JPH03165840A - Metallic support - Google Patents

Abstract

PURPOSE:To relax thermal stress by allowing a space part where a corrugated foil is not present thereon to be fitted with a narrow-width corrugated foil having a width equal to the width of the space on the surface of a flat foil. CONSTITUTION:Two narrow-width corrugated foils 2a, 2b are arranged on both sides on the surface of a flat foil 1 with a space 3 between them so that respective width ends are allowed to conform to the width ends of the flat foil, respectively. A narrow-width corrugated foil 2c having a width equal to that of a space 3 is provided on the position, on the rear surface of the flat foil 1, corresponding to the above space 3 provided on the surface. Subsequently, the flat foil 1 and the corrugated foils 2a-2c mentioned above are simultaneously interposed between electrode pairs 4a, 4b, respectively, and pressurization and energizing are performed by means of respective pointed ends of the above electrode pairs 4a, 4b, by which both foils 1, 2 interposed as mentioned above are subjected to direct spot welding. The resulting honeycomb body 7 is held and fixed in an external cylinder 8. By this method, thermal stress can be relaxed while securing sufficient joining strength in an axial direction and a radial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a support (carrier) for supporting a catalyst when the gas emitted from an engine of an automobile or the like is purified using a catalyst. In particular, it relates to carriers that have been devised in the joining method, which is a problem with metal carriers.

(Prior art) Conventionally, catalyst carriers for exhaust gas purification have mainly been ceramic honeycomb bodies whose main component is cordierite. Metal carriers have been developed as an alternative, and some have already been put into practical use.

The metal carrier is made of stainless steel or corrosion-resistant high alloy steel as a foil of around 50 μm, which is formed into a corrugated shape, and then the corrugated foil and flat foil are layered and wound or laminated to create a honeycomb-shaped cylinder. is placed in an outer cylinder made of stainless steel, high alloy steel, etc. with a thickness of about 1 to 2III1, and the contact area between the corrugated foil and flat foil that constitute this honeycomb body, the outer periphery of the honeycomb body, and the inner periphery of the outer cylinder are heated with wax. It is manufactured by brazing and fixing the material.

With this brazing method, the honeycomb body and the outer cylinder are almost entirely joined, creating a rigid structure, but if such a carrier is installed in an automobile engine exhaust gas system, it will not only cause vibrations during driving, but also However, the heat cycle of rapid heating and rapid cooling is repeated, causing thermal stress, and stress tends to concentrate especially on the honeycomb body near the outer cylinder, resulting in peeling and cracking of the foil joints. Sometimes. In order to resolve these inconveniences, there are several proposals for devising bonding methods, such as partially bonding the honeycomb bodies, but to achieve this, the process becomes complicated or a drastic solution is required. It is not. On the other hand, the brazing alloy and brazing process are expensive, and the cost problem remains unsolved using this method.

Recently, many proposals have been made as an alternative to brazing. There are methods using high-density energy such as lasers and electron beams, and methods using resistance welding.
Publication No. 71547 discloses that a flat plate (foil) and a corrugated plate (foil) are spot welded and then rolled up to form a honeycomb body. Since the parts that are joined are not joined to the adjacent plates, if force is applied in the axial direction of the honeycomb body, there is a possibility that it will shift in the axial direction like a bamboo shoot. Also, JP-A-8
4-40180, a flat plate and a corrugated plate are used, and the phase is set to 1.
In the process of winding the electrodes with a shift of 800 mm, two electrodes are made into a set from the outside, and one or more sets of these are lined up and resistance welded. However, according to this method, welding can only be performed in a specific range on the core circumference, there is a limit to the number of electrodes arranged, the welding process and the winding process are serial, and the welding is continuous, so Manufacturing takes time and there are problems with productivity.

(Problems to be Solved by the Invention) The present invention proposes that the corrugated foil and the flat foil can be bonded using known brazing or
Any method such as electron beam welding or laser beam welding can be used, but in particular, spot resistance welding using multiple electrodes allows for efficient online joining, as well as making corrugated foil into a nested structure. By doing so, axial movement can be restrained.In other words, the adjacent foils have a fitted structure, making it structurally flexible and sufficiently relieving the thermal stress that occurs during engine operation. The purpose of the present invention is to provide a highly durable metal carrier and a method for manufacturing the same.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following structure.

