JPH0415930Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a particulate filter device installed in the exhaust system of a diesel engine.

Diesel engine exhaust gas contains flammable particulates called particulate matter. This particulate is composed of soot and unburned carbonized compounds, and is not only the main cause of exhaust gas graphitization, but also has the potential to be harmful to the human body. , simply referred to as DPF), is being actively researched into technology to purify exhaust gas.

The technology of using a split casing called the Clam-Shell Canning method to incorporate a plate-shaped ceramic foam into a DPF is highly regarded as a highly productive technology. The ceramic foam is installed inside the casing via a ring-shaped support material, but in the past, when closing the split mold, accidents such as the ceramic foam being misaligned or being closed too tightly and damaging the ceramic foam have occurred. was. For this reason, it is necessary to strictly control the accuracy of positioning the ceramic foam and the compression margin for the support material, and for example, a technique described in Japanese Utility Model Application Publication No. 54-61916 has been devised.

Therefore, the object of this invention is to provide an improved DPF device that can accurately mount a ceramic foam into a clamshell type casing with an appropriate holding force.

The DPF device according to this invention is characterized by the structure of a support member interposed on both axial end faces of a ceramic foam formed, for example, in the shape of a flat elliptical column. Of both end faces of the ceramic foam, the supporting material on the exhaust gas outflow side in the axial direction consists of a ring-shaped cushion material and a rigid protector, and the supporting material on the exhaust gas inflow side in the axial direction consists of a ring-shaped compression material. It consists of a deformable supporter.

The supporter extends to cover part of the outer periphery of the ceramic foam, and deforms along the shoulder of the ceramic foam when the ceramic foam is installed in the casing. Therefore, since the ceramic foam is held between the protector made of cushion material and a rigid body on one side and the compressible supporter on the other side, the retention of the ceramic foam within the casing is ensured, and compression allowance can be controlled. It also becomes easier.

An embodiment of this invention will be described below with reference to the accompanying drawings. Figure 3 is a plan view of the DPF device excluding the clam shell upper mold, and Figure 4 is shown in Figure 3.
The front view of the DPF device, Figure 5, is shown in Figure 3.
FIG. 3 is a left side view of the DPF device. The clamshell type casing 1 consists of an upper mold 11 and a lower mold 12,
After the ceramic foam 2 is installed, the flange portions 11a and 12a are joined to each other for assembly. The ceramic foam 2 is formed in the shape of a flat elliptical cylinder with a catalyst, and in the recesses 11b and 12b formed in the upper mold 11 and the lower mold 12,
It is fitted in a V-shape vertically and concave in the exhaust gas flow direction shown by the arrow, with the radial support member 3 and the axial support member 4 interposed therebetween. The radial direction refers to the radial direction since the ceramic foam 2 is formed into a flat elliptical cylinder shape, and the axial direction refers to the axial direction. Therefore, the outer peripheral surface 2a of the ceramic foam 2 is located in the radial direction, and both end surfaces 2b and 2c of the ceramic foam 2 are located in the axial direction.

As shown in an enlarged cross-section in FIG. It is made of heat-foamable ceramic fiber called Intalum Mat. A ring-shaped cushion material 41 is provided on the outer end surface 2b of the ceramic foam 2 in the axial direction.
is arranged so that a part thereof contacts the radial support member 3 and a part thereof contacts the end surface 2b, and a protector 42 is arranged between the outside thereof and the side surfaces of the recesses 11b and 12b of the casing 1. The cushion material 41 is made of press-formed wire mesh, and the protector 42 is made of press-formed steel plate, which are welded together and integrated. The protector 42 is a reinforcing member, and as shown in FIG. Prevents interference with. This is because this shoulder R has a curved surface, which makes it difficult to achieve dimensional accuracy, and if the protector 42 is applied to this shoulder R, it becomes difficult to achieve accurate positioning of the ceramic foam 2 in the axial direction. Note that the symbol P indicates a welded portion.

