JP4982969B2 - Vehicle driving force control device - Google Patents

Description

  The present invention relates to a vehicle driving force control device, and more particularly, to a vehicle driving force control device that performs driving force control of a vehicle by an operation of shifting a transmission to a relatively low speed gear stage or gear ratio.

  When vehicle driving force control (deceleration control) is performed based on conditions ahead of the vehicle such as corner radius, road gradient, and inter-vehicle distance from the preceding vehicle, the engine speed is reduced by shifting down the shift stage of the automatic transmission. A technique of shift point control in which deceleration by force is applied to a vehicle is known.

  For example, Japanese Patent Laid-Open No. 2000-145937 (Patent Document 1) discloses a technique for performing downshift control according to road conditions based on road information stored in a navigation system.

JP 2000-145937 A

In a vehicle driving force control device that performs deceleration control, for example, when the vehicle is traveling in a state in which the vehicle behavior is likely to be affected, such as when turning determination of the vehicle or tire slip determination is performed, It is desired to control so that stability is not impaired.
In this case, in particular, after the downshift command is output, it is necessary to perform control so that the vehicle stability is not adversely affected by the increase in deceleration.
On the other hand, when the control for ensuring the stability of the vehicle is performed, it is desired to suppress the driver from feeling uncomfortable.

  An object of the present invention is a vehicle driving force control device that performs deceleration control, for example, when a vehicle travels in a state in which vehicle behavior is likely to be affected, such as when vehicle turning determination or tire slip determination is performed. An object is to provide a vehicle driving force control device capable of performing control in an optimal manner so that the stability of the vehicle is not impaired when the vehicle is in operation.

A vehicle driving force control device according to the present invention is a vehicle driving force control device that performs deceleration control of a vehicle based on a driver's intention to decelerate, and a controller that performs control for stabilizing the vehicle; An index value estimation detecting unit capable of estimating or detecting a plurality of index values that affect the running stability of the vehicle, and the control unit performs shifting based on the first index value. A control for stabilizing the vehicle after a shift is started based on a second index value, and performing a first control that is a control for stabilizing the vehicle after the start. there line different from the second control to the control content of the first control, the first index value indicates whether the state in which the vehicle is turning, the second index value, Indicates whether or not the vehicle tire has slippage greater than a predetermined value, and Control for Joka is prohibition of transmission, or is characterized in that by lowering the engagement oil pressure of the frictional engagement device of the transmission.
In the above, the index value corresponds to a traveling state of the vehicle capable of predicting that the vehicle is in an unstable state, or indicates that the vehicle is in an unstable state It can correspond to the running state of.

In the vehicle driving force control apparatus according to the present invention, when the first index value is estimated or detected under a first condition, control for stabilizing the vehicle is performed as the first control. In other words, when the second index value is estimated or detected under a second condition, control for stabilizing the vehicle is performed as the second control.
In the above, the first control may be prohibition of shifting, and the second control may be to reduce the engagement hydraulic pressure of the friction engagement device of the transmission.

In the vehicle driving force control apparatus according to the present invention, the first condition includes a first setting condition that the shift is not started, a second setting condition that the shift is not ended, and the end / non-end of the shift. It is any one of the third setting conditions that do not matter, and the second condition is any one of the first to third setting conditions.
In the above, the first to third setting conditions may be different in the degree of progress of the shift.

In the aspect of the present invention, is prohibited and the shift amount of the shift as before Symbol first control is prohibited when it is inhibited, when said shifting is inhibited as said second control It is characterized by being different from the shift amount.

In the aspect of the present invention, only a specific shift stage set pre Me, prohibition of the shifting, or, as characterized by a decrease in engagement oil pressure of the friction engagement device is performed Yes.

In the aspect of the present invention, when the slipperiness of a road surface on which pre-Symbol vehicle travels is detected or estimated to be equal to or more than the set value, the prohibition of the shifting, or the friction engagement device It is characterized in that the engagement hydraulic pressure is reduced.

  According to the vehicle driving force control device of the present invention, in the vehicle driving force control device that performs deceleration control, the vehicle behavior is likely to be affected, for example, when vehicle turning determination or tire slip determination is performed. When the vehicle is traveling in a state, the control for preventing the stability of the vehicle from being impaired can be performed in an optimal manner.

  Hereinafter, an embodiment of a vehicle driving force control device of the present invention will be described in detail with reference to the drawings.

(First embodiment)
The first embodiment will be described with reference to FIGS. 1 to 5. The present embodiment relates to a vehicle driving force control device that performs driving force control (corner control) by shifting a transmission based on information about a corner in front of the vehicle.

  If a vehicle turning determination or tire slip determination is made after a downshift command for corner control is output, if the determination is made before the start of the inertia phase of the shift, all the shifts are cancelled. Is considered. When there is a vehicle turning determination or tire slip determination, it is desirable to cancel the downshift from the viewpoint of vehicle stability, but if the shift is canceled after the inertia phase starts, a sense of incongruity (change in engine speed or vehicle acceleration) Therefore, the downshift is canceled only before the start of the inertia phase of the shift, and the downshift is executed as it is after the start of the inertia phase.

  In contrast, in the present embodiment, when a vehicle turning determination or tire slip determination is made after the downshift command is output, the determination is made after the inertia phase starts (after the start of shifting). Also, the shift is canceled. During the inertia phase, the output shaft torque usually increases with the progress of the shift. Therefore, when there is a vehicle turning determination or tire slip determination, the shift is canceled and the output shaft torque increases (decreases). (Increase in speed). That is, when vehicle turning determination or tire slip determination is made, the merit of vehicle stability is more important than the demerit that causes a sense of incongruity due to shift cancellation after the start of the inertia phase.

  Here, in the present embodiment, the following steps [1] and [2] are taken according to the state of the vehicle after the downshift command is output. As described above, canceling the shift after the start of the shift (after the start of the inertia phase) causes a sense of incongruity (change in engine speed or change in vehicle acceleration). Therefore, it is not preferable to cancel the shift unnecessarily. . Therefore, the shift cancel control is not performed uniformly regardless of the state of the vehicle after the downshift command is output, but based on the degree of influence on the vehicle stability. It is reasonable to change the treatment. Therefore, the control contents are different as follows for the shift canceling process when the vehicle turning determination is made after the downshift command is output and when the tire slip determination is made.

