JP3190769B2 - Particulate trap device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a particulate trap device for trapping and removing fine particles contained in exhaust gas of a diesel engine.

[0002]

2. Description of the Related Art There is a particulate trap device in which a plurality of filters for collecting fine particles (particulates) in exhaust gas are installed in an exhaust passage of a diesel engine, and a backwash nozzle is provided downstream of each filter.

[0003] This device has a combustion chamber below the filter, and during regeneration of the filter, closes a valve downstream of the filter so as to prevent exhaust gas from flowing through the filter.
The high-pressure air is blown out from the backwash nozzle, and the trapped particulates are blown down from the corresponding filter into the combustion chamber, and are combusted and removed by the heater of the combustion chamber. Each filter is periodically regenerated. (Japanese
188613, 3-18609, 4-10902
No. 0).

[0004]

SUMMARY OF THE INVENTION In such a conventional apparatus,
In this case, the filter at the time of reproduction (the filter on the reproduction side)
Exhaust flow into the engine is regulated, and exhaust from the engine is
Pass through the non-regenerative filter. Play is short
The exhaust air to the filter in the meantime.
As the inflow is regulated, the engine can be
Considering that the output may decrease, giving
Can be obtained .

An object of the present invention is to solve such a problem.

[0006]

According to a first aspect of the present invention, as shown in FIG. 1, a plurality of filters 1 and 2 for collecting particulates contained in exhaust gas of an engine are provided in parallel, Valve devices 3 and 4 for restricting inflow of exhaust gas
And a backwashing device 5, 6 for blowing high-pressure air from the downstream side of the filter to blow down trapped particulates.
In the apparatus , means 10 for periodically generating a filter regeneration request, means 7 for detecting the load on the engine, and means for detecting the load on the filter when the load on the engine is 5% or less of the maximum load at the time of the request for regeneration of the filter. In addition to controlling the valve devices 3 and 4 and the backwashing devices 5 and 6 to perform regeneration, when the load on the engine is not less than 5% of the maximum load, a predetermined time elapses from the time when the filter regeneration request is issued. Means 8 for controlling the valve devices 3 and 4 and the backwash devices 5 and 6 to regenerate the filter after waiting is provided.

According to a second aspect of the present invention, as shown in FIG. 1, a plurality of filters 1 and 2 for collecting particulates contained in exhaust gas of an engine are provided in parallel, and the flow of exhaust gas to the filters during regeneration is restricted. In a particulate trap filter device including valve devices 3 and 4, and backwash devices 5 and 6 for blowing high-pressure air from the downstream side of the filter to blow down trapped particulates, a filter regeneration request is periodically sent. Means 10 for detecting the rotational speed of the engine, means 9 for detecting the rotational speed of the engine, and the valve device 3 for regenerating the filter when the rotational speed of the engine is 80% or less of the rated rotation at the time of request for regeneration of the filter. ,
4 and the backwashing devices 5 and 6, and when the rotation speed of the engine is not less than 80% of the rated rotation, the regeneration of the filter is waited until a predetermined time elapses from the generation time of the filter regeneration request. Valve device to do 3,
4 and means 8 for controlling the backwashing device 5,6, Ru and provided <br/>.

In the first aspect of the present invention, at the time of trap regeneration, the flow of exhaust gas into the filter (regeneration-side filter) is regulated, and the entire amount of exhaust gas from the engine is exhausted through the non-regeneration-side filter. . This regeneration process is performed when the load on the engine is 5% or less of the maximum load when a filter regeneration request is generated. That is, the filter
Is not limited to when the engine is idle, but also when the vehicle decelerates.
Engine output is not required
Exhaust flow to the regeneration side filter.
Due to the on-going regulation, the exhaust pressure increases (and the engine output decreases).
Even if there is (bottom), it does not give uncomfortable feeling in driving .
When the load on the engine is not less than 5% of the maximum load, the regeneration process of the filter is performed after a lapse of a predetermined time from the time of the generation of the regeneration request. ) Is not easily established, and the particulate matter collected by the filter is excessively deposited.
Uh, nothing like that. These results in excessive filter
Filter in that range while preventing clogging
Is not affected by the regular playback process of
Good driving performance without a sense of incompatibility can be secured .

In the second invention, when a request for regeneration of the filter is generated, the regeneration process of the filter is performed when the rotation speed of the engine is 80% or less of the rated rotation, that is, when the exhaust gas flow rate is relatively small. The exhaust pressure of the engine does not increase so much and has almost no effect on the engine output. In addition, the rotation speed of the engine is set to 80 of the rated rotation.
If not less than%, the filter is regenerated after a lapse of a predetermined time from the point at which the regenerating request is issued, so that excessive clogging of the filter is prevented as in the first invention.
While in that range, the filter is made regularly
Good luck without any discomfort without being affected by the playback process
Toughness can be secured .

[0010]

FIG. 2 shows an embodiment of the present invention. Reference numeral 20 denotes a trap body installed in an exhaust passage of a diesel engine.

In the trap body 20, the flow path in the main body 20 is divided into two systems, and filters 21 and 22 for trapping particulates are interposed in the respective flow paths.

The flow path 23 downstream of the filters 21 and 22
The shutter valves 24 and 24 are provided with shutter valves 25 and 26, respectively.

The shutter valves 25, 26 are
The channels 23 and 24 are closed when the air is sent from the air reservoir 29 by opening the channels 7 and 28, and the channels 23 and 24 are opened when the electromagnetic valves 27 and 28 are closed and the air is shut off. .

Filters 21 and 22 are provided in the trap body 20.
A combustion chamber 30 is formed below the heater, and a heater 31 is installed in the combustion chamber 30.

On the downstream side of the filters 21 and 22 of the trap body 20, a backwash nozzle 3 as a backwash device is provided.
2, 33 are installed.

High-pressure air from the air reservoir 29 is sent to the backwash nozzles 32 and 33 via solenoid valves 34 and 35, respectively. When the solenoid valves 34 and 35 are opened, the high-pressure air is directed to the filters 21 and 22. It is designed to blow out.

In order to detect the engine load, an engine load sensor 36 for detecting the opening of the injection lever of the fuel injection pump and the like is provided.

The controller 37 periodically issues a request for regeneration of the filters 21 and 22, and based on the regeneration request and the engine load signal of the engine load sensor 36, the solenoid valves 27, 28, 34 and 35 and the heater 31.
Is controlled. Reference numeral 38 denotes a battery.

The air reservoir 29 is connected to a compressor of the engine (not shown).
When the internal pressure drops to a reference value, air is replenished by the compressor until a predetermined high pressure is reached.

Next, the contents of control by the controller 37 will be described with reference to the flowchart of FIG.

When a filter regeneration request is generated, first, in step 1, the engine load L is compared with a specified value L ₀ (for example, 5% of the maximum load). The specified value L ₀ is a reference for detecting that the load is zero or almost zero at the time of idling, deceleration, shift change, and the like of the engine.

If the engine load L is lower than the specified value L _{0, the} filter 21 (first block) is regenerated in step 3.

If the engine load L is higher than the specified value L ₀ , the process waits at step 2 and the engine load L is reduced to the specified value L _{0.
If the value} is lower than ₀ , the process proceeds to step 3, where the filter 21 is regenerated. Incidentally, if this time the predetermined time t ₁₀ is elapsed,
Similarly, the process proceeds to step 3, where the filter 21 is regenerated.

To regenerate the filter 21, the shutter valve 25 of the flow path 23 is closed to prevent exhaust gas from flowing to the filter 21, and the electromagnetic valve 34 is opened to open the air reservoir 2.
9, high-pressure air is sent to the backwash nozzle 32,
, The trapped particulates are blown down into the combustion chamber 30. In this case, the solenoid valve 34 is driven to open for a very short time so as to blow out high-pressure air in a pulsed manner, and then driven to close. The particulates falling into the combustion chamber 30 are incinerated by the heater 31.

