JP2005299722A - Speed change controller for continuously variable transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a speed change controller for a continuously variable transmission capable of favorably realizing acceleration response of a vehicle without causing shock of acceleration and deceleration in quick speed change control of the continuously variable transmission having high response property. <P>SOLUTION: When actual input number of rotation (solid line) exceeds target input number of rotation Npri<SB>*</SB>a (broken line), occurrence of overshooting is detected to perform transient control. In the transient control, temporary target input number of rotation Npri<SB>*</SB>k (thick line) is calculated, and actual input number of rotation (solid line) follows the temporary target input number of rotation (thick line). First, during fixed time Th, the temporary target input number of rotation Npri<SB>*</SB>k (thick line) is maintained at a target input number of rotation initial value Nprij_p. After the fixed time Th elapses, the temporary target input number of rotation Npri<SB>*</SB>k (thick line) is calculated so that the temporary target input number of rotation Npri<SB>*</SB>k (thick line) is gradually changed toward the target input number of rotation Npri<SB>*</SB>a (broken line). Consequently, actual input number of rotation (thick line) is maintained at the target input number of rotation initial value Nprij_p for the fixed time Th, and actual input number of rotation (thick line) is converged toward the target input number of rotation Npri<SB>*</SB>a after maintenance. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to the control of the input rotational speed of a continuously variable transmission capable of continuously changing the gear ratio, such as a V-belt system or a toroidal system, and in particular, the actual input rotational speed exceeds the target input rotational speed. It relates to control when a chute occurs.

A continuously variable transmission that can be continuously switched without intermittently switching by setting the gear ratio, which is the ratio between the input rotational speed and the output rotational speed, to several stages has been put into practical use as a transmission mechanism in vehicles. Several years have passed. This continuously variable transmission does not cause acceleration / deceleration shocks when changing the gear ratio, and the riding performance and fuel efficiency are improved. In order to improve the acceleration response, development is progressing to meet the demand for high response that promptly follows the input speed of the continuously variable transmission to the accelerator operation.
When shifting control of a continuously variable transmission to meet the demand for high response, the actual input rotation speed of the continuously variable transmission is the target of the continuously variable transmission in normal shift control where the driver's accelerator operation is slow. Follows the input speed quickly. This normal shift control will be described below.

When the driver depresses the accelerator pedal in the hope of accelerating, for example, during an engine brake operation in which the accelerator operation amount is 0 or a minute amount and the engine throttle opening Tvo is 0/8 or a minute opening or is constant When the throttle opening Tvo of the engine is set to a state of 4/8 by the driver's accelerator opening operation from the state of the high speed driving, the vehicle driving state will behave as shown in FIGS. Indicates. FIG. 7 is a shift pattern diagram showing the target input rotational speed of the continuously variable transmission, the vehicle speed Vsp, and the increasing change in the actual input rotational speed of the continuously variable transmission (hereinafter referred to as the actual input rotational speed). FIG. 8A shows a time chart of the throttle opening of the engine. In FIG. 8B, the broken line indicates the time change of the target input speed, and the solid line indicates the time change of the actual input speed. It is a time chart which shows.
In FIG. 8, when the target input speed indicated by the broken line deviates from the actual input speed indicated by the solid line due to a change in the throttle opening, the actual input speed (solid line) follows the high response to the target input speed (dashed line). Shift control is executed so that

However, in the above-described shift control that follows a high response, in the sudden shift control in which the change in the throttle opening is abrupt, the actual input rotational speed of the continuously variable transmission is the target input rotational speed of the continuously variable transmission. Then, an overshoot occurs that exceeds the target input rotational speed. This overshoot will be described below.
Similar to the above, the engine throttle opening Tvo is 4/8 by the driver's accelerator opening operation while the engine brake is operating or the vehicle is running at a constant speed with the throttle opening Tvo being 0/8 or a minute opening. The case where the state is set will be described. The driving state of the vehicle behaves as shown in FIGS. FIG. 9 is a shift pattern diagram showing the target input rotational speed of the continuously variable transmission, the vehicle speed Vsp, and the increasing change in the actual input rotational speed. FIG. 10 (a) shows a time chart of the throttle opening of the engine. In FIG. 10 (b), the broken line indicates the time change of the target input speed, and the solid line indicates the time change of the actual input speed. It is a time chart which shows.
Referring to FIG. 10B, since the actual input rotational speed (solid line) has a high response, the actual input rotational speed (broken line) temporarily increases more rapidly than the normal shift control indicated by the one-dot chain line. After an overshoot that exceeds the maximum, the target input speed will drop suddenly.
For this reason, there is a problem that the drivability is impaired, for example, the shift controllability is deteriorated or a shock of acceleration / deceleration unexpected by the driver is caused.

