JPH07139331A - Filter regenerator for internal combustion engine - Google Patents

Abstract

PURPOSE:To precisely detect quantity of particulates captured by a filter so as to improve regeneration efficiency by estimating temperature of the filter so as to correct microwave quantity, when the particulates are burnt by using microwave so as to regenerate the filter. CONSTITUTION:A heating space 15 is formed in an exhaust pipe 13 for an internal combustion engine 14 and a filter 16 for capturing particulates in exhaust gas is arranged therein. Microwave from a microwave generator 17 is supplied to the heating space 15 via a wave guide distribution means 18, etc., and the captured particulates are burnt so as to regenerate the filter 16. Burning acceleration air for accelerating burning of the particulates is supplied to the heating space 15 from an air supply means 32. And a microwave detection means 36 and an air temperature detection means 37 are arranged in the inside and the outside of the heating space 15. The drive power supply 27 of the microwave generation means 17 and the air supply means 32 are controlled by a control means 38 based on respective detection signals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for regenerating a filter for an internal combustion engine which collects particulates (particulate matter) contained in exhaust gas discharged from a diesel engine.

[0002]

2. Description of the Related Art With respect to global environmental protection, measures against global warming, that is, CO2 reduction measures have been greatly emphasized today, but measures against acid rain causing deforestation cannot be ignored. Acid rain is a natural phenomenon caused by air pollutants such as sulfur oxides and nitrogen oxides as pollutants. In recent years, emission control of such air pollutants in countries around the world has been fixed sources such as co-generation and automobiles. There is a move to be strengthened against mobile sources such as. At the same time as environmental pollution to an unspecified number of people, environmental pollution in the work environment is also a major issue, and the solution to the problem is becoming apparent.

Among the mobile sources, a vehicle driven by a diesel engine is required to suppress nitrogen oxides and at the same time suppress particulate emissions.

As a countermeasure against this restraint, the engine side is trying to restrain the emission of nitrogen oxides, and the particulate restraint is being post-treated. This post-treatment device has a filter for collecting particulates.

However, if the particulates are continuously collected, the filter will be clogged and the flow of the exhaust gas will be deteriorated, leading to a reduction in engine output or an engine stop.

[0006] Therefore, although technical development for regenerating the trapping ability of the filter is currently underway all over the world,
Ensuring durability is a major practical issue.

It is known that particulates burn from about 600 ° C. As a means for generating energy to raise the particulates to this high temperature range,
A burner method, an electric heater method, a microwave method, etc. are considered.

The inventors of the present invention have developed a microwave filter regeneration device in consideration of good temperature rising efficiency, safety, easy device configuration, good regeneration controllability, and the like.

An example of a filter reproducing device using the microwave system is disclosed in Japanese Patent Laid-Open No. 61-11416. The device disclosed in this publication is shown in FIG. In the figure, 1 is an engine, 2 is an exhaust pipe, 3 is a filter, 4
Is a microwave heating space, 5 is a magnetron which is a microwave generating means, 6 is a microwave leakage preventing means which limits the microwave heating space 4, and 7 is a microwave which is generated by the magnetron 5 and is transmitted to the microwave heating space 4. Microwave supply paths 8, 8 and 9 are detection means provided in the microwave supply path 7 for detecting an incident wave to the microwave heating space 4 and a reflected wave from the heating space, and 10 is a control device which is an incident wave of the microwave. A device for controlling the operation of the magnetron 5 based on the signals of the reflected wave and the engine operating time.
Reference numeral 11 is a drive power source for the magnetron 5, and 12 is a muffler.

In the above structure, the particulates contained in the exhaust gas of the engine are collected by the filter 3 while flowing through the filter 3. The amount of particulates collected by the filter 3 increases with the passage of time, but in this process the output signal of the controller 10 causes the magnetron 5
Is operated at a constant cycle, and changes in the microwave characteristics of the entire heating space 4 are measured based on the signals of the incident wave and the reflected wave. If the amount of the particulates collected by the filter 3 becomes too large, the load on the engine will increase and the engine will stop in the worst case. Therefore, it is necessary to remove the particulates at an appropriate time. The microwave characteristic of the microwave heating space 4 corresponding to the appropriate time, that is, the time of depositing the appropriate amount of particulates is obtained in advance, and the signal level corresponding to the characteristic is stored in the controller 10.

