JPH04194313A - Catalytic converter - Google Patents

Abstract

PURPOSE:To sufficiently secure the bonding strength between a catalyst container and a honeycomb carrier by providing the honeycomb carrier to the catalyst container such that one end of the carrier is secured to the container and the other end thereof is displaceable in the axial direction. CONSTITUTION:A honeycomb carrier 5 has a corrugated-plate like metal foil and a flat-plate like metal foil which are volutely wound around a core in a mutually superposed manner, and between which a number of fine passages are defined. A catalytic metal is coated on the metal foil so as to purify the exhaust gas passing through the fine passages. Since the honeycomb carrier 5 has its rear end secured to a catalyst container 4 via a ring 8 and since the outer periphery and front-end ring 7 thereof define a clearance with respect to the catalyst container 4, the difference between the thermal expansion coefficients of the two members is absorbed. By this arrangement, the bonding strength between the container 4 and the carrier 5 can be sufficiently secured and the metal foils of the carrier 5 can be prevented from being deformed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a catalytic converter device provided in an engine exhaust system.

(Prior Art) For example, as one of the catalytic converter devices installed in the middle of the exhaust pipe to prevent exhaust gas from automobile ennons, etc., the one disclosed in Japanese Patent Application Laid-Open No. 48-54312 is as follows.
A metal honeycomb carrier is formed by spirally winding corrugated stainless steel foil, and numerous narrow channels are defined between the whistles.
The catalyst supported on the foil reduces HC, CO, etc. in the hydration bath.

(Problem to be Solved by the Invention) However, in such conventional devices, the honeycomb carrier is housed in a catalyst container inserted in the middle of the exhaust pipe, and the catalyst container is cooled by outside air. Since the honeycomb carrier is heated by the high-temperature exhaust bus and reaches a high temperature due to the heat of the catalytic reaction, a difference in thermal expansion occurs between the catalyst container and the honeycomb carrier, making it difficult to ensure sufficient bonding strength between the catalyst container and the honeycomb carrier. The problem was that it was difficult.

The present invention aims to solve these conventional problems.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a catalyst comprising a honeycomb carrier in which a corrugated metal foil is spirally wound and a catalyst is supported on the surface of the metal foil. In the converter device, one end of the honeycomb carrier was fixed to a cylindrical catalyst container housing the honeycomb carrier, and the other end was supported so as to be movable in the ring direction.

(Function) During engine operation, the catalyst container is cooled by the outside air, while the honeycomb carrier is heated by the high-temperature exhaust gas and reaches a high temperature due to the heat of the catalytic reaction, resulting in a difference in thermal expansion between the catalyst container and the honeycomb carrier. However, although one end of the honeycomb carrier was fixed to the catalyst container, its t
Since the jlI is provided so as to be displaceable in the axial direction, the difference in thermal expansion of the honeycomb carrier can be absorbed.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, a catalyst humperter device 1 is interposed in the middle of an exhaust pipe and has an exhaust port 2 and a wandering outlet 3.
The catalyst container 4 is composed of a catalyst container 4 having a cylindrical honeycomb carrier 5 and a cylindrical honeycomb carrier 5 housed within the catalyst container 4.

The honeycomb carrier 5 is made of a corrugated metal foil and a flat metal foil that are superimposed on each other and wound in a spiral shape, and a large number of narrow passages are defined between each metal foil. The metal foil is coated with a catalytic metal to purify the exhaust gas that passes through the narrow passages.

As shown in FIGS. 3 and 4, an annular ring 7.8 is fitted to the rear end of the spirally wound metal foil, and each metal foil and each ring 7.8 The space between them is fixed to each other by brazing with NI or the like in the range shown by the two-dot chain line in FIG.

The catalyst container 4 is formed by joining two half-shaped cases 13 and 14 to each other, and each case 13 and 14 has seven run parts 13a and 14a that are joined to each other.
After the honeycomb carrier 5 is housed in the honeycomb carrier 14, the seven run portions 13m and 14a are fixed by welding. 7 ranno 1 each
Seven runs 19 are formed at the front and rear ends of the 3m and 14m lengths.

Each case 13, 14 is formed with an annular recess 15 that joins to the ring 8 at the rear end, and a pair of holes 16 are formed in the center of each case 13, 14, and the opening edge of each case 16 and the ring A welding portion 17 is provided to secure the parts 8 and 8 to each other.

Each case 13, 14 is provided with a predetermined gap 6 along the outer periphery of the honeycomb carrier 5, and an annular recess 18 having a gap of about 51 in the front and rear with respect to the ring 7 at the front end.
is formed, and the difference in thermal expansion between the catalyst container 4 and the honeycomb carrier 5 (
axial displacement).

Next, the effect will be explained.

In the catalytic converter device 1, exhaust gas flowing from the air inlet 2 flows into each narrow passage of the honeycomb carrier 5, and the catalyst coated on the honeycomb carrier 5 converts H in the exhaust gas.
C, CO* are reduced.

While the catalyst container 4 is cooled by the external gas, the honeycomb carrier 5 is heated by the high temperature *** gas.
Since the temperature becomes high due to the heat of the catalytic reaction, a difference in thermal expansion occurs between the catalyst container 4 and the honeycomb carrier 5. However, while the rear end of the honeycomb carrier 5 is fixed to the catalyst container 4 via the ring 8,
Since the ring 7 on the outer periphery and the front end has a gap with respect to the catalyst container 4, this difference in thermal expansion is absorbed, and sufficient bonding strength between the catalyst container 4 and the honeycomb carrier 51111 can be ensured. This can prevent the metal foil from deforming.

Next, in the embodiment of the pond shown in FIGS. 5 and 6, a winding core 32 of T'v: shape is provided on the honeycomb carrier 31, and this winding!
The honeycomb carrier 31 is fixed to the catalyst container 40 through one core 32.

As shown in FIG. 7, the T-shaped winding core 32 has a metal 1
It is formed into a plate shape having a core portion 33 around which the i11 is wound, and a support column portion 34 that extends perpendicularly to the core portion 33.

As shown in FIGS. 8, 9, and 10, an annular ring 37 is attached to the front and rear ends of the spirally wound metal foil 11.
38 are respectively fitted, and each metal M11 and each ring 37.
38 and the winding core 32 are fixed to each other by brazing with Ni or the like in the range shown by the two-dot chain line in FIG.

In this case, each metal foil 11 is fixed at its rear end to the support column 33 of the winding core 32, thereby reliably preventing displacement in the axial direction.

The catalyst container 40 is formed by being divided into two cow-shaped cases 43 and 44, and each case 43 and 44 has seven flange portions 43 at 44 a that connect to each other.
After the honeycomb carrier 31 is placed inside, each 7 runno 11
43m and 44g are fixed by welding. 7 lunges each 4
3m, 44af) Attachment runs 49 are formed at the front and rear ends.

Both ends 35 of the support column 34 of the winding core 32 protrude from the ring 38 in the radial direction, and these protruding ends 35 are connected to the cases 43, 4.
The winding core 3 is sandwiched between the 7 langes 43a and 44a of 4.
2 and the cases 43 and 44 are fixed to each other by a welding portion 50.
will be provided.

In this case as well, each case 43, 44 has a ring 38 at the rear end.
An annular recess 45 is formed which joins the annular enclosure 84.
A pair of holes 46 are formed in the center of each hole 5, and a weld g is formed to fix the opening edge of each hole 46 and the ring 38 to each other.
47 are provided.

Each case 43, 44 is provided with a predetermined gap 6 along the outer periphery of the honeycomb carrier 31, and a ring 47 at the front end.
An annular recess 48 having a gap of about 5 m+s at the front and rear is formed between the catalyst container 40 and the honeycomb carrier 31.
It is designed to absorb the difference in thermal expansion.

In this case, the rear end of the honeycomb carrier 31 is fixed to the catalyst container 40 via the winding core 32 and the ring 38, while the ring 37 at the front end of the outer periphery has a gap with respect to the catalyst container 40. This difference in thermal expansion can be absorbed and sufficient bonding strength between the catalyst container 40 and the honeycomb carrier 31 can be ensured.

By fixing the T-shaped winding core 32 to the end of the spirally wound metal [11], it is possible to effectively prevent the metal M11 from shifting in the axial direction.

(Effects of the Invention) As described above, according to the present invention, in the catalytic converter device, one end of the honeycomb carrier is fixed to the catalyst container, and the other end is provided so as to be displaceable in the axial direction. The thermal expansion difference is allowed to be 1 F, and even if the wandering temperature of ennon increases, the bonding strength between the contact VL container and the honeycomb carrier can be ensured sufficiently.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a catalytic converter device showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line A-A in the figure, vJ3
The figure is a front view of the honeycomb carrier, and Figure 4 is the same figure B-Bl! FIG. Fig. 5 is a longitudinal sectional view of a catalytic converter device showing another embodiment, Fig. 6 is a transverse sectional view taken along the line A-A in the same figure, Fig. 7 is a perspective view showing the manufacturing of a honeycomb carrier, and Fig. 8 9 are front views of the honeycomb carrier, and FIG. 10 is a longitudinal cross-sectional view taken along the line BB in FIG. 9. 1... Catalytic converter device, 4... Catalyst container, 5...
...Honeycomb carrier, 7.8...Ring, 13.14.
- Case, 15, 18... Annular recess, 31... Winding core. Figure 3 Figure 4

Claims (1)

[Claims] A corrugated metal flute is wound in a spiral shape, and a catalyst is supported on the surface of this metal foil to form a honeycomb carrier.
A catalytic converter device characterized in that one end of the honeycomb carrier is fixed to a cylindrical catalyst container housing the honeycomb carrier, and the other end is supported so as to be displaceable in the axial direction.