Vehicle control system

Abstract

To provide a vehicle control device having improved performance property in a circuit mode.SOLUTION: A vehicle control device includes: a mode determination part that determines whether or not a travel mode of a vehicle is switched to a circuit mode; and a start sound control part that, in a case of affirmative determination by the mode determination part, executes start sound increase processing of increasing start sound of a travel power source of the vehicle more than that in a case of negative determination by the mode determination part.SELECTED DRAWING: Figure 2

Description

[[Technical Field]]

[0001] The present invention relates to a vehicle control device. [[Background Art]]

[0002] There are vehicles that can switch a travel mode to a circuit mode (see, for example, Patent Document 1). [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Application Publication No. 2015-199382 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] When the travel mode is switched to the circuit mode, there is a demand for a performance effect that produces a difference between other modes and the circuit mode.

[0005] Accordingly, an object of the present invention is to provide a vehicle control device with improved performance effect in the circuit mode. [[Means for Solving the Problem]]

[0006] The above object is achieved by: a mode determination unit that determines whether a travel mode of a vehicle has been switched to Circuit Mode ; and a starting sound control unit that executes starting sound increasing processing for increasing a starting sound of a travel power source of the vehicle when an affirmative determination is made by the mode determination unit, compared to when a negative determination is made by the mode determination unit The driving power source is an engine, and when the mode determination unit makes a positive determination, the starting sound control unit performs the starting sound amplification process by increasing the engine speed at startup compared to when the mode determination unit makes a negative determination, and when the engine speed in idle operation is higher than a fuel cut speed that is higher than the target idle speed, the fuel cut control unit performs the engine fuel cut process, and while the starting sound amplification process is being performed, the fuel cut control unit sets the fuel cut speed to a higher value than when the starting sound amplification process is stopped, and when the engine torque is at a predetermined base The system includes an abnormality determination unit that determines that an abnormality has occurred in the engine when the reference value is higher than a predetermined value or more, the reference value is set to the torque of the engine during the execution of the starting sound amplification process when the engine is functioning normally, and the starting sound control unit executes the starting sound amplification process when the conditions are met, including the vehicle being stationary, the accelerator opening being zero, and the shift range being in the N range, and the reference value is a value that fluctuates in accordance with the change in the torque of the engine during the execution of the starting sound amplification process when the engine is functioning normally, and is set by referring to a map corresponding to the engine speed during the execution of the starting sound amplification process. in the vehicle control device.

[0010] The starting sound control unit may stop the starting sound increasing processing after a predetermined time has elapsed since the starting sound increasing processing was started. [[Effect of the Invention]]

[0011] According to the present invention, it is possible to provide a vehicle control device that enhances the performance in circuit mode. [Brief explanation of the drawing]

[0012] [Figure 1] This is a schematic diagram of the vehicle's configuration. [Figure 2] This is a flowchart illustrating the control of the visual effects. [Figure 3] This is a timing chart illustrating the control of the performance. [Modes for carrying out the invention]

[0013] [Vehicle Outline] Figure 1 is a schematic diagram showing the general configuration of vehicle 1. Vehicle 1 is equipped with an engine (ENG) 10, a torque converter (T / C) 12, and an automatic transmission (A / T) 14. The engine 10 is a gasoline engine, but it may also be a diesel engine. The engine 10 is started by cranking with a starter 9. The torque converter 12 is connected to the crankshaft 11 of the engine 10. The turbine shaft 13 of the torque converter 12 is connected to the input side of the automatic transmission 14, and the driving force of the engine 10 is transmitted to the automatic transmission 14. The output shaft 15 of the automatic transmission 14 is connected to a differential gear 16, which is the final reduction gear. The left and right axles 17 are connected to the differential gear 16. The driving force transmitted to the output shaft 15 is transmitted to the drive wheels 18 via the axles 17.

[0014] The automatic transmission 14 is a stepped transmission and includes a plurality of hydraulic friction engagement elements and a planetary gear system. In the automatic transmission 14, the plurality of friction engagement elements are selectively engaged to switch between P (parking), R (reverse), N (neutral), and D (drive) ranges.

[0015] The ECU (Electronic Control Unit) 20 is an electronic control unit that performs control processing related to the vehicle 1. The ECU 20 is a computer that includes a CPU (Central Processing Unit), RAM (Random Access Memory), and ROM (Read Only Memory). The ECU 20 is an example of a vehicle control device and functionally implements the mode determination unit, starting sound control unit, fuel cut control unit, and abnormality determination unit, which will be described in more detail later.

[0016] The ECU20 is connected to a crank angle sensor 21, a shift position sensor 22, an air flow meter 23, an accelerator pedal position sensor 24, a mode selector switch 25, and a vehicle speed sensor 26. The crank angle sensor 21 detects the engine speed. The shift position sensor 22 detects the position of the shift lever. The air flow meter 23 detects the amount of intake air for the engine 10. The accelerator pedal position sensor 24 detects the accelerator pedal position, which is the degree to which the accelerator pedal is opened. The mode selector switch 25 can switch between driving modes, which will be described later. The vehicle speed sensor 26 detects the vehicle speed.

[0017] The ECU 20 calculates the required torque and target rotational speed for the engine 10 based on the engine speed, intake air volume, and accelerator opening detected by the above-mentioned sensors. The ECU 20 controls the fuel injection amount, intake air volume, and ignition timing according to the required torque and target rotational speed. For example, when the engine 10 is idling, the ECU 20 controls the fuel injection amount, intake air volume, and ignition timing so that the engine speed becomes the target idle speed and the engine torque becomes the supplied torque.

[0018] The ECU 20 can switch the driving mode to one of the following: Normal mode, Sport mode, Eco mode, or Circuit mode. The driver can switch the driving mode to Normal mode, Sport mode, or Eco mode by operating the mode selector switch 25. For Circuit mode, for example, if Vehicle 1 is at a race track, the driver can switch the driving mode to Circuit mode by operating a mobile device such as a smartphone. When the driving mode is switched to Circuit mode, the control map of Vehicle 1 is switched to a control map that prioritizes driving performance corresponding to Circuit mode. As a result, the driving performance of Vehicle 1 is improved compared to driving modes other than Circuit mode. Note that switching to Circuit mode may also be done using the mode selector switch 25 as described above.

[0019] The ECU 20 performs a fuel cut process to stop fuel injection to the engine 10 when predetermined conditions are met. Specifically, the ECU 20 performs the fuel cut process for the engine 10 when the engine speed exceeds the fuel cut speed. The fuel cut speed is set to a value higher than the target idle speed. This improves fuel efficiency. Fuel cut is also performed during idle operation. The fuel cut process is an example of a process performed by the fuel cut control unit.

[0020] [Performance control] Figure 2 is a flowchart illustrating the performance control. This control continues and is repeated as long as the ignition is on. The ECU 20 determines whether the driving mode has been switched to circuit mode (step S1). If the result in step S1 is No, this control ends. Step S1 is an example of the process executed by the mode determination unit. If the result in step S1 is Yes, the ECU 20 determines whether there is a request to start the engine 10 (step S2). If the result in step S2 is No, this control ends.

[0021] If the determination is Yes in step S2, it is determined whether a precondition for executing the starting sound increasing process described below is satisfied (step S3). The precondition is, for example, that the vehicle is in a stopped state, the accelerator opening is zero, and the shift range is the N range. As will be described in detail later, in the starting sound increasing process, the revving rotation speed when starting the engine 10 is increased. By executing the starting sound increasing process when the above precondition is satisfied, safety is ensured. If the determination is No in step S3, the present control ends.

