Vehicle control device

Abstract

The present invention addresses the problem of providing a control device for a vehicle that improves performance in a racing track mode. The vehicle control device is provided with: a mode determination unit that determines whether or not the traveling mode of the vehicle is switched to a racing track mode; and a start-up sound control unit that, when the positive determination is made by the mode determination unit, executes a start-up sound increasing process that increases the start-up sound of a traveling power source of the vehicle compared to when the negative determination is made by the mode determination unit.

Description

Technical Field

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

[0002] There is a vehicle capable of switching a driving mode to a circuit mode (see, for example, Patent Document 1). Prior art literature Patent Literature

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-199382 Summary of the Invention Problems to be solved by the invention

[0004] It is expected that when the driving mode is switched to the track mode, different performances between the other modes and the track mode will be exhibited.

[0005] Therefore, an object of the present invention is to provide a vehicle control device with improved performance in track mode. Means for solving problems

[0006] The above-mentioned object is achieved by the following vehicle control device including a mode determination unit and a start-up sound control unit, wherein the mode determination unit determines whether the vehicle's driving mode is switched to the track mode, and the start-up sound control unit, when the mode determination unit makes an affirmative determination, performs a start-up sound increasing process to increase the start-up sound of the vehicle's driving power source compared to the case where the mode determination unit makes a negative determination.

[0007] The driving power source may be an engine, and when a positive determination is made in the mode determination unit, the start-up sound control unit performs the start-up sound amplification processing by increasing the burst speed when the engine is started compared to a case where a negative determination is made in the mode determination unit.

[0008] It may also be provided with a fuel cut-off control unit, which executes a fuel cut-off process for the engine when the speed of the engine in the idling state is higher than a fuel cut-off speed that is higher than a target idle speed. During the execution of the start-up sound amplification process, the fuel cut-off control unit sets the fuel cut-off speed to a higher value than when the start-up sound amplification process is stopped.

[0009] It may also be provided with an abnormality determination unit, which determines that an abnormality has occurred in the engine when the torque of the engine is higher than a specified reference value during the execution of the startup sound amplification process, and the reference value is set to the torque of the engine during the execution of the startup sound amplification process when the engine is normal.

[0010] The startup sound control unit may stop the startup sound amplification process after a predetermined time has passed since the startup sound amplification process was started. Effects of the Invention

[0011] According to the present invention, a vehicle control device having improved performance in track mode can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the vehicle. Figure 2 is a flowchart illustrating performance control. Figure 3 is a time chart illustrating performance control. DETAILED DESCRIPTION

[0013] [Schematic structure of the vehicle] Figure 1 This is a schematic diagram showing the schematic structure of the vehicle 1. The vehicle 1 includes 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 may also be a diesel engine. The engine 10 is started by the starter 9. The crankshaft 11 of the engine 10 is connected to the torque converter 12. The turbine shaft 13 of the torque converter 12 is connected to the input side of the automatic transmission 14, transmitting the driving force of the engine 10 to the automatic transmission 14. The output shaft 15 of the automatic transmission 14 is connected to the differential gear 16 serving as the final drive reducer. The differential gear 16 is connected to the left and right axles 17. The driving force transmitted to the output shaft 15 is transmitted to the drive wheels 18 via the axle 17.

[0014] The automatic transmission 14 is a stepped transmission that includes multiple hydraulic friction elements and a planetary gear mechanism. The multiple friction elements are selectively engaged in the automatic transmission 14 to shift the vehicle into one of the P (Park) range, R (Reverse) range, N (Neutral) range, and D (Drive) range.

[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. Specifically, it functionally implements the mode determination unit, starting sound control unit, fuel cutoff control unit, and abnormality determination unit, which will be described later.

[0016] The ECU 20 is connected to a crank angle sensor 21, a gear position sensor 22, an air flow meter 23, an accelerator position sensor 24, a mode switch 25, and a vehicle speed sensor 26. The crank angle sensor 21 detects the engine speed. The gear position sensor 22 detects the position of the gear shift lever. The air flow meter 23 detects the amount of air intake into the engine 10. The accelerator position sensor 24 detects the accelerator pedal position (i.e., the accelerator position). The mode switch 25 switches between driving modes (described later). The vehicle speed sensor 26 detects vehicle speed.

[0017] The ECU 20 calculates the requested torque and target speed for the engine 10 based on the engine speed, intake air volume, and accelerator position detected by the aforementioned sensors. The ECU 20 controls the fuel injection amount, intake air volume, and ignition timing in accordance with the requested torque and target 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 reaches the target idle speed and the engine torque reaches the supplied torque.

