JP2022147537A - internal combustion engine for vehicle - Google Patents

Abstract

To efficiently suppress a misfire in a cylinder while suppressing the size enlargement of an internal combustion engine for a vehicle, and to efficiently suppress the lowering of the drive efficiency of the internal combustion engine.SOLUTION: An internal combustion engine for a vehicle of this invention has three or more cylinders which are aligned in a longitudinal direction. The cylinders have main combustion chambers and sub-chambers, and the three or more cylinders are composed of two outside cylinders arranged at both outer sides in the longitudinal direction, and one or more inside cylinders located between the two outside cylinders in the longitudinal direction. The internal combustion engine also has sub-chamber ignitors which are arranged in the sub-chambers in the two outside cylinders, and the sub-chambers in one or more inside cylinders, and main chamber ignitors arranged in the main combustion chambers of the two outside cylinders.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle internal combustion engine having three or more longitudinally aligned cylinders, each cylinder having a main combustion chamber and an auxiliary chamber communicating with the main combustion chamber through a communication hole.

In a vehicle internal combustion engine such as an automobile engine, the combustion chamber in each of three or more cylinders arranged in the longitudinal direction is divided into a main combustion chamber and an auxiliary chamber communicating with the main combustion chamber through a communication hole. There is something. In such a cylinder, a spark plug ignites the air-fuel mixture in the pre-combustion chamber, and the combustion of the air-fuel mixture in the pre-combustion chamber creates a torch-shaped flame (jet flame) that travels from the pre-combustion chamber through the communication hole to the main combustion chamber. This jet flame can burn the air-fuel mixture in the main combustion chamber. Such an internal combustion engine is sometimes called a pre-chamber internal combustion engine. Furthermore, in an internal combustion engine for a vehicle, in order to improve the fuel efficiency of the vehicle, it is possible to deactivate one of a plurality of cylinders according to the operating conditions of the vehicle, for example, the number of rotations of the internal combustion engine, the load factor, and the like. be.

As an example of the internal combustion engine for a vehicle, in order to suppress the temperature rise of the auxiliary fuel injection valve that injects fuel into the auxiliary chamber and the accompanying deposit formation, the engine is stopped according to the load operating range of the auxiliary chamber type engine. A pre-chamber engine configured to change the number of cylinders and configured to decrease the number of idle cylinders as the load operating region is in the low-load operating region and the output torque of the pre-chamber engine is smaller. is mentioned. (For example, see Patent Document 1.)

JP 2018-178719 A

However, in the example of the vehicle internal combustion engine described above, the atomization of the fuel in the cylinder is not promoted when the internal combustion engine is cold-started. In a state where the load operating range of the internal combustion engine is in the low load operating range, gas flow within the cylinder may be stagnant. In these cases, gas remaining in the pre-combustion chamber without being discharged after combustion, i.e., residual gas in the pre-combustion chamber, may cause misfiring as the jet flame that travels from the pre-combustion chamber through the communication hole to the main combustion chamber disappears. There is

Such a misfire may reduce the driving efficiency of the internal combustion engine. Therefore, it is necessary to take measures to prevent misfires, and in taking these measures, it is also important to prevent an increase in the size of the internal combustion engine.

In view of such circumstances, it is desirable to efficiently suppress misfires in the cylinders of internal combustion engines for vehicles while suppressing an increase in the size of the internal combustion engine. Efficient suppression is desired.

To solve the problem, a vehicle internal combustion engine according to one aspect includes three or more cylinders arranged in a longitudinal direction, and each cylinder communicates with a main combustion chamber via a communication hole. a pre-chamber, wherein the three or more cylinders are two outer cylinders arranged on both outer sides in the longitudinal direction, and one or more cylinders positioned between the two outer cylinders in the longitudinal direction. a pre-chamber igniter disposed in each of the pre-chambers of the two outer cylinders and the pre-chambers of the one or more inner cylinders; and the two outer cylinders. and a main combustion chamber igniter located in each of the main combustion chambers in the cylinder.

In the internal combustion engine for a vehicle according to one aspect, it is possible to efficiently suppress misfires in the cylinders while suppressing an increase in the size of the internal combustion engine, and thus to efficiently suppress a decrease in drive efficiency of the internal combustion engine.

FIG. 1 is a configuration diagram schematically showing a vehicle internal combustion engine according to one embodiment. FIG. 2 is a vertical cross-sectional view that schematically shows a main combustion chamber, a pre-chamber, and their peripheral portions of an outer cylinder of an internal combustion engine for a vehicle according to one embodiment, cut along the central axis thereof. 3 is a cross-sectional view taken along the line XX of FIG. 2. FIG. FIG. 4 is a vertical cross-sectional view schematically showing a main combustion chamber, a pre-chamber, and peripheral portions thereof of an inner cylinder of an internal combustion engine for a vehicle according to one embodiment, cut along the central axis thereof. 5 is a cross-sectional view taken along the line YY of FIG. 4. FIG. FIG. 6 is a map used to determine the load state of the internal combustion engine based on the load factor of the internal combustion engine and the rotational speed of the internal combustion engine. FIG. 7 is a flowchart for explaining an example of a control method for a vehicle internal combustion engine according to one embodiment.

A vehicle internal combustion engine according to one embodiment will be described. An internal combustion engine for a vehicle according to the present embodiment (hereinafter simply referred to as an "internal combustion engine" as necessary) is an engine mounted on a vehicle. However, the vehicle internal combustion engine may be an internal combustion engine such as an engine mounted on a vehicle other than an automobile.

"Overview of Vehicle Internal Combustion Engine"
An outline of a vehicle internal combustion engine 1 according to the present embodiment will be described with reference to FIGS. 1 to 5. FIG. That is, the vehicle internal combustion engine 1 according to the present embodiment is schematically configured as follows. As shown in FIG. 1, a vehicle internal combustion engine 1 has four cylinders 10, 20 arranged along its longitudinal direction (indicated by a double-sided arrow L).

1-5, each cylinder 10,20 has a main combustion chamber 11,21. Each cylinder 10,20 also has an auxiliary chamber 12,22 which communicates with its main combustion chamber 11,21 through a communication hole 13,23. As shown in FIG. 1 , the four cylinders 10 and 20 are composed of two outer cylinders 10 arranged on both longitudinally outer sides and two inner cylinders longitudinally positioned between the two outer cylinders 10 . Cylinder 20.

However, the internal combustion engine can also be constructed with more than two cylinders along its length. In this case, the three or more cylinders can consist of two outer cylinders and one or more inner cylinders.

Referring to FIGS. 2-5, the internal combustion engine 1 has a pre-chamber igniter 14 located in the pre-chamber 12 of each outer cylinder 10 . The internal combustion engine 1 has a main combustion chamber igniter 15 arranged in the main combustion chamber 11 of each outer cylinder 10 . The internal combustion engine 1 has a pre-chamber igniter 24 arranged in the pre-chamber 22 of each inner cylinder 20 .

Further, the vehicle internal combustion engine 1 according to the present embodiment can be schematically configured as follows. As shown in FIG. 1, an internal combustion engine 1 has a control device 2 configured to make its drive power adjustable. The internal combustion engine 1 includes an exhaust gas recirculation device (hereinafter referred to as an "EGR device" as necessary) 3 configured to allow exhaust gas from the two outer cylinders 10 to be recirculated to the two inner cylinders 20. have

When the internal combustion engine 1 is not warmed up, the control device 2 performs control such that the main combustion chamber igniter 15 in each outer cylinder 10 ignites so that combustion is performed in each outer cylinder 10, and this The EGR device 3 is controlled so that the exhaust gas emitted by combustion in the outer cylinders 10 is recirculated to the inner cylinders 20 . Note that the control device 2 can prohibit the fuel supply (fuel injection) of the injector 29 in each inner cylinder 20 when the internal combustion engine 1 is not warmed up, and the auxiliary chamber igniter 24 in each inner cylinder 20 ignition can be prohibited.

When the internal combustion engine 1 is in a low load state, the control device 2 performs control to prohibit ignition of the pre-chamber igniter 24 in each inner cylinder 20 so as to put each inner cylinder 20 in a resting state, and controls each outer cylinder. In order to bring the cylinder 10 into operation, the ignition of the main combustion chamber igniter 15 in the outer cylinder 10 is followed by the ignition of the pre-combustion chamber igniter 14, thereby driving the internal combustion engine 1. It has become. The low load state is a state in which the internal combustion engine 1 is driven such that the load factor (%) is less than the first load factor threshold E1.

The control device 2 prohibits the ignition of the main combustion chamber igniter 15 and the auxiliary chamber igniter 14 in each outer cylinder 10 so as to put each outer cylinder 10 in a resting state when the internal combustion engine 1 is in a medium load state. , and to ignite the pre-combustion chamber igniter 24 in each inner cylinder 20 so as to bring the inner cylinder 20 into operation, thereby driving the internal combustion engine 1 . Note that the medium load state is a state in which the internal combustion engine 1 is driven such that the load factor is equal to or greater than the first load factor threshold E1 and less than the second load factor threshold E2. The second load factor threshold E2 is greater than the first load factor threshold E1.

"Details of Internal Combustion Engines for Vehicles"
Referring to FIGS. 1 to 6, the vehicle internal combustion engine 1 according to the present embodiment can be configured in detail as follows. As shown in FIG. 1, the internal combustion engine 1 has a water temperature detector 4 configured to detect the water temperature (° C.) of its cooling water. The internal combustion engine 1 has an accelerator opening detector 5 configured to detect an accelerator opening (%).

The internal combustion engine 1 has a rotational speed detector 6 configured to detect its rotational speed (s ⁻¹ ). For example, the rotational speed detector 6 can be a crank angle sensor. However, the rotational speed detector is not limited to the crank angle sensor.

As shown in FIG. 1, the four cylinders 10, 20 are arranged substantially in series along a longitudinal axis 1a extending in the longitudinal direction. That is, the internal combustion engine 1 is of a serial type. However, the internal combustion engine may be V-shaped, horizontally opposed, or the like, as long as it is configured to have three or more cylinders arranged longitudinally.

2-5, each cylinder 10, 20 has a piston 16, 26 configured to reciprocate within the cylinder 10, 20 along a central axis 10a, 20a. The main combustion chambers 11 and 21 of each cylinder 10 and 20 are surrounded by bore walls 10b and 20b, cylinder heads 10c and 20c, and pistons 16 and 26 of the cylinders 10 and 20, respectively. The auxiliary chambers 12, 22 of the cylinders 10, 20 are arranged on the central axes 10a, 20a of the cylinders 10, 20 at the cylinder heads 10c, 20c of the cylinders 10, 20, respectively.

Each cylinder 10, 20 has two intake ports 10d, 20d provided in the cylinder heads 10c, 20c of the cylinders 10, 20, and these two intake ports 10d, 20d are configured to be openable and closable. It has two intake valves 17,27. Each cylinder 10, 20 is also configured such that two intake ports 10d, 20d provided in the cylinder heads 10c, 20c of the cylinders 10, 20 and these two intake ports 10d, 20d can be opened and closed, respectively. It has two exhaust valves 18,28.

However, each cylinder may have one or more intakes and one or more intake valves configured to allow such one or more intakes to open and close. Each cylinder may also have one or more exhaust ports and one or more exhaust valves configured to allow such one or more exhaust ports to open and close.

Further, the intake ports 10d and 20d of the cylinders 10 and 20 are located on one side of the cylinders 10 and 20 in the radial direction ( It is hereinafter referred to as an "intake side" as required). Each exhaust port 10e, 20e of each cylinder 10, 20 is located on the other radial side of the cylinder 10, 20 with respect to the longitudinal axis 1a of the internal combustion engine 1 and the center axis 10a, 20a of the cylinder 10, 20 (hereinafter referred to as optionally on the "exhaust side").

2 and 3, the main combustion chamber igniter 15 of each outer cylinder 10 is arranged in the main combustion chamber 11 of this outer cylinder 10 between each intake port 10d, 20d and each exhaust port 10e, 20e. placed in A main combustion chamber igniter 15 for each outer cylinder 10 is arranged on the longitudinal axis 1 a of the internal combustion engine 1 . The main combustion chamber igniter 15 of each outer cylinder 10 is arranged on the outer side in the longitudinal direction of the internal combustion engine 1 with respect to the center axes 10a and 20a of the cylinders 10 and 20. As shown in FIG.

As shown in FIGS. 4 and 5, the main combustion chamber 21 of each inner cylinder 20 is not provided with an igniter, ie, a main combustion chamber igniter. As shown in FIG. 1, each cylinder 10,20 has an injector 19,29 configured to enable fuel to be supplied to its primary combustion chamber 11,21 and its secondary chamber 12,22. Each cylinder 10, 20 has two injectors 19, 29 arranged to allow fuel to be supplied from its two intakes 10d, 20d respectively to its main combustion chamber 11, 21 and its auxiliary chambers 12, 22. have

As shown in FIG. 1, the internal combustion engine 1 has an intake manifold 7 that is connected to the intake ports 10d and 20d of the cylinders 10 and 20, respectively. The internal combustion engine 1 has an exhaust manifold 8 connected to exhaust ports 10e and 20e of the cylinders 10 and 20, respectively. However, the internal combustion engine can also have a collective exhaust pipe instead of an exhaust manifold.

The EGR device 3 connects an outer pipe 8a of an exhaust manifold 8 connected to each exhaust port 10e of each outer cylinder 10 and an inner pipe 7a of an intake manifold 7 connected to each intake port 20d of each inner cylinder 20. It has a circulation pipe 3a. The EGR device 3 is capable of opening and shutting off the flow of exhaust gas (indicated by a one-sided arrow G) passing through the circulation pipe 3a from each exhaust port 10e of each outer cylinder 10 toward each intake port 20d of each inner cylinder 20. It has an exhaust gas recirculation valve (hereinafter referred to as "EGR valve" as necessary) 3b configured to be openable and closable.

In the idle state of each cylinder 10, 20, all intake valves 17, 27 close all intake ports 10d, 20d, respectively, all exhaust valves 18, 28 close all exhaust ports 10e, 20e, respectively, and injector 19 , 29 stop supplying fuel, and no combustion takes place in the main combustion chambers 11, 21 and the auxiliary chambers 12, 22.

"Control device details"
Referring to FIG. 1, the control device 2 can be configured in detail as follows. The control device 2 includes electronic components such as a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), flash memory, input interface, output interface, etc., and an electric circuit in which these electronic components are arranged. configured to contain The ROM stores programs for exerting the functions of the control device 2 together with various control constants, various maps, and the like. Therefore, the functions of the control device 2 can be exhibited when the CPU executes the program stored in the ROM. However, the control device is not limited to this.

The control device 2 is configured to be able to control opening and closing of the EGR valve 3b of the EGR device 3 . The control device 2 determines that the internal combustion engine 1 is in a warm-up state when the water temperature detection value T detected by the water temperature detection unit 4 is equal to or greater than a predetermined water temperature threshold value T1, and the water temperature detection value T is It is configured to determine that the internal combustion engine 1 is not in a warm-up state when the water temperature is less than a predetermined water temperature threshold value T1.

Furthermore, the control device 2 can prohibit the ignition of the pre-chamber igniter 14 of each outer cylinder 10 and the ignition of the pre-chamber igniter 24 of each inner cylinder 20 when the internal combustion engine 1 is not warmed up. can be prohibited. The control device 2 is configured to open an EGR valve 3b of the EGR device 3 when the internal combustion engine 1 is not warmed up, and to close the EGR valve 3b when the internal combustion engine 1 is warmed up.

The control device 2 adjusts the load of the internal combustion engine 1 based on at least the accelerator opening detection value A detected by the accelerator opening detector 5 and the rotational speed detection value R detected by the rotational speed detector 6. It is configured so that the rate can be calculated. Referring particularly to FIG. 6, the control device 2 can determine that the internal combustion engine 1 is in the low load state at least when the calculated value E of the load factor is less than the first load factor threshold E1. In FIG. 6, the horizontal axis R indicates the detected rotational speed value R(s ⁻¹ ), and the vertical axis E indicates the calculated value E (%) of the load factor.

Furthermore, in FIG. 6, the low load state is a state within the low load region indicated by the hatched area P1. In particular, when the calculated value E of the load factor is less than the first load factor threshold E1 and the detected value R of the rotational speed is less than the first rotational speed threshold R1, the control device 2 determines that the internal combustion engine 1 is under low load. state can be determined.

The control device 2 can determine that the internal combustion engine 1 is in the medium load state at least when the calculated value E of the load factor is equal to or greater than the first load factor threshold E1 and less than the second load factor threshold E2. . In FIG. 6, the medium load state is a state within the medium load region indicated by the hatched area P2. In particular, the control device 2 operates when the calculated value E of the load factor is greater than or equal to the first load factor threshold E1 and less than the second load factor threshold E2, and the detected value R of the rotational speed is greater than or equal to the first rotational speed threshold R1. It can be determined that the internal combustion engine 1 is in the medium load state when the rotational speed is present and less than the second rotational speed threshold value R2. The second rotational speed threshold R2 is higher than the first rotational speed threshold R1.

The control device 2 can determine that the internal combustion engine 1 is in the high load state at least when the calculated value E of the load factor is equal to or greater than the second load factor threshold value E2. In FIG. 6, the high load state is a state within the high load region indicated by the hatched area P3. In particular, when the calculated value E of the load factor is equal to or greater than the second load factor threshold E2 and the detected value R of the rotational speed is equal to or greater than the second rotational speed threshold R2, the control device 2 determines that the internal combustion engine 1 is under a high load. state can be determined.

The control device 2 is configured to ignite the auxiliary chamber igniters 14, 24 of all the cylinders 10, 20 to put all the cylinders 10, 20 into operation when the internal combustion engine 1 is in a high load state. . At this time, the control device 2 can prohibit ignition of the main combustion chamber igniter 15 of each outer cylinder 10 . However, the controller may also effect ignition of the main combustion chamber igniter of each outer cylinder when the internal combustion engine is under high load conditions.

1 to 5, when each outer cylinder 10 is in a resting state, the control device 2 causes all intake valves 17 to close all intake ports 10d, all exhaust valves 18 to close all exhaust ports 10e, and injectors to 19 can control the internal combustion engine 1 to stop the supply of fuel, inhibit ignition of the pre-chamber igniter 14 and inhibit ignition of the main combustion chamber igniter 15 . In the resting state of each inner cylinder 20, the control device 2 causes all intake valves 27 to close all intake ports 20d, all exhaust valves 28 to close all exhaust ports 20e, injectors 29 to stop supplying fuel, In addition, the internal combustion engine 1 can be controlled so as to prohibit ignition of the pre-combustion chamber igniter 24 .

"Method for Controlling Vehicle Internal Combustion Engine"
An example of a control method for the vehicle internal combustion engine 1 according to the present embodiment will be described with reference to FIG. First, the internal combustion engine 1 is started by, for example, switching an ignition switch (not shown) of the vehicle from an off state to an on state (step S1).

It is determined whether or not the internal combustion engine 1 is warmed up (step S2). If the internal combustion engine 1 is not warmed up (NO), the main combustion chamber igniter 15 is ignited in each outer cylinder 10 to perform combustion in that outer cylinder 10, and the pre-combustion chamber ignition of each outer cylinder 10 is performed. EGR valve 3b for inhibiting ignition of unit 14, inhibiting ignition of pre-chamber igniter 24 of each inner cylinder 20, and recirculating exhaust gas discharged by combustion of each outer cylinder 10 to each inner cylinder 20 is opened (step S3). Return to step S2 again. When the internal combustion engine 1 is not warmed up, the fuel supply (fuel injection) of the injectors 29 in the inner cylinders 20 can be prohibited, and the ignition of the auxiliary chamber igniters 24 in the inner cylinders 20 can be prohibited. be able to.

If the internal combustion engine 1 is warmed up at step S2 (YES), the EGR valve 3b is closed (step S4). It is determined whether or not the internal combustion engine 1 is in a low load state (step S5). If the internal combustion engine 1 is in a low load state (YES), the ignition of the pre-chamber igniter 24 in each inner cylinder 20 is prohibited so that each inner cylinder 20 is put into a resting state, and each outer cylinder 10 is put into an operating state. Therefore, following ignition of the main combustion chamber igniter 15 in the outer cylinder 10, ignition of the pre-combustion chamber igniter 14 is performed (step S6).

It is determined whether or not the internal combustion engine 1 has stopped by switching an ignition switch (not shown) of the vehicle from an on state to an off state (step S7). If the internal combustion engine 1 has not stopped (NO), the process returns to step S5. If the internal combustion engine 1 has stopped (YES), the control of the internal combustion engine 1 ends.

If the internal combustion engine 1 is not in the low load state at step S5 (NO), it is determined whether the internal combustion engine 1 is in the middle load state (step S8). If the internal combustion engine 1 is in a medium load state (YES), the ignition of the main combustion chamber igniter 15 and the pre-combustion chamber igniter 14 in each outer cylinder 10 is prohibited so as to put the outer cylinder 10 in a resting state, and each inner cylinder The auxiliary chamber igniter 24 in the inner cylinder 20 is ignited in order to bring the cylinder 20 into operation (step S9).

It is determined whether or not the internal combustion engine 1 has stopped by switching an ignition switch (not shown) of the vehicle from an on state to an off state (step S7). If the internal combustion engine 1 has not stopped (NO), the process returns to step S5. If the internal combustion engine 1 has stopped (YES), the control of the internal combustion engine 1 ends.

In step S8, if the internal combustion engine 1 is not in the middle load state (NO), the internal combustion engine 1 is in the high load state (step S10). The auxiliary chamber igniters 14, 24 of all the cylinders 10, 20 are ignited so that all the cylinders 10, 20 are brought into operation (step S11).

It is determined whether or not the internal combustion engine 1 has stopped by switching an ignition switch (not shown) of the vehicle from an on state to an off state (step S7). If the internal combustion engine 1 has not stopped (NO), the process returns to step S5. If the internal combustion engine 1 has stopped (YES), the control of the internal combustion engine 1 ends.

As described above, the vehicle internal combustion engine 1 according to the present embodiment includes three or more cylinders 10 and 20 arranged in the longitudinal direction, and each cylinder 10 and 20 defines the main combustion chambers 11 and 21 and the communication holes 13 and 23. The three or more cylinders 10 and 20 are two outer cylinders 10 respectively arranged on both sides of the longitudinal direction. and one or more inner cylinders 20 positioned between the two outer cylinders 10 in the longitudinal direction. Pre-combustion chamber igniters 14 and 24 arranged in each of the pre-chambers 22 of the two or more inner cylinders 20, and main combustion chamber igniters 15 arranged in each of the main combustion chambers 11 of the two outer cylinders 10 I have.

In such an internal combustion engine 1, even if a misfire occurs because the air-fuel mixture in the pre-combustion chamber 12 cannot be combusted by the ignition of the pre-combustion chamber igniter 14 in the outer cylinder 10, the main combustion chamber igniter 15 The air-fuel mixture in the main combustion chamber 11 can be combusted by the ignition of . Further, since the dead space around the outer cylinder 10 is larger than the dead space around the inner cylinder 20, the dead space around the outer cylinder 10 and its surroundings is designed to suppress the enlargement of the internal combustion engine 1. Components associated with vessel 15 can be installed. Therefore, misfires in the cylinders 10 and 20 can be efficiently suppressed while suppressing an increase in the size of the internal combustion engine 1, and a decrease in driving efficiency of the internal combustion engine 1 can be effectively suppressed.

A vehicle internal combustion engine 1 according to this embodiment includes a control device 2 configured to be able to adjust the driving force of the vehicle internal combustion engine 1, The exhaust gas recirculation device 3 configured to be recirculated to the inner cylinders 20 is provided, and the control device 2 controls combustion in the outer cylinders 10 when the internal combustion engine 1 is not warmed up. and control the ignition of the main combustion chamber igniter 15 of that outer cylinder 10 to implement Therefore, the exhaust gas recirculation device 3 is controlled.

In such an internal combustion engine 1, even if a misfire occurs because the air-fuel mixture in the pre-chamber 12 cannot be combusted by the ignition of the pre-chamber igniter 14 in the outer cylinder 10, particularly at cold start. , the ignition of the main combustion chamber igniter 15 allows the mixture in the main combustion chamber 11 to be combusted. In addition to this, such gas after combustion in the outer cylinder 10 is recirculated to the inner cylinder 20, whereby the inner cylinder 20 can be warmed up. Therefore, it is possible to efficiently suppress misfires in the cylinders 10 and 20 while suppressing an increase in the size of the internal combustion engine 1 , thereby efficiently suppressing a decrease in driving efficiency of the internal combustion engine 1 .

In the vehicle internal combustion engine 1 according to the present embodiment, when the vehicle internal combustion engine 1 is in a low load state in which the load factor of the vehicle internal combustion engine 1 is driven to be less than the first load factor threshold value E1, , control to inhibit ignition of the pre-chamber igniter 24 in each of the one or more inner cylinders 20 so as to put each of the one or more inner cylinders 20 in a resting state, and put each of the two outer cylinders 10 in an operating state. Therefore, the ignition of the main combustion chamber igniter 15 in the outer cylinder 10 is followed by the ignition of the auxiliary chamber igniter 14, thereby driving the vehicle internal combustion engine 1. there is

Generally, in a cylinder of an internal combustion engine, the combustion chamber is compressed when the piston rises during the compression stroke, thereby discharging residual gas in the pre-chamber. In particular, when the internal combustion engine is in a low-load state, the ignition timing of the igniter is before the top dead center of the piston.

On the other hand, in the internal combustion engine 1 for a vehicle according to the present embodiment, when the internal combustion engine 1 is in a low load state, the pre-combustion chamber igniter 14 is ignited in the outer cylinder 10 following the ignition of the main combustion chamber igniter 15 . ignition. Therefore, before the ignition of the pre-combustion chamber igniter 14, the residual gas in the pre-combustion chamber 12 is scavenged by the combustion of the air-fuel mixture in the main combustion chamber 11, so that the air-fuel mixture in the pre-combustion chamber 12 can be reliably burned. . That is, misfires in the auxiliary chamber 12 of the outer cylinder 10 can be efficiently suppressed.

In addition, in the vehicle internal combustion engine 1 according to the present embodiment, when the internal combustion engine 1 is in a low load state, the inner cylinder 20 can be put into the rest state so as to include the rest of the valve drive. In addition, the temperature drop of the bore wall 20b of the inner cylinder 20 can be suppressed. As a result, the inner cylinder 20 can be efficiently operated even immediately after the internal combustion engine 1 shifts from the low load state to the middle or higher load state. Therefore, the decrease in driving efficiency of the internal combustion engine 1 can be efficiently suppressed.

In the vehicle internal combustion engine 1 according to the present embodiment, the control device 2 sets the load factor of the vehicle internal combustion engine 1 to the first load factor threshold value E1 or more, and sets the load factor to the first load factor threshold E1 or higher. The main combustion chamber igniter in each of the two outer cylinders 10 is activated to deactivate each of the two outer cylinders 10 when the engine is in a medium load state that is driven to be less than a second load factor threshold E2 that is greater than the threshold E1. 15 and the pre-chamber igniter 14 to inhibit ignition, and to perform ignition of the pre-chamber igniter 24 in each of the one or more inner cylinders 20 to bring that inner cylinder 20 into operation. , thereby driving the internal combustion engine 1 for a vehicle.

In such an internal combustion engine 1, when the internal combustion engine 1 is in a medium load state, the outer cylinder 10 is put into a resting state while the inner cylinder 20 is kept operating, so a main combustion chamber igniter is not provided. The internal temperature of the inner cylinder 20 and the temperature of the bore wall 20b of the inner cylinder 20 can be maintained at high temperatures to prevent misfires. In particular, when the internal combustion engine 1 shifts from a low load state to a medium load state, the internal temperature of the inner cylinder 20 and the temperature of the bore wall 20b of the inner cylinder 20 tend to become high enough to prevent misfiring. Even if the load state of engine 1 changes, misfires in the inner cylinder 20 can be efficiently suppressed.

Although the embodiments of the present invention have been described so far, the present invention is not limited to the above-described embodiments, and the present invention can be modified and changed based on its technical ideas.

DESCRIPTION OF SYMBOLS 1... Vehicle internal combustion engine, internal combustion engine 2... Control device 3... Exhaust gas recirculation device, EGR device 10... Cylinder, outer cylinder, 11... Main combustion chamber, 12... Pre-chamber, 13... Communication hole, 14... Pre-chamber Ignitor 15 Main combustion chamber igniter 20 Cylinder, inner cylinder 21 Main combustion chamber 22 Sub chamber 23 Communication hole 24 Sub chamber igniter E1 First load factor threshold E2 Second 2 load factor threshold

Claims (4)

Equipped with three or more cylinders lined up in the longitudinal direction,
Each cylinder has a main combustion chamber and an auxiliary chamber communicating with the main combustion chamber through a communication hole,
The three or more cylinders consist of two outer cylinders arranged on both outer sides in the longitudinal direction, and one or more inner cylinders positioned between the two outer cylinders in the longitudinal direction, An internal combustion engine for a vehicle,
a pre-chamber igniter arranged in each of the pre-chambers of the two outer cylinders and the pre-chambers of the one or more inner cylinders;
a main combustion chamber igniter located in each of the main combustion chambers of the two outer cylinders. a control device configured to adjust the driving force of the vehicle internal combustion engine;
an exhaust gas recirculation device configured to allow exhaust gas from the two outer cylinders to recirculate to the one or more inner cylinders;
The control device controls ignition of a main combustion chamber igniter of each outer cylinder so that combustion is performed in each outer cylinder when the internal combustion engine is not warmed up, and 2. The vehicle internal combustion engine of claim 1, adapted to control said exhaust gas recirculation device to recirculate exhaust gases emitted by combustion to said one or more inner cylinders. A control device configured to adjust the driving force of the vehicle internal combustion engine,
The control device places each of the one or more inner cylinders in a resting state when the vehicle internal combustion engine is in a low load state in which the load factor is driven to be less than a first load factor threshold. Controlling to inhibit ignition of the pre-combustion chamber igniter in the inner cylinder, and igniting the pre-combustion chamber following the ignition of the main combustion chamber igniter in the outer cylinder in order to put each of the two outer cylinders into operation. 3. A vehicle internal combustion engine according to claim 1 or 2, adapted to control ignition of a device, thereby driving the vehicle internal combustion engine. The control device drives the vehicle internal combustion engine so that the load factor thereof is equal to or higher than the first load factor threshold and the load factor is lower than the second load factor threshold, which is greater than the first load factor threshold. controlling to inhibit ignition of a main combustion chamber igniter and a pre-combustion chamber igniter in each of the two outer cylinders so as to bring each of the two outer cylinders into a resting state when the engine is in a medium load state; each of the inner cylinders is controlled to perform ignition of the pre-chamber igniter in the inner cylinder so as to bring the inner cylinder into an operating state, thereby driving the vehicle internal combustion engine. An internal combustion engine for the described vehicle.

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