JPS5884038A - Monolithic catalyst vessel - Google Patents

Abstract

PURPOSE:To ensure to fix a monolithic catalyst carrier in the axial direction, by providing recesses each having a taper becoming small in a pressing direction and a stepped part on the inner circumference of a monolithic catalyst vessel for inserting the carrier. CONSTITUTION:A monolithic catalyst carrier 11 is surrounded with a wire net 16 and pressed into a monolithic catalyst vessel 14. Recesses 18 each having a taper 18a becoming smaller in the pressing direction and a step 18b are provided on the inner circumference of the vessel 14 of the part A for inserting the carrier 11, or protuberances are provided in place of them. Since the net 16 is caught with the stepped part 18b, it does not move or slide in the direction reverse to the pressing direction. Sliding in the pressing direction is hindered by the tapers 18a and the stopper action of a circular buffer member 17. The depth (h) of the step 18b is preferably >=1/2 the outside diameter of the wires for constituting the net 16 in order to stop sliding of the net 16 in the direction reverse to the pressing direction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a container for a monolithic catalyst used in an exhaust gas purification device for automobiles.

Conventionally, catalytic converters using various types of ceramic monolithic catalyst carriers have been widely used as exhaust gas purification devices for automobiles, but the monolithic catalyst carriers tend to slide relative to each other within the monolithic catalyst container due to the vibrations of the automobile engine and vehicle. The problem is that the paper is easily damaged due to partial chipping or cracking during use due to exposure to vibration.

A number of suggestions have been made about Shita-ryoku as a measure to prevent damage to ceramic monolithic catalyst carriers.

A typical method is to insert a wire net made of heat-resistant steel wires having spring characteristics between the inner surface of the monolith catalyst container and the monolith catalyst carrier into the monolith catalyst container. The method of press-fitting the monolithic catalyst carrier together with the wire net is the most widely adopted method. In this method, the holding force in the radial direction between the monolithic catalyst container and the monolithic catalyst carrier is sufficiently guaranteed, but in the axial direction, there is a gap between the wire net and the monolithic catalyst carrier on the outer skin surface of the wrinkled carrier. Although slipping does not occur due to the unevenness and frictional resistance, there is a problem in that slipping is likely to occur between the wire net and the monolithic catalyst container.

As a countermeasure to this problem, the following measures have been taken.

That is, as a first example, as shown in FIG.
．． Insert bolt 4 with a sharp tip (on the outside of case 3) into wire net 2).

Fix the wire net 2 by tightening the screws.

9. As a second example, as shown in FIG. 1, the same assembly as in the first example is carried out, and after that, the wire net 2 and the case 5 are assembled in the hole previously provided on the side of the case 3. There is a part that fixes the wire net 2 by performing plug welding to integrate the wire net 2. In the figure, the part indicated by the reference numeral 5 is a welded part.

Furthermore, as a third example, as shown in FIG.
When assembling the case 3 in the same manner as in the example, when attaching and tightening the case 3 to the exhaust manifold 6, there is a cushioning material such as a cushion 7 that is inserted and tightened to fix the wire net 2.

As mentioned above, methods have been taken to prevent damage to the monolithic catalyst carrier due to relative slippage in the axial direction or vibration by using one or a combination of two or more of the various methods, but in terms of case durability and reliability, Not enough friends.

That is, in the first example, there is a low probability that the bolt tip will fit securely between the wire nets, and since it is locally fixed by the small diameter tip, the holding force is small, so multiple fixing points are required. However, there were problems in that the reliability was poor. 9. In the second example above, the reliability of welding is low because the wire net that is one of the welding partners is a small diameter wire, and the plug S* hole part is also 1Ils degree due to welding technology if it is a cast case. In any case, there are many problems such as high welding and a large number of welding locations.Furthermore, in the third example, the axial dimensions of the ceramic monolithic catalyst carrier vary greatly.

