JPH0737823B2 - Shift control device for continuously variable transmission for vehicle - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a continuously variable transmission for vehicles.

[0002]

2. Description of the Related Art Conventionally, in such a control device, (a) an engine speed is set to a target value, (b) an engine speed change speed is set to a target value, and (c) a gear ratio is set to a target value. It is general to control the value.

[0003]

However, in the above-mentioned prior art, the acceleration predicted from the surplus horsepower of the engine is not taken into consideration. For this reason, the amount of change in the gear ratio tends to be more or less than necessary, and (a)
A shift delay due to a small speed change ratio change speed during shift control on the “high” side of the gear ratio and a sense of discomfort due to it (decreased responsiveness)
May occur, (b) during the shift control on the “gear” side of the gear ratio, deterioration of fuel efficiency and discomfort may occur due to the engine speed rising, and (c) during shift control on the “gear ratio” side. Hunting of the engine speed may occur due to a small speed change rate of the gear ratio, or (d) deterioration of fuel efficiency may occur due to efficiency reduction due to excessive gear shift during deceleration.

The present invention has been made in view of the above circumstances, and calculates the speed change speed as the sum of the component corresponding to the predicted acceleration and the component corresponding to the target change speed of the engine speed, By using the speed change ratio change speed as a control value, the above problem is solved, and the accuracy of setting the target speed change of the engine speed is improved, and thus the control accuracy of the vehicle continuously variable transmission is improved. An object of the present invention is to provide a shift control device.

[0005]

An apparatus according to the first aspect of the present invention calculates a predicted horsepower Pa of an engine and a predicted acceleration dV / dt of a vehicle based on the surplus horsepower Pa. The driver's addition of the predicted acceleration calculation means, the engine speed sensor for detecting the engine speed N, the vehicle speed sensor for detecting the vehicle speed V, and the difference ΔN between the target engine speed N ₀ and the actual engine speed N. , A target deceleration rate dN ₀ / dt of the engine speed based on an acceleration / deceleration index determination means defined as an index indicating a deceleration intention, and a map or a table predetermined according to the difference ΔN.
Target change speed determining means for setting
₀ / dt, the vehicle speed V and the engine speed N and di / dt = -C × the following equation on the basis of the ^{(N / V 2) × dV} / dt + C ×
(1 / V) × dN ₀ / dt C: constant Gear ratio change speed calculation means for calculating the gear ratio change speed di / dt, and the gear ratio i is changed at the calculated gear ratio change speed di / dt. And an operation control means for controlling the operation of the continuously variable transmission.

According to a second feature of the present invention, in addition to the first feature, the map or table includes:
When the difference ΔN indicates that the vehicle is in an accelerating state, when ΔN is small, the target change speed dN ₀ /
When the amount of change in dt is small, when ΔN is medium, the target change speed dN ₀ / dt of the engine speed is large, and when ΔN is large, target change speed dN ₀ / d of the engine speed is large.
The change amount of t is set as small.

Further, according to a third aspect of the present invention, in addition to the second aspect, when the map or table indicates that the difference ΔN is in a deceleration state, the engine speed The change amount of the target change speed dN ₀ / dt is set smaller than that in the acceleration state.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, referring to FIG. 1, a hydraulic continuously variable transmission T of an automobile has a constant discharge hydraulic pressure having an input shaft 1 driven by an engine E. A pump 2 and a variable displacement hydraulic motor 4 having an output shaft 3 for driving wheels W and arranged on the same axis as the hydraulic pump 2 are connected to each other to form a closed hydraulic circuit 5. Become. That is, the discharge port of the hydraulic pump 2 and the suction port of the hydraulic motor 4 are connected to each other by the high pressure oil passage 5 _H , and the low pressure oil passage 5 _L is connected between the discharge port of the hydraulic motor 4 and the suction port of the hydraulic pump 2. Are connected to each other.

A short circuit 6 is connected to the high pressure oil passage 5 _H and the low pressure oil passage 5 _L , and a clutch valve 7 is provided in the middle of the short circuit passage 6. Further, the discharge port of the replenishment pump 8 driven by the input shaft 1 is connected to the high-pressure and low-pressure oil passages 5 _H and 5 _L via the check valves 9 and 10, and the hydraulic oil pumped from the oil tank 12 has a shortage. It is supplied to the hydraulic closed circuit 5 for replenishment. Further, a relief valve 13 is provided between the suction and discharge ports of the replenishment pump 8.

The clutch valve 7 is controlled to be opened and closed by an opening and closing control device (not shown).
The power transmission between the input shaft 1 and the output shaft 3 is controlled according to the opening degree of the.

The control of the gear ratio i is obtained by continuously changing the displacement of the hydraulic motor 4 by the hydraulic cylinder 15 for the hydraulic pump 2 that discharges a constant displacement. For example, when the capacity of the hydraulic motor 4 is changed to the "large" side, the gear ratio i is changed to the "large" side, and when the capacity of the hydraulic motor 4 is changed to the "small" side, the gear ratio i is changed to the "small" side. Changes to. As a result, a continuously variable shift between the engine E and the wheels W of the vehicle can be obtained.

The hydraulic motor 4 changes the capacity by changing the inclination angle of the swash plate 4a.
a is connected to the hydraulic cylinder 15 via a link 16.

The hydraulic cylinder 15 includes a cylinder body 17 and
A piston 20 which is slidably fitted into the cylinder body 17 to divide the interior of the cylinder body 17 into a head chamber 18 and a rod chamber 19.
And a piston rod 21 which is integrated with the piston 20 and penetrates the end wall of the cylinder body 17 on the rod chamber 19 side in an oil-tight and movable manner. The piston rod 21 is connected to the hydraulic motor via the link 16. 4 is connected to the swash plate 4a.

In this connection structure, when the piston 20 moves to the left in the direction of contracting the volume of the rod chamber 19, the swash plate 4a of the hydraulic motor 4 tilts in the direction of making the capacity "large" and the gear ratio i becomes " When the piston 20 moves to the right in the direction of contracting the volume of the head chamber 18, the swash plate 4a of the hydraulic motor 4 tilts in the direction of "small" and the gear ratio i becomes "small". It changes to the side.

An oil passage 22 is connected to the head chamber 18 of the hydraulic cylinder 15, and an oil passage 23 is connected to the rod chamber 19. A solenoid valve 24 is provided between the oil passage 22 and the oil tank 12. The oil passage 23 is connected to a supply oil passage 25 connected to the high pressure oil passage 5 _H of the hydraulic closed circuit 5, and the supply oil passage 25 is connected midway in the oil passage 22 via a solenoid valve 26. Both solenoid valves 24, 26 are duty-controlled by a control means 27 such as a microcomputer, and the duty control controls the operating speed of the hydraulic cylinder 15, that is, the changing speed di of the gear ratio i.
/ Dt is controlled.

The control means 27 includes a throttle opening sensor 28, an engine speed sensor 29, and an intake negative pressure sensor 3.
0, the vehicle speed sensor 31 and the swash plate angle sensor 32 of the hydraulic motor 4 are connected. Thus, the control means 27 calculates a surplus horsepower Pa of the engine, a surplus horsepower calculation means, a predicted acceleration calculation means of calculating a predicted acceleration dV / dt of the vehicle based on the surplus horsepower Pa, and a target engine speed N _0.
Difference between the engine speed N and the actual engine speed N is set as an index indicating the driver's intention to accelerate or decelerate, and the engine speed is determined based on a deceleration index determining means and a map or table predetermined according to the difference ΔN. Target rate of change dN
₀ / dt, a target change speed determining means, and a gear ratio change speed calculating means for calculating a gear ratio change speed di / dt based on the target change speed dN ₀ / dt, the vehicle speed V and the engine speed N. Calculated speed ratio change speed di / d
It has a function as an operation control means for controlling the operation of the solenoid valves 24 and 26 according to t.

Here, the gear ratio i is the engine speed N,
When the vehicle speed is V, it is expressed by Equation 1.

I = N / (C ′ × V) (1) In the above formula 1, C ′ is a constant. Further, when the gear ratio change speed di / dt is obtained by differentiating the formula 1 with respect to the time t, the formula 2 is obtained.

Di / dt = {1 / (C ′ × V)} × [dN / dt-
{N / (C ′ × V)} × C ′ × dv / dt] (2) In Equation 2, the engine speed change rate dN / dt is set as the target engine speed change rate dN ₀ / dt. C = 1 /
If C'is given, Equation 3 is obtained. di / dt = -C × (N / V 2) × dV / dt + C × (1 / V) × dN 0 / dt ......
(3) That is, the speed change ratio di / dt is the acceleration dV / d.
component di _a / dt} = − C × (N / V ² ) × corresponding to t
dv / dt} and the target change speed dN ₀ of the engine speed.
A component corresponding to / dt {= C × (1 / V) × dN ₀ / d
t} will be given. At this time, dV / d
When t is a predicted acceleration, the predicted acceleration dV / dt is obtained by Expression 4 to Expression 7.

That is, the output Pe of the engine E alone is
When the road surface resistance is Rμ, the air resistance is Ra, and the surplus horsepower of the engine E is Pa, it is expressed by Pe = Rμ + Ra + Pa (4). From Equation 4, the surplus horsepower Pa is Pa = Pe− (Rμ + Ra) (5). The engine surplus horsepower Pa is energy capable of accelerating the entire vehicle at the time of its control cycle. The total vehicle weight is W, and the total engine rotation weight with respect to the energy used for inertial rotation when the engine is rotating is ΔW. Then, it is also expressed by Equation 6.

[0021] Pa = (W + ΔW) × (1 / g) × dV / dt × (V × 10 3/60 2) × (1/75) ...... (6) Equation 7 from the equation 6 is obtained. dV / dt = Pa × g × [60 ³ / {(W + ΔW) × (V × 1
0 ³ )}] × 75 (7) Therefore, the predicted acceleration dV / dt can be calculated from the surplus horsepower Pa of the engine E, and the surplus horsepower Pa is calculated by Equation 5
Required from. On the other hand, the target speed of change dN ₀ / dt of the engine speed is calculated by calculating the difference ΔN between the target engine speed N ₀ and the actual engine speed N as an index indicating the driver's intention to accelerate or decelerate. From the viewpoint of ring and fuel consumption, the target change speed dN ₀ according to the difference ΔN.
It is obtained by preparing a table or map in which / dt is predetermined.

The control procedure of the control means 27 will now be described. In FIG. 2, the engine speed N and the vehicle speed V are read in the first step S1. In the next second step S2, the surplus horsepower Pa is calculated.
The calculation of the surplus horsepower Pa is performed based on the mathematical expression 5, and the engine single unit output Pe is obtained by a map as shown in FIG. 3, for example. That is, in FIG. 3, the engine speed N is plotted on the horizontal axis, and a plurality of intake negative pressures P _{1 to} P ₁₃ indicated by suffixes 1 to ₁₃ are used as parameters, and the vertical axis indicates the engine output Pe. , The engine speed N and the intake negative pressure determine the engine unit output Pe.

Thus, the surplus horsepower Pa of the engine E is obtained, and as a result, the predicted acceleration dV / dt is obtained from the equation 7 in the third step S3. Therefore, in the next fourth step S4, the predicted acceleration component di _a / dt of the speed ratio change speed di / dt is calculated.

In the fifth step S5, the target change speed dN ₀ / dt of the engine speed is obtained. That is, as shown in FIG. 4, the target shift speed dN ₀ corresponding to the difference ΔN between the target engine speed N ₀ and the actual engine speed N.
/ Dt is obtained in advance, and the target change speed dN ₀ / dt corresponding to the difference ΔN is calculated.

In FIG. 4, when the difference ΔN is “+”, that is, when the vehicle is in an accelerating state, the region R in which ΔN is small is shown.
Change amount of the target change rate dN ₀ / dt of the engine speed change amount of the target change rate dN ₀ / dt of the engine rotational speed is small, in the region R _PM is in the .DELTA.N in _PL is large, .DELTA.N large Target change speed dN ₀ of the engine speed in the region R _PH
The change amount of / dt is set to be small, and the difference ΔN
Is "-", that is, in the deceleration state, the target change speed dN ₀ of the engine speed in the region R _ML in which ΔN is small.
A region R in which the amount of change in / dt is set to be smaller than the amount of change in the region R _PL in the acceleration state and ΔN is medium.
_{In MH} , the amount of change in the target change speed dN ₀ / dt of the engine speed in the region R _MH in which the change amount is set to be smaller than the change amount in the region R _PM when the acceleration state is large, and the change amount in the acceleration state is Is set smaller than the amount of change in the region R _PL .

With this setting, in the acceleration state where the accelerator operation amount is small, that is, in the region R _PL , the change amount of the target change speed dN ₀ / dt is small, so that the influence of the unevenness of the road surface and the accelerator pedal will be changed. Contrary to the above, a stable driving condition can be obtained even when a minute operation is performed, and a good driving feeling can be obtained, and an intermediate region, that is, a region R having an acceleration intention.
_{In the PM} , it is necessary to increase the engine output with a linear feeling corresponding to the accelerator operation amount, and the target change speed dN ₀ / d considering the output loss accompanying the increase in the engine speed for that is required.
The amount of change is t, and a stable acceleration feeling can be obtained in the region R _PH .

Further, since the accelerator pedal is released when the brake operation is required, in the region R _MH where the deceleration is large, if the amount of change of the target change speed dN ₀ / dt is large, the effect of engine braking is deteriorated, While a large change in the engine speed is troublesome, such a problem does not occur because the change amount is small.

In the next sixth step S6, the engine speed target speed change speed dN ₀ / d of the speed ratio change speed di / dt.
The component di _N / dt corresponding to t is calculated.

Thereafter, in a seventh step S7, the gear ratio change speed di / dt is calculated based on Formula 3, and the solenoid valves 24 and 26 are controlled using the calculated value as a control value.

By the way, when the surplus horsepower is obtained in the second step S2 of FIG. 2, the engine unit output Pe obtained in FIG. 3 is determined irrespective of the mission efficiency, and an accurate engine output is obtained. Needs to be corrected by mission efficiency. The mission efficiency is determined by the engine output Pe and the engine speed N, but to be more accurate, it needs to be further corrected by the shift position. That is, the mission efficiency η _M is obtained by the product (η _M = ηm × Kμ) of the mission efficiency ηm determined by the engine output Pe and the engine speed N and the gear ratio coefficient Kη determined by the gear ratio i. , The mission efficiency ηm is given in FIG. 5, and the gear ratio coefficient Kη is given in FIG.

In FIG. 5, the engine speed N is taken as the horizontal axis,
A plurality of engine unit outputs Pe shown by adding subscripts 1 to 13
Mission efficiency η is plotted on the vertical axis using _{1 to} Pe ₁₃ as parameters.
m is shown, and in FIG. 6, the gear ratio i is shown on the horizontal axis and the gear ratio coefficient Kη is shown on the vertical axis. This FIG. 5 and FIG.
The map indicated by is prepared in advance.

Therefore, during the calculation of the second step S2 in the flowchart of FIG. 2, the single engine output Pe is corrected by the subroutine shown in FIG. That is, in the first step L1, the engine unit output Pe is obtained from FIG. 3 described above, and the mission efficiency ηm is obtained from the map shown in FIG. 5 in the second step L2. In the next third step L3, the gear ratio i obtained by the swash plate angle sensor 32 is read, and in the fourth step L4, the gear ratio coefficient Kη is calculated from the map shown in FIG. Thereafter, the mission efficiency η _M is calculated in the fifth step L5, and the engine output Pe is corrected in the sixth step L6 by this mission efficiency η _M. Therefore, the extra horsepower Pa and the predicted acceleration dV / are calculated based on the more accurate engine output.
dt will be obtained more accurately.

If the predicted acceleration dV / dt obtained by the equation 7 based on the surplus horsepower Pa obtained by the equation 5 is a flat road reference, the predicted acceleration component di _a / dt of the speed change ratio di / dt. May deviate depending on road surface conditions, and the engine speed N may rise or fall below a planned value, which may be unfavorable in terms of driving performance. Therefore, the previous predicted acceleration dV _n-1 / dt and the result dV _n
It is determined whether the running resistance is higher or lower than the predicted level based on the difference with / dt, and the difference (dV _n-1 / dt-dV _n
/ Dt), the predicted acceleration component di _a / dt is corrected.

That is, the previous predicted acceleration dV _n-1 / d
t is obtained by Expression 7, and the result dV _n / dt is obtained by subtracting the current vehicle speed V _n from the previous vehicle speed V _n−1 and dividing by the time Δt.

DV _n / dt = (V _n-1 −V _n ) / Δt Accordingly, the correction value Δ (dV / dt) is Δ (dV / dt) = (dV _n−1 / dt−dV _n / dt) ×
kk: correction coefficient The predicted acceleration component di is calculated from this correction value Δ (dV / dt).
Correct _a / dt.

Therefore, the fourth part of the flowchart shown in FIG.
When the predicted acceleration component di _a / dt is calculated in step S4, the predicted acceleration component di _a / dt is corrected by a subroutine as shown in FIG.

In the first step m1, the engine speed N
e, the current vehicle speed V _n and the previous vehicle speed V _n-1 are read, dV _n / dt is calculated in the second step m2, and Δ (dV / dt) is calculated in the third step m3. Based on the result, the predicted acceleration component di is calculated in the fourth step m4.
_a / dt _{is, di a / dt = -C ×} (N / V 2) × (dV / dt + Δd
V / dt) is corrected.

Further, assuming that the target change speed dN ₀ / dt of the engine speed obtained in FIG. 4 is a flat road surface reference, the target change due to aging of the transmission, when driving on a slope or when wind is strong. The speed dN ₀ / dt tends to shift. Therefore, the previous predicted target change speed dN _on-1 / dt
If, as a result such as running resistance by the difference between dN _on / dt it is determined whether a small or a larger than expected levels, corresponding to the difference _{(dN on-1 / dt-} dN on / dt) , The engine speed target change speed component di _N / dt is corrected.

That is, the previous predicted target change speed dN
_on-1 / dt is obtained from the map of FIG. 4 and the result dN _on /
dt is obtained by subtracting the current engine speed N _n from the previous engine speed N _n−1 and dividing by the time Δt. dN _0n / dt = (N _n-1 −N _n ) / Δt Accordingly, the correction value Δ (dN / dt) becomes (dN _n-1 / dt
-DN _n / dt), and this correction value Δ (dN /
dt) engine speed target change speed component di _N /
Correct dt.

Then, the sixth step of the flow chart shown in FIG.
In step S6, the engine speed target change speed component di _N
When calculating / dt, the engine speed target change speed component di _N / d is calculated by a subroutine as shown in FIG.
Correction of t is performed.

At the first step q1, the previous engine speed N _n-1 , the current engine speed N _n and the vehicle speed V are read, and at the second step q2, dN _n / dt is calculated. Further, in the third step q3, Δ (dN / d
t) = (dN _n-1 ) / dt-dN _n / dt) is calculated,
Based on the result, in the fourth step q4, the engine speed target change speed di _N / dt is di _N / dt = C × (1 / V) × (dN / dt + ΔdN
/ Dt) is corrected.

Next, the operation of this embodiment will be described. The speed ratio change speed di / dt is calculated as the predicted acceleration component di _a.
/ Dt and engine speed target change speed component di _N / d
calculated as the sum of t and the speed ratio change rate di / dt
Is controlled as a control value, the change amount of the gear ratio is properly controlled. For example, di _N / dt when dN ₀ / dt is constant is shown by the curve A in FIG.
When / dt is constant, di _a / dt is shown by the curve B in FIG. 10, and di / dt is shown by the curve C.

As is apparent from FIG. 10, the speed ratio change speed di / dt on the "high" speed ratio side is small at low speeds as compared with the conventional one in which the predicted acceleration component di _a / dt is not taken into consideration. Therefore, there is no delay in shifting and an unpleasant sensation associated therewith, or hunting of the engine speed. Further, the engine speed does not rise up during the shift control on the “small” gear ratio side, so that it is possible to avoid the deterioration of fuel efficiency and the occurrence of discomfort, and also to reduce the efficiency due to overshifting during deceleration. Absent.

Moreover, the engine unit output Pe used when calculating the predicted acceleration component di _a / dt is corrected by the mission efficiency η _M , so that a more accurate engine unit output P is obtained.
The predicted acceleration component di _a / dt can be calculated using e, and the control accuracy is improved.

Since the predicted acceleration dV / dt is corrected by the difference between the previous predicted value dV _n-1 / dt and the result dV _n / dt, the predicted acceleration component di corresponding to the road surface condition.
It is possible to obtain _a / dt, and it is possible to prevent the engine speed N from deviating from the planned value and to obtain excellent driving performance.

Further, the engine speed target change speed dN ₀
/ Dt is the previous target value dN _on-1 / dt and its result dN
Since it is corrected by the difference between _n / dt, the changing speed d approaching the target engine speed N ₀ regardless of the running condition.
The target engine speed N ₀ can be reached while avoiding the deviation of N ₀ / dt from the preset pattern.

Further, with respect to the target change speed dN ₀ / dt, the difference ΔN between the target engine speed N ₀ and the actual engine speed N is used as an index indicating the driver's intention to accelerate or decelerate, and the difference ΔN is calculated according to the difference ΔN Since the target change speed dN ₀ / dt of the engine speed is predetermined on the map or table, the optimum di / dt according to the acceleration / deceleration state can be obtained, and the drivability can be improved. it can.

[0048]

As described above, according to the first aspect of the present invention, a shift delay to the "large" side of the gear ratio at a low speed and a sense of discomfort associated therewith, and an occurrence of engine speed hunting occur. In addition, it is possible to prevent the deterioration of fuel efficiency and the occurrence of discomfort during the speed change control to the “small” gear ratio side, and to prevent the deterioration of fuel efficiency during deceleration.
It is possible to improve drivability by obtaining an appropriate speed change ratio according to the deceleration state.

Further, according to the second feature of the present invention, it is possible to obtain a target change speed of the engine speed that appropriately corresponds to a change in the acceleration state, and obtain a better driving feeling in the acceleration state.

Further, according to the third feature of the present invention, it is possible to obtain the target change speed of the engine speed that appropriately corresponds to the deceleration state and to obtain a better driving feeling in the deceleration state.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of a continuously variable transmission.

FIG. 2 is a flowchart showing a control procedure.

FIG. 3 is a diagram showing a map for obtaining an engine output.

FIG. 4 is a diagram showing a map for obtaining an engine speed target change speed.

FIG. 5 is a diagram showing a map for obtaining mission efficiency.

FIG. 6 is a diagram showing a map for obtaining a shift coefficient.

FIG. 7 is a flowchart of a subroutine for correcting the engine output.

FIG. 8 is a flowchart of a subroutine for correcting a predicted acceleration.

FIG. 9 is a flowchart of a subroutine for correcting the engine speed target change speed.

FIG. 10 is a graph showing an example of a speed change ratio change speed.

[Explanation of symbols]

 29 engine speed sensor 31 vehicle speed sensor T continuously variable transmission

Claims (3)

[Claims] 1. A surplus horsepower calculating means for calculating a surplus horsepower Pa of an engine, a predictive acceleration calculating means for calculating a predicted acceleration dV / dt of a vehicle based on the surplus horsepower Pa, and an engine rotation for detecting an engine speed N. Number sensor (29)
And a vehicle speed sensor (31) for detecting the vehicle speed V, and a deceleration index determining means for determining a difference ΔN between the target engine speed N ₀ and the actual engine speed N as an index indicating the driver's intention to accelerate or decelerate. And a target change speed determining means for setting a target change speed dN ₀ / dt of the engine speed based on a map or a table predetermined according to the difference ΔN, a target change speed dN ₀ / dt, a vehicle speed V and Based on the engine speed N and the following equation, di / dt = −C × (N / V ² ) × dV / dt + C ×
(1 / V) × dN ₀ / dt C: constant Gear ratio change speed calculation means for calculating the gear ratio change speed di / dt, and the gear ratio i is changed at the calculated gear ratio change speed di / dt. Of the continuously variable transmission (T), and an operation control means for controlling the operation of the continuously variable transmission (T). 2. When the difference ΔN indicates an acceleration state, the map or the table shows that when ΔN is small, the amount of change in the target change speed dN ₀ / dt of the engine speed is small. , setting the change amount of the target change rate dN ₀ / dt of the engine rotational speed is as small when the change amount of the target change rate dN ₀ / dt of the engine rotational speed is large, .DELTA.N is large when .DELTA.N of medium The shift control device for a continuously variable transmission for a vehicle according to claim 1, wherein: The method according to claim 3, wherein the map or table, when indicating that the difference ΔN is in a deceleration state, the change amount of the target change rate dN ₀ / dt of the engine rotational speed is smaller than that when the accelerating condition It is set, The claim 2 characterized by the above-mentioned.
A shift control device for a continuously variable transmission for a vehicle as described above.