Conventionally, for example, the inventions described in Patent Document 1 and Patent Document 2 have been known as inventions aimed at improving the overshoot problem.
Japanese Patent Laid-Open No. 2001-330130 FIG. JP, 2003-314675, A The control device of the continuously variable transmission of patent documents 1 is characterized by setting up three steps by feedback control until the target input rotation speed reaches the final target input rotation speed. First, the first target input speed is set, the actual input speed is rapidly increased by step shifting so as to approach the first target input speed, and then gradually increased to the second target input speed. The actual input rotational speed is gradually increased by shifting speed fixing control (feedback control) so as to approach the target input rotational speed, and thirdly, the actual input rotational speed is gradually increased by normal transmission control so as to approach the final target input rotational speed. It is intended to increase.

  The control device for a continuously variable transmission described in Patent Document 2 first changes the gear ratio quickly based on the first change speed when the accelerator pedal is greatly depressed and the gear ratio is switched to the downshift side. In addition, the gear ratio is changed slowly based on the second change speed.

  However, the conventional transmission control device for a continuously variable transmission has the following problems. In other words, since the control gain and the shift speed are set to be small in the second stage so that neither of the two inventions causes an overshoot, the acceleration response of the vehicle is sacrificed during the sudden shift control, which is desired by the driver. Accelerated running cannot be achieved.

  The present invention does not deteriorate the shift controllability even when the shift speed is increased, prevents an unexpected acceleration / deceleration shock of the driver due to the overshoot, and prevents the acceleration response of the vehicle. The present invention proposes a transmission control device for a continuously variable transmission that can be suitably realized.

For this purpose, the transmission control device for a continuously variable transmission according to the present invention is as described in claim 1.
Assuming that the continuously variable transmission is controlled so that the actual input rotational speed input to the continuously variable transmission from the engine side follows the target input rotational speed determined according to the driving state of the vehicle,
Overshoot detection means for detecting that the actual input rotational speed exceeds the target input rotational speed during the transition period during the shift control;
At the time of overshoot detection by the means, a temporary target input speed for obtaining a temporary target input speed that gradually changes from the target input speed initial value exceeding the target input speed in the overshoot direction toward the target input speed A number calculating means,
When the overshoot is detected, the shift control is performed using the temporary target input rotation speed instead of the target input rotation speed.

  According to the speed change control device of the present invention, when an overshoot of the actual input rotational speed occurs, the temporary target input rotational speed is determined, and the temporary target input rotational speed is gradually adjusted to coincide with the target input rotational speed. Because the transient control changes to, acceleration / deceleration shocks such as the actual input speed suddenly returning to the target input speed after an overshoot cannot occur, and the driver and occupant overshoot You will never notice the occurrence. In addition, the acceleration response of the vehicle can be suitably realized.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
FIG. 1 shows a power train of a vehicle provided with a shift control device according to an embodiment of the present invention, and its control system. The power train is composed of an engine 1 and a continuously variable transmission 2.
Although the engine 1 is a gasoline engine, the throttle valve is not mechanically connected to an accelerator pedal (not shown) operated by the driver, and is separated from these to accelerate the throttle valve opening by a throttle valve actuator. Electronic control is made upon request.

The continuously variable transmission 2 has an input rotational speed that is the rotational speed of the input shaft of the continuously variable transmission that is drivingly coupled to the engine side, and an output that is the rotational speed of the output shaft of the continuously variable transmission that is drivingly coupled to the drive wheel side. The gear ratio defined as the ratio with the rotational speed can be changed continuously (continuously). For example, a well-known belt-type continuously variable transmission, toroidal-type continuously variable transmission, etc. Any ratio can be used as long as the ratio can be changed steplessly (continuously). In the present embodiment, a description will be given assuming that it is a known V-belt continuously variable transmission, and a primary pulley 4 that is drive-coupled to the output shaft of the engine 1 via a torque converter 3 and a secondary pulley that is aligned with the primary pulley 4. 5 and a V-belt 6 spanned between these pulleys.
Then, a differential gear device 8 is drivably coupled to the secondary pulley 5 via a final drive gear set 7, and a wheel (not shown) is rotationally driven by these.

  The speed change operation of the continuously variable transmission 2 is such that, among the flanges forming the V-grooves of the primary pulley 4 and the secondary pulley 5, one movable flange is brought relatively close to the other fixed flange to make the V-groove width. The stroke position of both movable flanges is determined by the primary pulley pressure Ppri and the secondary pulley pressure Psec from the shift control hydraulic circuit 9, and the shift control is performed. The hydraulic circuit 9 determines the primary pulley pressure Ppri and the secondary pulley pressure Psec so as to achieve a target gear ratio i * described later.

The target speed ratio i * is obtained by calculation with reference to a speed ratio map stored in advance by the control unit 10 in order to make the actual input speed of the continuously variable transmission 2 follow a target input speed described later.
Therefore, the control unit 10 detects a signal from the throttle opening sensor 11 that detects the throttle opening Tvo of the engine 1, a signal from the vehicle speed sensor 12 that detects the vehicle speed Vsp from the number of rotations of the wheels, and the continuously variable transmission 2. A signal from the input rotation speed sensor 13 for detecting the actual input rotation speed Nprij is input.

  When the continuously variable transmission 2 executes the target speed ratio i *, the actual input rotational speed of the continuously variable transmission 2 matches the target input rotational speed calculated from the previously stored speed ratio map.

Next, a description will be given of the shift control during acceleration traveling performed by the shift control device for a continuously variable transmission according to the present invention.
When the driver desires acceleration traveling and depresses the accelerator pedal, the throttle valve of the engine 1 is opened. The control unit 10 refers to the speed ratio map stored in advance from the input throttle opening Tvo, the vehicle speed Vsp, and the actual input speed Nprij of the continuously variable transmission 2, and the target input speed Npri _* a is set, and the gear ratio i is controlled so that the actual input speed Nprij matches the target input speed Npri _* a. That is, in order to make the actual input rotation speed Nprij follow the target input rotation speed Npri _* a, a shift that continuously downshifts the target speed ratio i *, which is the ratio of the increasing actual input rotation speed to the increasing vehicle speed Vsp. Execute control. The gear ratio i is represented by the slope of a straight line connecting the point plotted by the combination of the actual input speed Nprij (vertical axis) and the vehicle speed Vsp (horizontal axis) and the origin in FIGS. The steeper slope has a larger reduction ratio (Low).

  As shown in FIGS. 7 and 8, the normal shift control executed by the control unit 10 at the time of gentle acceleration is performed according to the shift control described above, in which the actual input rotational speed (vertical axis) is the vehicle speed Vsp (horizontal axis) and the time. It increases substantially constant in relation to t (horizontal axis), and does not increase any more when it matches the target input rotational speed.

  However, when the driver suddenly depresses the accelerator pedal, the control unit 10 performs shift control for rapid acceleration. At this time, when the overshoot described above based on FIGS. 9 and 10 occurs, the control unit 10 executes the transient control described below to prevent the actual input rotational speed from suddenly dropping after the overshoot occurs. To do.

FIG. 2 is a flowchart illustrating the transient control executed by the control unit 10, and this control is repeatedly executed at regular intervals. First, in step S1, it is determined whether or not an overshoot of the actual input rotational speed has occurred. The determination method, for example, in FIG. 3, when the initial actual input revolution speed (solid line) to zoom aims to target input revolution speed Npri _{* a} is below the target input rotation speed Npri _{* a} indicated by a broken line, An overshoot detection input rotation speed Nprio obtained by adding a threshold value α to the target input rotation speed Npri _* a is obtained, and an actual input rotation speed indicated by an upward arrow and an overshoot detection input rotation speed Nprio in FIG. Are compared, and when it is determined that the actual input rotational speed exceeds the input rotational speed Nprio for overshoot detection, it is determined that overshoot has occurred, and the process proceeds to step S2.
On the other hand, when it is not determined that the overshoot has occurred (No), the process returns to step S1 again, and the occurrence of the overshoot is continuously monitored.

If an overshoot occurs (Yes), the process proceeds to step S2, and the countdown timer Tr is set to a predetermined time Th for the purpose described later. In the next step S3, it is determined whether or not the actual input rotational speed Nprij has reached the maximum value (peak rotational speed). For example, as shown in FIG. 3, the change in the actual input rotational speed per unit time (Δnprij / Δt) becomes less than 0 and the increased actual input rotational speed Nprij decreases as shown in FIG. If it turns, it is determined that the peak rotational speed has been reached.
If it is not determined that the peak rotational speed has been reached (No), the process returns to step S3 and waits until the peak rotational speed is reached. On the other hand, if it is determined that the peak rotational speed has been reached (Yes), the process proceeds to step S4.

  The processing unit A composed of the above steps S1 to S3 constitutes an overshoot detection means in the present invention.

In step S4, a target input rotation speed initial value is calculated. This initial value of the target input speed may be any value that exceeds the target input speed Npri _* a in the overshoot direction. For example, as in the present embodiment, the peak rotational speed Nprij_p detected in step S3 may be used, or the overshoot detection input rotational speed Nprio may be used.
The processing unit B composed of the above step S4 constitutes a part of the temporary target input rotational speed calculation means in the present invention, and substitutes this target input rotational speed initial value Nprij_p for the temporary target input rotational speed Npri _* k. .

In the next step S5, it is determined whether or not the target input rotational speed has changed. For example, if the target input speed is no longer Npri _* a due to, for example, the driver further depressing the accelerator pedal (Yes), Steps S6 and S7 are omitted, and the process proceeds to Step S8. As shown in FIG. Decrease the target input speed Npri _* k so that it matches the target input speed after fluctuation.

If it is determined in step S5 that the target input speed is stable at Npri _* a (No), the process proceeds to step S6, and the temporary target input speed Npri _* k is maintained at the target input speed initial value Nprij_p. At the same time, the countdown timer Tr set at the predetermined time Th in the previous step S2 is started (countdown start), and the temporary target input rotation speed Npri _* k is maintained until the countdown is completed.

In the next step S7, it is determined whether or not the countdown timer Tr has been counted down to 0, that is, whether or not the maintenance time measured in the previous step S6 has reached a certain time Th. If not reached (No), the process returns to Step S7 again, waits until the countdown is completed, and maintains the temporary target input rotational speed Npri _* k at the peak rotational speed Nprij_p. On the other hand, when the countdown timer Tr reaches 0 (Yes), the process proceeds to step S8.
The processing unit C composed of the above steps S5 to S7 constitutes a part of the temporary target input rotational speed calculation means in the present invention.

After the tentative target input rotation speed Npri _{* k} fixed time Th maintain the peak rotational speed Nprij_p, step S8 to gradually changed toward the tentative target input rotation speed Npri _{* k} to the target input rotation speed Npri _{* a,} The rotational speed reduction rate ΔNpri _* / Δt per unit time is calculated in advance. As a calculation method, for example, a deviation between the target input rotation speed initial value calculated in the previous step S4 and the target input rotation speed Npri _* a is obtained, and this deviation is multiplied by an arbitrary coefficient K% to obtain a rotation speed reduction rate ΔNpri _*. / Δt [rpm / sec].
Alternatively, the rotational speed reduction rate ΔNpri _* / Δt is set to a target input within the range where the absolute value of the speed reduction rate is less than the constant value Dmax and acceleration / deceleration shock due to a sudden return of the actual input rotational speed Nprij immediately after the occurrence of overshoot does not occur. It may be determined so that the initial rotational speed value matches the target input rotational speed Npri _* a as quickly as possible.

In the next step S9, the temporary target input rotational speed Npri _* k after the maintenance is calculated. As a calculation method, the elapsed time from the countdown end time is multiplied by the rotational speed reduction rate Δnpri _* / Δt to obtain the rotational speed reduction amount Npri, and the rotational speed reduction amount Npri is subtracted from the target input rotational speed initial value Nprij_p. Then, the temporary target input rotation speed Npri _* k is obtained.

In the next step S10, it is determined whether or not the temporary target input speed Npri _* k calculated in the previous step S9 substantially matches the target input speed Npri _* a. As a determination method, for example, the determination is made based on whether or not the difference between the temporary target input speed Npri _* k newly obtained in step S9 and the target input speed Npri _* a is equal to or less than a predetermined threshold value F.
When it is determined that the difference is equal to or less than the threshold value F (Yes), the temporary target input rotation speed substantially coincides with the target input rotation speed, and the transient control is terminated. On the other hand, when it is not determined that the transient control has been completed (No), the process returns to step S4 and the above steps S4 to S10 are repeated.

  The processing unit D composed of the above steps S8 to S10 constitutes a part of the temporary target input rotational speed calculation means in the present invention.

Next, the effect of the transient control described above will be described.
FIG. 4 is a shift pattern diagram showing on the shift map the input rotation speed of the continuously variable transmission that is changed by the shift control according to this embodiment, and FIGS. 5A and 5B are time charts thereof.
Also in this embodiment, in the moderate normal speed change control, as shown in FIGS. 7 and 8A and 8B, the actual input rotational speed Nprij is changed from the position corresponding to Tvo = 0/8 to Tvo = 4/8. It rises to the position corresponding to, and does not rise beyond the position corresponding to Tvo = 4/8.
On the other hand, in this embodiment, in the rapid shift control, the input rotational speed indicated by the solid line in FIGS. 4 and 5A and 5B rises more rapidly than the normal shift control indicated by the alternate long and short dash line, and the actual input rotation The number Nprij once rises beyond the target input rotational speed Npri _* a corresponding to the position of Tvo = 4/8.

At this time, it is determined in step S1 that an overshoot has occurred, and transient control is executed. That is, during the transient control, the temporary target input speed is set, and the actual input speed Nprij is controlled using the temporary target input speed instead of the target input speed Npri _* a. The temporary target input rotational speed is first changed from the actual input rotational speed Nprij to the target input rotational speed initial value, and then gradually changed toward the target input rotational speed.
In FIG. 5B, the temporary target input rotation speed is maintained at the target input rotation speed initial value Nprij_p for the first fixed time Th, and the actual input rotation speed Nprij is also maintained at the target input rotation speed initial value Nprij_p.
After the predetermined time Th has elapsed, the temporary target input speed Npri _* k is gradually made to coincide with the target input speed Npri _* a. The actual input speed Nprij also gradually decreases following the temporary target input speed Npri _* k and converges to the target input speed Npri _* a.
Therefore, in this embodiment, the actual input rotation speed Nprij is allowed to exceed the target input rotation speed Npri _* a, but the acceleration / deceleration shock is caused by the sudden change in the actual input rotation speed Nprij thereafter. It is possible to prevent problems that occur and impair drivability.

In addition, according to the present embodiment, as shown in FIGS. 6A and 6B, at a certain time t _f during which the temporary target input rotational speed is maintained at the initial value of the target input rotational speed, the driver If the accelerator pedal is further depressed and the throttle opening Tvo is further opened (γ in the figure), the target input speed fluctuates and is no longer Npri _* a. The effect of.
That is, if the target input speed is not stable and the target input speed starts increasing from Npri _* a as indicated by β * in the figure, No is selected in step S5 and the process proceeds to step S8. discontinue maintenance of the target input rotation speed Npri _{* k,} tentative target input rotation speed Npri _{* k} reduces the tentative target input rotation speed Npri _{* k} to match the target input rotational speed (in FIG beta *). As a result, the actual input rotational speed Nprij controlled to follow the temporary target input rotational speed Npri _* k converges to the changing target input rotational speed (β * in the figure) as indicated by β in the figure. After the actual input rotation speed Nprij matches the target input rotation speed at time tc, the actual input rotation speed Nprij (β in the figure) increases along the increasing target input rotation speed (β * in the figure).
Therefore, in the present embodiment, the actual input rotational speed Nprij can be quickly followed by a further accelerator operation immediately after the shift.

By the way, according to the above-described embodiment, there is provided a means for detecting an overshoot in which the actual input rotation speed Nprij exceeds the target input rotation speed Npri _* a during the transition period during the shift control, and an overshoot occurs. Then, the process proceeds to the transient control shown in the flowchart of FIG.
During this transient control, a temporary target input rotational speed Npri _* k exceeding the overshoot direction is set, and this temporary target input rotational speed Npri _* k is gradually changed toward the target input rotational speed Npri _* a. The continuously variable transmission is shift-controlled so that the target input speed Nprij follows the temporary target input speed Npri _* k.
For this reason, after the overshoot occurs, the actual target input speed Nprij gradually converges to the target input speed Npri _* a, and a sudden drop in engine speed after the overshoot occurs is eliminated.
Therefore, acceleration / deceleration shocks cannot occur during sudden shift control, and the driver will not be aware of the occurrence of overshoot, preventing sudden fluctuations in actual input rotation and achieving both drivability and fuel efficiency requirements. be able to.
Then, without sacrificing the acceleration response as in the conventional example, it is possible to allow the occurrence of overshoot while keeping the acceleration response as it is, and to prevent the subsequent change in the actual input rotational speed from causing a shock.
In addition to the present embodiment in which the first temporary target input rotational speed Npri _* k (target input rotational speed initial value) is set to the peak rotational speed Nprij_p, the first temporary target input rotational speed Npri _* k (target input rotational speed initial) (Value) may be a value that exceeds the overshoot direction, and can achieve the above purpose even if there is a difference in degree.

In the present embodiment described above, the state in which the actual input rotational speed Nprij was below the initial target input rotation speed Npri _{* a,} the description has been given of the overshoot which exceeds the target input rotation speed Npri _{* a,} conversely , from the state where the actual input revolution speed Nprij had exceeded initially the target input rotation speed Npri _{* a,} even the idea of the present invention for the case of the (also referred to as undershoot) generating overshoot below the target input rotation speed Npri _{* a} When applied, the same effects can be obtained.

In this embodiment, since the peak rotational speed Nprij_p of the actual input rotational speed Nprij is set as the initial target rotational speed value of the temporary target input rotational speed Npri _* k, control according to overshoot becomes possible. Can be played perfectly.

In the present embodiment, the target input speed Npri _* a is stable when the temporary target input speed Npri _* k is gradually changed from the target input speed initial value to the target input speed Npri _* a. Therefore, since the target input rotation initial value Nprij_p is maintained at the predetermined time Th, the actual input rotation speed Nprij also maintains the predetermined time Nprij_p, and the actual input rotation speed Nprij is accelerated / decelerated without decreasing immediately after the overshoot occurs. The occurrence of shock can be effectively prevented.
On the other hand, when the target input rotation speed Npri _{* a} is determined not to be stable, without maintaining a tentative target input rotation speed Npri _{* k,} the target input after variation by reducing the provisional target input rotation speed Npri _{* k} Since it matches the rotation speed, the drivability can be improved, and at the same time, the accelerator operation immediately after the shift can be quickly followed.

In this embodiment, when the temporary target input speed Npri _* k is gradually changed from the initial value of the target input speed toward the target input speed Npri _* a, the absolute value of the speed reduction rate ΔNpri _* / Δt is calculated _. Alternatively, it may be determined to be as large as possible below a certain value Dmax so as to prevent the actual input rotation speed Nprij from dropping sharply and maintain the drivability.
Thereby, the followability of the actual input rotation speed Nprij toward the target input rotation speed Npri _* a can be improved.

Further, by calculating the rotational speed reduction rate ΔNpri _* / Δt based on the deviation between the target input rotational speed Npri _* a and the target input rotational speed initial value Npri _* k, if the deviation is large, the rotational speed reduction rate The absolute value can be increased, and the temporary target input speed Npri _* a can be made to coincide with the target input speed Npri _* a after a predetermined time regardless of the peak speed, and the target input speed Npri. _* The followability of the actual input speed Nprij toward a can be improved.

1 is a schematic system diagram showing a power train of a vehicle equipped with a continuously variable transmission including a transmission control device according to an embodiment of the present invention, together with its control system. It is a flowchart which shows the program of the transient control which the control unit of the Example performs. FIG. 6 is a shift pattern diagram showing overshoot determination and peak rotation determination. It is a shift pattern figure which shows the change state of the input rotation speed by the transient control of the shift control apparatus which becomes the Example. It is operation | movement explanatory drawing which shows the change condition of the input rotation speed by the transient control of the speed-change control apparatus which becomes the same Example, (a) is a time chart of throttle opening, (b) is a target input rotation speed, an actual input rotation speed, It is a comparative time chart. In the transient control of the speed change control device according to the embodiment, at a certain time while the temporary target input speed is maintained at the initial value of the target input speed, the throttle opening further increases and the target input speed fluctuates. FIG. 6 is an operation explanatory diagram showing a change state of the input rotational speed in the case, (a) is a time chart of the throttle opening, (b) is a comparative time chart of the target input rotational speed and the actual input rotational speed. It is a shift pattern diagram showing a change state of the input rotation speed in the gradual normal shift control. It is operation | movement explanatory drawing which shows the change condition of the input rotation speed in loose normal transmission control, (a) is a time chart of throttle opening, (b) is a comparison time chart of target input rotation speed and actual input rotation speed It is. FIG. 10 is a shift pattern diagram showing a change state of an input rotational speed in a sudden shift control by a conventional shift control device. It is operation | movement explanatory drawing which shows the change condition of input rotational speed about the rapid transmission control by the conventional transmission control apparatus, (a) is a time chart of throttle opening Tvo, (b) is target input rotational speed, real input rotational speed, It is a comparative time chart.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Continuously variable transmission 3 Torque converter 4 Primary pulley 5 Secondary pulley 6 V belt 7 Drive gear set 8 Differential gear device 9 Shift control hydraulic circuit 10 Control unit 11 Throttle opening sensor 12 Vehicle speed sensor 13 Input rotation speed sensor

Claims (5)

In the transmission control device for a continuously variable transmission that controls the shift of the continuously variable transmission so that the actual input rotational speed of the continuously variable transmission follows the target input rotational speed determined according to the driving state of the vehicle,
Overshoot detection means for detecting that the actual input rotational speed exceeds the target input rotational speed during a transition period during the shift control;
When overshoot is detected by the means, a temporary target input for obtaining a temporary target input rotational speed that gradually changes from the initial value of the target input rotational speed exceeding the target input rotational speed toward the target input rotational speed. A rotational speed calculating means,
A shift control device for a continuously variable transmission, wherein the shift control is performed using the temporary target input rotation speed instead of the target input rotation speed when the overshoot is detected. The transmission control device for a continuously variable transmission according to claim 1,
The temporary target input rotational speed calculation means determines the peak value of the actual input rotational speed when the overshoot is detected as the initial value of the target input rotational speed. . The transmission control device for a continuously variable transmission according to claim 1 or 2,
The temporary target input rotational speed calculation means maintains the temporary target input rotational speed at the initial value of the target input rotational speed for a set time while the target input rotational speed is stable, and then gradually increases the target input rotational speed. A speed change control device for a continuously variable transmission, characterized in that it is changed toward the number. The transmission control apparatus for a continuously variable transmission according to any one of claims 1 to 3,
The temporary target input rotational speed calculation means is configured to change a temporary target input rotational speed when the temporary target input rotational speed is gradually changed from the initial value of the target input rotational speed to converge to the target input rotational speed, A transmission control device for a continuously variable transmission, which is set to be as large as possible within a range in which no shock occurs. The transmission control device for a continuously variable transmission according to any one of claims 1 to 4,
The temporary target input rotational speed calculation means is configured to change a temporary target input rotational speed when the temporary target input rotational speed is gradually changed from the initial value of the target input rotational speed to converge to the target input rotational speed, A transmission control apparatus for a continuously variable transmission, characterized in that it is determined based on a deviation between the temporary target input rotation speed initial value and the target input rotation speed.

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