JP2002295990A - Header structure for heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a header structure in which the number of parts can be reduced and the quality and reliability of brazed parts can be improved by using an end plate also as a part of the header. SOLUTION: The end plate has an outline extending to the outer peripheral edge of a flange of the header and a cylindrical recessed part with a bottom having an inside diameter to which the end of a shell can be internally fitted in a central part to serve also as the header having the flange on the outer periphery of the recessed part. Otherwise, an annular diameter reduced part protrudes toward the inside diameter side in the end of the shell to form the abutting part of the end plate to be internally fitted from an opening end. An annular diameter enlarged part is projected toward an outside diameter side nearer to an end edge side than to the diameter reduced part to form an abutting part of the flange to be externally fitted from the opening end.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a header structure of a heat exchanger used for an EGR gas cooling device or the like.

[0002]

2. Description of the Related Art Conventionally, a heat exchanger used in an EGR gas cooling apparatus has a header 3 integrally mounted with a flange 5 at an end of a shell 2 in which an end plate 1 is fitted as shown in FIG. The end plate 1 is fixed in position by covering from the outer peripheral side. A large number of cooling pipes 4 penetrate the end plate 1 so that exhaust gas can pass through the inside of the pipes, and cooling water can pass outside the pipes. Also, as shown in FIG.
At the end of the header 3 on the fitting side, there is provided a fitting portion 3b capable of fitting the end plate 1 and the shell 2 into the same hole, respectively.
And can be brazed at the same time. Furthermore, as shown in FIGS. 8 to 10, a fitting portion (shallow hole) 5 a is formed in the flange 5, and the outer peripheral surface of the end plate 1 and the end of the shell 2 are fitted. Only a cone is used to form a header without a cone. The fitting portion 3b or the flange 5 of these headers 3
Nickel brazing is used to simultaneously join the end plate 1 and the shell 2 to the fitting portion 5a, and a joint structure having high corrosion resistance is obtained.

[Problem] In such a conventional heat exchanger, if the end plate 1, the shell 2, and the header 3 are not securely brazed, a problem occurs due to cooling water leakage. For this reason, the joint between the end plate 1, the shell 2, and the header 3 is required to have tight dimensional accuracy in order to secure an appropriate clearance for obtaining the strength of nickel brazing. As shown in FIG. 11, tight dimensional accuracy is required for both the radial dimension and the axial dimension as shown in FIG. 11, so that the processing becomes difficult and causes an increase in cost. Copper brazing may be used for brazing.
When considering the use environment as an R gas cooling device,
Corrosion may cause a significant reduction in the durability life.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned problems in the prior art, and an object set specifically to solve this problem is that an end plate is a part of a header. Another object of the present invention is to provide a heat exchanger header structure capable of reducing the number of parts and improving the quality and reliability of a brazing portion.

[0005]

According to a first aspect of the present invention, there is provided a heat exchanger header structure according to the present invention, wherein the end plate has an outer peripheral edge of a header flange. Has an outer shape that reaches
At the center, a cylindrical recess with a bottom having an inner diameter to which the end of the shell can be fitted is formed, and the recess is formed on an end plate serving as a header having a flange on the outer periphery. . The header structure of the heat exchanger according to claim 2 is characterized in that a bracket protruding outward from an outer peripheral edge of the end plate is provided.

According to a third aspect of the present invention, there is provided a header structure for a heat exchanger, wherein an annular reduced diameter portion is formed at an end of the shell to protrude radially inward to form an abutting portion of an end plate which fits inside from an opening end. An annular enlarged-diameter portion protrudes toward the outer diameter side on the edge side from the reduced-diameter portion to form a contact portion of a flange fitted outside from the opening end. The header structure of the heat exchanger according to claim 4 is characterized in that an opening end of the shell is enlarged in diameter toward the flange to form a flange fixing portion.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below. However, this embodiment is specifically described for better understanding of the spirit of the invention, and does not limit the contents of the invention unless otherwise specified.

First Embodiment As shown in FIGS. 1 to 4, the header structure of a heat exchanger according to the first embodiment is such that the outer shape of an end plate 11 is an outer peripheral edge of a flange 11a when a header is formed. , And a central portion thereof is formed with a short bottomed cylindrical recess 11b having an inside diameter into which the end of the shell 12 can be fitted.
Is formed on an end plate 11 which also serves as a header and has a flange 11a on the outer periphery of the bracket.

Then, bolt holes 11d, 11d, 11e, 11e necessary for assembling and attaching the heat exchanger are formed in the flange 11a and the bracket 11c. Also,
A large number of cooling pipes 14,..., 14
At right angles to and parallel to the bottom surface so that exhaust gases can pass in the axial direction of the heat exchanger.

In the header structure of the heat exchanger according to the first embodiment configured as described above, the heat exchanger can be formed by brazing the two parts of the end plate 11 and the shell 12 which also serve as the header. Compared with the conventional brazing of three parts of the end plate, the header and the shell, the quality and reliability of brazing are improved, the manufacture of the heat exchanger is facilitated, and the product quality can be improved. Costs can be reduced.

It is only necessary to control the flatness of the end face of the shell 12 for the dimensional control of brazing, so that it is easy to manufacture parts and the precision of parts can be increased.
Moreover, the cost of parts can be reduced. For this reason, dimensional accuracy and parallelism between the flanges of the heat exchanger can be easily ensured. Further, since the end plate 11 is formed of a thin plate press-formed product, the formability is better and the cost can be reduced as compared with a conventional thick plate press-formed product.

Second Embodiment As shown in FIG. 5, a header structure of a heat exchanger according to a second embodiment is configured such that an end plate 21 In addition, the shell 22 has an annular diameter-reduced portion (bead) at a position located a predetermined distance behind the opening end 22c.
22a is projected toward the inner diameter side, and the reduced diameter portion 22a forms an abutting portion of the end plate 21 which is fitted in from the opening end 22c, and the annular expanding portion is closer to the opening end 22c than the position where the reduced diameter portion 22a is formed. The diameter portion (stopper) 22b protrudes toward the outer diameter side, and the enlarged diameter portion 22b forms a contact portion of the flange 23 fitted outside from the opening end 22c, and further extends the opening end 22c of the shell 22 over the entire circumference. The diameter of the flange 23 is increased or expanded so as to be in close contact with the lower end of the flange 23 abutting on the flange 22b to form a flange fixing portion on the opening end 22c side.

The end plate 21 is brought into close contact with a reduced diameter portion 22a provided inside the end face of the shell 22 by a predetermined dimension,
The flange 23 is closely attached to an enlarged diameter portion 22b provided outside the end face of the shell 22 by a predetermined dimension, and the opening end 22c of the shell 22 is enlarged or expanded and fixed, and then each part is brazed. Stick.

In the header structure of the heat exchanger according to the second embodiment configured as described above, the end portion of the shell 22 can be extended without re-forming the header. The parts of the shell 22 and the flange 23 can be easily manufactured, and the number of parts can be reduced, and the number of assembling steps can be reduced.

As for brazing, brazing is provided at a contact portion between the reduced diameter portion 22a of the shell 22 and the end plate 21, and brazing is performed.
2 or between the flange 23 and the shell 2
2 can be brazed by providing a brazing at the fitting portion,
Since each counterpart is limited to one part, the quality and reliability of brazing are improved compared to the case where a number of parts (conventionally three parts) are assembled at the brazing point and brazed together. In addition, the manufacture of the heat exchanger becomes easy, the product quality can be improved, and the cost can be reduced.

[0016]

As described above, in the header structure of the heat exchanger according to the first aspect of the present invention, the end plate has an outer shape reaching the outer peripheral edge of the flange of the header, and the end of the shell is formed in the center portion. By forming a bottomed cylindrical recess having an inside diameter that can be fitted and forming a header-end plate having a flange on the outer periphery of the recess, the conventional end plate, header and shell are brazed. As compared with the case, the brazing quality is improved and the reliability can be increased. In addition, dimension management of brazing,
Since parts can be easily manufactured and the precision of the parts can be increased, and the price of the parts can be reduced, the dimensional accuracy and parallelism between the flanges of the heat exchanger can be easily secured, and brazing can be performed. As a result, the quality and formability can be improved, and the product cost can be reduced.

Further, in the header structure of the heat exchanger according to the second aspect, since the bracket protruding outward from the outer peripheral edge of the end plate is protruded, press working can be performed, and the formability can be improved, and the header structure can be improved. By forming the flange and the bracket in a step structure, the strength of the header can be increased.

Further, in the header structure of the heat exchanger according to the third aspect, an annular reduced diameter portion is formed at the end of the shell so as to protrude toward the inner diameter side and form a contact portion of an end plate which is fitted inside from the opening end. The extent to which the end of the shell is extended is formed by forming an abutting portion of a flange which projects an outer diameter side to the outer diameter side on the edge side from the reduced diameter portion and which is fitted outside from the opening end. Therefore, it is not necessary to separately form a header, so that parts such as end plates, shells, and flanges can be easily manufactured, and the number of parts can be reduced and the number of assembling steps can be reduced. In addition, since the number of mating parts to be joined is limited to one in brazing, the quality of brazing is lower than when a large number of parts (conventionally three parts) are assembled and brazed at a brazing point. In addition, the reliability is improved, the manufacture of the heat exchanger is facilitated, the product quality can be improved, and the cost can be reduced.

Further, in the header structure of the heat exchanger according to the fourth aspect, the opening end of the shell is enlarged toward the flange side to form the flange fixing portion, so that the flange can be formed without forming the header separately. Can be formed, the number of parts can be reduced, and the number of assembly steps can be reduced.

[Brief description of the drawings]

FIG. 1 is an enlarged partial side sectional view showing a header structure of a heat exchanger according to a first embodiment of the present invention.

FIG. 2 is a front view showing an end plate serving also as a header of the heat exchanger according to the first embodiment of the present invention.

FIG. 3 is a side view showing an end plate serving also as a header of the heat exchanger according to the first embodiment of the present invention.

FIG. 4 is an explanatory side sectional view showing a shell of the heat exchanger according to the first embodiment of the present invention.

FIG. 5 is an enlarged partial side sectional view showing a header structure of a heat exchanger according to a second embodiment of the present invention.

FIG. 6 is an enlarged partial cross-sectional side view showing an example in which an end plate is fitted to an end of a shell in a header structure of a conventional heat exchanger.

FIG. 7 is an enlarged partial cross-sectional side view showing an example in which an end plate and an end of a shell are fitted into a fitting portion of a header in a header structure of a conventional heat exchanger.

FIG. 8 is an enlarged partial cross-sectional side view showing an example of a conventional heat exchanger header structure without a header.

FIG. 9 is a plan view showing a flange in a header structure of a conventional heat exchanger without a header.

FIG. 10 is a side cross-sectional view showing a flange in a header structure of a conventional heat exchanger without a header.

FIG. 11 is an explanatory side sectional view showing a shell in a header structure of a conventional heat exchanger without a header.

[Explanation of symbols]

 1,11,21 End plate 11a Flange 11b Depression 11c Bracket 2,12,22 Shell 3 Header 5 Flange 14 Cooling pipe 22a Reduced diameter part 22b Large diameter part 23 Flange

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shigeki Kimura 2002-1 Endo, Fujisawa-shi, Kanagawa Prefecture Inside Tokyo Eater Manufacturing Co., Ltd. (72) Inventor Shin Susumu 2002-1 Endo, Fujisawa-shi, Kanagawa Tokyo Eater (72) Inventor Kenzo Oki 5-24-15 Minamidai, Nakano-ku, Tokyo Calso-Nic Kansei Corporation (72) Inventor Tatsuo Ozawa 5-24-15 Minamidai, Nakano-ku, Tokyo Calso-Nic Kansei Inside the corporation

Claims (4)

[Claims] 1. An end plate having an outer shape reaching an outer peripheral edge of a flange of a header, and a central cylindrical portion having a bottomed cylindrical recess having an inner diameter into which an end of a shell can be fitted, and an outer periphery of the recess. A header structure for a heat exchanger, wherein the end plate is formed on a header and end plate having a flange. 2. The header structure for a heat exchanger according to claim 1, wherein a bracket protrudes outward from an outer peripheral edge of said end plate. 3. An annular diameter-reducing portion is formed at the end of the shell so as to protrude toward the inner diameter side to form an abutting portion of an end plate which fits inside from the opening end, and an annular diameter-enlarging portion is provided closer to the edge than the diameter-reducing portion. A header structure for a heat exchanger, wherein a contact portion of a flange is formed by projecting an outer diameter side to fit outside the opening end. 4. A header structure for a heat exchanger according to claim 3, wherein an opening end of said shell is enlarged toward said flange to form a flange fixing portion.