JP2001248423A - Diesel particulate filtering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diesel particulate filtering device capable of properly collecting the particulate substances by a filter or heating and burning them by accurately detecting how the particulate substances are collected by a pressure ratio of exhaust gas at the upstream and downstream of the filter. SOLUTION: Particulate substances in exhaust gas are collected by making a pair of filters 1F, 2F alternately function, and the particulate substances collected in one filter are heated and burnt. How the particulate substances are collected in the filter IF, 2F is detected by a pressure ratio detected by pressure sensors 15, 16 provided on exhaust pipes 10, 11 at the upstream and downstream of the filter 1F, 2F. A throttle valve 22 is provided on the exhaust pipe 11 to properly keep the exhaust pressure of the exhaust pipe 11, and a throttle valve 23 is provided on an exhaust pipe 5 to uniform the exhaust pressures of the exhaust pipe 5 on the straight outlet side and the exhaust pipe 4 on the bent outlet side.

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 for collecting particulates contained in exhaust gas discharged from a diesel engine with a filter and regenerating the filter by heating and burning the collected particulates. Related to the device.

[0002]

2. Description of the Related Art Conventionally, suspended matter, carbon, smoke, HC, SO contained in exhaust gas exhausted from an engine is known.
_As a particulate filter for removing particulates such as _X, a filter having a structure in which ceramic fibers are laminated and a filter having a honeycomb structure made of porous ceramics are known. This type of filter generally regenerates the filter by heating and burning the particulate using a heat source when the particulate is collected and the filter is clogged.

[0003] In addition, the regeneration device for a diesel particulate filter disclosed in Japanese Patent Application Laid-Open No. H11-125109, as shown in FIG. 7, branches off from an exhaust pipe 70 communicating with an exhaust manifold of a diesel engine. A pair of branch pipes 71 and 72, each branch pipe 7
Filters 73 and 74 that are attached to the exhaust pipes and collect particulates contained in the exhaust gas, a switching valve 76 that operates to flow the exhaust gas to one or both of the branch pipes 71 and 72, a switching valve 76, and a filter. A communication pipe 77 is provided in the communication pipe 77 for communicating the two branch pipes 71, 72 between the pipes 73, 74, and a communication pipe 77 including an on-off valve 82 opened only at the time of regeneration and a flow control valve 81 for controlling the flow rate of exhaust gas. And a regeneration control valve 83. When the switching valve 76 is switched to introduce the exhaust gas into one branch pipe 71 and block the flow of the exhaust gas into the other branch pipe 72, the particulates contained in the exhaust gas are provided in the one branch pipe 71. Collected by the filter 73.

When the pressure loss of the filter 73 exceeds a predetermined value, the controller 75 sends a signal to the actuator 80 to switch the switching valve 76. The heater provided in the filter 73 is an electrode terminal 84.
It is energized through. When the energization time of the heater reaches a predetermined time and the temperature of the heater reaches a temperature at which the particulates can be burned, the on-off valve 82 opens to open the passage of the communication pipe 77 and the communication pipe 77 is connected to the other branch pipe 72. The exhaust gas is led to the filter 73 through 77. Since the exhaust gas contains oxygen, when the exhaust gas is introduced into the filter 73,
The particulate collected in the filter 73 is incinerated by heating. Also, the filter 74 of the other branch pipe 72 is regenerated in the same manner as the filter 73.

[0005]

However, when the particulates collected by the filter are heated and incinerated in order to regenerate the filter in the diesel particulate filter device, as described above, the exhaust pipe upstream of the filter is used. It is necessary to heat and incinerate the particulates by using the oxygen in the exhaust gas by introducing the exhaust gas into the regenerated filter, or to heat and incinerate the particulate by introducing air from the outside to the regenerated filter. . However, when air is introduced into the regenerated filter from the outside, an air pump for sending air to the filter, an air cleaner for purifying the air because the outside air contains dust and dirt, and removing water from the outside air This requires a water intrusion prevention device or the like for removal, and has a problem that the structure is complicated and the cost is high.

[0006] Further, when the diesel particulate filter device is mounted on a vehicle, space is limited in the vehicle, and good mounting properties are required. When a pair of filters constituting a diesel particulate filter device are arranged in parallel in the longitudinal direction, the size in the width direction increases, and a large space is required in the width direction.
There is a problem with the mountability on vehicles. By the way, an automobile equipped with an engine is provided with a muffler of a silencer in order to reduce noise generated by the flow of exhaust gas. The conventional muffler is configured to extend in the longitudinal direction of the vehicle, and is attached to a lower rear portion of the vehicle. Therefore, if the diesel particulate filter device is provided with a muffling effect to suppress exhaust noise, the diesel particulate filter device can be installed at the place where the muffler is attached instead of the conventional muffler, and the mountability to the vehicle can be improved at once. Will be solved.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems. A pair of filters are arranged so as to extend in series in a longitudinal direction, and the filters extending in the longitudinal direction are connected to the longitudinal direction of a vehicle. The filter can be mounted in any direction, compactly mountable on a vehicle, takes in the exhaust gas from the filter when it is regenerated, and calculates the pressure ratio between the upstream and downstream of the filter. The filter accurately detects the particulate matter trapping state of the filter, properly controls the switching of particulate matter trapping from one side of the filter to the other and regeneration of the filter.
An object of the present invention is to provide a diesel particulate filter device configured to perform control by a timer when a pressure sensor fails.

