JP2017166387A - Control device of multi-ignition type engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly suppress degradation of combustibility and lowering of an engine output caused by accidental fire even when accidental fire occurs at some ignition plugs among a plurality of ignition plugs 19A, 19B, in a control device of a multi-ignition type engine having the plurality of ignition plugs 19A, 19B.SOLUTION: When accidental fire is detected at only some ignition plugs among a plurality of ignition plugs 19A, 19B by accidental fire detection means (accidental fire detection circuits 57A, 57B), a fuel injection valve (direct-injection injection valve 18) is controlled so that an air-fuel mixture is formed at a side of the ignition plugs in which the accidental fire is not detected, in comparison with a case when the accidental fire of the plurality of ignition plugs 19A, 19B is not detected in a combustion chamber of an engine 10, and the lowering of the engine output caused by the accidental fire of some ignition plugs is compensated by increasing a fuel injection amount from the fuel injection valve.SELECTED DRAWING: Figure 3

Description

  The present invention belongs to a technical field related to a control device for a multi-ignition engine having a plurality of ignition plugs for igniting an air-fuel mixture at a plurality of positions in a combustion chamber.

  In particular, in a hybrid vehicle, the operation and stop of the engine are often repeated, and therefore the combustion state during operation of the engine is poor. In particular, when the engine is stopped when the engine is in a cold state, the combustion state during operation of the engine is deteriorated. In such an engine, during operation of the engine, deposits tend to adhere and accumulate on members facing the combustion chamber (especially spark plugs). If the deposit adheres to the spark plug, there is a high possibility that the spark plug will be misfired.

  Here, for example, in Patent Document 1, when a misfire of one of the two ignition plugs is detected in a multi-ignition engine having two ignition plugs in each cylinder, the one plug is detected. Is used, and the ignition timing of the other spark plug is corrected according to a predetermined parameter (advance angle correction). That is, according to Patent Document 1, in an engine designed based on two-point ignition, when one-point ignition is performed, if a single plug arranged at a position offset from the center of the combustion chamber is ignited, the flame propagation distance For this reason, if the ignition timing is set to the same as that of the two-point ignition, the injected fuel is exhausted without being burned before the combustion is finished, so that the engine output is reduced. Therefore, in the case of single spark plug control, if the ignition timing is advanced within a range where knocking does not occur, the fuel that has been exhausted without combustion can be combusted and then exhausted. it can.

JP 2009-150335 A

  In the multi-ignition engine having a plurality of spark plugs as described above, when a part of the plurality of spark plugs misfires due to adhesion of the deposits, etc. In addition, it is conceivable to perform ignition with the remaining spark plugs and to correct the ignition timing of the ignition timing.

  However, as described in Patent Document 1 above, if only the ignition timing of a spark plug that has not misfired is advanced, the combustibility may be further deteriorated depending on how the fuel / air mixture is formed. At the same time, it is difficult to satisfactorily suppress a decrease in engine output, and there is room for improvement.

  The present invention has been made in view of such a point, and an object of the present invention is to control a part of the plurality of ignition plugs in a control device for a multi-ignition engine having a plurality of ignition plugs. Even if the plug misfires, it is desirable to satisfactorily suppress deterioration in combustibility and reduction in engine output due to the misfire.

  In order to achieve the above object, in the present invention, a fuel injection valve that injects fuel and a mixture of fuel and air from the fuel injection valve are ignited at a plurality of positions in the combustion chamber. Targeting a control device for a multi-ignition engine having a plurality of spark plugs, including misfire detection means for detecting misfire of each of the spark plugs, operation of the fuel injection valve and each of the spark plugs, Control means for controlling operation, and when the misfire detection means detects a misfire of only a part of the plurality of spark plugs, the control means in the combustion chamber The fuel injection valve is controlled so that the air-fuel mixture is formed on the side of the spark plug where no misfire has been detected, compared with when the misfire of the spark plug is not detected, and the part A reduction amount of the engine output by the misfire of the spark plug, has a configuration that is configured to compensate for the increase of the fuel injection amount from the fuel injection valve.

  With the above configuration, when only a part of the plurality of spark plugs misfires, the spark plugs that have not misfired in the combustion chamber are compared with the case where the plurality of spark plugs do not misfire. Since the fuel injection valve is controlled so that an air-fuel mixture is formed on the side, it is possible to maintain the same flammability as when the misfire of the plurality of spark plugs is not detected, and the flammability deteriorates due to misfire Can be suppressed satisfactorily. In addition, since the decrease in engine output due to misfire of some of the spark plugs is compensated for by the increase in the fuel injection amount from the fuel injection valve, the decrease in engine output due to misfire of some of the spark plugs can be well suppressed. Can do.

  In one embodiment of the control device for the multi-ignition engine, the engine is a rotary piston engine, and the plurality of spark plugs are a leading side spark plug and a trailing side spark plug arranged in parallel in the rotational direction of the rotor. The fuel injection valve is a direct injection valve that directly injects fuel into the combustion chamber of the engine, and the control means detects when the misfire of only the leading spark plug is detected by the misfire detection means. In the combustion chamber, the leading air-fuel mixture is formed on the trailing-side spark plug side as compared to when no leading-side and trailing-side spark plug misfires are detected. Compared to the case where no misfire is detected in the side and trailing side spark plugs, the fuel injection valve When the misfire of only the trailing side spark plug is detected while the timing of fuel injection is delayed, the misfires of the leading side and trailing side spark plugs are not detected in the combustion chamber. In comparison, the fuel by the fuel injection valve is compared with the case where no misfiring of the leading side and trailing side spark plugs is detected so that the air-fuel mixture is formed on the leading side spark plug side. It is configured to advance the injection timing.

  As a result, in the rotary piston engine, when only the leading side spark plug misfires, compared to when both the leading side and trailing side spark plugs are not misfiring in the combustion chamber due to the delay of the fuel injection timing. The air-fuel mixture can be easily formed on the side of the trailing-side ignition plug. When only the trailing-side ignition plug misfires, the leading side and trailing side ignitions in the combustion chamber are caused by the advance of the fuel injection timing. Compared to when the plugs are not misfired, the air-fuel mixture can be easily formed on the leading spark plug side.

  In the case of the rotary piston engine, the fuel injection valve is further provided with a fuel pressure adjusting means that adjusts the fuel pressure supplied to the fuel injection valve provided so that the fuel injection direction is directed to the rotation direction of the rotor, The control means further controls the operation of the fuel pressure adjusting means. When the misfire detection means detects a misfire of only the leading spark plug, the misfire of the leading and trailing spark plugs is detected. Compared to when both are not detected, the fuel pressure by the fuel pressure adjusting means is reduced. On the other hand, when only the trailing-side spark plug is misfired, the leading-side and trailing-side spark plugs are misfired. The fuel pressure by the fuel pressure adjusting means is increased compared to when both are not detected. Has been made, it is preferable.

  As a result, when only the leading spark plug misfires, in addition to retarding the fuel injection timing, the fuel pressure decreases, so that the air-fuel mixture is more reliably formed on the trailing spark plug side in the combustion chamber. When only the trailing-side spark plug misfires, in addition to the advance of the fuel injection timing, the fuel pressure increases, so that the air-fuel mixture is more reliably formed on the leading spark plug side in the combustion chamber. be able to.

  In another embodiment of the control device for the multi-ignition engine, the engine is a reciprocating engine in which a piston reciprocates in a cylinder, and the plurality of spark plugs are arranged on an intake side of a ceiling portion of the combustion chamber. An intake-side ignition plug provided, and an exhaust-side ignition plug disposed on the exhaust side of the ceiling, wherein the fuel injection valve is disposed in the center of the ceiling of the combustion chamber, A first injection mode in which at least the fuel is injected from the center of the cylinder toward the entire periphery thereof as viewed from the center axis direction of the cylinder, and the fuel is directed from the center of the cylinder to the intake side spark plug The control means is configured to be switchable between a second injection form for injecting the fuel and a third injection form for injecting the fuel from the center of the cylinder toward the exhaust side spark plug. In When the misfires of the intake side and exhaust side ignition plugs are not detected, the fuel injection valve is controlled so that the fuel is injected in the first injection mode, while the misfire detection means controls the exhaust gas. When the misfire of only the side ignition plug is detected, the fuel injection valve is controlled so that the fuel is injected in the second injection mode, and when the misfire of only the intake side ignition plug is detected, The fuel injection valve is controlled to inject the fuel in the third injection mode.

  As a result, in the reciprocating engine, when only the exhaust side ignition plug misfires, the fuel injection according to the second injection mode causes a comparison with when both the intake side and exhaust side ignition plugs are not misfiring in the combustion chamber. Thus, the air-fuel mixture can be easily formed on the intake side spark plug side, and when only the intake side spark plug misfires, the fuel injection according to the third injection mode causes the intake side and the exhaust side in the combustion chamber. The air-fuel mixture can be easily formed on the exhaust side ignition plug side as compared with the case where both of the ignition plugs are not misfired.

  In still another embodiment of the control device for the multi-ignition engine, the engine is a reciprocating engine in which a piston reciprocates in a cylinder, and the plurality of spark plugs are disposed on an intake side of a ceiling portion of the combustion chamber. An intake side ignition plug disposed on the exhaust side of the ceiling portion, and the fuel injection valve is a peripheral portion on the intake side or exhaust side of the ceiling portion of the combustion chamber. And further comprising a fuel pressure adjusting means for adjusting the fuel pressure supplied to the fuel injection valve, wherein the control means further controls the operation of the fuel pressure adjusting means. When the misfire of only the spark plug on the side far from the fuel injection valve is detected, the fuel pressure adjusting means is compared to when the misfire of only the spark plug on the side near the fuel injection valve is detected. According is configured to reduce the fuel pressure.

  Thus, in the reciprocating engine, when only the ignition plug closer to the fuel injection valve among the intake side ignition plug and the exhaust side ignition plug misfires, the intake side in the combustion chamber is caused by a relatively large fuel pressure. Compared to when the spark plug and the exhaust side spark plug are not misfiring, the air-fuel mixture can be easily formed on the side of the spark plug far from the fuel injection valve. When only the far-side spark plug misfires, the fuel pressure decreases, so the side closer to the fuel injection valve in the combustion chamber than when both the intake-side spark plug and the exhaust-side spark plug are not misfied An air-fuel mixture can be easily formed on the spark plug side.

  In still another embodiment of the control device for the multi-ignition engine, the engine is a reciprocating engine in which a piston reciprocates in a cylinder, and the plurality of spark plugs are provided at a central portion of a ceiling portion of the combustion chamber. A central spark plug disposed in the central portion, and a peripheral spark plug disposed in a peripheral portion of the ceiling portion, wherein the fuel injection valve is disposed in the vicinity of the central spark plug, and the control means When the misfire detection means detects a misfire of only the peripheral spark plug, the timing of fuel injection by the fuel injection valve is retarded compared to when a misfire of only the center spark plug is detected. It is configured to

  Thus, in the reciprocating engine, when only the center spark plug misfires, the fuel injection timing at a relatively advanced angle causes the center and peripheral spark plugs to not both misfire in the combustion chamber. The air-fuel mixture can be easily formed on the side of the peripheral spark plug (the spark plug far from the fuel injection valve), and when only the peripheral spark plug misfires, In the combustion chamber, an air-fuel mixture is easily formed on the side of the central spark plug (the spark plug closer to the fuel injection valve) than when both the central spark plug and the peripheral spark plug are not misfired. be able to.

  In still another embodiment of the control device for the multi-ignition engine, the engine is a reciprocating engine in which a piston reciprocates in a cylinder, and the plurality of spark plugs are provided at a central portion of a ceiling portion of the combustion chamber. A central spark plug disposed at the center and a peripheral spark plug disposed at a peripheral edge of the ceiling, wherein the fuel injection valve is disposed in the vicinity of the central spark plug, and the fuel injection valve Fuel pressure adjusting means for adjusting the fuel pressure supplied to the valve is further provided, and the control means further controls the operation of the fuel pressure adjusting means, and the misfire detecting means only misfires only the peripheral spark plug. When the fuel pressure is detected, the fuel pressure is reduced by the fuel pressure adjusting means as compared to when the misfire of only the center spark plug is detected.

  In this way, in the reciprocating engine, when only the central spark plug misfires, the peripheral pressure of the central and peripheral spark plugs is not misfiring in the combustion chamber due to relatively large fuel pressure. The air-fuel mixture can be easily formed on the side of the spark plug (the spark plug far from the fuel injection valve), and when only the peripheral spark plug misfires, Compared to the case where both the central and peripheral spark plugs are not misfiring, the air-fuel mixture can be easily formed on the side of the central spark plug (the spark plug closer to the fuel injection valve).

  As described above, according to the control device for a multi-ignition engine of the present invention, when misfire of only some of the plurality of spark plugs is detected by the misfire detection means, The fuel injection valve is controlled so that an air-fuel mixture is formed on the side of the spark plug in which no misfire is detected, compared with the case in which no misfire is detected in the spark plug, and the above-mentioned part of the spark plugs By compensating for the decrease in engine output due to misfire, the increase in the fuel injection amount from the fuel injection valve, even if some of the spark plugs misfire, combustion due to misfire It is possible to satisfactorily suppress the deterioration of the performance and the engine output.

1 is a schematic diagram of a hybrid vehicle equipped with a multi-ignition engine control device according to Embodiment 1 of the present invention. It is a block diagram which shows the structure of the multi ignition engine of the said hybrid vehicle, and its control system. It is sectional drawing which shows the state which has one working chamber of the said engine in the compression top vicinity. FIG. 4 is a cross-sectional view of a main part showing a state in which an air-fuel mixture is formed substantially evenly in portions corresponding to both a leading side and a trailing side spark plug in a working chamber near the compression top of the engine. FIG. 5 is a view corresponding to FIG. 4 showing a state in which an air-fuel mixture is formed toward the trailing spark plug in the working chamber near the compression top of the engine. FIG. 5 is a view corresponding to FIG. 4 showing a state in which an air-fuel mixture is formed toward the leading spark plug side in the working chamber near the compression top of the engine. It is a flowchart which shows the processing operation from the start of the said engine by a control unit to a stop. It is sectional drawing of the multi-ignition engine in Embodiment 2 of this invention. It is the figure which looked at the ceiling part of the combustion chamber of the said engine in Embodiment 2 from the combustion chamber side. FIG. 8 is a diagram corresponding to FIG. 7 in the second embodiment. It is sectional drawing of the multi-ignition engine in Embodiment 3 of this invention. It is the figure which looked at the ceiling part of the combustion chamber of the said engine in Embodiment 3 from the combustion chamber side. FIG. 8 is a diagram corresponding to FIG. 7 in the third embodiment. It is sectional drawing of the multi-ignition engine in Embodiment 4 of this invention. It is the figure which looked at the ceiling part of the combustion chamber of the said engine in Embodiment 4 from the combustion chamber side. It is a graph which shows the relationship between the penetration of the fuel injected from the fuel injection valve, the spray spread angle of the fuel, and the fuel pressure supplied to the fuel injection valve. FIG. 8 is a diagram corresponding to FIG. 7 in the fourth embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic diagram of a hybrid vehicle 1 (hereinafter referred to as a vehicle 1) equipped with a multi-ignition engine control apparatus according to Embodiment 1 of the present invention. The vehicle 1 is a series hybrid vehicle, and includes a multi-ignition engine 10 (hereinafter simply referred to as the engine 10) having a plurality (two in the present embodiment) of spark plugs 19A and 19B (see FIG. 2), A generator 20 that is driven by the engine 10 to generate power, a high-voltage / large-capacity battery 30 that stores (charges) the power generated by the generator 20, and a generator that is driven by the engine 10 And a drive motor 40 driven by at least one of 20 generated power and stored power (discharge power) of the battery 30. In the present embodiment, the generator 20 is a motor generator having a function of a motor, and the engine 10 is driven (cranked) by the generator 20 as a motor to start the engine 10. .

  A first inverter 50 is provided between the generator 20 and the battery 30, and a second inverter 51 is provided between the battery 30 and the drive motor 40. The first inverter 50 and the second inverter 51 are connected to each other, and the battery 30 is connected to the connection line. The power generated by the generator 20 is supplied to the battery 30 via the first inverter 50 and also supplied to the drive motor 40 via the first and second inverters 50 and 51. Discharged power from the battery 30 is supplied to the drive motor 40 via the second inverter 51.

  The output of the drive motor 40 is transmitted to the drive wheels 61 (the left and right front wheels steered by the steering wheel 62) via the differential device 60, whereby the vehicle 1 travels.

  The drive motor 40 is capable of generating regenerative power and operates as a generator when the vehicle 1 is decelerated, and the generated power (regenerative power) is charged in the battery 30. In the charging travel mode described later, the engine 10 is started and the battery 30 is charged with the generated power of the generator 20. The battery 30 can be externally charged by a power source external to the vehicle 1.

  The engine 10 is a power generation engine used to drive the generator 20 to generate power. The engine 10 is a gaseous fuel engine configured so that hydrogen gas stored in the hydrogen tank 70 can be supplied as gaseous fuel. The fuel for the engine 10 may be other gaseous fuel such as natural gas (CNG) or liquid fuel such as gasoline.

  The hydrogen tank 70 and the engine 10 are connected by a hydrogen supply pipe 72, and hydrogen gas in the hydrogen tank 70 is passed through the hydrogen supply pipe 72 to the engine 10 (in detail, a port injection valve 17 and a direct injection injection described later). To the valve 18).

  A pressure reducing valve 74 is disposed at a connection portion between the hydrogen supply pipe 72 and the hydrogen tank 70. In a state where the hydrogen tank 70 is filled with hydrogen gas, the pressure in the hydrogen tank 70 (hydrogen gas pressure) is set to 35 MPa, for example. When the hydrogen gas passes through the pressure reducing valve 74, the pressure of the hydrogen gas is reduced.

  Further, the hydrogen supply pipe 72 is adjusted as fuel pressure adjusting means for adjusting the fuel pressure supplied to the direct injection valve 18 (in this embodiment, the fuel pressure supplied to the port injection valve 17). A pressure valve 75 is provided, and the pressure of the hydrogen gas that has passed through the pressure reducing valve 74 is reduced to a desired pressure by the pressure adjusting valve 75 and supplied to the direct injection valve 18. The desired pressure (that is, the fuel pressure supplied to the direct injection valve 18) can be electrically adjusted by a control signal from the control unit 100 described later to the pressure regulating valve 75.

  As shown in FIG. 2, in this embodiment, the engine 10 is a twin-rotor (two-cylinder) rotary piston engine, and includes a rotor housing formed in two saddle-shaped rotor housings 11 (inside cylinders). The chambers 11a are configured so that the substantially triangular rotors 12 are respectively accommodated therein. The two rotor housings 11 are integrated with the side housings so as to be sandwiched between three side housings (not shown), and each rotor housing chamber 11a is composed of each rotor housing 11 and the side housings on both sides thereof. Is formed. Each rotor housing 11 has a trochoidal inner peripheral surface having a substantially elliptical shape (substantially elliptical shape defined by a major axis Y and a minor axis Z (see FIG. 3) orthogonal to each other). In FIG. 2, the two rotor housings 11 (two cylinders) are shown in an unfolded state, and the eccentric shafts 13 respectively drawn in the central portions in the two rotor housings 11 are the same.

  Each of the rotors 12 has apex seals (not shown) at the apexes of the triangles, and the apex seals are in sliding contact with the inner surface of the trochoid of the rotor housing 11. Three working chambers (corresponding to combustion chambers) are defined in 11a (each cylinder). Each rotor 12 rotates around the eccentric shaft 13 in a state where the three apex seals of the rotor 12 are in contact with the inner surface of the trochoid of the rotor housing 11, and the axis X of the eccentric shaft 13 is rotated. It is going to revolve around. While the rotor 12 makes one revolution, the working chambers formed between the tops of the rotor 12 move in the circumferential direction, and the intake, compression, expansion (combustion), and exhaust strokes are performed. The rotating force is output from the eccentric shaft 13 as the output shaft through the rotor 12.

  An intake passage 14 is connected to each of the rotor accommodating chambers 11a so as to communicate with an intake opening that opens to the working chamber in the intake stroke, and communicates with an exhaust opening that opens to the working chamber in the exhaust stroke. An exhaust passage 15 is connected to the front. There is one intake passage 14 on the upstream side, but on the downstream side, the intake passage 14 branches into two branch passages and communicates with each of the rotor accommodating chambers 11a. The cross-sectional area (valve opening degree) of the intake passage 14 is adjusted by being driven by a throttle valve actuator 90 such as a stepping motor on the upstream side of the branch portion of the intake passage 14 (downstream side of an intercooler 86 described later). A throttle valve 16 is provided. The throttle valve 16 adjusts the amount of intake air into each rotor accommodating chamber 11a (the working chamber in the intake stroke). During the engine control described later in the present embodiment (during the middle load or high load operation of the engine 10), the throttle valve 16 is basically fully opened.

  A port injection valve 17 that injects hydrogen gas from the hydrogen tank 70 into the intake passage 14 is disposed in each branch passage downstream of the branch portion of the intake passage 14. The hydrogen gas injected by the port injection valve 17 is supplied to the working chamber in the intake stroke while being mixed with air.

  When the temperature of the engine 10 is extremely cold (even when the engine is cold), the temperature of the cooling water of the engine 10 (hereinafter referred to as engine cooling water) is considerably low, and the port injection valve 17 is lower than a preset temperature. ) Used at start-up. At other times, fuel (hydrogen gas) is directly injected into the working chamber (combustion chamber) from a direct injection valve 18 described later. When the engine 10 is extremely cold, the fuel injection opening of the direct injection valve 18 may be blocked by freezing of water generated by fuel combustion. Fuel is injected from the valve 17. It should be noted that fuel can be injected by the direct injection valve 18 and the port injection valve 17 when the engine 10 is started and operated. Alternatively, the port injection valve 17 can be eliminated. In the following description, it is assumed that fuel (hydrogen gas) is injected by the direct injection valve 18.

  Two exhaust passages 15 are provided on the upstream side so as to communicate with the respective rotor accommodating chambers 11a, but are joined together on the downstream side. A low temperature active three-way catalyst 81 and a NOx occlusion reduction catalyst 82 for purifying exhaust gas are disposed downstream of the merging portion of the exhaust passage 15. The low temperature active three-way catalyst 81 is a three-way catalyst having a catalyst activation temperature lower than that of the NOx storage reduction catalyst 82, and is disposed upstream of the NOx storage reduction catalyst 82. In FIG. 2, arrows shown in the intake passage 14 and the exhaust passage 15 indicate the flow of intake and exhaust.

  The NOx occlusion reduction catalyst 82 is configured, for example, by supporting a NOx occlusion agent such as barium (Ba) or potassium (K) on a carrier containing a noble metal such as platinum (Pt) or palladium (Pd). The NOx in the exhaust gas of the engine 10 is occluded in a lean air-fuel ratio atmosphere, and the occluded NOx is released in a rich air-fuel ratio atmosphere to cause the NOx to react with HC and CO in the exhaust gas. Have the function of reducing

  In each rotor housing 11 (each cylinder), a direct injection valve 18 (of the present invention) that directly injects hydrogen gas from the hydrogen tank 70 into the working chamber (combustion chamber) in the compression stroke of the rotor accommodating chamber 11a. Equivalent to a fuel injection valve). The direct injection valve 18 is located in the vicinity of the long axis Y of the rotor housing 11 when viewed from the direction in which the axial center X of the eccentric shaft 13 extends (that is, in FIG. 3). Inclined by a predetermined angle with respect to the long axis Y so that the injection direction of (hydrogen gas) is directed in the rotational direction of the rotor 12. As a result, when viewed from the direction in which the axis X of the eccentric shaft 13 extends, the fuel from the direct injection valve 18 is injected with respect to the long axis Y to the side where spark plugs 19A and 19B described later are disposed. Will be. The predetermined angle is preferably 5 ° to 15 ° on the acute angle side formed by the axis of the direct injection valve 18 and the long axis Y.

  Each rotor housing 11 is ignited with a plurality of (in this embodiment, two) ignition chambers (combustion chambers) in a mixture of fuel and air injected from the direct injection valve 18. Two spark plugs 19A, 19B are provided for performing in position. These spark plugs 19A, 19B are a leading side spark plug 19A and a trailing side spark plug 19B arranged in parallel in the rotational direction of the rotor 12. The leading side and trailing side spark plugs 19A and 19B are arranged on the leading side and trailing side of the rotor housing 11 in the rotational direction of the rotor across the minor axis Z when viewed from the direction in which the axis X of the eccentric shaft 13 extends. They are arranged at both positions (near the short axis Z). The leading spark plug 19A is ignited in the vicinity of the front of the compression top, and the trailing spark plug 19B is ignited at the same time as or immediately after the compression top (TDC). Thus, the leading side and trailing side spark plugs 19A and 19B ignite the air-fuel mixture in the working chamber in the compression or expansion stroke.

  The engine 10 is provided with an exhaust turbocharger 85 that supercharges intake air into the working chamber (combustion chamber) in the intake stroke in each rotor accommodating chamber 11a of the engine 10. The exhaust turbocharger 85 includes a compressor 85a disposed upstream of the throttle valve 16 in the intake passage 14 and a downstream side of the merging portion in the exhaust passage 15 and upstream of the three-way catalyst 81. And a turbine 85b disposed in the turbine. The turbine 85b is rotated by the exhaust gas flow, and the rotation of the turbine 85b activates the compressor 85a connected to the turbine 85b to compress the air taken into the intake passage 14. The compressed air is cooled by an intercooler 86 disposed downstream of the compressor 85a and upstream of the throttle valve 16 in the intake passage 14, and then accommodated in each rotor via each branch passage. Inhaled into the working chamber in the intake stroke of the chamber 11a.

  The vehicle 1 includes a battery current / voltage sensor 101 that detects a current flowing in and out of the battery 30 and a voltage of the battery 30, and an accelerator that detects an amount of depression of an accelerator pedal by an occupant of the vehicle 1 (accelerator opening by an occupant's operation). An opening sensor 102, a vehicle speed sensor 103 that detects the vehicle speed of the vehicle 1, a rotation angle sensor 104 that is provided on the eccentric shaft 13 and detects the rotation angle position of the eccentric shaft 13, and a low-temperature active three-way catalyst in the exhaust passage 15 An air-fuel ratio sensor 105 (configured by a linear O2 sensor in this embodiment) that is disposed between the turbine 81 and the turbine 85 b and detects the air-fuel ratio of the exhaust gas of the engine 10, and the rotor housing 11 It faces the formed water jacket (not shown) and flows through the water jacket. Engine water temperature sensor 106 (engine water temperature detecting means) for detecting the temperature of the engine cooling water (engine water temperature) and tank pressure for detecting the pressure in the hydrogen tank 70 (that is, the remaining volume of hydrogen gas in the hydrogen tank 70). A sensor 107, an air flow sensor 108 for detecting the intake air flow rate sucked into the intake passage 14, a battery temperature sensor 109 for detecting the temperature of the battery 30, the operation control of the engine 10, the first and second inverters 50, A control unit 100 that performs operation control 51 (that is, operation control of the generator 20 and the drive motor 40) and the like is provided. The rotation angle sensor 104 also serves as an engine rotation speed sensor that detects the rotation speed of the engine 10.

  The control unit 100 is a controller based on a well-known microcomputer, and includes a central processing unit (CPU) that executes a program, a memory that includes, for example, a RAM and a ROM, and stores a program and data; An input / output (I / O) bus. The control unit 100 includes a battery current / voltage sensor 101, an accelerator opening sensor 102, a vehicle speed sensor 103, a rotation angle sensor 104, an air-fuel ratio sensor 105, an engine water temperature sensor 106, a tank pressure sensor 107, an air flow sensor 108, a battery temperature sensor. Various information signals from 109 etc. are input.

  The generator 20 transmits information on the voltage and current generated by the generator 20 to the control unit 100. The control unit 100 inputs the information and generates power generated by the generator 20 from the information. (Power generation amount) is detected.

  The drive motor 40 transmits information on the rotational speed of the drive motor 40 and information on the regenerative power generation voltage and regenerative power generation current generated by the drive motor 40 to the control unit 100, and the control unit 100 transmits the information. The input is used to control the operation of the drive motor 40.

  The control unit 100 then controls the throttle valve actuator 90, the port injection valve 17, the direct injection valve 18, the leading side ignition plug 19A, the trailing side ignition plug 19B, and the pressure regulating valve 75 based on the input signal. A control signal is output to control the engine 10, and a control signal is output to the first and second inverters 50 and 51 to control the generator 20 and the drive motor 40. The control unit 100 constitutes control means for controlling the operation of the engine 10 including the operations of the direct injection valve 18, the leading side spark plug 19A, and the trailing side spark plug 19B.

  As shown in FIG. 3, the leading spark plug 19A is ignited by generating a high voltage in the ignition coil 56A by the igniter 55A. The trailing-side ignition plug 19B is ignited by generating a high voltage in the ignition coil 56B by the igniter 55B. The control unit 100 transmits the control signal (ignition signal) to the igniter 55A to control the ignition timing of the leading spark plug 19A, and transmits the control signal (ignition signal) to the igniter 55B. The ignition timing of the side spark plug 19B is controlled.

  The ignition coil 56A is provided with a misfire detection circuit 57A for the leading ignition plug 19A, and the ignition coil 56B is provided with a misfire detection circuit 57B for the trailing ignition plug 19B. When the leading spark plug 19A misfires, the misfire detection circuit 57A of the ignition coil 56A detects the misfire, and the misfire detection circuit 57A transmits a misfire detection signal of the leading spark plug 19A to the control unit 100. When the trailing side ignition plug 19B misfires, the misfire is detected by the misfire detection circuit 57B of the ignition coil 56B, and the misfire detection signal of the trailing side ignition plug 19B is transmitted from the misfire detection circuit 57B to the control unit 100. Is done. The control unit 100 can recognize the misfire of each of the spark plugs 19A and 19B based on the misfire detection signal of the leading and trailing spark plugs 19A and 19B. Accordingly, the misfire detection circuits 57A and 57B of the ignition coils 56A and 56B constitute misfire detection means for detecting misfire of the spark plugs 19A and 19B.

  The vehicle 1 is driven by the battery 30 in the battery running mode (at this time, the engine 10 is stopped), the engine 10 is operated, and the output of the engine 10 causes the battery to pass through the generator 20. And a charging travel mode in which the vehicle travels while charging 30. In the present embodiment, since the vehicle 1 is a series hybrid vehicle, in the charging travel mode, charging of the battery 30 and driving of the drive motor 40 are performed with electric power generated by the generator 20 that generates electric power from the output of the engine 10. Do.

  The control unit 100 detects the remaining capacity (SOC) of the battery 30 based on the current flowing into and out of the battery 30 and the voltage of the battery 30 detected by the battery current / voltage sensor 101.

  Then, when the detected SOC of the battery 30 is lower than a first predetermined value (for example, 30%) in the battery running mode, the control unit 100 switches to the charging running mode while the charging running mode Sometimes, when the detected SOC of the battery 30 becomes higher than a second predetermined value (for example, 70%) set to a value higher than the first predetermined value, the battery driving mode is switched. Thereby, the SOC of battery 30 can be maintained within a preferable range that is neither too low nor too high.

  In the battery running mode, the control unit 100 determines whether or not there is an operation request for the engine 10 based on the required output of the drive motor 40 and the SOC value of the battery 30 (in this embodiment, the same as the presence or absence of a power generation request). If there is an operation request (power generation request) for the engine 10, the engine 10 is cranked by the generator 20 as a motor to start the engine 10, and after that start, the generator 20 generates power. Therefore, the engine 10 is operated. That is, when the SOC of the battery 30 is lower than the first predetermined value or the required output of the drive motor 40 exceeds the maximum dischargeable power of the battery 30 in the battery running mode. Sometimes, the engine 10 is operated on the assumption that there is a request for operating the engine 10.

  Here, the maximum dischargeable power varies depending on the temperature of the battery 30. The relationship between the temperature of the battery 30 and the maximum dischargeable power is stored as a map in the memory of the control unit 100, and the control unit 100 uses the map to detect the battery detected by the battery temperature sensor 109. The maximum dischargeable power is detected from 30 temperatures.

  In the charging travel mode, the control unit 100 basically operates the engine 10 at a predetermined rotational speed, and the engine rotational speed during the engine steady operation (the predetermined rotational speed) is the highest efficiency point of the engine 10. Is a value in an efficient region including 1800 rpm to 2200 rpm, for example, 2000 rpm in this embodiment. The engine load during the engine steady operation is a medium load or a high load larger than a predetermined load. At this time, the battery 30 is charged and the drive motor 40 is driven with the power generated by the generator 20 that generates power by the output of the engine 10 (the remaining power obtained by subtracting the required output of the drive motor 40 from the generated power). Is charged to the battery 30). Further, when the required output of the drive motor 40 becomes larger than the engine output (generated power) at 2000 rpm as in the case of the acceleration request of the vehicle 1 or more during the steady engine operation, the shortage is reduced. It is supplemented by the discharge power of the battery 30 (not charged). However, if the required output of the drive motor 40 cannot be satisfied even if the discharge power of the battery 30 reaches the maximum dischargeable power of the battery 30, the engine speed is exceptionally made higher than the predetermined speed. .

  The operation of the engine 10 when the required output of the drive motor 40 exceeds the maximum dischargeable power of the battery 30 in the battery running mode is also a steady operation at the predetermined rotational speed (2000 rpm), and the discharge power of the battery 30 is reduced. It adjusts so that the required output of the drive motor 40 may be satisfied.

  When the engine 10 is in operation, the control unit 100 basically sets the combustion air-fuel ratio in the combustion chamber of the engine 10 to a value that is lower than a predetermined lean air-fuel ratio (a combustion air-fuel ratio at the lean limit of hydrogen gas (for example, an excess air ratio). λ = 2.3)). When the NOx occluded in the NOx occlusion reduction catalyst 82 is released, the combustion air-fuel ratio in the combustion chamber is made rich (for example, the excess air ratio λ = 0.9).

  In the vehicle 1 as described above, the operation and stop of the engine 10 are frequently repeated, and therefore, the combustion state during operation of the engine 10 is poor. In particular, when the operation of the engine 10 is stopped when the engine 10 is in a cold state, the combustion state during the operation of the engine 10 is deteriorated. In such an engine 10, during operation of the engine 10, deposits easily adhere to and accumulate on members facing the combustion chamber (particularly the leading and trailing spark plugs 19 </ b> A and 19 </ b> B). Such a deposit increases the possibility of causing misfire of one of the leading and trailing spark plugs 19A and 19B (part of the spark plug).

  Therefore, in this embodiment, even if one of the spark plugs misfires, it is possible to satisfactorily suppress deterioration in combustibility and reduction in engine output due to misfire.

  That is, when the misfire detection circuit 57A, 57B detects the misfire of only one spark plug, the control unit 100 is in the working chamber in the compression stroke after the misfire detection in the cylinder with the misfired spark plug. In the (combustion chamber), the air-fuel mixture is formed on the side of the spark plug in which no misfire is detected as compared with the case in which no misfire is detected in the leading and trailing spark plugs 19A and 19B. In addition, the direct injection valve 18 is controlled.

  Specifically, when the misfire detection circuit 57A, 57B detects a misfire of only the leading spark plug 19A, the control unit 100 compresses after the misfire detection in the cylinder with the misfired leading spark plug 19A. In the working chamber in the stroke, the air-fuel mixture is formed on the side of the trailing-side spark plug 19B as compared with the case where both the leading side and trailing-side spark plugs 19A and 19B are not misfired. The timing of fuel injection by the direct injection valve 18 is retarded as compared with the case where no misfire is detected in the leading side and trailing side spark plugs 19A, 19B, while only the trailing side spark plug 19B is misfired. Is detected, the misfired trailing spark plug 19B In the working chamber in the compression stroke after the misfire detection, the leading side spark plug 19A side is compared with the case where no misfire is detected in the leading side and trailing side spark plugs 19A, 19B. Therefore, the timing of fuel injection by the direct injection valve 18 is advanced as compared with the case where misfiring of the leading side and trailing side ignition plugs 19A, 19B is not detected.

  When the misfires of the leading and trailing spark plugs 19A and 19B are not detected, the fuel injection timing by the direct injection valve 18 is the working chamber in the vicinity of the compression top as shown in black in FIG. In this case, the air-fuel mixture is set to be substantially evenly formed in portions corresponding to both the leading and trailing spark plugs 19A and 19B.

  On the other hand, when a misfire of only the leading spark plug 19A is detected, in the working chamber in the vicinity of the compression top, as shown in black in FIG. The air-fuel mixture is formed toward the trailing spark plug 19B. Then, in the same manner as when the misfires of the leading and trailing spark plugs 19A and 19B are not detected, control signals (ignition signals) are transmitted to the igniters 55A and 55B of the spark plugs 19A and 19B.

  Even when the control signal is transmitted, the leading spark plug 19A is likely to misfire again due to the adhesion of the deposit. However, even if the leading spark plug 19A misfires, in the working chamber near the compression top, the air-fuel mixture is formed toward the trailing spark plug 19B, so the misfire of both spark plugs 19A and 19B. Combustibility similar to that when no is detected can be maintained, and deterioration of combustibility due to misfire can be satisfactorily suppressed.

  Further, when misfire is detected only in the trailing-side ignition plug 19B, the advance of the fuel injection timing by the direct injection valve 18 causes the working chamber in the vicinity of the compression top as shown in black in FIG. The air-fuel mixture is formed toward the leading side spark plug 19A. Then, in the same manner as when the misfires of the leading and trailing spark plugs 19A and 19B are not detected, control signals (ignition signals) are transmitted to the igniters 55A and 55B of the spark plugs 19A and 19B. At this time, even if the trailing-side ignition plug 19B misfires, in the working chamber near the compression top, the air-fuel mixture is formed toward the leading-side ignition plug 19B, so that both the ignition plugs 19A and 19B Combustibility similar to that when no misfire is detected can be maintained, and deterioration of combustibility due to misfire can be satisfactorily suppressed.

  If the misfire of the leading spark plug 19A or the trailing spark plug 19B is eliminated and the misfire of both the spark plugs 19A and 19B is not detected, the fuel injection timing is restored. Further, when a misfire of both the spark plugs 19A and 19B is detected, notification that an abnormality has occurred is performed by lighting an abnormal lamp (not shown).

  In the present embodiment, when a misfire of only the leading spark plug 19A or a misfire of only the trailing spark plug is detected, a piece of the mixture toward the trailing spark plug 19B or the leading spark plug 19A is detected. In order to make the deviation even more reliable, after the misfire is detected, the fuel pressure (fuel pressure) by the pressure regulating valve 75 is adjusted in addition to the change of the fuel injection timing.

  Specifically, when the misfire of the leading and trailing spark plugs 19A and 19B is not detected, the control unit 100 controls the fuel pressure by the pressure regulating valve 75 in the working chamber near the compression top. In addition, the pressure is set so that the air-fuel mixture is formed substantially evenly in portions corresponding to both the trailing-side spark plugs 19A and 19B. When the misfire detection circuit 57A, 57B detects a misfire of only the leading spark plug 19A, the control unit 100 compares the misfire of the leading and trailing spark plugs 19A, 19B with each other. When the misregistration of only the trailing side spark plug 19B is detected while the fuel pressure is reduced by the pressure regulating valve 75, the misfire of the leading side and trailing side spark plugs 19A, 19B is not detected. In comparison, the fuel pressure by the pressure regulating valve 75 is increased.

  That is, when the misfire of only the leading spark plug 19A, which is the spark plug far from the direct injection valve 18, is detected, the misfire of the leading and trailing spark plugs 19A, 19B occurs in the working chamber. Compared to the case where neither is detected, the fuel pressure is reduced so that the air-fuel mixture is formed on the side of the trailing-side spark plug 19B, which is the spark plug closer to the direct injection valve 18. (That is, the penetration of fuel injected from the direct injection valve 18 is reduced). On the other hand, when the misfire of only the trailing side spark plug 19B, which is the spark plug closer to the direct injection valve 18, is detected, the misfires of the leading side and trailing side spark plugs 19A and 19B are detected in the working chamber. The fuel pressure is increased so that the air-fuel mixture is formed on the leading spark plug 19A side, which is the spark plug far from the direct injection valve 18, compared to when no gas is detected. (That is, increase the penetration of fuel injected from the direct injection valve 18).

  The fuel pressure adjustment by the pressure regulating valve 75 when the misfire of only the leading spark plug 19A or the misfire of only the trailing spark plug 19B is detected is not necessarily performed.

  When the misfire detection circuit 57A, 57B detects misfire of only one of the spark plugs, the control unit 100 uses the fuel from the direct injection injector 18 to reduce the decrease in engine output due to misfire of the one of the spark plugs. Make up by increasing the injection amount. In the engine 10, the decrease in engine output due to the misfire of only the trailing side spark plug 19B is greater than the decrease in engine output due to the misfire of only the leading side spark plug 19A. Therefore, the misfire of only the trailing side spark plug 19B is detected. When this is done, the fuel injection amount is increased more than when the misfire of only the leading spark plug 19A is detected.

  Hereinafter, the control of the engine 10 when the misfires of the leading and trailing spark plugs 19A and 19B are not detected is referred to as normal control.

  Next, the processing operation from the start to the stop of the engine 10 by the control unit 100 will be described based on the flowchart of FIG. It is assumed that the battery running mode is set at the start of this flowchart.

  In the first step S1, various input signals from various sensors are read, and in the next step S2, the required output of the drive motor 40 is calculated based on the signals from the accelerator opening sensor 102 and the vehicle speed sensor 103.

  In the next step S3, it is determined whether or not there is a request for operation of the engine 10 based on the required output of the drive motor 40 and the SOC of the battery 30. That is, when the SOC of the battery 30 is lower than the first predetermined value, or when the required output of the drive motor 40 exceeds the maximum dischargeable power of the battery 30, there is a request for operation of the engine 10.

  In the next step S4, start control of the engine 10 is executed. That is, the engine 10 is cranked by the generator 20 without operating the direct injection valve 18, the leading side spark plug 19A, and the trailing side spark plug 19B, and the rotational speed of the engine 10 is set to a preset rotational speed. When the number reaches (for example, 800 to 1000 rpm), the direct injection valve 18, the leading side spark plug 19 </ b> A, and the trailing side spark plug 19 </ b> B are operated to start the engine 10.

  In the next step S5, it is determined whether or not misfire of only one spark plug is detected by the misfire detection circuits 57A and 57B. When the determination in step S5 is NO, the process proceeds to step S6 to execute normal control, and then proceeds to step S10.

  On the other hand, when the determination in step S5 is YES, the process proceeds to step S7, in which it is determined whether or not misfire of only the leading spark plug 19A has been detected.

  When the determination in step S7 is YES, the process proceeds to step S8, where the fuel injection timing by the direct injection valve 18 is retarded from the fuel injection timing in the normal control, and the fuel pressure by the pressure regulating valve 75 is increased. Is increased below the fuel pressure in the normal control, and further, the fuel injection amount from the direct injection valve 18 is increased to compensate for the decrease in the engine output due to misfire of the leading spark plug 19A. Proceed to

  On the other hand, when the determination in step S7 is NO, the process proceeds to step S9, in which the fuel injection timing by the direct injection valve 18 is advanced from the fuel injection timing in the normal control, and the fuel by the pressure regulating valve 75 is increased. The fuel injection amount from the direct injection valve 18 is increased to increase the pressure higher than the fuel pressure in the normal control, and further compensate for the decrease in engine output due to misfire of the trailing side spark plug 19B. Proceed to step S10.

  In step S10, various input signals are newly read to check whether or not the engine request operation is newly performed, and it is determined whether or not the operation request for the engine 10 has been lost. When the determination in step S10 is NO, the process returns to step S5. On the other hand, when the determination in step S10 is YES, the process proceeds to step S11, the engine 10 is stopped, and then the process returns.

  Therefore, in the present embodiment, when misfire of only the leading spark plug 19A is detected, the fuel injection timing by the direct injection valve 18 and the fuel pressure by the pressure regulating valve 75 are reduced to the vicinity of the compression top. In a certain working chamber, an air-fuel mixture can be formed by moving toward the trailing spark plug 19B. In addition, when misfire is detected only in the trailing side ignition plug 19B, the advance of the fuel injection timing by the direct injection valve 18 and the increase in fuel pressure by the pressure regulating valve 75 cause an increase in fuel pressure in the vicinity of the compression top. The air-fuel mixture can be formed by moving toward the leading spark plug 19A. Therefore, even if the leading spark plug 19A or the trailing spark plug 19B misfires, the same combustibility as when the misfire of both the spark plugs 19A and 19B is not detected can be maintained. Can be satisfactorily suppressed. Further, when misfire of only one spark plug is detected by the misfire detection circuits 57A and 57B, a decrease in engine output due to misfire of the one spark plug is caused by an increase in the fuel injection amount from the direct injection valve 18. Since it compensates, the fall of the engine output by the misfire of one spark plug can be suppressed favorably.

(Embodiment 2)
8 and 9 show a second embodiment of the present invention, in which the engine 10 is a reciprocating engine in which a piston reciprocates in a cylinder 135, and the hardware configuration of the vehicle 1 other than the engine 10 is as described above. This is the same as the first embodiment.

  In the present embodiment, the engine 10 includes a cylinder block 131 and a cylinder head 132 mounted thereon, and a plurality of cylinders 135 (cylinders) are formed inside the cylinder block 131 (FIG. 8). And FIG. 9 shows only one).

  A piston 136 is slidably inserted in each cylinder 135, and the piston 136 defines a combustion chamber 137 together with the cylinder 135 and the cylinder head 132. The piston 136 is connected to the crankshaft 139 by a connecting rod 138, and the crankshaft 139 rotates around its central axis in accordance with the reciprocating motion of the piston 136. The plurality of cylinders 135 are arranged in the direction of the central axis of the crankshaft 139.

  The cylinder head 132 is formed with two intake ports 141 for each cylinder, and each of the intake ports 141 communicates with the combustion chamber 137 by opening on the lower surface of the cylinder head 132 (the ceiling of the combustion chamber 137). ing. Also, the cylinder head 132 is formed with two exhaust ports 142 for each cylinder, and each of the exhaust ports 142 opens to the lower surface of the cylinder head 132 (the ceiling of the combustion chamber 137). Communicate. The intake port 141 is connected to the intake passage 14 through which fresh air introduced into the combustion chamber 137 flows. On the other hand, the exhaust port 142 is connected to the exhaust passage 15 through which burned gas (exhaust gas) from the combustion chamber 137 flows.

  Further, the cylinder head 132 is provided with intake valves 145A and 145B capable of shutting off (closing) the two intake ports 141 from the combustion chamber 137, and the two exhaust ports 142 are connected to the combustion chamber 137. Exhaust valves 146A and 146B that can be shut off (closed) are provided. The intake valves 145A and 145B are driven by an intake valve drive mechanism, and the exhaust valves 146A and 146B are driven by an exhaust valve drive mechanism. The intake valves 145A and 145B and the exhaust valves 146A and 146B reciprocate at a predetermined timing to open and close the intake port 141 and the exhaust port 142, respectively, and perform gas exchange in the combustion chamber 137. Although not shown, the intake valve drive mechanism and the exhaust valve drive mechanism each have an intake cam shaft and an exhaust cam shaft that are drivingly connected to the crankshaft 139, and these camshafts are synchronized with the rotation of the crankshaft 139. Then rotate.

  Fuel that directly injects fuel (either gas fuel or liquid fuel) into the combustion chamber 137 on the central axis of the cylinder 135 in the cylinder head 132 (the center of the ceiling of the combustion chamber 137). An injection valve 151 is provided. The tip end portion (fuel injection opening) of the fuel injection valve 151 faces the center portion of the cylinder 135 at the upper end portion in the combustion chamber 137.

  The cylinder head 132 is provided with an intake side spark plug 152A and an exhaust side spark plug 152B for each cylinder. The intake-side ignition plug 152A is disposed between the two intake valves 145A and 145B (that is, the intake side) in the ceiling portion of the combustion chamber 137, and the exhaust-side ignition plug 152B is disposed in the two exhaust valves 146A and 146A, 146B (ie, on the exhaust side). The tip portions (ignition portions) of both the spark plugs 152A and 152B face the combustion chamber 137. In FIG. 6, both spark plugs 152A and 152B are only visible at the front end facing the combustion chamber 137, but for the sake of clarity, the entire spark plugs 152A and 152B are shown as solid lines (the fuel injection valve 151 and the two spark plugs in FIG. 12). The same applies to 152A, 152B, and the fuel injection valve 151 and the peripheral spark plug 155 of FIG. 15). In the present embodiment, the intake-side spark plug 152A and the exhaust-side spark plug 152B are perpendicular to the center axis of the crankshaft 139 passing through the center of the cylinder 135 when viewed from the center axis direction of the cylinder 135 (the left-right direction in FIG. 9). ), Which lies on a straight line passing through the center of the cylinder 135.

  The configuration related to detection of ignition and misfire of the intake side spark plug 152A and the exhaust side spark plug 152B is the same as that of the leading side spark plug 19A and the trailing side spark plug 19B in the first embodiment.

  In the present embodiment, the fuel injection valve 151 injects fuel from the central portion of the cylinder 135 toward the entire circumference thereof as viewed from the central axis direction of the cylinder 135 (the central axis substantially coincides with the central axis of the cylinder 135). Injection mode in which the fuel is injected into the cone), fuel injection mode from the center of the cylinder 135 toward the intake side spark plug 152A, and fuel injection from the center of the cylinder 135 toward the exhaust side spark plug 152B. It is configured to be switchable to the injection mode. Such an injection mode switching configuration is well known (see, for example, JP 2010-37958 A, JP 2007-285204 A, and JP 2000-205088 A). An injection mode in which fuel is injected from the central portion of the cylinder 135 toward the entire circumference thereof when viewed from the central axis direction of the cylinder 135 corresponds to a first injection mode, and is viewed from the central axis direction of the cylinder 135. The injection mode in which the fuel is injected from the center of the cylinder 135 toward the intake side spark plug 152A corresponds to the second injection mode, and the fuel is exhausted from the center of the cylinder 135 when viewed from the central axis direction of the cylinder 135. The injection form injecting toward the side spark plug 152B corresponds to the third injection form.

  During normal control of the engine 10, the control unit 100 injects fuel so that fuel is injected in an injection form in which fuel is injected from the center of the cylinder 135 toward the entire periphery thereof when viewed from the central axis direction of the cylinder 135. The valve 151 is controlled.

  When the misfire of only the intake side spark plug 152A is detected, the control unit 100 injects fuel from the center of the cylinder 135 toward the exhaust side spark plug 152B when viewed from the central axis direction of the cylinder 135. When the fuel injection valve 151 is controlled so as to be injected in the form, and when misfire of only the exhaust side spark plug 152B is detected, fuel is sucked from the center of the cylinder 135 as viewed from the central axis direction of the cylinder 135. The fuel injection valve 151 is controlled so that the fuel is injected in the injection form in which the fuel is injected toward the side spark plug 152A.

  Similarly to the first embodiment, when the misfire of only one of the intake side spark plug 152A and the exhaust side spark plug 152B is detected, the control unit 100 detects the engine due to the misfire of the one spark plug. The decrease in output is compensated by the increase in the fuel injection amount from the fuel injection valve 151.

  Here, the processing operation from the start to the stop of the engine 10 by the control unit 100 in the present embodiment will be described based on the flowchart of FIG.

  In steps S21 to S26, operations similar to those in steps S1 to S6 in the flowchart of FIG. 7 are executed. After step S26, the process proceeds to step S30.

  In step S27 that proceeds when the determination in step S25 is YES, it is determined whether or not misfire of only the intake side spark plug 152A is detected.

  When the determination in step S27 is YES, the process proceeds to step S28, in which fuel is injected from the center of the cylinder 135 toward the exhaust side spark plug 152B as viewed from the central axis direction of the cylinder 135. At the same time, the fuel injection amount from the fuel injection valve 151 is increased in order to compensate for the decrease in engine output due to misfiring of the intake side ignition plug 152A, and then the process proceeds to step S30.

  On the other hand, when the determination in step S27 is NO, the process proceeds to step S29, and the fuel is injected from the center of the cylinder 135 toward the intake side spark plug 152A as viewed from the center axis direction of the cylinder 135. In addition to increasing the fuel injection amount from the fuel injection valve 151 in order to compensate for the decrease in engine output due to misfire of the exhaust side ignition plug 152B, the process proceeds to step S30.

  In step S30, as in step S10 in the flowchart of FIG. 7, it is determined whether or not there is no longer an operation request for the engine 10. If the determination in step S30 is NO, the process returns to step S25. On the other hand, when the determination in step S30 is YES, the process proceeds to step S31 to stop the engine 10 and then return.

  Therefore, in this embodiment, when only the intake side ignition plug 152A misfires, the exhaust side ignition plug 152B of the exhaust side ignition plug 152B is compared with the case where both the intake side and exhaust side ignition plugs 152A and 152B are not misfiring in the combustion chamber. The air-fuel mixture can be easily formed on the side, and when only the exhaust side ignition plug 152B misfires, compared to when both the intake side and exhaust side ignition plugs 152A, 152B are not misfiring in the combustion chamber, An air-fuel mixture can be easily formed on the side of the intake side spark plug 152A. Therefore, even if the intake-side ignition plug 152A or the exhaust-side ignition plug 152B misfires, deterioration of combustibility due to misfire can be satisfactorily suppressed. In addition, a decrease in engine output due to misfire of one of the spark plugs can be satisfactorily suppressed.

(Embodiment 3)
11 and 12 show a third embodiment of the present invention, in which the position of the fuel injection valve 151 of each cylinder in the engine 10 which is a reciprocating engine is different from that in the second embodiment. 10 and the hardware configuration of the vehicle 1 are the same as those of the second embodiment.

  That is, the fuel injection valve 151 of each cylinder is disposed at the peripheral edge on the intake side of the ceiling of the combustion chamber 137 of the engine 10. In the present embodiment, the fuel injection valve 151, the intake side ignition plug 152 </ b> A, and the exhaust side ignition plug 152 </ b> B are perpendicular to the center axis of the crankshaft 139 passing through the center of the cylinder 135 as viewed from the center axis direction of the cylinder 135 ( It is located on a straight line that passes through the center of the cylinder 135 and extends in the left-right direction in FIG. The central axis of the fuel injected from the fuel injection valve 151 substantially coincides with the straight line when viewed from the central axis direction of the cylinder 135.

  Also in the present embodiment, as in the first embodiment, a pressure regulating valve 75 is provided as a fuel pressure adjusting means for adjusting the fuel pressure (fuel pressure) supplied to the fuel injection valve 151.

  When both the intake side and the exhaust side spark plugs 152A, 152B are not detected, the control unit 100 uses the pressure regulating valve 75 to set the fuel pressure from the fuel injection valve 151 to at least the exhaust side spark plug 152B. Use a relatively large pressure to reach. When the misfire of only the intake side ignition plug 152A (the ignition plug closer to the fuel injection valve 151) is detected, the control unit 100 sets the fuel pressure to the intake side and exhaust side ignition plugs 152A, 152B. When the misfire of only the exhaust side spark plug 152B (the spark plug far from the fuel injection valve 151) is detected, only the intake side spark plug 152A is detected. The fuel pressure is reduced compared to when the misfire is detected.

  In addition, when the misfire of only one of the intake side spark plug 152A and the exhaust side spark plug 152B is detected, the control unit 100 detects the decrease in the engine output due to the misfire of the one spark plug as a fuel injection. This is compensated by an increase in the fuel injection amount from the valve 151.

  Here, the processing operation from the start to the stop of the engine 10 by the control unit 100 in the present embodiment will be described based on the flowchart of FIG.

  Steps S41 to S51 of the processing operation in the present embodiment are the same as the processing operation in the second embodiment (the flowchart in FIG. 10) except for steps S48 and S49. Only the processing operation of S49 will be described.

  In step S48, which proceeds when the determination in step S47 is YES, which determines whether or not misfire in only the intake side ignition plug 152A has been detected, the fuel pressure by the pressure regulating valve 75 is detected and misfire in only the exhaust side ignition plug 152B is detected. The fuel injection amount from the fuel injection valve 151 is increased in order to increase the fuel pressure at that time and to compensate for the decrease in engine output due to misfire of the intake side spark plug 152A.

  In step S49, which proceeds when the determination in step S47 is NO, the fuel pressure by the pressure regulating valve 75 is made lower than the fuel pressure when misfire of only the intake side ignition plug 152A is detected, and the exhaust side ignition plug In order to compensate for the decrease in the engine output due to the misfire of 152B, the fuel injection amount from the fuel injection valve 151 is increased.

  Therefore, in the present embodiment, when only misfire of the intake side ignition plug 152A (ignition plug closer to the fuel injection valve 151) is detected, the intake side in the combustion chamber 137 is caused by a relatively large fuel pressure. And the air-fuel mixture can be easily formed on the side of the exhaust side spark plug 152B (the far side of the fuel injection valve 151) compared to when both the exhaust side spark plugs 152A and 152B have not misfired. When only the exhaust side ignition plug 152B is misfired, the intake side and the exhaust side ignition plugs 152A and 152B are not misfired in the combustion chamber 137 due to the decrease in fuel pressure. An air-fuel mixture can be easily formed on the spark plug 152A side. Therefore, even if the intake-side ignition plug 152A or the exhaust-side ignition plug 152B misfires, deterioration of combustibility due to misfire can be satisfactorily suppressed. In addition, a decrease in engine output due to misfire of one of the spark plugs can be satisfactorily suppressed.

  In the third embodiment, the fuel injection valve 151 is disposed at the peripheral edge on the intake side of the ceiling of the combustion chamber 137 of the engine 10, but is disposed at the peripheral edge on the exhaust side of the ceiling. It may be. In this case, the control unit 100 determines the fuel pressure by the pressure regulating valve 75 and the fuel injected from the fuel injection valve 151 at least by the intake side ignition when the misfire of the intake side and exhaust side ignition plugs 152A and 152B is not detected. When a misfire of only the exhaust side spark plug 152B (ignition plug far from the fuel injection valve 151) is detected while the pressure reaches a relatively large pressure that reaches the plug 152A, the fuel pressure is set to the intake side and When the misfire of only the intake side spark plug 152A (the spark plug closer to the fuel injection valve 151) is detected, the misfire of the exhaust side spark plugs 152A and 152B is made substantially the same as when both are not detected. The fuel pressure is reduced as compared to when the misfire of only the intake side ignition plug 152A is detected. It may be set to cormorants.

(Embodiment 4)
FIGS. 14 and 15 show Embodiment 4 of the present invention, and a central spark plug disposed at the center of the ceiling of the combustion chamber 137 as a plurality of spark plugs in each cylinder of the engine 10 that is a reciprocating engine. 154 and two peripheral spark plugs 155 provided at the peripheral part of the ceiling part. In the present embodiment, the fuel injection valve 151 is disposed in the vicinity of the center spark plug 154. The fuel injection valve 151 injects the fuel in a cone shape whose central axis extends along the central axis of the cylinder 135. Other hardware configurations of the engine 10 and the vehicle 1 are the same as those of the second embodiment. The engine 10 may be an engine provided with only one of the two peripheral spark plugs 155.

  In the present embodiment, the center spark plug 154 and the two peripheral spark plugs 155 are located on the center axis of the crankshaft 139 passing through the center of the cylinder 135 when viewed from the center axis direction of the cylinder 135.

  Also in the present embodiment, as in the first and third embodiments, a pressure regulating valve 75 is provided as a fuel pressure adjusting means for adjusting the fuel pressure (fuel pressure) supplied to the fuel injection valve 151.

  In the present embodiment, as shown in FIG. 16, the fuel injection valve 151 increases the penetration of the fuel injected from the fuel injection valve 151 as the fuel pressure increases, and is perpendicular to the central axis of the crankshaft 139. The spray spread angle of the fuel increases when viewed from various directions. However, if the fuel pressure is the same, the spray spread angle decreases as the penetration increases. The fuel pressure in the present embodiment is a fuel pressure that provides a penetration and a spray spread angle such that the fuel reaches the vicinity of the two peripheral spark plugs 155.

  When the misfires of the center spark plug 154 and the peripheral spark plug 155 are not detected, the control unit 100 sets the fuel injection timing by the fuel injection valve 151 before the ignition of the two peripheral spark plugs 155. Is at a relatively advanced time so as to reach the vicinity of the two peripheral spark plugs 155. When the misfire of only the central spark plug 154 is detected, the control unit 100 detects the timing of fuel injection by the fuel injection valve 151 and detects the misfire of the central spark plug 154 and the peripheral spark plug 155. On the other hand, a misfire of only the peripheral spark plug 155 (may be a misfire of one peripheral spark plug 155 or a misfire of two peripheral spark plugs 155), while at substantially the same time as when not. When detected, the timing of fuel injection by the fuel injection valve 151 is retarded compared to when misfire of only the center spark plug 154 is detected.

  Further, when the misfire of only one of the center spark plug 154 and the peripheral spark plug 155 is detected, the control unit 100 detects the decrease in engine output due to the misfire of the one spark plug as a fuel injection. This is compensated by increasing the fuel injection amount from the valve 151.

  Here, the processing operation from the start to the stop of the engine 10 by the control unit 100 in the present embodiment will be described based on the flowchart of FIG.

  Steps S61 to S71 of the processing operation in the present embodiment are the same as the processing operation in the third embodiment (flowchart in FIG. 13) except for steps S67 to S69, and thus steps S67 to S67 that are different from the third embodiment. Only the processing operation of S69 will be described.

  In step S67, it is determined whether or not misfire of only the center spark plug 154 has been detected. If the determination in step S67 is YES, the process proceeds to step S68, while if the determination in step S67 is NO, step S67 is performed. Proceed to S69.

  In step S68 that proceeds when the determination in step S67 is YES, the fuel injection timing by the fuel injection valve 151 is advanced from the fuel injection timing when the misfire of only the peripheral spark plug 155 is detected, and The fuel injection amount from the fuel injection valve 151 is increased in order to compensate for a decrease in engine output due to misfire of the center spark plug 154.

  In step S69 that proceeds when the determination in step S67 is NO, the fuel injection timing by the fuel injection valve 151 is retarded from the fuel injection timing when the misfire of only the center spark plug 154 is detected, The fuel injection amount from the fuel injection valve 151 is increased in order to compensate for the decrease in engine output due to the misfire of the peripheral spark plug 155.

  Note that the control unit 100 detects the fuel by the fuel injection valve 151 when the misfire of only the peripheral spark plug 155 is detected, as compared with the case where the misfire of only the center spark plug 154 is detected as described above. Instead of, or in addition to retarding the injection timing, the fuel pressure by the pressure regulating valve 75 may be reduced as compared to when the misfire of only the center spark plug 154 is detected. In this case, when the misfire of only the center spark plug 154 is detected, the fuel pressure is set to substantially the same pressure as when the misfire of the center spark plug 154 and the peripheral spark plug 155 is not detected.

  Therefore, in this embodiment, when only the center spark plug 154 misfires, the peripheral spark plug in the combustion chamber 137 is compared to when both the center spark plugs 154 and 155 do not misfire. The air-fuel mixture can be easily formed on the side of 155, and when only the peripheral spark plug 155 misfires, the center portion and the combustion chamber 137 are caused by retarding the fuel injection timing and / or lowering of the fuel pressure. Compared to when the peripheral spark plugs 154 and 155 are not misfiring, the air-fuel mixture can be easily formed on the center spark plug 154 side. Therefore, even if the center spark plug 154 or the peripheral spark plug 155 misfires, deterioration of combustibility due to misfire can be satisfactorily suppressed. In addition, a decrease in engine output due to misfire of one of the spark plugs can be satisfactorily suppressed.

  In the fourth embodiment, the fuel injection valve 151 injects the fuel from the position where the fuel injection valve 151 is disposed toward the entire circumference thereof as viewed from the central axis direction of the cylinder 135 (the central axis is the cylinder 135). Injection mode in which the fuel is injected into a cone extending along the central axis of the fuel injection), an injection mode in which fuel is injected from the position where the fuel injection valve 151 is disposed toward one peripheral spark plug 155, and fuel is injected into the fuel injection valve 151. May be configured to be able to be switched to an injection mode for injecting toward the other peripheral spark plug 155. In this case, when the misfire of only one of the two peripheral spark plugs 155 is detected, the control unit 100 injects fuel toward the other peripheral spark plug 155. The fuel injection valve 151 is controlled so as to be injected in the form, and when misfire of only the other peripheral spark plug 155 is detected, the fuel is injected toward the one peripheral spark plug 155. The fuel injection valve 151 can be controlled so as to inject.

  Further, the central spark plug 154 and the two peripheral spark plugs 155 are positioned on a straight line passing through the center of the cylinder 135 and extending in a direction perpendicular to the central axis of the crankshaft 139 when viewed from the central axis direction of the cylinder 135. You may do it. In this case, the fuel injection valve 151 injects fuel from the position where the fuel injection valve 151 is disposed toward the entire periphery thereof as viewed from the direction of the central axis of the cylinder 135 (the central axis is along the central axis of the cylinder 135). Injection mode in which the fuel injection valve 151 is disposed), an injection mode in which fuel is injected from the position where the fuel injection valve 151 is disposed toward the one peripheral spark plug 155, and fuel from the position where the fuel injection valve 151 is disposed. If the control unit 100 is configured so as to be able to switch to an injection mode injecting toward the other peripheral spark plug 155, the control unit 100 misfires only the one peripheral spark plug 155 of the two peripheral spark plugs 155. When the fuel injection valve 151 is detected, the fuel injection valve 151 is controlled so that the fuel is injected in the injection form in which the fuel is injected toward the other peripheral spark plug 155. When the square misfire of only the peripheral portion spark plug 155 is detected, the fuel can be controlled fuel injection valve 151 to inject with the injection mode for injecting toward one of the peripheral edge spark plug 155 described above.

  The present invention is not limited to the embodiment described above, and can be substituted without departing from the spirit of the claims.

  The above-described embodiments are merely examples, and the scope of the present invention should not be interpreted in a limited manner. The scope of the present invention is defined by the scope of the claims, and all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  The present invention relates to a multi-ignition system having a fuel injection valve for injecting fuel, and a plurality of spark plugs for igniting a mixture of fuel and air from the fuel injection valve at a plurality of positions in a combustion chamber. This is useful for a control device of a type engine, and particularly useful when the multi-ignition type engine is an engine of a hybrid vehicle.

10 Multi-ignition engine 18 Direct injection valve (fuel injection valve)
19A Leading side spark plug 19B Trailing side spark plug 57A Leading side spark plug misfire detection circuit (misfire detection means)
57B Misfire detection circuit for trailing side spark plug (misfire detection means)
100 Control unit (control means)
151 Fuel Injection Valve 152A Intake Side Spark Plug 152B Exhaust Side Spark Plug 154 Center Part Spark Plug 155 Peripheral Part Spark Plug

Claims (7)

Control of a multi-ignition engine having a fuel injection valve for injecting fuel and a plurality of spark plugs for igniting a mixture of fuel and air from the fuel injection valve at a plurality of positions in the combustion chamber A device,
Misfire detection means for detecting misfire of each of the spark plugs;
Control means for controlling the operation of the engine including the operation of the fuel injection valve and each spark plug;
When the misfire of only a part of the plurality of spark plugs is detected by the misfire detection means by the control means, the misfire of the plurality of spark plugs is not detected in the combustion chamber. Compared to the above, the fuel injection valve is controlled so that the air-fuel mixture is formed on the side of the spark plug where no misfire is detected, and the decrease in engine output due to misfire of some of the spark plugs is reduced. A control device for a multi-ignition engine, which is configured to compensate by increasing the fuel injection amount from the fuel injection valve. The control device for a multi-ignition engine according to claim 1,
The engine is a rotary piston engine,
The plurality of spark plugs are a leading side spark plug and a trailing side spark plug arranged side by side in the rotational direction of the rotor,
The fuel injection valve is a direct injection valve that directly injects fuel into the combustion chamber of the engine,
The control means compares the misfire of only the leading spark plug with the leading fire plug when the misfire detection means detects no misfire of the leading and trailing spark plugs in the combustion chamber. Thus, the fuel injection by the fuel injection valve is compared to when no misfire is detected in the leading side and trailing side ignition plugs so that the air-fuel mixture is formed on the trailing side ignition plug side. On the other hand, when the misfire of only the trailing side spark plug is detected, the misfire of both the leading side and the trailing side spark plug is not detected in the combustion chamber. The leading side so that the mixture is formed on the leading spark plug side. Than when misfire fine trailing side spark plug has not been detected together, the control apparatus for a multi-ignition engine, characterized in that it is configured to time the advance of the fuel injection by the fuel injection valve. The control device for a multi-ignition engine according to claim 2,
The fuel injection valve is provided such that the fuel injection direction is directed to the rotation direction of the rotor,
A fuel pressure adjusting means for adjusting a fuel pressure supplied to the fuel injection valve;
The control means further controls the operation of the fuel pressure adjusting means. When the misfire detection means detects a misfire of only the leading spark plug, the misfire of the leading and trailing spark plugs is detected. Compared to when both are not detected, the fuel pressure by the fuel pressure adjusting means is reduced. On the other hand, when only the trailing-side spark plug is misfired, the leading-side and trailing-side spark plugs are misfired. A control device for a multi-ignition engine, characterized in that the fuel pressure by the fuel pressure adjusting means is increased as compared to when both are not detected. The control device for a multi-ignition engine according to claim 1,
The engine is a reciprocating engine in which a piston reciprocates in a cylinder.
The plurality of spark plugs are an intake side spark plug disposed on the intake side of the ceiling portion of the combustion chamber, and an exhaust side spark plug disposed on the exhaust side of the ceiling portion,
The fuel injection valve is disposed at the center of the ceiling of the combustion chamber and injects at least the fuel from the center of the cylinder toward the entire periphery thereof when viewed from the central axis direction of the cylinder. A first injection mode, a second injection mode in which the fuel is injected from the center of the cylinder toward the intake side spark plug, and a fuel is injected from the center of the cylinder toward the exhaust side spark plug. It is configured to be switchable to the third injection form,
The control means controls the fuel injection valve so that the fuel is injected in the first injection mode when the misfire detection means does not detect misfire of the intake side and exhaust side ignition plugs. On the other hand, when the misfire detection means detects a misfire of only the exhaust side ignition plug, the fuel injection valve is controlled so that the fuel is injected in the second injection mode, and the intake side ignition plug is controlled. A control apparatus for a multi-ignition engine, wherein the fuel injection valve is controlled so that the fuel is injected in the third injection mode when only misfire is detected. The control device for a multi-ignition engine according to claim 1,
The engine is a reciprocating engine in which a piston reciprocates in a cylinder.
The plurality of spark plugs are an intake side spark plug disposed on the intake side of the ceiling portion of the combustion chamber, and an exhaust side spark plug disposed on the exhaust side of the ceiling portion,
The fuel injection valve is disposed at a peripheral portion on the intake side or exhaust side of the ceiling portion of the combustion chamber,
A fuel pressure adjusting means for adjusting a fuel pressure supplied to the fuel injection valve;
The control means further controls the operation of the fuel pressure adjusting means, and when the misfire detection means detects a misfire of only a spark plug far from the fuel injection valve, the fuel injection control means. A control device for a multi-ignition engine, characterized in that the fuel pressure is reduced by the fuel pressure adjusting means compared to when a misfire of only a spark plug closer to the valve is detected. The control device for a multi-ignition engine according to claim 1,
The engine is a reciprocating engine in which a piston reciprocates in a cylinder.
The plurality of spark plugs are a center spark plug disposed at the center of the ceiling of the combustion chamber, and a peripheral spark plug disposed at a peripheral edge of the ceiling,
The fuel injection valve is disposed in the vicinity of the central spark plug,
When the misfire of only the peripheral spark plug is detected by the misfire detection means, the control means detects the timing of fuel injection by the fuel injection valve as compared to when the misfire of only the center spark plug is detected. A control device for a multi-ignition engine characterized by being configured to retard the angle. The control device for a multi-ignition engine according to claim 1,
The engine is a reciprocating engine in which a piston reciprocates in a cylinder.
The plurality of spark plugs are a center spark plug disposed at the center of the ceiling of the combustion chamber, and a peripheral spark plug disposed at a peripheral edge of the ceiling,
The fuel injection valve is disposed in the vicinity of the central spark plug,
A fuel pressure adjusting means for adjusting a fuel pressure supplied to the fuel injection valve;
The control means further controls the operation of the fuel pressure adjusting means. When the misfire detection means detects the misfire of only the peripheral spark plug, the misfire of only the center spark plug is detected. A control device for a multi-ignition engine, wherein the fuel pressure is reduced by the fuel pressure adjusting means.

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