JP2012093010A - Heat exchanger and air conditioner mounted with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of water splash even if condensed water adheres to a parallel flow type heat exchanger of a side flow system.SOLUTION: The heat exchanger 1 is provided with: two header pipes 2, 3 disposed parallel to each other with a spacing therebetween; flat tubes 4 disposed between the header pipes 2, 3 and having therein refrigerant paths 5 connected to the insides of the header pipes 2, 3; and fins 6 disposed between the flat tubes 4. In the flat tubes 4, intermediate portions in the length direction are set higher than the both ends.

Description

  The present invention relates to a side flow parallel flow heat exchanger and an air conditioner equipped with the heat exchanger.

  A parallel flow type heat in which a plurality of flat tubes are arranged between a plurality of header pipes so that a plurality of refrigerant passages in the flat tubes communicate with the inside of the header pipe, and fins such as corrugated fins are arranged between the flat tubes. Exchangers are widely used in outdoor units of car air conditioners and building air conditioners.

  An example of a conventional side flow parallel flow type heat exchanger is shown in FIG. The heat exchanger 1 includes two header pipes 2 and 3 and a plurality of flat tubes 4 arranged therebetween. In FIG. 8, the header pipes 2 and 3 extend in the vertical direction and are arranged in parallel in the horizontal direction at intervals, and the flat tubes 4 extend in the horizontal direction and are arranged at a predetermined pitch in the vertical direction. Needless to say, the parallel flow type heat exchanger 1 is installed at various angles in accordance with design requirements at the stage of actually mounting on equipment, and there are many cases where exact “vertical” and “horizontal” do not apply.

  The flat tube 4 is an elongated molded product obtained by extruding a metal, and a refrigerant passage 5 through which a refrigerant flows is formed. Since the flat tube 4 is disposed so that the extrusion direction, which is the longitudinal direction, is horizontal, the refrigerant flow direction of the refrigerant passage 5 is also horizontal. A plurality of refrigerant passages 5 having the same cross-sectional shape and cross-sectional area are arranged in the depth direction of FIG. 8, and therefore, the vertical cross section of the flat tube 4 has a harmonica shape. Each refrigerant passage 5 communicates with the inside of the header pipes 2 and 3. Fins 6 are arranged between adjacent flat tubes 4. Here, corrugated fins are used as the fins 6, but plate fins may be used.

  The header pipes 2 and 3, the flat tubes 4, and the fins 6 are all made of a metal having good heat conductivity such as aluminum, the flat tubes 4 are brazed to the header pipes 2 and 3, and the fins 6 are brazed to the flat tubes 4. Or it is fixed by welding.

  In the heat exchanger 1 of FIG. 8, the refrigerant outlets 7 and 8 are provided only on the header pipe 3 side. Two partition plates 9a and 9c are provided in the header pipe 3 at intervals in the vertical direction. Inside the header pipe 2, the partition plates are located at a height intermediate between the partition plates 9a and 9c. 9b is provided.

  When the heat exchanger 1 is used as an evaporator, the refrigerant flows in from the lower refrigerant inlet / outlet port 7 as indicated by solid line arrows in FIG. The refrigerant entering from the refrigerant inlet / outlet 7 is blocked by the partition plate 9 a and travels toward the header pipe 2 via the flat tube 4. This refrigerant flow is represented by a left-pointing block arrow. The refrigerant that has entered the header pipe 2 is blocked by the partition plate 9 b and travels to the header pipe 3 via another flat tube 4. This refrigerant flow is represented by a right-pointing block arrow. The refrigerant that has entered the header pipe 3 is dammed up by the partition plate 9 c, and further travels toward the header pipe 2 via another flat tube 4. This refrigerant flow is represented by a left-pointing block arrow. The refrigerant that has entered the header pipe 2 is folded back and travels again to the header pipe 3 via another flat tube 4. This refrigerant flow is represented by a right-pointing block arrow. The refrigerant that has entered the header pipe 3 flows out from the refrigerant inlet / outlet 8. In this way, the refrigerant follows the zigzag path and flows from the bottom to the top. Although the case where the number of partition plates is 3 is shown here, this is only an example, and the number of partition plates and the number of times the resulting refrigerant flow may be folded may be set as desired. it can.

  When the heat exchanger 1 is used as a condenser, the refrigerant flow is reversed. That is, the refrigerant enters the header pipe 3 from the refrigerant inlet / outlet 8 as shown by a dotted arrow in FIG. 8, is dammed by the partition plate 9c and goes to the header pipe 2 via the flat tube 4, and is dammed by the partition plate 9b in the header pipe 2. It heads to the header pipe 3 via another flat tube 4, and the header pipe 3 is dammed by a partition plate 9 a, then goes to the header pipe 2 again via another flat tube 4, and is folded back by the header pipe 2 to make another flat It flows from the top to the bottom following the zigzag path in which it goes to the header pipe 3 again via the tube 4 and flows out from the refrigerant inlet / outlet 7 as indicated by the dotted line arrow.

  When the heat exchanger is used as an evaporator, moisture in the atmosphere condenses on the surface of the heat exchanger that has become a low temperature, and condensed water is generated. In the parallel flow type heat exchanger, when the condensed water stays on the surface of the flat tube or the fin, the cross-sectional area of the air flow passage is narrowed by the water, and the heat exchange performance is deteriorated.

  When the temperature is low, the condensed water turns into frost on the surface of the heat exchanger. Frost can travel to ice. In the present specification, the term “condensed water” is used to include water in which such frost and ice are melted, so-called defrosted water.

  When condensed water is generated and accumulated in the side flow parallel flow heat exchanger, the following problems occur. As shown in FIG. 9, when the side flow type parallel flow heat exchanger 1 is placed so that the surface on which the condensed water is concentrated faces downward, the condensed water accumulated at the ends of the fins 6 It drops from the corner of the fin 6 before it changes over to the fin 6 of the step. When the heat exchanger 1 is installed in an indoor unit of an air conditioner and a crossflow fan is installed under the heat exchanger 1, a “water jump” in which water droplets are scattered in the airflow blown by the crossflow fan Occur and cause discomfort to the user.

  Accordingly, various measures for draining condensed water before water jumps have been proposed. Examples thereof can be seen in Patent Documents 1 and 2.

  In the heat exchanger described in Patent Document 1, a drainage guide that comes into contact with the fins is disposed on the condensed water condensing side. The drainage guide is made of a linear member, is inclined with respect to the flat tube, and at least one of both ends is led to the lower end side or the side end side of the heat exchanger.

  In the heat exchanger described in Patent Document 2, the guide plate is disposed in contact with the fins on the downstream side of the air blowing. The dew adhering to the surface of the heat exchanger moves downstream by blowing and adheres to the guide plate, and falls freely by its weight.

JP 2007-285673 A Japanese Patent Laid-Open No. 2001-263861

  In the heat exchanger described in Patent Document 1, water is guided by bringing a drainage guide made of a linear member into contact with the heat exchanger. However, when the heat exchanger is installed in a tilted state or when dirt is attached to the drainage guide, a phenomenon such as water jumping may occur without water passing through the drainage guide. Even in the heat exchanger described in Patent Document 2, when installed in an inclined state, water jumps due to water bridged between the fins.

  The present invention has been made in view of the above points, and it is an object of the present invention to prevent water from jumping even when condensed water adheres to a heat exchanger.

  According to a preferred embodiment of the present invention, a plurality of header pipes arranged in parallel at intervals, and a plurality of refrigerant pipes arranged between the plurality of header pipes are provided inside the header pipes. In a parallel flow type heat exchanger of a side flow type comprising a flat tube connected to each other and fins disposed between the flat tubes, the flat tube has a higher middle portion in the length direction than both ends. It has become.

  Moreover, the heat exchanger of the said structure WHEREIN: It is preferable that the said flat tube is equipped with the curved shape which became convex upwards.

  In the heat exchanger configured as described above, it is preferable that the flat tube is highest at a central portion in the length direction.

  In the heat exchanger configured as described above, it is preferable that the flat tube is narrower than the fin in the direction in which air passes through the heat exchanger.

  Moreover, in the heat exchanger of the said structure, it is preferable that the blocking part of an L-shaped cross section is formed in the end of the said fin in the surface at the side where condensed water collects.

  In the heat exchanger having the above-described configuration, a groove extending in the length direction is formed on the upper surface of the flat tube, and the groove is preferably located at a substantially center of the flat tube in a direction perpendicular to the length direction. .

  Further, in the heat exchanger configured as described above, the end of the fin on the surface on the side where condensed water collects protrudes from the end of the flat tube, and the end of the flat tube is formed by the protruding portions of the fins. It is preferable that a flange protruding in the gap and extending in the length direction of the flat tube is formed.

  According to a preferred embodiment of the present invention, the heat exchanger configured as described above is mounted on an outdoor unit or an indoor unit of an air conditioner.

  According to the present invention, in the parallel flow type heat exchanger of the side flow type, the flat tube has a middle portion in the length direction higher than both ends, so the condensed water generated on the surface of the flat tube or fin is flat tube. It flows toward both ends. Therefore, even if a fan is placed under the heat exchanger, the condensed water can be guided and drained to both ends of the flat tube where the vertical position does not overlap with the fan. It is possible to avoid a situation in which condensed water drops from the middle part of the water and water jumps.

It is a front view of the heat exchanger which concerns on 1st Embodiment of this invention. It is a top view of the heat exchanger of FIG. It is a fragmentary sectional view of the heat exchanger which concerns on 2nd Embodiment of this invention. It is a fragmentary sectional view of the heat exchanger which concerns on 3rd Embodiment of this invention. It is a schematic sectional drawing of the outdoor unit of the air conditioner carrying the heat exchanger which concerns on this invention. It is a schematic block diagram of the air conditioner carrying the heat exchanger which concerns on this invention, and shows the state at the time of heating operation. It is a schematic block diagram of the air conditioner carrying the heat exchanger which concerns on this invention, and shows the state at the time of air_conditionaing | cooling operation. It is a vertical sectional view showing a schematic structure of a conventional side flow type parallel flow type heat exchanger. It is a schematic sectional drawing which shows the state which inclined and placed the conventional side flow type parallel flow type heat exchanger so that the surface on the side where condensed water collects may face down.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. Components that are functionally common to the conventional structure of FIG. 8 are denoted by the same reference numerals as those used in FIG.

  In the side flow type parallel flow heat exchanger 1 according to the first embodiment, four refrigerant inlets / outlets 7 are provided in the header pipe 2, and four refrigerant inlets / outlets 8 are provided in the header pipe 3. The four refrigerant inlets / outlets 7 are combined into one by a flow divider (not shown), and the four refrigerant outlets / outlets 8 are also combined into one by a flow divider (not shown).

  The feature of the present invention is the shape of the flat tube 4. That is, when the heat exchanger 1 is arranged in such a manner that the header pipes 2 and 3 are vertical and the flat tube 4 is horizontal, the flat tube 4 is higher in the middle in the length direction than both ends. In 1st Embodiment, the intermediate part of the length direction is made high by making the flat tube 4 into the curved shape which became convex upwards. In addition, the height of the flat tube 4 is highest at the central portion in the length direction. The flat shape of the flat tube 4 is linear as shown in FIG.

  As described above, since the intermediate portion in the length direction of the flat tube 4 is made higher than both ends, the condensed water generated on the surfaces of the flat tube 4 and the fins 6 flows toward both ends of the flat tube 4. Therefore, even if a fan is placed under the heat exchanger 1, the condensed water can be guided and drained to both ends of the flat tube 4 where the vertical position does not overlap with the fan. It is possible to avoid a situation in which condensed water drops from an intermediate portion in the length direction and water jumps.

  In the direction in which air passes through the heat exchanger 1, in other words, in the direction perpendicular to the length direction and in the horizontal direction, the flat tubes 4 are narrower than the fins disposed between them. Thereby, condensed water will flow along the edge of a flat tube, and drainage efficiency will improve.

  In the first embodiment, the flat tube 4 has a curved shape that is convex upward, but may be a “f” -shaped bent shape. Moreover, although the height of the flat tube 4 became the highest in the center part of the length direction, you may comprise so that the highest point may come to the location which is biased not to the center but to the right or left.

  Further, in the first embodiment, the plurality of flat tubes 4 are all the same shape, but the shapes may be different depending on the flat tubes 4. For example, a configuration in which bending (bending) becomes deeper as the flat tube 4 positioned at the upper level, a configuration in which a bending tube and a bending tube are combined, and the like are possible.

  By adding an auxiliary structure to the heat exchanger 1 of the first embodiment, it is possible to more reliably prevent the condensed water from dripping from the intermediate portion in the length direction of the flat tube 4. An example of such a structure is shown in FIG. 3 as a second embodiment.

  In the heat exchanger 1 of the second embodiment, the blocking portion 10 is formed at the end of the flat tube 4 on the surface on the side where condensed water is collected. The blocking portion 10 includes a base portion 11 that is an extension of the flat tube 4 and a blocking wall 12 that rises from the end of the base portion 11 and has an L-shaped cross section as a whole. The blocking wall 12 covers the lower end of the fin 6 from the outside. The base portion 11 and the blocking wall 12 are not in close contact with the lower end of the fin 6, and a gap 13 is provided between the base portion 11 and the blocking wall 12.

  The blocking portion 10 may be molded separately from the flat tube 4 and may be joined to the flat tube 4 by brazing or welding, or may be integrally formed with the flat tube 4. Even when molding separately from the flat tube 4, the material of the blocking part 10 is preferably the same as that of the flat tube 4.

  In the case of molding separately from the flat tube 4, the material of the blocking portion 10 may be the same as that of the flat tube 4, but in that case, the blocking portion 10 itself is cooled and condensed, and the corner of the blocking portion 10 is formed. There is a possibility that condensed water will drip from the water. In order to prevent this, the blocking portion 10 may be molded from a material that is difficult to cool, such as a synthetic resin.

  Thus, since the blocking wall 12 which covers the lower end of the fin 6 from the outside is formed at the end of the flat tube 4 on the surface where condensed water is collected, the condensed water collected is blocked. Is guided into the inside of the fin 6 and does not drip. As a result, the condensed water can be reliably guided to both ends of the flat tube 4, and the condensed water can be prevented from falling on the fan and causing water jumps.

  A groove 14 extending in the length direction is formed on the upper surface of the flat tube 4. The groove 14 is positioned substantially at the center of the flat tube 4 in a direction perpendicular to the length direction. The depth of the groove 14 may be 10% or less of the entire thickness of the flat tube 4. Since the condensed water is guided to the both ends of the flat tube 4 through the groove 14, the drainage efficiency is improved.

  A third embodiment of the heat exchanger 1 is shown in FIG. In the heat exchanger 1 of the third embodiment, the end of the fin 6 protrudes from the end of the flat tube 4 on the surface where condensed water collects, and the end of the flat tube 4 includes the protruding portions of the fin 6. A brim 15 that protrudes into the gap is formed. The flange 15 extends in the length direction of the flat tube 4 and is located at the center of the gap in the vertical direction.

  When the flange 15 is present, it is the same as a gap between the flat tube 4 and the fin 6, and the condensed water easily flows along the flat tube 4. Thereby, drainage efficiency improves. The lowering of the hydrophilicity of the fin 6 due to the adhesion of oil does not have to be taken care of much.

  The heat exchanger 1 of each of the above embodiments can be mounted on an outdoor unit or an indoor unit of a separate air conditioner. FIG. 5 shows an example of mounting on an outdoor unit.

  The outdoor unit 20 shown in FIG. 5 includes a sheet metal housing 20a having a substantially rectangular planar shape. The long side of the housing 20a is a front surface 20F and a back surface 20B, and the short side is a left side surface 20L and a right side surface 20R. An exhaust port 21 is formed on the front surface 20F, a rear intake port 22 is formed on the rear surface 20B, and a side intake port 23 is formed on the left side surface 20L. The exhaust port 21 is made up of a set of a plurality of horizontal slit-like openings, and the rear intake port 22 and the side intake ports 23 are made up of lattice-like openings. A top plate and a bottom plate (not shown) are added to the four sheet metal members of the front surface 20F, the back surface 20B, the left side surface 20L, and the right side surface 20R to form a hexahedral-shaped housing 20a.

  Inside the housing 20a, a planar L-shaped heat exchanger 1 is disposed just inside the rear intake port 22 and the side intake port 23. In order to force heat exchange between the heat exchanger 1 and the outdoor air, a blower 24 is disposed between the heat exchanger 1 and the exhaust port 21. The blower 24 is a combination of an electric motor 24a and a propeller fan 24b. In order to improve the blowing efficiency, a bell mouth 25 surrounding the propeller fan 24b is attached to the inner surface of the front surface 20F of the housing 20a. A space inside the right side surface 20R of the housing 20a is isolated by a partition wall 26 from an air flow flowing from the rear intake port 22 to the exhaust port 21, and a compressor 27 is accommodated therein.

  In the outdoor unit 20, the windward side of the heat exchanger 1 is the condensed water condensing side. This is due to the following reason. In the outdoor unit 20, the heat exchanger 1 is installed substantially vertically without being inclined. When the heat exchanger 1 is used as an evaporator (for example, the heating operation corresponds to this), heat exchange is actively performed on the windward side rather than the leeward side, and condensed water accumulates there. Therefore, the windward side is the condensed water condensing side.

  Condensate condensed on the windward side does not flow to the leeward side. When the outside air temperature is low, the condensed water adheres to the heat exchanger 1 as frost. If the amount of frost increases, the defrosting operation will be forced, but during the defrosting operation, the blower 24 is stopped, so that the water in which the frost has melted flows and accumulates exclusively under gravity without being affected by the wind. . From these things, generation | occurrence | production of the water jump by condensed water can be prevented by applying the structure of this invention to the surface of the windward side.

  6 and 7 show an example in which the heat exchanger 1 is mounted on an indoor unit of a separate type air conditioner. The outdoor unit of the separate type air conditioner shown in FIGS. 6 and 7 includes a compressor, a four-way valve, an expansion valve, an outdoor heat exchanger, an outdoor fan, etc., and the indoor unit is an indoor heat exchanger, an indoor side Includes a blower. The outdoor heat exchanger functions as an evaporator during heating operation and functions as a condenser during cooling operation. The indoor heat exchanger functions as a condenser during heating operation and functions as an evaporator during cooling operation.

  FIG. 6 shows a basic configuration of a separate type air conditioner using a heat pump cycle as a refrigeration cycle. The heat pump cycle 101 includes a compressor 102, a four-way valve 103, an outdoor heat exchanger 104, a decompression / expansion device 105, and an indoor heat exchanger 106 connected in a loop. The compressor 102, the four-way valve 103, the heat exchanger 104, and the decompression / expansion device 105 are accommodated in the casing of the outdoor unit 110, and the heat exchanger 106 is accommodated in the casing of the indoor unit 120. An outdoor fan 107 is combined with the heat exchanger 104, and an indoor fan 108 is combined with the heat exchanger 106. The blower 107 includes a propeller fan 107a for forming a blown airflow, and the blower 108 includes a cross flow fan 108a for forming a blown airflow. The cross flow fan 108a is disposed below the heat exchanger 106 with its axis line horizontal.

