JP2003172126A - Exhaust emission control device provided with reflecting plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce power consumption when reproducing a filter by providing a reflecting plate outside the filter, in the exhaust emission control device. <P>SOLUTION: A cylindrical reflecting plate 50 extending along the longitudinal direction of the filter 2 is supported by a supporting member 47 in an exhaust passage 33 formed on an outer periphery of the filter 2 within a housing 1. The reflecting plate 50 reflects heat generated upon reproduction by heating and burning particulate matter scavenged in the filter 2 by energizing a heater provided on the filter 2 to prevent heat radiation to the housing 1, maintains a combustion temperature of the filter 2 to a high temperature and reduces power consumption by the heater. The reflecting plate 50 is supported on the housing 1 by a spring member 45 to allow a thermal expansion difference between itself and the filter 2 when heating and burning particulate matter and the reflecting plate 50. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention collects particulate matter contained in exhaust gas discharged from an engine with a filter and energizes a heater provided in the filter to incinerate the particulate matter. The present invention relates to an exhaust gas purification device that regenerates a filter.

[0002]

2. Description of the Related Art Conventionally, as a diesel particulate filter, that is, as an exhaust gas purifying apparatus, carbon of suspended particles is contained in exhaust gas discharged from a diesel engine.
A filter having a structure in which ceramic fibers are laminated or a filter having a honeycomb structure made of porous ceramics is used to remove particulate matter such as soot, HC, and SO _X. When the filter collects the particulate matter, particles of the particulate matter are caught on the filter made of the ceramic fiber material, and these particles gradually increase in size, and are deposited while filling the gap between the adjacent fiber materials. Further, the filter that has collected the particulate matter needs to be burned and regenerated by heating the particulate matter. At that time, the heater provided in the filter must be energized to heat and burn the particulate matter to regenerate the filter. I have to. Regeneration of the filter requires a large amount of electric power, and in order to obtain the large amount of electric power, the engine is provided with, for example, a permanent magnet generator.

The diesel particulate exhaust treatment device disclosed in Japanese Utility Model Laid-Open No. 61-149715 discloses a filter member disposed in an exhaust gas passage for collecting particulates in exhaust gas. And a heater member for igniting and burning particulates disposed in the vicinity of the end of the filter member in the exhaust gas inflow direction, and further provided in the filter member so as to penetrate therethrough in the exhaust gas flowing direction. And a flow rate control mechanism for increasing the flow rate of the exhaust gas flowing into the cavity when the collected particulates are ignited and burned.

Further, the diesel particulate filter device having a self-regenerating function disclosed in Japanese Unexamined Patent Publication (Kokai) No. 8-313329 is capable of lowering the ignition temperature of particulates and reducing the supply of electric power to the energized wire mesh. A filter is arranged in each of a pair of exhaust gas passages provided in the exhaust system, and a conductive wire mesh and an oxidation catalyst wire mesh that lowers the oxidation reaction temperature are arranged in each filter. The diesel particulate filter device operates a shutter valve provided in an exhaust gas passage so as to automatically throttle the exhaust gas flow rate in response to exhaust pressure of a predetermined value or more, and the particulate metal is ignited by an oxidation catalyst wire mesh. The temperature drops,
When the shutter valve is closed, the particulate easily ignites and burns.

As a filter constituting a diesel particulate filter, a filter using a ceramic non-woven fabric is known (see, for example, Japanese Patent No. 3164966). Diesel particulate filter is made of ceramics non-woven fabric as a filter for trapping particulate matter contained in exhaust gas to improve the collection efficiency, reduce fiber scattering of ceramics non-woven fabric, durability and corrosion resistance. The ceramic filter is formed into a cylindrical shape by sequentially folding it in a circumferential direction between the inner side and the outer side with a ceramic non-woven fabric, and the basis weight of the ceramic non-woven fabric is 200 to 350 g / m ² . The fiber length of the ceramics non-woven fabric is adjusted to 35 mm or more by setting the range, and the wire mesh heater is arranged on the exhaust gas inflow side to the felt made of the ceramic non-woven fabric in order to heat and incinerate the particulate matter collected by the filter. The entire exhaust gas inflow side is surrounded by a wire mesh heater.

[0006]

However, the above diesel particulate exhaust treatment device ignites and burns the particulates such as carbon and smoke captured by the heater disposed in the vicinity of the filter, The filter is playing. Therefore, the exhaust gas purifier uses the propagation of flame to regenerate the area other than the tip of the filter, and due to the non-uniform soot adhesion to the filter, poor regeneration due to unburned soot and melting of the filter due to abnormal combustion. The problem is that loss and damage to the filter due to thermal stress. A conventional diesel particulate filter is provided with two filters. One filter collects particulate matter contained in exhaust gas and the other filter collects particulate matter in a heater. Power is supplied to regenerate the filter. Therefore, in the diesel particulate filter, the effective utilization ratio of the filter that traps the particulate matter in the exhaust gas is as low as 50% in the system in which one filter is regenerated. In addition, the power consumption is large because the filter is regenerated, and the current power of the vehicle is insufficient.

Further, the filter used in the conventional diesel particulate filter is made of a ceramic fiber material and is formed into a shape which is bent in a cylindrical shape and has a large surface area, and the particulate matter is heated and burned. When the filter is heated, the ambient temperature of the filter rises, and the temperature rise causes the pleated cylindrical body to be thermally deformed. Therefore, in order to maintain its shape, the folded portion of the pleated filter must be reinforced with heat-resistant ceramics or the like. Not, again,
Since the filter has a cylindrical shape, the arrangement inside the housing becomes complicated, the number of filter parts increases, and the manufacturing cost increases.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and a reflector is provided outside the filter in the housing so that the high temperature at the time of regeneration of the filter is not radiated to the outside. In addition, by maintaining the high temperature without reducing the combustion temperature in the filter at the time of regeneration, the particulate matter is satisfactorily heated and incinerated, the power consumption is reduced, and at least three housings are arranged in the housing. , At least two filters collect the particulate matter contained in the exhaust gas, increase the effective collection efficiency of the filter, and heat and incinerate the particulate matter collected in the filter by energizing the heater, The power consumption supplied to the heater is reduced, heating and incineration of the filter is reliably achieved in a short time, and the filter is regenerated in sequence, Structure can be simplified and the control is to provide an exhaust gas purifying device is easy.

According to the present invention, a housing connected to an exhaust pipe for discharging exhaust gas from an engine, and a particulate matter contained in the exhaust gas disposed in the housing are collected and collected. In an exhaust gas purifying apparatus having a filter for heating and incinerating particulate matter, a cylindrical reflecting plate extending along the longitudinal direction of the filter is supported in an exhaust gas passage formed in the housing on the outer periphery of the filter. The reflecting plate is arranged by a member, and the heater provided in the filter is energized to reflect the heat generated at the time of regeneration in which the particulate matter trapped in the filter is incinerated to the housing. The present invention relates to an exhaust gas purifying device, characterized in that the heat dissipation of the exhaust gas is prevented and the regeneration temperature of the filter is maintained.

The reflecting plate is supported on the housing by a spring member and / or a link mechanism in order to allow a difference in thermal expansion between the reflecting plate and the filter due to heat generated in the filter due to heating and burning of the particulate matter. Has been done.

The filter is formed of a ceramic non-woven fabric, a wire mesh and a heater in a corrugated shape in the circumferential direction and is formed into a tubular body as a whole, and has a frame reinforcing member for reinforcing and holding the corrugated shape of the tubular body. In addition, one end of the reflection plate is supported by a support member that supports the frame reinforcing member for allowing the thermal expansion difference of the filter.

In this exhaust gas purifying apparatus, the housing is divided into at least three or more compartments by partition walls, and the filters are arranged in the compartments so as to form exhaust gas passages on the inner and outer circumferences thereof, respectively. An opening / closing valve for opening / closing an exhaust gas inlet of the chamber is arranged, and the opening / closing valve is controlled to be opened to send the exhaust gas from the exhaust pipe to the compartment, and the particulates collected by the filter are also provided. In order to regenerate the filter by heating and incinerating the substance, the on-off valve is closed, and the heater provided in the filter is energized.

Further, in this exhaust gas purifying apparatus, an inlet pipe is connected to the housing, the inlet pipe communicating with the exhaust pipe to form a gas chamber for sending the exhaust gas to the partition chamber, and the partition of the housing. A collecting pipe for collecting the exhaust gas discharged from the compartment is connected to the chamber.

