JP2010139115A - Heat exchanger and heat exchanger unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain favorable draining performance in both of cases when the same parallel flow type heat exchanger is used in a down-flow state and in a side-flow state. <P>SOLUTION: The heat exchanger 1 includes two header pipes 2, 3 disposed in parallel with each other at an interval, a plurality of flat tubes 4 disposed between the header pipes 2, 3 in a state that a plurality of refrigerant passages 5 disposed therein communicate with the inside of the header pipes 2, 3, and corrugated fins 6 disposed between the flat tubes 4. The flat tubes 4 are disposed so that their flat faces obliquely intersect axes of the header pipes 2, 3 when observed from the butt end direction, and the corrugated fins 6 are formed so that their surfaces have gradients of prescribed angles when the flat tubes 4 are disposed in a state that their longitudinal directions are vertically positioned. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a parallel flow type heat exchanger and a heat exchanger unit.

  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 parallel flow heat exchanger is shown in FIG. In FIG. 9, the upper side of the paper is the upper side in the vertical direction, and the lower side of the paper is the lower side in the vertical direction. In the heat exchanger 1, two horizontal header pipes 2 and 3 are arranged in parallel at a vertical interval, and a plurality of vertical flat tubes 4 are arranged at a predetermined pitch in the horizontal direction between the header pipes 2 and 3. Place with. 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 arranged so that the extrusion molding direction which is the longitudinal direction is vertical, the refrigerant flow direction of the refrigerant passage 5 is also vertical. A plurality of refrigerant passages 5 having the same cross-sectional shape and the same cross-sectional area are arranged in the depth direction of FIG. 9, so that the horizontal 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. Corrugated fins 6 are arranged between the adjacent flat tubes 4.

  The header pipes 2 and 3, the flat tube 4 and the corrugated fin 6 are all made of a metal having good heat conduction such as aluminum, the flat tube 4 is for the header pipes 2 and 3, and the corrugated fin 6 is for the flat tube 4. It is fixed by brazing or welding.

  The heat exchanger 1 shown in FIG. 9 is a so-called downflow parallel flow heat exchanger. A large number of flat tubes 4 having a longitudinal direction in the vertical direction are provided between the upper and lower header pipes 2 and 3, and corrugated fins 6 are provided between the flat tubes 4. The area is large and heat can be exchanged efficiently. The lower header pipe 3 is provided with a refrigerant inlet / outlet 7 at one end, and the upper header pipe 2 is provided with a refrigerant inlet / outlet 8 at one end opposite to the refrigerant inlet / outlet 7. The positional relationship between the refrigerant inlet / outlet 7 and the refrigerant inlet / outlet 8 shown here is merely an example, and the present invention is not limited to this. For example, a configuration in which the header pipe 2 includes the refrigerant inlet / outlet 8 at two locations on both ends is also possible.

Various structural devices have been made so far with respect to the parallel flow heat exchanger as described above. For example, in the parallel flow type heat exchanger described in Patent Document 1, a flat tube is installed to be inclined with respect to the flow direction of the cooling air, thereby reducing the thickness of the heat exchanger core. In the parallel flow type heat exchanger described in Patent Document 2, corrugated fin corrugated valleys and ridges are inclined in the depth direction of the heat exchanger, and water remaining on the fin surface during defrosting is inclined to the inclined fin surface. Along the heat exchanger.
JP 58-182092 A JP 2004-177040 A

  The parallel flow heat exchanger may be used in a down flow where the flat tube is vertical as shown in FIG. 9 or may be used in a side flow where the flat tube is horizontal. An object of this invention is to be able to obtain favorable drainage property, even when the same parallel flow type heat exchanger is used in a down flow or a side flow.

  In order to achieve the above object, the present invention provides a plurality of header pipes arranged in parallel at intervals, and a plurality of refrigerant pipes arranged between the plurality of header pipes and provided in the header pipe. In the heat exchanger having a flat tube communicated with the inside of the tube and a corrugated fin disposed between the flat tubes, the flat tube has a flat surface when the header is viewed from the direction of the mouth. The corrugated fins are arranged so as to cross obliquely with respect to the axis of the pipe, and the corrugated fin is formed so that the surface forms a gradient of a predetermined angle when the flat tube is arranged with the longitudinal direction as the vertical direction. It is characterized by.

