Internal combustion engine control device

Abstract

This internal combustion engine control device (14) comprises: an opening degree control unit (60) that, on the basis of the operation amount of an operation member (54) provided in a vehicle (10), controls the opening degree of a throttle valve (40a) of an internal combustion engine (12) provided in the vehicle; an opening degree detection unit (62) that detects the opening degree at a predetermined timing before an intake stroke is started; and an injection amount determination unit (64) that determines a fuel injection amount on the basis of the opening degree detected by the opening degree detection unit. The opening degree control unit can execute opening degree change restriction control for temporarily restricting changes in the opening degree based on changes in the operation amount within a period until the intake stroke is completed.

Description

Internal Combustion Engine Control Device

[0001] This disclosure relates to an internal combustion engine control device.

[0002] International Publication No. 2023 / 209893 discloses an internal combustion engine control device for an engine.

[0003] Recently, better technologies have been desired for the control of internal combustion engines.

[0004] One aspect of this disclosure is an opening control unit that controls the opening degree of a throttle valve of an internal combustion engine provided in the vehicle based on the operation amount of an operation member provided in the vehicle, an opening degree detection unit that detects the opening degree at a predetermined timing before the intake stroke starts, and an injection amount determination unit that determines a fuel injection amount based on the opening degree detected by the opening degree detection unit. The opening control unit can execute an opening degree change restriction control that temporarily restricts a change in the opening degree based on a change in the operation amount within a period until the intake stroke is completed. It is an internal combustion engine control device.

[0005] FIG. 1 is a schematic diagram showing a part of a vehicle according to an embodiment. FIG. 2 is a block diagram showing the configuration of an arithmetic unit provided in the internal combustion engine control device of FIG. 1 in more detail. FIG. 3 is a graph illustrating a time-series change in throttle opening when the vehicle accelerates. FIG. 4 is a flowchart of an internal combustion engine control method according to an embodiment. FIG. 5 is a graph illustrating a time-series change in throttle opening according to Modification 1. FIG. 6 is a graph illustrating a time-series change in throttle opening according to Modification 2. FIG. 7 is a graph illustrating a time-series change in throttle opening according to Modification 3. FIG. 8 is a graph illustrating a time-series change in throttle opening according to Modification 4.

[0006] The amount of air introduced into the combustion chamber (intake volume) is determined based on the throttle valve opening detected at a predetermined timing before the intake stroke. Based on the determined intake volume and a predetermined air-fuel ratio, the amount of fuel injected to obtain a good air-fuel mixture is determined. However, if the throttle valve opening changes during the intake stroke due to acceleration or deceleration, there will be a discrepancy between the intake volume determined when the fuel injection amount was decided and the intake volume at the time of actual fuel injection. Due to these circumstances, achieving a good air-fuel ratio has not always been easy in the past.

[0007] Based on the preliminary explanation above, one embodiment will be described below. In the following description, the term "program" (computer program, computer software) is also referred to as a "computer program product." A computer program product is not limited to programs stored on a storage medium, but also includes programs transmitted, distributed, or downloaded via networks such as the Internet.

[0008] (One Embodiment) Figure 1 is a schematic diagram showing a part of a vehicle 10 according to one embodiment.

[0009] Vehicle 10 is, for example, a motorcycle such as a scooter, but is not limited to this. Vehicle 10 may also be a four-wheeled vehicle or the like. As shown in Figure 1, vehicle 10 comprises an internal combustion engine 12 and an internal combustion engine control device 14. In this embodiment, the case in which the internal combustion engine 12 is a single-cylinder engine is described, but the internal combustion engine 12 may be a multi-cylinder engine. Also, in this embodiment, the case in which the internal combustion engine 12 (single-cylinder engine) is a four-stroke engine is described (see also Figure 3), but the internal combustion engine 12 may be a two-stroke engine.

[0010] The internal combustion engine 12 comprises a cylinder 16, a piston 18, a connecting rod 20, a crankshaft 22, and a cylinder head 24.

[0011] The piston 18 is located inside the cylinder 16. The piston 18 is connected to the crankshaft 22 via a connecting rod 20. As the piston 18 reciprocates inside the cylinder 16, the crankshaft 22 rotates.

