JPH11108179A - Control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively suppress reduction of durability of a frictional element of a fastened side by inhibiting a jump shift, when car speed is larger than a prescribed value, and when a target shift stage having more than one stage level larger than a stage level of a target shift stage which is set previously. SOLUTION: Each signal from each sensor 301 to 306 such as car speed is inputted into a control unit 300, and operations of respective solenoid valves 111, 112, 121 to 123, 131 in a hydraulic control unit 100 are controlled according to an operating condition and the like in a vehicle or an engine. It is inhibited that gear speed is shifted with jumping-over into an up-shift when a detecting value of a car speed sensor 301 is larger than a prescribed value, and when a target shift stage having one more than stage level larger than a stage level of a target shift stage which is set previously. It is inhibited that gear speed is changed with jumping-over at the time of high speed, and thereby, reduction of durability of a fastening side frictional element is suppressed. Also at the time of low speed, it is approved that gear speed is shifted with jumping-over without applying a large load on the fastening side frictional element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a control device for an automatic transmission mounted on a motor vehicle, and more particularly, to an automatic transmission having improved control of a so-called jumping speed between two or more different speeds. Belongs to the technical field of transmission control devices.

[0002]

2. Description of the Related Art Generally, an automatic transmission mounted on an automobile combines a torque converter and a transmission gear mechanism,
The power transmission path of the transmission gear mechanism is switched by a selective operation of a plurality of friction elements such as a clutch and a brake to automatically shift to a predetermined gear.
In this case, the target shift speed which is the target of the shift is usually the vehicle speed, the throttle opening of the engine, that is, the driving state of the vehicle such as the engine load, and the driving state as a parameter, the higher the vehicle speed, the lower the load. The gear is set based on a shift characteristic that is provided in advance so that a gear with a higher gear is selected. Then, the automatic shift is achieved by controlling the engagement state of the friction element so that the target shift speed set as described above is realized.

[0003] Therefore, depending on how the operating state changes, the first gear, such as a 1-2 gear shift or a 3-2 gear shift, is required.
It is not a general shift between different gears,
A so-called jump shift may be performed between two or more shift speeds, such as a 1-3 shift or a 4-2 shift. In particular, for example, when the driver depresses the accelerator pedal and accelerates, and the accelerator pedal is returned after suddenly stopping the depression, a so-called back-out upshift with the decrease in the throttle opening occurs. At this time, if the amount of return of the accelerator is large and thus the throttle opening greatly decreases,
The gear difference between the target gear position according to the previous gear change command and the target gear position according to the current gear shift command is not two but two or more, and as a result, the gear shift is 1-3 gear shift, 2-4 gear shift, etc. Is performed.

In such a case, generally, in the upshift shift control, the rotation speed of the turbine shaft of the torque converter (turbine rotation speed) is controlled to a predetermined rate by performing feedback control of the engagement operation of the engagement-side friction element. Since the rotational speed before the shift is reduced to the rotational speed after the shift while making them coincide with each other, even in the case of the same upshift, in the case of an intermittent shift such as a 2-4 shift, 2-3. Since the deviation of the turbine speed before and after the shift, that is, the amount by which the turbine speed must be reduced, is larger than that in the upshift between adjacent shift speeds such as the shift and the 3-4 shift. The load on the fastening-side friction element described above increases, and a problem concerning its durability arises.

In view of the above, conventionally, such an overshifting shift of an upshift is permitted only when the throttle opening is equal to or less than a predetermined value and the torque is small, and is prohibited in other cases. I tried to avoid as much load as possible.

[0006]

However, in such a conventional technique, the target shift speed according to the previous shift command and the target shift speed according to the current shift command differ from each other by two or more, Therefore, when it is determined that the jump shift should be performed, if the throttle opening is equal to or less than the predetermined value, the jump shift of the upshift is permitted, and the driver performs the accelerator depressing operation during the jump shift operation. In this case, torque is generated at that time, and a large load is applied to the engagement-side friction element, so that the problem of reduced durability of the friction element again occurs.

In this case, a new target shift speed is set when the driver steps on the accelerator, and if the shift control is shifted to the shift control to the new target shift speed, the initial jump is performed. The shift is interrupted, and as a result, the problem of the durability of the engagement-side friction element being reduced is reduced. However, when performing a multiple shift when a second target shift speed different from the first target shift speed is set during the shift to the first target shift speed, the shift to the second target shift speed is performed. This is a control that is difficult to shift to, and as a result, the timing of switching between the engagement side friction element and the release side friction element is shifted, etc. In such a case, for example, as disclosed in Japanese Patent Publication No. 5-50621, shifting from the first shift to the second shift is prohibited and the first shift is prohibited.
The second shift is performed after the completion of the shift. Therefore, even if, for example, the accelerator pedal is depressed during the operation of the 2-4 upshift jump speed and another new target gear speed such as the second speed or the third speed is set, the shift to the new target gear speed is performed. Therefore, the first jump shift is completed to the end without any change, and therefore, the problem of deterioration in durability of the engagement-side friction element cannot be avoided.

Accordingly, an object of the present invention is to provide a control device for an automatic transmission that can more effectively suppress a decrease in the durability of a friction element that is engaged at the time of an upshift jump.

[0009]

In order to solve the above problems, the present invention uses the following means.

First, the invention described in claim 1 of the present application (hereinafter referred to as a "first invention") selectively connects a torque converter and a speed change gear mechanism to each other to form the gear mechanism. A plurality of frictional elements for realizing a plurality of shift speeds by switching a power transmission path; a driving state detecting means for detecting a driving state of the vehicle; and a target gear position set based on a detection result of the detecting means. A control device for an automatic transmission, comprising: a target gear position setting means for performing the control, and a control means for controlling an engagement state of the friction element such that the gear is shifted to the target gear position set by the setting means. A vehicle speed detecting means for detecting a value relating to the vehicle speed; and, when the value relating to the vehicle speed detected by the detecting means is greater than a predetermined value, a gear position of the target gear previously set by the target gear setting means. When a target gear position higher than the target gear position by 2 or more is set this time, a jump speed change inhibiting means for inhibiting a direct shift from the previously set target gear position to the currently set target gear position is provided. It is characterized by being.

Next, the invention according to claim 2 (hereinafter referred to as “second
Invention ". ) Has a torque converter, a speed change gear mechanism, and a plurality of friction elements that are selectively fastened to realize a plurality of shift speeds by switching a power transmission path of the gear mechanism, and also controls the driving state of the vehicle. Operating state detecting means for detecting, target gear setting means for setting a target gear based on a detection result of the detecting means, and the friction so as to perform a shift to the target gear set by the setting means. A control device for an automatic transmission, comprising: control means for controlling an engagement state of elements; a vehicle speed detection means for detecting a value related to a vehicle speed; an engine load detection means for detecting a value related to an engine load; When at least one of the value related to the vehicle speed or the value related to the engine load detected by the means is equal to or greater than a predetermined value, the value set by the target gear position setting means in the last time is set. When a target shift speed that is at least two gears higher than the target shift speed is set this time, a jump shift prohibition unit that inhibits a direct shift from the previously set target shift speed to the currently set target shift speed. Are provided.

Further, the invention according to claim 3 (hereinafter referred to as “third
Invention ". ) Has a torque converter, a speed change gear mechanism, and a plurality of friction elements that are selectively fastened to realize a plurality of shift speeds by switching a power transmission path of the gear mechanism. Operating state detecting means for detecting an operating state of the vehicle including a value relating to an engine load; and a detection result of the detecting means and at least a shift characteristic predetermined according to a value relating to a vehicle speed and a value relating to an engine load. An automatic transmission including target gear position setting means for setting a target gear position based on the target gear position, and control means for controlling an engagement state of the friction element such that a shift to the target gear position set by the setting means is performed. The control device according to claim 1, wherein when the value related to the vehicle speed detected by the driving state detecting means is equal to or more than a predetermined value, the target gear position setting means sets the last time. When a target gear of a gear that is at least two gears larger than the gear of the set target gear is set this time, a jump gear that prohibits a direct gear shift from the previously set target gear to the currently set target gear. A prohibition means is provided.

Further, the invention according to claim 4 (hereinafter referred to as "fourth invention") is provided by selectively connecting the torque converter and the speed change gear mechanism to each other to switch the power transmission path of the gear mechanism. Operating state detecting means for detecting a driving state of the vehicle, having a plurality of friction elements for realizing a plurality of speeds, and target speed setting means for setting a target speed based on a detection result of the detecting means; Control means for controlling the engagement state of the friction element so that the gear is shifted to the target shift speed set by the setting means. Among them, a friction element that is engaged only at the third or higher gear is included, and vehicle speed detecting means for detecting a value related to the vehicle speed is provided. When the target gear of the fourth or higher gear is set when the value related to the vehicle speed detected by the detection means is equal to or greater than a predetermined value, the previously set target gear is set. It is characterized in that an intermittent shift inhibiting means is provided for inhibiting a direct shift from the gear position to the currently set target gear position.

According to a fifth aspect of the present invention (hereinafter, referred to as a "fifth invention"), in any one of the first to fourth inventions, the shift to the previously set target shift speed is performed in the same manner. If the current target gear is set during a gear shift from a gear higher than the target gear, and the gear is shifted to the previously set target gear, the jump gear shift prohibition means sets the previously set gear. A direct shift from the set target gear to the target gear set this time is permitted.

By using the above means, each invention of the present application operates as follows.

