JPH1113467A - Catalyst converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the mouth opening of a core caused by the isolation between catalyst carriers by the flow-in pressure of exhaust gas by forming a honeycomb core by overlapping the catalyst carriers made of metallic thin plates formed in an undulated shapes and forming a notched groove in the end part of the entrance side of the core so as to engage a connecting piece. SOLUTION: A catalyst converter 1 includes a metallic outer cylinder 2 and a honeycomb core 3, and the core 3 is composed of a catalyst carrier 5 where a stainless metallic thin plate for carrying a catalyst on the surface is formed in an undulated form shape. In this case, in the center position of the end part of the entrance side of the core 3, one line of a notched groove 6 is formed to have required width and depth in the overlapping direction of the catalyst carriers 5, i.e., in the long-diameter direction of the core 3 formed to have a long circular front surface. In both sides of the notched groove 6, a connecting piece is formed where the notched end of each catalyst carrier 5 is bent in one direction along the notched groove 6, a series of side walls 7 is formed by overlapping and connecting the connecting pieces and, by the side walls 7, the dissociation between the catalyst carriers 5 adjacent to each other is constrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalytic converter provided in an exhaust system or the like of an automobile and purifying harmful components in the exhaust gas through a catalytic reaction by passing the exhaust gas.

[0002]

2. Description of the Related Art In a catalytic converter, for example, as shown in Japanese Patent Application Laid-Open No. 6-393, the overlapped catalyst carriers are separated by the inflow pressure of exhaust gas and the core is opened. In order to prevent this, there is known a method in which a recess is formed at the end of the core in the direction in which the catalyst carrier is overlapped, and a metal coupling member is inserted into the recess, joined and fixed. .

[0003]

Since a metal connecting member is inserted into and joined to the recess formed at the end of the core, the cell is closed at the portion where the connecting member is disposed. It is undeniable that the exhaust gas flow is impaired and the exhaust gas purification performance is affected accordingly.

Accordingly, the present invention can prevent the core from opening without impairing the exhaust gas flow of the core,
An object of the present invention is to provide a catalytic converter capable of further improving exhaust gas purification performance.

[0005]

According to the first aspect of the present invention, a catalyst carrier formed of a corrugated metal sheet is superposed on the catalyst carrier.
In a structure in which a honeycomb-shaped core in which cells are formed in the overlapping portion is formed, and this core is disposed in the outer cylinder, a notch groove is formed at the end of the core on the inlet side in the overlapping direction of the catalyst carrier. A notch edge of each catalyst carrier is formed on both side edges of the notch groove by superimposing and connecting connection pieces bent in one direction along the notch groove to form a series of side walls. The separation between the catalyst carriers is restricted by the side walls.

According to a second aspect of the present invention, the core according to the first aspect is configured such that one catalyst carrier is continuously folded in an S-shape in a waveform direction and overlapped in a honeycomb shape. I have.

According to a third aspect of the present invention, the catalyst carrier according to the first and second aspects is formed by cutting the ridge of the corrugation in the opposite direction from a middle position of the inclined wall forming the ridge and the valley of the corrugation. While a plurality of raised and raised valleys are provided in the direction of the fold of the waveform, the valleys of the waveform are formed with raised and raised ridges formed by being raised and raised in the opposite direction from the middle position of the inclined wall. It is characterized in that a plurality of folds are provided in the fold direction of the waveform.

According to a fourth aspect of the present invention, the cut-and-raised valley and the cut-and-raised ridge according to the third aspect are formed from a center position of the inclined wall forming the corrugated peak and the valley of the catalyst carrier. It is characterized by being cut and raised.

According to a fifth aspect of the present invention, a shelf portion is formed at the center of the inclined wall that forms the peaks and valleys of the waveform of the catalyst carrier according to the third aspect of the invention along the fold direction of the waveform. The cut and raised valley formed at the peak of the waveform and the cut and raised valley formed at the valley of the waveform adjacent to the peak of the waveform are formed by cutting and raising at the shelf. The width of the shelf portion is set in the waveform direction between the cut and raised toes of the adjacent cut and raised valley portion and the cut and raised ridge portion.