  The heat exchanger 1 which concerns on this invention can be used as a component of the heat exchanger 106 of an indoor unit. The heat exchanger 106 is a combination of three heat exchangers 106A, 106B, and 106C like a roof that covers the blower 108, and any or all of the heat exchangers 106A, 106B, and 106C are combined with the heat exchanger 1. It can be.

  FIG. 6 shows a state during heating operation. At this time, the high-temperature and high-pressure refrigerant discharged from the compressor 102 enters the indoor heat exchanger 106 where it dissipates heat and condenses. The refrigerant exiting the heat exchanger 106 enters the outdoor heat exchanger 104 from the decompression / expansion device 105 and expands there, takes heat from the outdoor air, and returns to the compressor 102. The airflow generated by the indoor fan 108 promotes heat dissipation from the heat exchanger 106, and the airflow generated by the outdoor fan 107 accelerates heat absorption of the heat exchanger 104.

  FIG. 7 shows a state during cooling operation or defrosting operation. At this time, the four-way valve 103 is switched so that the refrigerant flow is reversed from that during the heating operation. That is, the high-temperature and high-pressure refrigerant discharged from the compressor 102 enters the outdoor heat exchanger 104, where it dissipates heat and condenses. The refrigerant exiting the heat exchanger 104 enters the heat exchanger 106 on the indoor side from the decompression / expansion device 105 and expands there, takes heat from the indoor air, and returns to the compressor 102. The air flow generated by the outdoor air blower 107 promotes heat dissipation from the heat exchanger 104, and the air flow generated by the indoor air blower 108 promotes heat absorption of the heat exchanger 106.

  When the heat exchanger 1 according to the present invention is used as a constituent element of the heat exchanger 106 of the indoor unit, the surface that is the leeward side of the heat exchanger 1 and also the lower surface side depending on the posture of the heat exchanger 1 is condensed water. The rally side. When the heat exchanger 1 according to the present invention is used, even if condensed water collects on the surface on the leeward side, it does not drop on the cross flow fan 108a, and water splash does not occur. Moreover, in the heat exchanger 1, a bridge phenomenon can be suppressed and an increase in ventilation resistance can be suppressed.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  The present invention is widely applicable to side flow parallel flow heat exchangers.

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2, 3 Header pipe 4 Flat tube 5 Refrigerant passage 6 Fin 7, 8 Refrigerant inlet / outlet 10 Blocking part 14 Groove 15 Head 20 Outdoor unit 110 Outdoor unit 120 Indoor unit

Claims (8)

A plurality of header pipes arranged in parallel at intervals, a plurality of flat tubes arranged between the plurality of header pipes and having refrigerant passages provided therein communicated with the inside of the header pipes, and the flat tubes In the parallel flow type heat exchanger of the side flow type provided with fins arranged between each other,
The flat tube has a middle portion in the length direction that is higher than both ends.   The heat exchanger according to claim 1, wherein the flat tube has a curved shape that protrudes upward.   The heat exchanger according to claim 1 or 2, wherein the flat tube is highest at a central portion in a length direction.   4. The heat exchanger according to claim 1, wherein the flat tube is narrower than the fin in a direction in which air passes through the heat exchanger. 5.   The heat exchanger according to any one of claims 1 to 4, wherein a blocking portion having an L-shaped cross section is formed at an end of the fin on a surface on which condensed water is collected.   6. The groove according to claim 1, wherein a groove extending in a length direction is formed on an upper surface of the flat tube, and the groove is positioned substantially at a center of the flat tube in a direction perpendicular to the length direction. The heat exchanger according to item 1.   The end of the fin on the surface where condensed water collects protrudes from the end of the flat tube, and the end of the flat tube protrudes into the gap formed by the protruding portions of the fin, and the length of the flat tube The heat exchanger according to any one of claims 1 to 6, wherein a flange extending in the vertical direction is formed.   An air conditioner in which the heat exchanger according to any one of claims 1 to 7 is mounted on an outdoor unit or an indoor unit.

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