According to the first aspect of the present invention, a value relating to the vehicle speed is detected by the vehicle speed detecting means, and when the detected value is larger than a predetermined value, the gear is larger than the previously set target gear by at least two gears. When the target shift speed is set this time by the target shift speed setting means, that is, when it is determined that the jump shift of the upshift should be performed, the target shift speed set this time from the previously set target shift speed is set. The shift directly to the gear, that is, the above-mentioned upshift jump shift is prohibited by the jump shift prohibition means.

That is, the factors that reduce the durability of the engagement-side friction element include the change amount of the turbine speed before and after the gear shift and the magnitude of the torque before and after the shift, as well as the input side that is integrally rotated after the engagement. The deviation of the rotational speed of the rotary element between the rotary element on the output side and the rotary element on the output side before the engagement, that is, the relative rotational speed between the rotary elements before the speed change is also a factor. For example, even when the transmission ratio is the same at the same second speed, the relative rotation speed between the input-side rotary element and the output-side rotary element is higher at a high vehicle speed than at a low vehicle speed. As a result, a greater load will be applied to the fastening-side friction element in order to integrate them into the same rotational speed,
This also affects the durability of the friction element.

Therefore, the first aspect of the present invention is to suppress the problem of a decrease in the durability of the engagement-side friction element by prohibiting the jump shift at a high vehicle speed, and to permit the jump shift at a low vehicle speed. In this case, even if the accelerator is depressed during the jump shift operation and the torque is generated as a result, the vehicle is at a low vehicle speed, so that a large load is not applied to the engagement-side friction element. Even at vehicle speed, when the throttle opening is equal to or less than a predetermined value, it is possible to more effectively suppress the problem of deterioration in durability of the engagement side friction element as compared with the conventional technology that allows jump jumps uniformly. Become.

In this case, according to the second invention, in particular, when a value relating to the engine load is detected by the engine load detecting means and at least one of the detected value and the value relating to the vehicle speed is equal to or more than a predetermined value, When it is determined that the upshift jump speed should be performed, the upshift jump speed is prohibited by the jump speed shift inhibiting means.

Thus, when the torque is generated when the throttle opening is equal to or more than the predetermined value, when the vehicle speed is the predetermined value and the relative rotation speed is large, when any of the relative speeds is equal to or more than the predetermined value, or when both are equal to or more than the predetermined value. In this case, jump shifting is prohibited, and together with these prohibition conditions, it is possible to more effectively suppress the problem of reduction in durability of the engagement-side friction element.

According to the third aspect of the present invention, it is determined whether or not the value relating to the vehicle speed is equal to or greater than a predetermined value from the detection result of the driving state detecting means for detecting the driving state for setting the target gear position. Therefore, it is not necessary to newly provide a means for detecting a value relating to the vehicle speed for determining whether to permit or prohibit the jump shift.

On the other hand, according to the fourth invention, in particular, for example, 2
A -4 upshift jump shift, a 2-5 upshift jump shift, and the like are prohibited at a high vehicle speed, thereby suppressing a problem of a decrease in durability of a friction element that is engaged only in a third or higher gear. Will be.

According to the fifth aspect of the invention, in particular, when the jump shift of the upshift is the second shift in the multiplex shift generated during the first downshift, the upshift is exceptionally made. Shift jumping is permitted. Such multiple shifts occur, for example, when the driver once requests acceleration and depresses the accelerator pedal, but immediately stops and depresses the accelerator pedal. Accordingly, in such a case, if the first downshift is completed, the driver may reduce or cancel the depression of the accelerator pedal, and the emblem or the engine speed may increase, causing a sense of incongruity. Therefore, in such a case, the process immediately shifts to the second upshift jump shift even during the first downshift.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in terms of a mechanical configuration, a hydraulic control circuit, and a control operation.

Mechanical Configuration First, the overall mechanical schematic configuration of the automatic transmission 10 according to the present embodiment will be described with reference to the skeleton diagram of FIG.

The automatic transmission 10 includes, as main components, a torque converter 20, first and second planetary gear mechanisms 30 and 40 disposed adjacent to each other as a transmission gear mechanism driven by the output of the converter 20. A plurality of friction elements 51 to 55 such as clutches and brakes for switching the power transmission path formed by these planetary gear mechanisms 30 and 40 and a one-way clutch 56 are provided. Third to third speeds and first and second speeds in the L range, and reverse speed in the R range are obtained.

The torque converter 20 includes a pump 2 fixed in a case 21 connected to the engine output shaft 1.
2 and the pump 22
And a stator 25 interposed between the pump 22 and the turbine 23 and supported by the transmission case 11 via a one-way clutch 24 to increase the torque. And a lock-up clutch 26 provided between the case 21 and the turbine 23 and directly connecting the engine output shaft 1 and the turbine 23 via the case 21. And
The rotation of the turbine 23 is output to the planetary gear mechanisms 30 and 40 via a turbine shaft 27.

Here, an oil pump 12 driven by the engine output shaft 1 through a case 21 of the torque converter 20 is provided on the side opposite to the engine of the torque converter 20.
Is arranged.

On the other hand, the first and second planetary gear mechanisms 30,
Reference numeral 40 denotes sun gears 31 and 41, and a plurality of pinions 32 ... 32 meshed with the sun gears 31 and 41.
42 ... 42 and these pinions 32 ... 32, 42 ... 4
2 and pinion carriers 33, 43, and ring gears 34 meshed with the pinions 32,.
44.

Then, the turbine shaft 27 and the first
A forward clutch 51 is provided between the planetary gear mechanism 30 and the sun gear 31, a reverse clutch 52 is provided between the turbine shaft 27 and the sun gear 41 of the second planetary gear mechanism 40, and a turbine shaft 27 is provided with the second planetary gear mechanism. A 3-4 clutch 53 is interposed between the pinion carrier 43 and the pinion carrier 40, and a 2-4 brake 54 for fixing the sun gear 41 of the second planetary gear mechanism 40 is provided.

Further, the ring gear 34 of the first planetary gear mechanism 30 and the pinion carrier 43 of the second planetary gear mechanism 40
The low reverse brake 55 and the one-way clutch 56 are arranged in parallel between the transmission case 11 and these components, and the pinion carrier 33 of the first planetary gear mechanism 30 and the second planetary gear mechanism Forty ring gears 44 are connected, and the output gear 13 is connected to them.

The output gear 13 is meshed with a first intermediate gear 62 on an idle shaft 61 constituting an intermediate transmission mechanism 60, and the second intermediate gear 63 on the idle shaft 61 and a differential gear. The input gear 71 of the differential gear 70 meshes with the rotation of the output gear 13 and is input to the differential case 72 of the differential 70.
The left and right axles 73, 74 are driven via the zero.

Here, the relationship between the operating state of the friction elements 51 to 55 such as the clutches and brakes and the one-way clutch 56 and the shift speed is summarized in Table 1 below.

The automatic transmission 10 shown in the above skeleton diagram
2 is specifically configured as shown in FIG. 2. As shown in FIG. 2, the transmission case 11 is provided with a turbine rotation sensor 305 used for control described later. ing.

[0035]

[Table 1] Hydraulic Control Circuit Next, the configuration of a hydraulic control circuit for supplying and discharging operating pressure to and from hydraulic chambers provided in the friction elements 51 to 55 shown in FIGS. 1 and 2 will be described with reference to FIG.

Of the above frictional elements, the 2-4 brake 54 composed of a band brake has a fastening chamber 54a and a release chamber 54b as hydraulic chambers to which the operating pressure is supplied, and operates only in the fastening chamber 54a. When pressure is supplied,
-4 When the brake 54 is engaged and operating pressure is supplied only to the release chamber 54b, when operating pressure is not supplied to both chambers 54a and 54b, and when operating pressure is supplied to both chambers 54a and 54b. When 2-4 brake 54
Is to be released. The other friction elements 51 to 53, 55 have a single hydraulic chamber, and the friction elements are fastened when the hydraulic chamber is supplied with the operating pressure.

As shown in FIG. 3, the hydraulic control circuit 10
0, the main components are: a regulator valve 101 for adjusting the discharge pressure of the oil pump 12 to generate a predetermined line pressure; a manual valve 102 for switching the range by manual operation; Reverse valve 103, bypass valve 104, and 3-4 for switching oil passages leading to friction elements 51-55
A shift valve 105, a lock-up control valve 106, first and second ON-OFF solenoid valves (hereinafter referred to as "first and second SV") 111 and 112 for operating these valves 103 to 106, and Solenoid relay valve (hereinafter referred to as “relay valve”) for switching the supply destination of the operating pressure from 1SV111
07, and first to third duty solenoid valves (hereinafter, referred to as “first to third DSVs”) that control generation, adjustment, discharge, and the like of the operating pressure supplied to the hydraulic chambers of the friction elements 51 to 55.
121, 122, 123, etc. are provided.

Here, the first and second SVs 111, 11
Each of the second and first to third DSVs 121 to 123 is a three-way valve, and can obtain a state in which the upper and downstream oil paths are communicated and a state in which the downstream oil path is drained. ing. In the latter case, the oil passage on the upstream side is shut off, so that the operating oil from the upstream side is not drained out in a drain state, and the drive loss of the oil pump 12 is reduced.