  According to this configuration, when used in downflow, condensed water and defrost water flow down to the outside along the surface of the flat tube whose longitudinal direction is the vertical direction and along the gradient of the surface of the corrugated fin. Since it does not stay on the surface of the corrugated fin, the cross-sectional area of the air flow passage is narrowed by water, and the heat exchange performance is not deteriorated. Even in the case of side flow, because the surface of the flat tube and the corrugated fin fixed to it have a gradient, the condensed water and defrost water are drained smoothly. The heat exchange performance is not reduced.

  In the heat exchanger configured as described above, the corrugated fin is divided into an upwind corrugated fin and a leeward corrugated fin at an intermediate portion of the depth of the flat tube in the airflow direction, and the upwind corrugated fin and the leeward corrugated fin are opposite to each other. It is preferable to have the following gradient.

  With such a configuration, since the fin surfaces of the leeward corrugated fin and the leeward corrugated fin each have a gradient, the corrugated fin as a whole extends in the direction of air flow, and the heat dissipation area And heat exchange performance is improved.

  In addition, the present invention is a heat exchanger unit in which two heat exchangers having the above-described configuration are arranged close to each other, with one being the windward heat exchanger and the other being the leeward heat exchanger.

  According to this configuration, a heat exchange unit having a large heat radiation area and high heat exchange performance as a whole can be obtained. In addition, regarding the attitude of the leeward side heat exchanger and the leeward side heat exchanger, both the down flow pattern, the both side flow pattern, the upwind side down flow, and the leeward side There are four possible patterns: a side flow pattern, a windward side flow, and a leeward downflow pattern. Any of these patterns can smoothly drain condensed water and defrost water. .

  In the heat exchanger unit configured as described above, it is preferable that the corrugated fins of the upwind heat exchanger and the corrugated fins of the leeward heat exchanger have gradients in opposite directions.

  According to this configuration, the corrugated fins of the leeward heat exchanger and the corrugated fins of the leeward heat exchanger have respective gradient surfaces, so that the corrugated fins as a whole extend in the air flow direction. Thus, the heat radiation area is increased and the heat exchange performance is improved.

  According to the present invention, even if the same heat exchanger is used for downflow or sideflow, condensed water and defrost water can be drained smoothly, and the cross-sectional area of the air flow passage is narrowed by water. Heat exchange performance is not reduced.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 is a front view when a parallel flow type heat exchanger is used in a down flow, FIG. 2 is a partially enlarged horizontal sectional view of the parallel flow type heat exchanger of FIG. 1, and FIG. 3 is a parallel flow type heat exchanger of FIG. FIG. 4 is a front view of the parallel flow heat exchanger used in a side flow, and FIG. 5 is a vertical cross sectional view of the parallel flow heat exchanger of FIG. Components common to the conventional structure shown in FIG. 9 are denoted by the same reference numerals as those used in FIG. 9, and description thereof is omitted.

  Since the heat exchanger 1 in FIG. 1 is used in a down flow, the header pipes 2 and 3 are arranged in a horizontal state, and the flat tube 4 is arranged with the longitudinal direction set as the vertical direction. 1 and 3, the flat tube 4 is in a vertical state, but may be in an inclined state. It is only necessary to maintain the relationship that the upper header pipe 2 is higher than the lower header pipe 3. The arrows in FIG. 3 indicate the airflow direction of the heat exchange airflow that passes between the flat tubes 4.

  For convenience of explanation, in the present specification, the end face of the flat tube 4 in which a plurality of refrigerant passages 5 are arranged side by side is referred to as “Kiguchi” in comparison with the name of the cut surface in which the annual rings can be seen. The flat tube 4 is arranged so that the flat surface obliquely intersects with the axes of the header pipes 2 and 3 when viewed from the direction of the mouth as shown in FIG. The corrugated fins 6 fixed to the flat tube 4 by brazing or welding in a state in which the flat folds of the flat tube 4 are in close contact with the flat surface of the flat tube 4 have a parallelogram from the viewpoint of the flat tube 4 seen from the direction of the mouth. Yes. The corrugated fin 6 is formed so that the surface forms a gradient of a predetermined angle as shown in FIG. 3 when the flat tube 4 is arranged with the longitudinal direction as the vertical direction, that is, when used in downflow.

