JPS6024899Y2 - Catalytic converter mounting structure - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an attachment structure for a catalytic converter (commonly known as a manifold converter) which is attached to a position immediately adjacent to the exhaust gas outlet of an exhaust manifold to remove nitrogen oxides and the like from exhaust gas.

FIG. 1 is a half-sectional view showing an example of this type of catalytic converter. This catalytic converter A allows the high-temperature exhaust gas discharged from the exhaust manifold to flow through the catalyst in this high-temperature state. It has good purification efficiency and has recently been attracting attention.

This catalytic converter A has a cylindrical converter container 1, and a catalyst 4 supported by a buffer material 2 and a seal material 3 for preventing gas leakage is housed in the converter container 1.

On the other hand, on the exhaust manifold side, a mouth flange 6 is formed at the mouth of the exhaust gas outlet 5, and the mouth flange 6 and the converter container 1 are connected using a plurality of bolts 7 and nuts 8. I'm trying to install it.

However, since the plate material constituting the converter container 1 described above is formed from a relatively thin plate material, a wide-shaped flange corresponding to the flange portion 6 is machined on the edge of the exhaust manifold side of the converter container 1. In terms of strength, it is impossible to directly attach this thin flange to the flange portion 6 of the exhaust manifold using bolts and nuts.

For this reason, conventionally, a thick and strong flange 9 is fixed to the exhaust manifold side end of the converter container 1 by welding or the like, and this flange 9 and the mouth flange portion 6 are connected via a packing 10 to the bolts. It is connected by 7 etc.

However, when the flange 9 is welded to the converter container 1, the heat generated during welding causes distortion in the flange 9, which deteriorates the accuracy of the contact surface between the lip flange portion 6 and the flange 9. It is necessary to machine the joint surfaces to achieve flatness, which is disadvantageous in terms of cost.

In addition, when installing a catalytic converter, a technique that does not have such problems as in the conventional example is disclosed in Japanese Patent Application Laid-Open No. 53-141166.
It is disclosed in the publication No.

Such technology involves installing a cassette-shaped converter container containing a honeycomb catalyst in an exhaust pipe, fixing the position of the converter container by partially reducing the diameter of the exhaust pipe, and then fixing the position of the converter container by partially reducing the diameter of the exhaust pipe. It is installed at the joint between exhaust pipes or at the joint with the exhaust manifold.

However, when installing, a wide flange is formed at the end of the exhaust pipe that corresponds to the flange provided on the exhaust manifold.Both flanges at the waist are attached using bolts and nuts.As with the problem mentioned above, it is difficult to process a wide flange, and it also increases the strength of the flange. The problem is that it is unreasonable.

Furthermore, since a separate cassette is used, it is disadvantageous in terms of cost.

Utility Model Publication No. 51-3138 describes the above-mentioned flange 9.
Instead of directly fixing the member corresponding to the flange to the pipe by welding or the like, the member corresponding to the flange is welded to the connecting pipe for the collar, which has a ring-shaped collar that is tightened by contacting the member.After the collar portion is brought into contact with the adherend, Disclosure 1 discloses a pipe joint that abuts a flange-equivalent member on the back surface and is tightened with bolts and nuts.

However, this does not mean that work such as welding is completely abolished, and even if the surface accuracy of the flange-equivalent member is achieved, there is a risk that the sealing performance will be impaired due to thermal distortion caused by welding on the connecting pipe with a ring-shaped collar. It is undeniable that there is.

Furthermore, this example also has a separate member called a connecting pipe, which increases the cost.

Japanese Utility Model Publication No. 51-64 discloses that each end of a pair of pipes to be joined is provided with a sleeve that fits on the inner and outer peripheral surfaces thereof, and a flange portion is formed at the end of this sleeve. A joint is shown in which the flanges protruding from each pipe are clamped by a pair of flange members and tightened with bolts.

However, this technique is for attaching polyethylene pipes, and since attaching the sleeve to the pipe can be done relatively easily by taking advantage of the ease of softening and elasticity of polyethylene, it cannot be applied to metal pipes. case has similar problems to the previous example since it requires welding operations.

In addition, the structure in which flanges formed on thin sleeves are brought into contact with each other and tightened by flanges is fine for connections that do not require high strength, such as connecting polyethylene pipes, but A thick flange must be used for a mounting part that requires strength, such as a converter, which is undesirable.

Furthermore, this example also requires a separate member called a sleeve, which increases the cost.

The object of the present invention is to eliminate the drawbacks of the conventional ones described above, and to provide a mounting structure for a catalytic converter that can be easily installed at low cost and with a simple structure without using fixing means such as welding. It is something.

In order to achieve this objective, the present invention provides a catalytic converter in which a converter container having a catalyst therein is attached to the exhaust gas outlet of the exhaust manifold with bolts and nuts. A groove-shaped flange whose end is bent backward in the axial direction of the converter container to form a folded protrusion is integrally formed on the side mouth edge, and this flange is connected to the exhaust gas outlet through a packing. A ring having a predetermined rigidity and having a U-shaped cross section and an outer protruding edge and an inner protruding edge is fitted onto the flange, and the inner protruding edge of this ring is fitted onto the flange. The invention is characterized in that the bolts and nuts are tightened by the bolts and nuts.

