JP3769085B2 - Heat exchanger and method for manufacturing heat exchanger fins - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat exchanger that is used in an air conditioner or a refrigerator and that transfers heat between fluids such as air and a refrigerant.
[0002]
[Prior art]
FIG. 6 is a plan view of fins of a conventional heat exchanger disclosed in, for example, Japanese Patent Application Laid-Open No. 8-54194. 1 is a fin, and 2 is a heat transfer tube insertion hole formed in the fin 1. Reference numeral 3 denotes a perforated cut portion cut intermittently between rows of fins 1.
[0003]
FIG. 7 is a perspective view of the heat exchanger 4 using the fins 1, 5 is a heat transfer tube which is inserted into and closely attached to the heat transfer tube insertion hole 2, and the refrigerant inlet is 5a, the refrigerant outlet is 5c, and the middle is 5b. And
[0004]
About the heat exchanger 4 comprised as mentioned above, the effect | action at the time of being used as a condenser is demonstrated, referring drawings.
[0005]
The high-temperature refrigerant that has flowed into the heat transfer tube 5a flows out as a low-temperature refrigerant from the heat transfer tube 5c through the heat exchanger tube 5b while releasing heat to the air flowing on the surface of the fin 1.
[0006]
Here, the refrigerant flowing in the heat transfer tube 5 has a large temperature difference between the inlet and the outlet, and generally there is often a difference of 30 ° C. or more. Therefore, by preventing heat conduction between the heat transfer tubes 5 having different temperatures, the degree of supercooling of the refrigerant can be increased, and the aim is to increase the amount of heat exchange, and in order to enable easy manufacturing in the manufacturing process, A cut portion 3 is formed by intermittently cutting at a predetermined pitch in the form of perforations.
[0007]
Next, the manufacturing method of the fin 1 is demonstrated using FIG. While processing the heat transfer tube insertion holes 2 at a predetermined row pitch RP and step pitch HP, the steel tube is fed at a pitch twice that of RP and cut between rows using upper and lower cutting blades 6 having a length shorter than RP × 2. Part 3 is processed. Therefore, in order to continuously process the heat transfer tube insertion hole 2 and the cutting part 3, two stages of heat transfer tube insertion hole processing dies are provided.
[0008]
[Problems to be solved by the invention]
However, since many portions of the conventional heat exchanger 4 that are not cut remain between the rows, the heat conduction is not completely cut off, and the decrease in the heat exchange amount due to the heat conduction cannot be sufficiently suppressed. Moreover, if the length of the cutting part 3 is made sufficiently long, not only the strength of the fin 1 is lowered, but also a large mold must be manufactured according to the progressive pitch of the molding mold of the fin 1.
[0009]
On the other hand, if the space between the rows is completely cut, the number of parts of the fin 1 is increased, and there is a problem that the number of man-hours is increased in the handling.
[0010]
The object of the present invention is to cut the intermittent cutting portions 3 between the rows of fins 1 efficiently without reducing the strength of the fins 1 without investing in the mold.
[0011]
[Means for Solving the Invention]
In order to solve the above problems, the heat exchanger of the present invention has a long cut portion only in the vicinity of the heat transfer tube at the relatively high temperature refrigerant inlet and the heat transfer tube at the relatively low temperature refrigerant outlet without completely cutting the fins. It is comprised so that it may have.
[0012]
As a result, the heat conduction between the heat transfer tubes having a large temperature can be effectively cut off, and the amount of heat exchange can be increased.
[0013]
In addition, the heat exchanger fin manufacturing method of the present invention is provided with a cutting blade having a length smaller than the maximum progressive pitch in the row to be intermittently cut, and the progressive pitch is an integer multiple of the step pitch. In part, by sequentially feeding at a pitch that is an integer multiple less than the others, partly longer cut parts are obtained.
[0014]
This makes it possible to obtain a long cut part in part with a relatively small mold and cutting blade in the manufacturing process, and it is not necessary to invest in the mold to obtain a long cut part. Then, since it is a comparatively short cut portion, the strength of the fin is hardly lowered.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The invention according to claim 1 of the present invention includes a plurality of rows in which refrigerant flows inside and heat transfer tubes arranged in a plurality of stages, and a plurality of fins in which the heat transfer tubes are inserted and air flows between them. In the heat exchanger in which the refrigerant inlet and the refrigerant outlet are arranged in different rows at substantially the same height, and the heat transfer tubes are connected to each other to form a refrigerant flow path of at least one circuit, Is provided with intermittent cutting parts, and the cutting part is longer than the other parts in the vicinity of the refrigerant inlet or outlet. By preventing conduction, the heat conduction is effectively cut off without reducing the strength of the fin.
[0016]
The invention according to claim 2 is performed by sequentially forming the heat transfer tube insertion holes at a predetermined row pitch and step pitch on the thin plate-like metal fin material, and intermittently cutting the rows cut in the entire region. In press working to form heat exchanger fins in multiple rows, a cutting blade with a length smaller than the maximum progressive pitch is provided in the row to be cut intermittently, and the progressive pitch is an integer multiple of the step pitch. However, it is possible to obtain a cutting part that is partly longer than the other and longer than the cutting blade by partly feeding at an integer multiple pitch that is smaller than the others, and with one type of cutting blade, it is uneven and long cutting The part can be easily manufactured. That is, a long cutting part can be obtained partially with a relatively small mold and cutting blade in the manufacturing process.
[0017]
【Example】
Embodiments of the present invention will be described below with reference to FIGS.
[0018]
FIG. 1 is a plan view of fins of a heat exchanger according to an embodiment of the present invention. FIG. 2 is a perspective view of the heat exchanger 14 according to an embodiment of the present invention. In FIGS. 1 and 2, 11 is a fin, and 12 is a heat transfer tube insertion hole formed in the fin 11. Reference numeral 15 denotes a heat transfer tube which is inserted into and closely attached to the heat transfer tube insertion hole 12, and the refrigerant inlet is 15a, the refrigerant outlet is 15c, and the middle is 15b. Reference numeral 13 denotes a perforated cut portion cut intermittently between the rows of fins 11. In the vicinity of the refrigerant inlet heat transfer tube 15a and the refrigerant outlet heat transfer tube 15c, the cutting portion 13 forms a cutting portion 13a that is longer than the other portions.
[0019]
Next, the effect | action in one Example at the time of using the heat exchanger 4 of this invention as a condenser is demonstrated using drawing.
[0020]
A high-temperature superheated gas refrigerant flows in from the heat transfer tube 15a, and flows out as a supercooled liquid refrigerant from the heat transfer tube 15c through the heat transfer tube 15b. During this time, the refrigerant cools and condenses while releasing heat to the air flowing between the fins 11. At the same time, heat conduction occurs from the heat transfer tube 15a through which the high-temperature gas refrigerant flows through the fin 11 to the heat transfer tube 15c through which the low-temperature liquid refrigerant flows. However, since the fin is provided with a long cut portion between the rows of the heat transfer tubes 15a and 15c, heating of the low-temperature refrigerant by heat conduction hardly occurs, so that the refrigerant can be largely cooled and the heat exchange amount is increased. .
[0021]
Moreover, since the cutting part is provided intermittently and the cutting part 13 is relatively short except in the vicinity of the heat transfer tubes 12a and 12c, not only the number of fin parts does not increase, but also the fin strength decreases. There is nothing.
[0022]
FIG. 3 shows a heat exchanger 24 according to another embodiment of the present invention. In this case as well, the fins 21 are provided with cutting portions 23 to transfer heat in the vicinity of the refrigerant inlet heat transfer tube 22a and the refrigerant outlet heat transfer tube 22c. It can be similarly implemented by providing an intermittent cutting portion 23a that is longer than the vicinity of the heat tube 22b.
[0023]
FIG. 4 shows the fins 21 of the heat exchanger of FIG. FIG. 5 is a perspective view of a main part when the cutting part 23 of the fin 21 is processed. In FIG. 4, intermittent cut portions 23 are formed between the rows of the heat transfer tube insertion holes 25 and the heat transfer tube insertion holes 25 in the fin 21. The cut part 23 forms a long cut part 23a, leaving an uncut part at every three times the step pitch of the heat transfer tube insertion hole 25 in part, and 2 parts of the step pitch of the heat transfer tube insertion hole 25 in the other part. An uncut portion is left every double.
