JP2019156326A - Drive support control device for vehicle - Google Patents

Abstract

To provide a drive support control device for a vehicle which shifts a state to a constant speed travel mode by one-pedal operation even when a vehicle speed is not stabilised in travel.SOLUTION: A drive support control device comprises: a CVT control unit 8 and an engine control unit 9 as drive force control means; and a drive support control unit 14. The drive support control unit 14 comprises a constant speed travel control part 14a for executing a constant speed travel mode for maintaining a vehicle speed by drive force control for making an actual vehicle speed VSP to match a target vehicle speed VSPwhen the target vehicle speed VSPis set. The constant speed travel control part 14a sets the actual vehicle speed VSP when an accelerator opening degree APO becomes in a constant speed region C to the target vehicle speed VSPand starts the constant speed travel mode, when the accelerator opening degree by an accelerator operation by a driver becomes in the constant speed region C from a lower threshold α to an upper threshold β set to an intermediate accelerator opening degree region, in travel.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a vehicle driving support control device having a constant speed traveling control function.

  Conventionally, when the condition that the vehicle speed is equal to or higher than a predetermined value and the vehicle speed fluctuation during a predetermined period is equal to or lower than the predetermined value is satisfied, a speed control control mode for maintaining the vehicle speed set according to the depression amount of the accelerator pedal is started. Then, after the speed control control mode is started, a vehicle speed control device is described that controls the driving force so that the vehicle speed changes at a predetermined change rate when the accelerator depression speed or the accelerator depression return speed is equal to or higher than a predetermined speed. (For example, refer to Patent Document 1).

JP, 2006-185744, A

  In the conventional apparatus, the speed control control mode for maintaining the vehicle speed is not started unless the condition that the vehicle speed is equal to or higher than a predetermined value and the vehicle speed fluctuation during the predetermined period is equal to or lower than the predetermined value is satisfied. For this reason, there is a problem that the speed control control mode cannot be entered in a scene in which the vehicle speed changes and is not stable, such as when traveling on a road surface with a large gradient change.

  The present invention has been made paying attention to the above problem, and an object thereof is to enter a constant speed traveling mode by one-pedal operation even when the vehicle speed is not stable during traveling.

In order to achieve the above object, a driving support control device for a vehicle according to the present invention includes driving force control means and driving support control means.
When the target vehicle speed is set, the driving support control means is provided with a constant speed traveling control unit that executes a constant speed traveling mode in which the vehicle travels while maintaining the vehicle speed by driving force control that matches the actual vehicle speed with the target vehicle speed.
The constant speed travel control unit enters the constant speed region when the accelerator opening by the driver's accelerator operation enters the constant speed region from the lower threshold set in the intermediate accelerator opening range to the upper threshold during driving. The actual vehicle speed is set to the target vehicle speed, and the constant speed running mode is started.

  Thus, by giving the start condition of the constant speed traveling mode according to the accelerator operation condition of the driver, it is possible to enter the constant speed traveling mode by one pedal operation even when the vehicle speed is not stable during traveling.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall system diagram showing a drive system and a control system of an engine vehicle equipped with a belt type continuously variable transmission to which a driving support control device of Example 1 is applied. It is a shift schedule figure which shows an example of the D range continuously variable transmission schedule used when the continuously variable transmission control in automatic transmission mode is performed by a variator. 1 is a schematic diagram showing a constant speed traveling control system of Example 1. FIG. 4 is a flowchart illustrating a flow of a constant speed traveling control process executed by a constant speed traveling control unit of the driving support control unit according to the first embodiment. FIG. 5 is a diagram illustrating a setting example based on accelerator opening and vehicle speed in a constant speed region, an acceleration region, and a deceleration region used in the constant speed traveling control process of FIG. It is a time chart which shows the reduction effect | action of the constant speed area | region by the accelerator depressing operation and the accelerator depressing operation. It is a time chart which shows an example of the target vehicle speed set effect | action which rewrites a target vehicle speed. FIG. 5 is a diagram showing a table in which vehicle speed feedback control and acceleration feedback control used in a constant speed region, an acceleration region, and a deceleration region of the constant speed traveling control process of FIG. 4 are arranged. 5 is a flowchart showing a flow of driving force control processing by vehicle speed feedback control and acceleration feedback control used in the constant speed traveling control processing of FIG. 4. FIG. 10 is a target acceleration setting explanatory diagram illustrating setting of target acceleration on a flat road, a downhill road, and an uphill road when the vehicle is cut at a certain vehicle speed in the acceleration feedback control of the driving force control process of FIG. 9. It is a figure which shows the example of a setting in the acceleration area | region of the acceleration allocation coefficient used when calculating the surplus driving force in the acceleration feedback control of the driving force control process of FIG. FIG. 10 is a map diagram showing an example of an operation line map used when the target driving force is distributed to the engine torque and the engine speed in the driving force control process of FIG. 9. It is a time chart showing the characteristics of accelerator opening, vehicle speed (target vehicle speed), vehicle speed feedback control, and acceleration feedback control in a driving scene that shifts from constant speed → acceleration → constant speed → acceleration → constant speed → deceleration → constant speed. . 7 is a time chart showing characteristics of accelerator opening, vehicle speed (target vehicle speed), vehicle speed feedback control, and acceleration feedback control in a scene where the actual vehicle speed falls below the target vehicle speed during acceleration feedback control in the acceleration region.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the driving assistance control apparatus of the vehicle of this invention is demonstrated based on Example 1 shown in drawing.

  The driving support control device in the first embodiment is applied to an engine vehicle (an example of a vehicle) equipped with a belt-type continuously variable transmission including a torque converter, a forward / reverse switching mechanism, a variator, and a final reduction mechanism. Hereinafter, the configuration of the first embodiment will be described by being divided into “entire system configuration”, “constant speed traveling control system configuration”, “constant speed traveling control processing configuration”, and “driving force control processing configuration”.

[Overall system configuration]
FIG. 1 shows a drive system and a control system of an engine vehicle to which the vehicle driving support control device of the first embodiment is applied. The overall system configuration will be described below with reference to FIG.

As shown in FIG. 1, the drive system of the engine vehicle includes an engine 1, a torque converter 2, a forward / reverse switching mechanism 3, a variator 4, a final reduction mechanism 5, and drive wheels 6 and 6. Yes.
Here, the belt type continuously variable transmission CVT is configured by incorporating the torque converter 2, the forward / reverse switching mechanism 3, the variator 4, and the final reduction mechanism 5 in a transmission case (not shown).

  The engine 1 can control the output torque by an engine control signal from the outside, in addition to the output torque control (normal control) by the accelerator operation by the driver. The engine 1 includes an output torque control actuator 10 that performs torque down control by ignition timing retard control, throttle valve opening / closing operation, and the like.

  The torque converter 2 is a starting element by a fluid coupling having a torque increasing function and a torque fluctuation absorbing function. When the torque increasing function and the torque fluctuation absorbing function are not required, the lockup clutch 20 that can directly connect the engine output shaft 11 (= torque converter input shaft) and the torque converter output shaft 21 is provided. The torque converter 2 includes a pump impeller 23, a turbine runner 24, and a stator 26 provided in a case via a one-way clutch 25.

  The forward / reverse switching mechanism 3 is a mechanism that switches the input rotation direction to the variator 4 between a forward rotation direction during forward travel and a reverse rotation direction during reverse travel. The forward / reverse switching mechanism 3 includes a double pinion planetary gear 30, a forward clutch 31 using a plurality of clutch plates, and a reverse brake 32 using a plurality of brake plates. The forward clutch 31 is hydraulically engaged by the forward clutch pressure Pfc when a forward travel range such as the D range is selected. The reverse brake 32 is hydraulically engaged by the reverse brake pressure Prb when the reverse travel range such as the R range is selected. The forward clutch 31 and the reverse brake 32 are both released by draining the forward clutch pressure Pfc and the reverse brake pressure Prb when the N range (neutral range) is selected.

  The variator 4 has a primary pulley 42, a secondary pulley 43, and a pulley belt 44, and continuously changes the transmission gear ratio (ratio of variator input rotation to variator output rotation) by changing the belt contact diameter. A gear shifting function is provided.

  The primary pulley 42 includes a fixed pulley 42 a and a slide pulley 42 b arranged on the same axis as the variator input shaft 40, and the slide pulley 42 b is slid by the primary pressure Ppri guided to the primary pressure chamber 45.

