JP3536430B2 - 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 a control device for a continuously variable transmission, and in particular, when the accelerator pedal is repeatedly depressed and released on a curved uphill road, the engine speed increases unnecessarily. The present invention is suitable for realizing good drivability by preventing the repeated reduction and by enabling the engine braking according to the degree of the downward gradient when traveling on a downhill road.

[0002]

2. Description of the Related Art Generally, in a conventional belt type or toroidal type continuously variable transmission, a vehicle speed and a throttle opening are taken as variables, and a variable speed correlation which can set a target input speed of the continuously variable transmission from these variables. The target input speed is set by using a control map in which the target vehicle speed, that is, the output speed of the continuously variable transmission is set at the present vehicle speed. The speed reduction ratio) is controlled.
The target input speed is set to be small when the throttle opening is small, that is, when the engine load is small, and is large when the throttle opening is large, that is, when the engine load is large.

For this reason, for example, while traveling on a curved uphill road, the accelerator pedal is greatly depressed in order to travel along a straight slope portion, and before the curved portion, the accelerator pedal is released for deceleration and the brake pedal is depressed. In a driving state in which the accelerator pedal is repeatedly stepped on and released, such as when the accelerator pedal is stepped on again after passing through the bent portion, the accelerator pedal is depressed and the throttle opening is changed even at the same vehicle speed. As the speed increases, the target input speed increases so that the gear ratio (vehicle speed reduction ratio) increases. As a result, the engine speed increases, and when the accelerator pedal is released and the throttle opening decreases, the speed ratio (vehicle speed reduction ratio) increases. ) Becomes smaller, the target input speed becomes smaller, and as a result, the engine speed decreases. Therefore, there is a sense of discomfort in terms of noise and vibration (hereinafter, these are also collectively referred to as sound and vibration), and when the accelerator pedal is depressed from the released state, that is, the target input rotational speed is small. When shifting from the state to the large state, the output (torque) of the engine is consumed only to increase the engine speed, and therefore the engine speed that satisfies the predetermined target input speed There is also a problem that a desired driving force cannot be obtained even when the accelerator pedal is depressed until the number of the driving force reaches the maximum.

[0004]

In order to solve such a problem, the applicant of the present invention has previously disclosed a control device for a continuously variable transmission described in Japanese Patent Application No. 5-218736 (hereinafter referred to as a first conventional example). (Also noted). This control device for a continuously variable transmission discloses a technique for limiting the minimum value of the target engine speed (equivalent to the above-mentioned target input speed) when the traveling load is large. According to this, since the traveling load becomes large when traveling on the uphill road as described above, the minimum value of the target engine rotational speed is limited to the rotational speed that does not fall below the rotational speed corresponding to the traveling load. Even if the accelerator pedal is repeatedly stepped on and released, the engine speed will not decrease more than necessary, and the problem of noise and vibration as described above and the desired drive when the pedal is released again from the accelerator pedal released state The problem of not getting power does not occur. However, since the traveling load is reduced when traveling on a downhill road, the minimum value of the target engine speed is practically not limited particularly when traveling on a steep downhill. However, since the engine speed is reduced and the engine braking force is reduced, the desired vehicle deceleration cannot be obtained.

In order to solve the problem of the engine braking force on the downhill road, for example, a control device for a continuously variable transmission described in JP-A-1-148630 (hereinafter, also referred to as a second conventional example) is applied. be able to. This control device for a continuously variable transmission detects a downward slope of a traveling road, and according to the magnitude of the gradient state amount, a shift restriction area (minimum vehicle reduction ratio) side of a shift correlation (shift pattern) on the side of a minimum shift ratio. There is disclosed a technique for providing. Therefore, when traveling on a downhill road as described above, the minimum value of the gear ratio of the continuously variable transmission is limited in accordance with the magnitude of the downward gradient state amount, so that the target input speed (target engine speed) is reduced. Is restricted, and as a result, the engine speed is regulated so as to increase, the engine braking force increases, and the vehicle deceleration can be increased in accordance with the amount of downward gradient state.

Therefore, by combining the first conventional example and the second conventional example, it is possible to individually solve each problem when traveling on an uphill road and each problem when traveling on a downhill road. However, in the first conventional example, it is necessary to determine the uphill slope corresponding to the running load and detect the gradient state quantity, and in the second conventional example, it is necessary to determine the downhill slope and detect the gradient state quantity. Further, since it is necessary to carry out individual gear ratio control for the uphill gradient and the downhill gradient, the configuration and arithmetic processing therefor become complicated, which is also disadvantageous in terms of cost.

Further, particularly in the first conventional example, when the minimum value of the target input speed changes from a value equal to or lower than the actual input speed to a value higher than the actual input speed due to an increase in running load, that is, an amount of uphill gradient, Even when the driver does not operate the accelerator pedal, or more specifically, the accelerator pedal is not depressed, a so-called downshift is performed to increase the gear ratio (vehicle reduction ratio) more than the decrease in vehicle speed. However, there is also a problem in that the number of revolutions of the engine is arbitrarily increased and the occupant feels uncomfortable.

The present invention has been developed in view of these problems, and is advantageous in terms of cost by simplifying the configuration and arithmetic processing, and further, the engine according to various running states and accelerator pedal operating states. It is an object of the present invention to provide a control device for a continuously variable transmission that can solve the problem of sound vibration and the problem of discomfort to the occupant by controlling the fluctuation of the rotation speed of the vehicle.

[0009]

And Thus SUMMARY OF THE INVENTION The control device for a continuously variable transmission according to claim 1 of the present invention, as shown in the basic diagram of Fig. 1 a, detects the opening of the throttle valve Throttle opening detecting means, vehicle speed detecting means for detecting the vehicle speed, and a gear change correlation capable of setting a target input speed to the continuously variable transmission mounted on the vehicle in advance with the throttle opening and the vehicle speed as variables. A target input speed to the continuously variable transmission from at least the throttle opening detection value detected by the throttle opening detection means and the vehicle speed detection value detected by the vehicle speed detection means based on the shift correlation. A control device for a continuously variable transmission, which includes a gear ratio control means for controlling a gear ratio of the continuously variable transmission to set and achieve a set target input speed, detects a gradient state quantity of a traveling road. Gradient state quantity detection And a gear ratio control means, wherein the target input rotation speed to be achieved by the continuously variable transmission corresponds to an absolute value of a gradient state quantity detection value detected by the gradient state quantity detecting means. It comprises a target input rotational speed limiting means for limiting to be no preset predetermined value lower by the rotation speed follows than the number or the rotational speed, the target input
The force rotation speed limiting means measures the vehicle speed and the gradient state quantity of the road in advance.
Is the minimum limit of the input speed to the continuously variable transmission.
It has a minimum number of rotations that can be set, and the minimum number of rotations.
Vehicle speed detection detected by the vehicle speed detection means based on correlation
Value and gradient state quantity detection detected by gradient state quantity detection means
Target input corresponding to the running load speed from the absolute value
Set the minimum speed limit and set the maximum target input speed.
Target input rotation set from the small limit value and the shift correlation
Either the number or the smaller one is reached by the continuously variable transmission.
Target input speed regulation set to the target input speed to be achieved
It is characterized by having means .

[0010]

A control device for a continuously variable transmission according to a second aspect of the present invention comprises an input speed detecting means for detecting an input speed of the continuously variable transmission, and the target input speed limiting means. Means that the detected throttle opening value detected by the throttle opening detection means is equal to or more than a predetermined value, and the target input rotation speed set by the target input rotation speed regulation means due to a change in the slope condition of the road is When the input rotation speed detection value detected by the rotation speed detection means or higher is reached, the target input rotation speed to be achieved by the continuously variable transmission is limited to the input rotation speed lower than the input rotation speed detection value. It is a feature.

According to a third aspect of the present invention, in the control device for a continuously variable transmission according to the third aspect of the present invention, the target input speed limiting means is configured so that the throttle opening detection value detected by the throttle opening detecting means is in the closing direction. The target input speed to be achieved by the continuously variable transmission is held at the input speed detection value before the throttle opening change detected by the input speed detection means. Is.

According to a fourth aspect of the present invention, in the control device for a continuously variable transmission according to the fourth aspect of the present invention, the target input speed limiting means has a throttle opening detection value detected by the throttle opening detection means in a closing direction. The target input rotational speed to be achieved by the continuously variable transmission, the input rotational speed detection value detected by the input rotational speed detection means, and the target input rotational speed set by the target input rotational speed regulating means. It is characterized in that the input rotational speed is limited to the smaller one of the rotational speeds.

The control device for a continuously variable transmission according to a fifth aspect of the present invention includes vehicle acceleration detecting means for detecting the acceleration of the vehicle, and acceleration change rate detecting means for detecting the change rate of the acceleration of the vehicle. The target input speed limiting means is set by the target input speed regulating means due to a change in the slope condition of the traveling road when the throttle opening detection value detected by the throttle opening detecting means is a predetermined value or less. When the target input rotation speed thus determined becomes equal to or higher than the input rotation speed detection value detected by the input rotation speed detection means, the vehicle acceleration detection value detected by the vehicle acceleration detection means is Until the acceleration change rate detection value detected by the acceleration change rate detection means is equal to or higher than a predetermined value and is equal to or lower than a predetermined value, the target input rotation speed to be achieved by the continuously variable transmission is
It is characterized in that the input rotation speed is limited to the input rotation speed detection value or less.

A control device for a continuously variable transmission according to claim 6 of the present invention, as shown in the basic configuration diagram of FIG.
Throttle opening detection that detects the opening of the throttle valve
Means, vehicle speed detecting means for detecting the vehicle speed, and a slot in advance.
Continuously variable transmission mounted on the vehicle with variable opening and vehicle speed
There is a gear shift correlation that can set the target input speed to the machine.
The throttle based on at least the shift correlation
The throttle opening detection value detected by the opening detection means and
From the vehicle speed detection value detected by the vehicle speed detection means,
Set the target input speed to the transmission and set the target input speed.
Control the gear ratio of the continuously variable transmission to achieve the power rotation speed.
In a control device for a continuously variable transmission equipped with
And a gradient state quantity detection hand that detects the gradient state quantity of the road.
The gear ratio control means is achieved by the continuously variable transmission.
The target input speed to be achieved is determined by the gradient state quantity detecting means.
Running negative corresponding to the absolute value of the detected gradient state quantity
The number of rotations of the load or a predetermined value that is preset from the number of rotations
Target input speed that is restricted so that it does not drop below a low speed
The target input rotation speed limiting means sets a minimum limit value of the throttle opening from the absolute value of the gradient state quantity detection value detected by the gradient state quantity detecting means, A throttle that sets a minimum limit value or a throttle opening detection value detected by the throttle opening detection means, whichever is not smaller, as a variable of the throttle opening for setting a target input speed from the shift correlation. It is characterized in that it is provided with an opening control means.

