JP2024070318A - Engine Control Unit - Google Patents

Abstract

[Problem] To provide an engine control device that can better suppress engine rotation speed while the vehicle is jumping. [Solution] The engine control device includes a rotation speed acquisition unit 50 that acquires engine rotation speed, a speed acquisition unit 52 that acquires wheel speed which is the rotation speed of the wheels of the saddle riding type vehicle, a jump determination unit 60 that determines whether the saddle riding type vehicle has jumped, a rotation speed setting unit 62 that sets an allowable rotation speed which is an allowable value for the engine rotation speed during a jump of the saddle riding type vehicle based on the wheel speed acquired when the saddle riding type vehicle jumps, and a control unit 64 that suppresses an increase in engine rotation speed when the engine rotation speed during a jump of the saddle riding type vehicle reaches the allowable rotation speed. [Selected Figure] Figure 2

Description

The present invention relates to an engine control device that controls the engine speed of a saddle-type vehicle.

When riding a saddle-type vehicle (also called a vehicle), the rider must be careful when passing over bumps on mountain roads.
The vehicle may jump. During the jump, the drive wheels leave the road surface, so the engine is not subjected to road load. This can cause the engine to over-rev and damage the drivetrain components (transmission output shaft, propeller shaft, differential gear, etc.).

Patent document 1 discloses a device that suppresses engine speed when the engine speed exceeds an allowable speed. This device sets an allowable speed that is lower than the normal allowable speed while the vehicle is jumping. In this way, this device prevents the engine from over-revving while the vehicle is jumping.

JP 2008-144685 A

However, it would be preferable to better suppress the engine speed while the vehicle is jumping.

The present invention aims to solve the above-mentioned problems.

An aspect of the present invention is an engine control device that controls the engine speed of a saddle-riding type vehicle, and includes a speed acquisition unit that acquires the engine speed, a speed acquisition unit that acquires a wheel speed that is the rotational speed of the wheels of the saddle-riding type vehicle, a jump determination unit that determines whether the saddle-riding type vehicle has jumped, a speed setting unit that sets an allowable speed that is an allowable value for the engine speed during a jump of the saddle-riding type vehicle based on the wheel speed acquired when the saddle-riding type vehicle jumps, and a control unit that suppresses an increase in the engine speed when the engine speed during a jump of the saddle-riding type vehicle reaches the allowable speed.

The present invention provides an engine control device that can effectively suppress engine speed during vehicle jumps.

FIG. 1 is a configuration diagram of a saddle-type vehicle. FIG. 2 is a functional block diagram of the arithmetic unit. FIG. 3 is a flowchart of the jump determination process. FIG. 4 is a flowchart of the jump end determination process. 5A to 5E are time charts illustrating specific examples of the jump determination process shown in FIG. 3 and the jump end determination process shown in FIG. FIG. 6 is a flowchart of the engine speed suppression control process. 7A to 7E are time charts illustrating an example of the fuel cut control executed in step S26 of FIG. 8A and 8B are time charts illustrating the control of the intake air amount executed while the saddle riding type vehicle is jumping.

If the engine speed is excessively reduced while the saddle-riding vehicle 10 is jumping, there is a risk that the saddle-riding vehicle 10 will decelerate excessively when the saddle-riding vehicle 10 lands. For this reason, it is desirable to appropriately control the engine speed while the saddle-riding vehicle 10 is jumping. The present invention achieves this objective.

[1 Configuration of saddle riding type vehicle 10]
Fig. 1 is a configuration diagram of a saddle-type vehicle 10 (also referred to as vehicle 10). Fig. 2 is a functional block diagram of a computing device 40. The vehicle 10 has a front wheel 12, a rear wheel 14, an engine 16, a power transmission mechanism 18, and an engine control system 20. The output shaft of the engine 16 is connected to the rotating shaft of the rear wheel 14 via the power transmission mechanism 18. In other words, the rear wheel 14 is a driving wheel. The power transmission mechanism 18 has drive system components (transmission output shaft, propeller shaft, differential gear, etc.).