At least three compartments are formed in the housing, and the controller opens the valves of at least two compartments to remove the particulate matter contained in the exhaust gas. In addition to the collection process of collecting in the filter, the regeneration process of closing the on-off valve of at least one of the compartments and energizing the heater to heat and incinerate the particulate matter collected in the filter, Control sequentially over time.

The compartment formed in the housing is provided with air supply means for supplying combustion air of the particulate matter when the filter is regenerated.

In the exhaust gas purifying apparatus, when the filter is regenerated by heating and burning the particulate matter, combustion air flows through the exhaust gas passage on the inner and outer peripheries of the reflection plate, and the particulate matter is filtered by the filter. When collecting a substance, the exhaust gas flows through the exhaust gas passage on the inner and outer circumferences of the reflector.

The air supply means is formed in the air passage, which is formed around the inlet of the compartment and has a plurality of air outlets for radially ejecting the combustion air to the compartment. An air pump for feeding the combustion air to the air passage through the air inlet, and an air distribution valve for controlling the feed of the combustion air to the air inlet.

The filter is a ceramic non-woven fabric having excellent heat resistance, a pair of metal nets for sandwiching and holding the ceramic non-woven fabric from the upstream and downstream directions of the exhaust gas flow,
And a heater embedded in the ceramic nonwoven fabric to form a five-layer structure.

This exhaust gas purifying device is, as described above,
Since the reflector is installed on the outside of the filter, the combustion heat of the particulate matter is not radiated to the outside when the filter is regenerated, but is reflected and the filter temperature can be maintained at a high temperature, resulting in smooth heating and burning of the particulate matter. The power consumption can be reduced and the heat radiation to the housing can be prevented. Further, when collecting the particulate matter in the exhaust gas of the filter, the exhaust gas flows through the inner and outer peripheries of the reflection plate, there is no temperature difference between the inner and outer peripheries, and the reflection plate does not fulfill the function of reflecting heat. Further, since the reflector is supported by the bracket of the spring member in the housing, even if a difference in thermal expansion occurs between the reflector and the filter, the difference in thermal expansion is tolerated and the reflector is always well supported by the housing. Will be done.

Further, in this exhaust gas purifying apparatus, the filters are arranged in three or more compartments divided by the partition wall in the housing, and the on-off valves are arranged in the compartments. The filter can be regenerated and at least three filters with different clogged states by the particulate matter can be alternately regenerated so that two or more filters collect the particulate matter from the exhaust gas. The effective collection efficiency of the filter that collects the particulate matter from the exhaust gas is increased, and one filter is regenerated, and the power consumption required to energize the heater is reduced to two. It can be reduced as compared with the case of alternately reproducing at. Further, since this exhaust gas purifying device performs the collection operation of the particulate matter by two out of three, the change in the pressure loss during the exhaust gas collection elapsed time is lower than that in the case of performing by one. , For example, can be reduced to 2/3 or less,
Even when the EGR process is performed to reduce the generation of NO _X , the fluctuation of the exhaust gas pressure can be significantly reduced, and thus the smooth EGR can be performed, and therefore, the particulate matter can be efficiently collected and It is possible to reduce the generation of NO _X due to EGR.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an exhaust gas purifying device according to the present invention will be described below with reference to the drawings. This exhaust gas purifying apparatus has a filter 2 in which a particulate matter composed of carbon, soot, HC, SO _X, etc. contained in exhaust gas discharged from an engine is arranged in a housing 1.
The particulate matter trapped by the filter 2 is energized by heating the heater 6 provided in the filter 2 to incinerate it by heating, and the filter 2 is regenerated. is there.

In this exhaust gas purifying apparatus, the housing 1 is connected to an inlet side exhaust pipe 11 through which exhaust gas from an engine flows and an outlet side exhaust pipe 12 through which purified exhaust gas is discharged, and the inlet side exhaust pipe 11 is connected. Is installed by being connected to an exhaust pipe (not shown) through which exhaust gas generated by the engine is discharged. This exhaust gas purification device can be easily attached to the vehicle body or frame with a bracket or the like. For example, since it has a sound deadening function, it can be easily attached to the place where the muffler is installed instead of the muffler provided in the existing vehicle. You can also Further, it is needless to say that this exhaust gas purifying device can be easily constructed so that the outer surface of the housing 1 is a heat shield structure with a heat shield member or the like so that the vehicle is not damaged by heat.

As shown in FIG. 7, at least three housings 1 are formed by partition walls 4 (3 in FIGS. 2, 3 and 7).
The compartments 3 are divided into compartments 3 and the filters 2 are arranged in the compartments 3 so as to form the exhaust gas passages 33 on the outside thereof. The filter 2 has one end held by the filter holding pipe 71 in the housing 1, and the other end supported by the support member 47 in the housing 1 by screws 49 or the like. On the upstream side of the housing 1, an inlet pipe 7 is connected which communicates with the inlet side exhaust pipe 11 and forms a gas chamber 17 for sending the exhaust gas from the inlet side exhaust pipe 11 to the compartment 3. A collecting pipe 8 that communicates with the exhaust pipe 12 on the outlet side and collects the exhaust gas sent from the dividing chamber 3 is connected to the dividing chamber 3. Further, on-off valves 5 for opening and closing the exhaust gas inlet 13 of the compartment 3 are arranged.

This exhaust gas purifying device is particularly shown in FIG.
As shown in FIG. 13, a cylindrical reflector plate 5 is provided in the exhaust gas passage 33 outside the filter 2 so as to be spaced from the outer peripheral surface of the filter 2.
0 is supported by the housing 1 by the support member 72. This exhaust gas purifying device has a housing 1
In the exhaust gas passage 33 formed inside the outer periphery of the filter 2, a cylindrical reflecting plate 50 extending along the longitudinal direction of the filter 2 is arranged by a supporting member 72. Reflector 5
0 occurs at the time of regeneration in which the valve body 20 of the on-off valve 5 closes the exhaust gas inlet 13 and energizes the heater 6 provided in the filter 2 to heat and incinerate the particulate matter trapped in the filter 2. The heat is prevented from being reflected and transferred to the housing 1, and the combustion temperature of the particulate matter at the time of regeneration of the filter 2 is secured to reduce the power supplied to the heater 6 to reduce the power consumption. On-off valve 5
When the valve body 20 opens the exhaust gas inlet 13 and collects the particulate matter in the exhaust gas by the filter 2, the exhaust gas passes through the exhaust gas passage 33, and thus passes through the inner and outer peripheries of the reflection plate 50. However, the reflection plate 50 is in a state where it does not exhibit the heat reflection function.

The cylindrical reflection plate 50 is supported by the housing 1 by a spring member 45 or a link mechanism in order to allow a difference in thermal expansion of the reflection plate 50 due to the heat generated in the filter 2 by the heating and burning of the particulate matter. There is. As shown in FIG. 12 and FIG. 13, the reflector 50 includes a filter 2
At the inlet side of the filter, an end plate provided to reinforce the filter 2, that is, a reinforcing member 3 for a frame that reinforces the filter 2.
5 to the support member 47 for supporting the disk member 40 of the spring member 4
5 and is attached to the housing 1 by a spring member 45 on the outlet side of the filter 2. Generally, the engine exhaust gas temperature is 150 ° C.
It is about 650 ° C. When playing filter 2,
When energizing the heater 6 to heat and incinerate the collected particulate matter, the temperature of the filter 2 is 600 ° C to 8 ° C.
Raise to 00 ° C. At this time, the temperature of the housing 1 becomes 150 ° C. to 200 ° C. due to the heat reflecting action of the reflection plate 50.
Further, the reflection plate 50 needs to satisfy the temperature conditions as described above, but when incorporated in the filter 2, the reflection plate 50 thermally expands in the longitudinal direction. The reflecting plate 50 is made of a metal material having a small thermal expansion in order to minimize the thermal expansion in the longitudinal direction, and the reflecting plate 50 is made of a spring member 45 or a spring member 45 in order to allow the thermal expansion difference. A structure in which the housing 1 is supported by a link mechanism is adopted.

Further, since the controller 10 sends the exhaust gas from the inlet side exhaust pipe 11 to the compartment 3, the controller 10 controls the opening / closing valve 5 to open and heats and incinerates the particulate matter collected by the filter 2. In order to regenerate the filter 2, the on-off valve 5 is closed and the heater 6 provided in the filter 2 is energized. The heater 6 is energized by the control of the controller 10 from the power source such as the battery 51 through the energizing electrode 55 provided in the filter 2.