[1] When the vehicle turning determination is made, even if the vehicle turning determination is made after the start of the inertia phase, the vehicle turning determination is made before the time point when the gear shift ends (or a certain time point before the gear shift ends). If this happens, the shift is cancelled. For example, when a multiple-stage downshift command is output, and there is an unfinished shift at the time when the vehicle turning determination is made, the unfinished shift is canceled. Specifically, after the shift command from the 6th speed to the 4th speed is output, the vehicle turning determination is made, and when the vehicle turning determination is made, the shift from the 6th speed to the 5th speed is completed. If the shift from the fifth speed to the fourth speed has not been completed, the unfinished shift from the fifth speed to the fourth speed is cancelled.

  In the case of [1], unlike the case of [2] described later, the vehicle is in an unstable state (tire slipping) only when the vehicle turning determination is made (the vehicle is cornering). Is not determined), simply canceling the unfinished shift (in the above example, shifting from the 5th speed to the 4th speed), the gear stage before the unfinished shift (in the above example, 5th speed) is maintained, and the upshift is not performed from the gear position before the unfinished shift (5th speed in the above example).

[2] When the tire slip determination is made, even if the tire slip determination is made after the time point at which the gear shift ends (or at a certain time before the gear shift ends), the gear shift is canceled. Then, an upshift is performed to the shift stage before the shift, and the deceleration force is reduced. For example, when a multiple-stage downshift command is output, all shifts related to the downshift command are canceled regardless of whether or not the shift has not been completed. Specifically, after the shift command from the 6th speed to the 4th speed is output, tire slip determination is made, and when the tire slip determination is made, the shift from 6th speed to 5th speed is completed. When the shift from the fifth speed to the fourth speed has not been completed, all the shifts related to the shift command (shift from the sixth speed to the fourth speed) are canceled regardless of whether the shift has not been completed. Then, a return command (upshift command) to the shift stage (sixth speed) before the shift is output.

  If the shift is canceled after the end of the shift, there is a feeling that the deceleration is lost, and the engine speed also changes from increasing to decreasing, which may give the driver a sense of incongruity. However, if the tire slip determination is made, the vehicle may become unstable, and therefore all shifts are canceled prior to feeling.

  As described in detail below, the configuration of the present embodiment includes a transmission capable of changing a gear position or a gear ratio, a shift determination command means (manual shift, shift point control), and a braking force control means (brake or MG device), a destination road situation means for detecting the destination road situation (distance to corner R or corner approach), a means for controlling the shift determination command means based on the detection result by the destination road situation means, The premise is a means for making a turn determination and a means for making a tire slip determination.

  In FIG. 2, reference numeral 10 denotes a stepped automatic transmission, 40 denotes an engine, and 200 denotes a brake device. The automatic transmission 10 is capable of six-speed shifting by controlling the hydraulic pressure by energization / non-energization of the solenoid valves 121a, 121b, 121c. In FIG. 2, three electromagnetic valves 121a, 121b, and 121c are illustrated, but the number of electromagnetic valves is not limited to three. The solenoid valves 121a, 121b, and 121c are driven by a signal from the control circuit 130.

  The accelerator opening sensor 113 detects the accelerator opening. The throttle opening sensor 114 detects the opening of the throttle valve 43 disposed in the intake passage 41 of the engine 40. The engine speed sensor 116 detects the speed of the engine 40. The vehicle speed sensor 122 detects the rotation speed of the output shaft 120c of the automatic transmission 10 that is proportional to the vehicle speed. The shift position sensor 123 detects the shift position. The pattern select switch 117 is used when instructing a shift pattern.

  The navigation system device 95 has a basic function of guiding the host vehicle to a predetermined destination, and includes an arithmetic processing device and information (map, straight road, curve, uphill / downhill, highway) necessary for traveling the vehicle. Etc.), a first information detection device including a geomagnetic sensor, a gyrocompass, and a steering sensor, and a current position of the vehicle by radio navigation. It is for detecting a position, road conditions, etc., and is provided with a second information detection device including a GPS antenna and a GPS receiver.

  The tire slip determination unit 91 detects the presence or absence of tire slip. The tire slip determination unit 91 performs various conditions, for example, a rotational speed (driven wheel speed) of a front wheel (not shown) detected by a front wheel speed sensor (not shown) and a rear wheel (detected by a vehicle speed sensor 122). The presence / absence of tire slip is detected based on the difference in rotational speed (drive wheel speed).

  Here, the specific method of detecting the presence or absence of tire slip by the tire slip determination unit 91 is not particularly limited, and a known method can be appropriately employed. For example, in addition to the wheel speed difference before and after the above, the rate of change of wheel speed, ABS (anti-lock brake system), TRS (traction control system) and VSC (vehicle stability control) operation The presence or absence of tire slip can be detected using at least one of the relationship between the history, the acceleration of the vehicle, and the wheel slip ratio.

  The road surface μ detection / estimation unit 92 detects or estimates the slipperiness of the road surface represented by the road surface friction coefficient μ (whether the road surface is a low μ road). Here, the low μ road includes a bad road (including a case where the road surface has large unevenness or a step on the road surface). That is, the road surface μ detection / estimation unit 92 calculates the friction coefficient μ of the traveling road surface, and determines whether the road is a low μ road depending on whether the calculated friction coefficient μ exceeds a predetermined threshold value. Is determined.

  The road surface μ detection / estimation unit 92 predicts whether the road surface is a low μ road, based on information (navigation information, etc.) about the road surface scheduled to travel in the future. Here, the navigation information includes information on road surfaces (for example, non-paved roads) recorded in advance on a storage medium (DVD, HDD, etc.) as in the navigation system device 95, as well as past actual driving and other information. Information (including information indicating road conditions and information indicating weather conditions) obtained through communication (including vehicle-to-vehicle communication and road-to-vehicle communication) with other vehicles and communication centers. Such communications include road traffic information communication systems (VICS) and so-called telematics.