After the regeneration of the filter 21, the shutter valve 25 is opened.

Thereafter, when a predetermined time t ₂₀ (for example, 10 seconds) elapses, the engine load L is reduced to a specified value L in step 5.
_If the engine load L is lower than the specified value L _{0, the} filter 22 (the second block) is regenerated in step 7.

If the engine load L is higher than the specified value L ₀ , the process waits at step 6 and the engine load L is set to the specified value L 0.
_{If the value} is lower than ₀ , the process proceeds to step 7, and the filter 22 is reproduced. Incidentally, if this time the predetermined time t ₁₀ is elapsed,
Similarly, the process proceeds to step 7, where the filter 22 is reproduced.

To regenerate the filter 22, the shutter valve 26 of the flow path 24 is closed to prevent exhaust gas from flowing to the filter 22 side, and the solenoid valve 35 is opened to open the air reservoir 2.
9, high-pressure air is sent to the backwash nozzle 33,
, The trapped particulates are blown down into the combustion chamber 30. In this case, the solenoid valve 35 is driven to open for a very short time so as to blow out high-pressure air in a pulsed manner, and then driven to close. The particulates falling into the combustion chamber 30 are incinerated by the heater 31.

When the regeneration of the filter 22 is completed, the shutter valve 26 is opened and the process is completed.

Since the regeneration of the filters 11 and 12 is performed when the engine load is equal to or less than the predetermined value, the operability is not affected.

That is, when the filter is regenerated, the entire amount of exhaust gas flows to the non-regeneration side filter to close the shutter valve of the corresponding flow path. Since it is performed when there is no output request such as at the time, even if the exhaust pressure increases, it does not affect the engine output.

In this case, the discharge pressure rises (for a very short time) due to the air blown out from the backwash nozzle (the air flows into the non-regeneration side filter through the combustion chamber 30 side). However, this ensures good driving performance without a sense of incongruity.

When the engine load is not lower than the predetermined value, the regeneration is performed after the predetermined time has elapsed, so that it is possible to prevent excessive accumulation of particulates on the filter.

FIG. 4 shows another embodiment of the present invention.
When the engine speed is equal to or less than a predetermined value, the filter 21
22 is reproduced.

In this case, as shown in FIG. 2, an engine rotation speed sensor 40 for detecting the rotation speed of the engine is provided.
28, 34, 35 and the heater 31 are controlled.

When a filter regeneration request is issued, the engine speed N is compared with a specified value N ₀ (for example, 80% of the rated speed) in step 11.

If the engine rotational speed N is lower than the specified value N _{0, the} filter 21 (first block) is regenerated in step 13.

If the engine speed N is higher than the specified value N ₀ , the process waits at step 12 and the engine speed N
Is lower than the specified value N ₀ , the process proceeds to step 13 and the filter 21 is regenerated. Incidentally, if this time the predetermined time t ₁₀ is elapsed, again proceeds to step 13, the filter 21
Perform playback.

After a predetermined time t ₂₀ (for example, 10 seconds) has elapsed after the regeneration of the filter 21, the engine speed N is compared with a specified value N ₀ in step 15.
Is smaller than the specified value N _{0, the} filter 22 (second block) is reproduced in step 17.

If the engine speed N is higher than the specified value N ₀ , the process waits at step 16 and the engine speed N
Is lower than the specified value N ₀ , the process proceeds to step 17, and the filter 22 is regenerated. Incidentally, if this time the predetermined time t ₁₀ is elapsed, again proceeds to step 17, the filter 22
Perform playback.

If the regeneration of the filters 11 and 12 is performed when the engine rotation speed is equal to or lower than the predetermined value, that is, when the exhaust gas flow rate is relatively small, the exhaust pressure does not increase so much. Influence on the vehicle is avoided, and no uncomfortable feeling is given, and good driving performance is secured.

Since the rise in the exhaust pressure is suppressed, the pressure difference from the air blown from the backwash nozzle is increased, and the regeneration efficiency is improved.

[0043]

According to the first invention, a valve device is provided in parallel with a plurality of filters for collecting particulates contained in the exhaust gas of an engine, and restricts the flow of the exhaust gas into the filters during regeneration. in likewise particulate trap filter device and a backwash device lowering blow collecting particulates blows high pressure air from the downstream side to the filter, periodic regeneration requests of the filter
And a means for detecting the load of the engine,
Engine load is maximum negative when filter regeneration request occurs
When less than 5% of the load, the filter is
Control the lube and backwash units, and
Filter when gin load is not less than 5% of maximum load
Wait for a predetermined time to elapse from the time when the playback request is issued
Valve and backwash to regenerate the filter
And means for controlling the device, since the provided excessive filter
Filter in that range while preventing clogging
Good luck without discomfort despite regular regeneration
Toughness can be secured .

According to the second aspect of the present invention, a plurality of filters for collecting particulates contained in the exhaust gas of the engine are provided in parallel, and a valve device for restricting the exhaust gas from flowing into the filters during regeneration is provided. in particulate trap filter apparatus comprising a backwash device which blows high pressure air blow down the collecting particulates from the downstream filter, and periodically the reproduction request filter
Means for generating and means for detecting the rotational speed of the engine
And the engine speed at the time of the filter regeneration request
Regeneration of the filter when is less than 80% of rated rotation
While controlling the valve device and backwashing device to perform,
Similarly, if the engine speed is less than 80% of the rated speed
When the filter regeneration request is
Wait for the filter to regenerate the filter
Means for controlling the filter device and the backwashing device.
, Regardless of the regular regeneration process of the filter,
Good driving performance without a sense of harmony can be secured .

[Brief description of the drawings]

FIG. 1 is a configuration diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a flowchart showing control contents.

FIG. 4 is a flowchart showing control contents of another embodiment.

[Explanation of symbols]

 Reference Signs List 20 trap body 21, 22 filter 25, 26 shutter valve 27, 28 solenoid valve 29 air reservoir 30 combustion chamber 31 heater 32, 33 backwash nozzle 34, 35 solenoid valve 36 load sensor 37 controller 40 rotation speed sensor

Claims (2)

(57) [Claims] 1. A valve device for providing a plurality of filters for collecting particulates contained in exhaust gas of an engine in parallel, and restricting the flow of exhaust gas into the filters during regeneration,
Also Te particulate trap filter apparatus odor <br/>; and a backwash device lowering blow collecting particulates blows high pressure air from the downstream side to the filter, periodically means for generating a playback request for the filter Means for detecting the load on the engine, and controlling the valve device and the backwashing device to regenerate the filter when the load on the engine is 5% or less of the maximum load at the time of the request for regeneration of the filter. and means for controlling the valve device and a backwashing device to perform the playback of the filter waits for the predetermined time from the occurrence time of the filter regeneration request elapses when the engine load is not more than 5% of the maximum load, the A particulate trap filter device provided. 2. A valve device for providing a plurality of filters for collecting particulates contained in exhaust gas of an engine in parallel, and restricting the flow of exhaust gas to the filters during regeneration,
Also Te particulate trap filter apparatus odor <br/>; and a backwash device lowering blow collecting particulates blows high pressure air from the downstream side to the filter, periodically means for generating a playback request for the filter Means for detecting the rotation speed of the engine, and controlling the valve device and the backwashing device to regenerate the filter when the rotation speed of the engine is equal to or less than 80% of the rated rotation when a regeneration request for the filter is issued. Similarly, when the engine rotation speed is not less than 80% of the rated rotation, a means for controlling the valve device and the backwashing device so as to regenerate the filter after a predetermined time has elapsed from the time when the filter regeneration request is issued. If, particulate trap filter device, characterized in that the provided.