JPH03229053A - Control method for continuously variable transmission - Google Patents

Abstract

PURPOSE:To optimize the control by making a control part to start its throttle transient control when throttle opening has become more than the throttle opening trigger value and throttle opening variable speed more than the throttle opening variable speed trigger value, respectively. CONSTITUTION:In this method, there is provided a control part 84 which receives inputted car speed and throttle opening and performs its throttle transient control to change the final desired engine speed by a rate limit value larger than the specified rate limit value. When the actual throttle opening has come more than the throttle opening trigger value being determined by car speed and throttle opening, and throttle opening variable speed more than the throttle opening variable speed trigger value, respectively, it is constituted so as to start the throttle transient control by this control part 84.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a continuously variable transmission control method, and particularly when the actual throttle opening is greater than or equal to the throttle opening trigger value determined from the vehicle speed and the throttle opening. Continuous variable control that starts throttle transient control to change the final target engine speed by a rate limit value greater than a predetermined rate limit value when the throttle opening change rate exceeds the throttle opening change rate trigger value. The present invention relates to a transmission control method.

[Prior Art] In a vehicle, a transmission is interposed between an internal combustion engine and drive wheels. This transmission changes the driving force and running speed of the drive wheels in accordance with the widely varying running conditions of the vehicle, thereby making full use of the performance of the internal combustion engine. The transmission includes a fixed pulley part fixed to the rotating shaft and a movable pulley part attached to the rotating shaft so as to be able to approach and separate from the fixed pulley part. There is a continuously variable transmission that transmits power by increasing or decreasing the rotation radius of a belt wrapped around a pulley by increasing or decreasing the width of the groove, thereby changing the speed ratio (belt ratio).

As this continuously variable transmission, for example, Japanese Patent Laid-Open No. 57-18
6856, JP 59-43249, JP 59-77159, JP 61-233256
It is disclosed in the publication No.

In the control of a continuously variable transmission, when the final target engine speed NESPR changes during normal driving, if the difference is greater than a certain value, the rate at which the final target engine speed NESPF is changed by a predetermined rate limit value is set. Performs limit control. However, when changing the driving mode while driving or increasing the throttle opening THR to near full open, the final target engine speed NESP
Due to the large change in F, a problem occurred that could not be addressed with the normal rate limit value.

For this reason, the applicant of the present application has developed a method to compare the time rate of change, which is the rate limit value, to the predetermined time rate of change, which is the predetermined rate limit value, when changing the driving mode while driving or increasing the throttle opening THR to near full open. We have already completed an application for a rotation speed control device for a continuously variable transmission that performs transient control to increase the engine speed and change the final target engine speed to improve the responsiveness of the engine speed.
No. 302733).

[Problems to be Solved by the Invention] However, in the conventional continuously variable transmission control method, the actual throttle opening THR is greater than or equal to the throttle opening trigger value, which is a constant value determined from the vehicle speed and the throttle opening. Since the throttle transient control is started when this occurs, there is an inconvenience that the driver's intention is not reflected in the control.

For example, when driving at high altitudes, the engine torque decreases due to the influence of atmospheric pressure, so unless the throttle opening is increased to keep it high, the vehicle will not be able to travel as well as at low altitudes. As a result, even in situations where throttle transient control is unnecessary,
When the throttle opening crosses the throttle opening trigger value, there is a problem in that throttle transient control is performed regardless of the driver's intention.

In addition, when driving at high altitudes, the throttle opening always exceeds the throttle opening trigger value, making it impossible for the throttle opening to cross the throttle opening trigger value, so throttle transient control is necessary. There was also a problem that the situation was not controlled.

Such problems occur not only when driving at high altitudes, but also when driving uphill or during sports driving.

Furthermore, if the throttle opening trigger value is set to a constant value, there is a problem in that when the throttle opening THR slightly exceeds the throttle opening trigger value, the engine speed suddenly increases.

As a result, problems such as improper execution of throttle transient control and a phenomenon in which the engine speed rises occur, resulting in the inconvenience that the driver's intention is not reflected in the engine speed control and gives the driver a sense of discomfort. There is.

