JPH0441214Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an exhaust gas purification device for internal combustion engines of vehicles, etc., and in particular improves the cylindrical part of the burner to uniformize the temperature in front of the particulate trap filter. The present invention relates to an exhaust gas purification device that converts

[Prior art]

An exhaust gas purification device for an internal combustion engine is generally installed in a part of the exhaust pipe, and is an attached device to the engine that removes substances such as carbon and hydrocarbons from the exhaust gas produced by incomplete combustion of fuel. It is.

FIG. 2 is a partially cutaway side view of such a conventional exhaust gas purification device 1. As shown in the figure, the exhaust gas purification device 1 includes a stainless steel cylinder 2a having a number of holes 2b on the outer periphery of the tip end. A burner 2 consisting of a fuel injector 3 disposed at one end of a cylinder 2a.
It also consists of a stainless steel housing 8 that houses one end of the burner 2 and a particulate trap filter 7 therein. Furthermore, inside the burner 2, a reinforcing member 2c of a cylinder 2a having a hole 2b in the center,
A glow plug 4, a secondary air inlet 5, etc. are provided. 2e is the tip of the burner 2, 6 is an exhaust pipe, and 7a is a plugging member of the particulate trap filter 7. Now, the exhaust gas that has finished being fueled in the engine (not shown) passes through the exhaust pipe 6 to the casing 8 of the exhaust gas purification device 1 as shown by arrow A.
and passes through a particulate trap filter 7. At this time, substances such as carbon and hydrocarbons contained in the exhaust gas are removed from the exhaust gas adhering to the particulate trap filter 7. After the removed substances are collected, they are re-burned to activate the particulate trap filter 7. that time,
The exhaust gas mixes with the flame emitted by burner 2 in the direction of arrow B, achieving a temperature of 600°C or higher, which is necessary for reburning. In addition, conventional exhaust gas purification devices are disclosed in Japanese Utility Model Application No. 171617/1983 or Japanese Utility Model Application No. 171617/1983.
Some are described in the 90535 specification and drawings.

[Problem that the invention attempts to solve]

In the above conventional example, the flame of the burner is strongly radiated to the central part of the front surface of the particulate trap filter, so the temperature in the central part is high, while the other parts are low (uneven temperature distribution). This causes a phenomenon in which the particulate trap filter other than the central portion is not regenerated.
The drawback was that the regeneration efficiency decreased.

The present invention has been made in view of the above points, and an object of the present invention is to provide an exhaust gas purification device for an internal combustion engine that improves regeneration efficiency so that the temperature distribution in front of a particulate trap filter is non-uniform. It is in.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention bends the vicinity of the tip of the burner cylinder inward, thereby narrowing the opening at the tip to form a constricted part.
The ratio of the opening area at the tip of the diaphragm to the cross-sectional area of the cylinder is approximately 0.05 or more.

[Effect]

By configuring as described above, a part of the flame of the burner is obstructed from advancing by the throttle part of the inner cylinder.
Since the flame is emitted to the outside of the cylinder through the large number of holes, the flame is emitted to the entire front surface of the particulate trap filter, and the temperature distribution on the front surface of the particulate trap filter can be made uniform. This improves the regeneration efficiency of the particulate trap filter.
Furthermore, since the temperature difference between the front center of the particulate trap filter and other parts is minimized, not only can the heat load on the particulate trap filter be reduced, but it also increases the temperature of the other parts. This eliminates the need to supply additional fuel, resulting in fuel savings.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the exhaust gas purification device for an internal combustion engine according to the present invention will be explained in detail based on the drawings.

FIG. 1 is a partially cutaway side view showing an exhaust gas purification device 1 for an internal combustion engine according to the present invention. Note that the same parts as in FIG. 2 are designated by the same reference numerals, and the explanation thereof will be omitted. In the figure, 2f is a constricted portion formed by bending the vicinity of the tip 2e of the cylinder 2a of the burner 2 inward.

Exhaust gas from the engine is sent into a housing 8 through an exhaust pipe 6 and proceeds to a particulate trap filter 7. Further, the fuel injected by the fuel injector 3 is ignited by the glow plug 4 to form a flame. The flame passes through the inside of the cylinder 2a and advances to the particulate trap filter 7, but a constriction part 2f is provided by bending the vicinity of the tip 2e of the cylinder 2a to narrow the opening at the tip. Therefore, the flow of the flame is obstructed by the constriction part 2f, and a part of the flame passes through the hole 2b and enters the cylinder 2a.
released to the outside. The flame emitted through the hole 2b and the flame emitted from the constricted portion 2f of the cylinder 2a merge in the housing 8, and as shown by arrow B, the flame emitted from the center of the front surface of the particulate trap filter 7 is The radiation is evenly radiated not only to the particulate trap filter 7 but also to other parts, so that the temperature of the front surface of the particulate trap filter 7 can be uniformized as a whole.

FIG. 3 is a partially cutaway side view showing another embodiment of the exhaust gas purification device according to the present invention. As shown in the figure, the closer to the opening of the tip 2e of the cylinder 2a, the more
The constricted portion 2f is configured so that the inner diameter of the cylinder 2a is gradually reduced. With this configuration, the resistance of the constricted portion 2f to the flame increases as it goes toward the tip 2e of the cylinder 2a.
As a result, the flame emitted through the hole 2b becomes uniform, and the particulate trap filter 7
The temperature distribution at the front becomes more uneven.

Note that the exhaust gas purification device for an internal combustion engine according to the present invention is not limited to the above-mentioned embodiments, and various modifications are possible, and these are not excluded within the scope of the gist of the present invention.

[Effect of idea]

As explained above in detail, according to the exhaust gas purification device for an internal combustion engine according to the present invention, the flame of the burner can be emitted to the entire front surface of the particulate trap filter. This makes it possible to improve the regeneration efficiency of the particulate trap filter, reduce the heat load on the particulate trap filter, and reduce the temperature of other parts. Since the fuel is raised, there is no need to supply a large amount of fuel, which has excellent effects such as reducing fuel costs.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing an exhaust gas purifying device for an internal combustion engine according to the present invention, Fig. 2 is a partially cutaway side view showing a conventional exhaust gas purifying device, and Fig. 3 is a partially cutaway side view showing the exhaust gas purifying device for an internal combustion engine according to the present invention. FIG. 3 is a partially cutaway side view showing another embodiment of the exhaust gas purification device for an internal combustion engine. In the figure, 1... exhaust gas purification device, 2... burner, 2a... cylinder, 2e... tip, 2f... throttle, 3... fuel injector, 4... glow plug, 7... particulate Late trap filter.

Claims (1)

[Claims for Utility Model Registration] A burner comprising a cylinder with a large number of holes formed on its outer peripheral surface near its tip, and a fuel injector disposed at the end of the cylinder on the side where the large number of holes are not formed. and a particulate trap filter disposed in front of the distal end side of the cylinder, the internal combustion engine being configured to guide exhaust gas from the internal combustion engine to the outer periphery of a portion of the cylinder in which a large number of holes are formed. In the exhaust gas purification device for an engine, the vicinity of the tip of the cylinder is bent inward to narrow the opening at the tip to form a constriction, and the opening area at the tip of the constriction is made equal to the cross section of the cylinder. An exhaust gas purification device for an internal combustion engine, characterized in that the device is smaller than its area.