[0018] The ECU 20 can switch the driving mode between normal mode, sport mode, eco mode, and track mode. The driver can operate the mode switch 25 to switch the driving mode between normal mode, sport mode, or eco mode. For track mode, for example, the driver can switch the driving mode to track mode by operating a mobile device such as a smartphone while the vehicle 1 is at a racetrack. When the driving mode is switched to track mode, the control map of the vehicle 1 is switched to a control map corresponding to track mode that prioritizes driving performance. This improves the driving performance of the vehicle 1 compared to driving modes other than track mode. Of course, switching to track mode can also be performed using the mode switch 25 as described above.

[0019] The ECU 20 executes a fuel cutoff process, which stops fuel injection into the engine 10 when predetermined conditions are met. Specifically, the ECU 20 executes a fuel cutoff process for the engine 10 when the engine speed exceeds the fuel cutoff speed. The fuel cutoff speed is set to a value higher than the target idle speed. This improves fuel economy. Fuel cutoff is also executed during idling. The fuel cutoff process is an example of a process executed by the fuel cutoff control unit.

[0020] [Performance Control] Figure 2is a flowchart illustrating performance control. This control is continuously repeated while the ignition is on. ECU 20 determines whether the driving mode has been switched to track mode (step S1). If the answer is no in step S1, this control ends. Step S1 is an example of processing performed by the mode determination unit. If the answer is yes in step S1, ECU 20 determines whether there is a request to start the engine 10 (step S2). If the answer is no in step S2, this control ends.

[0021] If the answer is yes in step S2, a determination is made as to whether the prerequisites for executing the startup sound amplification process, described later, are met (step S3). Preconditions include, for example, the vehicle being parked, the accelerator opening being 0 (zero), and the shift range being the N range. In the startup sound amplification process, detailed later, the burst speed of engine 10 is increased during startup. If the aforementioned prerequisites are met, safety is ensured by executing the startup sound amplification process. If the answer is no in step S3, this control ends.

[0022] If the answer is yes in step S3, the ECU 20 executes the start-up process of the engine 10 (step S4) and the start-up sound increase process (step S5). The start-up process is a process of starting the engine 10 by the starter 9 and starting fuel injection when the engine speed becomes above a specified value. The start-up sound increase process is a process of making the start-up sound of the engine 10 louder than when the driving mode is other than the track mode. Specifically, the start-up sound is increased by increasing the burst speed when the engine 10 is started. The burst speed refers to the engine speed that rises to a speed higher than the target idle speed just after the engine 10 is started. The increase in the burst speed is achieved by increasing the throttle opening at the time of startup and increasing the fuel injection amount compared to when the driving mode is other than the track mode. In this way, since the start-up sound of the engine 10 is loud, the performance of the track mode is improved. Step S5 is an example of the process performed by the start-up sound control unit.

[0023] Next, while the startup sound amplification process is being executed, the ECU 20 sets the aforementioned fuel cutoff speed to a higher value than when the startup sound amplification process is stopped (step S6). During the execution of the startup sound amplification process, the burst speed increases as described above. Since the fuel cutoff speed is set to a higher value during the execution of the startup sound amplification process, the fuel cutoff process is prevented from being executed due to the burst speed exceeding the fuel cutoff speed during the execution of the startup sound amplification process. Step S6 is an example of the process executed by the fuel cutoff control unit.

[0024] Next, the ECU 20 determines whether the engine torque is greater than a predetermined reference value by a predetermined value or more (step S7). The reference value is set to the engine torque during the start-up sound amplification process when the engine 10 is operating normally. The reference value is previously obtained through experiments and stored in the ROM of the ECU 20. Furthermore, the engine torque can be calculated based on the intake air volume detected by the air flow meter 23, or detected by a torque sensor. Step S7 is an example of the process performed by the abnormality determination unit.

[0025] If the answer is NO in step S7, the ECU 20 then determines whether a predetermined time has passed since the start-up sound amplification process was started (step S8). If the answer is NO in step S8, the steps from step S5 onwards are executed again.

[0026] If the answer is yes in step S8, the ECU 20 terminates the startup sound amplification process (step S9). As described above, the startup sound amplification process increases the engine 10's burst speed during startup. Therefore, for safety reasons, the startup sound amplification process is terminated. Furthermore, upon termination of the startup sound amplification process, the fuel cutoff speed and reference value described above are restored to their initial, lower values.

[0027] If the answer is yes in step S7, the ECU 20 determines that an abnormality has occurred in the engine 10 (step S10) and executes a process to ensure safety (step S11). Examples of the process to ensure safety include stopping the start sound amplification process, limiting the vehicle speed, and forcibly stopping the engine 10. Step S10 is an example of the process executed by the abnormality determination unit.

[0028] Figure 3 is a time chart illustrating performance control. Figure 3 The starter drive state, engine speed, ON / OFF state of the start sound increase processing flag, throttle opening, and engine torque change are shown. Figure 3 ] shows a reference value for determining an abnormality of the engine 10 during the execution of the above-mentioned startup sound amplification process. Figure 3 The ISC requested torque is the engine torque required for the engine speed to converge to the target idle speed.

[0029] If a request to start engine 10 is received during Track Mode, starter 9 is driven (time t1), and engine speed begins to increase (time t2). The starter sound increase flag is then turned on, the throttle opening is increased by a predetermined amount, combustion begins, and torque increases (time t3). Starter 9 is then stopped (time t4), and engine torque begins to increase further (time t5).

[0030] If the engine speed becomes higher than the specified end judgment speed, the start sound increase processing flag is switched to OFF, the throttle opening is reduced to the initial opening, and the torque is reduced (time t6). In addition, the fuel cut-off speed during the execution of the start sound increase processing is set to a value higher than the end judgment speed. Then, the engine torque converges to the ISC requested torque, and the engine speed converges to the target idle speed. In this way, the start sound increase processing stops after the specified time as described above. That is, in this embodiment, when the engine speed becomes higher than the specified end judgment speed, it is deemed that a specified time has passed since the start of the start sound increase processing, and the start sound increase processing stops. In addition, the time from when the start sound increase processing flag is switched to ON can also be measured, and the start sound increase processing can be stopped when the measured time has passed the specified time.

[0031] like Figure 3 As shown, during the execution of the start sound amplification process, the reference value fluctuates along the transition of the engine torque during normal operation. For example, it can also be considered that during the execution of the start sound amplification process, when the engine torque is higher than the ISC request torque by more than a specified value, it is determined that an abnormality has occurred in the engine 10. However, in this case, due to the execution of the start sound amplification process, the difference between the peak value of the engine torque and the ISC request torque increases (at time t6), which may lead to an erroneous determination that an abnormality has occurred in the engine 10. Therefore, the reference value used for the abnormality determination during the execution of the start sound amplification process is set to the engine torque during the execution of the start sound amplification process when the engine 10 is normal. Therefore, the above-mentioned erroneous determination is avoided. In addition, with reference to the corresponding figure of the engine speed during the execution of the start sound amplification process when the engine 10 is normal, the reference value is set to a value corresponding to the engine speed.

[0032] While the above embodiment describes the ECU 20 installed in an engine vehicle as an example of a vehicle control device, the vehicle equipped with such an ECU may also be a hybrid vehicle equipped with an engine and an electric motor as driving power sources. Furthermore, in the case of an electric vehicle equipped with only an electric motor as a driving power source, a sound simulating the engine startup sound can be output from, for example, a speaker installed in the vehicle cabin when the motor starts, as a starting sound amplification process. This also enhances performance in track mode.

[0033] While the embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention as described in the claims. Description of the label

[0034] 1 vehicle 10 Engine 20 ECU (vehicle control device, mode determination unit, start sound control unit, fuel cut control unit, abnormality determination unit).

Claims

1. A vehicle control device comprising: a mode determination unit, determining whether the vehicle's driving mode is switched to a track mode; and The startup sound control unit, when the mode determination unit makes an affirmative determination, executes startup sound amplification processing for increasing the startup sound of the driving power source of the vehicle compared to when the mode determination unit makes a negative determination.

2. The vehicle control device according to claim 1, wherein: The driving power source is an engine, When the mode determination unit makes an affirmative determination, the startup sound control unit executes the startup sound increasing process by increasing the burst rotation speed at the time of engine startup compared to when the mode determination unit makes a negative determination.

3. The vehicle control device according to claim 2, wherein: A fuel cutoff control unit is provided for executing a fuel cutoff process for the engine when the engine speed in an idling state is equal to or higher than a fuel cutoff speed that is higher than a target idle speed. During execution of the startup sound amplification process, the fuel cut control unit sets the fuel cut rotation speed to a higher value than during suspension of the startup sound amplification process.

4. The vehicle control device according to claim 3, wherein: An abnormality determination unit is provided for determining that an abnormality has occurred in the engine when the torque of the engine exceeds a predetermined reference value by a predetermined value or more during the execution of the startup sound increasing process. The reference value is set to the torque of the engine during execution of the startup sound increasing process when the engine is normal.

5. The vehicle control device according to any one of claims 2 to 4, wherein: The startup sound control unit stops the startup sound amplification process after a predetermined time has passed since the startup sound amplification process was started.

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