In addition, if a constant trigger value is set and used regardless of the vehicle's driving condition, the throttle opening THR will increase in the low speed range.
If , is small, a situation arises in which it is difficult to enter throttle transient control, resulting in the inconvenience that a sufficient throttle transient effect cannot be obtained.

Furthermore, in the high speed range, contrary to the low speed range, because the throttle opening THR is large, the throttle transient control is frequently entered, and the throttle transient control is performed more than necessary, which may worsen the driving condition. There is this inconvenience.

[Object of the Invention] Therefore, an object of the present invention is to realize a continuously variable transmission control method that can reflect the driver's intention and achieve appropriate throttle transient control that matches the driving state of the vehicle.

[Means for solving the problem] In order to achieve this object, the present invention provides two pulley parts, a fixed pulley part and a movable pulley part attached to the fixed pulley part so as to be able to come into contact with and separate from the fixed pulley part. The rotation radius of the belt wound around both pulleys is increased or decreased by increasing or decreasing the width of the groove between the two pulleys. In a continuously variable transmission control method that performs rate limit control based on a limit value and performs speed change control to change the gear ratio, vehicle speed and throttle opening are input, and a rate limit value greater than the predetermined rate limit value is set to achieve the final goal. A control unit is provided that performs throttle transient control to change the engine speed, and this control unit controls whether the actual throttle opening is equal to or greater than the throttle opening trigger value determined from the vehicle speed and the throttle opening, and if the rate of change in the throttle opening is The present invention is characterized in that the throttle transient control is started when the throttle opening change speed becomes equal to or higher than a trigger value.

[Function] With the above-described configuration, the control section determines that the actual throttle opening is equal to or greater than the throttle opening trigger value determined from the vehicle speed and the throttle opening, and that the rate of change in the throttle opening is the throttle opening. By starting throttle transient control when the rate of change is equal to or greater than the trigger value, throttle transient control can be performed appropriately.

[Examples] Examples of the present invention will be described in detail below based on the drawings.

1 to 4 show embodiments of this invention. Fourth
In the figure, 2 is a belt-driven continuously variable transmission, 2A
is a belt, 4 is a drive side pulley, 6 is a drive side fixed pulley part, 8 is a drive side movable pulley part, 10 is a driven side pulley, 12 is a driven side fixed pulley part, 14 is a driven side movable part This is a pulley piece. The driving pulley 4 has a rotating shaft 16
The driving side fixed pulley piece 6 is fixed to the rotating shaft 1B, and the driving side movable pulley piece 8 is mounted on the rotating shaft 16 so as to be movable in the axial direction of the rotating shaft 1B but not rotatable. Further, similarly to the driving pulley 4, the driven pulley 10 also includes a rotating shaft 17, a fixed driven pulley piece 12, and a movable driven pulley piece 14.

First and second housings 18.20 are attached to the drive side movable pulley piece 8 and the driven side movable pulley piece 14, respectively, and first and second hydraulic chambers 22.24 are formed, respectively. . This second hydraulic chamber 2 is contained in the second hydraulic chamber 24 on the driven side.
A biasing means 26 made of a spring or the like is provided for biasing the second housing 20 in the direction of expansion of the second housing 20.

An oil pump 28 is provided on the rotating shaft 16, and the oil pump 28 is connected to the first and second hydraulic chambers 22,24.
The first oil passages 30 and 30 communicate with each other through second oil passages 30 and 32, and a primary pressure control valve 34, which is a speed change control valve, that controls the primary pressure, which is the input shaft sheave pressure, is interposed in the middle of the first oil passage 30. Further, a third oil passage 30 on the oil pump 28 side than the primary pressure control valve 34 has a
The line pressure (generally 5 to 25 kg) is controlled by the oil passage 36.
/cm2) to a constant pressure (3 to 4 kg/cm2), and a first three-way solenoid valve 42 for primary pressure control is connected to the primary pressure control valve 34 through a fourth oil passage 40. It goes through.

Further, in the middle of the second oil passage 32, a line pressure control valve 44 having a relief valve function for controlling line pressure, which is pump pressure, is communicated through a fifth oil passage 46, and a sixth oil passage The oil passage 48 communicates with a second three-way solenoid valve 50 for controlling line pressure.

Further, a clutch pressure control valve 52 for controlling clutch pressure is communicated with a seventh oil passage 54 in the middle of the second oil passage 32 on the side of the second hydraulic chamber 24 with respect to the communicating portion of the line pressure control valve 44. This clutch pressure control valve 52 is connected to the third-way solenoid valve 5 for clutch pressure control by an eighth oil passage 56.
Connect 8.

Further, the primary pressure control valve 34, the first solenoid valve for primary pressure control 42, the constant pressure control valve 38, the line pressure control valve 44, and the second solenoid valve for line pressure control 50. The clutch pressure control valve 52 and the third solenoid valve 58 for clutch pressure control communicate with each other through a ninth oil passage 60.

The clutch pressure control valve 52 is communicated with the clutch hydraulic chamber 64 of the hydraulic clutch 62 through a tenth oil passage 66, and a pressure sensor 70 is communicated with the tenth oil passage 66 through an eleventh oil passage 68. This pressure sensor 70 can directly detect oil pressure when controlling clutch pressure in hold and start modes, etc.
It contributes when commanding this detected oil pressure to be the target clutch pressure. Furthermore, since the clutch pressure is equal to the line pressure in the drive mode, it also contributes to line pressure control.

An input shaft rotation detection gear 72 is provided on the outside of the first housing 18, and a first rotation detector 74 on the input shaft side is provided near the outer periphery of the input shaft rotation detection gear 72. Further, an output shaft rotation detection gear 7 is provided on the outside of the second housing 20.
6 is provided, and a second rotation detector 78 on the output shaft side is provided near the outer peripheral portion of the output shaft rotation detection gear 76. Then, detection signals from the first rotation detector 74 and the second rotation detector 78 are input to a control section 84, which will be described later, to determine the engine rotation speed and belt ratio.

The hydraulic clutch 62 is provided with an output transmission gear 80, and a third rotation detector 82 for detecting the rotation of the final output shaft is provided near the outer periphery of the gear 80. In other words, the third rotation detector 82 detects the rotation of the final output shaft directly connected to the reduction gear, the differential, the drive shaft, and the tires.
Vehicle speed can be detected. Further, the second rotation detector 7
8 and the third rotation detector 82, the hydraulic clutch 62
It is also possible to detect the rotation before and after the input/output of the clutch, which contributes to detecting the amount of clutch slip.

Furthermore, a control unit 84 is provided for inputting various conditions such as the throttle opening of the carburetor (not shown) of the vehicle, the engine rotation speed from the first to third rotation detectors 74, 78, and 82, and the vehicle speed. 84, the first three-way solenoid valve 42 for primary pressure control and the second three-way solenoid valve 5 for line pressure control.
0, and controls the opening/closing operation of the third three-way solenoid valve 58 for clutch pressure control to perform speed change control.

In detail, the functions of the various signals and input signals input to the control section 84 are as follows: (1) Detection signal of the shaft lever position...The signals requested for each range by the range signals such as P, R, N1D1L, etc. Line pressure and ratio, clutch control, carburetor throttle opening detection signal...
Detects the engine torque from the memory input into the program in advance, determines the target ratio or target engine speed, detects the carburetor idle position, and improves accuracy in correction and control of the carburetor throttle opening sensor. , Accelerator pedal signal: Detects the driver's intention based on the state of depression of the accelerator pedal and determines the direction of control when driving or starting ■, Brake signal: Detects the driver's intention based on the state of depression of the accelerator pedal. Detects the presence and determines the control direction such as clutch disengagement■, Power mode option signal...It is used as an option to make the performance of the vehicle more sporty (or more economical).

This control unit 84 inputs vehicle speed and throttle opening,
Throttle transient control is performed to change the final target engine speed using a rate limit value greater than a predetermined rate limit value, and the actual throttle opening is determined from the vehicle speed and throttle opening. The throttle transient control is started when the speed of change in throttle opening is equal to or higher than the trigger value and the rate of change in throttle opening is equal to or higher than the trigger value.

Further, the control unit 84 changes the rate limit value during throttle transient control according to the input vehicle speed and throttle opening, and changes the throttle opening when performing throttle transient control depending on the vehicle speed. A configuration in which the maximum time for throttle transient control is set based on the vehicle speed and throttle opening, and the final target engine speed during throttle transient control is changed based on the rate limit value, thereby performing appropriate gear change control that matches the running condition of the vehicle. evening.

Specifically, as shown in FIG. 3, the control section 84 inputs the clutch output rotational speed NCO, which is the vehicle speed, and the throttle opening THR of the carburetor (not shown), and sets the rate limit based on the normal rate limit value RLNR. From the control NRRL, first and second throttle transient controls THTR1 and THTR are performed using, for example, two types of first and second rate limit values RLTR1 and RLTR2.
2.

That is, depending on the vehicle speed NGO and the throttle opening THR, there are two maps: throttle transient control tube 1, second throttle trigger curve TRCRVI, T.
RCRV2 is set, and when the throttle opening THR is greater than or equal to a predetermined first throttle opening trigger value THTRG1 and the change rate THD of the throttle opening THR is greater than or equal to the first throttle opening change rate trigger value THDTRG1, the first Throttle transient control is started, and the throttle opening THR is greater than or equal to a predetermined second throttle opening trigger value THTRG2, and the speed of change THD of the throttle opening THR is equal to the second throttle opening change speed trigger value THD.
When TRG is equal to or higher than TRG2, second throttle transient control is started.

That is, the relationship between the throttle opening THR, the first throttle opening trigger value THTRG1, and the first trottle opening trigger curve TRCRVI (NGO) is THR≧THT.
RG1=TRCRV1 (NGO), and the relationship between the speed of change THD of the throttle opening THR and the first throttle opening shifting speed trigger value THDTRGI is THD≧THDT.
When RG 1 is reached, the first throttle transient control THTR1 is performed, and the longest time of the first throttle transient control THTR1 is set to TTRII based on the vehicle speed NCO and the throttle opening THR.

In addition, the throttle opening THR, the second throttle opening trigger value THTRG2, and the second throttle opening trigger curve T
Relationship with RCRV2 (NGO) is THR≧THTRG
2=TRCRV2 (NGO) and throttle opening T
The relationship between the HR change speed THD and the second throttle opening change speed trigger value THDTRG2 is THD≧THDTGR.
2, the second throttle transient control THTR2 is performed, and the longest time of the second throttle transient control THTR2 is set to TTRI2 based on the vehicle speed NCO and the throttle opening THR.

At this time, the first throttle opening trigger value THTRG
1 and the second throttle opening trigger value THTRG2 are T
It is set in advance to satisfy the relationship HTRGI<THTRG2, and the first throttle transient control THTRI is set to be performed at a small throttle opening THR.

Note that 86 is a piston of the hydraulic clutch 62, and 88 is a piston of the hydraulic clutch 62.
90 is a first pressure plate; 92 is a friction plate; 94 is a second pressure plate; 96
is an oil pan, and 98 is an oil filter.

Next, the effect will be explained.

In the belt-driven continuously variable transmission 2, as shown in FIG. 4, an oil pump 28 located on the rotating shaft 16 operates in response to the drive of the rotating shaft 16, and the oil is pumped into an oil pan 96 at the bottom of the transmission. is absorbed through the oil filter 98. The line pressure, which is this pump pressure, is controlled by the line pressure control valve 44, and if the amount of leakage from the line pressure control valve 44, that is, the amount of relief from the line pressure control valve 44 is large, the line pressure will be low; If the line pressure is less than that, the line pressure will be higher.

Next, control of the continuously variable transmission 2 will be explained.

The continuously variable transmission 2 is hydraulically controlled, and ensures appropriate line pressure for belt retention and torque transmission, primary pressure for changing the gear ratio, and clutch engagement based on commands from the control unit 84. The clutch pressure for each is ensured.

Control of the continuously variable transmission 2 will be explained along the flowchart of FIG.

A control program for the continuously variable transmission 2 is started (100) by driving an internal combustion engine (not shown), and a determination is made (102) as to whether the driving mode of the vehicle is a drive mode (DRV MODE). If this judgment (102) is No, perform other ratio control (104) and return (1
06) Let.

If the judgment (102) is YES, the first throttle opening trigger curve TRCRVI (NGO) is
In addition to determining the throttle opening trigger value THTRG1, the second throttle opening throttle opening trigger curve T
A process (108) is performed to determine the second throttle opening trigger value THTRG2 from RCRV2 (NGO).

Next, it is determined whether the relationship between the throttle opening THR and the second throttle opening trigger value THTRG2 is THR≧THTRG2 (110).

If this judgment (110) is YES, the relationship between the speed of change THD of the throttle opening THR and the second throttle opening change speed trigger THDTRG2 is THD≧THDT.
A determination (112) is made as to whether or not it is RG2.

If this determination (112) is YES, a process (114) is performed to subtract 1 from the second throttle transient control timer TTR2.

If the judgment (110) is NO, also the judgment (11)
If 2) is NO, the process of setting the second throttle transient control timer initial value TTR2 to 2 (116
)I do.

The second throttle transient control timer TTR2
After the process (11B), it is determined whether the second throttle transient control timer TTR2 is O or not (11B).
Do 8). If this determination (118) is No, a determination (120) is made as to whether the first throttle transient control timer TTR1 is 0 or not. This judgment (120
) is NO, the process of subtracting 1 from the first throttle transient control timer TTRI (122)
I do.

And this first throttle transient control THT
After the process (122) of R1, a process (124) is performed to set the rate limit value RL to the second rate limit value RLTR2 of the second throttle transient control THTR2, and if the judgment (120) is YES, the process (124) is performed. Processing (122) is bypassed and the process proceeds to processing (124).

Then, the final target engine speed of the previous control loop (
NESPRF) A process (128
)I do.

Further, the second throttle transient control timer T
After processing (116) for TR2 and determining (11)
8) is NO, the slot, 7 torr opening THR and the first
The relationship with the throttle opening trigger value THTRGI is TH
It is determined whether R≧THTRG1 (128).

If this judgment (128) is YES, the relationship between the throttle opening THR change speed THD and the first throttle opening change speed trigger value THDTRG1 is THD
It is determined whether ≧THDTRG1 (130).

If this judgment (130) is YES, a process (132) is performed to subtract 1 from the first throttle transient control timer TTR1, and it is determined whether the first throttle transient control timer TTR1 is O or not. Judgment (13
Do 4).

If this judgment (134) is No, the rate limit value RL is set to the first trottle transient control THTR1.
Processing to set the second rate limit value RLTR2 (136
), and in the process (136), RLTRl is set to the final target engine speed NFSPRH of the previous control loop.
The process moves on to processing (12B) in which the rate limit value RL is added to obtain the final target engine rotation speed NESPRF.

Further, if the judgment (128) is No, or if the judgment (130) is NO, a process (138) of setting the first throttle transient control timer TTR1 to the first throttle transient control timer initial value TTRII.
I do. After this process (138), the above judgment (13)
If 4) is YES, the rate limit value RL is converted to the normal rate limit value RLNR in the normal rate limit control NRRL (140), and the final target engine speed NFSPRH of the previous control loop is changed to the above process. (140), the final target engine rotation speed NFSPRF is obtained by adding the rate limit value RL which is set to RLNR.
The process then proceeds to step 12B.

After each of the above-mentioned processes (126), a process (142) of calculating a target engine speed NESPF by general ratio control is performed. The relationship between the target engine speed NESPF by this general ratio control and the value obtained by adding the rate limit value RL of the processing (124) (136) (140) to the final target engine speed (NESPRF) NESPRN of the previous control loop. However, NESPF≦NESPRN
+ Determine whether or not it is RL (144).

If this determination (144) is YES, a process (14B) is performed in which the final target engine speed NESPRF is set to the target engine speed NESPF by general ratio control.

After the process (14B), the process (148) sets the final target engine speed NESPRF to the final target engine speed (NESPF) NESPRN of the previous control loop.
At the same time, if the judgment (144) is No, the process (146) is bypassed and the final target engine speed NESPRF is set to the final target engine speed (NESPRF) NESPRN of the previous control loop (14).
8).

Thereafter, the program returns (150).

Control of the continuously variable transmission 2 will be explained with reference to the timing chart in FIG. 2.

In FIG. 2, a case where the accelerator is depressed from a low throttle opening THR, for example, a kick-down operation will be explained.

In general ratio control, the engine speed NE is controlled to the final target engine speed NESPRF calculated by the schedule. As a result of the increase in throttle opening THR, a change occurs in the final target engine speed NFSPRF, and if the amount of change in the target engine speed NFSPF, which is obtained by filtering this NFSPF, is greater than or equal to the normal rate limit value RLNR, the rate Limit control NRR
L is done. This rate limit control NRRL is performed from point a in FIG.

The throttle opening THR changes at a rate T at point b.
HD is the first throttle opening change speed trigger value THDTR
G1 or more, but since the throttle excessive THR is less than the first throttle opening trigger value THTRG1, a-b
Between the points, the first throttle transient control is not started, and normal rate limit control NRRL is performed.

When the accelerator is depressed and reaches the 0 point, the throttle opening T
Since HR exceeds the first throttle opening trigger value THTRGI, the first throttle transient control THTR
1 is started.

Even if the throttle opening THR becomes equal to or higher than the second throttle opening trigger value THRTRG2 at point d due to further depression of the accelerator, the throttle opening THR
Since the rate of change THD is less than the second throttle opening rate change trigger value THDTRG2, the second throttle transient control THTR2 is not started.

The second throttle transient control THTR2 is started from point e when the rate of change THD of the throttle opening THR becomes equal to or greater than the second throttle opening rate change trigger value THDTRG2. This second throttle transient control T
HTR2 ends at point f when the second throttle transient control timer initial value TTRI2 by the second throttle transient control timer TTR2 has elapsed;
After that, first throttle transient control is performed.

The first throttle transient control THTRI is the initial value T of the first throttle transient control timer based on the first throttle transient tight TTRI from 0 point.
It ends at point g, where TR11 has elapsed.

From this point g, normal rate limit control NRRL is performed.

At point h, the relationship between the target engine speed NESPF by general ratio control and the value obtained by adding the normal rate limit value RL to the final target engine speed (NESPRF) NESPRN of the previous control loop is NESPRF≦N.
In order to satisfy ESPRN+RL, ratio control is performed according to a schedule to control the engine speed NE to NESPF determined by a filter.

In this way, the control unit 84 determines that the actual throttle opening THR is greater than or equal to the throttle opening trigger value THRTRG determined from the vehicle speed NCO and the throttle opening THR, and the rate of change THD of the throttle opening THR is the throttle opening change rate. By starting the throttle transient control THTR when the trigger value THDTRG or more is reached, the throttle transient control THTR can be appropriately performed.

For this reason, throttle transient control THTR can be used when unnecessary during high-altitude driving, on-hill driving, sports driving, etc.
It is possible to prevent the inconvenience that the throttle transient control THTR is performed, and also to avoid the inconvenience that the throttle transient control THTR is not performed when necessary, so the throttle transient control THTR can be performed in a wider throttle opening range, and the improper execution of the throttle transient control THTR can be avoided. It is possible to reliably prevent malfunctions such as engine speed and engine speed spikes, reflect the driver's intentions in engine speed control, and eliminate the risk of causing discomfort to the driver. Fine control can be achieved and driving performance can be improved.

Further, the throttle opening trigger value TH is determined according to the vehicle speed NCO and the throttle opening THR input to the control unit 84.
By setting and using RTRG, it is possible to avoid the situation where it is difficult to enter throttle transient control THTR in the low speed range, and it is possible to obtain a sufficient throttle transient effect, and at the same time, in the high speed range, throttle transient control THTR is performed more than necessary. There is no need to worry, and driving performance can be improved.

Note that the present invention is not limited to the above-described embodiments, and various modifications can be made.

For example, in the embodiment of the present invention, the throttle transient control THTR is made into two first and second throttle transient controls THTR1 and THTR2, and the relationship between the rate limit value and the maximum time of the throttle transient control is - I explained it as a picture match, but
It can be set to perform three or more throttle transient controls, and various combinations of the rate limit value and the maximum time of throttle transient control can be set.

[Effects of the Invention] As described in detail above, according to the present invention, the control unit controls the control unit to ensure that the actual throttle opening is equal to or greater than the throttle opening trigger value determined from the vehicle speed and the throttle opening and the rate of change of the throttle opening is controlled by the controller. By starting the throttle transient control when the throttle opening change speed becomes equal to or greater than the throttle opening change speed trigger value, the throttle transient control can be appropriately performed.

Therefore, it is possible to prevent the inconvenience of throttle transient control being performed when unnecessary, such as when driving at high altitudes, on a pitched road, or during sports driving, and it is also possible to avoid the inconvenience of throttle transient control not being performed when necessary.
Throttle transient control can be performed over a wider throttle opening range, reliably preventing malfunctions such as improper execution of throttle transient control and rapid rise in engine speed, and ensuring that the driver's intention is not affected. It can be reflected in number control, and
It is possible to perform fine-grained control without causing a sense of discomfort to the driver, and to perform appropriate throttle transient control that matches the driving conditions of the vehicle, thereby improving driving performance.

[Brief explanation of drawings]

1 to 4 show embodiments of the present invention, FIG. 1 is a flow chart of control of a continuously variable transmission, FIG. 2 is a timing chart of control of a continuously variable transmission, and FIG. 3 is a control flow chart of a continuously variable transmission. Control Block Diagram FIG. 4 is a block diagram of the continuously variable transmission. In the figure, 2 is a belt-driven continuously variable transmission, 2A is a belt, 4 is a drive pulley, and 10 is a driven side boot 1 hub.
30 is a first oil passage, 32 is a second oil passage, 34 is a primary pressure control valve, 36 is a third oil passage, 38 is a constant pressure control valve, 40 is a fourth oil passage, 42 is a first three-way solenoid valve, 44 4 is a line pressure control valve, 46 is a fifth oil passage, and 4 is a line pressure control valve.
8 is the sixth oil passage, 50 is the second three-way solenoid valve, 52 is the clutch pressure control valve, 54 is the seventh oil passage, 56 is the eighth oil passage, 58 is the third three-way solenoid valve, and 60 is the ninth oil passage. , 62 is a hydraulic clutch, 66 is a tenth oil passage, 6
8 is the eleventh oil passage, 70 is the pressure sensor, and 74 is the first oil passage.
A rotation detector, 78 is a second rotation detector, 82 is a third rotation detector, and 84 is a control section. Patent Applicant Patent Applicant

Claims (1)

[Claims] 1. The radius of rotation of the belt wound around both pulleys can be increased by decreasing or increasing the groove width between the fixed pulley piece and the movable pulley piece that is attached to the fixed pulley piece so as to be able to move toward and away from the fixed pulley piece. Continuously variable transmission that performs rate limit control using a predetermined rate limit value to change the gear ratio when there is a change in the target engine speed calculated from the vehicle speed and throttle opening while driving. In the engine control method, a control section is provided which inputs the vehicle speed and the throttle opening degree and performs throttle transient control to change the final target engine speed by a rate limit value larger than the predetermined rate limit value, and the control section The throttle transient control is started when the actual throttle opening is greater than or equal to a throttle opening trigger value determined from the vehicle speed and throttle opening, and the rate of change in the throttle opening is greater than or equal to the throttle opening change rate trigger value. A continuously variable transmission control method characterized by: