteady refrigerant passage noise” is prevented. As a result, it becomes possible to use a single refrigerant of R32, and since R32 has a low pressure loss, the diameter of the entire pipe is reduced.

本発明の第１実施形態に係る冷凍装置の冷媒回路。The refrigerant circuit of the freezing apparatus which concerns on 1st Embodiment of this invention. 空調機の室内ユニットの斜視図。The perspective view of the indoor unit of an air conditioner. 室内ユニットから吸込パネルと前面グリルとを取り外した状態を示す正面図。The front view which shows the state which removed the suction panel and the front grille from the indoor unit. 従来の配管が接続された室内熱交換器の側面図。The side view of the indoor heat exchanger to which the conventional piping was connected. 「非定常な冷媒通過音」の解消対策後の配管が接続された室内熱交換器の側面図。The side view of the indoor heat exchanger to which the piping after the countermeasure against elimination of "unsteady refrigerant passage sound" was connected. 本発明の第２実施形態に係る冷凍装置において、「非定常な冷媒通過音」の解消対策後の配管が接続された室内熱交換器の側面図。The refrigeration apparatus which concerns on 2nd Embodiment of this invention WHEREIN: The side view of the indoor heat exchanger to which the pipe after the countermeasure against elimination of "unsteady refrigerant passage sound" was connected. 図４Ｃの湾曲部周辺の拡大斜視図。FIG. 4C is an enlarged perspective view around the curved portion of FIG. 4C. 圧力−エンタルピー線図上での蒸気圧縮冷凍サイクル。Vapor compression refrigeration cycle on pressure-enthalpy diagram.

以下、図面を参照しながら、本発明の実施形態について説明する。なお、以下の実施形態は、本発明の具体例であって、本発明の技術的範囲を限定するものではない。 Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are specific examples of the present invention and do not limit the technical scope of the present invention.

＜第１実施形態＞
（１）冷凍装置の構成
図１は、本発明の一実施形態に係る冷凍装置の冷媒回路である。図１において、この冷凍装置は、室外ユニット１と室内ユニット２とが連絡配管Ｌ１,Ｌ２を介して接続された空調機１００である。 <First Embodiment>
(1) Configuration of Refrigeration Device FIG. 1 is a refrigerant circuit of a refrigeration device according to an embodiment of the present invention. In FIG. 1, this refrigeration apparatus is an air conditioner 100 in which an outdoor unit 1 and an indoor unit 2 are connected via connecting pipes L1 and L2.

（１−１）室外ユニット１
室外ユニット１は、圧縮機１１と、四路切換弁１２と、室外熱交換器１３と、電動膨張弁１４とを備えている。室外ユニット１の圧縮機１１、四路切換弁１２、室外熱交換器１３、電動膨張弁１４、及び室内ユニット２の室内熱交換器１５が順に接続されることによって冷媒回路が構成されている。 (1-1) Outdoor unit 1
The outdoor unit 1 includes a compressor 11, a four-way switching valve 12, an outdoor heat exchanger 13, and an electric expansion valve 14. The refrigerant circuit is configured by sequentially connecting the compressor 11 of the outdoor unit 1, the four-way switching valve 12, the outdoor heat exchanger 13, the electric expansion valve 14, and the indoor heat exchanger 15 of the indoor unit 2.

（１−１−１）圧縮機１１
圧縮機１１は容量可変式圧縮機であり、インバータにより回転数が制御される。本実施形態において、圧縮機１１は１台のみであるが、これに限定されず、室内ユニット２の接続台数等に応じて、２台以上の圧縮機が並列に接続されていても良い。 (1-1-1) Compressor 11
The compressor 11 is a variable capacity compressor, and the rotation speed is controlled by an inverter. In the present embodiment, the number of the compressors 11 is only one. However, the present invention is not limited to this, and two or more compressors may be connected in parallel according to the number of indoor units 2 connected.

（１−１−２）四路切換弁１２
四路切換弁１２は、冷媒の流れの方向を切り換える弁である。冷房運転時、四路切換弁１２は圧縮機１１の吐出側と室外熱交換器１３のガス側とを接続するとともに圧縮機１１の吸入側（具体的には、アキュムレータ１６）とガス冷媒連絡配管Ｌ２側とを接続する（冷房運転状態：図１の四路切換弁１２の実線を参照）。その結果、室外熱交換器１３は冷媒の凝縮器として、室内熱交換器１５は冷媒の蒸発器として機能する。 (1-1-2) Four-way selector valve 12
The four-way switching valve 12 is a valve that switches the direction of the refrigerant flow. During the cooling operation, the four-way switching valve 12 connects the discharge side of the compressor 11 and the gas side of the outdoor heat exchanger 13 and at the same time the suction side (specifically, accumulator 16) of the compressor 11 and the gas refrigerant communication pipe. L2 side is connected (cooling operation state: refer to the solid line of the four-way switching valve 12 in FIG. 1). As a result, the outdoor heat exchanger 13 functions as a refrigerant condenser, and the indoor heat exchanger 15 functions as a refrigerant evaporator.

暖房運転時、四路切換弁１２は、圧縮機１１の吐出側とガス冷媒連絡配管Ｌ２側とを接続するとともに圧縮機１１の吸入側と室外熱交換器１３のガス側とを接続する（暖房運転状態：図１の四路切換弁１２の破線を参照）。その結果、室内熱交換器１５は冷媒の凝縮器として、室外熱交換器１３は冷媒の蒸発器として機能する。 During the heating operation, the four-way switching valve 12 connects the discharge side of the compressor 11 and the gas refrigerant communication pipe L2 side, and connects the suction side of the compressor 11 and the gas side of the outdoor heat exchanger 13 (heating). Operation state: (Refer to the broken line of the four-way switching valve 12 in FIG. 1). As a result, the indoor heat exchanger 15 functions as a refrigerant condenser, and the outdoor heat exchanger 13 functions as a refrigerant evaporator.

（１−１−３）室外熱交換器１３
室外熱交換器１３は、クロスフィン式のフィン・アンド・チューブ型熱交換器である。但し、これに限定されず、他の型式の熱交換器であっても良い。 (1-1-3) Outdoor heat exchanger 13
The outdoor heat exchanger 13 is a cross-fin type fin-and-tube heat exchanger. However, the present invention is not limited to this, and other types of heat exchangers may be used.

室外熱交換器１３は、冷房運転時には冷媒の凝縮器として機能し、暖房運転時には冷媒の蒸発器として機能する。室外熱交換器１３は、そのガス側が四路切換弁１２に接続され、その液側が電動膨張弁１４に接続されている。 The outdoor heat exchanger 13 functions as a refrigerant condenser during the cooling operation, and functions as a refrigerant evaporator during the heating operation. The outdoor heat exchanger 13 has a gas side connected to the four-way switching valve 12 and a liquid side connected to the electric expansion valve 14.