[0022] If the determination is Yes in step S3, the ECU 20 executes a starting process of the engine 10 (step S4), and executes the starting sound increasing process (step S5). The starting process is a process in which the starter 9 cranks the engine 10, and fuel injection is started when the engine rotation speed becomes equal to or higher than a predetermined value. The starting sound increasing process is a process of increasing the starting sound of the engine 10 compared to when the traveling mode is not the circuit mode. Specifically, the starting sound is increased by increasing the revving rotation speed when starting the engine 10. The revving rotation speed is the engine rotation speed that rises above the target idle rotation speed immediately after the engine 10 is started. An increase in the revving rotation speed is achieved by increasing the throttle opening at the time of starting and increasing the fuel injection amount compared to when the traveling mode is not the circuit mode. Since the starting sound of the engine 10 is loud in this way, the performance effect of the circuit mode is improved. Step S5 is an example of processing executed by the starting sound control unit.

[0023] Next, the ECU 20 sets the aforementioned fuel cut rotation speed to a higher value during execution of the starting sound increasing process than when the starting sound increasing process is stopped (step S6). During execution of the starting sound increasing process, the revving rotation speed increases as described above. Since the fuel cut rotation speed is set to a high value during execution of the starting sound increasing process, it is suppressed that the revving rotation speed during execution of the starting sound increasing process becomes equal to or higher than the fuel cut rotation speed and the fuel cut process is executed. Step S6 is an example of processing executed by the fuel cut control unit.

[0024] Next, the ECU 20 determines whether or not the engine torque is higher than a predetermined reference value by a predetermined threshold or more (step S7). The reference value is set to the engine torque occurring when the engine 10 is normal and the startup sound increasing process is being executed. The reference value is obtained in advance through experiments and stored in the ROM of the ECU 20. Note that the engine torque may be calculated, for example, based on the intake air amount detected by the air flow meter 23, or may be detected by a torque sensor. Step S7 is an example of processing executed by the abnormality determination unit.

[0025] If the determination in step S7 is No, next the ECU 20 determines whether or not a predetermined time has elapsed from the start of the startup sound increasing process (step S8). If the determination in step S8 is No, the processing from step S5 onward is executed again.

[0026] If the determination in step S8 is Yes, the ECU 20 stops the startup sound increasing process (step S9). As described above, in the startup sound increasing process, the revving speed of the engine 10 at startup is increased. For this reason, in consideration of safety, the startup sound increasing process is stopped. Note that when the startup sound increasing process is stopped, the aforementioned fuel cut rotation speed and reference value are restored to their original lower values.

[0027] If the determination in step S7 is Yes, the ECU 20 determines that an abnormality has occurred in the engine 10 (step S10), and executes processing for ensuring safety (step S11). The processing for ensuring safety includes, for example, processing of stopping the startup sound increasing process and limiting the vehicle speed, processing of forcibly stopping the engine 10, and the like. Step S10 is an example of processing executed by the abnormality determination unit.

[0028] Figure 3 is a timing chart illustrating the control of the sound effects. Figure 3 shows the changes in the starter drive state, engine speed, on / off state of the starting sound amplification processing flag, throttle opening, and engine torque. Figure 3 also shows the reference values ​​for determining abnormalities in engine 10 during the execution of the starting sound amplification processing described above. Figure 3 also shows the changes in ISC required torque. ISC required torque is the engine torque required for the engine speed to converge to the target idle speed.

[0029] When a request to start engine 10 is received in circuit mode, the starter 9 is activated (time t1), and the engine speed begins to increase (time t2). Subsequently, the start sound amplification processing flag is switched on, the throttle opening is increased by a predetermined amount, combustion begins, and torque increases (time t3). After that, the starter 9 stops (time t4). Engine torque begins to increase further (time t5).

[0030] When the engine speed exceeds a predetermined number of termination judgments, the starting sound amplification processing flag is switched off, the throttle opening is reduced to its original opening, and the torque decreases (time t6). During the execution of the starting sound amplification processing, the fuel cut speed is set to a value higher than the number of termination judgments. After that, the engine torque converges to the ISC-required torque, and the engine speed converges to the target idle speed. In this way, the starting sound amplification processing stops after a predetermined time has elapsed as described above. That is, in this embodiment, when the engine speed exceeds a predetermined number of termination judgments, it is considered that a predetermined time has elapsed since the start of the starting sound amplification processing, and the starting sound amplification processing stops. Alternatively, the time since the starting sound amplification processing flag was switched on may be measured, and the starting sound amplification processing may be stopped when a predetermined time has elapsed.

[0031] As shown in Figure 3, during the execution of the startup noise amplification process, the reference value fluctuates in accordance with the normal engine torque. For example, if the engine torque becomes higher than a predetermined value relative to the ISC-required torque during the execution of the startup noise amplification process, it is conceivable that an abnormality has occurred in the engine 10. However, in this case, the difference between the peak value of the engine torque and the ISC-required torque widens due to the execution of the startup noise amplification process (time t6), and there is a risk of a false determination that an abnormality has occurred in the engine 10. Therefore, the reference value used for abnormality determination during the execution of the startup noise amplification process is set to the engine torque during the execution of the startup noise amplification process when the engine 10 is functioning normally. This prevents the above-mentioned false determination. The reference value is set to a value corresponding to the engine speed by referring to a map corresponding to the engine speed during the execution of the startup noise amplification process when the engine 10 is functioning normally.

[0032] In the above embodiment, an ECU 20 mounted on an engine vehicle was described as an example of a vehicle control device. However, the vehicle on which such an ECU is mounted may be a hybrid vehicle equipped with both an engine and a motor as a power source for driving. In the case of an electric vehicle equipped only with a motor as a power source for driving, as a process to amplify the starting sound, a sound simulating the engine starting sound may be output from, for example, a speaker mounted in the passenger compartment when the motor starts up. This also improves the performance in circuit mode.

[0033] Although embodiments of the present invention have been described in detail above, the present invention is not limited to these specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims. [Explanation of Symbols]

[0034] 1 vehicle 10 Engines 20. ECU (Vehicle control unit, mode determination unit, starting sound control unit, fuel cut-off control unit, abnormality determination unit)

Claims

1. A mode determination unit that determines whether the vehicle's driving mode has been switched to circuit mode, The system includes a starting sound control unit that, when the mode determination unit makes a positive determination, performs a starting sound amplification process to increase the starting sound of the vehicle's power source compared to when the mode determination unit makes a negative determination. The aforementioned power source for driving is an engine. If the mode determination unit makes a positive determination, the starting sound control unit performs the starting sound amplification process by increasing the engine speed during startup compared to when the mode determination unit makes a negative determination. The system includes a fuel cut control unit that performs a fuel cut process for the engine when the engine speed during idle operation is higher than or equal to a fuel cut speed that is higher than the target idle speed. During the execution of the aforementioned starting sound amplification process, the fuel cut control unit sets the fuel cut rotation speed to a higher value than when the starting sound amplification process is stopped. The system includes an abnormality determination unit that determines that an abnormality has occurred in the engine if the engine torque becomes higher than a predetermined standard value or more during the execution of the aforementioned starting noise amplification process. The aforementioned reference value is set to the torque of the engine during the execution of the starting sound amplification process when the engine is functioning normally. The aforementioned starting sound control unit executes the starting sound amplification process when the conditions including the vehicle being stationary, the accelerator pedal being open at zero, and the shift range being in the N range are met. The aforementioned reference value is a value that fluctuates in accordance with the change in the torque of the engine during the execution of the starting sound amplification process when the engine is operating normally, and is set by referring to a map corresponding to the engine speed during the execution of the starting sound amplification process.

2. The vehicle control device according to claim 1, wherein the starting sound control unit stops the starting sound amplification process after a predetermined time has elapsed since the start of the starting sound amplification process.

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