JP2011220301A - Exhaust device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a rise of cost when suitably supplying fuel to both a catalyst converter and an ignition device, in a constitution configured such that the fuel is supplied to the catalyst converter and the ignition device from a common fuel adding valve which is arranged at an exhaust passage.SOLUTION: The fuel adding valve 7 and a variable fuel pressure regulator 8 are controlled in order to selectively supply fuel to the pre-treatment catalyst converter 8 and a glow plug 21, and first injection by first fuel pressure P1 and second injection by second fuel pressure P2 which is lower than the first fuel pressure P1 are performed. Movable collision boards 50 include springs 50d, and the movable collision boards 50 are displaced to mutually different positions by the first and second injection against elastic forces of the springs 50.

Description

  The present invention relates to an exhaust device capable of supplying fuel to an exhaust passage of an internal combustion engine.

  For the purpose of purifying exhaust gas, an exhaust device that supplies fuel to an exhaust passage of an internal combustion engine is widely used.

  In the apparatus disclosed in Patent Document 1, ignition means such as a glow plug is disposed at a position where fuel from a fuel addition valve provided in an exhaust passage directly contacts, and a catalyst is provided downstream of these fuel addition valve and glow plug. A converter is arranged. The fuel is ignited by the ignition means, and the catalytic converter is heated by the flame.

JP 2006-112401 A

  However, the apparatus of Patent Document 1 cannot change the ratio of the amount of fuel supplied to the ignition means and the amount of fuel supplied directly to the catalytic converter without going through the ignition means. However, it is necessary to provide a fuel addition valve for supplying to the ignition means and a fuel addition valve for supplying to the catalytic converter, which may increase the cost.

  An object of the present invention is to suppress an increase in cost when fuel is suitably supplied to a catalytic converter and an ignition device from a common fuel addition valve disposed in an exhaust passage. And

The first aspect of the present invention is:
A catalytic converter disposed in the exhaust passage of the internal combustion engine;
A fuel addition valve that is disposed upstream of the catalytic converter and supplies fuel into the exhaust passage;
An ignition device capable of igniting the fuel supplied from the fuel addition valve;
A movable collision member for causing the fuel supplied from the fuel addition valve to collide and guiding it to an ignition part of the ignition device, the movable collision member having an elastic body;
A pressure adjusting device for adjusting the pressure of the fuel supplied to the fuel addition valve;
A controller for controlling the fuel addition valve and the pressure adjusting device,
The controller controls the fuel addition valve and the pressure regulator to selectively supply fuel to the catalytic converter and the ignition device, and a first injection by a first fuel pressure; Second injection by a second fuel pressure smaller than the first fuel pressure is executed, and the movable collision member is different from each other against the elastic force of the elastic body by the first and second injections. An exhaust device for an internal combustion engine, wherein the exhaust device is displaced to a position.

  In this aspect, the controller controls the fuel addition valve and the pressure regulator to selectively supply fuel to the catalytic converter and the ignition device, and the first injection by the first fuel pressure is performed. And a second injection with a second fuel pressure smaller than the fuel pressure of 1. The movable collision member includes an elastic body, and the movable collision member is displaced to different positions against the elastic force of the elastic body by the first and second injections. Therefore, in the configuration in which the fuel is supplied to the catalytic converter and the ignition device, it is not necessary to provide a separate fuel addition valve in order to suitably supply the fuel to both, and an increase in cost can be suppressed.

  According to the present invention, in the configuration in which fuel is supplied to the catalytic converter and the ignition device, an increase in cost can be suppressed when fuel is preferably supplied to both.

It is a conceptual diagram of embodiment of this invention. It is a principal part enlarged view which shows a burner apparatus. It is sectional drawing which looked at the burner apparatus in the axial direction. It is sectional drawing which shows a variable fuel pressure regulator. It is a flowchart which shows a fuel supply process.

  Preferred embodiments of the present invention will be described in detail below. However, it should be noted that the embodiments of the present invention are not limited to the following embodiments, and the present invention includes all modifications and applications included in the concept of the present invention defined by the claims. I must. The dimensions, materials, shapes, relative arrangements, and the like of the constituent elements described in the embodiments are not intended to limit the technical scope of the invention only to those unless otherwise specified.

