JPH064018Y2 - Particulate trap with electric heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a particulate trap provided in an exhaust system for collecting particulates (solid fine particles) discharged from an internal combustion engine, and particularly relates to a regeneration assist. The present invention relates to the structure of a particulate trap provided with an electric heater as a means.

[Conventional technology]

Japanese Patent Laid-Open No. 58-124013 is known as a prior art related to the present invention. In the particulate trap disclosed in this publication, the electric heater is provided with a support member having a plurality of linear bodies to prevent the electric heater from being displaced during assembly, and to prevent a short circuit between the heaters due to twisting. It has improved stickiness.

FIG. 3 shows a conventional particulate trap with an electric heater. In the figure, 1 indicates a filter for collecting solid particles contained in the exhaust gas. Filter 1
The electric heater 2 is located on the upstream side of. Filter 1
Are stored in the case 3. Case 3
Is divided into two in a direction orthogonal to the flow direction of the exhaust gas. The filter 1 is held on one case 3a via a holding member 4, and the electric heater 2 is provided between the divided flange portion 3c of the case 3a and the flange portion 3d of the other case 3b. It is installed. Then, the case 3a and the case 3b are fastened by bolts 5 inserted into the respective flange portions.

[Problems to be solved by the invention]

However, in the particulate trap with an electric heater shown in FIG. 3, since the electric heater 2 is fixed by the flange portions 3c and 3d of the case 3 extending in the circumferential direction, there is a drawback that the trap itself becomes large. there were. That is, there is a problem that the mounting space for the particulate trap becomes large and the weight increases. There is also a problem that a plurality of bolt holes have to be bored in each flange of the case, resulting in an increase in cost.

In view of the above problems, the present invention aims to provide a particulate trap with an electric heater in which fixing of the electric heater by a bolt inserted into a flange is abolished and the size and cost can be reduced.

[Means for solving problems]

A particulate trap with an electric heater according to the present invention for this purpose collects the solid particulates in the particulate trap with an electric heater that captures and regenerates the solid particulates contained in the exhaust gas discharged from the internal combustion engine. A case accommodating the filter and the electric heater as the regeneration means is divided into two in a direction parallel to the flow direction of the exhaust gas, and one of the divided cases has a flange portion where the lead wire of the electric heater is located. A lead wire take-out hole for exposing a part of the electric heater is formed, and a welding hole for exposing the flange portion of the electric heater is formed on the other case. The joint between the divided cases and the case and the electric heater exposed from the case are formed. It is composed by welding the parts of the.

[Action]

In the particulate trap with an electric heater configured as described above, the case is divided into two parts in a direction parallel to the flow direction of the exhaust gas, so that the joint portion of the case is circumferentially arranged as in the conventional case. It is not formed in the extending direction. Therefore, the outer diameter is reduced accordingly, and the particulate trap can be downsized.

Also, since the electric heater is fixed to the case by welding, it is not necessary to drill bolt holes in the flange and fixing bolts and nuts as in the past, which reduces the weight of the particulate trap and reduces the cost. It can be downed.

[Embodiment] A preferred embodiment of the particulate trap with an electric heater according to the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention. In the figure, 11 indicates a particulate trap with an electric heater. This particulate trap 11 with an electric heater is attached to the exhaust system of a diesel engine. Particulate trap with electric heater 11
Is a case 12 made of a metal plate, an electric heater 13 as an auxiliary means for regenerating particulates, a filter 14 for collecting particulates, and a holding material 15 for holding the filter 13.
It consists of The case 12 houses the electric heater 13, the filter 14, and the holding material 15, and is divided into two in a direction parallel to the flow direction of the exhaust gas. That is, the case 12 is composed of the upper case 16 and the lower case 17.

The upstream portion 12a of the case 12 is formed in a truncated cone shape whose flow passage area increases toward the downstream side. Case 12
On the contrary, the downstream portion 12b is formed in a truncated cone shape in which the flow passage area becomes smaller toward the downstream side. A cylindrical holding portion 12c in which the electric heater 13 and the filter 14 are located is formed between the upstream portion 12a and the downstream portion 12b of the case 12. The filter 14 is held on the downstream side of the holding portion 12c via a holding material 15 as a cushion material.

An electric heater 13 is arranged immediately upstream of the filter 14. The electric heater 13 is a zigzag electric heater element 13a.
And a flange portion 13b for holding the electric heater element 13a. The flange portion 13b is formed with a protrusion 13c that protrudes outward in the radial direction.
Lead wire 13d is taken out from 13. Lead wire 13d
Is connected to a power source (not shown). The holding portion 12c of the case 12 is formed with a lead wire take-out hole 16a that exposes the protruding portion 13c of the flange portion 13b where the lead wire 13d of the electric heater 13 is located. The lead wire take-out hole 16a is
It is formed only in the upper case 16, and the edge 16b of the lead wire take-out hole 16a is slightly raised outward. Further, the holding portion 12c of the case 12 has an electric heater.
A welding hole 17a is formed so that the flange portion 13b of 13 is exposed. The welding hole 17a is provided only in the lower case 17.

The electric heater 13 housed in the case 12 is joined to the case 12 by welding. That is, the protruding portion 13c of the flange portion 13b of the electric heater 13 protruding from the heater wire taking-out hole 16a is joined to the edge portion 16b of the heater wire taking-out hole 16a by the entire circumference welding 18. The flange portion 13b of the electric heater 13 is joined to the case 12 by filling the welding hole 17a of the case 12 with the weld 18.

The joints 16c and 17c between the upper case 16 and the lower case 17 are
In Fig. 2, it extends slightly in the horizontal direction.
16c and 17c are joined by welding so that there is no gas leakage.

Next, the order of assembling the above-mentioned particulate trap with an electric heater will be described.

First, in the lead wire take-out hole 16a of the upper case 16 in the case 12, the protrusion 13c of the flange 13b of the electric heater 13
Is fitted. Then, the holding material 15 is provided on the outer periphery of the filter 14.
Is attached, and the filter 14 is arranged on the downstream side of the electric heater 13. After that, the upper case 16 and the lower case 17 are overlapped with each other, and the joining portion 16c of the upper case 16 and the joining portion 17c of the lower case 17 are joined by welding.

When the upper and lower cases 16 and 17 are joined together, the upper case 1
The edge portion 16b of the lead wire take-out hole 16a of 6 and the protruding portion 13c of the flange portion 13b of the electric heater 13 are welded all around. Then, after that, the lower case 16 and the electric heater 13 are joined by filling the welding hole 17a by welding. That is, each joint is carefully welded so that there is no gas leakage.

In the particulate trap with an electric heater configured as described above, the exhaust gas flowing from the upstream side of the case 12 passes through the space between the electric heater elements 13a of the electric heater 13, passes through the filter 14, and passes through the case. It is led to the downstream side of 12. In this case, most of the solid fine particles are collected by the filter 14. Then, when the solid fine particles collected by the filter 14 reach a predetermined amount, the electric heater 13 is energized, the solid fine particles such as soot are incinerated, and the filter 14 is regenerated.

Since the electric heater 13 is fixed to the case 12 by welding, the circumferentially extending flange shown in FIG. 3 is unnecessary, and the outer diameter of the case 12 is significantly reduced as compared with the conventional case. . Therefore, the particulate trap 11 with an electric heater can be downsized, and the mounting space for the exhaust system can be reduced.

Further, since the bolt hole for fixing the electric heater 13 and the bolt and the nut are not required, the weight is reduced and the cost is reduced. In other words, the fixing structure by welding is technically easier to automate and the equipment is cheaper than the fixing structure by bolts and nuts.
As a result, the assembly cost of the particulate trap can be reduced.

[Effect of device]

As described above, in the case of the particulate trap with an electric heater according to the present invention, the case containing the electric heater and the filter is divided into two parts in a direction parallel to the exhaust gas flow direction and exposed from the case. Since the portion of the electric heater to be joined to the case is welded to the case, a flange extending in the circumferential direction for fixing the electric heater as in the conventional case is not required, and the particulate trap can be downsized.

Further, unlike the prior art, it is not necessary to form a bolt hole in the flange, and a bolt and a nut, so that the weight can be reduced and the assembling cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a particulate trap with an electric heater according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a conventional particulate trap with an electric heater. FIG. 7 is a cross-sectional view of the trap. 11 …… Particulate trap with electric heater 12 …… Case 13 …… Electric heater 13b …… Flange 13d …… Lead wire 14 …… Filter 16a …… Lead wire take-out holes 16c, 17c …… Case joint 17a… … Weld holes

Claims (1)

[Scope of utility model registration request] 1. A particulate trap with an electric heater for collecting and regenerating solid fine particles contained in exhaust gas discharged from an internal combustion engine, comprising: a filter for collecting the solid fine particles and an electric heater as a regenerating means. The case to be stored is divided into two parts in a direction parallel to the flow direction of the exhaust gas, and one of the divided cases is provided with a lead wire take-out hole for exposing a part of the flange portion where the lead wire of the electric heater is located. Forming a welding hole in which the flange portion of the electric heater is exposed in the other case, and joining the divided cases and the case and the portion of the electric heater exposed from the case by welding. A featured particulate trap with an electric heater.