JP2543776Y2 - Particulate removal equipment - 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 removing device for collecting particulates contained in exhaust gas from a diesel engine or the like.

[0002]

2. Description of the Related Art Exhaust gas from a diesel engine contains a high concentration of exhaust fine particles (particulates) mainly composed of carbon produced by combustion, which causes pollution. Therefore, an exhaust system of a vehicle equipped with a diesel engine is provided with a particulate removing device that collects particulates in exhaust gas with a filter.

In recent years, in order to prevent the filter from being clogged, a technique has been proposed in which compressed air (backwashing air) acts on the filter in a direction opposite to the flow of the exhaust gas to separate and drop the particulates from the filter. It has been developed (Japanese Unexamined Patent Publication No. 2-45609 "Particulate trap device", Japanese Utility Model Application Laid-Open No. 59-68117 "Diesel engine particulate processing device", etc.).

[0004]

However, these conventional particulate removal apparatuses have a configuration in which one backwash nozzle for jetting compressed air to the filter is provided downstream of the filter. The filter near the backwash nozzle was completely cleaned and regenerated by the compressed air acting sufficiently, but the edge of the filter far from the nozzle was not sufficiently acted by the compressed air and cleaning and regeneration were incomplete. .

An object of the present invention, which has been made in view of the above circumstances, is to provide a particulate removing apparatus capable of uniformly cleaning and regenerating a filter.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a filter provided in an exhaust system for collecting particulates in exhaust gas, and the filter has a high pressure in a direction opposite to the exhaust gas flow. In a particulate removal device having a backwash nozzle for ejecting air and dropping the particulates attached to the filter, the filter is formed so as to have a thickness along the exhaust gas flow, and on each of the left and right sides of the filter, A plurality of the above-mentioned backwash nozzles are provided at intervals in the exhaust gas flow direction, and a control unit for sequentially operating these backwash nozzles from the upstream side to the downstream side is provided.

[0007]

According to the particulate removing device having the above-described structure, high-pressure air is jetted from the plurality of backwash nozzles toward both left and right sides of the filter. As a result, the high-pressure air acts almost uniformly on the entire filter, so that the entire filter is uniformly cleaned.
Will be played.

The backwash nozzle is sequentially operated from the upstream side to the downstream side by the control unit. At the time of this backwash, the particulates separated from the filter are flowed downstream of the filter along with the exhaust gas flow, so that the particulates once separated do not adhere to the upstream filter again. Therefore, the cleaning degree of the filter is increased.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic top view of a particulate removing apparatus 1 for removing particulates from exhaust gas of a diesel engine, and FIG. 2 is a schematic side view. As shown in the figure, a part of the exhaust pipe 2 extending from the engine to the muffler is expanded to form a particulate removal chamber 3. In this particulate removal chamber 3,
A rectangular parallelepiped filter 4 for adhering and collecting particulates in the exhaust gas is fitted, and the filter 4 partitions the inside of the particulate removal chamber 3 into an exhaust introduction chamber 5 and a heater chamber 6 vertically.

The filter 4 has a structure as shown in Japanese Patent Application No. 2-113087, "Particulate Removal Apparatus" previously proposed by the present applicant. That is, the filter 4 is made of a porous ceramic material having air permeability, and has a plurality of exhaust gas passages (not shown) formed vertically so as to communicate with the exhaust introduction chamber 5 and the heater chamber 6. Have. The upper surface of the filter 4 faces the exhaust introduction chamber 5, the lower surface faces the heater chamber 6, and both side surfaces communicate with the muffler-side exhaust pipe 8 via the Y-shaped pipe 7. According to this configuration, the exhaust gas from the engine is guided from the exhaust gas introduction chamber 5 into the exhaust gas passage of the filter 4, then penetrates the passage side from the inside of the passage, passes through the Y-shaped pipe 7, and passes through the muffler-side exhaust pipe. It is discharged to 8. At this time, in the exhaust gas, particulates in the exhaust gas adhere and collect on the inner peripheral surface of the exhaust gas passage of the filter 4, and are discharged as a clean gas to the muffler side exhaust pipe 8.

In order to separate and drop the particulates adhered and collected on the inner peripheral surface of the exhaust gas passage of the filter 4 from the filter 4, the left and right sides of the filter 4 are provided in the particulate removal chamber 3. , And backwash nozzles 9a, 9b, which jet high-pressure air (hereinafter referred to as backwash air) in opposite directions to the flow of exhaust gas to both sides of the filter 4.
9c, 9d, 9e, 9f are provided. As shown in FIG. 1, three backwash nozzles 9 a to 9 f are provided on each of the right and left sides of the filter 4, three each at intervals along the flow of exhaust gas. Further, the filter 4 is provided so as to correspond to the six backwash nozzles 9a to 9f.
Is provided with a partition plate 10. That is, the interior of the filter 4 is partitioned into six filter units 4a, 4b, 4c, 4d, 4e, and 4f by the partition plate 10, and each of the filter units 4a to 4f is provided with the six backwash nozzles 9a to 9f. f.

The backwash nozzles 9a to 9f are connected to an air tank 12 via solenoid valves 11a to 11f, respectively. The air tank 12 is supplied with high-pressure air pressurized by a compressor (not shown). The electromagnetic on-off valves 11a to 11f are respectively C
The control unit 13 is connected to a control unit 13 having a PU, and the control unit 13 sequentially opens the exhaust gas flow from the upstream side to the downstream side (from left to right in the figure). That is, the six backwash nozzles 9a to 9f sequentially operate from the upstream side to the downstream side.

The particulates separated and dropped from the filter 4 by the ejection of the backwash air from the backwash nozzles 9a to 9f are stored in the heater chamber 6 below the filter 4, as shown in FIG. An electric heater 14 for incinerating particulates is provided in the heater chamber 6. The electric heater 14 is made of a heating resistor such as a nichrome wire, and is connected to the control unit 13. The operation is controlled by the control unit 13.

A shut valve 15a, which opens and closes the inside of the tube 7, is provided in the Y-tube 7 downstream of the filter 4.
15b are provided. These shut valves 15
a and 15b are connected to the control unit 13 so that the inside of the pipe 7 is closed at the time of back washing. Thus, at the time of back washing, the back jets ejected from the back washing nozzles 9a to 9f. The washing air is prevented from leaking to the muffler side.

An exhaust temperature sensor 1 for detecting exhaust gas temperature is provided in an engine-side exhaust pipe 16 upstream of the filter 4.
7 are provided. The exhaust gas temperature sensor 17 is connected to the control unit 13 and transmits the exhaust gas temperature to the control unit 13 after the engine is started.

The operation of this embodiment having the above configuration will be described.

As shown in FIGS. 1 and 2, in the exhaust gas from the engine, particulates in the exhaust gas are attached to and collected by the filter 4, and flow as a clean gas to the muffler side. The particulates adhered to and collected on the filter 4 in this manner are removed from the filter 4 as follows.

When the engine is started, the subsequent engine speed and load are transmitted to the control unit 13 as shown in FIG. Then, based on these transmission data, FIG.
As shown in (2), the control unit 13 calculates the amount of soot (particulates) collected by the filter 4.
When the calculated value exceeds a preset value, the control unit 13 controls the electromagnetic switching valve 1 of each of the backwash nozzles 9a to 9f.
A valve opening command is given to 1a to 1f. As a result, backwash air is ejected from the backwash nozzles 9a to 9f, and the filter 4 is backwashed. At this time, when the exhaust gas temperature from the exhaust gas temperature sensor 17 exceeds the set value (600 ° C.), the backwash may be performed. This is performed in order to prevent the particulates attached to the filter 4 from self-igniting and burning when the exhaust gas temperature exceeds a set value (600 ° C.), thereby preventing the filter 4 from being melted. By such backwashing,
The particulates attached to the filter 4 are separated and fall, and are stored in the lower heater chamber 6. Then, the control unit 1
3 gives an operation command to the electric heater 14 in the heater chamber 6,
Thus, the particulates in the heater chamber 6 are incinerated.

The backwashing step will be described in detail with reference to FIGS. As shown, when the backwashing is started, one of the two shut-off valves 15a and 15b shown in FIG. 1 is closed (for 1.5 seconds). Then, 0.2 seconds later, the electromagnetic on-off valves 11a to 11c of the backwash nozzles 9a to 9c on the side where the valve 15a is closed are sequentially opened from the upstream side at 0.4 second intervals. As a result, the backwash nozzles 9a to 9c sequentially eject high-pressure air from the upstream side. Thereafter, the shut valve 15a is opened, and the backwashing / regeneration of the filter units 4a to 4c on one side of the filter 4 is completed. Subsequently, the same control is performed on the shut valve 15b and the electromagnetic on-off valves 11d to 11f on the opposite side, and the backwash nozzles 9d to 9f sequentially eject high-pressure air from the upstream side, and the filter unit on the opposite side of the filter 4 is removed. 4d ~
The backwashing / regeneration of f ends. During this backwashing step, the heater 14 is energized from the first opening of the solenoid on-off valve 11a,
After that, the power supply is continued for 10 minutes.

As described above, according to the particulate removing apparatus 1 having the above-described structure, the plurality of backwash nozzles 9a to 9c are provided.
Since the backwash air is jetted from f to the left and right sides of the filter 4, the backwash air acts substantially uniformly on the entire filter 4, and the entire filter 4 is uniformly washed and regenerated.
Here, in the present apparatus 1, the filter 4 is partitioned into six filter units 4a to 4f by a partition plate, and the six backwash nozzles 9a to 9f are connected to the six filter units 4a to 4f. To f, the backwash air is ejected. Therefore, each backwash nozzle 9a
As for (f), each of the filter units 4a to 4f is independently washed and regenerated, and the filter 4 is efficiently washed. Further, the filter 4 is divided into filter units 4a to 4c and filter units 4d to 4f on the left and right, and the backwash is performed in the left and right order, so that the backwash can be performed without any trouble even when the engine is operating. can do.

The backwash nozzles 9a to 9f are sequentially operated by the control unit 13 from the upstream side to the downstream side. Thus, the filter 4 is washed and regenerated in order from the upstream side for each of the filter units 4a to 4f. At the time of this back washing, the particulates separated from the filter 4 flow along the exhaust gas flow to the downstream side of the filter 4, so that the particulates once separated do not adhere to the filter 4 on the upstream side again. Therefore, the degree of cleaning of the filter 4 increases. By sequentially operating the backwash nozzles 9a to 9f from the upstream side, the particulates dropped into the heater chamber 6 are moved toward the electric heater 14 located on the downstream side in the heater chamber 6. , Will burn quickly. Therefore, the durability of the electric heater 14 is improved, and the power consumption is reduced. In addition, by activating the backwash nozzles 9a to 9f in order, the consumption of air becomes gentle, and the inside of the air tank 12 is prevented from being rapidly reduced in pressure. Therefore, the durability of the air compressor that supplies pressurized air to the tank 12 is improved. Further, a conventional particulate removal apparatus (for example,
No. 45609 "Particulate Trap Device"
-68117 "Diesel engine particulate treatment equipment"
Etc.), two backwash nozzles are provided, one each for the left and right sides, which blows backwash air, so that the pressure and amount of pressurized air required for backwash can be opened and closed. Is a large and expensive solenoid valve that opens and closes the nozzle (approx.
15000 yen) and high cost (15000 x 2 = 30
However, in the particulate removal apparatus 1 of the present embodiment, since the backwash nozzles 9a to 9f are provided in a plurality, the load on each of the nozzles 9a to 9f becomes light, and the electromagnetic on-off valves 11a to 11f are attached. A small and inexpensive product (about 2000 yen) can be used, and it can be manufactured at low cost (2000 × 6 = 12000 yen).

[0023]

[Effect of the Invention] As described above, according to the particulate removal device of the present invention, the filter is uniformly cleaned and cleaned.
An excellent effect of being able to reproduce can be exhibited.

[Brief description of the drawings]

FIG. 1 is a schematic top view of a particulate removing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic side view of the particulate removal device.

FIG. 3 is a flowchart showing an entire operation of the particulate removal device.

FIG. 4 is a flowchart showing the operation of the backwash control of the particulate removal device.

FIG. 5 is a diagram showing operating times of a shutoff valve, a backwashing solenoid valve, and an electric heater of the particulate removal device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Particulate removal apparatus 4 Filter 9a-f Backwash nozzle 13 Control part

Claims (1)

(57) [Scope of request for utility model registration] 1. A filter provided in an exhaust system for collecting particulates in exhaust gas, and a filter for ejecting high-pressure air to the filter in a direction opposite to the exhaust gas flow to drop the particulates attached to the filter. In the particulate removal device provided with a washing nozzle, the filter is formed so as to have a thickness along the exhaust gas flow, and a plurality of the backwash nozzles are provided on both left and right sides of the filter at intervals in the exhaust gas flow direction. And a controller for sequentially operating these backwash nozzles from the upstream side to the downstream side.