Note that the first and second SVs 111 and 112 are O
At the time of N, the upper and downstream oil passages are communicated. Also, the first
When the third DSVs 121 to 123 are OFF, that is, when the duty ratio (the ratio of the ON time in one ON-OFF cycle) is 0%, the third DSVs 121 to 123 are fully opened to completely communicate the upper and downstream oil passages, and When the duty ratio is 10
At 0%, the oil path on the upstream side is shut off to cause the oil path on the downstream side to be in a drain state. At an intermediate duty ratio, the hydraulic pressure on the upstream side is used as the original pressure, and the duty ratio on the downstream side is reduced. An oil pressure adjusted to a corresponding value is generated.

The line pressure generated by the regulator valve 101 is supplied to the manual valve 102 via a main line 200, and is supplied to a solenoid reducing valve (hereinafter referred to as "reducing valve") 108. It is supplied to the 3-4 shift valve 105.

The line pressure supplied to the reducing valve 108 is reduced by the valve 108 to a constant pressure, and then supplied to the first and second SVs 111 and 112 via lines 201 and 202. .

This constant pressure is supplied to the relay valve 107 via the line 203 when the first SV 111 is ON, and when the spool of the relay valve 107 is located on the right side in the drawing (hereinafter the same). Is
Further, a pilot pressure is supplied to a control port at one end of the bypass valve 104 via the line 204 to urge the spool of the bypass valve 104 to the left. When the spool of the relay valve 107 is located on the left side, the 3-4 shift valve 105
Is supplied as pilot pressure to the control port at one end of
The spool of the 3-4 shift valve 105 is biased to the right.

When the second SV 112 is ON,
The constant pressure from the reducing valve 108 is supplied to the bypass valve 104 via a line 206, and when the spool of the bypass valve 104 is located on the right side, a lock-up control valve is further provided via a line 207. The control valve 106 is supplied as pilot pressure to a control port at one end of the control valve 106.
Bias the spool to the left. Also, bypass valve 1
When the spool No. 04 is located on the left side, the line 208
Is supplied as pilot pressure to the control port at one end of the low reverse valve 103 to urge the spool of the low reverse valve 103 to the left.

Further, the constant pressure from the reducing valve 108 is also supplied to the control port 101a of the regulator valve 101 via the line 209. In this case, the constant pressure is adjusted by the linear solenoid valve 131 provided on the line 209 according to, for example, the throttle opening of the engine. Therefore, the line pressure is adjusted by the regulator valve 101 according to the throttle opening and the like. Will be adjusted.

The main line 200 led to the 3-4 shift valve 105 is connected to the first line via the line 210 when the spool of the valve 105 is located on the right side.
The accumulator 141 communicates with the accumulator 141.
To introduce line pressure.

On the other hand, the line pressure supplied from the main line 200 to the manual valve 102 is D, S, L
Are introduced into the first output line 211 and the second output line 212 in each forward range, into the first output line 211 and the third output line 213 in the R range, and into the third output line 213 in the N range.

The first output line 211 is connected to the first output line 211.
It is led to the DSV 121 and supplies the first DSV 121 with a line pressure as a control source pressure. The downstream side of the first DSV 121 is connected to a low reverse valve 1 via a line 214.
03, and when the spool of the valve 103 is located on the right side, a further line (servo apply line)
It is guided to the engagement chamber 54a of the 2-4 brake 54 via 215. When the spool of the low reverse valve 103 is located on the left side, the spool is further guided to the hydraulic chamber of the low reverse brake 55 via a line (low reverse brake line) 216. Here, the line 21
A line 217 is branched from 4 and led to the second accumulator 142.

The second output line 212 is connected to the second output line 212.
The line pressure is supplied to the DSV 122 and the third DSV 123, the line pressure is supplied to these DSVs 122 and 123 as the control source pressure, and the line pressure is also supplied to the 3-4 shift valve 105.

The line 212 led to the 3-4 shift valve 105 is led to the lock-up control valve 106 via the line 218 when the spool of the valve 105 is located on the left side. Is located on the left side, and is further led to the hydraulic chamber of the forward clutch 51 via a line (forward clutch line) 219.

Here, the forward clutch line 2
The line 220 branched from 19 is led to the 3-4 shift valve 105. When the spool of the valve 105 is located on the left side, the line 220 communicates with the first accumulator 141 via the aforementioned line 210, and the valve 105 When the spool is located on the right side, it communicates with the release chamber 54b of the 2-4 brake 54 via the line (servo release line) 221.

The downstream side of the second DSV 122 to which the control source pressure is supplied from the second output line 212 is connected to a line 22.
The pilot pressure is supplied to the control port at one end of the relay valve 107 via the control port 2 to supply the pilot pressure to the port, thereby urging the spool of the relay valve 107 to the left. The line 22 branched from the line 222
3 is led to a low reverse valve 103, and the valve 10
When spool 3 is on the right, line 2
Leads to 24.

From this line 224, the orifice 15
1, the line 225 is branched, and the branched line 225 is led to the 3-4 shift valve 105. When the spool of the 3-4 shift valve 105 is located on the left side, the servo Release line 221
Through the release chamber 54b of the 2-4 brake 54.

Also, the orifice 1
A line 226 is further branched from a line 225 branched through the line 51, and the line 226 is further branched.
Is guided to the bypass valve 104, and is guided to the hydraulic chamber of the 3-4 clutch 53 via the line (3-4 clutch line) 227 when the spool of the valve 104 is located on the right side.

Further, the line 224 is directly led to the bypass valve 104, and communicates with the line 225 via the line 226 when the spool of the valve 104 is located on the left side. That is, the line 224 and the line 225
Are connected to bypass the orifice 151.

The downstream side of the third DSV 123 to which the control source pressure is supplied from the second output line 212 is connected to the line 22.
8 and is led to the lock-up control valve 106, and when the spool of the valve 106 is located on the right side, it communicates with the forward clutch line 219.
When the spool of the lock-up control valve 106 is located on the left side, it communicates with the front chamber 26a of the lock-up clutch 26 via the line 229.

Further, a third output line 213 from the manual valve 102 is led to the low reverse valve 103 to supply a line pressure to the valve 103. When the spool of the valve 103 is located on the left side, it is guided to the hydraulic chamber of the reverse clutch 52 via a line (reverse clutch line) 230.

The line 231 branched from the third output line 213 is led to the bypass valve 104, and when the spool of the valve 104 is located on the right side, the control of the low reverse valve 103 via the line 208 described above. The line pressure is supplied to the port as the pilot pressure, and the spool of the low reverse valve 103 is urged to the left.

In addition to the above configuration, the hydraulic control circuit 1
00 is provided with a converter relief valve 109. This valve 109 is a regulator valve 10
After the working pressure supplied from 1 through the line 232 is regulated to a constant pressure, this constant pressure is supplied to the lock-up control valve 106 via the line 233. This constant pressure is applied to the lock-up control valve 1
When the spool of the valve 106 is located on the right side, it is supplied to the front chamber 26a of the lock-up clutch 26 via the aforementioned line 229. When the spool of the valve 106 is located on the left side, the constant pressure is applied to the line 234. The air is supplied to the rear chamber 26b via the rear chamber 26b.

The lock-up clutch 26 is released when the constant pressure is supplied to the front chamber 26a, and the spool of the lock-up control valve 106 is located on the left side. When the pressure is supplied to the front chamber 26a,
The slip state is controlled according to the operating pressure.

From the manual valve 102, a line 235 leading to the main line 200 in each of D, S, L, and N ranges is led, and the regulator valve 1
01 is connected to the pressure reducing port 101b, and the line pressure is introduced into the pressure reducing port 101b in each of the above ranges. Has become lower.

Now, the specific structure of the hydraulic actuator of the 2-4 brake 54 will be described. As shown in FIG. 4, the hydraulic actuator comprises a transmission case 11 and a cover member 54c fixed to the case 11. The piston 54e is fitted into the servo cylinder 54d composed of the above, and the above-described fastening chamber 54a and release chamber 54b are formed on both sides thereof. In addition, the piston 54e
Has a band fastening stem 54f attached thereto, the stem 54f is engaged with one end of a brake band 54g wound around a member to be braked (not shown), and the other end of the band 54g. The side is engaged with a fixing stem 54h provided in the case 11, and a piston 54e is further provided in the release chamber 54b.
A spring 54i that urges toward the 4a side, that is, the side on which the brake band 54g is loosened, is housed.

An operating pressure is supplied from a control valve unit constituting the hydraulic control circuit 100 to the fastening chamber 54a and the release chamber 54b through an oil hole (not shown). By tightening or loosening the 54 g, the 2-4 brake 54 is engaged or released, and in particular,
In this hydraulic actuator, the piston 54
e, the pressure receiving areas on the fastening chamber 54a side and the release chamber 54b side are made substantially equal, and therefore, for example, both chambers 54a, 54
When an operating pressure equal to b is supplied, these pressures cancel each other and only the biasing force of the spring 54i acts on the release side.

On the other hand, as shown in FIG. 5, the automatic transmission 10 has the first and second
SV111, 112, first to third DSVs 121 to 123
And a control unit 300 for controlling the linear solenoid valve 131. The control unit 300 includes a vehicle speed sensor 301 for detecting the vehicle speed of the vehicle, a throttle opening sensor 302 for detecting the throttle opening of the engine, An engine rotation sensor 303 for detecting an engine speed, a shift position sensor 304 for detecting a shift position (range) selected by a driver, a turbine 23 in the torque converter 20
Signals from a turbine rotation sensor 305 for detecting the rotation speed of the engine, an oil temperature sensor 306 for detecting the oil temperature of the working oil, and the like are input, and the operating state of the vehicle or engine indicated by the signals from these sensors 301 to 306 Solenoid valves 111, 112, 121-123, 13
1 is controlled. FIG. 2 shows the turbine rotation sensor 305 in an attached state.

