JP2001027484A - Serpentine heat-exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a serpentine heat-exchanger having the most efficient size. SOLUTION: This heat-exchanger comprises at least a header pipe 2 on the inlet side, a header pipe 4 on the outlet side, an at least one serpentine tube 6 extending from the header pipe 2 on the inlet side and folded in a plurality of stages at intervals of a given distance and reaching the header pipe 4 on the outlet side, and a corrugated fin 7 disposed between a plurality of adjoining folded refrigerant passages consisting of the serpentine tube 6. In this case, the width of a heat-exchanger 1 in a direction of ventilation of air flowing through the corrugated fin 7 is formed in a range of approximately 35-65 mm and the height of the fine of the corrugated fin 7 is formed in a range of approximately 5-13 mm. A distance between the folded refrigerant passages of the serpentine tube 6 is set corresponding to the fin height.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an evaporator used in a refrigeration cycle using carbon dioxide as a refrigerant and a heat pump type refrigeration cycle, and is used as an evaporator or a condenser depending on the direction of the refrigerant flow. And more particularly to a serpentine heat exchanger.

[0002]

2. Description of the Related Art Japanese Utility Model Laid-Open Publication No. 57-40893 discloses a technique in which both ends of a tube formed so as to meander continuously are gathered in one place, and both ends of the tube are formed in an inlet member formed in one collecting member. And an outlet hole, and a connecting pipe is connected to the inlet hole and the outlet hole of the assembly member.

Further, Japanese Utility Model Laid-Open No. 57-82690 discloses that
Disclosed is a heat exchanger in which a flat tube is folded in multiple stages at appropriate intervals and fins are interposed therebetween. This heat exchanger is provided with a horizontal portion where the flat surface of the flat tube is horizontal at the upper and lower ends at the time of manufacturing the heat exchanger, and a connector connection having a connector at each of the horizontal portions of the flat tube. A device is provided.

Further, Japanese Utility Model Laid-Open No. 57-178993 discloses that two left and right symmetric refrigerant passages are formed by joining both ends of a left tube and a right tube to an entrance block disposed in the center, Disclosed is a vehicle capacitor in which a connection plate is provided near the tip of an inlet pipe and an outlet pipe, and the connection plate is fixed to the entrance block and the entrance pipe and the exit pipe are joined to the entrance block.

[0005]

However, in the above-mentioned serpentine-type heat exchangers, there has recently been a strong need for downsizing and thinning of the heat exchangers. Efficiency is essential. In particular, in the case of a serpentine type heat exchanger, when trying to reduce the height of the fins to reduce the size of the heat exchanger, the bending R of the tube must be reduced. Occurs.

Accordingly, an object of the present invention is to provide a serpentine heat exchanger having the most efficient dimensions.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to an inlet header pipe formed by folding a plurality of stages at a predetermined interval between an inlet header pipe into which a refrigerant flows, an outlet header pipe from which a refrigerant flows, and a predetermined interval. And at least one serpentine tube communicating with the outlet side header pipe and a corrugated fin disposed between a plurality of folded refrigerant passages formed by the serpentine tube. In the above, the width of the heat exchanger in the ventilation direction of the air flowing through the corrugated fin is formed in a range of about 35 mm to 65 mm, and the fin height of the corrugated fin is formed in a range of about 5 mm to 13 mm. The distance between the folded refrigerant passages of the serpentine tube is set to this fin height. It is to form correspondingly. This makes it possible to reduce the dimension of the serpentine tube in the stacking direction of the folded refrigerant passages and the fins and the width of the heat exchanger in the ventilation direction while maintaining the heat exchanger capacity at or above a predetermined level. Is what you can do.

Further, the present invention provides a corrugated fin having a fin pitch between a bent portion contacting one tube element and a next bent portion contacting one tube element. 8 mm or more and 5.0 m
m, and the plate thickness of the corrugated fin is desirably about 0.06 mm or more and 0.15 mm or less. As a result, in the serpentine heat exchanger having the above-described dimensions, an optimal corrugated fin can be set.

The corrugated fin comprises a vent portion in contact with the tube element, a vent portion in contact with one tube element, and a flat portion located between the vent portions in contact with the other tube element. In the part, a plurality of louvers extending in a direction perpendicular to the ventilation direction are formed in order in the ventilation direction, and the inclination angle of the louver with respect to the ventilation direction is set to approximately 24 ° or more and 40 ° or less. Is desirable. As a result, a corrugated fin having an optimum louver can be obtained.

Further, in the serpentine heat exchanger, it is preferable that a distance between an end of the louver and the tube element is within a range of about 0.2 mm or more and 1.5 mm or less. It is desirable that the thickness be approximately 1.6 mm or more and 3.9 mm or less. Thereby, the drainage property of the corrugated fin can be improved.

Further, the serpentine heat exchanger is disposed substantially at the center in the laminating direction, and has one inlet-side header pipe communicating with the refrigerant inlet portion extending downstream in the ventilation direction, and is disposed at both ends in the laminating direction. And a pair of outlet header pipes communicating with a refrigerant outlet portion extending upstream in the ventilation direction, wherein the serpentine tube communicates with one of the inlet header pipe and one of the outlet header pipes. It may be constituted by one serpentine tube and a second serpentine tube communicating with the other of the inlet side header pipe. Thereby, the passage resistance of the serpentine tube can be reduced and the distribution of the refrigerant can be improved, so that the heat exchanger performance can be improved.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

The serpentine heat exchanger 1 shown in FIGS. 1 and 2 has an inflow header connected to one side and communicating with a refrigerant inflow pipe 3 extending downstream in a ventilation direction (shown in FIG. 2). A pipe 2, an outflow header pipe 4, which is disposed on the other side and communicates with a refrigerant outflow pipe 5 extending upstream in the ventilation direction, and a communication between the inflow header pipe 2 and the outflow header pipe 4. Also, a plurality of folded portions 6A located on one side and the other side and a folded portion 6A on one side
And a plurality of folded refrigerant passages 6B communicating with the folded portion 6A on the other side, and corrugated fins disposed between each of the folded refrigerant passages 6B adjacent to the serpentine tube 6. 7 at least. In this embodiment, a pair of end plates 8 are provided at both ends of the folded refrigerant passage 6B and the corrugated fin 7 in the stacking direction.
A corrugated fin 7 is also provided between the folded refrigerant passage 6B and each of the front end plates 8 and 9. The serpentine tube 6 is made of Z
It is desirable to form with an n thermal spray tube or a Zn thermal spray tube + a high corrosion resistant tube.

The serpentine heat exchanger 1 having the above structure
In the above, a factor indicating the cooling performance (cooling capacity) and a factor indicating the ventilation resistance are obtained by an experiment, and a factor (heat exchanger capacity) Fa (F) indicating the overall capacity of the heat exchanger is obtained from these factors.
a = cooling capacity / ventilation resistance). The heat exchanger capacity Fa is proportional to the cooling capacity and inversely proportional to the ventilation resistance. The refrigerating capacity / ventilation resistance was determined by experiment as a factor Fa indicating the heat exchanger capacity, and as a result, a characteristic diagram shown in FIG. 3 was obtained. As a result, a width Cwm of 50 mm in the ventilation direction is obtained as a point having the maximum heat exchanger capacity, and assuming that the maximum heat exchanger capacity is 100%, a range having a heat exchanger capacity of 80% or more in the Fa wind direction is obtained. Width Cw approximately 35
The range of not less than mm and not more than 65 mm was obtained.

The corrugated fins 7 are shown in FIGS.
As shown in FIG. 7, the vent portion 11a which is brought into contact with one of the folded refrigerant passages 6B adjacent to the serpentine tube 6 is joined.
And a flat portion 12 connecting the bent portion 11a and the other bent portion 11b. The bent portion 11b is in contact with the other folded refrigerant passage 6B, and corresponds to the space between the adjacent folded refrigerant passages 6B. It has a predetermined fin height Fh and a fin pitch Fp between the vertices of the vent portion 11a which is in contact with and joined to the one folded refrigerant passage 6B.

The fin height Fh corresponds to the width between the adjacent folded refrigerant passages 6B of the serpentine tube 6, and in order to reduce the dimension of the folded refrigerant passage 6B and the corrugated fin 7 in the laminating direction, the fin height Fh is required. It is desirable to reduce the height Fh, but there is a problem in that reducing the fin height Fh increases ventilation resistance. For this reason, when the relationship between the fin height Fh and the heat exchanger capacity Fa is obtained by experiment, and the optimum fin height is obtained,
The characteristic diagram shown in FIG. 7 is obtained, and the fin height F at the maximum capacity is obtained.
9 mm was obtained as hm. And heat exchanger capacity F
Assuming that the range where a is 80% or more of the maximum is a proper range Fhs of the fin height Fh, the proper range Fhs is obtained in a range of approximately 5.0 mm or more and 13 mm or less. Then, it is necessary to form a width between the adjacent folded refrigerant passages 6B according to the fin height Fh, and the vent portions 6A and 6B are bent so as to have this width.

Further, in order to reduce the dimension in the laminating direction, it is necessary to reduce the fin height Fh and the height Th of the serpentine tube 6, but if the fin height Fh is reduced, the flow path resistance of the refrigerant increases. Therefore, the most appropriate balance between the two is required. In this range, the tube height Th is approximately 1.6 m.
It is desirable that the distance be in the range of not less than m and not more than 3.9 mm.

FIG. 8 shows the relationship between the fin pitch Fp and the heat exchanger capacity Fa obtained by experiments in the serpentine heat exchanger 1 in which the width Cw in the ventilation direction is set to 50 mm. It is a characteristic diagram,
It can be seen that the maximum capacity is obtained when the fin pitch Fp is 3.9 mm. Assuming that the range in which the heat exchanger capacity Fa is 80% or more of the maximum is the appropriate range Fps of the fin pitch Fp, as in the case described above, the appropriate range Fps
Is approximately 2.8 mm or more and 5.0 mm or less from the characteristic diagram shown in FIG.

The corrugated fin 7 has a louver 10 which extends perpendicularly to the ventilation direction and is formed by cutting and raising a plurality of pieces in the ventilation direction. As a result, air passing along the corrugated fins 7 is
Therefore, the heat exchange efficiency of the corrugated fins 7 can be improved since the corrugated fins 7 can pass through the corrugated fins 7 in such a manner as to intersect. However,
The heat exchange capacity can be increased by increasing the inclination angle (louver angle) Ra of the louver with respect to the flat portion 12 of the corrugated fin 7, but on the other hand, increasing the louver angle Ra increases the ventilation resistance, thereby increasing heat. Since the exchange capacity is reduced, there is an optimum louver angle Ra.

Therefore, in the serpentine-type heat exchanger 1 having the above-described configuration, an experiment was performed by changing the louver angle Ra, and the heat exchanger capacity Fa was obtained. The relationship between the louver angle Ra and the heat exchanger capacity Fa was determined. As a result, a characteristic diagram shown in FIG. 9 was obtained. Then, 32 ° is obtained as the louver angle Ram at the time of the maximum capacity, and assuming that the maximum capacity is 100%, an appropriate louver angle range Ras of 80% or more is obtained. Range was obtained.

The thickness of the fin plate Ft is preferably as thin as possible in view of cost. However, in order to increase the fin strength, the fin plate thickness needs to be more than a predetermined value. It is desirable to set it in the range of not less than 06 mm and not more than 0.15 mm. Further, the end of the louver 10 formed on the corrugated fin 7 and the fin vent 1
The distance Dr between the vertices of 1a and 11b is approximately 0.2 mm
It is desirable to set it to 1.5 mm or less. The distance D
By setting r in this range, the drainage of the fins can be improved and the fin strength when the fins are formed in a corrugated shape can be maintained. Further, the joining property by brazing between the corrugated fin 7 and the serpentine tube 6 can be improved.

A serpentine type heat exchanger 20 shown in FIGS. 10 to 12 has a louver group 10A comprising a plurality of louvers.
A plurality of corrugated fins 7, one inflow-side header pipe 21 disposed at one end of the corrugated fin 7 at a substantially central position in the laminating direction, and a pair of outflows disposed at the other end of both ends in the laminating direction. A first serpentine tube 25 which communicates the side header pipes 22 and 23 with the inflow side header pipe 21 and one of the outflow side header pipes 22 and folds between the one end and the other end a plurality of stages; Side header pipe 21 and the other outflow side header pipe 2
3 and a second serpentine tube 26 that is folded back between the one end and the other end by a plurality of steps.

The first serpentine tube 25 includes a folded portion 25A and a folded refrigerant passage 25B extending between the folded portions 25A. Similarly, the second serpentine tube 26 also has a folded portion 26A. And a folded refrigerant passage 26B extending between the folded portions 26A. Further, the inlet-side header pipe 21
Communicates with the refrigerant inlet 28 through an extension pipe 27 that extends and bends downstream of the serpentine heat exchanger 20 in the ventilation direction, and extends from an expansion valve or the like located upstream of the refrigeration cycle, for example. It is connected to a pipe (not shown). Further, the outlet header pipes 22, 23 are
A pair of extension pipes 2 extending and bending to the upstream side in the ventilation direction
The refrigerant is communicated with the refrigerant outlet 31 via 9, 30 and connected to an accumulator or an internal heat exchanger located downstream of the refrigeration cycle via a pipe (not shown).

In this embodiment, the first and second
Since the two serpentine tubes 25 and 26 form two refrigerant flow paths that flow in parallel from the inlet header pipe 21 to the outlet header pipes 22 and 23, the flow resistance of the refrigerant can be reduced. Therefore, since the width of the serpentine tubes 25 and 26 can be reduced, the width of the serpentine heat exchanger in the stacking direction can be further reduced. Therefore, in this embodiment, two parallel refrigerant flow paths are formed, but a plurality of refrigerant flow paths may be formed as necessary. Note that the dimensions of each element described above are also effective in the serpentine heat exchanger according to this embodiment.

[0025]

As described above, according to the present invention, in the serpentine heat exchanger, the heat exchange capacity and the ventilation resistance of the heat exchanger are obtained by experiments, and the heat exchanger capacity (heat exchange capacity) is obtained from these. / Ventilation resistance), and the dimensions of each element of the serpentine heat exchanger are set within a range where this value is equal to or greater than a predetermined value. Therefore, the heat exchanger is downsized while maintaining the performance of the heat exchanger. Therefore, the size of the vehicle air conditioner on which the heat exchanger is mounted can be reduced, and further, the size of the vehicle can be reduced, the interior space of the vehicle can be ensured, and the like.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration of a serpentine heat exchanger according to a first embodiment of the present invention.

FIG. 2 is a side view of the serpentine heat exchanger shown in FIG.

FIG. 3 shows the width Cw of the heat exchanger in the ventilation direction and the capacity F of the heat exchanger.
FIG. 4 is a characteristic diagram showing the relationship of a.

4A is a side view showing a configuration of a corrugated fin, and FIG. 4B is a cross-sectional view thereof.

FIG. 5 is a partially enlarged sectional view of a corrugated fin.

FIG. 6 is an explanatory view showing an attached state and a side view of a corrugated fin.

FIG. 7 is a characteristic diagram showing a relationship between a fin height Fh of a corrugated fin and a heat exchanger capacity Fa.

FIG. 8 is a characteristic diagram showing a relationship between a fin pitch Fp of a corrugated fin and a heat exchanger capacity Fa.

FIG. 9 is a characteristic diagram showing a relationship between a louver angle Ra of a corrugated fin and a heat exchanger capacity Fa.

FIG. 10 is a front view showing a serpentine heat exchanger according to a second embodiment of the present invention.

FIG. 11 is a bottom view of the serpentine heat exchanger according to the second embodiment.

FIG. 12 is a side view of a serpentine heat exchanger according to a second embodiment.

[Explanation of symbols]

 1,20 Serpentine heat exchanger 2,21 Inlet header pipe 4,22,23 Outlet header pipe 6,25,26 Serpentine tube 7 Corrugated fin 8,9 End plate 10 Louver

Claims (7)

[Claims] An inlet header pipe through which a refrigerant flows;
An outlet header pipe from which the refrigerant flows out, at least one serpentine tube that is folded back at a predetermined interval and communicates between the inlet header pipe and the outlet header pipe, and is formed by the serpentine tube. A corrugated fin disposed at least between a plurality of folded refrigerant passages, wherein the width of the heat exchanger in the ventilation direction of the air flowing through the corrugated fin is approximately 35 mm or more and 65 mm or less. And the fin height of the corrugated fin is approximately 5 mm or more.
mm. The serpentine heat exchanger is formed within the range of not more than mm, and the interval between the folded refrigerant passages of the serpentine tube is formed corresponding to the fin height. 2. In each of said corrugated fins,
2. A fin pitch between a bent portion in contact with one tube element and a next bent portion in contact with one tube element is approximately 2.8 mm or more and 5.0 mm or less. The serpentine heat exchanger as described. 3. The plate thickness of the corrugated fin is set to approximately 0.
The serpentine heat exchanger according to claim 1, wherein the heat exchanger has a diameter of from 0.6 mm to 0.15 mm. 4. The flat plate according to claim 1, wherein the corrugated fin comprises a vent portion in contact with the tube element, a vent portion in contact with one tube element, and a flat portion located between the vent portions in contact with the other tube element. In the section, a plurality of louvers extending in a direction perpendicular to the ventilation direction are formed in order in the ventilation direction, and the inclination angle of the louver with respect to the ventilation direction is set to approximately 24 ° or more.
The serpentine heat exchanger according to claim 1, 2 or 3, wherein the angle is 0 ° or less. 5. The serpentine heat exchanger according to claim 4, wherein the distance between the end of the louver and the tube element is within a range of approximately 0.2 mm or more and 1.5 mm or less. . 6. The thickness of the serpentine tube is as follows:
The serpentine heat exchanger according to any one of claims 1 to 5, wherein the length is approximately 1.6 mm or more and 3.9 mm or less. 7. The serpentine heat exchanger includes one inlet-side header pipe arranged substantially at the center in the stacking direction and a pair of outlet-side header pipes arranged at both ends in the stacking direction. The tube is constituted by a first serpentine tube communicating with one of the inlet header pipe and the outlet header pipe, and a second serpentine tube communicating with the other of the inlet header pipe. The serpentine heat exchanger according to any one of claims 1 to 6, characterized in that: