JPS5910339Y2 - Exhaust purification device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust purification device of a type that utilizes exhaust pulsation to introduce secondary air to a catalytic converter in an internal combustion engine.

Conventionally, the exhaust ports of an exhaust manifold of an internal combustion engine are configured to be clustered near the mounting surface to the cylinder head or in the middle of the exhaust manifold.

In the exhaust collecting section, the exhaust pulsations of each air force interfere with each other and cancel each other out, and even if an attempt is made to utilize the exhaust pulsation to introduce secondary air to the catalytic converter, the effectiveness is reduced.

Furthermore, if there is a sudden cross-sectional expansion in the exhaust passage, that portion will have the same effect as the open end of the passage, and the pulsation will disappear or be weakened.

(Refer to Utility Model Application No. 51-14301) The object of the present invention is to provide an exhaust gas purification device that can eliminate the above-mentioned conventional drawbacks.

In order to achieve the above object, the present invention is characterized in that the exhaust passage from the exhaust manifold to the catalytic converter is provided with a partition wall that separates the exhaust from the exhaust ports.

With the above-described structure, the exhaust pulsations from the exhaust ports do not interfere with each other, so the pulsations can be used to effectively introduce secondary air into the catalytic converter.

In the present invention, the catalytic converter is configured as a honeycomb-shaped catalytic converter, and the partition wall is extended to the outlet of the catalytic converter to increase the effect.

Furthermore, the effect can be further increased by extending the partition wall further downstream from the outlet of the honeycomb-shaped catalytic converter to promote exhaust pulsation.

In the present invention, it is desirable to avoid rapid cross-sectional expansion of the exhaust passage and to avoid eliminating or reducing exhaust pulsation.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, an exhaust manifold 1 for a four-cylinder, four-cycle internal combustion engine has its branch parts 1a, lb, and IC attached to a cylinder head (not shown), and exhaust from each cylinder of the internal combustion engine is connected to the branch part la, lb, and IC. Accepted from lb, IC.

In the illustrated case, for example, the branch part 1a receives the exhaust gas from the first cylinder, the branch part 1b receives the exhaust gas from the second and third cylinders, and the branch part 1C receives the exhaust gas from the fourth cylinder.

As shown in FIGS. 1 and 2, the branching parts 1a and 1C are gathered together to form a collecting part 1d, which is arranged above the branching part 1b, and a partition wall 2 is provided between the collecting part 1d and the branching part 1b. The exhaust passages are separated from each other so that the exhaust pulsations at the branch portion 1b and the gathering portion 1d do not interfere with each other.

That is, in the collecting part 1d, for example, when the first cylinder is in the exhaust stroke and the exhaust gas is flowing in the branching part 1a, the branching part 1C
The 4th cylinder is in the compression stroke and the engine rotation phase is 360.
In contrast, since the exhaust valve is closed, the exhaust pulsation of the first cylinder occurs directly at the collecting portion 1d, and if the phase advances further by 360°, the opposite occurs.

Similarly, the branching portion 1b receives exhaust pulsations from the third and second cylinders, each having a rotational phase 180° different from that of the collecting portion 1d.

The outlet of the exhaust manifold 1 is connected to a catalytic converter 4 via a high mount 3, and the outlet of the catalytic converter 4 is connected to a front tube 5.

As shown in FIG. 2, the pipe 3 is also provided with a partition wall 6 that is connected to the partition wall 2, and the catalytic converter 4 is also provided with a partition wall 7 that is connected to the partition wall 6. The exhaust gas from 1d is separated separately and introduced into the catalytic converter 4.

In the present invention, secondary air inlets 8 and 9 are provided in the branching part 1b and the collecting part 1d, respectively, and are separated from each other by partition walls 2, 6, and 7 in the branching part 1b and the collecting part 1d, respectively. The secondary air is effectively introduced into the catalytic converter 4 by the exhaust pulsation.

In the present invention, the catalytic converter 4 is configured as a honeycomb type, and the internal honeycomb-shaped partition is used to extend the partition wall that partitions the exhaust pulsation, thereby increasing the effect of the exhaust pulsation, and furthermore, the catalytic converter exit By further extending the partition wall 10, the pulsating effect can be further increased.

In the above explanation, exhaust flows directed to two cylinders were collected in the exhaust manifold 1, but each cylinder
It is also possible to separate the exhaust flow for each individual.

Figures 3 and 4 show one of the catalyzers used in this invention.
As an example, a honeycomb type catalytic converter is shown in which a pair of flanges 11 at both ends have a holding piece 11a in the diametrical direction and an annular protrusion on the circumference, and are spirally wound through a wire mesh ring 12. - 13 and the wire mesh 14 and outer cylinder 15 arranged around it are pressed by the annular protrusion 1lb of the flange 11, and the honeycomb type catalytic converter 13, the wire mesh 14 and the outer cylinder 1
The groove 16 formed in the shape of the flange 11 is held in place by a holding piece 11a in the diametrical direction of the flange 11 so as to have a good sealing effect.

A sufficient gap is provided between the holding piece 11a and the groove 16 so that the holding piece 11a is not affected by thermal expansion.

The flange 11 and the outer cylinder 15 can be formed into one piece.

5 and 6 show another method of holding the honeycomb type catalytic converter 13 by the outer cylinder 17.

That is, the connection piece 17 in the diametrical direction is provided at the opening in the end surface of the outer cylinder 17.
A is bent into a U-shaped cross section to press the grooves 16 of the honeycomb type catalytic converter 13 and the wire mesh 14.

7 and 8 show a modification of the one shown in FIG. 5, in which a diametrical connecting piece 18 formed at the opening in the end face of the outer cylinder 17 has a ■-shaped slot 19, as shown in FIG. Both edges of the slot 19 in the longitudinal direction are bent inward to press the grooves 16 of the honeycomb type catalytic converter 13 and the wire mesh 14.

FIG. 9 shows a Perez I type catalyzer used in the present invention.

A pair of flanges 11 at both ends press and hold the outer cylinder 20 and the longitudinal partition wall 21 in the center, and a partition plate 22 with a number of holes provided in each space of the outer cylinder 20 divided by the partition walls 21 is used. It supports the pellets 23 of the catalytic converter.

As described above, according to the present invention, the exhaust pulsation effect can be maintained up to the catalytic converter or downstream of the catalytic converter, which provides the advantage that the required secondary air can be easily taken in due to the pulsation.

[Brief explanation of the drawing]

FIG. 1 is an external view of an embodiment of the exhaust purification device according to the present invention. FIG. 2 is a sectional view taken along arrow A-A in FIG. 1, and FIG. 3 is an end view of an example of a honeycomb type catalytic converter used in the present invention. 4 is a longitudinal sectional view of FIG. 3, and FIG. 5 is a partial longitudinal sectional view of a modification of FIG. 3. FIG. 6 is an end view of FIG. 5. FIG. 7 is an end view of a modification of FIG. 6. FIG. 8 is a partial sectional view of FIG. 7. FIG. 9 is a longitudinal sectional view of an example of a pellet type catalytic converter used in the present invention.

Claims (2)

[Scope of utility model registration request] (1) In an exhaust purification device that uses the pulsation of the exhaust from an internal combustion engine to introduce secondary air to the exhaust purification catalytic converter, a partition wall that separates the exhaust from the exhaust port runs from the exhaust manifold to the catalytic converter. An exhaust purification device characterized in that an exhaust passage is provided and a secondary air inlet is provided in each exhaust passage. (2) The exhaust gas purification device according to claim 1, wherein the partition wall is configured to separate the exhaust gas of a selected combination of exhaust ports from the exhaust gas of other combinations.