JP2594082Y2 - Diesel engine exhaust purification system - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for purifying exhaust gas of a diesel engine, and more particularly to a device for purifying exhaust gas of a diesel engine for removing particulates contained in exhaust gas of a diesel engine.

[0002]

2. Description of the Related Art Conventionally, an exhaust gas purifying apparatus of a diesel engine has been used for purifying exhaust gas by removing particulates contained in the exhaust gas. This exhaust purification device for a diesel engine has a particulate trap filter interposed in the middle of an exhaust passage, a heating means disposed upstream of the particulate trap filter, and a particulate trap formed by combustion gas from the heating means. The particulate matter trapped in the filter is burned to regenerate the particulate trap filter.

According to such an exhaust gas purifying apparatus for a diesel engine, generally, in a particulate trap filter, the combustion gas from the heating means is guided to the vicinity of the center axis of the filter, and the particulate is burned. On the other hand, the temperature rises and combustion is sufficiently performed.
There is a problem that the combustion near the edge of the particulate trap filter is insufficient, the temperature distribution becomes uneven as a whole, and the regeneration near the edge of the particulate trap filter is insufficient.

Therefore, for example, as shown in an exhaust gas purifying apparatus for an internal combustion engine (shown in FIG. 4) disclosed in Japanese Utility Model Application No. 4-70605, an exhaust passage 101 is provided upstream from a front end face 102A of a particulate trap filter 102. A diffusion plate 103 is arranged at a predetermined distance on the side, and the combustion gas from the heating means 104 is diffused by the diffusion plate 103 to the vicinity of the edge of the front end face 102 of the particulate trap filter 102 so that the particulate trap The combustion gas is led uniformly to the filter 102 to make the combustion temperature of the particulates in the particulate trap filter 102 uniform.

[0005]

However, while the above-mentioned diffusion plate 103 is effective at the time of reproduction, there is a problem that the pressure loss of the particulate trap filter 102 is increased at the time of collection. That is, since the exhaust gas receives the back pressure from the diffusion plate 103 at all times, the pressure loss due to the exhaust gas becomes remarkable. Accordingly, there is a problem that the fuel efficiency of the engine increases, and the exhaust system components of the engine become hot, and the durability is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to uniformly introduce combustion gas to a particulate trap filter and reduce the pressure loss of exhaust gas to reduce fuel consumption of an engine. It is an object of the present invention to provide a diesel engine exhaust purification device capable of reducing exhaust gas and improving durability.

[0007]

According to the present invention, a particulate trap filter is interposed in the exhaust passage, and the particulate matter trapped by the particulate trap filter is provided upstream of the particulate trap filter. In a diesel engine exhaust purifying apparatus having a heating means for burning a late, an exhaust passage
Continued on the front end face of the Ticulate Trap filter
The cross-sectional area of the flow section decreases from upstream to downstream.
It is composed of a trumpet-shaped passage that becomes larger and larger.
The middle, at a predetermined distance from the front end surface of the particulate late trap filter upstream, of the trumpet-shaped passage
The diffusion plate is arranged so that an annular gap is formed between the diffusion plate and the wall, and the diffusion plate is in a state parallel to the flow of the exhaust gas corresponding to the collection of the particulates, or the It is characterized by being rotatable so as to select one of the right-angled states in response to reproduction.

[0008]

In the present invention, when collecting particulates, the diffusion plate is in a parallel state with respect to the flow of the exhaust gas. And pressure loss due to exhaust gas is reduced.

On the other hand, at the time of reproduction of the particulate,
Diffusion plate, it becomes a right angle state to the flow of exhaust gas
Ri, combustion gases from the heating means is uniformly guided to the particulate late trap filter through the outer diffuser, the temperature of the particulate late trap filter radius direction
Orientation .

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to 3 show a diesel engine exhaust gas purification apparatus according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an exhaust passage, and a particulate trap filter 2 is interposed in the exhaust passage 1. A bypass passage 3 is connected to the exhaust passage 1 in parallel with the particulate 2.

A branch point 4 between the exhaust passage 1 and the bypass passage 3
A first opening / closing valve 5 is interposed between the branch point 4 and the particulate trap filter 2 at a downstream side of the bypass passage 3. An on-off valve 6 is interposed.

A heating means 7 is arranged on the upstream side of the particulate trap filter 2. The heating means 7 burns the particulates collected by the particulate trap filter 2, and is attached to the heating pipe 1 </ b> A branched from the exhaust passage 1 and disposed on the axis of the particulate trap filter 2. Combustion chamber 8 and a fuel pump 9 provided on a wall of the combustion chamber 8.
A burner 10 to which fuel is supplied, a spark plug 11 disposed near a tip of the burner 10 in the combustion chamber 8, and an air blowing means 12 for sending air into the combustion chamber 8. Comprises a motor 12A and a fan 12B rotated by the motor 12A.

A particulate trap in the exhaust passage 1
The upstream portion continuing to the front end face 2A of the filter 2 is located on the upstream side
The cross-sectional area gradually increases from
It is composed of a flared passage 1A. Of the trumpet-shaped passage 1A
On the way, the front end of particulate trap filter 2
With a predetermined distance from the surface 2A to the upstream side,
So that an annular gap 1B is formed between the inner wall of the road 1A and the inner wall of the road 1A.
A diffusion plate 13 is provided, and the diffusion plate 13 is rotatably supported by a vertical rotation shaft 13A .

Reference numeral 14 denotes a control device. An actuator 15 composed of a motor is connected to the output side of the control device 14. The diffusion plate 13 is fixedly attached to a rotating shaft 13A provided on the actuator 15. I have. The output side of the control device 14 is connected to the ignition plug 11 via the fuel pump 9 and the high-pressure coil 16. The control device 14 is supplied with power from a battery 17. Further, the control device 14 controls the diffusion plate 13 to:
The actuator 15, the fuel pump 9, and the high-pressure pump are so selected as to select either a state parallel to the flow of the exhaust gas in response to the collection of the particulates or a state perpendicular to the flow in the regeneration of the particulates. A command to stop or drive the coil 16 and the motor 12A is given.

A fuel tank 18 is connected to the fuel pump 9. Next, the operation of the present embodiment will be described. As shown in FIG. 2, when collecting particulates, the first on-off valve 5 is opened, and the second on-off valve 6 in the bypass passage 3 is closed.

The exhaust gas flows through the particulate trap filter 2, and the particulates in the exhaust gas are collected by the particulate trap filter 2.
At this time, since the diffusion plate 13 is in a state parallel to the flow of the exhaust gas, during collection, the exhaust gas receives less resistance from the diffusion plate 13 and the pressure loss due to the exhaust gas is reduced. .

On the other hand, as shown in FIG. 3, the driver decides when to regenerate the particulate trap filter 2, and when regenerating the particulate, manually operates the first on-off valve 5, the second on-off valve 5, and the second. The on-off valve 6 is switched, the first on-off valve 5 is closed, and the second on-off valve 6 in the bypass passage 3 is opened. Then, the switch is manually turned on and the control device 14 is started. The heating device 7 is operated by a command from the control device 14, and the combustion gas is blown from the heating device 7 to the particulate trap filter 2. The collected particulates in the particulate trap filter 2 are burned by the combustion gas, and the particulate trap filter 2 is regenerated.

[0019] At this time, the diffusion plate 13 is a right angle state to the flow of exhaust gases, combustion gases from the heating means 7 passes through the outer diffuser 13 in particulate late trap filter in 2 The temperature is uniformly guided in the particulate trap filter 2 in the radial direction.

According to the above configuration, the rotational position of the diffusion plate 13 can be arbitrarily selected at the time of reproducing and collecting the particulates. Under the condition that the time for regeneration of the particulate trap filter 2 is short, but the time for collection is long, the influence of the collection is great. Since the state can be parallel to the flow of the exhaust gas, the pressure loss due to the exhaust gas can be reduced during collection. As a result, the fuel consumption of the engine can be reduced, and the temperature of the exhaust system components of the engine can be prevented from becoming high.
Their durability can be improved.

Of course, when the particulate trap filter 2 is reproduced, the diffusion plate 13 is used, and the temperature can be made uniform in the radial direction . As a result, the melting temperature near the axis of the particulate trap filter 2 can be improved. Loss can be prevented and the combustion of the particulates can be made uniform.

In this embodiment, the rotating shaft 13 is vertical, but it can be horizontal.

[0023]

As described above, according to the present invention, the rotating state of the diffusion plate can be arbitrarily selected at the time of reproducing and collecting the particulates. Then, when collecting the particulates in which the diffusion plate is in a state parallel to the flow of the exhaust gas, the pressure loss due to the exhaust gas can be reduced. As a result, the fuel efficiency of the engine can be reduced,
It is possible to avoid raising the temperature of the exhaust system components of the engine and improve their durability.

Of course, when the particulate trap filter is regenerated, a diffusion plate is used, and the combustion gas is led uniformly to the particulate trap filter, and its temperature is made uniform in the radial direction. Melting near the axis of the filter can be prevented, and the combustion of particulates can be made uniform.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a diesel engine exhaust purification apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of an operation state at the time of collecting particulates in the exhaust purification device for the diesel engine.

FIG. 3 is an explanatory diagram showing an operation state of the exhaust purification device for a diesel engine during regeneration of particulates.

FIG. 4 is a configuration diagram of a conventional exhaust purification device for a diesel engine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Exhaust passage 1A Trump-like passage 2 Particulate trap filter 2A Front end face 7 Heating means 13 Diffusion plate

Claims (1)

(57) [Scope of request for utility model registration] 1. A heating means for disposing a particulate trap filter in the middle of an exhaust passage, and for heating the particulate matter trapped by the particulate trap filter on the upstream side of the particulate trap filter. In a diesel engine exhaust purification device that is arranged, the front end of the particulate trap filter in the exhaust passage
As the upstream part continues from the upstream to the downstream,
The trapezoidal passage has a gradually increasing cross-sectional area, and is provided at a predetermined distance upstream from the front end surface of the particulate trap filter in the middle of the trumpet-like passage.
The diffusion plate is arranged so that an annular gap is formed between the diffusion plate and the inner wall of the passage, and the diffusion plate is moved with respect to the flow of exhaust gas in response to the collection of particulates. An exhaust gas purifying apparatus for a diesel engine, which is configured to be rotatable so as to select either a parallel state or a right angle state in response to reproduction of a particulate.