JPH05172226A - Shift control device for continuously variable transmission - Google Patents

Abstract

PURPOSE:To improve the car driving feeling when the gear ratio is to be changed, by calculating the target acceleration in accordance with the car speed and the degree of throttle opening, determing the conversion gain of the shift speed in accordance with the ratio to the actual acceleration multiplying with the deviation revolving speed, and thereby calculating the shift speed. CONSTITUTION:A continuously variable transmission 20 varies the gear ratio continuously by regulating the effective diameters of a primary and a secondary pulley 26, 28 by the cylinder of each pulley. Each cylinder is connected with a main and an aux. port of a gear ratio control valve 54, which receives the adjusting pressure from a pressure control valve and the shift speed control pressure of a solenoid-operated control valve 23 and is changed over. The solenoid-operated control valve 23 performs control with an ECU 21, and at this control, the target acceleration of the car is calculated on the basis of the car speed and the degree of throttle opening, and the conversion gain of the shift speed is calculated in accordance with the ratio to the actual acceleration. This conversion gain is multiplied with the deviation revolving speed to yield the shift speed, with which the solenoid-operated control valve 23 is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a speed change speed of a transmission which changes a winding diameter ratio of a belt wound around a pair of pulleys by switching operation of a hydraulic actuator, and more particularly, a primary speed control device. The present invention relates to a shift control device for a continuously variable transmission that calculates a shift speed based on a deviation between an actual pulley rotation speed and a target primary pulley rotation speed, and changes a winding diameter ratio of both pulleys at this shift speed to perform a continuously variable transmission.

[0002]

2. Description of the Related Art Conventionally, a belt drive type continuously variable transmission in which a drive belt is wound between a primary pulley and a secondary pulley, and the winding diameter ratio of the belts wound around both pulleys is changed to continuously change gears. It has been known. This continuously variable transmission supplies the shift control hydraulic pressure based on the gear ratio determined according to the operating information of the engine to the spool of the gear ratio control valve, and each pulley control hydraulic pressure adjusted based on the hydraulic pressure switching operation of the spool. Is supplied to both hydraulic actuators for operating the relative distance between the fixed pulley material and the movable pulley material of both the primary and secondary pulleys. With this configuration, the winding diameter ratio of the belt wound around the pair of pulleys is changed to perform continuously variable speed.

By the way, the gear ratio i of the continuously variable transmission becomes a ratio i (= Wp / Ws) between the primary pulley rotation speed Wp and the secondary pulley rotation speed Ws, and when the gear ratio i is corrected to a target value, control is performed. The means supplies, to the hydraulic actuators of both the primary and secondary pulleys, each pulley control hydraulic pressure that can achieve the target speed ratio using the speed change control valve and the electromagnetic control valve. In this case, as shown in FIG. 13, the control means controls the target primary pulley rotation speed Wpo and the actual primary pulley rotation speed Wp corresponding to the target gear ratio.
, The deviation E1 (= Wpo-Wp) is obtained,
The variation gain K1 that decreases the responsiveness as the engine speed increases and the variation gain K2 that increases the responsiveness as the deviation between the actual value of the primary pulley and the target value increase are obtained.
1 is multiplied by both gains K1 and K2 to obtain the basic shift speed Vi1.
Is calculated, the basic shift speed Vi1 is sequentially integrated to obtain an integral term ΣΔViI, which is multiplied by a limiter and multiplied by a correction coefficient 1 / Z to obtain an integrated corrected shift speed ViI. Then, the basic shift speed Vi1 and the integral correction shift speed ViI are added to calculate the shift speed Vi, and the same shift speed V
A gear ratio control valve that receives the gear shift speed control pressure Pc by driving the electromagnetic control valve with the gear shift speed signal Du corresponding to the gear shift speed control pressure Pc capable of achieving i and adjusting the gear shift speed control pressure Pc Supplies the pulley control hydraulic pressure to the hydraulic actuators of both pulleys, and switches both pulleys to the target speed ratio i.

[0004]

By the way, as described above, each map of the change gain K1 for decreasing the responsiveness and the change gain K2 for increasing the responsiveness that the control means adopts when determining the shift speed is fixed. .. For this reason, if these gains are lowered, the shift responsiveness is lowered, so that the gain is set as large as possible, and the responsiveness at the time of acceleration of the vehicle is secured. However, when the gain is increased in this way, the response of shifting (the response of shifting speed)
However, at the time of kickdown, the engine power is used only to increase the engine speed (the primary pulley speed), and the vehicle acceleration cannot be increased appropriately, resulting in a driving feeling. It cannot be improved and it becomes a problem.