A supporter 43 is disposed on the inner side 2c of the ceramic foam 2 in the axial direction, and is in contact with a portion of the outer circumferential surface 2a of the ceramic foam 2, and a portion of which is in contact with the end surface 2c. This supporter 43
is a corrugated ring-shaped wire mesh that is wound next to the radial support member 3 on the outer peripheral surface 2a of the ceramic foam 2, and is pressed against the sides of the recesses 11b and 12b of the casing 1 during mold clamping. It deforms and comes into contact with the end surface 2c.

This DPF device is assembled as follows. First, place 2 on the outer peripheral surface of ceramic foam 2.
The radial support material 3 is wound around the radial support material 3, and the supporter 43 is wound next to it, and then the integrated cushion material 41 and protector 42 are attached to the axial outer end surface 2b of the ceramic foam 2, and the lower mold of the casing 1 is attached. 12 into the recesses 12b. Next, the concave portion 11b of the upper mold 11 is placed over these members and pressed, thereby forming both the flange portions 11a and 12a.
join. At the time of this pressing, the cushion material 41 and the protector 42 are subjected to strong surface pressure, and the supporter 43 is compressively deformed along the shoulder of the ceramic foam 2, and the ceramic foam 2 is attached to the casing 1.
It is securely held in both the recesses 11b and 12b.

As mentioned above, the DPF device according to this invention is
Supporting the ceramic foam in the axial direction,
The exhaust gas outflow side end face is supported by a protector made of cushion material and a rigid body, and the exhaust gas inflow side end face is supported by a compressively deformable supporter and fitted into the recess in the casing, so that the exhaust gas can be compressively deformed. The surface pressure holding force of the support material on the exhaust gas outlet side end face is greater than that of the support material on the inflow side end face,
Therefore, the accuracy required for the casing and the ceramic foam for compression allowance management is relaxed, and the ceramic foam can be installed in the casing with an appropriate holding force and with high positional accuracy.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main part showing an embodiment of this invention, Fig. 2 is an enlarged view of part A in Fig. 1, and Fig. 3 is a plan view of an embodiment of this invention excluding the upper mold. Figure 4 is a front view of one embodiment of this invention;
The figure is a left side view of one embodiment of this invention. DESCRIPTION OF SYMBOLS 1... Casing, 11... Upper mold, 12... Lower mold, 11a, 12a... Flange part, 11b, 1
2b... recess, 2... ceramic foam, 2a
...Outer peripheral surface, 2b...Exhaust gas outflow side end surface, 2c
... Exhaust gas inflow side end face, 3 ... Radial direction support material, 4 ... Axial direction support material, 41 ... Cushion material, 42 ... Protector, 43 ... Supporter.

Claims (1)

[Claims for Utility Model Registration] A clamshell type casing installed in an engine exhaust system, a flat plate-shaped casing with a shorter axial length than the diameter of the exhaust gas inflow surface, and a ceramic foam for collecting particulate matter; a recess formed in the casing for mounting the ceramic foam in the casing and accommodating the outer periphery of the ceramic foam; The radial direction support material is composed of a radial support material interposed between the recess and an axial support material interposed between both axial end surfaces of the ceramic foam and the side surfaces of the recess. In the diesel particulate filter device in which the ceramic foam is fixed by the ceramic foam and the axial support member, the exhaust gas outflow side end face of the ceramic foam in the axial direction and the exhaust gas outflow side end face of the ceramic foam in the axial direction. The axial direction support material interposed between the side surface of the recess is an integral part of a cushion material and a protector made of a rigid body, and on the other hand, between the exhaust gas inflow side end surface on the opposite side and the side surface of the recess. A part of the axial support member interposed in the ceramic foam extends to the outer circumferential surface of the ceramic foam, and when the ceramic foam, radial support member, and axial support member are fitted into the recess, the ceramic foam is inserted into the recess. A diesel particulate filter device consisting of a sahota that compresses and deforms along the shoulder of the foam.