WO2015159750A1

WO2015159750A1 - Vehicle control device

Info

Publication number: WO2015159750A1
Application number: PCT/JP2015/060718
Authority: WO
Inventors: 和也奥村; 隼人吉川
Original assignee: トヨタ自動車株式会社
Priority date: 2014-04-15
Filing date: 2015-04-06
Publication date: 2015-10-22

Abstract

The objective of the present invention is to eliminate the feeling of discomfort associated with a control for increasing the transmission gear ratio when turning. This vehicle control device (12) performs a control whereby the transmission gear ratio of a transmission (6) connected to the output side of a drive power source (5) is increased so as to increase the deceleration force when a predetermined condition is satisfied, and whereby the increase in the deceleration force is stopped when the condition is no longer satisfied. The vehicle control device is configured so as to perform a transmission gear control (S9, S10) whereby, when the condition is satisfied and the transmission gear ratio is to be increased, the transmission gear ratio is controlled so as to be a value equal to or less than the transmission gear ratio capable of generating the requested drive power when the condition is no longer satisfied.

Description

Vehicle control device

The present invention relates to a control device that controls a driving force or a braking force of a vehicle by changing a gear ratio of a transmission connected to a driving force source.

Japanese Patent Application Laid-Open No. 2005-256636 discloses an apparatus configured to stabilize the behavior of a vehicle or improve the turning performance by controlling the driving force generated by the driving wheels when the vehicle turns. Yes. In the device described in Japanese Patent Application Laid-Open No. 2005-256636, a target value of the stability factor is obtained when the vehicle turns, and a basic required driving force requested by the driver is obtained, and the actual value of the stability factor is obtained. The basic required driving force is corrected so as to follow the target value.

Also, a device for controlling the braking force or driving force at the time of turning is described in Japanese Patent Laid-Open No. 2013-63733. The device described in Japanese Patent Laid-Open No. 2013-63733 has a sense of incongruity due to excessive or insufficient braking force or driving force or shock when the braking force or driving force is controlled to stabilize the behavior of the vehicle during turning. It is a device for the purpose of suppressing. Specifically, the change rate of the driving force is set based on the operation amount or the operation speed when the steering angle is increased or decreased. The greater the amount of change and the speed of change in the driving force, the more likely the driver feels uncomfortable. It becomes a large area. In the device described in Japanese Patent Application Laid-Open No. 2013-63733, the region where the uncomfortable feeling is unlikely is enlarged as the lateral acceleration increases.

Since the braking force and driving force of the vehicle also change depending on the gear ratio, the device described in Japanese Patent Application Laid-Open No. 2006-250337 determines whether or not deceleration is necessary based on the size of the front corner, and decelerates. In this case, the gear ratio is obtained. The necessity of deceleration is determined based on, for example, the estimated deceleration force and the limit lateral force obtained from the tire friction circle. If deceleration is required, a gear ratio corresponding to the deceleration is obtained. Can be secured.

According to the device described in each of the above patent publications, the braking force or driving force is controlled so as to improve the turning performance or stabilize the behavior of the vehicle. If the vehicle is in a so-called accelerator-off state where the accelerator pedal is not depressed during the turn, control for increasing the gear ratio may be performed to obtain a braking force. If the gear ratio is increased during cornering, the rotational speed of a driving force source such as an engine increases with an increase in the gear ratio.

Also, if the gear ratio is increased to increase the braking force or deceleration force when turning while the accelerator is off, if the accelerator pedal is depressed when exiting the corner, the gear ratio increase control is canceled. As a result, the gear ratio is reduced. When the gear ratio decreases, the rotational speed of the driving force source decreases. Therefore, control for decreasing the rotational speed of the driving force source is executed despite the acceleration operation. Therefore, even if the gear ratio can be increased to improve turning performance and behavior stability, the driver may feel uncomfortable, and there is room for technical improvement in this regard. .

The present invention has been made paying attention to the above technical problem, and has an object of suppressing a sense of incongruity associated with control of braking force or driving force for stabilizing the behavior of the vehicle during travel. .

In order to achieve the above object, the present invention increases the speed ratio of the transmission connected to the output side of the driving force source so as to increase the deceleration force when a predetermined condition is satisfied, In a vehicle control apparatus that performs control to end the increase of the deceleration force when the condition is no longer satisfied, the condition is not satisfied when the speed ratio is increased when the condition is satisfied. The speed ratio control is performed to control the speed to a value equal to or less than the speed ratio that can generate the required driving force.

In the present invention, the estimated control for estimating the driving force required when the condition is no longer satisfied, and the upper limit value when the speed ratio is increased by the satisfaction of the condition are estimated. Further, an upper limit value setting control obtained based on a speed ratio capable of generating a driving force is further performed, and the speed ratio control sets a speed ratio to be increased when the condition is satisfied, by setting the upper limit value. It can be set as the control set to the value below the upper limit calculated by control.

The present invention may be configured to further perform correction control for obtaining the driving orientation of the driver of the vehicle and correcting the upper limit value based on the driving orientation.

The driving orientation is at least one of the longitudinal acceleration of the vehicle, the lateral acceleration, the combined acceleration obtained by combining the longitudinal acceleration and the lateral acceleration, and the jerk which is a change rate of any one of these accelerations. The correction control may be obtained based on the control, and the upper limit value may be increased as the driving orientation in which the driving orientation causes the vehicle to be agile.

