JPS6115359B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aluminum heat exchanger used in automobile radiators and the like.

Conventionally, heat exchangers used in automobile radiators, for example, are made by stacking a plurality of aluminum plate fins that are formed by regularly squeezing open protrusions at regular intervals. By stacking upper and lower aluminum seat plates each having a collared hole on each side and brazing the joints of the opening protrusions, the continuously joined opening protrusions can be used as a liquid passage pipe. In addition, the plate portion was formed as a fin (see Japanese Utility Model Application No. 70361/1983).

However, when heat exchangers are manufactured by such a method, not only is the brazing process complicated and difficult to mechanize, but there are also disadvantages such as incomplete brazing, resulting in defective products with leaks, etc. Moreover, since the inner surface of the liquid passage tube formed in this way is susceptible to corrosion, a painting process is required.
However, the thermal expansion coefficients of the brazed aluminum pipe and the paint resin layer coated on its surface are significantly different, so a temperature difference of 100 to 200°C between when in use and when not in use There was a drawback that the resin layer peeled off due to the long-term thermal expansion and contraction that occurred.

In order to improve the shortcomings of the brazing method, a method was proposed in which a synthetic resin adhesive was applied to the joint, and as a result, a liquid passage pipe section formed by laminating the upper and lower seat plates and plate fins was proposed. The inner surface was covered with a resin film made of adhesive, which was advantageous in terms of corrosion resistance. (Refer to Japanese Patent Application Laid-open No. 47-26742). However, the core formed in this way and the heat exchanger formed from the core have a resin coating on parts unrelated to the joining, such as the seat plate surface (tank side), the inner surface of the tank, and the inner surfaces of the inlet and outlet pipes. Therefore, the corrosion resistance of these end-coated parts was poor.

On the other hand, an aluminum liquid passage pipe is inserted into the opening protrusions of a plurality of aluminum plate fins with regular perforated protrusions formed at regular intervals, and all parts are joined by mechanical bonding. A method is proposed. For example, as shown in FIG. 1, the liquid passage tube 1 of the core part configured by inserting the liquid passage tube as described above and the upper and lower aluminum seat plates 3 each having a hole with a collar 2, An elastic sealing member 4 having a shape that matches this is used to insert the liquid through the tube, and the liquid passage tube 1 is expanded at the seat plate portion to bring the seat plate 3 and the liquid passage tube 1 into close contact, and the peripheral portion is caulked. Tank 5 is installed. However, this structure is expensive because the elastic sealing member is required as a separate part, and the tank is fixed by caulking the seat plate, so the seat plate requires considerable strength. This increases the plate thickness and weight. Further, when a synthetic resin tank is used as a structural member, aluminum is used except for the tank and the sealing member, but aluminum is easily corroded. Furthermore, although the structure is such that the joint between the seat plate and the liquid pipe is expanded and then firmly sealed, it has the disadvantage that a high degree of skill is required in the construction method in order to obtain high yield and reliability.

The present invention was made in order to improve the various drawbacks of the conventional products as described above, and is made of a plurality of aluminum plate fins in which short cylindrical opening protrusions are squeezed out regularly at regular intervals. Upper and lower aluminum seat plates each having a protruding opening in the same shape are stacked by fitting the protruding opening into the opening of another fin, and the adhesive is flowed down into these fitting parts. The fitting portions are joined to form a core portion on which an adhesive layer is formed, and the core portion is provided with:
The upper tank to which the inlet pipe is joined and the lower tank to which the outlet pipe is joined are joined by caulking via a sealing member,
The present invention is characterized in that a liquid coating synthetic resin is flowed into the heat exchanger body from the inlet pipe or the outlet pipe to form a resin coating over the entire inner surface of the heat exchanger body.

Next, one embodiment of the present invention will be described with reference to the drawings. That is, as shown in FIGS. 2 and 3, short cylindrical opening protrusions 11 are formed regularly at regular intervals.
A plurality of aluminum plate fins 12, 12, . The seat plates 14 and 15 have opening protrusions 11 and 13 thereof.
Opening 16 of the other fin or opening 1 of the seat plate 15
3 and are stacked so as to fit together. As a result, a liquid passage pipe portion 17 is formed in the opening protrusions 11 and 13. A liquid adhesive is applied to the liquid passage pipe portion 17 by fluidization, and then inserted and hardened in an atmospheric furnace under appropriate temperature conditions to form a core portion.
Liquid passage pipe portion 17 of the core portion thus obtained
As shown in FIG. 3, an adhesive layer 18 is interposed between each protrusion 11 and 13, and the inner surface is
covered by 8.