The controller 10 controls the collection process of opening the open / close valves 5 of at least two compartments 3 to collect the particulate matter contained in the exhaust gas in the filter 2 and at least one compartment. The on-off valve 5 of the chamber 3 is closed and the heater 6 is energized to control the regeneration process of heating and incinerating the particulate matter trapped in the filter 2. These controls are performed as shown in FIG. Filter 2
Is set to sequentially control with respect to.
Electric power supplied to the heater 6 is supplied by, for example, a permanent magnet type generator 53 mounted on the vehicle. The controller 10 responds to the amount of particulate matter deposited on the filter 2 and the temperature of the filter 2 in response to the actuator 2
The on-off valve 5 is controlled to be opened and closed by the control unit 4, and the exhaust chamber
Control infeed.

The housing 1 includes, for example, the housing 1
A bypass passage 9 is formed by the partition wall 4 that forms the compartment 3 in the central portion of the. The bypass passage 9 is configured to open against the spring force of the spring 70 or the like when an exhaust gas pressure higher than a predetermined pressure is applied. The bypass passage 9 serves an emergency evacuation function and is opened by the safety valve 14. Therefore, for example, when the system of the controller 10, the sensor, the actuator, etc. fails, the vehicle is urgently sent to a repair place or the like. It can be moved. The housing 1 does not necessarily have to be provided with the bypass passage 9, but it is necessary to consider safety in case of emergency such as a safety valve. Further, when the bypass passage 9 is formed by the partition wall 4 in the central portion of the housing 1, the bypass passage 9 can be formed without increasing the overall size of the housing 1, and the waste space can be effectively utilized, and the device itself. Can be formed compactly.

In the compartment 3 formed in the housing 1,
Air supply means 15 is provided for supplying combustion air of the particulate matter when the filter 2 is regenerated.
The air supply means 15 is formed around the inlet 13 of the compartment 3 and is provided in the air passage 16 with a plurality of air outlets 68 that blow out combustion air radially to the compartment 3, and the air formed in the air passage 16 It has an air pump 18 for sending combustion air to the air passage 16 through the inlet 69, and an air distribution valve 19 for controlling the supply of combustion air to the air inlet 69. The air distribution valve 19 may be a triple solenoid valve or the like, and is configured to supply air to one compartment 3. When the filter 2 is regenerated, the combustion air is opened by the operation of the air pump 18 by the air distribution valve 19 to open the air inlet 69 that communicates with the compartment 3 at the time of regeneration, and through the air inlet 69, the air passage 16 of the predetermined compartment 3 is opened. To the exhaust gas passage 33 in the compartment 3 from the air outlet 68 provided in the air passage 16.

The housing 1 has a substantially cylindrical outer shape, and the filters 2 arranged in the compartments 3 respectively.
Is formed in a tubular shape. The exhaust gas flowing from the gas chamber 17 into the compartment 3 flows from the outer side to the inner side of the filter 2 and is exhausted to the outlet side exhaust pipe 12 through the collecting pipe 8. The on-off valve 5 is composed of a valve body 20 that opens and closes the exhaust gas inlet 13 of the compartment 3, and a drive motor 22 that opens and closes the valve body 20 by a link mechanism 21 and an actuator 24 that includes a speed reducer 23. ing. Since it is necessary to overcome the exhaust gas pressure to open and close the on-off valve 5, the actuator 24 increases the torque of the drive motor 22 through the speed reducer 23, and thereby the link mechanism 21.
Is operated to open the exhaust gas inlet 13 of the valve body 20.

The exhaust pipe 11 on the inlet side is provided with a temperature sensor 25 such as a thermocouple for detecting the temperature of the exhaust gas fed into the compartment 3 of the housing 1, and a pressure sensor 26 for detecting the pressure. ing. The temperature sensor 25 measures the temperature of the exhaust gas, and the controller 10 determines the filter 2 from the result of the exhaust gas temperature, the detected value of the pressure sensor 26 and the engine rotation speed measured by the rotation sensor 72 of the generator or the engine. It is possible to calculate the clogging rate of the particulate matter collected in the above, that is, the collection amount, and command the regeneration timing of the filter 2. Others, for example,
In order to measure the temperature of the filter 2, the temperature sensor 74 can be arranged along the high temperature region of the bent portion of the bellows of the filter 2, which is the highest temperature region of the filter 2. The temperature in the entire area of the filter 2 is substantially adjusted to a temperature equal to or lower than the temperature detected by the temperature sensor 74, and the amount of electricity supplied to the heater 6 during regeneration of the filter 2 and the amount of air supply of the air pump 18 are controlled to control the filter 2 Is prevented from being damaged by local overheating or the like. The controller 10 controls opening / closing of the opening / closing valve 5 in response to detection signals from the temperature sensors 25, 74, the rotation sensor 73, the pressure sensor 26, etc., controls the energization of the heater 6, and further supplies it to the compartment 3. The air supply means 15 is controlled to supply the combustion air. Also,
The controller 10 includes information on the temperature sensors 25 and 74, the rotation sensor 73, the pressure sensor 26, the battery 51, the power supply control device 52, the permanent magnet generator 53, etc., or the filter 2
Is playing, and trouble information indicator 54
Is configured to display. The generator 53 can be the one mounted on the vehicle, but another generator can be additionally mounted.