  The secondary pulley 43 includes a fixed pulley 43 a and a slide pulley 43 b that are arranged coaxially with the variator output shaft 41, and the slide pulley 43 b is slid by the secondary pressure Psec guided to the secondary pressure chamber 46.

  The pulley belt 44 is stretched between a sheave surface that forms a V shape of the primary pulley 42 and a sheave surface that forms a V shape of the secondary pulley 43. The pulley belt 44 is formed of two sets of laminated rings in which a large number of annular rings are stacked from the inside to the outside and a plurality of punched plate members, and is attached by being laminated in an annular manner by being sandwiched along the two sets of laminated rings. It is composed of elements. The pulley belt 44 may be a chain-type belt in which a large number of chain elements arranged in the pulley traveling direction are coupled by pins penetrating in the pulley axial direction.

  The final deceleration mechanism 5 is a mechanism that decelerates the variator output rotation from the variator output shaft 41 and transmits it to the left and right drive wheels 6 and 6 while providing a differential function. The final speed reduction mechanism 5 is a speed reduction gear mechanism that includes an output gear 52 provided on the variator output shaft 41, an idler gear 53 and a reduction gear 54 provided on the idler shaft 50, and a final gear provided on the outer peripheral position of the differential case. And a gear 55. The differential gear mechanism includes a differential gear 56 interposed between the left and right drive shafts 51, 51.

  As shown in FIG. 1, the engine vehicle control system includes a hydraulic control unit 7 that is a hydraulic control system, a CVT control unit 8 that is an electronic control system, an engine control unit 9, and a driving support control unit 14. I have.

  The hydraulic control unit 7 performs primary pressure Ppri guided to the primary pressure chamber 45, secondary pressure Psec guided to the secondary pressure chamber 46, forward clutch pressure Pfc to the forward clutch 31, reverse brake pressure Prb to the reverse brake 32, and the like. It is a unit that regulates pressure. The hydraulic control unit 7 includes an oil pump 70 that is rotationally driven by the driving drive engine 1 and a hydraulic control circuit 71 that adjusts various control pressures based on the discharge pressure from the oil pump 70.

  The hydraulic control circuit 71 includes a line pressure solenoid valve 72, a primary pressure solenoid valve 73, a secondary pressure solenoid valve 74, a select solenoid valve 75, and a lockup pressure solenoid valve 76. Each solenoid valve 72, 73, 74, 75, 76 adjusts to each command pressure by a control command value output from the CVT control unit 8.

  The line pressure solenoid valve 72 adjusts the discharge pressure from the oil pump 70 to the commanded line pressure PL in accordance with the line pressure command value output from the CVT control unit 8. The line pressure PL is a source pressure when adjusting various control pressures, and is a hydraulic pressure that suppresses belt slip and clutch slip against torque transmitted through the drive system.

  The primary pressure solenoid valve 73 adjusts the pressure to the primary pressure Ppri commanded using the line pressure PL as the original pressure in accordance with the primary pressure command value output from the CVT control unit 8. The secondary pressure solenoid valve 74 adjusts the pressure to the secondary pressure Psec commanded using the line pressure PL as the original pressure in accordance with the secondary pressure command value output from the CVT control unit 8.

  The select solenoid valve 75 adjusts the pressure to the forward clutch pressure Pfc or the reverse brake pressure Prb commanded using the line pressure PL as the original pressure according to the forward clutch pressure command value or the reverse brake pressure command value output from the CVT control unit 8. To do.

  The lock-up pressure solenoid valve 76 adjusts the lock-up control pressure PL / U for engaging / slipping / releasing the lock-up clutch 20 according to the lock-up pressure command value output from the CVT control unit 8.

The CVT control unit 8 performs line pressure control, shift control, forward / reverse switching control, lockup control, belt slip protection control, and the like. In the line pressure control, a command value for obtaining a target line pressure corresponding to the throttle opening degree is output to the line pressure solenoid valve 72. In the shift control, when the target gear ratio (target primary rotation Npri ^* ) is determined, a command value for obtaining the determined target gear ratio (target primary rotation Npri ^* ) is output to the primary pressure solenoid valve 73 and the secondary pressure solenoid valve 74. In the forward / reverse switching control, a command value for controlling the engagement / release of the forward clutch 31 and the reverse brake 32 is output to the select solenoid valve 75 according to the selected range position. In the lockup control, a command value for controlling the lockup control pressure PL / U for engaging / slipping / releasing the lockup clutch 20 is output to the lockup pressure solenoid valve 76. In the belt slip protection control, when the pulley belt 44 seems to slip, belt slippage is suppressed by lowering the transmission input torque by torque down control that limits the output torque of the engine 1.

  Information from a primary rotation sensor 80, a vehicle speed sensor 81, a secondary rotation sensor 82, an oil temperature sensor 83, an inhibitor switch 84, a brake switch 85, a turbine rotation sensor 86, and the like is input to the CVT control unit 8. Information from the engine rotation sensor 12 or the like is input to the engine control unit 9. Information from the accelerator opening sensor 87, the constant speed travel selection switch 88, and the like is input to the driving support control unit 14. The constant speed travel selection switch 88 is a switch for selecting a normal travel mode or a constant speed travel mode according to the driver's intention.

  The CVT control unit 8, the engine control unit 9, and the driving support control unit 14 are connected via a CAN communication line 13 so that information can be exchanged.

  FIG. 2 shows an example of the D range continuously variable transmission schedule used when the variator 4 executes the continuously variable transmission control in the automatic transmission mode when the D range is selected.

The “D range shift mode” is an automatic shift mode in which the gear ratio is automatically changed steplessly in accordance with the vehicle operating state. Shift control in the “D range shift mode” is performed by operating points on the D range continuously variable transmission schedule of FIG. 2 specified by the vehicle speed VSP (vehicle speed sensor 81) and the accelerator opening APO (accelerator opening sensor 87) ( VSP, APO) determines the target primary rotational speed Npri ^* . Then, pulley hydraulic pressure control is performed so that the primary rotational speed Npri from the primary rotational sensor 80 matches the target primary rotational speed Npri ^* .

That is, as shown in FIG. 2, the D range continuously variable transmission schedule used in the “D range speed change mode” has a gear ratio range of the lowest gear ratio and the highest gear ratio according to the operating point (VSP, APO). Within the range, the gear ratio is set to change steplessly. For example, when the vehicle speed VSP is constant, if the accelerator depressing operation is performed, the target primary rotational speed Npri ^* increases and shifts in the downshift direction, and if the accelerator depressing operation is performed, the target primary rotational speed Npri ^* decreases. Shift in the upshift direction. When the accelerator opening APO is constant, the vehicle shifts in the upshift direction when the vehicle speed VSP increases, and the vehicle shifts in the downshift direction when the vehicle speed VSP decreases.

[Configuration of constant-speed running control system]
The configuration of the constant speed traveling control system will be described below based on FIG.
As shown in FIG. 3, the hardware configuration of the constant speed traveling control system includes an engine 1 (driving drive source), a belt type continuously variable transmission CVT (continuously variable transmission: torque converter 2, switching mechanism 3, and variator 4). The final reduction mechanism 5) and the drive wheels 6 are provided.

  The torque converter 2 of the belt type continuously variable transmission CVT has a lockup clutch 20 that directly connects the engine output shaft 11 (= torque converter input shaft) and the torque converter output shaft 21 by fastening. The forward / reverse switching mechanism 3 includes a forward clutch 31 that is fastened by selecting a forward travel range (D range, L range, etc.) and a reverse brake 32 that is fastened by selecting a reverse travel range (R range) in parallel. Have. The variator 4 includes a primary pulley 42, a secondary pulley 43, and a pulley belt 44 that spans the pulleys 42 and 43.

  As shown in FIG. 3, the software configuration of the constant speed traveling control system includes a CVT control unit 8 (driving force control means) and an engine control unit 9 (driving drive source control unit: drive) connected by a CAN communication line 13. Force control means) and a driving support control unit 14.

  When the CVT control unit 8 receives a shift request from the driving support control unit 14 via the CAN communication line 13, the CVT control unit 8 prioritizes normal shift control (continuous shift control using the D range continuously variable shift schedule) and supports driving. Corresponding shift control is executed. In the shift control corresponding to the driving support, an upshift or a downshift is performed in which the gear ratio of the variator 4 is set to a target gear ratio according to a gear shift request.

  The engine control unit 9 is a driving force control means for controlling the driving force transmitted from the engine 1 to the driving wheels 6. When a torque down request is input from the driving support control unit 14 via the CAN communication line 13, torque reduction control corresponding to driving support is executed in preference to normal engine control (engine output control according to accelerator opening). . In torque reduction control corresponding to driving support, control is performed to limit the output torque of the engine 1 to a target torque according to a torque reduction request.

  The driving support control unit 14 performs various driving support controls that reduce the burden of driving operations (accelerator operation, brake operation, steering operation, etc.) by the driver, such as automatic brake control and automatic parking control. When the target vehicle speed is set, the driving support control unit 14 includes a constant speed traveling control unit 14a that executes a constant speed traveling mode in which the vehicle speed is maintained by driving force control that matches the actual vehicle speed with the target vehicle speed. Provided.

  The constant speed traveling control unit 14a, when traveling, enters the constant speed region C from the lower threshold value α to the upper threshold value β set in the intermediate accelerator opening region when the accelerator opening amount by the driver's accelerator operation is constant. The actual vehicle speed at the moment of entering the area is set as the target vehicle speed, and the constant speed running mode is started.

  The constant speed traveling control unit 14a includes all accelerator opening areas, a constant speed area C according to the accelerator opening width from the lower threshold value α to the upper threshold value β, an acceleration region A having an opening degree higher than the upper threshold value β, It is divided into a deceleration region B having a lower opening than the side threshold value α. Then, the lower threshold value α and the upper threshold value β are set to higher accelerator opening values as the vehicle speed VSP increases in accordance with the rising gradient of the load / load driving force (hereinafter referred to as “R / L driving force”) due to the vehicle speed increase. It is set (see FIG. 5).

  The constant speed traveling control unit 14a, while executing the constant speed traveling mode, moves the accelerator opening APO to the constant speed region C by the accelerator depressing operation after the accelerator opening APO enters the acceleration region A by the driver's accelerator depressing operation. When entering, the target vehicle speed is rewritten to the actual vehicle speed at the moment of entering the constant speed region C. When the accelerator opening APO enters the deceleration area B by the driver's accelerator depressing operation while the constant speed traveling mode is being executed, the accelerator opening APO enters the constant speed area C by the accelerator depressing operation. The target vehicle speed is rewritten to the actual vehicle speed at the moment of entering C (see FIG. 13).

  The constant speed traveling control unit 14a gradually returns the upper threshold value β to the original value after narrowing the upper threshold value β when the driver performs an accelerator depressing operation while the constant speed traveling mode is being executed. When the accelerator is returned by the driver during the constant speed running mode, the lower threshold value α is narrowed and then gradually returned to the original value (see FIG. 6).

  When the accelerator opening degree APO remains in the constant speed region C during execution of the constant speed traveling mode, the constant speed traveling control unit 14a performs vehicle speed feedback control using a deviation between the target vehicle speed and the actual vehicle speed, and sets the target acceleration to zero. Acceleration feedback control is performed. When the accelerator opening APO enters the acceleration region A by the driver's accelerator depressing operation during execution of the constant speed running mode, acceleration feedback control is performed with the target acceleration as positive. When the accelerator opening APO enters the deceleration region B by the driver's accelerator depressing operation during execution of the constant speed running mode, acceleration feedback control is performed with the target acceleration being negative (see FIG. 13).

  During the acceleration feedback control in the acceleration region A, the constant speed traveling control unit 14a prohibits the vehicle speed feedback control if the actual vehicle speed exceeds the target vehicle speed at that time, and the actual vehicle speed is below the target vehicle speed at that time. Allow vehicle speed feedback control. During acceleration feedback control in the deceleration region B, the vehicle speed feedback control is prohibited if the actual vehicle speed is equal to or lower than the target vehicle speed at that time, and the vehicle speed feedback control is permitted if the actual vehicle speed exceeds the target vehicle speed at that time (see FIG. 8).

  The constant speed traveling control unit 14a estimates the R / L driving force necessary to maintain the vehicle speed VSP with respect to the traveling load resistance. Then, the positive / negative target acceleration used in the acceleration feedback control is calculated based on the excess driving force calculated using the maximum driving force and the zero driving force with reference to the R / L driving force (see FIG. 9).

  The constant speed traveling control unit 14a calculates a target driving force for realizing constant speed traveling control, and converts the target driving force into a target gear ratio and a target torque using an operation line map based on the relationship between the rotation speed of the engine 1 and the torque. To distribute. Then, a shift request for obtaining the target gear ratio allocated to the CVT control unit 8 is output. A torque down request for obtaining the distributed target torque is output to the engine control unit 9 (see FIGS. 3 and 9).

[Constant speed running control processing configuration]
FIG. 4 shows the flow of the constant speed traveling control process executed by the constant speed traveling control unit 14a of the driving support control unit 14 of the first embodiment. Hereinafter, each step of FIG. 4 will be described. In FIG. 4, the vehicle speed is abbreviated as “VSP”, the accelerator opening is “APO”, the vehicle speed feedback control is “vehicle speed F / B”, and the acceleration feedback control is abbreviated as “acceleration F / B”.

  In step S0, following the start, it is determined whether or not the control prohibition condition is not satisfied. If YES (control inhibition condition is not satisfied), the process proceeds to step S1, and if NO (control inhibition condition is satisfied), the process proceeds to return.

  Here, “control inhibition condition established” means when the VDC is activated, when the tire is idling, when the N range is selected, when there is a system abnormality, or the like. Note that “VDC (abbreviation for Vehicle Dynamics Control)” refers to vehicle behavior control in which the behavior of the vehicle is controlled by braking force control or driving force control of each wheel.

  In step S1, following the determination that the control prohibition condition is not satisfied in step S0, it is determined whether or not the vehicle speed VSP is in a control vehicle speed region in which constant speed traveling control is permitted. If YES (VSP is in the controlled vehicle speed range), the process proceeds to step S2, and if NO (VSP is out of the controlled vehicle speed range), the process proceeds to return.

  Here, the information of “vehicle speed VSP” is acquired from the vehicle speed sensor value from the vehicle speed sensor 81. The “control vehicle speed range” refers to a vehicle speed range that is set in advance as a control target vehicle speed range that permits constant speed travel control. As shown in the biaxial coordinate plane of the vehicle speed axis and the accelerator opening axis in FIG. 5, the control vehicle speed range is from the first vehicle speed VSP1 (for example, about 40 km / h) to the second vehicle speed VSP2 (for example, about 100 km / h). ).

  In step S2, following the determination that the VSP in step S1 is within the control vehicle speed range, it is determined whether or not the accelerator opening APO is higher than the lower threshold value α and lower than the upper threshold value β. If YES (APO is in the constant speed region), the process proceeds to step S3. If NO (APO is outside the constant speed area), the process proceeds to step S9.

  Here, the information of the “accelerator opening APO” is acquired from the accelerator opening sensor value from the accelerator opening sensor 87. The “constant speed region” refers to an intermediate accelerator opening range (for example, an opening range of 10% to 20%) determined in advance according to the vehicle speed VSP as an accelerator opening region for maintaining constant speed travel.

  As shown in the biaxial coordinate plane of the vehicle speed axis and the accelerator opening axis in FIG. 5, the constant speed region C shows the characteristic line of the lower threshold value α and the upper threshold value β. A higher accelerator opening value is set as the vehicle speed VSP increases in accordance with the gradient. Then, a constant speed region C with an accelerator opening width that expands as the vehicle speed VSP increases from the lower threshold value α to the upper threshold value β, an acceleration region A that has a higher opening than the upper threshold value β, It is divided into a deceleration region B having a lower opening than the lower threshold value α. Therefore, if the vehicle speed VSP is cut in the direction of the accelerator opening, the lower threshold value α and the upper threshold value β are determined, and if the lower threshold value α <the accelerator opening APO <the upper threshold value β, the accelerator opening APO is determined. It is determined that it exists in the speed region C.

  Further, the upper threshold value β is gradually returned to the original value after the upper threshold value β is narrowed as shown in FIG. 6 when the accelerator is further depressed by the driver during the constant speed running mode. . The lower threshold value α is gradually returned to the lower threshold value α after the lower threshold value α is narrowed when the driver depresses the accelerator while the constant speed running mode is being executed.

In step S3, following the determination that APO is in the constant speed region in step S2, the vehicle speed VSP at that time (= actual vehicle speed by the vehicle speed sensor 81) is set to the target vehicle speed VSP ^*, and the set target vehicle speed VSP is set. ^The constant speed running mode for maintaining ^* is executed, and the process proceeds to step S4.

  In step S4, following execution of the constant speed travel mode in step S3, it is determined whether or not it is the initial constant speed travel mode. If YES (first constant speed running mode), the process proceeds to step S5. If NO (constant speed running mode other than the first time), the process proceeds to step S6.

In step S5, following the determination in step S4 that the vehicle is in the initial constant speed travel mode, the current vehicle speed VSP, which is the actual vehicle speed at the moment of entering the constant speed region C, is set to the target vehicle speed VSP ^* , and the process proceeds to step S6. move on.

  In step S6, following the determination of the target vehicle speed set in step S5 or the constant speed running mode other than the initial in step S4, the vehicle speed F / B is performed, and the process proceeds to step S7.

Here, “vehicle speed F / B” refers to vehicle speed feedback control for increasing / decreasing the driving force so as to eliminate the vehicle speed deviation between the target vehicle speed VSP ^* and the actual vehicle speed VSP.
“Vehicle speed F / B” is, for example, PID control (P: proportional, I: integral, D: derivative).

  In step S7, following the determination of vehicle speed F / B in S6, S14, and S19 or NO in S13 and S18, acceleration F / B is performed, and the process proceeds to return.

Here, “acceleration F / B” refers to acceleration feedback control for increasing / decreasing the driving force so as to eliminate the acceleration deviation between the target acceleration dV / dt ^* and the actual acceleration dV / dt.
The “acceleration F / B” is performed in the entire accelerator opening range, for example, PI control.

  In step S9, following the determination that APO is outside the constant speed region in step S2, it is determined whether or not the accelerator opening APO is equal to or lower than the lower threshold value α. If YES (accelerator opening APO ≦ α), the process proceeds to step S10, and if NO (accelerator opening APO> α), the process proceeds to step S15.

  In step S10, following the determination that accelerator opening APO ≦ α in step S9, a deceleration mode that allows a decrease in vehicle speed VSP is executed, and the process proceeds to step S11.

  In step S11, following execution of the deceleration mode in step S10, it is determined whether or not it is the previous acceleration mode. If YES (the previous acceleration mode), the process proceeds to step S12. If NO (not the previous acceleration mode), the process proceeds to step S13.

In step S12, following the determination of the previous acceleration mode in step S11, the current vehicle speed VSP, which is the actual vehicle speed at the moment when the vehicle enters the constant speed region C from the deceleration region B, is set to the target vehicle speed VSP ^*. Proceed to S13.

In step S13, it is determined that it is not the previous acceleration mode in step S11, or it is determined whether the vehicle speed VSP exceeds the current target vehicle speed VSP ^* following the target vehicle speed set in step S12. If YES (vehicle speed VSP> target vehicle speed VSP ^* ), the process proceeds to step S14. If NO (vehicle speed VSP ≦ target vehicle speed VSP ^* ), the process proceeds to step S7.

In step S14, following the determination that vehicle speed VSP> target vehicle speed VSP ^* in step S13, vehicle speed F / B is performed, and the process proceeds to step S7.

  In step S15, following the determination that accelerator opening APO> α in step S9, an acceleration mode that allows the vehicle speed VSP to increase is executed, and the process proceeds to step S16.

  In step S16, following execution of the acceleration mode in step S15, it is determined whether or not it is the previous deceleration mode. If YES (the previous deceleration mode), the process proceeds to step S17, and if NO (not the previous deceleration mode), the process proceeds to step S18.

In step S17, following the determination of the previous deceleration mode in step S16, the current vehicle speed VSP, which is the actual vehicle speed at the moment of entering the constant speed region C from the acceleration region A, is set to the target vehicle speed VSP ^*. Proceed to S18.

Here, the target vehicle speed VSP ^* set at step S12 and S17, as shown in FIG. 7, and sets the target vehicle speed VSP ^* with the accelerator opening APO and the lower threshold α and the upper threshold value beta (target Vehicle speed set points P1 to P4). That is, not only the vehicle speed VSP at the moment when the accelerator opening APO enters the constant speed region C of the intermediate opening range (α <APO <β), but also the immediate release of the accelerator opening APO and the immediate depression of the accelerator opening APO Considering this, the edge is kept at an edge that is equal to or lower than the upper threshold value β or equal to or higher than the lower threshold value α. That is, it is not necessarily within the predetermined range.

In step S18, it is determined that it is not the previous deceleration mode in step S16, or it is determined whether the vehicle speed VSP is equal to or lower than the current target vehicle speed VSP ^* following the target vehicle speed set in step S17. If YES (vehicle speed VSP ≦ target vehicle speed VSP ^* ), the process proceeds to step S19. If NO (vehicle speed VSP> target vehicle speed VSP ^* ), the process proceeds to step S7.

In step S19, following determination that vehicle speed VSP ≦ target vehicle speed VSP ^* in step S18, vehicle speed F / B is performed, and the process proceeds to step S7.

  Here, when the use of the vehicle speed F / B and the acceleration F / B in the constant speed traveling control process is arranged, it is as shown in FIG. That is, the vehicle speed F / B is permitted in the constant speed region C while the acceleration F / B is always performed in the constant speed region C, the acceleration region A, and the deceleration region B. However, the vehicle speed F / B is additionally applied when decelerating despite the accelerator depressing operation, and the vehicle speed F / B is additionally applied when accelerating despite the accelerator depressing operation. .

[Driving force control processing configuration]
FIG. 9 shows a flow of driving force control processing by vehicle speed feedback control (vehicle speed F / B) and acceleration feedback control (acceleration F / B) used in the constant speed traveling control processing of FIG. Hereinafter, each step of FIG. 9 will be described.

  In step S21, following the start, an R / L driving force Fo that is a driving force necessary to maintain a constant vehicle speed regardless of the travel load resistance is estimated, and the process proceeds to step S22.

Here, the “R / L driving force Fo” is a reference driving force of the target driving force F ^* in the acceleration region A and the deceleration region B as shown in FIG. Can be estimated by the following equation (2).
m · dV / dt = F−RL (1)
RL = F−m · dV / dt (2)
However, m: vehicle weight, dV / dt: acceleration, F: driving force, RL: various disturbance driving forces such as running resistance.
That is, the R / L driving force Fo is the driving force F (R / L opening) at the R / L accelerator opening maintaining the constant speed (dV / dt = 0),
Fo = F (R / L opening) = Te x gear ratio x final gear ratio / tire diameter (3)
Te: Calculated by equation (3) based on engine torque at the R / L accelerator opening. The final R / L driving force Fo is filtered by a first-order lag calculation or the like for the purpose of noise removal or the like.

  In step S22, following the estimation of the R / L driving force Fo in step S21, an excess driving force based on the R / L driving force Fo is calculated, and the process proceeds to step S23.

  Here, the surplus driving force is calculated by multiplying a driving force difference based on the R / L driving force Fo and an allocation coefficient. For example, the surplus driving force in the acceleration region A shown in FIG. 10 is an acceleration region division factor in which the fully opened opening (8/8 opening) is 1 and the R / L opening is zero by the accelerator opening APO at that time. Ask for. Then, the acceleration allocation coefficient is determined from the acceleration area division coefficient using the acceleration allocation coefficient characteristics (flat, downhill, uphill) in which the MAX driving force when the accelerator is fully opened and the R / L driving force are 0 shown in FIG. . Then, it is calculated by multiplying the driving force difference (= MAX driving force-R / L driving force) by the determined acceleration allocation coefficient. The surplus driving force in the deceleration region B is similarly calculated using the driving force difference (= R / L driving force−MIN driving force).

In step S23, following the calculation of the surplus driving force in step S22, the target acceleration dV / dt ^* is calculated based on the surplus driving force, and the process proceeds to step S24.
Here, "target acceleration dV / dt ^* " is
dV / dt ^* = surplus driving force ÷ vehicle weight (4)
(4) is calculated.

In step S24, following the calculation of the target acceleration dV / dt ^* in step 23, it is determined whether or not the vehicle speed F / B is permitted. If YES (vehicle speed F / B permitted), the process proceeds to step S25, and if NO (vehicle speed F / B prohibited), the process proceeds to step S26.

In step S25, following the determination that the vehicle speed F / B is permitted in step S24, the target is determined by the surplus driving force, the corrected driving force corresponding to the vehicle speed F / B, and the corrected driving force corresponding to the acceleration F / B in step S22. The driving force F ^* is calculated, and the process proceeds to step S27.