[0012] A cylinder head 24 is provided at one end of the cylinder 16 in the direction of movement of the piston 18. The cylinder head 24 defines the top dead center position of the piston 18. The space enclosed by the cylinder head 24, the piston 18, and the inner wall of the cylinder 16 is formed as the combustion chamber 26 of the internal combustion engine 12. The combustion chamber 26 is connected to an intake passage 28 and an exhaust passage 30. More specifically, the cylinder head 24 has an intake port 32 and an exhaust port 34. The intake port 32 is a port (opening) that connects the combustion chamber 26 and the intake passage 28. The exhaust port 34 is a port (opening) that connects the combustion chamber 26 and the exhaust passage 30.

[0013] The cylinder head 24 is also equipped with an intake valve 36 and an exhaust valve 38. The intake valve 36 is located in the intake port 32. The exhaust valve 38 is located in the exhaust port 34. The intake valve 36 and the exhaust valve 38 can be connected to the crankshaft 22 via a cam (not shown). In response to the rotation of the crankshaft 22, the intake valve 36 opens and closes the intake port 32. Similarly, in response to the rotation of the crankshaft 22, the exhaust valve 38 opens and closes the exhaust port 34.

[0014] The operation of opening the intake port 32 by the intake valve 36 will also be referred to as the opening operation in the following description. Similarly, the operation of closing the intake port 32 by the intake valve 36 will also be referred to as the closing operation in the following description.

[0015] The internal combustion engine 12 is further equipped with a throttle device 40, a fuel injection device 42, and an ignition device 44.

[0016] The throttle device 40 is a device having a throttle valve 40a and a valve drive unit 40b. For example, an electronically controlled throttle body is included in the throttle device 40. The throttle valve 40a is a valve whose opening degree can be adjusted. For example, a butterfly valve may be used as the throttle valve 40a. The throttle valve 40a is disposed in the intake passage 28. The valve drive unit 40b drives the throttle valve 40a to change the throttle opening degree (the opening degree of the throttle valve 40a). The valve drive unit 40b has an electric motor (not shown). The throttle valve 40a is driven by this electric motor. The intake volume may change in accordance with the change in the throttle opening degree.

[0017] The fuel injection device 42 has a fuel injection valve 42a capable of injecting fuel such as gasoline. The fuel injection valve 42a is disposed between the throttle valve 40a and the combustion chamber 26.

[0018] The fuel injected from the fuel injection valve 42a mixes with the air that has passed through the throttle valve 40a. When the intake valve 36 opens the intake port 32, the fuel-air mixture is introduced into the combustion chamber 26 through the intake port 32. The fuel injection valve 42a may also be located in the combustion chamber 26. In that case, the fuel and the air introduced into the combustion chamber 26 through the intake port 32 mix in the combustion chamber 26.

[0019] The ignition device 44 has a spark plug 44a. The spark plug 44a is located in the combustion chamber 26. The spark plug 44a ignites the fuel-air mixture by generating a spark. As a result, the fuel-air mixture burns. The energy generated by the combustion of the fuel-air mixture drives the piston 18. The exhaust gas generated by the combustion of the fuel-air mixture is discharged into the exhaust passage 30 through the exhaust port 34, which is opened by the exhaust valve 38.

[0020] Vehicle 10 is further equipped with various sensors. For example, a crank angle sensor 46, an opening degree sensor 48, and an operating amount sensor 50 are provided in vehicle 10.

[0021] The crank angle sensor 46 is a sensor that outputs a signal in response to changes in the crank angle. The crank angle is the rotation angle of the crankshaft 22. The crankshaft 22 may be equipped with a signal rotor 52 that rotates integrally with the crankshaft 22. In that case, the crank angle sensor 46 may be a sensor that outputs a signal in response to the rotation of the signal rotor 52.

[0022] The throttle position sensor 48 is a sensor that outputs a signal in response to changes in the throttle opening. The throttle position sensor 48 is, for example, a position sensor provided in the throttle device 40.

[0023] The operation amount sensor 50 is a sensor that outputs a signal in response to the operation of the vehicle 10 by the user (driver) on the operation member 54. The operation member 54 is a component provided in the vehicle 10 to receive operation to change the throttle opening. For example, the throttle grip, accelerator pedal, etc., are included in the operation member 54. The operation amount sensor 50 is, for example, an accelerator position sensor provided on these operation members 54.

[0024] The internal combustion engine control device 14 is a control device that controls at least the throttle device 40 of the internal combustion engine 12. For example, a computer such as an ECU (Electronic Control Unit) is included in the internal combustion engine control device 14. The internal combustion engine control device 14 comprises a storage unit 56 and a calculation unit 58.

[0025] The storage unit 56 includes one or more memory devices. The storage unit 56 includes non-volatile memory such as ROM (Read Only Memory), flash memory, or magnetic disk. Non-volatile memory is a storage medium that stores programs, tables, maps, etc., on a non-temporary basis. The storage unit 56 may also include volatile memory such as RAM (Random Access Memory).

[0026] The arithmetic unit 58 includes a processing circuit capable of performing arithmetic processing. This processing circuit may have one or more processors. For example, the processing circuit may have a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc. The processing circuit may also have ICs (Integrated Circuits), discrete devices, etc., other than processors.

[0027] Figure 2 is a block diagram showing in more detail the configuration of the calculation unit 58 provided in the internal combustion engine control device 14 of Figure 1.

[0028] The calculation unit 58 includes an opening degree control unit 60, an opening degree detection unit 62, an injection amount determination unit 64, an injection control unit 66, and an ignition control unit 68. The opening degree control unit 60, the opening degree detection unit 62, the injection amount determination unit 64, the injection control unit 66, and the ignition control unit 68 are realized by the processing circuit described above. For example, the opening degree control unit 60, the opening degree detection unit 62, the injection amount determination unit 64, the injection control unit 66, and the ignition control unit 68 are realized by one or more processors executing a program stored in the memory unit 56. ICs, discrete devices, etc., may realize at least a part of the opening degree control unit 60, the opening degree detection unit 62, the injection amount determination unit 64, the injection control unit 66, and the ignition control unit 68.

[0029] The throttle opening control unit 60 acquires the amount of operation of the operating member 54 based on the signal output from the operating amount sensor 50. The throttle opening control unit 60 also performs a change in the throttle opening based on the change in the amount of operation of the operating member 54.

[0030] The valve opening control unit 60 performs the opening change by controlling the valve drive unit 40b. The valve opening control unit 60 may also control a drive circuit 70 connected to the valve drive unit 40b (motor motor) (see also Figure 1). The drive circuit 70 is a circuit that supplies power to the motor based on a command signal output from the calculation unit 58 (processing circuit) by the valve opening control unit 60. By controlling the drive circuit 70, the valve opening control unit 60 can substantially control the valve drive unit 40b having a motor. The drive circuit 70 may be provided in the control device, but is not limited thereto. The drive circuit 70 may be provided in the valve drive unit 40b (throttle device 40), or it may be interposed between the control device and the throttle device 40.

[0031] The throttle opening detection unit 62 detects the throttle opening based on the signal output from the throttle opening sensor 48. At least the throttle opening detection unit 62 acquires the throttle opening at a predetermined detection timing tc based on the signal output from the throttle opening sensor 48 at that predetermined detection timing tc.

[0032] The predetermined detection timing tc is a predetermined timing before the intake stroke included in the combustion cycle of the internal combustion engine 12 begins (see also Figure 3). Therefore, the throttle opening detection unit 62 detects the throttle opening at least once for each repeatable combustion cycle. The throttle opening detection unit 62 determines whether or not it is the predetermined detection timing tc based on the signal output from the crank angle sensor 46.

[0033] The injection amount determination unit 64 determines the fuel injection amount based on the throttle opening detected by the opening detection unit 62 and a predetermined air-fuel ratio. More specifically, the injection amount determination unit 64 determines the fuel injection amount based on the intake air volume, which is determined based on the throttle opening at a predetermined detection timing tc, and a predetermined air-fuel ratio. The fuel injection amount is the amount of fuel injected from the fuel injection valve 42a. The injection amount determination unit 64 may determine the intake air volume using a table, function, etc., that shows the correspondence between the throttle opening and the intake air volume.

[0034] The injection control unit 66 controls the fuel injection device 42 based on the fuel injection amount determined by the injection amount determination unit 64, causing fuel to be injected from the fuel injection valve 42a. The injection control unit 66 injects fuel into the fuel injection device 42 at a predetermined injection timing td. That is, the injection timing td may be before the intake valve 36 starts opening, or after the intake valve 36 starts opening (see also Figure 3). For example, the injection control unit 66 may inject fuel during the exhaust stroke, or after the intake stroke has started. The injection control unit 66 determines whether or not it is the injection timing td based on the signal output from the crank angle sensor 46.

[0035] The ignition control unit 68 controls the ignition device 44 to generate a spark at the spark plug 44a. This allows the combustion stroke included in the combustion cycle of the internal combustion engine 12 to occur. The ignition control unit 68 generates a spark at the spark plug 44a at, for example, a predetermined ignition timing. This ignition timing is, for example, after the compression stroke included in the combustion cycle of the internal combustion engine 12. The ignition control unit 68 determines whether or not it is ignition timing based on the signal output from the crank angle sensor 46.

[0036] The opening degree control unit 60 described above will be explained further. The opening degree control unit 60 includes an opening degree change limiting unit 72 and an opening degree correction unit 74.

[0037] The opening degree change limiting unit 72 restricts changes in the opening degree. That is, the opening degree change limiting unit 72 restricts changes in the opening degree during the restriction period RP. The restriction period RP is a part of the combustion cycle (see also Figure 3). Therefore, the opening degree change limiting unit 72 temporarily restricts changes in the opening degree for each repeatable combustion cycle. The opening degree change limiting unit 72 determines whether or not it is the restriction period RP based on the signal output from the crank angle sensor 46.

[0038] The throttle opening change restriction control includes at least one of a first restriction control and a second restriction control. The first restriction control is a control that restricts the increase in throttle opening. The second restriction control is a control that restricts the decrease in throttle opening.

[0039] The throttle opening change limiting unit 72 may suppress the amount of change in the throttle opening per unit time during the limiting period RP. That is, the throttle opening change limiting unit 72 may make the opening and closing speed of the throttle opening during the limiting period RP slower than the opening and closing speed of the throttle opening during periods other than the limiting period RP. In this case, the first limiting control may include control to suppress the opening speed of the throttle valve 40a during the limiting period RP. The second limiting control may also include control to suppress the closing speed of the throttle valve 40a during the limiting period RP.

[0040] The throttle opening change limiting unit 72 may maintain the throttle opening constant during the limiting period RP. In this case, the throttle opening control unit 60 does not change the throttle opening in response to throttle operation.

[0041] The throttle opening correction unit 74 corrects the throttle opening after the restriction period RP based on the amount of operation during the restriction period RP. That is, the driver can operate the operating member 54 even during the restriction period RP, but the change in the throttle opening based on the change in the amount of operation during the restriction period RP is restricted by the throttle opening change restriction unit 72. After the restriction period RP, the throttle opening correction unit 74 changes the throttle opening based on the change in the amount of operation during the restriction period RP.

[0042] Figure 3 is a graph illustrating the time-series change in throttle opening (solid line) when vehicle 10 is accelerating. The dashed line EXC in Figure 3 shows the time-series change in throttle opening when vehicle 10 is accelerating without throttle opening change restriction control being performed (comparative example), for comparison with the solid line.

[0043] The start point ta and the end point tb of the above-mentioned deadline period RP are illustrated in FIG. 3. As shown in FIG. 3, the deadline period RP starts, for example, during the exhaust stroke. Also, the deadline period RP ends, for example, together with the intake stroke. That is, the deadline period RP ends, for example, when the intake port 32 is closed by the intake valve 36.

[0044] The above-mentioned predetermined detection timing tc and the injection timing td are further shown in FIG. 3. The illustration of the ignition timing is omitted.

[0045] The predetermined detection timing tc is preferably included in the exhaust stroke. In that case, as shown in FIG. 3, the predetermined detection timing tc may be included in the above-mentioned deadline period RP. The predetermined detection timing tc may coincide with the start point ta of the deadline period RP.

[0046] The fuel injection amount required for the intake stroke is determined based on the throttle opening at the predetermined detection timing tc. Therefore, inevitably, the injection timing td is after the predetermined detection timing tc. The injection timing td is preferably included in the deadline period RP.

[0047] As described above, the opening correction unit 74 corrects the throttle opening after the deadline period RP based on the operation amount during the deadline period RP. Thereby, as shown in FIG. 3, the throttle opening can change relatively steeply after the end point tb of the deadline period RP. The opening correction unit 74 completes the correction of the throttle opening based on the operation amount in one deadline period RP after the intake stroke and before the next deadline period RP of the one deadline period RP starts. Thereby, the throttle opening (solid line) at the time point te (after the intake stroke) when the correction is completed may be adjusted to a level comparable to the throttle opening (dashed line EXC) in the comparative example.

[0048] FIG. 4 is a flowchart of an internal combustion engine control method according to an embodiment.

[0049] The internal combustion engine control device 14 described above can execute the internal combustion engine control method shown in Figure 4. For example, a processing circuit (one or more processors) provided in the internal combustion engine control device 14, which is a computer, executes the internal combustion engine control method shown in Figure 4 based on a program stored in memory. As shown in Figure 4, the internal combustion engine control method includes an opening degree change restriction start step S1, an opening degree detection step S2, an injection amount determination step S3, an injection control step S4, and an opening degree change restriction end step S5. The internal combustion engine control device 14 can repeatedly execute the flowchart shown in Figure 4 in accordance with the repetition of the combustion cycle.

[0050] In the opening degree change restriction start step S1, the opening degree control unit 60 (opening degree change restriction unit 72) starts restricting the opening degree change. The timing of the execution of the opening degree change restriction start step S1 corresponds to the start point ta of the restriction period RP (see also Figure 3).

[0051] In the throttle opening detection step S2, the throttle opening detection unit 62 detects the throttle opening based on the signal output from the throttle opening sensor 48. The timing of the execution of the throttle opening detection step S2 corresponds to a predetermined detection timing tc (see also Figure 3).

[0052] As described above, the starting point ta of the restriction period RP and the predetermined detection timing tc may coincide. Therefore, the opening degree change restriction start step S1 and the opening degree detection step S2 may be started simultaneously.

[0053] In the injection amount determination step S3, the injection amount determination unit 64 determines the combustion injection amount. The injection amount determination unit 64 can determine the combustion injection amount based on the throttle opening detected in the throttle opening detection step S2 and a predetermined air-fuel ratio. The timing of the execution of the injection amount determination step S3 is after the throttle opening detection step S2.

[0054] In injection control step S4, the injection control unit 66 controls the fuel injector 42 to inject fuel. The injection control unit 66 controls the fuel injector 42 based on the fuel injection amount determined in injection amount determination step S3. The timing of execution of injection control step S4 corresponds to the injection timing td (see also Figure 3).

[0055] In the opening degree change restriction termination step S5, the opening degree control unit 60 (opening degree change restriction unit 72) terminates the restriction on opening degree changes. The timing of the execution of the opening degree change restriction termination step S5 corresponds to the end point tb of the restriction period RP (see also Figure 3).

[0056] According to this embodiment, the internal combustion engine control device 14 provides the following effects, for example.

[0057] The internal combustion engine control device 14 includes an opening degree control unit 60. The opening degree control unit 60 can temporarily restrict changes in the throttle opening degree based on changes in the amount of operation of the operating member 54 for the period until the intake stroke is completed. This can suppress the discrepancy between the intake air volume known when the fuel injection amount was determined and the intake air volume when fuel is actually injected. In other words, the discrepancy between the desired air-fuel ratio and the actual air-fuel ratio can be suppressed.

[0058] As shown in Figure 3, the throttle opening may be kept constant during the restriction period RP. In other words, in throttle opening change restriction control, the throttle opening may be kept constant within the aforementioned period until the intake stroke is completed. This can suppress both an excessively rich mixture and an excessively lean mixture.

[0059] As shown in Figure 3, the starting point ta of the restriction period RP may be during the exhaust stroke. That is, in throttle opening change restriction control, the restriction on changes in throttle opening may start during the exhaust stroke. In a typical combustion cycle such as a four-stroke engine cycle, the exhaust stroke is the stroke immediately preceding the intake stroke. By setting the starting point ta of the restriction period RP near the intake stroke, the length of the restriction period RP is suppressed. That is, by setting the starting point ta of the restriction period RP near the intake stroke, the length of the period during which changes in the amount of operation of the operating member 54 are not quickly reflected in the rotational speed of the internal combustion engine 12 is suppressed. This can lead to good drivability.

[0060] Vehicle 10 is, for example, a motorcycle. The internal combustion engine 12 is, for example, a single-cylinder engine. Smaller motorcycles such as scooters tend to be equipped with single-cylinder engines. When vehicle 10 is equipped with a single-cylinder engine, it is more susceptible to adverse effects on drivability due to poor combustion of the air-fuel mixture compared to when vehicle 10 is equipped with a multi-cylinder engine. A deterioration in the air-fuel ratio induces poor combustion of the air-fuel mixture. Considering these circumstances, this embodiment, which can achieve a good air-fuel ratio, is particularly useful when applied to motorcycles and the like equipped with a single-cylinder engine.

[0061] The throttle opening control unit 60 corrects the throttle opening after the limiting period RP based on the amount manipulated during the limiting period RP. This allows the throttle opening control unit 60 to achieve a good air-fuel ratio for the air-fuel mixture while also achieving the vehicle speed desired by the driver.

[0062] One embodiment may be modified as described below. In the following description, any explanations that overlap with the first embodiment will be omitted as appropriate. Reference numerals used for drawing reference in the first embodiment will be used in the following description unless otherwise specified.

[0063] (Modification 1) Figure 5 is a graph illustrating the time-series change of throttle opening according to Modification 1. Figure 5 shows the time-series change of throttle opening when the vehicle 10 is accelerating.

[0064] The predetermined detection timing tc (throttle opening detection step S2) may be earlier than the start point ta of the restriction period RP (throttle opening change restriction start step S1). In this case, it is preferable that the predetermined detection timing tc and the start point ta of the restriction period RP are included in the same stroke of the combustion cycle. For example, if the start point ta of the restriction period RP is during the exhaust stroke, it is preferable that the predetermined detection timing tc is also during the exhaust stroke. This makes it possible to suppress the discrepancy between the intake air volume determined based on the throttle opening detected at the predetermined detection timing tc and the intake air volume when fuel is actually injected, even if the predetermined detection timing tc is earlier than the start point ta of the restriction period RP.

[0065] (Modification 2) Figure 6 is a graph illustrating the time-series change of throttle opening according to Modification 2. Figure 6 shows the time-series change of throttle opening when the vehicle 10 is accelerating.

[0066] In relation to the first modification, if the predetermined detection timing tc is before the start point ta of the limiting period RP, then the injection timing td (injection control step S4) may also be before the start point ta of the limiting period RP.

[0067] (Modification 3) Figure 7 is a graph illustrating the time-series change of throttle opening according to Modification 3. Figure 7 shows the time-series change of throttle opening when the vehicle 10 is accelerating.

[0068] The starting point ta of the restriction period RP may be during the intake stroke. That is, after the intake valve 36 starts opening, the internal combustion engine control device 14 may execute the opening degree change restriction start step S1.

[0069] Furthermore, the endpoint tb of the restriction period RP may be before the end of the intake stroke. That is, the internal combustion engine control device 14 may execute the opening degree change restriction termination step S5 before the intake valve 36 completes its closing operation.

[0070] (Modification 4) Figure 8 is a graph illustrating the time-series change of throttle opening according to Modification 4. Figure 8 shows the time-series change of throttle opening when the vehicle 10 is accelerating.

[0071] In relation to Modification 3, the endpoint tb of the restriction period RP may be before the start of the intake stroke. For example, the endpoint tb of the restriction period RP may be during the exhaust stroke. In this case, the opening degree can be changed based on the change in the manipulated amount during the intake stroke, but the opening degree change may be temporarily restricted before the start of the intake stroke. Therefore, even in this modification, the discrepancy between the perceived intake air volume and the intake air volume when fuel is actually injected can be suppressed compared to the comparative example (dashed line EXC) in which the opening degree change restriction control is not performed.

[0072] (Modification 5) If the amount of the operating member 54 reaches a first operating amount threshold due to an operation to increase the throttle opening, the opening control unit 60 may release the opening change restriction control. That is, if the amount of the operating member reaches a first operating amount threshold due to an operation to accelerate the vehicle 10, the opening control unit 60 may release the opening change restriction control. The first operating amount threshold is a predetermined threshold.

[0073] According to this modified example, if the amount of operation reaches a first threshold due to an operation to accelerate the vehicle 10, the throttle opening control unit 60 changes the throttle opening based on the change in the amount of operation, even if it is within the aforementioned limit period RP. As a result, the driver's intention to accelerate the vehicle 10 significantly is prioritized, and a good sense of operation and acceleration can be provided to the driver.

[0074] If the manipulated amount falls below the first manipulated amount threshold, the opening degree control unit 60 may restart the opening degree change restriction control.

[0075] (Modification 6) If the amount of the operating amount of the operating member 54 increases per unit time due to an operation to increase the throttle opening, the opening control unit 60 may release the opening change restriction control. That is, if the amount of the operating amount increases per unit time due to an operation to accelerate the vehicle 10, the opening control unit 60 may release the opening change restriction control. The second operating amount threshold is a predetermined threshold.

[0076] According to this modified example, if the increase in the amount of the manipulated variable per unit time due to an operation to accelerate the vehicle 10 reaches the second threshold for the manipulated variable, the throttle opening control unit 60 changes the throttle opening based on the change in the manipulated variable, even if it is within the aforementioned limit period RP. As a result, the driver's intention to accelerate the vehicle 10 quickly is given priority, and a good sense of operation and acceleration can be provided to the driver.

[0077] If the increase in the manipulated amount per unit time falls below the second manipulated amount threshold, the opening degree control unit 60 may restart the opening degree change restriction control.

[0078] (Modification 7) Although not shown in the diagram, if the internal combustion engine 12 is a multi-cylinder engine, the internal combustion engine 12 has a plurality of cylinders 16. In addition, a plurality of throttle valves 40a corresponding to each of the plurality of cylinders 16 may be provided in the vehicle 10. Based on this, if the internal combustion engine 12 is a multi-cylinder engine, the opening degree control unit 60 may control the opening degree of each of the plurality of throttle valves 40a by opening degree change limit control.

[0079] For example, if the internal combustion engine 12 is a multi-cylinder engine, each of the multiple cylinders 16 performs a combustion cycle, but the operation of the multiple cylinders 16 may not be synchronized. Taking this into account, a first restriction period and a second restriction period may be set in advance. The first restriction period is the restriction period RP corresponding to the first cylinder, which is one of the multiple cylinders 16. The second restriction period is the restriction period RP corresponding to the second cylinder, which is another of the multiple cylinders 16. The opening degree control unit 60 restricts the change in the opening degree of the first throttle valve, which is the throttle valve 40a corresponding to the first cylinder, during the first restriction period. The opening degree control unit 60 also restricts the change in the opening degree of the second throttle valve, which is the throttle valve 40a corresponding to the second cylinder, during the second restriction period.

[0080] According to this modified example, a good air-fuel mixture can be supplied to each of the multiple cylinders 16 provided in the multi-cylinder engine.

[0081] (Combinations of multiple variations) The above-mentioned variations may be combined as appropriate, as long as they do not contradict each other.

[0082] The following additional information is disclosed regarding the embodiments and modifications described above.

[0083] (Note 1) The internal combustion engine control device (14) according to the present disclosure includes: an opening degree control unit (60) that controls the opening degree of a throttle valve (40a) of an internal combustion engine (12) provided in a vehicle (10) based on the amount of operation of an operating member (54) provided in the vehicle; an opening degree detection unit (62) that detects the opening degree at a predetermined timing before the intake stroke starts; and an injection amount determination unit (64) that determines the fuel injection amount based on the opening degree detected by the opening degree detection unit, wherein the opening degree control unit can perform opening degree change restriction control that temporarily restricts the change in the opening degree based on the change in the operating amount within the period until the intake stroke is completed. This makes it possible to achieve a good air-fuel ratio.

[0084] (Note 2) The internal combustion engine control device described in Note 1 may also be an internal combustion engine control device in which, in the opening degree change limit control, the opening degree is maintained constant within the period until the intake stroke is completed. This can suppress both the air-fuel mixture becoming excessively rich and the air-fuel mixture becoming excessively lean.

[0085] (Note 3) The internal combustion engine control device described in Note 1 or 2 may be an internal combustion engine control device in which the change in the manipulated amount is caused by an operation to increase the opening degree.

[0086] (Note 4) The internal combustion engine control device described in Note 3 may also be an internal combustion engine control device in which, when the amount of operation reaches a predetermined first threshold amount due to an operation to increase the opening degree, the opening degree control unit releases the opening degree change restriction control. This may provide the driver with a good feel for operation, acceleration, etc.

[0087] (Note 5) The internal combustion engine control device described in Note 3 may also be an internal combustion engine control device in which, when the amount of increase per unit time of the manipulated amount due to an operation to increase the opening degree reaches a predetermined second threshold of the manipulated amount, the opening degree control unit releases the opening degree change restriction control. This may provide the driver with a good feel for operation, acceleration, etc.

[0088] (Note 6) The internal combustion engine control device described in Note 1 or 2 may be an internal combustion engine control device in which the change in the manipulated amount is caused by an operation to reduce the opening degree.

[0089] (Note 7) An internal combustion engine control device described in any one of Notes 1 to 6 may be an internal combustion engine control device in which, in the opening degree change limit control, the limit on the change in the opening degree based on the change in the manipulated amount is started during the exhaust stroke. This can achieve good drivability.

[0090] (Note 8) An internal combustion engine control device described in any one of Notes 1 to 7, wherein fuel injection based on the fuel injection amount is started during the exhaust stroke.

[0091] (Note 9) An internal combustion engine control device as described in any one of Notes 1 to 8, wherein in the opening degree change limiting control, the amount of change in the opening degree per unit time is suppressed within the period until the intake stroke is completed.

[0092] (Note 10) An internal combustion engine control device described in any one of Notes 1 to 9, wherein the internal combustion engine is a single-cylinder engine.

[0093] (Note 11) The internal combustion engine control device described in any one of Notes 1 to 9 may be an internal combustion engine control device in which the internal combustion engine is a multi-cylinder engine having a plurality of cylinders (16), a plurality of throttle valves corresponding to each of the plurality of cylinders are provided in the vehicle, and the opening degree control unit can control the opening degree of each of the plurality of throttle valves by the opening degree change limit control. This ensures that a good air-fuel mixture is supplied to each of the plurality of cylinders.

[0094] (Note 12) An internal combustion engine control device described in any one of Notes 1 to 11, wherein the vehicle is a motorcycle.

[0095] While this disclosure has been described in detail, it is not limited to the individual embodiments described above. These embodiments can be added, replaced, modified, partially deleted, etc., in any way that does not depart from the gist of this disclosure or from the intent of this disclosure derived from the claims and their equivalents. These embodiments can also be implemented in combination. For example, the order of operations and processes in the embodiments described above are given as examples only and are not limited thereto. The same applies when numerical values ​​or mathematical formulas are used in the description of the embodiments described above.

[0096] 10...Vehicle 12...Internal combustion engine 14...Internal combustion engine control device 16...Cylinder 40a...Throttle valve 54...Operating member 60...Opening degree control unit 62...Opening degree detection unit 64...Injection amount determination unit

Claims

1. An internal combustion engine control device (14) comprising: an opening degree control unit (60) that controls the opening degree of a throttle valve (40a) of an internal combustion engine (12) provided in a vehicle (10) based on the amount of operation of an operating member (54) provided in the vehicle; an opening degree detection unit (62) that detects the opening degree at a predetermined timing before the intake stroke starts; and an injection amount determination unit (64) that determines the fuel injection amount based on the opening degree detected by the opening degree detection unit, wherein the opening degree control unit can perform opening degree change restriction control that temporarily restricts the change in the opening degree based on the change in the operating amount for a period until the intake stroke is completed.

2. An internal combustion engine control device according to claim 1, wherein, in the opening degree change limit control, the opening degree is maintained constant within the period until the intake stroke is completed.

3. An internal combustion engine control device according to claim 1 or 2, wherein the change in the manipulated amount is caused by an operation to increase the opening degree.

4. An internal combustion engine control device according to claim 3, wherein when the amount of operation reaches a predetermined first threshold of operation due to an operation to increase the opening degree, the opening degree control unit releases the opening degree change restriction control.

5. An internal combustion engine control device according to claim 3, wherein when the amount of increase per unit time of the manipulated amount reaches a predetermined second manipulated amount threshold due to an operation to increase the opening degree, the opening degree control unit releases the opening degree change restriction control.

6. An internal combustion engine control device according to claim 1 or 2, wherein the change in the manipulated amount is caused by an operation to reduce the opening degree.

7. An internal combustion engine control device according to claim 1 or 2, wherein in the opening degree change limit control, the limit on the change of the opening degree based on the change in the manipulated amount is started during the exhaust stroke.

8. An internal combustion engine control device according to claim 1 or 2, wherein fuel injection based on the fuel injection amount is started during the exhaust stroke.

9. An internal combustion engine control device according to claim 1 or 2, wherein in the opening degree change limiting control, the amount of change in the opening degree per unit time is suppressed within the period until the intake stroke is completed.

10. An internal combustion engine control device according to claim 1 or 2, wherein the internal combustion engine is a single-cylinder engine.

11. An internal combustion engine control device according to claim 1 or 2, wherein the internal combustion engine is a multi-cylinder engine having a plurality of cylinders (16), a plurality of throttle valves corresponding to each of the plurality of cylinders are provided in the vehicle, and the opening degree control unit can control the opening degree of each of the plurality of throttle valves by the opening degree change limit control.

12. An internal combustion engine control device according to claim 1 or 2, wherein the vehicle is a motorcycle.

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