The filter 2 comprises an upstream ceramic non-woven fabric 27 and a downstream ceramic non-woven fabric 28 having excellent heat resistance,
The ceramic non-woven fabrics 27 and 28 are arranged between the upstream and downstream metal nets 29 and 30, and the upstream ceramic non-woven fabric 27 and the downstream ceramic non-woven fabric 28, which sandwich and hold the ceramic non-woven fabrics 27 from the upstream and downstream directions of the exhaust gas. , A heater 6 such as a wire mesh heater embedded in the ceramic non-woven fabric 27, 28 is formed into a five-layer structure. The ceramics non-woven fabrics 27 and 28 improve durability by being sandwiched between a shape-retaining wire net 29 and a wire net 30, and by forming a five-layer structure, a unit of particulate matter such as soot and carbon. The collection efficiency per area can be increased. Further, by interposing the heater 6 such as a wire mesh heater between the ceramic non-woven fabrics 27 and 28, in other words, by embedding it, it is possible to effectively utilize the electric power.

The ceramics non-woven fabrics 27 and 28 are composed of at least silicon carbide non-woven fabrics, and the fiber density of the upstream part of the exhaust gas flow, that is, the upstream ceramics non-woven fabric 27 is coarse, and the downstream part, that is, the downstream ceramics non-woven fabric 2
The fiber density of 8 is densely formed. The ceramic nonwoven fabrics 27 and 28 are heat resistant ceramics such as silicon carbide (SiC), silicon nitride (Si ₃ N ₄ ), and alumina (Al ₂ O ₃ ).

The filter 2 is disposed in the housing 1 so as to extend in the longitudinal direction from one side of the housing 1 to the other side facing the exhaust gas in a direction intersecting with the flow of exhaust gas. In addition, the filter 2 is bent as a whole in the circumferential direction in a bellows shape or a corrugated shape to form an exhaust gas passage 34 inside in order to increase a surface area in contact with exhaust gas, that is, a collecting area. 31 is compactly formed. In FIG. 9, the end of the filter 2 is shown in an open state, but specifically, the inlet side of the compartment 3 is closed by the end plate 75, and the outlet side of the compartment 3 holds the filter. An annular ring 76 with an outlet 77 communicating with the pipe 71 closes the filter end face. As a result, the exhaust gas flows from the outer peripheral side to the inner peripheral side of the cylindrical body 31, and the particulate matter contained in the exhaust gas is collected by the filter 2. Since the exhaust gas is configured to flow from the exhaust gas passage 33 on the outer peripheral side of the filter 2 to the exhaust gas passage 34 on the inner peripheral side, radial expansion due to exhaust gas heat of the filter 2 is prevented.
Further, the tubular body 31 forming the filter 2 has a plurality of shape fixing rings 32 arranged on the inner and outer circumferences thereof at a plurality of positions in the longitudinal direction.

This exhaust gas purifying device is constructed as described above, and the exhaust gas is sent from the inlet side exhaust pipe 11 through the inlet pipe 7 to two of the three compartments 3,
The particulate matter contained in the exhaust gas is trapped by the filter 2 when being sent to the filter 2 arranged in the compartment 3 and passing through the filter 2. One of the three compartments 3 is closed by the on-off valve 5, the heater 6 is energized, and the particulate matter collected in the filter 2 is heated and incinerated to purify the exhaust gas. 8 is discharged to the outlet side exhaust pipe 12. Therefore,
As shown in FIG. 11, this exhaust gas purifying apparatus reduces the pressure loss YmmHg in the elapsed time to 2/3 or less as compared with the pressure loss XmmHg in the elapsed time due to the alternating operation of two conventional filters. can do.

