Vehicle control system

Abstract

To provide a vehicle control device that can suppress delays in gear changes. [Solution] The vehicle control device of the present invention is provided in a vehicle having an engine, an automatic transmission that changes the speed of rotation output from the engine and transmits it to the drive wheels, and an accelerator operating member operated by the driver according to the requested output, and is capable of performing blipping down control which temporarily increases the engine torque when the accelerator operating member is returned and the automatic transmission performs a downshift, and when predetermined conditions are met, the device determines the engine's driving state or the engine's driven state based on the destination engine torque, and performs the blipping down control when downshifting in the driven state.

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a vehicle control device capable of executing blipping control that temporarily increases engine torque when performing a downshift.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0004] If actual engine torque remains at the time of a shift instruction, the shift starts from a downshift because the engine is in a driving state at the start of the shift, and transition to blipping down control is not possible even when the engine enters a driven state, resulting in prolonged shift duration.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a vehicle control device that can suppress prolonged shift duration.

Means for Solving the Problems

[0006] To solve the above-mentioned problems and achieve the objective, the vehicle control device according to the present invention is provided for a vehicle having an engine, an automatic transmission that changes the speed of rotation output from the engine and transmits it to the drive wheels, and an accelerator operating member operated by the driver in accordance with the requested output, and is capable of performing blipping down control to temporarily increase engine torque when the accelerator operating member is returned and the automatic transmission performs a downshift, and is characterized in that, when predetermined conditions are met, the driving state of the engine or the driven state of the engine is determined based on the destination engine torque, and the blipping down control is performed when downshifting in the driven state.

[0007] As a result, the vehicle control device according to the present invention can suppress the delay in gear changes by determining the driven state using the destination engine torque and performing blipping down control even when actual engine torque remains.

[0008] Furthermore, in the above, the predetermined conditions may be that the actual engine torque for each deceleration is less than or equal to a predetermined value, and the deceleration has not decreased beyond a predetermined value, or the actual engine torque has not increased beyond a predetermined value.

[0009] This makes it possible to suppress the deterioration of shift quality due to a sudden jolt or engine revving when blipping down control is performed. [Effects of the Invention]

[0010] The vehicle control device according to the present invention determines the driven state using the destination engine torque, and since it performs blipping down control even when actual engine torque remains, it has the effect of suppressing delays in gear changes. [Brief explanation of the drawing]

[0011] [Figure 1]Figure 1 is a diagram showing the schematic configuration of a vehicle according to this embodiment. [Figure 2] Figure 2 is a timing chart showing an example of blipping down control performed by the electronic control unit in a vehicle according to this embodiment. [Figure 3] Figure 3 is a flowchart showing an example of blipping-down control performed by an electronic control unit in a vehicle according to this embodiment. [Modes for carrying out the invention]

[0012] The following describes an embodiment of the vehicle control device according to the present invention. However, the present invention is not limited to this embodiment.

[0013] Figure 1 is a diagram showing the schematic configuration of a vehicle 10 according to an embodiment.

[0014] As shown in Figure 1, the vehicle 10 according to this embodiment is equipped with an engine 12 as a driving force source. The output of the engine 12 is transmitted from the automatic transmission 14 to the left and right drive wheels 18 via a differential gear 16. A power transmission device such as a damper device or a torque converter is provided between the engine 12 and the automatic transmission 14.

[0015] The engine 12 is equipped with various engine control devices 30 necessary for controlling the output of the engine 12, such as an electronic throttle valve and a fuel injection system. The electronic throttle valve controls the amount of intake air. The fuel injection system controls the amount of fuel supplied. The automatic transmission 14 is a stepped transmission that can achieve multiple forward gear stages with different gear ratios by changing the engagement and disengagement states of multiple hydraulic friction engagement devices (such as clutches and brakes). The automatic transmission 14 performs gear shifting control by switching the engagement and disengagement states of multiple hydraulic friction engagement devices using electromagnetic hydraulic control valves and switching valves provided in the hydraulic control device 32.

[0016] The vehicle 10 according to this embodiment is equipped with an electronic control unit 40 as a controller for controlling the output of the engine 12 via the engine control device 30 and for performing gear shift control to switch the forward gears of the automatic transmission 14 via the hydraulic control device 32. The electronic control unit 40 is composed of a so-called microcomputer having a CPU, ROM, RAM, and input / output interfaces, and performs signal processing according to a program pre-stored in ROM while utilizing the temporary storage function of RAM. The electronic control unit 40 is supplied with a signal from the accelerator operation amount sensor 50 that represents the accelerator operation amount (accelerator opening), which is the amount of depression of the accelerator pedal 52. The accelerator operation amount corresponds to the requested output. The accelerator pedal 52 is an accelerator operating member operated by the driver in response to the requested output. The electronic control unit 40 is also supplied with a signal from the brake operation amount sensor 54 that represents the brake operating force, which is the amount of depression of the brake pedal 56. The brake pedal 56 is a brake operating member operated by the driver in response to the requested braking force.

