JPH0419337A - Automotive driving force control device and control method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a driving force control device and control method for an automobile.

[Conventional technology]

Generally, the driving force of an automobile can be controlled by a combination of an engine and a transmission.

However, in the conventional device, the engine and transmission were each controlled separately, which caused a major problem in drivability.

Therefore, as disclosed in Japanese Patent Application Laid-Open No. 64-4544, attempts have been made to improve drivability by increasing or decreasing engine output during upshifting or downshifting of the transmission.

[Problem to be solved by the invention]

However, even with such a proposal, there is still a problem in that in actual cars, there is still insufficient agreement between the drivability required by the driver and the actual drivability of the car. there were.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automobile driving force control device and control method that can provide a sufficient sense of coincidence between the drivability required by the driver and the actual drivability of the automobile.

[Means to solve the problem]

The characteristics of the present invention are as follows.

(a) Engine torque control means for controlling the engine torque output from the engine of the automobile; (b) Drive torque control means for controlling the driving torque that drives the automobile from the combination of the engine torque and the shift position of the transmission. (c) Torque control that causes the engine torque control means and/or drive torque control means to function in order to perform torque control using engine torque, drive torque, or a combination of engine torque and drive torque in response to the torque requested by the driver. There is a driving force control device for an automobile comprising means.

[Effect]

According to such a configuration, the engine torque and/or the driving torque are determined in accordance with the torque characteristics requested by the driver, so that the sense of torque consistency is enhanced.

〔Example〕

Examples of the present invention will be described in detail below.

FIG. 1 shows a power train system of an automobile, and its components 9 and their functions will be explained based on reference numbers.

The driving torque control means 2 controls the amount of depression of the accelerator pedal 1.
Alternatively/and input to the engine torque control means 3.

In the engine torque control means 3, a throttle controller 6 (
The engine torque control means 3 drives and controls the motor, throttle valve, throttle sensor), fuel injection device 7A, and ignition device 7B. The drive torque control means 2 also controls the automatic transmission 30. The shift solenoid 8, lock-up solenoid 9, etc. are driven by proportional or duty control to engage and disengage the speed change clutch 10 and clock-up clutch 11.

This speed change control is combined with engine torque control to perform drive torque control.

Shift position and engine torque control, particularly drive torque control based on a combination of throttle opening, is determined from the vehicle speed obtained from a signal from a rotation sensor 12 provided on the drive shaft and the amount of depression of the accelerator pedal 1. Further, in this embodiment, the engine torque control means 3 and the drive torque control means 2 are connected to the low power network 1 to the work (LAN).
are electrically connected and communicated. Furthermore, when a high-performance computer such as a 32-bit computer is used, it is possible to perform cooperative control of the engine and the transmission with one control means, as shown in the control means 13 surrounded by a solid line.

FIG. 2 is a schematic diagram for basically explaining the control method of the present invention. The horizontal axis represents the vehicle speed, while the vertical axis represents the accelerator depression amount, that is, the driving torque. In Fig. 2, the solid line shows the driving torque when the throttle is fully open;
The section [a-b] is the 2nd speed region, the section [b-c] is the 3rd speed region, and the period after [C→C] is the 4th speed region. Next, the target torque for the accelerator pedal depression amount is as shown on the vertical axis: vehicle speed [0-a] section is drive torque, vehicle speed [a-b1 section is drive torque, vehicle speed [b-c] section is engine torque. , and after vehicle speed C, engine torque is used. For example, vehicle speed [
In the 0-a1 section, if the driver depresses the accelerator pedal to a value B, the target drive torque B corresponds to the access depressing amount, so the shift position is set to 3rd speed and the throttle opening is fully opened. Further, when the vehicle speed is after b, the drive torque of CD cannot be obtained even if the accelerator pedal is depressed to the maximum, so the target torque of the accelerator pedal depression amount needs to be the engine torque. Vehicle speed [
0-b] section, it is necessary to perform control using a combination of drive torque and engine torque.

