JP5050368B2 - Vehicle driving force control device - Google Patents

Description

  The present invention relates to a vehicle driving force control device, and more particularly, a vehicle that controls the acceleration state and deceleration state of a vehicle based on the positional relationship with a preceding vehicle, and performs control to open a throttle opening when acceleration is necessary. The present invention relates to a driving force control device.

  2. Description of the Related Art There is known a vehicle driving force control device that controls an acceleration state or a deceleration state of a vehicle based on a positional relationship with a preceding vehicle and performs control to increase a driving force when acceleration is necessary. Japanese Patent Laid-Open No. 11-39600 (Patent Document 1) describes a driving force and a driving force so as to maintain a set inter-vehicle distance between the host vehicle and the preceding vehicle based on the inter-vehicle distance between the host vehicle and the preceding vehicle, relative speed, and the like. In the inter-vehicle distance control for controlling the braking force, for example, it is described that when the front vehicle is not detected on the same lane as the own vehicle due to the lane change of the front vehicle or the own vehicle, the vehicle shifts to the constant speed traveling of the target vehicle speed. ing.

JP-A-11-39600 Japanese Patent Laid-Open No. 7-17297 JP-A-8-118997

  In the vehicle driving force control device, when it is detected that the vehicle is no longer in front of the host vehicle, the control is performed to increase the host vehicle to the set vehicle speed. May cause a downshift. The downshift accompanying execution of such driving force control (control to open the throttle opening) is more likely to be performed unexpectedly by the driver than downshifts other than during driving force control (normal time). Therefore, in this case, the driver may feel uncomfortable due to a feeling of delay or a decrease in the driving force or an increase in engine sound due to an increase in the engine speed.

  An object of the present invention is to provide a vehicle driving force control device capable of suppressing a driver's uncomfortable feeling due to a downshift occurring during driving force control.

The vehicle driving force control device of the present invention controls the acceleration state and deceleration state of the vehicle based on the positional relationship with the vehicle ahead, and controls the vehicle to open the throttle opening when acceleration is required. In the control device, a means for obtaining a target acceleration when the acceleration is required, and an acceleration obtained by opening the throttle opening without performing acceleration control to the side that increases the transmission gear ratio of the transmission. When the value obtained by subtracting the acceleration obtained by opening the throttle opening from the target acceleration is within a predetermined value larger than zero and within a predetermined value, compared to when not within the predetermined value And means for reducing the shift width toward the side that increases the gear ratio.

  In the vehicle driving force control device according to the present invention, reducing the shift width toward the side where the speed ratio is increased includes prohibiting shifting toward the side where the speed ratio is increased. Yes.

  In the vehicle driving force control device according to the present invention, when the acceleration is necessary, the distance between the vehicle ahead and the vehicle ahead is lost, the distance between the vehicle ahead and the vehicle ahead is preset. It is characterized in that at least one of the cases where the predetermined distance is exceeded is included.

  According to the vehicle driving force control device of the present invention, it is possible to suppress a driver's uncomfortable feeling due to a downshift occurring during driving force control.

  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.

  In the ACC device with an inter-vehicle distance control function, this embodiment is set when the vehicle ahead disappears during ACC operation, when the vehicle ahead is lost, or when it is determined that acceleration of the host vehicle is necessary. When the vehicle is accelerated to the vehicle speed, it is determined whether or not there is a downshift, and if the difference between the maximum acceleration obtained without the downshift and the target acceleration is equal to or less than a predetermined value, the downshift is avoided. Is. As a result, it is possible to suppress a driver's uncomfortable feeling due to a downshift occurring during driving force control.

  As a configuration of the present embodiment, as will be described in detail below, a means for measuring or calculating the inter-vehicle distance, the relative vehicle speed, and the acceleration of the front vehicle, such as an inter-vehicle distance sensor using a millimeter wave radar, With inter-vehicle distance control that performs shift control of automatic transmissions (AT, CVT, HV (AT mounted on hybrid vehicles), MMT (manual T / M with automatic transmission mode)) based on information such as the above-mentioned inter-vehicle distance ACC (Adaptive cruise control system), means for controlling the electronic throttle, and means for correcting and controlling the downpoint of the automatic transmission during ACC operation are assumed.

  In FIG. 2, reference numeral 10 denotes an automatic transmission, and 40 denotes an engine. 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 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 acceleration sensor 90 detects vehicle deceleration (deceleration acceleration). The inter-vehicle distance measuring unit 100 includes a sensor such as a laser radar sensor or a millimeter wave radar sensor mounted on the front part of the vehicle, and measures the inter-vehicle distance from the preceding vehicle.

  The shift point correction control unit 118 can be provided as a part of the CPU 131. The shift point correction control unit 118 compares the acceleration obtained by opening the throttle opening without performing acceleration control to increase the gear ratio during the operation of the ACC and the target acceleration, Based on the comparison result, the downpoint of the automatic transmission is corrected and controlled to avoid downshifting.

  The control circuit 130 inputs signals indicating detection results of the throttle opening sensor 114, the engine speed sensor 116, the vehicle speed sensor 122, the shift position sensor 123, and the acceleration sensor 90, and changes the switching state of the pattern select switch 117. A signal indicating the measurement result by the inter-vehicle distance measuring unit 100 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 receives signals from the sensors 114, 116, 122, 123, and 90, signals from the switch 117, and signals from the inter-vehicle distance measuring unit 100. Solenoid valve driving units 138a, 138b, and 138c are connected to the output port 135.

  The ROM 133 stores a program in which the operations (control steps) shown in the flowchart of FIG. 1 are described in advance, and a shift map for shifting the gear 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.

  Next, the operation of the first embodiment will be described with reference to FIG. FIG. 1 shows a control flow at the end of ACC. 1 is mainly executed by the control circuit 130.

[Step S10]
In step S10, it is determined whether or not an ACC operation switch (not shown) is on. The operation switch is operated by the driver. As a result of the determination in step S10, if the ACC operation switch is on, the process proceeds to step S20. Otherwise, in step S120, after the flag F is set to 0 (if F = 0 from the front, it remains as it is. The control flow is reset.

[Step S20]
In step S20, it is determined whether the inter-vehicle distance control is being executed. For example, when there is no vehicle ahead of the host vehicle due to the lane change of the host vehicle or the host vehicle, or the host vehicle detecting means (the inter-vehicle distance measuring unit 100) such as a laser radar device of the host vehicle is Is lost, the execution condition of the inter-vehicle distance control is not satisfied (the end condition of the inter-vehicle distance control is satisfied), so it is determined that the inter-vehicle distance control is not being executed. If the result of determination in step S20 is affirmative, the process proceeds to step S100. Otherwise, the process proceeds to step S30.

[Step S100]
In step S100, it is determined whether the vehicle needs to be accelerated. For example, when the distance between the preceding vehicle and the own vehicle is more than a predetermined value, it is determined that the inter-vehicle distance control is being executed (step S20-Y), but it is determined that the own vehicle needs to be accelerated. The The determination of the necessity of acceleration of the own vehicle can be made based on at least one of the distance between the preceding vehicle and the own vehicle and the driver's accelerator-on operation. As a result of the determination in step S100, if the determination is affirmative, the process proceeds to step S30. If not, after the flag F is set to 1 in step S110 (if F = 1 from the front, it remains as it is). The control flow is reset.

[Step S30]
In step S30, the flag F is checked. As a result, when the flag F is 0, the inter-vehicle distance control is not started, and thus this control flow is reset.

[Step S40]
In step S40, the shift point correction control unit 118 determines whether or not a downshift occurs. When this step S40 is performed (when the flag F is determined to be 1 in step S30), the inter-vehicle distance control has been started so far (the flag F is 1), and the inter-vehicle distance control is not being executed. (Step S20-N), or when it is determined that acceleration of the vehicle is necessary (step S100-Y).

  In this case, in step S40, in order to increase the vehicle to a preset vehicle speed, it is determined whether or not a downshift occurs by opening the electronic throttle. That is, based on the target acceleration, running resistance, engine torque characteristics, etc., the throttle opening required to accelerate the vehicle to a preset vehicle speed is obtained, and the throttle opening is compared with the down line of the shift diagram. Then, it is determined whether or not a downshift occurs. As a result of the determination, if it is determined that a downshift occurs, the process proceeds to step S50, and if not, the process proceeds to step S70.

  In FIG. 3, it is assumed that the throttle opening and vehicle speed before step S40 are point A. As shown in the figure, when the point is A, the shift speed is 6th. In step S40, a throttle opening required for increasing the vehicle speed to a preset vehicle speed is obtained as a C point, and the C point crosses the down line 501 from the 6th speed to the 5th speed, so that a downshift occurs. Then, it is determined (a downshift occurs at point B on the down line 501).

[Step S50]
In step S50, the shift point correction control unit 118 calculates the difference between the acceleration (maximum acceleration) when the downshift is not caused and the target acceleration, and the difference is equal to or less than a predetermined value (difference). ≦ predetermined value) is examined.

  FIG. 4 shows the relationship between the accelerator opening and the throttle opening. The accelerator opening corresponding to the throttle opening at points A, B, and D shown in FIG. 3 is the points A ', B', and D ', respectively. FIG. 5 shows the relationship between the accelerator opening and the driving force F when the shift speed is 6th. As shown in FIG. 3, at a certain vehicle speed, a downshift from 6th speed to 5th speed occurs when the throttle opening is at point B (accelerator opening is at point B '). As shown in FIG. 5, the down point B (B ′) is normally a point B (B ′) where the driving force F is saturated to some extent (the driving force F increases only by ΔF even if the accelerator opening is further increased). Is not set).

  In step S50, in order to avoid a downshift (step S60), the above-mentioned downshift is not performed (acceleration control to increase the gear ratio of the automatic transmission is not performed) (in this example, the current stage) The acceleration when the accelerator opening is fully open D ′ is compared with the target acceleration. Whether or not the target acceleration can be achieved when not downshifting can be easily determined by determining based on the acceleration when the accelerator opening is fully open D '. As a result of the determination in step S50, when it is determined that the difference between the acceleration when the downshift is not generated and the target acceleration is equal to or less than a predetermined value set in advance, that is, the above-described even without downshifting. If it is determined that the target acceleration can be substantially achieved, the process proceeds to step S60. Otherwise, the process proceeds to step S70.

[Step S60]
In step S60, the shift point correction control unit 118 avoids downshifting. Specifically, the down line in the shift diagram is operated to prevent a down shift even when the electronic throttle is fully opened. For example, in the example of FIG. 3, the down line 501 is changed to a down line 502. Thereby, even if the throttle opening is fully opened D from the point A, it is possible to prevent a downshift from occurring. As a result, while making it possible to substantially generate the target acceleration, it is possible to suppress the driver's uncomfortable feeling due to the downshift occurring during driving force control. After step S60, the process proceeds to step S70.

[Step S70] to [Step S90]
In step S70, return control is performed. This return control is a control for setting a predetermined acceleration set in advance according to the time from the start of the control end routine and opening the throttle opening so as to realize the acceleration. After step S70, in step S80, the control circuit 130 checks whether the ACC termination condition is satisfied. If the condition is satisfied, the flag F is set to 0 in step S90 and The control flow is reset. On the other hand, when a negative determination is made in step S80, this control flow is reset.

  According to the present embodiment, when the ACC is in operation (step S10-Y) and it is determined that the inter-vehicle distance control is not being executed (step S20-N, for example, the vehicle ahead or the own vehicle changes lanes). As a result, when there is no vehicle ahead of the host vehicle, or when the inter-vehicle distance measuring unit 100 has lost the preceding vehicle, or when it is determined that acceleration of the vehicle is necessary (step S100-Y, for example, When the distance between the vehicle ahead and the vehicle is more than a predetermined value), it is determined whether or not a downshift occurs by opening the throttle to increase the vehicle to a preset vehicle speed. If it is determined that a downshift will occur (S40-Y), and the throttle is opened when the downshift is not performed, the target acceleration and If the acceleration closer it is obtained (step S50-Y), it is not carried out a downshift (step S60). As a result, it is possible to suppress a driver's uncomfortable feeling due to a downshift occurring during driving force control.

  The difference between the target acceleration and the acceleration obtained by opening the throttle can be reduced by supplementing with the power of a drive source such as an electric motor provided separately from the engine, and the driver's uncomfortable feeling can be further suppressed. is there.

  In the above-described embodiment, a single shift (shift from 6th speed to 5th speed) has been described, but the present invention can also be applied to multiple shifts. In this case, for example, the shift from the 6th speed to the 5th speed is permitted, and this embodiment can be applied to the shift from the 5th speed to the 4th speed.

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 for demonstrating the shift map of 1st Embodiment of the driving force control apparatus for vehicles of this invention. It is a figure which shows the relationship between the accelerator opening of 1st Embodiment of the driving force control apparatus for vehicles of this invention, and throttle opening. It is a figure which shows the relationship between the accelerator opening of 1st Embodiment of the driving force control apparatus for vehicles of this invention, and driving force.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Automatic transmission 40 Engine 90 Acceleration sensor 100 Inter-vehicle distance measurement part 114 Throttle opening sensor 116 Engine speed sensor 118 Shift point correction control part 122 Vehicle speed sensor 123 Shift position sensor 130 Control circuit 131 CPU
133 ROM
501 Down line before change 502 Down line after change

Claims (3)

In the vehicle driving force control device that controls the acceleration state and deceleration state of the vehicle based on the positional relationship with the vehicle ahead, and performs control to open the throttle opening when acceleration is required,
Means for determining a target acceleration when the acceleration is required;
Means for obtaining acceleration obtained by opening the throttle opening without performing acceleration control to the side that increases the transmission gear ratio of the transmission;
When the value obtained by subtracting the acceleration obtained by opening the throttle opening from the target acceleration is within a predetermined value that is larger than zero and within a predetermined value, the speed change is smaller than when the value is not within the predetermined value. A vehicle driving force control device comprising: means for reducing a shift width toward the side that increases the ratio. The vehicle driving force control device according to claim 1,
Decreasing the shift width toward the side that increases the gear ratio includes prohibiting a shift toward the side that increases the gear ratio. The vehicle driving force control device according to claim 1,
When there is a need for acceleration, at least when the vehicle ahead is lost, when the vehicle ahead is lost, and when the distance between the vehicle ahead is equal to or greater than a predetermined distance set in advance Any one of them is included. A vehicle driving force control device.

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