According to a sixth aspect of the present invention, the cut and raised valley formed on the corrugated valley of the catalyst carrier and the cut and raised valley formed on the corrugated valley of the catalyst carrier according to the third to fifth aspects. It is characterized in that it is formed offset in the fold direction of the waveform, and a required interval is set in the fold direction of the waveform between the cut and raised toes of the adjacent cut and raised valley and the cut and raised ridge. And

[0011]

According to the first aspect of the present invention, the notch grooves formed on the inlet end of the core in the direction in which the catalyst carriers are overlapped are bent to the notch edges of the respective catalyst carriers. The connected pieces are superimposed and connected to form a series of side walls,
Since the side walls restrict the separation of the superposed catalyst carriers from each other, the opening of the catalyst carriers from each other due to the inflow pressure of the exhaust gas at the inlet side of the core can be prevented. Thus, the exhaust gas purification performance can be further improved by eliminating the deformation of the honeycomb shape in which the cells are assembled.

In addition, in the portion where the cutout groove is formed in the core, the connecting piece at the cutout edge of each catalyst carrier is bent in the direction in which the catalyst carriers are overlapped to form a side wall, and the side wall closes the cell. Therefore, the exhaust gas purifying performance can be improved without hindering the exhaust gas flowability of the core.

According to the second aspect, in addition to the effect of the first aspect, a single catalyst carrier is continuously folded back in an S-shape in a waveform direction, and the catalyst carrier is overlapped in a honeycomb shape to constitute a core. Therefore, the core can be easily configured, and the film-out phenomenon in which the catalyst carrier jumps backward due to the inflow pressure of the exhaust gas can be prevented.

According to the third aspect, in addition to the effects of the first and second aspects, in addition to the effects of the first and second aspects, the catalyst carrier has a plurality of cut-and-raised valleys formed by cutting and raising in the crests of the waveform in the reverse direction. In addition to the above, the valleys of the corrugations are provided with a plurality of ridges which are formed by being raised and raised in the opposite direction in the direction of the fold of the corrugations, so that the catalyst carrier which is overlapped at these ridges is formed. Exhaust gas can be caused to flow between the cells formed between each other, and in addition to being able to sufficiently contact the exhaust gas with the catalyst on the surface of the catalyst carrier to activate the catalytic reaction,
Due to the presence of the cut and raised valley and the cut and raised ridge, the adjacent catalyst carriers can be prevented from contacting each other and cells can be secured,
Exhaust gas purification performance can be improved.

Further, since the exhaust gas can be circulated between the cells formed between the superposed catalyst carriers, the pressure distribution of the exhaust gas can be made substantially uniform as a whole, and the Durability can also be improved.

Further, by forming the cut and raised valleys and the cut and raised ridges, the rigidity of the catalyst carrier can be increased.

According to the fourth aspect, in addition to the effect of the third aspect, in addition to the effect of the third aspect, the cut and raised valley and the cut and raised ridge are formed at the center of the slope wall forming the corrugated peak and the valley of the catalyst carrier. Since the cut and raised portion is formed from the position, the cut and raised opening area of the cut and raised valley portion and the cut and raised portion can be increased, and the flow of exhaust gas between cells can be improved. it can.

Further, it is possible to make the crests and ridges of the catalyst carrier and the ridges and valleys and the valleys of the waveform have the same amount of protrusion, so that the adhesion of the catalyst carriers to each other is reliably prevented. Can be.

According to the fifth aspect, in addition to the effect of the third aspect, in addition to the effect of the third aspect, the cut and raised valley and the cut and raised ridge are formed at the center of the inclined wall forming the corrugated peak and the valley of the catalyst carrier. Since it is cut and raised with the shelf formed at the position as a boundary, the cut and raised opening area of these cut and raised valleys and cut and raised ridges can be increased,
Exhaust gas flow between the cells can be improved.

In addition to the fact that the peaks and the raised valleys of the catalyst carrier and the valleys and the raised and raised valleys of the waveform can be made to have the same protrusion amount, it is possible to prevent the catalyst carriers from sticking to each other. When the catalyst carriers are displaced from each other in the waveform direction, it is ensured that the corrugated peaks or the cut and raised valleys, or the valleys or the cut and raised valleys of the corrugated bumps abut on the shelf, so that the catalyst carriers are in close contact with each other. And a cell can be secured.

Furthermore, a gap between the widths of the ledges in the corrugated direction is secured between the cut and raised toes of the adjacent cut and raised valleys and the cut and raised ridges. It is possible to avoid tearing between the cut and raised toes.

According to the sixth aspect, in addition to the effects of the third to fifth aspects, a required space is provided between the cut and raised toes of the cut and raised valley and the cut and raised ridge in the direction of the fold of the waveform. Since the interval is set, it is possible to reliably avoid the gap between the cut-and-raised toe due to the difference in the coefficient of thermal expansion.

[0023]

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

1 to 3, reference numeral 1 denotes a catalytic converter, which includes a metal outer cylinder 2 formed in an oval cross section (including an elliptical shape) and a honeycomb core 3 disposed in the outer cylinder 2. It has.