According to the present invention, there is provided a pair of filter bodies for collecting particulate matter contained in exhaust gas discharged from an engine through an exhaust pipe, and for heating and incinerating the particulates respectively provided in the filter bodies. A pair of filters having a heater, a switching on / off valve for switching to open one of the filters and close the other, an EGR pipe for connecting the exhaust pipe on the outlet side of the filter and the filter, In order to supply a part of the exhaust gas flowing through the exhaust pipe on the outlet side at the time of regeneration of the filter to one of the filters through the EGR pipe, a switching valve provided on the EGR pipe and the EGR pipe are provided. An EGR pump that is operated to supply the exhaust gas through the filter and is provided in the exhaust pipe on the inlet side. Inlet pressure sensor, the outlet side pressure sensor for detecting the exhaust pressure P ₂ of the exhaust gas provided in the exhaust pipe on the outlet side to detect the exhaust pressure P ₁ of the exhaust gas, and the exhaust pressure P _1, P Pressure ratio P ₁ calculated from ₂
The EG with / P ₂ is within the predetermined pressure ratio range in response to being greater than or equal to a predetermined pressure ratio operating between the switching valve and the switching off valve, energizing the heater
A controller for operating an R pump to supply EGR gas to the regeneration-side filter and heating and burning the particulate matter trapped in the filter to regenerate the filter; It relates to a filter device.

The controller supplies electricity to the heater, and in response to the resistance value of the electric system of the heater being within a predetermined resistance value range, removes the particulate matter in the exhaust gas by the filter. Activating a control function for capturing, displaying a failure indicating means of the electric system in response to being outside the resistance value range, and performing control for stopping the control function.

[0010] The controller stores the filter being regenerated in response to the filter being regenerated, and performs control to start regeneration of the filter at the next operation. In addition, the controller stores the filter being regenerated in response to the filter being regenerated, and performs control to start regeneration of the filter at the next operation.

The controller stops the energization of the heater and activates and regenerates the EGR pump in response to the detected temperature from the temperature sensor for detecting the temperature of the filter being equal to or higher than a predetermined temperature. A control for supplying the EGR gas to the filter to be performed is performed.

After the regeneration time of the filter has passed a predetermined time, the controller stops energization of the heater to stop the regeneration operation of the filter,
The control for stopping the R pump and operating the switching valve is performed.

[0013] The controller operates the pressure ratio P ₁ / P
_In response to the value ₂ being out of the pressure ratio range, a failure display means of the pressure sensor is displayed, and the control is switched to control by a timer instead of the pressure sensor. Further, the controller turns on a timer, detects the positions of the switching on / off valve and the switching valve, measures the collection elapsed time by the filter by the timer, and sets the collection elapsed time to a predetermined collection elapsed time. When it reaches, the switching on / off valve and the switching valve are actuated, the flow of the exhaust gas is switched from one of the filters to the other, and the heater is used to heat and incinerate the particulate matter collected by the filter. When the EGR pump is energized and the EGR pump
Control for supplying GR gas to the filter on the regeneration side is performed.

The filter body is formed as a whole by bending a laminated material of ceramic fibers into a pleated shape, and the exhaust gas flows from the outside to the inside of the filter body. The switching valve and the switching valve are provided with a position sensor for detecting a set position, and the controller performs a switching operation between the switching valve and the switching valve according to a detection signal of the position sensor. Control.

The rotation speed of the motor for driving the EGR pump is controlled by the controller according to the operating condition of the engine. Also, the controller is
The rotation speed of the motor according to the detected value of the exhaust gas temperature by the temperature sensor provided upstream of the filter so that the O ₂ amount in the exhaust gas supplied to the filter at the time of regeneration of the filter becomes an appropriate amount. Control.

When the filter is regenerated, the controller increases the rotation speed of the motor when the load on the engine is high, sends a large amount of exhaust gas to the filter, and decreases the rotation speed of the motor when the load is low. A small amount of the exhaust gas is controlled to be sent to the filter.

The filters are arranged in a pair of filter housings longitudinally arranged on both sides of a distribution housing forming a distribution chamber to which the exhaust pipe is connected, and filter inlets of the filter housing face each other. Opening to the distribution chamber, the filter outlet of the filter housing is located opposite the filter inlet.

One of the filter outlets of the filter housing is connected to a straight outlet-side exhaust pipe and the other is connected to a curved outlet-side exhaust pipe, and joins one outlet-side exhaust pipe.

In this diesel particulate filter device, the exhaust pressures of the exhaust gases discharged through the straight outlet pipe and the curved outlet pipe are adjusted to be equal to each other. For this reason, a throttle is provided in the straight exhaust pipe on the outlet side. Furthermore,
A throttle valve for restricting the flow of the exhaust gas is provided at a position downstream of the outlet-side exhaust pipe where the pressure sensor is installed, in order to properly detect the exhaust pressure in the installation area of the pressure sensor. Have been.

In this diesel particulate filter device, the noise generated by the flow of the exhaust gas is suppressed by the exhaust gas flowing from the exhaust pipe through the distribution housing and the filter housing to the outlet exhaust pipe. You.

Since this diesel particulate filter device is configured as described above, a throttle is provided in the straight outlet exhaust pipe to ensure uniformity with the exhaust pressure of the curved outlet exhaust pipe. A throttle valve is provided on the outlet side exhaust pipe to detect the pressure ratio between the exhaust pressure in the exhaust pipe on the upstream side of the filter and the exhaust pressure in the exhaust pipe on the downstream side at all times. It is possible to accurately control the collection state, the timing and period of switching between the switching valve and the switching valve, the timing and period of energization of the heater, and the operation of the EGR pump. The muffler is mounted in a space to be mounted instead of the muffler, and is mounted corresponding to the longitudinal direction of the vehicle to improve the mountability to the vehicle. In this diesel particulate filter device, whether the particulate matter is trapped to the limit or not depends on the exhaust pressure in the limit trapping state depending on the flow rate of the exhaust gas. By calculating the pressure ratio of the exhaust pressure to the above, the limit collection state of the particulate matter by the filter is detected. Also, when the flow rate of the exhaust gas on the outlet side increases and the exhaust pressure increases, the exhaust pressure becomes higher during the regeneration of the filter.
Helps the R pump.

The diesel particulate filter measures the resistance of the wire mesh heater and checks whether the wire mesh heater operates normally. In other words, when the heater is off, even if the particulate matter is collected by the filter, the collected particulate matter cannot be heated and incinerated to regenerate the filter. do. Further, when the regeneration of the filter is stopped halfway, the controller stores it as a hold and continues the regeneration of the filter in the next operation.
When the filter is regenerated, the temperature of the filter is detected.
Even if gas is sent into the filter, the temperature of the filter does not drop and the burning state of the particulate matter does not blow out.
An EGR gas containing oxygen is supplied to the filter.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a diesel particulate filter device according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic explanatory view showing one embodiment of a diesel particulate filter device according to the present invention,
2 is a graph for explaining a pressure ratio for detecting a trapped state of the filter by the pressure sensor shown in FIG.

