JP3351281B2 - Transmission control device for continuously variable transmission - Google Patents

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 shift control device for a vehicle having a continuously variable transmission, and more particularly to a shift of a continuously variable transmission connected to an engine with a supercharger having a supercharging pressure reducing means. The present invention relates to a control device.

[0002]

2. Description of the Related Art Continuously variable transmissions used in vehicles include:
Conventionally, a belt type, a toroidal type, and the like are known. In these continuously variable transmission shift control devices, an automatic transmission mode in which a target gear ratio is determined according to a vehicle speed VSP and a throttle opening TVO (or an accelerator opening). In addition, in addition to the conventional manual transmission, there is known a vehicle having a manual mode capable of setting an arbitrary gear position.
There is Japanese Patent Application No. 8-4810 proposed by the present applicant.

[0003] This is a manual mode in which the speed ratio of a continuously variable transmission is set to an arbitrary gear by operating a shift lever to an upshift or downshift position. Regardless of the degree TVO, the driver can select a desired gear ratio (shift speed).

In a continuously variable transmission such as a toroidal type or a V-belt type, the gear ratio is continuously changed while receiving the reaction force of the transmission torque by the hydraulic pressure of the hydraulic servo mechanism.
When the transmission torque fluctuates, the speed change mechanism is displaced by the influence of bending or backlash of each part, and this displacement does not appear on the hydraulic servo mechanism side, so that a phenomenon called a torque shift in which the speed ratio shifts occurs.

As a device for suppressing the torque shift, Japanese Patent Application Laid-Open No. 7-4508 proposed by the present applicant is known.

In this technique, the engine torque is estimated in advance from the relationship between the throttle opening TVO or the intake air amount Qa and the engine speed Ne, and the torque shift is corrected from the estimated input torque and the target gear ratio.

[0007]

As an engine connected to a continuously variable transmission, an engine provided with a supercharger is known. In the case of an engine with a supercharger, when the throttle is rapidly closed, In order to prevent the internal pressure of the intake pipe on the upstream side of the throttle from suddenly increasing, a device equipped with a supercharging pressure reducing device such as a recirculation valve or a supercharging relief valve that temporarily connects the downstream and the upstream of the supercharger is used. is there.

However, in the conventional shift control device, the throttle opening TVO or the intake air amount Qa
In order to correct the torque shift by estimating the engine torque from the relationship between the engine speed Ne and the engine speed Ne, when the continuously variable transmission is connected to a supercharged engine equipped with a supercharging pressure reducing device, the throttle is rapidly closed. The boost pressure reduction device is activated,
When the relationship between the throttle opening TVO and the intake air amount Qa and the generated torque of the engine is broken, especially when the boost pressure reducing device is mechanically controlled in accordance with the pressure downstream of the throttle, the engine control device and the shift control are performed. It is difficult for the device to detect the operation of the supercharging pressure reducing device, and the operation of the supercharging pressure reducing device increases the difference between the actual engine torque and the engine torque estimated by the transmission control device. There is a problem that the shift correction is not accurately performed, the gear ratio is largely shifted, and a torque fluctuation occurs. In addition, in a shift control device having a manual mode in addition to the automatic shift mode, the throttle opening TVO in the manual mode is reduced. The shift is not performed only by the change, so if the throttle is suddenly closed and the boost pressure reduction device is activated, the engine torque will suddenly decrease. Engine braking Te is excessive, there is a problem of reducing the drivability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is directed to a torque fluctuation of a continuously variable transmission which is connected to an engine having a supercharging pressure reducing device and has an automatic transmission mode and a manual mode. And to improve drivability.

[0010]

According to a first aspect of the present invention, as shown in FIG. 27, an engine 30 having a supercharging means 110 is provided.
A supercharging pressure reducing means 110 for reducing a supercharging pressure in an intake passage according to an operating condition; a continuously variable transmission 10 connected to the engine 30; and a continuously variable transmission 1 according to a driving state of a vehicle.
The automatic transmission mode sets a target gear ratio of the continuously variable transmission 10 based on a signal from the automatic gearshift mode target gear ratio setting means 120 for setting a target gear ratio of 0 and a gear shift command means 121 operated by the driver. A manual mode target gear ratio setting means 122 for setting one of the gear positions;
A shift mode switching unit 123 for selectively switching between the automatic shift mode and the manual mode; and a shift control unit 124 for changing a speed ratio of the continuously variable transmission 10 based on an output of the shift mode switching unit 123. In the transmission control device for a continuously variable transmission, an operating state detecting means for detecting an operating state based on at least an operation speed of an accelerator pedal or an input shaft speed, and an overrun based on a detection result of the operating state detecting means. Supply pressure reducing means 100
And an operating characteristic changing means 102 for changing the operating characteristics of the supercharging pressure reducing means 100 based on the shift mode selected by the shift mode switching means 123.

According to a second aspect of the present invention, in the first aspect, when the shift mode switching means 123 selects the manual mode, the operating characteristic changing means 102 sets the operation speed on the release side of the accelerator pedal to a predetermined value. Is exceeded, the operation of the supercharging pressure reducing means 100 is commanded.

According to a third aspect of the present invention, in the first aspect, when the shift mode switching means 123 selects the automatic shift mode, the operating characteristic changing means 102 increases the operation speed on the release side of the accelerator pedal. In some cases, the operation of the supercharging pressure reducing means 100 is commanded even if the speed of change of the input shaft speed is slow, and if the speed of change of the input shaft speed is fast even when the operation speed on the release side of the accelerator pedal is low, The operation of the supply pressure reducing means 100 is commanded.

In a fourth aspect based on the first aspect, the shift control means 124 includes an input torque calculating means 125 for calculating an input torque based on a command value of the supercharging pressure reducing command means 101; And a compensating means 126 for compensating for a torque shift based on the result of calculating the input torque.

According to a fifth aspect of the present invention, in the first aspect, the shift control means 124 changes the shift speed when the supercharging pressure reducing command means 101 commands the operation of the supercharging pressure reducing means 101. And a shift speed correcting means 127 that increases.

[0015]

Therefore, according to the first invention, when an engine with a supercharger provided with a supercharging pressure reducing device is connected to a continuously variable transmission, the state in which the accelerator pedal is depressed is suddenly changed to the release side. Command the operation to the supercharging pressure reducing means,
At the same time as temporarily lowering the torque generated by the engine,
Speed change (upshift) can be performed quickly and smoothly while releasing the inertia of the drive system, and the control characteristics of the supercharging pressure reducing means can be changed between the automatic transmission mode and the manual mode set in the continuously variable transmission. In any of the shift modes, the engine is temporarily lowered and the inertia of the drive system is smoothly released, and the manual mode is provided by being connected to the engine having the supercharging means and the supercharging pressure reducing means. In addition, the operability and control accuracy of the continuously variable transmission can be improved.

According to a second aspect of the present invention, when the shift mode is the manual mode, the condition for operating the supercharging pressure reducing means is set only in a large region where the accelerator pedal operation speed on the release side exceeds a predetermined value. By suppressing the frequent operation of the supercharging pressure reducing means, the engine brake is prevented from becoming excessive, and the continuously variable transmission connected to the supercharging means and the engine with the supercharging pressure reducing means. This makes it possible to greatly improve the operability of the machine in the manual mode.

According to a third aspect of the present invention, when the shift mode switching means selects the automatic shift mode, the shift is performed based on operating conditions such as the amount of depression of the accelerator pedal, for example, based on a sudden release of the accelerator pedal. The shift to the Hi side is performed, but when shifting to the Hi side, it is necessary to release the inertia energy of the drive system to reduce the torque fluctuation. Therefore, the operation speed on the release side of the accelerator pedal is high. Sometimes, even if the speed of change of the input shaft speed is slow, the operation of the supercharging pressure reducing means is commanded, and if the speed of change of the input shaft speed is fast, even if the operation speed on the release side of the accelerator pedal is slow, By instructing the operation of the pressure reducing means, the engine torque is temporarily reduced, and at the same time, the inertia energy of the drive system is quickly released by shifting to the Hi side. Even if the input torque drops suddenly, the reduction in the input shaft speed of the continuously variable transmission will offset the loss of engine torque by the inertia energy, thus mitigating torque fluctuations and reliably preventing shift shock. This allows smooth shifting.

According to a fourth aspect of the invention, in the continuously variable transmission, a torque shift occurs due to a sudden decrease in the transmission torque due to a temporary decrease in the input torque due to the operation of the supercharging pressure reducing means. By calculating the input torque based on the command value of the pressure reduction command means and compensating for the torque shift, the accuracy of the torque shift compensation control can be improved, and torque fluctuations such as when the accelerator pedal is released can be ensured. Can be prevented.

According to a fifth aspect of the present invention, the shift speed is increased when the supercharging pressure reduction instructing unit instructs the operation of the supercharging pressure reducing unit. , The inertia energy of the drive system can be quickly released, and a quick shift can be realized while reducing the torque fluctuation.

[0020]

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

FIG. 1 shows a continuously variable transmission 1 which employs a double-cavity toroidal type continuously variable transmission 10 as a continuously variable transmission, a turbocharger 32 as a supercharger and a recharger as supercharging pressure reducing means. Circulation valve 33
1 shows an example in which the present invention is applied to a case where the engine 30 is connected to the engine 30. The continuously variable transmission 10 is connected to the engine 30 via a torque converter 12 having a lock-up clutch (not shown) and a forward / reverse switching device 40. In the continuously variable transmission 1, a step motor 61 responsive to a command value of a shift control controller 2 controls a gear ratio of a toroidal type continuously variable transmission 10 via a hydraulic control device 4.

The continuously variable transmission 1 which is the main component of the continuously variable transmission 1
0 is a half toroidal type first toroidal transmission unit 18
And a second toroidal transmission section 20 and a double cavity type having two sets of input / output disks.

As shown in FIG. 2, the power roller 18c sandwiched between the input disk and the output disk of the first toroidal transmission section 18 is supported by an offset rotary shaft 50b. The trunnion shaft 50a, which drives the boom 50b in the vertical direction in the figure and is rotatable around the shaft, is driven in the axial direction by a hydraulic servo cylinder 50. Although the power roller 18c of the first toroidal transmission unit 18 has been described with reference to FIG. 2, the power roller of the second toroidal transmission unit 20 has the same configuration.

In accordance with the vertical displacement of the trunnion shaft 50a, the inclination angle of the power roller 18c (the trunnion shaft 5
0a), the gear ratio is continuously changed.

On the other hand, as shown in FIGS. 1 and 3, an accelerator pedal (not shown)
A throttle valve 35 is disposed between the throttle valve 35 and the air cleaner 34.
A turbocharger 32 driven by zero exhaust gas is provided, and an intercooler 36 is interposed downstream of the turbocharger 32.

A bypass passage 31A is provided between the upstream and downstream of the turbocharger 32. The bypass passage 31A has a recirculation valve 33 driven in accordance with a pressure downstream of the throttle valve 35. Is interposed. The bypass passage 31 </ b> A communicates with the intake passage 31 between the air flow meter 8 provided downstream of the air cleaner 34 and the turbocharger 32 on the upstream side, and communicates with the intercooler 36 and the throttle valve 35 on the downstream side.

A pilot passage 38 for guiding the pressure downstream of the throttle valve 35 to the recirculation valve 33 is driven by the engine controller 3.
While the solenoid valve 37 is interposed and the operation signal RVsol from the engine control controller 3 is ON, the solenoid valve 37 opens to permit the operation of the recirculation valve 33, while the operation signal RVsol is ON. The solenoid valve 37 closes and the operation of the recirculation valve 33 is prohibited.

The recirculation valve 33 operates during a period in which the solenoid valve 37 is open.
When the downstream negative pressure is less than the predetermined value Pth, the valve is opened, and the pressure downstream of the turbocharger 32 is released upstream through the bypass passage 31A as described above, thereby preventing a sudden increase in the pressure in the intake pipe. In addition, it suppresses a decrease in turbine speed and the generation of intake noise, and prevents an error from occurring in the intake air amount Qa measured by the air flow meter 8.

The throttle valve 35 is provided with an opening sensor (not shown), which sends the throttle opening TVO to the engine controller 3. The engine controller 3 sends the throttle opening TVO and the intake air amount Qa.
And controls the fuel injection amount of the engine based on the engine speed Ne and the speed change controller 2
Valve operation signal RVsol from
, The solenoid valve 37 is driven.

The shift control controller 2 reads the throttle opening TVO (or accelerator pedal opening ACS) in response to the driver's operation of the accelerator pedal and the engine speed Ne from the engine control controller 3 and the continuously variable transmission 10. The input shaft rotation speed Nt detected by the input shaft rotation sensor 6, the output shaft rotation speed No detected by the output shaft rotation sensor 7, and a shift switch 5 A (shift command means) responsive to the operation of the shift lever 5 are set by the driver. The read shift position POS and shift mode MODE respectively are read,
The following shift control is performed.

Here, the continuously variable transmission 1 has a manual mode in addition to the automatic transmission mode. The select switch 5A of the shift lever 5 is configured as shown in FIG. A manual mode changeover switch 13 (shift mode changeover means), an up switch 8 and a down switch 9 in addition to the conventional automatic shift mode such as the D range.
Is switched from the D range to the manual mode or vice versa each time the signal passes through the central manual mode switch 13.

In the automatic transmission mode (D range), FIG.
As shown in the figure, the target input shaft speed RREV0 (or the target gear ratio) corresponding to the vehicle speed VSP is set using the throttle opening TVO or the accelerator opening ACS as a parameter. In FIG. 4, "P", "R", and "N" indicate the shift positions of parking, reverse, and neutral, respectively.

On the other hand, in the manual mode, when the up switch 8 or the down switch 9 is turned on by operating the shift lever 5, for example, the shift stage GP is switched between the first to sixth speeds based on the shift map of FIG. The target input shaft rotation speed RREV0 or the target speed ratio i (GP) is set in accordance with the gear stage GP. However, GP = 1 to 6.

In this manner, the actual target input shaft rotation speed RREV according to the operation state is obtained from one of the maps of the automatic transmission mode and the manual mode, and the stepping motor 61 (FIG. 1, FIG.
2 (see FIG. 2), a control amount ASTP corresponding to the target gear ratio RTO and the torque shift amount is commanded.

As shown in FIG. 2, the transmission ratio changing means includes a hydraulic servo cylinder 50 for axially driving a trunnion shaft 50a supporting a power roller 18c of the continuously variable transmission 10, and a step motor. The control valve 60 mainly supplies the hydraulic oil to the hydraulic servo cylinder 50 while feeding back the actual gear ratio in accordance with the drive of the trunnion shaft 50a and the displacement of the trunnion shaft 50a. The spool 63 is driven in accordance with the instruction of the hydraulic servo cylinder 50 to supply and discharge the hydraulic pressure to the oil chambers 50H and 50L above and below the piston 50P of the hydraulic servo cylinder 50.

On the other hand, the trunnion shaft 50 corresponding to the hydraulic pressure
a in the axial direction and the displacement around the axis (= power roller 18)
(tilt angle of c) is fed back to the sleeve 64 which moves relative to the spool 63 via a follower mechanism 67 including a link, and the hydraulic servo cylinder 50
Is adjusted according to the drive amount of the step motor 61 in accordance with the target speed ratio RTO and the tilt angle of the power roller 18c, that is, the actual speed ratio RTO. Is determined according to.

The shift control controller 2 is configured as shown in the control conceptual diagram of FIG. 5. In the automatic shift mode, the target input shaft speed map value is obtained from the map of FIG. 15 in accordance with the vehicle speed VSP using the throttle opening TVO as a parameter. RREV
0 in the manual mode in accordance with the gear position GP and the vehicle speed VSP from the map of FIG.
REV0, a target rotation speed calculation unit 71 for calculating each
In addition to the target rotation speed change amount determining unit 72 that calculates the actual target rotation speed RREV with a first order lag from the target input shaft rotation speed map value RREV0, the throttle opening TVO and the throttle opening TVO based on the engine torque map shown in FIG. Engine speed N
An input torque estimating unit 80 for estimating the engine torque Te from e.

Then, the recirculation valve (R
V) The operation determining unit 81 determines that the target shift speed dRREV0 (change speed of the input shaft rotation speed) and the throttle operation speed dTVO
The operating state of the recirculation valve 33 is determined from (or the operating speed of the accelerator pedal).

The engine torque Te estimated by the engine torque estimating section 80 from the throttle opening TVO and the engine speed Ne is continuously variable by the input torque estimating section 82 in accordance with the operation state of the recirculation valve (RV) 33. The input torque Tin to the transmission 10 is corrected, and the input torque Tin is subjected to first-order lag or moving average filtering by a filter 83 to obtain an estimated input torque T
It is calculated as if.

Then, the control step number determining unit 73 calculates the actual target speed ratio RRTO obtained from the actual target rotation speed RREV.
The target step number DSR of the stepping motor 61 in consideration of the torque shift from the estimated input torque Tif of the first order delay
After obtaining the STP, the step motor control section 74 changes the actual control amount (the number of steps) ASTP toward the target step number DSRSTP according to the response characteristics of the step motor 61.

Further, a recirculation valve (R
V) The operation control unit 84 controls the recirculation valve 3 set by the recirculation valve operation determination unit 81.
The solenoid valve 3 is sent to the engine controller 3 in accordance with the state of the operation flag Frv that permits the valve opening operation of the solenoid valve 3.
7, the operation signal RVsol is set to control the operation of the recirculation valve 33.

Here, an example of the control performed by the shift control controller 2 is shown in the flowcharts of FIGS.
The details will be described below with reference to the control conceptual diagram of FIG.
Each flowchart is performed at predetermined time intervals, for example, 10 msec.
It is executed each time.

First, FIG. 6 is a flowchart of a signal measurement process for detecting a driving state of a vehicle and an operation state of a driver.
In step S1, the throttle opening TVO and the engine speed Ne are read from the engine controller 3 as the operating state of the engine 30, while the input shaft speed Nt, the output shaft speed No, and the shift position POS are read from the continuously variable transmission 1. The shift mode MODE is read.

Then, in step S2, the continuously variable transmission 1
The vehicle speed VSP is obtained by multiplying the output shaft rotation number No of 0 by the conversion constant A.
And the previous value of the throttle opening TVOol
From the difference between d and the current value, the throttle operation speed dT is calculated from the following equation.
Find VO.

DTVO = TVO−TVOold (1) Accordingly, the throttle operation speed dTVO on the closing side when the accelerator pedal is released is represented by a negative value.

After obtaining the throttle operation speed dTVO, the previous value TVOold is updated with the current throttle opening TVO and the process is terminated in preparation for the next process.

Next, the flow chart of FIG. 7 shows an outline of the shift control performed based on the operating state obtained in steps S1 and S2.

Step S3 is a shift determining section for calculating a target input shaft rotation speed map value RREV0 according to the driving state of the vehicle, as shown in the flowchart of FIG.
Corresponds to the target rotation speed calculation unit 71 shown in the control conceptual diagram of FIG.

In step S4, an operation flag Frv for permitting the opening operation of the recirculation valve 33 is set based on the throttle operation speed dTVO and the shift mode MODE and a target shift speed dRREV0 described later (recirculation valve). Operation determining unit 81),
In step S5, an operation signal RVsol of the solenoid valve 37 is set based on the operation flag Frv, as shown in a flowchart of FIG. 11 described later (recirculation valve operation control unit 84).

Next, in the shift control section in step S6, the first-order lag is determined according to the shift state from the actual target input shaft rotation speed RREV obtained in step S3 and the operation state (operation signal RVsol) of the recirculation valve 33. It calculates the actual target rotation speed RREV, and corresponds to the target rotation speed change amount determination unit 72 in the control conceptual diagram shown in FIG.

Then, the CVT control unit in step S7
As shown in the flowcharts of FIGS. 13 and 14, the control input STP of the step motor 61 according to the actual target rotational speed RREV and the estimated input torque Tin obtained by filtering the estimated input torque Tin obtained according to the operation state of the engine 30 are filtered. T
The target step number DSRSTP of the step motor 61 is obtained from the torque shift compensation control amount TS1 based on if.
Actual control amount A according to response characteristics of step motor 61
STP is calculated, and corresponds to the control step determining unit 73, the step motor control unit 74, and the input torque estimating unit 80 to the filter 83 in the control conceptual diagram shown in FIG.

Next, in the signal output section of FIG.
8, the control amount A obtained in step S7 of FIG.
In addition to commanding STP to the step motor 61, an operation signal RVsol for controlling the operation of the recirculation valve 33 is set and output to the engine controller 3.

Each part of the shift control having the above-described outline will be described in detail below.

First, the shift determining section in step S3 shown in the flowchart of FIG. 7 is composed of a subroutine shown in FIG. 9. In step S10, the current shift mode is determined.

If the shift mode read in step S1 is the manual mode, the process proceeds to step S13. If the shift mode is the automatic shift mode, the process proceeds to step S11. From the map shown in FIG. 15, the throttle opening TVO and the vehicle speed VSP are used. After obtaining the target input shaft rotation speed map value RREV0, in step S12, the time constant Ka in the automatic transmission mode is set to the first-order lag time constant Kr. It should be noted that the time constant Ka in the automatic shift mode is changed according to the running state.

On the other hand, in the manual mode after step S13, when the signal of the up switch 8 or the down switch 9 corresponding to the position of the shift lever 5 operated by the driver changes from OFF to ON, the map shown in FIG. As described above, a command is issued for shifting to an adjacent gear stage GP.

That is, in step S13, when the signal from the up switch 8 changes from OFF to ON, the routine proceeds to step S14, where the gear is upshifted to the one-stage Hi side. The time constant Ku1 at the time of the mode upshift is substituted for the first-order lag time constant Kr.

On the other hand, if the signal from the down switch 9 changes from OFF to ON in step S15, the routine proceeds to step S16, in which the gear is downshifted by one gear to the low side, so that GP = GP-1. At the same time, the time constant Kd1 at the time of the downshift in the manual mode is substituted for the first-order time constant Kr.

Time constants Ku1, K in the manual mode
d1 is set so that Ku1 ≧ Kd1, and the response at the time of downshift is set faster than at the time of upshift. This is because the driver may request engine braking during downshifting, and during such braking, quick downshifting is given priority over shift shock.

When the driver does not operate the shift lever 5, the current gear stage Gp is maintained.

Thus, in step S17, the gear position GP set in steps S13 to S16 is set.
From the vehicle speed VSP obtained in step S2, FIG.
Target input shaft speed map value RR based on the shift map
Calculate EV0.

Next, in step S18, the target shift speed dRREV0 is obtained from the difference between the target input shaft speed map value RREV0 obtained according to the shift mode and the previous value RREV0old.
Ask for.

DRREV0 = RREV0−RREV0old (2) Then, in step S19, after updating the previous value RREV0old with the current target shift speed dRREV0 in preparation for the next process, the process is terminated and the main routine of FIG. Return to routine.

Next, the recirculation valve operation judging section shown in step S4 in FIG. 7 is constituted by a subroutine in FIG.
The recirculation valve 3 is determined based on the throttle operation speed dTVO determined in step S18, the target shift speed dRREV0 similarly determined in step S18, and the shift mode MODE.
The operation flag Frv that permits the valve opening operation of No. 3 is set based on the map of FIG. 20 or FIG.

First, in the case of the automatic transmission mode, FIG.
The operation flag Frv is set in accordance with the speed of the throttle 35 on the closing side (dTVO <0) and the decrease of the target shift speed dRREV0 based on the map of FIG. In the region where the speed dTVO is equal to or higher than the relatively slow predetermined value dTVO2, the operation flag Frv is set to 0 irrespective of the target shift speed dRREV0 and the opening of the recirculation valve 33 is prohibited, while the operating speed on the closing side is set. In a region where dTVO is large and less than the predetermined value dTVO2, the operation flag Frv is set to 1 in accordance with the target shift speed dRREV0 and the closing throttle operation speed dTVO at the boundary of the graph in the figure, and the recirculation valve The opening of the valve 33 is permitted.

That is, when the operation speed dTVO on the closing side is slightly higher and is less than or close to the predetermined value dTVO2, the target shift speed dRREV0 is -max (the maximum value of the Hi-side shift speed).
The operation flag Frv is not set to 1 until it becomes close, but when the closing-side operation speed dTVO increases to -max (the maximum value of the closing-side speed), the target shift speed dRREV0.
Is smaller than the predetermined value dRREV
If 0a or more, the operation flag Frv is set to 1 and the opening of the recirculation valve 33 is permitted.

In the automatic shift mode, as shown in FIG. 15, the shift is performed according to the throttle opening TVO. Therefore, when the throttle valve 35 is suddenly closed when the accelerator pedal that has been depressed is released, the target shift speed is set. dRRE
Since both V0 and dTVO are near -max and a quick shift to the HI side is required, the recirculation valve 33 is opened in such a region to temporarily reduce the input torque from the engine 30. If it is reduced, the inertia torque of the drive system is released smoothly as described later,
Enables smooth shifting.

On the other hand, in the manual mode, the target input shaft speed map value RREV0 is set according to the vehicle speed VSP as shown in the map of FIG.
A change in gear alone does not cause a large shift. For this reason, as in the automatic transmission mode, the dTVO2 having a relatively slow closing speed is used.
When the operation of the recirculation valve 33 is permitted from the vicinity, when the recirculation valve 33 is opened, the input torque from the engine 30 is temporarily reduced, and the engine brake may become excessive.

For this reason, in the manual mode, FIG.
As shown in the figure, regardless of the target shift speed dRREV0,
The closing speed of the throttle 35 is a predetermined value dT near -max.
The operation flag Frv is set to 1 and the operation of the recirculation valve 33 is permitted only in a region less than VO1, that is, in a region where the closing speed is high, while the operation flag Frv is set to 0 and the recirculation is set in other regions. The operation of the ration valve 33 is prohibited.

When the setting of the operation flag Frv is completed in step S20, the process returns to the main routine of FIG. 7 again, and the processing of the recirculation valve control unit in step S5 is performed.

The recirculation valve control section comprises a subroutine shown in FIG. 11. First, in step S21, it is determined whether or not the operation flag Frv has changed from 0 to 1, and the operation flag Frv is changed from 0 to 0. Only when it has changed to 1, the process proceeds to step S25, and the timer Timr1
Is set to the predetermined value Tk, and the process ends.

On the other hand, if the determination in step S21 is NO, the process proceeds to step S22, where the timer Timr1 is set to 0.
Is determined, and if it is 0, the process proceeds to step S26, and the operation signal RVsol of the solenoid valve 37 is set to 0.
(= OFF) to end the processing, otherwise, to step S23, the timer Timr1
Is subtracted by a predetermined value, and in step S24, the operation signal RVsol is set to (= ON), the recirculation valve 33 is allowed to open, the processing is terminated, and the process returns to the main routine of FIG. The process proceeds to the shift control unit in step S6.

Therefore, the operation flag Frv is changed from 0 to 1
Since the solenoid valve 37 is opened during a period Tk from the point when the timer Timr1 becomes 0 to the time when the timer Timr1 becomes 0, as shown in FIG. And open the valve (O in the figure)
N).

The shift control unit in step S6 is constituted by a subroutine shown in FIG. 12. First, in step S30, the actual target input shaft rotation speed RREV during the previous control is set to the previous value RRE.
After storing in Vold, in step S31, it is determined whether or not the shift is currently in a transitional state (during shifting). If it is in a steady state, the process proceeds to step S33, where the target input shaft speed R
REV0 is set as the actual target input shaft rotation speed RREV, the process is terminated, and the process returns to the main routine of FIG. 7, while if the process is in a transient state, the process proceeds to the processes after step S32.

In step S32, the operation signal RVsol
Is determined to be 1, that is, whether or not the opening of the recirculation valve 33 is permitted. If the opening is permitted, the process proceeds to step S34, and the predetermined value is calculated from the first-order time constant Kr. After setting the time constant of the first-order lag to be small by subtracting K1, the process proceeds to step S35, while if prohibited (operation signal RVsol = 0), the process directly proceeds to step S35 to proceed to step S12, step S14 or S15. Time constant Kr = Ka, K set by
Actual target input shaft speed RREV according to u1 or Kd1
Is calculated.

In step S35, the actual target input shaft rotation speed RREV is changed from the previous value RREVold to the map value RREV0.
Using the first-order lag time constant Kr set as described above according to the shift conditions and the like, the actual target input shaft rotation speed RREV with the first-order lag is calculated by the following equation.

RREV = (RREV0 + RREVold × Kr) / (Kr + 1) (3) Therefore, by the processing of step S35, the primary target actual target input shaft rotation speed RREV can be changed as shown in FIG. The rotation speed is set to gradually change toward the rotation speed map value RREV0, and when the operation of the recirculation valve 33 is permitted in the case where the operation signal RVsol = 1, the time constant is decreased to increase the shift speed and thereby achieve a quick shift. Is what you do.

In this way, when the actual target input shaft rotational speed RREV of the first-order lag is obtained based on the time constant Kr and the shift determining section is finished, the process returns to the main routine of FIG.
Of the CVT control process of FIG.

The CVT control process in step S7 is performed as shown in FIG.
3. First, in step S40, a subroutine shown in FIG. 14 is used to calculate the ratio between the temporarily delayed actual target input shaft speed RREV obtained from the above equation (3) and the output shaft speed No of the continuously variable transmission 10. The actual target gear ratio RRTO is obtained.

Next, in step S41, the control step number STP, which is the drive amount of the step motor 61, is calculated from the map shown in FIG. 18 based on the actual target gear ratio RRTO obtained in step S40.

In step S42, it is determined whether or not the operation flag Frv for permitting the opening operation of the recirculation valve 33 is 1, that is, whether or not the opening of the recirculation valve 33 is permitted. If the flag Frv = 1, the process proceeds to step S44, where the estimated input torque Tin to the continuously variable transmission 10 is set to Tin = 0, while if the operation flag Frv = 0, the process proceeds to step S43.
Proceed to.

In step S44, the operation flag Frv is set to 1 and the recirculation valve 33 is opened, so that the input torque Tin from the engine 30 is
As shown in FIG. 26, the input torque Tin is set to 0 because it may temporarily decrease and become a negative value.

On the other hand, in step S43 when the operation flag Frv = 0, the opening of the recirculation valve 33 is prohibited, and the torque from the engine 30 is input to the continuously variable transmission 10. The engine torque Te is calculated as the estimated input torque Tin based on the map shown in FIG. 17 from the engine speed Ne and the throttle opening TVO read in step (1). The map in FIG. 17 is a map in which the engine torque Te according to the engine speed Ne is set in advance using the throttle opening TVO as a parameter. Here, it is assumed that torque converter 12 is used as a starting element and is always in a lockup state during traveling.

After obtaining the estimated input torque Tin in accordance with the operation state of the recirculation valve 33 based on the operation flag Frv in steps S43 and S44, a predetermined filter process is performed on the estimated input torque Tin in step S45. For example, a filter process such as a first-order lag or a moving average value is added, and the estimated input torque after the filter process is set to Tif.

In step S46, the torque shift compensation amount (step number) TS1 of the continuously variable transmission 10 is calculated based on the map shown in FIG. 19 based on the estimated input torque Tif and the actual target gear ratio RRTO obtained in step S40. Is calculated. The map shown in FIG.
1, which is set in advance according to the characteristics of the gear ratio changing means and the like, and using the estimated input torque Tif as a parameter,
Torque shift compensation amount TS according to actual target gear ratio RRTO
1 is set. Here, the estimated input torque Tif for compensating for the torque shift is determined in step S4.
5, a filter processing such as a first-order lag is added, so that an excessive change in the control amount of the step motor 61 due to a sudden change in the throttle opening TVO is prevented.

Next, in step S50 of FIG. 14, the target step number DSRSTP is calculated from the sum of the control step number STP obtained in step S41 and the torque shift compensation amount TS1 obtained in step S46.

In steps S51 to S56, a control amount ASTP is calculated from the target step number DSRSTP and the current control amount (step number) ASTP according to the response speed of the step motor 61, and the target step number D is calculated.
When SRSTP is larger than the current control amount ASTP, the control amount ASTP is increased or decreased by a preset control amount DSTP to the target value DSRSTP. DSTP indicates the number of steps per unit time, and the step motor 61
Are set in advance in accordance with the speed characteristics of.

That is, as shown in FIG. 24, since the step motor 61 cannot instantaneously achieve the target position, when the control amount ASTP actually output to the step motor 61 is larger than the target step number DSRSTP, the predetermined control amount The control valve 60 is increased by DSTP.
The step motor 61 is driven so that the spool 63 has a predetermined gear ratio.

The control amount ASTP obtained from the flowcharts of FIGS. 6 to 14 is output from the transmission control controller 2 to the step motor 61 in step S8 of the signal output unit in FIG. 8, and the axial displacement of the trunnion shaft 50a is changed. , The power roller 18c is tilted at a speed corresponding to the first-order lag constant Kr, and the continuously variable transmission 10 is shifted to the actual target speed ratio RR.
It is set to TO.

Then, based on the operation signal RVsol also transmitted in step S8, the engine control controller 3 drives the solenoid valve 37 that permits the operation of the recirculation valve 33, and the torque when the accelerator pedal is released. It alleviates fluctuations.

Next, the operation of the supercharging pressure reducing means including the recirculation valve 33 in the engine 30 having the turbocharger 32 will be described.

As shown in FIG. 25, the throttle opening TV
When O is rapidly closed from a high opening to a low opening, the throttle operation speed dTVO on the closing side increases, and FIG.
In step S20 in FIG. 10, the operation flag Fr in the manual mode is set to approach -max shown in FIG.
v is set to 1, and in the automatic shift mode, the operation flag Frv is set to 1 according to the target shift speed dRREV0.

When the rapid closing of the throttle valve 35 is detected in step S20, as shown in FIGS. 10 and 22, the period in which the timer Timr1 exceeds the predetermined value Tk from the time when the operation flag Frv becomes 1 is set. When the operation signal RVsol is turned on and the solenoid valve 37 is opened, and the pressure Pt downstream of the throttle valve 35 falls below a predetermined threshold value Pth shown in FIG. 25, the recirculation valve 33 opens. Intercooler 3
The pressurized air that has passed through 6 is circulated upstream of the turbocharger 32 via the bypass passage 31A.

Therefore, when the throttle valve 35 is rapidly closed with the opening degree of the throttle valve 35 reduced from the high opening degree, the supercharging pressure can be released to the upstream of the turbocharger 32, and the turbine speed of the turbocharger 32 is prevented from lowering. At the same time, the intake air amount Qa due to the backflow to the air flow meter 8
Erroneous detection and generation of intake noise can be prevented.

At the same time, the recirculation valve 33
, The supercharging pressure to the engine 30 is reduced, so that the engine torque Te is temporarily suddenly reduced according to the valve opening period Tv of the recirculation valve 33, and the input torque is lost (Te ≦). 0).

Here, when the continuously variable transmission 1 is set to the automatic transmission mode, the shift to the Hi side is performed based on the rapid closing of the throttle opening TVO from the map of FIG. When shifting to the Hi side, it is necessary to release the inertia energy of the drive system to reduce the torque fluctuation.

That is, in the automatic shifting mode, based on the throttle operation speed dTVO and the target shifting speed dRREV0, during the shifting on the Hi side where the inertia energy of the drive system needs to be released, the operation flag Frv is set to 1 from the map of FIG. , The solenoid valve 37 is opened, the operation of the recirculation valve 33 is permitted,
Throttle valve 3
5 Recirculation valve 33 by negative pressure downstream
, The engine torque Te can be temporarily reduced, and at the same time, the inertia energy of the drive system due to the shift to the Hi side can be rapidly released.
As shown in FIG. 25, even if the input torque Tin decreases temporarily, the loss of the engine torque is offset by the inertia energy due to the decrease in the input shaft rotation speed Nt of the continuously variable transmission 10. 10 output shaft torque T
o can be smoothly reduced as shown in the figure, and the torque fluctuation is alleviated to surely prevent the shift shock. During the operation of the recirculation valve 33, the time constant Kr of the first-order lag is reduced. Since the speed is reduced by the predetermined value K1, as shown in FIG. 23, a quick shift can be performed, and the operability of the continuously variable transmission connected to the supercharged engine 30 can be improved.

Further, due to the temporary decrease of the input torque Tin due to the operation of the recirculation valve 33, the power roller 18c is provided in the toroidal type continuously variable transmission 10.
The transmission control controller 2 determines that the throttle operation speed dTVO and the target shift speed dR in the automatic shift mode.
Since the recirculation valve 33 is controlled in accordance with REV0, the actual engine torque Te reduced by the operation of the supercharging pressure reducing device as in the conventional example and the engine torque estimated by the shift control controller 2 (estimated input torque) Tin or Tif) can be prevented from increasing, and the accuracy of the torque shift compensation control can be improved, so that the torque fluctuation at the time of rapid closing of the throttle can be reliably prevented.

On the other hand, when the continuously variable transmission 1 is set to the manual mode, the shift is performed based on the map shown in FIG.
No large shift occurs due to the sudden closing of the throttle opening TVO.

For this reason, when the throttle is suddenly closed as if the foot was released from the state where the accelerator pedal was depressed, FIG.
If the throttle operation speed dTVO is less than dTVO2 and the operation of the recirculation valve 33 is permitted, as shown by the solid line in FIG. To is transmitted to To, and the engine brake may temporarily increase.

Therefore, when the shift mode MODE is the manual mode, the condition for operating the recirculation valve 33 is set only in a large region where the throttle operation speed dTVO on the closing side is less than dTVO1, as shown in FIG. Then, by suppressing the opening of the recirculation valve 33, the engine brake is prevented from becoming excessive, and at the normal throttle valve 35 closing speed, as shown by the broken line in FIG. Step transmission 10
Output torque To of the engine 30
Operability in the manual mode of the continuously variable transmission 10 connected to the vehicle can be greatly improved.

In the above embodiment, the case where the recirculation valve 33 is used as the supercharging pressure reducing means has been described. Although not shown, the supercharging relief valve provided in the bypass passage 31A and the engine 30 It can be composed of a valve that operates according to the load,
Further, the control of the recirculation valve 33 is performed by driving a solenoid valve 37 for selectively supplying a negative pressure of the throttle valve 35, but not shown,
The recirculation valve 33 may be directly driven by an actuator or the like.

In the above embodiment, an example in which the continuously variable transmission 10 is of a toroidal type is shown. However, the same operation and effect as described above can be obtained when the continuously variable transmission 10 is of a V-belt type continuously variable transmission. be able to.

[Brief description of the drawings]

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

FIG. 2 is a conceptual diagram of gear ratio changing means of the toroidal type continuously variable transmission.

FIG. 3 is a schematic diagram showing an intake system of the engine.

FIG. 4 is a schematic view showing a shift switch.

FIG. 5 is a control conceptual diagram showing an outline of a shift control.

FIG. 6 is a flowchart illustrating an example of control performed by a shift control controller, illustrating a signal measuring unit.

FIG. 7 is a flowchart showing an example of control, and shows an outline of shift control.

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

FIG. 9 is a flowchart showing a subroutine of a shift determining unit.

FIG. 10 is a flowchart showing a subroutine of a recirculation valve operation determining unit.

FIG. 11 is a flowchart showing a subroutine of a recirculation valve operation control unit.

FIG. 12 is a flowchart showing a subroutine of the transmission control unit.

FIG. 13 is a flowchart showing the first half of a subroutine of the CVT control unit.

FIG. 14 is a flowchart showing the second half of the subroutine of the CVT control unit.

FIG. 15 is a shift map in an automatic shift mode showing a relationship between a target input shaft rotation speed map value RREV0 and a vehicle speed VSP using a throttle opening TVO as a parameter.

FIG. 16 is a shift map in a manual mode showing a relationship between a target input shaft rotation speed map value RREV0 and a vehicle speed VSP using a shift speed GP as a parameter.

FIG. 17 is a map showing the relationship between the engine speed Ne and the engine torque Te using the throttle opening TVO as a parameter.

FIG. 18 is a map showing a relationship between an actual target gear ratio RRTO and a control amount (step number) STP of a step motor.

FIG. 19 is a map showing the relationship between the actual target gear ratio RRTO and the number TS1 of torque shift compensation steps of the step motor using the estimated input torque Tin as a parameter.

FIG. 20 is a map of an operation flag Frv according to a throttle operation speed dTVO and a target shift speed dRREV0 in the automatic shift mode.

FIG. 21 is a map of an operation flag Frv according to a throttle operation speed dTVO in a manual mode.

FIG. 22 is a graph showing the relationship between time and the states of an operation flag Frv, a timer Timr1, and a recirculation valve.

FIG. 23 is a graph showing a relationship between an actual target input shaft rotation speed RREV, a target input shaft rotation speed map value RREV0, and time.

FIG. 24 is a graph showing a relationship between a target step number DSRSTP and an actual output step number ASTP.

FIG. 25 shows the operation of the recirculation valve in accordance with the throttle operation speed in the automatic transmission mode. The throttle opening TVO, the throttle downstream negative pressure Pt,
Input shaft rotation speed Nt, input torque Tin and output torque T
The relationship between o and time is shown.

FIG. 26 shows how the recirculation valve operates according to the throttle operation speed in the manual mode, and shows the relationship between the throttle opening TVO, the input torque Tin, the output torque To, and time.

FIG. 27 is a diagram corresponding to claims corresponding to the first to third inventions.

[Explanation of symbols]

 Reference Signs List 1 continuously variable transmission 2 shift control controller 3 engine control controller 5 shift lever 5A shift switch 6 input shaft rotation sensor 7 output shaft rotation sensor 8 air flow meter 10 continuously variable transmission 18c power roller 30 engine 31 intake passage 31A bypass passage 32 turbo Charger 33 Recirculation valve 34 Air cleaner 35 Throttle 36 Intercooler 37 Solenoid valve 60 Control valve 61 Step motor 71 Target rotation speed calculation unit 72 Target rotation speed change amount determination unit 73 Control step determination unit 74 Step motor control unit 80 Input torque estimation Unit 81 recirculation valve operation determining unit 82 input torque estimating unit 83 filter 84 recirculation valve operation control unit 100 supercharging pressure reducing means 01 supercharging pressure reducing command means 102 operating characteristic changing means 110 supercharging means 120 automatic gear shift mode target gear ratio setting means 121 gear shift command means 122 manual mode target gear ratio setting means 123 gear mode switching means 124 gear shift control means 125 input torque calculation Means 126 Compensation means 127 Shift speed correction means 130 Operating state detection means

────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI F02D 23/00 F02D 41/02 301D 41/02 301 F02B 37/00 303H (56) References JP-A-3-61615 (JP, A) JP-A-3-81527 (JP, A) JP-A-8-1444811 (JP, A) JP-A-9-196165 (JP, A) JP-A-7-4508 (JP, A) JP-A-7 -280052 (JP, A) JP-A-63-155138 (JP, A) JP-A-9-315186 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02D 29/00 F02D 41/00-45/00 F02B 37/00

Claims (5)

(57) [Claims] An engine provided with a supercharging means; a supercharging pressure reducing means for reducing a supercharging pressure in an intake passage according to an operating condition; a continuously variable transmission connected to the engine; An automatic transmission mode target gear ratio setting means for setting a target gear ratio of the continuously variable transmission according to a state; and a target gear ratio of the continuously variable transmission based on a signal from a gear shift command means operated by a driver. A manual mode target gear ratio setting means for setting one of a plurality of gear positions set in advance, a gear mode switching means for selectively switching between the automatic gear mode and the manual mode, and an output of the gear mode switching means. Transmission control means for changing the transmission ratio of the continuously variable transmission based on the speed change of the continuously variable transmission, based on at least the operation speed of the accelerator pedal or the input shaft rotation speed. Operating state detecting means for detecting the operating state of the vehicle, and supercharging pressure reducing instruction means for instructing operation of the supercharging pressure reducing means based on the detection result of the operating state detecting means. A shift control device for a continuously variable transmission, comprising: an operating characteristic changing unit that changes an operating characteristic of the supercharging pressure reducing unit based on a shift mode. 2. The operating characteristic changing means instructs, when the shift mode switching means selects the manual mode, an operation of the supercharging pressure reducing means when the operation speed on the release side of the accelerator pedal exceeds a predetermined value. The shift control device for a continuously variable transmission according to claim 1, wherein: 3. The system according to claim 2, wherein the operation characteristic changing means is configured to reduce the supercharging pressure when the shift mode switching means selects the automatic shift mode, when the operation speed on the release side of the accelerator pedal is fast, even if the speed of change of the input shaft speed is slow. The operation of the supercharging pressure reducing means is commanded when the change speed of the input shaft rotation speed is high even when the operation speed on the release side of the accelerator pedal is low, in addition to commanding the operation of the means. The shift control device for a continuously variable transmission according to claim 1. 4. The transmission control means includes: input torque calculation means for calculating an input torque based on a command value of a supercharging pressure reduction command means; and compensation means for compensating a torque shift based on a calculation result of the input torque. The shift control device for a continuously variable transmission according to claim 1, further comprising: 5. The shift control means includes a shift speed correcting means for increasing a shift speed when the supercharging pressure reducing command means commands the operation of the supercharging pressure reducing means. Item 3. The shift control device for a continuously variable transmission according to Item 1.