（１−１−４）電動膨張弁１４
電動膨張弁１４は、冷媒回路内を流れる冷媒の圧力や流量等の調節を行う。電動膨張弁１４は、冷房運転時の冷媒回路における冷媒の流れ方向において室外熱交換器１３の下流側に配置されている。 (1-1-4) Electric expansion valve 14
The electric expansion valve 14 adjusts the pressure and flow rate of the refrigerant flowing in the refrigerant circuit. The electric expansion valve 14 is disposed downstream of the outdoor heat exchanger 13 in the refrigerant flow direction in the refrigerant circuit during the cooling operation.

（１−１−５）室外ファン１７
室外ファン１７は、吸入した室外空気を室外熱交換器１３に送風して冷媒と熱交換させる。室外ファン１７は、室外熱交換器１３に送風する際の風量を可変することができる。室外ファン１７は、プロペラファン等であり、ＤＣファンモータ等からなるモータによって駆動される。 (1-1-5) Outdoor fan 17
The outdoor fan 17 blows the sucked outdoor air to the outdoor heat exchanger 13 to exchange heat with the refrigerant. The outdoor fan 17 can vary the amount of air that is blown to the outdoor heat exchanger 13. The outdoor fan 17 is a propeller fan or the like, and is driven by a motor including a DC fan motor or the like.

（１−１−６）液側閉鎖弁２１及びガス側閉鎖弁２２
液側閉鎖弁２１及びガス側閉鎖弁２２は、液冷媒連絡配管Ｌ１及びガス冷媒連絡配管Ｌ２との接続口に設けられる弁である。 (1-1-6) Liquid side closing valve 21 and gas side closing valve 22
The liquid side shutoff valve 21 and the gas side shutoff valve 22 are valves provided at connection ports with the liquid refrigerant communication pipe L1 and the gas refrigerant communication pipe L2.

液側閉鎖弁２１は、冷房運転時の冷媒回路における冷媒の流れ方向において電動膨張弁１４の下流側であって液冷媒連絡配管Ｌ１の上流側に配置されている。ガス側閉鎖弁２２は、四路切換弁１２に接続されている。液側閉鎖弁２１及びガス側閉鎖弁２２は、冷媒の通過を遮断することができる。 The liquid side closing valve 21 is disposed downstream of the electric expansion valve 14 and upstream of the liquid refrigerant communication pipe L1 in the refrigerant flow direction in the refrigerant circuit during the cooling operation. The gas side closing valve 22 is connected to the four-way switching valve 12. The liquid side closing valve 21 and the gas side closing valve 22 can block the passage of the refrigerant.

（１−１−７）加湿ユニット４２
また、室外ユニット１は加湿ユニット４２をさらに備えている。加湿ユニット４２は、暖房運転時等において室内が乾燥する場合、加湿空気を加湿ホース４１及びダクト部４０を介して室内に供給する。 (1-1-7) Humidification unit 42
The outdoor unit 1 further includes a humidification unit 42. The humidifying unit 42 supplies humidified air to the room via the humidifying hose 41 and the duct part 40 when the room is dried during heating operation or the like.

加湿ユニット４２は、ゼオライト等の吸着材を用いて室外空気から水分を吸着し、その吸着剤に吸着した水分により室外空気を加湿した後、加湿された室外空気を室内ユニット２に供給するものである。なお、加湿ユニット４２の構成はこれに限らず、水道などの給水手段により補給される水を用いて、加湿された空気を室内に供給する加湿ユニットなどでもよい。 The humidifying unit 42 adsorbs moisture from the outdoor air using an adsorbent such as zeolite, humidifies the outdoor air with the moisture adsorbed on the adsorbent, and then supplies the humidified outdoor air to the indoor unit 2. is there. The configuration of the humidifying unit 42 is not limited to this, and may be a humidifying unit that supplies humidified air indoors using water replenished by water supply means such as tap water.

（１−２）室内ユニット２
図２は、空調機１００の室内ユニット２の斜視図である。図１及び図２において、室内ユニット２は、本体ケーシング３０と、室内熱交換器１５と、室内ファン１８とを備えている。 (1-2) Indoor unit 2
FIG. 2 is a perspective view of the indoor unit 2 of the air conditioner 100. 1 and 2, the indoor unit 2 includes a main body casing 30, an indoor heat exchanger 15, and an indoor fan 18.

（１−２−１）本体ケーシング３０
本体ケーシング３０は、底フレーム３１と、前面グリル３２と、吸込パネル３３とから成る。 (1-2-1) Main body casing 30
The main casing 30 includes a bottom frame 31, a front grill 32, and a suction panel 33.

底フレーム３１は、略長方形状で、室内の壁面に後面側が取り付けられる。前面グリル３２は、底フレーム３１の前面側に取り付けられ、前面に略長方形状の開口部（図示せず）を有している。吸込パネル３３は、前面グリル３２の開口部を覆うように取り付けられている。 The bottom frame 31 has a substantially rectangular shape, and the rear surface side is attached to the wall surface of the room. The front grill 32 is attached to the front side of the bottom frame 31 and has a substantially rectangular opening (not shown) on the front. The suction panel 33 is attached so as to cover the opening of the front grill 32.

前面グリル３２は、上部に上側吹出口３２aを有し、下部に下側吹出口３２bを有している。上側吹出口３２aにはフラップ３４が設けられている。フラップ３４は、冷房運転および暖房運転時に回動して、上側吹出口３２aからの冷風,温風を前方かつ斜め上方に偏向し、運転停止時には上側吹出口３２aを覆う。 The front grill 32 has an upper air outlet 32a at the upper portion and a lower air outlet 32b at the lower portion. A flap 34 is provided at the upper outlet 32a. The flap 34 rotates during the cooling operation and the heating operation, deflects the cool air and the warm air from the upper air outlet 32a forward and obliquely upward, and covers the upper air outlet 32a when the operation is stopped.

また、上記吸込パネル３３の上側には上側吸込口３３aが設けられ、また吸込パネル３３の下側には下側吸込口３３bが設けられ、さらに吸込パネル３３の左右の側面には側方吸込口３３c(図２では右側のみを示す)が設けられている。 An upper suction port 33 a is provided above the suction panel 33, a lower suction port 33 b is provided below the suction panel 33, and side suction ports are provided on the left and right side surfaces of the suction panel 33. 33c (only the right side is shown in FIG. 2) is provided.

図３は、室内ユニット２から吸込パネル３３と前面グリル３２とを取り外した状態を示す正面図である。図３において、底フレーム３１の前面側に略平面形状の室内熱交換器１５が配置され、その裏面側に室内ファン１８が配置されている。 FIG. 3 is a front view showing a state in which the suction panel 33 and the front grill 32 are removed from the indoor unit 2. In FIG. 3, a substantially planar indoor heat exchanger 15 is disposed on the front side of the bottom frame 31, and an indoor fan 18 is disposed on the back side thereof.

また、底フレーム３１の右側面近傍の側室Ｓには、連絡配管Ｌ１が接続される第１配管接続部６１と連絡配管Ｌ２が接続される第２配管接続部６２と設けられている。両連絡配管Ｌ１，Ｌ２は、底フレーム３１の左側面近傍かつ下側に背面側から加湿ホース４１と共に入り、底フレーム３１内の下側を左から右に向かって導かれて配管接続部６１，６２に接続される。 The side chamber S in the vicinity of the right side surface of the bottom frame 31 is provided with a first pipe connecting part 61 to which the connecting pipe L1 is connected and a second pipe connecting part 62 to which the connecting pipe L2 is connected. Both the connecting pipes L1 and L2 enter the vicinity of the left side of the bottom frame 31 and the lower side together with the humidifying hose 41 from the back side, and the lower side in the bottom frame 31 is led from the left to the right to be connected to the pipe connecting part 61, 62.