When the detected signal level reaches the stored predetermined level, the output of the magnetron 5 is increased to dielectrically heat the particulates trapped in the filter 3 and the particulates are trapped by the oxygen contained in the exhaust gas. It is burned and removed. As a result, the particulates collected in the filter 3 are removed, so that the filter 3 can again collect an appropriate amount of particulates.

[0012]

However, the conventional device described above has two problems. One is that it is difficult to perform microwave heating regeneration that can prevent mechanical damage of the filter because the detection accuracy of the amount of particulates collected by the filter is poor as described later. The second is that it is difficult to conclude that the features of microwave heating regeneration are utilized because the specific regeneration method in microwave heating regeneration is unknown.

The first problem is that the detection of the amount of collection based on the incident wave voltage and the reflected wave voltage is a scalar quantity, and the collection quantity is one-to-one with respect to the relationship between the detection quantity and the collection quantity. It is difficult to deal with a wide collection area because it is necessary to limit the quantity range. At least the vector quantity needs to be detected.
Furthermore, the temperature of the filter changes due to the flow of exhaust gas, but this change in the filter temperature changes the signal as if the apparent collection amount increased as the temperature increased in detection of the collection amount using microwaves. give. This is due to the increased dielectric loss of the filter itself.

Regarding the second problem, the heating means using microwaves can selectively heat the particulate itself when compared with other conventional heating means. Moreover, it is possible to heat the inside of the filter without the need for a gas flow. This unique property of microwave heating makes it possible to construct a new heating control content with respect to the regeneration control of other conventional heating methods, but the specific control content is not disclosed. .

The present invention solves the above problems, and an object of the present invention is to provide a structure for utilizing the characteristics of microwaves to realize filter regeneration control of practical value.

[0016]

As a means for achieving the above object, the present invention provides a microwave generating means, a drive power source section for operating the microwave generating means, and a microwave generated by the microwave generating means. A heating space for supplying power, a filter provided in the heating space for collecting particulates contained in exhaust gas discharged from the internal combustion engine, an air supply means for supplying air to be passed through the filter, and a micro in the heating space. It comprises a microwave detection means for detecting the amount of waves and a temperature detection means for detecting the temperature of the exhaust gas or air which is provided outside the heating space and flows through the filter.

Further, the microwave detecting means is constructed to detect the microwave quantity of the exhaust gas non-flowing space in the heating space, and the temperature detecting means detects the exhaust gas temperature during operation of the internal combustion engine, While the internal combustion engine is stopped, the air supply means is operated to detect the air temperature after passing through the filter.

Further, a control unit for inputting the temperature detection signal and the microwave detection signal is provided, and the operation of the drive power supply unit and the air supply unit for operating the microwave generation means is controlled based on the instruction of the control section. The command of the control unit is composed of a command for extracting and determining predetermined control contents stored in the storage unit based on the input signal and a command for determining based on the temporal change amount of the input signal.

Furthermore, the preheating period of the particulates by the microwave is defined by a predetermined time stored in the storage section which is determined based on the temperature detection signal and the microwave detection signal, and the temperature detection signal or the microwave detection signal is used. The completion of burning of particulates is defined based on the amount of change over time.

[0020]

In the above construction, the temperature detecting means is provided outside the heating space to eliminate the influence of the microwave of the temperature detecting portion. Further, by disposing the temperature detection signal in the passage space where the temperature of the filter can be estimated equivalently, the temperature of the microwave detection signal can be corrected based on the temperature signal.

Further, the microwave detecting means is provided at a position for detecting the amount of microwaves in the exhaust gas non-flowing space of the heating space, so that it is isolated from exhaust gas contamination and the detection performance is guaranteed. Furthermore, by detecting the microwave amount information near a specific position in the heating space, the intensity distribution information of the electromagnetic field generated in the heating space is taken into consideration, so that it is possible to detect the vector amount even in a single detection. ing.

The temperature detecting means is provided at a position where the temperature of the exhaust gas can be detected while the internal combustion engine is operating and the air supply means is operated to detect the air temperature after passing through the filter when the internal combustion engine is stopped. Therefore, the temperature of the filter can always be detected independently of the operation of the internal combustion engine. As a result, the regeneration of the filter can be executed at free timing independently of the operation of the internal combustion engine.