The diffusers 4 at both ends of the outer cylinder 2 are formed separately, and these diffusers 4 and 4 are fitted and fixed in both ends of the outer cylinder 2.

Reference numeral 5 denotes a catalyst carrier constituting the core 3, which is formed into a corrugated shape with a thin metal plate such as stainless steel having a catalyst supported on the surface thereof. Although the cells are continuously folded in a letter shape and overlapped in a honeycomb shape to form cells in each overlapped portion, a plurality of catalyst carriers 5 may be stacked to form a honeycomb-shaped core 3. .

In the center position of the end of the core 3 on the inlet side, the required width and depth are set in the direction in which the catalyst carriers 5 are superposed, that is, in the major axis direction of the core 3 formed in the front oval shape in this embodiment. One notch groove 6 is formed, and the notch edge of each catalyst carrier 5 is bent in one direction along the notch groove 6 on both side edges of the notch groove 6. Connection pieces 6a, 6a
Are connected to each other to form a series of side walls 7, and the side walls 7 restrain the adjacent catalyst carriers 5 from being separated from each other.

For example, as shown in FIG. 4, a notch 8 is formed in each catalyst carrier 5 from the side of the core 3 by a laser beam or the like in the above-mentioned notch groove 6 and connecting piece 6a.
The vertical cut is pushed open by a jig (not shown) having a barbed tip, for example, and the connection piece 6a is opened at the folding line position indicated by the broken line.
Is bent, a notch groove 6 is formed as shown in FIG. 3, and the adjacent connecting pieces 6a, 6a are overlapped with each other. Therefore, these connecting pieces 6a, 6a are welded or welded. The side wall 7 is joined by brazing or the like.
Can be configured.

The catalyst carrier 5 shown in FIGS. 5, 6 or 7 to 9 is used.

The catalyst carrier 5 shown in these figures is formed by cutting and raising in the opposite direction from the middle of the inclined wall 5c which forms the wave-shaped peak 5a and the valley 5b on the wave-shaped peak 5a. While a plurality of cut-and-raised valleys 5d are provided in the direction of the fold of the waveform, the valley 5b of the waveform has a cut-and-raised ridge 5e formed by being raised and raised in the opposite direction from an intermediate position of the inclined wall 5c. A plurality is provided in the fold direction of the waveform.

Here, in the catalyst carrier 5 shown in FIGS. 5 to 7, a ledge 5f is formed at the center of each of the sloping walls 5c of the corrugation along the fold direction of the corrugation, and each of the adjacent peaks is formed. Part 5a
The cut-and-raised valley portion 5d formed in the valley portion 5b and the cut-and-raised ridge portion 5e formed in the valley portion 5b are cut and raised with the shelf portion 5f as a boundary, and cut with the adjacent cut-and-raised valley portion 5d. between the cut-and-raised toe of raised ridges 5e is set apart S ₁ of the width of the shelf portion 5f in the waveform direction.

In the examples shown in FIGS. 5 and 6, the peak 5a of the waveform
The cut-and-raised crest portion 5e adjacent to this is formed to have the same length, and is formed regularly with a one-pitch shift in the fold direction of the waveform. In the example shown in FIG. Crest 5a and valley 5b, cut and raised valley 5d, cut and raised ridge 5
e is formed to have the same length, and the adjacent waveform peaks 5a are formed.
The cut-and-raised crests 5e and the adjacent wave-shaped valleys 5b and the cut-and-raised valleys 5d are formed with regularity in a state shifted by one pitch in the fold direction of the waveform. The valley portion 5d and the cut-and-raised ridge portion 5e are formed in such a manner as to be offset in the fold direction of the waveform without such regularity, and the adjacent cut-and-raised valley portion 5d and the cut-and-raised ridge portion 5e are formed. A required interval may be set between the cut-and-raised toe ends in the direction of the fold of the waveform.

The catalyst carrier 5 shown in FIGS. 8 and 9 is formed such that adjacent cut and raised valleys 5d and cut and raised ridges 5e are offset from each other in the fold direction of the corrugation. between each cut-and-raised toe electromotive City valley 5d and-lifted crests 5e, it is set the required interval S ₂ in the fold direction of the waveform.

In the example shown in FIG. 8, the cut and raised valleys 5d and the cut and raised ridges 5e are formed by cutting and raising in the opposite directions from the center position of the corrugated inclined wall 5c. In the example shown in FIG. 5, the cut-and-raised valley 5d is formed shallower than the wave-shaped valley 5b, and the cut-and-raised ridge 5e is formed lower than the wave-shaped valley 5a. and in addition to spacing S ₂ of the fold direction of the aforementioned waveform between the cut-and-lifted toe cut-and-raised ridge portions 5e, are as is required intervals S ₃ in the waveform direction is set.

According to the structure of the above embodiment, normally, the exhaust gas flowing into the catalytic converter 1 from an exhaust pipe (not shown) having a diameter smaller than that of the core 3 is diffused by the diffuser 4 on the inlet side. Although the exhaust gas flows into almost the entire cell on the inlet side, the exhaust gas flowing from the exhaust pipe tends to concentrate on the central portion of the core 3. Tend to separate from each other.

However, as described above, the notch edge of each catalyst carrier 5 is formed on both side edges of the notch groove 6 formed at the center of the end of the core 3 on the inlet side in the direction in which the catalyst carriers 5 overlap. A series of side walls 7 are formed by connecting and connecting the bent connection pieces 6a, 6a to each other, and the side walls 7 restrict the mutual separation of the superposed catalyst carriers 5 of the core 3 from each other. Therefore, it is possible to prevent an opening phenomenon in which the catalyst carriers 5 are separated from each other due to the inflow pressure of the exhaust gas at the inlet side of the core 3, and eliminate the deformation of the honeycomb shape in which a large number of cells are assembled, thereby purifying the exhaust gas. The performance can be further improved.

Moreover, in the portion of the core 3 where the notch groove 6 is formed, the connecting pieces 6a, 6a at the notch edges of each catalyst carrier 5 are bent in the direction in which the catalyst carriers 5 overlap to form the side wall 7. Since the cells are not blocked by the side walls 7, the exhaust gas purifying performance can be improved without impairing the exhaust gas flow of the core 3.

Further, since the core 3 is configured by continuously folding one catalyst carrier 5 in an S-shape in a waveform direction and superimposing it in a honeycomb shape, the catalyst carrier 5 is rearwardly moved by the inflow pressure of the exhaust gas. It is possible to prevent the film-out phenomenon that jumps out to the side.

Particularly, in the present embodiment, as the above-described catalyst carrier 5, a cut-and-raised valley 5d formed by cutting and raising in the opposite direction to the corrugated peak 5a as shown in FIGS. Since a plurality of ridges 5e are formed in the valleys 5b of the waveform in the opposite direction and formed in the direction of the fold of the waveform, the catalyst carriers 5 are superposed.
As shown by arrows in FIG. 5, the exhaust gas can flow between the mutually formed cells. Therefore, the exhaust gas is sufficiently brought into contact with the catalyst on the surface of the catalyst carrier 5 to activate the catalytic reaction. In addition to the above, the presence of the cut and raised valleys 5d and the cut and raised ridges 5e prevents adjacent catalyst carriers 5 from adhering to each other and secures a cell. Purification performance can be further improved.

Further, the catalyst carriers 5 thus superposed are overlapped.
The exhaust gas can be circulated between the cells formed between the cores 3. Therefore, the pressure distribution of the exhaust gas can be made substantially uniform over the entire core 3, and the durability of the core 3 is improved. be able to.

Further, by forming the cut and raised valley portion 5d and the cut and raised ridge portion 5e, the rigidity of the catalyst carrier 5 itself can be increased, and the sense of quality and reliability can be improved.

Here, if the catalyst carrier 5 shown in FIGS. 5 to 7 is used, the cut and raised valley 5d and the cut and raised ridge 5e are connected to the corrugated peak 5a and the valley 5b of the catalyst carrier 5. Since it is formed with the ledge 5f formed at the center position of the sloped wall 5c to be formed as a boundary, the cut and raised valley 5d and the cut and raised ridge 5e can have a larger opening area. As a result, the flow of exhaust gas between the cells can be improved.

Further, the corrugated peaks 5a and the raised ridges 5e and the corrugated valleys 5b and the raised valleys 5d of the catalyst carrier 5 can be made to have the same amount of protrusion, so that the catalyst carriers 5 are in close contact with each other. In addition, when the catalyst carriers 5 are displaced from each other in the waveform direction, a corrugated ridge 5a or a raised ridge 5e, or a corrugated valley 5b or a raised valley is formed on the shelf 5f. 5d abuts and the mutual contact of the catalyst carriers 5 can be reliably avoided to secure cells.

[0044] Furthermore, since the inter-and-lifted toe of adjacent cut and raised to valley 5d and-lifted crests 5e, the spacing S ₁ in the width of the shelf portion 5f in the waveform direction is secured, It is possible to prevent the cut-and-raised toe from being torn due to the difference in thermal expansion coefficient.

When the catalyst carrier 5 shown in FIG. 8 is used,
Of course, the same exhaust purification performance as in the case of using the one shown in FIGS. 5 to 7 is obtained, and between the cut and raised toes of the cut and raised valley 5d and the cut and raised ridge 5e, because have set spacing S ₂ using the fold direction of the waveform, between the cut-and-raised toe by the difference in thermal expansion coefficient in this case it is possible to avoid the tearing.

Further, if the catalyst carrier 5 shown in FIG. 9 is used,
In addition to obtaining substantially the same exhaust gas purifying performance as that shown in FIG. 8, a corrugated fold is formed between the cut and raised toes of the cut and raised valley 5d and the cut and raised ridge 5e. Required spacing S in the direction
_2, because is set the required interval S ₃ to the waveform direction, a tearing between the cut and raised toe due to the difference in thermal expansion coefficient can be reliably avoided.

In the above embodiment, one notch groove 6 is formed at the center of the entrance end of the core 3 so that the core 3 is prevented from opening by the side walls 7 on both side edges. However, it is a matter of course that a plurality of the notched grooves 6 may be provided to prevent the core 3 from opening by the side wall 7 at each groove forming portion.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view taken along line AA of FIG. 2 showing a first embodiment of the present invention.

FIG. 2 is a schematic sectional view showing the entire structure of the embodiment.

FIG. 3 is a schematic perspective view showing a cutout groove forming portion of a core.

FIG. 4 is a side view showing a notch provided in a core in a process before forming a notch groove.

FIG. 5 is a perspective view of a catalyst carrier used in each embodiment.

FIG. 6 is an explanatory view of the catalyst carrier shown in FIG.

FIG. 7 is an explanatory view showing a different example of the catalyst carrier.

FIG. 8 is an explanatory view showing another example of a catalyst carrier.

FIG. 9 is an explanatory view showing a different example of the catalyst carrier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Catalytic converter 2 Outer cylinder 3 Core 5 Catalyst carrier 5a Wave-shaped peak 5b Wave-shaped valley 5c Sloped wall 5d Cut-and-raised valley 5e Cut-and-raised ridge 5f Shelf 6 Notch groove 6a Connection piece 7 Side wall

Claims (6)

[Claims] 1. A structure in which a catalyst carrier made of a corrugated metal sheet is overlapped to form a honeycomb core having cells formed in the overlapped portion, and the core is disposed in an outer cylinder. Notch grooves are formed at the end on the inlet side in the direction in which the catalyst carriers overlap, and the notch edges of each catalyst carrier are bent in one direction along the notch grooves on both side edges of the notch grooves. A catalytic converter characterized in that a series of side walls are formed by superimposing and connecting the connected connection pieces to each other, and the separation of the catalyst carriers is restrained by the side walls. 2. The catalytic converter according to claim 1, wherein the core is formed by continuously folding one catalyst carrier in an S-shape in a waveform direction and overlapping the honeycomb in a honeycomb shape. 3. The catalyst carrier is cut and raised in a reverse direction from a middle position of a slope wall forming a peak and a valley of the waveform at a crest of the waveform, and a cut-and-raised valley formed in a crease direction of the waveform. On the other hand, the valley portion of the waveform is provided with a plurality of cut-and-raised ridges formed in the reverse direction from the middle position of the inclined wall in the fold direction of the waveform. The catalytic converter according to claim 1. 4. The cut-and-raised valley and the cut-and-raised ridge are formed by being cut and raised from a center position of a slope wall forming a wave-shaped ridge and a valley of a catalyst carrier. The catalytic converter according to claim 3. 5. A shelf portion is formed at a center position of a slope wall forming a wave-shaped peak and a valley of the catalyst carrier along a crease direction of the wave, and a cut-and-raised portion formed in the wave-shaped peak is formed. A trough and a cut-and-raised crest formed at a wave-shaped trough adjacent to the wave-shaped crest are cut and raised with the shelf as a boundary, and the adjacent cut and raised trough is cut and raised. 4. The catalytic converter according to claim 3, wherein a gap of a shelf width is set in a waveform direction between the cut and raised toes of the ridge. 6. A cut-and-raised valley formed at a wave-shaped valley of the catalyst carrier and a cut-and-raised ridge formed at a wave-shaped valley are offset from each other in a fold direction of the wave to be adjacent to each other. A required interval is set between the cut and raised toes of the cut and raised valley portion and the cut and raised ridge portion in the fold direction of the waveform.
6. The catalytic converter according to any one of 5.