Here, the corrected driving force for the vehicle speed F / B refers to a driving force obtained by PID control corresponding to the vehicle speed deviation between the target vehicle speed VSP ^* and the actual vehicle speed VSP. The corrected driving force corresponding to the acceleration F / B is a driving force obtained by PI control according to the acceleration deviation between the target acceleration dV / dt ^* and the actual acceleration dV / dt.

In step S26, following the determination that the vehicle speed F / B is prohibited in step S24, the target driving force F ^* is calculated from the excess driving force and the corrected driving force corresponding to the acceleration F / B in step S22, and step S27. Proceed to

  Here, in the judgment in step S24, the vehicle speed F / B permission → vehicle speed F / B prohibition, or the vehicle speed F / B prohibition → vehicle speed F / B permission transition period, the transition of the vehicle speed F / B is connected. Linear correction is performed with a permission coefficient of 0 to 1 to avoid sudden changes in the operation amount. That is, PD multiplies the manipulated variable by a permission coefficient, and I multiplies the deviation before the component by a permission coefficient to smoothly connect / disallow vehicle speed F / B.

In step S27, the target driving force F ^* is filtered following the calculation of the target driving force F ^* in step S25 or step S26, and the process proceeds to step S28.

Here, the filtering of the target driving force F ^* is operated in a region where the power train eigenvalue is sufficiently cut. The reason is that it is desired to avoid inducing vibration (resonance) of the power train eigenvalue by operating the driving force.

In step S28, following the filtering of the target driving force in step S27, the operating point (Ne, Nt) for allocating the target driving force F ^* to the target gear ratio and the target torque using the operation line map shown in FIG. And proceeds to step S28.

Here, when the target driving force F ^* is calculated, by using the operation line map shown in FIG. 12, the engine speed Ne and the engine torque, which are operating points, are determined by the intersection of the target driving force F ^* and the operation line. Nt is determined. In addition, the operation line shown in FIG. 12 is set by fuel consumption performance or the like.

  In step S29, following the determination of the operating point in step S28, a target speed ratio of the variator 4 is set from the engine speed Ne, and a speed ratio request for setting the speed ratio of the variator 4 to the target speed ratio is made to the CVT control unit 8. And proceeds to step S30.

  Here, the target speed ratio is determined by using the engine speed Ne based on the operation line map as the variator input speed. Then, the target gear ratio is set by setting the secondary rotational speed Nsec at that time as the variator output rotational speed. Then, the set target gear ratio is filtered so as not to fluctuate. The reason for deciding the target gear ratio earlier than the target torque is that the engine torque has a faster response speed than the gear ratio, and if the gear ratio is finely moved, rotation changes frequently occur, and there is a possibility that a sense of incongruity appears. Due to the high price.

  In step S30, following the output of the gear ratio request to the CVT control unit 8 in step S29, a torque-down request for setting the output torque of the engine 1 as the target torque is output to the engine control unit 9, and the process proceeds to return.

Here, the target torque is calculated from the target driving force F ^* and the gear ratio of the variator 4 at that time, and a torque down request is output using the target torque as a limit torque. At this time, it is only necessary to be able to perform full torque control, but in the first embodiment, it is realized only by torque down control. For this reason, the accelerator opening range in the constant speed region C is set to a higher accelerator opening in advance and the engine torque can be output, and torque control is performed with the engine torque suppressed by torque reduction.

  Next, the operation of the first embodiment is divided into “existing constant speed traveling control technology”, “constant speed traveling control processing operation”, “driving force control processing operation”, and “constant speed traveling control operation by one pedal operation”. explain.

[Existing constant speed travel control technology]
A cruise control system (sometimes called "ASCD" or "Auto-Cruise System") is known as an existing technology that demonstrates a constant-speed running control function that maintains a set speed without depressing the accelerator pedal. It has been.

  When the cruise control system is used, the vehicle can travel without stepping on the accelerator pedal (for example, a vehicle speed of 40 km / h to 100 km / h), which contributes to reducing driver fatigue and improving passenger comfort. However, in order to use the cruise control system, troublesome switch operation by the driver described below is required.

  First, when operating the cruise control system, press the main switch to turn it on. When setting the target vehicle speed, accelerate to the desired vehicle speed, press the set switch briefly to display the set indicator on the display, release the accelerator pedal to start the constant speed running mode, and the target vehicle speed will be Maintained. When overtaking, the accelerator pedal is depressed. After depressing the accelerator pedal, when the foot is released from the accelerator pedal, the vehicle speed returns to the target vehicle speed.

To stop the cruise control system, do one of the following: 1. Press the cancel switch.
2. Press the brake pedal lightly while pressing the set switch.
3. Turn off the main switch.

  When the vehicle speed is lower than the minimum vehicle speed, when the actual vehicle speed is lower than the set vehicle speed, when the VDC is activated, when the tire is idle, when the N range is selected, or when there is a system abnormality The cruise control system automatically stops operating.

To increase the target vehicle speed, perform any of the following operations.
・ Depress the accelerator pedal and press the set switch briefly when the desired vehicle speed is reached.
・ Press and hold the resume / accelerate switch and release the switch when the desired vehicle speed is reached.
・ Press the resume / accelerate switch briefly to set the desired vehicle speed. Each time the switch is pressed, the target vehicle speed increases by about 1.0 km / h.

To lower the target vehicle speed, perform any of the following operations.
・ Press the brake pedal lightly and when the desired speed is reached, press the set switch briefly.
・ Press and hold the set switch, and release the switch when it decelerates to the desired speed.
・ Press the set switch briefly to set the desired speed. Each time the switch is pressed, the target vehicle speed decreases by about 1.0 km / h.

[Constant speed running control processing action]
The first embodiment aims to intuitively carry out the above-described operation by operating only the accelerator pedal. Hereinafter, the constant speed traveling control process operation will be described based on the flowchart of FIG.

When the vehicle speed VSP is a control vehicle speed region in which constant speed traveling control is permitted and the accelerator opening APO exceeds the lower threshold value α and enters the constant speed region C by the accelerator depression operation, in the flowchart of FIG. The process proceeds from S0, S1, S2, S3, S4, and S5. In S5, the vehicle speed VSP at the moment of entering the constant speed region C (the actual vehicle speed by a vehicle speed sensor 81) is set to the target vehicle speed VSP ^*, to maintain the set target vehicle speed VSP ^* "constant-speed travel mode" is started The

If the accelerator opening APO remains in the constant speed region C after the start of the constant speed travel mode, the flow of going from S2, S3, S4, S6, and S7 is repeated. In S6, the vehicle speed F / B using the target vehicle speed VSP ^* set in S5 is permitted, and in S7, the acceleration F / B with target acceleration = 0 is executed.

During execution of the constant speed travel mode, if the accelerator opening APO is equal to or greater than the upper threshold value β, enters the acceleration area A from the constant speed area C, and the actual vehicle speed VSP> target vehicle speed VSP ^* , S2 to S9 → S15 → S16. → S18 → S7. That is, the vehicle speed F / B using the target vehicle speed VSP ^* is prohibited, and the acceleration F / B with the target acceleration> 0 is executed.

Present in the accelerator opening APO acceleration region A, the transition from the actual vehicle speed VSP> target vehicle speed VSP ^* to the actual vehicle speed VSP ≦ target vehicle speed VSP ^*, proceeds from S18 to S19 → S7. In S19, the vehicle speed F / B using the target vehicle speed VSP ^* at that time is permitted, and the acceleration F / B with the target acceleration> 0 is executed.

When entering the constant speed region C from the acceleration region A by the accelerator depressing operation, the process proceeds from S2 → S3 → S4 → S5 → S6 → S7. In S6, the vehicle speed F / B using the target vehicle speed VSP ^* set in S5 is permitted, and in S7, the acceleration F / B with target acceleration = 0 is executed.

During execution of the constant speed travel mode, if the accelerator opening APO becomes lower than the lower threshold value α, enters the deceleration area B from the constant speed area C, and if the actual vehicle speed VSP ≦ target vehicle speed VSP ^* , S2 to S9 → S10 → The process proceeds from S11 to S13 to S7. That is, the vehicle speed F / B using the target vehicle speed VSP ^* is prohibited, and the acceleration F / B with the target acceleration <0 is executed.

Accelerator opening APO exists in the deceleration region B, and the transition from the actual vehicle speed VSP ≦ target vehicle speed VSP ^* to the actual vehicle speed VSP> target vehicle speed VSP ^*, proceeds from steps S13 to S14 → S7. In S14, the vehicle speed F / B using the target vehicle speed VSP ^* at that time is permitted, and the acceleration F / B at the target acceleration <0 is executed.

When entering the constant speed region C from the deceleration region B by the accelerator depressing operation, the process proceeds from S 2 → S 3 → S 4 → S 5 → S 6 → S 7. In S6, the vehicle speed F / B using the target vehicle speed VSP ^* set in S5 is permitted, and in S7, the acceleration F / B with target acceleration = 0 is executed.

As described above, in the constant speed traveling control process, when the accelerator opening APO enters the constant speed region C by the accelerator depressing operation while the vehicle speed VSP is traveling in the controlled vehicle speed region, the actual vehicle speed at the moment of entering the constant speed region C is obtained. VSP is set to the target vehicle speed VSP ^* . Then, the “constant speed running mode” for maintaining the set target vehicle speed VSP ^* is started.

In the constant speed traveling control process, when the target vehicle speed VSP ^* is increased, the accelerator opening APO enters the acceleration region A by the accelerator depression operation. Thereafter, when the vehicle enters the constant speed region C from the acceleration region A by the accelerator depressing operation, the actual vehicle speed VSP at the moment of entering the constant speed region C is rewritten to the target vehicle speed VSP ^* .

In the constant speed traveling control process, when the target vehicle speed VSP ^* is lowered, the accelerator opening APO enters the deceleration region B by the accelerator depressing operation. Thereafter, when the vehicle enters the constant speed region C from the deceleration region B by depressing the accelerator, the actual vehicle speed VSP at the time of entering the constant speed region C is rewritten to the target vehicle speed VSP ^* .

In the constant speed traveling control process, when the vehicle is in the acceleration region A by depressing the accelerator, in principle, the vehicle speed F / B is prohibited and the acceleration F / B with the target acceleration> 0 is executed. However, if the vehicle speed is lower than the target vehicle speed VSP ^* set immediately before when climbing up while in the acceleration region A, the vehicle speed F / B is restarted and at least does not fall below the target vehicle speed VSP ^* set immediately before. To be done.

In the constant speed traveling control process, when the vehicle is in the deceleration region B by the accelerator depressing operation, in principle, the vehicle speed F / B is prohibited and the acceleration F / B with the target acceleration <0 is executed. However, if the vehicle is accelerating faster than the target vehicle speed VSP ^* set immediately before on a downhill or the like while in the deceleration area B, the vehicle speed F / B is restarted and at least exceeds the target vehicle speed VSP ^* set immediately before Not to be.

[Driving force control processing action]
Hereinafter, the operation of the driving force control process will be described based on the flowchart shown in FIG.
When the vehicle speed F / B is permitted, the flow of S21 → S22 → S23 → S24 → S25 → S27 → S28 → S29 → S30 is repeated in the flowchart of FIG.
In S21, the R / L driving force Fo is estimated. In S22, a surplus driving force based on the R / L driving force Fo is calculated. In step S23, the target acceleration dV / dt ^* is calculated based on the surplus driving force. Calculated.

Following the determination that the vehicle speed F / B is permitted in S24, in S25, the target driving force is determined by the surplus driving force, the corrected driving force for the vehicle speed F / B, and the corrected driving force for the acceleration F / B in step S22. F ^* is calculated. In S27, the target driving force F ^* is filtered, and in S28, an operating point for allocating the target driving force F ^* to the gear ratio and the engine torque is determined. In S29, a gear ratio request for setting the gear ratio of the variator 4 as the target gear ratio is output to the CVT control unit 8, and in S30, a torque down request for setting the output torque of the engine 1 as the target torque is issued to the engine control unit 9. Is output.

When the vehicle speed F / B is prohibited, the flow of S21 → S22 → S23 → S24 → S26 → S27 → S28 → S29 → S30 is repeated in the flowchart of FIG.
In S26 following the determination that the vehicle speed F / B is prohibited in S24, the target driving force F ^* is calculated from the surplus driving force and the corrected driving force corresponding to the acceleration F / B in step S22.

  In the judgment at S24, when the vehicle speed F / B permission → vehicle speed F / B prohibition or the vehicle speed F / B prohibition → vehicle speed F / B permission shifts, the vehicle speed F / B connection is permitted from 0 to 1. Linearly corrected by the coefficient.

As described above, in the driving force control process, the target driving force F ^* for realizing the constant speed traveling control is calculated based on the vehicle speed F / B / acceleration F / B. When the target driving force F ^* is calculated, the target driving force F ^* is distributed to the target gear ratio and the target torque using an operation line map based on the relationship between the rotational speed Ne of the engine 1 and the torque Nt. Then, a shift request for obtaining the allocated target gear ratio is output to the CVT control unit 8. A torque down request for obtaining the distributed target torque is output to the engine control unit 9.

  In the driving force control process, when the permitted region of the vehicle speed F / B and the prohibited region of the vehicle speed F / B are connected to each other, the two regions can be smoothly connected by avoiding a sudden change in the driving force manipulated variable by linear interpolation.

[Constant speed control by one pedal operation]
FIG. 13 shows each characteristic in a traveling scene where constant speed → acceleration → constant speed → acceleration → constant speed → deceleration → constant speed. FIG. 14 shows each characteristic in a scene where the actual vehicle speed falls below the target vehicle speed during acceleration feedback control in the acceleration region. Hereinafter, the constant speed traveling control action by the one pedal operation will be described based on FIG. 13 and FIG.

  By time t1 in FIG. 13, the accelerator opening APO enters the constant speed region C by the accelerator depressing operation, the vehicle speed VSP at the moment of entering the constant speed region C is set to the target vehicle speed 1, and the set target vehicle speed 1 is set. It is assumed that the “constant speed running mode” to be maintained is started.

  When the accelerator opening APO enters the acceleration area A from the constant speed area C by depressing the accelerator at time t1, the vehicle speed F / B smoothly transitions from ON to OFF until time t1, and the acceleration F / B is Transition from G = 0 until t1 to G> 0. With this acceleration F / B, the vehicle speed VSP increases from the vehicle speed at time t1 (≈target vehicle speed 1) according to the driver's acceleration request.

  When the accelerator opening APO enters the constant speed region C from the acceleration region A by the accelerator depressing operation at time t2, first, the target vehicle speed 2 at the moment when the target vehicle speed enters the constant speed region C from the target vehicle speed 1 (> The target vehicle speed is rewritten to 1). At the same time, the vehicle speed F / B smoothly shifts from OFF to ON until time t2, and the acceleration F / B shifts from G> 0 to G = 0 until time t2. The vehicle speed F / B is controlled so that the vehicle speed VSP maintains the vehicle speed at the time t2 (= target vehicle speed 2) as it is.

  When the accelerator opening APO enters the acceleration region A from the constant speed region C by depressing the accelerator at time t3, the vehicle speed F / B smoothly transitions from ON to OFF until time t3, and the acceleration F / B is Transition from G = 0 until t3 to G> 0. With this acceleration F / B, the vehicle speed VSP increases from the vehicle speed at time t3 (≈target vehicle speed 2) according to the driver's acceleration request.

  When the accelerator opening APO enters the constant speed region C from the acceleration region A by the accelerator depressing operation at time t4, first, the target vehicle speed 3 at the moment when the target vehicle speed enters the constant speed region C from the target vehicle speed 2 (> The target vehicle speed is rewritten to 2). At the same time, the vehicle speed F / B smoothly transitions from OFF to ON until time t4, and the acceleration F / B shifts from G> 0 to G = 0 until time t4. By this vehicle speed F / B, the vehicle speed VSP is controlled so as to maintain the vehicle speed at the time t4 (= target vehicle speed 3).

  When the accelerator opening APO enters the deceleration region B from the constant speed region C by the accelerator depressing operation at time t5, the vehicle speed F / B smoothly transitions from ON to OFF until time t5, and the acceleration F / B is Transition from G = 0 to G <0 until time t5. With this acceleration F / B, the vehicle speed VSP decreases from the vehicle speed at time t5 (≈target vehicle speed 3) according to the driver's deceleration request.

  When the accelerator opening APO enters the constant speed region C from the deceleration region B by the accelerator depression operation at time t6, first, the target vehicle speed 4 at the moment when the target vehicle speed enters the constant speed region C from the target vehicle speed 3 (<target Rewritten to vehicle speed 3). At the same time, the vehicle speed F / B smoothly shifts from OFF to ON until time t6, and the acceleration F / B shifts from G <0 to G = 0 until time t6. By this vehicle speed F / B, the vehicle speed VSP is controlled to maintain the vehicle speed at the time t6 (= target vehicle speed 4) as it is.

