JP6229701B2 - Driving force control device - Google Patents

Description

  The present invention relates to a driving force control device that controls a driving force of a vehicle by changing an output of a driving force source and a gear ratio of an automatic transmission.

  Patent Document 1 describes a vehicle control device including an engine and an automatic transmission that can be controlled without depending on a driver's accelerator operation. In the control device described in Patent Document 1, a target acceleration after the acceleration of the vehicle is set at the time of accelerator depression for starting or accelerating is set, and the actual acceleration follows the target acceleration. Output is controlled. The target acceleration is obtained on the basis of the history of acceleration data at the time of actual acceleration rising and the intention (driving orientation) of the driver to travel.

  Patent Document 2 discloses a vehicle control for the purpose of improving drivability at the time of reacceleration (for example, acceleration performance according to reacceleration intention) by appropriately setting a gear ratio according to the intention of deceleration. An apparatus is described. In the control device described in Patent Document 2, the gear ratio of the automatic transmission is determined based on the deceleration during deceleration traveling. Specifically, the required drive amount at the time of reacceleration is obtained based on the deceleration during deceleration traveling, and the gear ratio of the automatic transmission that can realize the requested drive amount is obtained. Based on the time integral value of deceleration until the peak value of deceleration during deceleration traveling is obtained after the control start condition for determining the gear ratio is satisfied, the drive request amount at the time of reacceleration is corrected. .

  Patent Document 3 describes a vehicle control device that aims to improve drivability by using behavior characteristics that accurately reflect the traveling environment and driving orientation of the vehicle. In the control device described in Patent Document 3, an index based on the traveling state of the vehicle is obtained, and the traveling characteristics of the vehicle are changed according to the index. When the index is changed, the index is quickly changed in the direction in which the vehicle traveling agility increases, and is slowly changed in the direction in which the vehicle traveling agility decreases.

JP 2009-262838 A JP 2013-185696 A JP 2011-207463 A

  The control device described in Patent Document 1 is intended to improve the feeling of acceleration of the vehicle in the latter half of the acceleration travel after the acceleration peak value. Therefore, in the control device described in Patent Document 1, the target acceleration is set using the history of acceleration data at the time of acceleration rising. The target acceleration is changed according to the driving orientation of the driver. The driving orientation is switched between a normal mode (normal traveling orientation) and a power mode (sport traveling orientation) based on a switch switching operation or a driver's accelerator operation. In the power mode, a larger target acceleration is set over a longer period than in the normal mode. Therefore, according to the control device described in Patent Document 1, even when the driver's driving orientation changes from the normal mode to the power mode, an appropriate target acceleration that reflects the driving orientation change is set. Thus, it is possible to obtain an appropriate vehicle acceleration performance in the power mode.

  However, the control device described in Patent Literature 1 does not consider a case where the driver's driving orientation changes to a driving orientation (fuel consumption traveling orientation) that emphasizes fuel efficiency and efficiency more than usual. That is, in the control device described in Patent Document 1, although the driving orientation corresponds to the case where the driving orientation changes between the normal driving orientation and the sports driving orientation, the driving orientation is changed from the normal driving orientation to the sports driving orientation. The case of changing to the opposite fuel efficiency driving orientation has not been considered. Therefore, when the driving orientation changes from the normal driving orientation to the fuel efficiency driving orientation, the driver will drive at an acceleration larger than the acceleration intended or predicted by the driver, resulting in the driver feeling uncomfortable. There is a possibility that.

  The present invention has been conceived by paying attention to the technical problem described above, and is intended for a vehicle equipped with an automatic transmission. It is an object of the present invention to provide a driving force control device that can re-accelerate a vehicle with an appropriate driving force that reflects driving orientation.

  In order to achieve the above object, the present invention relates to a vehicle driving force including an engine, a driving wheel, and an automatic transmission that transmits torque between the engine and the driving wheel. The driving force control device that controls the driving force includes a controller that controls the driving force, and the controller stores the vehicle speed and acceleration of the vehicle during acceleration traveling before the vehicle travels at a reduced speed. The acceleration history line is calculated using the correlation, and the acceleration history line is updated each time the acceleration travels, and the vehicle is within a deceleration range closer to 0 than the predetermined deceleration on the negative acceleration side. When the vehicle decelerates at a deceleration, or when the vehicle travels at a constant speed within an acceleration range including positive acceleration and negative acceleration, the vehicle is more than the acceleration history line. And a provisional line in which both the accelerations are reduced, and the vehicle re-accelerates based on the acceleration history line or the provisional line as a target vehicle speed for reacceleration after the vehicle decelerates. Based on the current vehicle speed and the expected vehicle speed, an acceleration at the time of reacceleration, which is used as a control index when the vehicle is reaccelerated, is set based on the current vehicle speed and the expected vehicle speed. The automatic transmission is configured to set a speed ratio of the automatic transmission that can realize the acceleration at the time of reacceleration based on the acceleration at the time of reacceleration before the vehicle starts the reacceleration running, and The vehicle speed is a value included in a predetermined range close to the latest acceleration history line when the vehicle speed and the acceleration in the latest travel data are larger than the latest acceleration history line. In a case where the vehicle speed and the acceleration in the latest travel data are set based on the acceleration history line and are smaller than the latest acceleration history line and are not included in the predetermined range. Further, it is set based on the provisional line.

  Further, the present invention is characterized in that the controller clears the provisional line when setting the expected vehicle speed based on the acceleration history line.

  Further, the present invention is characterized in that the controller sets the provisional line by lowering the acceleration history line by a predetermined distance in a direction in which both the vehicle speed and the acceleration become smaller than the acceleration history line. Yes.

  Further, the present invention is characterized in that the controller sets the provisional line as a straight line including at least two times of the travel data within a most recent period that is a predetermined number of times after the latest acceleration travel.

  Further, according to the present invention, the controller includes the travel data of one time in the most recent period that is a predetermined number of times after the latest acceleration travel, and the temporary line is defined as a straight line having the same slope as the acceleration history line. It is characterized by setting.

  The present invention is characterized in that the controller corrects the temporary line so that a divergence between the temporary line and the latest traveling data is reduced by bringing the temporary line closer to the latest traveling data. It is said.

  In the driving force control device according to the present invention, the automatic transmission capable of accelerating the vehicle with the acceleration at the time of reacceleration before the reacceleration running is started at the time of reacceleration after the deceleration running. A gear position (or gear ratio) is set. The acceleration at the time of reacceleration is an acceleration expected by the driver at the time of reacceleration after the deceleration traveling, and is a control index in driving force control at the time of reacceleration. The acceleration at the time of reacceleration is obtained based on the expected vehicle speed estimated as the vehicle speed desired by the driver during the reacceleration running. The expected vehicle speed is obtained by calculating a correlation line or approximate line between the acceleration at the time of reacceleration and the vehicle speed based on the traveling data at the time of previous acceleration traveling. Therefore, the expected vehicle speed is calculated as an estimated value reflecting the driver's intention and driving intention.

  Since the acceleration at the time of reacceleration is obtained based on the expected vehicle speed as described above, the acceleration at the time of reacceleration can be used as a control index for shift control reflecting the driver's intention, driving orientation, and the like. Therefore, at the start of reacceleration after deceleration, the automatic transmission can set a gear ratio that can obtain the driving force necessary for reacceleration. Further, the gear ratio set at that time is a gear ratio that is estimated to be able to accelerate the vehicle at an acceleration intended by the driver or an acceleration requested by the driver.

