JPH01181092A - Heat exchanger - Google Patents

Abstract

PURPOSE:To improve connecting strength between tubes and corrugate fins and prevent the destruction of the tubes, by a method wherein the width of a corrugate fin is made larger than that of a tube and recesses or notches are formed on the crest of the corrugate fin while the recess or notches are fitted to the tubes to contact corrugate fins with the whole periphery of the tubes substantially. CONSTITUTION:A tube 4, having a thickness (x) and a width (y), is made of brass, for example, and plated with a soldering material 6 on the surface; the tube 4 is constituted of U-shape parts 41, 42 and flat parts 43, 44 which contact with corrugate fins 5 and a hot-water passage 45 is formed in the tube 4. The corrugate fin 5 is made of brass and is provided with a width larger than that of the tube 4 while recesses 53, 54 having the thickness of about x/2 and the width of (y) are formed at the crests 51, 52 of the fin to fit the recesses 53, 54 to the tube 4 so as to contact the fins along the whole periphery of the tube 4 substantially. The recesses 53, 54 function as reinforcing parts for restricting the deformation of the tube 4 due to the fluctuation of the inner pressure of the tube 4. Soldering fillet parts 61, 62 are formed on connecting parts (a), (b) between the tube 4 and the corrugate fin 5 by the soldering material 6, for example.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat exchanger mounted on an automobile, and particularly to a heat exchanger used as a heater core of a hot water heating system for an automobile.

[Prior Art] Conventionally, as shown in FIGS. 8 and 9, the core portions 110 of the heater core of this type of automatic Φ-circular hot water heating device are arranged in parallel from one side to the other, and the inner A large number of flat tubes 120 through which hot water flows, and each tube 12
The corrugated fins 130 are stacked one on top of the other.

Conventionally, the method for manufacturing corrugated fins 130 is as follows:
A brass plate cut to a length similar to the thickness of the core part 110 is passed between two gear-shaped forming rollers (none of which are shown) in a corrugated fin forming machine, and these forming rollers rotate. By doing so, it is processed into a corrugated (waveform) shape as shown in FIG. 10 (hereinafter referred to as roller processing).

Further, at the joint between the tube 120 and the peak portion 131 of the corrugated fin 130, a solder joint (hereinafter referred to as a solder fillet) 140 is formed using a solder material.

[Problems to be Solved by the Invention] However, in general, in the core portion 110 of the heater core, when hot water passes through the tube 120, high pressure is generated inside the tube 120 due to pressure fluctuations of a hot water pump (not shown). It may be added.

Therefore, a large stress is generated outward from the inside of the tube 120, and cracks are generated in the solder fillet portion 140 around the tube 120, and the cracks gradually progress. As a result, separation between the tube 120 and the corrugated fin 120 progresses, so the tip 1-
The deformation of 7120 gradually increases, and eventually the 0-shaped portion 121 of the tube 120 is pulled by the flat portion 122 and breaks.

Therefore, hot water leaks from the tube 120,
There was a risk that the core portion 110 of the heater core would deteriorate in function or become inoperable.

Here, in Utility Model Application Publication No. 58-154381,
A heat exchanger is shown in which corrugated fins are installed so that adjacent tubes are not connected to each other so that the deformation of the tubes does not affect the adjacent tubes.

Further, Japanese Utility Model Application Publication No. 48-57761 discloses a heat exchanger in which corrugated fins are arranged between staggered tubes and extend around one of the tubes.

However, since the former cannot prevent the tube from deforming, there is a risk of it breaking if a large stress is generated inside the tube, and the latter has the possibility of breaking when a large stress is generated inside the tube. However, there is a risk that the above-mentioned problem may be destroyed.

An object of the present invention is to provide a heat exchanger that improves the bonding strength between tubes and corrugated fins and prevents the tubes from breaking.