For this reason, there is a large variation in the holding force of the cushioning material, and when the O-axis dimension of the monolithic carrier is large, chips and cracks may occur due to excessive load on the carrier during assembly 1. 9. When the shaft dimension is small, the presser foot holding force is small and 1.
However, there was a problem in that the inner surface of the case and the monolithic catalyst carrier with the wire net interposed therein were likely to slip, and in any case, reliability was poor.

The present invention has been made in view of the above-mentioned problems in the prior art.It is an object of the present invention to provide a container for a monolithic catalyst that has a simple structure, is highly reliable, and can reliably fix a monolithic catalyst carrier in the axial direction. The purpose is to

For this reason, the structure of the monolith catalyst container of the present invention is such that in the monolith catalyst container in which the monolith catalyst carrier is press-fitted with a wire net interposed therebetween, the inner circumference of the monolith catalyst container, which is the monolith catalyst carrier insertion portion, is It is characterized by having an IJ4 space or protrusion having a tapered part and a stepped part that taper in the press-fitting direction.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 4.

FIGS. 2 and 3 show a first embodiment of the present invention, with FIG. 2 being a sectional view and FIG. 3 being an enlarged sectional view of the main parts.

In FIGS. 2 and 3, 11 is a monolith, 1
2 is the 2 lange part for mounting the exhaust manifold, 13
14 is the monolith catalyst container (hereinafter referred to as the case), 15 is the inner surface of the Fi case, 16 is the flange for mounting the exhaust pipe,
1 is a wire net, 17 is an annular buffer member, and 18Fi tapered portion 181 and a stepped portion 18b are provided. In this embodiment, four pieces are provided. The monolithic catalyst 11 is inserted into the case 14 at the same time from the exhaust manifold side with a wire net 16 wrapped around its outer circumference 1fiK in advance. At this time, the outer diameter of monolith contact #111, the free thickness of wire net 16, and the diameter of case inner surface 15 are set so that the outer diameter of wire net 16 is larger than the diameter of case inner surface 15, and the monolith catalyst The wire net 16 is press-fitted into the gap between the outer diameter of the case 11 and the inner diameter of the case inner surface 15 in a state where it is elastically compressed in the thickness direction.

In this pressure overload 1i, the wire net 16 that has been cut into the inner surface of the case 15 or reached the dragonfly 18 has a step 1i 118b.
The elastic compressive force is released and bulges outward, but after that, the press-fit is performed while being gradually re-compressed along the tapered portion tea that tapers in the press-fit direction. This press-fitting is completed when the lower end surface of the monolithic catalyst 11 reaches the loam-like loose member 17 that has been previously disposed at the bottom of the case 14.

In this way, the wire net 16 housed in the case 14 together with the monolithic catalyst 11 is caught on the stepped portion 18b, so it will not slide in the direction opposite to the press-fitting direction, and the wire net 16 will not slide in the press-fitting direction. 1fla and the stopper function of the annular buffer member 17.

This recess 18 is clearly shown in FIG. 3, and the depth h of the stepped portion 18b, which is the length of the stepped portion, is
In order to reliably prevent the wire net 16 from sliding in the reverse press-fitting direction, it is desirable to increase the outer diameter of the edge material constituting the wire net 16 by 4 or more.

In addition, in this example, four recesses were provided that spanned the entire circumference of the same circumference, but the recess is not limited to this.
An appropriate number may be provided locally, or if provided all around the same circumference, one or more may be provided, or one or more may be provided on the cotton wire in the circumferential direction of the case. This also applies to protrusions instead of recesses, which will be described later.

FIG. 4 is an enlarged view of the main part of the second embodiment, but in this embodiment, a protrusion 1 is used instead of a recess! The inner surface of the case 15
It consists of a tapered part 191 that tapers in the press-fitting direction and a stepped part 19b. The functions and effects of this embodiment are the same as those of the first embodiment, so their explanation will be omitted.

According to the present invention as described above, in a monolithic catalyst container in which a monolithic catalyst carrier is press-fitted with a wire net interposed therebetween, the monolithic catalyst carrier is inserted into the monolithic catalyst carrier insertion portion on the inner circumference of the monolithic catalyst container in the press-fitting direction. Since a recess or protrusion having a tapered groove and a stepped portion can be provided, it is possible to provide a monolithic catalyst container that has a simple structure, is highly reliable, and can reliably fix the monolithic catalyst carrier in the axial direction.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a monolithic catalytic converter showing a conventional embodiment, Fig. 2 is a sectional view showing a first rear embodiment according to the present invention, and Fig. 5 is an enlarged view of the main part of Fig. 2. Sectional view, FIG. 4/Ii is an enlarged sectional view of the main part of the second embodiment. 11... Monolith catalyst 14... Monolith catalyst container 15... Monolith catalyst container inner surface 16... Wire net 18... Recess 18
a...Tapered part 18b...Stepped part 19...
・Protrusion 19a...Tapered part 19b...
Patent applicant for step portion: Toyota Motor Corporation Sai/W!
J Sai 2 Figure I F 3 WJ Iko 4 Procedural Amendment December 17, 1980 Commissioner of the Patent Office - Kokai-dono 1, Indication of Case Patent Application No. 181968 3, 1982;
Relationship with the case of the person making the amendment Name of the patent applicant (32t)) 'jl Yu Jidosha Kogyo Co., Ltd. (and 1 other person) 6. Subject of the amendment l Contents of the amendment (1) Scope of patent claims in the specification i! lVt (see attached sheet) Correct. (2) "Outer diameter" is written in line 11 on page 8 of the specification.
Correct it as "r wire diameter". (3) From line 1815 to line 418 on page 8 of the tomb details, it says, “It may be set up by a friend.” tl. ``Also, this recess may be locally divided into one or more than one recess without extending over the entire circumferential surface of the case.'' (4) In the 10th line of page 1 of the specification, the phrase ``to convey.'' should be amended to ``to tell.'' (Attachment) 2. Claims (1) In a monolithic catalyst container into which a monolithic catalyst carrier is press-fitted with a wire net interposed therebetween, on the inner circumference of the monolithic catalyst container, which is the monolithic catalyst carrier insertion portion. A monolithic catalyst container characterized by nine recesses or protrusions having a tapered part and a stepped part extending forward in the press-fitting direction. (2) The monolithic catalyst container according to claim S, wherein the depth or height of the stepped portion in the cross-sectional shape of the recess or protrusion is at least % of the wire diameter of the wire constituting the wire net. (3) The recess or protrusion extends over the entire circumference of the monolithic catalyst container, and the recess or protrusion extends over the entire circumference of the monolith catalyst container.
The monolithic catalyst container according to claim 1, wherein one or more monolithic catalyst containers are provided. (4) Claim 8111 (I) in which one or more recesses or wedge projections are provided in a spiral shape on the circumferential surface of the monolithic catalyst container! Container for O monolith catalyst.

Claims (4)

[Claims] (1) In a monolithic catalyst container into which a monolithic catalyst carrier is press-fitted with a wire net interposed therebetween, a tapered portion is formed on the inner circumference of the monolithic catalyst container, which is a monolithic catalyst carrier insertion portion, and is tapered in the direction of press-fitting. and a monolithic catalyst container characterized by being provided with a recess or a protrusion having a stepped portion. (2) The monolithic catalyst container according to claim 1, wherein the length of the stepped portion in the cross-sectional shape of the recess or projection is 4 or more of the outer diameter of the wire constituting the wire net. (3) The monolithic catalyst according to claim 1, wherein the recess or protrusion extends over the entire circumference of the monolithic catalyst container, and one or more recesses or protrusions are installed in each corner. container. (4) The monolithic catalyst container according to claim 1, wherein one or more recesses or protrusions are spirally provided on the inner peripheral surface of the monolithic catalyst container.