3 to 5 are flowcharts for executing the control shown in FIG. 2. In step (hereinafter referred to as S) 1, the accelerator pedal depression amount α, which is the driver's requested torque, is led, and in S2, the engine rotation speed Ne is led, and further,
Lead the vehicle speed V in S3. Next, in step 84, it is determined whether the vehicle speed V is below a, and if it is below a, that is, [○-a
] If it is the section, then the accelerator pedal depression amount α is 85.
Determine whether or not is less than or equal to A. If it is less than or equal to A, a command signal to change the gear shift position to 4th speed is output in S6. The target value of the drive torque for the accelerator pedal depression amount α at this time is determined by searching the drive torque-accelerator depression amount map shown in FIG. Then, in S7, engine torque control is determined from the accelerator pedal depression amount α using a function f that takes into account the reduction ratio, etc., and in S8, the throttle opening θ map shown in FIG. Find the opening degree θth, and finally 8
At step 9, the throttle opening degree is output, the throttle controller 6 is driven, and the driving torque requested by the driver is output.

Next, if the accelerator pedal depression amount α is less than or equal to A in S5, it is determined in S1o whether the accelerator pedal depression amount α is less than or equal to B, and if it is less than or equal to B, a 3rd speed command is output in Sll, and in S12 Similarly, the engine torque Te is determined and the process proceeds to S8.

Similarly, if the accelerator depression amount α is 8 or more in S10, it is determined in S13 whether the value is less than or equal to C, and if it is less than C, a 2nd speed command is output in S14. The torque Te is determined and the process proceeds to S8.

Furthermore, if the accelerator depression amount α is equal to or greater than C in S13, S
At step 16, a first speed command is output, and at step S17, the engine torque Te is determined in the same manner as in step S7, and the process proceeds to step S8.

The case where the accelerator depression amount α changes while the vehicle speed is in the interval [0-a] has been described above.

On the other hand, if the vehicle speed is 8 or more in S4, the process proceeds to (2) shown in FIG. 4, and in S18 it is determined whether the vehicle speed is b or more.

8 when it is determined that the vehicle speed is in the [a-b] section in S4 and S18.
19. In S22, it is determined whether the accelerator depression amount α exceeds the value A or B.

After this, steps S20 to S26 and S6 to S17 and S8 in FIG. Processing similar to S9 is executed.

In this case, 1st speed is not selected in the vehicle speed [a-b] section.

Next, when it is determined in S18 of FIG. 4 that the vehicle speed is equal to or higher than b, the process proceeds to step 2 shown in FIG. 5, and it is determined in S27 whether the vehicle speed is equal to or higher than C.

If the vehicle speed is in the [b-c1 section, it is determined in S28 whether the accelerator depression amount is equal to or greater than A, and then in S29 to S32 and S8. At S9, the same process as shown in FIG. 3 is executed.

In this case, 1st speed and 2nd speed are not selected in the vehicle speed [b-c] section.

Finally, if it is determined at 827 that the vehicle speed is equal to or higher than C, the process directly advances to S29, where a 4th speed command is issued and the throttle opening degree is determined.

FIG. 8 is a constant fuel consumption rate diagram. While the horizontal axis represents the engine speed, the vertical axis represents the engine torque, and the broken line represents the engine torque when the throttle is fully open. In FIG. 8, the shaded area is the area with the best fuel efficiency. Further, the solid line indicates the best fuel efficiency movement line until reaching the shaded area.

In other words, it is necessary to increase the engine torque while keeping the engine rotation speed at 1100 Orp, and bring the engine torque to near the maximum while increasing the engine rotation speed by about 2/3 of the engine torque. If the driving torque is controlled as in the present embodiment, the operating range passing on such a line of best fuel efficiency increases, so fuel economy improves.

FIG. 9 is a characteristic diagram of maximum drive torque with respect to vehicle speed of a continuously variable transmission (cVT). As can be seen from the figure, when a continuously variable transmission is used, the gear ratio can be changed freely, so there is no step difference in the driving torque.

Further, the maximum value of the driving torque, which changes depending on the vehicle speed, is made the maximum value of the accelerator opening. In other words, this becomes the target drive torque (accelerator opening degree) for the vehicle speed.

For example, the drive torque D at vehicle speed a becomes the maximum value of the accelerator opening, that is, the maximum target drive torque requested by the driver. At that time, when the accelerator opening is set to C,
The gear ratio changes from Hl to H2, and the engine throttle remains fully open.

Driving torque can be changed.

Also, if the accelerator opening is A at the vehicle speed, change the gear ratio to H.
4, and the throttle opening is fully open.

FIG. 10 shows a control flowchart when a CVT is used. First, S33. In S34, the vehicle speed (vsp) and the accelerator opening (α) are read, and in S35, a map of the accelerator opening (target driving torque) relative to the vehicle speed is searched as shown in FIG. Then, in S36, it is determined whether the accelerator opening degree α is larger than the driving torque of the limit transmission ratio H4 on the high gear ratio side, that is, the target driving torque A. If it is larger, the throttle opening degree θ is fully opened in S37, and in S38 Select the gear ratio that matches the vehicle speed and accelerator opening.

On the other hand, if α is A, the engine torque Te=f in S39
The throttle opening degree θ is determined from (α), and the gear ratio is set to the limit H4 in S40.

In this way, this embodiment provides a sense of consistency between the drivability requested by the driver and the actual drivability of the vehicle.

Next, the present invention will be explained in detail.

FIG. 11 shows the control method of an applied example. The relationship between throttle opening and drive torque differs depending on the gear position, as shown by the broken line. In conventional control, when the accelerator pedal is depressed to gradually increase the driving torque as shown in FIG. 11(a), the gears of the transmission are downshifted one after another as shown by the solid line. On the other hand, the method of the applied example is shown in Fig. 11(b).
When the drive torque is increased, the gear is maintained until the throttle is fully opened, and when even greater drive torque is required, the gear is shifted down. At this time, the throttle is closed at one end to prevent sudden changes in the drive torque, and when the drive torque is further increased, the throttle is fully opened again, and the operation of downshifting is repeated. As explained in FIG. 8, this system makes frequent use of the fully open throttle range and uses a wide range of high gears, which allows the engine speed to be kept low, resulting in good fuel efficiency. Furthermore, since the throttle opening degree is controlled so that the drive torque does not suddenly change during gear shifting, shocks during gear shifting can be reduced.

FIG. 12 shows a control flowchart of the method shown in FIG. 11(b). First, when a timer interrupt signal is input, the accelerator depression angle and vehicle speed are measured in S50. Next 85
1, the driving torque and gear position are calculated from the accelerator depression angle and vehicle speed based on FIG. FIG. 13 shows the relationship between vehicle speed, drive torque, and gear position. The solid line indicates the maximum drive torque relative to vehicle speed. The drive torque is calculated from the maximum drive torque corresponding to the vehicle speed and the accelerator depression angle, and the gear position is determined. Here, since this method frequently uses the vicinity of the throttle fully open, when the throttle is fully open, the gears change unstablely many times due to noise in the accelerator depression angle voltage, etc., resulting in chatter. This is to be prevented. There is a need.

Therefore, when upshifting, the gear position is determined based on the broken line in S52 and S53. By providing such hysteresis, it is possible to prevent chattering during gear change and prevent wear and tear on the transmission.

Next, at 554, engine torque is calculated from the product of drive torque and gear ratio. Next, create in advance in S55,
S56 Calculate throttle opening using a map of throttle opening with respect to engine speed and engine torque
Throttle opening signal.

Outputs a gear shift signal to control engine output and gear shift.

FIG. 14 shows another control method that performs the same speed change and throttle operation as the method shown in FIG. 11(b).

This method performs gear change and throttle control based on the accelerator pedal angle and throttle opening without considering vehicle speed.

FIG. 15 shows the control flowchart.

Measure the accelerator pedal angle and engine speed with S50, and
At 57, the engine speed is the limit engine speed Maxrp.
If the speed exceeds m, shift up at S59 to prevent engine wear and tear. If the engine speed is below Max rpm, 558. At S60, the gear position and throttle opening are determined based on FIG. Next, at 861, a shift signal and a throttle opening signal are outputted to control the shift and engine output. This method is simpler than the method shown in Figure 12,
It has the advantage of short calculation time.

Next, FIG. 16 shows a processing flowchart when the engine rotational speed becomes excessive due to an abnormal operation of the throttle or transmission using the control method shown in FIG. 12. By the timer interrupt, the gear position and engine speed are first measured in S62. When the engine speed becomes equal to or higher than the limit engine speed in S63, S64. In S65, shift up control is performed to reduce the engine speed to prevent engine wear and tear.

In addition, it is also possible to notify the driver of an abnormality using a warning light.

Next, the present invention will be explained in further detail.

FIG. 17 shows a control block diagram during deceleration.

Accelerator opening detection means 31 and brake depression force detection means 32
Then, the deceleration determining means 33 determines whether the driver wants to decelerate. Thereafter, the deceleration determining means 34 determines the deceleration intended by the driver.

At this time, if the deceleration requested by the driver is the minimum, the shift position with the best fuel efficiency, such as N (neutral), is directly output to the shift controller 35. In addition, if the deceleration requested by the driver exceeds a certain value, the gear ratio calculation single stage 36
outputs a gear ratio that matches the required deceleration. Furthermore, the throttle opening calculation means 3 is designed to prevent shock during gear shifting.
7, the throttle opening is determined and output to the throttle controller 38.

FIG. 18 shows a control flowchart of FIG. 17. Initially, in S70, accelerator opening α, brake pedal force β, and vehicle speed V
, read the engine speed Ne.

In S71, it is determined whether the vehicle speed V is equal to or higher than Vo, and if V≧Vo
At this time, it is determined in S72 whether the accelerator opening degree α is O. If the accelerator opening degree α=0, S73. S75
Set a flag (Flg) in S74 and set the arbitrary time x ra
sec, the current gear ratio 1no- is output in S76. Next, when x a+sec has elapsed in S74, the flag (FIG) is cleared in S77, and the value of the brake pedal force β is searched in S7o. If the brake pedal force β is smaller than β0 in S78, the driver determines that inertia deceleration is required, and the driver performs S79.
Set the gear shift position to neutral (i, =N). Next, when the brake pedal force β is smaller than β1 in S80, S8
1, the gear ratio it is a function of the vehicle speed ■ and the engine speed N8 (
Determine from f). After that, in S82, the throttle opening θt
h is determined from the function (g) of the vehicle speed V and the gear ratio 11, and the gear ratio 11 is outputted at the throttle opening θth and S83. Thereafter, as in the above control, the gear ratio and throttle opening are determined based on changes in the brake pedal force. If the brake pedal force β is the maximum β in S84, it is determined that the driver is requesting the maximum braking force, and the process proceeds to S85. S86. From S87, the gear ratio and throttle opening are determined so that the engine speed is high. Moreover, the value from -β0 to β is proportional to the highest controllable gear ratio of the automatic transmission.

FIG. 19 is an overview of the overload reduction system.

For example, in the case of a stepped automatic transmission, since a torque converter is used, an overload region exists as shown by the shaded area in the first speed state in a low vehicle speed range. Therefore, as shown by the broken line, it is necessary to lower the maximum target value of the drive torque (full throttle opening). This prevents impact torque when starting the vehicle. Furthermore, when this method is used, it is possible to use the 2nd, 3rd, and 4th gear shift positions frequently with the smaller target drive torque (accelerator opening), thereby reducing fatigue on the drive system.

FIG. 20 shows a control block diagram for overload reduction. The accelerator opening degree is detected by the accelerator opening degree detection means 31, and the overload determination means 40 determines whether overload control is necessary. If the above control is necessary, the throttle opening degree is determined by the throttle opening degree calculating means 37, and then the corrected throttle opening degree is determined by the driving torque correcting means 42 and outputted to the throttle controller. The torque ratio of the torque converter is determined by the torque ratio calculation means 41 and inputted to the drive torque correction means for correction.

FIG. 21 is a control flowchart of FIG. 20. S
At 90, read the accelerator opening α and engine speed Ne. Then, when the accelerator opening degree α is α1 or more at 89.1, that is, when the vehicle speed is in a low vehicle speed range below the vehicle speed Vo (30 km/h, etc.) and the gear shift position is 1st gear, the gear ratio is 11 at S92.
is output, and in S93 the target drive torque pressure is set to the accelerator opening α.
It is determined by the function f. After that, in S94, the throttle opening θ
is determined by g(Tt+11.Ne) and output in S95. At this time, the maximum value of the driving torque is set to be the maximum value of the accelerator opening.

FIG. 22 shows a drive torque correction system based on atmospheric pressure changes. Since atmospheric pressure changes between highlands (broken line) and lowlands (solid line), there is a difference in maximum drive torque. Therefore, in the case of highlands, by using the gear ratio B' when the vehicle speed is a, it is possible to obtain the same driving torque as on flatlands, and it is possible to satisfy the driving torque required by the driver due to changes in atmospheric pressure. It is.

FIG. 23 is a block diagram of atmospheric pressure correction control.

Atmospheric pressure detection means 43 detects atmospheric pressure, and vehicle speed detection means 44. A corrected drive torque is determined by a corrected drive torque calculation means 45 in accordance with the vehicle speed and engine rotation speed detected by the engine rotation speed detection means 46. Thereafter, the corrected speed ratio calculating means 47 calculates the corrected speed change ratio, and the corrected engine output calculating means 48 calculates the corrected throttle opening and outputs them to the speed change controller 35 and the throttle controller 38, respectively.

FIG. 24 shows a control flowchart of FIG. 23. S
Atmospheric pressure P at IO○, vehicle speed V at 5LOL.

At 5102, the engine speed Ne is read. And 5
In step 103, the corrected drive torque ΔTo is determined from j'(p+V), and then in step 5104, the corrected gear ratio Δ1 is determined by g(Δ”ro,
Ne). Then, at S], 05, h(Δ1.
It is determined whether θ) and ΔTo match. If they match, there is no need to correct the throttle opening, so the gear ratio Δ is directly output in step 5108. If they do not match in 5105, the corrected throttle opening Δθ is determined in 8106.
is obtained from J(Δ+, Ne), output at 5107, and the gear ratio Δ1 at that time is output at 5108.

FIG. 25 is a schematic diagram of air-fuel ratio control. To improve fuel efficiency, the air-fuel ratio (A/F) is made smaller and richer only in the shaded power zone. In other areas, the air-fuel ratio (A/F
) needs to be made larger and leaner.

FIG. 26 shows an air-fuel control flowchart.

S1101? At gear ratio i, 5III, vehicle speed V, 511
2 reads the throttle opening degree θ. 5113 and gear ratio i
is 1st gear 11 or not, and at 5114, the vehicle speed V is Vo.
(Example: 60km/h), and in 5115, it is determined whether the throttle opening θ is greater than or equal to θ-, and i=i
If V≦Vo and θ≧θ, the rich map (A/F=12) is searched at 8116, and the fuel amount Tp is output at 5117.

In cases other than the above conditions, use 5118 to map the lean map (A/
F=19) and outputs Tp in 5117.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain a sufficient sense of correspondence between the drivability required by the driver and the actual drivability of the automobile that follows the same.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a vehicle control device according to an embodiment of the present invention, FIG. 2 is a diagram showing an outline of control of a vehicle control device according to an embodiment of the present invention, and FIGS. 3 to 5 are Figure 2 is a flowchart for executing the control, Figure 6 is a diagram showing the correspondence between accelerator and torque, Figure 7 is a throttle opening map that corresponds to rotation speed and torque, and Figure 8 is a map that corresponds to rotation speed and torque. Fig. 9 is a diagram showing an outline of another control using a continuously variable transmission, Fig. 10 is a control flowchart of Fig. 9, and Fig. 11 is for explaining another application example of the present invention. FIG. 12 is a flowchart for implementing the characteristics shown in FIG. 11, FIG. 13 is a characteristic diagram of vehicle speed-drive torque-shift position, and FIG. 14 explains another application example of FIG. 11. 15 is a flowchart for implementing the characteristics shown in FIG. 14, FIG. 16 is a flowchart for abnormality countermeasures following the flowchart shown in FIG. 12, and FIG. 17 is a flowchart for implementing the characteristics shown in FIG. FIG. 18 is a flowchart of the example, FIG. 19 is a characteristic diagram of another application example of the present invention, FIG. 20 is a configuration diagram for implementing the characteristics of FIG. 19, and FIG.
Fig. 1 is a flowchart thereof, Fig. 22 is a characteristic diagram of another application example of the present invention, Fig. 23 is a block diagram for implementing the characteristics of Fig. 22, Fig. 24 is a flowchart thereof, and Fig. 25 is a characteristic diagram of another application example of the present invention. A characteristic diagram of another application example of the invention, FIG. 26, is a flowchart for implementing the characteristic of FIG. 25. DESCRIPTION OF SYMBOLS 1... Accelerator pedal, 2... Drive torque control means, 3... Engine torque control means, 4... Engine, 6... Throttle controller, 7A... Fuel injection device, 7B...・Ignition device, 8...Shift solenoid, 1
0...speed change clutch, 30...automatic transmission.

Claims (1)

[Claims] 1. (a) Engine torque control means for controlling engine torque output from an engine of an automobile; (b) Drive for driving an automobile from a combination of the engine torque and a shift position of a transmission. Drive torque control means for controlling torque; (c) the engine torque control means and/or drive to perform torque control using engine torque, drive torque, or a combination of engine torque and drive torque with respect to the torque requested by the driver; A driving force control device for an automobile comprising a torque control means for making the torque control means function. 2. In a vehicle that controls the engine torque and the gear shift position, the vehicle's driving force outputs the torque requested by the driver by the combination of engine torque and the drive torque determined by the engine torque and the gear shift position. Control method. 3. (a) Vehicle speed detection means for detecting the vehicle speed of the automobile; (
b) Accelerator detection means for detecting the degree of accelerator depression of the automobile; (c) Gear shift position control means for determining the gear shift position from the vehicle speed and the amount of accelerator depression; (d) Engine torque determination that determines engine torque from the amount of accelerator depression. Means; (e) A driving force control device for an automobile comprising a throttle opening degree control means that determines a throttle opening degree from engine torque and rotational speed. 4. In an engine equipped with at least a throttle controller for controlling a throttle valve disposed in an intake passage of the engine and a transmission mechanism disposed between the engine and the drive wheels, when the throttle valve reaches near full open, the transmission mechanism A driving force control method for an automobile, wherein the throttle valve is closed to a predetermined opening degree in synchronization with the speed change or after the speed change. 5. In an engine equipped with at least a throttle controller that controls a throttle valve arranged in the intake passage of the engine and a transmission mechanism arranged between the engine and the drive shaft, when the throttle valve is fully opened, the transmission mechanism is shifted down. A driving force control method for an automobile in which the throttle valve is closed to a predetermined opening degree in synchronization with or behind the downshift, and then the throttle valve is opened. 6. In an engine equipped with at least a throttle controller for controlling a throttle valve disposed in an intake passage of the engine and a transmission mechanism disposed between the engine and a drive shaft, when the throttle valve reaches near full open, the transmission engine , the throttle valve is closed to a predetermined opening degree in synchronization with or after the shift, and when the brake is depressed, the shift position and throttle opening are set according to the amount of depression of the brake. Force control method.