[Means for Solving the Problems] The heat exchanger of the present invention has corrugated fins bent in a wave-like manner between a large number of flat tubes arranged in parallel from one side to the other and through which a fluid to be heat exchanged flows. In the heat exchanger, the corrugated fins have a width larger than that of the tube, and the corrugated fins have a width larger than that of the tube, and the corrugated fins have peaks joined to the flat side surfaces of the tubes by brazing. A configuration is adopted in which a recess or notch corresponding to the thickness and width of the tube is formed, and the recess or notch is fitted into the tube so that the corrugated fin comes into contact with the tube over almost the entire circumference. did.

[Function] The heat exchanger of the present invention has the following function due to the above structure.

The width of the corrugated fin is made larger than the width of the tube, and a recess or notch corresponding to the thickness and width of the tube is formed in the crest of the full gate fin. The recesses or notches of the corrugated fins are fitted into the tube, and the full gate fins are brought into contact with the tube over almost its entire circumference. For this reason, the contact area between the tube and the corrugated fin is larger than that of conventional ones, making it possible to reinforce the tube.
Even if a large stress is generated outward from the inside of the tube, deformation of the tube can be suppressed.

Accordingly, the area where the corrugated fin and the tube are joined by brazing becomes larger, and the brazing material also wraps around the tube sufficiently, improving the joint strength of the area where they are joined.

Furthermore, since the contact area between the tube and the corrugated fins is increased, heat transfer from the tube to the corrugated fins is improved.

[Effects of the Invention] The heat exchanger of the present invention has the following effects due to the above structure and operation.

By reinforcing the tube and suppressing deformation of the tube, cracking and destruction of the tube can be prevented. Therefore, leakage of the fluid to be heat exchanged from the tubes can be prevented, and there is no risk of functional deterioration or failure, and the reliability of the heat exchanger can be improved.

[Embodiment] An embodiment of the heat exchanger of the present invention will be explained based on FIGS. 1 to 7.

1 and 2 show a core portion of a heater core of a hot water type heating system for an automobile employing a first embodiment of the present invention, and FIG. 3 shows the heater core thereof.

1 shows a heater core of a hot water heating system for an automobile. The heater core 1 is provided with a core part 2 having a plurality of tube rows and at both ends 21 and 22 of the core part 2. It consists of an F side tank 3A and a lower side tank 3B. Upper tank 3A
The lower tank 3B includes a substrate 31 into which the upper end of the tube 4 is inserted, and a lid plate 32 joined to the substrate 31. Of these, the lid plate 32 of the upper tank 3A is formed with an inlet vibe 33 and an outlet vibe 34 that are connected to hot water piping (not shown).

The core portion 2 includes a large number of flat tubes 4 arranged in parallel from one side to the other, and corrugated fins 5 joined between each tube 4 by soldering.

The tube 4 is made of brass and has a thickness χ and a width y, and has a solder material 6 plated on its surface. The tube 4 includes a zero-shaped portion 41.42 that contacts the full gate fin 5 and a flat portion 43.44, which is a flat side surface, and has a hot water passage 45 formed therein through which hot water, which is a fluid to be heat exchanged, flows.

The corrugated fin 5 is made of brass and has a width larger than the width of the tube 4. The corrugated fin 5 is made of brass and has a width larger than that of the tube 4.
1 and the peak portion 52 on the right side in the figure are provided alternately. These peaks 51 and 52 have a thickness of approximately χ/2 of the tube 4.
, width y are integrally formed during roller machining, and the recesses 53,54 are fitted into the tube 4 so as to be in contact with the tube 4 over almost its entire circumference. These recesses 53 and 54 function as reinforcing portions that suppress deformation due to pressure fluctuations inside the tube 4. The concave portion 53 of the mountain portion 51 is in contact with the left half of the 0-shaped portion 41, 42 of the tube 4 and the flat portion 43 in the drawing. Recessed portion 5 of mountain portion 52
4 is in contact with the right half of the 0-shaped portion 41, 42 of the tube 4 and the flat portion 44 in the drawing.

In addition, a joint a between the tube 4 and the full gate fin 5,
For example, a solder fillet portion 6 is formed in b by the solder material 6.
1.62 is formed.

The operation of the heater core 1 of this embodiment will be explained based on the drawings.

As shown in FIG. 4, the corrugated fin 5 of this embodiment is constructed by inserting a brass plate 50 having a width larger than the width of two rows of tubes 4 into two forming rollers t1 in a corrugate fin forming machine 7.
72 convex portions 71a, 72a and concave portions 71b, 72b.
72 rotates, recesses 53.5 having the same number of rows as the number of rows of tubes 4 are formed in the peaks 51.52 as shown in FIG.
Wave-shaped corrugated fin 5 with 4 formed in a predetermined position
to form. Concave portions 53 and 54 of this full gate fin 5
The recesses 53 and 54 are fitted into the tube 4 so that they contact the tube 4 over almost its entire circumference.

The corrugated fins 5 and the tubes 4 are alternately stacked to form the core part 2, and a core holding jig (not shown) is used.
After the tube 4 and the corrugated fins 5 are fixed so as not to fall off, both ends of the tube 4 are inserted into holes (not shown) in the substrate 31 of the tank 3.

Furthermore, since the surface of the tube 4 is plated with solder material 6, when this core portion 2 passes through a high-temperature furnace, this solder material 6 will melt, causing the tube 4 to melt.
and the corrugated fin 5 are joined. In other words, the left half of the 0-shaped portion 41, 42 of the tube 4 and the flat portion 43
and the concave portion 53 of the peak portion 51 of the corrugated fin 5 are joined, and the right half of the 0-shaped portion 41.42 of the tube 4 and the flat portion 44 are joined to the concave portion 53 of the peak portion 51.

Further, the substrate 31 is also joined to the tube 4. At this time,
S solder fillet portions 61 and 62 are formed at the joints a and b between the tube 4 and the corrugated fin 5.

Here, the tube 120 of the core part 110 and the corrugated fin 1 of the conventional heater core shown in FIGS.
30 is the peak part 13 of the full gate fin 130.
1 is in line contact with the flat portion 122 of the tube 120, the solder fillet portion 140 is formed only on the flat portion 122 of the tube 120, and cracks are most likely to occur in the tube 120 (stress is greatest in the tube 120). (G) The structure was such that the zero-shaped portion 121 could not be reinforced by the corrugated fins 130 and the solder fillet portions 140.

With respect to the core portion 110 of such a conventional heater core,
In this embodiment, a concave portion 53.54 having a thickness χ/2 and a width y of the tube 4 is formed in the peak portion 51.52 of the corrugated fin 5, so that the tube 4 is connected to both corrugated fins 51.52.
The character 1 part 41.42 of the tube is reinforced in the wrapped state, and the solder fillet part 61.62 is also formed in the character 1 part 41.42 of this tube, reinforcing the character 1 part 41.42 of the tube 4. It has the effect of being able to do the following.

In addition, the core portion 110 of the conventional heater core has a tube 1
Since the contact between 20 and the corrugated fin 130 was a line contact, the bonding area of the solder fillet 140 was small;
There was a problem that the joint strength between the tube 12G and the corrugated fin 130 was low.

With respect to the core portion 110 of such a conventional heater core,
In this embodiment, since the concave portion 53.54 of the peak portion 51.52 of the corrugated fin 5 and the single-shaped portion 41.42 and flat portion 43.44 of the tube 4 are in surface contact, the solder fillet 61.62 This has the effect of increasing the bonding area and increasing the bonding strength between the tube 4 and the corrugated fins 5.

Therefore, in this embodiment, the concave portions 53.54 of the peak portions 51.52 of the corrugated fins 5 and the solder fillet portions 6
1.62, it is possible to reinforce not only one side of the 1-shaped portion 41.42 of the tube 4, but also both sides of the U-shaped portion 41.42 of the tube 4, and to increase the bonding strength between the tube 4 and the corrugated fin 5. can be dramatically improved compared to conventional heat exchangers.

Therefore, when hot water passes through the hot water passage 45 of the tube 4, high pressure is applied inside the tube 4 due to pressure fluctuations of the hot water pump (not shown), and the pressure increases from the inside of the tube 4 toward the outside. Even when stress is generated, the deformation of the tube 4 can be suppressed, and the generation of cracks and destruction at the single-shaped portions 41 and 42 where the stress is the greatest in the tube 4 can be prevented.

