JP2002242660A - Diesel particulate filter device and its refreshing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly determine a refreshing start timing while considering an accumulation and deposition of ash generated from an lubricating oil to a filter, and efficiently removing PM while preventing a clogging in the filter. SOLUTION: This diesel particulate filter device 1 has the filter 4 for catching a particulate matter in an exhaust gas G of an engine E, and comprises a refreshing control means 50 for determining a start of a refreshing operation of the filter 4 by comparing a value measured by exhaust pressure sensors 51 and 52 with a predetermined exhaust pressure determination value ΔPes. This diesel particulate filter device 1 is constituted such that the refreshing control means 50 estimates a cumulative value of the ash which is leaked in the exhaust gas 4 and accumulated in the filter 4, and corrects the exhaust pressure determination value ΔPes for determination of the refreshing operation start based on the estimated value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diesel particulate filter device (DPF device) for collecting particulate matter of a diesel engine and purifying exhaust gas, and a method for controlling regeneration of the same.

[0002]

2. Description of the Related Art The emission level of particulate matter (PM), which is emitted from a diesel engine, has been strengthened year by year together with NOx, CO, HC, etc. Techniques have been developed to reduce the amount of PM that is collected by a filter called a particulate filter (DPF: Diesel Particulate Filter: DPF) and discharged to the outside.

[0003] DPFs for trapping PM include a monolith honeycomb type wall flow type filter made of ceramics and a fiber type filter type made of ceramic or metal in a fibrous form.
The PF device, like other exhaust gas purification devices, is installed in the middle of the exhaust pipe of the engine, and purifies and exhausts PM of exhaust gas generated by the engine.

However, the filter of the DPF device for trapping PM is clogged with the trapping of PM, and the exhaust pressure (discharge pressure) increases substantially in proportion to the amount of trapped PM. Therefore, it is necessary to remove PM from this filter, and mainly three methods and devices have been developed.

One is to use two filters to alternately switch, while one filter collects PM in exhaust gas, and the other filter collects the PM by heating the filter with an electric heater or the like. A method and apparatus for burning and regenerating PM.

The other is to use a solid filter as a filter, dispose an oxidation catalyst upstream of the solid filter, and remove PM trapped in the solid filter by a chemical reaction based on the oxidation catalyst. Processing method and apparatus.

The other is a method and an apparatus using a solid filter with a catalyst and a catalyst additive for promoting PM combustion.

[0008]

However, the cause of clogging of the filters of these DPF devices is not only soot, which is unburned fuel, but also ash remaining as unburned lubricating oil. is there.

The lubricating oil is supplied from the lubricating oil tank to various parts of the engine and around the piston ring and circulates inside the engine. However, the lubricating oil leaks into the cylinder of the engine from around the piston ring and valves.

[0010] Even if this lubricating oil is exposed to a high temperature in an engine cylinder, components such as calcium and zinc contained in the lubricating oil do not burn and remain as ash (ash). D contained in gas
It will be collected by the filter of the PF device.

[0011] The ash collected by the filter is not burned and removed even by a regeneration operation of the filter or the like, and is gradually accumulated in the filter. This leaked lubricating oil is a very small amount of about 10 liters when traveling 10,000 km, but as the traveling distance increases,
The total amount cannot be ignored, and when the traveling distance is about tens of thousands km to about 100,000 km, clogging of the filter due to accumulation and accumulation of the ash progresses, and the exhaust pressure (exhaust pressure) before and after the filter is affected. become.

On the other hand, in the conventional DPF device,
Clogging of the filter due to PM is determined by comparing the exhaust pressure measured before and after the filter with a predetermined exhaust pressure determination value, and an exhaust pressure value, a differential pressure, a pressure ratio, and the like calculated from the measured exhaust pressure are determined. Control is performed so that a filter regeneration operation is started when a predetermined determination value is exceeded.