[0016]

In the control device for a continuously variable transmission according to claim 1 of the present invention having the above-described structure, as shown in the basic configuration diagram of FIG. Is a target to be achieved by the continuously variable transmission so that the rotational speed does not become equal to or lower than the traveling load rotation speed corresponding to the absolute value of the gradient state amount detection value of the traveling road or the rotation speed lower than the rotation speed by a preset value. Limit the input speed. Here, the running load rotational speed corresponding to the absolute value of the gradient state amount detection value of the traveling road is the input rotational speed of the continuously variable transmission necessary for traveling through the traveling road or the rotational speed of the engine equivalent thereto. , But
For example, even if the detected value of the gradient state amount on the uphill is a positive value and the detected value of the gradient state amount on the downhill is a negative value, the engine speed (torque) required to climb the uphill is also decreased. The number of revolutions to obtain the required engine braking force on a slope also has a strong correlation with the absolute value of the gradient state quantity. More specifically, the larger the absolute value of the gradient state quantity, the more positive or negative the output torque is. Regardless of this, it is sufficient if the engine speed is high.
Therefore, the target input speed that should be achieved by the continuously variable transmission should be limited so that the speed does not drop below the running load speed equivalent to the engine speed that corresponds to the absolute value of the gradient state amount detection value of this running path. By controlling the gear ratio (vehicle speed reduction ratio) of the continuously variable transmission, even if the accelerator pedal is repeatedly depressed and released frequently when traveling on a curved uphill road, the engine speed decreases more than necessary, or Not only does it not increase significantly from the reduced state more than necessary, it is not only favorable for sound vibration, but also when the accelerator pedal is depressed from the released state of the accelerator pedal, it is not only for increasing the engine speed. Since the output (torque) of the engine is not significantly consumed, a desired driving force can be easily obtained. Further, when traveling on a downhill road, even if the accelerator pedal is released, for example, the target input speed is set to a large value according to the absolute value of the gradient state amount detection value of the traveling road, that is, the continuously variable transmission The gear ratio (vehicle speed reduction ratio) is controlled to a large gear ratio (speed reduction ratio), and the engine speed also becomes a high speed, so that a sufficient engine braking force can be obtained.

It should be noted that the target input speed that should be achieved by the continuously variable transmission is set to a predetermined value which is greater than the running load speed that corresponds to the absolute value of the detected gradient state amount detected by the gradient state amount detecting means. When the engine speed is controlled so as not to be lower than the number of revolutions lower by the value, the engine braking force can be slightly suppressed to prevent the driver from feeling too effective.

Further, prior Symbol target input rotational speed regulating means provided in the target input rotational speed limiting means, said minimum limit input rotational speed of the CVT advance vehicle speed and gradient conditions of the travel path as a variable It has the minimum rotation number correlation that can set the value. This minimum rotation speed correlation is obtained in order to obtain the output (torque) of the engine or the engine braking force necessary to drive through the traveling path of the gradient state amount (absolute value) at the vehicle speed,
Since it is for setting the minimum value of the input speed to the continuously variable transmission through the engine speed as described above, based on the minimum speed correlation, the vehicle speed detection value and the gradient state quantity are determined. The minimum limit value of the target input speed corresponding to the traveling load speed set from the absolute value of the detected value is the engine output sufficient to continue climbing the uphill road at the vehicle speed, or the downhill road. This is the minimum input speed of the continuously variable transmission that can obtain sufficient engine braking force to continue descending at the vehicle speed. Therefore, the smaller one of the minimum limit value of the target input speed and the target input speed set from the gear shift correlation is set as the target input speed to be achieved by the continuously variable transmission. As a result, the gear ratio of the continuously variable transmission (vehicle reduction ratio), that is, the engine speed can be controlled to a suitable state according to the gradient state of the traveling path, the vehicle speed, and the throttle opening.

Further, in the control device for a continuously variable transmission according to a second aspect of the present invention, when the throttle opening detection value is equal to or larger than a predetermined value, the above-described operation is performed according to the change in the gradient condition of the road. Even if the target input speed set in this way becomes equal to or higher than the input speed detection value, the target input speed to be achieved by the continuously variable transmission is limited to the input speed detection value or less, thereby operating Even if a person does not operate the accelerator pedal, a downshift that is executed more than a change in the vehicle speed due to a change in the gradient state amount on the road, that is, an increase in the engine speed is avoided, and an occupant feels uncomfortable. Can be eliminated.

Further, in the control device for a continuously variable transmission according to a third aspect of the present invention, when the throttle opening detection value changes in the closing direction, the target input rotation to be achieved by the continuously variable transmission. By holding the input speed detection value before the throttle opening change, it is possible to avoid a downshift that is executed even when the driver depresses the accelerator pedal, that is, an increase in engine speed. As a result, it is possible to eliminate discomfort to the passengers.

Further, in the control apparatus for a continuously variable transmission according to a fourth aspect of the present invention, when the throttle opening changes in the closing direction, the target input speed that should be achieved by the continuously variable transmission is set. , By limiting to more than the target input speed and the input speed detection value set as described above,
The desired driving force can be quickly obtained.

Further, in the control device for a continuously variable transmission according to a fifth aspect of the present invention, the throttle opening detection value is set to a value equal to or less than a predetermined value, and is set as described above according to a change in slope condition of the traveling road. When the target input rotational speed is equal to or higher than the input rotational speed detection value, the vehicle acceleration detection value is equal to or higher than a predetermined value and the acceleration change rate detection value is equal to or lower than a predetermined value. By setting the target input rotational speed to be equal to or higher than the input rotational speed detection value, a downshift can be executed at a timing desired by the driver to increase the engine rotational speed and obtain an appropriate engine braking force. .

Further, in the control device for a continuously variable transmission according to claim 6 of the present invention, the throttle opening restricting means provided in the target input speed limiting means is an absolute value of the gradient state amount detection value. To set the minimum throttle opening limit value. Since the minimum limit value of the throttle opening is to obtain the output (torque) of the engine or the engine braking force required to drive the traveling road of (the absolute value of) the gradient state amount, this throttle opening Either the minimum limit value of the opening degree or the detected value of the throttle opening degree, whichever is not smaller, is set as a variable of the throttle opening degree that sets the target input speed from the gear shift correlation, so that It is possible to control the gear ratio of the continuously variable transmission (vehicle speed reduction ratio), that is, the engine speed, which is sufficient to drive across the traveling path, to a suitable state, and further, it is possible to reduce the amount of information in the processing area.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the control device for a continuously variable transmission according to the present invention is applied to an actual vehicle will be described below with reference to the drawings. FIG. 2 is a skeleton diagram showing a power transmission mechanism of a continuously variable transmission according to an embodiment of the present invention. The continuously variable transmission of this embodiment is applied to a so-called FF (front engine front drive) vehicle in which the driving wheels that are rotationally driven by the rotational driving force of the engine (that is, the engine) are the front left and right wheels. .

Incidentally, the continuously variable transmission mounted on the vehicle according to the present embodiment is usually an engine brake having a minimum gear ratio larger than the normal running range and the normal running gear ratio control region as a shift position for forward running. When the normal traveling range (generally referred to as the D range) is selected as the gear shift position, the normal traveling speed ratio control region (D range speed ratio region) suitable for the normal traveling as will be described later. ), The engine brake range (generally referred to as 2 range or Ds range and L range or 1 range) is selected within the engine brake range control region (2 range gear ratio region or L range gear ratio region). , The gear ratio of the continuously variable transmission is controlled according to the vehicle speed and the throttle opening, respectively.
Here, only the control mode when the D range is selected will be described in detail.

As shown in FIG. 2, the power transmission mechanism of the continuously variable transmission includes a fluid coupling 12, a forward / reverse switching mechanism 15, a toroidal continuously variable transmission mechanism 40, a gear reduction mechanism 20, and a differential device 22. Etc., and the engine 10
The rotation of the output shaft 10a can be transmitted to the left and right drive shafts 66, 68 at a predetermined gear ratio and rotation direction. The output side of the fluid coupling 12 connected to the output shaft 10a of the engine 10 is connected to the rotary shaft 13 of the forward / reverse switching mechanism 15, and the forward / reverse switching mechanism 15 includes a planetary gear mechanism 17 and a forward drive mechanism. Clutch 1
8 and a reverse brake 19. And
By changing the engagement state of the forward clutch 18 and the reverse brake 19 by a fluid pressure control device (not shown), the rotation direction of the drive shaft 14 can be changed to the forward forward direction or the reverse reverse direction. A so-called normal torque converter can be used for the fluid coupling.

The toroidal type continuously variable transmission 40 is shown in FIG.
As shown in, the input disk 42 and output disk 43 is formed on the toroidal surface as held and pairs facing surfaces of freely coaxially rotate in the housing 41 is circular as viewed in axial section, these disks 42 , 43, a pair of upper and lower transmission rollers 44A, 44B arranged in contact with both toroidal surfaces in a toroidal space formed by the toroidal surfaces.
And trunnions 45A and 45B which hold the transmission rollers 44A and 44B so as to roll along the toroidal surface and are movable in the axial direction, and the trunnions 45.
Fluid pressure cylinders 46a to 46d for moving A and 45B in the axial direction to perform a speed change operation, and an electromagnetic directional control valve 47 for controlling the fluid pressure supplied to these fluid pressure cylinders 46a to 46d are configured. Of these, the input disk 42 is connected to the drive shaft 14, and the output disk 43 is connected to the driven shaft 28. Therefore,
The rotational driving force of the engine 10 decelerated by the toroidal type continuously variable transmission 40 at a predetermined gear ratio is further amplified by deceleration by the gear reduction mechanism 20 from the driven shaft 28,
Further, it is output from the pinion gear of the differential device 22 to the output shafts 66 and 68 via the side gears, respectively.