  Therefore, according to the driving force control apparatus of the present invention, for example, since the downshift during the deceleration traveling is insufficient, the downshift is further performed to compensate for the lack of the driving force during the reacceleration traveling after the deceleration traveling. It is possible to appropriately accelerate the vehicle while avoiding breakage. For this reason, it is possible to suppress the driver from feeling uncomfortable or shock, and to improve the acceleration performance and acceleration feeling of the vehicle.

  As described above, in the driving force control apparatus of the present invention, the expected vehicle speed that reflects the driver's driving orientation is obtained based on the travel data acquired during the previous acceleration travel. Specifically, an acceleration history line is calculated based on the travel data, and an expected vehicle speed is obtained based on the acceleration history line. When the vehicle travels at an accelerated speed, the driver's driving orientation tends to be stronger in a sports driving orientation that prioritizes the power performance of the vehicle than a fuel consumption traveling orientation that prioritizes the fuel efficiency and energy efficiency of the vehicle. On the other hand, for example, during slow deceleration traveling where the negative acceleration of the vehicle, that is, deceleration, is less than a predetermined value, or during steady traveling where almost no acceleration occurs, the driving orientation is more fuel intensive than sports driving. Tend. On the other hand, in the driving force control apparatus according to the present invention, when the vehicle travels at a slow deceleration speed as described above or at a steady speed, a provisional line with a reduced acceleration history line is set. And the expected vehicle speed is calculated | required based on the provisional line. Therefore, even when the vehicle is traveling slowly decelerating or steady, and the driving orientation is predicted to change to the fuel consumption driving orientation, the change in driving orientation can be appropriately reflected in the control.

  Further, in the driving force control apparatus of the present invention, when the provisional line is set as described above, the acceleration history line is compared with the latest traveling data in order to verify the estimation accuracy of the provisional line. The When the latest travel data is larger than the acceleration history line, or when the latest travel data is within a predetermined range near the acceleration history line, that is, a value included in the predetermined range, the provisional line estimation accuracy is not good. The expected vehicle speed is determined using the acceleration history line. If the latest traveling data is outside the predetermined range near the acceleration history line, that is, a value not included in the predetermined range and is smaller than the acceleration history line, it is determined that the estimation accuracy of the provisional line is good, Expected vehicle speed is calculated using a temporary line. Therefore, according to the driving force control apparatus of the present invention, the expected vehicle speed can be appropriately set according to the estimated accuracy of the provisional line. Therefore, the driving force of the vehicle can be controlled by appropriately reflecting the driver's intention and driving intention.

  Further, according to the driving force control device of the present invention, as a result of verifying the estimation accuracy of the provisional line as described above, when the expected vehicle speed is set using the acceleration history line without adopting the provisional line, the provisional line Is cleared. For this reason, it is possible to reduce the load on the memory for storing data and the load on the arithmetic processing.

  Further, according to the driving force control device of the present invention, for example, the temporary line as described above is set by translating the acceleration history line by a predetermined distance on the graph showing the acceleration history line. The Therefore, the provisional line can be set accurately and easily by obtaining an appropriate predetermined distance by experiment, simulation, or the like.

  Further, according to the driving force control apparatus of the present invention, the provisional line as described above is set by using at least two times of travel data in the latest period. Therefore, the provisional line can be set with high accuracy based on as little data as possible.

  Further, according to the driving force control apparatus of the present invention, by using the slope of the acceleration history line calculated for obtaining the expected vehicle speed, the latest traveling data or the latest traveling data within the latest period can be used. The provisional line as described above is set. Therefore, it is possible to easily set a provisional line based on the latest and minimum one-time data.

  According to the driving force control apparatus of the present invention, as described above, when a provisional line is set, the estimation accuracy of the provisional line is verified. If it is determined that the estimation accuracy of the provisional line is good, the provisional line is corrected based on the latest travel data, and the expected vehicle speed is set by using the corrected provisional line with further improved accuracy. Is done. Therefore, the intention and driving orientation of the driver can be reflected in the control with higher accuracy.

It is a figure which shows an example of the structure of the vehicle used as the object of control by this invention, and a control system. It is a flowchart for demonstrating an example of basic driving force control by the driving force control apparatus of this invention. It is a figure for demonstrating the correlation of the "acceleration at the time of reacceleration" calculated | required in order to calculate the "expected vehicle speed" and the "acceleration at the time of reacceleration" in the driving force control of this invention, and a vehicle speed. It is a figure for demonstrating the correlation line (approximate line) in the correlation shown in FIG. It is a figure for demonstrating an example of the control map for calculating | requiring "acceleration at the time of reacceleration" in the driving force control of this invention. It is a figure for demonstrating the control which calculates | requires the gear stage (speed ratio) which can output "output possible acceleration" and its output possible acceleration in the driving force control of this invention. It is a block diagram for demonstrating the structure of the controller which performs the driving force control of this invention. It is a figure for demonstrating the behavior (vehicle speed, acceleration, engine speed, etc.) of a vehicle at the time of performing the driving force control of this invention targeting the vehicle carrying a continuously variable transmission. It is a figure for demonstrating the calculation method of the approximate line of driving | running | working data regarding the control which weights with respect to the driving | running | working data for calculating | requiring "expected vehicle speed" and "acceleration at the time of reacceleration." It is a figure for demonstrating the effect of the weighting with respect to said driving | running | working data. In the driving force control of the present invention, the control is to estimate the “expected vehicle speed” and “acceleration during reacceleration” using the “acceleration history line” and “provisional line”, and an example of characteristic control of the present invention It is a flowchart for demonstrating. FIG. 12 is a diagram for explaining an example of control for verifying the estimation accuracy of a “provisional line” when executing the control shown in the flowchart of FIG. 11. FIG. 12 is a diagram for explaining another example of the control for verifying the estimation accuracy of the “provisional line” when the control shown in the flowchart of FIG. 11 is executed. In the driving force control of the present invention, the control is to estimate the “expected vehicle speed” and “acceleration during reacceleration” using the “acceleration history line” and “provisional line”. It is a flowchart for demonstrating an example. FIG. 15 is a diagram for describing an example of control for improving estimation accuracy by correcting a “provisional line” when executing the control shown in the flowchart of FIG. 14. FIG. 15 is a diagram for explaining another example of the control for estimating the “provisional line” and improving the estimation accuracy when the control shown in the flowchart of FIG. 14 is executed.

  Next, an embodiment of the present invention will be described with reference to the drawings. A vehicle to which the present invention can be applied is a vehicle equipped with an automatic transmission capable of shifting the power output from an engine and transmitting it to drive wheels. The automatic transmission according to the present invention may be a continuously variable transmission capable of continuously changing a gear ratio, such as a belt type continuously variable transmission or a toroidal continuously variable transmission. The present invention can also be applied to a hybrid vehicle provided with a power split mechanism that combines and splits the power output from the engine and the motor. That is, since the power split mechanism in such a hybrid vehicle functions as a so-called electric continuously variable transmission mechanism, such an electric continuously variable transmission mechanism can also be included in the automatic transmission of the present invention.

  As an example of a vehicle to which the present invention can be applied, FIG. 1 shows the configuration and control system of a vehicle in which an automatic transmission is mounted on the output side of an engine. A vehicle Ve shown in FIG. 1 has a front wheel 1 and a rear wheel 2. In the example shown in FIG. 1, a vehicle Ve is a rear wheel that generates driving force by transmitting power output from an engine (ENG) 3 to a rear wheel 2 via an automatic transmission (AT) 4 and a differential gear 5. It is configured as a driving car. The vehicle Ve to which the present invention can be applied may be a front-wheel drive vehicle that generates power by transmitting the power output from the engine 3 to the front wheels 2. Alternatively, it may be a four-wheel drive vehicle that generates driving force by transmitting power output from the engine 3 to the front wheels 1 and the rear wheels 2, respectively.

