JP4525564B2 - Internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine that supplies reformed gas generated from exhaust gas and fuel added to the exhaust gas to an intake passage.

  Conventionally, fuel is added to exhaust gas, and this is reformed by a reforming catalyst supported on a reformer to generate reformed gas. An internal combustion engine is known in which this reformed gas is supplied to an intake passage and burned in a combustion chamber together with an air-fuel mixture. For example, this type of internal combustion engine is disclosed in the following Patent Document 1, and the added fuel is led to the reforming catalyst of the reformer together with the exhaust gas, while the exhaust gas is sent to the reformer through another path. Thus, the reformed gas is generated by an endothermic reaction due to the exhaust heat of the exhaust gas in this different path.

JP 2004-92520 A

  By the way, the reforming catalyst supported on the reformer can generate a reformed gas by promoting the reforming reaction when the bed temperature becomes equal to or higher than a predetermined activation temperature (for example, 650 ° C.). .

  However, when the engine is cold, such as immediately after the engine is started, the temperature of the exhaust gas discharged from the combustion chamber is low and the reforming catalyst cannot be warmed to the activation temperature. The reformed gas cannot be generated. In addition, during the normal operation after the warm-up operation is completed, the reforming reaction proceeds to lower the bed temperature of the reforming catalyst. Therefore, the exhaust gas exhaust heat at that time activates the reforming catalyst. In some cases, the temperature cannot be maintained above the temperature, and sufficient reformed gas cannot be generated.

  For this reason, the reformed gas cannot be introduced into the combustion chamber in a situation where the bed temperature of such a reforming catalyst does not reach the activation temperature. Can't get.

  Therefore, the present invention improves the disadvantages of the conventional example, and even if the exhaust gas led to the reformer does not reach a temperature that can promote the reforming reaction of the reforming catalyst. It is an object of the present invention to provide an internal combustion engine that can raise the bed temperature of a quality catalyst to an activation temperature or higher.

  In order to achieve the above object, according to the first aspect of the present invention, an exhaust path for exhausting the exhaust gas discharged from each cylinder to the outside, and an exhaust gas diversion path for diverting a part of the exhaust gas flowing through the exhaust path. A first fuel supply device capable of supplying fuel into the exhaust gas diversion path, and a fuel supplied from the first fuel supply apparatus and the exhaust gas in the exhaust gas diversion path are caused to flow to generate reformed gas. A reformer having an exhaust passage through which the exhaust gas from the downstream side of the branch portion of the exhaust gas diversion path in the reforming chamber and the exhaust path to be introduced, and the reformed gas generated by the reformer are introduced into the intake path An air supply device and a second fuel supply device provided downstream of the branch portion of the exhaust gas branching path in the exhaust gas path and upstream of the reformer, and air supply in the exhaust gas path apparatus And a, an oxidation catalyst provided between the beauty second fuel supply device and the reformer.

  According to the first aspect of the present invention, the air and fuel supplied from the air supply device and the second fuel supply device flow into the oxidation catalyst and cause an exothermic reaction, thereby raising the temperature of the surrounding exhaust gas. . Since the exhaust gas whose temperature has risen flows into the exhaust passage of the reformer, the bed temperature of the reforming catalyst of the reformer can be raised to the activation temperature.

  For example, in the invention according to claim 2, in the internal combustion engine according to claim 1, when the bed temperature of the reforming catalyst supported in the reforming chamber of the reformer is lower than a predetermined activation temperature, the air Control means is provided for causing the supply device and the second fuel supply device to supply air and fuel. Accordingly, it is possible to raise the temperature of the reforming catalyst to the activation temperature when the bed temperature is not sufficient for the reforming reaction.

  Here, in the invention according to claim 3, in the internal combustion engine according to claim 2, the bed temperature of the reforming catalyst of the reformer is equal to or higher than a guaranteed durability temperature at which the durability of the reforming catalyst can be guaranteed. The control means is configured to cause the air supply device to supply air when the air supply device has become.

  That is, there is a risk that the bed temperature of the reforming catalyst will rise to a temperature at which damage or the like is a concern, depending on the temperature of the exhaust gas. Can be improved.

  In the internal combustion engine according to the present invention, when the reforming catalyst of the reformer has not reached the activation temperature or when the engine is cold, such as immediately after the engine is started, or when the reforming reaction proceeds, the bed temperature of the reforming catalyst decreases. In this case, the temperature of the exhaust gas can be raised by the exothermic reaction of the oxidation catalyst to which air and fuel are introduced, and the bed temperature of the reforming catalyst can be raised to the activation temperature or higher. Therefore, in this internal combustion engine, even when the exhaust gas does not reach a temperature that can promote the reforming reaction of the reforming catalyst, a sufficient reforming reaction is caused to generate the reformed gas. be able to.

  Embodiments of an internal combustion engine according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited to the embodiments.

  Embodiments of an internal combustion engine according to the present invention will be described.

  First, the configuration of the internal combustion engine in the present embodiment will be described in detail with reference to FIG.

  The internal combustion engine of the present embodiment includes an internal combustion engine main body 1, an intake path 2 for introducing air into the first to fourth cylinders 1a to 1d in the internal combustion engine main body 1, and the first to fourth cylinders 1a to 1d. An exhaust path 3 for discharging the exhaust gas discharged from 1d to the outside and an electronic control unit (hereinafter referred to as “ECU”) 4 for performing combustion control are provided.

  First, the intake passage 2 includes an intake passage 2A for introducing air from the outside, and an intake manifold 2B for diverting and sucking the air in the intake passage 2A to the first to fourth cylinders 1a to 1d. .

  In the intake passage 2A, an air flow meter 5 for measuring the intake air amount, a throttle valve 6 for adjusting the intake amount of air into the first to fourth cylinders 1a to 1d, and a throttle for operating the throttle valve 6 A valve actuator 6a is provided. Here, the measurement signal of the air flow meter 5 is output to the ECU 4, and the ECU 4 calculates the intake air amount and the load. Further, the throttle valve actuator 6 a is controlled in operation by the ECU 4 to adjust the valve opening angle of the throttle valve 6.

  Each branch passage in the intake manifold 2B communicates with each intake port (not shown) from the first to fourth cylinders 1a to 1d formed in the internal combustion engine body 1, and each of them is connected to the intake manifold 2B. The intake port is provided with first to fourth fuel injection devices 9a to 9d that inject fuel from the fuel tank 8 pumped by the fuel pump 7. Here, in the first to fourth fuel injection devices 9a to 9d, the injection amount and the injection timing of each fuel are controlled by the ECU 4. In FIG. 1, for convenience of illustration, first to fourth fuel injection devices 9 a to 9 d are provided in the respective branch passages of the intake manifold 2 </ b> B.

  Subsequently, the exhaust path 3 is provided with an exhaust manifold 3A that collects exhaust gases discharged from the first to fourth cylinders 1a to 1d through respective diversion passages communicating with the exhaust gases. Here, as the exhaust manifold 3A, a so-called 4-1 type of exhaust gas that finally passes through each branch passage and collects in one flow path is exemplified. Therefore, the exhaust passage 3B of the present embodiment is provided with an exhaust passage 3B that guides the exhaust gas collected in the exhaust manifold 3A to the downstream side (that is, the outside side). For example, an A / F (air-fuel ratio) sensor 10 is provided in the exhaust passage 3B, and an output signal of the A / F sensor 10 is used for air-fuel ratio control of the first to fourth cylinders 1a to 1d by the ECU 4. Used.

  Here, in the exhaust path 3 of the present embodiment, the catalyst device 11 that purifies the exhaust gas and the reformer 12 that supports a reforming catalyst (for example, a rhodium type) are downstream of the exhaust passage 3B. Is deployed on the side. In this embodiment, the reformer 12 is arranged upstream of the catalyst device 11 as shown in FIG.

  The reformer 12 of the present embodiment includes a cylinder 12a that allows exhaust gas discharged from the first to fourth cylinders 1a to 1d to flow from the exhaust passage 3B side and to be discharged to the downstream catalytic device 11 side, and A reforming chamber 12b is provided in the cylindrical body 12a and in which a reforming catalyst is supported. In the reforming chamber 12b, an endothermic reaction ( Reforming reaction) occurs to generate reformed gas.

For example, when the exhaust gas is “7.6 CO ₂ + 6.8H ₂ O + 40.8N ₂ ” and the fuel is gasoline fuel “C _7.6 H _13.6 ”, the endothermic reaction is
1.56 (7.6 CO ₂ +6.8 H ₂ O + 40.8 N ₂ ) +3 (C _7.6 H _13.6 ) +984.8 Kcal → 31 H ₂ +34.7 CO + 63.6 N ₂
It is represented by

  That is, according to the endothermic reaction in this case, 31 mol of hydrogen gas and 34.7 mol of carbon monoxide gas are generated from 3 mol of the gasoline fuel.

  Therefore, in this internal combustion engine, it is necessary to introduce exhaust gas and fuel into the reforming chamber 12b in order to perform such reforming reaction by the reformer 12.

  Therefore, first, in the present embodiment, an exhaust gas diversion passage (exhaust gas diversion passage) 13 for diverting a part of the exhaust gas flowing through the exhaust passage 3 and leading it to the reforming chamber 12b is provided. As the exhaust gas diversion passage 13 of the present embodiment, a part of the exhaust gas flowing through the exhaust passage 3B by connecting the exhaust passage 3B located on the upstream side of the reformer 12 and the inlet side of the reforming chamber 12b. An example of dividing the current is illustrated.

  In the present embodiment, the first fuel supply device 14 shown in FIG. 1 for supplying fuel into the exhaust gas branch passage 13 is provided. As a result, the fuel from the fuel tank 8 is supplied into the exhaust gas diversion passage 13, and the fuel is guided to the reforming chamber 12b together with the exhaust gas flowing through the exhaust gas diversion passage 13.

  Here, in the first fuel supply device 14, the fuel injection amount is controlled by the ECU 4 in accordance with the operating state of the internal combustion engine such as the engine speed and the load. That is, the amount of reformed gas required for the internal combustion engine (in other words, the opening angle of the flow rate adjusting valve 16 in the reformed gas introduction passage 15) can be determined according to the operating state of the internal combustion engine. Since the amount of reformed gas produced depends on the amount of fuel injected from the first fuel supply device 14, the amount of fuel injected from the first fuel supply device 14 is determined when the operating state of the internal combustion engine becomes clear. it can. Therefore, in this embodiment, a map showing the amount of fuel injected into the exhaust gas diversion passage 13 corresponding to the operating state of the internal combustion engine is prepared, and the first fuel supply device is provided to the ECU 4 using this map. The fuel injection amount from 14 is set.

  By the way, when the reforming catalyst supported in the reforming chamber 12b becomes lower than a predetermined activation temperature (for example, 650 ° C.), the reforming reaction becomes dull and a reformed gas (hydrogen gas) may be generated. Can not.

  Therefore, the ECU 4 is configured to set the injection amount and the injection timing of the first fuel supply device 14 so that the fuel is not injected from the first fuel supply device 14 or the injection amount is reduced at such a low temperature.

  Further, the reforming chamber 12b of the present embodiment is composed of a plurality of chambers communicating with each other, each of which carries a reforming catalyst, and each chamber is disposed at a predetermined interval in the cylindrical body 12a. To do. Thus, an exhaust passage 12c through which exhaust gas from the exhaust passage 3B side flows is formed between the outer wall surfaces of the rooms. That is, the reformer 12 of this embodiment uses the heat of the high-temperature exhaust gas (in other words, exchanges heat with the heat of the high-temperature exhaust gas) to increase the temperature of the reforming catalyst. Thus, the reforming reaction is activated.

  In this embodiment, a reformed gas introduction path is provided for introducing the reformed gas generated by the reformer 12 into the first to fourth cylinders 1a to 1d. As the reformed gas introduction path of the present embodiment, a reformed gas introduction path 15 is provided for communicating between the outlet side of the reforming chamber 12b and the downstream side of the throttle valve 6 in the intake path 2A.

  The reformed gas introduction passage 15 is provided with a flow rate adjusting valve 16 for adjusting the amount of reformed gas introduced into the intake passage 2A, and a valve actuator 16a for operating the flow rate adjusting valve 16. The valve actuator 16a is operation-controlled by the ECU 4.

  Here, the reformed gas discharged from the reformer 12 or the exhaust gas that has not undergone the reforming reaction is in a high temperature state, and when these are introduced into the intake passage 2A as they are, the air sucked from the outside warms. As a result, the charging efficiency into the first to fourth cylinders 1a to 1d deteriorates.

  In the present embodiment, in order to suppress such deterioration of the charging efficiency, a cooling device 17 is provided in the reformed gas introduction passage 15 as shown in FIG. 1, whereby the reformed gas discharged from the reformer 12 is provided. Or cool the exhaust gas. For example, the cooling device 17 is not limited to one that is ON / OFF controlled by the ECU 4, but may be one that can be variably controlled by the ECU 4.

  Thus, the reformer 12 of the present embodiment is configured to promote the reforming reaction using the heat of the high-temperature exhaust gas. However, when the exhaust gas is at a low temperature, for example, immediately after the engine is started, the bed temperature of the reforming catalyst does not rise to a predetermined activation temperature no matter how the above structure is adopted. The reforming reaction becomes insufficient. Further, even during normal operation after completion of warm-up operation, when the reforming reaction proceeds, the bed temperature of the reforming catalyst may be lower than its activation temperature.

  Therefore, in this embodiment, when the bed temperature of the reforming catalyst does not reach the predetermined activation temperature, the exhaust gas distribution in the exhaust passage 3 is increased in order to quickly raise the bed temperature to the activation temperature. An air supply device 18, a second fuel supply device 19, and an oxidation catalyst 20 are provided downstream of the branch point with the passage 13 and upstream of the reformer 12, and thereby, the exhaust passage 12 c of the reformer 12. Increase the temperature of the exhaust gas flowing into the.

  Specifically, the air supply device 18 and the second fuel supply device 19 are arranged on the downstream side of the branch point of the exhaust gas branching passage 13 in the exhaust passage 3B, and at the downstream end of the exhaust passage 3B. The oxidation catalyst 20 is attached. The oxidation catalyst 20 is attached to the upstream end of the reformer 12 via the exhaust passage 3C at the downstream end. The exhaust passage 3B and the exhaust passage 3C in the exhaust passage 3 are referred to as “first exhaust passage 3B” and “second exhaust passage 3C”, respectively, for convenience. In the present embodiment, the third exhaust passage 3D is interposed between the reformer 12 and the catalyst device 11.

  Accordingly, when air and fuel are supplied from the air supply device 18 and the second fuel supply device 19 to the exhaust passage 3B, the air and fuel cause an exothermic reaction in the oxidation catalyst 20, and the temperature of the surrounding exhaust gas. To raise. For this reason, the exhaust gas whose temperature has risen flows into the exhaust passage 12c of the reformer 12 and raises the bed temperature of the reforming catalyst.

  Here, the air supply device 18 controls the air supply amount and the supply timing by the ECU 4. In the second fuel supply device 19, the fuel injection amount and the injection timing are controlled by the ECU 4. In this embodiment, the reformer 12 is provided with a bed temperature sensor 21 for detecting the bed temperature of the reforming catalyst in order to cause the ECU 4 to execute such control.

  The ECU 4 detects the bed temperature of the reforming catalyst from the bed temperature sensor 21, and if the bed temperature is lower than a predetermined temperature, the ECU 4 respectively controls the air supply device 18 and the second fuel supply device 19. It is configured to supply air and fuel. The predetermined temperature for determining whether or not the supply of air and fuel is necessary is the temperature on the low temperature side in the temperature range in which the reforming reaction of the reforming catalyst can be promoted (hereinafter referred to as “reformable temperature”). Is set. For example, in the present embodiment, the predetermined activation temperature (650 ° C.) described above is set as the reformable temperature.

  By the way, the supply amounts of air and fuel supplied from the air supply device 18 and the second fuel supply device 19 can be determined based on the current bed temperature of the reforming catalyst. That is, when the bed temperature of the reforming catalyst is lower than the reformable temperature, it is necessary to improve the exothermic reaction in the oxidation catalyst 20 by increasing the supply amount of air and fuel as the temperature difference increases. Yes, it is possible to determine the respective supply amounts by clarifying the bed temperature of the current reforming catalyst. For this reason, in this embodiment, a map showing the amount of air and fuel supplied to the first exhaust passage 3B according to the bed temperature of the reforming catalyst is prepared, and this is used to send air to the ECU 4. The supply amounts of air and fuel from the supply device 18 and the second fuel supply device 19 are set.

  On the other hand, if the reforming catalyst of the reformer 12 exceeds a certain temperature, it may not be able to exhibit the desired reforming performance and may be damaged. For example, when the temperature of the exhaust gas is abnormally increased, or when the temperature of the exhaust gas is excessively increased due to the supply of air and fuel from the air supply device 18 and the second fuel supply device 19 described above. The bed temperature of the reforming catalyst may increase significantly.

  Therefore, a durability guarantee temperature (for example, 800 ° C.) of the reforming catalyst that does not cause such inconvenience is set, and when the durability guarantee temperature is exceeded, only the air is supplied from the air supply device 18 and the reforming catalyst is improved. The ECU 4 is configured to cool the quality catalyst. As for the air supply amount at that time, a map showing the air supply amount required for cooling according to the bed temperature of the reforming catalyst is prepared, and this is used by the ECU 4 to set.

  Hereinafter, the control operation of the ECU 4 will be described with reference to the flowchart of FIG.

  First, the ECU 4 of the present embodiment detects the bed temperature of the reforming catalyst of the reformer 12 based on the detection signal of the bed temperature sensor 21, and whether or not the bed temperature is equal to or higher than the reformable temperature described above. (Step ST1).

  Here, when the bed temperature of the reforming catalyst is lower than the reformable temperature, the ECU 4 causes the air from the air supply device 18 and the second fuel supply device 19 according to the bed temperature of the reforming catalyst. The fuel supply amount is read from the above-described map, and the air supply device 18 and the second fuel supply device 19 are instructed to supply air and fuel at the respective supply amounts (step ST2).

  Thereby, the air supply device 18 and the second fuel supply device 19 supply air and fuel to the first exhaust passage 3B, respectively. The air and fuel flow into the oxidation catalyst 20 together with the exhaust gas, causing an exothermic reaction to raise the temperature of the surrounding exhaust gas. Thereafter, the exhaust gas whose temperature has risen flows through the exhaust passage 12c of the reformer 12, and accordingly the bed temperature of the reforming catalyst is raised.

  After the processing of step ST2, the ECU 4 returns to step ST1 to make a comparison between the reforming catalyst bed temperature and the reformable temperature, and the reforming catalyst bed temperature can still be reformed. When the temperature is lower than the temperature, the process proceeds to step ST2 and the same processing is repeated.

  On the other hand, if it is determined in step ST1 that the bed temperature of the reforming catalyst is equal to or higher than the reformable temperature, the ECU 4 determines whether or not the bed temperature of the reforming catalyst is equal to or higher than the guaranteed durability temperature. (Step ST3).

  When the bed temperature of the reforming catalyst is lower than the guaranteed endurance temperature, the ECU 4 stops supplying air and fuel to the first exhaust passage 3B with respect to the air supply device 18 and the second fuel supply device 19. The command is executed (step ST4). As a result, the air supply device 18 and the second fuel supply device 19 stop the air and fuel if they are supplying air, and stop the air and fuel if they are not supplying air and fuel. To maintain.

  Thereafter, the ECU 4 reads the fuel injection amount from the first fuel supply device 14 in accordance with the bed temperature of the reforming catalyst and the operating state of the internal combustion engine from the aforementioned map, and supplies the fuel with the injection amount. Is instructed to the first fuel supply device 14 (step ST5). As a result, the first fuel supply device 14 injects fuel into the exhaust gas branch passage 13.

  Here, since the bed temperature of the reforming catalyst at that time is a temperature at which the reforming reaction is promoted, the exhaust gas in which the fuel from the first fuel supply device 14 flows through the exhaust gas diversion passage 13 is used. Together with the gas, it is guided to the reforming chamber 12b of the reformer 12 to generate a reformed gas. This reformed gas is introduced into the intake passage 2A through the reformed gas introduction passage 15 together with the exhaust gas remaining during the reforming reaction, and the intake air from the outside and the first to fourth fuel injection devices 9a to 9d It flows into the first to fourth cylinders 1a to 1d and burns together with the air-fuel mixture consisting of the atomized fuel.

  Thereby, in this internal combustion engine, the pump loss and the cooling loss are reduced, and the specific heat ratio is further increased, so that the fuel consumption rate can be reduced and the torque can be improved.

  On the other hand, introduction of exhaust gas into the intake path 2 increases combustion fluctuations due to a decrease in combustion temperature and combustion speed, so that the fuel consumption rate is deteriorated and torque fluctuations may occur. However, since this internal combustion engine introduces reformed gas (especially hydrogen gas) together with exhaust gas, the calorific value at the time of combustion increases and rapid combustion becomes possible. Can be expanded. As a result, the deterioration of the fuel consumption rate is improved and the torque fluctuation can be reduced.

  Thereafter, the ECU 4 returns to step ST1 and repeats the generation of the reformed gas while monitoring the bed temperature of the reforming catalyst.

  If it is determined in step ST3 that the bed temperature of the reforming catalyst is equal to or higher than the endurance guarantee temperature, the ECU 4 supplies air from the air supply device 18 according to the bed temperature of the reforming catalyst. The amount is read from the above-described map, and the air supply device 18 is instructed to supply air with the supplied amount (step ST6).

  As a result, the air supplied from the air supply device 18 flows into the exhaust passage 12c of the reformer 12 through the oxidation catalyst 20 while cooling the exhaust gas in the first exhaust passage 3B. The reforming catalyst in the vessel 12 is cooled.

  After the process of step ST6, the ECU 4 returns to step ST3 to make a comparison between the bed temperature of the reforming catalyst and the guaranteed durability temperature again, and the bed temperature of the reforming catalyst is still above the guaranteed durability temperature. In this case, the process proceeds to step ST6 and the same process is repeated. Accordingly, the bed temperature of the reforming catalyst can be lowered below the guaranteed endurance temperature, so that the reforming catalyst is prevented from being damaged and the durability is improved.

  As described above, in the internal combustion engine of this embodiment, the reforming catalyst of the reformer 12 does not reach the activation temperature. When the bed temperature has dropped, when the exhaust gas has not reached a temperature that can promote the reforming reaction of the reforming catalyst, the exothermic reaction of the oxidation catalyst 20 to which air and fuel have been introduced causes The temperature of the exhaust gas can be raised to raise the bed temperature of the reforming catalyst to the activation temperature or higher. Therefore, in this internal combustion engine, even in a situation where such a reforming reaction is difficult to be performed, the reforming catalyst is forced to raise the bed temperature of the reforming catalyst to perform a sufficient reforming reaction. Gas generation can be performed.

  As described above, according to the internal combustion engine of the present embodiment, the bed temperature of the reforming catalyst can be raised to an optimum temperature at which the reforming reaction can be promoted at an early stage, and thereafter the temperature can be constantly maintained. Even if the operating state of the internal combustion engine changes, the reformed gas can be introduced into the first to fourth cylinders 1a to 1d, and the engine performance improvement such as the reduction of the fuel consumption rate described above can be improved. This can be achieved in the driving state.

  Further, in the internal combustion engine of the present embodiment, when the bed temperature of the reforming catalyst has risen to a temperature that lowers the durability, the reforming catalyst 12 is forced to introduce air into the reformer 12. As a result of cooling, the durability of the reformer 12 can be improved.

  Here, the oxidation catalyst 20 deteriorates by repeating the exothermic reaction. However, in this embodiment, the oxidation catalyst 20 is disposed in the exhaust path 3 so as to be detachable. By doing so, the durability of the reformer 12 can be further improved. Therefore, according to the internal combustion engine of the present embodiment, the life of the reformer 12 that is more expensive than the oxidation catalyst 20 can be extended, so that the running cost can be reduced.

  In this embodiment, since the so-called 4-1 type exhaust manifold 3A is illustrated, the air supply device 18, the second fuel supply device 19, the oxidation catalyst 20, and the reformer 12 in the first exhaust passage 3B are provided. For example, when the exhaust manifold is of a so-called 4-2 type, the air supply device 18, the second fuel supply device 19, the oxidation catalyst 20, and the A reformer 12 is preferably provided.

  As described above, the internal combustion engine according to the present invention is suitable for a technique for quickly raising the bed temperature of the reforming catalyst to a predetermined activation temperature and maintaining the temperature.

It is a figure which shows the structure of the Example of the internal combustion engine which concerns on this invention. It is a flowchart explaining operation | movement of the internal combustion engine of an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine body 2 Intake path 2A Intake path 3 Exhaust path 3A Exhaust manifold 3B First exhaust path 4 ECU (electronic control unit)
12 reformer 12a cylinder 12b reforming chamber 12c exhaust passage 13 exhaust gas diversion passage (exhaust gas diversion passage)
14 Fuel supply device (first fuel supply device)
15 Reformed gas introduction passage (reformed gas introduction route)
18 Air supply device 19 Fuel supply device (second fuel supply device)
20 Oxidation catalyst 21 Bed temperature sensor

Claims (3)

An exhaust path for exhausting the exhaust gas discharged from each cylinder to the outside;
An exhaust gas diversion path for diverting a part of the exhaust gas flowing through the exhaust path;
A first fuel supply device capable of supplying fuel into the exhaust gas diversion path;
Downstream of the reforming chamber in which the fuel supplied from the first fuel supply device and the exhaust gas in the exhaust gas diversion path are introduced to generate reformed gas and the branch portion of the exhaust gas diversion path in the exhaust path A reformer having an exhaust passage through which exhaust gas from the side flows, and
A reformed gas introduction path for introducing the reformed gas generated by the reformer into an intake path;
An air supply device and a second fuel supply device provided downstream of the branch portion of the exhaust gas diversion path in the exhaust path and upstream of the reformer;
An oxidation catalyst provided between the air supply device and the second fuel supply device and the reformer in the exhaust path;
An internal combustion engine comprising:   When the bed temperature of the reforming catalyst carried in the reforming chamber of the reformer is lower than a predetermined activation temperature, air and fuel are supplied to the air supply device and the second fuel supply device. 2. An internal combustion engine according to claim 1, further comprising control means for causing the control to be performed.   The control means supplies air to the air supply device when the bed temperature of the reforming catalyst of the reformer is equal to or higher than a durability guarantee temperature that can guarantee the durability of the reforming catalyst. The internal combustion engine according to claim 2, wherein the internal combustion engine is configured to execute.

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