JP3087130B2 - Brazing method for metal materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brazing method for metal materials, and more particularly, to a method for manufacturing an intake manifold for automobiles, a heat exchanger, and the like. The present invention relates to a method of brazing both metal materials by a method of placing the two metal materials in a state of being inserted into a hole formed in the second metal material.

[0002] In this specification, the term "aluminum" shall include aluminum alloys in addition to pure aluminum. In this specification, the term "hole" includes a bottomed hole in addition to a through hole.

[0003]

2. Description of the Related Art Conventionally, to braze a metal pipe and a cylindrical metal part having a hole into which an end of the metal pipe is inserted by brazing, for example, as shown in FIG.
A large-diameter portion (33) is formed at the opening end of the inner peripheral surface of the hole (31) of (30) through a step (32), and the end of the metal pipe (34) is Insert the part (30) into the large-diameter part (33) of the hole (31) and bring its end face into contact with the step (32), and fit it to the part outside the hole (31) of the metal pipe (34). A ring-shaped brazing material (35) having a circular cross section was fitted and covered.

[0004]

However, when brazing is performed by a conventional method, as shown in FIG.
The fillet (36) is only partially formed at intervals in the circumferential direction between the end face of the (34) and the step (32) of the cylindrical metal part (30), and the bonding strength There was a problem that there was a shortage. In addition, there is a problem that moisture invades from a portion where the fillet (36) is not formed, reacts with the residue of the flux, and causes corrosion on the metal tube and metal parts.

An object of the present invention is to provide a method for brazing a metal material which solves the above-mentioned problems.

[0006]

According to the present invention, there is provided a method for brazing a metal material, comprising: a first metal material having a cylindrical portion; and a second metal material having a hole into which an end of the cylindrical portion of the first metal material is inserted. And a large-diameter portion is formed at the open end of the inner peripheral surface of the hole of the second metal material via a step, and the cylindrical portion of the first metal material is formed into the second metal material. In brazing both metal materials by a method of being inserted into the large diameter portion of the formed hole and placing the end surface of the cylindrical portion in contact with the step portion, the end surface of the cylindrical portion of the first metal material, A plurality of recesses for forming a fillet are formed in one of the step and the step at intervals in the circumferential direction.

[0007] In the above, the size of the fillet forming recesses, and the amount of brazing material to be used, after brazing fillet
The amount is preferably such that the recess is completely filled with the brazing material.

In the above, as the first metal material and the second metal material, for example, JISA1000 series, 3000
A series, 6000 series, or 7000 series aluminum is used. In this case, the brazing material used is, for example, an Al-6.8 to 11.7 wt% Si alloy, and the flux used is, for example, a chloride-based or fluoride-based flux. Further, it is preferable to heat to about 580 to 620 ° C. in a nitrogen gas atmosphere or an air atmosphere.

[0009]

According to the method for brazing a metal material of the present invention, the brazing material melted by heating during the brazing firstly has an outer peripheral surface of the cylindrical portion of the first metal material and a large hole of the second metal material. Fi between the passes between the diameter inner peripheral surface flows into the recesses for the fillet formation, and then the end face and the stepped portion of the cylindrical portion of the first metal member
It flows into both sides of the let forming recess. Therefore, the space between the end surface of the cylindrical portion of the first metal material and the step portion is provided.
A fillet is formed over the entire circumference including the portion for forming the fillet.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the method of the present invention is applied to the manufacture of an intake manifold for an automobile.

FIG. 5 shows an automobile intake manifold.
The intake manifold (1) has one end open and the other end closed, a plurality of holes (3) formed in the peripheral wall, and a cylindrical projection (4) for connecting a branch pipe around each hole (3). Plenum chamber (2) made of wrought aluminum and integrally provided with one end, and each end has a cylindrical outward projection for connecting a branch pipe.
And (4) a plurality of branch pipes (5) made of wrought aluminum brazed in a fitted state. As the plenum chamber (2) and the branch pipe (5), for example, JIS
A6063, JISA600 such as JISA6061
It is preferable to use one made of a zero-type aluminum material.

At the open end of the plenum chamber (2), a throttle body mounting body (6) made of aluminum casting is brazed. A throttle body (not shown) is attached to the throttle body attachment (6), and an air supply pipe from an air cleaner is connected to the throttle body.

The other end of each branch pipe (5) is brazed together to a connecting member (7) to a cylinder head made of aluminum casting. Each branch pipe (5) via connecting member (7)
Are connected to a cylinder head of an engine (not shown).

The throttle body attachment (6) is cylindrical,
One end is integrally provided with an outward flange (8). One open end of the plenum chamber (2) is inserted into a hole (9) of the throttle body mounting body (6) and brazed to the throttle body mounting body (6).

The connecting member (7) has a horizontal rectangular shape and four holes (not shown), and a branch pipe connecting cylindrical projection (10) provided integrally around the hole. I have. Above the protruding portion (10), an insertion portion (11) of the fuel injection device is integrally provided. The branch pipe (5) is inserted into the protruding part (10) and brazed.

The method of the present invention is applied to, for example, brazing the open end of the plenum chamber (2) to the throttle body mounting body (6).

Referring now to FIGS. 1 and 2, the open end of the plenum chamber (2) and the throttle body mounting body will be described.
(6) The brazing method will be described.

First, the hole of the throttle body mounting body (6)
A large-diameter portion (14) is formed on the inner peripheral surface of (9) at an end opposite to the flange (8) via a step (13). Further, a plurality of recesses (15) for forming a fillet are formed in the open end face of the plenum chamber (2) at equal intervals in the circumferential direction. The circumferential length of the fillet forming recess (15) is 0.5
mm or more, and the depth is preferably 0.5 to 5.0 mm. The number of the fillet forming recesses (15) is preferably four or more.

Next, the open end of the plenum chamber (2) is connected to the large diameter portion (14) of the hole (9) of the throttle body mounting body (6).
A ring-shaped brazing material (16) is fitted over the outer peripheral surface of the plenum chamber (2) so as to be in contact with the end surface of the throttle body mounting body (6) opposite to the flange (8). Then, in a furnace, a plenum chamber (2) and a throttle body mounting body (using a chloride-based or fluoride-based flux and heating to about 580 to 620 ° C. in a nitrogen gas atmosphere or an air atmosphere). 6) Brazing with.

The brazing material melted by heating during brazing is
First, it passes between the outer peripheral surface of the plenum chamber (2) and the inner peripheral surface of the large-diameter portion (14) of the hole (9) of the throttle body mounting body (6) and enters the fillet forming recess (15). And then on both sides of the filleting recess (15) in the portion between the end face of the plenum chamber (2) and the step (13). Thus, a fillet (17) is formed between the end face of the plenum chamber (2) and the step (13) over the entire circumference, including the portion of the recess (15) for forming a fillet . As a matter of course, a fillet (17) is also formed between the outer peripheral surface of the plenum chamber (2) and the inner peripheral surface of the large diameter portion (14).

Incidentally, in the intake manifold (1), the brazing of the plenum chamber (2) and the throttle body mounting body (6) usually branches off with the cylindrical projection (4) of the plenum chamber (2). Pipe (5), branch pipe (5) and connecting member
This is performed simultaneously with the brazing of the cylindrical projection (10) of (7). In this case, the branch pipe (5) and the connecting member (7) are also combined, and the main pipe (2) and the cylindrical protrusion (4) of the branch pipe (5), and the branch pipe (5) and the connecting member (7) are combined. The brazing material is also arranged between the cylindrical projection (10). Then, the main pipe (2), the branch pipe (5), the throttle body mounting body (6), and the connection member (7) are combined with the cylindrical projections (4) and (10) oriented vertically upward. Put the body into the furnace and connect with the cylindrical projection (4) of the plenum chamber (2) and the branch pipe (5), the plenum chamber (2) and the throttle body attachment (6), and the branch pipe (5). Element
(7) is brazed together with the cylindrical projection (10). Thus, the intake manifold (1) is manufactured.

[0023]

[Specific experimental example] Outer diameter 60 mm, wall thickness 2.5 mm
The plenum chamber (2) has a depth of 1.0
mm, circumferentially 1.0 mm long fillet-forming recess
(15) is divided into six, eight or sixteen at equal intervals in the circumferential direction.
Individually formed. Then, a ring brazing material (16) made of an Al-9 wt% Si alloy is used, and a chloride flux is used in a furnace at 600 ° C. in a nitrogen gas atmosphere at 600 ° C. for 5 hours.
After heating for one minute, the plenum chamber (2) and the throttle body attachment (6) were brazed. Then the plenum chamber
The portion between the end face of (2) and the step (13) was observed. As a result, in each case, the fillet (17) was formed over the entire circumference. Further, the recess (15) for forming a fillet was also filled with the fillet.

For comparison, the plenum chamber was the same as above except that no fillet forming recess was formed.
(2) and the throttle body attachment (6) were brazed, and the portion between the end face of the plenum chamber (2) and the step (13) was observed. As a result, the fillet was formed at a plurality of locations at intervals in the circumferential direction, and the total circumferential length of each portion was less than 5/6 of the entire circumferential length.

FIGS. 3 and 4 show a second embodiment of the present invention. 3 and FIG. 4, the same parts as those shown in FIG. 1 and FIG.

A fillet forming recess (20) having a circumferential length slightly shorter than １ ／ of the entire circumferential length of the end face is formed on the open end face of the plenum chamber (2). Four are formed at equal intervals in the direction. Fillet adjacent in the circumferential direction
Tsu preparative forming recesses (20) if the interval between the in 0.5mm or more, the depth is to leave this as the 0.5 to 5.0 mm. In addition, full
The number of recesses (20) for forming a fillet is preferably three or more. Next, the plenum chamber (2) and the throttle body attachment (6) are brazed in the same manner as in the first embodiment.

The brazing material melted by heating during brazing is
First, it passes between the outer peripheral surface of the plenum chamber (2) and the inner peripheral surface of the large-diameter portion (14) of the hole (9) of the throttle body mounting body (6) and enters the fillet forming recess (20). And then on both sides of the fillet forming recess (20) in the portion between the end face of the plenum chamber (2) and the step (13). In this way, a fillet (17) is formed between the end face of the plenum chamber (2) and the step (13) over the entire circumference, including the portion of the recess (20) for forming a fillet .

[0028]

[Specific experimental example] Outer diameter 60 mm, wall thickness 2.5 mm
The plenum chamber (2) has a depth of 1.0
The four recesses (20) for forming a fillet of 20 mm were formed at intervals of 1.0 mm in the circumferential direction. And a ring-shaped brazing material made of an Al-9 wt% Si alloy (16)
Using a chloride flux, the mixture was heated in a furnace at 600 ° C. for 5 minutes in a nitrogen gas atmosphere, and the plenum chamber (2) and the throttle body attachment (6) were brazed. Thereafter, the portion between the end face of the plenum chamber (2) and the step (13) was observed. As a result, fillets were formed over the entire circumference. Also, recesses for forming fillets
(20) was also filled with fillets.

In the above two embodiments, fillet forming recesses (15) (2) are formed in the open end face of the plenum chamber (2).
However, instead of this, a plurality of fillet forming recesses may be formed in the step portion (13) of the throttle body mounting body (6) at intervals in the circumferential direction.

[0030]

According to the method for brazing a metal material of the present invention, as described above, a portion of the recess for forming a fillet is provided between the end surface of the cylindrical portion of the first metal material and the step. The fillet is formed over the entire circumference including the above. Therefore,
The joining strength is increased as compared with the conventional method. Moreover, corrosion of the metal material can be prevented.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is an enlarged sectional view of a state before brazing a plenum chamber of an intake manifold and a throttle body mounting body.

FIG. 2 is a partially cutaway perspective view after brazing.

FIG. 3 is an enlarged sectional view of another embodiment of the present invention, showing a state before brazing of a plenum chamber of an intake manifold and a throttle body mounting body.

FIG. 4 is a partially cutaway perspective view after brazing.

FIG. 5 is a perspective view showing an intake manifold.

FIG. 6 is an enlarged sectional view showing a conventional method, in a state before brazing a metal pipe and a tubular metal part.

FIG. 7 is an enlarged sectional view showing a state after brazing.

[Explanation of symbols]

2 Plenum chamber (first metal material) 6 Throttle body mounting body (second metal material) 9 Hole 13 Step 14 Large diameter portion 15 Fillet forming recess 20 Fillet forming recess

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-51-9044 (JP, A) JP-A 62-77663 (JP, U) JP-A 56-55559 (JP, U) 9453 (JP, B1) (58) Field surveyed (Int. Cl. ⁷ , DB name) B23K 1/00-1/20

Claims (1)

(57) [Claims] A first metal material having a cylindrical portion and a second metal material having a hole into which an end of the cylindrical portion of the first metal material is inserted are prepared, and an inner periphery of the hole of the second metal material is prepared. A large-diameter portion is formed at the opening-side end of the surface through a step, and the cylindrical portion of the first metal material is inserted into the large-diameter portion of the hole formed in the second metal material to form the cylindrical portion. In brazing both metal materials by a brazing method in which the end surface is placed in contact with the stepped portion, an interval in the circumferential direction is provided on one of the end surface of the cylindrical portion of the first metal material and the stepped portion. A plurality of recesses for forming a fillet are formed in the brazing step.