  The acceleration sensor 90 detects vehicle deceleration (deceleration acceleration). The manual shift determination unit 94 outputs a signal indicating the necessity of downshift (manual downshift) or upshift by the driver's manual operation based on the driver's manual operation.

  The inter-vehicle distance measuring unit 100 has a sensor such as a laser radar sensor or a millimeter wave radar sensor mounted on the front of the vehicle, and measures the inter-vehicle distance from the front vehicle. The relative vehicle speed measuring unit 115 includes a sensor such as a millimeter wave radar sensor, and can directly measure the relative vehicle speed of the front vehicle and the host vehicle. Here, the relative vehicle speed is (own vehicle speed−front vehicle speed). The inter-vehicle distance measuring unit 100 and the relative vehicle speed measuring unit 115 are configured by a single (identical) millimeter wave radar.

  The road gradient measurement / estimation unit 118 can be provided as a part of the CPU 131. The road gradient measurement / estimation unit 118 can measure or estimate the road gradient based on the acceleration detected by the acceleration sensor 90. Further, the road gradient measuring / estimating unit 118 may store the acceleration on the flat road in the ROM 133 in advance and obtain the road gradient by comparing with the acceleration actually detected by the acceleration sensor 90.

  The control circuit 130 includes an accelerator opening sensor 113, a throttle opening sensor 114, an engine speed sensor 116, a vehicle speed sensor 122, a shift position sensor 123, an acceleration sensor 90, a tire slip determination unit 91, a road surface μ detection / estimation unit 92, A signal indicating each detection / estimation result of the inter-vehicle distance measuring unit 100 and the relative vehicle speed measuring unit 115 is input, a signal indicating a switching state of the pattern select switch 117 is input, a manual shift determining unit 94, navigation A signal from the system unit 95 is input.

  The control circuit 130 is configured by a known microcomputer and includes a CPU 131, a RAM 132, a ROM 133, an input port 134, an output port 135, and a common bus 136. The input port 134 includes signals from the sensors 113, 114, 116, 122, 123, and 90, a signal from the switch 117, a signal from the navigation system device 95, a tire slip determination unit 91, and road surface μ detection. A signal from the estimation unit 92 and the manual shift determination unit 94, and a signal from each of the inter-vehicle distance measurement unit 100 and the relative vehicle speed measurement unit 115 are input. The output port 135 is connected to the electromagnetic valve driving units 138a, 138b, 138c and the brake braking force signal line L1 to the brake control circuit 230. A brake braking force signal SG1 is transmitted through the brake braking force signal line L1.

  The ROM 133 stores in advance a program in which the operations (control steps) shown in the flowchart of FIG. 1 are described, and a shift map for shifting the shift stage of the automatic transmission 10 and a shift control operation (not shown). ) Is stored. The control circuit 130 shifts the automatic transmission 10 based on various input control conditions.

  The brake device 200 is controlled by a brake control circuit 230 that receives a brake braking force signal SG1 from the control circuit 130, and brakes the vehicle. The brake device 200 includes a hydraulic control circuit 220 and braking devices 208, 209, 210, and 211 provided on the wheels 204, 205, 206, and 207 of the vehicle, respectively. Each of the braking devices 208, 209, 210, and 211 controls the braking force of the corresponding wheels 204, 205, 206, and 207 when the hydraulic pressure is controlled by the hydraulic control circuit 220. The hydraulic control circuit 220 is controlled by the brake control circuit 230.

  The hydraulic control circuit 220 performs brake control by controlling the braking hydraulic pressure supplied to each braking device 208, 209, 210, 211 based on the brake control signal SG2. The brake control signal SG2 is generated by the brake control circuit 230 based on the brake braking force signal SG1. The brake braking force signal SG1 is output from the control circuit 130 of the automatic transmission 10 and input to the brake control circuit 230. The brake force applied to the vehicle during the brake control is determined by a brake control signal SG2 generated by the brake control circuit 230 based on various data included in the brake braking force signal SG1.

  The brake control circuit 230 is configured by a known microcomputer and includes a CPU 231, a RAM 232, a ROM 233, an input port 234, an output port 235, and a common bus 236. A hydraulic control circuit 220 is connected to the output port 235. The ROM 233 stores an operation for generating the brake control signal SG2 based on various data included in the brake braking force signal SG1. The brake control circuit 230 controls the brake device 200 (brake control) based on each input control condition.

  The operation of this embodiment will be described with reference to FIGS.

  FIG. 3 is a chart for explaining the deceleration control of the present embodiment. FIG. 3 shows the control execution boundary L, the required deceleration 401, the target turning vehicle speed Vreq, the road shape top view, and the point a where the accelerator is OFF (the accelerator opening is fully closed).

[Step S10]
In step S10, the control circuit 130 determines whether or not the accelerator is in an OFF state (fully closed) based on the signal from the accelerator opening sensor 113. If it is determined as a result of step S10 that the accelerator is in an OFF state, the process proceeds to step S20. When the accelerator is fully closed (step S10-Y), it is determined that the driver intends to decelerate, and the deceleration control of this embodiment is performed. On the other hand, if it is not determined that the accelerator is in the OFF state, the process proceeds to step S180. As described above, in FIG. 3, the accelerator opening is zero (fully closed) at the position (time point) a. It is assumed that the gear position at the position of symbol a is 6th speed.

[Step S20]
In step S20, the control circuit 130 checks the flag F. As a result, if the flag F is 0, the process proceeds to step S30, and if the flag F is 1 or 2, the process proceeds to step S60. When this control flow is executed, the flag F is initially 0, so the process proceeds to step S30.

[Step S30]
In step S30, the control circuit 130 determines whether or not the present control is necessary based on, for example, the control execution boundary line L. In the determination, in FIG. 3, if it is located above the control execution boundary line L due to the relationship between the current vehicle speed and the distance to the entrance 403 of the corner 402, it is determined that this control is necessary, and the control execution boundary line If it is positioned lower than L, it is determined that this control is unnecessary. As a result of the determination in step S30, if it is determined that this control is necessary, the process proceeds to step S40. If it is determined that this control is not necessary, this control flow is returned.

  The control execution boundary line L is a relationship between the current vehicle speed and the distance to the point c just before the entrance 403 of the corner 402, unless a deceleration exceeding a preset deceleration by normal braking acts on the vehicle. This is a line corresponding to a range in which the target turning vehicle speed Vreq cannot be reached at the point c before the entrance 403 of the corner 402 (the corner 402 cannot be turned at a desired turning G). That is, when the vehicle is positioned above the control execution boundary L, in order to reach the target turning vehicle speed Vreq at the point c before the entrance 403 of the corner 402, the deceleration by the normal braking set in advance is exceeded. It is necessary for the deceleration to act on the vehicle.

  Therefore, when the vehicle is positioned above the control execution boundary L, the driving force control corresponding to the corner R of the present embodiment is executed (step S50), and the driver operates the brake by increasing the deceleration. Even if there is no amount or the amount of operation is relatively small (even if the foot brake is stepped on only a little), the target turning vehicle speed Vreq can be reached at a point c before the entrance 403 of the corner 402. .

  As the control execution boundary line L of the present embodiment, a control execution boundary line used for shift point control corresponding to a conventional general corner R can be applied as it is. The control execution boundary line L is created by the control circuit 130 based on the data input from the navigation system device 95 and indicating the distance between R405 of the corner 402 and the corner.

  In the present embodiment, in FIG. 3, the time point corresponding to the sign “a” at which the accelerator opening is zero is located above the control execution boundary line L, so it is determined that this control is necessary (step S <b> 30 -Y). ), Go to step S40.

[Step S40]
In step S <b> 40, the control circuit 130 determines a gear stage to be selected when the automatic transmission 10 is controlled to shift (shift down). In determining the speed to be selected, first, the required deceleration is obtained, and then the speed to be selected is determined based on the required deceleration. Hereinafter, the calculation of the required deceleration will be described as (A), and then the determination of the shift speed to be selected will be described as (B).

(A) Calculation of Required Deceleration The required deceleration is calculated by the control circuit 130. The necessary deceleration is a deceleration required to turn the other corner at a predetermined desired turning G (in order to enter the corner at a desired vehicle speed Vreq). In FIG. 3, the necessary deceleration is indicated by reference numeral 401.

  In FIG. 3, the horizontal axis indicates the distance. As shown in the “top view of the road shape”, the far corner 402 exists from the point 403 to the point 404. A target turn corresponding to the radius (or curvature) R405 of the corner 402 at a point c offset by a predetermined amount from the entrance 403 of the corner 402 in order to turn the corner 402 at a preset desired turn G. It has to be decelerated to the vehicle speed Vreq. That is, the target turning vehicle speed Vreq is a value corresponding to R405 of the corner 402.

  In order to decelerate from the vehicle speed at the location a where the accelerator is determined to be fully closed in step S10 to the target turning vehicle speed Vreq required at the point c just before the entrance 403 of the corner 402, this is indicated by the required deceleration 401. Such deceleration is required. The control circuit 130 is based on the current vehicle speed input from the vehicle speed sensor 122, the distance from the current position to the entrance 403 of the corner 402 (point c before) and the R405 of the corner 402, which are input from the navigation system device 95. The necessary deceleration 401 is calculated.

(B) Determination of the shift speed to be selected In the ROM 133, vehicle characteristic data indicating the deceleration G for each vehicle speed of each shift speed when the accelerator is OFF as shown in FIG.

  Here, assuming that the output rotational speed is 1000 [rpm] and the required deceleration 401 is −0.18 G, in FIG. 4, this corresponds to the vehicle speed when the output rotational speed is 1000 [rpm]. In addition, it can be seen that the shift speed that is the closest to −0.18G of the required deceleration 401 is the fourth speed. Thus, in the case of the above example, in step S40, it is determined that the gear position to be selected (down gear position) is the fourth speed.

  In this example, the speed stage closest to the necessary deceleration 401 is selected as the speed stage to be selected. However, the speed stage to be selected is a deceleration of the required deceleration 401 or lower (or higher). Thus, the gear position that provides the closest deceleration to the required deceleration 401 may be selected. Step S50 is executed after step S40.

[Step S50]
In step S50, the control circuit 130 outputs a shift command related to the gear stage to be selected, which is determined in step S40. That is, a downshift command (shift command) from the sixth speed to the fourth speed is output from the CPU 131 of the control circuit 130 to the solenoid valve driving units 138a to 138c.

  In response to the downshift command, the solenoid valve driving units 138a to 138c energize or de-energize the solenoid valves 121a to 121c. As a result, the automatic transmission 10 performs a shift instructed by the downshift command.

  When the downshift command is determined by the control circuit 130 at the location (time point) corresponding to the symbol a in FIG. 3 (step S30-Y) at the same time as it is necessary to downshift as the shift point control of this embodiment (step S30-Y), Is output at a time corresponding to the symbol a in FIG. As a result, the automatic transmission 10 starts a downshift operation toward the gear position to be selected (fourth speed in the above example) determined as described above from the time corresponding to the symbol a in FIG. As the hydraulic pressure of the engaging clutch increases, the engine braking force (output shaft torque) increases, and the deceleration due to the gear position of the automatic transmission 10 increases from the point of the symbol a. Step S60 is executed after step S50.

[Step S60]
In step S <b> 60, the control circuit 130 determines the presence or absence of tire slip based on the signal input from the tire slip determination unit 91. As a result of the determination, if it is determined that there is a tire slip exceeding a predetermined value, the process proceeds to step S70, and if not, the process proceeds to step S80.

  In step S60, it is determined whether or not the road surface is a low μ road based on not only the presence / absence of tire slip but also a signal input from the road surface μ detection / estimation unit 92. If it is determined that the road is a low μ road, the process proceeds to step S70. If it is determined that the road is not in any case, the process may proceed to step S80.