  The engine 3 includes, for example, an electronically controlled throttle valve or an electronically controlled fuel injection device, and an airflow sensor that detects the flow rate of intake air. In the example shown in FIG. 1, an electronic throttle valve 6 and an air flow sensor 7 are provided. Therefore, for example, the output of the engine 3 can be automatically controlled by electrically controlling the operation of the electronic throttle valve 6 based on detection data of an accelerator sensor 9 described later.

  An automatic transmission 4 for shifting the output torque of the engine 3 and transmitting it to the drive wheel side is provided on the output side of the engine 3. The automatic transmission 4 is a conventional general stepped automatic transmission composed of, for example, a planetary gear mechanism and a clutch / brake mechanism. By controlling the operation of the clutch mechanism and the brake mechanism, the automatic transmission 4 4 is configured so that the gear position (or gear ratio) set in step 4 can be automatically controlled.

  A controller (ECU) 8 for controlling the output of the engine 3 and the shift operation of the automatic transmission 4 is provided. The controller 8 is an electronic control device mainly composed of a microcomputer, for example. The engine 1 is connected to the controller 8 so that communication for control is possible. The automatic transmission 4 is connected to the controller 8 through a hydraulic control device (not shown) so that communication for control is possible. Although FIG. 1 shows an example in which one controller 8 is provided, a plurality of controllers 8 may be provided for each device or device to be controlled, or for each control content.

  The controller 8 is configured to receive detection signals from various sensors in each part of the vehicle Ve, information signals from various in-vehicle devices, and the like. For example, the air flow sensor 7 described above, the accelerator sensor 9 that detects the accelerator opening, the brake sensor (or brake switch) 10 that detects the amount of depression of the brake pedal, and the engine speed that detects the speed of the output shaft 3a of the engine 3 Detection signals from a sensor 11, an output rotation speed sensor 12 for detecting the rotation speed of the output shaft 4a of the automatic transmission 4, and a vehicle speed sensor 13 for detecting the rotation speeds of the wheels 1 and 2 to obtain the vehicle speed. Is input to the controller 8. And it is comprised so that it may calculate using the input data, the data memorize | stored previously, etc., and a control command signal may be output based on the calculation result.

  In the vehicle Ve configured as described above, as described above, when the vehicle Ve re-accelerates after traveling at a reduced speed, a downshift may be performed when the driver depresses the accelerator pedal. If the downshift performed at the time of deceleration traveling is not appropriate, the driving force is insufficient at the time of reacceleration traveling, and when the reacceleration traveling is started, the gearshift is further lowered (the gear ratio is increased). Become. As a result, the driver may feel uncomfortable or feel that the acceleration feeling is not good. In addition, the driver's intention and driving intention also vary depending on the individual difference of the driver and the driving environment. On the other hand, if the downshift at the time of deceleration traveling as described above is performed uniformly, there is a possibility that the driving force and acceleration intended by the driver cannot be obtained when reacceleration traveling is started.

  Therefore, the controller 8 is configured to appropriately re-accelerate the vehicle Ve by executing the driving force control of the vehicle Ve while reflecting the driver's intention and driving intention in the control. Specifically, the controller 8 obtains the “acceleration during reacceleration” as a control index when the vehicle Ve decelerates and then reaccelerates, and calculates the “reacceleration time” before starting the reacceleration run. The speed ratio of the automatic transmission 4 capable of realizing “acceleration” is set. The “acceleration at the time of reacceleration” serves as a control index at the time of reacceleration running after decelerating, and is an estimate of the acceleration desired by the driver or the acceleration expected by the driver during the reacceleration running. This “acceleration during re-acceleration” is obtained based on acceleration characteristics and travel data of the vehicle Ve. The acceleration characteristic defines the relationship between the “acceleration during reacceleration” and the vehicle speed, and is stored in advance in the form of, for example, an arithmetic expression or a map. The traveling data of the vehicle Ve is a physical quantity representing the traveling state of the vehicle Ve, such as the vehicle speed, acceleration, the gear ratio of the automatic transmission 4, or the engine speed, and is extracted from the traveling history before the current deceleration traveling. The For example, if the controller 8 clears the travel data when the ignition switch (or the main switch) is turned off, the travel history before the current deceleration travel is the last for the current travel. This is a history of travel data acquired from when the ignition switch of the vehicle Ve is turned ON and the control described below in FIG. 2 is first started to the present.

  More specific control contents executed by the controller 8 are shown below. FIG. 2 is a flowchart for explaining an example of basic control. First, it is determined whether or not the acceleration traveling of the vehicle Ve has ended (step S1). For example, it is possible to determine whether or not the acceleration traveling has ended based on the detection value of the vehicle speed sensor 13 or the longitudinal acceleration sensor (not shown). In step S1, it is determined that “the acceleration of the vehicle Ve has ended” when the acceleration of the vehicle Ve becomes zero after it has been determined that the vehicle Ve has been accelerated. Alternatively, this is a case where the vehicle Ve is subsequently decelerated so that the acceleration of the vehicle Ve becomes 0 or less. Or it is when the brake switch 10 is turned on. Accordingly, in all other cases, a negative determination is made in this step S1. For example, after the start of this control, the vehicle Ve has not been accelerated yet, the vehicle Ve is decelerating, the vehicle Ve is accelerated, or the vehicle Ve is steady. If there is, a negative determination is made in step S1.

  If an affirmative determination is made in step S1 because the acceleration traveling of the vehicle Ve has ended, the process proceeds to step S2. In step S2, the expected vehicle speed Vexp and the gradient coefficient K are calculated and updated. Specifically, travel data of the vehicle Ve (for example, vehicle speed at the start of acceleration, maximum acceleration during acceleration travel, etc.) stored during acceleration travel determined to be finished in step S1 is read, and the travel data is stored in the travel data. Based on this, the expected vehicle speed Vexp and the gradient coefficient K are updated. When the driver operates the vehicle Ve, it can be assumed that the driver is always driving aiming at a predetermined vehicle speed. In the control by the controller 8, the vehicle speed targeted by the driver as described above or the vehicle speed estimated to be desired by the driver is defined as "expected vehicle speed". Generally, under the same driving environment, the “expected vehicle speed” increases when the driver's driving orientation becomes a driving orientation (sport driving orientation) that emphasizes power performance and exercise performance more than usual. On the other hand, if the driver's driving orientation is a driving orientation that emphasizes fuel efficiency and efficiency more than usual (fuel consumption driving orientation), the “expected vehicle speed” decreases. The expected vehicle speed Vexp can be obtained based on the travel history of the vehicle Ve in which data such as the vehicle speed, longitudinal acceleration, lateral acceleration, steering angle, road surface gradient, and vehicle attitude are recorded. As will be described later, the slope coefficient K represents the slope of the correlation line used when obtaining the “expected vehicle speed”. Details of the expected vehicle speed Vexp and the gradient coefficient K will be described later.

  On the other hand, if a negative determination is made in step S1, the process proceeds to step S3. In step S3, the previous values of the expected vehicle speed Vexp and the gradient coefficient K are held. That is, the expected vehicle speed Vexp and the gradient coefficient K that are calculated and stored when the previous acceleration travel ends are held until the current acceleration travel ends. Note that if acceleration traveling has not yet been performed since the start of this control, for example, the expected vehicle speed Vexp and the gradient coefficient K stored when the ignition switch is turned on and this control is first started are stored. Will continue to be retained. In the configuration in which the expected vehicle speed Vexp and the gradient coefficient K are cleared when the ignition switch is turned OFF, the preset initial values are read when the ignition switch is turned ON, and the expected vehicle speed Vexp and the gradient coefficient are read. Stored as K. Therefore, when acceleration traveling has not yet been performed since the start of this control as described above, the initial values of the expected vehicle speed Vexp and the gradient coefficient K are held. In the configuration in which the expected vehicle speed Vexp and the gradient coefficient K at that time are stored when the ignition switch is turned OFF, as described above, when acceleration traveling has not yet been performed, The expected vehicle speed Vexp and the gradient coefficient K stored when the ignition switch is turned off are read and held continuously.

  When the expected vehicle speed Vexp and the gradient coefficient K are updated in the above step S2, or when the previous values of the expected vehicle speed Vexp and the gradient coefficient K are held in the above step S3, the process proceeds to step S4. In step S4, a reacceleration acceleration Gexp is obtained. When the vehicle Ve decelerates without stopping, the vehicle Ve shifts to a state where the vehicle Ve re-accelerates after finishing the decelerating travel. For example, when the vehicle Ve turns in a corner, the vehicle Ve generally enters the corner while decelerating from the front of the corner. In corners, decelerate or turn at a constant speed. And, when escaping from the corner, it re-accelerates. Thus, when the vehicle Ve travels again after decelerating, it can be assumed that the driver accelerates the vehicle Ve toward the expected vehicle speed Vexp. Therefore, if the vehicle speed difference ΔV (ΔV = Vexp−Vcur) between the expected vehicle speed Vexp and the current vehicle speed Vcur is large, the driver requests a large acceleration to reduce the vehicle speed difference ΔV and re-accelerates the vehicle Ve. I can guess it.

Based on the above assumption, in this step S4, the acceleration Gexp at the time of reacceleration is obtained as the acceleration expected by the driver during the reacceleration running from the vehicle speed difference ΔV between the expected vehicle speed Vexp and the current vehicle speed Vcur. For example, as shown in FIGS. 3 and 4, it is known from the results of running experiments and simulations that there is a negative correlation between the “acceleration during reacceleration” and the vehicle speed. When the vehicle speed at the time of starting the reacceleration running is the x axis and the acceleration (maximum ground acceleration) at that time is the y axis, a linear function correlation line (approximate as shown by “y = a · x + b” in FIG. 4) Line). This correlation line can also be obtained for each driver's driving orientation, as indicated by broken lines f ₁ , f ₂ , and f ₃ in FIG.

  As described above, the “expected vehicle speed” is defined as the vehicle speed targeted by the driver during acceleration traveling. Therefore, when the vehicle speed reaches this “expected vehicle speed”, it is unnecessary to further accelerate the vehicle Ve, and as a result, it can be estimated that the acceleration becomes zero. Accordingly, the “expected vehicle speed” can be obtained by calculating the x intercept (−a / b) at which the y-axis acceleration becomes zero in the linear function correlation line as shown in FIG.

  In addition, said ground acceleration is an acceleration which can be calculated | required as a differential value of the detection data of the output rotation speed sensor 12 or the vehicle speed sensor 13, for example. Although the acceleration can be obtained by an acceleration sensor mounted on the vehicle Ve, in that case, noise may be included in the acceleration detection data due to the influence of the attitude of the vehicle Ve or the road surface gradient. Therefore, in this control, the ground acceleration obtained from the rotation speed sensor as described above is used.

  Using the correlation between the “acceleration at the time of reacceleration” and the vehicle speed as described above, the relationship between the “acceleration at the time of reacceleration” and the vehicle speed is determined in advance as the acceleration characteristic of the vehicle Ve and stored in the controller 8. I can leave. By determining such acceleration characteristics as a function of vehicle speed, it is possible to calculate “acceleration during reacceleration” corresponding to the “expected vehicle speed” and “current vehicle speed” as described above.

  Further, “acceleration during reacceleration” corresponding to “expected vehicle speed” and “current vehicle speed” can be obtained from a control map as shown in FIG. 5, for example. That is, using the correlation between the “acceleration at the time of reacceleration” and the vehicle speed obtained from the travel history or travel information at the time of previous acceleration travel, the relationship between the “acceleration at the time of reacceleration” and the vehicle speed in advance. The acceleration characteristic of the vehicle Ve can be determined and stored in the controller 8 as a control map as shown in FIG.

  In FIG. 5, the straight line f corresponds to the above-mentioned correlation line “y = a · x + b”, and shows an acceleration characteristic that defines the relationship between “acceleration during reacceleration” and the vehicle speed. The slope of this straight line f indicates the slope coefficient K. On the straight line f, the vehicle speed at which the ground acceleration becomes 0, that is, the x intercept of the straight line f is the “expected vehicle speed”. Therefore, in FIG. 5, by applying the current vehicle speed Vcur to the straight line f passing through the expected vehicle speed Vexp obtained in step S2 described above and the relational expression indicated by the straight line f and the gradient coefficient K, the acceleration Gexp at the time of re-acceleration Can be requested.

  Further, a plurality of straight lines f can be set for each “expected vehicle speed” as described above or according to driving orientation, as indicated by the straight lines fs and fm in FIG. 5, for example. In that case, a predetermined straight line f is determined from among a plurality of correlation lines as the correlation line based on the travel history during the previous acceleration travel. At the same time, an “expected vehicle speed” is obtained as the x intercept of the straight line f. In this way, the “expected vehicle speed” obtained based on the history during the previous acceleration travel reflects the driving orientation that appeared during the previous acceleration travel. Then, “acceleration at re-acceleration” is obtained based on “expected vehicle speed” obtained as described above and “current vehicle speed” obtained as a detection value of the vehicle speed sensor 13, for example. As shown in FIG. 5, the “acceleration during reacceleration” increases as the difference between the “expected vehicle speed” and the “current vehicle speed” increases. In addition, as the driving orientation is stronger, the straight line fs having the larger “expected vehicle speed” is selected, and the “acceleration at the time of reacceleration” obtained thereby increases. On the contrary, as the driving orientation is more fuel-efficient, the straight line fm having a smaller “expected vehicle speed” is selected, and the “acceleration at the time of reacceleration” obtained thereby becomes smaller.

As described above, when the reacceleration acceleration Gexp is obtained in step S4, the gear position of the automatic transmission 4 capable of realizing the reacceleration acceleration Gexp is obtained (step S5). In other words, an optimum gear stage set by the automatic transmission 4 is required in order for the vehicle Ve to accelerate with the acceleration Gexp during reacceleration. An example of a method for obtaining such a shift stage is shown in FIG. First, outputable acceleration Gabl is set. The output possible acceleration Gabl is expressed as follows: Te _{max is} the maximum output torque of the engine 3, R is the running resistance, W is the vehicle weight, and g is the gear ratio.
Gabl = (Te _max · g−R) / W
It can be calculated from the following formula. As shown in FIG. 6, the outputable acceleration Gabl is calculated for each gear position of the automatic transmission 4.

  FIG. 6 shows an example in which the automatic transmission 4 is an 8-speed stepped transmission. In the example shown in FIG. 6, with respect to the “acceleration at the time of reacceleration” obtained from the “expected vehicle speed” and the “current vehicle speed”, a gear stage that can achieve the “acceleration at the time of reacceleration” (this figure In the example 6, the fastest stage (second speed in the example of FIG. 6) among the second speed, the third speed, the fourth speed, and the fifth speed is selected. That is, in FIG. 6, the acceleration Gexp at the time of reacceleration is represented as an intersection of a correlation line passing through the expected vehicle speed Vexp and a straight line indicating the current vehicle speed Vcur. The point indicating the acceleration Gexp at the time of re-acceleration is located between the fifth speed outputable acceleration Gabl and the sixth speed outputable acceleration Gabl. This is because, when the engine 3 outputs the maximum torque, if the automatic transmission 4 is set to the sixth speed or higher speed stage (6th speed, 7th speed, 8th speed), the acceleration at the time of reacceleration This means that Gexp cannot be achieved. Therefore, in the example shown in FIG. 6, the fifth highest speed stage among the fifth speed and lower speed stages (from the fifth speed to the first speed) of the automatic transmission 4 that can achieve the acceleration Gexp at the time of reacceleration. Speed is selected.

