JPH09207628A - Control device for vehicle with continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict the decrease of drivability such as the occurrence of excessive engine brake when an acceleration pedal is reset. SOLUTION: A control device consists of a gear ratio changing means 201 to change a gear ratio for a continuously variable transmission, a shift control means 200 to compute a target gear ratio corresponding to the driving condition of a vehicle and control the gear ratio changing means 201 in accordance with the target gear ratio, an engine control means 202 to control an engine corresponding to the driving condition of the vehicle and an engine torque reducing means 203 to reduce engine torque corresponding to the driving torque of the continuously variable transmission.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a control device for controlling an engine and a transmission in a vehicle equipped with a continuously variable transmission.

[0002]

2. Description of the Related Art In a continuously variable transmission used for a vehicle, a vehicle speed Vsp and a throttle opening TVO (or an accelerator opening AC
Based on S), the target input shaft speed (target speed ratio) is determined.
No. 191360 is known.

When the accelerator pedal is released,
By maintaining the gear ratio for a predetermined time, the engine braking is tried to be effective.

[0004]

However, in the above-described conventional control device, when the accelerator pedal is released and the throttle opening TVO suddenly decreases from near full opening to fully closed, there is a problem that engine braking is too effective. However, on the other hand, when the accelerator pedal is depressed again from the fully closed position, the engine speed may increase excessively and the drivability may decrease.

Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to suppress excessive deterioration of drivability such as engine braking when the accelerator pedal is released.

[0006]

A first aspect of the present invention, as shown in FIG. 20, a gear ratio changing means 201 for changing the gear ratio of a continuously variable transmission, and a target gear ratio according to the operating condition of the vehicle. With a continuously variable transmission including a shift control means 200 for controlling the shift ratio changing means 201 in accordance with the target shift ratio and an engine control means 202 for controlling the engine in accordance with the driving state of the vehicle. The vehicle control device includes an engine torque reduction unit 203 that suppresses the engine torque according to the drive torque of the continuously variable transmission when the shift control unit 200 upshifts.

The second aspect of the present invention, as shown in FIG. 21, is a gear ratio changing means 20 for changing the gear ratio of a continuously variable transmission.
1 and the target gear ratio according to the driving state of the vehicle, and the gear ratio changing means 2 according to the target gear ratio.
In a control device for a vehicle with a continuously variable transmission, which includes a gear shift control unit 200 for controlling 01 and an engine control unit 202 for controlling an engine according to a driving state of the vehicle, an engine torque calculating unit 204 for calculating an engine torque.
An inertia torque calculation means 205 for calculating the inertia torque of the continuously variable transmission; a target drive torque calculation means 206 for calculating the target value of the drive torque by subtracting the inertia torque from the engine torque; and the shift control means 200. Drive torque determination means 207 for determining whether or not the detected value of the drive torque becomes larger than the target value when upshifted, and when the detected value of the drive torque becomes equal to or larger than the target value in this determination result. And an engine torque reducing means 203 for suppressing the engine torque.

In a third aspect based on the second aspect, the engine torque calculating means estimates the actual engine torque.

In a fourth aspect based on the second aspect, the inertia torque calculating means calculates the inertia torque based on a change in the target input speed of the continuously variable transmission.

[0010]

Therefore, according to the first aspect of the present invention, when the shift control means issues an upshift of the continuously variable transmission, the engine torque is suppressed in accordance with the drive torque of the continuously variable transmission. When the pedal is released for upshifting, the drive torque of the continuously variable transmission tries to temporarily increase in order to release its inertia torque as the engine speed decreases. By reducing the engine torque in accordance with the driving torque, it is possible to prevent the vehicle from accelerating due to inertia torque while performing an upshift in accordance with the driver's operation.

According to the second aspect of the invention, the target value of the drive torque is obtained by subtracting the inertia torque of the continuously variable transmission from the engine torque, and the detected value of the drive torque is the target value when the shift control means upshifts. When it becomes larger than the value, the engine torque is reduced. For example, when the driver releases the accelerator pedal to upshift,
As the engine speed decreases, the drive torque of the continuously variable transmission tries to temporarily increase in order to release its inertia, but the engine torque should be reduced according to the drive torque of this continuously variable transmission. Thus, it is possible to prevent the vehicle from being accelerated by the inertia torque while performing the upshift according to the operation of the driver.