An object of the present invention is to provide a shift control device for a continuously variable transmission, which has an improved driving feeling.

[0006]

In order to achieve the above-mentioned object, the present invention is mounted on a primary pulley and a secondary pulley around which a drive belt is wound, and the winding diameter ratio of the both pulleys is a predetermined gear ratio. And a pair of hydraulic actuators for increasing or decreasing each pulley clearance so as to obtain a value corresponding to the above, and a deviation rotation speed between the actual rotation speed of the primary pulley and a target primary pulley rotation speed corresponding to a designated target gear ratio is calculated. Deviation rotational speed calculation means, speed change speed calculation means for calculating a speed change speed based on the deviation speed, speed change drive means for calculating a speed change speed signal corresponding to the speed change speed and driving an electromagnetic control valve, The control valve receives the speed change control pressure generated in response to the speed change signal and adjusts the pulley control oil pressure of each of the pair of hydraulic actuators to control both pulleys to the target speed ratio. A gear ratio control valve for switching and driving, wherein the gear shift speed calculation means calculates a target acceleration of the vehicle according to the vehicle speed and a throttle opening, and a conversion speed conversion gain is obtained according to the ratio of the target acceleration and the actual acceleration. The shift speed is calculated by calculating and multiplying the conversion gain and the deviation rotation speed.

[0007]

The shift speed calculating means calculates the target acceleration according to the vehicle speed and the throttle opening, obtains the conversion gain of the shift speed according to the ratio of the target acceleration and the actual acceleration, and multiplies the conversion gain by the deviation rotational speed. Since the shift speed is calculated by using the shift speed, the obtained shift speed can be increased or decreased according to the vehicle speed or the driver's willingness to accelerate.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The continuously variable transmission shift control apparatus of FIG. 1 is a continuously variable transmission 3 on a power transmission system P connected to an engine 60 of a vehicle.
It is attached to 5. Here, the engine 60 is an electronically controlled fuel injection type 4-cycle engine, and includes an injector 1 for injecting fuel, an ignition plug 2 for igniting an air-fuel mixture, and the like.
Various devices are DBWE as electronic control means of engine
It is placed under the control of CU3, and this DBWECU3
A CVT ECU 21 which is an electronic control unit of the continuously variable transmission (CVT) 20 in the power transmission system P is connected to the. Note that a communication line is connected between the ECUs 3 and 21 so that signals can be constantly exchanged between the ECUs 3 and 21.

The DBWECU 3 is connected to an actuator 11 for driving a throttle valve 9 as an intake air amount operating means which is driven independently of the operation of an accelerator pedal 10 as an artificial operating member, and the CVTECU 21 has no actuator. An electromagnetic control valve 23 for hydraulically controlling the shift speed of the stage transmission 20 is connected.

Here, the overall construction of the engine 60 will be briefly described. The flow rate of the intake air sucked from the air cleaner element 5 is measured by the Karman vortex type air flow sensor 6 immediately after that. In addition to the air flow sensor 6, not shown devices such as an atmospheric pressure sensor and an atmospheric temperature sensor are provided in the air cleaner body 4, and various data relating to the intake air are measured and input to the DBWECU 3. It has a well-known configuration.

The amount of intake air flowing from the air cleaner body 4 into the throttle body 8 via the intake pipe 7 is controlled by the butterfly type throttle valve 9. The throttle valve 9 is driven to open and close by an actuator (in this embodiment, a step motor) 11 instead of the accelerator pedal 10 that the driver steps on. In this example,
A so-called DBW (drive-by-wire) system in which the actuator 11 is controlled by the DBWECU 3 is adopted. In the figure, reference numeral 12 is a throttle position sensor (hereinafter, throttle sensor) that outputs opening degree information of the throttle valve 9 as intake air amount information, and a detection signal thereof is input to the DBWECU 3.
The accelerator pedal 10 is provided with an accelerator opening sensor 13 as an acceleration request detecting means, and the depression amount θa is converted into an electric signal as driver's acceleration request information and input to the DBWECU 3.

The intake gas flows from the throttle body 8 into the intake manifold 15 via the surge tank 14, and becomes a mixture by the fuel injected from the injector 1 according to a command from the DBWECU 3. After the explosion / expansion process of the engine 60 is completed, the air-fuel mixture becomes exhaust gas, flows into the exhaust manifold 16, and after harmful components are removed via an exhaust gas purification device (not shown), it is released into the atmosphere from a muffler (not shown). Has been released. In addition, reference numeral 24 is an engine rotation sensor that outputs engine rotation information,
Reference numeral 39 indicates a water temperature sensor. The continuously variable transmission 20 of FIG. 4 is connected to the crankshaft of the engine 60 via a fluid coupling 41 and a planetary gear type forward / reverse switching device 42.

The continuously variable transmission 20 has a primary pulley 26 having a primary shaft 22 integrally connected to an output shaft of a forward / reverse switching device 42 and a secondary shaft 29 having a secondary shaft 29 for outputting a rotational force to the speed reducer 30 side. A pulley 28 is provided, and a steel belt 27 is stretched over the primary pulley 26 and the secondary pulley 28. The secondary shaft 29 is configured to transmit the rotational force to the drive wheels 32, 32 of the drive shaft 31 via a speed reducer 30 and a differential (not shown). Both pulleys 26, 28
Are both divided into two parts, and movable side pulley members 261 and 28
Reference numeral 1 is fitted onto the stationary pulley members 262 and 282 so as to be relatively non-rotatable and capable of contacting and separating at a relative interval. This movable pulley material 2
A primary cylinder 33 and a secondary cylinder 34, which are hydraulic actuators for operating a relative distance between the fixed pulley member and the fixed pulley member, are mounted on the reference numerals 61 and 281.

A pair of rotation sensors s1 and s2 for detecting both rotational speeds wp and ws of the primary pulley 26 and the secondary pulley 28 are mounted as means for detecting the actual gear ratio in (= wp / ws). In this case, the movable pulley member 261 is brought closer to the fixed pulley member 262 of the primary pulley 26 to increase the winding diameter of the primary pulley, and the movable pulley 281 is wound away from the fixed pulley member 282 of the secondary pulley 28. To reduce the actual gear ratio in (primary speed Wp
/ Secondary rotation speed Ws) is reduced, that is, a low gear ratio (high gear stage) is set, and the reverse operation is performed to obtain a high gear ratio (low gear stage).
Is configured to achieve. A hydraulic circuit of such a continuously variable transmission 20 will be described with reference to FIG. This hydraulic circuit is provided with an oil pump 37, and the oil discharged from the hydraulic circuit is a fluid coupling 41.
And the forward clutch 43 and the reverse clutch 44 of the forward / reverse switching unit 42, and the primary cylinder 45 and the secondary cylinder 46 of the continuously variable transmission 20.

Here, the oil pump 37 is driven according to the rotation of the engine to change its oil pressure. For this reason CVTE
In the CU21, the maximum allowable pressure of the same discharge pressure of the duty valve is regulated by the line pressure regulator valve 47,
Moreover, the solenoid valve 40 and the regulator valve 48 adjust the pressure so that the line pressure, which is a set value, is maintained.
A part of the line pressure passage 49 is connected to the clutch pressure control valve 50, and the pressure oil whose pressure is adjusted to a set value by the valve passes through the clutch oil passage 51 and the manual valve 5
2 is supplied. This manual valve 52 works in conjunction with a manual switching lever for switching the shift speed,
2 and L ranges, a reverse R range, and neutral N and parking P ranges.

In this range of the manual valve 52, the forward clutch 43 is engaged in the forward drive side D, 2, L, and at this time, the engine rotation is transmitted to the continuously variable transmission 20 as it is, while in the reverse drive R range, the engine rotation is transmitted. It is reversed and transmitted to the continuously variable transmission 20. A part of the line pressure path 49 is branched and regulated to a set value by the pressure control valve 53, the hydraulic pressure is supplied to the electromagnetic control valve 23, and the valve regulates the shift speed control pressure Pc according to the shift speed Vi. Is pressed. The electromagnetic control valve 54 is the CVT ECU 21.
And outputs a shift speed control pressure Pc corresponding to the shift speed signal to a shift ratio control valve 54 described later.

Primary cylinder 45 of continuously variable transmission 20
And the secondary cylinder 46 are respectively connected to the main port 541 and the sub port 542 of the gear ratio control valve 54,
In particular, the secondary cylinder 34 is also directly connected to the line pressure passage 49. Here, the gear ratio control valve 54 includes the main and sub ports 5
41 and 542, a pilot port 543 that receives the speed change control pressure Pc of the electromagnetic control valve 23, and a pressure adjusting port 5 that receives the adjustment pressure from the pressure control valve 53.
44 and a drain port X communicating with the oil tank 55, and the spool 56 controls the switching of the oil passage. Here, the spool 56 is its pilot port 5
The portion opposed to 43 receives the shift speed control pressure Pc in the left direction, and the other end receives the adjusting pressure and the spring force in the opposite direction, and switches to the balance position and moves. In this case, the spool 56
The drain port X is closed according to the right movement of (the shift speed control pressure Pc decreases), and is completely closed after a certain movement,
Furthermore, after a certain movement, the main port 541 and the sub port 542
, The primary pulley control oil pressure Pp of the primary cylinder 45 is increased (the secondary pulley control pressure is always the line pressure), the actual gear ratio in is decreased to a low gear ratio (high gear stage), On the contrary, the control oil pressure Pp can be decreased and the actual speed ratio in can be increased to achieve a high speed ratio (low speed stage).

Both the DBWECU 3 and the CVTECU 21 are composed of microcomputers as main components,
In the built-in memory circuit, the required power calculation map of FIG.
The reference torque calculation map of FIG. 6, the intake air amount calculation map of FIG. 7, the throttle opening calculation map of FIG. 8, the engine output control processing routine of FIG. 9, the CVT control processing routine of FIGS. The control programs of the ECU main routine of the DBWECU 3 of FIG. 12 are stored.

Here, the DBWECU 3 determines the accelerator opening θ
The required power Po of the driver is calculated from a, the target torque T is temporarily set according to this value and the engine speed Ne, and the torque correction amount ΔTe (friction loss correction by the water temperature etc.) is added to the temporarily set target torque T. Target engine torque T1
To calculate the target engine torque T1 and engine speed N
It has a function of calculating a throttle opening degree θs for obtaining e and controlling the valve 9 to the throttle opening degree θs. On the other hand, the CVTECU 21 calculates the target speed ratio io from the target engine speed Ne and the vehicle speed wv as the speed ratio calculation means, and the actual speed Wp of the primary pulley and the target primary pulley speed equivalent to the target speed ratio io as the deviation speed calculation means. The deviation rotation speed E1 from the number Wpo is calculated, the shift speed Vi is calculated based on the deviation rotation speed E1 as the shift speed calculation means, and the shift speed signal Du corresponding to the shift speed Vi is calculated as the shift driving means. The electromagnetic control valve 23 is driven, and in particular, the shift speed calculation means is a target acceleration G of the vehicle.
YB is calculated according to the vehicle speed V and the throttle opening θa, the conversion gain Ka of the shift speed Vi is calculated according to the ratio G / GYB of the target acceleration GYB and the actual acceleration G, and the conversion gain Ka and the deviation rotational speed E1 are calculated. It has a function of multiplying and calculating the shift speed Vi.

Hereinafter, the shift control device for the continuously variable transmission according to this embodiment will be described with reference to the control programs shown in FIGS. 9 to 12 and the block diagram shown in FIG. In this embodiment, the engine body 60 is started by operating an ignition key (not shown), and the DBWEC shown in FIGS.
Control within U3 and CVTECU 21 is also started. When the control is started, the DBWECU 3 executes the main routine of FIG. Here, the initial setting and the detection data of each sensor are read and taken into a predetermined area.

At step c2, it is judged whether or not the fuel cut zone is present based on the engine speed Ne based on the output of the engine speed sensor 24 and the engine load information based on the output of the air flow sensor 6 (here, the intake air amount A / N). Proceed to step c3, and the air-fuel ratio feedback flag
Clear the FBF, set the fuel cut flag FCF to 1, and return. When it is determined that the fuel is not cut and the process reaches step c5, the fuel cut flag FCF is cleared and it is determined whether or not a known air-fuel ratio feedback condition is satisfied. For example, at the time of the transient operation range such as the power operation range which is not satisfied, in step c12, the air-fuel ratio correction coefficient KMAP corresponding to the current operation information (A / N, N) is calculated,
This value is input to the address KAF, and the process proceeds to step c9.

When step c7 is reached on the assumption that the air-fuel ratio feedback condition is satisfied, here, the load information A
/ N and the target air-fuel ratio (target A / F) according to the engine speed Ne, the actual air-fuel ratio (A / F) n is calculated based on the output of the air-fuel ratio sensor 2, and the target air-fuel ratio ( Goal A
/ F) and the deviation ε between the actual air-fuel ratio (A / F) n are calculated, the well-known PID process is applied to the deviation air-fuel ratio ε, and the normal feedback coefficient KFB is set. And this value is the address KA
It is taken into F and it progresses to step c9.

At step c9, the other fuel injection pulse width correction coefficient KDT and the correction value TD of the dead time of the fuel injection valve are set according to the operating condition, and the routine proceeds to step c10. At step c10, the ignition timing θadv is set based on a predetermined map (not shown) so as to increase according to the engine speed Ne. After that, the process proceeds to an engine output control process, which will be described later, at step c11, and then returns to step c1. A fuel supply control routine (not shown) for controlling the injector 1 based on the air-fuel ratio feedback correction value KFB calculated in the main routine is executed based on a well-known control process, and similarly, the calculated ignition timing θ
An ignition drive routine (not shown) for outputting a control signal to the ignition circuit 17 to drive the spark plug 2 to adv is executed based on well-known control processing.

In the engine output control processing of FIG. 9, first, the detection data of each sensor, for example, the information such as the throttle opening θa and the engine speed Ne are fetched into a predetermined area. In step a2, the throttle opening θa is calculated based on the required power Po calculation map of FIG. 5, and the torque calculation map is obtained from the required power Po and the engine speed Ne (see FIG. 6).
Is used to set the reference torque To.

At steps a3 and a4, the water temperature information WT is fetched, the friction loss torque T _WT of the sliding portion is calculated from a predetermined map (see FIG. 2), and the friction loss torque T _WT is added to the required torque To to obtain the target. The torque T1 is determined and the process proceeds to step a5. Here, the intake air amount A / N corresponding to the target torque T1 and the engine speed Ne is obtained from the intake air amount calculation map of FIG. 7, and the throttle opening θs is calculated from the intake air amount A / N and the engine speed Ne as shown in FIG. Throttle opening θ
a Calculated based on the calculation map. At step a6, the difference between the throttle opening θa and the actual opening θn is calculated to obtain the deviation Δ
θ is obtained, an output Dun capable of eliminating this deviation Δθ is calculated, and the output Dun is output to the pulse motor 11 to drive the throttle valve 9 to generate the target torque T1 in the engine.

On the other hand, the CVTECU 21 is shown in FIGS.
The CVT control of No. 1 is entered, initialization is performed, and both rotational speeds wp and ws of the primary pulley 26 and the secondary pulley 28, throttle opening θa from the DBWECU 3 and engine rotational speed Ne which are detection data of each sensor. Others are captured and stored in a predetermined area. Step b
In 3 and b4, the target speed ratio io is calculated from the engine speed Ne and the vehicle speed wv, and the target primary pulley rotation speed Wpo corresponding to the target speed ratio io is calculated. Then, a deviation E1 (= Wpo-Wp) between the target primary pulley rotation speed Wpo and the actual primary pulley rotation speed Wp is calculated, and the process proceeds to step b5. In step b5, the actual primary pulley rotation speed Wp, that is, the first gain K1 is set in the first gain map (see FIG. 2) in order to reduce the response in response to the increase in the vehicle speed, and in step b6, the deviation E1 is set. (= Wp
o-Wp), the second gain K2 is set in the second gain map (see FIG. 2) so as to increase the responsiveness according to the increase of the absolute value | E1 |

In steps b7 to b9, the vehicle speed V is calculated from the actual primary pulley rotation speed Wp and the speed reduction ratio α on the speed reducer 30 side.
Is calculated, and the target acceleration GYB is calculated from the vehicle speed V and the throttle opening θa. After that, the differential value of the vehicle speed V is calculated, and the actual acceleration G is obtained. When step b10 is reached, the ratio G / GYB between the actual acceleration G and the target acceleration GYB is calculated. Even if the ratio G / GYB increases, that is, even if the throttle opening θa indicating the driver's intention to accelerate is larger than the actual acceleration G. , When the vehicle speed V is relatively low, the reference shift speed Vi
The acceleration gain Ka is set in the acceleration gain map (see FIG. 2) so as to hold down 1 and increase the responsiveness by incorporating the driver's intention of acceleration according to the increase of the vehicle speed V.

At step b11, the deviation E1 (= Wpo-
Wp) has the first and second gains K1 and K2 and the acceleration gain K.
A is multiplied to calculate the reference shift speed Vi1. Further, in steps b12 to b14, the unit average value ΔVi1 of the reference shift speed Vi1 input every unit time is integrated to calculate an integral term ΣΔVi1, and the integral term ΣΔVi1 is set to a predetermined variation range (30% to 70%). Clipping is performed, and the value is multiplied by the integral correction coefficient to calculate the integral corrected shift speed ViI.

In steps b15 to b17, the reference speed change speed Vi1 and the integral correction speed change speed ViI are added to obtain the speed change speed Vi, and the pair of cylinders 45, 46 are arranged so that the speed change speed Vi can be achieved by both pulleys 26, 28. The respective pulley control oil pressures Pp, sP are calculated, and further, the shift speed control pressure Pc capable of adjusting the pulley control oil pressures Pp, sP is calculated,
The shift speed control pressure signal Du corresponding to the shift speed control pressure Pc is calculated, the electromagnetic control valve 23 is driven by the signal Du, and the continuously variable transmission 20 can be brought close to the target speed ratio io at the shift speed Vi.

[0030]

As described above, in the shift control device for a continuously variable transmission according to the present invention, the shift speed calculating means calculates the target acceleration according to the vehicle speed and the throttle opening, and according to the ratio of the target acceleration and the actual acceleration. The speed change speed gain is calculated by multiplying the speed change speed conversion gain with the deviation rotation speed, and the speed change speed thus obtained can be increased or decreased according to the vehicle speed or the driver's willingness to accelerate. The driving feeling when switching the ratio can be further improved, the engine power consumption can be suppressed only by the rotation increase of the primary pulley during kickdown, and the vehicle speed can be increased with a good driving feeling as the throttle opening increases. I can.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a shift control device for a continuously variable transmission according to an embodiment of the present invention.

FIG. 2 is a functional block diagram of an electronic control unit in the apparatus of FIG.

FIG. 3 is a hydraulic circuit diagram of a continuously variable transmission used by the apparatus of FIG.

4 is a cross-sectional view of a main part of a continuously variable transmission used by the device of FIG.

5 is a characteristic diagram of a required power calculation map adopted by the electronic control unit in the apparatus of FIG.

6 is a characteristic diagram of a reference torque calculation map used by the electronic control unit in the apparatus of FIG.

FIG. 7 is a characteristic diagram of an intake air amount calculation map adopted by the electronic control device in the device of FIG.

FIG. 8 is a characteristic diagram of a throttle opening calculation map adopted by the electronic control unit in the apparatus of FIG.

9 is a flowchart of an engine output control processing routine adopted by the electronic control unit in the apparatus of FIG.

10 is a CV adopted by the electronic control unit in the apparatus of FIG.
It is a flowchart of the front part of a T control processing routine.

11 is a CV adopted by the electronic control unit in the apparatus of FIG. 1;
It is a flowchart of a T control processing routine rear part.

FIG. 12 is an EC adopted by the electronic control unit in the apparatus of FIG.
It is a flowchart of a U main routine.

FIG. 13 is a functional block diagram of an electronic control device in a conventional device.

[Explanation of symbols]

 3 DBWECU 20 continuously variable transmission 12 throttle opening sensor 20 continuously variable transmission 21 CVT ECU 23 electromagnetic control valve 26 primary pulley 27 drive belt 28 secondary pulley 33 primary cylinder 34 secondary cylinder 54 gear ratio control valve s1 rotation sensor s2 rotation sensor Pc Shift speed control pressure

Claims (1)

[Claims] 1. A pair of drive belts mounted on a primary pulley and a secondary pulley, around which a drive belt is wound, and for increasing and decreasing each pulley gap so that a winding diameter ratio of both pulleys has a value corresponding to a predetermined gear ratio. Hydraulic deviation actuator, deviation rotation speed calculation means for calculating a deviation rotation speed between the actual rotation speed of the primary pulley and a target primary pulley rotation speed corresponding to a designated target gear ratio, and a shift speed based on the deviation rotation speed. A shift speed calculating means for calculating, a shift driving means for calculating a shift speed signal according to the shift speed to drive the electromagnetic control valve, and a shift speed control pressure generated by the electromagnetic control valve according to the shift speed signal. And a gear ratio control valve for adjusting the pulley control oil pressures of the pair of hydraulic actuators to drive both pulleys to a target gear ratio. The degree calculation means calculates the target acceleration of the vehicle according to the vehicle speed and the throttle opening, calculates the conversion gain of the shift speed according to the ratio of the target acceleration and the actual acceleration, and multiplies the conversion gain by the deviation rotational speed. A shift control device for an continuously variable transmission, wherein: