JPH0798235B2 - Heat exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a heat exchanger and can be used as, for example, a heater or a radiator for an automobile.

[Conventional technology]

Conventionally, tubes used in heat exchangers have been devised in various ways to improve their heat exchange efficiency.

FIG. 6 shows a conventional tube. For example, in the case shown in FIG. 6 (a), a mayer 6 bent in a zigzag shape inside a tube 601 having a flat cross section.
02 is arranged. By arranging the wire 602, the fluid flowing in the tube 601 is agitated.

Alternatively, as shown in FIG. 6 (b), the tube 601
A plurality of ribs 603 extending in the axial direction are projected inward of the tube. This rib 603 also causes the fluid flowing in the tube 601 to be agitated.

Alternatively, as shown in FIG. 6 (c), some tubes 601 may have a plurality of dimples 604 protruding from the outside to the inside.

A corrugated fin having a corrugated shape is joined to the flat side surface of such a flat tube 601. Regular tube to improve the connection with corrugated fins
The flat surface of 601 is shaped like an arc toward the outside, and when the fins are assembled, the flat surface of the tube that is shaped like the bow is elastically deformed inward, which causes the fin and the tube to move. The joining state with 601 is improved.

[Problems to be solved by the invention]

Thus, in order to make the flat side surface of the tube into an arcuate shape outward (hereinafter referred to as a medium convex shape), when molding the tube 601 as a general method, the cross section inside the tube 601 is The most common method is to insert a barrel-shaped core metal and form a tube along the core metal.

However, as shown in FIG. 6, in the case where the wire 602 or the rib 603 and the dimple 604 are arranged and formed over the entire width direction of the tube, when the core metal is arranged, the rib 603 and the like form the core metal. Tube 6 good to get in the way
There is a problem that 01 cannot be molded into a medium convex shape.

[Means for solving problems]

In view of the above problems, it is an object of the present invention to obtain a heat exchanger including a tube having dimples or ribs, which tube is preferably formed into a medium convex shape.

In order to achieve this object, in the present invention, a plurality of protrusions that project toward the inside of the tube are formed on the flat side surface of the tube, and these protrusions are arranged leaving a flat portion of a predetermined width at the center in the width direction of the tube. I tried to blame him.

[Action / effect]

In this way, since the flat portion of a predetermined width is formed in the central portion in the width direction of the tube, the core metal can be brought into contact with the flat side portion of the straight tube without being obstructed by the protrusion. If the tube is formed in conformity with the core metal, it is possible to excellently form the arcuate shape in which the central portion of the flat portion in the width direction is projected outward.

〔Example〕

FIG. 3 is a perspective view when the present invention is used as a heater for an automobile.

Plural flat tubes 102 through which warm water passes are arranged side by side, and corrugated fins 103 bent in a wave shape are joined between the flat tubes 102. An inlet tank 104 is provided at one end of the flat tube 102.
And the outlet tank 105 is joined. An intermediate tank 106 is joined to the other end of the flat tube 102.

An inlet pipe 107 for guiding cooling water into the inlet tank 104 is joined to the inlet tank 104, and an outlet pipe 108 for leading out cooling water in the outlet tank 105 is joined to the outlet tank 105. Has been.

Cooling water having a high temperature flows into the inlet tank 104 through the inlet pipe 107 into the heater 101,
It passes through the inside of the flat tubes 102, which is approximately half the number of tubes 104. Then, it flows into the intermediate tank 106 and further flows from the intermediate tank 106 toward the outlet tank 105 in the flat tube 102. The cooling water that has flowed into the outlet tank 105 is then returned to the engine side through the outlet pipe 108.

In such a cooling water flow, while the cooling water having a high temperature flows through the flat tube 102,
The corrugated fin 103 is heat-exchanged with the air flowing in the direction indicated by the arrow F in FIG. The warm air, which has become high temperature due to this heat exchange, is blown out to the inside of the vehicle compartment.

Next, the flat tube 102 will be described with reference to FIG.

1A is a front view of the tube 102 seen from the flat side, and FIG. 1B is a view of the tube 102 seen from the opening end.
Each shows a state in which a core metal 130 is introduced into the tube 102.

As can be seen from FIG. 1 (a), the flat side surface of the flat tube 102 is left with a flat portion 121 at the center in the width direction, and the dimples 120a are projected on both sides of the flat portion 121 so as to project inward of the tube. It is molded. Dimples 120b are formed on both sides of the flat tube 102 also on the other flat side portions, leaving a flat portion 122 at the center portion in the width direction. This dimple 120a and dimple
120b are arranged alternately with each other in the axial direction of the tube 102.

The flat tube 102 is formed into a tubular shape by bending a strip-shaped plate material, folding the end portion 123, and fixing the end portion 123 by means such as brazing.

The core metal 130 arranged in the flat tube 102 is the first
As shown in FIG. 6B, the central portion has a thick wall thickness, and both end portions have a thin wall shape. That is, the dimples 120 that are inside the tube 102
The core metal of the portion facing a and 120b has its wall thickness reduced by the amount of projection of the dimple, and the surface facing the flat portions 121 and 122 in which the dimples are not formed has a sectional shape perpendicular to the axis of the tube 102. Its wall thickness is made thicker than other parts so that it has a convex shape. Since the strip-shaped plate material of the flat tube 102 is bent along the central thick portion of the core metal 130, as a result, the flat tube is
The center portion of the width direction 102 has an outwardly convex arcuate shape. At this time, the dimples 120a, 1
20b leaves flat portions 121 and 122 in the central portion of the tube 102,
Since the dimples 120a and 120b are arranged on both sides of the core metal 130, the dimples 120a and 120b do not come into contact with the core metal 130 and hinder the molding of the tube 102 into a convex shape.

In the embodiment shown in FIG. 1, the dimples 120a formed on one flat side surface of the flat tube 102 and the dimples 120b formed on the other flat side surface have exactly the same shape. As shown in, the dimples 120b formed on the other flat side surface may be formed to have a larger length in the width direction than the dimples 120a formed on the one flat side surface.

In the embodiment shown in FIG. 1, the length 1 of the flat portions 121 and 122 in the tube width direction is set to about 2 mm or more.
In the illustrated embodiment, the length 1 of the flat portion formed on the other flat side surface is set to about 2 mm or more. Further, in the embodiment shown in FIG. 2, since the flat portion 121 on one flat side surface and the flat portion 122 on the other flat side surface have different lengths in the width direction, the thick portion of the cored bar 130 is adjusted according to the length. The shape is also molded.

Next, a method of molding the tube 102 as described above will be described.

The tube 102 is molded using an apparatus as shown in the schematic view of FIG. First, the strip-shaped plate member 408 is taken out from the metal-like member 407 in which a flat plate-shaped metal is wound in a coil shape, and is passed through the pair of protrusion forming rollers 409 to obtain the strip-shaped plate member 408.
Then, as shown in FIG. 5A, dimples 120a and 120b are formed. Then, after passing through the inside of the first forming roller group 410, the core metal 130 is inserted therein, and the strip plate member 408 is bent to the state shown in FIG. 5B.

Then, in the final step of the first forming roller group 410, FIG.
And then the end portion 123 is wound up by the winding roller compression roller 411, and then the core metal 13 is pressed by the second forming roller group 412.
The final winding is tightened with 0 inserted.

Thereafter, the tube 102 subjected to the final winding process enters the solder bath 415 with the core metal 130 removed, and the outer periphery of the solder is covered with the solder. Next, it is formed in the cooling tank 416, and then finished by the finishing roller group 417 to a desired tube shape. Then, the cutting unit 419 cuts the tube 102 to a predetermined size, and the tube 102 is completed. 418 is a pulse generator that controls the cutting operation of the cutting unit 419.

Tube 10 with the outer surface coated with solder as described above
2, a plurality of tubes 102 are arranged and corrugated fins 103 are arranged between them, and an inlet tank 104, an outlet tank 105 and an intermediate tank 106 are temporarily attached to the upper and lower ends of the tube 102, and a furnace (not shown) is provided. The heater 101 as shown in FIG. 3 is assembled by melting the solder inside and then solidifying the solder.

Here, when the corrugated fins are laminated between the tubes 102, since the tube 102 has a cross-sectionally convex shape, when the corrugated fins 103 are pressed against the flat side surface of the tube, the central convex shape is The tube is elastically deformed inward by elastic force, and as a result, when the fin and the tube are assembled, the flat side surface of the tube is not arcuate but flat. Therefore, the joint between the tube and the corrugated fin can be ensured sufficiently reliably. If the cross-sectional shape of the tube 102 is not a convex shape but a concave shape that is recessed inward, there is a space between the tube and the corrugated fin when they are joined. However, the problem arises that the two are not joined sufficiently.

In the embodiment described above, the tube 102 and the corrugated fin 103 are made of a material made of aluminum alloy, but they may be made of a material such as brass. Further, the shape of the dimples 120a, b formed on the tube 102 was an elliptical shape in the front view, but the shape is not limited to this and may be changed to a round shape, a square shape, or the like. It is possible. Also, one dimple 120a, 120b is attached to each side of the central flat portion 121, 120,
You may make it arrange | position the number of each.

[Brief description of drawings]

FIG. 1 shows a tube according to an embodiment of the present invention. FIG. 1 (a) is a plan view thereof, FIG. 1 (b) is a view of the tube seen from an open cross section, and FIG. (A) is a plan view thereof, (b) is a view seen from an opening end, FIG. 3 is a perspective view showing an embodiment when the present invention is used for a heater core, and FIG. 4 is FIG. 5 is a schematic view showing a tube forming apparatus, FIG. 5 is a schematic view sequentially showing steps of forming a tube, and FIG. 6 is a partial sectional perspective view showing an example of a conventional tube. 101 …… Heater, 102 …… Flat tube, 103 …… Corrugated fin, 120a, 120b …… Rimple, 121,122 …… Flat part, 1
30 ... core metal.

Claims (1)

[Claims] 1. A tubular tube having a flat cross section perpendicular to the axis, and wavy fins joined to the flat side surface of the tube, wherein the tube is formed by bending a strip-shaped plate material and joining its ends. Is formed into a flat tubular shape by a plurality of projections that project toward the inside of the tube on the flat side surface of the tube, and the projections have a flat portion with a predetermined width at the center in the width direction of the tube. The heat exchanger in which the flat side surface of the tube is formed into an arc shape from the inside of the tube to the outside of the tube in a cross section perpendicular to the axis.