[Step S70]
In step S70, the control circuit 130 relates to the downshift command regardless of whether the current time is before or after the end of the shift related to the downshift command (or before or after the end of the shift). The shift is canceled and the upshift is performed to the shift stage before the shift according to the downshift command. That is, all the shift commands related to the downshift command (shift command from the 6th speed to the 4th speed) are canceled, and the return command (upshift command) for the shift stage (6th speed) before the shift related to the downshift command. Is output. Following step S70, step S80 is performed.

[Step S80]
In step S80, the control circuit 130 determines whether or not the vehicle is turning, that is, whether or not the vehicle has entered the corner 402 (vehicle turning determination). The control circuit 130 performs the determination in step S80 based on the size of the lateral G of the vehicle. Alternatively, the determination in step S80 is performed based on the data input from the navigation system device 95 and indicating the current position of the vehicle and the position of the entrance 403 of the corner 402. If the result of determination in step S80 is that the vehicle has entered the corner 402 (step S80-Y), the flag F is set to 2 (step S90), and the process proceeds to step S100. Proceed to step S160.

  In the first stage in which this control flow is performed, the vehicle has not entered the corner 402 (step S80-N), so the process proceeds to step S160.

[Step S160]
In step S160, the control circuit 130 checks the flag F. As a result, if the flag F is 0, the process proceeds to step S170 and the flag F is set to 1 and the control flow is reset. If the flag F is 1, the control flow is reset and the flag F is 2. If so, the process proceeds to step S140.

  When this control flow is executed, the flag F is initially 0, so that the flag F is set to 1 (step S170) and this control flow is reset. If it is fully closed (step S10-Y), since the flag F is 1 (step S20-1), the process proceeds to step S60 and is repeated until the condition of step S80 is satisfied.

[Step S100]
In step S100, the control circuit 130 regulates a new upshift. During cornering after entering the corner 402, it is restricted that the gear is shifted up to a higher gear than the gear associated with the downshift command output in step S50 (fourth gear in the above example). Is done. However, the upshift (return) to the gear stage before the shift related to the downshift command performed in step S70 is not regulated. Normally, even in a shift point control for a general corner, an upshift during cornering after entering the corner is prohibited. After step S100, the process proceeds to step S110.

[Step S110]
In step S110, the control circuit 130 determines whether or not there is an unfinished downshift. In particular, when a multiple-stage shift command is output, since it takes time to complete all shifts, the determination in step S110 is performed. Here, the unfinished downshift means, for example, a shift in which the inertia phase has not finished. In step S100, since a new downshift is not prohibited, the shift to be determined in step S110 is the shift related to the downshift command output in step S50 during non-cornering and during cornering ( Turning determination: both of the shifts related to the output downshift command (after step S80 is performed).

  As a result of the determination in step S110, if it is determined that there is an unfinished downshift (step S110-Y), the process proceeds to step S120. If it is determined that there is no downshift (step S110-N), the process proceeds to step S130. In this example, among the shift command (shift command from 6th speed to 4th speed) related to the downshift command output in step S50, the shift from 6th speed to 5th speed has been completed, but the 5th speed It is assumed that the shift from 4 to 4 has not been completed. In this case, the result of determination in step S110 is affirmative and the process proceeds to step S120.

[Step S120]
In step S120, the control circuit 130 cancels the shift determined that the shift has not been completed in step S110, and the shift stage is the shift stage before the unfinished shift (the completed shift is Is maintained at the shift stage after being performed). In this example, since it is determined in step S110 that the shift from the fifth speed to the fourth speed has not been completed, in step S120, the shift from the fifth speed to the fourth speed is canceled, and the shift speed is 5 (No upshift to 6th gear is performed).

[Step S130]
In step S130, the control circuit 130 determines whether or not the vehicle is turning, that is, whether or not the corner 402 has escaped (vehicle turning determination). The control circuit 130 can make a turn determination in the same manner as in step S80. If the result of determination in step S130 is that the corner 402 has been escaped (step S130-N), the flag restriction set in step S100 is released (step S140), and the flag F is set to 0. (Step S150), and then the control flow is reset. On the other hand, if the result of determination in step S130 is that the corner 402 has not escaped (step S130-Y), this control flow is reset.

  Since the vehicle has not escaped from the corner 402 at the first stage when the control flow is performed (step S130-Y), the control flow is reset, and the accelerator is fully closed in the second control flow ( In step S10-Y), since the flag F is 2 (step S20-2), the process proceeds to step S80 (same vehicle turning determination as in step S130) through step S60, and the vehicle is not turning. Until it is determined that the corner 402 has escaped (step S80-N), step S130 is determined affirmatively and the control flow is repeated. In the control flow, if it is determined that the corner 402 has escaped as a result of the determination in step S80 (step S80-N), the flag F is determined to be 2 in step S160, and the process proceeds to step S140.

[Step S180] to [Step S240]
Before the deceleration control of this embodiment is started (with flag F = 0), if the accelerator is not fully closed (step S10-N), flag F is checked (step S180) and flag F is 0. If the flag F is 1, it is determined whether or not the vehicle is turning (step S190). If the result of the determination is that the vehicle is not turning (step S190-N), the present control flow is reset. The control flow is reset and waits until it is determined that the vehicle is turning (step S190-Y).

  If the result of determination in step S190 is that the vehicle is turning (step S190-Y), the flag F is set to 2 (step S200), and upshift regulation is performed (step S210). Thereafter, in step S220, it is determined whether or not the vehicle is turning again. If the vehicle is turning (step S220-Y), it is determined that the vehicle is not turning via steps S10 and S180 (step S220). Wait for -N). As a result of the determination in step S220, if it is determined that the vehicle is not turning (step S220-N), the shift restriction is canceled (step S230), the flag F is reset to 0 (step S240), and this control is performed. The flow is reset.

  According to this embodiment described above, the following effects can be obtained.

First, effects when the vehicle turning determination is performed will be described.
According to the present embodiment, when cornering is being performed (step S80-Y), a new upshift is restricted (step S100) until the corner is exited (step S130-N), and has not been completed. The shift command is canceled for the downshift (step S110-Y, step S120). If cornering is in progress, an increase in vehicle deceleration may impair vehicle stability, so an unfinished downshift command is canceled.

