JPH07286662A - Speed change controller for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent dispersion of control by stopping or changing either of engine blow-up suppression control and tie-up suppression control when the blow-up and the tie-up of the engine are generated simultaneously or alternately in clutch-to-clutch speed change. CONSTITUTION:In speed change control of an automatic transmission 3, generating conditions of blow-up, in which the engine speed is increased, and a tie-up, in which the engine speed is reduced, are detected, when clutch-to-clutch speed change, in which the first frictional engaging device 1 is released while the second frictional engaging device 2 is engaged, is carried out. Then, engine output or engaging oil pressures of the frictional engaging devices 1, 2 are controlled for suppressing the blow-up and the tie-up of the engine. When a condition detecting means 4 detects that the blow-up and the tie-up are generated simultaneously or alternately, control is carried out for stopping or changing either the blow-up suppression control or the tie-up suppression control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for controlling engine upswing and tie-up during a shift by an automatic transmission, and more particularly to a friction engagement device such as two clutches and brakes. The present invention relates to a shift control device that performs control for suppressing blow-up and tie-up at the time of clutch-to-clutch shift performed by engaging / disengaging.

[0002]

2. Description of the Related Art To shift gears in an automatic transmission, a friction engagement device such as a clutch or a brake is switched between engaged and disengaged states.
It is well known that this is executed by changing the power transmission path. In the case of the speed change, the rotational speed of the rotating member including the engine changes, and it is necessary to absorb this to prevent the speed change shock. Therefore, the friction engagement device is transiently slid to reduce the energy accompanying the rotational fluctuation. Is controlled, or the switching of the engagement / release state of the friction engagement device is started in a state where the engine speed is sufficiently changed. For example, a clutch for switching between the engaged and disengaged states of two friction engagement devices at the same time
In the case of two-clutch shift, if it is an upshift, the transmission torque capacities of these friction engagement devices are maintained for a predetermined period until the engine speed drops to some extent, that is, the overlap period is set and the engine If it is a downshift, on the contrary, set those friction engagement devices to the released state until the engine speed rises to some extent, that is, set the underlap period to prevent tie-up. There is. Further, conventionally, when gear shifting is performed, gear shifting shock is reduced, load applied to the friction engagement device is reduced to prevent deterioration of durability thereof, and further, response delay of gear shifting control is prevented. The control for temporarily reducing the engine output is being performed.

By the way, engine blow-up is a temporary increase in the number of revolutions that occurs when the load on the engine is reduced because the torque capacities of the two friction engagement devices involved in gear shifting are relatively small. When the output is reduced, the load on the two friction engagement devices is reduced and the torque capacity thereof is relatively increased. Therefore, the torque reduction control of the engine advantageously acts to suppress the engine blow-up. . On the other hand, the tie-up is a reduction in the engine speed that occurs when the load on the engine is increased because the torque capacities of the two friction engagement devices involved in gear shifting are relatively large. When the load of the two friction engagement devices is made relatively small by performing the above, the torque capacity thereof is relatively increased and the tie-up state becomes more remarkable.

As described above, engine up and tie-up are opposite phenomena, and control for suppressing one becomes control for increasing the other. Therefore, for example, in the invention described in Japanese Patent Laid-Open No. 2-37128, the engine blow-up and pull-in (tie-up) at the time of shifting are detected, and when the blow-up occurs, the torque reduction amount of the engine is increased, On the contrary, when tie-up occurs, learning control is performed so as to reduce the torque reduction amount of the engine. Further, since the engine upstroke and tie-up are related to the torque capacity of the friction engagement device involved in gear shifting, the engagement hydraulic pressure of the friction engagement device is learned and controlled to suppress the upstroke and tie-up. Things have also been done conventionally.

[0005]

Since the torque capacity of the friction engagement device is determined by the friction coefficient of the friction material and the engagement oil pressure, the friction engagement device has a torque capacity for controlling upswing and tie-up of the engine. The engagement pressure is controlled directly or via an accumulator. Further, in order to correct the influence of the viscosity of oil (fluid) due to the oil temperature and the influence of the manufacturing error of the hydraulic control device and the friction engagement device, the control value is learned and corrected at each shift. However, for example, when the friction coefficient changes significantly due to deterioration with time of the friction material, the torque reduction amount at the time of gear shift and the control amount of the engaging hydraulic pressure obtained by the learning control become larger than in the normal state. However, the control amount of the torque reduction control or the hydraulic pressure control for preventing the engine from rising up becomes unsuitable as the control amount for suppressing the tie-up. The correction amount obtained by learning control in such a case is appropriate for either the purpose of preventing engine blow-up or tie-up, but becomes an inappropriate value for the other control. Therefore, in the end, there is a possibility that the correction amount will not converge to a constant value and the control will diverge.

Further, even if there is an abnormality in the detection of engine blow-up, the detection of tie-up, or the learning control method, there is a possibility that the learning control itself is not normally executed and erroneous learning is performed.

The present invention has been made in view of the above circumstances, and an object thereof is to prevent divergence of control or erroneous learning when performing learning control for suppressing engine blow-up or tie-up. .

[0008]

In order to achieve the above-mentioned object, the present invention is characterized by having the structure shown in FIG. That is, the shift control device of the present invention is
When performing clutch-to-clutch shifting in which the first frictional engagement device 1 is released and the second frictional engagement device 2 is engaged, the engine speed increases and the engine speed decreases. Automatic transmission 3 for detecting at least one of the engine output and the engagement hydraulic pressure of the friction engagement devices 1 and 2 so as to detect the occurrence state of tie-up and the engine up and tie-up. And a state detecting means 4 for detecting that the upstroke and the tie-up occur simultaneously or alternately, and the up-shift suppression when the upstroke and the tie-up occur simultaneously or alternately. It is characterized in that it is provided with a means 5 for stopping or changing either one of the control and the tie-up suppression control.

[0009]

In the speed change control device of the present invention, engine upswing and tie-up are detected during clutch-to-clutch shifting, and the engine output or the friction engagement devices 1 and 2 are controlled so as to suppress them. The combined pressure is controlled. When the engine blow-up and tie-up occur simultaneously or alternately, the state detecting means 4 detects this. When the engine rotation state detecting means 4 outputs the detection signal, the means 5 suspends or changes the control for suppressing the engine blow-up or the control for suppressing the tie-up. Therefore, the engine output or the engagement pressure of the friction engagement device is controlled so as to suppress only the engine blow-up or tie-up.
It is possible to prevent divergence of control due to so-called interference between the engine uphill suppression control and the tie-up suppression control.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 2 is a block diagram showing the basic configuration of an embodiment of the present invention, and the example shown here is for an automatic transmission A capable of setting 5 forward gears and 1 reverse gear. Is. Therefore, first, the structure of the gear train of the automatic transmission A will be described. In the automatic transmission A, a torque converter 11 having a lockup clutch 10 as a speed change mechanism, and a sub-transmission unit 12 having a set of planetary gear mechanisms. And a main transmission unit 13 that sets a plurality of forward gears and reverse gears by two sets of planetary gear mechanisms. The sub-transmission unit 12 performs high-low two-stage switching, the carrier 14 of the planetary gear mechanism is connected to the turbine runner 15 of the torque converter 11, and the carrier 14 and the sun gear 16 are connected to each other. Between clutch C0
And a one-way clutch F0 are provided in parallel relationship with each other, and a brake B0 is provided between the sun gear 16 and the housing Hu.

On the other hand, the sun gears 17 and 18 in each planetary gear mechanism of the main transmission portion 13 are provided on a common sun gear shaft 19, and the ring gear 20 in the left (front side) planetary gear mechanism of the main transmission portion 13 is provided. A first clutch C1 is provided between the sun gear shaft 19 and the ring gear 21 of the sub transmission unit 12, and a second clutch C2 is provided between the sun gear shaft 19 and the ring gear 21 of the sub transmission unit 12. The carrier 22 of the planetary gear mechanism on the left side of the figure and the ring gear 23 of the planetary gear mechanism on the right side (rear side) of the main transmission unit 13 are integrally coupled, and the output shaft 24 is connected to these carrier 22 and ring gear 23. Are connected.

A first brake B1 which is a band brake is provided to stop the rotation of the sun gear shaft 19,
More specifically, the first one-way clutch F1 and the third brake B3 are provided on the outer peripheral side of the clutch drum of the second clutch C2, and between the carrier 25 and the housing Hu in the planetary gear mechanism on the rear side. Are arranged in parallel.

In the automatic transmission A having the above structure,
By engaging / disengaging each frictional engagement device as shown in FIG. 3, five forward gears and one reverse gear are set. Note that, in FIG. 3, the mark ◯ indicates engagement and the mark x indicates release.

Each clutch C in the above automatic transmission A
The hydraulic control device 30 for supplying / discharging the hydraulic pressure to / from 0, C1, C2 and the brakes B0, B1, B3 includes first to third solenoid valves for mainly setting the first speed to the fifth speed and the reverse gear. S1, S2, S3, a linear solenoid valve SLU for controlling the lockup clutch 10 and adjusting the supply pressure of the brake B0, a linear solenoid valve SLT for controlling the line hydraulic pressure PL according to the throttle opening, A linear solenoid valve SLN for controlling the back pressure of the accumulator is provided. An electronic control unit (T- for controlling these solenoid valves
ECU) 31 is provided, which mainly includes a central processing unit (CPU), storage elements (ROM, RAM), and an input / output interface.
Signal from input speed sensor to automatic transmission A, first
Signal from rotation speed sensor of clutch C1, vehicle speed signal, signal from neutral start switch, signal from oil temperature sensor, signal from pattern select switch, signal from transmission control switch, signal from stop lamp switch, etc. Has been entered. An electronic control unit (E-ECU) 32 for an engine is connected to the electronic control unit 31 so as to be able to perform data communication with each other. A signal from the throttle position sensor, a signal from the water temperature sensor, etc. are input to the electronic control unit 32 for the engine.

Electronic control unit 31 for the above automatic transmission
Controls the gears to be set and engagement / disengagement of the lockup clutch 10 on the basis of each input signal and a map stored in advance, and controls the engine electronic control unit 32 at the time of gear shifting. A signal is output so as to execute the torque down control.

The engine to which the automatic transmission A is connected is an engine configured to perform combustion pause control or control of the combustion state based on the ignition timing and the fuel injection amount with a predetermined number of cylinders as a group. One example is a V-type engine that performs the above control for each cylinder of the left and right banks. FIG. 4 is a diagram schematically showing this engine. Intake pipes 42 and 43 are provided as a group of cylinders (not shown) of the left bank 40 and the right bank 41, respectively. 42 and 43 are provided with electronic throttle valves 44 and 45 whose opening is electrically controlled.
The exhaust ports (not shown) of the cylinders of the left and right banks 40 and 41 are connected to the exhaust manifolds 46 and 47.
The exhaust pipes 48, 49 are connected via the. Exhaust gas purification catalysts 50 and 51 are provided in these exhaust pipes 48 and 49, respectively.

Further, the ignition timing, the fuel injection amount, and the throttle opening in the cylinders of the left and right banks 40 and 41 are constructed so as to be controlled independently of each other. ,
A left bank control engine computer 52 and a right bank control engine computer 53 are provided. Each of these engine computers 52, 53
While being connected to the automatic transmission electronic control unit 31 so as to be able to perform data communication, the corresponding left and right exhaust purification catalysts 50,
The temperature of 51 is input as data.

Further, these engine computers 52,
53 is the corresponding left and right electronic throttle valves 44,
The ignition timing or the fuel injection amount in the cylinders of the bank 45 and the corresponding left and right banks 40 and 41 is controlled. Specifically, the opening degree of the electronic throttle valves 44, 45 is controlled according to the accelerator operation amount, and the control amount (throttle opening degree), control timing, etc. are set in the automatic transmission A. It is designed to be changed according to the timing of gear shifting and the like. Further, in order to reduce the torque during the gear shift in the automatic transmission A, the torque during the stall, or the torque during the sudden engagement, the ignition timing, the fuel injection amount, and the sub throttle valve, if any, are provided. The opening is controlled.

By the way, as is known from the engagement operation table shown in FIG. 3, in the automatic transmission A described above, when shifting between the third speed and the fourth speed, the second clutch C2 and the first brake are used. It is necessary to change the engagement / disengagement state with B1 at the same time, so that the shift between these shift speeds is a so-called clutch-to-clutch shift. When performing this shift, these two friction engagement devices are operated for a predetermined period of time in order to prevent the engine from being blown up in the case of an upshift and to prevent a shift shock in the case of a downshift.
It is necessary to maintain the overlap state or the underlap state. In order to perform such control, the automatic transmission A is provided with the hydraulic circuit shown in FIG.

In FIG. 5, reference numeral 70 denotes a 3-4 timing valve, and the 3-4 timing valve 70 has a 3-4 timing valve.
The import 73 communicating with the drain oil passage 72 of the shift valve 71, the drain pressure input port 75 communicating with the drain oil passage 72 via the orifice 74, and the oil supplied from the 3-4 shift valve 71 to the second clutch C2 Road 76
An input port 78 communicating with the
Linear solenoid valve SLU for lockup clutch
A signal port 79 to which the signal pressure from is input and a drain port 80 are provided. Further, the spool 81 of this 3-4 timing valve 70 has a land 82 located at one end thereof for opening and closing the drain port 80 and a drain 82 located in the middle and for partitioning between the drain pressure input port 75 and the import 73. A land 83 forming a drain pressure receiving surface on the side of the pressure input port 75 and a small diameter land located at the other end and forming a supply pressure receiving surface and partitioning the input port 78 and the drain pressure input port 75. And 84. The land 82 on one end side thereof contacts the pressure receiving piston 86 via the spring 85, and the pressure receiving piston 86 forms a pressure receiving surface for the signal pressure from the signal port 79.

Accumulator 8 for the first brake B1
7 is connected to an oil passage 88 leading to the first brake B1 via an orifice 89, and this accumulator 8
Reference numeral 7 controls the engagement pressure of the first brake B1 by changing the back pressure by the hydraulic pressure from the accumulator control valve controlled by the linear solenoid valve SLN. The accumulator 9 for the second clutch C2
Similarly, for 0, the back pressure is changed by the hydraulic pressure from the accumulator control valve controlled by the linear solenoid valve SLN to control the engagement pressure of the second clutch C2.

Further, in FIG. 5, reference numeral 91 is a C-2 orifice control valve which constitutes a first fill means for the second clutch C2, and is an end portion provided with a spring 93 for pressing the spool 92 in its axial direction. A control port 94 is formed at the opposite end, and the control port 94 is provided with the second clutch C via the orifice 95.
It is connected to 2. In the middle part, the supply oil passage 7
An input port 96 to which 6 is connected, and a second clutch port 97, which is connected to and disconnected from the input port 96 by a spool 92 and to which a second clutch C2 is connected, are formed. B-1 control valve 9 described later
A first brake port 99 connected to the first brake B1 via a drain port 10 connected to and disconnected from the first brake port 99 by a spool 92.
0 and 0 are formed. A signal port 101 for inputting the signal pressure from the third solenoid valve S3 is formed at the end where the spring 93 is arranged.

Explaining the B-1 control valve 98, this is a valve for controlling the supply / discharge speed of the hydraulic pressure of the first brake B1, and is an oil valve for causing the hydraulic pressure of the first brake B1 to act as a signal pressure. The signal port 102 connected to the passage 88, the D port 104 connected to the 3-4 shift valve 71 via the orifice 103, and the brake port connected / disconnected to the D port 104 and connected to the oil passage 88 105 and this brake port 10
The first brake port 99 of the C-2 orifice control valve 91, which is connected to and disconnected from the No.
And a brake port 106 connected to. One end of the spool 107 that opens and closes these ports is brought into contact with the piston 109 via a spring 108. A control port 11 that opens between the spool 107 and the piston 109 and is supplied with the fourth speed pressure.
0 and a signal pressure port 111 to which the signal pressure of the lock-up clutch linear solenoid valve SLU is applied to the piston 109. In FIG. 5, reference numeral 112 is a 2-3 shift valve, and reference numeral 11
Reference numeral 3 is an orifice provided in the drain oil passage 74.

That is, the 3-4 timing valve 70 is shown in FIG.
By switching from the position shown in the upper half to the position shown in the lower half, the import 73 communicates with the drain port 80 and increases the exhaust pressure speed from the first brake B1, so that the speed from the third speed to the fourth speed is increased. By controlling the hydraulic pressure supplied to the control port 79 by the linear solenoid valve SLU during the upshift, the second clutch C2 and the first clutch C2
The overlap period with the brake B1 is controlled appropriately. When downshifting from the 4th speed to the 3rd speed, the hydraulic pressure supplied to the control port 111 of the B-1 control valve 98 is supplied to the linear solenoid valve SLU.
5 to control the timing at which the B-1 control valve 98 switches to the position shown in the upper half of FIG. 5, thereby controlling the hydraulic pressure supply timing for the first brake B1 to control the second clutch C2 and the first brake. B
The underlap period of 1 is controlled appropriately.

The control of the overlap period and the underlap period by the above-mentioned linear solenoid valve SLU is controlled so as to prevent the engine from blowing up or tie-up during clutch-to-clutch shifting. The control value (for example, duty ratio) of the valve SLU is corrected based on the engine blow-up or tie-up state at the time of the shift, and the next clutch toe
Used to control clutch shifting. That is, learning control is performed. However, depending on, for example, the progress of deterioration of the friction material of the friction engagement device, it may not be possible to prevent the engine from being blown up or tied up even by the learning control. The above-described control device according to the present invention performs control for preventing the engine from blowing up or tie-up during clutch-to-clutch gear shifting as follows.

In FIG. 6, it is judged whether or not there is a state in which clutch-to-clutch shifting (for example, upshifting from the third speed to the fourth speed) should be performed based on the signal indicating the running state (step 1). If it is established, the shift output is performed (step 2). Specifically, the solenoid valve for shifting is switched. Next, it is determined whether the engine is going up (step 3). This is a known determination method, for example, by detecting a decrease state of the input rotation speed (engine rotation speed) during gear shifting and determining that the engine has blown up if the rotation speed is higher than a target rotation speed to some extent or more. Can be adopted. When the engine is blown up, the engine blowup state such as the rotation speed and duration is detected (step 4).

Further, it is determined whether or not the control for reducing the output torque of the engine (torque down) in order to prevent the engine from rising is permitted (step 5). The non-permission condition is, for example, the temperature of the exhaust purification catalyst, and if the temperature is equal to or lower than a predetermined temperature, the exhaust may deteriorate due to the ignition retard control, so the torque down control is not permitted. Become. If the result of the determination in step 5 is "yes", that is, if the real-time torque down control is permitted, this is executed (step 6) to suppress engine upswing. FIG. 7 is a control map of the torque reduction, in which the amount of torque reduction is determined according to the amount of engine blow-up (rotational speed) and the duration thereof. For achieving this, for example, ignition timing retard control I do.

Then, it is judged whether or not tie-up has occurred (step 7). Various conventionally known methods can be adopted as the determination method. For example, the tie-up can be determined when the input rotation speed (engine rotation speed) is lower than the target rotation speed by a predetermined amount or more. .
When the tie-up is detected, the control value (duty ratio) Dslu of the linear solenoid valve SLU is left unchanged (step 8). That is, clutch, toe,
If the engine is blown up during the upshift of the clutch shift, it is usual to increase the duty ratio Dslu of the linear solenoid valve SLU in order to suppress it, but tie-up is also occurring at the same time. In this case, the engine speed up control is controlled by torque reduction without changing the duty ratio Dslu. That is, the learning control of the duty ratio Dslu is not performed here. Instead of this, the control gain K2 described later may be changed. Therefore, the tie-up becomes more conspicuous due to the engine up-rising suppression control, and the control does not diverge such as the engine up-rising increases by controlling the tie-up to be suppressed. Absent.

Then, the learning control of the torque reduction amount (step 9) is performed and the process returns. In that case, the torque reduction amount at the time of the next clutch-to-clutch shift or the shift immediately after this may become inappropriate. Therefore, for example, a value obtained by reducing the torque reduction amount in the map shown in FIG. 7 by 1% is used. Used as the next control value (learning value).

On the other hand, when the result of the determination in step 7 is "no", that is, when tie-up has not occurred, the duty ratio Dslu is controlled so as to suppress the engine from rising.
Is increased and corrected (step 10). Specifically, the duty ratio Dslu is increased by a value obtained by multiplying the correction amount ΔDslu by the control gain k2 (Dslu = Dslu + k2 ×).
ΔDslu). Therefore, in this case, engine upswing can be suppressed or prevented without deteriorating the shift shock caused by tie-up.