This diesel particulate filter device has a function of collecting particulate matter such as carbon, HC and soot contained in exhaust gas discharged from a diesel engine and purifying the exhaust gas. Exhaust pipe 10 connected to the exhaust manifold
It is built in and installed. In this diesel particulate filter device, a pair of filter housings 1 and 2 and a distribution housing 3 interposed between the filter housings 1 and 2 are arranged so as to extend in the longitudinal direction. The pair of filter housings 1 and 2 and the distribution housing 3 extend in the longitudinal direction as a whole, and are formed so that they can be mounted instead of the muffler in a space where the muffler is mounted on the vehicle.

The distribution housing 3 has an exhaust pipe 10 on the inlet side.
The filter outlet 28 of the filter housing 1 is connected to the curved outlet side exhaust pipe 4, and the filter outlet 29 of the filter housing 2 is connected to the straight outlet side exhaust pipe 5. The curved outlet side exhaust pipe 4 and the straight outlet side exhaust pipe 5 join the outlet side exhaust pipe 11 at a junction 31. A pair of filter housings 1 and 2 have filter inlets 8 and 9 to which exhaust gas is supplied, opposed to each other, and filter outlets 28 and
29 are disposed in the longitudinal direction so as to be located on the opposite side. The distribution housing 3 is arranged between the filter housings 1 and 2 to form a distribution chamber 32 in which the filter inlets 8 and 9 are respectively opened, and the exhaust pipe 10 on the inlet side is connected.

The diesel particulate filter device includes filter bodies 24 and 25 disposed in the filter housings 1 and 2 for collecting particulates in exhaust gas, and particles provided on the filter bodies 24 and 25, respectively. Either one of the filter inlets 8 and 9 is opened to supply exhaust gas to a pair of filters 1F, 2F, and the filters 1F and 2F having heaters 26 and 27 made of a wire mesh or the like for heating and burning the curate, and the other is opened. The switching valve 12, which is switched to close the other filter inlets 8, 9 while sitting on valve seats 33, 34 provided at the filter inlets 8, 9, the exhaust pipe 11 on the outlet side and the filter housings 1, 2, A part of the exhaust gas flowing through the exhaust pipe 11 during regeneration of the EGR pipe 6 and the filters 1F and 2F, One of EG through R tube 6
A switching valve 13 provided on the EGR pipe 6 for switching to the R pipes 7A, 7B, and an EGR pipe 6 which is operated to supply exhaust gas to one of the filter housings 1 and 2 through the EGR pipe 6. The EGR pump 14 is provided. The EGR pipe 7A is connected to the filter housing 1
The EGR pipe 7B is connected to an EGR inlet 9A of the filter housing 2.
Further, the EGR pipe 6 is provided with a pressure sensor 17 for detecting the pressure of the EGR gas. Further, the switching valve 12 and the switching valve 13 include a position sensor (not shown) for detecting which side the open state is set to.

The filters 1F and 2F are filter housings.
Particles contained in the exhaust gas arranged in the
Filter bodies 24 and 25 for collecting rate, filter book
On the upstream and downstream surfaces of the exhaust gas of the bodies 24 and 25
A wire mesh having one of the heaters 26 and 27
It is composed of Filter bodies 24 and 25 are pleated
Folded into a cylindrical shape as a whole,
At both ends of the main bodies 24 and 25, shielding plates 40 and 41 are provided.
Is attached. The shielding plate 40 includes the filter 1F,
The entire surface on the entrance side of 2F is shielded, and the shielding plate 41 is
Inner exhaust gas passages 38, 39 on the outlet side of filters 1F, 2F
The portion excluding the region that constitutes is closed. filter
The main bodies 24 and 25 are made of heat-resistant and oxidation-resistant SiC,
Al_TwoO _Three, SiC coated Si_ThreeN_FourConsisting of
Made from ceramic fiber non-woven fabric and other uniform materials
Materials such as ceramic woven cloth and ceramic felt
Can be made from fiber materials. For fiber material, use single-length fiber material.
Not only can be used, but also
Is a nonwoven fabric laminated with crimped ceramic long fibers, or
Shall be a composite material of crown feathered fibers and / or crimped ceramic.
It can be composed of non-woven fabric laminated with Mick long fiber.
Wear.

The exhaust pipe 10 on the inlet side, the pressure sensor 15 for detecting the pressure value P ₁ of the exhaust pressure of the exhaust gas supplied to the filter 1F or filter 2F is provided. A pressure sensor 16 for detecting the pressure of the exhaust gas discharged from the filter 1F or the filter 2F is provided at the exhaust pipe 11 on the outlet side.
Is provided. A throttle valve 22 that provides a throttle effect to the flow of exhaust gas is provided in the outlet-side exhaust pipe 11 downstream of the pressure sensor 16 in order to appropriately generate the pressure value P ₂ of the exhaust pressure in the installation area of the pressure sensor 16. Have been. Throttle valve 2
2 can be configured so that the throttle can be adjusted to adjust the passage area. Further, in this diesel particulate filter device, exhaust gas discharged from the filter housing 2 through a straight outlet pipe 5 and exhaust gas discharged from the filter housing 1 through a curved outlet pipe 4 are provided. A throttle 23 is provided in the straight outlet pipe 5 in order to adjust the respective exhaust pressures with the exhaust gas to be equal to each other. In FIG. 1, in order to adjust the exhaust pressures discharged from the filter housing 1 and the filter housing 2 to be equal to each other, a filter outlet 2 is provided.
9 is provided with a throttle 23, but in order to exhibit the same function as the throttle 23, the diameter of the curved outlet side exhaust pipe 4 bypassing the filter outlet 28 and connected to the exhaust pipe 11 is increased. It can also be adjusted by making the diameter of the straight outlet side exhaust pipe 5 small.