Next, the first and second SVs 111, 112
The relationship between the operating states of the first to third DSVs 121 to 123 and the supply and discharge states of the operating pressure of the friction elements 51 to 55 to and from the hydraulic chamber will be described for each shift speed.

Here, the combinations (solenoid patterns) of the operating states of the first and second SVs 111 and 112 and the first to third DSVs 121 to 123 for each gear are set as shown in Table 2 below.

In Table 2, (○) indicates the first and second SV1.
ON for 11 and 112, 1st to 3rd DSV 121
Reference numerals 123 to 123 are OFF, and all indicate a state in which the upstream oil passage is communicated with the downstream oil passage and the original pressure is supplied to the downstream as it is. (×) indicates the first and second
OFF for SV111 and 112, 1st to 3rd DS
V121 to V123 are ON.
This shows a state in which the upstream oil passage is shut off and the downstream oil passage is drained.

[0067]

[Table 2] First, in the first gear (excluding the first gear in the L range),
As shown in FIG. 6, only the third DSV 123 operates to generate an operating pressure using the line pressure from the second output line 212 as a source pressure, and this operating pressure is supplied via a line 228 to a lock-up control valve. 106. At this point, the spool of the lock-up control valve 106 is located on the right side,
The operating pressure further increases the forward clutch line 219
Is supplied to the hydraulic chamber of the forward clutch 51 as a forward clutch pressure, whereby the forward clutch 51 is engaged.

Here, the forward clutch line 2
19 is connected to the first accumulator 1 via the 3-4 shift valve 105 and the line 210.
Due to the communication with 41, the supply of the forward clutch pressure is performed gently.

Next, in the second speed state, as shown in Table 2 and FIG. 7, in addition to the first speed state, the first DSV 12
1 also operates, and generates an operating pressure using the line pressure from the first output line 211 as a source pressure. This operating pressure is
4 to the low reverse valve 103,
At this time, since the spool of the low reverse valve 103 is located on the right side, it is further introduced into the servo release line 215, and the engagement chamber 54 of the 2-4 brake 54
a is supplied as servo apply pressure. This allows
In addition to the forward clutch 51, a 2-4 brake 54 is engaged.

Since the line 214 communicates with the second accumulator 142 via the line 217, the supply of the servo apply pressure or the application of the 2-4 brake 54 is performed gently. When the spool of the low reverse valve 103 moves to the left when shifting to the first speed in the L range, which will be described later, the hydraulic oil stored in the accumulator 142 is transmitted from the low reverse brake line 216 to the hydraulic pressure of the low reverse brake 55. The room is precharged.

In the state of the third speed, as shown in Table 2 and FIG. 8, in addition to the state of the second speed, the second DS
V122 also operates, and generates an operating pressure using the line pressure from the second output line 212 as a source pressure. This operating pressure is supplied to the low reverse valve 103 via the line 222 and the line 223. At this time, since the spool of the valve 103 is located on the right side, the line 2
24.

This operating pressure is introduced from the line 224 to the line 225 via the orifice 151,
At this point, since the spool of the 3-4 shift valve 105 is located on the left side, the servo is further moved to the release chamber 54b of the 2-4 brake 54 via the servo release line 221. Supplied as release pressure. Thereby, 2-4 brake 5
4 is released.

Further, the orifice 1
From line 225 branched through 51, line 22
6 is branched, and the operating pressure is guided to the bypass valve 104 by the line 226. At this time, the spool of the bypass valve 104 is located on the right side, and further, via the 3-4 clutch line 227. The pressure is supplied to the hydraulic chamber of the 3-4 clutch 53 as a 3-4 clutch pressure. Therefore, in the third speed, the forward clutch 51 and the 3-4 clutch 53 are engaged, while the 2-4 brake 54 is released.

In the third speed, the second DSV 122 generates the operating pressure as described above,
The spool of the relay valve 107 is moved to the left by being supplied to the control port 107a of the relay valve 107 via 2.

Further, in the fourth speed state, as shown in Table 2 and FIG. 9, the third DSV 123 stops generating the operating pressure and the first SV 111 operates in the third speed state.

The operation of the first SV 111 causes a constant pressure from the line 201 to be supplied to the relay valve 107 via the line 203. As described above, the spool of the relay valve 107 moves to the left at the third speed. , The constant pressure is
This is supplied to the control port 105a of the four-shift valve 105, and the spool of the valve 105 moves to the right. Therefore, the servo release line 221 is divided into the line 22 branched from the forward clutch line 219.
0, and the release chamber 54b of the 2-4 brake 54 communicates with the hydraulic chamber of the forward clutch 51.

Then, as described above, the third DSV 123 stops generating the operating pressure and sets the downstream side to the drain state, whereby the servo release pressure in the release chamber 54b of the 2-4 brake 54 and the forward clutch 51 Of the third DSV via the lock-up control valve 106 and the line 228.
It will be drained at 123.
The brake 54 is engaged again, and the forward clutch 51 is released.

On the other hand, in the first speed of the L range, Table 2 and FIG.
As shown in FIG. 0, the first and second SVs 111 and 112 and the first and third DSVs 121 and 123 operate and the third DSVs 121 and 123 operate.
The operating pressure generated by V123 is 1 such as D range.
Similarly to the speed, the hydraulic pressure is supplied to the hydraulic chamber of the forward clutch 51 via the line 228, the lock-up control valve 106, and the forward clutch line 219 as the forward clutch pressure, and the forward clutch 51 is engaged. At this time, the operating pressure is introduced into the first accumulator 141 through the line 220, the 3-4 shift valve 105 and the line 210, so that the forward clutch 51 is loosely engaged. The points are the same as those of the first speed such as the D range.

Further, by the operation of the first SV 111, pilot pressure is supplied to the control port 104a of the bypass valve 104 via the line 203, the relay valve 107, and the line 204, and the spool of the valve 104 is moved to the left. Accordingly, the operating pressure from the second SV 112 is reduced by the line 206 and the bypass valve 104.
And is supplied to the control port 103a of the low reverse valve 103 to move the spool of the low reverse valve 103 to the left.

Accordingly, the operating pressure generated by the first DSV 121 is supplied as a low reverse brake pressure to the hydraulic chamber of the low reverse brake 55 via the line 214, the low reverse valve 103, and the low reverse brake line 216. The low reverse brake 55 is engaged in addition to the clutch 51, and the first speed at which the engine brake operates is obtained.

Further, in the R range, as shown in Table 2 and FIG. 11, the first and second SVs 111 and 112 and the first to
The third DSVs 121 to 123 operate. However, the second,
Regarding the third DSVs 122 and 123, the supply of the original pressure from the second output line 212 is stopped, so that no operating pressure is generated.

In this R range, the first,
Since the second SVs 111 and 112 are operated, the spool of the bypass valve 104 moves to the left and the spool of the low reverse valve 103 also moves to the left as in the case of the first speed in the L range. Then, in this state, the operating pressure is generated by the first DSV 121,
This is supplied to the hydraulic chamber of the low reverse brake 55 as a low reverse brake pressure.

On the other hand, in the R range, the manual valve 1
02, a line pressure is introduced into the third output line 213,
This line pressure is supplied as the reverse clutch pressure to the hydraulic chamber of the reverse clutch 52 via the low reverse valve 103 and the reverse clutch line 230 whose spool has moved to the left as described above. Therefore, the reverse clutch 52 and the low reverse brake 55 are engaged.

The third output line 213 has N
Since the line pressure is also introduced from the manual valve 102 in the range, when the spool of the low reverse valve 103 is located on the left side, the reverse clutch 52 is set in the N range.
Is concluded.

Control Operation Next, a specific control operation by the above-described control unit 300, in particular, a control operation for automatic shifting will be described.

Control for this automatic shift is performed according to the program shown in the flowcharts of FIGS. 12 and 13. After the type of shift is finally determined in step S29, the determination is made in the next step S30. Type shift control, that is, the operation of the first and second SVs 111 and 112 and the first to third DSVs 121 to 123 so as to release or engage the predetermined clutches and brakes 51 to 55 predetermined for each shift speed as described above. Control for switching the state is performed, whereby the automatic shift of the vehicle is achieved.

In this case, the type of shift is determined in step S29 based on the speed G0 before the speed change and the speed G after the speed change, that is, the target speed to be achieved after the speed change. , The speed G0 before shifting is 2nd speed,
If the target shift speed G is the third speed, the type of shift is determined to be 2-3 upshift.

By executing this automatic shift control program, the pre-shift speed G0 and the post-shift speed G are rewritten to various values in accordance with the operation state, respectively. When the values of the stages G0 and G are different from each other, the shift control from the pre-shift stage G0 to the post-shift stage G is performed.

In step S1, it is determined whether or not the shift control is being performed. If YES, proceed to step S3,
In the case of NO, the process proceeds to step S3 via step S2.

In step S2, the value of the post-shift speed G is substituted for the value of the pre-shift speed G0. Immediately after the shift is completed, the process proceeds to step S1 for the first time. If it is determined that the shift control is not being performed, and if the process proceeds to step S2, the value of the pre-shift speed is calculated from the value of the pre-shift speed in the completed shift. The value of the gear stage, that is, the value of the currently traveling gear stage, is rewritten, and while the vehicle is traveling at that gear stage until the next shift occurs, the value of the traveling gear stage continues to be the value of the pre-shift gear stage. Will be maintained.

In step S3, the target shift stage G1 is set based on the driving state represented by the vehicle speed and the throttle opening and a shift pattern map (shift characteristic) preset according to the driving state. Here, in the memory of the control unit 300, as shown in FIG. 14, the vehicle speed V and the throttle opening θ (engine load) are used as parameters in advance so that the higher the vehicle speed and the lower the load, the higher the gear position is selected. The target shift speed G1 is set by applying a signal relating to the vehicle speed from the vehicle speed sensor 301 and a signal relating to the throttle opening from the throttle opening sensor 302 to the map. You.

Note that the target gear stage G1 is a temporary one, and as will be described later, in the following steps, various processes are performed in accordance with the operating state, and further, the second and third temporary gear stages G2 and G2 are set. Through G3, a gear position to be finally achieved after the gear shift, that is, a gear shift target G is set.

In step S4, the values of various jump shifting inhibition flags F13, F24, F14, F42 and F31 are read. The value of the jump shift prohibition flag is shown in FIG.
5 is set to 0 or 1 by the setting program of the jump shift prohibition flag, and when 0, the jump shift is permitted, and when it is 1, it is prohibited. The target jump speed is 1-3 upshift, 2-4 upshift, 1
-4 upshift, 4-2 downshift, and 3-1 downshift.

As shown in steps S101 to S103, the upshift 1-3 jump shift prohibition flag F13 is set to 0 when the shift stage is in the first speed, and the timer value T10 counted up when the shift stage is other than the first speed. When the value is smaller than the predetermined timer value C13 and the throttle opening θ is larger than the predetermined throttle opening TVO13, the value becomes 1
, Otherwise set to zero.

That is, when at least the first gear is the first speed, and the driver requests acceleration and the accelerator pedal is depressed to a large extent and the engine load is large, the jump shift to the third speed is prohibited, and A 1-2 shift is performed. Then, at a point in time when a predetermined time C13 has elapsed since the 1-2 shift has been performed and the shift speed has shifted from the first speed to the second speed,
The value of the 1-3 jump shift prohibition flag is set to 0, and the shift to the third speed is permitted. Here, the predetermined timer value C13 is set to a slightly longer time, for example, about 2 seconds. This is because, in the case of an upshift, it is more preferable in terms of feeling that the next shift occurs after one shift is completed and calms down for a while, than when the shift continuously occurs with little time. The prohibition of such a 1-3 jump shift is mainly to avoid a decrease in the durability of the friction element.

Similarly, the upshift 2-4 jump speed change inhibition flag F24 is also set in steps S104 to S106.
As shown in the figure, the value T20 of the timer that is counted up when the gear is 2nd speed and is not 1st gear is less than the predetermined timer value C24, and the throttle opening θ is the predetermined throttle opening. When it is greater than TVO 24, its value is set to 1, otherwise it is set to 0.

That is, when at least the second speed is the second speed, and the driver demands acceleration and the amount of depression of the accelerator pedal is large and the engine load is large, the jump shift to the fourth speed is prohibited, and A 2-3 shift is performed. When a predetermined time C24 elapses after the 2-3 shift is performed and the shift speed shifts from the second speed to the third speed,
The value of the 2-4 jump shift prohibition flag is set to 0, and the shift to the fourth speed is permitted. Here, the predetermined timer value C24 is, for example, 2 from the viewpoint of the shift feeling.
It is set to a slightly longer time of about seconds. The prohibition of such a 2-4 jump shift is mainly due to
This is to avoid a decrease in the durability of the friction element.

Similarly, the upshift 1-4 jump shift inhibition flag F14 is set in steps S107 to S109.
As shown in the figure, when the above-mentioned timer value T10, which is counted up when the shift speed is the first speed and is not the first speed, is less than a predetermined timer value C14, the value is set to 1, Otherwise, it is set to 0.

That is, when at least the first speed is the first speed, the intermittent shift to the fourth speed is prohibited.
The 1-2 shift or the 1-3 jump jump is performed depending on the value of. When a predetermined time C14 elapses after the 1-2 shift or the 1-3 jump shift is performed and the shift speed shifts from the first speed to the second speed or the third speed, the 1-4 jump shift disable flag is set. The value is set to 0, and further, by the value of the above-described 2-4 jump shift inhibition flag F24,
Shifting to the third or fourth speed is permitted. Here, the predetermined timer value C14 is also set to a slightly longer time, for example, about 2 seconds from the viewpoint of the shift feeling.

It should be noted that, with respect to the 1-4 jump shift, unlike the above 1-3 jump shift or 2-4 jump shift, the throttle opening is not a determination condition. That is, 1-4 jump shifts are prohibited at all times during the predetermined time C14 after the first speed or the exit of the first speed. This is because the timing of releasing the forward clutch 51 and the timing of
This is because the timing for engaging the -4 clutch 53 cannot be properly established.

As shown in steps S110 to S112, the downshift 4-2 jump shift prohibition flag F42 indicates that the throttle opening is fully closed, the vehicle speed V is less than the predetermined vehicle speed V42, and the current gear ratio Is smaller than the gear ratio at the time of the third speed, that is, the value of the timer T40, which is 0 when the fourth gear is not yet completed and counts up when the gear is other than the fourth gear, is predetermined. Is less than the timer value C42, the value is set to 1; otherwise, it is set to 0. Here, the predetermined timer value C42 is used as a backup for releasing the prohibition of the 4-2 jump shift relatively early, for example, from 0.
It is set to a very short time of about 2 seconds.

That is, for example, when the shift position is switched from the D range to the L range in a manual downshift, the 3-2 shift is performed within a relatively short time after the 4-3 shift is completed. It happens continuously,
A large engine brake can be obtained early.
It should be noted that such a 4-2 jump shift is also prohibited.
This is mainly to avoid a decrease in the durability of the friction element.

Similarly, the downshift 3-1 jump shift prohibition flag F31 is determined in steps S113 through S115.
As shown in the figure, the throttle opening is fully closed, the vehicle speed V is lower than the predetermined vehicle speed V31, and the current gear ratio is 2
The value T30 of the timer which is less than the gear ratio at the time of the speed, that is, the timer value T30 that is 0 when the gear is 3rd and has not been completed yet and is counted up when the gear is other than 3rd is a predetermined timer When the value is less than C31, the value is set to 1,
Otherwise, it is set to zero. Here, the predetermined timer value C31 is also set to a very short time of about 0.2 seconds, for example, as a backup for canceling the inhibition of the 3-1 jump shift relatively early.

That is, for example, when the shift position is switched from the S range to the L range in a manual downshift, the 2-1 shift is performed within a relatively short time after the completion of the 3-2 shift. It happens continuously,
A large engine brake can be obtained early.
It should be noted that such a 3-1 jump shift is also prohibited.
This is mainly to avoid a decrease in the durability of the friction element.

Returning to the control program for automatic shifting,
In steps S5 to S11, the target gear G1
And the jump shift prohibition flags F13, F24, F14, F
The second provisional gear stage G2 is set from the values of 42 and F31.

In step S5, as the determination of the upshift direction, the first provisional gear G1 is set to the fourth speed and 1-3
It is determined whether the jump shift prohibition flag F13 is 0, the 2-4 jump shift inhibition flag F24 is 0, and the 1-4 jump shift inhibition flag F14 is 0. If YES, the second temporary shift inhibition flag F14 is determined in step S6. The shift stage G2 is set to the fourth speed, and if NO, the process proceeds to step S7.

In step S7, as the determination of the upshift direction, the first provisional speed G1 is set to the third gear or higher,
-3 whether or not the jump shift prohibition flag F13 is 0;
Alternatively, as the determination of the downshift direction, it is determined whether or not the first provisional shift speed G1 is the second speed or lower and the 4-2 jump shift prohibition flag F42 is 1, and if YES, the process proceeds to step S8. The second provisional speed stage G2 is set to the third speed,
In the case of NO, the process proceeds to step S9.

In step S9, as a determination in the upshift direction, it is determined whether or not the first temporary gear G1 is in the second speed or higher, or as a determination in the downshift direction, the first temporary gear G1 is in the first gear. Then, it is determined whether or not the 3-1 jump shift prohibition flag F31 is 1; if YES, the second provisional gear stage G2 is set to the second speed in step S10; if NO, step S11 Is set to 1st speed.

In step S12, it is determined whether or not the value T1 of the timer counted up from the start of the shift control at 0 when the shift control is not being performed is larger than a predetermined timer value C1, and YES. If step S
At 13, the value of the re-shift prohibition flag F50 is set to 1, and
If NO, it is set to 0 in step S14.

Here, the above-mentioned predetermined timer value C1 is set such that, when the shift control to the previously set target shift speed is started, if a target shift speed different from the target shift speed is set later, the shift speed is changed. This is an index for determining whether or not to shift the control to the shift control to the target shift speed set thereafter, from the start of the shift control experimentally obtained in advance to the actual start of the shift operation. Is set to a time slightly shorter than the time, for example, about 0.2 to 0.3 seconds. Then, after the value of the re-shift prohibition flag F50 is set to 1, since the shift operation to the previously set target shift speed has actually started, it is determined that the multiple shift is performed. Thereafter, in principle, the shift control from the previously set target shift speed to the shift control to the later set target shift speed is not shifted. However, when the shift to the previously set target shift speed is in the downshift direction and the later set target shift speed is higher than the target shift speed of the downshift, the re-shift prohibition flag F50 is set. Value is 1
, The shift control to the target shift speed set thereafter is immediately started.