Namely, 1) In a honeycomb body in which a flat foil and a corrugated foil are overlapped and then laminated or wound, a corrugated foil having a width smaller than that of the flat foil is arranged and bonded to the surface of the flat foil. A narrow wave foil having the same width as the space, which is joined to a position corresponding to the space on the surface of the opposing flat foil, is fitted into the space where no foil exists, and the alternating wave foils are combined in a nested manner. 2) On the opposite side of the space formed on the flat foil surface where no corrugated foil exists, there is a corrugated foil at approximately the same position and the same width as the space. This is a metal carrier having a honeycomb shape, which is characterized by being arranged and bonded.

5 The present invention will be explained in detail below.

The foil used in the present invention is A. 1? It is made of stainless steel containing Fe-Cr-A, 77 series heat-resistant high alloy steel, etc., and has a thickness of 1001 or less, preferably around 501. The width of the flat foil (length in the axial direction when configured into a honeycomb body) varies depending on the product, but is approximately 160 mm.
It is less than or equal to m+e. The width of the corrugated foil must be smaller than the width of the flat foil, but any desired size can be selected within this range.

In the present invention, the flat foil is alternately arranged with narrow corrugated foils of appropriate widths and spaces where no corrugated foil is present on its front and back surfaces, and the narrow corrugated foils are welded by spot welding or the like as described below. Join by means. When these flat foils with narrowly corrugated foils bonded together are laminated or spirally wound and overlapped, the narrowly corrugated foils on one side of the flat foils are adjacent to each other, and the opposing flat foils are uncorrugated. It fits tightly into the space and becomes nested.

In other words, when a honeycomb body is constructed, the corrugated foils bonded to each flat foil are interlocked in a nested manner between two flat foils that are adjacent to each other and are facing each other. The structure is the same as that in the case where the small-width corrugated foil is present, but the narrow-width corrugated foils and the narrow-width corrugated foil and the opposing flat foil that are nested in the space are not bonded to each other.

The width of the corrugated foil to be placed and joined on the front and back sides of the flat foil,
The width dimension of the space to be formed can be arbitrarily selected, but when forming a honeycomb body by laminating or winding flat foils with corrugated foils bonded together, one flat foil space that is adjacent to the other is It is best to arrange the narrow wave foils joined to the opposing flat foils so that they can fit together, that is, the width of one space and the narrow wave foil of the other side are approximately equal. Preferably, this allows the corrugated foils to be tightly nested together and prevents adjacent foils from shifting in the axial direction of the honeycomb body.

As mentioned above, flat foil has small wavy foil on the front and back sides.
They are placed alternately with the spaces and joined together, but when this is rolled to form a spiral honeycomb body, the front and back sides of the flat foils are facing each other because they are rolled one after the other. It becomes a surface. Therefore, the small wave foil that is joined to the front and back of this,
When the flat foils are seen through, it is preferable to arrange the foils so that they do not overlap, as this allows the opposing narrow wave foils to be assembled closely and alternately in a nested manner (claim 2 describes this state). ing.).

However, when narrowly corrugated foil is bonded to a short flat foil and these are stacked one by one to form a honeycomb body, the above embodiment may be used, but the present invention is not limited to this. There is no problem even if the foils overlap when seen through.

A specific example of this is shown in FIG. 9, in which a short flat foil 1a is sandwiched between corrugated foils 2c and 20, which partially overlap.
In the flat foil 1b, the corrugated foil 2f completely overlaps 2g. However, the widths of the hollow portions 3 formed on each of these corrugated foils and the flat foil facing the corrugated foils are set to have the same width.

In this way, the width of the narrow corrugated foil arranged on the flat foil and the width of the hollow part need only be determined in relation to the narrow corrugated foil on the flat foil on the adjacent and opposing side, and are not necessarily the same. When looking through the sheets of flat foil, the narrow wave foils do not need to overlap.

In the present invention, the method for joining flat foil and corrugated foil is brazing,
Although known methods such as resistance welding, laser welding, high-density energy welding such as EB, etc. can be used, resistance spot welding means is most preferred in terms of work efficiency. When resistance spot welding is used, joining and winding of flat foil and single wave foil can be performed in one process. EB, laser, etc. can also be performed in the same process as spot welding. On the other hand, in the case of brazing, you can either braze the corrugated foil to the flat foil in advance and then wind it, or apply adhesive to either the flat foil or the corrugated foil in advance and then wind it. Forming the body
The two foils can be joined by employing a process such as attaching wax powder to the adhesive and then brazing the honeycomb body in a vacuum.

In this way, in the present invention, a space where no corrugated foil exists is provided on each surface of the flat foil, and in a honeycomb body formed by laminating or winding both foils into a spiral shape, the flat foil The corrugated foils bonded to the flat foils facing each other are nested together in the space of 9. Since the corrugated foils are interposed alternately over the entire surface in a non-bonded state between the adjacent flat foils, The structure is capable of absorbing distortion due to thermal stress in the axial and radial directions, and the honeycomb body does not shift in the axial direction, making it possible to significantly improve durability.

Next, the manufacturing method for the wound honeycomb body of the present invention will be specifically explained using an example shown in the drawings.

Figures 1 and 2 show a situation in which they are joined by spot welding, and 1 is a flat foil and 2 is a small corrugated foil. Flat foil 1
On the surface of the two narrow wave foils 2a. 2b are arranged with spaces 3 on both sides of the flat foil so that their respective width ends match the width ends of the flat foil.

Although the widths of the narrow wave foils 2a and 2b can be selected as desired, in the illustrated example, they are of equal width. Further, the space 3, that is, the distance between the corrugated foils 2a and 2b may be any distance, and in the illustrated example, it is set to be the same as the width of the corrugated foils 2a, 2b. On the back surface of the flat foil 1, a narrow wave foil 2c having the same width as the space 3 is arranged at a position corresponding to the space 3 provided on the front surface.

That is, when the plane of the flat foil is seen through, the narrow wave foil 2c is arranged so as not to overlap the small wave foils 2a and 2b and to be approximately V-aligned with the space 3 so that there is no gap.

That is, in this case, the widths of the corrugated foils 2a, 2b, and 2c are all 173 of the width of the flat foils. 4 is a spot welding electrode;
A flat foil 1 and a corrugated foil 2 are placed between the electrode pairs 4a and 4b.
a, 2b, and 2c are simultaneously sandwiched, and the pointed tips are pressurized and energized to directly spot weld the sandwiched foils 1 and 2. It is not necessary to weld all the corrugated parts of the corrugated foil that come into contact with the flat foil, but it can be carried out by selecting appropriate intervals. Also, electrode 4
may be installed in a plurality of upper and lower stages, and the number of each stage can be appropriately selected depending on the joining width, and is not limited to three pairs for one narrow wave foil as in the example shown in the figure. FIG. 2 shows the arrangement of the electrodes 4 as seen from the direction of arrow A in FIG. In the figure, 5 indicates a power supply, and 6 indicates a switch. Further, FIG. 3 shows the arrangement and bonding status of the flat foil 1 and the narrow corrugated foils 2a, 2b, and 2c. From this, when looking through the front and back surfaces of the flat foil, it can be seen that the narrow wave foils are arranged alternately without any gaps.

In this way, the present invention transports the pre-formed small-width corrugated foils 2a, 2b, 2c from a predetermined position while superimposing them on the front and back surfaces of the flat foil 1 being sent in, and spots both foils during this transport process. While welding, roll it into a spiral shape in the direction of arrow B to form a nicum body. At this time, in the space 3 formed between the narrow wave foils 2a and 2b, the narrow wave foil 2C
are fitted, and the narrow wave foils 2a, 2b and 2C on the front and back sides of the flat foil 1 are engaged with each other between the opposing flat foils, as will be described later.

The honeycomb body 7 manufactured in this way is housed in an outer cylinder 8, as a part of the cross section is shown in FIG. 4, and is fixed by a known method such as brazing, welding, or other mechanical means. , it doesn't get any further than this. In addition, in the honeycomb body 7, in the radial direction, one flat foil 1a forms a space 3 with the joined corrugated foils 2a and 2b, and the flat foil 1b adjacent to and facing this space 3 forms a space 3. Wave foil 2C is included.

and flat foil 1a,]. Connected to b and lc respectively 1
2. The corrugated foils 2a, 2b, and 2c are not joined to the opposing surfaces of the adjacent flat foils, but the corrugated foils 2a and 2c are not bonded to each other in the axial direction.
Since the corrugated foils 2c enter the space 3 between the foils 2c and 2c and engage with each other, each foil is restrained from moving in the axial direction and will not shift.