Further, according to the third aspect of the invention, the target drive torque is calculated from the estimated actual engine torque, so that the control accuracy can be improved.

Further, according to the fourth aspect of the invention, since the inertia torque is calculated based on the change in the target input speed of the continuously variable transmission, the engine torque can be reduced quickly.
The control response can be improved.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, the continuously variable transmission 10 is set to a predetermined gear ratio according to the operating state of the vehicle by the gear ratio changing means 9 controlled by the gear shift controller 2. The step-variable transmission 10 is, for example, a toroidal type continuously variable transmission whose gear ratio can be changed according to the tilt angle of the power roller 18c (see FIG. 2).

On the other hand, the shift control controller 2 is connected to the engine control controller 3 which controls the ignition timing of the engine 1 and the fuel injection amount.

The engine 1 includes an accelerator pedal 12
In addition to the first throttle 4 that responds to the opening ACS of the second throttle 5, a second throttle 5 that is driven by the actuator 13 is provided, and the shift control controller 2 changes the opening TVO2 of the second throttle 5 according to the operating state. Torque control signal F
LGd is sent to the engine controller 3, and the engine controller 3 sends the second throttle 5 through the actuator 13 based on the second throttle opening TVO2.
The torque reduction control flag FLGd
The torque generated by the engine 1 is suppressed in accordance with the above.

The shift control controller 2 includes an accelerator opening TVO (or an opening ACS of the accelerator pedal 12) of the first throttle 4 and a crank angle sensor 8 from the engine 1 side.
While reading the engine speed Ne and the intake air amount Qa detected by, the shift position from a shift lever (not shown), the input shaft speed sensor 6 and the output shaft speed sensor 7 of the continuously variable transmission 10 and the output shaft speed Nt and the output. Shaft rotation speed No
3 and 10, the target input shaft speed tREV0 corresponding to the operating state is obtained from a preset shift map, and the step motor 61 of the gear ratio changing means 9 (see FIG. 2) is read. To the target gear ratio RTO and a control amount AST according to a torque shift compensation amount TS1 described later.
Command P.

The gear ratio changing means 9 is shown in FIG.
As shown in, the hydraulic actuator 50 that axially drives the trunnion shaft 50a that supports the power roller 18c of the continuously variable transmission 10, and the hydraulic actuator 50 that drives the step motor 61 and the trunnion shaft 50a is displaced.
A control valve 60 for supplying pressure oil to the main is configured.

The step motor 61 drives the spool 63 in response to a command from the shift control controller 2, and the oil chamber 50 above and below the piston 50P of the hydraulic actuator 50.
While the hydraulic pressure is supplied to and discharged from H and 50L, the displacement of the trunnion shaft 50a corresponding to the hydraulic pressure is fed back to the sleeve 64 which moves relative to the spool 63 via the tracing mechanism 67, and the hydraulic pressure to the hydraulic actuator 50 is transmitted. Adjusted.

As shown in the conceptual diagram of FIG. 3, the shift control controller 2 uses the vehicle speed Vsp and the throttle opening TVO (or accelerator opening ACS) as parameters to set the target input shaft speed tREV0 (see FIG. The gear ratio RTO is calculated from the medium Nin), the displacement amount of the spool 63 of the control valve 60 is determined from the no-load step table, and the control amount STP of the step motor 61 is determined according to this displacement amount.

On the other hand, in order to correct the torque shift of the continuously variable transmission 10 according to the input torque from the engine 1, FIG.
The torque shift compensation amount TS1 for the step motor 61 is calculated from the output characteristic of the engine 1 and the torque characteristic of the torque converter shown in FIG. 2 and the preset compensation step table in accordance with the gear ratio RTO. Target control amount DSRST calculated from TS1
The step motor 61 is driven according to P, and the tilt angle of the power roller of the continuously variable transmission 10 is set to a predetermined gear ratio while canceling the torque shift.

Regarding the compensation of the torque shift generated in the continuously variable transmission, Japanese Patent Application No.
Since it is performed in the same manner as -149085, etc., it will not be described in detail here.

Next, an example of control performed by the shift control controller 2 is shown in the flow charts of FIGS. 4 to 8, and an example of torque down control performed by the engine control controller 3 is shown in the flow chart of FIG. The controls of the controller 2 and the engine controller 3 will be described in detail. It should be noted that each flow chart is executed every predetermined time, for example, every 10 msec.

[Shift Control] FIG. 4 is a flow chart of the signal measuring unit for detecting the operating state of the vehicle. In step S1, the accelerator opening ACS is set as the operating state of the engine 1.
(Or throttle opening TVO), engine speed Ne,
While reading the intake air amount Qa and the like, the input shaft speed Nt and the output shaft speed No are read from the continuously variable transmission 10. Further, the torque control state signal RX is read from the engine controller 3.

In step S2, each value indicating the driving state of the vehicle is calculated. First, the vehicle speed Vsp is obtained by multiplying the output shaft rotational speed No by the conversion constant A.
The input shaft speed Nt measured this time and the previous input shaft speed N
The input shaft acceleration dNt is calculated from told. Further, from the input shaft speed Nt and the output shaft speed No, the gear ratio RTO
Similarly, the (actual gear ratio) is calculated from the input shaft speed Nt and the engine speed Ne, and the speed ratio e is calculated, and the value of the torque control state signal RX read in step S1 is substituted into the torque down control flag FLGd.

The torque down control flag FLGd
Indicates that the engine controller 3 is requested to reduce the torque when the value is 1, and when the torque control state signal RX is 1, the engine controller 3 indicates that the torque down control is being performed.

Next, the flow chart of FIG. 5 shows an outline of the shift control of the continuously variable transmission 10 and the engine 1 based on the operating state detected in steps S1 to S3.

The outline of this shift control is as follows: accelerator opening AC
From S (or the first throttle opening TVO1, the same applies below) and the vehicle speed Vsp, the target input shaft speed tRE of the continuously variable transmission 10 is calculated.
A target rotation speed calculation unit (step S4) for calculating V0,
A target driving force calculation unit (step S5) that calculates the target drive torque tTRQ, a torque control amount calculation unit (step S6) that calculates the target engine torque tTe, an opening TVO2 of the second throttle 5, and a torque down control flag. F
The engine control unit that calculates LGd (step S7), and the CVT that calculates the control amount (step number) ASTP of the step motor 61 according to the target control amount DSRSTP from the target input shaft speed tREV0 and the torque shift compensation amount TS1. It is composed of a control unit (step S8).

Then, the control amount ASTP of the step motor 61 for controlling the gear ratio of the continuously variable transmission 10 determined from the above steps S4 to S8 according to the operating condition, and the torque down control flag FLGd for controlling the torque generated by the engine 1 are controlled. ,
The second throttle opening TVO2 is sent to the step motor 61 and the engine control controller 3 at predetermined time intervals based on step S9 of the flowchart shown in FIG. 8, and in this step S9, the torque down control flag FLGd is set to the torque control. It is transmitted to the engine controller 3 after being assigned to the signal TX.

Next, the details of the shift control unit in steps S4 to S8 of FIG. 5 will be described below with reference to the flowcharts of FIGS.

First, step S40 in FIG.
Corresponding to the target rotation speed calculation unit, the vehicle speed Vsp and the accelerator opening ACS obtained by the signal measurement unit in FIG. 4 are used as parameters, and as shown in FIG. Search for tREV0.

Although FIG. 10 shows the shift map in the automatic shift mode, a shift map in the manual shift mode as shown in FIG. 15 may be used instead of the shift map. A predetermined target input shaft rotation speed tREV0 corresponding to a gear shift operation such as a shift switch is searched.

Then, the next step S50 is the above-mentioned FIG.
Corresponding to the target driving force calculation unit (step S5) of
As shown in FIG. 11, the vehicle speed Vsp and the accelerator opening ACS
Is used as a parameter to search for a target drive torque TRQ from a preset drive torque To map.

The next steps S60 and S61 correspond to the torque control amount calculation section. First, in step S60, the input shaft acceleration dNt and the gear ratio RTO obtained in step S3 are set, and the preset stepless speed is set. From the inertia constant It around the input shaft of the transmission 10, the inertia torque Tins converted into the output shaft of the continuously variable transmission 10 is calculated by the following equation.

Tins = dNt × It × RTO In step S61, the target engine torque tTe is calculated by subtracting the inertia torque Tins from the target drive torque tTRQ obtained in step S50.