The engine control system 20 controls the operation of the engine 16 based on the detection results of various sensors. The engine control system 20 has a sensor group 22, an engine control device 24, an electronically controlled throttle 26, and a fuel injector 28. The sensor group 22 includes an engine speed sensor 30, a vehicle speed sensor 32, an inertial measurement unit 34 (also called IMU 34), an accelerator position sensor 36, a throttle position sensor 37, and a gear position sensor 38.

The engine speed sensor 30 detects the rotation speed of the engine 16 (engine speed). The vehicle speed sensor 32 detects the rotation speed of the front wheels 12 (wheel speed). The IMU 34 detects the angular velocity and acceleration in three mutually orthogonal axial directions (vertical direction, forward direction, and width direction). The accelerator position sensor 36 detects the accelerator operation amount. The throttle position sensor 37 detects the opening degree of the throttle valve (not shown) of the electronically controlled throttle 26. The gear position sensor 38 detects the gear position. Each sensor outputs the detection result to the engine control device 24 periodically or constantly.

The engine control device 24 has an ECU. The engine control device 24 has a calculation device 40, a storage device 42, and an input/output device (not shown).

The arithmetic device 40 has a processing circuit. The processing circuit may be a processor such as a CPU or a GPU. The processing circuit may be an integrated circuit such as an ASIC or an FPGA. The processor can execute various processes by executing a program stored in the storage device 42. For example, as shown in FIG. 2, the arithmetic device 40 functions as a rotation speed acquisition unit 50, a speed acquisition unit 52, an acceleration acquisition unit 54, an accelerator position acquisition unit 56, a throttle position acquisition unit 57, a gear position acquisition unit 58, a jump determination unit 60, a rotation speed setting unit 62, and a control unit 64. At least some of the multiple processes may be executed by an electronic circuit including a discrete device.

The rotation speed acquisition unit 50 acquires the detection result (engine rotation speed) of the engine rotation speed sensor 30. The speed acquisition unit 52 acquires the detection result (wheel speed) of the vehicle speed sensor 32. The acceleration acquisition unit 54 acquires the detection result (angular velocity and acceleration in each of the three axial directions) of the IMU 34. The accelerator position acquisition unit 56 acquires the detection result (accelerator operation amount) of the accelerator position sensor 36. The throttle position acquisition unit 57 acquires the detection result (throttle valve opening) of the throttle position sensor 37. The gear position acquisition unit 58 acquires the detection result (gear position) of the gear position sensor 38. The jump determination unit 60 determines whether the vehicle 10 is jumping. The rotation speed setting unit 62 sets the allowable rotation speed based on the wheel speed acquired by the speed acquisition unit 52. The allowable rotation speed is the allowable value of the engine rotation speed during the jump of the vehicle 10, and is also a judgment threshold for the control unit 64 to execute fuel cut control during the suppression control process. The control unit 64 executes fuel cut control during suppression control processing to suppress an increase in engine speed when a predetermined first condition is met. In addition, the control unit 64 cancels the fuel cut control during suppression control processing when a predetermined second condition is met during the suppression control processing.

The storage device 42 has a volatile memory and a non-volatile memory. Examples of the volatile memory include RAM. The volatile memory is used as a working memory for the processor. The volatile memory temporarily stores data and the like required for processing or calculation. Examples of the non-volatile memory include ROM and flash memory. The non-volatile memory is used as a storage memory. The non-volatile memory stores programs, tables, maps, and the like. At least a portion of the storage device 42 may be provided in the processor, integrated circuit, and the like as described above.

The electronically controlled throttle 26 has a throttle valve (not shown) and a throttle motor (not shown). The throttle position sensor 37 described above is provided in the electronically controlled throttle 26. The throttle valve adjusts the amount of intake air supplied to the engine 16 by changing the opening area of the intake passage that connects from an air cleaner (not shown) to the engine 16. The throttle motor operates the throttle valve in response to a control signal output from the engine control device 24. The throttle position sensor 37 outputs throttle valve opening information of the electronically controlled throttle 26 to the engine control device 24 as a voltage signal.

The fuel injector 28 is an electronically controlled fuel injection valve. The fuel injector 28 opens and closes an electromagnetic valve in response to an on/off signal output from the engine control device 24, supplying or cutting off fuel to the engine 16.

[2 Operation of the Engine Control Unit 24]
[2-1 Overview of engine control]
When the rear wheels 14, which are driving wheels, spin, the road load on the engine 16 becomes smaller. In particular, no road load is applied to the engine 16 while the vehicle 10 is jumping. This may cause the engine 16 to rotate excessively. The engine control device 24 performs engine control to prevent the engine 16 from over-rotating while the vehicle 10 is traveling. Specifically, the engine control device 24 suppresses an increase in the engine speed when the engine speed exceeds the allowable speed, which is the upper limit of the allowable speed. In this specification, this control is referred to as fuel cut control.

The rotation speed setting unit 62 of the engine control device 24 switches the permissible rotation speed to the permissible rotation speed for jumping when the vehicle 10 transitions from a state in which the vehicle 10 is traveling on a road surface to a state in which the vehicle 10 is jumping. Also, the rotation speed setting unit 62 switches the permissible rotation speed to the permissible rotation speed for normal use when the vehicle 10 transitions from a state in which the vehicle 10 is jumping to a state in which the vehicle 10 is traveling on a road surface.

[2-2 Jump Judgment Processing, Jump End Judgment Processing]
FIG. 3 is a flowchart of the jump determination process. FIG. 4 is a flowchart of the jump end determination process. The jump determination unit 60 sets the jump determination flag to 0 or 1 depending on the state of the vehicle 10. When the vehicle 10 is started, the jump determination flag is 0. When the vehicle 10 has not jumped (when the jump determination flag = 0), the jump determination unit 60 performs the jump determination process shown in FIG. 3. The jump determination unit 60 performs the jump determination process to determine whether or not the vehicle 10 has jumped. When the vehicle 10 has jumped (when the jump determination flag = 1), the jump determination unit 60 performs the jump end determination process shown in FIG. 4. The jump determination unit 60 performs the jump end determination process to determine whether or not the jump of the vehicle 10 has ended. The jump determination unit 60 performs either the jump determination process or the jump end determination process at a predetermined cycle.

In step S1 shown in FIG. 3, the jump determination unit 60 determines whether the jump condition is satisfied. The jump condition is a condition for determining whether the vehicle 10 is jumping. The jump determination unit 60 determines that the first jump condition is satisfied when the vertical acceleration acquired by the acceleration acquisition unit 54 reaches a first range defined by a predetermined upper limit value and a predetermined lower limit value. The jump determination unit 60 also determines that the second jump condition is satisfied when the acceleration in the traveling direction acquired by the acceleration acquisition unit 54 reaches a second range defined by a predetermined upper limit value and a predetermined lower limit value. The upper limit value of the vertical acceleration is different from the upper limit value of the traveling direction acceleration. Similarly, the lower limit value of the vertical acceleration is different from the lower limit value of the traveling direction acceleration. The upper limit value and the lower limit value of the vertical acceleration and the upper limit value and the lower limit value of the traveling direction acceleration are each pre-stored in the storage device 42. The jump determination unit 60 determines that the jump condition is satisfied when both the first jump condition and the second jump condition are satisfied. If the jump condition is satisfied (step S1: YES), the process proceeds to step S3. On the other hand, if the jump condition is not satisfied (step S1: NO), the process proceeds to step S2.

When moving from step S1 to step S2, the jump determination unit 60 sets the jump determination flag to 0. In other words, the jump determination unit 60 maintains the jump determination flag at 0. When step S2 ends, the jump determination process for this cycle ends. After this, the jump determination unit 60 continues to perform the jump determination process.

When moving from step S1 to step S3, the jump determination unit 60 performs timing using a jump determination timer provided in the calculation device 40.

In step S4, the jump determination unit 60 determines whether the time measured by the jump determination timer has reached a predetermined first time threshold. The first time threshold is a threshold for determining whether the vehicle 10 has jumped. The first time threshold is pre-stored in the storage device 42. If the measured time has reached the first time threshold (step S4: YES), the process proceeds to step S5. On the other hand, if the measured time has not reached the first time threshold (step S4: NO), the process returns to step S1.

When moving from step S4 to step S5, the jump judgment unit 60 judges that the vehicle 10 has jumped. That is, the jump judgment unit 60 detects a jump of the vehicle 10 when the time measured by the jump judgment timer (the period during which the jump condition is satisfied) reaches the first time threshold. When the jump judgment unit 60 detects a jump of the vehicle 10, it sets the jump judgment flag to 1. When step S5 ends, the jump judgment process for this cycle ends.

The jump determination unit 60 performs steps S3 and S4 in order to reduce erroneous jump determinations.

In step S11 shown in FIG. 4, the jump determination unit 60 determines whether the jump end condition is satisfied. The jump determination unit 60 determines that the first jump end condition is satisfied when the vertical acceleration acquired by the acceleration acquisition unit 54 has not reached a first range defined by a predetermined upper limit value and a predetermined lower limit value. The jump determination unit 60 also determines that the second jump end condition is satisfied when the forward acceleration acquired by the acceleration acquisition unit 54 has not reached a second range defined by a predetermined upper limit value and a predetermined lower limit value. The jump determination unit 60 determines that the jump end condition is satisfied when either the first jump end condition or the second jump end condition is satisfied. When the jump end condition is satisfied (step S11: YES), the process proceeds to step S13. On the other hand, when the jump end condition is not satisfied (step S11: NO), the process proceeds to step S12.

When moving from step S11 to step S12, the jump determination unit 60 sets the jump determination flag to 1. In other words, the jump determination unit 60 maintains the jump determination flag at 1. When step S12 ends, the jump end determination process for this cycle ends. After this, the jump determination unit 60 continues to perform the jump end determination process.

When the process moves from step S11 to step S13, the jump determination unit 60 performs timing using a jump end determination timer provided in the calculation device 40.

In step S14, the jump determination unit 60 determines whether the measured time of the jump end determination timer has reached a predetermined second time threshold. The second time threshold is a threshold for determining whether the jump of the vehicle 10 has ended. The second time may be the same as the first time threshold, or may be different. The second time threshold is pre-stored in the storage device 42. If the measured time has reached the second time threshold (step S14: YES), the process proceeds to step S15. On the other hand, if the measured time has not reached the second time threshold (step S14: NO), the process returns to step S11.

When moving from step S14 to step S15, the jump determination unit 60 determines that the jump of the vehicle 10 has ended. That is, the jump determination unit 60 detects the end of the jump of the vehicle 10 when the measured time of the jump end determination timer (the period during which the jump end condition is satisfied) reaches the second time threshold. When the jump determination unit 60 detects the end of the jump of the vehicle 10, it sets the jump determination flag to 0. When step S15 ends, the jump end determination process for this cycle ends.

The jump determination unit 60 performs steps S13 and S14 in order to reduce erroneous determinations of the end of the jump.

Figures 5A to 5E are time charts used to explain specific examples of the jump judgment process shown in Figure 3 and the jump end judgment process shown in Figure 4. Figure 5A is a time chart showing the change over time in the acceleration of the vehicle 10 in the vertical direction. Figure 5B is a time chart showing the change over time in the acceleration of the vehicle 10 in the traveling direction. Figure 5C is a time chart showing the change over time in the jump judgment timer. Figure 5D is a time chart showing the change over time in the jump end judgment timer. Figure 5E is a time chart showing the change over time in the jump judgment flag.

At time ta1, the vertical acceleration reaches a first range defined by an upper limit and a lower limit, and the forward acceleration reaches a second range defined by an upper limit and a lower limit. Therefore, the jump determination unit 60 starts timing using the jump determination timer at time ta1.

Between time ta1 and time ta2, the vertical acceleration is maintained within a first range defined by an upper limit value and a lower limit value, and the acceleration in the forward direction is maintained within a second range defined by an upper limit value and a lower limit value. At time ta2, the time measured by the jump judgment timer reaches the first time threshold. This causes the jump judgment unit 60 to detect a jump of the vehicle 10. The jump judgment unit 60 sets the jump judgment flag to 1.

At time ta3, the vertical acceleration exceeds the upper limit and falls outside the first range. At time ta3, the jump determination unit 60 starts timing using the jump end determination timer.

Between time ta3 and time ta4, the vertical acceleration is equal to or greater than the upper limit and is maintained outside the first range. At time ta4, the time measured by the jump end determination timer reaches the second time threshold. As a result, the jump determination unit 60 detects that the jump of the vehicle 10 has ended. The jump determination unit 60 sets the jump determination flag to 0.

[2-3 Engine Revolution Speed Suppression Control Processing]
Fig. 6 is a flow chart of the engine speed suppression control process. The suppression control process in the process of Fig. 6 is a process for determining whether or not to cut off fuel supply to the engine 16 in order to suppress an increase in the engine speed when the engine speed reaches the allowable speed. In other words, the suppression control process is a process for determining whether or not to execute fuel cut control. The engine control device 24 performs the engine speed suppression control process shown in Fig. 6 at a predetermined cycle in parallel with the jump determination process shown in Fig. 3 or the jump end determination process shown in Fig. 4. The engine control device 24 performs engine control using a jump determination flag set by the jump determination process and the jump end determination process.

In step S21, the rotation speed setting unit 62 determines whether one or more switching conditions for the allowable rotation speed are satisfied. The one or more switching conditions include the condition "jump determination flag = 1 (vehicle 10 is jumping)." The multiple switching conditions may include the condition "the gear position acquired by the gear position acquisition unit 58 is within a predetermined position range." The multiple switching conditions may also include the condition "the wheel speed at the time of jump detection acquired by the speed acquisition unit 52 is within a predetermined speed range." If all switching conditions are satisfied (step S21: YES), the process proceeds to step S22. On the other hand, if any switching condition is not satisfied (step S21: NO), the process proceeds to step S24.

When the process moves from step S21 to step S22, the rotation speed setting unit 62 acquires the allowable rotation speed for the jump of the vehicle 10. First, the rotation speed setting unit 62 determines an appropriate rotation speed based on the wheel speed of the front wheels 12 at the time of jump detection. The appropriate rotation speed is an engine rotation speed suitable for the speed of the vehicle 10 at the time of landing. The rotation speed setting unit 62 may determine the appropriate rotation speed using a predetermined table, or may calculate the appropriate rotation speed using a predetermined arithmetic expression. Next, the rotation speed setting unit 62 calculates the allowable rotation speed by adding the predetermined rotation speed to the appropriate rotation speed. As will be described later, when the engine rotation speed is limited to or below the allowable rotation speed, excessive acceleration and excessive deceleration do not occur in the vehicle 10 at the time of landing.

The rotation speed setting unit 62 may set a certain range, or so-called hysteresis, for the allowable rotation speed. In this case, a first rotation speed and a second rotation speed (<first rotation speed) are set as the predetermined rotation speed. The rotation speed setting unit 62 calculates the upper limit of the allowable rotation speed by adding the first rotation speed to the appropriate rotation speed. The rotation speed setting unit 62 also calculates the lower limit of the allowable rotation speed by adding the second rotation speed to the appropriate rotation speed.

The rotation speed setting unit 62 may determine the predetermined rotation speed (first rotation speed and second rotation speed) according to the gear position acquired by the gear position acquisition unit 58 when the vehicle 10 jumps. The relationship between the gear position and the predetermined rotation speed is preferably stored in advance in the storage device 42. By determining the predetermined rotation speed according to the gear position, the allowable rotation speed becomes a more appropriate value. The predetermined rotation speed may be a constant value. Instead of performing the above calculations, the rotation speed setting unit 62 may determine the allowable rotation speed using a table or map that defines the relationship between the wheel speed, the gear position, and the allowable rotation speed.

In step S23, the rotation speed setting unit 62 sets the permissible rotation speed for the jump obtained in step S22 as the permissible rotation speed to be used in the next step S25.

When the process moves from step S21 to step S24, the rotation speed setting unit 62 sets the normal allowable rotation speed as the allowable rotation speed to be used in the next step S25. As with the allowable rotation speed for jumping the vehicle 10, the rotation speed setting unit 62 may set a certain range, so-called hysteresis, for the normal allowable rotation speed. The normal allowable rotation speed is stored in the storage device 42.

When the process proceeds from either step S23 or step S24 to step S25, the control unit 64 compares the current engine speed acquired by the speed acquisition unit 50 with the allowable speed set by the speed setting unit 62. If the engine speed is equal to or greater than the allowable speed (step S25: YES), the process proceeds to step S26. On the other hand, if the engine speed is less than the allowable speed (step S25: NO), the process proceeds to step S27.

When the process moves from step S25 to step S26, the control unit 64 executes fuel cut control. As fuel cut control, the control unit 64 controls the fuel injector 28 to reduce the engine speed. When step S26 ends, the engine speed suppression control process for this cycle ends.

When the process moves from step S25 to step S27, the control unit 64 does not execute fuel cut control. When step S27 ends, the engine speed suppression control process for this cycle ends.

[2-4 Suppression control process (fuel cut)]
Figures 7A to 7E are time charts illustrating an example of fuel cut control executed in step S26 of Figure 6. Figure 7A is a time chart showing the change over time of a jump determination flag. Figure 7B is a time chart showing the change over time of a gear position. Figure 7C is a time chart showing the wheel speed of the front wheels 12. Figure 7D is a time chart showing the change over time of the engine speed. Note that Figure 7D is a time chart in the case where hysteresis is set in the permissible speed. Figure 7E is a time chart showing the execution state of fuel cut control.

At time tb1, the jump determination unit 60 sets the jump determination flag to 1. That is, the jump determination unit 60 determines that the vehicle 10 is jumping. Also, at time tb1, the gear position is within a predetermined position range. Also, at time tb1, the wheel speed of the front wheels 12 is within a predetermined speed range. Therefore, at time tb1, the rotation speed setting unit 62 sets the permissible rotation speeds (first rotation speed and second rotation speed) for the jump.

At time tb2, the engine speed becomes equal to or exceeds the upper limit (first speed) of the allowable speed for jumping. At this timing, the control unit 64 executes fuel cut control as a suppression control process. While fuel cut control is being executed, the control unit 64 turns off the pulse signal output to the fuel injector 28. As a result, fuel is not supplied to the engine 16 regardless of the rider's accelerator operation. Therefore, the increase in engine speed is suppressed compared to a state where fuel cut control is not executed.

At time tb3, the engine speed falls below the lower limit of the allowable speed for jumping (second speed). The control unit 64 stops the fuel cut control at this timing. As a result, the control unit 64 supplies fuel to the engine 16 in response to the rider's accelerator operation.

The control unit 64 executes fuel cut control at time tb4 and stops fuel cut control at time tb5.

[2-5 Control of intake air volume]
Figures 8A and 8B are time charts explaining the control of the intake air amount executed during a jump of the saddle riding type vehicle 10. Figure 8A is a time chart showing the change over time of a jump determination flag. Figure 8B is a time chart showing the change over time of the throttle opening degree of the electronically controlled throttle 26. During a jump of the vehicle 10, the control unit 64 may suppress the amount of intake air supplied to the engine 16 by controlling the electronically controlled throttle 26, separately from the fuel cut control.

At time tc1, the jump determination unit 60 sets the jump determination flag to 1. That is, the jump determination unit 60 determines that the vehicle 10 is jumping. The jump determination flag becoming 1 triggers the control unit 64 to set the opening degree (throttle opening degree) of the electronically controlled throttle 26 to the requested opening degree at the time of jump determination, which is the opening degree (requested opening degree) requested by the rider that is reduced from that of normal control.

When the control unit 64 does not determine that the vehicle 10 is jumping, it outputs a control signal to the throttle motor according to the deviation between the requested opening calculated from the map data for normal use and the throttle opening, based on the accelerator operation amount acquired by the accelerator position acquisition unit 56 and the engine speed acquired by the rotation speed acquisition unit 50. When the jump determination flag becomes 1, the control unit 64 switches the map to be used from the normal map to the map for jumping. Based on the accelerator operation amount acquired by the accelerator position acquisition unit 56 and the engine speed acquired by the rotation speed acquisition unit 50, the control unit 64 outputs a control signal to the throttle motor according to the deviation between the requested opening at the time of jump determination calculated from the map data for jumping and the throttle opening. Note that a smaller value is set in the map data for jumping compared to the map data for normal use so that the requested opening at the time of jump determination is smaller than the requested opening. As a result, the throttle opening in the suppression control process is smaller than the throttle opening in the normal control. As a result, even if the rider increases the amount of accelerator pedal operation during a jump, the amount of intake air supplied to the engine 16 is reduced compared to the normal intake air amount.

At time tc2, the jump determination unit 60 sets the jump determination flag to 0. That is, the jump determination unit 60 determines that the jump of the vehicle 10 has ended. The fact that the jump determination flag has become 0 triggers the control unit 64 to return the throttle opening to the requested opening. If the throttle opening is returned to the requested opening at time tc2, a large load is applied to the power transmission mechanism 18. Therefore, in this embodiment, the control unit 64 gradually brings the throttle opening closer to the requested opening. For example, as shown in FIG. 8B, the control unit 64 increases the throttle opening in stages to bring it closer to the requested opening. Alternatively, the control unit 64 may continuously increase the throttle opening at a constant rate of change to bring it closer to the requested opening. This makes it possible to reduce the load on the power transmission mechanism 18 when the vehicle 10 lands.

[3 Modifications]
In the above embodiment, the control unit 64 performs the fuel cut control described in [2-4] above as the suppression control process, and controls the intake air amount described in [2-5] above separately from the suppression control process. Alternatively, the control unit 64 may perform the fuel cut control as the suppression control process, and may not control the intake air amount. The control unit 64 may also control the intake air amount as the suppression control process.

In the above-described embodiment, the jump determination unit 60 determines whether or not the vehicle 10 will jump based on the vertical acceleration and the acceleration in the traveling direction of the vehicle 10. Alternatively, the jump determination unit 60 may determine whether or not the vehicle 10 will jump based on the load applied to the suspension or the amount of expansion and contraction of the suspension, etc.

In the jump determination process shown in FIG. 3, the jump determination unit 60 determines that the vehicle 10 has jumped when the first time threshold has elapsed since the jump condition was satisfied. Alternatively, the jump determination unit 60 may determine that the vehicle 10 has jumped when the jump condition was satisfied (step S1: YES). In this case, steps S3 and S4 are not necessary.

In the jump end determination process shown in FIG. 4, the jump determination unit 60 determines that the jump of the vehicle 10 has ended when the second time threshold has elapsed since the jump end condition was satisfied. Alternatively, the jump determination unit 60 may determine that the jump of the vehicle 10 has ended when the jump end condition was satisfied (step S11: YES). In this case, steps S13 and S14 are unnecessary.

The speed acquisition unit 52 may acquire the wheel speed of the rear wheels 14 instead of the wheel speed of the front wheels 12.

[4. Invention Obtained from the Embodiments]
The invention that can be understood from the above embodiment will be described below.

An aspect of the present invention is an engine control device (24) that controls the engine speed of a saddle riding type vehicle (10), and includes a speed acquisition unit (50) that acquires the engine speed, a speed acquisition unit (52) that acquires a wheel speed that is the rotational speed of the wheels of the saddle riding type vehicle, a jump determination unit (60) that determines whether the saddle riding type vehicle has jumped, a speed setting unit (62) that sets an allowable speed that is an allowable value of the engine speed during the jump of the saddle riding type vehicle based on the wheel speed acquired when the saddle riding type vehicle jumps, and a control unit (64) that suppresses an increase in the engine speed when the engine speed during the jump of the saddle riding type vehicle reaches the allowable speed.

In the above configuration, suppression control processing is executed to suppress an increase in engine speed while the vehicle is jumping. Therefore, with the above configuration, it is possible to suppress over-revving of the engine, and to suppress sudden acceleration of the vehicle when the vehicle lands. Furthermore, with the above configuration, the load on the drive system components is reduced, and damage to the drive system components can be prevented. Moreover, with the above configuration, a judgment threshold (allowable rotation speed) for determining whether or not to execute suppression control processing for the engine speed is set based on the wheel speed obtained at the time the vehicle jumps. In other words, a judgment threshold is set according to the state of the jump. Therefore, with the above configuration, it is possible to suppress excessive deceleration of the vehicle when the vehicle lands.

In one aspect of the present invention, the speed acquisition unit may acquire the wheel speed of the front wheel (12) of the saddle-type vehicle.

The rear wheels, which are the driving wheels, may spin when in contact with the road surface. For this reason, the rotation speed of the rear wheels tends to be higher than the rotation speed of the front wheels. With the above configuration, the wheel speed of the front wheels is used to perform the suppression control process, so the suppression control process can be performed more accurately.

In one aspect of the present invention, the rotation speed setting unit may determine an appropriate engine rotation speed suitable for the speed of the saddle-type vehicle when landing based on the wheel speed obtained when the saddle-type vehicle jumps, and calculate the allowable rotation speed by adding a predetermined rotation speed to the appropriate rotation speed.

According to the above configuration, the engine speed of the vehicle when landing is set to a predetermined number of revolutions higher than the appropriate speed, so that over-revving of the engine can be suppressed. Furthermore, according to the above configuration, the speed of the vehicle when landing can be made appropriate.

In one aspect of the present invention, a gear position acquisition unit (58) may be further provided to acquire the gear position of the saddle-type vehicle, and the rotation speed setting unit may set the predetermined rotation speed according to the gear position acquired when the saddle-type vehicle jumps.

The above configuration allows the vehicle speed to be more appropriate when the vehicle lands.

The present invention is not limited to the above disclosure, and various configurations may be adopted without departing from the gist of the present invention.

REFERENCE SIGNS LIST 10 saddle-ride type vehicle, vehicle 12 front wheel 24 engine control device 50 rotation speed acquisition section 52 speed acquisition section 54 acceleration acquisition section 58 gear position acquisition section 60 jump determination section 62 rotation speed setting section 64 control section

Claims (4)

An engine control device for controlling an engine speed of a saddle-type vehicle,
A rotation speed acquisition unit that acquires the engine rotation speed;
a speed acquisition unit that acquires a wheel speed, which is a rotation speed of a wheel of the saddle riding type vehicle;
a jump determination unit that determines whether the saddle riding type vehicle has jumped;
a rotation speed setting unit that sets an allowable rotation speed, which is an allowable value of the engine rotation speed during a jump of the saddle riding type vehicle, based on the wheel speed obtained when the saddle riding type vehicle jumps;
a control unit that suppresses an increase in the engine rotation speed when the engine rotation speed during a jump of the saddle riding type vehicle reaches the permissible rotation speed;
An engine control device comprising: 2. The engine control device according to claim 1,
The speed acquisition unit acquires the wheel speed of a front wheel of the saddle riding type vehicle. 3. The engine control device according to claim 2,
The engine control device, wherein the rotation speed setting unit determines an appropriate engine rotation speed suitable for the speed of the saddle-type vehicle at the time of landing based on the wheel speed obtained when the saddle-type vehicle jumps, and calculates the permissible rotation speed by adding a predetermined rotation speed to the appropriate rotation speed. 4. The engine control device according to claim 3,
A gear position acquisition unit that acquires a gear position of the saddle riding type vehicle is further provided,
The engine control device, wherein the rotation speed setting unit sets the predetermined rotation speed in accordance with the gear position obtained when the saddle riding type vehicle jumps.

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