（１−２−２）室内熱交換器１５
室内熱交換器１５は、伝熱管と多数のフィンとにより構成されたクロスフィン式のフィン・アンド・チューブ型熱交換器である。室内熱交換器１５は、冷房運転時には冷媒の蒸発器として機能して室内空気を冷却し、暖房運転時には冷媒の凝縮器として機能して室内空気を加熱する。 (1-2-2) Indoor heat exchanger 15
The indoor heat exchanger 15 is a fin-and-tube heat exchanger of a cross fin type configured by heat transfer tubes and a large number of fins. The indoor heat exchanger 15 functions as a refrigerant evaporator during cooling operation to cool the room air, and functions as a refrigerant condenser during heating operation to heat the room air.

なお、室内熱交換器１５は、クロスフィン式のフィン・アンド・チューブ型熱交換器に限定されるものではなく、他の型式の熱交換器であっても良い。 The indoor heat exchanger 15 is not limited to a cross fin type fin-and-tube heat exchanger, but may be another type of heat exchanger.

（１−２−３）室内ファン１８
室内ファン１８は、前面側から空気を吸い込んで半径方向外向に吹き出すターボファンである。室内ファン１８の稼動によって、室内ユニット２は前面側から内部に室内空気を吸入し、室内熱交換器１５において冷媒と熱交換させた後に、供給空気として室内に供給する。また、室内ファン１８は、室内熱交換器１５に供給する空気の風量を所定風量範囲において変更することができる。 (1-2-3) Indoor fan 18
The indoor fan 18 is a turbo fan that sucks air from the front side and blows it outward in the radial direction. With the operation of the indoor fan 18, the indoor unit 2 sucks indoor air into the interior from the front side, and after exchanging heat with the refrigerant in the indoor heat exchanger 15, supplies the indoor air as supply air. Moreover, the indoor fan 18 can change the air volume of the air supplied to the indoor heat exchanger 15 within a predetermined air volume range.

（１−２−４）ダクト部４０
室内ユニット２は、ダクト部４０をさらに備えている。ダクト部４０は、底フレーム３１の左側面近傍かつ下側に配置されている。ダクト部４０は、開口４０ａと、ホース接続部４０ｂとを有している。開口４０ａは、略長方形状であり、後面側斜め上方に向かって開口する。ホース接続部４０ｂには、加湿ホース４１が繋がれる。加湿ユニット４２で生成された加湿空気は、加湿ホース４１経由してダクト部４０に搬送され、室内に供給される。 (1-2-4) Duct portion 40
The indoor unit 2 further includes a duct portion 40. The duct portion 40 is disposed near and below the left side surface of the bottom frame 31. The duct part 40 has an opening 40a and a hose connection part 40b. The opening 40a has a substantially rectangular shape and opens obliquely upward on the rear side. A humidifying hose 41 is connected to the hose connecting portion 40b. Humidified air generated by the humidifying unit 42 is conveyed to the duct portion 40 via the humidifying hose 41 and supplied indoors.

（２）空調機１００の動作
（２−１）暖房運転
暖房運転時、四路切換弁１２は、圧縮機１１の吐出側と室内熱交換器１５のガス側とを接続し、且つ圧縮機１１の吸入側と室外熱交換器１３のガス側とを接続する（図１の破線で示される状態）。 (2) Operation of the air conditioner 100 (2-1) Heating operation During the heating operation, the four-way switching valve 12 connects the discharge side of the compressor 11 and the gas side of the indoor heat exchanger 15, and the compressor 11. Are connected to the gas side of the outdoor heat exchanger 13 (indicated by the broken line in FIG. 1).

また、電動膨張弁１４の開度は、室外熱交換器１３に流入する冷媒を室外熱交換器１３において蒸発させることが可能な圧力まで減圧するように調節される。液側閉鎖弁２１及びガス側閉鎖弁２２は開状態である。 The opening degree of the electric expansion valve 14 is adjusted so that the refrigerant flowing into the outdoor heat exchanger 13 is reduced to a pressure at which the outdoor heat exchanger 13 can evaporate. The liquid side closing valve 21 and the gas side closing valve 22 are open.

この冷媒回路の状態で、圧縮機１１、室外ファン１７および室内ファン１８を運転すると、低圧のガス冷媒は、圧縮機１１に吸入されて圧縮されて高圧のガス冷媒となり、四路切換弁１２、ガス側閉鎖弁２２およびガス冷媒連絡配管Ｌ２を経由して、室内ユニット２に送られる。 When the compressor 11, the outdoor fan 17 and the indoor fan 18 are operated in the state of this refrigerant circuit, the low-pressure gas refrigerant is sucked into the compressor 11 and compressed to become a high-pressure gas refrigerant. It is sent to the indoor unit 2 via the gas side closing valve 22 and the gas refrigerant communication pipe L2.

室内ユニット２に送られた高圧のガス冷媒は、室内熱交換器１５において、室内空気と熱交換を行って凝縮して高圧の液冷媒となり、液冷媒連絡配管Ｌ１を経由して室外ユニット１に送られる。 The high-pressure gas refrigerant sent to the indoor unit 2 is condensed by exchanging heat with indoor air in the indoor heat exchanger 15, and becomes a high-pressure liquid refrigerant, and is transferred to the outdoor unit 1 via the liquid refrigerant communication pipe L1. Sent.

液冷媒は、液側閉鎖弁２１を通過して、電動膨張弁１４に入る。液冷媒は、電動膨張弁１４で減圧された後に、室外熱交換器１３に流入する。室外熱交換器１３に流入した低圧の気液二相状態の冷媒は、室外ファン１７によって供給される室外空気と熱交換を行って蒸発して低圧のガス冷媒となり、四路切換弁１２を経由してアキュムレータ１６に流入する。アキュムレータ１６に流入した低圧のガス冷媒は、再び、圧縮機１１に吸入される。 The liquid refrigerant passes through the liquid side closing valve 21 and enters the electric expansion valve 14. The liquid refrigerant is decompressed by the electric expansion valve 14 and then flows into the outdoor heat exchanger 13. The low-pressure gas-liquid two-phase refrigerant flowing into the outdoor heat exchanger 13 exchanges heat with the outdoor air supplied by the outdoor fan 17 to evaporate into a low-pressure gas refrigerant, and passes through the four-way switching valve 12. And flows into the accumulator 16. The low-pressure gas refrigerant that has flowed into the accumulator 16 is again sucked into the compressor 11.