In step S15, the driver depresses the accelerator pedal in the multiple shifts as described above. As a result, after the target shift speed in the downshift direction is set first, the driver releases the accelerator pedal. Is released, and as a result, it is determined whether or not the target shift speed in the upshift direction is set to overlap later.

That is, the determination conditions are that the throttle opening is fully closed, and that the pre-shift speed G0 is the same as the previously set target speed Ga (the post-shift speed set in the previous control cycle). G) and that the second provisional shift speed G2 (the provisional post-shift speed set so far in the current control cycle) is larger than the previously set target shift speed Ga. is there.

For example, during the shift control of the downshift from the fourth speed to the second speed, if the second provisional speed stage G2 is set to the third speed up to step S11, the pre-shift speed G0 is The fourth speed and the previously set target gear stage Ga are the second speed, so that this determination condition is satisfied.

Then, in the case of YES, step S16
After the value of the second provisional gear stage G2 is further set as the value of the third provisional gear stage G3, the next step S
At steps S17 and S18, a process of rewriting the value of the pre-shift speed G0 is performed.

This is because, for example, as in the above-described example, during the shift control from the 4th speed to the 2nd speed, the target shift speed of the 3rd speed is set and the shift to the shift control to the 3rd speed is performed. Depending on how far the shifting operation of the preceding 4-2 downshift has proceeded, the subsequent shifting is performed as 2-3 shifting, or
It is intended to determine whether the shift should be performed as a third shift, and to rationally execute a shift to the third target shift speed set thereafter. In that case, the progress of the preceding shift operation is detected by the turbine speed.

That is, in step S17, the turbine rotational speed Nta at the time when the temporary gear stage G3 set so far is achieved in the current control cycle is calculated, and in step S18, the third temporary gear shift is performed. Whether the value of the speed G3 is different from the value of the pre-shift speed G0, that is, the fourth speed (G0) -second speed instead of the fourth speed (G0) -second speed (Ga) -fourth speed (G3) (Ga) -3rd speed (G3) and the current turbine speed Nt
Is higher than the turbine speed Nta at the time when the provisional gear stage G3 is achieved, that is, the gear shifting operation to the previously set target gear stage Ga has been set so far in the current control cycle. It is determined whether or not the vehicle has moved beyond the provisional gear stage G3 to near the target gear stage Ga set ahead. Further, it is determined whether the pre-shift speed G0 is the fourth speed, the third provisional speed stage G3 is the fourth speed, and whether the previously set target speed Ga is the second speed.

Then, in the case of YES, step S19
Then, the value of the previously set target gear Ga is set as the value of the pre-shift gear G0. In contrast, N
In the case of O, the value of the pre-shift speed G0 is maintained as it is in the value of the pre-shift speed in the previous shift.

Thus, the fourth speed (G0) -second speed (Ga)
In the case of a shift such as -3rd speed (G3), the value of the pre-shift speed (G0) is not rewritten unless the preceding 4-2 shift has progressed so much. If the previous 4-2 shift is considerably advanced while the shift is performed as three shifts, the value of the pre-shift speed (G0) becomes equal to the value of the previous target shift speed (G
a), and as a result, the subsequent shift is 2-
It is performed as three shifts.

In the case of a third gear (G0) -second gear (Ga) -third gear (G3), regardless of the progress of the preceding 3-2 gear, the pre-shift gear (G0). Is not rewritten. As a result, the subsequent shift is always performed as the 3-3 shift, and not performed as the 2-3 shift. In contrast,
In the case of a speed change such as a fourth speed (G0) -second speed (Ga) -fourth speed (G3), the value of the pre-shift speed (G0) is changed regardless of the progress of the preceding 4-2 shift. The target gear (Ga) is rewritten to the value, and as a result, the subsequent shift is always performed as 2-4 shift, and not performed as 4-4 shift. These are because a shock occurs due to the configuration of the hydraulic control circuit 100.

Then, in the next step S20, the flag F
The value of 60 is set to one. This step S20 is
Since the process passes when the result of the determination in step S15 is YES, the current throttle opening is fully closed, and among the multiple shifts, particularly, after the target shift speed in the downshift direction is set first, Whether or not the target shift speed in the upshift direction later passed through the multiple shifts that were set in an overlapping manner, that is, whether the driver depressed the accelerator pedal but performed an operation to return the accelerator pedal to the original position in a short time The above-mentioned flag F60 indicates whether or not this is the case.

Returning to the determination at step S15, if NO, the process proceeds to step S21, where the pre-shift gear G0 is the second speed, the value of the flag F60 is 0, and the flag F70
Is determined whether or not the value of is 1. This flag F70
Is that the value of the 2-4 jump shift prohibition flag F24 is 0
This indicates whether the current vehicle speed is higher than the predetermined vehicle speed when the 2-4 jump speed is permitted, and the value is 1 when the current vehicle speed is higher than the predetermined vehicle speed.
And set to 0 if low.

Then, if "YES" is determined in the step S22.
Then, the third speed is set as the value of the third provisional gear stage G3.
That is, the value of the 2-4 jump shift prohibition flag F24 is 0.
Even in this case, the 2-4 jump shift is prohibited, and the third speed is set as the temporary target shift speed. In this case, the determination of YES in step S21 is based on the condition that the value of the flag F60 is 0 in step S20 in addition to the value of the flag F70 being 1 In the end, YE in step S15
When S has not been determined, that is, when the driver has depressed the accelerator pedal but has not performed an operation to return the accelerator pedal to the original position in a short time, the 2-4 jump shift is prohibited. The gears are sequentially shifted from second gear to third gear to fourth gear.

On the other hand, if NO in step S21, the flow advances to step S23. From step S21 to step S
The process proceeds to step S23 when the value of the flag F60 is 1, that is, the driver has depressed the accelerator pedal but performed an operation to return the accelerator pedal to the original position in a short time. This includes the case where YES has been determined.

Then, in step S23, it is determined whether or not the value of the re-shift prohibition flag F50 is 0. In the case of YES, the routine proceeds to step S24, in which the second temporary gear G
2 is set as the value of the third provisional gear stage G3, and NO
In such a case, the value of the third provisional gear stage G3 is not updated. That is, the previous value of the third provisional gear stage G3 is maintained as it is.

The above steps S20 and S20
22 and step S23 or S24, respectively, to step S25. In this step S25, again
It is determined whether or not shift control is being performed. If YES, the process directly proceeds to step S27, and if NO, the process proceeds to step S27.
In step 26, the value of the flag F60 is set to 0, and the process proceeds to step S27.

In step S27, it is determined whether or not the engagement control is being performed.
At 28, the value of the third provisional shift speed G3 is finally determined as the value of the post-shift speed G, that is, the target shift speed to be achieved after the shift, and then the process proceeds to step S29. If YES, the process proceeds to step S29.
The process directly proceeds to step S29 without passing through. That is, during the engagement control such as ND, the value of the post-shift gear stage G is not updated, and the current gear stage is maintained.

Then, in step S29, the type of shift is determined from the shift stage G0 before shift and the shift stage G after shift, and in the next step S30, shift control of the determined type is performed, and the shift target is determined. The automatic transmission to is achieved.

As described above, the driver depresses the accelerator pedal, but performs an operation of returning the accelerator pedal to the original position in a short time. As a result, the gear shift such as the fourth, second, and fourth speed is performed. In this case, the values of the pre-shift gear stage G0 and the post-shift gear stage G are rewritten as follows.

First, before the accelerator pedal is depressed, while traveling at the fourth speed, the vehicle travels from step S1 to step S2.
Here, the shift stage G0 before the shift is set to the fourth speed, and the temporary shift stage G2 is set to the fourth speed through steps S3 to S6. Next, after steps S12 to S14 are performed and the re-shift prohibition flag F50 is set to 0, the process proceeds to step S15.
After S21 and S23, the provisional gear stage G3 is determined in step S24.
Is the fourth speed. Then, via steps S25 to S26, and via steps S27 to S28,
Here, the post-shift gear stage G is set to the fourth speed, and in the end, in steps S29 and S30, the fourth speed which is the current traveling gear stage is maintained.

Next, when the driver depresses the accelerator pedal, the process goes from step S1 to step S2, where the pre-shift speed G0 is set to the fourth speed, and the steps S3 to S3 are executed.
After S5 and S7, S9, S10, the provisional gear stage G2 becomes 2
It is assumed to be fast. In this case, the value of the 4-2 jump shift prohibition flag F42 is set to 0 because the determination condition of step S110 shown in FIG. 15 includes that the throttle opening is fully closed. Therefore, step S
Proceeding from S7 to S8, the temporary gear G2 is not set to the third speed.

Next, after steps S12 to S14 are performed, the re-shift prohibition flag F50 is set to 0.
After steps S15, S21 and S23, step S2
In step 4, the provisional gear stage G3 is set to the second speed. And step S
25 to S26, and from step S27 to S
28, the post-shift gear stage G is set to the second speed. After all, the 4-2 shift is determined in step S29, and the 4-2 shift control is executed in step S30.

Next, when the driver stops depressing the accelerator pedal and returns to the original position, the process proceeds directly from step S1 to step S3 because the 4-2 shift control is being performed. Therefore, the pre-shift gear stage G0 is maintained at the fourth speed. Next, through steps S4 to S6, the provisional gear stage G2 is set to the fourth speed. In this case, the 2-4 jump shift prohibition flag F2
The value of 4 is set to 0 since the determination condition of step S104 shown in FIG. 15 includes that the throttle opening θ is larger than the predetermined value TVO24. Therefore, the process proceeds from step S5 to S7 and S8, where the provisional gear stage G
2 will not be in 3rd gear.

Then, from step S12 to S13 or S
14, the re-shift prohibition flag F50 is set to 1 or 0, and YES is determined in step S15. Then, in step S16, the temporary gear stage G3 is set to 4
After the speed is increased, the flow goes through step S17 to step S1.
In the case of No. 8, YES is determined because G0 = 4th speed, G3 = 4th speed, and Ga = 2nd speed. As a result, G0 is rewritten from the fourth speed to the second speed in step S19, and
After the flag 60 is set to 1 in step S20,
After the steps S25 and S27, the gear G after the shift is set to the fourth speed in the step S28.
In step S30, 2-4 shift control is executed.

That is, in this case, the shift from the 4-2 shift control to the 2-4 shift control is performed regardless of the value of the re-shift inhibition flag F50 set in steps S12 to S14. It is possible to avoid the problem of a great discomfort for the driver such as excessive engine braking being applied or an increase in engine speed.

Further, under the condition that the throttle opening is fully closed, the engine rotation is reduced, and the output torque is also reduced, the 4-2 shift control is switched to the 2-4 shift control. Since the switching is performed, even if the timing of changing the friction element is shifted, the degree of engine blow-up in the neutral state is reduced, and the degree of shift shock is small.

Incidentally, after that, the provisional shift stage G2 is set to the fourth speed through steps S1 to S3 to S6, and then, after the re-shift prohibition flag is set to 0 or 1 in steps S12 to S14. In step S15, G0 =
Since the second speed and Ga = G2 = fourth speed do not correspond to the condition, the process proceeds to step S21. Here, since the flag F60 = 1 does not correspond to the condition, the process proceeds to step S23. If the result of the determination in step S23 is YES, the provisional gear stage G
The third gear is set to the fourth speed, and also in the case where the determination is NO, the fourth speed is eventually set because the previous provisional gear stage G3 is maintained. As a result, in any case via steps S25, S27, and S28, the current 2-4 shift control is continued in steps S29 and S30.

By the way, the shift pattern map shown in FIG. 14 generally has a hysteresis between the upshift direction and the downshift direction in order to prevent hunting. Accordingly, for example, as shown by reference numeral a in the figure, from the driving state at the position between the 3-4 upshift line and the 4-3 downshift line, the driver depresses the accelerator pedal, and When the vehicle shifts to the operating state at the position shown in the figure, and the second speed is selected, the accelerator pedal is returned again to return to the operating state at the position shown by the same reference numeral as above. Instead, the third speed will be selected. In other words, as a result, a downshift from the fourth speed to the third speed occurs, which also causes the driver to feel discomfort.

In this case, there is a problem that the operation state changes from the operation state indicated by the reference sign A to the operation state indicated by the reference sign A, and then returns to the operation state indicated by the same reference sign A again. This occurs when the driver releases the accelerator pedal for a short time after the setting and the start of the 4-2 shift control to the second speed. That is, this is a problem that can occur when NO is determined in step S12 and the flag F50 is 0 in step S14.

This problem is avoided by the determination in step S23. That is, in step S23, when the flag F50 is 0, the provisional gear stage G2 set in the current control cycle is not adopted, and
Since the previous provisional gear stage G3 is maintained, the fourth speed is finally set as the target gear stage G even in the above case.

FIG. 16 shows changes over time of main variables and flag values in the fourth-gear-second-gear shift control.

Next, the driver depresses the accelerator pedal but performs an operation to return the accelerator pedal to the original position in a short time. The case in which this is performed will be described. However, while the vehicle is traveling at the 4th speed before the accelerator pedal is depressed, and until the driver depresses the accelerator pedal and the 4-2 shift control is executed, the above-described case of the 4th to 2nd and 4th speeds is used. The description is omitted because it is the same.

When the driver stops pressing the accelerator pedal and returns to the original state during the 4-2 shift control, the process directly proceeds from step S1 to step S3 because the 4-2 shift control is being performed. Therefore, the pre-shift gear stage G0 is maintained at the fourth speed. Next, through steps S4, S5, S7, and S8, the provisional gear stage G2 is set to the third speed.

Next, from step S12 to S13 or S
14, the re-shift prohibition flag F50 is set to 1 or 0, and YES is determined in step S15. Then, in step S16, the provisional gear stage G3 becomes 3
After the speed is increased, the flow goes through step S17 to step S1.
8, G0 = 4th speed and G3 = 3rd speed, which are different from each other, so that the current turbine speed Nt is larger than the turbine speed Nta at the 3rd speed, and the 4-2 shift is considerably advanced. If so, G0 is rewritten from the fourth speed to the second speed in step S19, while the current turbine speed Nt is smaller than the turbine speed Nta at the third speed and the 4-2 shift is not progressing much. In this case, G0 is maintained at the fourth speed.

Then, in step S20, the flag 60 is set to 1
, And after step S25, S27, the post-shift gear stage G is set to the third speed in step S28,
Eventually, in step S29, when the preceding 4-2 shift is considerably advanced, the 2-3 shift is performed, while the previous 4 shift is performed.
-2 when the shift is not progressing much 4-3
The shift is determined, and in step S30, 2-3 shift control or 4-3 shift control is executed.

By performing such control, the shift control from the 4-2 shift control to the second speed previously set as the post-shift speed is changed to the shift control to the third speed set as the post-shift speed. The shift is performed rationally, and as a result, the third gear set later is smoothly and smoothly achieved.

Next, while the driver is depressing the accelerator pedal and driving at the second speed, the driver suddenly stops the depression and returns the accelerator pedal to its original position.
A case where an upshift jump speed such as the fourth speed is performed will be described.

First, while the vehicle is traveling at the second speed with the accelerator pedal depressed, the process goes from step S1 to step S2, where the pre-shift speed G0 is set to the second speed, and steps S3 to S5, S7, After S9 and S10, the provisional gear stage G2 is set to the second speed. Next, after steps S12 to S14, the re-shift prohibition flag F50 is set to 0, and then, through steps S15, S21, and S23, the provisional gear stage G3 is set to the second speed in step S24. In this case, the result of the determination in step S21 is NO because the flag F7
The precondition for setting the value of 0 to 1 is now 2-
This is because the state is such that a four-jump shift is performed, and the value of the flag F70 is set to 0 at the present time.

Then, through steps S25 to S26, and from steps S27 to S28, the post-shift gear stage G is set to the second speed, and as a result, step S2
In 9 and S30, the second speed, which is the current traveling gear, is maintained.

Next, when the driver suddenly stops depressing the accelerator pedal and returns to the original position, the operation proceeds from step S1 to step S1.
2, the pre-shift speed G0 is set to the second speed, and the temporary speed G2 is set to the fourth speed through steps S3 to S6. In this case, the 2-4 jump shift prohibition flag F
The value 24 is set to 0 because the determination condition of step S104 shown in FIG. 15 includes that the throttle opening θ is larger than the predetermined value TVO24. Therefore, YES is determined in step S5.

Then, after steps S12 to S14 are performed, the re-shift prohibition flag F50 is set to 0.
The process proceeds from step S15 to step S21. If the vehicle speed is higher than the predetermined value, the flag F70 is set to 1, and the process proceeds to step S22 to set the provisional gear stage G3 to the third speed. Then, via steps S25 to S26 and via steps S27 to S28, the post-shift gear stage G is set to the third speed, and finally, in step S29, 2-3 shift is determined, and step S30 is determined. At 2
-3 shift control is executed.

On the other hand, if the vehicle speed is not higher than the predetermined value at step S21, the flag F70 is set to 0, so that the routine proceeds to step S23, where the temporary gear G3 is set to the fourth speed. Then, via steps S25 to S26, and via steps S27 to S28, the post-shift gear stage G is set to the fourth speed, and eventually the step S
At 29, the 2-4 shift is determined, and the 2-4 shift control is executed at step S30.

As a result, when the vehicle speed is high, the jumping of the 2-4 upshift is prohibited, and
The shift is performed in the order of the third speed, the fourth speed, and the fourth speed.

That is, the factors that reduce the durability of the 3-4 clutch 53 that is released at the second speed and engaged at the third speed and the fourth speed are factors other than the change in the turbine speed before and after the shift and the magnitude of the torque. In addition, the deviation of the rotation speed before engagement between the input-side rotation element and the output-side rotation element that rotate integrally after the engagement, that is, the relative rotation speed between the two rotation elements before the shift is also a factor. . For example, even when the transmission ratio is the same at the same second speed, the relative rotation speed between the input-side rotary element and the output-side rotary element is higher at a high vehicle speed than at a low vehicle speed. In this way, a large load is applied by integrating these components to have the same rotational speed.
The clutch 53 is engaged, and this also affects the durability of the 3-4 clutch 53. Therefore, when the jumping of the 2-4 upshift is prohibited at the high vehicle speed, the problem of the decrease in the durability of the 3-4 clutch 53 is suppressed, and when the 2-4 jump shifting is permitted at the low vehicle speed. In this case, even if the accelerator pedal is depressed during the jumping operation and torque is generated as a result, the vehicle speed is low,
A very large load is not applied to the four clutch 53, and the problem of lowering the durability of the 3-4 clutch 53 is more effectively suppressed.

As described above, when the driver depresses the accelerator pedal but performs an operation to return the accelerator pedal to the original position in a short time, and as a result, once the shift in the downshift direction occurs, If it is determined that this 2-4 upshift jump shift is performed, the flag F6
Since the value of 0 is 1, even if the flag F
Even if the value of 70 is set to 1, the process proceeds from step S21 to S23 in order to prevent discomfort such as emblem or the like, and the jumping of the 2-4 upshift is permitted.

[0155]

As described above, according to the present invention, the value relating to the vehicle speed is detected by the vehicle speed detecting means. When the target shift speed of the higher gear is set this time by the target shift speed setting means, that is, when it is determined that the jump shift of the upshift should be performed, the target shift speed set previously is set to the currently set target shift speed. The direct shift to the target shift speed, that is, the above-mentioned upshift jump shift is prohibited by the jump shift prohibiting means.

That is, the factors that reduce the durability of the engagement-side friction element include the change amount of the turbine speed before and after the shift and the magnitude of the torque before and after the shift as described above. The deviation of the rotational speed of the rotary element between the rotary element on the output side and the rotary element on the output side before the engagement, that is, the relative rotational speed between the rotary elements before the speed change is also a factor. For example, even when the transmission ratio is the same at the same second speed, the relative rotation speed between the input-side rotary element and the output-side rotary element is higher at a high vehicle speed than at a low vehicle speed. As a result, a greater load will be applied to the fastening-side friction element in order to integrate them into the same rotational speed,
This also affects the durability of the friction element.

Therefore, the first invention is intended to suppress the problem of a decrease in the durability of the engagement-side friction element by prohibiting the jump shift at a high vehicle speed, and to permit the jump shift at a low vehicle speed. In this case, even if the accelerator is depressed during the jump shift operation and the torque is generated as a result, the vehicle is at a low vehicle speed, so that a large load is not applied to the engagement-side friction element. Even at vehicle speed, when the throttle opening is equal to or less than a predetermined value, it is possible to more effectively suppress the problem of deterioration in durability of the engagement side friction element as compared with the conventional technology that allows jump jumps uniformly. Become.

In this case, according to the second invention, in particular, when the value relating to the engine load is detected by the engine load detecting means and at least one of the detected value and the value relating to the vehicle speed is equal to or more than a predetermined value, When it is determined that the upshift jump speed should be performed, the upshift jump speed is prohibited by the jump speed shift inhibiting means.

Thus, when the throttle opening is equal to or more than a predetermined value and torque is generated, when the vehicle speed is a predetermined value and the relative rotational speed is large, when any of the relative speeds is equal to or more than a predetermined value, or when any one is equal to or more than a predetermined value In this case, jump shifting is prohibited, and together with these prohibition conditions, it is possible to more effectively suppress the problem of reduction in durability of the engagement-side friction element.

According to the third invention, in particular, it is determined whether or not the value related to the vehicle speed is equal to or more than a predetermined value from the detection result of the driving state detecting means for detecting the driving state for setting the target gear position. Therefore, it is not necessary to newly provide a means for detecting a value relating to the vehicle speed for determining whether to permit or prohibit the jump shift.

On the other hand, according to the fourth invention, particularly, for example,
A -4 upshift jump shift, a 2-5 upshift jump shift, and the like are prohibited at a high vehicle speed, thereby suppressing a problem of a decrease in durability of a friction element that is engaged only in a third or higher gear. Will be.

According to the fifth aspect of the present invention, in particular, when the jump shift of the upshift is the second shift in the multiplex shift generated during the first downshift, the upshift is exceptionally made. Shift jumping is permitted. Such multiple shifts occur, for example, when the driver once requests acceleration and depresses the accelerator pedal, but immediately stops and depresses the accelerator pedal. Accordingly, in such a case, if the first downshift is completed, the driver may reduce or cancel the depression of the accelerator pedal, and the emblem or the engine speed may increase, causing a sense of incongruity. Therefore, in such a case, the process immediately shifts to the second upshift jump shift even during the first downshift.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram showing a mechanical configuration of an automatic transmission according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a configuration of a transmission gear mechanism of the automatic transmission.

FIG. 3 is a circuit diagram of a hydraulic control circuit.

FIG. 4 is a sectional view showing a configuration of a hydraulic actuator of a 2-4 brake.

FIG. 5 is a control system diagram for each solenoid valve in the hydraulic control circuit.

6 is a main part enlarged circuit diagram showing a state of a first speed of the hydraulic control circuit of FIG. 3;

FIG. 7 is a main part enlarged circuit diagram showing a state of the second speed in the same manner.

FIG. 8 is an enlarged main part circuit diagram showing a state of the third speed in the same manner.

FIG. 9 is an enlarged circuit diagram of a main part showing a state of the fourth speed in the same manner.

FIG. 10 is a main part enlarged circuit diagram showing the state of the L range first speed.

FIG. 11 is an enlarged circuit diagram of a main part showing a state of a reverse speed in the same manner.

FIG. 12 is a flowchart illustrating a control program for automatic shifting.

FIG. 13 is a flowchart of the same.

FIG. 14 is a map diagram of a shift pattern.

FIG. 15 is a flowchart showing a program for setting a jump shift prohibition flag.

FIG. 16 is a time chart showing changes in data at the time of a 4-2-4 shift.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Automatic transmission 30, 40 Transmission gear mechanism 51-55 Friction element 100 Hydraulic control circuit 121-123 Duty solenoid valve 300 Control unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kenji Sawa 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd.

Claims (5)

[Claims] 1. A torque converter, a transmission gear mechanism,
Operating state detecting means for selectively detecting the operating state of the vehicle, comprising: a plurality of friction elements for realizing a plurality of shift speeds by switching a power transmission path of the gear mechanism; and Target speed setting means for setting the target speed based on the detection result; and control means for controlling the engagement state of the friction element so as to perform the shift to the target speed set by the setting means. A control device for an automatic transmission, comprising: a vehicle speed detecting means for detecting a value relating to a vehicle speed; When the target gear speed of the gear that is two or more steps larger than the gear speed of the target gear speed set this time is set this time, the direct shift from the previously set target gear speed to the currently set target gear speed is prohibited. Control apparatus for an automatic transmission, characterized in that is provided with the interlaced shift prohibiting means for. 2. A torque converter, a speed change gear mechanism,
Operating state detecting means for selectively detecting the operating state of the vehicle, comprising: a plurality of friction elements for realizing a plurality of shift speeds by switching a power transmission path of the gear mechanism; and Target speed setting means for setting the target speed based on the detection result; and control means for controlling the engagement state of the friction element so as to perform the shift to the target speed set by the setting means. A control device for an automatic transmission, comprising: a vehicle speed detecting means for detecting a value relating to a vehicle speed; an engine load detecting means for detecting a value relating to an engine load; and a value relating to a vehicle speed or an engine load detected by these detecting means. When at least one of the values is equal to or greater than a predetermined value, the target gear is two or more gears larger than the gear of the target gear previously set by the target gear setting means. An automatic shifting device comprising: an interlocking shift inhibiting means for inhibiting a direct shift from the previously set target gear to the currently set target gear when the gear is set this time. Machine control device. 3. A torque converter, a speed change gear mechanism,
A plurality of friction elements that are selectively engaged to switch a power transmission path of the gear mechanism to realize a plurality of shift speeds, and that includes at least a value related to a vehicle speed and a value related to an engine load; Gear position setting for setting a target gear position based on a shift characteristic preset according to a detection result of the detection device and at least a value relating to vehicle speed and a value relating to engine load. Control means for controlling an engagement state of the friction element so that a shift to the target gear set by the setting means is performed, wherein the operation state detection means When the value related to the vehicle speed detected in step (b) is equal to or greater than a predetermined value, the target gear position setting means sets the gear position of the target gear position that was previously set by two or more times. When the next target gear is set this time, an interlocking shift inhibiting means is provided that inhibits a direct shift from the previously set target gear to the currently set target gear. Control device for automatic transmission. 4. A torque converter, a speed change gear mechanism,
Operating state detecting means for selectively detecting the operating state of the vehicle, comprising: a plurality of friction elements for realizing a plurality of shift speeds by switching a power transmission path of the gear mechanism; and Target speed setting means for setting the target speed based on the detection result; and control means for controlling the engagement state of the friction element so as to perform the shift to the target speed set by the setting means. A control device for an automatic transmission, wherein the plurality of friction elements include a friction element that is engaged only at a third or higher gear, and a vehicle speed detection unit that detects a value related to a vehicle speed. The target gear position of the second or lower gear is set by the target gear setting means, and the target gear of the fourth gear or higher this time has a value related to the vehicle speed detected by the detecting means. When set at least values,
A control device for an automatic transmission, comprising: an intermittent shift prohibiting unit for prohibiting a direct shift from a previously set target gear to a currently set target gear. 5. A shift to a target shift speed set last time is as follows:
If the current target gear is set during a gear shift from a gear higher than the target gear and a gear shift to the previously set target gear is performed, the jump gear shift inhibiting means is set to the previous gear. The automatic transmission according to any one of claims 1 to 4, wherein a direct shift from the set target shift speed to the currently set target shift speed is permitted. Control device.