Vehicle

Abstract

To execute vehicle control during stoppage with improved appropriateness such as adjusting a vehicle height and applying vibration to a vehicle while the same is stationary.SOLUTION: A vehicle comprises: a drive device which is capable of applying drive force to some of all wheel or each wheel; a brake device which is capable of applying brake force to each wheel; and a control device which executes control during stoppage such as adjusting a vehicle height and applying vibration to the vehicle while the same is stationary. The control device executes the control during stoppage after confirming that all wheels will not undergo slippage when controlling the drive device and the brake device so that gradually intensifying drive force is applied to at least some of the wheels to which the drive force is applied until the drive force reaches predetermined drive force and sufficient brake force is applied to the other wheels while executing the control during stoppage such as adjusting the vehicle height and applying vibration to the vehicle.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle, and more particularly to a vehicle equipped with a drive device capable of applying a driving force to wheels and a braking device capable of applying a braking force to wheels. [Background technology]

[0002] Conventionally, a vehicle height adjustment device of this type has been proposed in which the vehicle height is adjusted by applying a drive torque difference between the front and rear wheels (see, for example, Patent Document 1). This vehicle is equipped with torque control means that can independently control the drive torque of the front and rear wheels, and adjusts the vehicle height by applying a drive torque difference between the front and rear wheels. This results in a vehicle height adjustment device that is space-efficient. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-069395 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned vehicle, depending on the condition of the ground on which it is parked, if the front or rear wheels do not have sufficient grip, slippage will occur at one or both of the front and rear wheels, and the vehicle height cannot be adjusted.

[0005] The main purpose of the automobile of the present disclosure is to more appropriately execute stopping control that changes the vehicle height and applies vibration to the vehicle while the vehicle is stopped. [Means for solving the problem]

[0006] The automobile of the present disclosure employs the following measures to achieve the above-mentioned main object.

[0007] The vehicle of the present disclosure comprises: A drive device capable of applying drive force to some or all of the wheels; a braking device capable of applying braking force to each of the wheels; a control device that executes vehicle-stop control to control the drive device and the braking device so as to change the vehicle height or apply vibration to the vehicle while the vehicle is stopped; A motor vehicle comprising: the control device, when executing the vehicle-stop control, applies a driving force that gradually increases until a predetermined driving force is reached to at least some of the wheels to which the driving force is applied in the vehicle-stop control, and controls the drive device and the brake device so as to apply a sufficient braking force to the remaining wheels, and then executes the vehicle-stop control after confirming that no slip occurs in any of the wheels. It is characterized by:

[0008] In the automobile of the present disclosure, when executing stopping control to change the vehicle height or impart vibration to the vehicle while the vehicle is stopped, the stopping control is executed after confirming that no slip occurs on any of the wheels when the driving device and the braking device are controlled so that a driving force that gradually increases until a predetermined driving force is imparted to at least some of the wheels to which driving force is imparted in the stopping control and sufficient braking force is imparted to the remaining wheels. This makes it possible to avoid a situation in which the vehicle height cannot be adjusted or vibration cannot be imparted properly due to slippage occurring when the stopping control is executed, and as a result, the stopping control to change the vehicle height or impart vibration to the vehicle while the vehicle is stopped can be executed more properly. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram showing an outline of the configuration of an automobile 20 according to an embodiment of the present disclosure. [Figure 2] 4 is a flowchart showing an example of a vehicle stop control execution permission / denial process executed by the main ECU 40. DETAILED DESCRIPTION OF THE INVENTION

[0010] Next, a mode (embodiment) for carrying out the present disclosure will be described. Fig. 1 is a configuration diagram showing an outline of the configuration of an automobile 20 as one embodiment of the present disclosure. The automobile 20 of the embodiment includes a front-wheel drive device 30f, a rear-wheel drive device 30r, a brake device 34, and a main electronic control unit (hereinafter referred to as "main ECU") 40.