As shown in FIG.
Atsupa tank 20 joined by brazing etc.
is joined to the upper plate 14 by caulking via a sealing member such as an adhesive or an elastic sealing member. Similarly, the lower tank 22 to which the outlet pipe 21 is joined is joined to the lower plate 15 by caulking via the sealing member. Next, the pipe section 19 (or 2
1) A more liquid synthetic resin (liquid adhesive or paint) flows into the heat exchanger so as to fill it,
After coating the entire interior of the heat exchanger so as to make contact with it, excess resin is discharged, and the synthetic resin coating 23 is formed on the inner surface by curing again in an atmospheric furnace at the required temperature. In the liquid passage pipe portion 17 of the heat exchanger formed in this way, a synthetic resin layer 23 is further formed on the surface of the adhesive layer 18 as shown in FIG. A synthetic resin layer is formed as shown.

As a caulking method, as shown in FIG.
The end edges may be caulked and then the synthetic resin layer 23 may be formed on the inner surface.

The adhesive used in the present invention preferably satisfies adhesive strength, heat resistance, chemical resistance, water resistance, etc. For example, examples include phenolic resins, polyurethane resins, epoxy resins, and modified resins thereof. Similarly, liquid resin for resin coating requires similar conditions. Furthermore, as shown in FIG. 5, for example, the adhesive layer 18 requires strength but does not require much water resistance, and the coating resin 23 is made of a material with good water resistance and chemical resistance. may be used.

As described above, in the heat exchanger according to the present invention, the entire inner surface of the metal part of the core part is covered with the resin film, so that the corrosion resistance is significantly improved. Therefore, there is no need to add corrosion resistance to the material forming the heat exchanger body, and inexpensive materials can be used.
Furthermore, since the inner surface of the tank is covered with a resin film for the core portion joined by caulking via an elastic sealing member using a resin tank, water absorption and swelling can be prevented. Furthermore, the most important thing is that each of the many opening protrusions that make up the liquid passage tube is individually bonded with adhesive, so compared to the case where a resin coating is formed on the inner surface of a straight aluminum tube, , the expansion coefficient with its surface resin coating is 100~120℃
Since the adhesive itself exhibits the same expansion as the resin film even if the temperature varies significantly due to the temperature difference, it can be absorbed sufficiently and has almost no effect, and there are no problems such as peeling.

[Brief explanation of the drawing]

Fig. 1 is a partial cross-sectional view showing the structure of a conventional heat exchanger, Fig. 2 is a cross-sectional view showing the core portion of a heat exchanger according to the present invention, and Fig. 3 shows the core shown in Fig. 2 joined with adhesive. 4 is a sectional view of the heat exchanger according to the present invention, FIG. 5 is a partial enlarged sectional view of the main part of FIG. 4, and FIG. 6 is another embodiment of the caulking part. FIG. 11, 13... Opening protrusion, 12... Plate fin, 14, 15... Seat plate, 16... Opening, 1
7... Liquid passage pipe section, 18... Adhesive layer, 19, 21
... Pipe, 20, 22 ... Tank, 23 ... Synthetic resin layer.

Claims (1)

[Scope of Claims] 1. A plurality of aluminum plate fins in which short cylindrical opening protrusions are squeezed out regularly at regular intervals, and upper and lower aluminum seats each having opening protrusions of similar shape. An adhesive layer was formed by stacking the plates by fitting the protruding openings into the openings of other fins, and joining the fitting parts by flowing adhesive down into these fitting parts. A core part is formed, and an upper tank to which an inlet pipe is joined and a lower tank to which an outlet pipe is joined are joined to the core part by caulking via a sealing member, and heat exchange is performed from the inlet pipe or outlet pipe. A heat exchanger characterized in that a liquid coating synthetic resin is flowed into the interior of the heat exchanger body to form a warp resin coating over the entire inner surface of the heat exchanger body. 2. The heat exchanger according to claim 1, wherein the sealing member is an adhesive. 3. The heat exchanger according to claim 1, wherein the sealing member is an elastic sealing member.