Further, the apparatus of the present invention is provided with a storage section in which predetermined control command information is stored. This stored information forms a matrix of control commands determined in advance using the filter temperature and the microwave detection amount as parameters. From the data group of this matrix, time data that determines the optimum preheating period in light of the filter state at the start of regeneration is selected. As a result, the optimum microwave heating is defined in the previous stage in which the combustion of particulates is effectively advanced.

Further, the combustion of the particulates progresses through the above-mentioned preheating period, but the temperature information or the microwave after passing through the filter of the air supplied from the air supply means for promoting the combustion of the particulates in this combustion period. Based on the amount of change over time in the detection signal, the optimum progress of combustion and the regulation of combustion completion are executed, and the optimum regeneration control by microwave heating prevents mechanical damage to the filter and traps particulates in the filter. Guaranteed durability of performance.

[0025]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1 and FIG. 2, 13 is an exhaust pipe for discharging the exhaust gas of the internal combustion engine (diesel engine) 14, 15 is a heating space provided in the middle of the exhaust pipe 13, and 16 is an exhaust gas housed in the heating space. A filter having a honeycomb structure for collecting particulates contained in the exhaust gas while the gas passes therethrough, 17 is a microwave generation means for generating microwaves for supplying electric power to a heating space for dielectrically heating the particulates, 18 Is a waveguide distributing means composed of two divisions of the microwave generated by the microwave generating means 17, and 19 and 20 are annular waveguides 21 in which each of the two divided microwaves is arranged on the outer peripheral portion of the heating space 15. , 22 are coaxial transmission means, 23 and 24 are coaxial waveguide conversion antennas, and 25 and 26 are heating space 15 and annular waveguides 21 and 22.
Microwave power feeding means for feeding microwaves into the heating space 15 is provided at a predetermined position of the tube wall forming the and, and 27 is a drive power source section of the microwave generating means 17. In addition, the microwave generation means 17, the driving power supply section 27 and the distribution means 1
8 is integrally stored in a storage unit 28 formed of a metal housing.

An exhaust gas switching valve 29 allows the exhaust gas discharged from the internal combustion engine 14 to flow through the filter 16 or the exhaust branch pipe 30 when the filter 16 is regenerated. 31 is a muffler. The muffler 31 can be configured to include an oxidation catalyst, for example. Reference numeral 32 is an air supply means for air (hereinafter referred to as auxiliary combustion air) for promoting the combustion of particulates, and 33 and 3.
Reference numeral 4 denotes an auxiliary combustion air flow control valve, which controls these two valves to allow auxiliary combustion air to flow through the filter 16 during filter regeneration. Reference numeral 35 is a discharge pipe for the auxiliary combustion air flowing through the filter 16. Reference numeral 36 is a microwave detecting means provided in the exhaust gas non-flowing space of the filter 16 and detecting the amount of microwaves existing in the vicinity of this installation space. 37 is a temperature detecting means, which is arranged between the auxiliary combustion air flow control valve 34 and the exhaust pipe 13. The detection signals of the microwave detection means 36 and the temperature detection means 37 are input to the control unit 38. Although only one microwave detecting means 36 is shown, a plurality of microwave detecting means 36 may be provided. When a plurality of filters are provided, it is effective to dispose the filters in parallel with the exhaust gas flow direction of the filter 16. The operation signal of the internal combustion engine 14 is also input to the control unit 38. Reference numeral 39 denotes a storage unit, the details of which will be described later.

The heating space 15 has a punching hole structure or a honeycomb structure (in the embodiment, a cross-shaped honeycomb structure is shown, but one shape or a US shape can be selected depending on the size of the pipe inner diameter). The space for substantially confining the microwave is limited by the microwave shielding means 40, 41 including the above. Reference numeral 42 denotes a heat insulating material provided between the outer periphery of the filter 16 and the filter support tube 43, which also serves as a filter support. Both ends (with respect to the exhaust gas flow direction) of the heat insulating material 42 are separated from the exhaust gas by a metal plate 44 and a sealing material 45. In addition, the metal plate 44 is
The filter support tube 43 is fitted and assembled on both ends of the filter support tube 43, and is integrally formed with a flange structure 46 that allows the filter section to be attached and detached. The flange structure 46 is screw-assembled with the flange structure on the heating space side. In the case of FIG. 2, the flange structure on the heating space side is the side wall 47 of the annular waveguide 21. A screw 48 is welded and assembled to the side wall 47. The filter support tube 43 is assembled with the screw 48 and the nut 49 to form the heating space 15.