In this diesel particulate filter device, if the collection of particulate matter by the filters 1F and 2F proceeds, the exhaust pressure P ₁ of the inlet side exhaust pipe 10 increases and the outlet side exhaust pipe increases even at the same load flow rate. The exhaust pressure P ₂ of No. 11 is almost the same as the exhaust pressure before the collection of the particulate matter. In FIG. 2, the horizontal axis represents the exhaust gas flow rate (N), and the vertical axis represents the exhaust pressure of the exhaust gas flowing through the filters 1F and 2F, that is, the pressure values P ₁ and P ₂ (mmHg). The pressure values P ₁ and P _{2 with} respect to the flow rate of the exhaust gas flowing through the exhaust pipes 10 and 11 are small when the flow rate of the exhaust gas is small, but become large when the load on the engine increases and the load flow rate increases. So filter 1
The limit value RP ₁ of the trapping capacity of F and 2F is the pressure ratio P ₁ / P ₂
By calculating and determining
The absolute amount of the trapped particulate matter of F and 2F can be detected. In FIG. 2, filter 1
F, 2F according represents the pressure value P ₁ as a maximum trapping state of particulates materials by curve A, the filter 1F, the pressure value P ₁ of the initial trapping state of particulates materials by 2F
Is indicated by the curve B, also shows filter 1F, the exhaust gas flowing through the exhaust pipe 11 downstream of 2F pressure value P ₂ by a curve C. Further, the maximum limit value of the particulate matter by the filter 1F is shown by a line D.

Accordingly, the limit value R of the trapping ability of the pressure ratio P ₁ / P _{2 to} the flow rate of the exhaust gas flowing through the exhaust pipes 10 and 11 is shown.
P ₁ is the pressure ratio a ₁ / a _{2 to} the exhaust gas flow rate a when the pressure values a ₁ and a ₂ are set to the exhaust gas flow rate a and the pressure values b ₁ and b ₂ are set to the exhaust gas flow rate b. And the pressure ratio b ₁ / b ₂ with respect to the exhaust gas flow rate b become a substantially equal value.
It can be set to P _1. Therefore, the controller 20
Calculates the pressure ratio P ₁ / P ₂ in response to the pressure values P ₁ and P ₂ of the detection signals of the pressure sensors 15 and 16 for detecting the trapping state of the particulate matter by the filters 1F and 2F, and calculates the value. by but by calculating whether reached the limit value RP ₁ for collecting state of particulates matter in the filter 1F, 2F, regardless of the exhaust gas flow rate,
It can be detected as a particulate matter trapping limit value by the filters 1F and 2F.

The controller 20 includes a filter 1
Heaters 26 and 27 provided on F and 2F, switching valve 1
2 and a motor 35 for driving the switching valve 13 and the EGR pump 14 provided in the EGR pipe 6. The motor 35 that drives the EGR pump 14 is provided with filters 1F and 2 according to the operating condition of the engine.
In order to adjust the EGR gas containing air necessary for the regeneration of F, the controller 20 is configured to control the rotation speed. The operating condition of the engine is detected by a rotation sensor 42 for detecting engine rotation and a load sensor 43 for detecting engine load. In some cases, the controller 20 may be configured to control each device according to a detection signal of a temperature sensor 19 provided in the exhaust pipe 10 on the upstream side of the filters 1F and 2F for detecting the temperature of exhaust gas. . In this case, the exhaust gas temperature is correlated with the magnitude of the engine load, and the higher the engine load and the higher the exhaust gas temperature, the lower the O ₂ concentration.

In this diesel particulate filter device, it is not preferable that the device itself cannot be operated due to the failure of the pressure sensors 15 and 16. Therefore, when the pressure sensors 15 and 16 fail, the device is set by setting a timer. The controller 20 is configured to be able to operate. The diesel particulate filter device includes pressure sensors 15, 16, 17, filters 1F, 2
In order to display the failure of the devices incorporated in the devices such as the heaters 26 and 27 and the EGR pump 14 provided in F, failure display means such as a failure display lamp and a failure display alarm are provided. The device is configured so that the failed device can be recognized by the means and the maintenance and repair are appropriately promoted. For example, the failure display means includes the pressure sensors 15, 1
6 and 17 failures are displayed intermittently and the heater 2
It is possible to configure to display the failures 6, 27 continuously.

This diesel particulate filter device collects particulates such as carbon, soot, and HC contained in the exhaust gas passing alternately through the filters 1F and 2F, and collects the particulates collected by the filters 1F and 2F. Is heated and incinerated by operating the heaters 26 and 27 of the upstream wire mesh or the downstream wire mesh as a heating heater, and the filter 1 is heated.
Play F and 2F. Further, in this diesel particulate filter device, the exhaust sound or noise generated by the flow of exhaust gas is such that the exhaust gas flows into the distribution housing 3 from the exhaust pipe 10 and expands. The air further expands and flows into the housings 1 and 2 and passes through the filters 1F and 2F set in the filter housings 1 and 2 to form the curved outlet-side exhaust pipe 4,
The sound is reduced by flowing to the straight outlet side exhaust pipe 5 and the exhaust pipe 11.

The EGR pipe 6 is connected to the exhaust pipe 11.
An EGR pump 14 is provided for supplying the purified exhaust gas to the filters 1F and 2F through the EGR pipe 6. The EGR pump 14 is driven by a DC motor 35 with DC power supplied from a battery or a generator 21, and the DC motor 35 is configured such that the rotation speed is controlled by the controller 20 according to the operating condition of the engine. . Although not shown, the EGR pump 14 partitions a housing that forms a pump chamber, a rotary shaft eccentrically and rotatably mounted in the housing, and a pump chamber formed by the housing and the rotary shaft into a plurality of compartments. Therefore, it is constituted by vanes biased by a spring force which are respectively arranged so as to be able to reciprocate in the axial direction of the rotating shaft. The EGR gas pressure of the EGR gas supplied to the filters 1 and 2 by driving the EGR pump 14 is equal to the pressure sensor 1.
7 and the proper EGR gas is
2 is supplied.

Further, in order to heat and incinerate the particulates collected in the filter bodies 24 and 25 of the filters 1F and 2F, an upstream wire mesh or a downstream wire mesh as heaters 26 and 27 provided in the filters 1F and 2F, respectively. Is provided. Electric power supplied from the battery or the generator 21 is supplied to the heaters 26 and 27 through the power supply terminal 18. Filter housings 1 and 2 and filter body 2
4, 25, the outer exhaust gas passages 36, 3 into which the exhaust gas flowing from the filter inlets 8, 9 expands and enters.
7 are formed. Further, inside the filter main bodies 24, 25, inner exhaust gas passages 38, 39 into which purified exhaust gas passing through the filter main bodies 24, 25 from the outer exhaust gas passages 36, 37 enters are formed.

The controller 20 includes the filter 1
F, upon 2F reproduction, as the amount of O ₂ in the EGR gas supplied filter 1F, the 2F (exhaust gas) becomes an appropriate amount, detected by the temperature sensor 19 provided upstream of the filter 1F, 2F The rotation speed of the DC motor 35 is controlled according to the detected value of the exhaust gas temperature. Further, during regeneration of the filters 1F and 2F, the controller 20 increases the rotation speed of the motor 35 when the load of the engine is high, sends a large amount of exhaust gas to the filters 1F and 2F, and reduces the rotation speed of the motor 35 when the load is low. Filter 1F, 2F
A small amount of exhaust gas is set to be controlled. The controller 20 includes filters 1F, 2F
The heaters 26 and 27 are energized in response to the collection of particulates equal to or greater than the predetermined amount, and the particulates collected by the filters 1F and 2F are heated and incinerated to remove the filters 1F and 2F. Control to play.

Next, an embodiment of the operation of the diesel particulate filter device will be described with reference to FIGS. 3, 4, 5 and 6. 3 to 6 are process flowcharts showing one embodiment of the operation of the diesel particulate filter device. The symbol S in S1 to S64 indicating a processing step in the processing flow diagram means a step.

As shown in FIG.
Whether the engine is idling by driving
(S1), and if the vehicle is not idling,
Proceeding to S14, when the engine is idling, the filter
When the heaters 26 and 27 of the 1F and 2F are energized, the resistance R_F1, R
_F2Is measured (S2, S5), and the resistance of the heaters 26, 27 becomes
Appropriate resistance range (minimum resistance R_OL~ Maximum resistance R_OH)
It is determined whether or not (S3, S4, S6, S7). heater
The resistance of 26 and 27 is R_OL<P₁<R_OH, R_OL<P_Two<R
_OH, The heaters 26 of the filters 1F and 2F,
27 functions normally, the base pressure of the pressure sensor 15
Value P₁And the basic pressure value P of the pressure sensor 16 _TwoMeasuring
(S8, S9). The resistance of the heaters 26 and 27 is R_OL<P₁
<R_OH, R_OL<P_Two<R_OHFunctioning properly but not in the range
If not, filter 1F and 2F
Even if the waste materials are collected, they cannot be regenerated by heating incineration.
It emits fault display means such as a fault light and an alarm, and filters 1F and 2
Stop collecting particulate matter in exhaust gas by F
Then, the control function of the device is stopped (S10). Equipment control
If the vehicle is running when the control function is stopped
At that time, it cannot be stopped and diesel putty
The vehicle cannot be driven due to a malfunction of the filter device.
In such an emergency, the controller
20 is an emergency valve (not shown) for emergency operation,
Bypass passage (not shown) that bypasses the first and second filters 1F and 2F
Control to allow the engine to be driven
So that repairs and replacement of parts can be performed.
(S65).

Next, the controller 20 detects whether the pressure sensors 15 and 16 are functioning normally or not, so that the pressure ratio P ₁ / P ₂ of the pressure values P ₁ and P ₂ of the pressure sensors 15 and 16 under no load. to calculate the P _2. Pressure ratio P ₁
Maximum pressure ratio RP which / P ₂ is the pressure ratio P ₁ / P ₂ has predetermined
Pressure range RP _L of _H and the minimum pressure ratio RP _L <(P ₁ / P
₂₎ <If RP _H, the pressure sensors 15 and 16 is normal, the process proceeds to S14, the pressure ratio P ₁ / P ₂
Are not within the predetermined pressure range, the pressure sensors 15, 16
Since the device has failed, a failure display means such as a failure light or an alarm is issued (S13). Therefore, even if the pressure sensors 15 and 16 are out of order, the filters 1F and 2F can process the particulate matter from the exhaust gas. Therefore, the control by the pressure sensors 15 and 16 is stopped, and the control is switched to the control by the timer. The process proceeds to S45.

When the pressure sensors 15 and 16 are normal,
It is detected whether or not the filters 1F and 2F were in the trapping state or the middle of the regeneration state (Hold-1, Hold-2) at the time of driving the engine (S14, S15). Filter 1
If F and 2F are Hold-1, Hold-2, the process proceeds to S16, and if not, Hold1 and Hold-2, the process proceeds to S23. In the processing step S16, the position sensor detects which of the filter 1F and the filter 2F the switching on / off valve 12 is open (S1).
6) It is determined whether or not the filter 1F is open (S
17) If the filter 1F is open, the process proceeds to S18. If the filter 2F is open, the process proceeds to S32.

As shown in FIG.
F, and the particulate matter in the exhaust gas is collected by the filter 1F. Further, the pressure sensors 15 and 16 measure the exhaust gas pressures P ₁ and P ₂ of the exhaust pipes 10 and 11 (S18, 19), and calculate the pressure ratio P ₁ / P ₂ (S18).
20). Then, whether the amount of particulate material which is trapped in the filter 1F has been collected a predetermined amount RP ₁ or more, determined by _{P 1 / P 2> RP 1} , P 1 / P 2>
The exhaust gas is purified by the filter 1F until RP ₁ is reached (S21).

When P ₁ / P ₂ > RP ₁ , the filter 1F is in a state where a predetermined amount of particulate matter has been collected. Is switched to the filter 2F side (S22). The exhaust gas flows to the filter 2F,
Particulate matter in the exhaust gas is collected by the filter 2F. Then, in order to heat and incinerate the particulate matter collected in the filter 1F, the heater 26 of the filter 1F is energized (S23), the particulate matter is ignited, and the filter 1F is detected by the temperature sensor 19.
Detecting the temperature T ₁ of the F. Temperature T ₀ of the temperature T ₁ is predetermined filter 1F (e.g., 600 ° C.) becomes more than, as well as confirm the state of particulates substance may be heated combustion, even if the process is Hold-1 (S2
5) Turn on the heater 26 of the filter 1F. Then,
The switching valve 13 is switched to the filter 1F side, the motor 35 is driven to operate the EGR pump 14, a part of the purified exhaust gas is sent to the filter 1F, and the O2 necessary for heating and burning particulate matter is heated. ₂ for supplying the (2
6).

Therefore, the exhaust pressure P _E1 of the exhaust gas in the EGR pipe 6 is detected by the pressure sensor 17, and it is determined whether or not a predetermined amount of exhaust gas is supplied to the filter 1F through the EGR pipe 6 at a predetermined exhaust pressure P _E0. (S27). When the exhaust pressure P _E1 is lower than the exhaust pressure P _E0 , the EGR pump 14
Since there is a possibility that is broken down, the process proceeds to S10, in which the heating and incineration of the particulate matter collected in the filter 2F is stopped, and the control function is stopped. P
_{If E1} > P _E0 , a timer is set (S28), the regeneration time t _C of the filter 1F is measured, and it is determined whether or not t _C has reached a predetermined regeneration time t _s1 (S29). ,
Even when the processing step is Hold-1, the regeneration time t _C of the filter 1F is measured (30).

As shown in FIG. 5, when the reproduction time t _C of the filter 1F reaches a predetermined reproduction time t _s1 , the filter 1F
Heater 26 is turned off since the regeneration of
Then, the operation of the EGR pump 14 is stopped, the switching valve 13 is shut off, and the timer is turned off (S31). Next, in order to detect the trapping state of the particulate matter in the exhaust gas by the filter 2F, the pressures P ₁ and P ₂ are measured by the pressure sensors 15 and 16 (S32, 33), and the pressure ratio P
Calculating a ₁ / P ₂ (S34). Next, filter 2F
The amount of the particulate matter collected in the vessel is a predetermined amount RP ₁
It is determined whether P ₁ / P ₂ > RP _{1 has} been collected as described above, and the exhaust gas is purified by the filter 2F until P ₁ / P ₂ > RP ₁ (S34).

When P ₁ / P ₂ > RP ₁ , the filter 2F is in a state where a predetermined amount of particulate matter has been trapped. Is switched to the filter 1F side (S35). The exhaust gas flows to the filter 1F,
The particulate matter in the exhaust gas is collected by the filter 1F. Therefore, in order to heat and incinerate the particulate matter collected by the filter 2F, the heater 27 of the filter 2F is energized (S36) to ignite the particulate matter, and the temperature sensor 19 filters the filter material.
Detecting the temperature T ₁ of the F. When the temperature T _{1 of the} filter 2F becomes equal to or higher than the predetermined temperature T ₀ , it is confirmed that the particulate matter can be heated and burned, and when the processing step is Hold-2 (S38), the heater 27 of the filter 2F is turned on. Is turned on. Next, the switching valve 13 is switched to the filter 2F side, the motor 35 is driven to operate the EGR pump 14, and a part of the purified exhaust gas is
F ₂ to supply O ₂ for heating and burning the particulate matter (39).

Therefore, the exhaust pressure P _E1 of the exhaust gas in the EGR pipe 6 is detected by the pressure sensor 17, and it is determined whether or not a predetermined amount of exhaust gas is supplied to the filter 2F through the EGR pipe 6 at a predetermined exhaust pressure P _E0. (S40). When the exhaust pressure P _E1 is lower than the exhaust pressure P _E0 , the EGR pump 14
Since there is a possibility that is broken, the process proceeds to S10, in which the heating and incineration of the particulate matter collected in the filter 1F is stopped, and the control function is stopped. P
_{If E1} > P _E0 , a timer is set (S41), the regeneration time t _C of the filter 2F is measured, and it is determined whether or not t _C has reached a predetermined regeneration time t _s1 (S42). ,
Even when the processing step is Hold-2, the reproduction time t _C of the filter 2F is measured (43). When the regeneration time t _C of the filter 2F reaches a predetermined regeneration time t _s1 , since the regeneration of the filter 2F has been completed, the heater 27 is turned off, the operation of the EGR pump 14 is stopped, and the switching valve 13 is shut off. Then, the timer is turned off (S44). Next, the state is switched to a state in which the particulate matter in the exhaust gas is collected by the filter 1F, the processing step returns to S1, and the above processing steps S1 to S44 are repeated.

As shown in FIG. 3, in step S13 of the processing step,
And the failure of the pressure sensors 15 and 16, the filter 1
Exhaust gas purification by F and 2F is controlled by timer
Is switched to the control as shown in FIG.
The roller 20 detects the position of the switching valve 12 (S4).
5). The switching on-off valve 12 is connected to either of the filters 1F and 2F.
The position sensor detects whether
(S46), the switching valve 12 opens to the filter 2F.
When it is in the state, the process proceeds to S47,
The on-off valve 12 is open to the filter 1F
At times, the process proceeds to S57. Change the switching valve 12
Set a timer to measure the time open to the router 2F
Then, the collection time by the filter 2F is measured (S4).
7). When a predetermined time has elapsed, the filter 2F
The specified amount of particulate matter has been collected.
Therefore, the exhaust gas flows from the filter 2F to the filter 1F.
The switching valve 12 is switched so that the
Collected by the filter 2F to perform the regeneration process of the filter 2F.
Filter to burn incinerated particulate matter
The heater 27 on the second floor is energized to add particulate matter.
Heat incineration (S48). Fill by temperature sensor 19
Temperature T₁Is detected, and a predetermined temperature T
₀Is determined (S49).

When the temperature T _{1 of the} filter 2F becomes equal to or higher than the predetermined temperature T ₀ , it is confirmed that the particulate matter can be heated and burned, the switching valve 13 is switched to the filter 2F, and the motor 35 is driven. The EGR pump 14 is operated to filter a part of the purified exhaust gas into the filter 2.
F to supply O ₂ for heating and burning the particulate matter (50). Therefore, the pressure sensor 17
The exhaust pressure P _E1 of the exhaust gas of the EGR pipe 6 is detected by
Whether or not a predetermined amount of exhaust gas is supplied to the filter 2F through the EGR pipe 6 is detected at a predetermined exhaust pressure P _E0 .
If the exhaust pressure P _E1 is lower than the exhaust pressure P _E0 , there is a possibility that the EGR pump 14 has failed.
Proceeding to 10, the heating and incineration of the particulate matter collected in the filter 2F is stopped, and the control function is stopped. If P _E1 > P _E0 , a timer is set (S52), and the regeneration time t _C of the filter 2F is measured.
_It is determined whether _C has reached a predetermined reproduction time t _s1 (S5).
3) When the regeneration time becomes t _C > t _s1 , the regeneration of the filter 2F is completed.
The operation of the GR pump 14 is stopped (S54).

Further, in order to measure the collection time t _f of the particulate matter by the filter 1F, a processing step S47 is performed.
It is determined whether or not the timer set in the step has reached a predetermined time _ts2 (S55). If t _f > t _s2 , the filter 1F is in a state where a predetermined amount of particulate matter has been collected. Therefore, the switching valve 12 is switched so that the filter 2F is opened, and the timer is set (S56). . Further, in order to heat and incinerate the particulate matter collected in the filter 1F, the heater 26 is energized and the filter 1F is turned on.
Of detecting the temperature T _1, it is determined whether or not has reached a predetermined temperature T ₀ determined in advance (S58). When the temperature T ₁ of the filter 1F reaches the temperature T ₀ or more (T ₁ > T ₀ ), the particulate matter collected by the filter 1F can ignite and burn, so that the EGR pump 14 is operated and the switching valve 13 is turned on. 1F, and a part of the purified exhaust gas is supplied to the filter 1F (S59).

Therefore, the EGR pipe is detected by the pressure sensor 17.
Exhaust gas exhaust pressure P of 6_E1Through the EGR pipe 6
The specified amount of exhaust gas is supplied to the filter 2F
A predetermined exhaust pressure P which is determined in advance_E0Based on
It is turned off (S60). Exhaust pressure P _E1Is the exhaust pressure P_E0Lower place
EGR pump 14 may have failed
Therefore, the process proceeds to S10, where the dust is collected on the filter 2F.
Stopped incineration of particulate matter
And stop the control function. Also, P_E1> P_E0In the case of
Sets the timer (S61) and reproduces the filter 1F
Time t_CIs measured and t_CIs the predetermined playback time t_s1Reached
It is determined whether or not the playback time is t (S62)._C> T_s1Nana
Then, the regeneration of the filter 1F is completed.
To the EGR pump 14, the operation of the EGR pump 14 is stopped,
The timer for the reproduction process is turned off (S63). Next
And the particulates in the exhaust gas by the filter 2F
In order to detect the collection time of the substance, the setting in processing step S56 is performed.
Collection time t by the set timer _fAt the specified time
Interval t_s2Is determined (S64). filter
Collection time t by 2F_fIs a predetermined time t_s2When you reach
The processing step proceeds to S1, and the above processing steps S1 to S64 are performed.
Repeat.

[0051]

According to the diesel particulate filter device of the present invention, as described above, by arranging a pair of filters in the longitudinal direction, one of the exhaust pipes on the outlet side is formed into a straight pipe and the other is formed into a curved pipe which bypasses the other. However, since the straight pipe is provided with a throttle, the exhaust gas pressure on the outlet side can be adjusted to the same pressure on both sides of the filter.
A switching valve that can solve the problem of the exhaust gas pressure from the structure, always detect the exact pressure ratio of the exhaust pressure, accurately detect the trapped state of the particulate matter, and switch the flow of the exhaust gas; The switching timing of the switching valve for switching the supply of the EGR gas to the filter for the regeneration of the filter can be appropriately controlled. When mounted on a vehicle, this diesel particulate filter device can be installed, for example, in place of a muffler to purify exhaust gas and to have a function to muffle exhaust noise. Compact and easy to install.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing one embodiment of a diesel particulate filter device according to the present invention.

FIG. 2 is a graph illustrating a pressure ratio for detecting a trapped state of a filter by the pressure sensor of FIG. 1;

FIG. 3 is a process flowchart showing an operation process of the diesel particulate filter device of FIG. 1;

FIG. 4 is a process flowchart showing an operation process following the operation process of FIG. 3;

FIG. 5 is a process flowchart showing an operation step following the operation step of FIG. 4;

FIG. 6 is a processing flowchart showing an operation step following the operation step of FIG. 5;

FIG. 7 is a schematic explanatory view showing a conventional diesel particulate filter device.

[Explanation of symbols]

 1, 2 filter housing 1F, 2F filter 3 distribution housing 4 curved outlet side exhaust pipe 5 straight outlet side exhaust pipe 6, 7A, 7B EGR pipe 8, 9 filter inlet 8A, 9A EGR inlet 10 inlet side exhaust pipe 11 outlet Side exhaust pipe 12 Switching valve 13 Switching valve 14 EGR pump 15, 16, 17 Pressure sensor 19 Temperature sensor 20 Controller 22 Throttle valve 23 Throttle 24, 25 Filter body 26, 27 Wire mesh heater 28, 29 Filter outlet 30 Actuator 32 Distribution chamber 35 Motor 36, 37 Outer exhaust gas passage 38, 39 Inner exhaust gas passage

Claims (18)

[Claims] 1. A filter body for collecting particulate matter contained in exhaust gas discharged from an engine through an exhaust pipe, and a heater provided on the filter body for heating and burning the particulates. A pair of filters, a switching valve for opening and closing one of the filters and closing the other, an EGR pipe connecting the exhaust pipe on the outlet side of the filter and the filter, and the filter. A switching valve provided in the EGR pipe for supplying a part of the exhaust gas flowing through the exhaust pipe on the outlet side to one of the filters through the EGR pipe during regeneration of the EG.
Inlet pressure sensor for detecting the exhaust pressure P ₁ of the exhaust gas provided EGR pump which is operated for through R pipes supplying the exhaust gas into the filter, the exhaust pipe on the inlet side, an outlet side pressure ratio the outlet-side pressure sensor for detecting the exhaust pressure P ₂ of the exhaust gas provided in the exhaust pipe and that the exhaust pressure P _1, the pressure ratio P ₁ / P ₂ which is calculated from P ₂ are predetermined in The switching valve and the switching valve are actuated in response to being within the range and being equal to or higher than the predetermined pressure ratio, and the heater is energized and the EGR pump is actuated to supply the EGR pump with the EGR pump. A diesel particulate filter device comprising: a controller for supplying a gas to heat and incinerate the particulate matter trapped in the filter to regenerate the filter. 2. The controller according to claim 2, wherein said controller supplies electricity to said heater and responds to the fact that a resistance value of an electric system of said heater is within a predetermined resistance value range. 2. The control system according to claim 1, further comprising: activating a control function for trapping a substance, displaying a failure indicating means of the electric system in response to being out of the resistance value range, and performing control to stop the control function. The diesel particulate filter device as described in the above. 3. The controller according to claim 2, wherein the controller stores the filter being regenerated in response to the filter being regenerated, and performs control to start regeneration of the filter at the next operation. 2. The diesel particulate filter device according to 1. 4. The controller according to claim 1, wherein the controller stores the filter being regenerated in response to the filter being regenerated, and controls to start regeneration of the filter at the next operation. 2. The diesel particulate filter device according to 1. 5. The controller, in response to a detected temperature from a temperature sensor for detecting a temperature of the filter being equal to or higher than a predetermined temperature, stopping the energization of the heater and operating the EGR pump, 2. The diesel particulate filter device according to claim 1, comprising controlling to supply the EGR gas to the filter to be regenerated. 6. The controller according to claim 1, wherein the controller stops energizing the heater to stop the regeneration operation of the filter after the regeneration time of the filter has passed a predetermined time.
2. The diesel particulate filter device according to claim 1, further comprising a control for stopping a GR pump and operating the switching valve. 7. The controller according to claim 1, wherein the pressure ratio P ₁ /
_2. The diesel particulate according to claim 1, further comprising: displaying fault display means of the pressure sensor in response to P2 being outside the pressure ratio range, and switching to control by a timer instead of the pressure sensor. Filter device. 8. The controller turns on a timer, detects the positions of the switching valve and the switching valve, measures the collection elapsed time by the filter using the timer, and determines a predetermined collection time. When the elapsed time has elapsed, the switching on / off valve and the switching valve are operated to switch the flow of the exhaust gas from one of the filters to the other, and to heat and incinerate the particulate matter collected by the filter. While energizing the heater, the EGR
8. The diesel particulate filter device according to claim 7, comprising controlling operation of a pump to supply the EGR gas to the filter on the regeneration side. 9. The filter body according to claim 1, wherein the filter body is formed by folding a laminated material of ceramic fibers into a fold shape so as to form a cylindrical shape as a whole, and the exhaust gas flows from the outside to the inside of the filter body. 2. The diesel particulate filter device according to item 1. 10. The diesel particulate filter device according to claim 1, wherein a rotation speed of the motor driving the EGR pump is controlled by the controller in accordance with an operation state of the engine. 11. The switching on-off valve and the switching valve are provided with a position sensor for detecting a set position, and the controller switches between the switching on-off valve and the switching valve in response to a detection signal of the position sensor. 2. The diesel particulate filter device according to claim 1, comprising controlling a switching operation. 12. The controller according to claim 1, wherein the controller detects an exhaust gas temperature by a temperature sensor provided upstream of the filter so that an O ₂ amount in the exhaust gas supplied to the filter at the time of regeneration of the filter becomes an appropriate amount. 11. The diesel particulate filter device according to claim 10, comprising controlling a rotation speed of the motor according to a value. 13. The controller according to claim 1, wherein the controller increases the number of rotations of the motor when the load of the engine is high and sends a large amount of exhaust gas to the filter, and reduces the number of rotations of the motor when the load is low. The diesel particulate filter device according to claim 10, further comprising controlling to send a small amount of the exhaust gas to the filter. 14. The filter is arranged in a pair of filter housings arranged longitudinally on both sides of a distribution housing forming a distribution chamber to which the exhaust pipe is connected,
2. The diesel particulate filter device according to claim 1, wherein filter inlets of the filter housing face each other and open to the distribution chamber, and a filter outlet of the filter housing is located on an opposite side of the filter inlet. . 15. The filter outlet of the filter housing, one of which is connected to a straight outlet-side exhaust pipe and the other is connected to a curved outlet-side exhaust pipe, and merges into one outlet-side exhaust pipe. The diesel particulate filter device according to claim 14, comprising: 16. In order to adjust the respective exhaust pressures of the exhaust gas discharged through the straight-shaped outlet-side exhaust pipe and the curved outlet-side exhaust pipe to be equal to each other, the straight-shaped outlet-side exhaust pipe may be adjusted to be equal to each other. 15. The diesel particulate filter device according to claim 14, wherein a throttle is provided in the outlet-side exhaust pipe. 17. A throttling effect on the flow of the exhaust gas at a position downstream of the outlet-side exhaust pipe where the pressure sensor is installed, in order to properly detect the exhaust pressure in the installation area of the pressure sensor. 14. The diesel particulate filter device according to claim 13, further comprising a throttle valve provided. 18. The noise generated by the flow of the exhaust gas is muted by the exhaust gas flowing from the exhaust pipe through the distribution housing and the filter housing to the outlet exhaust pipe. Item 14. A diesel particulate filter device according to item 13.