JP2004003400A - Filter regeneration fitment in internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter regeneration fitment in successful internal combustion engine having good efficiency of combustion or regeneration efficiency in which a micronization of fuel as for combustion for reproduction of the filter 2 for waste gas purification, is made for fuel not to remain in piping of burner 6 in liquid form or gaseouos state, and conditioning for output of burner 6 can be performed for easy combustion. <P>SOLUTION: A high-speed waste gas or air stream is made. An aspirator mechanism (suction equipment style) is adopted as a jet point of the burner 6. Spillover section of fuel in the negative pressure status is maintained. Thus, a bypass tube 5 prepared in an exhaust conduit 1 of waste gas, the aspirator burner 6 attached in the bypass tube 5, fuel supply tube 7 to the aspirator burner 6, and a plug 8 for ignition for ignition fuel applied to the aspirator burner 6 from the fuel supply tube 7, are provided. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a filter regeneration device for an internal combustion engine, and more particularly to a filter regeneration device for a diesel engine and other internal combustion engines.
[0002]
[Prior art]
BACKGROUND ART Conventional diesel engines and other internal combustion engines are provided with a diesel particulate collection device such as a filter for removing diesel particulates (PM) and other particulate matter in exhaust gas.
In recent years, with the growing interest in global environmental problems, including the problem of suspended particulate matter in the atmosphere, research and development of PM reduction technologies from diesel engines, etc., and at the same time, diesel particulates as post-treatment of exhaust gas A filter (DPF) is being developed.
Therefore, it is necessary to remove PM and other particulate matter collected by the DPF from the filter and regenerate the filter.
[0003]
The DPF regeneration method includes regeneration using an electric heater, regeneration using a catalyst, and regeneration using a light oil burner.
Regeneration by an electric heater has a problem in that it is not suitable for a filter having a large thermal conductivity, which has a limitation in supply power and dissipates heat.
There is a problem that regeneration with a catalyst is not suitable under running conditions where the exhaust temperature of the engine is low.
On the other hand, the regeneration by the light oil burner can end the regeneration in a relatively short time by giving a high heat value. A light oil burner that directly burns fuel to convert it to heat is more energy-saving than an electric heater that uses electric power, which has a large number of energy conversions, as an energy source.
[0004]
However, a gas oil burner using a liquid fuel such as gas oil has a problem that atomization required for combustion for regeneration cannot be sufficiently obtained because an injector or the like cannot be directly attached to a high-temperature exhaust system. .
In addition, since the burner output for raising the temperature of the exhaust gas varies depending on the operating conditions of the engine, particularly the number of revolutions, it is difficult to adjust the output.
Further, if the fuel remaining in the burner pipe is left as it is at the end of the burner operation, the fuel is carbonized by the heat of the exhaust gas, and the fuel treatment of the burner pipe becomes incomplete, which is not preferable in terms of reliability.
[0005]
In addition, a light oil evaporation burner that uses gaseous gas obtained by evaporating light oil as a fuel also has an advantage for regeneration by an electric heater and regeneration by a catalyst, similarly to the above-described light oil burner, but has an advantage in engine operation. Since the output of the evaporative burner for raising the temperature of the exhaust gas varies depending on the conditions, particularly the number of revolutions, it is difficult to adjust the output.
Further, if the gas remaining in the evaporative burner pipe is left as it is at the end of the evaporative burner operation, the gas is cooled and liquefied, and then carbonized or contaminated by the inflow of exhaust gas, resulting in incomplete gas treatment of the evaporative burner pipe. Therefore, there is a problem that reliability is not preferable.
[0006]
It is generally very difficult to employ the light oil burner or light oil evaporation burner described above as a DPF regeneration burner and directly supply fuel spray to the exhaust pipe. This is because the exhaust pipe is always in a high temperature state, and there is no medium contributing to the cooling of the burner around. Therefore, it is difficult to use an injector for supplying fuel spray or a nozzle for intermittent injection.
When an injector or a nozzle for intermittent injection is used, the following problems are expected.
When an injector is used, there are problems such as breakage due to welding of the working coil and fuel leakage due to erosion of the resin portion.
When the nozzle for intermittent injection is used, there is a problem that injection is impossible or continuous injection due to sticking of the sliding portion of the needle valve.
The only configuration that is considered to be feasible is the air-assist system, in which fuel injected away from the exhaust pipe is transported through a pipe by compressed air and injected. However, even with this method, a large amount of compressed air is required, which not only increases the size of the apparatus, but also causes fuel to adhere to the inner surface of the pipe in the course of transportation, and the injection stability is not very good. Also, at the end of the injection, it is necessary to keep the compressed air flowing to discharge the fuel from the inner surface of the pipe. After that, since exhaust gas flows into the pipe, there is a problem that contamination of the inner surface cannot be denied.
[0007]
In addition, when an intermittent injector is used in the fuel supply system of the fuel evaporator for the light oil evaporation burner, it is easy to change the injection amount per unit time by changing the injection pulse time and injection cycle. Although controllable, the instantaneous flow rate of the evaporative gas varies. With such evaporative gas, stable combustion cannot be expected, and the fuel supply system to the evaporator needs to be a continuous flow.
[0008]
Further, the output required for a burner such as a light oil burner or a light oil evaporation burner differs depending on the operating conditions of the engine.
In general, the higher the engine speed, the higher the exhaust gas flow rate. Also, the higher the load, the higher the exhaust gas temperature. Therefore, if the output of the burner is constant, the combustion temperature may be too high depending on the operating condition, causing the filter to burn out or not reaching the temperature for burning PM.
That is, it is considered that a mechanism for adjusting the output of the burner is indispensable. However, the temperature control can be controlled by adding a temperature sensor such as a thermocouple to the filter.
[0009]
It is to be noted that the treatment of the evaporated gas and the fuel in the fuel pipe when the burner is stopped is an important problem affecting the reliability of the regenerator. For example, if the fuel evaporator is also stopped at the same time as the light oil evaporation burner is stopped, the remaining gas that could not be jetted is cooled and liquefied. Liquid fuel also exists in the evaporator. Alternatively, if exhaust gas flows into the atmosphere, the occurrence of internal contamination and carbonization can easily be imagined. That is, it is necessary to adopt a configuration in which the evaporated gas and the fuel in the fuel pipe are completely discharged, and the exhaust gas does not flow.
[0010]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and has as its object to provide a filter regeneration device for an internal combustion engine that can effectively regenerate a filter such as a DPF (diesel particulate filter).
[0011]
Another object of the present invention is to provide a filter regeneration device for an internal combustion engine that can sufficiently atomize fuel for combustion for regeneration of a filter.
[0012]
Another object of the present invention is to provide a filter regeneration device for an internal combustion engine that can easily adjust the output of a burner for combustion.
[0013]
Another object of the present invention is to provide a filter regeneration device for an internal combustion engine that can prevent fuel from remaining in a liquid state or a gas state in a pipe of a burner.
[0014]
Another object of the present invention is to provide a filter regenerating apparatus for an internal combustion engine that can reliably regenerate a filter using a light oil burner or a light oil evaporation burner with a simple configuration.
[0015]
Another object of the present invention is to provide a filter regeneration device for an internal combustion engine having good combustion efficiency or regeneration efficiency.
[0016]
[Means for Solving the Problems]
That is, the present invention creates a high-speed exhaust gas or air flow, employs an aspirator mechanism (aspirator mechanism) at the ejection part of a light oil burner or a light oil evaporation burner, and always creates a negative pressure at the liquid or gaseous fuel outlet. A filter regeneration device for an internal combustion engine that regenerates a filter for purifying exhaust gas of an internal combustion engine, wherein the filter regeneration device is provided in an exhaust pipe of the exhaust gas. A bypass pipe, an aspirator burner attached to the bypass pipe, a fuel supply pipe opening to the aspirator burner, and an ignition plug for igniting fuel supplied from the fuel supply pipe to the aspirator burner. A filter regeneration device for an internal combustion engine, characterized in that:
[0017]
The aspirator burner includes a reducing part that contracts from the exhaust pipe, a negative pressure chamber facing the reducing part, and a metering orifice that can supply the fuel from the fuel supply pipe facing the negative pressure chamber. , Can be provided.
[0018]
A switching valve for changing the flow path area of the exhaust pipe may be provided on the upstream side of the aspirator burner.
[0019]
The bypass pipe can be opened upstream of a switching valve that makes the flow path area of the exhaust pipe variable.
[0020]
The fuel supply pipe may be capable of supplying an evaporative gas of the fuel.
[0021]
The fuel evaporation mechanism may be provided between the fuel tank for the fuel and the fuel supply pipe.
[0022]
In the filter regeneration device for an internal combustion engine according to the present invention, a high-speed exhaust gas or air flow is created by utilizing the exhaust gas by a bypass pipe, and an aspirator burner is adopted at a fuel ejection portion from a fuel supply pipe, and the fuel is discharged. The fuel can be maintained in a negative pressure state at all times, so that the ejected fuel is atomized by a high-speed airflow, ignited by an ignition plug, and burned to produce diesel particulates in a filter by combustion. PM) Other particulate matter can be removed. Further, by controlling the negative pressure at the fuel outlet, the output of the burner can be adjusted.
In addition, since the ejection portion is always at a negative pressure, the fuel remaining in the burner pipe is reliably discharged, and the problem that the remaining fuel is carbonized is also solved.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a filter regeneration device for an internal combustion engine according to a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a cross-sectional view of a filter 2 and a filter regeneration device 3 attached to an exhaust pipe 1 of an internal combustion engine such as a diesel engine. The fine particles are collected and purified, and when they become clogged, they are heated and regenerated by the filter regenerating device 3.
[0024]
The filter regeneration device 3 includes a switching valve 4, a bypass pipe 5, an aspirator burner 6, a fuel supply pipe 7, and an ignition plug 8.
The filter regeneration device 3 employs, for example, a switching regeneration system for switching between the operation of the engine and the regeneration of the filter 2. The filter regeneration device 3 uses exhaust gas as a fluid for the aspirator burner 6, and uses a fuel supply pipe 7 for combustion. Supply of fuel.
[0025]
The switching valve 4 is provided in the exhaust pipe 1 and opens and closes the exhaust pipe 1 and the bypass pipe 5 appropriately to change the flow path area of the exhaust pipe 1. Distribute the flow rate of the exhaust gas in an appropriate ratio.
That is, during operation of the engine, most of the exhaust gas in the exhaust pipe 1 flows in the direction of the filter 2 as it is, and a small flow rate is branched to the bypass pipe 5. When the filter regeneration unit 3 regenerates the filter 2, the passage of the exhaust pipe 1 is closed at a predetermined ratio, and the exhaust gas flows toward the bypass pipe 5. However, it is not necessary to completely shut off the exhaust pipe 1 at the time of this regeneration as well, so that a part of the exhaust pipe 1 flows to the bypass pipe 5 and another part flows to the aspirator burner 6.
[0026]
The bypass pipe 5 bypasses the exhaust pipe 1 of the exhaust gas, is opened on the upstream side of the switching valve 4, and has an aspirator burner 6 and a fuel supply pipe 7 attached to a downstream end thereof.
[0027]
The aspirator burner 6 is, for example, a light oil burner, which is attached to the distal end portion (connection pipe portion 9) of the bypass pipe 5, and is located downstream of the switching valve 4 in the exhaust pipe 1. 2 shows an enlarged sectional view of the aspirator burner 6.
As shown in FIG. 2, the aspirator burner 6 includes a connection pipe 9 of the bypass pipe 5, an aspirator body 10, a support stay 11, a contraction member 12, and a collision plate 13.
[0028]
The connection pipe section 9 guides exhaust gas or air or other fluid from the bypass pipe 5 to the contraction member 12 of the aspirator burner 6.
[0029]
The aspirator body 10 has a flow contracting member 12 attached to the upstream side, a collision plate 13 fixed to an end on the downstream side, a reduction section 14 by the flow contracting member 12, a negative pressure chamber 15 (mixing chamber) at the outlet thereof, And an enlarged portion 16, and a metering orifice 17 that connects the fuel supply pipe 7 and the negative pressure chamber 15 is formed at a portion where the fuel supply pipe 7 is attached.
[0030]
The support stay 11 fixes the aspirator burner 6 (aspirator body 10) to the exhaust pipe 1.
[0031]
The contraction member 12 introduces exhaust gas by the reduction portion 14 to increase the flow velocity, so that the negative pressure chamber 15 is always in a negative pressure state as long as there is a flow of the fluid, and together with the negative pressure chamber 15 and the metering orifice 17. A fuel aspirator 18 (aspirator) from the fuel supply pipe 7 is configured.
That is, the negative pressure chamber 15 is in a negative pressure state under any engine operating conditions, and the value of the negative pressure in the negative pressure chamber 15 increases as the introduced flow rate increases. However, when the flow velocity reaches the sonic velocity, it does not decrease below the negative pressure at that time.
[0032]
The collision plate 13 is located downstream of the enlarged portion 16.
The fuel ejected from the metering orifice 17 is sheared by the high-speed airflow, is atomized, and is ejected through the expansion section 16 by the airflow. However, this spray has a strong penetration force and cannot be said to have a good diffusibility. Therefore, the collision plate 13 is placed on the downstream side of the jetting portion, and the fuel gas colliding with the spray plate is made to collide with the collision plate 13 to weaken the penetration force. The ignition is performed by the ignition plug 8 on the downstream side in order to improve atomization and diffusion.
[0033]
An assembly of heat-resistant wires 19 is arranged between the ignition plug 8 and the filter 2 so that heat from the aspirator burner 6 can be uniformly supplied to the filter 2 on the downstream side. The heat-resistant wire 19 does not provide flow resistance.
[0034]
The metering orifice 17 communicates the fuel supply pipe 7 with the negative pressure chamber 15 so that the fuel supply pipe 7 can be opened to the aspirator burner 6 via the metering orifice 17 and the amount of fuel supplied can be adjusted. .
That is, the amount of fuel flowing from the metering orifice 17 to the negative pressure chamber 15 is determined by the diameter of the metering orifice 17, the oil supply pressure, and the differential pressure value of the negative pressure. That is, as the negative pressure increases, the amount of fuel injected increases, and the output of the aspirator burner 6 increases.
[0035]
The aspirator 18 thus has a function of atomizing and diffusing the fuel in the aspirator burner 6, and also makes the negative pressure state of the negative pressure chamber 15 variable according to the flow rate of the exhaust gas according to the operating state of the engine. can do.
[0036]
Although not shown, a measurement mechanism or a sensor for measuring the temperature, pressure, residual oxygen concentration, or the like is provided inside or at the rear of the filter 2 or any other position to control the switching to the regeneration mode or the operation mode. And any other control can be performed.
[0037]
FIG. 3 is a schematic diagram of a fuel supply mechanism 20 that supplies fuel to the fuel supply pipe 7. The fuel supply mechanism 20 turns on / off a fuel tank 21, a fuel pump 22, a pressure regulator 23, and a fuel supply. It has an electromagnetic valve 24 and a fuel supply pipe 7.
[0038]
The fuel pump 22 was operated to feed the fuel from the fuel tank 21 under pressure, and the excess fuel was returned to the fuel tank 21 by the pressure regulator 23 to maintain the fuel pressure between the fuel pump 22 and the pressure regulator 23 constant. In this state, fuel can be supplied at a predetermined pressure to the fuel supply pipe 7 and the aspirator burner 6 via the electromagnetic valve 24, and fuel is supplied to the aspirator burner 6 at a predetermined oil supply pressure only when the aspirator burner 6 is operated. You. That is, the fuel pump 22 operates only when the aspirator burner 6 operates, and does not operate during normal operation.
In order to further finely adjust the output of the aspirator burner 6, a pressure variable mechanism (not shown) can be provided in the fuel piping system of the fuel supply mechanism 20.
[0039]
The ignition plug 8 (FIG. 1) is provided at an arbitrary position downstream of the aspirator burner 6 to ignite fuel spray from the aspirator burner 6 and generate combustion. Use a glow plug or any other plug. The ignition plug 8 may be provided on the upstream side of the filter 2 as shown in the illustrated example, or may be provided on the downstream side.
[0040]
In the filter regeneration device 3 having such a configuration, the switching valve 4 (FIG. 1) is closed during the regeneration of the filter 2 from the normal operation of the engine. However, the switching valve 4 is not completely closed, but a certain degree of opening is secured to secure the amount of combustion oxygen to the aspirator burner 6 during regeneration.
When the switching valve 4 is closed, the pressure of the exhaust gas introduction portion on the upstream side of the switching valve 4 increases, and the exhaust gas is easily introduced into the aspirator burner 6 via the bypass pipe 5 at a predetermined flow rate.
Note that, even during operation of the engine with the switching valve 4 open, the exhaust gas is always supplied to the aspirator through the bypass pipe 5 because the pressure at the inlet to the bypass pipe 5 is high by the pressure loss caused by the switching valve 4. It flows inside the burner 6, and the negative pressure chamber 15 maintains a negative pressure state.
[0041]
When the filter 2 is regenerated, the solenoid valve 24 of the fuel supply mechanism 20 is turned on to open it, and the fuel can be supplied from the fuel tank 21 by the fuel pumping by the fuel pump 22.
The exhaust gas flowing into the aspirator burner 6 makes the negative pressure chamber 15 a negative pressure, atomizes the fuel ejected from the fuel supply pipe 7 into the negative pressure chamber 15 through the metering orifice 17, and forms the fuel with the collision plate 13. The filter 2 is diffused, ignited by the ignition plug 8 to generate combustion, and the filter 2 is heated via the heat-resistant wire 19 to burn out PM and other fine particles collected by the filter 2 to regenerate the filter 2. Do.
[0042]
In the filter regeneration device 3, the flow rate of the exhaust gas guided into the aspirator burner 6 (aspirator 18) increases as the engine speed increases, so that the negative pressure in the aspirator 18 (negative pressure chamber 15) increases. That is, the amount of fuel flowing out when the aspirator burner 6 is operated increases, and the output thereof can be increased.
[0043]
In the present invention, the fuel supplied to the aspirator burner may be in a liquid state or a gasified fuel in a gas state.
That is, FIG. 4 is a schematic diagram of the filter regeneration device 30 and the fuel supply mechanism 20 according to the second embodiment of the present invention. In this filter regeneration device 30, the space between the solenoid valve 24 and the fuel supply pipe 7 is shown. , A fuel evaporating mechanism 31 is provided.
[0044]
FIG. 5 is a cross-sectional view of the fuel evaporating mechanism 31, and FIG. 6 is a side view of the fuel-evaporating mechanism 31 as viewed from the advancing direction of the vehicle equipped with the engine. And three heating glow plugs 33 and a wick 34 arranged at the interruption and upper stages, respectively.
[0045]
The evaporating mechanism housing 32 forms a fuel introduction part 35 and a metering orifice 36 from the electromagnetic valve 24 and a fuel lead-out part 37 to the fuel supply pipe 7 and communicates the fuel introduction part 35 and the fuel lead-out part 37. The three plug accommodating portions 38 formed in the lower, interrupted, and upper stages, respectively, and three communication passages 39 that sequentially connect the plug accommodating portions 38 from the lower stage to the upper stage are formed.
[0046]
Each of the heating glow plugs 33 has a connection terminal portion 40, a threaded portion 41, and a heating portion 42 (sheath portion), and is placed horizontally in the plug accommodating portion 38, that is, arranged in a horizontal state. Are arranged vertically. The wick 34 contacts the heating unit 42, and the fuel penetrates the wick 34 to increase the fuel heating efficiency.
A fuel passage formed by the metering orifice 36, the plug accommodating portion 38, the communication passage 39, and the fuel outlet portion 37 meanders in one direction in the evaporating mechanism housing 32 to form the fuel passage. 42 so that it can be in contact over the maximum length.
[0047]
The heating glow plug 33 uses, for example, a nickel (Ni) wire or an iron (Fe) wire, and FIG. 7 is a graph showing the relationship between the temperature of the heating glow plug 33 and the resistance ratio.
A constant voltage is supplied to the heating glow plug 33 to heat the heating unit 42. However, this supply voltage is a voltage value that can be maintained at a temperature of 1000 ° C. or less at which no disconnection of the coil occurs even when there is no heat absorbing portion around the heating glow plug 33.
In such a heating glow plug 33, when liquid fuel is present around it, the coil temperature is low, the coil resistance is small, and a large current flows, and therefore, the output of the heating glow plug 33 is large. Further, when there is no heat absorbing portion in the peripheral portion, the output becomes the minimum value while the heating portion 42 is kept at a high temperature state, so that the evaporation output can be automatically corrected.
[0048]
The wick 34 is made of heat-resistant wire mesh, fibrous or porous metal such as heat-resistant stainless steel, or porous ceramic, or the like, and efficiently supplies liquid fuel to the heating section 42 of the heating glow plug 33. Contact and promote its gasification. The wick 34 desirably does not contact the inner wall surface of the plug accommodating portion 38 of the evaporating mechanism housing 32 so that heat is not taken by the evaporating mechanism housing 32.
[0049]
Heating section 42 is heated to a predetermined temperature by supplying electricity from connection terminal section 40. The liquid fuel supplied from the fuel introduction section 35 and the metering orifice 36 at the bottom and soaked into the wick 34 is heated. However, when the inflow amount of the liquid fuel is large, the liquid fuel may be supplied in a state of being warmed at the bottom.
The fuel from the metering orifice 36 at the bottom (uppermost stream) reaches the lower communication path 39 which opens to the innermost part of the lower plug housing section 38, and further reaches the middle heating section 42, where the last plug is connected. When the fuel exits from the storage section 38 to the fuel outlet section 37, it is in a gaseous state.
[0050]
As shown in FIGS. 5 and 6, the fuel evaporating mechanism 31 directs the connection terminal 40 side of the heating glow plug 33 toward the traveling direction of the vehicle, that is, positions the heating unit 42 on the rear side in the traveling direction. As a result, the heat radiation area is reduced as much as possible, and the cooling of the heating section 42 by the air blow to the fuel evaporating mechanism 31 accompanying the running of the vehicle is suppressed as much as possible.
[0051]
Further, the configuration itself of the aspirator burner 43 in the filter regenerator 30 (FIG. 4) is substantially the same as the aspirator burner 6 (FIG. 2) in the filter regenerator 3 (FIG. 1) except for a part thereof. The fuel supplied through 7 is a fuel vapor. That is, the aspirator burner 43 is a light oil evaporation burner.
FIG. 8 is an enlarged sectional view of the aspirator burner 43. The aspirator burner 43 has a simple opening window 44 facing the negative pressure chamber 15 instead of the metering orifice 17 in the aspirator burner 6 of FIG. The function of the metering orifice 17 is performed by the metering orifice 36 in the fuel evaporation mechanism 31 shown in FIG.
[0052]
In the filter regeneration device 30 having such a configuration, similarly to the above-described filter regeneration device 3 (FIG. 1), the fuel gas is further atomized by the aspirator burner 43 (the aspirator 18), diffused, and ignited by the ignition plug 8. , Filter 2 can be reproduced.
[0053]
In particular, since the fuel supplied to the aspirator burner 43 is in a gaseous state, its combustion state or combustion characteristics are good, and the regeneration efficiency of the filter 2 can be improved.
[0054]
Even if the solenoid valve 24 in the fuel supply mechanism 20 is turned off when the aspirator burner 43 is stopped, and the fuel supply is shut off, the operation of the fuel evaporation mechanism 31 on the downstream side is continued for a predetermined short time, and the fuel evaporation mechanism 31 is stopped. It is desirable to completely gasify the liquid fuel therein, supply it to the aspirator burner 43 and burn it, so that no fuel or its gas remains between the fuel evaporation mechanism 31 and the aspirator burner 43.
[0055]
Thus, in the present invention, since the mechanism of the aspirator 18 capable of introducing the exhaust gas or the air flow into the ejection portions of the aspirator burners 6, 43 is used, the aspirator burners 6, 43 and the ignition plug 8 are provided in the exhaust pipe 1. To regenerate the filter 2 by burning fuel or fuel gas.
The reducing section 14 of the aspirator 18 can always maintain a negative pressure state if there is a fluid flow, and there is no possibility that fuel remains in the aspirator burners 6 and 43, and the degree of the negative pressure is controlled. Thus, the outputs of the aspirator burners 6 and 43 can be adjusted.
[0056]
The filter regeneration device 3 (FIG. 1) according to the first embodiment and the filter regeneration device 30 (FIG. 4) according to the second embodiment are of a switching regeneration type. May be a continuous regeneration system that performs regeneration at the same time during operation by the engine.
For example, if the bypass pipe 5 is not branched from the exhaust pipe 1 and is attached to the exhaust pipe 1 as it is, the exhaust gas is guided into the aspirator 18 of the aspirator burners 6, 43, and the engine is operated in the same manner as described above. Playback can be performed simultaneously and played back continuously.
[0057]
Alternatively, the exhaust pipe 1 and the filter 2 may be provided in two lines, and the filter regenerators 3 and 30 may be provided in each of the exhaust pipes 1 to alternately perform the operation and the regeneration.
[0058]
Alternatively, a filter regeneration device 3 from one exhaust pipe 1 side to the other exhaust pipe 1 side, which is provided with two exhaust pipes 1 and filters 2 and operates an engine to flow exhaust gas to collect PM, It is also possible to introduce exhaust gas into 30 and atomize the fuel by the aspirator burners 6 and 43.
[0059]
【The invention's effect】
As described above, according to the present invention, since the aspirator mechanism for introducing the exhaust gas or the airflow to the ejection portion of the filter regeneration burner is employed, the good fuel spray is also supplied to the exhaust pipe which is always in a high temperature state. Atomization is promoted, the combustion of the aspirator burner is stabilized, the regeneration time of the filter is shortened, the fuel consumption can be reduced, and the filter can be downsized. It can be.
Further, the output of the aspirator burner automatically changes according to the flow rate of the exhaust gas in the exhaust pipe, so that the output of the aspirator burner can be easily adjusted. If the output of the aspirator burner is large, the filter will burn out, and if it is small, the PM will not burn. However, in the present invention, it is possible to respond flexibly and reduce fuel consumption. If further adjustment of the output of the aspirator burner is necessary, the output can be adjusted by changing the oil pressure of the fuel supplied from the fuel supply pipe 7. However, control by a solenoid valve may be sufficient.
Also, even when the aspirator burner is stopped, the fuel ejecting portion from the fuel supply pipe is maintained in a negative pressure state, so that the fuel present in the metering orifice is discharged from the solenoid valve, and there is a concern that carbon or the like may accumulate. And reliability is improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a state in which a filter regeneration device 3 according to a first embodiment of the present invention is attached to an exhaust pipe 1 of a diesel engine.
FIG. 2 is an enlarged sectional view of the aspirator burner 6;
FIG. 3 is a schematic view of a fuel supply mechanism 20 that supplies fuel to a fuel supply pipe 7;
FIG. 4 is a schematic diagram of a filter regeneration device 30 and a fuel supply mechanism 20 according to a second embodiment of the present invention.
FIG. 5 is a cross-sectional view of the same fuel evaporation mechanism 31.
FIG. 6 is a side view of the fuel evaporation mechanism 31 as viewed from the rear in the traveling direction of the vehicle equipped with the engine.
FIG. 7 is a graph showing the relationship between the temperature of the heating glow plug 33 and the resistance ratio.
FIG. 8 is an enlarged sectional view of the aspirator burner 43;
[Explanation of symbols]
1 Diesel engine exhaust pipe
2 Filter
3. Filter regeneration device (first embodiment, FIG. 1)
4 Switching valve
5 Bypass pipe
6. Aspirator burner (light oil burner, Fig. 2)
7 Fuel supply pipe
8 Ignition plug
9 Connecting pipe part of bypass pipe 5
10 Aspirator body
11 Support stay
12 Contraction member
13 Collision plate
14 Reduction part
15 Negative pressure chamber (mixing chamber)
16 Enlargement
17 Metering orifice
18 Aspirator (aspirator)
19 Heat-resistant wire
20 Fuel supply mechanism (Fig. 3)
21 Fuel tank
22 Fuel pump
23 Pressure Regulator
24 Solenoid valve for fuel supply on / off
30 Filter regeneration device (second embodiment, FIG. 4)
31 Fuel evaporation mechanism (Fig. 5)
32 Evaporation mechanism housing
33 Lower, middle and upper heating glow plugs
34 Lower, middle and upper wicks
35 Fuel introduction section
36 Metering orifice
37 Fuel derivation section
38 Lower, middle and upper plug housings
39 Lower, middle and upper communication paths
40 connection terminal of heating glow plug 33
41 Threaded part of heating glow plug 33
42 Heating part (sheath part) of heating glow plug 33
43 Aspirator burner (light oil evaporation burner, Fig. 8)
44 Open window

Claims (6)

A filter regeneration device in an internal combustion engine that regenerates a filter for purifying exhaust gas of the internal combustion engine,
A bypass pipe provided in an exhaust pipe of the exhaust gas,
Aspirator burner attached to this bypass pipe,
A fuel supply pipe opening to the aspirator burner,
An ignition plug for igniting fuel supplied from the fuel supply pipe to the aspirator burner;
A filter regeneration device for an internal combustion engine, comprising: The aspirator burner,
A contraction section that contracts from the exhaust pipe;
A negative pressure chamber facing this reduction section,
2. A filter regeneration device for an internal combustion engine according to claim 1, further comprising a metering orifice capable of supplying said fuel from said fuel supply pipe facing said negative pressure chamber. 2. A filter regeneration device for an internal combustion engine according to claim 1, wherein a switching valve for changing a flow passage area of said exhaust pipe is provided upstream of said aspirator burner. 2. The filter regeneration device for an internal combustion engine according to claim 1, wherein the bypass pipe is opened upstream of a switching valve that changes a flow passage area of the exhaust pipe. 2. The filter regeneration device for an internal combustion engine according to claim 1, wherein the fuel supply pipe is capable of supplying the fuel vapor gas. The filter regeneration device for an internal combustion engine according to claim 1, wherein the fuel evaporation mechanism is provided between the fuel tank for the fuel and the fuel supply pipe.

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