TTe = (tTRQ-Tins) / RTO That is, the target engine torque tTe is the acceleration dNt which is the rate of change of the input shaft speed Nt of the continuously variable transmission 10.
Estimate the output shaft converted inertia torque Tins from
It becomes the value obtained by subtracting the inertia torque Tins from the target drive torque tTRQ obtained in step S50.

Therefore, when the rotational speed of the engine 1 is reduced by releasing the accelerator pedal 12, the inertia torque Tins of the continuously variable transmission 10 is released to the drive shaft. The target engine torque in consideration of this inertia torque Tins is given. By controlling the torque generated by the engine 1 by tTe, the torque transmitted to the axle during deceleration can be accurately controlled.

Steps S70 to S73 are for calculating a command signal to the engine controller 3, and correspond to the engine control section of step S7.

First, the target engine torque tTe obtained in step S61 and the read engine speed Ne
The opening degree TVO2 of the second throttle 5 that adjusts the torque generated by the engine 1 is calculated from the opening degree TVO2 of the second throttle 5 and the opening degree TVO1 of the first throttle 4 (or accelerator opening degree ACS) in step S71. The first throttle opening TVO1 is compared with the second throttle opening TVO
If it is larger than 2, the process proceeds to step S73 to set 1 to the torque down control flag FLGd to request the engine control controller 3 to reduce the generated torque. On the other hand, if not, the torque down control flag FLGd is set at step S72. The second throttle opening TVO2 to be reset and sent to the engine controller 3 and the torque down control flag FLGd are set.

Next, steps S80 to 89 of FIG. 7 are CVT (continuously variable transmission) corresponding to step S8 of FIG.
First, in step S80, the target speed ratio tRTO is calculated from the target input shaft rotation speed tREV0 and the output shaft rotation speed No by the following equation.

TRTO = tREV0 / No Further, the control amount (the number of steps) STP of the step motor 61 for driving the spool 63 of the control valve 60 according to the target gear ratio tRTO, the no-load step table shown in FIG. Search more.

Next, at step S81, the torque Tin input to the continuously variable transmission 10 is estimated and calculated in order to calculate the torque shift compensation amount TS1.

This input torque Tin is determined by the above step S
Engine speed Ne, intake air amount Qa read in 1
An engine torque Te calculated from the first throttle opening TVO1 and a preset torque ratio t (e) of a torque converter (not shown) interposed between the continuously variable transmission 10 and the engine 1, Inertia constant It around the input shaft,
Then, the input shaft acceleration dNt obtained in step S3 is calculated based on the following equation.

Tin = Te (Ne, Qa) * t (e) -dNt * It In step S82, the compensation amount TS1 is calculated in order to correct the torque shift generated in the continuously variable transmission 10.

Here, as shown in FIG. 2, the torque shift generated in the toroidal type continuously variable transmission 10 depends on the input torque at the free end of the offset rotary shaft 50b that pivotally supports the power roller 18c. Since a vertical force is applied to the power roller 18 according to the elastic deformation of the rotary shaft 50b.
The tilt angle (actual gear ratio) of c also fluctuates, and this vertical force is also applied to the trunnion shaft 50a, and the trunnion shaft 50a is elastically deformed in the axial direction. The actual gear ratio fluctuates and deviates from the target gear ratio. In addition, the tilt angle of the power roller 18c also varies due to rattling of a bearing (not shown) that axially supports the power roller 18c.

The compensation amount TS1 necessary for correcting the torque shift of the continuously variable transmission 10 is the input torque T
It is calculated from the map of in and the target gear ratio tRTO (corresponding to the compensation step table shown in FIG. 3). It should be noted that this map is set in advance by experiments or the like, and the processing of step S82 constitutes the compensation loop shown by the broken line in FIG.

In step S83, the torque shift compensation amount TS1 thus obtained is added to the above-mentioned step S8.
Target gear ratio RT obtained from the no-load step table at 0
The control amount STP corresponding to O is added to obtain the target control amount DSRSTP of the step motor 61.

In steps S84 to S89, the control amount ASTP is calculated from the target control amount DSRSTP and the current control amount ASTP according to the response speed of the step motor 61, so that the target control amount DSRSTP is higher than the current control amount ASTP. When it is large, the control amount ASTP is increased to the target value DSRSTP by the control amount DSTP per unit time.

That is, in FIG. 12, assuming that the control amount of the step motor per unit time is DSTP, the control amount ASTP actually output to the step motor is the control amount D per unit time until the target control amount DSRSTP is reached.
The spool 63 of the control valve 60 drives the step motor 61 so as to achieve a predetermined gear ratio while canceling torque shift in real time by increasing or decreasing by STP.

In this way, the control amount ASTP of the step motor 61 obtained from the flowcharts of FIGS. 4 to 7 is output from the shift control controller 2 to the gear ratio changing means 9 in step S9 of the signal output section of FIG. , Continuously variable transmission 1
While setting the predetermined gear ratio RTO while canceling the torque shift of 0 in real time, the engine control controller 3 gives the torque control signal TX indicating the torque down control flag FLGd and the opening T of the second throttle 5.
VO2 is also sent out from step S9.

[Engine Control] The torque control signal T
The control contents of the engine controller 3 which have received the X and the second throttle opening TVO2 will be described below in detail with reference to the flowchart of FIG.

First, at step S90, it is judged from the torque control signal TX whether or not the torque down control flag FLGd is set to 1. If it is set to 1, the shift control controller 2 requests the torque down. If the torque down control flag FLGd is 0 while the routine proceeds to step S91 and thereafter, the counter CNT is reset to 0 in step S95, the process is terminated, and normal engine control (not shown) is performed. I do.

In step S91, the control current IM of the actuator 13 of the second throttle 5 is calculated from the map shown in FIG. 13 based on the second throttle opening TVO2 from the shift control controller 2, and the actuator 13 is driven. Then, the opening TVO2 of the second throttle 5 is set to a predetermined value.

Next, the counter CNT that sets the torque down control period by the throttle 92 is set to a predetermined threshold value CN.
If it is larger than Tth, and if it is larger than Tth, the torque down control is ended. Therefore, if it is equal to or smaller than the threshold value CNTth, the routine proceeds to step S93 to continue the torque down control.

In step S93, in order to reduce the torque generated by the engine 1, predetermined processing such as ignition timing retardation, fuel cut or fuel increase is performed.

Then, in step S94, the counter C
NT is incremented to a predetermined threshold value CNTth
The torque reduction control of step S93 is performed until, for example, the ignition timing retard is performed, and the generated torque of the engine 1 is reduced according to the torque reduction request based on the target engine torque tTe calculated by the shift control controller 2. It is.

[Operation] Thus, the shift control controller 2 drives the step motor 61 in accordance with the target gear ratio tRTO, and the target engine torque tTe obtained by subtracting the inertia torque Tins converted from the output shaft of the continuously variable transmission 10. Is calculated and the second throttle opening TVO2 for controlling the torque generated by the engine 1 according to the target engine torque tTe is set to the accelerator pedal 12 operated by the driver.
If the first throttle opening TVO1 is smaller than the first throttle opening TVO1 according to the above, torque down control is requested to the engine controller 3, and the torque generated by the engine 1 is suppressed by ignition timing retard, fuel cut, fuel increase, or the like.

Now, as shown in FIG. 14, the driver releases the accelerator pedal, and the first throttle opening TVO1 is fully opened (TVO = 8/8) to a medium opening (for example, 2 /
When closed to 8), the target gear ratio tRTO starts the upshift to the Hi side (small gear ratio) based on the gear shift map of FIG. 10 because the first throttle opening TVO1 decreases.

At this time, if the torque generated by the engine 1 is not suppressed, the inertia torque Tins is released in accordance with the decrease in the input shaft rotational speed Nt, so the torque transmitted to the drive shaft (the single axle in the figure). As shown by the solid line in the figure, the torque) increases immediately after the accelerator pedal 12 is released, and the driving torque that can suppress the acceleration of the vehicle in response to the release of the accelerator pedal 12 is indicated by the shaded area in the figure. An overshoot occurs and the vehicle accelerates against the driver's intention.

On the other hand, in the present embodiment, the inertia torque Tins converted into the output shaft is estimated from the change dNt in the input shaft speed of the continuously variable transmission 10 to obtain the target drive torque tT.
When the target engine torque tTe is obtained by subtracting the inertia torque Tins from RQ, when the accelerator pedal 12 is returned and the first throttle opening TVO1 becomes larger than the second throttle opening TVO2, the engine controller 3 is requested to perform torque down control. Then, the torque generated by the engine 1 can be quickly reduced by the ignition timing retard, fuel cut or fuel increase of the engine controller 3, and the engine torque and the drive torque are controlled as shown by the broken line in FIG. .

Therefore, according to the control of this embodiment,
When the input shaft rotation speed Nt is reduced and the inertia torque Tins is released by returning the accelerator pedal 12 from near full opening to near the intermediate opening degree, etc., while reducing the torque generated by the engine 1 to prevent vehicle acceleration, The gear ratio RTO can be upshifted to the Hi side in accordance with the decrease in the first throttle opening TVO1, and it becomes possible to ensure stable vehicle behavior by applying appropriate engine braking according to the driving intention. Unintentional engine braking that occurs when the accelerator pedal is released as in the conventional example and overblowing of the engine 1 when the pedal is stepped on again are eliminated, and the drivability of a vehicle equipped with a continuously variable transmission is eliminated. It is possible to improve.

In the above embodiment, the engine 1
As a means for controlling the torque generated by the accelerator pedal 1,
2 and the first throttle 4 and the actuator 13
Second controlled by the engine controller 3 via
Although the case where the throttle 5 is provided is shown, although not shown, the first throttle 4 is eliminated and the engine controller 3 drives the actuator 13 of the second throttle 5 according to the opening degree ACS of the accelerator pedal 12. The configuration may be adopted. In this case, the start of the torque down control can be determined by performing the comparison in step S71 from the opening ACS of the accelerator pedal 12 and the second throttle opening TVO2.

16 and 17 show the second embodiment,
A part of the flowchart showing the shift control unit shown in FIGS. 5 to 7 of the first embodiment is modified, and the other configuration is the same as that of the first embodiment.

FIG. 16 shows the shift control section of FIG. 5 including a target rotation speed calculation section (step S4), a torque control amount calculation section (step S15), and an engine control section (step S1).
6) and the CVT control unit (step S8), the target rotation speed calculation unit of step S4 and the step S8.
The CVT control unit of is similar to that of FIG.

FIG. 17 shows the details of the essential parts of the shift control section of FIG. 16 above. Step S150 corresponds to the torque control amount calculation section of above step S15, and step S160 and subsequent steps correspond to above step S16. explain.

First, in step S150, the inertia torque Tins converted into the output shaft of the continuously variable transmission 10 is obtained by multiplying the input shaft acceleration dNt obtained in step S3 of FIG. 4 and the inertia constant It around the input shaft.

Tins = dNt × It Then, in the engine control section of step S160,
From the preset engine output characteristic map as shown in FIG. 1, the first throttle opening TVO1 and the engine speed N
The current engine torque tTe0 is searched based on e.

In step S161, the target engine torque tTe is calculated by subtracting the inertia torque Tins obtained in step S150 from the current engine torque tTe0.

After step S162, the same as step S70 and after in FIG. 6, the opening TVO2 of the second throttle 5 is calculated from the target engine torque tTe and the engine speed Ne, and the first throttle opening is performed. Degree TVO1 and second throttle opening TVO2 are compared,
The first throttle opening TVO1 is the second throttle opening TV
When it becomes larger than O2, the torque down control flag FLG
d is set to 1 (steps S163 and S165).

Next, the shift control controller 2 uses the first
Similar to the embodiment, the torque down control flag FLGd and the second throttle opening TVO2 are sent to the engine control controller 3 to control the torque generated by the engine 1 according to the second throttle opening TVO2, while the accelerator pedal 12 is turned on. Return the first throttle opening TVO1 to TVO2.
If it becomes larger than this, the engine control controller 3 reduces the torque generated by the engine 1 by retarding the ignition timing or the like.

Therefore, the engine torque t in the operating state
The target engine torque t is obtained by estimating Te0 and subtracting the inertia torque Tins obtained from the input shaft acceleration dNt.
Since it is Te, it is possible to improve the control accuracy of the engine torque.

18 and 19 show the second embodiment,
A part of the flowchart showing the shift control unit shown in FIGS. 5 to 7 of the first embodiment is modified, and the other configuration is the same as that of the first embodiment.

FIG. 18 is a block diagram showing the shift control section of FIG. 5 including a target rotation speed calculation section (step S4), a CVT control section (step S8), a torque control amount calculation section (step S25), and an engine control section (step S7). ), The target rotation speed calculation unit in step S4, the CVT control unit in step S8, and the engine control unit in step S7 are the same as those in FIG.

FIG. 19 shows the details of the torque control amount calculator of FIG. 18, and steps S250 to S254 correspond to the torque control amount calculator of step S25 and will be described in detail below.

First, in step S250, the current actual target rotation speed tNt1 is stored in the previous value tNtold, and in step S251, the torque shift compensation amount TS1 is subtracted from the control amount ASTP of the step motor 61 (the value shown in FIG. 3). The actual target gear ratio tRTO1 is calculated from the control amount STP obtained from the load step table.

TRTO1 = iSTP (ASTP-TS
1) The control amount ASTP of the step motor 61 and the compensation amount T
S1 is obtained in steps S80 to S83 of the first embodiment.

Next, in step S252, the actual target speed ratio tRTO1 is multiplied by the output shaft speed No to calculate the actual target speed tNt1 of the input shaft, and in step S253, the actual target input shaft speed ratio tNt1. From step S250
The previous actual target input shaft rotational speed tNt1old stored in step 3 is subtracted to obtain the actual target rotational speed change amount dNt1.

DNt1 = tNt1-tNt1old Then, in step S254, the actual target rotational speed change amount dN.
The inertia torque Tins is obtained by multiplying t1 by the inertia constant It around the input shaft, and in step S7 of FIG. 18, the target drive torque tT is obtained as in the first embodiment.
The target engine torque tTe is obtained by subtracting the inertia torque Tins from RQ, and the second throttle opening TVO2 and the torque down control flag FLGd are obtained.
Is calculated.

Therefore, since the inertia torque Tins is obtained from the actual target rotation speed change amount dNt1, in addition to the effect of the first embodiment, it becomes possible to prevent the delay of the torque down control and the response of the control. Can be increased.

In the above embodiment, the case where the continuously variable transmission 10 is a toroidal type is shown, but although not shown, the same applies when a belt type continuously variable transmission is adopted.

The means for detecting or estimating the transient increase in the drive torque when the accelerator pedal 12 is released may be any means other than those described above. For example, although not shown, the accelerator pedal 12 is released. Sometimes, the control may be such that the drive torque does not increase.

[0083]

As described above, according to the first aspect of the present invention, when the shift control means commands the upshift of the continuously variable transmission, the engine torque is suppressed according to the driving torque of the continuously variable transmission. , When the driver releases the accelerator pedal to upshift, the drive torque of the continuously variable transmission tries to temporarily increase in order to release the inertia torque in accordance with the decrease in the engine speed. By reducing the engine torque according to the drive torque of the continuously variable transmission, the engine generated torque is reduced to prevent vehicle acceleration due to inertia torque, and the gear ratio is upshifted in response to accelerator pedal return operation. It is possible to secure the stable vehicle behavior by applying the appropriate engine braking according to the driving intention.
As in the conventional example, it is possible to prevent unintended engine braking that occurs when the accelerator pedal is returned, and overblowing of the engine when the pedal is stepped on again, and it is possible to improve the drivability of a vehicle equipped with a continuously variable transmission. It will be possible.

In the second aspect of the invention, a value obtained by subtracting the inertia torque of the continuously variable transmission from the engine torque is obtained as the target value of the drive torque, and the detected value of the drive torque is the target value when the shift control means upshifts. When it becomes larger than the value, the engine torque is reduced. For example, when the driver releases the accelerator pedal to upshift,
The drive torque of the continuously variable transmission tends to increase temporarily in order to release the inertia torque as the engine speed decreases, but the engine torque should be reduced according to the drive torque with this inertia torque added. Thus, while performing an upshift in response to the driver's accelerator pedal return operation, the vehicle can be prevented from accelerating due to inertia torque, and appropriate engine braking according to the driving intention can be applied to ensure stable vehicle behavior. Thus, it becomes possible to improve the drivability of the vehicle equipped with the continuously variable transmission.

Further, according to the third aspect of the present invention, the target drive torque is calculated from the estimated actual engine torque, so that the accuracy of the engine torque down control can be improved.

Further, in the fourth aspect of the invention, the inertia torque is calculated based on the change in the target input speed of the continuously variable transmission, so that the engine torque-down control can be rapidly changed, and The responsiveness can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram of a continuously variable transmission and an engine showing an embodiment of the present invention.

FIG. 2 is a conceptual diagram of gear ratio changing means.

FIG. 3 is a block diagram showing an outline of a shift control.

FIG. 4 is a flowchart showing an example of control performed by a shift control controller, showing a signal measuring unit.

FIG. 5 is a flowchart showing an example of control, showing an outline of a shift control unit.

FIG. 6 is a flow chart showing an example of control, which is a first half part showing details of a shift control section.

FIG. 7 is the latter half.

FIG. 8 is a flowchart showing an example of control, showing a signal output unit.

FIG. 9 is a flowchart showing an example of torque down control performed by the engine controller.

FIG. 10 is a shift map showing the relationship between the target input shaft speed Nt and the vehicle speed Vsp with the throttle opening TVO as a parameter.

FIG. 11 is a drive torque map showing the relationship between the drive torque To and the vehicle speed Vsp with the throttle opening TVO as a parameter.

FIG. 12 is a graph showing the relationship between the control amount ASTP of the step motor and time.

FIG. 13 is a map of second throttle opening and actuator control current.

FIG. 14 is an explanatory diagram showing an operation.

FIG. 15 is a shift map showing the manual mode, in which the target input shaft speed Nt and the vehicle speed Vsp are set with the shift speed as a parameter.
Shows the relationship.

FIG. 16 is a flowchart showing an outline of a shift control unit performed by the shift control controller according to the second embodiment.

FIG. 17 is a flow chart showing details of the main part of control in the same manner.

FIG. 18 is a flowchart showing an outline of a shift control unit performed by the shift control controller according to the third embodiment.

FIG. 19 is a flowchart showing details of a torque control amount calculation unit in the same manner.

FIG. 20 is a claim correspondence diagram corresponding to the first invention.

FIG. 21 is a claim correspondence diagram corresponding to any one of the second to fourth inventions.

[Explanation of symbols]

 1 Engine 2 Gear Change Control Controller 3 Engine Control Controller 4 First Throttle 5 Second Throttle 6 Input Shaft Rotation Sensor 7 Output Shaft Rotation Sensor 8 Crank Angle Sensor 9 Gear Ratio Change Means 10 Continuously Variable Transmission 12 Accelerator Pedal 13 Throttle Actuator 18c Power Roller 60 Control valve 61 Step motor 200 Shift control means 201 Gear ratio changing means 202 Engine control means 203 Engine torque reduction means 204 Engine torque calculation means 205 Inner torque calculation means 206 Target drive torque calculation means 207 Drive torque determination means

Claims (4)

[Claims] 1. A gear ratio changing means for changing a gear ratio of a continuously variable transmission, a target gear ratio is calculated according to a driving state of a vehicle, and the gear ratio changing means is controlled according to the target gear ratio. A control device for a vehicle with a continuously variable transmission, comprising: a shift control means for controlling the engine according to the driving state of the vehicle; and a continuously variable transmission when the shift control means performs an upshift. And an engine torque reducing means for suppressing the engine torque according to the driving torque of the control device for a vehicle with a continuously variable transmission. 2. A gear ratio changing means for changing a gear ratio of a continuously variable transmission, a target gear ratio is calculated according to a driving state of a vehicle, and the gear ratio changing means is controlled according to the target gear ratio. In a control device for a vehicle with a continuously variable transmission, the engine torque calculating means for calculating an engine torque, and the continuously variable transmission. An inertia torque calculation means for calculating the inertia torque, a target drive torque calculation means for calculating the target value of the drive torque by subtracting the inertia torque from the engine torque, and Drive torque determining means for determining whether or not the detected value is larger than the target value, and detection of the drive torque based on the determination result. When the value is equal to or higher than the target value, the control device for a continuously variable transmission with the vehicle, characterized in that a suppressing engine torque reduction means the engine torque. 3. The control device for a vehicle with a continuously variable transmission according to claim 2, wherein the engine torque calculation means estimates an actual engine torque. 4. The control of a vehicle with a continuously variable transmission according to claim 2, wherein the inertia torque calculation means calculates the inertia torque based on a change in a target input speed of the continuously variable transmission. apparatus.