In order to prevent overheating of the filter 2, the controller 10 controls the energization of the heater 6 in response to the temperature detected by the filter 2 from the temperature sensor 74, and the drive motor 22 for driving the air pump 18. The operation is controlled to adjust the supply amount of exhaust gas and air into the exhaust gas passage 33. The controller 10 regenerates the filter 2, for example, when the temperature sensor 74 indicates a high temperature,
The rotation speed of the motor 22 is reduced to send a small amount of air to the filter 2 to reduce the combustion speed of the particulate matter trapped in the filter 2 and suppress the temperature rise of the filter 2.

The controller 10 detects the pressure value detected by the pressure sensor 26, or detects the pressure value or the pressure difference determined in advance by the pressure difference due to the pressure value of the upstream and downstream passages of the filter 2 by the pressure sensor. If it becomes larger, it is recognized that the particulate matter trapped in the filter 2 has reached a predetermined trapping amount, the regeneration is started in response to the pressure value or the pressure difference, and then the filter 2 In order to heat and incinerate the deposited particulate matter, the heater 6 is energized. Further, the controller 10 controls the operation of the air pump 18 and the operation of the actuator 24 that opens and closes the open / close valve 5 in response to the regeneration of the filter 2. Further, the controller 10 controls the operating state of the air pump 18 in response to the operating state of the engine such as the engine speed detected by the rotation sensor and the engine load detected by the load sensor.

[0038]

Since the exhaust gas purifying apparatus according to the present invention is constructed as described above, the reflecting plate can maintain the filter temperature at a high temperature when the filter is regenerated, the electric power supplied to the heater can be reduced, and the power consumption can be reduced. Can be reduced. In addition, in this exhaust gas purification device, the housing in which the filter is installed can be constructed in an extremely compact structure, not to mention new cars,
It can be easily attached to existing vehicles as a muffler mounting structure or as a muffler with a muffling function. In this exhaust gas purification device, filters are arranged in at least three compartments, respectively, and the particulate matter in the exhaust gas is collected by at least two filters, so the collection effective utilization rate of the filters is increased, Further, since the filter is regenerated by one filter, the electric power used is low, the filter can be regenerated, and it is extremely preferable to be mounted on a vehicle or the like where the electric power is easily insufficient.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an embodiment of an exhaust gas purifying device according to the present invention.

FIG. 2 is a side view showing a front end of the exhaust gas purification device of FIG.

FIG. 3 is a side view showing a rear end of the exhaust gas purification device of FIG.

FIG. 4 is a schematic sectional view showing an embodiment of an exhaust gas purification device according to the present invention.

FIG. 5 is a perspective view showing an inlet pipe attached to a housing in the exhaust gas purification device.

FIG. 6 is a perspective view showing a collecting pipe attached to a housing in the exhaust gas purification device.

FIG. 7 is a perspective view showing an arrangement state in which filters are respectively arranged in compartments of a housing in this exhaust gas purification device.

FIG. 8 is an explanatory diagram showing a filter having a five-layer structure in this exhaust gas purification device.

FIG. 9 is a perspective view showing a filter in this exhaust gas purification device.

FIG. 10 is a diagram illustrating a regeneration cycle of three filters in this exhaust gas purification device.

FIG. 11 is a diagram showing pressure loss with respect to elapsed time for a filter.

FIG. 12 is a schematic cross-sectional view showing a structure in which a reflection plate is provided outside the filter.

13 is a side view showing an end face of FIG. 12. FIG.

[Explanation of symbols]

1 housing 2 filters 3 compartments 4 partitions 5 on-off valve 6 heater 7 Inlet pipe 8 collecting pipe 10 controller 11 Inlet side exhaust pipe 12 Outlet side exhaust pipe Exhaust gas inlet of 13 compartments 15 Air supply means 16 air passages 17 gas chamber 18 air pump 19 Air distribution valve 27 Ceramics non-woven fabric (upstream side) 28 Ceramics non-woven fabric (downstream side) 29 Wire mesh (upstream side) 30 wire mesh (downstream side) 31 cylinder 33 Exhaust gas passage on outer peripheral side of filter 34 Exhaust gas passage on inner side of filter 35 Reinforcing member for frame 45 Spring member 47,72 Support member 50 reflector 68 Air outlet 69 air inlet