  When the gear position (speed ratio) of the automatic transmission 4 capable of realizing the reacceleration acceleration Gexp is calculated in step S5, it is determined whether or not the vehicle Ve is traveling at a reduced speed (step S6). For example, it can be determined whether or not the vehicle Ve is traveling at a reduced speed based on the detection value of the vehicle speed sensor 13 or the longitudinal acceleration sensor (not shown), the operation signal of the brake switch 10, and the like. If the vehicle Ve is not traveling at a reduced speed, and if a negative determination is made in step S6, the routine is temporarily terminated without executing the subsequent control.

  On the other hand, when the vehicle Ve is traveling at a reduced speed, if the determination in step S6 is affirmative, the process proceeds to step S7. In step S7, whether or not the gear stage currently set in the automatic transmission 4 is higher than the gear stage calculated in step S5, that is, the gear ratio of the current gear stage is calculated. It is determined whether or not the transmission gear ratio is smaller than the transmission gear ratio. If the current shift speed is lower than the calculated shift speed, and if a negative determination is made in step S7, this routine is temporarily terminated without executing the subsequent control.

  On the other hand, if the current shift speed is higher than the calculated shift speed, and if the determination in step S7 is affirmative, the process proceeds to step S8, and the automatic shift toward the calculated shift speed is performed. A downshift is performed by the transmission 4. Thereafter, this routine is once terminated.

  A specific configuration of the controller 8 that executes the control during deceleration traveling as described above is shown in the block diagram of FIG. As an example, the controller 8 includes an acceleration calculation unit B1, an expected vehicle speed calculation unit B2, a reacceleration acceleration calculation unit B3, an outputable acceleration calculation unit B4, a target shift speed calculation unit B5, and a shift output determination unit B6. Has been.

  The acceleration calculation unit B1 calculates the acceleration of the vehicle Ve based on the detection data of the output rotation speed sensor 12. The acceleration of the vehicle Ve can also be calculated from the detection data of the vehicle speed sensor 13. The expected vehicle speed calculation unit B2 calculates the expected vehicle speed Vexp based on the acceleration data calculated by the acceleration calculation unit B1 and the detection data of the vehicle speed sensor 13. The reacceleration acceleration calculation unit B3 calculates the reacceleration acceleration Gexp based on the vehicle speed difference ΔV between the expected vehicle speed Vexp calculated by the expected vehicle speed calculation unit B2 and the current vehicle speed Vcur obtained from the detection data of the vehicle speed sensor 13. To do. On the other hand, the outputable acceleration calculating unit B4 calculates the outputable acceleration Gabl for each gear position (or gear ratio) of the automatic transmission 4 based on the detection data of the airflow sensor 7. The target shift speed calculation unit B5 is a target for the automatic transmission 4 based on the reacceleration acceleration Gexp calculated by the reacceleration acceleration calculation unit B3 and the outputable acceleration Gabl calculated by the outputable acceleration calculation unit B4. A gear position (or target gear ratio) is calculated. Then, the shift output determination unit B6 determines the shift command for the automatic transmission 4 based on the target shift stage calculated by the target shift stage calculation unit B5, the detection data of the accelerator sensor 9, and the detection data of the brake switch 10. I do. Specifically, it is determined whether or not it is necessary to perform a downshift on the automatic transmission 4.

  FIG. 6 shows an example in which the automatic transmission 4 is an 8-speed stepped transmission. However, the automatic transmission 4 of the present invention may be a belt-type or toroidal-type continuously variable transmission, or a hybrid. An electric continuously variable transmission mechanism in a vehicle can also be targeted. When the automatic transmission 4 is a continuously variable transmission or an electric continuously variable transmission mechanism of a hybrid vehicle as described above, the gear ratio of the automatic transmission 4 that can realize “acceleration at reacceleration” is calculated, The automatic transmission 4 is controlled based on the calculated gear ratio. For example, as shown in FIG. 8A, a gear ratio γ capable of realizing “acceleration during re-acceleration” is obtained from “current vehicle speed” and “expected vehicle speed”, and an automatic transmission is based on the gear ratio γ. 4 is controlled. FIG. 8B shows the behavior of the engine speed in that case.

  In the embodiment described above, the “expected vehicle speed” is obtained from, for example, the correlation line as shown in FIG. 4 or the control map as shown in FIG. The correlation lines shown in FIG. 4 and the control map shown in FIG. 5 are set on the basis of travel data during past acceleration travel. If past driving data used in that case is simply accumulated, the amount of data becomes enormous. In addition, if past driving data is excessively emphasized, even if the driving environment or driving orientation changes, the driving data before the change will be applied. The estimation accuracy of “acceleration” may decrease. Therefore, in the driving force control by the controller 8, weighting is performed on the travel data used for obtaining the “expected vehicle speed”.

  The weighting of the travel data as described above is performed by multiplying the past travel data by a predetermined weight coefficient. Alternatively, it is carried out by selecting predetermined traveling data from the history of all traveling data and using it for calculating the “expected vehicle speed”. For example, the running data can be weighted by multiplying the past running data used for setting the correlation line shown in FIG. 4 or the control map shown in FIG. 5 by a weighting coefficient w (w <1). it can. Alternatively, the running data can be weighted by setting the correlation line shown in FIG. 4 using only the latest running data that has been traced a predetermined number of times from the latest.

For example, as shown in the graph of FIG. 9, data obtained by plotting predetermined traveling data on the graph is a point (x ₀ , y ₀ ), and an approximate line obtained from the history of traveling data is “y = a · x + b”. Then, the error d of the point (x ₀ , y ₀ ) is
d = (y ₀ −a · x ₀ −b)
It becomes. The square error (w) · d ² considering the weighting factor w for weighting is
(W) · d ² = (w) · (y ₀ -a · x ₀ -b) ²
It becomes. Therefore, by calculating the coefficient a and the coefficient b that minimize the square error (w) · d ² , the approximate line “y = a · x + b” can be obtained. The coefficient a and the coefficient b that minimize the square error (w) · d ² are calculated by the recurrence formulas represented by the following formulas (1) and (2), respectively.

In the above (1) and (2) below, when the term of the sum of ^{x 2} and _{A n, A n-1} and _{A n,} respectively, as follows: (3) and (4) It is expressed by a recurrence formula.

Respect term of (1) and (2) the sum of ^{x 2} in the recurrence formula of Formula, the previous value of the sum _{(A n-1)} the current value of ^{x 2} and _(x ^{n 2)} was added, the sum thereof The current value (A _n ) of the sum can be obtained by multiplying by a weight coefficient w. This also applies to the other summation terms in the recurrence formulas of the above equations (1) and (2). Therefore, for the coefficients a and b represented by the above equations (1) and (2), the current value can be obtained if the previous value of the sum is known. Therefore, even if not all past travel data histories are stored, if the previous value of the sum is stored, the approximate line “y = weighted by the weighting coefficient w from the previous value and the current value of the sum is stored. a · x + b ”can be obtained.

  When the weighting coefficient w as described above is set to, for example, “w = 0.7” and the weighting of the running data is performed, as shown in FIG. Will be occupied. Thus, by performing weighting as described above, it is possible to increase the importance of the most recent data, for example, it is possible to clear past data that has become less important. Also, by making the weighting factor w constant, the change in each recurrence formula as described above becomes constant, and as a result, the approximate line “y = a · x + b "can be easily obtained. Therefore, weighting the driving data as described above ensures a certain estimation accuracy of the “expected vehicle speed” and “acceleration at the time of reacceleration”, and the load of the memory for storing the data and the calculation process. Can reduce the load.