（２−２）冷房運転
冷房運転時、四路切換弁１２は、圧縮機１１の吐出側と室外熱交換器１３のガス側とを接続し、且つ圧縮機１１の吸入側と室内熱交換器１５のガス側とを接続する（図１の実線で示される状態）。 (2-2) Cooling Operation During the cooling operation, the four-way switching valve 12 connects the discharge side of the compressor 11 and the gas side of the outdoor heat exchanger 13, and the suction side of the compressor 11 and the indoor heat exchanger. 15 gas sides are connected (state shown by a solid line in FIG. 1).

また、液側閉鎖弁２１及びガス側閉鎖弁２２は開状態である。電動膨張弁１４の開度は、室内熱交換器１５の冷媒出口における冷媒の過熱度ＳＨが過熱度目標値で一定になるように調節される。 Moreover, the liquid side closing valve 21 and the gas side closing valve 22 are open. The opening degree of the electric expansion valve 14 is adjusted so that the superheat degree SH of the refrigerant at the refrigerant outlet of the indoor heat exchanger 15 becomes constant at the superheat degree target value.

この冷媒回路の状態で、圧縮機１１、室外ファン１７および室内ファン１８を運転すると、低圧のガス冷媒は、圧縮機１１に吸入されて圧縮されて高圧のガス冷媒となる。その後、高圧のガス冷媒は、四路切換弁１２を経由して室外熱交換器１３に送られて、室外ファン１７によって供給される室外空気と熱交換を行って凝縮して高圧の液冷媒となる。そして、この高圧の液冷媒は、電動膨張弁１４で減圧された後、液側閉鎖弁２１および液冷媒連絡配管Ｌ１を経由して、室内ユニット２に送られる。 When the compressor 11, the outdoor fan 17 and the indoor fan 18 are operated in the state of this refrigerant circuit, the low-pressure gas refrigerant is sucked into the compressor 11 and compressed to become a high-pressure gas refrigerant. Thereafter, the high-pressure gas refrigerant is sent to the outdoor heat exchanger 13 via the four-way switching valve 12, exchanges heat with the outdoor air supplied by the outdoor fan 17, and is condensed to form a high-pressure liquid refrigerant. Become. The high-pressure liquid refrigerant is depressurized by the electric expansion valve 14 and then sent to the indoor unit 2 via the liquid-side closing valve 21 and the liquid refrigerant communication pipe L1.

この室内ユニット２に送られた低圧の冷媒は、気液二相状態の冷媒となって室内熱交換器１５に入り、室内熱交換器１５において室内空気と熱交換を行って蒸発して低圧のガス冷媒となる。 The low-pressure refrigerant sent to the indoor unit 2 becomes a refrigerant in a gas-liquid two-phase state, enters the indoor heat exchanger 15, performs heat exchange with indoor air in the indoor heat exchanger 15, evaporates, and is low-pressure It becomes a gas refrigerant.

この低圧のガス冷媒は、ガス冷媒連絡配管Ｌ２を経由して室外ユニット１に送られ、ガス側閉鎖弁２２及び四路切換弁１２を経由して、アキュムレータ１６に流入する。そして、アキュムレータ１６に流入した低圧のガス冷媒は、再び、圧縮機１１に吸入される。 This low-pressure gas refrigerant is sent to the outdoor unit 1 via the gas refrigerant communication pipe L2, and flows into the accumulator 16 via the gas-side closing valve 22 and the four-way switching valve 12. Then, the low-pressure gas refrigerant that has flowed into the accumulator 16 is again sucked into the compressor 11.

このように、空調機１００では、室外熱交換器１３を冷媒の凝縮器として、かつ、室内熱交換器１５を冷媒の蒸発器として機能させる冷房運転を行うことができる。 Thus, the air conditioner 100 can perform a cooling operation in which the outdoor heat exchanger 13 functions as a refrigerant condenser and the indoor heat exchanger 15 functions as a refrigerant evaporator.

（３）冷房運転時の「冷媒通過音」について
図４Ａは、従来の配管が接続された室内熱交換器１５の側面図である。図４Ａにおいて、配管５０は電動膨張弁１４と室内熱交換器１５とを結ぶ配管であるが、本図では、連絡配管Ｌ１が接続される第１配管接続部６１から室内熱交換器１５の冷媒入口１５ａまでの部分を記載している。 (3) “Refrigerant passing sound” during cooling operation FIG. 4A is a side view of the indoor heat exchanger 15 to which a conventional pipe is connected. In FIG. 4A, the pipe 50 is a pipe connecting the electric expansion valve 14 and the indoor heat exchanger 15, but in this figure, the refrigerant of the indoor heat exchanger 15 starts from the first pipe connecting portion 61 to which the connecting pipe L1 is connected. The portion up to the inlet 15a is shown.

配管５０は、第１配管接続部６１から鉛直上方に延びた後、逆Ｕ字状に方向転換する。説明の便宜上、この区間を第１区間５１という。 The pipe 50 extends vertically upward from the first pipe connection portion 61 and then changes its direction into an inverted U shape. For convenience of explanation, this section is referred to as a first section 51.

また、配管５０は、第１区間５１の終端から第１距離だけ鉛直下方に延びた後、所定曲率で水平方向に方向転換して、第１距離より短い第２距離だけ水平に延び、さらに所定曲率で斜め下方に方向転換してから、第１距離より長い第３距離だけ斜め下方に延びて室内熱交換器１５の冷媒入口１５ａに到達する。説明の便宜上、この区間を第２区間５２という。 The pipe 50 extends vertically downward from the end of the first section 51 by a first distance, then changes direction horizontally with a predetermined curvature, and extends horizontally by a second distance shorter than the first distance. After turning diagonally downward with the curvature, it extends obliquely downward by a third distance longer than the first distance and reaches the refrigerant inlet 15a of the indoor heat exchanger 15. For convenience of explanation, this section is referred to as a second section 52.

さらに、第２区間５２のうち第１距離だけ鉛直下方に延びる部分を鉛直部５２ａ、所定曲率で水平方向に方向転換する部分を第１湾曲部５２ｄ、第２距離だけ水平に延びる部分を水平部５２ｅ、水平部５２ｅの終端から所定曲率で斜め下方に方向転換する部分を第２湾曲部５２ｆ、第３距離だけ斜め下方に延びる部分を傾斜部５２ｇという。なお、第１区間５１及び第２区間５２の管内径は６．３５ｍｍである。 Further, the portion of the second section 52 that extends vertically downward by the first distance is the vertical portion 52a, the portion that changes the direction in the horizontal direction with a predetermined curvature is the first curved portion 52d, and the portion that extends horizontally by the second distance is the horizontal portion. 52e, a portion that turns obliquely downward with a predetermined curvature from the end of the horizontal portion 52e is referred to as a second curved portion 52f, and a portion that extends obliquely downward by a third distance is referred to as an inclined portion 52g. The tube inner diameters of the first section 51 and the second section 52 are 6.35 mm.

冷房運転時、電動膨張弁１４を通過した冷媒は、配管５０を通って室内熱交換器１５の下部から室内熱交換器１５内に流入する。配管５０は第１湾曲部５２ｄ及び第２湾曲部５２ｆを有しているが、冷媒の流れを鉛直下方から水平方向に転換する第１湾曲部５２ｄで「非定常な冷媒通過音」が発生することがある。 During the cooling operation, the refrigerant that has passed through the electric expansion valve 14 flows into the indoor heat exchanger 15 through the pipe 50 from the lower portion of the indoor heat exchanger 15. Although the pipe 50 has the first curved portion 52d and the second curved portion 52f, the “unsteady refrigerant passing sound” is generated in the first curved portion 52d that changes the flow of the refrigerant from the vertically downward direction to the horizontal direction. Sometimes.

（３−１）「非定常な冷媒通過音」の発生メカニズム
以下、図６の「圧力−エンタルピー線図上での蒸気圧縮冷凍サイクル」を参照しながら、「非定常な冷媒通過音」の発生メカニズムの推定を行う。図６において、冷凍サイクルのＰ１点−Ｐ２点はガス冷媒の圧縮過程、Ｐ２点−Ｐ３点は高温高圧ガス冷媒の凝縮過程、Ｐ３点−Ｐ４点は液冷媒の減圧過程、Ｐ４点−Ｐ１点は液冷媒の蒸発過程を表している。 (3-1) Generation Mechanism of “Unsteady Refrigerant Passing Sound” Hereinafter, with reference to “Vapor Compression Refrigeration Cycle on Pressure-Enthalpy Diagram” in FIG. Estimate the mechanism. In FIG. 6, points P1 to P2 of the refrigeration cycle are gas refrigerant compression processes, points P2 to P3 are condensation processes of high-temperature and high-pressure gas refrigerants, points P3 to P4 are pressure reduction processes of liquid refrigerant, and points P4 to P1. Represents the evaporation process of the liquid refrigerant.

減圧過程（Ｐ３点−Ｐ４点）は、液冷媒が電動膨張弁１４で減圧されて必要な蒸発圧力まで下がる工程であり、電動膨張弁１４で減圧された冷媒は液相から液冷媒とガス冷媒とが混ざる二相状態となる。 The depressurization process (P3 point-P4 point) is a process in which the liquid refrigerant is depressurized by the electric expansion valve 14 and drops to a necessary evaporation pressure. The refrigerant depressurized by the electric expansion valve 14 is liquid refrigerant and gas refrigerant from the liquid phase. It becomes a two-phase state where and are mixed.

この液相から二相状態に変わるポイントは、通常はＰ４点の近傍に存在するのであるが、非定常的に下流側に遷移することがある。その下流側に例えば第１湾曲部５２ｄが存在し、且つ液相から二相状態に変わるポイントが偶然に第１湾曲部５２ｄに遷移したときに「非定常な冷媒通過音」が発生すると推測される。 The point at which the liquid phase changes to the two-phase state usually exists in the vicinity of the point P4, but may transit unsteadily to the downstream side. For example, when the first curved portion 52d exists on the downstream side and the point at which the liquid phase changes to the two-phase state accidentally transitions to the first curved portion 52d, it is estimated that an “unsteady refrigerant passing sound” is generated. The

また、上記「非定常な冷媒通過音」の発生現象は、Ｒ３２では発見されているがＲ４１０Ａでは発見されていない。これは、微妙に異なる複数の沸点を有するＲ４１０Ａのような三種混合冷媒は徐々に冷媒状態が変わっていくので「非定常な冷媒通過音」の発生が抑制されるのに対し、Ｒ３２のような単一冷媒では沸点が一箇所しかなく冷媒状態が一気に変わるので、「非定常な冷媒通過音」の発生が顕著になると推測される。 In addition, the occurrence phenomenon of the “unsteady refrigerant passing sound” is found in R32 but not in R410A. This is because the three-type mixed refrigerant such as R410A having a plurality of slightly different boiling points gradually changes in refrigerant state, so that the generation of “unsteady refrigerant passage noise” is suppressed, whereas the refrigerant like R32 Since the single refrigerant has only one boiling point and the refrigerant state changes at a stroke, it is assumed that the occurrence of “unsteady refrigerant passage noise” becomes remarkable.

（３−２）「非定常な冷媒通過音」を解消する配管構成
図４Ａにおける第２区間５２の第１湾曲部５２ｄで発生する「非定常な冷媒通過音」は冷媒の流速が速いほど発生し易い傾向にあることが出願人によって確認されており、「非定常な冷媒通過音」の発生する箇所の流路断面積を拡大して冷媒流速を遅くすることによって、湾曲部で発生する「非定常な冷媒通過音」を防止することができる。 (3-2) Piping Configuration to Eliminate “Unsteady Refrigerant Passing Sound” “Unsteady refrigerant passing sound” generated at the first curved portion 52d of the second section 52 in FIG. It has been confirmed by the applicant that it tends to be easy to perform, and by expanding the flow path cross-sectional area at the location where the “unsteady refrigerant passing sound” occurs and slowing the refrigerant flow velocity, An “unsteady refrigerant passing sound” can be prevented.

図４Ｂは、「非定常な冷媒通過音」の解消対策後の配管が接続された室内熱交換器１５の側面図である。図４Ｂにおいて、第２区間５３は、図４Ａにおける第２区間５２の第１湾曲部５２ｄの流路断面積がほぼ２倍になるように管内径を変更した仕様（例えば、内径６．３５ｍｍを内径９ｍｍへ変更）に置き換えられている。 FIG. 4B is a side view of the indoor heat exchanger 15 to which the pipe after elimination of the “unsteady refrigerant passing sound” is connected. 4B, the second section 53 has a specification (for example, an inner diameter of 6.35 mm) in which the pipe inner diameter is changed so that the flow path cross-sectional area of the first curved portion 52d of the second section 52 in FIG. 4A is almost doubled. The inner diameter is changed to 9 mm).

第２区間５３は、通常管鉛直部５３ａ、第１ジョイント部５３ｂ、大径管鉛直部５３ｃ、大径管第１湾曲部５３ｄ、大径管水平部５３ｅ、大径管第２湾曲部５３ｆ、大径管傾斜部５３ｇ、第２ジョイント部５３ｈ、及び通常管傾斜部５３ｉを有している。 The second section 53 includes a normal pipe vertical part 53a, a first joint part 53b, a large-diameter pipe vertical part 53c, a large-diameter pipe first bending part 53d, a large-diameter pipe horizontal part 53e, a large-diameter pipe second bending part 53f, It has a large-diameter pipe inclined part 53g, a second joint part 53h, and a normal pipe inclined part 53i.

（３−２−１）通常管鉛直部５３ａ
通常管鉛直部５３ａは、第１区間５１と同じ管内径のまま所定距離だけ鉛直下方に延びる部分である。 (3-2-1) Normal pipe vertical portion 53a
The normal pipe vertical portion 53a is a portion that extends vertically downward by a predetermined distance with the same pipe inner diameter as that of the first section 51.

（３−２−２）第１ジョイント部５３ｂ
第１ジョイント部５３ｂは、通常管鉛直部５３ａの終端と内径が通常管鉛直部５３ａの内径よりも大きい大径管とを繋ぐ部分である。 (3-2-2) First joint portion 53b
The 1st joint part 53b is a part which connects the terminal of the normal pipe vertical part 53a, and the large diameter pipe whose internal diameter is larger than the internal diameter of the normal pipe vertical part 53a.