  FIG. 1 shows a schematic configuration of an engine body 1 and its intake and exhaust system in the embodiment. The engine body 1 is an on-vehicle four-cycle diesel engine. An intake pipe 2 and an exhaust pipe 3 (exhaust passage) are connected to the engine body 1. An air flow meter 4 that outputs a signal corresponding to the flow rate of the intake air flowing through the intake pipe 2 is provided in the middle of the intake pipe 2. The air flow meter 4 measures the amount of intake air into the engine body 1. The engine body 1 has a plurality of cylinders, and each cylinder is provided with an in-cylinder fuel injection valve 9. However, only a single in-cylinder fuel injection valve 9 is shown in FIG.

The end of the exhaust pipe 3 is connected to a silencer (not shown), and is opened to the atmosphere at the outlet of the silencer. In the middle of the exhaust pipe 3, the oxidation catalytic converter 6 and the NOx catalytic converter 26 are arranged in series in this order. The oxidation catalytic converter 6 reacts unburned components such as HC and CO with O ₂ to make CO, CO ₂ , H ₂ O and the like. As the catalyst material, for example, Pt / CeO ₂ , Mn / CeO ₂ , Fe / CeO ₂ , Ni / CeO ₂ , Cu / CeO ₂ or the like can be used. The NOx catalytic converter 26 preferably comprises an NOx storage reduction (NSR) converter. The NOx catalytic converter 26 occludes NOx in the exhaust when the oxygen concentration of the inflowing exhaust gas is high, and occludes when the oxygen concentration of the inflowing exhaust gas decreases and a reducing component (for example, fuel) exists. It has a function of reducing NOx. The NOx catalytic converter 26 is configured such that a noble metal such as platinum Pt as a catalyst component and a NOx absorption component are supported on the surface of a base material made of an oxide such as alumina Al ₂ O ₃ . The NOx absorbing component is at least one selected from, for example, an alkali metal such as potassium K, sodium Na, lithium Li, and cesium Cs, an alkaline earth such as barium Ba and calcium Ca, and a rare earth such as lanthanum La and yttrium Y. It consists of one. The NOx catalytic converter 26 may be a selective reduction type NOx catalytic converter (SCR: Selective Catalytic Reduction).

  A fuel addition valve 7, a pretreatment catalytic converter 8, and a glow plug 21 are disposed upstream of the oxidation catalytic converter 6 in the exhaust pipe 3. These fuel addition valve 7, pretreatment catalytic converter 8, and glow plug 21 constitute a burner device 30. The burner device 30 is disposed on the downstream side of a collecting portion of an exhaust manifold (not shown) connected to the engine body 1. The fuel addition valve 7 can add liquid fuel (light oil) into the exhaust.

  The fuel tank 11 is connected to the fuel addition valve 7 via a fuel suction pipe 12, a low pressure fuel pump 13, a high pressure fuel pump 14, a fuel supply pipe 15 and a variable fuel pressure regulator 16. The fuel pumps 13, 14 suck the fuel stored in the fuel tank 11 through the fuel suction pipe 12 and discharge it to the fuel supply pipe 15, whereby the fuel is supplied to the fuel addition valve 7. A high pressure fuel pump 28 is provided in the pipe 27 to the cylinder fuel injection valve 9 installed in the engine body 1. Although details are not shown, the piping 27 branches toward the in-cylinder fuel injection valves 9 corresponding to the number of cylinders. The fuel pumps 13, 14, and 28 are, for example, mechanical, and operate using a driving force of an output shaft (crankshaft) (not shown) of the engine body 1. At least one of the fuel pumps 13, 14, and 28 may be an electric type.

  The variable fuel pressure regulator 16 adjusts the pressure of fuel discharged from the high-pressure fuel pump 14. As shown in FIG. 4, the variable fuel pressure regulator 16 includes a needle valve 17. The needle valve 17 includes a valve seat 17b having an orifice 17a that opens to a branch passage 18 branched from the fuel supply pipe 15, and a needle 17c that opens and closes the orifice 17a while being in contact with the valve seat 17b. Yes. The variable fuel pressure regulator 16 further includes a magnetic armature (not shown) that is integrally connected to the needle valve 17, a spring (not shown) that biases the armature downward (in the direction of closing the needle valve 17), and a magnetic armature (not shown). And a coil 19 for generating magnetic flux in a magnetic circuit composed of a core.

  Based on the required fuel pressure, the magnitude of the current to be supplied to the coil 19 is controlled, and when the magnetic flux in the magnetic circuit composed of the magnetic core and the armature is changed, the force for biasing the armature downward is controlled. Thus, the biasing force of the spring is assisted, and the opening degree of the needle valve 17 is adjusted.

  When the coil 19 is not energized, the needle valve 17 is most open, and in the vicinity thereof, the fuel pressure becomes the second pressure P2 (for example, 5 MPa). When the current supplied to the coil 19 is gradually increased, the needle valve 17 is gradually closed and the fuel pressure is increased. When the supply current is in the vicinity of the maximum value, the discharged fuel is controlled to the first pressure P1 (for example, 10 MPa). The fuel pressure regulator may be of another configuration, for example, a type in which the spring pressure of the spring is set to a value corresponding to the maximum fuel pressure and the fuel pressure is adjusted by urging the armature upward with the coil 19 and compressing it. Good.

  In FIG. 2, the fuel addition valve 7 has a single injection hole 7 a, and the injection hole shaft 7 b of the injection hole 7 a includes a component in a direction transverse to the exhaust pipe 3, and is downstream of the exhaust pipe 3. Inclined towards. There may be a plurality of nozzle holes.

  A pretreatment catalytic converter 8 for reforming the fuel injected from the fuel addition valve 7 is provided in a portion of the exhaust pipe 3 between the fuel addition valve 7 and the oxidation catalytic converter 6. The pretreatment catalytic converter 8 can be configured as an oxidation catalytic converter in which rhodium or the like is supported on a zeolite carrier, for example.

  When the fuel is supplied to the pretreatment catalytic converter 8, if the pretreatment catalytic converter 8 is activated at that time, the fuel is oxidized in the pretreatment catalytic converter 8. The temperature of the processing catalytic converter 8 is raised. Further, when the temperature of the pretreatment catalytic converter 8 is increased, hydrocarbons having a large number of carbon atoms in the fuel are decomposed to generate hydrocarbons having a small number of carbon atoms and high reactivity, whereby the fuel is a highly reactive fuel. To be modified. In other words, the pretreatment catalytic converter 8 constitutes a rapid heat generator that rapidly generates heat on the one hand, and a reformed fuel discharger that discharges the reformed fuel on the other hand. Further, part or all of the fuel supplied from the fuel addition valve 7 is heated or ignited by the glow plug 21, thereby promoting the temperature increase of the exhaust gas.

  The outer diameter of the pretreatment catalytic converter 8 is smaller than the inner diameter of the exhaust pipe 3, and when the pretreatment catalytic converter 8 is accommodated in the exhaust pipe 3, the outer peripheral surface of the pretreatment catalytic converter 8 and the inner peripheral surface of the exhaust pipe 3. Exhaust gas can pass through the catalyst bypass route, which is a gap between The pretreatment catalytic converter 8 is a so-called straight flow type in which individual cells communicate from upstream to downstream. The pretreatment catalytic converter 8 is disposed in a substantially cylindrical outer frame 8a, and the outer frame 8a is supported in the exhaust pipe 3 by a plurality of stays 8b disposed in a generally radial manner. The pretreatment catalytic converter 8 is surrounded by a catalyst detour around substantially the entire circumference except for the stay 8b.

  As shown in FIGS. 2 and 3, the exhaust pipe 3 is formed in a substantially cylindrical shape. The axis of the pretreatment catalytic converter 8 in the exhaust flow direction is deflected downward in the figure from the axis of the exhaust pipe 3 in the exhaust flow direction. For this reason, the catalyst bypass described above is a wide-side bypass 3b on the upper side in the drawing and a narrow-side bypass 3c on the lower side.

  The glow plug 21 is disposed downstream of the fuel addition valve 7 and upstream of the pretreatment catalytic converter 8. The glow plug 21 is connected to the in-vehicle DC power source 23 via the booster circuit 22 and can ignite the fuel supplied from the fuel addition valve 7 by heat generated when energized. The glow plug 21 has an axis that is inclined toward the upstream side of the exhaust pipe 3. Can be arranged. In addition, as an ignition means, other apparatuses, such as a ceramic heater and a spark plug, especially an electrothermal type or a spark ignition type apparatus can be used.

  A lower portion of the front end portion of the outer frame 8a that houses the pretreatment catalytic converter 8 is a bowl-shaped protruding portion 8b that protrudes toward the upstream side. A substantially flat fixed collision plate 20 is fixed to the protruding portion 8b. The fixed collision plate 20 is disposed at a position deflected downward in the exhaust pipe 3 and is slightly inclined toward the downstream side.

  A movable collision plate 50 is disposed at a position deflected upward in the exhaust pipe 3. The movable collision plate 50 includes a horizontal portion 50a that is substantially horizontal when there is no load, a skewed portion 50b formed at an end portion on the upstream side, and a shaft portion 50c fixed to the rear end portion of the skewed portion 50b. And a spring 50d fixed to the lower surface of the skew portion 50b. The spring 50d is a compression coil spring. The shaft portion 50c is rotatably supported in the exhaust pipe 3. The horizontal portion 50a of the movable collision plate 50 intersects the nozzle hole shaft 7b of the fuel addition valve 7 when the spring 50d is not loaded.

  The fixed collision plate 20 and the movable collision plate 50 can be formed of a material excellent in heat resistance and impact resistance such as SUS. The fuel addition valve 7 injects the fuel obliquely downward toward the collision plates 20 and 50. The trajectory of the fuel supplied from the fuel addition valve 7 includes a component in a direction crossing the exhaust pipe 3. The collision plates 20 and 50 promote the atomization and atomization of the fuel when the fuel collides, and improve the dispersibility and diffusibility. The fuel that has collided with the collision plates 20 and 50 is deflected downstream by the exhaust flow. The fuel that has collided with the stationary collision plate 20 is mainly supplied to the pretreatment catalytic converter 8. The fuel that has collided with the movable collision plate 50 is mainly supplied to the heat generating portion 21 a of the glow plug 21.

  As shown in FIGS. 2 and 3, the crossing direction of the exhaust pipe 3 between the collision point 50 e of the movable collision plate 50 where the fuel supplied from the fuel addition valve 7 collides and the injection hole 7 a of the fuel addition valve 7 is increased. The distance d2 is smaller than the distance d1 in the transverse direction of the exhaust pipe 3 between the collision point 20a of the fixed collision plate 20 where the fuel supplied from the fuel addition valve 7 collides and the injection hole 7a of the fuel addition valve 7. In other words, the collision point 50e of the movable collision plate 50 and the collision point 20a of the fixed collision plate 20 are arranged at different positions in the width direction (that is, the transverse direction) of the exhaust pipe 3.

  When the fuel pressure is set to the first pressure P1 by the variable fuel pressure regulator 16 described above, the fuel injected from the fuel addition valve 7 resists the elastic force of the spring 50d against the movable collision plate 50 by a two-dot chain line in FIG. It is pushed down in the direction indicated by the arrow a (clockwise) to the position shown to be in a retracted state in which it is retracted from the fuel trajectory and collides with the collision point 20a of the fixed collision plate 20. As a result, the fuel is mainly supplied to the pretreatment catalytic converter 8. On the other hand, when the fuel pressure is set to the second pressure P2 lower than the first pressure, the injected fuel collides with the movable collision plate 50, but only pushes the movable collision plate 50 slightly, and the development interferes with the fuel trajectory. State is maintained. Therefore, the fuel is supplied mainly to the glow plug 21 and its vicinity without reaching the fixed collision plate 20.

  The glow plug 21 is disposed in the vicinity of the pretreatment catalytic converter 8 and slightly upstream of the front end face of the pretreatment catalytic converter 8, thereby enabling heat exchange with the pretreatment catalytic converter 8. That is, when the temperature of the pretreatment catalytic converter 8 is increased, the glow plug 21 is heated in the vicinity of the heat generating portion 21a due to its thermal radiation and convection, so that ignition of the fuel supplied from the fuel addition valve 7 is promoted. It is arranged in the position. For this purpose, a gap 31 is provided between the downstream end of the movable collision plate 50 and the pretreatment catalytic converter 8, and the radiant heat from the pretreatment catalytic converter 8 is blocked by the movable collision plate 50. It is made to act on the vicinity including the heat generating part 21a of the glow plug 21 without. However, the position of the glow plug 21 in the flow direction may be the same as the front end face of the pretreatment catalytic converter 8 or may be downstream of this.

  The engine body 1 is provided with an ECU 10 that is an electronic control unit for controlling the driving state in accordance with the operating conditions of the engine body 1 and the driver's request. The ECU 10 includes a CPU that executes various arithmetic processes related to the control of the engine body 1, a ROM that stores programs and data necessary for the control, a RAM that temporarily stores arithmetic results of the CPU, and the like. An input / output port for inputting / outputting signals is provided.

  In addition to the air flow meter 4, the ECU 10 includes a crank position sensor 24 that detects the crank angle of the engine body 1, an accelerator opening sensor 25 that outputs an electric signal corresponding to the accelerator opening, and exhaust gas downstream of the NOx catalytic converter 26. A NOx sensor 32 arranged in the passage, a water temperature sensor 33 for detecting the engine cooling water temperature, a SOx sensor 34 made of a solid electrolyte provided near the inlet of the NOx catalytic converter 26, and a drive wheel (not shown) are arranged in the vicinity. Various sensors including a vehicle speed sensor 35 for detecting the vehicle speed are connected via electric wiring, and these output signals are input to the ECU 10. Various types of actuators including a fuel addition valve 7, an in-cylinder fuel injection valve 9, and a variable fuel pressure regulator 18 are connected to the ECU 10 through electric wiring, and these are controlled by the ECU 10. The ECU 10 can detect the engine speed based on the output value of the crank position sensor 24 and can detect the required load of the engine body 1 based on the output value of the accelerator opening sensor 25.

  In the present embodiment, the ECU 10 performs the temperature raising process by the ignition of fuel, the PM oxidation process for the pretreatment catalytic converter 8 and the oxidation catalytic converter 6, the NOx reduction process for the NOx catalytic converter 26, and the SOx poisoning recovery process. The fuel addition valve 7 is controlled to inject fuel into the exhaust, and this fuel is supplied to the pretreatment catalytic converter 8, the oxidation catalytic converter 6, and the NOx catalytic converter 26. Among these, the temperature raising process by the ignition of fuel is performed in a deployed state in which the movable collision plate 50 is deployed, and most of the supplied fuel is ignited by the glow plug 21. All other processes are performed in a retracted state in which the movable collision plate 50 is retracted, and most of the supplied fuel is supplied to the pretreatment catalytic converter 8.

  The amount of fuel injected into the fuel addition valve 7 can be set for each control such as the ignition temperature raising process, the PM oxidation process, the NOx reduction process, the SOx poisoning recovery process, and the PM regeneration process described above. . In the ROM of the ECU 10, a target total injection amount calculation map for calculating a target total injection amount suitable for the operating state of the engine body 1 includes the above processing types (ignition temperature raising process, oxidation process, NOx reduction process, SOx poisoning recovery process, PM regeneration process, etc.). When performing the fuel injection control, the ECU 10 detects the engine speed, the accelerator opening, and the intake air amount, and uses these as parameters to access the target total injection amount calculation map to calculate the target total injection amount. The ECU 10 calculates the valve opening time so that the target total injection amount of fuel is injected from the fuel addition valve 7. Then, the ECU 10 issues a command to the fuel addition valve 7 (specifically, a drive mechanism (not shown) that drives the fuel addition valve 7 to open and close) to open the fuel addition valve 7 and the calculated valve opening time. The valve is closed when has elapsed.

  In the present embodiment configured as described above, the ECU 10 controls the fuel addition valve 7 and the variable fuel pressure regulator 18 so that the warming-up of the oxidation catalytic converter 6 and the NOx catalytic converter 26 is not completed. With the collision plate 50 in a deployed state, fuel injection accompanied by ignition is executed (cold glow ignition).

  In FIG. 5, first, the ECU 10 reads the values of parameters related to the state of the pretreatment catalytic converter 6 and the driving state of the vehicle (S10). The parameters read here are the engine speed detected by the crank position sensor 24, the required load detected by the accelerator opening sensor 25, the fuel injection amount from the in-cylinder fuel injection valve 9 set separately by the ECU 10, The coolant temperature detected by the water temperature sensor 32, the NOx amount downstream of the catalyst detected by the NOx sensor 32, and the SOx concentration detected by the SOx sensor 34 are included.

  Next, the ECU 10 determines whether a predetermined fuel supply condition is satisfied (S20). The fuel supply condition is, for example, that both a catalyst request based on the state of the catalytic converters 6 and 26 and an operation state request based on the driving state of the vehicle are satisfied. The catalyst requirements are, for example, “the estimated temperature of at least one of the catalytic converters 6 and 26 is lower than a predetermined value”, “the NOx occlusion amount of the NOx catalytic converter 26 is larger than a predetermined value”, “NOx purification of the NOx catalytic converter 26” This is established when either “the amount is greater than a predetermined value” or “the SOx (sulfur oxide) deposition amount of the NOx catalytic converter 26 is greater than a reference value” is established. The driving state request is, for example, “the vehicle speed is being decelerated”. If the fuel supply condition is not satisfied, the processing after step S30 is skipped, and the processing is returned.

  The estimated temperature of the catalytic converters 6 and 26 can be calculated by a predetermined function or map based on, for example, the exhaust gas temperature, the cooling water temperature, and the intake air temperature. The NOx occlusion amount of the NOx catalytic converter 26 is, for example, a predetermined function or map as an integrated value from the execution of the previous reduction process of the NOx amount discharged from the in-cylinder fuel injection valve 9 and the engine speed. Can be calculated. The NOx purification amount of the NOx catalytic converter 26 is a value indicating the NOx purification capacity of the catalyst material, and is obtained, for example, by subtracting the NOx amount downstream of the catalyst from the estimated NOx emission amount from the engine body 1. The estimated NOx emission amount is estimated based on the engine operating state, that is, the engine rotation speed and the fuel injection amount from the in-cylinder fuel injection valve 9 (the accelerator opening or the throttle opening may be used instead). The NOx amount downstream of the catalyst is detected by the NOx sensor 32. The SOx accumulation amount of the NOx catalytic converter 26 is calculated as, for example, an integrated value after the previous processing of the sulfur concentration in the fuel and the fuel consumption amount in the engine body 1. The detected value of the SOx sensor 34 can be used as the sulfur concentration in the fuel, but a fixed value or a known value provided from a gas station or a fuel dealer may be used.

  If the determination in step S20 is affirmative, that is, if the fuel supply condition is satisfied, the ECU 10 next determines whether the warming-up of the oxidation catalytic converter 8 and the NOx catalytic converter 26 has been completed (S30). This determination is made by comparing the estimated temperature of the oxidation catalytic converter 6 as a value representing the warm-up state of the catalytic converters 6 and 26 with a predetermined reference value, and when the estimated temperature exceeds the reference value. Affirmed. The estimated temperature of the oxidation catalytic converter 6 can be obtained by a predetermined function or map based on, for example, the engine water temperature detected by the water temperature sensor 33, and is detected by installing a dedicated temperature sensor in the oxidation catalytic converter 6. Also good.

  When the determination in step S30 is affirmative, that is, when the warming-up of the oxidation catalytic converter 6 and the NOx catalytic converter 26 has been completed, the ECU 10 controls the variable fuel pressure regulator 18 to set the fuel pressure to the first pressure P1, Then, fuel is injected (S50). As a result, the movable collision plate 50 is retracted against the elastic force of the spring 50d by the pressure of the fuel, and almost the entire amount of the fuel collides with the fixed collision plate 20 and then flows into the pretreatment catalytic converter 8 by the exhaust flow. The target processing is executed among the PM oxidation processing for the pretreatment catalytic converter 8 and the oxidation catalytic converter 6, the NOx reduction processing for the NOx catalytic converter 26, and the SOx poisoning recovery processing.

  If NO in step S30, that is, if the warm-up of the catalytic converters 6 and 26 has not yet been completed, the ECU 10 controls the variable fuel pressure regulator 18 to set the fuel pressure to the second pressure P2, and in that state the fuel is supplied. Inject (S40). As a result, the movable collision plate 50 is brought into a developed state by the elastic force of the spring 50d, and almost the entire amount of fuel collides with the movable collision plate 50. The reflected or attached fuel is supplied to the vicinity including the glow plug 21 by the exhaust flow and ignited. As a result, the oxidation catalytic converter 6 and the NOx catalytic converter 26 can be rapidly heated. The process exits this routine on the condition that the injection has ended.

  As described above, in the present embodiment, the ECU 10 controls the fuel addition valve 7 and the variable fuel pressure regulator 8 in order to selectively supply fuel to the pretreatment catalytic converter 8 and the glow plug 21, so that the first The first injection with the fuel pressure P1 and the second injection with the second fuel pressure P2 smaller than the first fuel pressure P1 are executed. The movable collision plate 50 includes a spring 50d, and the movable collision plate 50 is displaced to different positions against the elastic force of the spring 50d by the first and second injections. Therefore, in the configuration in which the fuel is supplied to the pretreatment catalytic converter 8 and the glow plug 21, it is not necessary to provide individual fuel addition valves for suitably supplying the fuel to both, and an increase in cost can be suppressed. .