  As described above, in the driving force control by the controller 8, when the reacceleration travel after the deceleration travel is performed, the speed ratio that enables the acceleration travel with the “acceleration during reacceleration” is set before the reacceleration travel is started. Thus, the shift control of the automatic transmission 4 can be completed. In addition, by obtaining the “acceleration at the time of reacceleration” based on the “expected vehicle speed” as described above, the “acceleration at the time of reacceleration” is determined as a control index for shift control that reflects the driver's intention and driving orientation. can do. Therefore, at the start of reacceleration running after deceleration running, the automatic transmission 4 can set a gear ratio capable of obtaining a driving force necessary for reacceleration in advance. Further, the gear ratio set at that time is a gear ratio that is estimated to be able to accelerate the vehicle at an acceleration intended by the driver or an acceleration requested by the driver.

  For example, when the vehicle Ve turns in a corner, the vehicle Ve re-accelerates in the exit stage from the corner in advance during the deceleration travel of the vehicle Ve from the corner entry stage to the corner turning stage. The automatic transmission 4 can be downshifted to a gear ratio that is suitable at times, that is, a gear ratio that can realize “acceleration during reacceleration”. Therefore, when the vehicle Ve enters the corner and makes a turn, the vehicle Ve can be appropriately decelerated and a stable turn can be performed while maintaining a state where a large driving force can be obtained. When the vehicle Ve escapes from the corner and starts reacceleration running, the downshift has already been completed to a state where sufficient driving force can be obtained as described above.

  Therefore, according to the driving force control by the controller 8, since the downshift at the time of the deceleration traveling is insufficient, the downshift is further performed to compensate for the lack of the driving force at the time of the reacceleration traveling after the deceleration traveling. By avoiding this, the vehicle can be appropriately accelerated. Therefore, it is possible to suppress the driver from feeling uncomfortable or shock, and to improve the acceleration performance and acceleration feeling of the vehicle Ve.

  Further, in the driving force control by the controller 8, the “expected vehicle speed” is updated every time acceleration traveling is performed. By updating the “expected vehicle speed” in this way, the latest driving orientation of the driver can be reflected in the control. For example, when the driver's driving orientation changes from fuel-efficient driving orientation to sports driving orientation, the “expected vehicle speed” is updated to an increasing side, and as a result, the automatic transmission 4 has a large shift on the lower speed side. The ratio is easily set. Therefore, in the subsequent reacceleration running, a larger driving force can be generated to enable a strong acceleration running, and the vehicle Ve is appropriately reflected by reflecting the change in the driving orientation to the sports driving orientation as described above. Can be accelerated.

  By the way, if the “expected vehicle speed” is updated only during acceleration traveling as described above, in most cases, it is updated to an increasing side (that is, a sport driving-oriented side) and decreased (that is, a fuel consumption traveling). It will almost never be updated. Therefore, for example, when the driver's driving orientation is reduced from a sport driving orientation to a normal driving orientation, or when the driver's driving orientation is reduced from a normal driving orientation to a fuel consumption driving orientation, the driver is required to perform the subsequent reacceleration driving. There is a possibility that a larger gear ratio on the lower speed side than intended is set.

  Therefore, the controller 8 sets an appropriate “expected vehicle speed” even when the driving orientation is reduced to the fuel consumption driving-oriented side, and an appropriate driving force that accurately reflects the driver's intention and driving orientation. It is comprised so that control can be performed.

  An example of the control for dealing with the case where the driving orientation is reduced as described above is shown in FIG. In the control shown in the flowchart of FIG. 11, it is first determined whether or not the driver's driving orientation is in a decreasing state (step S101). Specifically, it is determined whether or not the currently set expected vehicle speed Vexp is being reduced. For example, when the vehicle Ve is traveling slowly decelerating, it is determined that the vehicle is in a state of reducing the expected vehicle speed Vexp. Alternatively, when the vehicle Ve is traveling steadily, it is determined that the expected vehicle speed Vexp is being reduced.

  The slow deceleration traveling is a traveling state in which, for example, the vehicle Ve slowly decelerates when coasting. In this control, the vehicle Ve decelerates at a deceleration within a deceleration range (determination region) lower than a predetermined deceleration, or a determination region closer to 0 than the predetermined deceleration on the negative acceleration side. The traveling state in which the vehicle decelerates at the deceleration is defined as slow deceleration traveling. This slow deceleration traveling is defined in order to distinguish from the state where the vehicle Ve travels at a reduced speed by a braking operation based on the clear intention of the driver. For example, when the vehicle Ve continues to decelerate at a deceleration within a deceleration range (determination area) lower than a predetermined deceleration as described above, or when the vehicle is When the state where the vehicle is decelerated at a deceleration in the determination region closer to 0 than the predetermined deceleration on the negative acceleration side continues for a predetermined time or more, it is determined that the traveling state of the vehicle Ve is the slow deceleration traveling. . In this control, the deceleration is a negative acceleration. Accordingly, the deceleration can be obtained, for example, as a differential value of detection data of the output speed sensor 12 or the vehicle speed sensor 13 or as a detection value of the longitudinal acceleration sensor, similarly to the acceleration described above.

  In addition, steady running is a running state in which almost no acceleration occurs. In this control, the vehicle Ve travels at a substantially constant speed within a predetermined acceleration range including zero, or the vehicle Ve is constant at an acceleration within a predetermined acceleration range including acceleration greater than zero and acceleration smaller than zero. A traveling state in which the vehicle travels at a high speed or a substantially constant speed is defined as steady traveling. For example, when the vehicle Ve travels at a substantially constant speed within a predetermined acceleration range including 0 as described above for a predetermined time or more, or when the vehicle Ve has an acceleration greater than 0 and 0 When the vehicle travels at a constant speed or at a substantially constant speed within a predetermined acceleration range including a smaller acceleration for a predetermined time or more, the vehicle Ve is determined to be in a steady state.

  Therefore, for example, when the running state of the vehicle Ve is neither the slow deceleration running nor the steady running as described above, it is determined that the expected vehicle speed Vexp is not lowered. On the other hand, when the traveling state of the vehicle Ve is one of the slow deceleration traveling and the steady traveling as described above, it is determined that the expected vehicle speed Vexp is reduced.

  If it is determined in step S101 that the expected vehicle speed Vexp has been reduced, the process proceeds to step S102. In step S102, a provisional line for reducing the expected vehicle speed Vexp is set. Specifically, with respect to the acceleration history line that has been calculated using the history of travel data from the past (that is, the above-mentioned correlation line), the provisional provision is made that the acceleration and the vehicle speed are both lower than the acceleration history line. A line is set.

  For example, the provisional line can be set as a straight line having the same inclination (that is, the above-described gradient coefficient K) as the acceleration history line and a predetermined distance D away from the acceleration history line. The region below the acceleration history line is, for example, a region where both acceleration and vehicle speed are smaller than the acceleration history line on a graph as shown in FIG. The predetermined distance D is set in advance, for example, for a case where the driving orientation is reduced from a sports driving orientation to a normal driving orientation and a case where the driving orientation is reduced from a normal driving orientation to a fuel consumption driving orientation.

  In addition, the provisional line can be set as a straight line including at least two times of travel data within the latest period, which is a period that is a predetermined number of times from the latest. For example, on the graph of FIG. 12 or FIG. 13, traveling data at the time of two accelerated travelings in the latest period can be plotted, and a provisional line can be obtained as a straight line passing through the two plotted points.