Next, the structure around the annular waveguides 21 and 22 will be described. The two configurations are the same.

The annular waveguide 21 is arranged so as to surround the periphery of the heating space 15, and its waveguide length is set to an appropriate length. At one end of the annular waveguide 21 in the waveguide length direction,
The coaxial waveguide converting antenna 23 is arranged, and the feeding means 25 is arranged on the other end side. Further, the power feeding means 25 and 26 are arranged to face each other, and microwaves having a phase difference of 180 degrees are fed to the heating space 15 from the power feeding means 25 and 26. With this power feeding configuration, the excitation mode of the TE21p mode or the TE10p mode is generated in the heating space 15 depending on the pipe inner diameter of the heating space.

The heating space 15 is required to uniformly heat the particulates deposited on the filter as much as possible in order to suppress generation of thermal stress during particulate combustion and prevent mechanical damage to the filter. To be done. For this requirement, the inventors have tested various excitation modes that can be formed in the heating space. The choice of excitation mode is also limited by the filter volume used.
Further, there is a limitation depending on the mounting configuration of the device. Although there are such system restrictions, it is important to attach importance to environment resistance as a basic selection index. Based on this index, the present inventors set TE as the excitation mode in the heating space.
You have selected a mode. The present invention is configured on the basis of the experimental results that it is important to provide a plurality of power feed units and optimize the phase difference between the power feed signals in order to form a more uniform heating mode in the TE mode. It will be understood from the above that the embodiment of the present invention presents a configuration with two power supplies, but this is not limited to two. In the case of the two power feeding units shown in the embodiment, which is one of the plurality of power feeding units, the phase difference between the power feeding units is set to 1
The present inventors have confirmed through experiments that the selection of 80 degrees is effective in promoting uniform heating. Also, the above T
Note the advantages of E-mode selection.

The TE mode is a state in which the microwave electric field is perpendicular to the flow direction of the exhaust gas in the case of this device. This makes it possible to effectively feed microwaves or extract signals from the lateral direction of the exhaust pipe (such as the microwave detecting means in the embodiment).

Further, the microwave generating means 17, the drive power source section 27 and the microwave distributing means 18 are integrally housed in a metal casing 28. The centralized configuration of the elements relating to the generation of microwaves makes it possible to effectively prevent unnecessary radiation, centralize high-voltage wiring, and centralize the cooling configuration of heat-generating components. This configuration is a concept in which the microwave generation unit and the microwave action unit are separated from each other, and it is possible to dramatically increase the degree of freedom in mounting the device.

Further, the concept of distributing and transmitting the microwave output power makes it possible to use a general-purpose coaxial transmission means.

Next, the structure around the microwave detecting means 36 will be described. In the heating space 15, the heating space 15 and the microwave feeding means 25 and 26 are configured so that the TE mode is excited as described above. The detection unit of the microwave detection means 36 is configured to detect a desired microwave corresponding to this excitation mode. The structure of the detector is such that the center conductor of the coaxial cable is projected into the heating space 15 by a predetermined length, and the center conductor of the detector is coupled to the microwave electric field in the vicinity of the microwave detecting means in the heating space.
It should be noted that the heat insulating material 42 around the detecting portion can be easily attached by appropriately removing the heat insulating material 42.

This form of coupling is not limited to the above-mentioned contents, but may be a configuration utilizing a form of magnetic field coupling.
Importantly, considering the electromagnetic field distribution in the heating space 15,
It is to grasp how this electromagnetic field distribution changes according to the amount of particulates trapped in the filter. Then, the range of the amount of collected particulates in the filter 16 that is allowed in the regeneration device is stared at, and the amount of collected amount detection can be accurately extracted based on the detection signal over the entire range of the amount of collected amount. It is to select the detection position. As the position of the detector, a region corresponding to 1/4 of the wavelength of the standing wave in the excitation mode generated in the heating space is selected, and the optimum position is selected according to the desired allowable collection amount range. Depending on the selection of the detector mounting position, the detected signal gradually decreases with an increase in the collection amount, or takes a lower limit value or an upper limit value at a certain collection amount. The present invention can select any of the above-mentioned forms of change of the detection signal.

Next, the temperature detecting means 37 will be described in detail. As the detecting means, a thermistor whose electric resistance value greatly changes according to temperature or a thermocouple whose electric resistance value changes little can be used. A thermocouple is effective as the temperature detecting means for accurately detecting a wide range of temperatures. The temperature detecting means 37 has three functions. One is to provide the temperature information of the filter to detect the collected amount accurately, and the other is to detect the filter temperature at the start of filter regeneration and regulate the preheating time at regeneration to control the operation of the microwave heating means. The third is to grasp the particulate combustion state during regeneration and control the operation of the microwave heating means or the air supply means. For this function, the temperature detecting means 3 is located at a position where the temperature information of the filter can be detected both when the internal combustion engine is operating and when it is stopped.
7 are arranged. The detection position is a position where the exhaust gas is not directly exposed during the operation of the internal combustion engine, and corresponds to an air flow passage generated by the air supply means 32 for use during filter regeneration while the internal combustion engine is stopped. The location is selected. As a result, the temperature of the filter can be detected independently of the operating state of the internal combustion engine.

Next, the storage unit 39 will be described. The storage unit is composed of a semiconductor chip or a ROM card, and the data stored in the storage unit is predetermined information. The main part of the data stored in the storage unit is information relating to the definition of the preheating period during filter regeneration. This information is configured as a matrix of operation control content data in the preheating period of the microwave heating means, which uses the filter temperature and the microwave detection signal as variables. This data defines the heating time and heating power.

The present invention has the above-mentioned structure, and its main operation and action will be described. First, the operation of the entire apparatus will be described.

While the internal combustion engine 14 is operating, the drive power source section 27 of the microwave generating means 38 is set at a predetermined time interval.
To input the microwave detection signal and the filter temperature equivalent signal to the control unit 38. When the internal combustion engine 14 is stopped, the above signals can be input manually.
The determination of the operation / stop of the internal combustion engine uses, for example, a rotation speed signal of the internal combustion engine.

One of the controls of the control unit 38 is to determine the amount of particulates collected on the filter 16. The state of the collected amount can be notified. In addition, a value corresponding to the collection limit amount is stored in advance, the detected signal of the microwave detecting means is compared with the signal value stored in advance, and when the signal level stored in advance is reached, a signal prompting filter regeneration is generated. Can be emitted. Based on this signal, it is possible to automatically shift to the filter regeneration mode.

Another control of the control unit 38 is filter regeneration control. When regeneration is started, the regeneration start signal is detected by detecting the limit trapping amount and the regeneration start signal is manually input. Be classified when In either case, the filter temperature equivalent signal and the microwave detection signal are taken in at the initial stage of the regeneration and the stored data in the storage unit 39 is extracted to advance the preheating.

The exhaust gas emitted by the internal combustion engine 14 is usually
It flows through the exhaust pipe 13 and flows into the filter 16. The filter 16 is composed of a wall flow type honeycomb structure and has a function of collecting particulates contained in the exhaust gas. When the amount of particulates collected by the filter increases, the pressure loss of the filter increases, the load of the engine, which is an internal combustion engine, increases, and in the worst case, the engine stops.

Therefore, it is necessary to remove the particulates collected by the filter at an appropriate time. The process of heating and removing the particulates trapped in the filter is called filter regeneration. The main control contents in this filter regeneration will be described below with reference to FIGS. 3 and 4.

When the internal combustion engine is operating, the exhaust gas switching valve 29 is controlled so that the exhaust gas is discharged to the exhaust branch pipe 30.
Distribute to. The same applies when the internal combustion engine is stopped.
Further, the auxiliary combustion gas flow control valves 33 and 34 are controlled to a closed state and an open state, respectively. After this, the main filter regeneration control is executed.

In S100 (t = 0), the operation of the microwave generation means 17 is started, and the air supply means 32 is operated in S101. In S102, the air supply means 32 is operated until a predetermined time (t = t1). The air supplied from the air supply means 32 is discharged after passing through the filter 16 through the air flow pipe provided with the temperature detection means 37. Note that t1 is about 1 minute. When the time from the start of reproduction reaches t1, the process proceeds to S103. In S103, the temperature information detected by the temperature detecting means 37 at that time is fetched into the control unit 38. In S104, the microwave detection means 3
The microwave amount information in the heating space 15 detected by 6 is taken into the control unit 38. Then, in S105, the operation of the air supply means 32 is stopped. S106 and S107
At time t2, the control unit 38 stores the temperature information and the microwave amount information in the storage unit 39 based on the input temperature information and microwave amount information.
And the data value at time t3. The control unit 38 waits until the elapsed playback time reaches t2 (S108).

During this waiting time, the particulates deposited on the filter are quickly heated and raised in temperature. To explain the progress of this heating, the microwave generated by the microwave generating means 17 is divided into two powers by the E-plane T branch pipe 18 of the waveguide, and the phase difference between the respective divided signals becomes 180 degrees. The distributed microwaves are transmitted by coaxial transmission means 19, 20.
Is transmitted to the heating space 15 by the microwave power feeding means 25 and 26. In the heating space, TE mode excitation occurs. Corresponding to this excitation mode, filter 1
The particulates collected in 6 are dielectrically heated. During this period, the exhaust gas flow or the air flow passing through the filter is blocked, and the particulate temperature rapidly rises to a combustible temperature range. The temperature increase distribution at this time is a distribution inclined to the filter end face side where the microwave is radiated, but about a half region in the exhaust gas flow direction of the filter reaches the combustible temperature. This heating time is a so-called preheating time.

After that, the process proceeds to S109 and the air supply means 32
To operate. This operation time is t3 (S11
0). By this operation, the auxiliary combustion air that promotes the combustion of particulates is supplied to the filter 16, and the particulates that have reached the combustible temperature range reach the combustible temperature range by promoting the combustion and transferring the combustion heat. The particulates in the non-particulate deposition area are heated to promote the expansion of the combustion area. Further, the combustion region advances in the flow direction of the air flow due to the flow of the air flow. After forming this initial combustion state, the operation proceeds to S111, and the operation of the air supply means 32 is stopped. S111 to S11
The control for 7 is repeated until the reproduction elapsed time reaches t6. The control during this period is for ON-OFF control of the operation of the air supply means 32, and the ON time is t.
5, OFF time is defined as t4-t5. For the time parameters t4 and t5, predetermined values are used, but they may be varied based on temperature information or microwave amount information that changes with the progress of combustion. During such air supply control time, heating of the particulates that remains even during the time when air is not supplied is advanced by the microwaves, combustion is promoted along with the air supply, and the extinction of combustion does not occur. By this control, the particulates accumulated in the filter are gradually burned and removed.

When the time reaches t6, the process proceeds to S118. S
In 118 and S119, the temporal change of the temperature information detected by the temperature detecting means 37 is extracted. After determining that this temperature information has reached the maximum value, the process proceeds to S120.

In step S120, the microwave quantity information at that time is extracted. Based on this microwave quantity information,
It is possible to judge the quality of the particulate combustion removal state. Further, this determination result can be notified to the outside.

Then, in S121, the microwave generation means 1
The operation of 7 is stopped (t7). In S122 to S124, the operation of the air supply means 32 is stopped after the elapse of a predetermined time t9 determined in advance after the microwave is stopped (t8). The operation stop time of the air supply means can be determined at the timing when the level of the temperature detection signal becomes equal to or lower than a predetermined value, in addition to the timer control as described above.

After the above, the filter regeneration is completed, and thereafter, the valves 29, 33 and 34 are controlled to the initial state in which the exhaust gas is passed through the filter. Immediately after the filter regeneration is completed, the exhaust gas can flow into the filter 16 to collect the particulates.