  When the refrigerant flows through the heat exchanger 1 while blowing air with a fan (not shown), in the operation mode in which the heat exchanger 1 is used as an evaporator (for example, outdoor of a separate air conditioner composed of an indoor unit and an outdoor unit) When the heat exchanger 1 is used to perform a heating operation, the heat exchanger 1 acts as an evaporator.) The heat exchanger 1 takes heat from the air and conversely releases cold energy into the air. When the operation of taking the heat from the air is continued, moisture in the air is condensed on the surface of the flat tube 4 and the surface of the corrugated fin 6.

  When the heat exchanger 1 is used in a down flow, the surface of the flat tube 4 becomes vertical or close to it, and even if condensed water adheres, it flows down quickly and drops from the header pipe 3. Condensed water adhering to the surface of the corrugated fins 6 also moves to the lower edge due to the gradient of the surface of the corrugated fins 6 and drops from there. Since the condensed water does not stay on the surfaces of the flat tubes 4 and the corrugated fins 6 in this way, the cross-sectional area of the air flow passage is narrowed by a bridge phenomenon (stretching of the water film) due to the surface tension of water, and heat exchange performance There will be no decline. The same can be said for defrosted water obtained by melting frost on the surface of the heat exchanger 1 in the defrosting operation.

  When the heat exchanger 1 of FIG. 1 is rotated 90 ° counterclockwise, the state of FIG. 4 is obtained. This time, the header pipes 2 and 3 have the longitudinal direction set in the vertical direction, and the flat tube 4 becomes horizontal. That is, the heat exchanger 1 is used in a side flow.

  When the heat exchanger 1 is used in the side flow, the flat tube 4 arranged so that the flat plane obliquely intersects with the axis of the header pipes 2 and 3 is in a state where the surface is inclined as shown in FIG. Become. The corrugated fins 6 fixed thereto are also in a state where a gradient is given to the folds of the ridges. For this reason, the dew condensation water and defrost water adhering to the surface of the flat tube 4 move from a high site | part to a low site | part according to the gradient of the surface, and dripping from the lower edge. Condensation water and defrost water adhering to the surface of the corrugated fins 6 also flow down to the lowest part of the corrugated fin 6 and then move from a higher part to a lower part according to the crease slope of the corrugated fin 6, and from the lower edge. Dripping down. Thus, since dew condensation water and defrost water do not stay on the surface of the flat tube 4 or the corrugated fin 6, the cross-sectional area of the air flow passage is narrowed by a bridge phenomenon due to the surface tension of water, and the heat exchange performance is reduced. There is nothing.

  The gradient of the corrugated fin 6 can be selected in the range of 5 ° to 40 °. When the gradient becomes stiff, the heat exchange area increases and drainage becomes easier, while resistance to air flow is good. The angle at which the flat surface of the flat tube 4 intersects the axis of the header pipes 2 and 3 may be determined appropriately through experiments.

  As described above, the heat exchanger 1 according to the present invention can be used for both downflow and sideflow, and a downflow or sideflow heat exchanger in consideration of drainage is manufactured with the same mold. Therefore, the manufacturing cost of the heat exchanger can be reduced.

  A second embodiment of the present invention is shown in FIG. FIG. 6 is a vertical cross-sectional view when the parallel flow type heat exchanger is used in the down flow.

  FIG. 6 shows a heat exchanger 1A arranged in a downflow shape. In the heat exchanger 1A of the second embodiment, the corrugated fins 6 are bisected in the air flow direction of the heat exchange air flow. That is, the flat tube 4 is divided into an upwind corrugated fin 6a and a leeward corrugated fin 6b at an intermediate portion of the depth in the airflow direction.

