JP2000054876A - Device for controlling driving force of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transiently control an engine torque so that shock by torque step difference may not be generated when shifting from an automatic transmission mode to a manual transmission mode. SOLUTION: In an automatic transmission mode, an engine output is controlled so as to set up a target engine torque TeA for the automatic transmission mode found out by dividing a required driving shaft torque which can be found out from an accelerator pedal stepping amount and a vehicle speed by a transmission ratio of a driving system. On the other hand in a manual transmission mode, the engine output is controlled so as to set up a required engine torque TeD found out from the accelerator pedal stepping amount and an engine speed, thereby disorder feeling can be removed that a relation between accelerator pedal operation and the engine torque is different per shift stage in manual transmission. Torque difference is generated when shifting from the automatic transmission to the manual gear change, however, just after a shifting period t1, a target engine torque TeMS for shifting to the manual transmission mode is processed by a filter so as to be changed while being matched with the transmission response delay of a continuously variable transmission, and at the time of shift finishing period t2, TeMS reaches TeD.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force control apparatus for a vehicle equipped with a continuously variable transmission, and more particularly, to a method for controlling a change in engine torque when the continuously variable transmission is switched from an automatic transmission mode to a manual transmission mode. The present invention relates to a technique for appropriately controlling in relation to a shift response delay of a continuously variable transmission.

[0002]

2. Description of the Related Art A continuously variable transmission represented by a V-belt type continuously variable transmission or a toroidal type continuously variable transmission generally determines a target gear ratio from an engine required load and a vehicle speed. Shift control is performed to achieve the target gear ratio. Therefore, during acceleration in which the driver depresses the accelerator pedal to increase the required engine load, the target gear ratio is changed to be larger (to be a lower speed gear ratio), and the continuously variable transmission is set to the increased target gear ratio. When the vehicle is downshifted to the gear ratio, and conversely, during a low-load operation in which the driver returns the accelerator pedal to reduce the required engine load, the target gear ratio is changed to be smaller (to be a higher gear ratio). The continuously variable transmission is upshifted to the reduced target gear ratio.

On the other hand, as a technique for obtaining a required driving force of a vehicle, there is a technique described in, for example, JP-A-7-172217. This technology calculates the basic required driving force of the vehicle from the vehicle speed and the amount of depression of the accelerator pedal, and adds the estimated running resistance that can be estimated from the vehicle speed to the original required driving force required to drive the wheels. It is assumed that.

[0004] By the way, in the above-mentioned conventional shift control of a continuously variable transmission, the required driving force obtained by the technique disclosed in the above-mentioned literature cannot be accurately realized. In any case, it is impossible at all to achieve the required driving force obtained in such a manner as to minimize the fuel consumption of the engine.

In order to realize the required driving force in such a manner that the fuel efficiency of the engine is minimized, the required driving force is controlled by controlling the output of the engine and the shift control of the continuously variable transmission (engine speed control). Driving force control realized by an appropriate combination with
A driving force control technique as described in Japanese Patent No. 9536 has been proposed. This technology presumes a power train that is a combination of an engine whose output can be changed by factors other than the accelerator pedal operation amount and a continuously variable transmission, and calculates the target drive shaft torque from the accelerator pedal operation amount and vehicle speed. A target gear ratio is calculated based on the target drive shaft torque to contribute to the speed change control of the continuously variable transmission. At the same time, a target engine torque is calculated from the target drive shaft torque and the current gear ratio, and the engine torque is adjusted to the target torque. That is, the output of the engine is controlled to a value.

On the other hand, automatic transmissions including continuously variable transmissions are easy to drive because there is no need for the driver to perform shifting operations, but lack the fun of driving.
As described in Japanese Patent Publication No. 545, an automatic transmission that enables a manual shift has been proposed. This type of automatic transmission allows a driver to manually select an automatic transmission mode or a manual transmission mode.
When the mode is switched from the automatic speed change mode capable of normal automatic speed change to the manual speed change mode, it is possible to shift to any predetermined gear position by a driver's shift operation.

[0007]

A vehicle equipped with a power train, which is a combination of a continuously variable transmission having a manual transmission mode and an engine, is disclosed in Japanese Patent Application Laid-Open No. Sho 62-199536. When the driving force control technique described in the above paragraph is adopted, the characteristic of the relationship between the accelerator pedal operation amount and the engine output during traveling in the manual shift mode differs for each selected shift speed, giving rise to a problem that there is a sense of incongruity.

In the automatic transmission mode, the present invention uses the target engine torque for the automatic transmission mode obtained by dividing the required drive shaft torque by the drive system transmission ratio for the engine output control so as not to cause such a problem. The purpose of this is to use the required engine torque separately obtained from the accelerator pedal operation amount as the target engine torque for engine output control. In addition, the target engine torque is separately set for the automatic transmission mode and the manual transmission mode. In order to solve the problem, it is intended to solve the problem related to the shock caused by the torque step, in view of the fact that a step is generated in the target engine torque when the shift mode is switched, and a shock is likely to occur.

[0009] As shown in FIG. 9, regarding the case of switching from the automatic shift mode to the manual shift mode instantly t _1, to explain the shock caused by the level difference of the target engine torque during shifting mode switching, the target engine torque the shift mode switching time t _1, a sudden change from the target engine torque for the automatic shifting mode to the required engine torque corresponding value described above. By the way, the continuously variable transmission has a shift response delay as shown by the time series change of the actual gear ratio, and the change of the target engine torque is too steep with respect to the shift response delay characteristic, so that the gear ratio is changed to the manual shift mode. The target engine torque is switched from the target engine torque for the automatic transmission mode to a value corresponding to the required engine torque before the gear ratio converges to the gear ratio set in the above. As a result, the drive shaft torque overshoots as indicated by the time-series change, and this causes a shock and a sense of discomfort.

On the other hand, if the change in the target engine torque is too slow with respect to the shift response delay characteristic, the drive torque will undershoot after the shift mode is switched, and in this case, the driver will also feel uncomfortable. .

