ES2941545T3 - Indoor heat exchanger and air conditioning device - Google Patents

Abstract

Provided are: an indoor heat exchanger having a plurality of flat tubes configured so that dispersion of condensed water can be suppressed; and an air conditioning device. An indoor heat exchanger (51) is used for an indoor unit (3) for an air conditioning device (1) and is provided with a plurality of indoor flat tubes (55) having refrigerant flow passages (55c) and they are arranged one above each other. other; and a plurality of inner fins (60) attached to the plurality of inner flat tubes (55). The inner fins (60) have a vertically extending inner communication section (64) connected to portions located between the inner flat tubes (55) arranged one above the other, and satisfy the ratio of 4.0 <= DP/HT <= 10.0 (where HT is the height of an inner flat tube (55), and DP is the pitch of the inner flat tubes (55) arranged one above the other). (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

Indoor heat exchanger and air conditioning device

technical field

The present disclosure relates to an air conditioning apparatus as defined in the preamble of claim 1, and as illustrated in JP 2010 054060.

Background art

As an existing outdoor heat exchanger included in an outdoor unit of an air conditioning apparatus, for example, JP 2016 041986 A discloses an outdoor heat exchanger in which heat transfer fins are attached to a plurality of flat tubes.

JP 2002 139282 A discloses a heat exchanger, in which a multitude of sheet-type fins are arranged in parallel, and from the airflow upstream side, sheet-type heat transfer tubes are inserted. flat into slotted holes to braze tube to fin.

JP 2010 054 060 A discloses an auxiliary heat exchanger having a circular heat transfer tube, and a main heat exchanger being equipped with multilayered tabular fins parallel to each other and having openings for allowing airflow between them, the flat tube inserted perpendicularly into the tabular fins, and louvers arranged in a plurality of rows on the fins with respect to an airflow.

Compendium of the invention

technical problem

When, in an indoor unit of an air conditioning apparatus, such a heat exchanger in which heat transfer fins are attached to a plurality of flat tubes is used, a problem occurs that condensation water from Dew that is generated when the heat exchanger functions as an evaporator for the refrigerant is dispersed into an indoor space.

The present disclosure has been made considering the above-described situation, and one of the objects of the present disclosure is to provide an air conditioning apparatus comprising an indoor heat exchanger including a plurality of flat tubes capable of suppressing water dispersion. dew condensation, and an air conditioning apparatus.

Solution to the problem

The invention is defined in independent claim 1. Preferred embodiments thereof are specified in the dependent claims.

An air conditioning apparatus according to a first aspect comprises an indoor heat exchanger used in an indoor unit and an outdoor heat exchanger used in an outdoor unit. The indoor heat exchanger includes a plurality of flat tubes and a plurality of heat transfer fins. Each of the flat tubes includes a flow channel that allows coolant to pass through an interior portion thereof. The plurality of flat tubes are vertically juxtaposed. The plurality of heat transfer fins are attached to the plurality of flat tubes. Each of the heat transfer fins includes a continuous part. The continuous part extends vertically. The continuous part of each heat transfer fin is a heat transfer fin part and is continuous with parts positioned between the vertically juxtaposed flat tubes.

The outdoor heat exchanger includes a plurality of flat tubes that are vertically juxtaposed and each includes a flow channel that allows coolant to pass through an interior portion thereof, and a plurality of heat transfer fins attached to the plurality of flat tubes, wherein each of the heat transfer fins includes a vertically extending continuous portion that is continuous with portions positioned between the vertically juxtaposed flat tubes.

The DP/HT value of the indoor heat exchanger is less than the DP/HT value of the outdoor heat exchanger. HT represents the height of each of the flat tubes. DP represents the pitch of the vertically juxtaposed flat tubes.

The indoor heat exchanger enables suppression of dew condensation water scattering that is generated when the indoor heat exchanger is used as an evaporator for refrigerant while suppressing the formation of frost that occurs when the outdoor heat exchanger is used as an evaporator for refrigerant.

An air conditioning apparatus according to a second aspect is the air conditioning apparatus according to the first aspect, wherein the flat tubes of the indoor heat exchanger each include a plurality of air-side flat tubes. upstream side arranged on the upstream side in the air flow direction, and a plurality of downstream side flat tubes arranged on the downstream side in the air flow direction with respect to the side flat tubes. upstream.

The indoor heat exchanger makes it possible to suppress the scattering of dew condensation water from the downstream-side ends of the downstream-side flat tubes in the airflow direction. An air conditioning apparatus according to a third aspect is the air conditioning apparatus according to either the first aspect or the second aspect, wherein the continuous part of the indoor heat exchanger is positioned on the leeward side of the flat tubes in the airflow direction.

The indoor heat exchanger enables the suppression of the scattering of dew condensation from the downstream side ends of the heat transfer fins in the direction of airflow by guiding the dew condensation that has generated in the flat tubes so that it travels down along the continuous parts of the heat transfer fins positioned on the downstream side in the direction of the air flow.

An air conditioning apparatus according to a fourth aspect is the air conditioning apparatus according to any one of the first aspect to the third aspect, wherein the heat transfer fins of the indoor heat exchanger each include a cut part and elevated. The longitudinal direction of the cut and raised part is the direction from top to bottom.

Since each of the heat transfer fins includes the cut and raised part, the inner heat exchanger enables an improvement in the heat transfer performance.

An air conditioning apparatus according to a fifth aspect is the air conditioning apparatus according to any one of the first aspect to the fourth aspect, in which the ratio of 4.6 < DP/HT < 8.0 of the indoor heat exchanger is fulfilled.

The indoor heat exchanger more easily suppresses the scattering of dew condensation water that is generated when the indoor heat exchanger is used as a refrigerant evaporator.

Brief description of the drawings

[fig. 1] Fig. 1 is a schematic diagram of an air conditioning apparatus.

[fig. 2] Fig. 2 is a perspective view schematically illustrating the external appearance of an outdoor unit.

[fig. 3] Fig. 3 is a schematic plan view of an outdoor unit.

[fig. 4] Fig. 4 is a perspective view schematically illustrating the external appearance of an outdoor heat exchanger.

[fig. 5] Fig. 5 is an illustration of a positional relationship between outer fins and outer flat tubes. [fig. 6] Fig. 6 is a perspective view schematically illustrating the external appearance of an indoor unit.

[fig. 7] Fig. 7 is a schematic plan view of an indoor unit.

[fig. 8] Fig. 8 is a schematic side view of the indoor unit according to section A-A of Fig. 7.

[fig. 9] Fig. 9 is a perspective view schematically illustrating the external appearance of an indoor heat exchanger.

[fig. 10] Fig. 10 is a partially enlarged perspective view schematically illustrating the external appearance of the indoor heat exchanger.

[fig. 11] Fig. 11 is an illustration of the positional relationship between inner fins and inner flat tubes.

[fig. 12] Fig. 12 is an illustration of a joined state between the inner fins and the inner flat tubes. [fig. 13] Fig. 13 is an illustration of the positional relationship between inner fins and inner flat tubes according to a modification A.

[fig. 14] Fig. 14 is an illustration of a part of a water guide rib included in each of the inner fins according to modification A, according to section BB of Fig. 13, said part being in the vicinity from the downstream side in an airflow direction.