Therefore, leakage of hot water from the tube 4 can be prevented, a decrease in the cooling efficiency of the hot water in the heater core 1 or a failure state can be prevented, and the reliability of the heater core 1 can be improved.

6 and 7 show the core portion 2 of a heater core employing a second embodiment of the heat exchanger of the present invention.

(The same functional objects as in the first embodiment are given the same numbers.) The corrugated fin 8 of this embodiment is provided with alternating peaks 81 on the left side in the figure and peaks 82 on the right side in the figure. These peaks 8
A notch 83.84 having a thickness of approximately χ/2 and a width y is formed in the tube 4 at 1.82, and serves as a reinforcing portion to suppress deformation due to pressure fluctuations inside the tube 4. This mountain part 8
The notch 83 of 1 is in contact with the left half of the 1-shaped portion 41 , 42 of the tube 4 and the flat portion 43 . Yamabe 82
The notch 84 is in contact with the right half of the 1-shaped portion 41 , 42 of the tube 4 and the flat portion 44 .

Solder fillet portions 61, 62, 63, 64 are formed on both sides of the corrugated fin 8 at the joint a1b between the tube 4 and the corrugated fin 5 by the above-mentioned notches 83.84.

Therefore, in this embodiment, the solder fillet portions 63 and 64 are increased compared to the first embodiment, and the bonding strength between the tube 4 and the corrugated fin 5 can be further increased compared to the first embodiment. be.

[Other Examples] In this example, the heat exchanger of the present invention was used in the heater core of a dry-water heating system for an automobile, but it may also be used in a heater core of a hot-water heating system for other vehicles or ships.
It may also be used in radiators of engines of vehicles, ships, etc.

In this example, soldering was used to braze the tube and corrugated fin, but hard brazing may also be used.
Brazing may be performed in a vacuum or in a neutral or reducing atmosphere.

In this example, recesses or notches were provided in the peaks on both sides of the corrugated fin, and the four parts or notches were brought into contact with the tube, but the peaks of at least one corrugate fin corresponded to the thickness and width of the tube. A recess or cutout may be provided and the recess or cutout may be brought into contact with the tube.

Alternatively, a recess or a notch may be provided only in the outermost tube of the heater core 1 and the crest of the corrugated fin that contacts the tube, and the recess or notch may be brought into contact with the tube.

In this embodiment, the tanks are provided at both ends of the core portion, but the tanks may be provided only at one end. Further, various joining methods such as welding, fixing by caulking, etc. can be used to join the tank substrate and the lid plate, and to join the substrate and the tube.

[Brief explanation of the drawing]

1 and 2 are enlarged views of the main parts of the core of a heater core for a 5A hot water heater for an automobile employing the first embodiment of the heat exchanger of the present invention, and FIG. 3 shows the heater core of FIG. 1. 4 is a schematic view showing a corrugated fin forming machine for manufacturing the corrugated fin shown in FIG. 1, FIG. 5 is a perspective view showing the corrugated fin of the heater core shown in FIG. 1, and FIG. FIG. 7 is a perspective view showing the corrugated fins of the heater core of FIG. 6, and FIGS. 8 and 9 are views of the conventional heater core. FIG. 10, which is an enlarged view of the main part of the core part, is a perspective view showing corrugated fins of a conventional heater core. In the diagram

Claims (1)

[Claims] 1) Corrugated fins bent in a wave-like manner are arranged between a large number of flat tubes arranged in parallel from one side to the other, through which a fluid to be heat exchanged flows, and the crests of the corrugated fins are In the heat exchanger formed by joining the flat side surface of the tube by brazing, the width of the corrugated fin is made larger than the width of the tube, and the crest of the corrugated fin has a shape corresponding to the thickness and width of the tube. A heat exchanger characterized in that a recess or notch is formed and the recess or notch is fitted into the tube so that the corrugated fin comes into contact with the tube over substantially the entire circumference.