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F01N 3/02 F01N 3/02 341L 341N 341P 341R // B01D 46/42 B01D 46/42 B F term (reference) ) 3G090 AA02 BA04 CB15 CB18 CB23 CB24 DA03 DA12 DA13 DA18 EA01 4D058 JA10 JB03 JB06 JB24 JB25 KB01 MA42 SA08 UA30

Claims (10)

[Claims] 1. A housing connected to an exhaust pipe for discharging exhaust gas from an engine, and a particulate matter contained in the exhaust gas, which is disposed in the housing, and the particulate matter collected. In an exhaust gas purifying apparatus having a filter for heating and incinerating a substance, a cylindrical reflecting plate extending along a longitudinal direction of the filter is supported by a supporting member in an exhaust gas passage formed in an outer periphery of the filter in the housing. The reflection plate reflects the heat generated during regeneration in which the heater provided in the filter is energized to heat and incinerate the particulate matter collected in the filter, and the heat is radiated to the housing. And an exhaust gas purification device that maintains the regeneration temperature of the filter. 2. The reflection plate allows a difference in thermal expansion between the reflection plate and the filter due to heat generated in the filter by heating and incineration of the particulate matter,
The exhaust gas purifying apparatus according to claim 1, wherein the exhaust gas purifying apparatus is supported by the housing by a spring member and / or a link mechanism. 3. The filter is a ceramic non-woven fabric,
It has a frame reinforcing member which is bent into a corrugated shape in the circumferential direction from the wire netting and the heater and is formed into a cylindrical body as a whole, and which reinforces and holds the corrugated shape of the cylindrical body.
The exhaust gas purifying apparatus according to claim 1 or 2, wherein one end of the reflection plate is supported by a supporting member that supports the frame reinforcing member for allowing the thermal expansion difference of the filter. . 4. The housing is divided into at least three or more compartments by a partition wall, and the filters are arranged in the compartments so as to form exhaust gas passages on the inner and outer circumferences thereof, respectively. Opening / closing valves for opening and closing the exhaust gas from the exhaust pipe are sent to the compartment, and the opening / closing valve is controlled to open and the particulate matter collected in the filter is incinerated by heating. The exhaust gas purification according to any one of claims 1 to 3, further comprising a controller for controlling the closing of the on-off valve to regenerate the filter and controlling the energization of the heater provided in the filter. apparatus. 5. An inlet pipe, which communicates with the exhaust pipe and forms a gas chamber for sending the exhaust gas to the compartment, is connected to the housing, and the compartment of the housing is connected to the compartment from the compartment. 5. A collecting pipe for collecting the exhaust gas to be sent out is connected.
Exhaust gas purifier according to. 6. The housing is formed with at least three compartments, and the controller opens the valves of at least two compartments to contain the particulate matter contained in the exhaust gas. Together with a collection process for collecting the particulate matter in the filter, and a regeneration process for closing the on-off valve of at least one of the compartments and energizing the heater to heat and incinerate the particulate matter collected in the filter. The exhaust gas purifying apparatus according to claim 4 or 5, wherein the exhaust gas is controlled sequentially over time. 7. The air supply means for supplying combustion air of the particulate matter to the compartment formed in the housing when the filter is regenerated. The exhaust gas purification device according to any one of 1 to 6. 8. When regenerating the filter by heating and burning the particulate matter, combustion air flows through the exhaust gas passage on the inner and outer circumferences of the reflection plate, and the particulate matter is collected by the filter. The exhaust gas purifying apparatus according to any one of claims 4 to 7, wherein the exhaust gas sometimes flows through the exhaust gas passages on the inner and outer circumferences of the tubular reflecting plate. 9. The air passage, wherein the air supply means has a plurality of air outlets formed around the inlet of the compartment and radially ejecting the combustion air to the compartment.
An air pump for feeding the combustion air to the air passage through an air inlet formed in the air passage, and an air distribution valve for controlling the feed of the combustion air to the air inlet. 8. The exhaust gas purification device according to item 8. 10. The filter comprises a ceramic non-woven fabric having excellent heat resistance, a pair of wire nets for holding the ceramic non-woven fabric by sandwiching the ceramic non-woven fabric from the upstream and downstream directions of the exhaust gas flow, and the heater embedded in the ceramic non-woven fabric. The exhaust gas purifying device according to any one of claims 4 to 9, wherein the exhaust gas purifying device is formed of a five-layer structure.