Description of embodiments

(1) Configuration of the air conditioning apparatus

Fig. 1 is a schematic diagram of an air conditioning apparatus 1.

The air conditioning apparatus 1 is an apparatus capable of cooling and heating a room in a building or the like by performing a vapor compression refrigeration cycle.

The air conditioning apparatus 1 mainly includes an outdoor unit 2, an indoor unit 3, and a liquid refrigerant connection pipe 4 and a gaseous refrigerant connection pipe 5 which are refrigerant paths connecting the unit with each other. outdoor 2 and indoor unit 3. A vapor compression refrigerant circuit 6 of the air conditioning apparatus 1 is constituted by the outdoor unit 2 and the indoor unit 3 connected to each other through the connection pipes 4 and 5 of refrigerant. The refrigerant connection pipes 4 and 5 are refrigerant pipes that are built locally during the installation of the air conditioning apparatus 1 at an installation location in a building or the like. In the present embodiment, the refrigerant circuit 6 is filled with R32 as a working refrigerant; however, the working coolant is not limited thereto.

(2) Outdoor unit

(2-1) General configuration of outdoor unit

The outdoor unit 2 is installed outdoors (for example, on the roof of a building or close to the surface of a wall of a building) and constitutes a part of the refrigerant circuit 6. The outdoor unit 2 mainly includes an accumulator 7, a compressor 8, a four-way switching valve 10, an outdoor heat exchanger 11, an outdoor expansion valve 12 as an expansion mechanism, a side stop valve 13 of the liquid, a shut-off valve 14 on the gas side, an outdoor fan 15 and a casing 40.

The accumulator 7 is a container for supplying gaseous refrigerant to the compressor and is arranged on the suction side of the compressor 8.

The compressor 8 sucks in and compresses a low-pressure gaseous refrigerant and discharges a high-pressure gaseous refrigerant.

The outdoor heat exchanger 11 is a heat exchanger that works during a cooling operation as a radiator for the refrigerant that is discharged from the compressor 8 and that works during a heating operation as an evaporator for the refrigerant that is sent from an exchanger 51 of inner heat. The outdoor heat exchanger 11 is connected on the liquid side thereof to the outdoor expansion valve 12 and is connected on the gas side thereof to the four-way switching valve 10.

The outdoor expansion valve 12 is an electric expansion valve capable, during a refrigeration operation, of decompressing refrigerant whose heat is radiated in the outdoor heat exchanger 11 before sending the refrigerant to the indoor heat exchanger 51 and, during an operation of heating, of decompressing refrigerant whose heat is radiated in the indoor heat exchanger 51 before sending the refrigerant to the outdoor heat exchanger 11.

One end of the liquid refrigerant connection pipe 4 is connected to the liquid side stop valve 13 of the outdoor unit 2. One end of the gas refrigerant connection pipe 5 is connected to the liquid side stop valve 14 of the outdoor unit 2. gas from outdoor unit 2.

The devices of the outdoor unit 2 and the valves are connected to each other by refrigerant pipes 16 to 22.

The four-way switching valve 10 switches between a connection state for a cooling operation and a connection state for a heating operation, which will be described later, switching between a state (see solid lines in the four-way switching valve 10 four-way switch of Fig. 1) in which the discharge side of the compressor 8 is connected to the outdoor heat exchanger 11 side and in which the suction side of the compressor 8 is connected to the intake valve 14 side. gas-side shut-off and a state (see the broken lines in the four-way switching valve 10 in Fig. 1) in which the discharge side of the compressor 8 is connected to the gas-side shut-off valve 14 side. of the gas and in which the suction side of the compressor 8 is connected to the side of the outdoor heat exchanger 11.

The outdoor fan 15 is arranged in an indoor part of the outdoor unit 2, and after taking in outdoor air and supplying the outdoor air to the outdoor heat exchanger 11, it forms an air flow (indicated by arrows in Fig. 3) which is discharged outside the unit. As before, the outdoor air supplied by the outdoor fan 15 is used as a cooling source or a heating source in a heat exchange with the refrigerant of the outdoor heat exchanger 11.

As illustrated in the perspective view schematically illustrating the external appearance of the outdoor unit 2 in Fig. 2 and in the schematic plan view of the outdoor unit 2 in Fig. 3, the casing 40 mainly includes a lower frame 40a, a top panel 40b, a left front panel 40c, a right front panel 40d and a right side panel 40e. The lower frame 40a is a laterally elongated substantially rectangular plate-shaped element constituting the bottom surface portion of the housing 40. The lower frame 40a is attached to a local mounting surface via fixed feet 41 fixed to the surface. bottom of lower frame 40a. The top panel 40b is a laterally elongated substantially rectangular plate-shaped element constituting the upper surface part of the casing 40. The left front panel 40c is a plate-shaped element constituting mainly the surface part left front and the left side surface part of the casing 40 and includes two exhaust ports for expelling, to the front surface side, the air that has entered the casing 40 from the rear surface side and the left side. from the left side surface by means of the external fan 15. The exhaust ports are vertically juxtaposed. A fan grill 42 is provided at each of the exhaust ports. The right front panel 40d is a plate-shaped element that mainly constitutes the right front surface part and the right side surface front part of the casing 40. The right side panel 40e is a plate-shaped element which mainly constitutes the rear part of the right side surface and the part of the right rear surface of the casing 40.

In the casing 40, a partition plate 43 is arranged which divides from each other a fan room in which the outdoor fan 15 and the like are arranged and a machine room in which the compressor 8 and the like are arranged.

(2-2) General structure of outdoor heat exchanger

Fig. 4 is a perspective view schematically illustrating the external appearance of the outdoor heat exchanger 11.

The outdoor heat exchanger 11 mainly includes a gas side flow divider 23, a liquid side flow divider 24, a plurality of inlet flow side return elements 25, a plurality of inlet flow side 26 elements, non-inlet flow side return, a plurality of outer flat tubes 90 and a plurality of outer fins 91. All of these components constituting the outdoor heat exchanger 11 are made of aluminum or an aluminum alloy and joined together by welding strong or similar.

The plurality of outer flat tubes 90 are vertically juxtaposed.

The plurality of outer fins 91 are arranged side by side in the thickness direction of the plate thereof to extend along the outer flat tubes 90 and are attached to the plurality of outer flat tubes 90.

The gas side flow divider 23 is connected to the refrigerant pipe 19 and, of the plurality of the outer flat tubes 90, to the outer flat tubes 90 arranged at a top. When the outdoor heat exchanger 11 functions as a radiator for the refrigerant, the flow of the refrigerant which has flowed from the refrigerant pipe 19 to the outdoor heat exchanger 11 is divided into flows at a plurality of height positions and is sent, accordingly the plurality of outer flat tubes 90, to the outer flat tubes 90 arranged at the top.

The liquid side flow divider 24 is connected to the refrigerant pipe 20 and, of the plurality of outer flat pipes 90, to outer flat pipes 90 arranged at a bottom. When the outdoor heat exchanger 11 functions as a radiator for the refrigerant, the flows of the refrigerant which have flowed out of the plurality of outer flat tubes 90 from the lower outer flat tubes 90 are merged and caused to flow. to the outside of the outdoor heat exchanger 11 through the refrigerant pipe 20.

The plurality of inlet flow-side return elements 25 are arranged between the gas-side flow divider 23 and the liquid-side flow divider 24 and connect ends of the outer flat tubes 90 arranged at height positions with respect to each other. Different from each other.

The inflow-opposite-side return elements 26 are arranged at one end of the outdoor heat exchanger 11 on an opposite side to the side where the gas-side flow divider 23, the gas-side flow divider 24, and the liquid and the plurality of return elements 25 on the inflow side. The non-inflow side return elements 26 connect ends of the outer flat tubes 90 arranged at mutually different height positions from each other.

As before, by including the plurality of inflow side return elements 25 and non-inflow side return elements 26, the outdoor heat exchanger 11 enables the refrigerant to flow while turning in both ends of the outdoor heat exchanger 11.

(2-3) Outer flat tube

Fig. 5 illustrates a positional relationship between the outer fins 91 and the outer flat tubes 90 seen, sectioned according to a section perpendicular to a direction in which the flow channels 90c extend in inner parts of the outer flat tubes 90, in the direction in which the flow channels 90c extend.

Each of the outer flat tubes 90 includes a vertically upwardly facing upper side flat surface 90a constituting the upper surface, a vertically downward facing lower side flat surface 90b constituting the lower surface, and a large number of flow channels 90c that are small and in which the coolant flows. The plurality of flow channels 90c included in the outer flat tubes 90 are arranged side by side in the direction of air flow (indicated by arrows in Fig. 5; the longitudinal direction of the outer flat tubes 90 in one view in section of the flow channels 90c). The plurality of outer flat tubes 90 that are used are identical to each other in terms of a height HT in a top-down direction. The height HT indicates a width between the upper side flat surface 90a and the lower side flat surface 90b of each outer flat tube 90 in the height direction. The plurality of outer flat tubes 90 are arranged in the up-down direction with a predetermined pitch (pitch DP). The pitch DP is an interval between the flat surfaces 90a on the upper side of the outer flat tubes 90.

The outdoor heat exchanger 11 of the present embodiment is configured so that the downstream side ends of the plurality of flat outdoor tubes 90 in the airflow direction are positioned on the downstream side of the downstream side ends. downstream of the outer fins 91 in the direction of the air flow. Accordingly, the leeward side ends of the outer fins 91 are prevented from being damaged or broken during the manufacture or transportation of the outdoor heat exchanger 11.

(2-4) Outer fin

The outer fins 91 are plate-shaped elements that extend in the direction of the air flow and in the direction from top to bottom. A plurality of outer fins 91 are arranged in the thickness direction of the plate thereof at predetermined intervals and attached to the outer flat tubes 90.

Each of the outer flaps 91 includes a plurality of insert parts 92, an outer continuous part 97a, a plurality of leeward parts 97b, an embossed part 93, windward side flap tabs 94a, windward side flap tabs 94b leeward side, outer slits 95, windward side ribs 96a, leeward side ribs 96b and the like. The thickness of each outer fin 91 at a flat part in the direction of the thickness of the plate is, for example, 0.05 mm or more and 0.15 mm or less.

Each of the insert portions 92 is formed by cutting horizontally from the leeward side edge of the outer flap 91 toward the windward side to a portion before the windward side edge thereof. The plurality of insert parts 92 are arranged next to each other in the top-down direction. The insert parts 92 constitute a fin collar that is formed by flashing or the like. The shape of each of the insert parts 92 substantially coincides with the outer shape of the section of each outer flat tube 90. The outer flat tubes 90 are fixed to the outer fins 91 by the insert parts 92 by brazing in a insertion state in the insertion parts 92.

The outer continuous part 97a is, of each outer fin 91, a part that is continuous in the up and down direction on the most windward side from the windward side ends of the outer flat tubes 90. From the point of view of For frost-proof performance, the distance in the airflow direction from the windward ends of the outer flat tubes 90 to the windward end of the outer continuous part 97a of each outer fin 91 is preferably 4 mm or more.

The plurality of leeward portions 97b extend from different height positions on the outer continuous part 97a to the downstream side in the airflow direction. Each leeward part 97b is surrounded in the top-down direction by the insert parts 92 adjacent to each other.

The embossed part 93 is formed, on each outer fin 91, in the vicinity of the center in the direction of the air flow and is configured to include a part with protrusions and a part without protrusions in the direction of the thickness of the plate.

The windward side flap tabs 94a and the leeward side flap tabs 94b are disposed in the vicinity of the windward side ends and in the vicinity of the leeward side ends, respectively, to restrict the interval between the outer fins 91.

Each outer slit 95 is a part that is shaped by being cut and raised in the thickness direction of the plate from a flat part to improve the heat transfer performance of the outer fins 91 and is formed on the downstream side of the embossed part 93 in the direction of the air flow. Each outer slot 95 has a longitudinal direction in the up-down direction (the lay-out direction of the outer flat tubes 90). A plurality (two in the present embodiment) of the outer slits 95 are arranged side by side in the direction of the air flow. These outer slits 95 are cut and raised from the top flat on the same side in the direction of the thickness of the plate, thus having openings on the upstream side and downstream side in the airflow direction, respectively.

The windward side ribs 96a are arranged above and below the windward side flap tabs 94a to extend in the airflow direction between mutually adjacent outer flat tubes 90 in the vertical direction. The leeward side ribs 96b continue from the leeward side ends of the windward side ribs 96a and extend further to the leeward side.

(3) Indoor unit

(3-1) General configuration of the indoor unit

Fig. 6 is a perspective view of the external appearance of the indoor unit 3. Fig. 7 is a schematic plan view of the indoor unit 3 with its upper panel removed. Fig. 8 is a schematic side sectional view of the indoor unit 3 according to a section indicated by A-A in Fig. 7.

In the present embodiment, the indoor unit 3 is an indoor unit of a type that is installed on the ceiling of a room or the like that is an air-conditioning object space by embedding it in a ceiling opening. The indoor unit 3 constitutes a part of the refrigerant circuit 6. The indoor unit 3 mainly includes the indoor heat exchanger 51, an indoor fan 52, a casing 30, a door 39, a bell mouth 33 and a drain pan 32.

The indoor heat exchanger 51 is a heat exchanger that works, during a cooling operation, as an evaporator for the refrigerant sent from the indoor heat exchanger 51 and works, during a heating operation, as a radiator for the refrigerant discharged from the compressor. 8. The indoor heat exchanger 51 is connected on the liquid side thereof to the indoor side end of the liquid refrigerant connection pipe 4 and is connected on the gas side thereof to the indoor side end of the pipe 5 gas refrigerant connection.

The indoor fan 52 is a centrifugal fan arranged in an inner part of a casing body 31 of the indoor unit 3. The indoor fan 52 draws indoor air through an intake port 36 of a decoration panel 35 into the casing 30 and , after making the air pass through the indoor heat exchanger 51, forms an air flow (indicated by arrows in Fig. 8) which is exhausted outside the casing 30 through an exhaust port 37 of the decorative panel 35. The indoor air thus supplied by the indoor fan 52 exchanges heat with the refrigerant in the indoor heat exchanger 51, and thus the temperature of the indoor air is controlled.

The casing 30 mainly includes the casing body 31 and the decoration panel 35.

The casing body 31 is arranged to be inserted into an opening formed in a U-ceiling of an air-conditioned room. In plan view, the casing body 31 is a substantially octagonal box-shaped body having long sides and short sides alternately formed. The casing body 31 has an open bottom surface. The casing body 31 includes a top panel and a plurality of side plates that extend downward from the peripheral part of the top panel.

The decorative panel 35 is arranged to fit into the roof opening U and extends further on the outer side in plan view than the top panel and the side plates of the casing body 31. The decoration panel 35 is mounted below the casing body 31 from the inner side. The decorative panel 35 includes an inner frame 35a and an outer frame 35b. On the inner side of the inner shell 35a, the downwardly opening intake port 36 is formed and has a substantially quadrangular shape. A filter 34 for removing dust from the air that has been sucked in through the intake port 36 is arranged above the intake port 36. In an area which is on the inner side of the outer shell 35b and on the outer side of the inner shell 35a, the exhaust port 37 and a corner exhaust port 38 are formed which open obliquely downward from the upper part. bottom of that area. The exhaust port 37 includes, at locations corresponding to the sides of the substantially quadrangular shape of the decorative panel 35 in plan view, a first exhaust port 37a, a second exhaust port 37b, a third exhaust port 37c and a fourth exhaust port 37d. The corner exhaust port 38 includes, at locations corresponding to the four corners of the substantially quadrangular shape of the decorative panel 35 in plan view, a first corner exhaust port 38a, a second corner exhaust port 38b, a third corner exhaust port 38c, corner exhaust and a fourth port 38d corner exhaust.

The gate 39 is an element capable of changing the direction of an air flow passing through the exhaust port 37. The gate 39 includes a first gate 39a arranged at the first exhaust port 37a, a second gate 39b arranged at the second exhaust port 37b, a third gate 39c arranged at the third exhaust port 37c and a fourth gate 39d arranged at the third exhaust port 37c. fourth exhaust port 37d. Each of the gates 39a through 39d is rotatably supported at a predetermined location on the casing 30.

The drain pan 32 is arranged on the lower side of the indoor heat exchanger 51 and receives drainage water that is generated as a result of moisture in the air condensing on the indoor heat exchanger 51. The drain pan 32 is mounted to a lower part of the casing body 31. Tray 32 of The drain includes a cylindrical space extending in the up-down direction on the inner side of the indoor heat exchanger 51 in plan view. The flared mouth 33 is arranged in an inner lower part of the space. The flared mouth 33 guides the air that is taken in through the intake port 36 to the indoor fan 52. The drain pan 32 includes a plurality of exhaust flow channels 47a to 47d and corner exhaust flow channels 48a to 48c that they extend in the top-down direction on the outside of the indoor heat exchanger 51 in plan view. The exhaust flow channels 47a to 47d include a first exhaust flow channel 47a in communication at the lower end thereof with the first exhaust port 37a, a second exhaust flow channel 47b in communication at the lower end thereof with the second exhaust port 37b, a third exhaust flow channel 47c in communication at the lower end thereof with the third exhaust port 37c and a fourth exhaust flow channel 47d in communication at the lower end thereof with the fourth exhaust port 37d. The corner exhaust flow channels 48a to 48c include a first corner exhaust flow channel 48a in communication at the lower end thereof with the first corner exhaust port 38a, a second corner exhaust flow channel 48b in communication at the lower end thereof with the second corner exhaust port 38b and a third corner exhaust flow channel 48c in communication at the lower end thereof with the third corner exhaust port 38c.

(3-2) General structure of indoor heat exchanger

Fig. 9 is a perspective view schematically illustrating the external appearance of the indoor heat exchanger 51. Fig. 10 is a partially enlarged perspective view of the external appearance of the inner heat exchanger 51 on the windward side of a plurality of inner fins 60.

The indoor heat exchanger 51 is arranged, in an inner part of the casing body 31, at a height position identical to the height position of the indoor fan 52 in a bending state to surround the periphery of the indoor fan 52. The exchanger The inner heat 51 mainly includes a liquid-side header 81, a gas-side header 71, a return header 59, a plurality of inner flat tubes 55 and a plurality of inner fins 60. All of these components constituting the indoor heat exchanger 51 are formed from aluminum or an aluminum alloy and are joined together by brazing or the like.

The indoor heat exchanger 51 includes a windward heat exchange section 70 (inner part in plan view) constituting the windward side thereof in the airflow direction, and a leeward heat exchange section 80 (external part in plan view) that constitutes the leeward side thereof. In the direction of the air flow.

The liquid side header 81 of the indoor heat exchanger 51 constitutes an end of the leeward heat exchange section 80 in plan view and is a cylindrical member extending in the top-down direction. An inner side end of the liquid refrigerant connection pipe 4 is connected to the liquid side header 81. A plurality of the inner flat tubes 55 of the inner heat exchanger 51 constituting the leeward heat exchange section 80 are connected to the liquid side header 81 to be arranged side by side vertically.

The gas side header 71 of the indoor heat exchanger 51 constitutes an end of the windward heat exchange section 70 in plan view and is a cylindrical member extending in the top-down direction. The inner side end of the gaseous refrigerant connection pipe 5 is connected to the header 71 on the gas side. A plurality of the inner flat tubes 55, of the inner heat exchanger 51, constituting the windward heat exchange section 70 are connected to the gas side header 71 to be arranged side by side vertically.

The return header 59 of the indoor heat exchanger 51 constitutes an end on a side opposite to the side where the liquid-side header 81 and the gas-side header 71 are arranged in plan view and includes a plurality of return spaces arranged side by side in an inner part thereof in the top-down direction. The inner flat tubes 55 constituting the windward heat exchange section 70 and the inner flat tubes 55 constituting the leeward heat exchange section 80 are connected to return spaces arranged at height positions identical to height positions of the inner flat tubes 55. Accordingly, the return header 59, while preventing the refrigerants that have flowed through the inner flat tubes 55 at different height positions from mixing, enables the refrigerants that have flowed through the inner flat tubes 55 at respective height positions back to be sent to the inner flat tubes 55 at height positions identical to the height positions thereof on the windward side (when the indoor heat exchanger 51 operates as an evaporator for the refrigerant) or on the leeward side (when the indoor heat exchanger 51 functions as a radiator for the refrigerant). The plurality of inner flat tubes 55 include inner flat tubes constituting the windward heat exchange section 70 and inner flat tubes constituting the leeward heat exchange section 80. In other words, the plurality of inner flat tubes 55 include inner flat tubes that are juxtaposed in the up and down direction in the windward heat exchange section 70 of the indoor heat exchanger 51 and inner flat tubes that are juxtaposed in the up and down direction. from top to bottom in the leeward heat exchange section 80 of the indoor heat exchanger 51. The plurality of inner flat tubes 55 constituting the windward heat exchange section 70 are each connected by at one of their ends to the gas-side header 71 and are connected at the other end thereof to the windward side part of the return header 59. The plurality of inner flat tubes 55 constituting the leeward heat exchange section 80 are each connected at one of their ends to the header 81 on the liquid side and are connected at the other end thereof. to the leeward side portion of the return head 59.

Similarly, the plurality of inner fins 60 include inner fins constituting the windward heat exchange section 70 and inner fins constituting the leeward heat exchange section 80. In other words, the plurality of inner fins 60 include inner fins that are attached to the inner flat tubes 55 constituting the windward heat exchange section 70 of the inner heat exchanger 51, and inner fins that are attached to the flat tubes. interiors 55 constituting the leeward heat exchange section 80 of the interior heat exchanger 51. The inner fins 60 are arranged side by side in the thickness direction of the inner fin plate 60 so that each inner fin 60 extends along the inner flat tubes 55.

(3-3) Inner flat tube

Fig. 11 illustrates a positional relationship between the inner fins 60 and the inner flat tubes 55 seen in section perpendicular to a direction in which the flow channels 55c extend in the inner parts of the inner flat tubes 55, in the direction in which the flow channels 55c extend.

Each of the inner flat tubes 55 includes an upper side flat surface 55a facing vertically upwards constituting the upper surface, a lower side flat surface 55b facing vertically downward constituting the bottom surface, and a large number of of flow channels 55c which are small and in which coolant flows. The plurality of flow channels 55c included in the inner flat tubes 55 are arranged side by side in an airflow direction (indicated by arrows in Fig. 11; the longitudinal direction of the inner flat tubes 55 in one view in section of the flow channels 55c). The plurality of inner flat tubes 55 which are identical to each other in terms of the height HT in the up-down direction are used. The height HT indicates a width between the flat surface 55a on the upper side and the flat surfaces 55b on the lower side of the inner flat tubes 55 in the height direction. The height HT is preferably 1.2 mm or more and 2.5 mm or less. The plurality of inner flat tubes 55 are arranged with a predetermined pitch (interfloor pitch DP) in the up-down direction similarly in both the windward heat exchange section 70 and the leeward heat exchange section 80. . The interfloor pitch DP is an interval between the flat surfaces 55a of the upper side of the inner flat tubes 55 and is preferably 8.0 mm or more and 15.0 mm or less. The indoor heat exchanger 51 satisfies the ratio of 4.0 < DP/HT < 10.0. The lower limit of DP/HT of the indoor heat exchanger 51 is preferably 4.6 or more. The upper limit of DP/HT of the indoor heat exchanger 51 is preferably 8.0 or less. The indoor heat exchanger 51 preferably complies with the ratio of 4.6 < DP/HT < 8.0.

The air conditioning apparatus 1 of the present embodiment satisfies a relationship in which the DP/HT value of the indoor heat exchanger 51 is less than the DP/HT value of the aforementioned outdoor heat exchanger 11.

In the present embodiment, the inner flat tubes 55 constituting the windward heat exchange section 70 and the inner flat tubes 55 constituting the leeward heat exchange section 80 are arranged to overlap each other at respective height positions when They look in the direction of the airflow.

In the indoor heat exchanger 51 of the present embodiment, the upstream side ends of the plurality of inner flat tubes 55 in the airflow direction and the upstream side ends of the inner fins 60 in the airflow direction. of the airflow are arranged at substantially identical positions in the direction of the airflow.

(3-4) Inner fin

The inner fins 60 are plate-shaped elements that extend in the airflow direction and in the top-down direction. A plurality of inner fins 60 are arranged in the thickness direction of the plate thereof at predetermined intervals and attached to the inner flat tubes 55. In the present embodiment, the inner fins 60 constituting the heat exchange section 70 of windward and the inner fins 60 constituting the leeward heat exchange section 80 are arranged to substantially overlap each other when viewed in the airflow direction. The leeward side ends of the inner fins 60 constituting the windward heat exchange section 70 and the windward side ends of the inner fins 60 constituting the leeward heat exchange section 80 are arranged in contact with each other. yes at least for a part of them.

Each of the inner fins 60 constituting the windward heat exchange section 70 and each of the inner fins 60 constituting the leeward heat exchange section 80 both similarly include a main surface 61, a plurality of fin collar parts 65a, an inner continuous part 64, a plurality of windward portions 65, main grooves 62, continuous location grooves 63 and the like. The thickness of the flat main surface 61 of each of the inner fins 60 in the direction of the thickness of the plate is, for example, 0.05 mm or more and 0.15 mm or less. The pitch (the interval between mutually adjacent inner fin surfaces 60 on the same side) of the plurality of inner fins 60 in the thickness direction of the plate is preferably 1.0 mm or more and 1.6 mm or less.

The main surface 61 of the inner fins 60 constitutes a flat part in which the fin collar portions 65a, the main grooves 62 and the continuously locating grooves 63 are not arranged.

The flap collar portions 65a are formed to extend horizontally from the windward side edges of the inner flaps 60 toward the leeward side to a part before the leeward side edge. The plurality of fin collar portions 65a are arranged side by side in the top-down direction. The wing collar portions 65a are formed by flashing or the like. The contour shape of each fin collar part 65a substantially coincides with the outer sectional shape of each inner flat tube 55. The inner flat tubes 55 are attached to the inner fins 60 by the fin collar parts 65a by welding. strong in a state of insertion into the flap collar portions 65a. Fig. 12 is an illustration of a joint state between the inner fins 60 and the inner flat tubes 55 in a section of the flow channels 55c of the inner flat tubes 55 taken in the flow direction of the refrigerant along the a face that includes a vertical direction. As illustrated in Fig. 12, the fin collar portions 65a are configured by rising relative to the main surfaces 61 in the plate thickness direction of the main surfaces 61 on a side opposite to the side where they are cut and they raise the main slits 62. On a side opposite to the side of the main surfaces 61 of the fin collar parts 65a, positioning parts 65x are arranged which are bent to extend in a direction away from the flat surfaces 55a of the side (or the flat surfaces 55b on the underside) of the inner flat tubes 55 corresponding thereto. The locating parts 65x are in surface contact with the main surfaces 61 of the inner fins 60 adjacent to them, thus regulating the interval between the inner fins 60 in the direction of the thickness of the plate. As illustrated in Fig. 12, the fin collar portions 65a are brazed together with brazing materials 58 interposed between the fin collar portions 65a and the upper side flats 55a (or flats 55b). side) of the inner flat tubes 55. A distance DS between a part where the raising of the fin collar parts 65a relative to the main surfaces 61 begins and a part where the raising of the main slits 62 begins, as as illustrated in Fig. 12, on the side of the flat surfaces 55b of the bottom side of the inner flat tubes 55 is preferably 1 mm or less, but it is not limited to this. The dew condensation water on the flat surfaces 55b of the lower side of the inner flat tubes 55 is guided to move downward through the part where the elevation of the main grooves 62 begins and is drained. Therefore, setting the distance DS to a short distance of 1 mm or less makes it possible to prevent dew condensation water from continuing to remain on the flat surfaces 55b on the bottom side of the inner flat tubes 55.

The inner continuous part 64 of each inner fin 60 is a continuous part in the up and down direction on the most leeward side from the leeward side ends of the inner flat tubes 55. The ratio of a width WL of the continuous inner part 64 of each inner fin 60 in the airflow direction and a width WF of each inner fin 60 in the airflow direction preferably satisfies the ratio of 0.2 < WL/WF < 0.5.

The plurality of windward parts 65 extend from different height positions in the inner continuous part 64 towards the upstream side in the direction of the air flow. Each of the windward portions 65 is surrounded in the top-down direction by fin neck portions 65a adjacent to each other. The length of each windward part 65 in the up-down direction is defined by DP-HT.

The main grooves 62 are parts that are shaped by being cut and raised in the thickness direction of the plate from the flat main surfaces 61 to improve the heat transfer performance of the inner fins 60. The main grooves 62 are formed in the windward portions 65 of the inner flaps 60. A plurality (four in the present embodiment) of the main slits 62 are formed side by side in the airflow direction.

The continuous locating grooves 63 are also parts that are shaped by cutting and lifting them in the direction of the thickness of the plate from the flat main surfaces 61 to improve the heat transfer performance of the inner fins 60. The continuous locating grooves 63 are formed at a plurality of height positions in the inner continuous portions 64 of the inner fins 60. The continuously locating slits 63 are arranged so that each corresponds to the downstream side in the airflow direction of the the main slits 62 arranged at respective height positions. The continuous locating slits 63 are formed so that the longitudinal direction thereof is the up-down direction. Each of the continuous locating slits 63 is elongated in the up-down direction so that its upper end extends to a higher position than the upper ends of the main slits 62 corresponding thereto and such that its end bottom extends to a position lower than the lower ends of the main grooves 62 corresponding thereto.

The main grooves 62 and the continuously located grooves 63 are cut and raised from the flat main surfaces 61 on the same side in the direction of the thickness of the plate, thus having openings on the upstream side and on the downstream side. downstream in the direction of airflow, respectively.

(4) Operation of air conditioning apparatus

Next, with reference to Fig. 1, the operation of the air conditioning apparatus 1 will be described. The air conditioning apparatus 1 performs a cooling operation in which refrigerant flows through the compressor 8, the outdoor heat exchanger 11, the outdoor expansion valve 12 and the indoor heat exchanger 51 in this order and a heating operation in which the refrigerant flows through the compressor 8, the indoor heat exchanger 51, the outdoor expansion valve 12 and the outdoor heat exchanger 11 in this order.

(4-1) Cooling operation

During a cooling operation, the on state of the four-way switching valve 10 switches to make the outdoor heat exchanger 11 work as a radiator for the refrigerant and the indoor heat exchanger 51 work as an evaporator for the refrigerant (see solid lines in Fig. 1). In the refrigerant circuit 6, the compressor 8 sucks in a gaseous refrigerant at a low pressure of the refrigeration cycle, and it is discharged after compressing it at a high pressure of the refrigeration cycle. The high-pressure gaseous refrigerant discharged from the compressor 8 is sent to the outdoor heat exchanger 11 through the four-way switching valve 10. The high-pressure gaseous refrigerant sent to the outdoor heat exchanger 11 radiates heat by exchanging the heat, in the outdoor heat exchanger 11 functioning as a radiator for the refrigerant, with outdoor air supplied as a cooling source by the outdoor fan 15, thus becoming in a high pressure liquid refrigerant. The high-pressure liquid refrigerant is decompressed to a low pressure of the refrigeration cycle when it passes through the outdoor expansion valve 12, thus becoming refrigerant in a two-phase gas-liquid state. The refrigerant in a two-phase gas-liquid state is sent to the indoor unit 3 through the liquid side stop valve 13 and the liquid refrigerant connection pipe 4 .

The low-pressure refrigerant in the gas-liquid two-phase state is evaporated, in the indoor heat exchanger 51, exchanging heat with indoor air supplied as a heating source by the indoor fan 52 during a cooling operation. Consequently, the air passing through the indoor heat exchanger 51 is cooled, and cooling of the interior of a room is performed. In this case, the moisture contained in the air passing through the indoor heat exchanger 51 condenses and thus generates dew condensation water on the surface of the indoor heat exchanger 51. The low-pressure gaseous refrigerant which has evaporated in the indoor heat exchanger 51 is sent to the outdoor unit 2 through the gaseous refrigerant connection pipe 5.

The low-pressure gaseous refrigerant sent to the outdoor unit 2 is again sucked by the compressor 8 through the gas-side stop valve 14, the four-way switching valve 10 and an accumulator 7. During a cooling operation , the refrigerant circulates in the refrigerant circuit 6 as described above.

(4-2) Heating operation

During a heating operation, the on state of the four-way switching valve 10 switches to make the outdoor heat exchanger 11 work as an evaporator for the refrigerant and the indoor heat exchanger 51 work as a radiator for the refrigerant (see dashed lines in Fig. 1). In the refrigerant circuit 6, the compressor 8 sucks in a gaseous refrigerant at a low pressure of the refrigeration cycle, and it is discharged after compressing it at a high pressure of the refrigeration cycle. The high pressure gas refrigerant discharged from the compressor 8 is sent to the indoor unit 3 through the four-way switching valve 10, the gas side stop valve 14 and the gas refrigerant connection pipe 5 .

The high-pressure gaseous refrigerant radiates heat, in the indoor heat exchanger 51, exchanging heat with indoor air supplied as a cooling source by the indoor fan 52, and becomes a high-pressure liquid refrigerant. Accordingly, the air passing through the indoor heat exchanger 51 is heated, and heating of the interior of a room is carried out. The high-pressure liquid refrigerant which has radiated heat in the indoor heat exchanger 51 is sent to the outdoor unit 2 through the liquid refrigerant connection pipe 4.

The high-pressure liquid refrigerant sent to the outdoor unit 2 is decompressed at a low pressure of the refrigeration cycle in the outdoor expansion valve 12 through the liquid-side stop valve 13 and becomes a low-pressure refrigerant. in a biphasic gas-liquid state. The low-pressure refrigerant in the decompressed gas-liquid two-phase state in the outdoor expansion valve 12 is evaporated, in the outdoor heat exchanger 11 which functions as a refrigerant evaporator, exchanging heat with outdoor air supplied as a heating source by the outdoor fan 15, thus becoming a low-pressure gaseous refrigerant. The low-pressure gaseous refrigerant is sucked back into the compressor 8 through the switching valve 10 four-way valve and accumulator 7. During a heating operation, refrigerant circulates in refrigerant circuit 6 as described above.

(5) Features

(5-1)

In general, the rate of heat transfer from the inner fins of an indoor heat exchanger can be increased as the interval with which the inner flat tubes are arranged is reduced. However, by decreasing the interval with which the inner flat tubes are arranged, the air flow rate passing between the inner flat tubes increases and causes dew condensation water to be easily dispersed. When the height of each inner flat tube in the up-down direction is large, the airflow rate passing between the inner flat tubes is similarly increased and causes dew condensation water to be easily dispersed. When the interval with which the inner flat tubes are arranged is increased, the rate of heat transfer from the inner fins decreases. Accordingly, it is required to lower the evaporation temperature of the refrigerant in the indoor heat exchanger, which creates an environment in which dew condensation water is easily generated.

On the contrary, the indoor heat exchanger 51 of the present embodiment and the air conditioning apparatus 1 including the indoor heat exchanger 51 employ the indoor heat exchanger and the air conditioning apparatus which meet the ratio of 4.0 < DP/HT < 10.0 where HT represents the height of each inner flat tube 55 in the up-down direction and DP represents the pitch of the plurality of inner flat tubes 55 in the up-down direction. From analysis data in which the values of DP and HT are varied, it becomes clear that the aforementioned setting of the DP/HT value of the indoor heat exchanger 51 to be in the numerical range is desirable for suppression of dew condensation water.

In other words, the aforementioned setting of the DP/HT value of the indoor heat exchanger 51 to 4.0 or more prevents the flow rate of the airflow flowing to cross the indoor fins 60 from increasing excessively. Accordingly, even when the indoor fan 52 is used with an increased air volume, it is possible to prevent dew condensation water from being scattered from the leeward end because the air flow is large.

In addition, setting the DP/HT value of the indoor heat exchanger 51 to 10.0 or less makes a region remote from the inner flat tubes 55 among the region of the inner fins 60 small and can make it improve the heat transfer rate of the indoor fins 60. Therefore, the need to lower the evaporation temperature of the refrigerant of the indoor heat exchanger 51 to ensure the capacity thereof is suppressed. Thus, by making dew condensation water not easily generated, suppression of scattering of dew condensation water from the indoor fins 60 is enabled, even when the indoor fan 52 is used with its increased air volume.

When the indoor heat exchanger 51 is configured to satisfy the ratio of 4.6 < DP/HT < 8.0, accentuation of the dew condensation scattering suppressing effect is enabled.

(5-2)

Generally, in an outdoor heat exchanger used in an outdoor unit of an air conditioning apparatus, airflow resistance is easily increased by frost formation on outdoor fins when the outdoor heat exchanger functions as a refrigerant evaporator. Therefore, the pitch of the outer flat tubes is required to be wide. If a heat exchanger having a structure identical to the structure of an outdoor heat exchanger such that it has a structure in which the pitch of flat tubes is wide is applied to an indoor heat exchanger, the heat transfer rate of the inner fins decreases due to the wide pitch of the flat tubes, which requires a decrease in the evaporation temperature of the refrigerant in the indoor heat exchanger and makes dew condensation water easily generated.

On the contrary, the indoor heat exchanger 51 of the present embodiment and the air conditioning apparatus 1 including the indoor heat exchanger 51 satisfy a relationship in which the DP/HT value of the indoor heat exchanger 51 is smaller. that the value of DP/HT of the outdoor heat exchanger 11 where HT represents the height of each of the flat tubes 90 and 55 in the up-down direction and DP represents the pitch of the plurality of flat tubes 90 and 55 in the top down direction.

Therefore, the heat transfer rate of the inner fins 60 is improved in the inner heat exchanger 51, in which a dew condensation water scattering problem is easily caused, while the formation of frost is suppressed. in the outdoor heat exchanger 11, in which the dew condensation water scattering problem does not easily occur, when the outdoor heat exchanger 11 is used as an evaporator, which eliminates the need to lower the evaporation temperature of the refrigerant of the indoor heat exchanger 51 when the indoor heat exchanger 51 is used as an evaporator and it is achieved that dew condensation water is not easily generated. Accordingly, suppression of scattering of dew condensation water is enabled.

(5-3)

The indoor heat exchanger 51 of the present embodiment includes the windward heat exchange section 70 and the leeward heat exchange section 80 and employs a structure in which at least two rows or more of the inner flat tubes are arranged. 55.

Accordingly, from the dew condensation water that is generated in the indoor heat exchanger 51, the dew condensation water that has been generated in the windward heat exchange section 70 is easily guided to move downward over a part between windward heat exchange section 70 and leeward heat exchange section 80 or leeward heat exchange section 80 and must be drained. Furthermore, the leeward heat exchange section 80 is supplied with air whose degree of dryness is increased by dew condensation water being generated in the windward heat exchange section 70 when it passes through the heat exchange section 70 windward. Therefore, it is possible to make the volume of the dew condensation water that is generated in the leeward heat exchange section 80 small and to suppress the scattering of dew condensation from the leeward side end of the section. 80 leeward heat exchange.

(5-4)

In the indoor heat exchanger 51 of the present embodiment, the inner fins 60 each include the inner continuous part 64 on the leeward side of the inner flat tubes 55. Therefore, the dew condensation water which has been generated in the inner flat tubes 55 is easily drained by being guided to move downwards over the inner continuous portions 64 of the inner fins 60 positioned along the downstream side in the airflow direction. Accordingly, suppression of scattering of dew condensation water from the downstream side ends of the inner fins 60 in the airflow direction is enabled.

In particular, in the indoor heat exchanger 51 of the present embodiment, the structure in which the two rows or more of the inner flat tubes 55 are arranged includes the inner continuous parts 64 on the downstream side of the inner fins 60. of section 80 of the leeward heat exchange. Therefore, drainage of dew condensation generated is enabled to increase while generation of dew condensation water at the downstream side ends of the inner fins 60 is suppressed.

(5-5)

The indoor heat exchanger 51 of the present embodiment satisfies the relationship of 0.2 < WL/WF < 0.5 where WF represents the length of each inner fin 60 in the airflow direction and WL represents the length of each inner continuous part 64 in the direction of the airflow. By thus setting the value of WL/WF to 0.2 or more on the inner fins 60, the width of each inner continuous part 64 is sufficiently guaranteed in the airflow direction, and it is achieved that the dew condensation water that generated in the indoor heat exchanger 51 is easily drained down through the continuous inner parts 64. Furthermore, by setting the value of WL/WF to 0.5 or less in the inner fins 60, it is achieved that a region, between the region of the inner fins 60, which is far from the inner flat tubes 55 and which does not easily contribute to the improvement of the heat transfer performance is small and, therefore, the suppression of the costs of material while maintaining the performance of the 60 inner fins.

In particular, by setting the value of WL/WF of the inner fins 60 to 0.2 or more while the inner continuous portions 64 of the inner fins 60 are positioned on the downstream side in the airflow direction of the inner flat tubes 55, it is possible to increase the drainage of dew condensation water that has been generated in the inner flat tubes 55 through the inner continuous parts 64.

(5-6)

The indoor heat exchanger 51 of the present embodiment has, in each inner fin 60, the main slits 62 and the continuous locating slits 63 which are cut and raised to open in the direction of the air flow. Accordingly, the air supplied to the indoor heat exchanger 51 is enabled to sufficiently contact the indoor fins 60. Therefore, it is allowed to fully utilize an air heat source.

The upper ends of the main slots 62 and continuous location slots 63 are arranged to be positioned near the bottoms of the inner flat tubes 55 which are positioned directly above. The dew condensation water that has been generated in the inner flat tubes 55 positioned directly above is easily caught and guided to move downward, which enables improved drainage. In particular, by a design such as illustrated in Fig. 12 so that the distance DS between the part where the elevation of the fin collar parts 65a begins with respect to the main surfaces 61 of the inner fins 60 and the the part where the elevation of the main grooves 62 of the inner fins 60 on the side of the flat surfaces 55b of the lower side of the inner flat tubes 55 begins is 1 mm or less, it is It is possible to prevent dew condensation water from remaining on the side of the flat surfaces 55b of the bottom side of the inner flat tubes 55 and to improve the drainage performance.

(6) Modification

(6-1) Modification A

The aforementioned embodiment has been described by presenting an example in which the downstream side end of each inner fin 60 has a flat shape.

However, the shape of the downstream side end of each inner fin 60 is not limited thereto. For example, inner fins 60a each including a water guide rib 99 extending along the downstream end in the airflow direction can be used as described below. continuation.

In Fig. 13, the positional relationship between the inner fins 60a and the inner flat tubes 55 is illustrated. In Fig. 14, the water guiding rib 99 is illustrated along a part, of the section B-B of Fig. 13, in the vicinity of the downstream side in the direction of the air flow.

As with the aforementioned embodiment, the indoor heat exchanger 51 according to the modification A also includes the windward heat exchange section 70 and the leeward heat exchange section 80. The inner fins 60a of the windward heat exchange section 70 and the leeward heat exchange section 80 each have the water guide rib 99 extending vertically along the downstream end at the airflow direction of the inner continuous part 64 arranged on the downstream side in the airflow direction. As illustrated in Fig. 14, the water guide rib 99 is formed so as to taper in the plate thickness direction of each inner fin 60a with respect to the main surface 61 around the guide rib 99. of water. Each water guide rib 99 is preferably lowered by more than the plate thickness of each inner fin 60a but is not limited thereto.

Therefore, the arrangement of the water guide ribs 99 on the inner fins 60a causes dew condensation water that has been generated in the indoor heat exchanger 51 to be trapped in the water guide ribs 99 and makes that dew condensation water is easily guided to move downward along the water guiding ribs 99. Accordingly, dew condensation water is prevented from reaching the leeward side ends of the inner fins 60a, which makes it possible to sufficiently suppress scattering of dew condensation water.

Preferably, each water guide rib 99 is arranged, in the inner continuous part 64 of each inner fin 60a, on the downstream side from the center of the width in the airflow direction. More preferably, each water guide rib 99 is arranged at a location having a width within 20% of the width of the inner continuous part 64 in the direction of airflow, from the downstream side end in the direction of air flow. of the air flow.

In the inner fins 60a on each of which the water guide rib 99 is arranged, it is particularly preferable that the ratio of the width WL of the inner continuous part 64 of each inner fin 60 in the flow direction of air and the width WF of each inner fin 60 in the direction of the airflow satisfies the relationship of 0.2 < WL/WF.

(6-2) Modification B

The aforementioned embodiment has been described by presenting an example in which the indoor heat exchanger 51 includes the windward heat exchange section 70 and the leeward heat exchange section 80 and in which the inner flat tubes 55 are juxtaposed. in two rows.

However, the number of rows along which the inner flat tubes 55 included in the indoor heat exchanger 51 are arranged side by side in the air flow direction is not limited to two. The rows may be a plurality of rows of three or more. Therefore, increasing the number of rows of the inner flat tubes 55 makes it possible to more effectively suppress the scattering of dew condensation water from the downstream side end of the indoor heat exchanger 51 in the airflow direction.

(6-3) Modification C

The aforementioned embodiment has been described by presenting an example in which, in the indoor heat exchanger 51, the plurality of inner flat tubes 55 belonging to the windward heat exchange section 70 and the plurality of inner flat tubes 55 belonging to the leeward heat exchange section 80 are arranged to overlap each other when viewed in the direction of the air flow.

However, the indoor heat exchanger 51 is not limited to it. The plurality of inner flat tubes 55 belonging to the heat exchange section on the other windward side and the plurality of inner flat tubes 55 belonging to the heat exchange section on the other leeward side can be arranged so that they do not overlap each other when viewed in the direction of the airflow. Consequently, it becomes possible for both the inner flat tubes 55 positioned on the windward side and the inner flat tubes 55 positioned on the leeward side to be subjected to a sufficient air flow.

(6-4) Modification D

The aforementioned embodiment has been described by presenting an example in which the inner fins 60 of the indoor heat exchanger 51 include the main slits 62 and continuous locating slits 63 which are shaped by cutting and lifting them in such a way that all of the fins Slit segments are positioned on one side in the direction of the plate thickness with respect to the main surfaces 61 of the inner fins 60.

However, the cut and raised portions formed on the inner flaps 60 are not limited to the above. Instead of the main slits 62 and continuously located slits 63, for example, the cut and raised slit segments may use a structure, called a louver, in which the windward side ends of the louver segments slit in the airflow direction are positioned on one side of the main surfaces 61 of the inner fins 60 in the direction of the thickness of the plate and in which the leeward side ends of the slit segments in the direction of the airflow are positioned on the other side of the main surfaces 61 of the inner fins 60 in the direction of the thickness of the plate.

Although embodiments and modifications of the present disclosure have been described above, it is to be understood that various changes in the forms and details thereof are possible within the scope of the claims.

Reference symbol list

1 air conditioning unit

2 Outdoor unit (outdoor unit)

3 Indoor unit (indoor unit)

11 Outdoor heat exchanger

51 Indoor heat exchanger

55 Inner flat tube (flat tube)

55c Flow channel

60 Inner fin (heat transfer fin)

62 Main cleft (part cut and raised)

63 Continuous locating slit (part cut and raised)

64 Inner continuous part (continuous part)

65 Windward part (each part positioned between the vertically juxtaposed flat tubes)

90 Outer flat tube (flat tube)

90c flow channel

91 Outer fin (heat transfer fin)

97th continuous part

97b Leeward part

Claims (5)

1. Air conditioning device (1) comprising: an indoor unit (3) including an indoor heat exchanger (51), and an outdoor unit (2) including an outdoor heat exchanger (11), the indoor heat exchanger (51) comprising: a plurality of flat tubes (55, 90) that are vertically juxtaposed and each include a flow channel (55c, 90c) that allows coolant to pass through an internal portion thereof, and a plurality of heat transfer fins (60, 91) attached to the plurality of flat tubes, wherein each of the heat transfer fins includes a vertically extending continuous portion (64, 97a) and which is continuous with portions (65, 97b) positioned between the vertically juxtaposed flat tubes, characterized in that The outdoor heat exchanger (11) includes a plurality of flat tubes (55, 90) that are vertically juxtaposed and each include a flow channel (55C, 90C) that allows coolant to pass through a inner part thereof, and a plurality of heat transfer fins (60, 91) attached to the plurality of flat tubes, wherein each of the heat transfer fins includes a vertically extending continuous part (64, 97a ) and which is continuous with parts (65, 97b) positioned between the vertically juxtaposed flat tubes, and when the height of each of the flat tubes is represented by HT and the pitch of the vertically juxtaposed flat tubes is represented by DP, the DP/HT value of the indoor heat exchanger is less than the DP/HT value of the exchanger of external heat. 2. Air conditioning apparatus (1) according to claim 1, wherein each of the flat tubes of the indoor heat exchanger includes a plurality of upstream side flat tubes arranged on an upstream side in the airflow direction, and a plurality of downstream side flat tubes bottom arranged on a downstream side in the airflow direction with respect to the flat tubes on the upstream side. 3. Air conditioning apparatus (1) according to any of claims 1 or 2, wherein the continuous part (64) of the indoor heat exchanger is positioned on a leeward side of the flat tubes in the airflow direction. 4. Air conditioning apparatus (1) according to any of claims 1 to 3, wherein each of the heat transfer fins of the indoor heat exchanger includes a raised and cut portion (62, 63) in which an up and down direction is a longitudinal direction. 5. Air conditioning apparatus (1) according to any of claims 1 to 4, in which a ratio of 4.6 < DP/HT < 8.0 of the indoor heat exchanger is met.