The present invention will be explained below with reference to an embodiment shown in FIG.

Note that the same components as those of the conventional device described above are denoted by the same reference numerals in the drawings, and the explanation thereof will be omitted.

A catalytic converter M shown in FIG. 2 has a converter container 1, and a flange 12 is integrally formed at the end of the converter container 1 on the exhaust manifold side.

The flange 12 has a groove shape with an end bent rearward in the axial direction of the converter container 1 to form a folded protrusion 13 .

On the other hand, a ring 14 is loosely fitted into the curved surface of the converter container 1.

This ring 14 has an outer protruding line 15 and an inner protruding edge 1
It has a U-shaped cross section and is formed by press working, and has a wall thickness that corresponds to the strength required for mounting the catalytic converter, and has a predetermined rigidity as a whole.

The inner protruding edge 16 can come into contact with the flange 12 of the converter container 11.

The ring 14 is also provided with a plurality of through holes 18 coaxial with the screw holes 17 of the mouth flange portion 6 of the exhaust gas outlet portion 5 .

Next, the tightening action will be explained.

First, on the exhaust manifold side, the bolts 7 are screwed into the screw holes 17 of the mouth flange portion 6, respectively.

Next, the converter container 1 is brought into contact with the exhaust manifold so that the gasket 10 is sandwiched between the mouth flange portion 6 and the flange 12 of the converter container 1.

While maintaining this state, the through hole 15 of the ring 14 is inserted into the bolt 7 and the nut 8 is tightened.

The tightening action by this ring 14 will be explained in more detail.

As the aforementioned nut 8 is tightened, the inner protruding edge 16 of the ring 14 will tighten the flange 12 of the converter container 1.
Pressure is applied toward the mouth flange portion 6 side of the exhaust manifold.

In this case, the ring 14 has a U-shaped cross section and a predetermined wall thickness, so it has high rigidity, and there is a risk that it will deform when the nut 8 is tightened, or that this deformation will cause so-called uneven contact. Instead, the flange 12 is pressurized almost uniformly over its entire circumference.

Moreover, since the inner protruding edge 16 of the ring 14 pressurizes the flange 12 of the converter container 1 during this tightening,
The contact area between the ring 14 and the flange 12 during pressurization is small, and the tightening force per unit area is large.

Therefore, sufficient adhesion can be obtained even with a small tightening force,
This means that gas leakage can be reliably prevented.

Furthermore, since the ring 14 is press-formed to have a U-shaped cross section, it has a reinforced structure, and the weight of the ring 14 can be reduced compared to a thick plate like the conventional flange 9 shown in FIG. Furthermore, since there is no need to weld the converter container 1 and the ring 14, the welding process can be omitted, and thermal deformation etc. that occur during this welding process can be avoided, and machining to achieve surface accuracy as described above is not required. Can be done.

Therefore, it is advantageous in terms of cost. In addition, since the catalytic converter M installed as described above is installed on the edge flange 6 provided on the outer periphery of the exhaust gas outlet section 5, it passes through the exhaust manifold and from the exhaust gas outlet section 5. The discharged exhaust gas flows smoothly into the catalyst 4, and the flow resistance does not increase unnecessarily.

As explained above, the mounting structure of the catalytic converter according to the present invention has a flange integrally formed on the converter container, and the flange has an inner protruding edge of a ring having a U-shaped cross section and a predetermined rigidity. Since it is attached to the mouth edge flange of the exhaust gas outlet of the exhaust manifold using bolts and nuts, it is easy to install and does not require welding, so there is no inconvenience caused by welding.
Furthermore, since the ring has a 3-shaped cross section, the wall thickness can be made thinner than conventional flanges.

Furthermore, the number of parts is considerably increased, unnecessary machining is eliminated, and it is advantageous in terms of cost.

[Brief explanation of the drawing]

FIG. 1 is a half longitudinal sectional view showing a conventional catalytic converter mounting structure, and FIG. 2 is a half sectional view showing a catalytic converter mounting structure according to the present invention. 1...Converter container, 4...Catalyst,
5... Exhaust gas outlet section, 6... Mouth flange section, 7... Bolt, 8... Nut, 10... Gasket , 12...Flange, 14...Ring, M...Catalytic converter.

Claims (1)

[Scope of utility model registration request] A catalyst 4 is installed inside the exhaust gas outlet part 5 of the exhaust manifold.
Converter container 1 provided with bolts 7 and nuts 8
In the catalytic converter which is installed by
A groove-shaped flange 12 whose end portion is bent rearward in the axial direction of the converter container 1 and has a folded protrusion 13 is integrally formed, and this flange 12 is connected to the exhaust gas outlet portion 5 through a packing 10. comes into contact with the mouth flange portion 6 of the
A ring 14 having a predetermined rigidity and having a U-shaped cross section and an outer protruding edge 15 and an inner protruding edge 16 is attached to the flange 12, and the inner protruding edge 16 of the ring 14 is fitted onto the flange 12 to tighten the bolt. A mounting structure for a catalytic converter that is tightened using nuts 7 and 8.