  As shown in FIG. 3, when the accelerator is returned at a point “a” before the corner 402, the shift control of this embodiment is performed. Even if the vehicle enters the corner 402 (after the entrance 403), the road entrance curvature is not so large on the actual road, so the turning judgment (determination that cornering is in progress) is slightly delayed from the entrance 403 of the corner 402. (In FIG. 3, turning determination is performed at point d). In addition, there is a time delay between the output of the shift command and the completion of the shift. For these reasons, there is a possibility that a shift command is output before turning determination that cornering is being performed, and a shift is performed during cornering.

  As shown in FIG. 5, conventionally, if a turning determination is made that cornering is being performed before the time t1 when the inertia phase starts, the shift is canceled (not shown), but the inertia phase is started. If it is determined that cornering is in progress after time t1 (time t2 in the figure), the gear shift is continued and the clutch engagement pressure 501 increases as it is, and the deceleration (negative output shaft torque 502) occurs. Was increasing.

  On the other hand, in this embodiment, even if it is determined that cornering is being performed after the time t1 when the inertia phase is started (time t2), there is an unfinished downshift at that time. In this case, the shift is canceled (reference numerals 501a and 502a) at time t3 after a slight delay. As a result, it is possible to prevent an increase in deceleration by ΔT1 compared to the case where shifting is continued as in the prior art, which is advantageous in terms of vehicle stability.

Next, a case where tire slip determination is performed will be described.
If there is tire slip (step S60-Y), regardless of whether the shift is completed or not, all of the downshift commands are canceled and the gears before the downshift related to the downshift commands are performed. Upshifting is performed (step S70). When the tire slip determination is made, the vehicle is in an unstable state, so regardless of the degree of progress of the downshift, all of the downshift is canceled and the gear position before the downshift is performed. By performing an upshift, the deceleration is reduced and vehicle stability is ensured.

  On the other hand, when the vehicle turning determination is made, unlike the case where the tire slip determination is performed, the vehicle is unstable because the vehicle is relatively likely to become unstable because the vehicle is cornering. It does not mean that the tire is slipping (tire slip determination is made). Therefore, it is not necessary to decrease the deceleration as the tire slip determination is made, and the gear stage before the unfinished shift is held is retained only by canceling the unfinished shift (the unfinished shift). The upshift is not performed from the gear position before the gear shift is performed). Canceling the shift after the start of the shift (after the start of the inertia phase) causes a sense of incongruity (change in engine speed or change in vehicle acceleration). In this case, in particular, canceling the shift after the shift has ended ends up feeling uncomfortable. Since it is large, only unfinished shifts are cancelled.

  As described above, in this embodiment, the state relating to the stability of the vehicle (how much the deceleration needs to be reduced) and the uncomfortable feeling associated with the cancellation of the shift after the start of the shift (after the start of the inertia phase) Depending on the balance, an optimal measure is taken regarding the cancellation of the shift.

(First modification of the first embodiment)
In the first embodiment, the corner control has been described as being performed by controlling the gear position of the stepped automatic transmission 10, but instead, the CVT gear ratio may be similarly controlled. it can.

(Second modification of the first embodiment)
In the first embodiment, the corner control is performed only by the shift control of the automatic transmission, but can be performed by the cooperative control of the automatic transmission and the brake. In this case, not only the shift control of the automatic transmission 10 but also the feedback control of the brake device 200 is executed by the brake control circuit 230. The brake feedback control means that the braking force is controlled according to the deviation between the target deceleration (required deceleration 401) and the actual deceleration of the vehicle.

  The brake feedback control is started at the location a where the downshift command is output. That is, a signal indicating the required deceleration 401 is output from the control circuit 130 to the brake control circuit 230 via the brake braking force signal line L1 as the brake braking force signal SG1. The brake control circuit 230 generates a brake control signal SG2 based on the brake braking force signal SG1 input from the control circuit 130, and outputs the brake control signal SG2 to the hydraulic control circuit 220.

  The hydraulic pressure control circuit 220 controls the hydraulic pressure supplied to the braking devices 208, 209, 210, and 211 based on the brake control signal SG2, so that the brake force (brake control amount 302) as instructed in the brake control signal SG2 is controlled. ).

  In the feedback control of the brake device 200, the target value is the necessary deceleration 401, the control amount is the actual deceleration of the vehicle, the control target is the brake (braking devices 208, 209, 210, 211), and the operation amount is This is a brake control amount, and the disturbance is mainly a deceleration due to a shift of the automatic transmission 10. The actual deceleration of the vehicle is detected by the acceleration sensor 90 or the like.

  That is, in the brake device 200, the brake braking force (brake control amount) is controlled so that the actual deceleration of the vehicle becomes the required deceleration 401. That is, the brake control amount is set so as to cause a deceleration that is insufficient for the deceleration due to the shift of the automatic transmission 10 when the required deceleration 401 is generated in the vehicle.

  Note that the brake control in the second modified example may be performed by using a braking device that generates a braking force on the vehicle, such as a regenerative braking by an MG device provided in the power train system, instead of the brake. .

(Third Modification of First Embodiment)
In the present modification, in the first embodiment, the shift for canceling the shift command is only the shift to a specific low speed stage at each of the vehicle turning determination and the tire slip determination. If the shift command is canceled during the inertia phase, a feeling of missing deceleration occurs, and the engine speed also changes from increasing to decreasing, which may cause discomfort. For this reason, the target of canceling the shift command during the inertia phase is limited to a shift to a specific low speed stage where vehicle stability should be prioritized. In addition, regarding the cancellation of the shift command before the start of the inertia phase, since the shift amount is limited in the current transmission, even if all the shifts are canceled, there will be no major trouble, but in the future transmissions This is because canceling all shifts may cause a problem as the number of stages increases and the deceleration increases.

(Fourth modification of the first embodiment)
A fourth modification of the first embodiment will be described with reference to FIG.