  In the present embodiment, the movable collision plate 50, which is a structure for switching the fuel supply destination, is a simple mechanism using the spring 50d. Therefore, it does not require external power supply and the exhaust pipe tends to be hot. Therefore, it is not necessary to provide a complicated drive mechanism, and the risk of failure can be suppressed.

  Although the invention has been described with a certain degree of particularity, it should be understood that various modifications and changes can be made without departing from the spirit and scope of the claimed invention. Embodiments of the present invention are not limited to the above-described embodiments, and the present invention includes all modifications and applications included in the concept of the present invention defined by the claims. Therefore, the present invention should not be construed as being limited, and can be applied to any other technique belonging to the scope of the idea of the present invention. The means for solving the problems in the present invention can be used in combination as much as possible.

  For example, although the spring 50d included in the movable collision plate 50 is a compression coil spring, other types of springs such as a tension spring, a plate spring, a spring, and a torsion spring, or other types of elastic bodies may be employed. Further, the movable collision member itself may be made of a leaf spring or other flexible material.

  Further, in this embodiment, the fuel pressures P1 and P2 are fixed values, respectively, but the variable fuel pressure regulator 16 and other pressure regulators may be controlled so that the fuel pressures P1 and P2 increase as the exhaust speed increases. The exhaust speed in this case can be estimated based on the intake air amount, for example. In this case, it is possible to supply fuel in an appropriate trajectory even when the exhaust speed changes. The fuel pressure may be controlled by changing the discharge pressure of the high-pressure pump 14, and in this case, a variable fuel pressure regulator can be dispensed with.

  Also, conditions other than those described above can be selected for selecting the first and second fuel pressures. Further, a plurality of injections may be intermittently performed by any combination of fuel pressures depending on the purpose of supplying fuel. The ECU 10 may control the variable fuel pressure regulator 16 to cause the fuel addition valve 7 to execute a single injection while continuously changing the fuel pressure.

  In addition, the arrangement method and shape of each collision plate can be changed as appropriate within a range having a function of atomizing the fuel injected from the fuel addition valve 7 and a function of guiding the fuel to the pretreatment catalytic converter 8. it can. Each collision plate may be provided with an arbitrary number of through holes, concave portions and / or convex portions. The vertical cross section and / or the horizontal cross section of the collision plate may be other shapes such as an arc shape instead of a straight shape. A configuration without a fixed collision plate can also be employed. In this case, the fuel from the fuel addition valve 7 may collide with the tube wall of the exhaust pipe 3.

  At least one of the pretreatment catalytic converter and the exhaust pipe may have a non-circular cross section such as an ellipse or an oval cross section. The interval in the transverse direction of the exhaust pipe 3 may be such that the pretreatment catalytic converter 8 is closer to the fuel addition valve 7 than the heat generating portion of the glow plug 21 (ignition device). The cross section of the pretreatment catalytic converter 8 in the transverse direction of the exhaust pipe 3 may extend over the entire interior of the exhaust pipe 3. The type and order of other exhaust treatment apparatuses existing downstream of the pretreatment catalytic converter 8 are also arbitrary.

1 Engine Body 3 Exhaust Pipe 6 Oxidation Catalytic Converter 7 Fuel Addition Valve 8 Pretreatment Catalytic Converter 9 In-Cylinder Fuel Injection Valve 10 ECU
16 Variable fuel pressure regulator 20 Fixed collision plate 21 Glow plug 21a Heat generating part 26 NOx catalytic converter 30 Burner device 50 Movable collision plate 50d Spring

Claims (1)

A catalytic converter disposed in the exhaust passage of the internal combustion engine;
A fuel addition valve that is disposed upstream of the catalytic converter and supplies fuel into the exhaust passage;
An ignition device capable of igniting the fuel supplied from the fuel addition valve;
A movable collision member for causing the fuel supplied from the fuel addition valve to collide and guiding it to an ignition part of the ignition device, the movable collision member having an elastic body;
A pressure adjusting device for adjusting the pressure of the fuel supplied to the fuel addition valve;
A controller for controlling the fuel addition valve and the pressure adjusting device,
The controller controls the fuel addition valve and the pressure regulator to selectively supply fuel to the catalytic converter and the ignition device, and a first injection by a first fuel pressure; Second injection by a second fuel pressure smaller than the first fuel pressure is executed, and the movable collision member is different from each other against the elastic force of the elastic body by the first and second injections. An exhaust apparatus for an internal combustion engine, wherein the exhaust apparatus is displaced to a position.

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