[0024]
FIG. 5 is a perspective view of a main part when the cut portion of the heat exchanger fin of this embodiment is processed. Next, the processing method of the cutting part 23 of the fin 21 is demonstrated using FIG. The fin 21 normally processes the heat transfer tube insertion hole 25 (not shown) while progressively feeding the progressive pitch twice the step pitch HP.
[0025]
Next, the upper and lower cutting blades 26 each having a tip smaller than the progressive pitch (HP × 2) are cut while cutting between the rows of the heat transfer tube insertion holes 25 at the center. At this time, the progressive pitch is partially halved to HP × 1. By doing so, the cutting part 23 cut | disconnected by the cutting blade 26 overlaps, and the cutting part 23a longer than another part is formed.
[0026]
When processing the heat transfer tube insertion hole 25 and the cutting portion 23 continuously, even if the progressive pitch is halved, the heat transfer tube insertion hole 25 can only be processed twice at the same position. There is no problem.
[0027]
With this processing method, it is possible to obtain a partially long cutting part at an arbitrary position with a relatively small mold and cutting blade 26, and it is not necessary to invest in the mold to obtain a long cutting part. In addition, since the other portion is a relatively short cut portion, the strength of the fin is hardly lowered, and since it can be continuously manufactured, the man-hour is hardly increased.
[0028]
【The invention's effect】
As described above, according to the present invention, the heat transfer tubes having greatly different temperatures are provided by intermittently providing the cut portions on the inter-row fins and providing a cut portion longer than the other portions in the vicinity of the refrigerant inlet or the refrigerant outlet. It is possible to obtain an advantageous effect that the heat exchange amount can be increased without efficiently interrupting heat conduction between the fins and reducing the strength of the fins or increasing the number of parts.
[0029]
Further, according to the manufacturing process of the present invention, the intermittently cutting row is provided with a cutting blade having a length smaller than the maximum progressive pitch, and the partial pitch is partially set to an integer multiple of the step pitch. Can be obtained by progressively feeding at a smaller integral multiple pitch than the others, and with a relatively small mold and cutting blade, a long cutting part can be obtained partially at any position, and it is also dedicated to obtaining a long cutting part Therefore, the fins are easy to handle in the manufacturing process of the heat exchanger since the strength of the fins is hardly reduced because the other parts are relatively short cut portions. And since it can manufacture continuously, the advantageous effect that man-hours hardly increase is acquired.
[Brief description of the drawings]
FIG. 1 is a plan view of fins of a heat exchanger according to an embodiment of the present invention. FIG. 2 is a perspective view of a heat exchanger according to an embodiment of the present invention. FIG. 4 is a plan view of the fin of the heat exchanger of the same embodiment. FIG. 5 is a perspective view of the main part when processing the cut portion of the fin of the same embodiment. FIG. 6 is a conventional heat exchanger. FIG. 7 is a perspective view of a heat exchanger using a conventional fin. FIG. 8 is a perspective view of a main part when a conventional fin is cut.
11, 21 Fins 12, 22 Heat transfer tube insertion holes 13, 13a, 23, 23a Cutting portions 14, 24 Heat exchanger 25 Heat transfer tube insertion holes 26 Cutting blade

Claims (2)

The heat transfer tubes arranged in a plurality of rows and stages in which the refrigerant flows inside, and a plurality of fins in which the heat transfer tubes are inserted and air flows between them, the refrigerant inlet and the refrigerant outlet are substantially in the same stage. The heat exchangers are arranged in different rows at a height, and the heat transfer tubes are connected to each other to form a refrigerant flow path of at least one circuit, and intermittently cut portions are provided on the fins between the rows, In the vicinity of the refrigerant outlet, the heat exchanger is characterized in that the cutting part is made longer than the other part. The heat transfer tube insertion holes are formed in a thin plate-shaped metal fin material at a predetermined row pitch and step pitch while being progressively fed. In the press processing to form, a cutting blade with a length smaller than the maximum progressive pitch is provided in the row to be cut intermittently, and the progressive pitch is an integer multiple of the step pitch, but partly an integer smaller than the others A method of manufacturing a fin for a heat exchanger, characterized in that, by progressively feeding at a double pitch, a cut part longer than the others is obtained.

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