[0011] The front-wheel drive device 30f includes a front-wheel motor configured as a synchronous generator motor, an inverter that drives the front-wheel motor, and receives power from a battery (not shown). The front-wheel drive device 30f is connected to a front-wheel drive shaft 22f that is connected to the front wheels 26a, 26b via a differential gear 24f. The front-wheel drive device 30f is drive-controlled by a drive electronic control unit (hereinafter referred to as "drive ECU") 32.

[0012] Like the front-wheel drive device 30f, the rear-wheel drive device 30r includes a rear-wheel motor configured as a synchronous generator-motor, an inverter that drives the rear-wheel motor, and receives power from a battery (not shown). The rear-wheel drive device 30r is connected to a rear-wheel drive shaft 22r that is connected to rear wheels 27a, 27b via a differential gear 24r. Like the front-wheel drive device 30f, the rear-wheel drive device 30r is drive-controlled by a drive ECU 32. The drive ECU 32 communicates with the main ECU 40.

[0013] The brake device 34 is configured as a well-known hydraulically driven brake device, and is configured to be able to apply braking force resulting from the brake depression force applied by depressing the brake pedal 57 and braking force resulting from hydraulic pressure adjustment to the front wheels 26a, 26b and the rear wheels 27a, 27b. The brake device 34 is driven and controlled by a brake electronic control unit (hereinafter referred to as "brake ECU") 36. The brake ECU 36 is configured by a microcomputer centered around a CPU (not shown). The brake ECU 36 controls the braking force resulting from the brake depression force applied by the brake device 34 and braking force resulting from hydraulic pressure adjustment. The brake ECU 36 communicates with the main ECU 30.

[0014] The main ECU 40 is configured as a microcomputer having a CPU 41, ROM 42, RAM 43, flash memory 44, and input / output and communication ports (not shown). Signals from various sensors are input to the main ECU 40 via the input ports. Examples of signals input to the main ECU 40 include an ignition signal from an ignition switch 51, a vehicle speed V from a vehicle speed sensor 52, wheel speeds Vwfr, Vwfl, Vwrr, and Vwrl from wheel speed sensors 53, and an acceleration α from an acceleration sensor 54. Other signals input to the main ECU 40 include an accelerator opening Acc from an accelerator pedal position sensor 56 that detects the amount of depression of an accelerator pedal 55, a brake pedal position BP from a brake pedal position sensor 58 that detects the amount of depression of a brake pedal 57, and a switch signal from a vehicle-stop control request switch 63. Vehicle-stop control will be described later.

[0015] The main ECU 40 also receives a shift position signal SP from a shift position sensor 62, which detects the operating position of a shift lever 61 input to the shift ECU 60, through communication with a shift electronic control unit (hereinafter referred to as "shift ECU") 60. The shift ECU 60 is configured by a microcomputer centered around a CPU (not shown). Shift positions include a parking position (P range), a neutral position (N range), a drive position (D range), a reverse position (R range), a brake position (B range), and a sequential shift position (S range).

[0016] Various control signals are output from the main ECU 30 via an output port. Examples of control signals output from the main ECU 30 include a display control signal to the display device 70 and a communication control signal to the communication device 72. The main ECU 30 also communicates with a navigation device 80.

[0017] The navigation device 80 includes a main body 82 with a built-in control unit, a GPS antenna 84 that receives information about the current location of the vehicle, and a display 86. The control unit of the main body 82 has a storage medium (e.g., a hard disk or SSD) that stores map information and the like, an input / output port, and a communication port. The map information stores service information (e.g., tourist information, parking lots, etc.) and road information for each driving section (e.g., between traffic lights and between intersections) as a database. The road information includes distance information, road width information, number of lanes information, area information (urban or suburban), type information (general road or expressway), gradient information, legal speed limit, number of traffic lights, turning radius of each curve, etc. The display 86 displays various information such as information about the current location of the vehicle and the planned route to the destination, and is configured as a touch panel display that allows the user to input various instructions. When a destination is set by a user operating the display 86, the main body 62 of the navigation device 80 sets a planned driving route from the current location of the vehicle to the destination based on map information stored in the main body 82 and the current location and destination of the vehicle obtained from the GPS antenna 84, and displays the set planned driving route on the display 86 to provide route guidance.

[0018] In the embodiment, while the automobile 20 is parked with the shift lever 61 in the parking position, the front wheel drive unit 30f and the rear wheel drive unit 30r are controlled to rotate the front wheels 26a, 26b backward and the rear wheels 27a, 27b forward, thereby increasing the vehicle height, or conversely, the front wheel drive unit 30f and the rear wheel drive unit 30r are controlled to rotate the front wheels 26a, 26b forward and the rear wheels 27a, 27b backward, thereby decreasing the vehicle height. Furthermore, while the automobile 20 of the embodiment is parked with the shift lever 61 in the parking position, the vehicle 20 performs vehicle vibration control while parked, such as by rotating the front wheels 26a, 26b forward or backward while applying braking force to the rear wheels 27a, 27b to vibrate the vehicle, or by rotating the rear wheels 27a, 27b forward or backward while applying braking force to the front wheels 26a, 26b to vibrate the vehicle, or by rotating the front wheels 26a, 26b forward or backward and the rear wheels 27a, 27b forward or backward to vibrate the vehicle. In this embodiment, such vehicle height control while parked and vehicle vibration control while parked are collectively referred to as vehicle feel control.

[0019] Next, the operation of the automobile 20 of this embodiment, particularly the operation when determining whether or not to permit execution of the vehicle stop control while parked, will be described. Figure 2 is a flowchart showing an example of a vehicle stop control execution permission / prohibition process executed by the main ECU 40.

[0020] When the vehicle stop control execution permission / denial process is executed, the main ECU 40 first determines whether or not there is a request for vehicle stop control (step S100). This request can be determined by whether or not the vehicle stop control request switch 63 is turned on while the vehicle is stopped with the shift lever 61 in the parking position. If it is determined that there is no request for vehicle stop control, the main ECU 40 determines that this process is unnecessary and ends this process.

[0021] If it is determined in step S100 that a request for vehicle-stop control has been made, braking force is applied to wheels other than the target wheel to prevent rotation (step S110). In this state, the driving force Tm of the target wheel is increased by an amount of change ΔT at a time until it reaches a threshold value Tref, and it is determined whether any wheel has slipped (steps S120 to S150). The target wheel is either the front wheels 26a, 26b or the rear wheels 27a, 27b in the case of vehicle-stop height control, and either the drive-side wheel or the front wheels 26a, 26b or the rear wheels 27a, 27b in the case of vehicle-stop vibration control. The threshold value Tref is a value slightly larger than the driving force applied to the wheels that are driven during vehicle-stop control. Whether slip has occurred can be determined by whether the rotation angle of the target wheel is greater than the threshold value.

[0022] If it is determined in steps S120 to S140 that no slip occurs in any of the wheels until the driving force Tm of the target wheels reaches the threshold value Tref, it is determined that there is sufficient grip on the road surface to execute the vehicle stop control, and the application of the driving force Tm is canceled (step S160), the execution of the vehicle stop control is permitted (step S170), and this process ends. When the execution of the vehicle stop control is permitted, the main ECU 40 executes the vehicle stop control.

[0023] If it is determined in steps S120 to S140 that a wheel has slipped before the driving force Tm of the target wheel reaches the threshold value Tref, it is determined that the road surface does not have sufficient grip to execute the vehicle stop control, and immediately after determining that a slip has occurred, the application of the driving force Tm is stopped (step S180), the execution of the vehicle stop control is prohibited (step S190), and this process ends. If the execution of the vehicle stop control is prohibited, the main ECU 40 does not execute the vehicle stop control.

[0024] In the vehicle 20 described above, when the vehicle stop control is executed, braking force is applied to wheels other than the target wheel to prevent them from rotating, and in this state, the system determines whether any wheel has slipped while increasing the change amount ΔT by one step until the driving force Tm of the target wheel reaches the threshold value Tref. If no wheel slips until the driving force Tm of the target wheel reaches the threshold value Tref, the system permits execution of the vehicle stop control. However, if any wheel slips before the driving force Tm of the target wheel reaches the threshold value Tref, the system prohibits execution of the vehicle stop control. In other words, the system permits execution of the vehicle stop control when it is determined that there is sufficient grip on the road surface to execute the vehicle stop control. This allows the vehicle stop control, which changes the vehicle height and applies vibrations to the vehicle while the vehicle is stopped, to be executed more appropriately.

[0025] Although the automobile 20 of the embodiment is equipped with a front-wheel drive unit 30f that drives the front wheels 26a, 26b and a rear-wheel drive unit 30r that drives the rear wheels 27a, 27b, an in-wheel motor that drives each of the front wheels 26a, 26b and the rear wheels 27a, 27b individually may be provided. In this case, the vehicle stop control can include control for tilting the vehicle in a rolling direction or rolling it, such as rotating the front wheels 26a backward and the front wheels 26b forward, correspondingly rotating the rear wheels 27a forward and the rear wheels 27b backward, or conversely, rotating the front wheels 26a forward and the front wheels 26b backward, correspondingly rotating the rear wheels 27a backward and the rear wheels 27b forward, correspondingly.

[0026] The correspondence between the main elements of the embodiment and the main elements of the invention described in the Summary of the Invention section will be explained. The front wheel drive unit 30f and the rear wheel drive unit 30r correspond to the "drive unit", the brake unit 34 corresponds to the "braking unit", and the main ECU 40, the drive ECU 32, and the brake ECU 36 correspond to the "control unit".

[0027] The correspondence between the main elements of the embodiments and the main elements of the invention described in the "Means for Solving the Problem" section does not limit the elements of the invention described in the "Means for Solving the Problem" section, since the embodiments are examples for specifically explaining the mode for implementing the invention described in the "Means for Solving the Problem" section. In other words, the interpretation of the invention described in the "Means for Solving the Problem" section should be based on the description in that section, and the embodiments are merely specific examples of the invention described in the "Means for Solving the Problem" section.

[0028] The present disclosure has been described above using embodiments, but the present disclosure is not limited to these embodiments in any way, and it goes without saying that the present disclosure can be embodied in various forms within the scope that does not deviate from the gist of the present disclosure. [Industrial Applicability]

[0029] The present disclosure is applicable to the automobile manufacturing industry and the like. [Explanation of symbols]

[0030] 20 Automobile, 22f Front wheel drive shaft, 22r Rear wheel drive shaft, 24f, 24r Differential gear, 26a, 26b Front wheels, 27a, 27b Rear wheels, 30f Front wheel drive device, 30r Rear wheel drive device, 32 Drive electronic control unit (drive ECU), 34 Brake device, 36 Brake electronic control unit (brake ECU), 40 Main electronic control unit (main ECU), 41 CPU, 42 ROM, 43 RAM, 44 Flash memory, 51 Ignition switch, 52 Vehicle speed sensor, 53 Wheel speed sensor, 54 Acceleration sensor, 55 Accelerator pedal, 56 Accelerator pedal position sensor, 57 Brake pedal, 58 Brake pedal position sensor, 60 Shift electronic control unit (shift ECU), 61 Shift lever, 62 Shift position sensor, 63 Stop control request switch, 70 Display device, 72 communication device, 80 navigation device, 82 main body, 84 GPS antenna, 86 display.

Claims

[Claim 1] A drive device capable of applying drive force to some or all of the wheels; a braking device capable of applying braking force to each of the wheels; a control device that executes vehicle-stop control to control the drive device and the braking device so as to change the vehicle height or apply vibration to the vehicle while the vehicle is stopped; A motor vehicle comprising: the control device, when executing the vehicle-stop control, applies a driving force that gradually increases until a predetermined driving force is reached to at least some of the wheels to which the driving force is applied in the vehicle-stop control, and controls the drive device and the brake device so as to apply a sufficient braking force to the remaining wheels, and then executes the vehicle-stop control after confirming that no slip occurs in any of the wheels. A vehicle characterized by:

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