The electromagnetic directional control valve 47 is constructed at four ports and three positions, the pump port P is connected to the discharge side of the fluid pressure pump 48, the tank port T is connected to the reservoir 49, and one control is provided. The port A is connected to the fluid pressure cylinders 46a and 46c, and the other control port B
Is connected to the fluid pressure cylinders 46b and 46d, the pump ports P and tank ports T are cut off from the control ports A and B at the normal position, and the left electromagnetic solenoid SL is excited at the left offset position. The pump port P is connected to the control port A, the tank port T is connected to the control port B, and the pump port P is located at the control port B and the tank port T is located at the control port A at the right offset position where the right electromagnetic solenoid SR is excited. Connected.

The electromagnetic directional control valve 47 is driven and controlled by a control unit CU, which will be described later, to control the gear ratio of the continuously variable transmission 40. On the other hand, in the vehicle, a throttle opening sensor 51 configured by a rotary potentiometer or the like for detecting a throttle opening TVO of the engine 10 and an output shaft 28 connected to an output disk 43 of the toroidal continuously variable transmission 40 are provided. Vehicle speed sensor 52 for detecting vehicle speed V _SP from rotation speed, continuously variable transmission 40
Tilt angle sensor 53 consists of detecting the tilt angle phi _D of the trunnion 45A showing a gear ratio for example, a photo inter Plata 53b against this and slit disk 53a of
A displacement sensor 54 that detects the axial displacement of the trunnion 45A by the displacement L _D of the actuator 54a that moves integrally with the trunnion 45A, the rotary shaft 13 connected to the input side of the forward / reverse switching mechanism 15. grade sensor 56 for detecting the inclination angle θ of the vehicle body front-rear direction is provided from the rotational speed as the gradient state of input the input rotation speed sensor 55 for detecting the rotational speed N _i, and the traveling path of the continuously variable transmission 40 of ing.

Among them, the gradient sensor 56 for detecting the inclination angle θ of the traveling road is, for example, the above-mentioned Japanese Patent Laid-Open No. 1-148630.
What is described in the gazette is applied. The details will be referred to the publication, and only the principle will be briefly described. For example, a vehicle speed change rate α _V obtained by differentiating the vehicle speed V _SP with time and a component force g of a gravitational acceleration parallel to a traveling path.・ Si
The sum of nθ (g: gravitational acceleration, θ: inclination of the road) is the acceleration α _S actually acting on the vehicle.
The output obtained by solving this equation of motion for the inclination angle θ can be obtained. Here, the inclination angle θ
Is output as a positive value and the inclination angle θ at the down slope is output as a negative value. Of course, it is also possible to perform the above-mentioned arithmetic processing by a microcomputer described later.

Further, the throttle opening sensor 51 is
The throttle opening of the engine is detected as a voltage signal, and the depression amount of the accelerator pedal is divided into eight stages, and the depression amount of the accelerator pedal is "0", that is, the throttle opening equivalent to it. When the fully closed state is (1/8), the accelerator pedal depression amount is the maximum, that is, when the throttle opening equivalent to that is the fully opened state is (8/8), the throttle opening is set. An analog signal corresponding to is output.

The control unit CU
As shown in FIG. 2, a microcomputer 60 that controls arithmetic processing for gear ratio control and other gear shift function control, which will be described later, and drive circuits 61L and 61R that switch and drive the electromagnetic directional control valve 47. Is equipped with. The microcomputer 60 includes an input interface circuit 60a having an A / D conversion function for reading signals from the sensors, and a microprocessor unit MPU.
An arithmetic processing unit 60b including a ROM, an RA
A storage device 60c having M or the like and an output interface opening 60d having a D / A conversion function or the like are provided and are connected to each other through a communication bus. Then, in this microcomputer 60, for example, in accordance with a calculation process for gear ratio control of FIG. 3 which will be described later, a normal target based on the throttle opening TVO from the throttle opening sensor 51 and the vehicle speed V _SP from the vehicle speed sensor 52. The input rotation speed N _imap is calculated and set, and the inclination angle θ from the gradient sensor 56 is set.
The minimum target input speed N _imin is calculated and set based on the above, and the gear ratio C to be achieved by the toroidal type continuously variable transmission 40 is calculated and set based on these, and it is necessary to achieve the gear ratio C. It outputs control signals CS _US and CS _DS .

The drive circuits 61L and 61R are
The upshift control signal CS _US and the downshift control signal CS output from the microcomputer 60.
_DS is a solenoid SL of the electromagnetic directional control valve 47,
It is converted into a drive signal to SR and output. Next, main arithmetic processing for gear ratio control executed by the arithmetic processing unit 60b of the microcomputer 60 will be described with reference to the flowchart of FIG. This calculation process is
For example, it is executed by a timer interrupt every predetermined sampling time ΔT of about 10 msec. It should be noted that although no particular steps are provided for communication in this flowchart, the maps, programs, predetermined arithmetic expressions, etc., required for arithmetic processing are read from the ROM of the storage device 60c at any time and are obtained by arithmetic operations. The calculated value and each information value are stored in the RAM of the storage device 60c as needed.

In this calculation process, first, at step S1, the throttle opening TV from the throttle opening sensor 51 is detected.
O and the vehicle speed V _SP from the vehicle speed sensor 52 are read. Next, in step S2, the target input speed TN _i is calculated and set according to the minor program of FIG. 4 described later. Next, the process proceeds to step S3, and the vehicle speed V obtained by converting the rotation speed of the output shaft 28 read in step S1.
_SP is divided by the speed reduction ratio on the output side from the output shaft 28 to calculate the rotation speed of the output shaft 28 as the output rotation speed _No.

Next, in step S4, the target input speed TN _i set in step S2 is divided by the output speed N _o calculated in step S3 to achieve the continuously variable transmission 40. The gear ratio C to be calculated is calculated. Next, in step S5, the target tilt angle φ _T of the trunnions 45A and 45B is calculated according to the gear ratio C calculated in step S4.

Next, in step S6, the trunnions 45A and 4 detected by the tilt angle sensor 53 are detected.
Read the actual current tilt angle φ _D of 5B. Next, in step S7, the target tilt angle φ _T and the current tilt angle φ _D
From the tilt angle deviation Δφ (= φ _T −φ _D ) with the trunnion 4
An axial target displacement amount L _T of 5A and 45B is calculated.

Next, in step S8, the trunnions 45A and 45B detected by the displacement sensor 54 are detected.
The current displacement amount L _D in the axial direction of is read. Next, in step S9, the target displacement amount L _T and the current displacement amount L _D
Displacement deviation between ε (= L _T -L _D) is calculated. Next, in step S10, it is determined whether the displacement amount deviation ε calculated in step S9 is a positive value, “0”, or a negative value, and the displacement amount deviation ε is a positive value. If the displacement deviation ε is “0”, the procedure proceeds to step S12, and if the displacement deviation ε is a negative value, the procedure proceeds to step S13.

In step S11, the upshift control signal CS _US is set to the logical value "1" and the downshift control signal CS _DS is set to the logical value "0", and then the process proceeds to step S14. Further, in step S12,
After setting both the upshift control signal CS _US and the downshift control signal CS _DS to the logical value "0", the process proceeds to step S14.

In step S13, the upshift control signal CS _US is set to the logical value "0" and the downshift control signal CS _DS is set to the logical value "1", and then the process proceeds to step S14. In step S14, the set upshift control signal CS _US is output to the drive circuit 61L, and the downshift control signal CS _DS is output to the drive circuit 61R, and then the timer interrupt process is ended to complete a predetermined main program. Return to.

Next, the minor program executed in step S2 of the arithmetic processing of FIG. 3 will be described with reference to the flowchart of FIG. In this minor program, the inclination angle θ from the gradient sensor 56 is first read in step S21. Next, the routine proceeds to step S22, where the throttle opening TVO and the vehicle speed V _SP read in step S1 of the arithmetic processing of FIG. 3 are used as parameters, respectively, and the normal target input from the control map of FIG. Search and set the rotation speed N _imap .

Next, in step S23, the vehicle speed V _SP read in step S1 of the arithmetic processing of FIG. 3 and the absolute value of the inclination angle | θ | read in step S21.
, _{Respectively,} are used as parameters to search and set the minimum target input rotational speed N _imin from the control map of FIG. 5 described in detail later. Then, the process proceeds to step S24, and step S
Set normal target input rotational speed N _imap it is determined whether the is the minimum target input revolution speed N _imin hereinafter set in step S23 at 22, the normal target input revolution speed N _imap
Is less than or equal to the minimum target input speed N _imin , the _{process proceeds} to step S25, and otherwise, step S26.
Move to.

In step S25, the minimum target input speed N _imin is set to the target input speed TN _i to be achieved by the continuously variable transmission 40, and then the _{process proceeds} to step S3 of the calculation process of FIG. .. Further, in step S26, the normal target input speed N _{imap is set} to the continuously variable transmission 4
After setting the target input speed TN _i to be achieved at 0, the process proceeds to step S3 of the arithmetic processing of FIG.

Next, step S22 and step S2
The control map of FIG. 5 searched in 3 will be described. First, using the vehicle speed V _SP and the throttle opening TVO as parameters, the control map searched in step S22 for setting the normal target input speed _Nimap is the vehicle speed V _SP on the horizontal axis,
Normal target input speed N _imap is the vertical axis, throttle opening TV
It is equivalent to a general control map of a normal gear shift pattern with O as a parameter, and it can be considered that a straight line passing through the origin has a constant gear ratio. Then, for example, the straight line having the largest inclination in the entire region of the shift pattern represents the largest reduction ratio of the entire vehicle, that is, the maximum gear ratio C _Hi , and conversely, the straight line having the smallest inclination has the smallest reduction ratio of the entire vehicle. That is, it represents the minimum gear ratio C _LO . On the contrary,
Even if the vehicle speed is equal to V _SP , the large depression amount of the accelerator pedal, and the large throttle opening TVO as a result, means that, for example, an acceleration force is required, or the traveling load such as an uphill road or head wind resistance causes the engine to run. Since the load required for the engine is large, it is necessary to increase the rotational speed of the engine to increase its output (torque). For this reason, the throttle opening sensor 51 detects (1
/ 8) to (8/8) as a parameter, the throttle opening TVO is used as a parameter.
Figures O1~TVO8 increases, Aru usually as the target input revolution speed N _imap is set larger.

The vehicle speed V_SPIs a certain gear ratio control start threshold
In the smaller area, the range of each shift position
Regardless of the gear ratio (that is, the shift pattern), the maximum shift
Ratio C _HiFixed to. In other words, this gear ratio control start threshold
Is for controlling the creep condition that occurs in vehicles equipped with an automatic transmission.
Think of it as the upper limit.

Although not described here in detail, the so-called L
The shift pattern when the range is selected is, for example, the vehicle speed V
_The maximum gear ratio C _Hi is fixed regardless of the _SP and the throttle opening TVO, and the gear change pattern when the so-called 2 range is selected is the maximum gear ratio C _Hi and the minimum gear ratio C _Hi.
In the region between the two-range minimum gear ratio larger than _{LO, the} control curve is a time-dependent locus of the gear ratio set according to the vehicle speed V _SP and the throttle opening TVO.

Next, the absolute values of the vehicle speed V _SP and the inclination angle |
The principle and procedure of creating the control map searched in step S23 in order to set the minimum target input speed N _imin using θ | as a parameter will be described. First, FIG.
Is a so-called driving force performance curve in which the horizontal axis represents the vehicle speed V _SP and the vertical axis represents the driving force of the vehicle with the throttle opening TVO as a parameter. In addition to this, for example, the gradient sensor 56
The driving force characteristic curves required to maintain the vehicle speed V _SP at the positive inclination angle θ of the uphill road detected in step S12 are superimposed. At this time, this uphill driving force characteristic curve is not a straight line with a uniform inclination, and the inclination gradually increases as the vehicle speed V _SP increases. Not only the running load on the uphill, but also other factors such as air resistance. This is because a traveling load is added.

When the throttle opening-output side driving force characteristic curve and the roadway inclination angle-required driving force characteristic curve are superposed in this manner, a predetermined inclination angle θ is obtained as shown in FIG.
The vehicle speed V _SP corresponding to the intersection of the required driving force characteristic curve at (in this case, the inclination angle θ ₂ ) and the output side driving force characteristic curve at each throttle opening TVO is obtained as the vehicle speed equivalent to running addition. The vehicle speed V _SP and the throttle opening TVO at this time are shown in FIG. 8 as shown in FIG.
_SP -Throttle opening TVO-Target input speed N _i Plotted on the control map and connected while appropriately interpolating the plots, the minimum target input speed from the inclination angle θ and the vehicle speed V _SP shown in FIG. _Obtain a characteristic curve that sets N _imin . At this time, even when the traveling road is an uphill road and the component force of the gravitational acceleration acts on the rear side of the vehicle, the traveling road is a downhill road and the component force of the gravitational acceleration is on the front side of the vehicle. Even if it is acting, if the absolute value of the inclination angle | θ | is the same, the absolute value of the component force of the gravitational acceleration is also the same regardless of the direction of the vector. Input speed N to maintain the vehicle at the vehicle speed
_{Since imin} should be the same, in the control map of vehicle speed-traveling road inclination angle-minimum target input rotation speed in FIG. 5, the parameter can be replaced with the absolute value | θ | of the traveling road inclination angle. . That is, the minimum target input rotational speed N _imin searched by this control map is input to the continuously variable transmission 40 required to maintain the vehicle speed V _SP on the traveling road regardless of whether the vehicle travels uphill or downhill. It can be seen that the rotation speed N _{i has} the minimum value. By the way, the target input rotational speed characteristic curve in which the absolute value | θ | of the inclination angle is "0" matches the minimum speed ratio curve C _LO . Of course, when the absolute value of the inclination angle | θ | detected by the gradient sensor 56 is a perfect analog value, that is, a continuous value, for example, the discrete data displayed in FIG. , It is also possible to search or detect the corresponding minimum target input speed N _imin .

Next, the operation of the arithmetic processing for the gear ratio control of FIGS. 3 and 4 executed in this embodiment will be described. Now, the vehicle is flat and has a good straight road (inclination angle θ ≒
0), the accelerator pedal is depressed to some extent, the throttle opening TVO is at or above the digital value (2/8), and the vehicle speed V _SP is gradually increased over the speed ratio control start threshold value. _Assuming that the normal target input speed _Nimap corresponding to the current vehicle speed _VSP and the throttle opening TVO is retrieved and set in step S22 of the calculation process of FIG. 4, the inclination read in step S21 is read. Since the angle θ is “0”, the minimum target input revolution speed characteristic curve searched in step S23 matches the minimum gear ratio C _LO curve, and therefore at least the normal target input revolution speed N in step S23. Minimum target input speed N below _{imap
Since imin} will be set for search, the same step S2
From step 4 to step S26, the normal target input speed N _imap is set to the target input speed TN _i to be achieved by the continuously variable transmission 40.

At this time, for example, assuming that the throttle opening TVO does not change and only the vehicle speed V _SP increases linearly, the target input speed TN _i set to the normal target input speed N _imap is set. As shown in FIG. 5, the increasing rate gradually decreases, while the output speed N _o calculated from the vehicle speed V _SP linearly increases in step S3 of the arithmetic processing of FIG. The target gear ratio C calculated in step 1 becomes gradually smaller, and based on this gear ratio C,
Trunnions 45A and 45 calculated in step S5
The target tilt angle φ _{T of} B and the target displacement amount L _T calculated in step S7 are achieved. However, when the throttle output TVO is constant and the engine output (torque) is constant, the vehicle driving force is consumed by a traveling load such as air resistance that increases as the vehicle speed V _SP increases. Eventually, a constant speed running state is achieved with the throttle opening TVO kept constant.

In such a constant speed traveling state, the output speed N _o calculated from the vehicle speed V _{SP in} step S3 of the arithmetic processing of FIG. 3 becomes a constant value, and the vehicle speed V _SP and throttle opening degree are also changed. As long as TVO does not change, the target input speed TN _i set in the normal target input speed N _imap also becomes a constant value, so the target gear ratio C calculated in step S4 does not change and the target tilt Since the angle φ _T and the current tilt angle φ _D coincide with each other, the tilt angle deviation Δφ calculated in step S7 also becomes “0”, and accordingly, the target displacement amount L _T also becomes “0”. Since the toroidal continuously variable transmission 40 is not performing the gear shifting operation, the displacement amount detection value L _D detected by the displacement amount sensor 54 becomes “0”, and the displacement amount deviation ε calculated in the same step S9 also It becomes "0", so that the same steps S10 to S Migration to upshift control signal to the 2 CS _US and the downshift control signal CS _DS is set to the logical value "0" together, which drive circuit 61L in step S14, is output to 61R. As a result, the exciting currents of the electromagnetic solenoids SL and SR of the electromagnetic directional control valve 47 are maintained in the cutoff state, so that the electromagnetic directional control valve 4
7 maintains the normal position and trunnions 45A and 45
B is held at the neutral position in the axial direction, the current gear ratio is maintained without performing the gear shifting operation, and the constant speed traveling state is continued.

However, on this flat and good traveling road, when the accelerator pedal is depressed by increasing the depression amount from the constant speed traveling state to the accelerating state, the throttle opening TVO is correspondingly increased, so that In step S22 of the calculation process of FIG. 4, the normal target input speed N _imap searched and set with reference to the control map of FIG. 5 changes in the increasing direction, while the inclination angle θ detected by the gradient sensor 56.
Is still "0", the minimum target input speed N _imin smaller than at least the normal target input speed N _imap is retrieved and set in the same manner as described above.
26, the normal target input speed N _imap is the continuously variable transmission 40.
Is set to the target input rotation speed TN _i that should be achieved. However, before the vehicle speed V _SP is sufficiently increased, the output speed N _o calculated in step S3 of the calculation process of FIG. 3 remains small, so that the target speed ratio C calculated in step S4 is still maintained. Becomes larger, and accordingly, the target tilt angle φ of the trunnions 45A and 45B calculated in step S5 is increased.
_T decreases in the downshift direction, and in the same step S7, the deviation Δφ between this and the current tilt angle φ _D decreases in a negative value region, and accordingly, the target displacement amount L _T has a negative value. Since the current displacement amount L _{D at} that time is “0”, the displacement amount deviation ε calculated in step S9 becomes a negative value, and the process shifts from step S10 to step S13 to down. shift control signal CS _DS is set to the logical value "1", the up-shift control signal CS _US is maintained at a logic value "0". Therefore, an exciting current of a predetermined value is output from the drive circuit 61R to the electromagnetic solenoid SR on the right side of the electromagnetic directional control valve 47, whereby the electromagnetic directional control valve 47.
Is switched to the right offset position. In response to this, the working fluid pressure output from the fluid pressure pump 48 is supplied to the fluid pressure cylinders 46b and 46d, whereby the trunnions 45A and 45B and the rotational force of the input / output disks 42 and 43 cause the trunnion 45A and 45B is tilted to the deceleration side, and the downshift is controlled so that the gear ratio matches the target gear ratio C.

When the current tilt angle φ _D detected by the tilt angle sensor 53 matches the target tilt angle φ _T , the deviation Δφ becomes “0”, and the target displacement amount L _T is also Therefore, in the arithmetic processing of FIG. 3, the process shifts from step S10 to step S12, and both the upshift control signal CS _US and the downshift control signal CS _DS are set to the logical value “0”. According to the drive circuit 61
By stopping the output of the exciting current from L and 61R, the electromagnetic directional control valve 47 returns to the normal position,
The supply of working fluid pressure to the fluid pressure cylinders 46b and 46d is stopped. However, in this state, since the internal pressures of the fluid pressure cylinders 46b and 46d are maintained in a high state, the trunnions 45A and 45B maintain the state displaced from the neutral position.
A and 45B will further tilt toward the deceleration side.

In this state, the current tilt angle φ _D becomes a large value with respect to the target tilt angle φ _T , the deviation Δφ becomes a positive value, and accordingly, the target displacement amount L _T becomes a positive value. Therefore, in the calculation process of FIG. 3, step S1
From 0 to step S11, the upshift control signal CS _US is set to the logical value "1" and the downshift control signal CS _DS is maintained to the logical value "0". Therefore, the electromagnetic solenoid SL on the left side of the electromagnetic directional control valve 47 is energized, the electromagnetic directional control valve 47 is switched to the left offset position, and the internal pressures of the fluid pressure cylinders 46b and 46d are reduced. Instead of, the internal pressure of the other fluid pressure cylinders 46a and 46c rises, whereby the trunnions 45A and 45B immediately move to the neutral position and are slightly displaced to the speed increasing side by the amount corresponding to the displacement deviation ε. As a result, the trunnions 45A and 45B slightly tilt toward the speed-increasing side, and eventually, when the current tilt angle φ _D and the target tilt angle φ _T match, the trunnions 45A and 45B.
Is returned to the neutral position and the gear shifting operation ends.

On the contrary, on the same flat and good running road,
When the accelerator pedal is released to depress the brake pedal or the like from the constant speed running state, the throttle opening TVO is correspondingly reduced, and at least the digital value (1 /
8), the normal target input speed N _imap retrieved and set with reference to the control map of FIG. 5 in step S22 of the arithmetic processing of FIG. 4 satisfies the minimum gear ratio C _LO at a minimum. On the other hand, since the inclination angle θ detected by the gradient sensor 56 is still “0”, the minimum target input speed N _{imin that} is at least smaller than the normal target input speed N _imap is the same as above. Since the search is set, the normal target input speed N is finally set in step S26.
Target input speed TN that _imap should achieve with continuously variable transmission 40
Set to _i . However, since the output speed N _o calculated in step S3 of the arithmetic processing of FIG. 3 is still large before the vehicle speed V _SP is sufficiently reduced, the target gear ratio C calculated in step S4 becomes small, Along with this, the target tilt angle φ _T of the trunnions 45A and 45B calculated in step S5 increases in the upshift direction, and in step S7, the deviation Δφ between this and the current tilt angle φ _D. Is increased in the positive value region, and the target displacement amount L _T is increased in the positive value region accordingly, and the current displacement amount L _{D at} that time
Is 0, the displacement amount deviation ε calculated in step S9 becomes a positive value, and the process proceeds from step S10 to step S11 to set the upshift control signal CS _US to the logical value “1”. , The downshift control signal CS _DS is maintained at the logical value "0". Therefore, an exciting current of a predetermined value is output from the drive circuit 61L to the left electromagnetic solenoid SL of the electromagnetic directional control valve 47, whereby the electromagnetic directional control valve 47 is switched to the left offset position. In response to this, the working fluid pressure output from the fluid pressure pump 48 is supplied to the fluid pressure cylinders 46a and 46c, so that the trunnions 45A and 45B and the input / output disk 4 are provided.
The trunnions 45A and 45B are tilted to the speed increasing side by the rotational force of 2 and 43, and the upshift gear shift control is performed so that the gear ratio matches the target gear ratio C.

Unless a decelerating operation such as depressing the brake pedal is performed, the gear ratio C of the continuously variable transmission 40 eventually becomes constant at the minimum gear ratio C _LO as the accelerator pedal is released. The rotation speed of the engine 10 decreases to the minimum rotation speed that can be _achieved at the vehicle speed V _SP , and at the same time, the output (torque) also decreases. Therefore, it is not possible to obtain a great braking force, but with appropriate engine braking force. Smooth, good coasting and so-called coasting are realized. Further, at this time, when a deceleration operation is performed clearly by depressing the brake pedal or the like, the gear ratio C of the continuously variable transmission 40 once becomes the minimum gear ratio C _LO , but the vehicle speed V _SP becomes a certain vehicle speed. When the vehicle is decelerated to below, as shown by the minimum throttle opening TVO1 curve in the control map of FIG. 5, the gear ratio C gradually increases toward the gear ratio control start threshold even if the target input speed TN _i is constant. Therefore, the constant output (torque) of the engine 10 effectively acts as back torque against the torque at which the road surface tries to rotate the drive wheels, thereby enhancing the deceleration effect during low-speed traveling. it can.

On the other hand, when the above-mentioned flat road is changed to the straight uphill road, the inclination angle θ read in step S21 of the arithmetic processing of FIG. The normal target input speed N _imap corresponding to the vehicle speed V _SP and the throttle opening TVO is retrieved and set. In step S23, the absolute value of the inclination angle | θ | (in this case | θ | = θ) And the minimum target input speed N _imin larger than the minimum speed ratio C _LO according to the vehicle speed V _SP.
Is set for search. At this time, the driver can recognize that the road is an uphill straight road, so if the accelerator pedal is depressed a lot and the throttle opening TVO is sufficiently large, the normal target input rotational speed N _imap is about the minimum target. Since it is larger than the input rotation speed N _imin , the same step S24
To step S26, the normal target input speed N _imap is the target input speed T that should be achieved by the continuously variable transmission 40.
Set to N _i . Therefore, in the calculation process of FIG. 3, the gear ratio C increases as in the downshift gear change control, resulting in an increase in the engine speed of the engine 10 and an increase in its output (torque). It becomes possible to travel on the uphill road with a sufficient acceleration force against the component force of the gravitational acceleration acting on the rear side of the vehicle.

If the accelerator pedal is released, for example, by depressing the brake pedal before reaching the uphill curved road from this uphill straight road, the normal target input rotation searched and set in step S22 of the arithmetic processing of FIG. The number N _imap is
Although minimum decreases to a value that satisfies the minimum speed ratio C _LO, the minimum target input rotational speed greater than the value that satisfies at least the minimum speed ratio C _LO because the inclination angle in the step S23 theta is not changed N _imin is set for search. At this time, if it is assumed that a sufficient time has passed since the driver released the accelerator pedal, at least the minimum target input speed N _imin is larger than the normal target input speed N _imap. In step S25, the minimum target input speed N _imin is set to the target input speed TN _i to be achieved by the continuously variable transmission 40. Therefore, in the calculation process of FIG. 3, immediately after the accelerator pedal is released, at least until the normal target input rotational speed N _imap becomes equal to or less than the minimum target input rotational speed N _imin , the gear ratio is the same as in the upshift gear shift control. Although C becomes smaller, after the normal target input speed N _imap becomes equal to or less than the minimum target input speed N _imin , the gear ratio C that is at least larger than the minimum gear ratio C _LO is maintained, and as a result, the throttle valve Although the engine is closed, the rotation speed of the engine 10 becomes high, an unnecessary reduction in the engine rotation speed is suppressed, and a large engine braking force acts to enhance the deceleration effect before the curved road.

After passing through this uphill curved road, the uphill straight line again
Depress the accelerator pedal again to move to the road.
As a result, as a result, search is performed in step S22 of the arithmetic processing of FIG.
Normal target input speed N set_imapBut the same step S
Minimum target input rotational speed N searched and set in 23_iminGreater than
When it becomes difficult, move from step S24 to step S26.
The normal target input speed N_imapIs a continuously variable transmission 40
Input speed TN to be achieved in_iSet to the above figure
In the calculation process of 3, the same as in the downshift transmission control
The gear ratio C increases. At this time, the accelerator pedal
Normal target input speed N immediately after stepping on_imapIs the minimum goal
Input speed N_iminUntil the engine 10 is exceeded
The rotation speed will not change, but at this time the engine
A rotation speed of 10 is sufficient to maintain the acceleration force on the slope.
Since the rotation speed is maintained to obtain a sufficient output,
The positive output due to the opening of the rottle valve is
Must not be consumed to increase engine speed
The normal target input speed N _imapIs the minimum target input speed N
_iminAfter this, the speed of the engine 10 is high.
The output (torque) increases as
It resists the component of gravitational acceleration acting on the rear of the vehicle on an uphill road.
It is possible to drive uphill again with sufficient acceleration.
And the engine speed will increase unnecessarily during this period.
It is also advantageous in terms of sound vibration by suppressing the decrease.

Further, a driver who is familiar with driving a vehicle equipped with a manual transmission, for example, by depressing a brake pedal after shifting from the flat straight road to the downhill straight road, has engine braking force at the gear ratio. If you release the accelerator pedal to request, like the above-mentioned uphill bend,
The normal target input rotational speed N _imap retrieved and set in step S22 of the calculation processing of FIG. 4 decreases to a value that satisfies the minimum gear ratio C _LO at the minimum, but in step S23, the absolute value of the inclination angle is reduced. Since | θ | becomes a positive value, a minimum target input rotational speed N _imin larger than a value satisfying at least the minimum speed ratio C _LO is retrieved and set. At this time, if it is assumed that a sufficient time has passed since the driver released the accelerator pedal, at least the minimum target input speed N _imin is larger than the normal target input speed N _imap. In step S25, the minimum target input speed N _imin is set to the target input speed TN _i to be achieved by the continuously variable transmission 40, and in the calculation process of FIG. Until the input rotation speed N _imap becomes equal to or less than the minimum target input rotation speed N _imin , the gear ratio C is reduced and the rotation speed of the engine 10 is reduced as in the upshift gear shift control. The input speed N _imap is the minimum target input speed N _imin
After that, the gear ratio C that is at least larger than the minimum gear ratio C _LO is maintained, and as a result, the throttle valve is closed but the rotational speed of the engine 10 is high. At this time, the engine speed of the engine 10 is large in front of the curved road due to a large engine braking force in order to generate sufficient back torque to satisfy the vehicle speed on the downhill slope of the downhill road as described above. The deceleration effect in the is increased.

[0060] From the above, prior Symbol throttle opening degree sensor 51
And step S1 of the calculation process of FIG. 3 constitutes the throttle opening detection means of the control device for the continuously variable transmission according to the present invention. Similarly, the vehicle speed sensor 52 and step S1 of the calculation process of FIG. Means for configuring the gradient sensor 56
And step S21 of the arithmetic processing of FIG. 4 constitutes the gradient state amount detecting means, and steps S23 to S23 of the arithmetic processing of FIG.
Step S26 constitutes the target input speed control means, the entire arithmetic processing of FIG. 4 constitutes the target input speed limiting means, and the arithmetic processing of FIG. 3 including the arithmetic processing of FIG. 4 and FIG.
The control unit CU shown in (1) constitutes the gear ratio control means.

Next, a second embodiment of the control apparatus for the continuously variable transmission according to the present invention will be described. The basic vehicle structure of this embodiment is the same as or substantially the same as that of the first embodiment shown in FIG. 2, so a detailed description thereof will be omitted. Further, the configuration and operation of each sensor provided in the vehicle and the continuously variable transmission are the same as or substantially the same as those of the first embodiment, and therefore detailed description thereof will be omitted. Also, the configuration of the control unit that controls the gear ratio of the continuously variable transmission is the same as or substantially the same as that of the first embodiment except for a part of the arithmetic processing to be described later, so a detailed description thereof will be given. Omit it. Further, the main arithmetic processing for gear ratio control executed by the arithmetic processing unit of the microcomputer in the control unit is similar to or substantially the same as that of the first embodiment shown in the flowchart of FIG. Therefore, detailed description thereof will be omitted.

Next, the minor program of this embodiment executed in step S2 of the arithmetic processing of FIG. 3 will be described with reference to the flowchart of FIG. In this minor program, first, in step S121, the gradient sensor 5
The inclination angle θ from 6 is read. Next, in step S122, the minimum throttle opening TVO _min corresponding to the absolute value | θ | of the tilt angle read in step S21 is calculated according to the following equation (1).

TVO _min = k · sin | θ | (1) where k is a preset proportional coefficient. Next, the routine proceeds to step S123, where the minimum throttle opening TVO _min calculated and set at step S122 is set to the value shown in FIG.
To determine whether it is less than the throttle opening TVO read in step S1 of calculation process, when the minimum throttle opening TVO _min is equal to or less than the throttle opening TVO, the process proceeds to step S124, the otherwise In that case, the process proceeds to step S125.

In step S124, the read throttle opening TVO is set as the map search throttle opening TVO _map , and then the process proceeds to step S126. In step S125, the calculated minimum throttle opening TVO _min is set in the map search throttle opening TVO _map , and then in step S1.
Move to 26.

In step S126, the map search throttle opening TVO _map and step S1 in FIG.
Using the vehicle speed V _SP read in
After the target input speed TN _i is retrieved and set from the control map of FIG. 5, the process proceeds to step S3 of the arithmetic processing of FIG. Next, regarding the control map of FIG. 5 searched in step S126, it is basically the same as the description in the first embodiment, and the throttle opening TVO as a parameter is the throttle opening for map search. Degree TVO _map
Is changed to the target input rotation speed N _imap to be achieved by the continuously variable transmission 40.
Since it is only changed to N _i , its detailed description is omitted. Therefore, in the arithmetic processing of FIG. 3, with respect to the target input rotation speed TN _i set in this control map search,
The gear ratio control is directly performed.

Next, the principle of calculating the minimum throttle opening TVO _min calculated in step S122 and the procedure for setting the proportional coefficient k will be described. The absolute value of the inclination angle of a certain traveling path as mentioned above | theta | in, the vehicle speed V _SP
As shown in FIG. 7, the driving force of the vehicle, that is, the output (torque) of the engine required to maintain the above is represented by a curve that rises to the right as the vehicle speed V _SP increases. Further, the positive vehicle driving force, that is, the engine output (torque), is represented by a curve that is approximately downward-sloping as the throttle opening TVO increases, as shown in FIG. Therefore, when the target input speed to be achieved by the continuously variable transmission is searched and set in the control map of vehicle speed-throttle opening-target input speed of FIG. 5, the driving force characteristic curve shown in FIG. If the throttle opening, which is a parameter, is regulated so that the throttle opening is at the intersection with the uphill road driving force characteristic curve, the target input speed that achieves the driving force searched and set at that throttle opening, that is, The gear ratio of the stepped transmission is a target input speed and gear ratio sufficient to maintain the vehicle speed V _SP on the uphill road, and as described above, this principle is applied to the downhill road as well. ,
If the regulation value of the throttle opening is set according to the absolute value | θ | of the inclination angle of the downhill road, the target input speed and the gear ratio are sufficient to maintain the vehicle speed V _SP on the downhill road. become.

Therefore, it acts on the vehicle as an acceleration / deceleration force.
Is the component of gravitational acceleration parallel to the road,
 Since sin | θ |, the uphill road driving force curve shown in FIG.
The proportionality coefficient k is set so that the line can be linearly approximated, and
Minimum throttle opening TVO calculated based on Equation 1
_minIf the throttle opening TVO is regulated by
In the control map of vehicle speed-throttle opening-target input speed
Target input speed TN set by search_iBut directly
Vehicle speed V on uphill or downhill_SPTarget input rotation to maintain
It will be the minimum number. Where the actual uphill drive
The power characteristic curve is the vehicle speed V as described above._SPLarge with increasing
The vehicle speed V _SPWill increase
However, the slope becomes larger, and it is
I will ignore the influence of resistance, but in that way
However, it is known that there is not much influence. However, the book
In the embodiment, the throttle opening TVO is set to (1
/ 8) to (8/8) digital value is detected
Then, this and the minimum throttle opening T calculated by the above equation 1
VO_minThe proportional coefficient k is set so that
It goes without saying that we have to decide.

Next, as shown in FIG. 3 and FIG.
The operation of the calculation process for the gear ratio control of FIG. 9 will be described.
To do. Here, the vehicle runs on a good flat road (inclination angle θ ≈ 0)
If it is, the step S of the arithmetic processing of FIG. 9 is performed.
Minimum throttle opening TVO calculated in 122_minBut
It becomes "0", and in any case, the same step S123
From step S124 to the detected throttle
The opening TVO is the throttle opening TVO for map search _mapTo
Since it is set, the search setting is substantially performed in step S126.
Target input speed T to be achieved by the continuously variable transmission 40 that is set
N_iIs the traffic that is set when traveling on a flat road in the first embodiment.
Normal target input speed N_imapSince it is the same as
Detailed explanation is omitted, including the shifting operation of the continuously variable transmission.
To do.

On the other hand, if the accelerator pedal is released before shifting from the above-described flat road to the straight road uphill and before reaching the curved road uphill, step S122 of the calculation process of FIG.
Since the minimum throttle opening TVO _min calculated and set at is a certain positive value according to the sine value of the absolute value | θ | of the inclination angle of the uphill road, the detected throttle opening TVO _min
Becomes smaller than the minimum throttle opening TVO _min , the process proceeds from step S123 to step S125, and the minimum throttle opening TVO _min is set to the _map search throttle opening TVO _map.
In 6, the target input rotation speed TN _i to be achieved by the continuously variable transmission 40 is set to a target input rotation speed larger than at least a value satisfying the minimum speed ratio C _LO by using this map search throttle opening TVO _map. Is set. Therefore, in FIG.
In the calculation process, the gear ratio C becomes small just after the accelerator pedal is released and at least until the detected throttle opening TVO becomes smaller than the minimum throttle opening TVO _min , as in the upshift transmission control. ,
After the detected throttle opening TVO becomes smaller than the minimum throttle opening TVO _min , the gear ratio C larger than at least the minimum gear ratio C _LO is maintained, and as a result, the throttle valve is closed, but the engine is closed. The rotation speed of 10 becomes high, and unnecessary reduction of the engine rotation speed is suppressed, and a large engine braking force acts to enhance the deceleration effect before the curved road.

If there is no regulation of the minimum value of the throttle opening TVO, the target input speed TN _i retrieved and set in step S126 of the calculation process of FIG. 9 is:
The minimum gear ratio C _LO is reduced to a value that satisfies the minimum, and as a result, the continuously variable transmission 40 achieves the minimum gear ratio C _{LO and} the rotational speed of the engine 10 is greatly reduced, and at the same time, engine braking is performed. The force becomes smaller and the deceleration effect in front of the curved road becomes smaller.

On the other hand, when the accelerator pedal is stepped on again after passing through the uphill curved road, the minimum throttle opening TVO calculated and set in step S122 of the calculation processing of FIG. 9 is set.
_{Since min} is smaller than the detected throttle opening TVO, the target input speed equivalent to the normal target input speed N _{imap of} the first embodiment is the target input to be achieved by the continuously variable transmission 40 in step S126. Is set to the rotation speed TN _i ,
In the calculation process of FIG. 3, the gear ratio C increases as in the downshift gear shift control. At this time, the rotational speed of the engine 10 does not change immediately after the accelerator pedal is depressed until the throttle opening TVO exceeds the minimum throttle opening TVO _min. Since the engine speed is maintained at a speed sufficient to maintain the acceleration force on the uphill road, the positive output due to the opening of the throttle valve is consumed to increase the engine speed. After that, after that, the rotation speed of the engine 10 rapidly increases and its output (torque) increases, and a sufficient acceleration force is exerted against the component force of the gravitational acceleration acting to the rear of the vehicle on the uphill road. It becomes possible to drive on the uphill road again.

Further, when the accelerator pedal is released on the downhill straight road, the minimum throttle opening TV calculated from the absolute value of the inclination angle | θ | is calculated in step S122 of the calculation process of FIG.
Since O _{mi n} is certain positive value, the minimum throttle opening TVO _min is larger than the detection throttle opening TVO which satisfies at least the minimum speed ratio C _LO, the step S
In step S125, the minimum throttle opening TVO _min is changed to the map search throttle opening TV.
Is set to O _MAP, in the step S126, the target input revolution speed TN _i to be achieved by the continuously variable transmission 40 is calculated and set according to the map search throttle opening TVO _MAP. Therefore, in the calculation process of FIG. 3, the throttle opening TV detected at least immediately after the accelerator pedal is released.
Until O becomes larger than the minimum throttle opening TVO _min , the gear ratio C is the same as in the upshift gear shift control.
Becomes smaller and the rotation speed of the engine 10 also decreases, but the detected throttle opening TVO is the minimum throttle opening T0.
After becoming larger than VO _min , the gear ratio C that is at least larger than the minimum gear ratio C _LO is maintained, and as a result, the throttle valve is closed but the rotation speed of the engine 10 becomes high. At this time, the engine speed of the engine 10 is large in front of the curved road due to a large engine braking force in order to generate sufficient back torque to satisfy the vehicle speed on the downhill slope of the downhill road as described above. The deceleration effect in the is increased.

As described above, in the control apparatus for the continuously variable transmission of this embodiment, it is necessary to maintain the vehicle speed against the inclination angle of the traveling road, that is, the component force of the gravitational acceleration acting parallel to the traveling road. By controlling the throttle opening for searching or setting the target input speed to be achieved in the continuously variable transmission with the minimum throttle opening approximated to the throttle opening, the same effect as the first embodiment can be obtained. In addition to the above, it is possible to reduce the stockpiling amount of data in the arithmetic processing because, for example, it is not necessary to have a control map composed of the road driving force characteristic curve in this way. There is an advantage that the calculation load can be reduced.

[0074] From the above, prior Symbol throttle opening degree sensor 51
And step S1 of the calculation process of FIG. 3 constitutes the throttle opening detection means of the control device for the continuously variable transmission according to the present invention. Similarly, the vehicle speed sensor 52 and step S1 of the calculation process of FIG. Means for configuring the gradient sensor 56
9 and step S121 of the arithmetic processing of FIG. 9 constitutes a gradient state amount detecting means, and step S12 of the arithmetic processing of FIG.
2 to step S125 constitute throttle opening regulating means, the entire arithmetic processing of FIG. 9 constitutes target input speed limiting means, and the arithmetic processing of FIG. 3 including the arithmetic processing of FIG. 9 and FIG. The control unit CU constitutes the gear ratio control means.

Next, a third embodiment of the control apparatus for a continuously variable transmission according to the present invention will be described. The basic vehicle structure of this embodiment is the same as or substantially the same as that of the first embodiment shown in FIG. 2, so a detailed description thereof will be omitted. Further, the configuration and operation of each sensor provided in the vehicle and the continuously variable transmission are the same as or substantially the same as those of the first embodiment, and therefore detailed description thereof will be omitted. Also, the configuration of the control unit that controls the gear ratio of the continuously variable transmission is the same as or substantially the same as that of the first embodiment except for a part of the arithmetic processing to be described later, so a detailed description thereof will be given. Omit it. Further, the main arithmetic processing for gear ratio control executed by the arithmetic processing unit of the microcomputer in the control unit is similar to or substantially the same as that of the first embodiment shown in the flowchart of FIG. Therefore, detailed description thereof will be omitted.

Next, the minor program of this embodiment executed in step S2 of the arithmetic processing of FIG. 3 will be described with reference to FIG.
This will be described with reference to the flowchart of. However, steps S22 to S26 of this minor program are exactly the same as the steps of the minor program shown in FIG. 4 of the first embodiment, and step S21 is replaced with step S21 ', and after step S26. Since only steps S27 to S31 are added, only different steps will be described here.

In this minor program, first, in step S21 ′, the inclination angle θ from the gradient sensor 56 and the current input rotational speed N _i from the input rotational speed sensor 55 are read.
Further, without returning to the main program directly from step S25 or step S26, the process proceeds to step S27, and the target input speed TN _i set in step S25 or step S26 is read at step S21 '. It is determined whether the input rotation speed N _{i is} larger than
If the target input rotation speed TN _i is larger than the current input rotation speed N _{i, the process} proceeds to step S28, and if not, the process proceeds to step S3 of the arithmetic processing of FIG.

In step S28, it is determined whether or not the throttle opening TVO is larger than a preset relatively large predetermined value A, and if the throttle opening TVO is larger than the predetermined value A, step S29. Moved to
If not, the process proceeds to step S30. In step S30, it is determined whether or not the throttle opening TVO is smaller than a preset relatively small predetermined value B. If the throttle opening TVO is less than the predetermined value B, the process proceeds to step S31. If not, the process proceeds to step S3 of the arithmetic processing shown in FIG.

In step S31, it is determined whether or not the differential value of the vehicle speed, that is, the vehicle acceleration _V'SP is greater than "0" and the differential value thereof, the vehicle acceleration change rate V " _SP, is" 0 ". It is determined whether or not the acceleration is constant. If the acceleration is constant, the process proceeds to step S3 of the arithmetic processing of FIG. 3, and if not, the process proceeds to step S29.

In the step S29, the step S
After setting the input rotation speed N _i read at 21 'to the target input rotation speed TN _i to be achieved by the continuously variable transmission 40, the process proceeds to step S3 of the calculation process of FIG. Next, the operation of the arithmetic processing for the gear ratio control of FIGS. 3 and 9 executed in this embodiment will be described.

Here, on a good road where the vehicle is flat (inclination angle θ≈
When the vehicle is traveling in 0), the same processing as that of the first embodiment is performed, and thus detailed description thereof will be omitted.
The basic operation when the target input speed TN _i set up to step S26 on the uphill road or the downhill road is equal to or lower than the current input speed N _i is also the same as that of the first embodiment. Therefore, the detailed description thereof will be omitted and only the operation under different circumstances will be described in detail.

On the other hand, for example, while traveling on an uphill road as described above, the positive inclination angle θ of the uphill road becomes large, and as a result, the target input rotational speed T regulated in step S25 is reached.
When N _i becomes larger than the current input rotational speed N _i and the driver accordingly depresses the accelerator pedal largely to the extent that the throttle opening TVO exceeds the comparatively large predetermined value A, further down. When the gear ratio control in the shift direction is executed, the engine speed greatly increases, which causes a feeling of strangeness. Therefore, in the arithmetic processing of FIG. 10, the steps S27 to S28 are followed by the step S27.
29, the target input speed TN _i is set to the current input speed N _i . Therefore, in the calculation process of FIG. 3, the current gear ratio C and the current input rotation speed _Ni are maintained, and a large increase in the engine rotation speed is prevented. In addition, in order to obtain further acceleration force from such a depressed state of the accelerator pedal, the driver once depresses the accelerator pedal in anticipation of a downshift, and then immediately depresses the accelerator pedal, and the throttle at that time is depressed. The opening TVO is the predetermined value A
By the time or less, because until the rotational speed of the engine in the current that has been maintained input rotational speed N _i which it is exhibits still sufficient output (torque) of the engine by the gear ratio control to subsequent downshift direction The number of rotations increases rapidly, its output increases, and the acceleration of the vehicle increases.

When the accelerator pedal is released during traveling on a downhill and the throttle opening TVO is smaller than the relatively small predetermined value B, the absolute value of the negative inclination angle | θ | As a result, the above step S2
When the target input speed TN _i regulated by 5 becomes larger than the current input speed N _i , the gear ratio control in the downshift direction is executed as it is, and the driver does not step on the accelerator pedal. The input rotation speed N _i , that is, the rotation speed of the engine increases, and the occupant feels uncomfortable. Therefore, in the calculation process of FIG. 10, in such a case, the process proceeds from step S27 to step S28, and then from step S30 to step S31. If the downward gradient acceleration is not constant, the process proceeds to step S29. Thus, the target input speed TN _i is set to the current input speed N _i . Therefore, in the calculation process of FIG. 3, the current gear ratio C and the current input rotational speed N _i are maintained, and the uncomfortable feeling that the engine rotational speed increases even when the driver does not press the accelerator pedal is avoided.

[0084] On the other hand, when the an acceleration due to the down slope is constant in the step S31, since the current input rotational speed N _i is greater than the target input revolution speed TN _i is set as it is, the downshift is the arithmetic processing of Fig. 3 The gear ratio control in the direction is executed. For example, when a driver approaches a downhill road, releases the accelerator pedal, the vehicle speed temporarily decreases, and then the vehicle speed accelerates again due to the downward slope, the engine is downshifted under a constant acceleration condition due to the downward slope. Since it is expected that the braking force will increase, it is possible to obtain the desired engine braking force by executing the downshift at the timing desired by the driver in the arithmetic processing of FIGS. 10 and 3.

As described above, in the control apparatus for the continuously variable transmission according to the present embodiment, in addition to the effects of the first embodiment, the timing of downshift, that is, the timing of increase of the engine speed is set to the vehicle running condition or the accelerator. Since the control can be appropriately performed according to the stepped-on state of the pedal, it is possible to suppress an unnecessary increase and decrease in the engine speed and avoid or suppress an uncomfortable feeling for the occupant.

[0086] From the above, prior Symbol throttle opening degree sensor 51
And step S1 of the calculation process of FIG. 3 constitutes the throttle opening detection means of the control device for the continuously variable transmission according to the present invention. Similarly, the vehicle speed sensor 52 and step S1 of the calculation process of FIG. Means for configuring the gradient sensor 56
10 and the step S21 'of the calculation process of FIG. 10 constitutes the gradient state amount detecting means, and the step S21' of the calculation process of FIG.
23 to step S26 constitute the target input speed control means, the entire arithmetic processing of FIG. 10 constitutes the target input speed limiting means, and the arithmetic processing of FIG. 3 including the arithmetic processing of FIG. 10 and FIG. The shown control unit CU constitutes the gear ratio control means.

As described above, in each of the above-described embodiments, the target rotational speed to be achieved by the continuously variable transmission is restricted so as not to be lower than the traveling load rotational speed corresponding to the absolute value of the gradient state amount detection value. As described above, the rotation speed may be limited so as not to become lower than the traveling load rotation speed by a predetermined small value set in advance. Further, although each of the above embodiments is based on a toroidal type continuously variable transmission, it goes without saying that the present invention can be widely applied to other belt type continuously variable transmissions and the like.

Further, in each of the above-mentioned embodiments, only the gear ratio control controller constructed by a microcomputer has been described in detail. However, the invention is not limited to this, and it may be configured by combining electronic circuits such as arithmetic circuits. It goes without saying that it is good.

[0089]

As described above, according to the control device for a continuously variable transmission of the present invention, by using the absolute value of the gradient state amount detection value of the traveling road, the traveling load effective on both the uphill road and the downhill road can be obtained. By setting the rotation speed, the target input rotation speed that should be achieved by the continuously variable transmission is limited so that it does not fall below this running load rotation speed, and the target continuously variable transmission of the continuously variable transmission is achieved so that this target input rotation speed is achieved. By controlling the gear ratio (vehicle speed reduction ratio), even if the accelerator pedal is repeatedly depressed and released frequently when traveling on a curved uphill road, the engine speed does not increase or decrease more than necessary. Even when the accelerator pedal is depressed from the released state,
Since the output (torque) of the engine is not significantly consumed only for increasing the engine speed, the desired driving force can be easily obtained, and when the vehicle is traveling on a downhill road, the gradient state quantity of the road is reduced. The target input speed is set high according to the absolute value of the detected value, and the gear ratio of the continuously variable transmission (vehicle speed reduction ratio) is controlled to a large speed ratio (speed reduction ratio), and the engine speed also increases. , Can obtain sufficient engine braking force. Further, by limiting the target input speed that should be achieved by the continuously variable shift so as not to be lower than the speed lower than the traveling load speed by a preset small value, the engine braking as described above is performed. It is also possible to suppress the feeling of excessive force.

The minimum input rotation of the continuously variable transmission that obtains an engine output sufficient to keep going uphill at the vehicle speed concerned and an engine braking force sufficient to keep going downhill at the vehicle speed concerned. Based on the preset minimum rotation speed correlation, the number is set to the minimum limit value of the target input rotation speed from the absolute values of the vehicle speed detection value and the gradient state amount detection value, and the minimum limit value of the target input rotation speed is By restricting the target input speed that should be achieved by the multi-speed transmission, the gear ratio of the continuously variable transmission (vehicle reduction ratio), that is, the engine speed can be adjusted according to the gradient condition of the road, the vehicle speed, and the throttle opening. It can be controlled to a suitable state.

Further, when the throttle opening detection value is equal to or greater than the predetermined value, even if the target input speed set according to the change in the slope condition of the traveling path becomes equal to or higher than the input rotation speed detection value, it is continuously variable. By limiting the target input speed that should be achieved by the transmission to a value equal to or lower than the detected input speed, the vehicle speed due to changes in the gradient state quantity of the road can be controlled even if the driver does not operate the accelerator pedal. It is possible to avoid a downshift that is executed more than the change, that is, an increase in the engine speed, and eliminate a sense of discomfort to an occupant.

When the detected throttle opening value changes in the closing direction, the target input speed that should be achieved by the continuously variable transmission is held at the input rotational speed detection value before the change of the throttle opening. It is possible to avoid a downshift that is performed even when the driver depresses the accelerator pedal, that is, an increase in the engine speed, and eliminate a feeling of discomfort to an occupant.

Further, when the detected throttle opening value changes in the opening direction, the target input rotational speed to be achieved by the continuously variable transmission is set to both the set target input rotational speed and the input rotational speed detected value. By limiting the above, it is possible to obtain a desired driving force promptly. Also,
When the throttle opening detection value is equal to or less than a predetermined value and the target input speed set according to the change in the slope condition of the roadway is equal to or higher than the input speed detection value, the vehicle acceleration detection value is equal to or higher than the predetermined value and the acceleration change occurs. The target input speed that should be achieved by the continuously variable transmission after the rate detection value becomes equal to or less than the predetermined value and the constant speed is set to the input speed detection value or more The shift can be executed to increase the engine speed and obtain an appropriate engine braking force.

Further, at the minimum limit value of the throttle opening which can obtain the output (torque) of the engine or the engine braking force necessary for traveling through the traveling path of (the absolute value of) a certain gradient state amount, the shift is performed. By restricting the throttle opening, which is a parameter for searching the correlation, the gear ratio of the continuously variable transmission (vehicle speed reduction ratio), that is, the engine speed, which is sufficient to drive the vehicle on the road at the vehicle speed, is preferable. It is possible to control such a state, and it is possible to reduce the amount of information in arithmetic processing.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a control device for a continuously variable transmission according to the present invention.

FIG. 2 is a configuration diagram showing an example of a continuously variable transmission.

FIG. 3 is a flowchart showing an example of a calculation process of a gear ratio control of a continuously variable transmission that is executed by the control unit of FIG.

4 is a flowchart showing a first embodiment of a minor program executed to obtain a target input rotation speed in the arithmetic processing of FIG.

5 is an explanatory diagram showing an example of a control map searched by the arithmetic processing of FIG.

FIG. 6 is an explanatory diagram showing an example of driving force characteristics.

FIG. 7 is an explanatory diagram showing an example of a driving force characteristic required on a slope road.

FIG. 8 is an explanatory diagram for the principle and creation of the control map of FIG.

9 is a flowchart showing a second embodiment of the minor program executed to obtain the target input rotation speed in the arithmetic processing of FIG.

10 is a flowchart showing a third embodiment of the minor program executed to obtain the target input rotation speed in the arithmetic processing of FIG.

[Explanation of symbols]

10 is an engine 12 is a fluid coupling 13 is a rotation axis 14 is a drive shaft 15 is a forward / reverse switching mechanism 20 is a gear reduction mechanism 22 is a differential device 42 is an input disk 43 is an output disc 44A and 44B are transmission rollers 45A and 45B are trunnions 46a to 46d are fluid pressure cylinders 47 is a solenoid directional valve 51 is a throttle opening sensor 52 is a vehicle speed sensor 53 is a tilt angle sensor 54 is a displacement sensor 55 is an input speed sensor 56 is a gradient sensor 60 is a microcomputer 61L and 61R are drive circuits CU is a control unit

Continuation of front page (51) Int.Cl. ⁷ Identification code FI F16H 59:66 F16H 59:66 101: 04 101: 04

Claims (6)

(57) [Claims] 1. A throttle opening detecting means for detecting an opening of a throttle valve, a vehicle speed detecting means for detecting a vehicle speed, and a target for a continuously variable transmission mounted in a vehicle with the throttle opening and the vehicle speed as variables in advance. Has a shift correlation that can set the input rotation speed, and at least from the throttle opening detection value detected by the throttle opening detection means and the vehicle speed detection value detected by the vehicle speed detection means based on the shift correlation, Set the target input speed to the continuously variable transmission,
In a control device for a continuously variable transmission equipped with a gear ratio control means for controlling a gear ratio of the continuously variable transmission so as to achieve a set target input speed, a gradient state for detecting a gradient state quantity of a traveling road. And a gear ratio control means, in which the target input speed to be achieved by the continuously variable transmission corresponds to an absolute value of the gradient state quantity detection value detected by the gradient state quantity detection means. The target input rotation speed limiting means for limiting the load rotation speed or the rotation speed lower than the rotation speed by a predetermined value lower than the rotation speed is provided .
The number limiting means uses the vehicle speed and the gradient state quantity of the road as variables.
The minimum limit value of the input speed to the continuously variable transmission is set as
Has a minimum deterministic rotation speed correlation, and
Based on the vehicle speed detection value detected by the vehicle speed detection means based on
The gradient state quantity detection value detected by the gradient state quantity detection means
Target input speed corresponding to the running load speed from the pair value
Set the minimum limit value of
Value and the target input speed set from the shift correlation
Whichever of them, whichever is smaller, should be achieved with the continuously variable transmission.
The target input speed control means to set the target input speed.
A control device for a continuously variable transmission characterized by being provided . 2. The input rotation speed detecting means for detecting an input rotation speed to the continuously variable transmission, wherein the target input rotation speed limiting means has a throttle opening detection value detected by the throttle opening detection means. When the target input rotation speed set by the target input rotation speed regulation means due to a change in the slope condition of the traveling path is equal to or more than a predetermined value and becomes equal to or more than the input rotation speed detection value detected by the input rotation speed detection means. the control device for a continuously variable transmission according to claim 1, characterized in that to limit the target input rotational speed to be achieved by the continuously variable transmission input rotation speed equal to or less than the input rotational speed detection value. 3. The target input rotation speed limiting means is a target input rotation speed to be achieved by the continuously variable transmission when the throttle opening detection value detected by the throttle opening detection means changes in the closing direction. 3. The control device for the continuously variable transmission according to claim 2 , wherein is held at the input rotation speed detection value before the change of the throttle opening detected by the input rotation speed detection means. 4. The target input rotation speed limiting means is a target input rotation speed to be achieved by the continuously variable transmission when the throttle opening detection value detected by the throttle opening detection means changes in the closing direction. The input rotation speed detection value detected by the input rotation speed detection means and the target input rotation speed set by the target input rotation speed regulating means, whichever is smaller, whichever is smaller. The control device for a continuously variable transmission according to claim 3 , wherein: 5. A vehicle acceleration detecting means for detecting an acceleration of the vehicle, and an acceleration change rate detecting means for detecting a change rate of the acceleration of the vehicle, wherein the target input rotational speed limiting means is the throttle opening detecting means. The detected throttle opening value is less than or equal to a predetermined value, and the target input speed set by the target input speed regulation means is detected by the input speed detection means due to a change in the slope condition of the road. When the input rotation speed detection value is equal to or higher than the input rotation speed detection value, the vehicle acceleration detection value detected by the vehicle acceleration detection means is a predetermined value or more and the acceleration change rate detected by the acceleration change rate detection means. Until the detected value is below the specified value,
Said target input rotational speed to be achieved by the continuously variable transmission, control device for a continuously variable transmission according to claim 1, characterized in that to limit the input rotational speed to be the input rotational speed detecting Ne以 under. 6. A slot for detecting the opening of a throttle valve.
Vehicle opening detection means and vehicle speed detection means for detecting vehicle speed
In advance, set the throttle opening and vehicle speed as variables in the vehicle.
The target input speed to the mounted continuously variable transmission can be set.
Effective shift correlation, and based on at least the shift correlation
Throttle detected by the throttle opening detection means
Opening detection value and vehicle speed detection by the vehicle speed detection means
From the value, set the target input speed to the continuously variable transmission,
The continuously variable transmission to achieve the set target input speed
Continuously variable transmission having a gear ratio control means for controlling the gear ratio of the
Detecting the slope condition quantity of the road in the machine controller
A gradient state amount detecting means, wherein the gear ratio control means is
The target input speed to be achieved by the continuously variable transmission is
Absolute value of slope state quantity detection value detected by state quantity detection means
Is equal to the running load speed or
Restricted so that it does not fall below the number of revolutions lower by the set predetermined value
Target input speed limiting means, the target input speed limiting means sets the minimum limit value of the throttle opening from the absolute value of the gradient state quantity detection value detected by the gradient state quantity detecting means. A variable of the throttle opening for setting the target input speed from the shift correlation, whichever is the smaller of the minimum limit value of the throttle opening and the throttle opening detection value detected by the throttle opening detection means. you comprising the throttle opening degree restricting means for setting the
Control device for a continuously variable transmission.