（３−２−３）大径管鉛直部５３ｃ
大径管鉛直部５３ｃは、上記大径管のうち第１ジョイント部５３ｂから鉛直下方に所定距離だけ延びる部分である。 (3-2-3) Large-diameter pipe vertical portion 53c
The large-diameter pipe vertical portion 53c is a portion of the large-diameter pipe that extends a predetermined distance vertically downward from the first joint portion 53b.

（３−２−４）大径管第１湾曲部５３ｄ
大径管第１湾曲部５３ｄは、大径管鉛直部５３ｃを所定曲率で水平方向に方向転換する部分である。なお、湾曲部の曲げ半径は３０ｍｍ以下であり、２０ｍｍが望ましい。 (3-2-4) Large-diameter pipe first bending portion 53d
The large-diameter tube first bending portion 53d is a portion that changes the direction of the large-diameter tube vertical portion 53c in the horizontal direction with a predetermined curvature. The bending radius of the curved portion is 30 mm or less, and preferably 20 mm.

（３−２−５）大径管水平部５３ｅ
大径管水平部５３ｅは、大径管第１湾曲部５３ｄの終端から所定距離だけ水平に延びる部分である。 (3-2-5) Large diameter pipe horizontal portion 53e
The large-diameter tube horizontal portion 53e is a portion that extends horizontally by a predetermined distance from the end of the large-diameter tube first bending portion 53d.

（３−２−６）大径管第２湾曲部５３ｆ
大径管第２湾曲部５３ｆは、大径管水平部５３ｅの終端から所定曲率で斜め下方に方向転換する部分である。 (3-2-6) Large-diameter pipe second bending portion 53f
The large-diameter tube second bending portion 53f is a portion that turns obliquely downward at a predetermined curvature from the end of the large-diameter tube horizontal portion 53e.

（３−２−７）大径管傾斜部５３ｇ
大径管傾斜部５３ｇは、大径管第２湾曲部５３ｆの終端から所定距離だけ斜め下方に延びる部分である。 (3-2-7) Large diameter pipe inclined part 53g
The large-diameter tube inclined portion 53g is a portion that extends obliquely downward by a predetermined distance from the end of the large-diameter tube second bending portion 53f.

（３−２−８）第２ジョイント部５３ｈ
第２ジョイント部５３ｈは、大径管傾斜部５３ｇの終端と通常管傾斜部５３１ｉとを繋ぐ部分である。 (3-2-8) Second joint portion 53h
The second joint part 53h is a part that connects the end of the large-diameter pipe inclined part 53g and the normal pipe inclined part 531i.

（３−２−９）通常管傾斜部５３ｉ
通常管傾斜部５３ｉは、内径が第１区間５１の内径と同じで、第２ジョイント部５３ｈと室内熱交換器１５の冷媒入口を結ぶ部分である。 (3-2-9) Normal pipe inclined portion 53i
The normal pipe inclined portion 53 i has an inner diameter that is the same as the inner diameter of the first section 51 and is a portion that connects the second joint portion 53 h and the refrigerant inlet of the indoor heat exchanger 15.

（３−３）作用と効果
電動膨張弁１４を通過した冷媒は、第１配管接続部６１から配管５０の第１区間を通って第２区間５３に入る。第２区間５３では、通常管鉛直部５３ａを通過した冷媒は、第１ジョイント部５３ｂに入り、その後は流路断面積の大きい大径管鉛直部５３ｃ、大径管第１湾曲部５３ｄ、大径管水平部５３ｅ、大径管第２湾曲部５３ｆ、及び大径管傾斜部５３ｇの順に流れ、第２ジョイント部５３ｈに到達する。第２ジョイント部５３ｈを出た冷媒は通常管傾斜部５３ｉを通って室内熱交換器１５の冷媒入口１５ａに流入する。 (3-3) Action and Effect The refrigerant that has passed through the electric expansion valve 14 enters the second section 53 from the first pipe connection 61 through the first section of the pipe 50. In the second section 53, the refrigerant that has passed through the normal pipe vertical part 53a enters the first joint part 53b, and thereafter, the large-diameter pipe vertical part 53c, the large-diameter pipe first bending part 53d, and the large-diameter pipe cross-sectional area are large. The diameter pipe horizontal part 53e, the large diameter pipe second bending part 53f, and the large diameter pipe inclined part 53g flow in this order and reach the second joint part 53h. The refrigerant that has exited the second joint portion 53h flows into the refrigerant inlet 15a of the indoor heat exchanger 15 through the normal pipe inclined portion 53i.

大径管第１湾曲部５３ｄの流路断面積は通常管鉛直部５３ａの流路断面積の２倍程度であり、そこを通過する冷媒の流速は、図４Ａにおける第２区間５２の第１湾曲部５２ｄを通過する冷媒の流速の１／２程度になっており、「非定常な冷媒通過音」の発生が防止される。 The flow path cross-sectional area of the large-diameter pipe first curved portion 53d is about twice the flow path cross-sectional area of the normal pipe vertical portion 53a, and the flow rate of the refrigerant passing therethrough is the first flow rate in the second section 52 in FIG. 4A. This is about ½ of the flow velocity of the refrigerant passing through the curved portion 52d, and the generation of “unsteady refrigerant passage noise” is prevented.

（４）第１実施形態の特徴
（４−１）
空調機１００では、電動膨張弁１４と室内熱交換器１５とを結ぶ配管５０が、室内ユニット２内に配される大径管第１湾曲部５３ｄを有している。大径管第１湾曲部５３ｄの流路面積は、その配管５０のうち大径管第１湾曲部５３ｄより電動膨張弁１４側に在る部分（例えば、第１区間５１）の流路断面積よりも大きいので、冷媒流速を遅くなり、大径管第１湾曲部５３ｄで発生する「非定常な冷媒通過音」が防止される。 (4) Features of the first embodiment (4-1)
In the air conditioner 100, the pipe 50 that connects the electric expansion valve 14 and the indoor heat exchanger 15 has a large-diameter pipe first bending portion 53 d that is arranged in the indoor unit 2. The flow path area of the large-diameter pipe first bending portion 53d is the flow-path cross-sectional area of the portion of the pipe 50 that is closer to the electric expansion valve 14 than the large-diameter pipe first bending portion 53d (for example, the first section 51). Therefore, the refrigerant flow rate is reduced, and “unsteady refrigerant passing sound” generated in the large-diameter pipe first curved portion 53d is prevented.

（４−２）
空調機１００の冷媒回路内を流通する冷媒が単一冷媒である。単一冷媒では沸点が一箇所しかなく冷媒状態が液相から二相に一気に変わるので、湾曲部における「非定常な冷媒通過音」の発生が顕著になると推測されるが、空調機１００では、大径管第１湾曲部５３ｄの流路面積が大径管第１湾曲部５３ｄより電動膨張弁１４側に在る部分（例えば、第１区間５１）の流路断面積よりも大きいので、単一冷媒を使用しても大径管第１湾曲部５３ｄにおける「非定常な冷媒通過音」の発生が防止される。その結果、Ｒ３２の単一冷媒を使用することが可能となり、Ｒ３２は圧損が低いので配管全体として細径化が促進される。 (4-2)
The refrigerant circulating in the refrigerant circuit of the air conditioner 100 is a single refrigerant. With a single refrigerant, the boiling point has only one location, and the refrigerant state changes from a liquid phase to a two-phase at a stretch. Therefore, it is estimated that the occurrence of “unsteady refrigerant passing sound” in the curved portion becomes significant. Since the channel area of the large-diameter tube first bending portion 53d is larger than the channel cross-sectional area of the portion (for example, the first section 51) on the electric expansion valve 14 side than the large-diameter tube first bending portion 53d, Even if one refrigerant is used, generation of “unsteady refrigerant passing sound” in the first curved portion 53d of the large-diameter pipe is prevented. As a result, it becomes possible to use a single refrigerant of R32, and R32 has a low pressure loss, so that the diameter of the entire pipe is reduced.

＜第２実施形態＞
第１実施形態では、大径管第１湾曲部５３ｄの流路断面積を通常管鉛直部５３ａの流路断面積の２倍程度にすることによって、「非定常な冷媒通過音」の発生を抑制している。 Second Embodiment
In the first embodiment, the occurrence of “unsteady refrigerant passage noise” is generated by setting the flow passage cross-sectional area of the first curved portion 53d of the large-diameter pipe to about twice the flow passage cross-sectional area of the normal pipe vertical portion 53a. Suppressed.

しかし、湾曲部の流路断面積を拡大するために大径管を採用すると、曲げ加工が困難なだけでなく、仮に曲げ径を大きくすると湾曲部が周辺機器と干渉するので、曲げ径を大きくすることができない程に空間が制約されている場合もある。そこで、第２実施形態では、複数の分岐管を用いて「非定常な冷媒通過音」を解消する方法について説明する。 However, if a large-diameter pipe is used to expand the flow path cross-sectional area of the curved portion, not only is bending difficult, but if the bending diameter is increased, the bending portion interferes with peripheral devices, so the bending diameter is increased. Sometimes the space is constrained to the extent that it cannot be done. Therefore, in the second embodiment, a method for eliminating “unsteady refrigerant passing sound” using a plurality of branch pipes will be described.

第２実施形態は、第１実施形態における配管５０の第２区間５３を他の第２区間５４に置き換えた以外は、同様の構成を採用しているので、ここでは第２区間５４についてのみ説明する。 Since the second embodiment employs the same configuration except that the second section 53 of the pipe 50 in the first embodiment is replaced with another second section 54, only the second section 54 will be described here. To do.

（１）配管５０の第２区間５４の構成
図４Ｃは、本発明の第２実施形態に係る冷凍装置において、「非定常な冷媒通過音」の解消対策後の配管が接続された室内熱交換器１５の側面図である。また、図５は、図４Ｃの第１湾曲部５２ｄ周辺の斜視図である。 (1) Configuration of the second section 54 of the pipe 50 FIG. 4C shows the indoor heat exchange to which the pipe after the countermeasure for eliminating the “unsteady refrigerant passing sound” is connected in the refrigeration apparatus according to the second embodiment of the present invention. FIG. FIG. 5 is a perspective view of the periphery of the first bending portion 52d of FIG. 4C.

図４Ｃ及び図５において、第２区間５４は、図４Ａにおける第２区間５２の第１湾曲部５２ｄの流路断面積がほぼ２倍になるように管内径６．３５ｍｍの２本の分岐管５４１，５４２に置き換えられている。 4C and 5, the second section 54 includes two branch pipes having a pipe inner diameter of 6.35 mm so that the cross-sectional area of the first curved portion 52 d of the second section 52 in FIG. 4A is almost doubled. 541 and 542.

第２区間５４は、鉛直部５４ａ、第１ジョイント部５４ｂ、２つの分岐管鉛直部５４ｃ、２つの分岐管第１湾曲部５４ｄ、２つの分岐管水平部５４ｅ、２つの分岐管第２湾曲部５４ｆ、２つの分岐管傾斜部５４ｇ、第２ジョイント部５４ｈ、及び通常管傾斜部５４ｉを有している。 The second section 54 includes a vertical part 54a, a first joint part 54b, two branch pipe vertical parts 54c, two branch pipe first curved parts 54d, two branch pipe horizontal parts 54e, and two branch pipe second curved parts. 54f, two branch pipe inclined parts 54g, a second joint part 54h, and a normal pipe inclined part 54i.

（１−１）鉛直部５４ａ
鉛直部５４ａは、第１区間５１と同じ管内径のまま所定距離だけ鉛直下方に延びる部分である。 (1-1) Vertical portion 54a
The vertical portion 54 a is a portion that extends vertically downward by a predetermined distance while maintaining the same tube inner diameter as the first section 51.

（１−２）第１ジョイント部５４ｂ
第１ジョイント部５４ｂは、鉛直部５４ａと２本の分岐管５４１，５４２を接続する部分である。 (1-2) First joint portion 54b
The first joint portion 54b is a portion connecting the vertical portion 54a and the two branch pipes 541 and 542.

（１−３）分岐管鉛直部５４ｃ
分岐管鉛直部５４ｃは、２本の分岐管５４１，５４２それぞれに設けられ、第１ジョイント部５４ｂから鉛直下方に所定距離だけ延びる部分である。 (1-3) Branch pipe vertical portion 54c
The branch pipe vertical portion 54c is a portion that is provided in each of the two branch pipes 541 and 542 and extends vertically downward from the first joint portion 54b by a predetermined distance.

（１−４）分岐管第１湾曲部５４ｄ
分岐管第１湾曲部５４ｄは、２本の分岐管５４１，５４２それぞれに設けられ、分岐管鉛直部５４ｃを所定曲率で水平方向に方向転換する部分である。なお、湾曲部の曲げ半径は３０ｍｍ以下であり、２０ｍｍが望ましい。 (1-4) Branch pipe first curved portion 54d
The branch pipe first bending portion 54d is a portion that is provided in each of the two branch pipes 541 and 542 and changes the direction of the branch pipe vertical portion 54c in the horizontal direction with a predetermined curvature. The bending radius of the curved portion is 30 mm or less, and preferably 20 mm.

（１−５）分岐管水平部５４ｅ
分岐管水平部５４ｅは、２本の分岐管５４１，５４２それぞれに設けられ、分岐管第１湾曲部５４ｄの終端から所定距離だけ水平に延びる部分である。 (1-5) Branch pipe horizontal portion 54e
The branch pipe horizontal portion 54e is a portion that is provided in each of the two branch pipes 541 and 542 and extends horizontally by a predetermined distance from the end of the branch pipe first curved portion 54d.

（１−６）分岐管第２湾曲部５４ｆ
分岐管第２湾曲部５４ｆは、２本の分岐管５４１，５４２それぞれに設けられ、分岐管水平部５４ｅの終端から所定曲率で斜め下方に方向転換する部分である。 (1-6) Branch pipe second bending portion 54f
The branch pipe second bending portion 54f is a portion that is provided in each of the two branch pipes 541 and 542, and changes direction obliquely downward with a predetermined curvature from the end of the branch pipe horizontal portion 54e.

（１−７）分岐管傾斜部５４ｇ
分岐管傾斜部５４ｇは、２本の分岐管５４１，５４２それぞれに設けられ、分岐管第２湾曲部５４ｆの終端から所定距離だけ斜め下方に延びる部分である。 (1-7) Branch pipe inclined part 54g
The branch pipe inclined portion 54g is a portion that is provided in each of the two branch pipes 541 and 542 and extends obliquely downward by a predetermined distance from the end of the branch pipe second curved portion 54f.

（１−８）第２ジョイント部５４ｈ
第２ジョイント部５４ｈは、２本の分岐管５４１，５４２それぞれの分岐管傾斜部５４ｇの終端をまとめて通常管傾斜部５３１ｉに繋ぐ部分である。 (1-8) Second joint portion 54h
The second joint part 54h is a part that collectively connects the terminal ends of the branch pipe inclined parts 54g of the two branch pipes 541 and 542 to the normal pipe inclined part 531i.

（１−９）通常管傾斜部５４ｉ
通常管傾斜部５４ｉは、内径が第１区間５１の内径と同じで、第２ジョイント部５４ｈと室内熱交換器１５の冷媒入口１５ａを結ぶ部分である。 (1-9) Normal pipe inclined part 54i
The normal pipe inclined portion 54 i has the same inner diameter as that of the first section 51 and is a portion connecting the second joint portion 54 h and the refrigerant inlet 15 a of the indoor heat exchanger 15.

（２）作用と効果
鉛直部５４ａを流れる冷媒を２本の分岐管５４１，５４２に分流させることは、実質的に管径を拡大したことと同等である。また、管径の大きい１本の管を曲げ加工するよりも、複数の小径管それぞれに湾曲部を成形した方が加工性もよく、さらに湾曲部の占有空間を縮小できるというメリットがある。 (2) Action and Effect Dividing the refrigerant flowing through the vertical portion 54a into the two branch pipes 541 and 542 is substantially equivalent to expanding the pipe diameter. Rather than bending a single pipe having a large pipe diameter, forming the curved portion on each of the plurality of small-diameter pipes has better workability and further has the advantage that the space occupied by the curved portion can be reduced.

（３）特徴
空調機１００では、電動膨張弁１４と室内熱交換器１５とを結ぶ配管５０が、室内ユニット２内で１本の管から２本の分岐管５４１，５４２に分岐されている。分岐管第１湾曲部５４ｄは、２本の分岐管５４１，５４２それぞれに設けられている。その結果、流路断面積の総和は分岐管５４１，５４２手前の流路断面積よりも大きくなり、分岐管５４１，５４２の径は手前の管径よりも小さくすることができるので曲げ加工が容易になる。 (3) Features In the air conditioner 100, the pipe 50 connecting the electric expansion valve 14 and the indoor heat exchanger 15 is branched from one pipe into two branch pipes 541 and 542 in the indoor unit 2. The branch pipe first curved portion 54d is provided in each of the two branch pipes 541 and 542. As a result, the sum of the cross-sectional areas of the flow paths is larger than the cross-sectional area of the flow paths before the branch pipes 541 and 542, and the diameter of the branch pipes 541 and 542 can be made smaller than the diameter of the front pipe, so that bending is easy. become.

（４）その他
図４Ｃ及び図５で示した実施形態では、２本の分岐管５４１，５４２を流れる冷媒が室内熱交換器１５に入る前に合流するように、２本の分岐管５４１，５４２が一本の通常管傾斜部５４ｉに接続されている。 (4) Others In the embodiment shown in FIGS. 4C and 5, the two branch pipes 541 and 542 are so arranged that the refrigerant flowing through the two branch pipes 541 and 542 merges before entering the indoor heat exchanger 15. Is connected to one normal pipe inclined portion 54i.

しかし、これに限定されるものではなく、２本の分岐管５４１，５４２を流れる冷媒を合流させずにそのまま室内熱交換器１５に入れてもよい。 However, the present invention is not limited to this, and the refrigerant flowing through the two branch pipes 541 and 542 may be directly put into the indoor heat exchanger 15 without being merged.

但し、再熱ドライなどを行うタイプでは、冷媒は合流させて室内熱交換器１５に入れた方がよい。 However, in the type in which reheat drying or the like is performed, it is preferable that the refrigerants are merged and put into the indoor heat exchanger 15.

本願発明は、床置タイプの室内ユニットを例にして説明されているが、これに限らず壁掛タイプの室内ユニットにも有用である。 Although the present invention has been described by taking a floor-standing type indoor unit as an example, the present invention is not limited to this and is also useful for a wall-hanging type indoor unit.

１１圧縮機
１３室外熱交換器（凝縮機）
１４電動膨張弁（膨張機構）
１５室内熱交換器（蒸発器）
５０電動膨張弁と室内熱交換器とを結ぶ配管
５３ｄ大径管第１湾曲部（湾曲部）
５４ｄ分岐管第１湾曲部（湾曲部）
５４１分岐管
５４２分岐管
１００空調機（冷凍装置） 11 Compressor 13 Outdoor heat exchanger (condenser)
14 Electric expansion valve (expansion mechanism)
15 Indoor heat exchanger (evaporator)
50 Piping 53d connecting the electric expansion valve and the indoor heat exchanger The first curved portion (curved portion) of the large-diameter tube
54d 1st bending part of a branch pipe (bending part)
541 Branch pipe 542 Branch pipe 100 Air conditioner (refrigeration equipment)

特開２００８−２５６２７６公報JP 2008-256276 A

Claims

At least the evaporator (15) of the refrigerant circuit in which the compressor (11), the condenser (13), the expansion mechanism (14), and the evaporator (15) are connected in order is disposed in the indoor unit (2), A refrigeration apparatus for cooling by the evaporator (15),
A pipe (50) connecting the expansion mechanism (14) and the evaporator (15) has a curved portion (53d, 54d) arranged in the indoor unit (2),
The flow passage area of the curved portion (53d, 54d) is larger than the flow passage cross-sectional area of the portion of the pipe (50) that is closer to the expansion mechanism (14) than the curved portion (53d, 54d).
Refrigeration equipment.

The pipe (50) connecting the expansion mechanism (14) and the evaporator (15) is branched from one pipe into two branch pipes (541, 542) in the indoor unit (2). And
The curved portion (54d) is provided in each of the two branch pipes (541, 542).
The refrigeration apparatus according to claim 1.

The two branch pipes (541, 542) are connected to one pipe so that the refrigerant flowing through the two branch pipes (541, 542) merges before entering the evaporator (15). Yes,
The refrigeration apparatus according to claim 2.

The refrigerant circulating in the refrigerant circuit is a single refrigerant,
The refrigeration apparatus according to any one of claims 1 to 3.

The refrigerant circulating in the refrigerant circuit is a single refrigerant of R32.
The refrigeration apparatus according to any one of claims 1 to 3.

The bending radius of the curved portion (53d, 54d) is 30 mm or less.
The refrigeration apparatus according to any one of claims 1 to 5.