A first aspect of the present invention provides an automatic shift mode for solving the problem that the relational characteristic between the accelerator pedal operation amount and the engine output during the manual shift mode is different for each selected shift speed. In order to eliminate the problem of overshoot shock and undershoot of the drive shaft torque at the time of switching from the automatic shift mode to the manual shift mode, which is inevitable when the target engine torque is individually obtained in the manual shift mode and the manual shift mode as described above. In addition, when the vehicle shifts from the automatic transmission mode to the manual transmission mode, the driving force of the vehicle enables the engine output control to change the drive shaft torque, not the engine torque, from the value before the transition to the value after the transition with an arbitrary response. The purpose is to propose a control device.

A second aspect of the present invention provides a method for calculating a target engine torque for shifting to a manual shift mode for the purpose of realizing the solution of the problem in the first aspect of the present invention more reliably. Aim.

[0013] A third aspect of the present invention is to make the target engine torque for shifting to the manual transmission mode appropriate irrespective of the intake delay of the engine so as to further ensure the above-described shock countermeasures. I do.

According to a fourth aspect of the present invention, unlike the first aspect, at the time of transition from the automatic transmission mode to the manual transmission mode, the engine torque is changed from a value before the transition to a value after the transition from the automatic transmission mode. It is an object of the present invention to enable the engine output control to be changed in accordance with the shift response of the vehicle and to solve the problem regarding the overshoot and undershoot of the drive shaft torque.

A fifth aspect of the present invention is directed to propose an effective method for calculating a target engine torque for shifting to a manual shift mode in the fourth aspect.

A sixth object of the present invention is to allow the calculation of the target engine torque for shifting to the manual shift mode in the fourth invention to be performed in a simpler and less computational manner.

[0017]

To achieve the above object, a vehicle driving force control apparatus according to a first aspect of the present invention comprises an engine capable of arbitrarily changing the output by factors other than the operation of an accelerator pedal, and a continuously variable transmission. In a vehicle equipped with a power train combined with the above, in the automatic transmission mode, after the required drive shaft torque is obtained based on at least the accelerator pedal operation amount, the automatic transmission mode is determined based on the required drive shaft torque and the drive system gear ratio. Calculate the target engine torque for
The output of the engine is controlled so as to attain this target value. In the manual shift mode, the required engine torque is obtained based on at least the accelerator pedal operation amount. A target engine torque for shifting to the manual transmission mode, which changes with a predetermined phase delay from the driving shaft torque toward a target transmission shaft torque for the manual transmission mode corresponding to the required engine torque, is calculated. The output of the engine is controlled, and after the target engine torque for shifting to the manual shift mode converges to the required engine torque, the engine output is controlled to become the required engine torque. .

According to a second aspect of the present invention, there is provided a driving force control apparatus for a vehicle.
In the first aspect, when calculating the target engine torque for shifting to the manual shift mode, a filter corresponding to the predetermined phase delay is used, and a drive system corresponding to the required engine torque and a set speed ratio in the manual shift mode is used. The target drive shaft torque for the manual transmission mode is obtained by multiplication with a gear ratio and input to the filter, and the required drive shaft torque for the automatic transmission mode immediately before shifting from the automatic transmission mode to the manual transmission mode is calculated by the filter. The target drive shaft torque for shifting to the manual transmission mode is obtained by the filter processing that sets the output to the initial value.
The target engine torque for shifting to the manual transmission mode is obtained by dividing the target drive shaft torque for shifting to the manual transmission mode by the actual transmission ratio of the drive system.

A vehicle driving force control device according to a third aspect of the present invention
In the first invention or the second invention, the target engine torque for shifting to the manual shift mode is subjected to a phase advance compensation for compensating for an intake delay of an engine, thereby contributing to the engine output control. It is.

The driving force control apparatus for a vehicle according to the fourth aspect of the present invention relates to a vehicle equipped with a power train which is a combination of an engine whose output can be arbitrarily changed by factors other than the operation of the accelerator pedal and a continuously variable transmission. In the automatic transmission mode, the required drive shaft torque is obtained based on at least the accelerator pedal operation amount, and then the target engine torque for the automatic transmission mode is calculated from the required drive shaft torque and the drive system gear ratio. In the manual shift mode, the engine output is controlled, and in the manual shift mode, the required engine torque is obtained based on at least the accelerator pedal operation amount, and immediately after shifting from the automatic shift mode to the manual shift mode, the engine torque is set to the target for the automatic shift mode. Shift response delay of the continuously variable transmission from engine torque to the required engine torque A target engine torque for shifting to the manual shift mode for changing with a phase delay corresponding to the above is calculated, and the output of the engine is controlled so as to attain the target value. After the torque has converged, the engine output is controlled to be the required engine torque.

A vehicle driving force control apparatus according to a fifth aspect of the present invention
In the fourth invention, when calculating the target engine torque for shifting to the manual transmission mode, a filter modeling a shift response delay characteristic of the continuously variable transmission is used, and the input of the filter is set to the required engine torque, and the input of the filter is set to the required engine torque. The filter output obtained by the filter calculation using the output initial value as the target engine torque for the automatic shift mode immediately before shifting from the automatic shift mode to the manual shift mode is set as the target engine torque for shifting to the manual shift mode. It is.

A vehicle driving force control device according to a sixth aspect of the present invention
In the fourth invention, when calculating the target engine torque for shifting to the manual shift mode, the gear ratio of the continuously variable transmission in the automatic shift mode immediately before shifting from the automatic shift mode to the manual shift mode, and shifting to the manual shift mode The current gear ratio internally divides between the gear ratio in the later manual gear shift mode and the gear ratio according to the internal gear ratio,
The automatic transmission mode target engine torque immediately before shifting from the automatic transmission mode to the manual transmission mode, and a torque value that internally divides the required engine torque into the manual transmission mode transition target engine torque. It is a feature.

[0023]

According to the first aspect of the present invention, the continuously variable transmission changes the speed of rotation from an engine whose output can be changed by factors other than the operation of the accelerator pedal, transmits the rotation, and runs the vehicle.
During this time, when the continuously variable transmission is in the automatic transmission mode, the drive force control device determines the required drive shaft torque based on at least the accelerator pedal operation amount, and then performs the automatic transmission based on the required drive shaft torque and the drive system gear ratio. The target engine torque for the mode is calculated, the output of the engine is controlled so as to reach this target value, and if the continuously variable transmission is in the manual shift mode, the required engine torque is obtained based on at least the accelerator pedal operation amount. Control the engine output to achieve engine torque.

As described above, in the automatic transmission mode, the engine torque corresponding to at least the required drive shaft torque obtained based on the accelerator pedal operation amount is used as the target engine torque for the automatic transmission mode. Unlike the target engine torque for the manual shift mode, at least the requested engine torque obtained based on the accelerator pedal operation amount is different from the target engine torque for the manual shift mode. It is possible to eliminate a sense of incongruity that the selected gear is different.

In the first aspect of the invention, the drive shaft torque is changed from the required drive shaft torque to the target drive shaft torque for the manual shift mode corresponding to the required engine torque immediately after the shift from the automatic transmission mode to the manual transmission mode. The target engine torque for shifting to the manual shift mode that changes with a predetermined phase delay toward the target is calculated, and the output of the engine is controlled so that the target value is obtained. Therefore, when shifting from the automatic shift mode to the manual shift mode,
The drive shaft torque, not the engine torque, corresponds to the predetermined phase delay from the value before the shift (the required drive shaft torque) to the value after the shift (the target drive shaft torque for the manual transmission mode corresponding to the required engine torque). It is possible to control the engine output to be changed by an arbitrary response, and it is possible to guarantee that the drive shaft torque changes with the above-mentioned predetermined phase delay when shifting from the automatic shift mode to the manual shift mode, and to change the engine torque in the shift. FIG. 9 shows a case where an attempt is made to change from a previous value to a value after transition with a predetermined phase delay.
As described above, there is no problem regarding the overshoot and undershoot of the drive shaft torque generated as described above, and further, the change response of the drive shaft torque can be arbitrarily set according to the driver's preference, and Nevertheless, it has an excellent feature that the above-mentioned effects are not inhibited at all.

In the second invention, the calculation of the target engine torque for shifting to the manual shift mode is performed as follows. That is, in the calculation, the filter corresponding to the predetermined phase delay in the first invention is used, and the manual transmission mode is calculated by multiplying the required engine torque by the drive system transmission ratio corresponding to the set transmission ratio in the manual transmission mode. A target drive shaft torque is obtained as input to the filter, and the required drive shaft torque for the automatic shift mode immediately before shifting from the automatic shift mode to the manual shift mode is set to an initial output value of the filter by a filter process. The target drive shaft torque for shifting to the mode is determined, and the target engine torque for shifting to the manual transmission mode is determined by dividing the target drive shaft torque for shifting to the manual transmission mode by the actual drive system gear ratio.

In this case, since the target engine torque for shifting to the manual shift mode is determined by a generally established filter process, an effective method of calculating the target engine torque for shifting to the manual shift mode is proposed. Further, since the initial value of the output of the filter is the required drive shaft torque for the automatic shift mode immediately before the shift from the automatic shift mode to the manual shift mode, the drive shaft is switched when the automatic shift mode is switched to the manual shift mode. Since the torque changes from the required drive shaft torque for the automatic transmission mode immediately before the switching to the target drive shaft torque for the manual transmission mode, smooth switching can be compensated.

In the third invention, the target engine torque for shifting to the manual shift mode is applied to the engine output control by performing the phase advance compensation for compensating the intake delay of the engine to the target engine torque for shifting to the manual shift mode. Is appropriate regardless of the intake delay of the engine, and the problem of the shock caused by the overshoot or undershoot of the drive shaft torque can be surely realized regardless of the intake delay of the engine.

In the fourth aspect of the present invention, the continuously variable transmission changes the speed of rotation from an engine whose output can be changed by a factor other than the operation of the accelerator pedal, transmits the rotation, and runs the vehicle. During this time, when the continuously variable transmission is in the automatic transmission mode, the drive force control device determines the required drive shaft torque based on at least the accelerator pedal operation amount, and then performs the automatic transmission based on the required drive shaft torque and the drive system gear ratio. The target engine torque for the mode is calculated, the output of the engine is controlled so as to reach this target value, and if the continuously variable transmission is in the manual shift mode, the required engine torque is obtained based on at least the accelerator pedal operation amount. Control the engine output to achieve engine torque.

As described above, in the automatic transmission mode, the engine torque corresponding to at least the required drive shaft torque obtained based on the accelerator pedal operation amount is used as the target engine torque for the automatic transmission mode. Unlike the target engine torque for the manual shift mode, at least the requested engine torque obtained based on the accelerator pedal operation amount is different from the target engine torque for the manual shift mode. It is possible to eliminate a sense of incongruity that the selected gear is different.

In the fourth aspect of the invention, the engine torque is changed from the target engine torque for the automatic shift mode to the manual shift mode immediately after the shift from the automatic shift mode to the manual shift mode, particularly, immediately after the shift from the automatic shift mode to the manual shift mode. Calculates the target engine torque for shifting to the manual transmission mode to change with a phase delay corresponding to the shift response delay of the continuously variable transmission toward the required engine torque for the shift mode, and outputs the engine so that the target value is obtained. Therefore, the change in the target engine torque for shifting to the manual transmission mode can be completely matched with the shift response delay of the continuously variable transmission, and the engine torque is reduced from the target engine torque for the automatic transmission mode to the required engine for the manual transmission mode. Engine output that varies with torque As described above, the target engine torque change becomes steep with respect to the shift response delay characteristic of the continuously variable transmission during the transition from the automatic shift mode to the manual shift mode, causing a shock due to the overshoot of the drive shaft torque. This does not cause a problem such as the occurrence of a shock due to undershoot of the drive shaft torque.

In the fifth invention, the target engine torque for shifting to the manual transmission mode in the fourth invention is calculated as follows. In other words, a filter that models the shift response delay characteristics of the continuously variable transmission is used, the input of the filter is set to the required engine torque, and the output initial value of the filter is set to the automatic shift immediately before shifting from the automatic shift mode to the manual shift mode. The filter output by the filter calculation using the target engine torque for the mode is set as the target engine torque for shifting to the manual shift mode. In this case, since the target engine torque for shifting to the manual transmission mode is obtained by a generally-established general method of filter processing, an effective method of calculating the target engine torque for shifting to the manual transmission mode is proposed.

In the sixth invention, the target engine torque for shifting to the manual transmission mode in the fourth invention is calculated as follows. That is, the current gear ratio is set between the gear ratio of the continuously variable transmission in the automatic gear shift mode immediately before the shift from the automatic gear shift mode to the manual gear shift mode and the gear ratio in the manual gear shift mode after the gear shift to the manual gear shift mode. In accordance with the internal ratio of the internal gear ratio, the manual shift mode shifts with a torque value that internally splits between the target engine torque for the automatic shift mode immediately before shifting from the automatic shift mode to the manual shift mode and the required engine torque. Target engine torque.

In this case, since the target engine torque for shifting to the manual transmission mode is calculated so as to match the actual shift response of the continuously variable transmission, when the shift response of the continuously variable transmission changes complicatedly. In this case, the target engine torque for shifting to the manual shift mode can be surely matched with the shift response delay characteristic. Further, according to the calculation method, the calculation is simpler than using a filter, and the calculation load is reduced. Can be.

[0035]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a power train of a vehicle provided with a driving force control device according to an embodiment of the present invention. The power train includes an engine 1, a continuously variable transmission 2, and a torque interposed therebetween. Converter 3
And a final drive gear set 5 between the continuously variable transmission 2 and the drive wheels 4.

The engine 1 includes an air cleaner 6 and a throttle valve 7 in an intake system and an exhaust purification catalyst 8 in an exhaust system. The throttle valve 7 is linked to an accelerator pedal (not shown) operated by a driver. An electronically controlled throttle valve that is not connected but disconnected therefrom and whose opening is electronically controlled by a step motor 9. Here, the output of the engine 1 is controlled by factors other than the operation of the accelerator pedal by controlling the opening of the throttle valve 7 via the step motor 9, and the engine output control is performed by controlling the fuel injection amount and the ignition timing. Can also be performed.

The continuously variable transmission 2 is a known V-belt type continuously variable transmission, and has a primary pulley 11 which is drivingly connected to an output shaft of the engine 1 via a torque converter 3 and is aligned in a plane perpendicular to the shaft. With the secondary pulley 12 arranged,
And a V-belt 13 stretched between these pulleys. The driving wheels 4 are drivingly connected to the secondary pulley 12 via the final drive gear set 5 described above.

To change the speed of the continuously variable transmission 2, the V of each of the primary pulley 11 and the secondary pulley 12 is changed.
Of the flanges forming the groove, one movable flange is relatively close to the other fixed flange to reduce the width of the V-groove, or to separate the movable flange so that the width of the V-groove can be increased. The V-groove width of the primary pulley 11 is reduced (widened) by a speed change actuator not shown.
At times, the V-groove width of the secondary pulley 12 is displaced so as to be widened (narrowed), so that the continuously variable transmission 2 can be continuously variablely shifted so that the actual speed ratio matches the speed ratio command.

The above-described engine output control and shift control are performed by a controller, and this controller, as shown in FIG.
PU) 21, a read-only memory (ROM) 22,
A random access memory (RAM) 23, an input port 24, an A / D converter 25, and an output port 26 are correlated as shown in the figure. The input port 24 includes an accelerator sensor 31 for detecting an accelerator pedal depression amount APS, a throttle opening sensor 32 for detecting an opening TVO of the throttle valve 7, a vehicle speed sensor 33 for detecting a vehicle speed VSP, and a driver. a mode switch 34 when selecting a shift mode, to connect the engine speed sensor 35 for detecting the engine speed N _e. The output port 26 corresponds to a throttle opening command 36 to the step motor 9, a speed ratio command 37 to the continuously variable transmission 2, a fuel injection signal 38 to the engine 1, and other control signals. Output to the actuator.

The controller (CPU) determines a gear ratio command 37 to control the speed of the continuously variable transmission 2 in a known manner based on the input information and issues a command to the continuously variable transmission 2. It is assumed that the control program of FIG. 3 is repeatedly executed by a periodic interruption of, for example, 10 msec, and the driving force control (engine output control) targeted by the present invention is performed as follows. First, at step 401, it is determined whether the current shift mode is an automatic shift mode (manual shift mode).
Check. In the automatic shift mode, in step 402, the accelerator pedal depression amount APS and the vehicle speed V
From the SP, a required drive shaft torque TdD desired by the driver is obtained by a known map search or calculation.

Next, at step 403, the required drive shaft torque TdD is divided by the drive system speed ratio which is a product of the speed ratio GM of the continuously variable transmission 2 and the final speed reduction ratio Gf (speed reduction ratio of the final drive gear set 5). To obtain the target engine torque TeA for the automatic transmission mode,
04, the automatic transmission mode target engine torque T
Engine output control is performed so that eA is achieved. The engine output control can be performed by throttle opening control, in which the opening of the throttle valve 7 is controlled by the step motor 9, fuel injection amount control, ignition timing control, and the like. Then, in step 405, the required drive shaft torque TdD in step 402 is stored as a previous required drive shaft torque value TdDold used in engine output control when shifting to the manual shift mode described below.

[0042] In step 406 when determining that the manual shift mode in step 401, the known map search from the accelerator pedal depression amount APS and the engine speed N _e, or by calculation, the required engine torque TeD the driver wants And then step 40
At 7, it is determined whether or not the previous time was the automatic shift mode. When it is determined that the shift mode is the automatic shift mode, that is, when it is determined that the shift has been made to the manual shift mode this time, the transient engine output control at the time of the shift is performed as follows.

In step 408, the control execution flag Fstart after the shift to the manual shift mode is set, and in step 409, the initial value of the output of the filter used when obtaining the target gear ratio for shifting to the manual shift mode is set in step 405 as described later. Is the last required drive shaft torque value TdDold stored last, that is, the required drive shaft torque for the automatic transmission mode immediately before the shift from the automatic transmission mode to the manual transmission mode. Note that these steps 408 and 409 are executed only once immediately after the shift from the automatic shift mode to the manual shift mode.

Next, at step 410, the required engine torque TeD at step 406 is multiplied by the drive system gear ratio in the manual gear shift mode, which is the product of the set gear ratio GM 'in the manual gear shift mode and the final reduction ratio Gf. Target drive shaft torque for manual shift mode (T
eD · GM ′ · Gf), which is used as the input of the filter. In step 411, the target drive shaft torque for manual shift mode (TeD · GM ′ ·
A filter output is obtained by the following filter operation using Gf) as an input.

Here, the target drive shaft torque (TeD, GM ', G) for the manual transmission mode is filtered by the above filter.
f) will be described in detail when a predetermined first-order delay described later is achieved, for example, when the predetermined first-order delay is a delay with a time constant of 1 sec. The filter uses a differential operator s to obtain 1 / (s + 1). ), Which is expressed as discrete time using a leading operator z with a sampling time of 10 msec, 0.00497512 (z + 1) / (z-0.990)
04975), and the filter output y (k) of this time (k) is
-1) filter output y (k-1) and this time filter input
It can be calculated from the following equation from u (k) and the previous filter input u (k-1). y (k) = 0.99004975y (k-1) +0.00497512 ｛u (k) + u (k-1)｝ (1) However, the initial value of the previous filter output y (k-1) is a step According to 409, the last required drive shaft torque value TdDold lastly stored in step 405, that is, the required drive shaft torque for the automatic transmission mode immediately before the shift from the automatic transmission mode to the manual transmission mode, is used as the previous filter input u (k− The initial value of 1) is set as the drive shaft torque corresponding to the required engine torque TeD first determined in step 406 immediately after the shift from the automatic shift mode to the manual shift mode, and the current filter input u (k) is determined in step 410. The obtained instantaneous manual shift mode target drive shaft torque (TeD · GM ′ · Gf) is used.

In the next step 412, the filter output y (k) obtained by the above calculation is used as the target drive shaft torque TeDS for shifting to the manual transmission mode. In step 413, the target drive shaft torque TeDS for shifting to the manual transmission mode is calculated. The target engine torque T for shifting to the manual transmission mode is obtained by dividing the actual transmission ratio, which is a product of the actual transmission ratio GM of the continuously variable transmission 2 and the final reduction ratio Gf, by the driving system actual transmission ratio.
eDS / (GM · Gf) is obtained.

Here, the above-mentioned predetermined first-order lag characteristic of the filter in step 411 is determined by the target drive shaft torque T for shifting to the manual shift mode, which is obtained in step 412.
The eDS is calculated from the required drive shaft torque TdDold for the automatic transmission mode immediately before the shift to the manual transmission mode set in step 405 and the target drive shaft torque (TeD · G) for the manual transmission mode obtained in step 410.
M ′ · Gf), which can be changed with a predetermined phase delay desired by the driver, whereby the target drive shaft torque TeDS for shifting to the manual shift mode can be changed in any response to the drive shaft torque before shifting to the shift mode. The drive shaft torque (TeD · GM ′ · Gf) after the transition from TdDold is set.

When the target engine torque TeDS / (GM · Gf) for shifting to the manual transmission mode is directly used as a target value for engine output control, the actual engine torque is transiently reduced due to intake delay in the engine. Since the target engine torque TeDS / (GM · Gf) cannot be matched and an error occurs, in step 414, the target engine torque TeDS / (G
M · Gf) is subjected to phase lead compensation.

In the phase lead compensation, a case where the intake delay of the engine is a first-order delay of 0.3 sec in time constant will be described. A filter for modeling this first-order delay characteristic and compensating for the intake delay of the engine is (0.3 s +1)
/(0.05s+1), which is expressed in discrete time using a leading operator z with a sampling time of 10 msec, is expressed as (5.54545454z-5.36363636) / (z-0.81818181)
Therefore, the filter output y (k) of this time (k) is
1) filter output y (k-1) and this time filter input u
(k) and the previous filter input u (k-1) can be calculated by the following equation. y (k) = 0.81818181y (k-1) + 5.54545454u (k) -5.36363636u (k-1) ・ ・ ・ (2)

At step 415, the output of the filter, that is, the target engine torque for shifting to the manual shift mode after compensating for the intake delay of the engine, is calculated as the target engine torque T for shifting to the manual shift mode with the intake delay compensated.
In step 416, the engine output is controlled so as to become TeMS. In step 417, the target engine torque TeMS for shifting to the manual shift mode with intake delay compensation is stored as the previous value TeMSold, and is stored in the following table. As described above, it contributes to the determination of whether or not the shift to the manual shift mode has been completed.

In this determination, in step 418, which is selected when it is determined in step 407 that the manual transmission mode was also the last time, the previous value TMS of the target engine torque TeMS for shifting to the intake delay compensated manual transmission mode is selected.
When the eMSold determines that the required engine torque TeD in step 406 has converged until the absolute value of the difference between them becomes less than the set value α, and while the convergence state continues, the convergence is incremented in step 419. When it is determined in step 421 that the determination counter Cend has exceeded the set value β, it is determined that the shift to the manual shift mode has been completed.

In step 418, | TeMSold-T
While it is determined that eD | ≧ α, after resetting the convergence determination counter Cend to 0 in step 420,
Even if | TeMSold-TeD | <α, the control to the manual shift mode is not completed as long as it is determined in step 421 that this state does not continue for the time Cend> β. Steps 410-4
Proceeding to a loop of 17, the transitional engine output control for shifting to the manual shift mode is performed.

| TeMSold-TeD | <α
Is continued for the time of Cend> β, the shift to the manual shift mode has been completed, and in steps 422 to 425, the convergence determination counter Cend
Is reset to 0, the control execution flag Fstart after shifting to the manual shift mode is reset, the required engine torque TeD obtained in step 406 is set to the target engine torque TeM for the manual shift mode, and the engine torque becomes the target value TeM. To control the output of the engine.

According to the present embodiment having the above configuration,
During the automatic shift mode, in steps 402 to 404, the accelerator pedal depression amount APS and the vehicle speed VS
The target engine torque TeA for the automatic transmission mode is calculated by dividing the required drive shaft torque TdD obtained from P by the drive system gear ratio (GM · Gf), and the output of the engine is controlled so as to reach this target value. In the case of the shift mode, steps 406, 407, 418, 419, 4
In steps 21 to 425, the accelerator pedal depression amount AP
Since the driver S and the engine speed N _e is the manual shift mode for the target engine torque TeM seeking required engine torque TeD desired, to control the engine output so as to be the target (required) engine torque, that is, manual In the shift mode, the target engine torque T
Unlike automatic shift mode eM, because it was decided to Ategau required engine torque TeD determined from the accelerator pedal depression amount APS and the engine speed N _e, the accelerator pedal depression amount APS during running of the manual shift mode and the engine torque ( It is possible to eliminate a sense of incongruity that the characteristic of the relationship with (output) differs for each selected shift speed.

In particular, immediately after the shift from the automatic shift mode to the manual shift mode, in steps 406 to 417, the drive shaft torque is changed to the required drive shaft torque TdDold for the automatic shift mode immediately before the shift (step 40).
5, 409) toward the target drive shaft torque for manual transmission mode (TeD, GM ', Gf in step 410) corresponding to the required engine torque TeD (step 406) (the filter processing in step 411) ), The target drive shaft torque TeDS for shifting to the manual shift mode is determined, and the target drive shaft torque TeDS is divided by the actual drive system gear ratio (GM · Gf) to obtain the engine torque for shifting to the manual shift mode TeDS / (GM · Gf) is obtained (step 41)
3) Since this contributes to the engine output control (step 416), it is possible to guarantee that the drive shaft torque changes with the above-mentioned predetermined phase delay when shifting from the automatic transmission mode to the manual transmission mode. Is not changed from the value before the shift to the value after the shift with a predetermined phase delay, without causing the problem relating to the overshoot and undershoot of the drive shaft torque generated as described above with reference to FIG. At this time, there is an excellent feature that the change response of the drive shaft torque can be arbitrarily set according to the driver's preference, and nonetheless, the above-mentioned effects are not impaired at all.

The predetermined phase delay (step 41)
As shown in FIG.
Shift from automatic transmission mode to manual transmission mode
Instant t ₁After that, the actual gear ratio is set to the manual gear mode.
The instant t when the gear ratio is reached_TwoJust the manual shifting mode
Target engine torque TeDS / (GM · Gf)
Is the required engine torque TeD in the manual shift mode.
So that the drive shaft torque
The manual transmission mode for the target drive shaft torque (step
410 TeD, GM ', Gf)
Is possible, and is clear from the drive shaft torque waveform shown in FIG.
Shift from automatic shift mode to manual shift
Switching to the mode can even be realized.

In steps 418 to 421,
Target engine torque TeM for shifting to manual shift mode
It is determined that the previous value TeMSold of S has converged to the required engine torque TeD in step 406 until the absolute value of the difference between the two becomes less than the set value α, and the convergence for measuring the duration of this convergence state Judgment counter Ce
When it is determined that nd becomes Cend> β, it is determined that the shift to the manual shift mode has been completed, and the transient control of the engine (steps 406 to 417) is ended. Therefore, it is possible to avoid a problem that the transient control is performed unnecessarily forever.

In this embodiment, the required engine torque TeD and the set speed ratio G in the manual speed change mode are set.
The target drive shaft torque for manual transmission mode (Te) is multiplied by the drive system gear ratio (GM ′ · Gf) corresponding to M ′.
D · GM ′ · Gf) is obtained (step 410), and is processed by a filter having a predetermined arbitrary first-order lag characteristic desired by the driver (step 411), and the target drive shaft torque TeDS (step 412) is obtained. Is divided by the actual drive gear ratio (GM · Gf) (step 413), and the target engine torque TeDS for shifting to the manual shift mode is set.
From the calculation of / (GM · Gf), the target engine torque for shifting to the manual transmission mode is determined by a generally established filter process, and the effective target engine torque for shifting to the manual transmission mode is calculated. System.

Further, at step 409, the initial value of the output of the filter is set to the required drive shaft torque TdDo immediately before the shift from the automatic shift mode to the manual shift mode.
ld, the drive shaft torque at the time of switching from the automatic transmission mode to the manual transmission mode is calculated from the required drive shaft torque value TdDold immediately before the switching from the target transmission shaft torque for the manual transmission mode (TeD ·
GM · Gf), and smooth switching can be compensated.

Note that the target engine torque TeDS / (GM · Gf) for shifting to the manual transmission mode is not used for the engine output control as it is, but in steps 414 and 415 phase advance compensation for compensating for the intake delay of the engine is performed. Since it contributes to output control, the target engine torque TeDS / (GM
Gf) is made appropriate irrespective of the intake delay of the engine, and the above-described problem of the shock due to the overshoot of the drive shaft torque can be surely realized regardless of the intake delay of the engine.

FIG. 5 shows another embodiment of the present invention. In this embodiment, step 405 of FIG.
In addition, step 409 is replaced with step 509, and steps 410 through 415 are replaced with steps 510-512, so that the conversion to the drive shaft torque is not performed at all when calculating the target engine torque for shifting to the manual transmission mode. . Therefore, in step 505,
The previous value TeAold of the automatic transmission mode target engine torque TeA determined in step 403 is continuously updated. In step 509, the previous automatic transmission mode target engine torque TeAold, that is, switching from the automatic transmission mode to the manual transmission mode. The target engine torque for the automatic transmission mode immediately before is used as the initial value of the output of the filter described below, and in step 510, the required engine torque TeD for the manual transmission mode obtained in step 406 is input to the filter.

The above filter changes the engine torque to the target engine torque TeA for the automatic transmission mode immediately before switching from the automatic transmission mode to the manual transmission mode.
The target engine torque TeMS for shifting to the manual transmission mode for changing from the old to the required engine torque TeD for the manual transmission mode with a phase delay corresponding to the shift response delay characteristic of the continuously variable transmission is obtained.
In step 511, the output of the filter is calculated.

Here, the above-mentioned filter will be described for the case where the shift response delay characteristic of the continuously variable transmission is a first-order delay of, for example, time constant T1s = 0.5 sec. 6 is represented by 1 / (T1s + 1) = 1 / (0.5s + 1) as indicated by 41. As shown in FIG. 6, the input of the filter is set to the instantaneous required engine torque TeD calculated in step 406, and the initial value of the output of the filter is set in step 509 from the automatic transmission mode to the manual transmission mode. By setting the target engine torque TeApld for the automatic transmission mode immediately before the switching, the filter output exhibits a time series change matching the transmission response delay characteristic of the continuously variable transmission as shown by the waveform in FIG.

Note that 1 / (T1s + 1) = 1 /
The filter 61 in FIG. 6 represented by (0.5s + 1) has a sampling time of 10 msec and is expressed in discrete time using the advance operator z, which results in 0.00990099 (z + 1) / (z-0.98019802). k) filter output y (k) is the previous (k-1)
Filter output y (k-1) and this time filter input u (k)
And the previous filter input u (k-1) can be calculated by the following equation. y (k) = 0.98019802y (k-1) +0.00990099 ｛u (k) + u (k-1)｝ (3) In this equation, the initial value of the filter output y (k-1) is stepped. 509 to TeAppl, filter input u
The initial value of (k-1) is switched from the automatic transmission mode to the manual transmission mode, and the required engine torque TeD first calculated in step 406, and the filter input u (k) is calculated from the instantaneously required engine calculated in step 406. By using the torque TeD, the filter output y (k) can be obtained.

At step 52, the filter output y (k) thus obtained is set as the target engine torque TeMS for shifting to the manual transmission mode, and at step 416, the engine output is controlled so as to become TeMS.

In this embodiment, since the filter models the shift response delay characteristic of the continuously variable transmission, the shift from the automatic shift mode to the manual shift mode is performed as shown in FIG. instant t ₁ after, the target engine torque TeMS for the manual shift mode transition
Can be changed so as to match the shift response delay of the continuously variable transmission indicated by the change over time in the actual gear ratio, and therefore, the instant when the actual gear ratio reaches the set gear ratio in the manual gear ratio mode. just t _2, it is possible to reach the target engine torque TeMS for manual shifting mode transition to the required engine torque TeD a manual shift mode.

Therefore, immediately after the shift from the automatic shift mode to the manual shift mode, as described above with reference to FIG. 9, the change in the target engine torque becomes steep with respect to the shift response delay characteristic of the continuously variable transmission, and the drive shaft torque is exceeded. It is possible to solve the problem that a shock is generated by the chute, and to realize a smooth switching from the automatic transmission mode to the manual transmission mode as is apparent from the drive shaft torque waveform shown in FIG.

In this embodiment, when the target engine torque TeMS for shifting to the manual transmission mode is determined, the drive shaft torque is filtered as in the above-described embodiment (steps 405, 409, 410, 4).
11, 412) Instead, the engine torque is filtered (steps 505, 509, 510, 511).
Therefore, the filter characteristic is regulated by the shift response delay, and cannot be set to any value as desired by the driver as in the above-described embodiment, but the filter characteristic is directly changed. In addition to being able to correspond to the shift response delay characteristic of the continuously variable transmission, it is easy to set the filter characteristic. In addition, conversion from engine torque to drive shaft torque (step 410) and conversion in the reverse direction (step 413 are unnecessary) As a result, the calculation becomes simpler, and the compensation for the intake delay of the engine (step 414) is not required. In this respect, there is an additional advantage that the calculation is simplified.

In the embodiment shown in FIG.
To find the target engine torque TeMS for speed mode transition
Instead of the above-mentioned filter processing (step 511)
Thus, it can be obtained by an operation as shown in FIG.
That is, first, from the automatic transmission mode to the manual transmission mode
Immediately before shifting to₁) In automatic transmission mode
The transmission ratio Gold of the continuously variable transmission and the manual transmission mode
Ratio G in manual shift mode after shifting to
m and the current actual gear ratio G is internally divided by the gear ratio d.
₁: D_TwoAsk for. Then, from the automatic transmission mode,
Automatic shift mode target immediately before shifting to the full shift mode
The engine torque TeAold and the manual transmission mode
Between the required engine torque TeD in
Speed ratio internal division ratio d₁: D_TwoSame ratio d as _Three: D_FourDivide by
Use the torque value to set the target
The gin torque is TeMS. Here, the manual transmission mode
The target engine torque for transition to the mode TeMS is expressed by the following equation.
Is done. TeMS = {(Gold-G) TeD- (G-Gm) TeAold} / (Gold-Gm) (4)

[0070] In this case also, the transition instant t ₁ after from the automatic shift mode to the manual shift mode, the manual shift mode for shifting to the target engine torque TeMS is that changes in conforms to the actual shift response delay of the continuously variable transmission Therefore, the actual speed ratio G is equal to the set speed ratio Gm in the manual speed mode.
Just instant t ₂ to reach, it is possible to reach the target engine torque TeMS for manual shifting mode transition to the required engine torque TeD a manual shift mode, it can achieve the same effect as in the embodiment described above . Further, according to the present embodiment, even when the shift response delay of the continuously variable transmission changes in a complicated manner, the target engine torque TeMS for shifting to the manual shift mode can always be surely matched with the shift response delay characteristic. Thus, the above operation and effect can be achieved when the shift response delay of the continuously variable transmission changes in any manner.

Further, according to the method of calculating the target engine torque TeMS for shifting to the manual shift mode according to the present embodiment, the calculation is simpler than using a filter, and the calculation load can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a power train of a vehicle equipped with a continuously variable transmission provided with a driving force control device according to an embodiment of the present invention.

FIG. 2 shows a configuration of a controller according to the embodiment;
It is a block diagram shown with the input / output signal system.

FIG. 3 is a flowchart showing an engine output control program for driving force control executed by a controller in the embodiment.

FIG. 4 is a time chart showing a temporal change of a target engine torque for shifting to a manual transmission mode for the engine output control.

FIG. 5 is a flowchart of an engine output control program similar to FIG. 3, showing another embodiment of the present invention.

FIG. 6 is an explanatory diagram of a filter used for obtaining a target engine torque for shifting to a manual transmission mode in the embodiment.

FIG. 7 is a time chart showing a temporal change of a target engine torque for shifting to a manual transmission mode for engine output control in the embodiment.

FIG. 8 is an explanatory diagram showing another calculation method of the target engine torque for shifting to the manual shift mode.

FIG. 9 is a time chart showing a change over time of a target engine torque for shifting to a manual shift mode when the target engine torque is obtained by a conventional general method.

[Explanation of symbols]

 Reference Signs List 1 engine 2 continuously variable transmission 3 torque converter 4 drive wheel 5 final drive gear set 6 air cleaner 7 electronic control throttle valve 8 exhaust purification catalyst 9 step motor 11 primary pulley 12 secondary pulley 21 central processing unit 22 read-only memory 23 random access Memory 24 Input port 25 A / D converter 26 Output port 31 Accelerator sensor 32 Throttle opening sensor 33 Vehicle speed sensor 34 Mode switch 35 Engine rotation sensor 36 Throttle opening command 37 Gear ratio command 38 Fuel injection signal 41 Filter

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 45/00 358 F02D 45/00 358C (72) Inventor Keisuke Suzuki 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan (72) Inventor Nobutaka Takahashi No. 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Nissan Motor Co., Ltd. F-term (reference) 3G084 AA03 BA02 BA05 BA11 BA17 DA05 DA08 DA18 EA04 EB12 FA00 FA10 FA33 3G093 AA06 BA03 BA15 CB04 DA01 DA06 DB00 DB05 EA05 EA09 EA13 EB03 EC02 FA02 FA07 FA10 3G301 HA06 JA03 JA04 KA11 LA01 LB00 NC02 ND02 PA11A PE01A PF01A PG00A

Claims (6)

[Claims] In a vehicle equipped with a power train which is a combination of an engine whose output can be arbitrarily changed by factors other than the operation of the accelerator pedal and a continuously variable transmission, at least an accelerator pedal operation amount is required in an automatic shift mode. After calculating the required drive shaft torque based on the above, a target engine torque for the automatic transmission mode is calculated from the required drive shaft torque and the drive system gear ratio, and the output of the engine is controlled to reach this target value. In the shift mode, the required engine torque is obtained based on at least the accelerator pedal operation amount, and immediately after shifting from the automatic shift mode to the manual shift mode, the drive shaft torque is changed from the required drive shaft torque to the manual shift mode corresponding to the required engine torque. That changes with a predetermined phase delay toward the target drive shaft torque Calculates a target engine torque for Al shift mode transition controls the output of the engine so that a target value,
A driving force control device for a vehicle, wherein after the target engine torque for shifting to the manual shift mode converges to the required engine torque, the engine output is controlled to be the required engine torque. 2. The method according to claim 1, wherein a filter corresponding to the predetermined phase delay is used to calculate the target engine torque for shifting to the manual shift mode, and the required engine torque and the set gear ratio in the manual shift mode are used. The target drive shaft torque for the manual shift mode is obtained by multiplication with the corresponding drive system speed ratio, and is used as an input to the filter. The required drive shaft torque for the automatic shift mode immediately before shifting from the automatic shift mode to the manual shift mode. A target drive shaft torque for shifting to the manual transmission mode is determined by a filter process that sets the target output shaft torque for shifting to the manual transmission mode by dividing the target drive shaft torque for shifting to the manual transmission mode by an actual drive system gear ratio. Configuration to determine the target engine torque for Driving force control apparatus for a vehicle according to. 3. The engine output control according to claim 1, wherein the target engine torque for shifting to the manual shift mode is subjected to a phase advance compensation for compensating for an intake delay of an engine. Driving force control device for a vehicle. 4. In a vehicle equipped with a power train that is a combination of an engine whose output can be arbitrarily changed by factors other than the operation of the accelerator pedal and a continuously variable transmission, at least the accelerator pedal operation amount is required in the automatic transmission mode. After calculating the required drive shaft torque based on the above, a target engine torque for the automatic transmission mode is calculated from the required drive shaft torque and the drive system gear ratio, and the output of the engine is controlled to reach this target value. In the shift mode, the required engine torque is obtained based on at least the accelerator pedal operation amount, and immediately after shifting from the automatic shift mode to the manual shift mode, the engine torque is continuously changed from the target engine torque for the automatic shift mode to the required engine torque. Manifold for changing with a phase delay corresponding to the shift response delay of the transmission Calculates a target engine torque for Al shift mode transition controls the output of the engine so that a target value,
A driving force control device for a vehicle, wherein after the target engine torque for shifting to the manual shift mode converges to the required engine torque, the engine output is controlled to be the required engine torque. 5. The method according to claim 4, wherein the target engine torque for shifting to the manual transmission mode is calculated by using a filter that models a shift response delay characteristic of a continuously variable transmission, and inputting the filter to the required engine torque. And the filter output by the filter operation is set as the target engine torque for shifting to the manual shift mode, with the initial output value of the filter being the target engine torque for the automatic shifting mode immediately before shifting from the automatic shifting mode to the manual shifting mode. A driving force control device for a vehicle, comprising: 6. The transmission ratio of the continuously variable transmission in the automatic transmission mode immediately before transition from the automatic transmission mode to the manual transmission mode, when calculating the target engine torque for transition to the manual transmission mode, The target for the automatic transmission mode immediately before the transition from the automatic transmission mode to the manual transmission mode in accordance with the internal ratio of the current transmission ratio that internally divides between the transmission ratio and the transmission ratio in the manual transmission mode after the transition to the transmission mode. A driving force control device for a vehicle, wherein a target engine torque for shifting to a manual transmission mode is set using a torque value that internally divides between an engine torque and the required engine torque.