  In addition, the provisional line can be set as a straight line that includes one run data in the most recent period and has the same inclination as the acceleration history line. For example, on the graph of FIG. 12 or FIG. 13, travel data at the time of two acceleration travels in the most recent period is plotted, and the provisional line as a straight line passing through the plotted points and having the same slope as the acceleration history line. Can be requested.

  In step S102, the provisional line is set as described above, and the conventional acceleration history line is held. That is, the conventional acceleration history line is continuously stored without being cleared.

  When the provisional line is set in step S102, the process proceeds to step S103. On the other hand, if it is determined that the expected vehicle speed Vexp is not in a state of being lowered, and the determination is negative in step S101, the process skips step S102 and proceeds to step S103. In step S103, it is determined whether or not the acceleration traveling of the vehicle Ve has ended. This is the same control content as step S1 in the flowchart of FIG.

  If an affirmative determination is made in step S103 due to the end of the accelerated traveling of the vehicle Ve, the process proceeds to step S104. In step S104, the acceleration history line is updated. Specifically, the latest acceleration history line is calculated by reflecting the travel data acquired during the latest acceleration travel. Then, the acceleration history line held in step S102 is updated to the latest acceleration history line obtained here.

  On the other hand, the acceleration traveling of the vehicle Ve has not yet ended, the acceleration traveling has not yet been performed after the start of this control, the vehicle Ve is in acceleration traveling, or the vehicle Ve is in steady traveling. If there is a negative determination in step S103, the process proceeds to step S105. In step S105, the acceleration history line is maintained. That is, in step S105, the acceleration history line maintained in step S102 is continuously maintained without updating the acceleration history line as in step S104.

  If the acceleration history line is updated in step S104, or if the previous acceleration history line is maintained in step S105, the process proceeds to step S106. In step S106, it is determined whether to use a provisional line. Specifically, the estimation accuracy of the provisional line set as described above is verified, and based on the verification result, whether or not the above-described provisional line should be used to calculate the acceleration Gexp during re-acceleration. To be judged.

  In this step S106, for example, when the point where the latest traveling data is plotted on the graph shown in FIG. 12 is located in an area above the last updated acceleration history line, a temporary line is used. Judged not to be. The region above the acceleration history line is a region on the graph shown in FIG. 12 where both acceleration and vehicle speed are larger than the acceleration history line. In this way, when the latest travel data is larger than the acceleration history line, the provisional line in which the acceleration and the vehicle speed are both reduced in a direction that makes the acceleration history line smaller than the acceleration history line appropriately reflects the driver's driving orientation. It can be estimated that they have not. That is, in this case, although the provisional line is lowered from the acceleration history line in step S102, it is considered that the actual driving orientation has not been lowered. Therefore, when the latest traveling data is larger than the acceleration history line as described above, it is determined that the provisional line should not be used.

  Further, in this step S106, for example, on the graph as shown in FIG. 13, even if the point where the latest traveling data is plotted is located in a region below the last updated acceleration history line, If the point is sufficiently close to the acceleration history line, it is determined that the provisional line should not be used. When the latest travel data is sufficiently close to the acceleration history line, for example, the latest travel data is within a predetermined range between the acceleration history line and a straight line separated by a distance d below the acceleration history line. This is the case where the point where is plotted is located. Thus, when the latest travel data is sufficiently close to the acceleration history line, it can be estimated that the acceleration history line appropriately reflects the driver's driving orientation rather than the provisional line. Therefore, when the latest travel data is sufficiently close to the acceleration history line as described above, it is determined that the provisional line should not be used.

  If it is determined that the provisional line should not be used and thus a negative determination is made in step S106, the process proceeds to step S107. In step S107, the acceleration Gexp during reacceleration is calculated using the latest acceleration history line updated in step S104 or the previous acceleration history line maintained in step S105. In this case, the provisional line that no longer contributes to the calculation of the acceleration Gexp during reacceleration may be cleared. By doing so, it is possible to reduce the load on the memory for storing the provisional line and the data related thereto and the load on the arithmetic processing.

  On the other hand, if it is determined affirmative in step S106 because it is determined that the provisional line should be used, the process proceeds to step S108. In step S108, the acceleration Gexp during re-acceleration is calculated using the provisional line set in step S102. The re-acceleration acceleration Gexp in steps S107 and S108 is obtained by the same method as in step S4 in the flowchart of FIG.

  As described above, when the reacceleration acceleration Gexp is obtained in step S107 or step S108, the gear position of the automatic transmission 4 capable of realizing the reacceleration acceleration Gexp is obtained (step S109). In other words, an optimum gear stage set by the automatic transmission 4 is required in order for the vehicle Ve to accelerate with the acceleration Gexp during reacceleration. This is the same control content as step S5 in the flowchart of FIG.

  When the gear position (gear ratio 8) of the automatic transmission 4 capable of realizing the reacceleration acceleration Gexp is calculated in step S109, it is determined whether or not the vehicle Ve is traveling at a reduced speed (step S110). If the vehicle Ve is not decelerating and the determination is negative in this step S110, this routine is temporarily terminated without executing the subsequent control.

  On the other hand, when the vehicle Ve is traveling at a reduced speed, if the determination in step S110 is affirmative, the process proceeds to step S111. In step S111, it is calculated whether or not the speed currently set in the automatic transmission 4 is higher than the speed calculated in step S109, that is, the speed ratio of the current speed is calculated. It is determined whether or not the transmission gear ratio is smaller than the transmission gear ratio. If the current shift speed is lower than the calculated shift speed, and if a negative determination is made in step S111, this routine is temporarily terminated without executing the subsequent control.

  On the other hand, if the current shift speed is higher than the calculated shift speed, and if an affirmative determination is made in step S111, the process proceeds to step S112, and the automatic transmission is directed toward the calculated shift speed. A downshift is performed at 4. Steps S110, S111, and S112 are the same control contents as steps S6, S7, and S8 in the flowchart of FIG. When downshifting is performed in step S112, this routine is once terminated.

  Thus, in the control shown in the flowchart of FIG. 11, for example, when it is estimated that the driver's driving orientation has decreased to the fuel consumption traveling-oriented side due to, for example, the vehicle Ve traveling slowly and decelerating, the acceleration history The line and the latest driving data are compared. In other words, the provisional line estimation accuracy is verified. When the vehicle speed and acceleration in the latest travel data are both greater than the acceleration history line, or when the vehicle speed and acceleration in the latest travel data are both within the specified range near the acceleration history line Is determined that the estimation accuracy of the provisional line is not good. Therefore, the expected vehicle speed is obtained using the acceleration history line without using the provisional line. On the other hand, if the vehicle speed and acceleration in the latest travel data are values that are not included in the predetermined range near the acceleration history line and are smaller than the acceleration history line, the provisional line estimation accuracy is Is judged good. Therefore, the expected vehicle speed Vexp is obtained using the provisional line.

  Therefore, according to the control shown in the flowchart of FIG. 11, when the driver's driving orientation changes to the fuel consumption driving orientation side, the expected vehicle speed Vexp can be set corresponding to the driving orientation change. At the same time, an appropriate expected vehicle speed Vexp can be set according to the estimation accuracy of the change in driving orientation, that is, the estimation accuracy of the provisional line. As a result, the driving force of the vehicle Ve can be controlled by appropriately reflecting the driver's intention and driving intention.

In the control example shown in the flowchart of FIG. 11 above, the estimation accuracy of the provisional line is verified,
Based on the verification result, it is determined whether to use a provisional line. On the other hand, in the driving force control by the controller 8, as shown in the flowchart of FIG. 14, it is possible to control the temporary line so as to be corrected based on the verification result of the estimated accuracy of the temporary line. In the control example shown in the flowchart of FIG. 14, steps S201 to S207 are the same control contents as steps S101 to S107 in the flowchart of FIG.

  That is, as in step S106 in the flowchart of FIG. 11, it is determined in step S206 in the flowchart of FIG. 14 whether or not a provisional line is used. Specifically, the estimation accuracy of the provisional line set as described above is verified, and based on the verification result, whether or not the above-described provisional line should be used to calculate the acceleration Gexp during re-acceleration. To be judged.

  If it is determined that the provisional line should not be used and thus a negative determination is made in step S206, the process proceeds to step S207. In step S207, the acceleration Gexp during re-acceleration is calculated using the acceleration history line. In this case, the provisional line that no longer contributes to the calculation of the acceleration Gexp during reacceleration may be cleared. By doing so, it is possible to reduce the load on the memory for storing the provisional line and the data related thereto and the load on the arithmetic processing.

  On the other hand, if it is determined in step S206 that the provisional line should be used, the process proceeds to step S208. In step S208, the provisional line is corrected based on the latest travel data. Specifically, the temporary line is corrected so that the divergence between the temporary line and the latest travel data is reduced by bringing the temporary line set in step S202 closer to the latest travel data.

  For example, as shown in FIG. 16, when the point where the latest travel data is plotted on the graph of FIG. 16 is located in a region above the provisional line set in step S202, the provisional line is the latest. It is raised in the direction approaching the driving data. For example, the provisional line set in step S202 is translated by a predetermined distance in a direction approaching the latest travel data, and the corrected provisional line is set. The predetermined distance in this case is set in advance according to the vehicle speed and acceleration of the acquired travel data. Alternatively, the provisional line set in step S202 is translated to a straight line including the latest travel data, and the corrected provisional line is set.

  In addition, as shown in FIG. 16, when the point where the latest travel data is plotted on the graph of FIG. 16 is located in an area below the provisional line set in step S202, the provisional line is the latest. It is lowered in a direction approaching the running data. For example, the provisional line set in step S202 is translated by a predetermined distance in the direction approaching the latest travel data, and the corrected provisional line is set. The predetermined distance in this case is also set in advance according to the vehicle speed and acceleration of the acquired travel data. Alternatively, the provisional line set in step S202 is translated to a straight line including the latest travel data, and the corrected provisional line is set.

  When the provisional line is corrected in step S208, the reacceleration acceleration Gexp is calculated using the corrected provisional line (step S209). This is the same control content as step S4 in the flowchart of FIG. 2 and step S108 in the flowchart of FIG.

  As described above, when the reacceleration acceleration Gexp is obtained in step S207 or step S209, the gear position of the automatic transmission 4 capable of realizing the reacceleration acceleration Gexp is obtained (step S210). In other words, an optimum gear stage set by the automatic transmission 4 is required in order for the vehicle Ve to accelerate with the acceleration Gexp during reacceleration. Steps S210 to S213 after step S210 are the same control contents as steps S109 to S112 in the flowchart of FIG.

  Thus, in the control shown in the flowchart of FIG. 14, the vehicle speed and acceleration in the latest travel data are values that are not included in the predetermined range near the acceleration history line, and are smaller than the acceleration history line. Thus, when it is determined that the estimation accuracy of the temporary line is good, the expected vehicle speed Vexp is obtained using the corrected temporary line. That is, the estimation accuracy of the provisional line is good, and when it is determined that the expected vehicle speed Vexp should be set using the provisional line, the provisional line is corrected based on the latest travel data, and the correction further increases the accuracy. The expected vehicle speed Vexp is obtained using a provisional line with an increased. Therefore, the intention and driving orientation of the driver can be reflected in the control with higher accuracy.

  In the specific example described above, the “acceleration history line” and the “provisional line” are both straight lines, but the “acceleration history line” and the “provisional line” are curves. Also good. For example, the “acceleration history line” can be obtained as an approximate curve of past travel data. Then, for example, the “provisional line” can be obtained as a curve obtained by translating the “acceleration history line” by a predetermined distance in the same line as the “acceleration history line” obtained as a curve as described above.

  Furthermore, in the specific example described above, both the “acceleration history line” and the “provisional line” are described as diagrams shown on the graph, but these “acceleration history line” and “provisional line”, In addition, a correlation line (straight line f) between the vehicle speed and the acceleration can be used in the form of a function, an equation, or a correlation expression representing a diagram.

  DESCRIPTION OF SYMBOLS 1 ... Front wheel, 2 ... Rear wheel (drive wheel), 3 ... Engine, 4 ... Automatic transmission, 6 ... Electronic throttle valve, 7 ... Air flow sensor, 8 ... Controller (ECU), 9 ... Accelerator sensor, 10 ... Brake sensor (Brake switch), 11 ... engine speed sensor, 12 ... output speed sensor, 13 ... vehicle speed sensor, Ve ... vehicle.

Claims (6)

In a driving force control device that controls the driving force of a vehicle including an engine, driving wheels, and an automatic transmission that transmits torque between the engine and the driving wheels based on a vehicle speed and an accelerator opening,
A controller for controlling the driving force;
The controller is
An acceleration history line is calculated using a correlation of travel data storing vehicle speed and acceleration of the vehicle at the time of acceleration traveling before the vehicle decelerates, and the acceleration history line is calculated each time the acceleration traveling is performed. Updated,
When the vehicle decelerates at a deceleration within a deceleration range that is closer to 0 than a predetermined deceleration on the negative acceleration side, or the vehicle has an acceleration within a predetermined acceleration range that includes positive acceleration and negative acceleration. When running at a constant speed, set a provisional line in which both the vehicle speed and the acceleration are smaller than the acceleration history line,
Expected to be desired by the driver when the vehicle reaccelerates based on the acceleration history line or the provisional line as the target vehicle speed when the vehicle reaccelerates after the vehicle decelerates Set the vehicle speed,
Based on the current vehicle speed and the expected vehicle speed, a reacceleration acceleration is obtained as a control index when the vehicle reaccelerates,
Before the vehicle starts the reacceleration running, it is configured to set a gear ratio of the automatic transmission capable of realizing the reacceleration acceleration based on the reacceleration acceleration,
The expected vehicle speed is
When the vehicle speed and the acceleration in the latest travel data are larger than the latest acceleration history line, or when the values are included in a predetermined range close to the latest acceleration history line, the acceleration history line Set based on
The vehicle speed and the acceleration in the latest traveling data are set based on the provisional line when the vehicle speed and the acceleration are smaller than the latest acceleration history line and are not included in the predetermined range. A driving force control device.
The driving force control apparatus according to claim 1,
The controller is
The driving force control device, wherein the provisional line is cleared when the expected vehicle speed is set based on the acceleration history line.
In the driving force control device according to claim 1 or 2,
The controller is
The driving force control apparatus characterized in that the provisional line is set by lowering the acceleration history line by a predetermined distance in a direction in which both the vehicle speed and the acceleration become smaller than the acceleration history line.
In the driving force control device according to claim 1 or 2,
The controller is
The provisional line is set as a straight line including at least two times of the traveling data within the most recent period that is a predetermined number of times after the latest accelerated traveling.
A driving force control apparatus characterized by that.
In the driving force control device according to claim 1 or 2,
The controller is
The driving force control characterized in that the provisional line is set as a straight line including the travel data of one time within the most recent period that is a predetermined number of times after the latest acceleration travel, and having the same inclination as the acceleration history line apparatus.
In the driving force control device according to any one of claims 1 to 5,
The controller is
The driving force control apparatus, wherein the provisional line is corrected so that a deviation between the provisional line and the latest travel data is reduced by bringing the provisional line closer to the latest travel data.

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