In addition to the above-described configuration, the present invention is further configured to further execute control for increasing the speed ratio based on information relating to a travel path on which the vehicle is traveling. In the case where the speed ratio increased by the establishment of the condition is added to the speed ratio increased based on the information on the information, the speed ratio after the addition is controlled to a value equal to or less than the upper limit value. It may be configured.

In addition to the above-described configuration, the present invention is configured to execute another upper limit value setting control for obtaining another upper limit value of the speed ratio so as to limit the deceleration force that increases when the condition is satisfied. The speed ratio control includes an upper limit value obtained by the upper limit value setting control based on a speed ratio capable of generating the estimated driving force, and another value obtained by the other upper limit value setting control. The transmission ratio may be controlled to a value that is equal to or less than a large upper limit value among the upper limit values.

In the present invention, the driving force estimated by the estimation control may be a driving force equal to a running resistance when the condition is no longer satisfied.

The above condition in the present invention may include that the required driving force becomes equal to or less than a predetermined value while the vehicle is traveling.

Alternatively, the above condition in the present invention may include that the required driving force becomes equal to or less than a predetermined value when the vehicle turns.

According to the present invention, when a predetermined condition is satisfied while the vehicle is traveling, the speed ratio is increased and the deceleration force is increased. The speed ratio by the increase control of the speed ratio is set to a speed ratio that is equal to or lower than the speed ratio that can generate the driving force required for the vehicle when the condition is no longer satisfied and the speed ratio is restored. Therefore, even if the above-mentioned condition is not satisfied and the gear ratio once increased is changed, the gear ratio does not change or slightly changes, and as a result, the driving force obtained with the gear ratio is increased. Since it is not particularly different from the required driving force, it is possible to suppress a sense of discomfort.

Further, if the upper limit value of the gear ratio is set to a value that can generate the estimated driving force required when the above condition is not satisfied, the rotational speed of the driving force source increases as the gear ratio increases. Even if it increases, the rotational speed is close to the rotational speed for obtaining the driving force required to maintain the traveling of the vehicle, so that the driver can be prevented from feeling uncomfortable.

In the present invention, the upper limit value is corrected in accordance with data representing the driving orientation of the driver, for example, acceleration or jerk of the vehicle. Accordingly, the driver's intention or driving intention can be reflected in the upper limit value, and the deceleration force according to the driver's intention or driving intention and the driving force after the termination of the increase control of the deceleration force can be obtained. .

Further, according to the present invention, the control for increasing the speed ratio based on the information on the traveling road such as that the traveling road is an uphill / downhill road or the road ahead obtained by the navigation system is a road with a continuous winding road is performed. If it is being executed, a gear ratio that is increased by the establishment of the condition is added. Since the added gear ratio is set or restricted based on the above-described upper limit value, it is possible to suppress such a sense of incongruity.

And in this invention, it can comprise so that two control may be performed as control which sets the upper limit at the time of increasing a gear ratio with predetermined conditions being satisfied, in that case, a small value of Since the gear ratio is controlled based on the upper limit value, it can be suppressed that the gear ratio becomes excessively large and uncomfortable.

In this invention, even if the above condition is not satisfied and the speed ratio is changed, at least the speed ratio is less than the speed ratio that generates the driving force corresponding to the running resistance. A sense of incongruity that decreases can be suppressed.

If the above conditions are such that the required driving force falls below a predetermined value, such as when the accelerator pedal is returned when the vehicle is traveling straight or turning, the driver's intended deceleration and turning performance can be obtained. In addition, it is possible to suppress the uncomfortable feeling that the rotational speed of the driving force source excessively increases or the driving force is insufficient when the required driving amount returns to a predetermined value or more.

It is a flowchart for demonstrating an example of control by the control apparatus of this invention. It is a time chart which shows an example of the change of the engine speed (speed ratio) at the time of performing control shown in FIG. It is a flowchart for demonstrating the other example of control by the control apparatus of this invention. It is a flowchart for demonstrating the further another example of control by the control apparatus of this invention. FIG. 6 is a time chart showing an example of changes in engine execution speed and gear ratio, and downhill control and turning control execution flags when the control shown in FIG. 4 is performed. FIG. It is a schematic diagram showing an example of a configuration of a vehicle and a control system to be controlled in the present invention.

The present invention will be described based on specific examples. The vehicle targeted by the present invention is a vehicle equipped with a transmission capable of appropriately changing the gear ratio by automatic control, and an example thereof is schematically shown in FIG. The vehicle Ve shown in FIG. 6 is a rear wheel drive in which the left and right front wheels 1 and 2 are steering wheels, the left and right

rear wheels

3 and 4 are drive wheels, and the

rear wheels

3 and 4 are driven by the power output from the engine 5. It is configured as a car.

The engine 5 is an internal combustion engine mounted on a conventional vehicle, and is configured such that its throttle opening, fuel injection amount, ignition timing, and valve timing can be electrically controlled. A transmission 6 is connected to the output side of the engine 5. This transmission 6 is a so-called automatic transmission that can appropriately change the gear ratio by electrical control, and is a stepped transmission mainly composed of a gear mechanism, a stepless type such as a belt type or a toroidal type. A transmission can be employed. In the hybrid vehicle, a power split mechanism (not shown) including a differential mechanism that splits the power output from the engine 5 into a motor / generator and an output member corresponds to the transmission according to the present invention. In the following description, a vehicle capable of continuously changing a gear ratio such as a vehicle equipped with a continuously variable transmission or a hybrid vehicle will be described as an example.

Each wheel 1 to 4 is provided with a

brake device

7, 8, 9, 10 respectively. These brake devices 7 to 10 have the same configuration as conventionally known brake devices, and are configured to operate by a brake operation by a driver and to operate by electrical control. A brake actuator 11 for operating the brake devices 7 to 10 is provided. As an example, the brake actuator 11 is a device for supplying hydraulic pressure to each of the brake devices 7 to 10 and discharging the hydraulic pressure. The brake actuator 11 electrically controls a control valve such as a solenoid valve, and performs predetermined control. The brake device 7 to 10 is configured to supply and discharge hydraulic pressure.

An electronic control unit (ECU) 12 is provided for controlling the engine 5, the transmission 6, the brake actuator 11, and the like. The electronic control unit 12 is mainly composed of a microcomputer, and performs calculations based on various types of input data, data stored in advance and programs, and uses the results of the calculations as control command signals for the engine 5 and the transmission 6. Alternatively, it is configured to output to the brake actuator 11. The data input to the electronic control unit 12 is a signal from a sensor disposed in each part of the vehicle Ve. For example, the sensor includes a depression angle (or depression amount or depression amount) of an accelerator pedal (not shown). An accelerator sensor 13 for detecting an accelerator opening), a brake sensor 14 for detecting a depression angle (or a depression amount) of a brake pedal (not shown), and a steering angle sensor 15 for detecting a steering angle of a steering wheel (not shown). , A wheel speed sensor 16 for detecting the rotational speeds (wheel speeds) of the

wheels

1, 2, 3 and 4, respectively, and before and after detecting acceleration (ie, longitudinal G in FIG. 6) in the longitudinal direction (vertical direction in FIG. 6) of the vehicle Ve. An acceleration sensor 17 and a lateral acceleration sensor 18 that detects an acceleration of the vehicle Ve in the axle direction (left-right direction in FIG. 6), that is, lateral acceleration (that is, lateral G). And the like yaw rate sensor 19 for detecting a yaw rate of the vehicle Ve. In addition, data acquired from the outside can be input to the electronic control device 12. For example, when a navigation system is installed, road information from a communication satellite, a sign post, a ground FM station, or the like can be received by the navigation system and the information can be input to the electronic control unit 12.

As an example, the control device is configured to control the driving force in order to stabilize the behavior of the vehicle Ve. In the vehicle Ve having the configuration shown in FIG. 6 described above, the driving force is output from the engine 5, so that the driving force is basically controlled by changing the throttle opening of the engine 5 based on the accelerator opening. . When the accelerator opening is equal to or less than a predetermined value, that is, approximately “0”, the driving force is further reduced by the engine 5 or the engine braking force (deceleration force) is further increased by the engine 5. Since it cannot be increased, the driving force is changed depending on the gear ratio. That is, the control device is configured to control the driving force or the deceleration force by controlling the engine 5 or the transmission 6. An example of control that stabilizes the behavior of the vehicle by increasing the deceleration force by such a gear ratio, or causes the target behavior, is to increase the deceleration force when turning, and the front wheels 1, which are steered wheels. 2 is a control (turning control) that increases the ground load and thereby improves the turning performance.

In speed ratio control to stabilize vehicle behavior or improve turning performance and other speed ratio control to change the speed ratio without being driven by the driver's operation, changes in vehicle speed, engine sound, etc. If the change is excessive or extreme, this is uncomfortable. The same applies when the gear ratio control is terminated. The control device performs the control shown in FIG. 1 as an example.

The control shown in FIG. 1 is repeatedly executed every predetermined short time while the vehicle Ve is traveling, for example, in the electronic control device 12 described above, or is repeatedly executed every predetermined short time during turning, or the turn control is performed. It is repeatedly executed when the execution condition is satisfied. First, a gear ratio is calculated from the accelerator opening and the vehicle speed (step S1). When the transmission 6 is a continuously variable transmission or a hybrid drive device that controls the engine speed by a motor / generator, the required driving force is determined based on the accelerator opening, the vehicle speed, and a map prepared in advance. The target engine output is determined from the required driving force and the vehicle speed, and the target engine speed for outputting the target engine output in a state with good fuel consumption is determined. Here, since the required driving force is obtained based on the accelerator opening under the vehicle speed at that time, the required driving force used in the control of the present invention may be the accelerator opening. A gear ratio is calculated from the target engine speed and the vehicle speed. Further, when a stepped automatic transmission is used as the transmission 6, a gear ratio (shift speed) is obtained based on a so-called shift diagram (shift map) prepared in advance.

On the other hand, the amount of change in the driving force (including the deceleration force that is a negative driving force; the same applies hereinafter) by turning control is calculated (step S2). The turning control is a control for setting the driving force so that the vehicle Ve travels along a target travel line when the vehicle Ve travels. One example is obtaining the target stability factor based on the steering angle, vehicle speed, longitudinal acceleration, etc., detecting the actual stability factor, and determining the acceleration so that the actual stability factor matches or follows the target stability factor. In this control, the driving force is set so as to generate the acceleration. Further, as described in Japanese Patent Laid-Open No. 5-278488, control may be performed in which a target yaw rate is obtained based on a steering angle and the driving force is set so that the actual yaw rate follows the target yaw rate. . In step S2, the driving force by such turning control is obtained, or the driving force change amount for achieving the driving force is obtained.

Next, a gear ratio by turning control is calculated based on the gear ratio obtained in step S1 and the driving force change amount obtained in step S2 (step S3). When turning, the lateral force is increased by increasing the load applied to the front wheels, and the turning performance is improved. Therefore, the driving force is decreased to increase the load applied to the front wheels. That is, the deceleration force is increased. This can be done by reducing the throttle opening and reducing the engine torque, but if the accelerator opening is less than a predetermined value such as “0”, the engine torque is further reduced. Therefore, the gear ratio is increased in order to increase the engine braking force (deceleration force). Therefore, in step S3, the speed ratio to be set when the speed reduction force is increased by changing the speed ratio is calculated. In other words, the gear ratio that is insufficient in the gear ratio obtained in step S1 is obtained, and the gear ratio obtained by adding the shortage to the gear ratio obtained in step S1 is the gear ratio obtained in step S3. .

If the transmission 6 is controlled so that the gear ratio obtained in step S3 is obtained, the engine braking force, that is, the deceleration force is increased by increasing the gear ratio. Further, the lateral acceleration is increased by the turn control. Such acceleration (deceleration and lateral acceleration) is obtained by adding the acceleration generated by increasing the gear ratio by turning control to the acceleration based on the operation of the driver. If it is large, the driver's operation and the acceleration that accompanies the driver's operation will not match the driver's consciousness, which may cause a sense of discomfort. Therefore, the first upper limit value A for the gear ratio is set so that the acceleration (front-rear G or combined acceleration) does not feel uncomfortable (step S4).

This upper limit value A corresponds to “another upper limit value” in the present invention, and can be set by the control described in Japanese Patent Laid-Open No. 2013-63733. This will be briefly explained. When the amount of change such as acceleration accompanying the operation of the steering wheel or brake is large, it is difficult for the driver to feel uncomfortable if the rate of change such as acceleration accompanying the operation is small. When the amount of change is small, it is difficult to feel uncomfortable even if the rate of change is large. Therefore, a region that does not cause a sense of incongruity can be set based on the change amount and the change speed associated with the above operation. In addition, when the lateral jerk, which is the steering angle, steering angular velocity, or lateral acceleration or lateral acceleration change rate, is large, the driver wants agile behavior change, or the agile behavior change is a normal behavior change. There is a high possibility of feeling that. In such a case, the above-described region can be expanded in the direction in which the above-described change amount and change rate are large. Conversely, if the steering angle, steering angular velocity, or lateral jerk, which is the rate of change of lateral acceleration or lateral acceleration, is small, the driver wants a so-called mild behavior change, or such a behavior change is normal. There is a high possibility that it is recognized as a change in behavior. In such a case, the region where the above-mentioned uncomfortable feeling is not reduced is the one in which the change amount and the change speed are smaller. Based on the region set in this way, the upper limit value A of the gear ratio is set so that the acceleration accompanying the increase in the gear ratio, that is, the change in the behavior of the vehicle Ve does not cause a sense of incongruity.

As an example, the control device estimates the “necessary driving force” when the control for increasing the deceleration force to improve the turning performance is completed, and the upper limit value B based on the estimated driving force. To function. The so-called increase control of the deceleration force is executed when the required driving force decreases to “0” or a predetermined value or less, such as returning the accelerator pedal as the vehicle turns, as described above. It is terminated by an increase in the required driving force such as depression of the accelerator pedal. That is, since the driver is seeking a “positive” driving force, the “necessary driving force” is a driving force required to maintain at least the vehicle speed. Since the driving force required to maintain the vehicle speed is a driving force equal to the running resistance (road / load), the gear ratio after changing the gear ratio increased by turning control by the end of the control is It is desirable that the gear ratio be a value that can obtain a driving force corresponding to the running resistance with the engine torque at that time.

As described above, since the increase control of the gear ratio by the turning control is finished when the driver performs an operation to increase the driving force, the change of the gear ratio and the accompanying driving force due to the end of the increasing control is determined by the driving. It is desirable that the force and the engine speed be changed at least so as not to decrease. In consideration of the desirable gear ratio to be set at the end of the gear ratio increase control and the mode of change thereof, in step S5, the upper limit value B of the gear ratio is set at the end of the gear ratio increase control. Set to a value based on the running resistance. Here, the value based on the running resistance is not only a value corresponding to the running resistance but also a predetermined value corresponding to the running resistance according to a request such as the characteristics of the vehicle Ve, a vehicle grade, or a request for improving fuel consumption. It is a value obtained by adjusting the value.

Also, the running resistance can be estimated by various methods known in the art. That is, the vehicle Ve accelerates or decelerates according to the driving force and the running resistance, and further maintains the vehicle speed. Therefore, the vehicle Ve can be obtained based on, for example, the vehicle speed and the steering angle when turning. Cornering resistance corresponding to the steering angle is generated, and the running resistance can be obtained from the decrease in vehicle speed that exceeds the decrease in vehicle speed due to the cornering resistance. Further, when the engine braking force is generated, the difference between the longitudinal acceleration corresponding to the engine braking force and the actual acceleration actually generated in the vehicle Ve becomes the acceleration due to the running resistance. Based on this, the running resistance can be obtained. Furthermore, it can obtain | require based on a vehicle speed and a lateral acceleration. The control for estimating the driving force corresponding to the running resistance in this way corresponds to the estimation control in the present invention.

On the other hand, in step S5, the upper limit value B of the gear ratio may be set in consideration of the engine speed. When the required driving force is less than the predetermined value, that is, when the vehicle is running with the accelerator pedal turned off, so-called accelerator-off, the engine braking force, that is, the deceleration force increases as the gear ratio increases, and the engine speed also increases. The number increases. And if the engine speed is excessively large, it may be uncomfortable. Accordingly, the upper limit value B of the gear ratio focusing on the deceleration force can be set based on the engine speed. In the control example shown in FIG. 1, the upper limit value of the gear ratio is determined by the engine speed in step S5. B is set.

The upper limit A obtained in step S4 and the upper limit B obtained in step S5 are compared (step S6). Then, a small upper limit value is adopted. Specifically, it is determined whether or not the upper limit value A is smaller than the upper limit value B in step S6. If the determination is affirmative, the upper limit value A is set as the final speed ratio upper limit value (step S7). On the other hand, if a negative determination is made in step S6, the upper limit value B is set as the final gear ratio upper limit value (step S8). The speed ratio by turning control is limited by the final speed ratio upper limit value thus adopted (step S9). Then, the limited transmission gear ratio is output (step S10). That is, when the gear ratio is increased (when downshifting) when the required driving force that can be expressed by the accelerator opening is less than a predetermined value when turning, the gear ratio exceeds the final gear ratio upper limit value. There is nothing.

Therefore, if the final speed ratio upper limit value is adopted as the upper limit value B and the speed ratio calculated in step S3 is equal to or higher than the upper limit value B, the speed ratio to be set becomes the upper limit value B. . This upper limit value B is a value capable of generating a driving force corresponding to the running resistance estimated when the control for increasing the gear ratio is completed by the turning control. For this reason, for example, even when the accelerator pedal is depressed and the required driving force increases, and the increase control of the gear ratio is terminated, the driving force corresponding to the running resistance is generated without changing the gear ratio. A situation in which the driving force is reduced against the intention of the person or the engine speed is reduced is avoided or suppressed. In addition, since it is considered that the driver intends to continue traveling, the driving state that generates the driving force corresponding to the traveling resistance is not contrary to the driver's intention or does not greatly deviate. Increasing the ratio to the upper limit B does not cause discomfort.

Further, if the final gear ratio upper limit value is the upper limit value A and the gear ratio calculated in step S3 is equal to or higher than the upper limit value A which is the final gear ratio upper limit value, the speed change to be set is performed. The ratio is the upper limit value A. In other words, the gear ratio during turning control is the upper limit value A, which is smaller than the upper limit value B based on the engine speed. Therefore, for example, when the accelerator pedal is depressed and the required driving force increases, and thus the gear ratio increase control is terminated, the required driving force at that time is a driving force that is higher than the vehicle speed, that is, a driving force corresponding to a running resistance. Because of the above driving force, the gear ratio increases from the upper limit value A to a gear ratio (and engine speed) at which the driving force can be generated. Such an increase in driving force or engine speed is in accordance with the driver's intention that appears as an increase in the accelerator opening, so that there is no sense of incongruity.

Furthermore, even if the final gear ratio upper limit value is either the upper limit value A or the upper limit value B, if the gear ratio calculated in step S3 is smaller than the final gear ratio upper limit value, the accelerator pedal is depressed. As a result, the required driving force increases, and as a result, when the control of the gear ratio by turning control is completed, the gear ratio increases to a gear ratio that generates a driving force corresponding to the driving resistance at that time or a driving force higher than that. Be made. Such an increase in driving force or engine speed is in accordance with the driver's intention that appears as an increase in the accelerator opening, so that there is no sense of incongruity.

FIG. 2 is a time chart showing changes in the engine speed Ne when the control shown in FIG. 1 is performed. Here, the change in the engine speed Ne is generally indicated by controlling the engine speed Ne toward the target value in the vehicle Ve configured to continuously change the gear ratio. This is because the gear ratio is switched as a result of the control of the engine speed Ne. Since the engine speed can be expressed as a product of the speed corresponding to the vehicle speed such as the output speed of the transmission 6 and the speed ratio, the change in the engine speed Ne shown in FIG. 2 is replaced with the change in the speed ratio. be able to. In the example shown in FIG. 2, the accelerator pedal is returned before the corner and the accelerator opening becomes below a predetermined value such as “0”, and in this state, the vehicle enters the corner and the steering angle increases. This is an example when the accelerator pedal opening is increased due to depression. The turning control is started at time t1 when the steering angle increases, and the driving force change amount or the driving force required during turning is calculated, and the upper limit value A and the upper limit value B described above are calculated. The engine speed Ne is increased so as to generate the calculated driving force, which becomes a gear ratio.

When the engine speed Ne (speed ratio) obtained by the turning control is larger than the upper limit value B as shown by the broken line in FIG. 2, the engine speed Ne, that is, the speed ratio is limited to the upper limit value B. By performing such limit control, the driving force (deceleration force) generated in the vehicle Ve becomes smaller than the required value by the turning control. In order to compensate for the shortage, for example, the braking devices 7 to 10 may be operated to increase the deceleration force. In this case, if the brake devices 7 to 10 for the inner wheel (particularly the rear inner wheel) at the time of turning are operated, turning performance can be increased with a small braking force. As described above, the upper limit value B is a gear ratio that can estimate the running resistance after passing through a corner or at the end of turning control, and can generate a driving force corresponding to the estimated value. It is intended to continue running. Accordingly, the operating state of the engine 5 capable of generating a driving force corresponding to the estimated running resistance is an operating state within a range assumed by the driver, and therefore the speed ratio is increased to the upper limit value B. There is no particular discomfort.

When the vehicle Ve reaches or exits from the corner and the driver performs a required driving force increase operation such as depressing the accelerator pedal (at time t2), the accelerator opening increases, and accordingly, the shift is controlled by turning control. The ratio increase control ends. As a result, the engine speed, that is, the gear ratio, is set to the engine speed or the gear ratio according to the vehicle speed and the accelerator opening at that time. The driving force required at this time is a driving force equal to or greater than the driving force corresponding to the running resistance. On the other hand, the speed ratio increased by the turning control is a speed ratio determined based on the upper limit value B that can generate the driving force corresponding to the estimated running resistance. Therefore, even if the gear ratio is changed by the end of the turn control, if the gear ratio obtained based on the vehicle speed or the accelerator opening at that time is such that the driving force corresponding to the running resistance is generated, When the turning control ends, the gear ratio does not change particularly. Further, if the speed change ratio obtained based on the vehicle speed and the accelerator opening is a speed change ratio necessary for accelerating the vehicle Ve, the speed change ratio is increased when the turn control is completed. According to the said control apparatus, when turning control is complete | finished, a gear ratio, an engine speed, and a driving force function so that it may suppress at least falling. In other words, since a change such as a gear ratio contrary to the operation of the driver intended to increase or maintain the driving force does not occur, it is avoided or suppressed that the driver feels uncomfortable.

The example shown in FIG. 2 is an example of the vehicle Ve that can continuously change the speed ratio, and therefore the speed ratio or the engine speed Ne limited by the upper limit value B is estimated at the end of the turn control. It almost coincides with the speed ratio or engine speed Ne that generates the driving force corresponding to the travel resistance. However, in a vehicle equipped with a stepped transmission, the gear ratio that can generate a driving force corresponding to the estimated running resistance is a gear ratio that is a value between predetermined gears. There is. In such a case, the gear position having a value smaller than the calculated gear ratio is selected and set.

Incidentally, the driving force set at the time when the turning control is completed is a driving force equal to or higher than the driving force corresponding to the running resistance estimated to occur at that time. This is to prevent a change in driving force against an operation that increases the required driving force. Therefore, more preferably, it is conceivable to set the driving force as close as possible to the driving force intended by the driver, or the speed ratio for generating the driving force or the engine speed during the turning control. That is, the driver who performs agile driving operates the accelerator so as to generate a relatively large driving force at the end of the turning control, and conversely, the driver who performs a so-called mild driving relatively moves at the end of the turning control. There is a tendency to perform an accelerator operation so as to generate a small driving force. It is conceivable that the driving force at the end of the turn control is estimated in consideration of such so-called driving orientation, and the upper limit value B is set based on the estimation result.

FIG. 3 is a flowchart for explaining an example of the control, and the example shown here is an example in which the upper limit value B in the control example shown in FIG. 1 is corrected based on the driving orientation. Driving orientation can be determined based on longitudinal acceleration (front-rear G) and longitudinal jerk at the entrance of the corner, synthetic acceleration or rate of change thereof (synthetic jerk), or an on / off signal of a switch for selecting a sports mode. . For example, if the absolute value of the longitudinal acceleration or the jerk is greater than a predetermined threshold during a certain time before the start of steering, it will be before and after the accelerator pedal is depressed (when the accelerator is on). It is determined that the driving tendency has a strong tendency of sports driving to increase acceleration or front and rear jerk. As another example, if the absolute values of lateral acceleration and lateral jerk during steering are greater than a predetermined value, the longitudinal acceleration when the accelerator pedal is depressed (when the accelerator is on) or It is determined that the driving tendency has a strong tendency of sports driving to increase the front and rear jerk. Still another example is an example described in JP2013-163514A. The method described in Japanese Patent Application Laid-Open No. 2013-163514, for example, synthesizes the absolute values of the longitudinal acceleration and the lateral acceleration from moment to moment to obtain a combined acceleration to obtain an instantaneous value and hold the instantaneous value, When the newly obtained instantaneous value is larger than the already held instantaneous value, the newly obtained large instantaneous value is held as the instruction value. Then, the state where the sequentially obtained instantaneous value is smaller than the instruction value continues, and the predetermined value is satisfied during that time, the instruction value is decreased. And it determines with the driving | running | working orientation with a strong tendency of sport running, so that the instruction | indication value is large. The driving orientation may be determined or calculated by a conventionally known method other than the method described above.

Then, the upper limit value B calculated in step S5 is corrected based on the data indicating the driving orientation (step S51), and then the process proceeds to step S6. The correction is a correction that increases the upper limit value B as the acceleration or jerk increases, or as the sport mode is selected, in other words, as the driving direction of the sport driving is stronger. The correction amount can be obtained by the following equation, for example.
(Corrected driving force) = (Deceleration at the corner entrance) x (vehicle weight) x k
The coefficient k may be a value learned during traveling based on a value determined by experiments or simulations. Further, since the correction amount determines the characteristics or character of the vehicle, the correction amount may be set to a predetermined value in advance in design according to the type, power performance, vehicle speed, steering angle, and the like of the target vehicle Ve. . The upper limit value B is corrected by adding the corrected driving force obtained in this way to the “required driving force” for maintaining the vehicle speed described above. Other control steps in FIG. 3 are the same as those in the example shown in FIG. 1, and therefore, the same reference numerals as those in FIG.

When such control shown in FIG. 3 is performed, the upper limit value of the engine speed Ne or the gear ratio varies depending on the driving orientation and is close to the engine speed Ne or the gear ratio at the end of the turning control. Become. If this is also shown in FIG. 2, it will be indicated by a one-dot chain line or a two-dot chain line. Therefore, the engine speed Ne and the gear ratio, which are limited by the upper limit value B during the turning control, do not feel strange, and the engine speed Ne and the gear ratio do not change with the end of the turning control. Moreover, even if it changes, it does not become a change different from the driver's intention, so that a sense of discomfort can be prevented or suppressed.

Still another example of control executed by the control device according to the embodiment of the present invention will be described. In addition to the turning control described above, control based on information relating to a traveling road, such as road surface gradient, is known as control for changing the engine speed and the gear ratio in the vehicle Ve without the driver's operation. For example, when traveling on a downhill road, control for increasing the gear ratio in order to increase engine braking force and control for appropriately changing the gear ratio based on road information obtained by a navigation system are known. When such control relating to the travel path and control for setting the speed ratio by the turning control or the upper limit value of the engine speed Ne are superimposed, the control device according to the present invention executes the control shown in FIG. It is configured.

The control example shown in FIG. 4 is obtained by adding a new control step to the control example shown in FIG. 3 described above. In addition to calculating the gear ratio based on the accelerator opening and the vehicle speed (step S1), the control example shown in FIG. A gear ratio by slope control is calculated (step S11). As is known in the art, the uphill / downhill control is increased when it is detected that the vehicle Ve is traveling on the downhill road or the uphill road and it is determined that the braking force or the driving force is necessary. This is control for limiting shift or executing downshift. Therefore, the gear ratio in step S11 may be a control for receiving or reading the gear ratio in the uphill / downhill control executed as another control routine.

In step S2, the amount of change in the driving force (negative driving force, deceleration force) due to the turning control is calculated as described above, and a shift for obtaining the amount of change (that is, the deceleration force to be set in the turning control). The ratio is obtained based on the transmission ratio by the uphill / downhill control (step S31). More specifically, a speed ratio obtained by adding a speed ratio increased by turning control to a speed ratio increased by uphill / downhill control is obtained.

Then, in the same manner as described with reference to FIG. 1 or FIG. 3, the final speed ratio upper limit value is the upper limit value A or the upper limit value described above in step S4, step S5, step S51, step S6, step S7, and step S8. B is set. In the control example shown in FIG. 4, the upper limit value B is corrected based on the deceleration at the corner entrance in step S51. The final speed ratio upper limit value set here is an upper limit value for limiting the speed ratio calculated in step S31. That is, when the gear ratio control is performed in the turning control in addition to the gear ratio control in the uphill / downhill control, the longitudinal acceleration or the acceleration obtained by combining the longitudinal acceleration and the lateral acceleration is not uncomfortable, and the turning control is not performed. This is to limit the speed ratio or the engine speed Ne during the uphill / downhill control and the turn control so that the change in the speed ratio or the engine speed Ne at the end does not cause a sense of incongruity. The control of step S4, step S5, step S51, step S6, step S7 and step S8 is configured to be executed in parallel with the control of step S1, step S11, step S2 and step S31 described above. May be.

After the final gear ratio upper limit value is set to the upper limit value A or the upper limit value B, the gear ratio obtained by the up / down slope control is compared with the final gear ratio upper limit value (step S90). When the final speed ratio upper limit value is larger than the speed ratio by the uphill / downhill control, the speed ratio at the time of traveling in which the uphill / downhill control and the turn control are executed is limited by the final speed ratio upper limit value (step S91). . On the other hand, when the speed ratio by the uphill / downhill control is larger than the final speed ratio upper limit value, the speed ratio at the time of traveling in which the uphill / downhill control and the turn control are executed is limited by the speed ratio by the uphill / downhill control (Step S92). That is, the speed ratio is limited by a larger value of the speed ratio by the up / down slope control and the final speed ratio upper limit value. Then, a gear ratio having a value equal to or smaller than the limited gear ratio is output (step S10). Other control steps in FIG. 4 are the same as those in the example shown in FIG. 3, and therefore, the same reference numerals as those in FIG.

Therefore, when the gear ratio is further controlled by the turn control in the state where the uphill / downhill control is being executed by performing the control as shown in FIG. 4, the engine speed is excessively increased by the turn control or the turn control is performed. It is possible to prevent or suppress a sense of incongruity such as a shift or engine speed change contrary to the driver's operation at the end. Further, since the transmission ratio by the uphill / downhill control can be ensured, a desired driving force or deceleration force can be obtained, and in addition, the turning performance during the uphill / downhill control can be improved.

FIG. 5 is a time chart showing changes in the gear ratio, the engine speed Ne, and the flags for each control when the control shown in FIG. 4 is performed. The example shown here is an example in which downhill control is executed, and it is determined that the vehicle is traveling on a downhill road and the braking force is obtained while traveling at a predetermined accelerator opening and vehicle speed. Downhill control is started (time t11). That is, the downhill control execution flag is turned on, the gear ratio is increased to a predetermined value by downhill control, and the engine speed Ne increases accordingly. When a change such as an increase in the steering angle is detected in a state where the gear ratio and the engine speed Ne are increased to the predetermined values by the downhill control, the turning control is started (time t12). That is, the turning control execution flag is turned on, and the gear ratio and the engine speed Ne are increased. Since the gear ratio obtained by the turn control or the increase in the engine speed Ne is added to the gear ratio increase by the downhill control, the calculated gear ratio is as shown by a broken line in FIG. 5, for example.

When the turning control is started, the above-described upper limit value A and upper limit value B and the final gear ratio upper limit value based on these are obtained. And the final gear ratio by turning control during uphill / downhill control is limited by the final gear ratio upper limit value or the gear ratio by uphill / downhill control. The example shown in FIG. 5 is an example when the final speed ratio upper limit value is larger than the speed ratio by the uphill / downhill control, and therefore the speed ratio and the engine speed Ne when the turn control is executed together with the uphill / downhill control are as follows. It is set as shown by a solid line in FIG. Note that the gear ratio and the engine speed when the turning control is completed change in the same manner as in the example shown in FIG. 2 described above, and are omitted in FIG.

Here, the relationship between the present invention and the above-described specific example will be briefly described. The control for estimating the running resistance in step S5 described above corresponds to the estimation control in the present invention, and also corresponds to the running resistance in step S5. The control for obtaining the speed ratio capable of generating the driving force to be generated corresponds to the upper limit value setting control in the present invention. Further, the final speed ratio upper limit value is set with the upper limit value B at the above-described step S9, and the final value at step S10 Control for setting the speed ratio limited by the speed ratio upper limit corresponds to the speed ratio control in the present invention.

1, 2 ... Front wheel, 3, 4 ... Rear wheel, 5 ... Engine, 6 ... Transmission, 7, 8, 9, 10 ... Brake device, 11 ... Brake actuator, 12 ... Electronic control unit (ECU), 13 ... Accelerator Sensor: 14 ... Brake sensor, 15 ... Steering angle sensor, 16 ... Wheel speed sensor, 17 ... Longitudinal acceleration sensor, 18 ... Lateral acceleration sensor, 19 ... Yaw rate sensor, Ve ... Vehicle.

Claims

The transmission ratio of the transmission (6) connected to the output side of the driving force source (5) is increased so as to increase the deceleration force when a predetermined condition is satisfied, and the condition is not satisfied. In the vehicle control device (12) for performing the control to end the increase of the deceleration force by
Gear ratio control for controlling the gear ratio when the gear ratio is increased when the condition is satisfied to a value equal to or less than the gear ratio capable of generating the driving force required when the condition is not satisfied. A vehicle control device configured to perform (S9).
In the vehicle control device (12) according to claim 1,
Estimation control (S5) for estimating a driving force required when the condition is not satisfied;
Further performing upper limit value setting control (S5) for obtaining an upper limit value when the speed ratio is increased when the condition is satisfied based on a speed ratio capable of generating the estimated driving force; and The speed ratio control (S9) is a control for setting a speed ratio to be increased when the condition is satisfied to a value equal to or lower than the upper limit value obtained in the upper limit value setting control (S5). Control device.
In the vehicle control device (12) according to claim 2,
The vehicle control device is further configured to perform correction control (S51) for obtaining a driving orientation of the driver of the vehicle and correcting the upper limit value based on the driving orientation.
In the vehicle control device (12) according to claim 3,
The driving orientation is at least one of the longitudinal acceleration of the vehicle, the lateral acceleration, the combined acceleration obtained by combining the longitudinal acceleration and the lateral acceleration, and jerk which is a change rate of any of these accelerations. Based on
The correction control (S51) includes a control for increasing the upper limit value as the driving orientation in which the driving orientation causes agile behavior in the vehicle is stronger.
In the vehicle control device (12) according to claim 2,
It is configured to further execute control (S31) for increasing the speed ratio based on information on a travel route on which the vehicle is traveling,
The speed ratio control (S91, S92) is performed when the speed ratio increased by the establishment of the condition is added to the speed ratio increased based on the information on the travel path. A vehicle control apparatus configured to control a gear ratio to a value equal to or less than the upper limit value.
In the vehicle control device (12) according to claim 2,
Another upper limit value setting control (S4) for obtaining another upper limit value of the gear ratio so as to limit the deceleration force that increases when the condition is satisfied,
The speed ratio control (S9) includes the upper limit value obtained in the upper limit value setting control (S5) based on the speed ratio capable of generating the estimated driving force, and the other upper limit value setting control ( A vehicle control apparatus configured to control the speed ratio to a value equal to or less than a large upper limit value among the other upper limit values obtained in S4).
In the vehicle control device (12) according to any one of claims 2 to 6,
The vehicle control apparatus characterized in that the driving force estimated in the estimation control (S5) is a driving force equal to a running resistance when the condition is not satisfied.
In the vehicle control device (12) according to any one of claims 1 to 7,
The vehicle control apparatus according to claim 1, wherein the condition includes that the required driving force becomes equal to or less than a predetermined value during traveling of the vehicle.
In the vehicle control device (12) according to any one of the preceding claims,
The condition includes that the required driving force is equal to or less than a predetermined value when the vehicle is turning.