JPH074820U - Particulate trap device - Google Patents

Abstract

(57) [Abstract] [Purpose] High regeneration performance is always obtained regardless of the pressure condition of the air reservoir. A plurality of filters 1 and 2 for collecting particulates in engine exhaust are provided, and high-pressure air from an air reservoir 3 is blown from the downstream side of each filter 1 and 2 at a predetermined time to collect the particulates. In a particulate trap device that blows curate down into the combustion chamber to regenerate the filters 1 and 2, depending on the means 4 for detecting the pressure in the air reservoir 3 and the pressure in the air reservoir 3 when regenerating the filters 1 and 2. The control means 5 which controls the blowing time of high pressure air is provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a particulate trap device that traps and removes fine particles contained in the exhaust gas of a diesel engine.

[0002]

[Prior art]

 In a diesel engine exhaust passage, there is a particulate trap device that has multiple filters that collect particulates (particulates) in the exhaust and a backwash nozzle downstream of each filter.

This one has a combustion chamber below the filter, and when the filter is regenerated, the valve downstream of the filter is closed so that exhaust gas does not flow to the filter, and high pressure air is blown out from the backwash nozzle. The trapped particulates are blown down from the filter into the combustion chamber, and are burned and removed by the heater of the combustion chamber, so that each filter is regenerated periodically at a predetermined time (Japanese Patent Laid-Open No. HEI-2). -188 613, 3-18609, 4-10902, etc.).

[0004]

[Problems to be solved by the device]

 In such a conventional device, the air from the air reservoir installed in the vehicle is used as the high-pressure air for backwashing. In this case, the air pressure blown out from the backwash nozzle differs depending on the pressure state in the air reservoir. Come on.

Therefore, there is a problem that the regeneration condition of the filter is affected by the pressure state in the air reservoir, and the regeneration performance is changed.

The present invention aims to solve such a problem.

[0007]

Means for Solving the Problems This invention is provided with a plurality of filters 1 and 2 for collecting particulates in engine exhaust gas as shown in FIG. At the time of, by blowing out high-pressure air from the air reservoir 3, the trapped particulates are blown down into the combustion chamber, and the particulate trap device that regenerates the filters 1 and 2 detects the pressure inside the air reservoir 3. 4 and a control means 5 for controlling the blowing time of high-pressure air according to the pressure in the air reservoir 3 when the filters 1, 2 are regenerated.

[0008]

[Action]

 Therefore, depending on the pressure in the air reservoir, the blowing time of the high-pressure air is made longer as the pressure is lower, so that the filter can always be reliably regenerated and stable regeneration performance can be maintained.

[0009]

【Example】

 FIG. 2 shows an embodiment of the present invention, and 10 is a trap body installed in an exhaust passage of a diesel engine.

In the trap body 10, the flow passage in the main body 10 is divided into two systems, and filters 11 and 12 for collecting particulates are interposed in the respective passages.

Shutter valves 15 and 16 are provided in the flow paths 13 and 14 on the downstream side of the filters 11 and 12, respectively.

When the solenoid valves 17 and 18 are opened and air is sent from the air reservoir 19, the shutter valves 15 and 16 close the flow paths 13 and 14, and when the solenoid valves 17 and 18 are closed and the air is shut off. The flow paths 13 and 14 are opened.

A combustion chamber 20 is formed below the filters 11 and 12 in the trap body 10, and a heater 21 is installed in the combustion chamber 20.

Backwash nozzles 22 and 23 are installed on the trap body 10 downstream of the filters 11 and 12, respectively.

High-pressure air from the air reservoir 19 is sent to the backwash nozzles 22 and 23 via electromagnetic valves 24 and 25, respectively, and when the electromagnetic valves 24 and 25 are opened, the high-pressure air is directed to the filters 11 and 12. It is designed to blow out.

The air reservoir 19 is provided with a pressure sensor 26 that detects the pressure inside the air reservoir 19, and the detection signal is input to the controller 27.

The controller 27 issues a regeneration request for the filters 11, 12 at a predetermined time based on engine operating conditions and the like, and based on this request and the detection signal of the pressure sensor 26, the solenoid valves 17, 18, 24 are generated. , 25 and the heater 21 are controlled. 28 indicates a battery.

When the pressure drops to a standard value, the air reservoir 19 is replenished with air by a compressor (not shown) until it reaches a predetermined high pressure.

Next, the control content of the controller 27 will be described based on the flowchart of FIG.

When a filter regeneration request is issued, the air pressure in the air reservoir 19 is read from the pressure sensor 26, and based on the air pressure, the air supply time (blowing time) to is set from the table data set as shown in FIG. Read (steps 1 and 2).

Then, the filter 11 is regenerated. In this regeneration, after closing the shutter valve 15 of the flow path 13, the electromagnetic valve 24 is opened for the to time to send the high pressure air from the air reservoir 19 to the backwash nozzle 22 and blow it out toward the filter 11 (steps 3, 4). ). As a result, the trapped particulates are blown down into the combustion chamber 20.

The solenoid valve 24 is driven to open and close so as to blow out high-pressure air in a pulsed manner, and the particulates that have fallen into the combustion chamber 20 are incinerated by the heater 21.

When the regeneration of the filter 11 is completed, the shutter valve 15 is opened (step 5).

After that, when a fixed time (for example, 10 seconds) elapses, the air pressure in the air reservoir 19 is read again from the pressure sensor 26, and the air pressure is read from the table data set as shown in FIG. 4 based on the air pressure. The supply time (blowing time) to is read (steps 6 → 7, 8).

Then, the filter 12 is regenerated. Similarly to the filter 11, this regeneration is performed by closing the shutter valve 16 of the flow path 14, then opening the to-time electromagnetic valve 25 to send high-pressure air from the air reservoir 19 to the backwash nozzle 23, and blowing it toward the filter 12. Take out (steps 9 and 10). As a result, the trapped particulates are blown down into the combustion chamber 20.

The electromagnetic valve 25 is driven to open and close so as to blow out high-pressure air in a pulsed manner, and the particulates that have fallen into the combustion chamber 20 are incinerated by the heater 21.

When the regeneration of the filter 12 is completed, the shutter valve 16 is opened and completed (step 11).

As described above, when the filters 11 and 12 are regenerated, the blowing time of the high-pressure air is controlled according to the pressure in the air reservoir 19, so that the regeneration can be accurately performed.

That is, when the pressure in the air reservoir 19 is high, the filters 11 and 12 can be sufficiently regenerated in a short blowing time of air.

When the pressure in the air reservoir 19 is low, the air is blown out for a longer time when the pressure is lower, so that the regeneration time is extended and the filters 11 and 12 can be reliably regenerated in the same manner as when the pressure is high.

Therefore, regardless of the state of the pressure in the air reservoir 19, optimum regeneration can always be performed, stable and high regeneration performance can be obtained, and waste of air is not consumed.

In particular, when the filters 11 and 12 are continuously regenerated as in the embodiment, the air pressure becomes low during the subsequent regeneration of the filter 12, but the air is blown according to the air pressure. By lengthening the time, it is possible to perform reproduction in the same manner as the filter 11 described above.

[0033]

[Effect of device]

 As described above, the present invention provides a plurality of filters for collecting particulates in the exhaust gas of the engine, and blows high pressure air from the air reservoir at a predetermined time from the downstream side of each filter to collect the particulates. In a particulate trap device that blows air into the combustion chamber to regenerate each filter, a means to detect the pressure in the air reservoir and a control means to control the blowing time of high-pressure air according to the pressure in the air reservoir when regenerating each filter. Since the and are provided, each filter can always be optimally played back, and high playback performance can be secured.

[Brief description of drawings]

FIG. 1 is a block diagram of a device.

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a flowchart showing control contents.

FIG. 4 is a characteristic diagram showing an example of setting air blowing time with respect to air pressure.

[Explanation of symbols]

 10 Trap Main Body 11, 12 Filter 15, 16 Shutter Valve 17, 18 Electromagnetic Valve 19 Air Reservoir 20 Combustion Chamber 21 Heater 22, 23 Backwash Nozzle 24, 25 Electromagnetic Valve 26 Pressure Sensor 27 Controller

Claims (1)

[Scope of utility model registration request] 1. A plurality of filters for collecting particulates in the exhaust gas of an engine are provided, and high pressure air from an air reservoir is blown from a downstream side of each filter at a predetermined time, thereby collecting the particulates in a combustion chamber. In a particulate trap device that blows down and regenerates each filter, a means for detecting the pressure in the air reservoir and a control means for controlling the blowing time of high-pressure air according to the pressure in the air reservoir during regeneration of each filter are provided. A particulate trap device characterized in that