Further, when the result of the determination in step 5 is "NO", that is, when the torque down control in real time is not permitted, the electronic throttle valve 4 is used.
The torque is reduced by decreasing the openings of 4, 45 (step 11). Then, it is judged whether or not tie-up has occurred (step 12). If tie-up has occurred, the duty ratio Dsl of the linear solenoid valve SLU is determined.
u is maintained at the previous value (step 13), and the process returns. On the other hand, if there is no tie-up,
The duty ratio Dslu is increased and corrected (step 14).
That is, a value obtained by multiplying the correction amount ΔDslu by the control gain k3 is added (Dslu = Dslu + k3 × ΔDslu). The control gain k for correcting the duty ratio Dslu
2, k3 can be stored as a map, and an appropriate control gain can be used according to the engine blow-up state (blow-up amount and duration). An example of the map is shown in FIG.

If no engine uprising is detected during the upshift from the third speed to the fourth speed, that is, if the result of the determination in step 3 is "no", it is determined whether tie-up has occurred. Judgment (step 15), and if tie-up has occurred, it is judged whether or not the engine has blown up during the previous shift (step 1).
6). If the engine was blown up during the previous shift, one of the engine blowup detection methods, tie-up detection methods, or learning control methods is in an inappropriate state. In order to prevent learning, in this case, the process returns without any particular control. On the contrary, when the engine is not blown up at the previous shift, the duty ratio Dslu of the linear solenoid valve SLU is reduced and corrected in order to suppress or prevent the tie-up (step 17). Specifically, the correction value Δ
The duty ratio (Dslu = Dslu−k1 × ΔDslu) is obtained by subtracting the value obtained by multiplying Dslu by the control gain k1.
Further, in order to reduce the tie-up as much as possible, for example, the drain hydraulic pressure of the first brake B1 is set to be low at the time of the next gear shift at substantially the same throttle opening, or instead of this, or in addition to this. The control for sending the rising of the hydraulic pressure of the second clutch C2 is performed. The learning control in the present invention also includes learning of the hydraulic pressure control of the first brake B1 and the second clutch C2 of this kind.

In the above-described embodiment, only the case of upshifting from the third speed to the fourth speed has been described as an example. However, the present invention is not limited to the above-mentioned embodiment, so that other shifts can be performed. It can be applied to the case control. Further, it goes without saying that the present invention can be applied to a shift control device for an automatic transmission equipped with a gear train other than the gear train shown in the drawing. Further, in the above-described embodiment, when both engine up and tie-up occur, engine output torque reduction control is performed in order to suppress or prevent engine up-rising. Alternatively, the hydraulic pressure may be controlled so as to suppress or reduce the tie-up.

[0034]

As described above, according to the shift control device of the present invention, learning control for suppressing or preventing the engine blow-up and tie-up during clutch-to-clutch shift is performed. Despite this, if engine up and tie-up occur simultaneously or alternately, at least one of the engine up-control and the tie-up control may be stopped or changed. Therefore, it is possible to prevent divergence of the control, and it is possible to prevent a situation in which engine upswing and gear shift shock due to tie-up are worsened.

[Brief description of drawings]

FIG. 1 is a schematic block diagram showing the present invention by functional means.

FIG. 2 is a schematic diagram mainly showing a gear train in one embodiment of the present invention.

FIG. 3 is a diagram showing an engagement operation table of a friction engagement device for setting each shift speed.

FIG. 4 is a block diagram schematically showing a supply / exhaust system and a control system of a V-type engine capable of bank switching.

FIG. 5 is a diagram showing an example of a hydraulic circuit for controlling the timing of engagement / disengagement of a second clutch and a first brake.

FIG. 6 is a flowchart showing an example of a learning control routine for suppressing engine upswing and tie-up suppression.

FIG. 7 is a map showing an example of a torque reduction amount in real time.

FIG. 8 is a map showing an example of a control gain for addition correction of a duty ratio.

[Explanation of symbols]

 1, 2 Friction engagement device 3 Automatic transmission 4 State detection means 5 Means

Claims (1)

[Claims] 1. A blow-up and an engine rotation in which an engine speed increases when a clutch-to-clutch shift is performed in which a first friction engagement device is released and a second friction engagement device is engaged. Of the automatic transmission that controls the engine output and at least one of the engagement hydraulic pressure of the friction engagement device so as to prevent the engine from rising and tie-up while detecting the occurrence state of tie-up in which the number decreases. In the shift control device, a state detection unit that detects whether the upstroke and the tie-up occur simultaneously or alternately, and the up-shift suppression control and the tie-up when the up-stroke and the tie-up occur simultaneously or alternately. A shift control device for an automatic transmission, comprising means for stopping or changing one of the suppression control.