However, in the prior art DPF apparatus, since clogging of the filter by ash generated from lubricating oil is not taken into consideration, the exhaust pressure gradually increases as the traveling distance increases. There is a problem that the determination of the start of the operation gradually becomes inappropriate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a diesel particulate filter device that estimates the state of accumulation of ash generated from lubricating oil in a filter while estimating the state of the ash. Based on the accumulated estimated value, the exhaust pressure determination value relating to the exhaust pressure used for determining the start of regeneration can be corrected or corrected, so that the start timing of the regeneration operation can be properly determined, and the PM can be efficiently removed while preventing clogging of the filter. It is to provide a diesel particulate filter device that can be used.

[0015]

A particulate filter device (DPF device) for achieving the above object is configured as follows.

1) A filter for trapping particulate matter in exhaust gas of a diesel engine, an exhaust pressure sensor provided in an exhaust passage, and an exhaust pressure measured by the exhaust pressure sensor and a predetermined exhaust pressure determination value. According to the result of the comparison, the regeneration operation of the filter is started, and the particulate matter collected by the filter is removed by combustion or a chemical reaction using a catalyst to regenerate the filter. In the filter device, the regeneration control unit estimates an ash accumulation amount in which ash leaked into the exhaust gas is accumulated in the filter, and the exhaust pressure determination for determining the start of the regeneration operation based on the ash accumulated estimation value. It is configured to modify the value.

The DPF device and its regeneration operation include:
There are the following regeneration operations corresponding to each type of DPF device, but other DPF devices and regeneration operations may be used.

DPF for alternately switching a plurality of filters
As a regeneration operation often used in the apparatus, there is an operation of energizing a heater provided in the filter, heating the filter to a temperature equal to or higher than the combustion temperature of the particulate matter, and burning the particulate matter,
As a regeneration operation for a DPF device in which a catalyst is supported on a filter, there is an operation of increasing the temperature of exhaust gas and removing particulate matter by a chemical reaction using the catalyst.

The determination by comparing the exhaust pressure measured by the exhaust pressure sensor with a predetermined exhaust pressure determination value includes the following determination methods and determination methods based on a combination thereof. May be determined using the exhaust pressure and a predetermined exhaust pressure determination value.

One of them is to compare the exhaust pressure Pe measured by an exhaust pressure sensor provided on the upstream side of the filter with a predetermined exhaust pressure determination value Pes, and to determine the measured exhaust pressure Pe as a predetermined exhaust pressure determination value. When the number exceeds Pes, the reproducing operation is started.

The other is a differential pressure ΔPe = P1−P1 between an exhaust pressure P1 measured by an exhaust pressure sensor provided on the upstream side of the filter and an exhaust pressure P2 measured by an exhaust pressure sensor provided on the downstream side of the filter. P2 and a predetermined exhaust pressure determination value ΔPe
The regeneration operation is started when s is compared and the measured exhaust pressure ΔPe exceeds a predetermined exhaust pressure determination value ΔPes.

Further, instead of the differential pressure ΔPe, the pressure ratio Re =
By comparing P1 / P2 with a predetermined pressure ratio determination value Res,
When the measured pressure ratio Re exceeds a predetermined pressure ratio determination value Res, there is also a determination method of starting a regeneration operation.

2) In the above DPF device, the regeneration control means calculates an ash amount accumulated in the filter in the engine operating state from the engine torque and the engine speed, and accumulates the calculated ash amount. And calculating the ash cumulative estimate.

When calculating the ash amount Ash in which the unburned ash of the leaked lubricating oil in the operating state of the engine accumulates and accumulates on the filter from the engine torque Q and the engine rotational speed Ne, an experiment must be performed beforehand. And the relationship between the engine torque Q and the engine rotation speed Ne obtained by the calculation and the ash amount Ash accumulated in the filter in the operating state of the engine are obtained, and the map data Mash (Q, Ne) and The function fast (Q,
Ne) and use this.

The amount of the ash can be obtained by experiments and calculations of the amount of the lubricating oil consumed depending on the operating state of the engine. Further, the ash amount of about 8 g to 10 g is generated per liter of the lubricating oil. The amount of increase in exhaust pressure due to the amount of clogging of the filter is converted from the ash amount to obtain map data Mash (Q, Ne).
And the function fast (Q, Ne) are obtained.

3) In the above-mentioned DPF device, the regeneration control means calculates an exhaust pressure coefficient corresponding to the ash accumulated estimated value, and multiplies the exhaust pressure coefficient by a reference determination value to obtain a value. It is configured to correct the exhaust pressure determination value.

That is, the ash accumulated estimated value SAsh = Σ
The exhaust pressure coefficient α1 corresponding to (Ash × Δt) is calculated,
This exhaust pressure coefficient α1 is used as a reference determination value ΔPe0, Pe0, Re.
0 multiplied by 0, α1 × ΔPe0, α1 × Pe0, α
Correction is made by replacing each determination value ΔPes, Pes, Res with 1 × Re0.

4) In the above DPF device, the regeneration control means uses the engine torque and the engine speed when the exhaust pressure sensor measures the exhaust pressure for judging the regeneration start timing, and determines the reference. It is configured to calculate a value.

This reference determination value ΔPe0, Pe0, Re0
In the calculation of the engine torque Q and the engine speed Ne, reference determination values ΔPe0, Pe0, Re0 for determining the regeneration start timing related to the operating state of the engine are obtained in advance by experiments and calculations, Data MΔpe0
(Q, Ne), Mpe0 (Q, Ne), Mre0
(Q, Ne) and the function fΔpe0 (Q, Ne), fpe
0 (Q, Ne) and fre0 (Q, Ne)
Use this.

Then, the regeneration control method of the particulate filter device (DPF device) is configured as follows.

1) A filter for trapping particulate matter in exhaust gas of a diesel engine, an exhaust pressure sensor provided in an exhaust passage, and an exhaust pressure measured by the exhaust pressure sensor and a predetermined exhaust pressure determination value. According to the result of the comparison, the regeneration operation of the filter is started, and the particulate matter collected by the filter is removed by combustion or a chemical reaction using a catalyst to regenerate the filter. In the filter device, the ash leaked into the exhaust gas estimates the ash accumulation amount accumulated in the filter, and corrects the exhaust pressure determination value for determining the start of the regeneration operation based on the ash accumulation estimated value. Be composed.

2) In the above-described regeneration control method of the DPF device, the amount of ash accumulated in the filter in the engine operating state is calculated from the engine torque and the engine speed, and the calculated ash amount is accumulated. And calculating the ash cumulative estimate.

3) In the regeneration control method of the DPF device, the exhaust pressure coefficient corresponding to the ash cumulative estimation value is calculated, and the exhaust pressure coefficient is multiplied by a reference determination value to obtain a value obtained by multiplying the exhaust pressure coefficient by a reference determination value.
It is configured to correct the exhaust pressure determination value.

4) In the regeneration control method for the DPF device described above, the reference determination value is obtained from the engine torque and the engine speed when the exhaust pressure for measuring the regeneration start timing is measured by the exhaust pressure sensor. It is configured to calculate.

According to the DPF device and the regeneration control method of the above configuration, the following operation and effect can be obtained.

1) While estimating the state of accumulation and accumulation of unburned ash of engine lubricating oil on the filter, the exhaust pressure used for judging the start of the regeneration operation is calculated based on the estimated value of accumulated lubricating oil (calculated accumulation value). Since the judgment value has been corrected, the effect on the exhaust pressure due to the accumulation of unburned ash of the lubricating oil leaking into the exhaust gas from the engine cylinder in the filter is reflected in the judgment of the regeneration start timing. As a result, the determination of the reproduction start time is always performed appropriately.

2) The ash stored in the filter from the engine torque and the engine speed using the relationship between the engine torque, the engine speed and the ash accumulation amount, which is obtained in advance through experiments and calculations. By calculating the amount and accumulating the ash amount to calculate the ash accumulated estimated value, the ash accumulated estimated value can be accurately estimated by a simple algorithm.

3) In addition, the correction of the exhaust pressure determination value is corrected to a value obtained by calculating an exhaust pressure coefficient corresponding to the ash cumulative estimation value and multiplying the exhaust pressure coefficient by the reference determination value. The calculation for reflecting the influence of the oil on the determination at the start of the regeneration is a very simple calculation.

4) Further, using the relationship between the engine torque and the engine speed and the reference determination value in the operating state of the engine, which has been obtained in advance by experiments, calculations, and the like, the regeneration start timing is determined. When the exhaust pressure is measured, a reference determination value is calculated from the engine torque and the engine speed, and an exhaust pressure determination value is calculated from the reference determination value. Values can be compared between engines with the same operating condition, and differences in exhaust pressure due to differences in engine operating conditions are eliminated, making the decision at the start of regeneration operation more precise and more appropriate .

[0040]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A diesel particulate filter (hereinafter referred to as DPF) according to an embodiment of the present invention will be described below.
Will be described with reference to the drawings.

[Configuration of DPF Apparatus] FIG. 1 shows the configuration of a DPF apparatus 1 according to this embodiment. This DPF device 1
Is a continuous regeneration type DPF device, which is provided in the exhaust passage 2 of the engine E and provided with an oxidation catalyst 3 and a filter 4 with a catalyst from the upstream side.

For the purpose of controlling the regeneration of the catalyst-equipped filter 4, a first exhaust pressure sensor 51 is provided on the exhaust inlet side of the oxidation catalyst 3.
However, a second exhaust pressure sensor 52 is provided on the exhaust outlet side of the filter with catalyst 4.

The output values P1 and P2 of these sensors are used to control the overall operation of the engine and to control the regeneration of the filter with catalyst 4 and to control the regeneration of the engine. The fuel injection device 6 of the engine E is controlled by a control signal input to the engine control unit 5 and output from the control device 5.

The oxidation catalyst 3 is formed by supporting an oxidation catalyst such as platinum (Pt) / γ-alumina on a carrier such as a porous ceramic honeycomb structure. Monolith honeycomb type wall flow type filter in which the inlet and outlet of the high quality ceramic honeycomb channel are alternately plugged, and a felt-like filter in which inorganic fibers such as alumina are randomly laminated are formed. Is formed by supporting a catalyst such as Pt / γ alumina.

Then, the filter of the filter with catalyst 4 is
When the monolith honeycomb type wall flow type is adopted, the particulate matter in the exhaust gas G (hereinafter referred to as PM)
Is trapped by a porous ceramic wall, and when a fiber filter type is adopted, PM is trapped by the inorganic fibers of the filter.

[Regeneration Control Method] Next, the DPF having this configuration
A reproduction control method in the device 1 will be described.

This reproduction control method is implemented by a reproduction control means 50 formed by a control program mounted on the control device 5 or an input / output device, and the start of the reproduction operation is determined as shown in FIG. This is performed according to the determination flow at the start of the reproduction operation.

For ease of explanation, the illustrated determination flow at the start of the regeneration operation is performed in parallel with the control flow of the engine E (not shown) and the correction flow of the exhaust pressure determination value as shown in FIG. The regenerative pressure judgment value ΔPes for judging the start of the regenerating operation, which is executed in the correction flow of the evacuation pressure judgment value of FIG. For example, an instruction to start a regeneration mode operation, which is a regeneration operation, is output.

That is, during the operation control of the engine E, this flow is repeatedly called and executed at regular time intervals together with the flow of correcting the exhaust pressure determination value. The regeneration operation of the filter with catalyst 4 is substantially terminated.

In the determination flow at the start of the regeneration operation shown in FIG. 2, when started, the exhaust pressure measured by the first exhaust pressure sensor 51 provided upstream of the filter 4 for determining the start of the regeneration operation in step S11. P1 and the exhaust pressure P2 measured by the second exhaust pressure sensor 52 provided on the downstream side of the filter 4 are input, and in step S12, the differential pressure ΔP
e = P1−P2 is calculated, and in step S13, the exhaust pressure determination value ΔPes for determining the start of the regeneration operation corrected in the exhaust pressure determination value correction flow of FIG. 3 is input.

Then, in step S14, the differential pressure ΔPe is compared with a predetermined exhaust pressure determination value ΔPes, and when the measured exhaust pressure ΔPe exceeds the predetermined exhaust pressure determination value ΔPes,
In step S15, the process returns after instructing the start of the regeneration mode operation, and otherwise returns as it is.

FIG. 1 shows the operation of the regeneration mode operation.
In the DPF device 1, in the fuel injection control, the main injection is delayed (retarded) or further post-injection (post-injection) is performed to raise the exhaust gas temperature, activate the oxidation catalyst 3, and The PM is removed by a chemical reaction of the catalyst carried on the filter 4 with the catalyst, and the filter 4 with the catalyst is regenerated.

[Method of Correcting Exhaust Pressure Judgment Value] In the present invention, the exhaust pressure judgment value ΔPes for judging the start of the regenerating operation used in the above is used as the value of the lubricating oil of the engine E leaked into the exhaust gas G. The remaining unburned ash is configured to estimate an accumulated amount of the ash accumulated in the filter, and to correct and correct the exhaust pressure determination value based on the ash accumulated estimated value.

This correction and correction are performed according to a correction flow of the exhaust pressure determination value as illustrated in FIG.

When this flow starts, first, in step S21, a torque Q indicating the operating state of the engine E is set.
And the engine speed Ne are input, and the next step S22
From the torque Q and the engine speed Ne, the ash amount Ash in which the ash is accumulated in the filter 4 within the unit time (Δt) is calculated by using the previously input map data Mash (Q, Ne) as shown in FIG. ).

The value of the map data Mash (Q, Ne) is determined in advance by calculating the ash amount Ash accumulated in the catalyst-equipped filter 4 corresponding to the torque Q and the engine speed Ne by experiments and calculations. This is input to the control means 50 in advance. In addition, instead of map data, Q
Fash (Q, Ne) for calculating As from Ne and Ne
May be input to the reproduction control means 50 in advance.

In step S23, the calculated ash amount Ash is added to the ash accumulation estimated value SAsh (SAsh = SAsh + Ash × Δt).

That is, the reproduction control means 50 controls the engine E
From the torque Q and the engine speed Ne, the ash amount Ash accumulated in the catalyst-equipped filter 4 in the operating state of the engine E is calculated, and the calculated ash amount Ash is calculated.
Is accumulated and the ash accumulated estimated value SAsh = Σ (A
sh × Δt).

Then, in step S24, as shown in FIG. 5, the exhaust pressure coefficient α1 corresponding to the ash accumulated estimated value SAsh is calculated. In step S25, the exhaust pressure sensors 51 and 52 determine the regeneration start timing. Exhaust pressure P1, P
2, the reference determination value ΔPe0 in the operating state of the engine E is obtained from the engine torque Q and the engine speed Ne.

In the calculation of the reference determination value ΔPe0, the reference determination value ΔPe0 (Q, Ne) for determining the start timing of the regeneration operation related to the operating state of the engine with the engine torque Q and the engine speed Ne is set in advance. It is obtained through experiments and calculations, and this is calculated using map data MΔp as shown in FIG.
It is prepared and used as e0 (Q, Ne) and function fΔpe0 (Q, Ne).

Then, in step S26, the exhaust pressure determination value Δ
The Pes is corrected (corrected).
A value α1 × ΔPe obtained by multiplying the reference judgment value ΔPe0 by 1
This is performed by replacing the exhaust pressure determination value ΔPes with 0. That is, ΔPes = α1 × ΔPe0.

Finally, in step S26, the corrected exhaust pressure determination value ΔPes is output, and the routine returns.

[Effects] According to the DPF device 1 having the above-described configuration and the regeneration control method thereof, the following effects can be obtained.

While estimating the state of accumulation of unburned ash of the lubricating oil of the engine E in the catalyst-equipped filter 4, the exhaust pressure judgment value ΔPes used to judge the start of the regeneration operation is corrected based on the estimated ash accumulation value SAsh. Therefore, the influence on the exhaust pressures P1 and P2 due to the accumulation of the unburned ash of the lubricating oil leaking into the exhaust gas G from the combustion chamber of the engine E in the filter with catalyst 4 is reflected in the determination of the regeneration start timing. Can be. As a result, it is possible to always appropriately determine the reproduction start time.

Using the relationship between the engine torque Q, the engine speed Ne, and the ash amount Ash accumulated or deposited on the catalyzed filter 4 in the engine operating state, the ash amount accumulated in the catalyzed filter 4 is calculated. As
By calculating h, performing cumulative calculation, and calculating the cumulative estimated value SAsh, the cumulative amount of ash can be accurately estimated with a simple algorithm.

The correction of the exhaust pressure determination value ΔPes is performed by a simple calculation of correcting the exhaust pressure coefficient α1 corresponding to the ash cumulative estimated value SAsh to a value α1 × ΔPe0 obtained by multiplying the reference determination value ΔPe0. Therefore, a calculation for reflecting the influence of the ash of the lubricating oil on the determination at the time of starting the regeneration can be performed by a very simple calculation.

Further, since the reference determination value ΔPe0 is calculated from the engine torque Q and the engine speed Ne, which are obtained in advance through experiments and calculations, the measured exhaust pressures P1 and P2 are compared with the exhaust pressure determination for comparison. Since the value ΔPes can be compared between the same engine operation states, the difference between the exhaust pressures P1 and P2 due to the difference between the engine operation states can be eliminated, and the determination at the start of regeneration can be performed more finely. .

[Other Embodiments] The determination at the start of the regenerating operation is not limited to this embodiment, and the exhaust pressure Pe = Pe measured by the exhaust pressure sensor 51 provided on the upstream side of the filter 4 may be used. By comparing P1 with a predetermined exhaust pressure determination value Pes, the measured exhaust pressure Pe becomes a predetermined exhaust pressure determination value Pes.
There is also a DPF device that starts a regenerating operation when the number exceeds the limit, and a regenerating control method thereof.

The pressure ratio Re = P1 / 1 of the exhaust pressure P1 measured by the exhaust pressure sensor 51 provided on the upstream side of the filter 4 and the exhaust pressure P2 measured by the exhaust pressure sensor 52 provided on the downstream side of the filter 4. P2 and a predetermined pressure ratio determination value Res, and when the measured pressure ratio Re exceeds the predetermined pressure ratio determination value Res, a DPF device and a regeneration control method for starting regeneration mode operation. There is also.

There are also a DPF device and a regeneration control method thereof in which some of these determinations are combined.
The PF device and the regeneration control method include not only the DPF device and the regeneration control method, but also a DPF device that uses the exhaust pressure to determine the start of the regeneration operation and the regeneration control method.

[0071]

As described above, according to the diesel particulate filter device (DPF) device and the regeneration control method of the present invention, the state of accumulation and accumulation of ash generated from lubricating oil on the filter is estimated. Since the exhaust pressure determination value relating to the exhaust pressure used for determining the start of regeneration is corrected or corrected based on the estimated value of the ash accumulation, the regeneration operation at the start of the regeneration operation in consideration of the effect of the filter clogging of the ash generated from the lubricating oil is considered. You can judge.

As a result, even if the running distance of a diesel engine vehicle equipped with this DPF device increases, the DPF
Since the start time of regeneration of the filter of the device can be properly determined, the PM can be efficiently prevented while preventing the filter from being clogged.
Can be removed and run.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a diesel particulate filter device according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a determination flow at the time of starting a regeneration operation of a diesel particulate filter device.

FIG. 3 is a flowchart illustrating a correction flow of an exhaust pressure determination value.

FIG. 4 is a schematic diagram of map data showing a relationship between an engine torque, an engine speed, and an amount of ash accumulated in a filter per unit time.

FIG. 5 is a diagram showing a relationship between an estimated ash value and an exhaust pressure coefficient.

FIG. 6 is a schematic diagram of map data showing a relationship between an engine torque, an engine speed, and a reference determination value for determining a regeneration start time.

[Explanation of symbols]

 Reference Signs List 1 continuous regeneration type particulate filter device 2 exhaust passage 3 oxidation catalyst 4 filter with catalyst 5 control device (ECU) 6 fuel injection device 50 regeneration control means 51 first exhaust pressure sensor 52 second exhaust pressure sensor E diesel engine G exhaust gas Ne Engine speed Q Engine torque Ash Ash amount Accumulated amount of Ash Ash α1 Exhaust pressure coefficient P1 Measured upstream exhaust pressure P2 Measured downstream exhaust pressure ΔPe0, Pe0, Re0 Reference determination value ΔPes, Pes, Res Pressure judgment value

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tsuneo Suzuki Eighth Tsurana, Fujisawa City, Kanagawa Prefecture Isuzu Motors Fujisawa Plant Co., Ltd. (72) Inventor Naofumi Ochi 8 Tsuchiya, Fujisawa City, Kanagawa Prefecture Isuzu Motors Fujisawa Plant Co., Ltd. (72) Inventor Masashi Gabe 8 Tsuchiya, Fujisawa City, Kanagawa Prefecture Isuzu Motors Fujisawa Plant F-term (reference) 3G090 AA03 BA01 CA01 CB00 DA04 EA02 4D058 JA32 JB06 JB28 MA44 MA51 MA54 MA60 SA08 TA06

Claims (8)

[Claims] 1. A filter for collecting particulate matter in exhaust gas of a diesel engine, an exhaust pressure sensor provided in an exhaust passage, and an exhaust pressure measured by the exhaust pressure sensor and a predetermined exhaust pressure determination value. According to the result of the comparison, the regeneration operation of the filter is started, and the particulate matter collected by the filter is removed by combustion or a chemical reaction using a catalyst to regenerate the filter. In the filter device, the regeneration control unit estimates an ash accumulation amount in which ash leaked into exhaust gas is accumulated in the filter, and the exhaust pressure determination for determining a start of a regeneration operation based on the ash accumulation estimated value. A diesel particulate filter device configured to modify a value. 2. The regeneration control means calculates an ash amount accumulated in the filter in an engine operating state from an engine torque and an engine speed, and accumulates the calculated ash amount to calculate the ash amount. 2. The diesel particulate filter device according to claim 1, wherein an accumulated estimated value is calculated. 3. The regeneration control means calculates an exhaust pressure coefficient corresponding to the ash cumulative estimation value, and corrects the exhaust pressure determination value to a value obtained by multiplying the exhaust pressure coefficient by a reference determination value. The diesel particulate filter device according to claim 1 or 2, wherein: 4. The method according to claim 1, wherein the regeneration control means measures an exhaust pressure for determining a regeneration start timing with the exhaust pressure sensor.
The diesel particulate filter device according to claim 3, wherein the reference determination value is calculated from an engine torque and an engine speed. 5. A filter for collecting particulate matter in exhaust gas of a diesel engine, an exhaust pressure sensor provided in an exhaust passage, and an exhaust pressure measured by the exhaust pressure sensor and a predetermined exhaust pressure determination value. According to the result of the comparison, the regeneration operation of the filter is started, and the particulate matter collected by the filter is removed by combustion or a chemical reaction using a catalyst to regenerate the filter. In the filter device, ash leaked into the exhaust gas estimates an ash accumulation amount accumulated in the filter, and corrects the exhaust pressure determination value for determining regeneration operation start based on the ash accumulation estimated value. A regeneration control method for a diesel particulate filter device. 6. An ash amount to be accumulated in the filter in an engine operating state is calculated from an engine torque and an engine speed, and the calculated ash amount is cumulatively calculated to calculate the ash cumulative estimation value. The regeneration control method for a diesel particulate filter device according to claim 5, wherein the calculation is performed. 7. An exhaust pressure coefficient corresponding to the ash cumulative estimation value is calculated, and the exhaust pressure determination value is corrected to a value obtained by multiplying the exhaust pressure coefficient by a reference determination value. A regeneration control method for a diesel particulate filter device according to claim 5. 8. The reference determination value is calculated from an engine torque and an engine speed when an exhaust pressure for determining a regeneration start timing is measured by the exhaust pressure sensor. A regeneration control method for the diesel particulate filter device described in the above.