Thus, the target vehicle speed VSP ^* is set by the accelerator depressing operation that enters the constant speed region of the accelerator opening APO, and the constant speed traveling mode is started. Rewriting the target vehicle speed VSP ^* to increase the target vehicle speed VSP ^* is performed by performing an accelerator return operation at the timing when the vehicle speed desired by the driver is reached during the accelerator depression operation. Further, the rewriting of the target vehicle speed to lower the target vehicle speed VSP ^* is performed by performing the accelerator stepping operation at the timing when the vehicle speed desired by the driver is reached during the accelerator stepping back operation. That is, not only can the target vehicle speed VSP ^{* at} which the constant speed traveling mode is started be set by a one-pedal operation on the accelerator pedal, but the target vehicle speed VSP ^* can be appropriately changed.

  A scene in which the actual vehicle speed is lower than the target vehicle speed due to an increase in traveling load due to traveling on an uphill road during acceleration feedback control in the acceleration region will be described with reference to FIG.

  When the accelerator opening APO enters the acceleration area A from the constant speed area C by depressing the accelerator at time t1, the vehicle speed F / B smoothly transitions from ON to OFF until time t1, and the acceleration F / B is Transition from G = 0 until t1 to G> 0. Due to this acceleration F / B, the vehicle speed VSP increases from the vehicle speed at time t1 (≈target vehicle speed) according to the driver's acceleration request, but when entering an uphill road on the way, deceleration starts due to an increase in travel load. .

  After starting deceleration, when the vehicle speed VSP falls below the target vehicle speed at time t2, the vehicle speed F / B smoothly transitions from OFF to ON until time t2, and the vehicle speed VSP decreases due to the restart of the vehicle speed F / B. It can be suppressed. Then, when the vehicle speed VSP exceeds the target vehicle speed at time t3 after passing through an uphill road or the like, the vehicle speed F / B smoothly transitions from ON to OFF until time t3. For this reason, the vehicle speed VSP increases from the vehicle speed at time t3 (≈target vehicle speed) according to the driver's acceleration request due to the acceleration F / B when G> 0.

  Thus, when deceleration intervenes during acceleration F / B in the acceleration region, the vehicle speed F / B is resumed while maintaining the acceleration F / B at G> 0. By resuming the vehicle speed F / B, the driving force is controlled so that it does not fall below the target vehicle speed that was set immediately before. can do.

  As described above, in the vehicle driving support control apparatus of the first embodiment, the effects listed below can be obtained.

(1) Driving force control means (CVT control unit 8, engine control unit 9) for controlling the driving force transmitted from the driving source for driving (engine 1) to the driving wheel 6, and driving for reducing the driving operation burden on the driver. Driving support control means (driving support control unit 14) for performing support control.
A drive assistance control means (driving support control unit 14), the target vehicle speed VSP ^* is set, the driving force control for matching the actual vehicle speed VSP to target vehicle speed VSP ^* a constant speed running mode in which the vehicle travels while maintaining the vehicle speed A constant speed traveling control unit 14a to be executed is provided.
When the accelerator opening APO by the driver's accelerator operation enters the constant speed region C from the lower threshold value α to the upper threshold value β set in the intermediate accelerator opening region during traveling, the constant speed traveling control unit 14a The actual vehicle speed VSP when entering the speed region C is set to the target vehicle speed VSP ^* , and the constant speed running mode is started (FIG. 4).
Thus, by giving the start condition of the constant speed traveling mode according to the accelerator operation condition of the driver, it is possible to enter the constant speed traveling mode by one pedal operation even when the vehicle speed is not stable during traveling. Although it is not possible to maintain the constant speed driving mode without stepping on the accelerator pedal as in the existing cruise control system, the burden of fine accelerator adjustment operations performed by the driver to maintain the vehicle speed while driving is reduced. it can.

(2) The constant speed traveling control unit 14a divides all accelerator opening areas into a constant speed area C based on the accelerator opening width from the lower threshold value α to the upper threshold value β, and an acceleration area A higher than the upper threshold value β. And a deceleration region B having a lower opening than the lower threshold value α.
The lower threshold value α and the upper threshold value β are set to higher accelerator opening values as the vehicle speed VSP increases in accordance with the rising gradient of the load / load driving force (R / L driving force) due to the vehicle speed increase (FIG. 5).
In this way, by setting the constant speed region C along the road / load driving force (R / L driving force), the vehicle speed VSP during traveling is constant according to whether it is a low speed region or a high speed region. An appropriate target vehicle speed VSP ^* that can maintain the driving mode can be set.

(3) During the execution of the constant speed running mode, the constant speed running control unit 14a, after the accelerator opening APO enters the acceleration region A by the driver's accelerator depressing operation, the accelerator opening APO is kept at the constant speed by the accelerator depressing operation. When entering the region C, the target vehicle speed VSP ^* is rewritten to the actual vehicle speed VSP when entering the constant speed region C.
When the accelerator opening APO enters the deceleration region B by the driver's accelerator depressing operation while the constant speed traveling mode is being executed, the accelerator opening APO enters the constant speed region C by the accelerator depressing operation. The target vehicle speed VSP ^* is rewritten to the actual vehicle speed VSP when entering (FIG. 11).
In this way, by rewriting the target vehicle speed VSP ^* by changing the driver's accelerator operation, the target set by the one-pedal operation in accordance with the driver's acceleration / deceleration request during driving in the constant speed driving mode. The vehicle speed VSP ^* can be rewritten.

(4) The constant speed traveling control unit 14a gradually returns the upper threshold value β to the original value after narrowing the upper threshold value β when the driver performs an accelerator depressing operation while the constant speed traveling mode is being executed.
When the accelerator is returned by the driver during the constant speed running mode, the lower threshold value α is gradually reduced and then gradually returned to the original value.
In this way, by performing the control to narrow down the constant speed region C by the accelerator opening width by the driver's accelerator depressing and stepping back operation, the rewriting of the set target vehicle speed VSP ^* matches the driver's intention by the accelerator operation. Can be encouraged.

(5) If the accelerator opening degree APO remains in the constant speed region C during execution of the constant speed traveling mode, the constant speed traveling control unit 14a uses the deviation between the target vehicle speed VSP ^* and the actual vehicle speed VSP. (Vehicle speed F / B) and acceleration feedback control (acceleration F / B) with the target acceleration α ^* being zero are performed.
When the accelerator opening APO enters the acceleration region A by the driver's accelerator depressing operation during execution of the constant speed running mode, acceleration feedback control (acceleration F / B) with the target acceleration α ^* as positive is performed.
When the accelerator opening APO enters the deceleration region B by the driver's accelerator depressing operation during the constant speed running mode, acceleration feedback control (acceleration F / B) is performed with the target acceleration α ^* as negative (Fig. 6). .
Thus, acceleration performance after entering the acceleration region A from the constant speed region C during traveling in the constant speed traveling mode by performing acceleration feedback control (acceleration F / B) in the acceleration region A and the deceleration region B. And the deceleration performance after entering the deceleration area B from the constant speed area C can be ensured.

(6) During the acceleration feedback control in the acceleration region A, the constant speed traveling control unit 14a prohibits the vehicle speed feedback control (vehicle speed F / B) if the actual vehicle speed VSP exceeds the target vehicle speed VSP ^* at that time. Vehicle speed feedback control (vehicle speed F / B) is permitted if the actual vehicle speed VSP is equal to or less than the target vehicle speed VSP ^{* at} that time.
During acceleration feedback control in the deceleration area B, if the actual vehicle speed VSP is less than or equal to the current target vehicle speed VSP ^* , the vehicle speed feedback control (vehicle speed F / B) is prohibited, and the actual vehicle speed VSP determines the target vehicle speed VSP ^* at that time. If it exceeds, vehicle speed feedback control (vehicle speed F / B) is permitted (FIG. 6).
In this way, by allowing the vehicle speed feedback control (vehicle speed F / B) for the deceleration in the acceleration region A and the acceleration in the deceleration region B, the return response from the deceleration state to the acceleration state in the acceleration region A The return response from the acceleration state to the deceleration state in the deceleration region B can be increased.

(7) The constant speed traveling control unit 14a estimates the load / load driving force (R / L driving force) necessary to maintain the vehicle speed VSP with respect to the traveling load resistance.
The surplus that is calculated using the maximum and zero driving forces based on the load / load driving force (R / L driving force) with the positive / negative target acceleration α ^* used in acceleration feedback control (acceleration F / B) Calculation is based on the driving force (FIG. 7).
In this way, the target acceleration α ^* is calculated based on the load / load driving force (R / L driving force) based on the surplus driving force as a reference, so that the driving force in the acceleration region A and the deceleration region B can be reduced. Suppressed and appropriate driving force control can be performed.

(8) As drive force control means, CVT control means (CVT control unit 8) for controlling the gear ratio of a continuously variable transmission (belt type continuously variable transmission CVT) mounted in the drive system; And a travel drive source control means (engine control unit 9) for performing torque down control for limiting the output torque of the engine 1).
Cruise control unit 14a calculates a target driving force F ^* for realizing the cruise control, the target driving force F ^*, the operating line map by the relationship between the rotational speed and torque of the drive source (engine 1) Use to distribute to target gear ratio and target torque.
A shift request for obtaining the allocated target gear ratio is output to the CVT control means (CVT control unit 8), and a torque down request for obtaining the allocated target torque is output to the travel drive source control means (engine control unit 9). Output (FIG. 3).
As described above, the driving force control is performed by the gear ratio control and the torque down control, thereby utilizing the existing cooperative technology of the gear ratio control and the torque down control of the traveling drive source (engine 1), and at a constant speed. Driving force control can be performed during the running mode.

  The vehicle driving support control apparatus of the present invention has been described based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and design changes and additions are allowed without departing from the spirit of the invention according to each claim of the claims.

In the first embodiment, an example in which the actual vehicle speed VSP at the moment of entering the constant speed region C is set as the target vehicle speed VSP ^* as the constant speed traveling control unit 14a is shown. However, the constant speed traveling control unit may be an example in which the actual vehicle speed after a predetermined time has elapsed after entering the constant speed region is set as the target vehicle speed.

  In the first embodiment, an example in which the driving force control is performed by the gear ratio control and the torque down control as the constant speed traveling control unit 14a is shown. However, as the constant speed traveling control unit, the driving force control may be performed only by the output torque control of the traveling drive source. In addition, the driving force control may be performed by transmission ratio control and brake control.

  In the first embodiment, the example in which the constant speed traveling control unit 14a performs the constant speed traveling control by setting the target vehicle speed of the host vehicle while the constant speed traveling control mode is being executed is shown. However, as the constant speed travel control unit, during the execution of the constant speed travel control mode, the vehicle travels at the target vehicle speed when there is no preceding vehicle, and ensures the distance between the host vehicle and the preceding vehicle when there is a preceding vehicle. Of course, it is also possible to execute a known constant speed running control such as running while running.

  In the first embodiment, the driving support control device according to the present invention is applied to an engine vehicle equipped with a belt-type continuously variable transmission including a torque converter, a forward / reverse switching mechanism, a variator, and a final reduction mechanism. However, the driving support control device of the present invention is not limited to a belt-type continuously variable transmission using only a variator, but is applied to a vehicle equipped with a belt-type continuously variable transmission with a sub-transmission in which the variator and the sub-transmission are connected in series. It may be applied. Further, the applied vehicle is not limited to an engine vehicle, and can be applied to a hybrid vehicle in which an engine and a motor are mounted on a traveling drive source, an electric vehicle in which a motor is mounted on a traveling drive source, and the like.

1 Engine (driving drive source)
CVT belt type continuously variable transmission (continuously variable transmission)
2 Torque converter 3 Forward / reverse switching mechanism 4 Variator 5 Final deceleration mechanism 6 Drive wheel 8 CVT control unit (driving force control means: CVT control means)
9 Engine control unit (driving force control means: driving source control means for traveling)
12 Engine speed sensor 14 Driving support control unit (driving support control means)
14a Constant speed traveling control unit 81 Vehicle speed sensor 87 Accelerator opening sensor 88 Constant speed traveling selection switch

Claims (8)

Driving force control means for controlling the driving force transmitted from the driving source for traveling to the driving wheel;
Driving support control means for performing driving support control to reduce the driving operation burden on the driver,
When the target vehicle speed is set, the driving support control means is provided with a constant speed traveling control unit that executes a constant speed traveling mode in which the vehicle speed is maintained by driving force control that matches the actual vehicle speed with the target vehicle speed,
When the accelerator opening by the driver's accelerator operation enters the constant speed region from the lower threshold value set to the intermediate accelerator opening region to the upper threshold value during traveling, the constant speed traveling control unit enters the constant speed region. An actual vehicle speed when entering the vehicle is set to the target vehicle speed, and the constant speed running mode is started. In the vehicle driving support control device according to claim 1,
The constant speed travel control unit is configured to reduce the entire accelerator opening range to the constant speed region based on an accelerator opening width from the lower threshold to the upper threshold, an acceleration region having a higher opening than the upper threshold, and the lower It is divided into a deceleration area with a lower opening than the side threshold,
The vehicle lower side threshold and the upper side threshold are set to higher accelerator opening values as the vehicle speed increases in accordance with the rising gradient of the load / load driving force due to the increase in vehicle speed. In the vehicle driving support control device according to claim 1 or 2,
The constant speed traveling control unit, after executing the constant speed traveling mode, after the accelerator opening degree enters the acceleration region by a driver's accelerator depressing operation, the accelerator opening amount enters the constant speed region by an accelerator depressing operation. And rewrite the target vehicle speed to the actual vehicle speed when entering the constant speed region,
During execution of the constant speed travel mode, after the accelerator opening is entered into the deceleration area by the driver's accelerator depressing operation, the accelerator opening is entered into the constant speed area when the accelerator is depressed. The target vehicle speed is rewritten to the actual vehicle speed at the time of driving. In the vehicle driving support control device according to claim 3,
The constant speed running control unit, after executing the constant speed running mode, when the accelerator pedal increase operation is performed by the driver, after narrowing the upper threshold, gradually return the upper threshold,
A vehicle driving support control device characterized in that when the driver performs an accelerator depressing operation during execution of the constant speed running mode, the lower threshold value is gradually reduced and then gradually returned to the original value. In the vehicle driving support control device according to claim 3 or 4,
The constant speed traveling control unit performs vehicle speed feedback control using a deviation between the target vehicle speed and the actual vehicle speed when the accelerator opening remains in the constant speed region while executing the constant speed traveling mode, and zero target acceleration. Acceleration feedback control
During execution of the constant speed running mode, when the accelerator opening enters the acceleration region by the driver's accelerator depressing operation, acceleration feedback control is performed with the target acceleration as positive,
A vehicle driving support control apparatus that performs acceleration feedback control with a negative target acceleration when the accelerator opening amount enters the deceleration region by a driver's accelerator depressing operation during execution of the constant speed travel mode. In the vehicle driving support control device according to claim 5,
The constant speed traveling control unit prohibits the vehicle speed feedback control when the actual vehicle speed exceeds the target vehicle speed at that time during acceleration feedback control in the acceleration region, and the actual vehicle speed is equal to or less than the target vehicle speed at that time. And allow the vehicle speed feedback control,
During acceleration feedback control in the deceleration region, the vehicle speed feedback control is prohibited if the actual vehicle speed is less than or equal to the current target vehicle speed, and the vehicle speed feedback control is permitted if the actual vehicle speed exceeds the current target vehicle speed. A vehicle driving support control apparatus characterized by the above. In the vehicle driving support control device according to claim 5 or 6,
The constant speed traveling control unit estimates a load / load driving force necessary to maintain the vehicle speed against the traveling load resistance,
A vehicle that calculates positive and negative target accelerations used in the acceleration feedback control based on a surplus driving force calculated using a maximum driving force and a zero driving force on the basis of the load / load driving force. Driving support control device. In the vehicle driving support control device according to any one of claims 1 to 7,
As the driving force control means, a CVT control means for controlling a gear ratio of a continuously variable transmission mounted in a drive system, and a traveling drive source control means for performing torque down control for limiting an output torque of the traveling drive source. And having
The constant speed traveling control unit calculates a target driving force for realizing constant speed traveling control, and calculates the target driving force with a target gear ratio using an operation line map based on a relationship between the rotational speed and torque of the traveling driving source. Distribute to the target torque,
A vehicle that outputs a shift request for obtaining the target gear ratio allocated to the CVT control means, and outputs a torque down request for obtaining the target torque allocated to the driving source control means for traveling. Driving support control device.