  In this modification, as shown in FIG. 6, the road surface μ detection / estimation unit 92 cancels the shift command for the unfinished shift at the time of turning determination (step S120). The determination is limited to the case (step S105-Y). As described above, if the gear shift command is canceled during the inertia phase, the feeling of missing the deceleration occurs, and the engine speed also changes from increasing to decreasing, which may cause a sense of incongruity. For this reason, at the time of turning determination, the shift command is canceled during the inertia phase only in the situation (step S105-Y) that is determined to be a low μ road as the situation where vehicle stability should be emphasized. Yes.

(Fifth Modification of First Embodiment)
A fifth modification of the first embodiment will be described with reference to FIG.

  The present modification relates to a criterion for determining whether or not the shift is completed in step S110 of the first embodiment. FIG. 7 shows a type of shift operation in which the engagement pressure is reduced at the end of the shift. At the end of the shift, the normal output shaft torque 502 suddenly increases. As indicated by reference numeral 502f, the engagement hydraulic pressure 501f is decreased in order to avoid an increase in the deceleration. Thus, in the case of reducing the engagement pressure 502f at the end of the shift, the maximum point of deceleration (the maximum point of the engagement pressure, that is, whether the decrease of the engagement pressure has started) is determined as the shift end timing. Can be considered.

(Second Embodiment)
The second embodiment will be described with reference to FIG.
In the second embodiment, the description of the same points as in the first embodiment will be omitted.

  In the first embodiment, when the turning determination is made (step S80-Y in FIG. 1), the shift is canceled for the unfinished shift (step S120). On the other hand, in the second embodiment, as shown in step SA120 in FIG. 8, the clutch engagement pressure can be reduced for the incomplete shift when the turning determination is performed. Since the output shaft torque during the inertia phase is proportional to the engagement pressure, the shift time increases, but this is advantageous in terms of vehicle stability.

  In the second embodiment, as shown in FIG. 5, even when the turning is determined after the time t1 when the inertia phase is started (time t2), it is related to the time t3 after a slight delay. The resultant pressure is reduced (reference numerals 501b and 502b). As a result, it is possible to prevent an increase in deceleration by ΔT2 as compared with the conventional case where shifting is continued, which is advantageous in terms of vehicle stability.

(First Modification of Second Embodiment)
In the present modification, in the second embodiment, even after the inertia phase is started (during the inertia phase), the shift for reducing the engagement pressure is only a shift to a specific low speed stage. If the engagement pressure is reduced during the inertia phase, the feeling of deceleration is lost, and the engine speed also changes from increasing to decreasing, which may cause discomfort. For this reason, the target for lowering the engagement pressure during the inertia phase is limited to shifting to a specific low speed stage where vehicle stability should be prioritized.

(Third embodiment)
A third embodiment will be described with reference to FIG.
In the third embodiment, the description of the same points as in the above embodiment will be omitted.

  In the first embodiment, when the vehicle turning determination is made, even when the vehicle turning determination is made after the start of the inertia phase, from the time when the gear shift ends (or a certain time before the gear shift ends). If the shift is canceled, the shift is canceled, and if the tire slip determination is made, the tire slip determination is made after the end of the shift (or at a certain time before the end of the shift). Even in the case where it is made, it has been described that the shift is canceled and the upshift is performed to the shift stage before the shift. That is, in the said 1st Embodiment, the combination of No4 was demonstrated in FIG.

  According to the first embodiment (No. 4), in particular, when the tire slip determination is made after the shift is completed and the steering amount is large, the vehicle is likely to be in an unstable state. However, when the tire slip determination is made, the shift is canceled, which contributes to ensuring the stability of the vehicle.

  On the other hand, in the third embodiment, as shown in the combination of No. 3 in FIG. 12, when the vehicle turning determination is made before the start of the inertia phase (step SC111-Y in FIG. 9), the shift is performed. Canceled (step SC120), and when the tire slip determination is made (step SC60-Y), the tire slip determination is made after the time when the gear shift ends (or some time before the gear shift ends). Even in this case, the shift is canceled and an upshift is performed to the shift stage before the shift (step SC70).

  In the third embodiment (No. 3), the processing related to the shift cancellation at the time of vehicle turning determination is the same as that of the prior art (No. 1), and when the tire slip determination that makes the vehicle more likely to be unstable is made, Similar to the first embodiment, the procedure is to cancel even after the end of a shift.

(Fourth embodiment)
The fourth embodiment will be described with reference to FIG.
In the fourth embodiment, the description of the same points as in the above embodiment will be omitted.

  In the fourth embodiment, as shown in the combination of No. 2 in FIG. 12, when the vehicle turning determination is made before the start of the inertia phase (step SD111-Y in FIG. 10), the shift is canceled (step SD120). When the tire slip determination is made (step SD60-Y), even when the tire slip determination is made after the start of the inertia phase, the time point at which the shift ends (or before the shift ends) If it is made before (time point) (step SD65-Y), the shift is canceled (step SD70).

  In the fourth embodiment (No. 2), the processing related to the shift cancellation at the time of vehicle turning determination is the same as in the prior art (No. 1), and when the tire slip determination that makes the vehicle more likely to be unstable is made, Even if the tire slip determination is made after the start of the inertia phase, if the change is made before the end of the shift, the shift is canceled.

  In addition, as shown in No. 5 in FIG. 12, when the vehicle turning determination is performed, even if the vehicle turning determination is made after the time point at which the shift is completed, the shift is canceled. The treatment of upshifting to the gear position before the gear change is considered to be an excessive treatment and is not adopted.

(Fifth embodiment)
The fifth embodiment will be described with reference to FIG.
In the fifth embodiment, the description of the same points as in the above embodiment will be omitted.

  In the first embodiment, when the downshift control (corner control) is performed based on the corner R or the distance to the corner (step S50 in FIG. 1), when the vehicle turning determination is made, the vehicle turning determination is performed. However, even if it is made after the start of the inertia phase, if it is made before the end of the gear shift, the gear shift is canceled, and if the tire slip judgment is made, the tire slip judgment However, even when the shift is made after the end of the shift, the shift is canceled and an upshift is performed to the shift stage before the shift.

  On the other hand, in the fifth embodiment, downshift control is performed as deceleration control (uphill / downhill control) performed based on the road gradient, control (follow-up control) based on the inter-vehicle distance from the vehicle ahead of the vehicle, or manual shift. When the vehicle turning determination is made (step SE30-Y in FIG. 11), even if the vehicle turning determination is made after the start of the inertia phase, the shift is completed before the end of the shift. When the shift is made, the shift is canceled, and when the tire slip determination is made, the shift is canceled even if the tire slip determination is made after the time when the shift ends. At the same time, an upshift is performed to the shift stage before the shift.

  That is, the downshift command in step SE30 in FIG. 11 does not include a downshift command that crosses the shift line according to the normal shift map as the vehicle speed decreases, but it is based on deceleration control or manual shift based on other travel environments. A downshift command is included.

  In the fifth embodiment, when the vehicle is not cornering and there is no tire slip (step SE130-N), the shift restriction is released (step SE140), and this control ends.

  As a modified example of the fifth embodiment, although not shown, when the vehicle is not cornering, that is, when traveling on a straight road and the downshift command (step SE30) is output as a manual shift, shift regulation is performed. Further, it is possible to configure so that the shift cancellation for the incomplete shift and the cancellation of all shifts at the time of tire slip determination including after the shift end is not performed. When a downshift command is output by manual shift during non-cornering, there is little demand for ensuring vehicle stability, and the driver's intention is prioritized.

  Further, in the above description, the deceleration indicating the amount that the vehicle should decelerate has been described using the deceleration acceleration (G), but it is also possible to control based on the deceleration torque.

It is a flowchart which shows operation | movement of 1st Embodiment of the driving force control apparatus for vehicles of this invention. It is a schematic block diagram of 1st Embodiment of the driving force control apparatus for vehicles of this invention. It is a figure which shows operation | movement of 1st Embodiment of the driving force control apparatus for vehicles of this invention. It is a figure which shows the deceleration for every vehicle speed of each gear stage in 1st Embodiment of the vehicle driving force control apparatus of this invention. It is a figure which shows a part of effect of 1st Embodiment of the driving force control apparatus for vehicles of this invention. It is a flowchart which shows operation | movement of the 4th modification of 1st Embodiment of the driving force control apparatus for vehicles of this invention. It is a figure for demonstrating the gear shift completion time in the 5th modification of 1st Embodiment of the vehicle drive force control apparatus of this invention. It is a flowchart which shows operation | movement of 2nd Embodiment of the driving force control apparatus for vehicles of this invention. It is a flowchart which shows operation | movement of 3rd Embodiment of the driving force control apparatus for vehicles of this invention. It is a flowchart which shows operation | movement of 4th Embodiment of the driving force control apparatus for vehicles of this invention. It is a flowchart which shows operation | movement of 5th Embodiment of the driving force control apparatus for vehicles of this invention. It is the figure which compared operation | movement of each embodiment of the driving force control apparatus for vehicles of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Automatic transmission 40 Engine 90 Acceleration sensor 91 Tire slip determination part 92 Road surface μ detection and estimation part 94 Manual shift determination part 95 Navigation system apparatus 100 Inter-vehicle distance measurement part 113 Accelerator opening degree sensor 114 Throttle opening degree sensor 115 Relative vehicle speed measurement part 116 Engine Speed Sensor 117 Pattern Select Switch 118 Road Gradient Measurement / Estimation Unit 122 Vehicle Speed Sensor 123 Shift Position Sensor 130 Control Circuit 131 CPU
133 ROM
200 Brake device 230 Brake control circuit 401 Required deceleration 402 Corner 403 Inlet 405 Corner R
501 Clutch engagement pressure 501a Clutch engagement pressure 501b Clutch engagement pressure 502 Output shaft torque 502a Output shaft torque 502b Output shaft torque a Point c Point Vreq Target turning vehicle speed L Control execution boundary line L1 Brake braking force signal line SG1 Brake braking force Signal SG2 Brake control signal

Claims (6)

A vehicle driving force control device that performs vehicle deceleration control based on a driver's intention to decelerate,
A control unit that performs control for stabilizing the vehicle;
An index value estimation detection unit capable of estimating or detecting a plurality of index values that affect the running stability of the vehicle,
The control unit performs a first control that is a control for stabilizing the vehicle after a shift is started based on the first index value, and performs a shift based on the second index value. There the row different from the second control to the control content of the vehicle is a control for stabilizing the first control after but is started,
The first index value indicates whether or not the vehicle is turning.
The second index value indicates whether the tire of the vehicle has a slip of a predetermined value or more,
The vehicle driving force control device according to claim 1, wherein the control for stabilizing the vehicle is prohibition of shifting or lowering an engagement hydraulic pressure of a friction engagement device of the transmission . The vehicle driving force control device according to claim 1 ,
When the first index value is estimated or detected under a first condition, control for stabilizing the vehicle is performed as the first control,
When the second index value is estimated or detected under a second condition, a control for stabilizing the vehicle is performed as the second control. apparatus. In the vehicle driving force control device according to claim 2 ,
The first condition is any one of a first setting condition that the shift is not started, a second setting condition that the shift is not ended, and a third setting condition that does not matter whether the shift is finished or not finished. On the other hand,
The second condition is any one of the first to third setting conditions. The vehicle driving force control apparatus according to claim 1, wherein: In the vehicle driving force control device according to any one of claims 1, 2, and 3 ,
Characterized in that the shift as before Symbol first control and the shift amount is prohibited when it is prohibited, and the gear amount is prohibited when the shift is inhibited as said second control is different A vehicle driving force control device. The vehicle driving force control device according to claim 1 ,
Only a specific shift speed that has been pre-Me set, prohibition of the shifting, or the vehicle driving force control apparatus characterized by reduction of the engagement oil pressure of the friction engagement device is performed. In the vehicle driving force control device according to claim 1 or 5 ,
Characterized when the slipperiness of a road surface on which pre-Symbol vehicle travels is detected or estimated to be equal to or more than the set value, the prohibition of the shifting, or, that the decrease in engagement oil pressure of the friction engagement device is performed A vehicle driving force control device.

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