As described above, the fundamental object of the present invention is to provide a filter regenerator of practical use that utilizes microwaves in a filter regenerator for an internal combustion engine. On the other hand, the present invention is a combination of unique ideas and techniques from both sides of the microwave generation part and the microwave action part, and the embodiment is not limited to the examples. For example, the microwave power supply may be provided on the exhaust gas upstream side of the filter.

[0054]

As described above, according to the filter regenerating apparatus for an internal combustion engine of the present invention, the following effects can be obtained.

(1) In a filter regenerator using microwaves as heating means, the filter temperature is estimated by the signal of the temperature detecting means provided outside the heating space in which the influence of microwaves is excluded, and the microwave amount in the heating space It is possible to correct the detection signal based on the filter temperature information, and the reliability of the detection accuracy of the particulate collection amount accumulated on the filter is guaranteed.

(2) Since the microwave detecting means is provided in the exhaust gas non-flowing space of the heating space, the detecting portion is protected from exhaust gas contamination and the detection performance is guaranteed.

(3) Since the temperature detecting means is constructed so as to be able to detect the filter temperature independently of the operating state of the internal combustion engine, the filter regeneration timing can be executed independently of the operation of the internal combustion engine at free timing. .

(4) In the filter regeneration control, the control of the preheating period stored in advance is executed based on the filter temperature in the initial stage of heating and the microwave detection signal, whereby the filter regeneration time can be freely selected. .

(5) The completion of filter regeneration is judged based on the temporal change amount of the temperature detection signal or the microwave detection signal, so that the regeneration failure can be eliminated and the regeneration can be stopped suddenly during the regeneration. It is possible to provide a highly reliable playback device that can be used.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a filter regeneration device for an internal combustion engine according to an embodiment of the present invention.

[Fig. 2] Enlarged view of the main part

FIG. 3 is a main flowchart of a control unit in the internal combustion engine filter regenerating apparatus according to one embodiment of the present invention.

FIG. 4 is a timing chart of control contents and a change characteristic diagram of a detection signal in the internal combustion engine filter regenerating apparatus according to an embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional filter regeneration device for an internal combustion engine.

[Explanation of symbols]

 14 Internal Combustion Engine 15 Heating Space 16 Filter 17 Microwave Generation Means 27 Drive Power Supply Section 32 Air Supply Means 36 Microwave Detection Means 37 Temperature Detection Means 38 Control Section 39 Storage Section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahiro Matsumoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yasuyuki Motozuka, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (7)

[Claims] 1. A microwave generation means, a drive power source section for operating the microwave generation means, a heating space for supplying microwaves generated by the microwave generation means, and an internal combustion engine provided in the heating space. A filter for collecting particulates contained in the exhaust gas to be discharged, an air supply means for supplying air to flow through the filter, a microwave detection means for detecting a microwave amount in the heating space, and A filter regeneration device for an internal combustion engine, comprising: a temperature detection means provided outside the heating space to detect the temperature of exhaust gas or air flowing through the filter. 2. The filter regenerating apparatus for an internal combustion engine according to claim 1, wherein the microwave detecting means detects the amount of microwaves in the exhaust gas non-flowing space in the heating space. 3. The temperature detecting means detects the temperature of the exhaust gas discharged by the internal combustion engine while the internal combustion engine is operating, and activates the air supply means while the internal combustion engine is stopped to operate the air temperature after passing through the filter. The filter regeneration device for an internal combustion engine according to claim 1, wherein the filter regeneration device is configured to detect 4. A control unit for inputting a temperature detection signal and a microwave detection signal is provided, and the operations of a drive power supply unit and an air supply unit for operating the microwave generation unit are controlled based on a command from the control unit. 1. The filter regeneration device for an internal combustion engine according to 1. 5. The command of the control unit is composed of a command for extracting and determining a predetermined control content stored in a storage unit based on an input signal and a command for determining based on a temporal change amount of the input signal. The filter regeneration device for an internal combustion engine according to claim 4. 6. A filter regeneration for an internal combustion engine according to claim 5, wherein a preheating period of the particulates by the microwave is defined by a predetermined time stored in a storage section which is determined based on the temperature detection signal and the microwave detection signal. apparatus. 7. A filter regenerating apparatus for an internal combustion engine according to claim 5, wherein combustion completion of particulates is defined based on a temporal change amount of the temperature detection signal or the microwave detection signal.