  The windward corrugated fin 6a has a fin surface with a downward slope toward the leeward side. The leeward side corrugated fin 6b has an upward slope toward the leeward side. The descending slope of the leeward corrugated fin 6a and the ascending slope of the leeward corrugated fin 6b have the same angle. The horizontal lengths of the windward corrugated fin 6a and the leeward corrugated fin 6b in the airflow direction are equal to each other.

  When the leeward corrugated fin 6a and the leeward corrugated fin 6b are viewed from a direction perpendicular to the air flow, a large number of V-shaped shapes appear to be arranged vertically. However, the bottom of the V shape is not closed but open. That is, the leeward corrugated fin 6a and the leeward corrugated fin 6b are not in close contact with each other but are disposed with a gap 9 therebetween. The gap 9 is set to such a size that the water droplets attached to the leeward side end portion of the leeward corrugated fin 6a and the water droplets attached to the leeward side corrugated fin 6b can be combined.

  When the refrigerant flows through the heat exchanger 1 while blowing air with a fan (not shown), in the operation mode in which the heat exchanger 1 is used as an evaporator (for example, outdoor of a separate air conditioner composed of an indoor unit and an outdoor unit) When the heat exchanger 1 is used to perform a heating operation, the heat exchanger 1 acts as an evaporator.) The heat exchanger 1 takes heat from the air and conversely releases cold energy into the air. Since the fin surfaces of the windward corrugated fins 6a and the leeward corrugated fins 6b are respectively inclined, the corrugated fins 6 as a whole are longer in the air flow direction than the case where the corrugated fins are horizontal without being inclined. It exists in the extended form, and high heat exchange performance can be obtained.

  If the operation of taking the heat from the air is continued, moisture in the air is condensed on the surface of the windward corrugated fin 6a, the surface of the leeward corrugated fin 6b, and the surface of the flat tube 4. When water droplets that were initially fine are gathered into large water droplets, they flow down along the gradient surface of the windward corrugated fin 6 a or the windward corrugated fin 6 b and reach the gap 9. If the gap 9 is wide, the water droplets will only cause a bridging phenomenon at the leeward end of the leeward corrugated fin 6a or the leeward end of the leeward corrugated fin 6b. However, the gap 9 is set to such a size that the water droplets adhering to the leeward end of the leeward corrugated fin 6a and the water droplets adhering to the leeward end of the leeward corrugated fin 6b can be combined. When the water droplets on the fin 6a and the water droplets on the leeward side corrugated fin 6b meet at the gap 9, the surface tensions of the fins 6a break together and flow out of the gap 9 without causing a bridging phenomenon. The same is true for defrosted water as well as condensed water.

  The descending slope of the leeward corrugated fin 6a and the ascending slope of the leeward corrugated fin 6b can be selected in the range of 5 ° to 40 °. When the gradient becomes stiff, the heat exchange area increases and drainage becomes easier, while resistance to air flow is good. The angle at which the flat surface of the flat tube 4 intersects the axis of the header pipes 2 and 3 may be determined appropriately through experiments.

  A third embodiment of the present invention is shown in FIGS. FIG. 7 is a vertical sectional view when the heat exchanger unit of the parallel flow type heat exchanger is used in downflow, and FIG. 8 is a vertical sectional view when the heat exchanger unit of the parallel flow type heat exchanger is used in side flow. is there.

  In the third embodiment, in order to increase the heat exchange capability, two heat exchangers 1 of the type of the first embodiment are arranged close to each other to form a heat exchanger unit HEU. One of the two heat exchangers 1 constituting the heat exchanger unit HEU is an upwind heat exchanger 1U, and all of the components are accompanied by the letter “U”. The other is the leeward side heat exchanger 1D, and all the components are accompanied by the letter “D”.

  In FIG. 7, both the windward side heat exchanger 1U and the leeward side heat exchanger 1D are arranged in a down flow. The corrugated fin 6U of the upwind heat exchanger 1U is extended to the leeward side of the corrugated fin 6 of the first embodiment, and the corrugated fin 6D of the leeward side heat exchanger 1D is more than the corrugated fin 6 of the first embodiment. Is also extended to the windward side. And the corrugated fin 6U has a fin surface with a downward slope toward the leeward side, and the corrugated fin 6D has an upward slope with the fin surface toward the leeward side. The downward slope of the corrugated fin 6U and the upward slope of the corrugated fin 6D have the same angle. The horizontal lengths of the corrugated fins 6U and the corrugated fins 6D in the airflow direction are equal to each other.

  The windward side heat exchanger 1U and the leeward side heat exchanger 1D do not need to be separately designed. If two of the same shape are prepared, and one side is reversed and matched with the other, the heat exchanger unit HEU of FIG. 7 can be obtained.

  When the corrugated fins 6U and the corrugated fins 6D are viewed from a direction perpendicular to the air flow, a large number of V-shaped shapes appear to be lined up and down. However, the bottom of the V shape is not closed but open. That is, the corrugated fins 6U and the corrugated fins 6D are not in close contact but are arranged with a gap 10 therebetween. The gap 10 is set to such a size that the water droplets adhering to the leeward end of the corrugated fin 6U and the water droplets adhering to the leeward end of the corrugated fin 6D can be combined.

  When the refrigerant flows through the heat exchanger unit HEU while blowing with a fan (not shown), in the operation mode in which the heat exchanger unit HEU is used as an evaporator (for example, a separate air conditioner composed of an indoor unit and an outdoor unit) When the heat exchanger unit HEU is used in the outdoor unit and heating operation is performed, the heat exchanger unit HEU acts as an evaporator), the heat exchanger unit HEU takes heat from the air, and conversely, cool heat is brought into the air. discharge. Since the corrugated fins 6U and 6D have a slope on the fin surface, the corrugated fins as a whole extend longer in the air flow direction as compared with the corrugated fins that are horizontal without any gradient. Thus, high heat exchange performance can be obtained.

  When the operation of taking heat away from the air is continued, moisture in the air is condensed on the surfaces of the corrugated fins 6U and 6D and the surfaces of the flat tubes 4U and 4D. When water droplets that were initially fine gathered into large water droplets, they flow down along the gradient surfaces of the corrugated fins 6U and 6D and reach the gap 10. If the gap 10 is wide, the water droplets will only cause a bridging phenomenon at the leeward end of the corrugated fin 6U or the leeward end of the corrugated fin 6D. However, the gap 10 is set to such a size that the water droplets adhering to the leeward end of the corrugated fin 6U and the water droplets adhering to the leeward end of the corrugated fin 6D can be combined. When the water droplets of the fins 6D meet at the gap 10, they break up and combine with each other and flow out of the gap 10 without causing a bridging phenomenon. The same is true for defrosted water as well as condensed water.

  The downward slope of the corrugated fin 6U and the upward slope of the corrugated fin 6D can be selected in the range of 5 ° to 40 °. When the gradient becomes stiff, the heat exchange area increases and drainage becomes easier, while resistance to air flow is good. The angle at which the flat surface of the flat tube 4U intersects the axis of the header pipes 2U and 3U and the angle at which the flat surface of the flat tube 4D intersects the axis of the header pipes 2D and 3D may be determined appropriately through experiments.

  FIG. 8 shows an embodiment in which both the windward side heat exchanger 1U and the leeward side heat exchanger 1D are side flows. The windward side heat exchanger 1U and the leeward side heat exchanger 1D are such that the surface of the flat tube 4U becomes a downward slope toward the leeward side in the windward side heat exchanger 1U, and the surface of the flat tube 4D in the leeward side heat exchanger 1D. Is arranged so as to have an upward slope toward the leeward side. The fold of the corrugated fin 6U fixed to the flat tube 4U has a downward slope toward the leeward side, and the fold of the corrugated fin 6D fixed to the flat tube 4D has an upward slope toward the leeward side. The gap 10 between the leeward end of the corrugated fin 6U and the leeward end of the corrugated fin 6D is also attached to the water droplets attached to the leeward end of the corrugated fin 6U and the windward end of the corrugated fin 6D. The size is set such that the combined water droplets can occur.

  Condensation water and defrost water adhering to the surfaces of the flat tubes 4U and 4D move from a high part to a low part according to the gradient of the surface, and drip from the lower edge. Condensation water and defrost water adhering to the surfaces of the corrugated fins 6U and 6D also flow down to the lowest part of the corrugated fins 6U and 6D, and then move from a higher part to a lower part according to the fold crease gradient. When the water reaches the gap 10, the water droplets adhering to the leeward end portion of the corrugated fin 6U and the water droplets adhering to the leeward end portion of the corrugated fin 6D are generated, and flow out of the gap 10 without causing a bridging phenomenon. . In this way, the condensed water and defrost water do not stay on the surface of the flat tubes 4U, 4D and the corrugated fins 6U, 6D, so the cross-sectional area of the air flow passage is narrowed by the bridge phenomenon due to the surface tension of the water, and heat exchange performance There will be no decline.

  FIG. 7 shows a downflow pattern for both the windward side heat exchanger 1U and the leeward side heat exchanger 1D, and FIG. 8 shows a sideflow pattern for both the windward side heat exchanger 1U and the leeward side heat exchanger 1D. Although shown, a pattern in which the upwind heat exchanger 1U is downflow and the downwind heat exchanger 1D is sideflow, or the upwind heat exchanger 1U is sideflow and the downwind heat exchanger 1D is downflow is also possible. .

  FIGS. 7 and 8 show the case where the total number of heat exchangers constituting the heat exchanger unit HEU is two. However, the heat exchanger unit HEU may be composed of more than two heat exchangers. it can. In that case, if two adjacent heat exchangers are taken up, one side will be the windward side heat exchanger and the other side will be the leeward side heat exchanger. What is necessary is just to adjust the relationship of the inclination of the flat tube in the case of using.

  As mentioned above, although each embodiment of the present invention was described, the scope of the present invention is not limited to this, and various modifications can be made without departing from the spirit of the invention.

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

The front view in the case of using the parallel flow type heat exchanger which concerns on 1st Embodiment by a down flow Partial enlarged horizontal sectional view of the parallel flow heat exchanger of FIG. Vertical sectional view of the parallel flow heat exchanger of FIG. The front view in the case of using the parallel flow type heat exchanger which concerns on 1st Embodiment by a side flow Vertical sectional view of the parallel flow heat exchanger of FIG. Vertical sectional view when the parallel flow heat exchanger according to the second embodiment is used in a down flow Vertical sectional view when the heat exchanger unit of the parallel flow type heat exchanger according to the third embodiment is used in downflow Vertical sectional view when the heat exchanger unit of the parallel flow type heat exchanger according to the third embodiment is used in a side flow Vertical sectional view showing the schematic structure of a conventional parallel flow heat exchanger

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat exchanger 2, 3 Header pipe 4 Flat tube 5 Refrigerant passage 6 Corrugated fin 7, 8 Refrigerant inlet / outlet 1A Heat exchanger 6a Upwind corrugated fin 6b Downward corrugated fin HEU Heat exchanger unit 1U Upwind heat exchanger 1D Downward Side heat exchanger

Claims (4)

A plurality of header pipes arranged in parallel at intervals, a plurality of flat tubes arranged between the plurality of header pipes, and having a plurality of refrigerant passages provided therein communicated with the interior of the header pipe; In a heat exchanger provided with corrugated fins arranged between flat tubes,
The flat tube is arranged so that the flat surface obliquely intersects with the axis of the header pipe when viewed from the direction of the mouth, and the corrugated fin is arranged such that the flat tube has the longitudinal direction as the vertical direction. The heat exchanger is characterized in that when formed, the surface has a predetermined angle gradient.   The corrugated fin is divided into an upwind corrugated fin and a leeward corrugated fin at an intermediate portion in the airflow direction depth of the flat tube, and the upwind corrugated fin and the leeward corrugated fin have gradients opposite to each other. The heat exchanger according to claim 1.   A heat exchanger unit comprising two heat exchangers according to claim 1 arranged close to each other, with one being the windward heat exchanger and the other being the leeward heat exchanger.   4. The heat exchanger unit according to claim 3, wherein the corrugated fins of the upwind heat exchanger and the corrugated fins of the leeward heat exchanger have gradients in opposite directions.

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