[0017] Furthermore, the electronic control unit 40 is supplied with a signal from the engine speed sensor 58 representing the rotational speed of the engine 12 (engine rotational speed). The electronic control unit 40 is also supplied with a signal from the input speed sensor 60 representing the input rotational speed of the automatic transmission 14. Furthermore, the electronic control unit 40 is supplied with a signal from the output speed sensor 62 representing the output rotational speed of the automatic transmission 14. The output rotational speed corresponds to the vehicle speed. In addition, the electronic control unit 40 is supplied with signals from the vehicle weight sensor 64 and the road gradient sensor 66 representing the vehicle weight and road gradient, respectively.

[0018] The electronic control device 40 includes an engine control unit 42, a shift control unit 44, and a driving force source brake control unit 46. The engine control unit 42 basically controls the electronic throttle valve, the fuel injection device, and the like of the engine control device 30 so as to increase or decrease the output of the engine 12 in accordance with the accelerator operation amount. Further, even while the vehicle is traveling, a fuel cut for stopping fuel supply by the fuel injection device is performed at the time of accelerator OFF where the accelerator operation amount (accelerator opening degree) is 0. The shift control unit 44 basically controls the hydraulic control device 32 so as to switch the forward gear stage of the automatic transmission 14 in accordance with a predefined shift condition. The shift condition is, for example, a shift map defined using vehicle speed, accelerator operation amount, and the like as parameters, and is defined such that as the vehicle speed increases, the gear stage is switched to a high-speed gear stage with a smaller gear ratio, and as the accelerator operation amount increases, the gear stage is switched to a low-speed gear stage with a larger gear ratio.

[0019] The driving force source brake control unit 46, for example, when the accelerator pedal 52 is operated to return, downshifts the automatic transmission 14 as necessary to increase the engine rotation speed, and applies a braking force (engine brake) by the pumping loss or the like of the engine 12.

[0020] FIG. 2 is a timing chart showing an example of blipping down control performed by the electronic control device 40 in the vehicle 10 according to the embodiment.

[0021] As shown in FIG. 2, when a predetermined condition is satisfied, the electronic control device 40 determines the driving / driven state of the engine 12 (the driving state of the engine 12 or the driven state of the engine 12) based on the destination engine torque (look-ahead engine torque), and performs blipping down control at the time of downshifting while the engine 12 is in the driven state. The predetermined condition is, for example, a case where the deceleration is equal to or greater than a predetermined value, and / or the engine torque increase amount is less than a predetermined value, and / or the actual engine torque for each deceleration is equal to or less than a predetermined value.

[0022] Note that in a driven state of the engine 12, the rotation (power) output from the engine 12 is transmitted to the drive wheels 18. Further, in a driven state of the engine 12, the rotation transmitted from the drive wheels 18 during coasting of the vehicle 10 or the like is transmitted to the engine 12, whereby engine braking can be generated.

[0023] Here, as shown in FIG. 2, examples of the downshift executed during decelerated travel accompanying accelerator OFF include a downshift requested by operation of a shift lever when the accelerator is OFF, and a downshift executed accompanying brake ON when the accelerator is OFF. Then, when executing such a downshift, the electronic control unit 40 is capable of executing blipping down control for performing a so-called blipping downshift in which the shift is rapidly advanced by performing engine torque increase that raises the engine torque during the shift transition process.

[0024] FIG. 3 is a flowchart illustrating an example of the blipping down control executed by the electronic control unit 40 in the vehicle 10 according to the embodiment.

[0025] First, the electronic control unit 40 determines whether or not it is a downshift instruction due to idle ON and sudden braking (step S1). When determining that it is not a downshift instruction due to idle ON and sudden braking (No in step S1), the electronic control unit 40 proceeds to step S5, and determines the driven / non-driven state of the engine 12 based on the actual engine torque.

[0026] On the other hand, when the electronic control unit 40 determines that it is a downshift instruction due to idle ON and sudden braking (Yes in step S1), the process proceeds to step S2.

[0027] In step S2, the electronic control unit 40 determines whether or not the actual engine torque for each deceleration is equal to or less than a predetermined value (step S2). When determining that the actual engine torque for each deceleration is not equal to or less than the predetermined value (No in step S2), the electronic control unit 40 proceeds to step S5, and determines the driven / non-driven state of the engine 12 based on the actual engine torque.

[0028] If blipping down control is performed when the actual engine torque for each deceleration exceeds a predetermined value, the shift quality of the blipping down control will deteriorate due to a sudden lurching sensation. Therefore, if it is determined that the actual engine torque for each deceleration is not below a predetermined value, the driving / driving of engine 12 is determined using the actual engine torque as before.

[0029] On the other hand, if the electronic control unit 40 determines that the actual engine torque for each deceleration is below a predetermined value (Yes in step S2), it proceeds to step S3.

[0030] In step S3, the electronic control unit 40 determines whether the deceleration has not decreased below a predetermined value, or whether the actual engine torque has increased above a predetermined value (step S3). If the electronic control unit 40 determines that either the deceleration has decreased above a predetermined value or the actual engine torque has increased above a predetermined value (No in step S3), it proceeds to step S5 to determine whether the engine 12 is driven or driven based on the actual engine torque.

[0031] Here, if the deceleration decreases (falls below a predetermined value), the shift quality deteriorates due to a sudden lurching sensation, similar to when the actual engine torque for each deceleration exceeds a predetermined value. Therefore, when the electronic control unit 40 determines that the deceleration has fallen below a predetermined value, it determines whether the engine 12 is driven or driven using the conventional actual engine torque and switches between a driven downshift and a driven downshift. In this embodiment, "driven downshift" refers to a downshift when the engine 12 is in a driven state. In this embodiment, "driven downshift" refers to a downshift when the engine 12 is driven.

[0032] Furthermore, if the actual engine torque increases due to the accelerator being pressed, etc., and the blipping down control is continued, engine blow-out may occur. Therefore, when the electronic control unit 40 determines that the actual engine torque has risen above a predetermined value, it determines whether the engine 12 is driven or driven based on the actual engine torque and switches between the drive down and driven down gear modes.

[0033] On the other hand, if the electronic control unit 40 determines that the deceleration has not decreased below a predetermined value, or that the actual engine torque has not increased above a predetermined value (Yes in step S3), it proceeds to step S4.

[0034] In step S4, the electronic control unit 40 determines whether the engine 12 is driven or driven based on the destination engine torque, and performs (starts) blipping down control when the engine 12 is driven and downshifting (for example, when downshifting from 3rd (third gear) to 2nd (second gear) in the output gear stages shown in Figure 2). After that, the electronic control unit 40 proceeds to step S6.

[0035] Here, when the conditions of steps S2 and S3 are met, the electronic control unit 40 determines whether the engine 12 is driven or driven based on the destination engine torque, and blipping down control is adopted, thereby improving the opportunity to output blipping down control while maintaining high shift quality.

[0036] In step S5, the electronic control unit 40 determines whether the engine 12 is driven or driven based on the actual engine torque, and switches between drive-down and drive-down gears. After that, the electronic control unit 40 proceeds to step S6.

[0037] In step S6, the electronic control unit 40 determines whether or not the gear shift has been completed (step S6). If the electronic control unit 40 determines that the gear shift has not been completed (No in step S6), it proceeds to step S3.

[0038] On the other hand, if the electronic control unit 40 determines that the gear shift is complete (Yes in step S6), it terminates the control for that example.

[0039] As described above, in a sudden braking downshift immediately after releasing the accelerator, the electronic control unit 40 uses the destination engine torque to determine whether the engine 12 is driven or driven, even if there is still actual engine torque remaining at the time of the shift command. As a result, the electronic control unit 40 can determine that the engine 12 is driven from the start of the shift (start of the downshift) and perform blipping down control, thereby suppressing delays in shifting.

[0040] Furthermore, in the vehicle 10 according to this embodiment, the blipping down control is activated by the electronic control device 40 even when actual engine torque remains, resulting in a shorter shift time and making hesitation less likely during re-acceleration.

[0041] Furthermore, in the vehicle 10 according to this embodiment, the electronic control device 40 has the conditions for the actual engine torque for each deceleration calculated from the brake pedal force as the operating conditions for blipping down control, thereby improving the opportunities for outputting blipping down control while maintaining high shift quality. [Explanation of symbols]

[0042] 10 vehicles 12 Engines 14 Automatic transmission 16 Differential gear 18 drive wheels 30 Engine control equipment 32 Hydraulic control device 40 Electronic control unit 42 Engine Control Unit 44. Gear shift control unit 46. ​​Drive force source brake control unit 50 Accelerator pedal input sensor 52 Accelerator pedal 54 Brake operation amount sensor 56 Brake pedal 58 Engine speed sensor 60 Input rotational speed sensor 62 Output rotational speed sensor 64 Vehicle weight sensor 66 Road surface gradient sensor

Claims

1. The engine and An automatic transmission that changes the speed of the rotation output from the engine and transmits it to the drive wheels, An accelerator operating member operated by the driver in response to the requested output, Vehicles equipped with, When the accelerator operating member is returned to its original position and the automatic transmission performs a downshift, a blipping down control can be implemented to temporarily increase engine torque. A vehicle control device, When predetermined conditions are met, the engine's driving state or under-driven state is determined based on the destination engine torque, and the blipping down control is performed during a downshift in the under-driven state. A vehicle control device characterized by the following features.

2. The aforementioned predetermined conditions are: When the actual engine torque for each deceleration is below a predetermined value, This is the case when the deceleration does not decrease to a predetermined value or when the actual engine torque does not increase to a predetermined value. The vehicle control device according to feature 1.

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