Engine electronic control device

Abstract

To provide an engine electronic control device which estimates a high speed rotation of an engine by a method other than a normal control and switches to an emergency engine control once the high speed rotation is estimated.SOLUTION: An engine electronic control device detects the acceleration of an operator by a throttle valve sensor, detects the switching of a gear by the operator by a gear position sensor, and estimates a high speed rotation in which a rotation speed of the engine is a predefined rotation speed or more. Since a normal engine control is not used in an estimation of the high speed rotation of the engine, the high speed rotation can be estimated with no detection delay even in, for example, an engine of a high speed of 10000 rotations or more per minute. During the estimation of the high speed rotation, the control of the engine electronic control device is switched from a normal engine control to an emergency engine control. The emergency engine control has less number of control items than the normal engine control. Therefore, for example, even an engine of a high speed rotation of 10000 rotations or more per minute, the engine electronic control device can control the high speed rotation.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The description in this specification relates to an engine electronic control device, which is useful for electronically controlling an engine for driving a motorcycle, for example. [Background technology]

[0002] Patent Document 1 discloses that an electronic engine control device used in an engine for driving a vehicle predicts and reduces the impact on vehicle control caused by reducing the processing load during high load. As control for reducing the processing load, Patent Document 1 lists the operation process of the magnetic clutch of an air conditioner and the update process of battery voltage information as normal control processes to be thinned out. Patent Document 1 also lists the catalyst warm-up process at start-up and the process of calculating a correction amount for the engine operating state detected by various sensors at start-up as low-priority stop processes. In addition, as processes to be subject to medium-priority stop processes, Patent Document 1 lists an air conditioner cut-off process that stops the execution of the air conditioner or reduces the operating capacity of the air conditioner when starting. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-218467 A Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 does not state the engine speed, but it presupposes that electronic engine control is possible even when the engine speed is high, and stops other controlled objects such as the air conditioner when the load is high. In other words, Patent Document 1 presupposes that electronic engine control is possible even in the high load range, and does not perform control that is less necessary in the high load range. In other words, the engine electronic control device of Patent Document 1 continues normal engine control, but stops controls other than engine control by interrupting the engine control.

[0005] However, some engines rotate at high speeds, for example, at 10,000 revolutions per minute or more. In such high-speed engines, it may be difficult for the engine electronic control device to determine whether to perform controls other than engine control or to stop controls that are less necessary while controlling the high-speed engine rotation. In other words, there is a risk that the determination of controls other than high-speed engine rotation control will be delayed, or that the execution of controls other than rotation control will have a negative effect on the high-speed engine rotation control.

[0006] The present disclosure has been made in consideration of the above points, and aims to enable an engine electronic control device to accurately estimate high-speed engine revolutions in advance. In particular, the aim is to enable the engine electronic control device to estimate high-speed engine revolutions by a method other than the electronic control of the engine that the engine electronic control device normally performs. Furthermore, the aim is to switch the control of the engine electronic control device from normal engine control to emergency engine control when it is estimated that the engine revolution speed will be a high-speed revolution speed equal to or higher than a predetermined revolution speed. [Means for solving the problem]

[0007] The first aspect of the present disclosure is an engine electronic control device that electronically controls the operation of the engine, comprising an engine that performs an intake stroke of air and fuel, a compression stroke, an ignition and explosion stroke, and an exhaust stroke, a throttle valve that varies the amount of intake air to the engine in response to an operator's operation of the accelerator, an accelerator sensor that detects the opening degree of the accelerator by the operator, a drive transmission gear that transmits the engine speed to a drive shaft and varies the transmitted speed in response to the operator's gear shifting, and a gear position sensor that detects the gear shifting of the drive transmission gear by the operator.

[0008] A first engine electronic control device of the present disclosure detects acceleration by an operator using an accelerator sensor and detects gear switching by the operator using a gear position sensor, and estimates that the engine speed will be a high speed speed equal to or higher than a predetermined speed. When the high speed speed is estimated, the control of the engine electronic control device is switched from normal engine control to emergency engine control. The emergency engine control of the engine electronic control device has fewer control items than the normal engine control.

[0009] In the first engine electronic control device of the present disclosure, the high speed rotation of the engine is estimated by the accelerator sensor and the gear position sensor, so that normal engine control is not used for estimating the high speed rotation of the engine. Therefore, even if the engine rotates at a high speed of, for example, 10,000 revolutions per minute or more, the high speed rotation can be estimated without a detection delay. Furthermore, in the first engine electronic control device of the present disclosure, the normal engine control is switched to the emergency engine control when estimating the high speed rotation, so that even if the engine rotates at a high speed of, for example, 10,000 revolutions per minute or more, the high speed rotation can be controlled by the engine electronic control device.

[0010] The second electronic engine control device of the present disclosure switches from normal engine control to emergency engine control in accordance with a gear ratio coefficient based on the gear ratio of the gear detected by a gear position sensor and a throttle opening coefficient based on the throttle opening detected by an accelerator sensor, where the gear ratio coefficient is larger as the reduction ratio from the engine to the drive shaft is larger, and the throttle opening coefficient is larger as the opening of the throttle valve is larger.

[0011] In the second engine electronic control device of the present disclosure, it is estimated that the engine will reach a high speed of a predetermined rotation speed or more by using a gear ratio coefficient and a throttle opening coefficient. This makes it possible to estimate the high speed rotation of the engine without using control by a normal engine electronic control device.

[0012] The third electronic engine control device of the present disclosure switches from normal engine control to emergency engine control of the electronic engine control device when the product of the gear ratio coefficient and the throttle opening coefficient is equal to or greater than a predetermined threshold value. By appropriately weighting the gear ratio coefficient and the throttle opening coefficient, it becomes possible to accurately estimate high speed engine revolutions.

[0013] The fourth engine electronic control device of the present disclosure performs engine base control including engine speed, fuel supply to the engine, and ignition timing to the engine, and engine interrupt control according to engine speed in one cycle of normal engine control. In the fourth engine electronic control device of the present disclosure, when the engine is rotating at a high speed of more than a predetermined speed, the time for one engine revolution is shorter than the time for one cycle of normal engine control by the engine electronic control device. For example, in the case of an engine that rotates 15,000 times per minute, if the on-off signal from the crank angle sensor is repeated 20 times per engine revolution, the on-off signal will be 5,000 times per second. Therefore, the interrupt control time per signal is shortened, and if other processing such as interrupt prohibition processing occurs, the processing may not be executed. The fourth engine electronic control device of the present disclosure is designed to be controllable even in such a situation.

[0014] A fifth engine electronic control device of the present disclosure performs emergency preparation engine control from an estimation start timing at which it is estimated that the engine speed will reach a high speed equal to or higher than a predetermined speed to a timing before the engine reaches a high speed equal to or higher than the predetermined speed, and performs emergency engine control at a high speed rotation timing after the engine reaches a high speed equal to or higher than the predetermined speed. In the fifth engine electronic control device of the present disclosure, the emergency engine control has fewer control items than the emergency preparation engine control.

[0015] In the fifth engine electronic control device of the present disclosure, the high speed rotation of the engine is estimated by the throttle valve sensor and the gear position sensor, so that it is possible to estimate that the engine will rotate at a high speed of a predetermined speed or more in about 50 milliseconds. In contrast, a time lag of, for example, about 2 seconds occurs before the engine actually rotates at a high speed of a predetermined speed or more. In the fifth engine electronic control device of the present disclosure, this time lag can be utilized to perform emergency preparation engine control. Moreover, in the fifth engine electronic control device of the present disclosure, the emergency preparation engine control has more control items than the emergency engine control, so that a preparation stage for transitioning to the emergency engine control can be provided to soft-land the emergency engine control.

[0016] The sixth emergency preparation engine control of the present disclosure divides the emergency preparation engine control into a low-load emergency preparation engine control in which the engine is operating at a low load and a medium-load emergency preparation engine control in which the engine is operating at a medium load. The low-load emergency preparation engine control has more control items than the medium-load emergency preparation engine control.

[0017] In the sixth emergency preparation engine control of the present disclosure, the emergency preparation engine control is further divided into two stages to allow more detailed preparation. In particular, the number of control items in the low-load emergency preparation engine control is greater than that in the medium-load emergency preparation engine control, so that it is possible to gradually reduce the number of control items toward the emergency engine control. This allows a smoother soft landing for the emergency engine control.

[0018] The seventh engine electronic control device of the present disclosure performs only a part of the engine base control and the engine interrupt control in the emergency engine control. When the engine speed is at or above a certain level, the time per rotation is short and the controllable items are originally limited, so that only a part of the engine base control and the engine interrupt control is performed.

[0019] In the eighth engine electronic control device of the present disclosure, the number of reduction items in the engine interrupt control is greater than the number of reduction items in the engine base control in the emergency engine control. When the engine speed is particularly high, only the minimum necessary engine control is performed. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a side view of a motorcycle equipped with an engine electronic control device. [Diagram 2] FIG. 2 is a front view of the motorcycle shown in FIG. [Diagram 3] FIG. 3 is a diagram showing the configuration of the engine electronic control device. [Figure 4] FIG. 4 is a table showing control items in engine-based control. [Diagram 5] FIG. 5 is a table showing control items in engine interruption control. [Figure 6] FIG. 6 is a graph illustrating engine control processing under low load without using emergency engine control. [Figure 7] FIG. 7 is a graph illustrating high load engine control without emergency engine control. [Figure 8] FIG. 8 is a diagram showing the gear ratio coefficient and the throttle opening coefficient. [Figure 9] FIG. 9 is a table showing factors for estimating high speed engine revolutions. [Figure 10] FIG. 10 is a diagram showing the processing load state in the emergency preparation engine control. [Figure 11] FIG. 11 is a flowchart showing engine control when the processing load risk increases. [Figure 12] FIG. 12 is a flowchart showing engine control when the processing load risk is reduced. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] An example of the present disclosure will be described below with reference to the drawings. Figures 1 and 2 show a motorcycle 300 which is an example equipped with an engine 200 whose rotation is controlled by an engine electronic control device 100 according to the present disclosure. The engine 200 of the motorcycle 300 is covered by a cowl 301, and the front wheel 1 shows the position of engine 200. Front wheel 302 is connected to handlebars 305 via front forks 304. In addition, since ECU 215, which will be described later, of engine electronic control device 100 is disposed below seat 313, FIG. 1 shows the position of engine electronic control device 100 (ECU 215). Note that a front suspension 306 that absorbs vibrations of front wheel 302 is disposed between front forks 304 and front wheel 302.

[0022] The right grip of the handlebar 305 also serves as an accelerator 307, and by turning the accelerator 307, the amount of intake air supplied to the engine 200 is variably controlled. A brake lever 308 is also provided on the right grip. Although not shown, a brake pedal that is operated with the foot is provided below the engine 200 on the right side of the motorcycle 300. On the other hand, the left grip 309, has a clutch lever 310 provided.

[0023] The output of the engine 200 is transmitted to the rear wheel 303 via a chain 311. Therefore, in this example, the shaft of the rear wheel 303 serves as the drive shaft. A gasoline tank 312 is disposed above the engine 200. A seat 313 is disposed behind the gasoline tank 312, and a seat cowl 314 is disposed below the seat 313. The output of the engine 200 is transmitted to the chain 311 via a drive transmission gear 315 disposed adjacent to the engine 200. Note that FIG. 1 shows the location of the drive transmission gear 315, and the drive transmission gear 315 itself is covered by a cowl 301. The drive transmission gear 315 transmits the rotation of the engine 200 to the rear wheel 303, and changes the number of rotations transmitted in response to gear switching by the rider, who is the operator. The rider operates the clutch lever 310 with his left hand and operates a pedal (not shown) with his foot to switch the gear of the drive transmission gear 315. A gear position sensor 316 (shown in FIG. 3) incorporated in the drive transmission gear 315 detects which gear the rider has selected.

[0024] 3 shows the configuration of an engine electronic control device 100 that controls the rotation of an engine 200. First, the engine 200 will be described. In the engine 200, a cylindrical cylinder 202 is formed in an aluminum cylinder block 201, and a piston 203 reciprocates within the cylinder 202. The reciprocating movement of the piston 203 is transmitted to a crankshaft 205 via a connecting rod 204, and the crankshaft 205 rotates within the cylinder block 201 while being supported by a bearing (not shown).

[0025] The rotating disk 206 rotates together with the crankshaft 205, and the rotation of the rotating disk 206 is detected by the crank angle sensor 207. Specifically, the crank angle sensor 207 is made of a magnetic pickup sensor. As the rotating disk 206 rotates, the position detection protrusion 208 also rotates, and when the position detection protrusion 208 faces the tip of a magnet built in the magnetic pickup sensor, the magnetic flux from the magnet is directed toward the position detection protrusion 208. The change in magnetic flux at this time changes the electric potential generated in the detection coil built in the magnetic pickup sensor. The magnetic pickup sensor detects the rotation angle of the rotating disk 206 based on the change in the electric potential of the detection coil. A hall sensor may be used for the crank angle sensor 207. In the case of a hall sensor, a magnet is arranged at the position of the position detection protrusion 208 on the rotating disk 206, and the rotation of the crankshaft 205 is detected by detecting the change in the magnetic flux of the magnet rotating together with the rotating disk 206.

[0026] A cooling water passage 209 is formed in the cylinder block 201, and the engine cooling water passing through the cooling water passage 209 prevents the temperature of the engine 200 from rising excessively. The engine cooling water passing through the cooling water passage 209 has its heat dissipated by a radiator (not shown). The radiator is disposed in front of the engine 200 in a position where it receives the wind generated by the running of the motorcycle 300.

[0027] An air filter 211 is disposed in an intake passage 210 of the engine 200, and the air filter 211 removes dust and the like from the intake air. A throttle valve 212 is also disposed in the intake passage 210. The throttle valve 212 is rotationally controlled by a motor 213, and varies the amount of intake air passing through the intake passage 210. Specifically, the opening degree of an accelerator 307 is detected by an accelerator sensor 214, and the rotation angle of the motor 213 is controlled in response to a signal from the accelerator sensor 214. More specifically, a signal from the accelerator sensor 214 is input to an ECU (engine control unit) 215, and the motor 213 rotates the throttle valve 212 in response to a signal from the ECU 215. The position of the throttle valve 212 is detected by a throttle valve sensor disposed at the motor 213, and is fed back to the ECU 215. The accelerator sensor 214 is also called an accelerator position sensor, and Fig. 3 shows the position where the accelerator sensor 214 is disposed. The pressure difference before and after the throttle valve 212 in the intake passage 210 is measured by a differential pressure gauge 216. Therefore, whether the throttle valve 212 is opening as planned is also fed back by this differential pressure gauge 216. Also, an intake pressure sensor 217 is disposed downstream of the throttle valve 212 in the intake passage 210.

[0028] An aluminum cylinder head 218 is disposed above a cylinder block 201 of the engine 200. An intake valve 219 that opens and closes an intake passage 210, and an exhaust valve 220 that opens and closes an exhaust passage 221 are disposed in the cylinder head 218. An ignition plug 222 is also disposed in the cylinder head 218. The ignition plug 222 receives a high voltage supplied from an ignition coil 223 and generates a spark discharge, igniting the mixture of gasoline fuel and intake air.

[0029] Gasoline fuel is injected into the intake passage 210 from an injector 224 disposed in the intake passage 210 near the intake valve 219. The amount and timing of gasoline fuel injection by the injector 224 are controlled by the ECU 215. In addition, gasoline fuel is supplied to the injector 224 by a fuel pump 225 disposed in the gasoline tank 312.

[0030] An oxygen concentration sensor 226 that detects the oxygen concentration in the exhaust is disposed in the exhaust passage 221. In order to keep the oxygen concentration at an optimum value at all times, the ECU 215 controls the amount of intake air and the amount of gasoline fuel, and also controls the timing of gasoline fuel injection and the timing of ignition of the spark plug 222. A catalyst 227 is also disposed in the exhaust passage 221. The catalyst 227 purifies the exhaust by oxidizing unburned materials such as carbon monoxide contained in the exhaust and reducing nitrogen oxides and the like.

[0031] In this way, the engine electronic control device 100 controls the rotation of the engine 200 based on signals from various sensors, mainly using the ECU 215. Next, the control items of the engine electronic control device 100 will be described. FIG. 4 shows the control items of the engine base control, which is the so-called basic control of the engine electronic control device 100. The input-related (SIG) control items include control of the engine speed calculation. The speed of the engine 200 is calculated by the ECU 215 upon receiving an output from the crank angle sensor 207. There is also control of engine stall determination. This stall determination is also based on a signal from the crank angle sensor 207, and the ECU 215 determines when the speed of the engine 200 falls below a certain speed. The determination of the starting state is performed by calculating the starting state of the engine 200, and the ECU 215 determines the position of the piston 203 of the engine 200 based on the signal from the crank angle sensor 207.

[0032] The control (CTR) includes overrun control C1 and speed limit control C2. Overrun control C1 prevents engine 200 from rotating beyond the rev limit, which is the allowable speed, and in this embodiment, controls it so that it does not greatly exceed 15,000 revolutions per minute. Speed ​​limit control C2 is a control that prevents the speed limit from being exceeded by a predetermined speed or more, and closes throttle valve 212 to reduce the amount of intake air or reduce the amount of gasoline fuel injected from injector 224.

[0033] The ignition system control (ESA) includes a current supply time control E1. The current supply time to the ignition coil 223 is controlled to control the discharge amount of the spark plug 222. An ignition inhibition control E2 controls the ignition itself of the spark plug 222. And an ignition cut and thinning control E3 controls whether or not the ignition plug 222 is ignited.

[0034] Injection system control (EFI) controls the injection of gasoline fuel from the injector 224. In fuel cut and thinning control F1, it controls whether or not gasoline fuel is injected from the injector 224. Injection control F2 is a basic control that controls the amount of gasoline fuel injected from the injector 224 and the injection timing. The above-mentioned fuel cut and thinning control was performed for each cylinder. For example, in a four-cylinder engine, fuel is not cut in all cylinders, but only in a specific cylinder (for example, the first cylinder). In contrast, all-cylinder fuel cut control F3 cuts fuel in all cylinders. In the case of a four-cylinder engine, fuel is cut in all four cylinders.

[0035] The above has been the engine base control of the engine 200. Next, engine interrupt control will be described with reference to FIG. 5. The engine interrupt control is an interrupt control that is called for each specific angle of the crankshaft 205 detected by the crank angle sensor 207. First, input-related (SIG) control items will be described. The input signal acquisition control S4 reads values ​​of various sensors that indicate the state of the motorcycle 300, and acquires a signal from the intake pressure sensor 217 by, for example, AD conversion. The intake pipe pressure control S5 converts the signal read by the sensor for control use. For example, the pressure in the intake passage 210 to the engine 200 is calculated based on the signal from the intake pressure sensor 217. The stroke discrimination control S6 manages the process of the engine 200 based on the calculated signal. The processes of the engine 200 are the intake stroke, compression stroke, ignition / explosion stroke, and exhaust stroke. For example, based on the signal from the intake pressure sensor 217, it is determined which stroke the engine 200 is in by pressure information (pulsation) in the intake passage 210. In atmospheric pressure control S7, for example, the atmospheric pressure is estimated based on a signal from the intake pressure sensor 217. Then, in misfire determination S8, which calculates the intake pipe pressure for misfire detection, the medium pressure in the intake passage 210 used for misfire determination is calculated from the pressure difference between the atmospheric pressure and the intake negative pressure based on the signal from the intake pressure sensor 217.

[0036] Next, the control (CTR) will be described. In the engine interrupt control, the control (CTR) performs launch control C3. The launch control C3 is a control to prevent the tires (rear wheels 303) from spinning, and suppresses a sudden increase in the number of revolutions above a predetermined value.

[0037] In the injection system control (EFI), the injection prohibition control F4 controls whether to permit or prohibit the injection of gasoline fuel from the injector 224. For example, gasoline fuel is not injected when the motorcycle 300 falls over. The injection calculation timing calculation F5 corrects the injection control F2 performed in the engine-based control. The fuel injection distribution coefficient calculation F6 adjusts the amount of gasoline fuel injected in each cylinder. The fuel injection control F7 finally determines the amount of gasoline fuel injected based on the values ​​calculated in the injection calculation timing calculation F5 and the fuel injection distribution coefficient calculation F6.

[0038] In the engine interrupt control in the ignition system control (ESA), the ignition mode management E5 is performed. The ignition mode is a switching between a fixed mode and a calculation mode. For example, during the momentary period immediately after the start of the engine 200 until the rotation speed increases, the ignition position of the spark plug 222 is fixed with respect to the position of the piston 203. In the calculation mode, the engine 200 is rotating, and the ignition position of the spark plug 222 is also calculated by the ECU 215 in the idling state or when the motorcycle 300 starts to run. Note that the ignition position refers to the position (rotation angle) at which the spark plug 222 is ignited in terms of the rotation position of the crankshaft 205, but from the perspective of the spark plug 222, it indicates the timing at which ignition is performed. Therefore, the ignition mode management E5 calculates the timing in the above-mentioned calculation mode. The ignition coil current lock prevention control E7 releases the state in which current supply to the spark plug 222 is locked by fail-safe processing. The spin limiter control E8 detects a situation where a spin is imminent based on the difference between the front wheel speed and the rear wheel speed, and if there is a difference, it determines that a spin is occurring. If it determines that a spin is occurring, it retards ignition or thins out ignition to reduce torque, thereby lowering the output of the engine 200. This improves the situation. Since the safety of the rider is given top priority, this is done by interrupt control.

[0039] In the engine interruption control, other controls (OTH) are also performed. The other controls (OTH) include air purge control O1. The air purge control O1 is a control for sucking evaporated fuel from the gasoline tank 312 into the intake passage 210, so that gasoline fuel can be mixed into the cylinder 202. The battery voltage drop warning control O2 detects that the engine 200 is not rotating when there is no input from the crank angle sensor 207 for a certain period of time after the power is turned on, and notifies the rider of a low battery. The fuel pump control O3 detects whether the fuel pump 225 has been driven for a certain period of time after inputting a signal from the crank angle sensor 207, and manages the drive of the fuel pump 225. The kickback prevention control O4 detects whether the engine 200 is rotating in reverse based on a signal from the crank angle sensor 207, and stops the supply of gasoline fuel and the ignition of the spark plug 222 when the engine 200 is rotating in reverse. The fan relay control O5 manages the drive of an engine fan (not shown). The steering damper control O6 is a control for reducing instability such as shaking of the steering wheel 305.

[0040] The engine interruption control also includes a misfire control (MF), which includes a misfire determination control M1 and a forced misfire control M2. The misfire determination control M1 creates data for misfire determination. And the forced misfire control M2 creates a pseudo misfire when you want to reproduce a misfire.

[0041] The engine interrupt control also includes a fault diagnosis (DIAG). In the ignition coil abnormality determination D1, it is determined whether the spark plug 222 is igniting as requested, and a fault in the ignition coil 223 is detected. In the injector abnormality determination D2, it is determined whether the injector 224 is injecting as requested, and a fault in the injector 224 is detected. In the crank sensor abnormality determination D3, a fault in the crank angle sensor 207 is detected when there is no output from the crank angle sensor 207 even though a starter (not shown) is rotating. And in the intake pipe pressure sensor abnormality determination D4, a fault in the intake pressure sensor 217 is detected.

[0042] The engine interrupt control also includes electronic throttle system control (ETV) and emulation control (ETK). The electronic throttle system control (ETV) uses an electric throttle operation mode determination control T1 to manage the drive of the motor 213 that rotates the throttle valve 212. And the emulation control (ETK) uses an emulation function K1 to connect the ECU 215 and the development tool.

[0043] The above are main examples of electronically controlled items of the engine 200, but the actual engine electronic control device 100 also performs controls other than those described above. When the processing load of the engine electronic control device 100 increases, as shown in FIG. 6, the control necessary for the operation of the engine 200 is maintained by reducing the number of control items with low priority. The line indicated by W in FIG. 6 indicates the processing load in the case where all controls are performed as they should be. The line indicated by X in FIG. 6 indicates the processing load in the case where low-priority control suppression is performed to cancel low-priority control when the processing load increases. In the case where the processing load of the engine 200 increases gradually as in the example of FIG. 6, low-priority control suppression that simply reduces the number of control items with low priority is also effective.

[0044] However, in the case of the two-wheeled vehicle 300, there may be cases where the rotation speed of the engine 200 increases suddenly. For example, when overtaking while traveling at high speed, the accelerator 307 is operated to be fully opened to fully open the throttle valve 212 and accelerate, or when fully accelerating in low gear when climbing a slope. In such cases, the rotation speed of the engine 200 increases suddenly, for example, to a high speed of 15,000 revolutions per minute or more. If the rotation speed increases suddenly like this, the processing load cannot be reduced by only the low-priority thinning process. As shown by X in FIG. 6, the low-priority control suppression that simply performs the low-priority thinning process cannot reduce the processing load in the processing load sudden increase region A where the rotation speed of the engine 200 suddenly increases. Therefore, there is a possibility that the processing load will exceed the upper limit Y of the processing capacity (shown in FIG. 7).

[0045] When engine 200 rotates at 15,000 revolutions per minute, the time for one rotation of crankshaft 205 is 4 milliseconds. If the clock frequency of ECU 215 is 80 megahertz, 4 milliseconds is long enough to perform individual controls in engine-based control. However, when engine interrupt control is performed, depending on the interrupt timing, the interrupt processing due to the previously input interrupt signal may not be completed at the time the signal is input, and the interrupt processing may not be able to keep up.

[0046] The present disclosure is characterized by its estimation of the processing load sudden increase region A associated with this sudden increase in the rotation speed of engine 200. That is, the present disclosure is characterized in that the sudden increase in the processing load of engine 200 control is estimated by a different method, rather than the engine-based control described in Fig. 4 or the engine interruption control described in Fig. 5. To repeat, the present disclosure is characterized in that the processing load sudden increase region A of engine 200 is estimated by a different method, on the premise that engine-based control and engine interruption control cannot handle the sudden increase in the processing load of engine 200 control.

[0047] In the present disclosure, the operation of the rider, who is the operator, is directly detected to estimate the processing load sudden increase region A of the engine 200. Specifically, the operation of the accelerator 307 by the rider and the switching of the drive transmission gear 315 are used as input signals to estimate the processing load sudden increase region A of the engine 200. As shown in FIG. 8, in the case of the drive transmission gear 315, the rotation speed of the engine 200 tends to be higher when a low-speed gear is used, so the gear ratio coefficient is made higher for lower-speed gears. Note that FIG. 8 assumes an example in which six gears are used as the drive transmission gear 315. "0" in FIG. 8 is neutral, and the rotation of the engine 200 is not transmitted to the rear wheel 303, which is the drive shaft. "1" is a low-speed gear, and the reduction ratio of the rotation speed from the engine 200 is the largest. Conversely, "6" is a high-speed gear, and the rotation of the engine 200 is not reduced but rather accelerated and transmitted to the final gear that drives the rear wheel 303. In gear "1", which has the largest reduction ratio, the gear ratio coefficient is set to a high value of "2", and as the gear is switched to a higher gear, the gear ratio coefficient decreases. In gear "6", which is the smallest, the gear ratio coefficient is set to "1". Here, the gear ratio coefficient is related to the reduction ratio, but does not indicate the reduction ratio. In other words, the reduction ratio of gear "1" is greater than 2, and the reduction ratio of gear "6" is less than 1.

[0048] The same applies to the opening of the accelerator 307; the greater the accelerator opening, the higher the throttle opening coefficient. An accelerator opening of "0" is idling, where the engine 200 revolutions are at their lowest and the throttle opening coefficient is "1." As the accelerator opening increases, the throttle opening coefficient also increases accordingly, and at "100," which is full throttle, the throttle opening coefficient is set to "2."

[0049] In this embodiment, the processing load sudden increase region A of engine 200 is estimated by the product of the gear ratio coefficient and the throttle opening coefficient. As an example, when the product of the gear ratio coefficient and the throttle opening coefficient is equal to or greater than "2.5", it is estimated that engine 200 will move toward processing load sudden increase region A. For example, when a driver shifts down to "4th" gear during high-speed driving and attempts to overtake with the accelerator opening at full throttle, it can be estimated that engine 200 will move toward processing load sudden increase region A. Similarly, when a driver uses a medium gear "3" on a slope and sets the accelerator opening to "75", it can be estimated that engine 200 will move toward processing load sudden increase region A.

[0050] In addition to the above-mentioned engine base control and engine interrupt control, the engine electronic control device 100 also includes an engine high speed revolution estimation control that estimates that the engine 200 is heading toward the processing load sudden increase region A. Fig. 9 shows control items of the engine high speed revolution estimation control. This engine high speed revolution estimation control is also controlled by an interrupt separately from the engine base control, and the timing of the interrupt is, for example, 1 millisecond.

[0051] The input-related (SIG) control items in the engine high speed revolution estimation control include CAN abnormality detection S9. This CAN abnormality detection S9 detects reception abnormalities and bus off in the CAN (Controller Area Network), which is the communication network of the motorcycle 300, and detects whether there is an abnormality in the transmission of signals from the accelerator sensor 214 and the gear position sensor 316. Other input-related (SIG) control items include accelerator control S10 and gear position control S11. The accelerator control S10 detects how the rider operates the accelerator 307 in response to the signal from the accelerator sensor 214. In the above-mentioned engine base control and engine interrupt control, the signal from the accelerator sensor 214 is used as an output signal to the motor 213 for controlling the opening degree of the throttle valve 212, but in the engine high speed revolution estimation control, it is used to estimate the rider's intention. Similarly, in the gear position control S11, which gear the rider has selected in the drive transmission gear 315 is input as an estimate of the rider's intention.

[0052] The high speed engine revolution estimation control also has a fault diagnosis (DIAG). In this fault diagnosis (DIAG), the accelerator sensor abnormality detection control D5 detects an abnormality in the accelerator sensor 214. In addition, the position sensor abnormality detection control D6 detects an abnormality in the gear position sensor 316. Both of these sensors are essential for the high speed engine revolution estimation control, so they are designed to perform self-diagnosis for faults.

[0053] As described above, the engine high speed revolution estimation control is performed by interrupt control every 1 millisecond, and both the electric signal from the accelerator sensor 214 and the electric signal from the gear position sensor 316 are input to the EUC 215 without delay. Therefore, the rider's intention to move the engine 200 into the processing load sudden increase region A can be estimated at the latest 50 milliseconds after the rider operates the accelerator 307 or the drive transmission gear 315. However, as shown in FIG. 10, it takes about 2 seconds for the engine 200 speed to actually increase from an idling state of 1,000 revolutions per minute to 10,000 revolutions per minute or more. That is, a certain amount of time lag B (shown in FIG. 7 and FIG. 10) occurs from the estimation of the rider's intention until the engine 200 actually reaches the processing load sudden increase region A.

[0054] In this embodiment, the emergency preparation engine control is performed by utilizing this time lag B. As shown in FIG. 4, FIG. 5, and FIG. 9, in the normal engine control, all of the above-mentioned control items are performed. Therefore, when the engine 200 is in the processing load sudden increase region A, it may be difficult to maintain the normal engine control. Therefore, when the engine 200 is in the processing load sudden increase region A, the emergency preparation engine control is performed, and only the items indicated by the circle symbol "○" in the "emergency preparation" item in FIG. 4, FIG. 5, and FIG. 9 are controlled. Since the control items are reduced, the engine 200 can be sufficiently controlled even when it is in the processing load sudden increase region A. The emergency preparation engine control reduces the control items more than the normal engine control, but not as much as the emergency engine control. That is, the number of control items in the emergency preparation engine control is intermediate between the number of items in the normal engine control and the number of items in the emergency engine control.

[0055] In the emergency preparation engine control, the rotation speed of the engine 200 is increasing and the processing load of the ECU 215 is also increasing, but there is still some margin left over the upper limit. Therefore, it is possible to stop control for events that cannot occur at this rotation speed. For example, the stall determination control S2 and the kickback prevention control O4 correspond to these. On the other hand, in the emergency engine control, the rotation speed of the engine 200 is further increasing and the processing load of the ECU 215 is also increasing, so there is no margin left over the upper limit of the processing capacity. Therefore, the number of control items is greatly reduced by restricting them to the so-called basic functions of "running, turning, and stopping."

[0056] In this way, in this embodiment, emergency preparation engine control is performed by utilizing the above-mentioned time lag B, instead of suddenly switching from normal engine control to emergency engine control. This allows the number of control items in the engine control to be gradually reduced, and the engine control can be switched smoothly. In other words, since it is estimated that the rotation speed of the engine 200 will be a high speed rotation speed equal to or higher than a predetermined rotation speed, it is possible to grasp in advance the associated increase in processing load before it exceeds the capacity of the processing load. This makes it possible to suppress unintended processing omissions and the associated change in the driving sensation of the rider.

[0057] Next, switching between normal engine control and emergency engine control will be described with reference to the flowcharts of FIG. 11 and FIG. 12. The flowchart of FIG. 11 is a flow for reducing the number of control items from normal engine control to emergency engine control. Conversely, the flowchart of FIG. 12 is a flow for increasing the number of control items when returning from emergency engine control to normal engine control. Note that while the emergency preparation engine control is treated as one type of control in FIG. 4, FIG. 5, and FIG. 9, the emergency preparation engine control is divided into two types of control in the medium load range and control in the low load range in the flowcharts of FIG. 11 and FIG. 12. The number of control items in the medium load range is greater than the number of control items in the low load range. That is, the number of control items of the engine electronic control device 100 increases in the order of emergency engine control, emergency preparation engine control (medium load), emergency preparation engine control (low load), and normal engine control. In addition, in the flowcharts of FIG. 11 and FIG. 12, the emergency preparation engine control (medium load) is set to mode 2, and the emergency preparation engine control (low load) is set to mode 1.

[0058] FIG. 7 shows the relationship between the time lag B and the processing load when the emergency preparation engine control is divided into mode 2 and mode 1. Line Z1 in FIG. 7 shows mode 1 of the emergency preparation engine control, and line Z2 shows mode 2 of the emergency preparation engine control. In the example of FIG. 7, mode 1 corresponds to the low-load emergency preparation engine control, and mode 2 corresponds to the medium-load emergency preparation engine control. Line Z3 shows the emergency engine control. In the example of FIG. 7, the increase in the processing load is slowed down in mode 1 of the emergency preparation engine control, the processing load is stabilized in mode 2 of the emergency preparation engine control, and the processing load is reduced in the emergency engine control. However, the example of FIG. 7 is only an example, and the increase in the processing load may be eased in mode 1 of the emergency preparation engine control, and the increase in the processing load may be further eased in mode 2 of the emergency preparation engine control, so that the processing load is stabilized in the emergency engine control. In this example, the processing load is set to be about 10% lower than the upper limit Y of the processing capacity when the processing load is stable.

[0059] The flow starts with processing load monitoring process S100 in Fig. 11. As described above, the engine high speed revolution estimation control shown in Fig. 9 is interrupt control every millisecond, and the processing load increase risk (R) is calculated in step S101 based on data obtained by the engine high speed revolution estimation control. This processing load increase risk (R) is a prediction of whether or not the engine 200 will enter the processing load sudden increase region A. As described above, the processing load increase risk (R) is calculated by the product of the gear ratio coefficient and the throttle opening coefficient shown in Fig. 8.

[0060] In step S102, it is determined whether the processing load increase risk (R) is equal to or greater than a specified value. In the example of FIG. 8, it is determined whether the product of the gear ratio coefficient and the throttle opening coefficient is equal to or greater than 2.5. The case where it is equal to or greater than 2.5 (Y) is shown in the flowchart of FIG. 11. In the flowchart of FIG. 11, it is then determined in step S103 whether the current processing load is in a state of emergency preparation engine control at a low load. This is a determination of whether the engine speed shown by "C" in FIG. 10 is less than 6,000 revolutions per minute. If it is determined in step S103 that it is in the low load state C (Y), it is determined whether the state has continued for less than one second (S104).

[0061] If it is less than one second (Y), it is determined that there is no need to switch to emergency preparation engine control yet, and the flow is terminated (S105). In this state, normal engine control continues. If it continues for one second or more (N), the flow is switched to low load control (mode 1) of the emergency preparation engine control (S106). This mode 1 is a control with more control items than the emergency preparation engine control shown in Figs. 4, 5, and 9. For example, in mode 1, all the control items of the engine base control shown in Fig. 4 are performed, and in mode 2, the emergency preparation engine control is performed. For example, in the engine interrupt control shown in Fig. 5, the misfire determination S8 may be performed in mode 1, and the misfire determination S8 may not be performed in mode 2. Then, after switching to low load control (mode 1) (S106), the flow is terminated (S105).

[0062] If in step S103 the current processing load is not the emergency preparation engine control state at a low load (mode 1) (N), then in step S107 it is determined whether the current processing load is the emergency preparation engine control state at a medium load (mode 2). This medium load state (mode 2) is the state indicated by "D" in Fig. 10, where the engine speed is between 6,000 and 9,000 revolutions per minute. If in step S107 it is determined to be in the medium load state D (Y), it is determined whether the state has continued for less than 0.5 seconds (S108).

[0063] If it is less than 0.5 seconds (Y), it is determined that there is no need to transition to the next medium-load emergency preparation engine control, and the flow ends (S105). In this state, the low-load emergency preparation engine control continues. If the state requiring medium-load emergency preparation engine control continues for 0.5 seconds or more (N), the emergency preparation engine control is switched to medium load control (mode 2) (S109), and the flow ends (S105). This mode 2 is set to the same control items as those of the emergency preparation engine control shown in, for example, Figures 4, 5, and 9.

[0064] If the current processing load is not in the emergency preparation engine control state at medium load in step S107 (N), this state should be the emergency engine control state. That is, if the processing load increase risk (R) is equal to or greater than a specified value in step S102, and the engine control is not in the emergency preparation engine control state at low load (S103), or in the emergency preparation engine control state at medium load (S107), it is logically inferred that the engine control will be in the emergency engine control state. However, if the determination in step S110 is No, it is determined that some abnormality exists, and the flow is terminated (S105).

[0065] Normally, the answer in step S110 is Yes. This state is indicated by "E" in FIG. 10, and the engine speed is 9,000 revolutions per minute or more. If the answer in step S110 is Yes, it is determined whether the state continues for less than 0.25 seconds (S108). If it is less than 0.25 seconds (Y), it is determined that there is still no need to switch to emergency engine control, and the flow ends (S105). In this state, medium load emergency preparation engine control (mode 2) continues. If the state requiring emergency engine control continues for 0.25 seconds or more (N), the control switches to emergency engine control (S109), and the flow ends (S105).

[0066] Next, in step S102, it is determined whether the processing load increase risk (R) is equal to or greater than a specified value, and a case in which the result is No will be described with reference to the flowchart in Fig. 12. If the result is No in step S102, it is not estimated from the gear ratio coefficient and the throttle opening coefficient that the processing load increase risk (R) will soon enter the processing load sudden increase region A of the engine 200.

[0067] Even in this state, first, the current processing load state of engine 200 is determined. In step S120, it is determined whether or not the current processing load is in the emergency engine control state. When step S102 determines No and step S120 determines Yes, it is assumed that the state is immediately after the emergency engine control state has ended. Therefore, in step S121, it is determined whether or not the state has continued for less than one second. If it is less than one second (Y), it is desirable to maintain the emergency engine control state for a while longer, and the flow ends as is (S105). If it is not less than one second (N), the emergency engine control state has continued for one second or more, and the flow moves to emergency preparation engine control. In this example, in step S122, the flow moves to mode 2 and ends (S105).

[0068] Next, in step S123, it is determined whether the current processing load is in a medium-load emergency preparation engine control state. If it is determined as No in step S102 and as No in step S120, it is presumed that the emergency engine control state has ended and transitioned to medium-load emergency preparation engine control. Then, in step S124, it is determined whether the state continues for less than 0.5 seconds. If it is less than 0.5 seconds (Y), the medium-load emergency preparation engine control state (mode 2) is maintained for a while longer, and the flow ends as it is (S105). If it is not less than 0.5 seconds (N), the medium-load emergency preparation engine control state (mode 2) has continued for 0.5 seconds or more, so the flow moves to low-load emergency preparation engine control. That is, in step S125, the flow moves to mode 1, and the flow ends (S105).

[0069] Finally, in step S126, it is determined whether the current processing load is a low-load emergency preparation engine control state. If it is determined as No in step S102, No in step S120, and further No in step S123, it is estimated that the emergency engine control state has ended and the state has shifted from the medium-load emergency preparation engine control (mode 2) to the low-load emergency preparation engine control (mode 1). Then, in step S127, it is determined whether the state has continued for less than 0.25 seconds. If it is less than 0.25 seconds (Y), the low-load emergency preparation engine control state (mode 1) is maintained as it is, and the flow ends (S105). If it is not less than 0.25 seconds (N), the low-load emergency preparation engine control state (mode 1) has continued for 0.25 seconds or more, so the flow shifts to normal engine control in step S128 and ends the flow (S105).

[0070] The determination of No in step S126 means that the determinations of No in step S102, No in step S120, and No in step S123 have been made, and the current processing load is not a low-load emergency preparation engine control. In this state, the current state is presumed to be a normal engine control state. Therefore, the flow ends as it is (S105).

[0071] In the flowchart of the above example, the emergency preparation engine control has two stages, mode 1 and mode 2. However, as described above, the emergency preparation engine control may have one stage, or may have three or more stages. Increasing the number of stages makes the transition from normal engine control to emergency engine control smoother, but on the other hand, more precise control is required. An appropriate selection may be made depending on the situation. From the viewpoint of simplifying the control, it is also possible to transition directly from normal engine control to emergency engine control and eliminate the emergency preparation engine control.

[0072] As already mentioned, the examples of control items of the engine electronic control device 100 described above are the main examples, but they are also examples, and other control items may be added, and conversely, some of the control items shown in the embodiments may be deleted.

[0073] In addition, using the engine 200, which is the object of control of the engine electronic control device 100 of the present disclosure, to power the motorcycle 300 is also appropriate in the case of operating the engine 200 at high speed. However, the engine 200 can be widely used as a drive source for three-wheeled buggies, four-wheeled vehicles, and the like other than the motorcycle 300. Furthermore, the engine 200 can be used not only as a drive source for vehicles, but also as an industrial engine if it is used together with the axle 307 and the drive transmission gear 315. [Explanation of symbols]

[0074] 100 Engine Electronic Control Unit 200 Engine 212 Throttle valve 214 Accelerator Sensor 300 Motorcycles 307 Axel 315 Drive transmission gear 316 Gear position sensor

Claims

1. An engine that performs an intake process of air and fuel, a compression process, an ignition / explosion process, and an exhaust process; a throttle valve that varies the amount of intake air to the engine in response to an accelerator pedal operation by an operator; an accelerator sensor that detects an opening degree of the accelerator by an operator; a drive transmission gear that transmits the rotational speed of the engine to a drive shaft and changes the rotational speed transmitted in response to a gear change by an operator; a gear position sensor that detects switching of the drive transmission gear by an operator of the drive transmission gear; an engine electronic control device that electronically controls the rotation of the engine, when the accelerator sensor detects acceleration by an operator and the gear position sensor detects gear switching by the operator, and when it is estimated that the engine speed will be a high speed speed equal to or higher than a predetermined speed, the control of the engine electronic control device is switched from normal engine control to emergency engine control, The emergency engine control of the engine electronic control unit has fewer control items than the normal engine control. An electronic engine control device comprising:

2. the switching of the engine electronic control device from the normal engine control to the emergency engine control is performed in accordance with a gear ratio coefficient based on a gear ratio of the gear detected by the gear position sensor and a throttle opening coefficient based on a throttle opening detected by the accelerator sensor, The gear ratio coefficient is increased as the reduction ratio from the engine to the drive shaft is increased, and the throttle opening coefficient is increased as the opening of the throttle valve is increased.

2. The electronic engine control device according to claim 1.

3. When the product of the gear ratio coefficient and the throttle opening coefficient is equal to or greater than a predetermined threshold value, the engine electronic control device switches from the normal engine control to the emergency engine control.

3. The electronic engine control device according to claim 2.

4. the engine electronic control device performs engine-based control including the engine speed, fuel supply to the engine, and ignition timing to the engine, and engine interrupt control performed in response to the engine speed; When the engine is rotating at a high speed equal to or higher than the predetermined rotation speed, the time for one rotation of the engine is shorter than the time for the engine electronic control device to perform the engine base control and the engine interrupt control.

2. The electronic engine control device according to claim 1.

5. the engine electronic control device performs emergency preparation engine control from an estimation start timing at which it is estimated that the engine speed will be a high speed speed or more to a timing before the engine reaches a high speed speed or more, and performs the emergency engine control at a high speed speed timing after the engine reaches a high speed speed or more, The emergency engine control has fewer control items than the emergency preparation engine control.

2. The electronic engine control device according to claim 1.

6. The emergency preparation engine control is divided into a low-load emergency preparation engine control in which the engine is operating at a low load and a medium-load emergency preparation engine control in which the engine is operating at a medium load, The low-load emergency preparation engine control has fewer control items than the medium-load emergency preparation engine control.

6. The electronic engine control device according to claim 5.

7. In the emergency engine control, only a part of the engine base control and the engine interrupt control is performed.

5. The electronic engine control device according to claim 4.

8. In the emergency engine control, the reduction items in the engine interrupt control are greater than the reduction items in the engine-based control.

8. The electronic engine control device according to claim 4 or 7.

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