Although the above explanation uses an example of direct spot welding, the present invention is not limited to this, and a joining method using high-density energy such as an electron beam or a laser can also be applied in a similar manner.

(Example) Examples of the present invention will be shown below.

Example 1 A 50 mm thick foil made of ferritic stainless steel containing 15% Cr% 4.5% A11 was processed into a flat foil with a width of 120 mm and a corrugated foil with a width of 40 mm, as shown in Fig. 1. As shown, corrugated foils were alternately stacked on the front and back sides of flat foils, and both foils were joined by direct spot welding.

Welding was performed by pressing both flat wave foils with an electrode with a conical tip and sandwiching the foil between the electrodes. Four pairs of electrodes in one row of 1 3 were arranged on each foil and spot welding was performed on the corrugated foil, which was then wound to form a honeycomb body 7 as shown in FIG.

FIG. 5 shows a partially developed honeycomb body.

The honeycomb body manufactured in this manner was housed in an outer cylinder made of SUS304 stainless steel, fixed by resistance welding, supported, and mounted on a 3000 cc engine.

As a result of continuous operation with the carrier temperature maintained at 850°C in this engine system, even after 300 hours, there was no difference between the outer cylinder and the honeycomb body.
Or, there is no axial shift or damage inside the honeycomb body.
I was able to pass the durability test.

Example 2 A foil was manufactured using the same material as in Example 1, and a honeycomb body shown in FIG. 6 was manufactured. Two sheets of corrugated foil with a width of 60 m+x were arranged alternately, and spot welding was performed at 5 points in a row.

The welding conditions are the same as in Example 1.

When the carrier thus produced was subjected to the same test as in Example 1, the same results as in Example 1 were obtained even after 300 hours had passed, and the carrier passed the durability test.

14 Example 3 A foil was manufactured using the same material as in Example 1, and as shown in FIG. 8(a), a corrugated foil with a small width and the same length as the flat foil was placed on the front and back sides of the short flat foil 1'. 2'a, 2'b, and 2'c are arranged and joined, and these are laminated one by one, and the corrugated foils 2'a, 2'b are joined to the flat foil 1' facing each other. The foil 2'c was inserted to form a laminated honeycomb body, and as shown in FIG. 8(b), the honeycomb body was inserted and fixed into a rectangular outer cylinder 8' of the same quality as in Example 1. The honeycomb body and the honeycomb body and the outer cylinder were resistance welded in the same manner as in Example 1. The test conditions were the same as in Example 1, and good results were obtained with no abnormalities in the 300-hour durability test.

(Effects of the Invention) As explained above, the metal carrier of the present invention enables online production of joining and winding, which is extremely efficient, and the carrier itself has a flexible structure. It has a structure that can alleviate thermal stress while providing sufficient joint strength in both radial directions, and is highly durable and of extremely high industrial value.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams of the manufacture of a carrier by spot welding according to the present invention, FIG. 3 is a cross-sectional view of the joint of FIG. 1, FIG. 4 is a partial cross-sectional view of the honeycomb body of the present invention, and FIG. 7 to 7 are explanatory diagrams of embodiments of the present invention, and FIG. 8(a). (b) is
An explanatory diagram of another embodiment of the present invention, FIG. 9 is another explanatory diagram when the short laminated foil of the present invention is used. 1...Flat foil 2...Narrow wave foil 3...
・Space part 4...Electrode 7...Honeycomb body 8...External agent Patent attorney Hiroaki Tamura 16 Figure 2 Figure 5 Figure 3 Figure 4 Figure 8 (f2) Figure 6 Figure τFigure 9

Claims (1)

[Claims] 1) In a honeycomb body formed by overlapping a flat foil and a corrugated foil and laminating or winding them, a corrugated foil having a width smaller than that of the flat foil is arranged and bonded to the surface of the flat foil. Into the formed space where no corrugated foil exists, a narrow corrugated foil having the same width as the space, which is joined to a position corresponding to the space on the surface of the opposing flat foil, is fitted, and alternate corrugated foils are nested. A metal carrier having a honeycomb shape characterized by being combined into a shape. 2) A corrugated foil having approximately the same position and the same width as the space is disposed and bonded to the opposite surface of the space formed on the flat foil surface where no corrugated foil exists. A metal carrier with a honeycomb shape.