JPH08303574A - Control device for automatic transmission - Google Patents

Abstract

PURPOSE: To jumpingly shift without generating shift shock or shift delay by estimating a synchronous time with a shift step after shifting in the case of jump shift after the rotating speed of a rotary element exceeds the synchronous rotating speed of a first shift step adjacent to a second shift step to the second shift step side. CONSTITUTION: When judgement of down shift from a fifth speed and the like to a second speed is judged to be materialized, a 2-3 shift valve 71 and a 3-4 shift valve 72 are changed into a second shift condition, and the engaging pressure of a third brake B3 is modulated into low pressure to a certain extent putting close a back clearance by a B-3 control valve 78 and maintained. It is judged whether input rotating speed is over the synchronous rotating speed of a third speed or not, and in the case of being judged to be yes, the synchronous time of the input rotating speed with a second speed is estimated. The shifting condition from the third speed to the second speed is attained, and when the synchronous time for the second speed becomes the estimated condition, sweep-up control increasing in order the engaging pressure of the third brake B3 is begun.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a shift of an automatic transmission for a vehicle, and more particularly to a device for controlling a jump shift including a clutch-to-clutch shift.

[0002]

2. Description of the Related Art A so-called clutch-to-clutch shift is a shift executed by releasing a predetermined friction engagement device and engaging another friction engagement device different from the predetermined friction engagement device. If such a shift is performed, any of these shift stages can be set without using a one-way clutch, so that the automatic transmission can be made smaller and lighter. One example is JP-A-5-157167.
No., published in Japanese Unexamined Patent Publication No.

The automatic transmission described in this publication has a second
The shift between the third speed and the third speed is configured to be a clutch-to-clutch shift, and when the downshift from the third speed to the second speed is performed, the friction engagement device is engaged. The pressure is controlled as follows.

During downshifting, it is necessary to quickly and smoothly increase the input rotational speed to the synchronous rotational speed of the gear after shifting, so that the engaging pressure of the frictional engagement device on the releasing side is gradually increased after the output of the shift. The input rotational speed is decreased to increase the input rotational speed, and the engagement pressure of the frictional engagement device is kept low at the release side. In this way, the input rotation speed is changed, the synchronization timing to the second speed is predicted from the change rate of the input rotation speed during that time, and the engagement pressure of the engagement side frictional engagement device is gradually increased based on the prediction result. are doing. According to such control, it is possible to accurately detect the progress state of the shift, so that it is possible to control the engagement pressure of the friction engagement device according to it, and it is possible to effectively prevent the shift delay and shock. .

[0005]

In the above-described automatic transmission, the gear shift to the second speed is not limited to the gear shift from the adjacent gear, and for example, the higher speed side such as the fourth speed or the fifth speed is used. There is also a case of shifting from the shift stage. Even in the case of such a so-called jump shift, finally, the shift pressure is controlled by controlling the engagement pressure of the friction engagement device that is engaged at the second speed. In that case, the variation range of the input rotation speed is the third
Although it is longer than a shift from high speed, the time allowed for achieving a shift is limited to the same extent as in the case of shifting from an adjacent gear, so the specified rotation speed such as The method of changing the rotational speed of the element is different from that in the case of shifting from the adjacent gear.

Further, the torque capacity and drag torque characteristic of the friction engagement device which sets the fourth speed and the fifth speed are different from those of the friction engagement device which sets the adjacent gear such as the third speed. ing. Therefore, the state of change in rotation such as the input rotation speed in the case of a shift from a shift stage that is a so-called interlaced shift is different from that in a normal shift from an adjacent shift stage.

In this way, in the case of the interlaced shift including the clutch-to-clutch shift, the engagement pressure of the frictional engagement device on the engaging side is simply changed as in the control by the above-mentioned conventional device. If the control is performed by predicting the synchronization timing from the above, there is an inconvenience that the shift shock becomes large due to the inaccurate prediction of the synchronization timing, which is the premise thereof.

The present invention has been made in view of the above circumstances, and a control device capable of executing an interlaced shift including clutch-to-clutch shift without causing inconveniences such as shift shock and shift delay. It is intended to provide.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a clutch-to-clutch shift in which gear shifts from adjacent gears exceed the adjacent gears. When an interlaced shift is performed from a shift stage, the speed change rate of a predetermined rotary element for determining the shift state and the prediction of the synchronization timing based on the change rate are predicted to the shift stage adjacent to the shift stage after the shift. Is held until the synchronization is detected, and then the synchronization to the gear after the shift is predicted.

More specifically, according to the present invention, as shown in FIG. 1, by releasing the first frictional engagement device 1 and engaging the second frictional engagement device 2, the first gear shift is performed. When shifting from the first gear to the second gear, the second frictional engagement device 2 is increased in pressure from the low pressure standby state by synchronous rotation from the predetermined rotational speed change rate of the rotary element 3 to the second gear. In a control device for an automatic transmission 4 that predicts and executes a timing, an interlaced shift judging means 5 for deciding a gear shift to a second gear stage that has skipped the first gear stage, and the above-mentioned interlaced gear shift determination means for performing the interlaced gear shift. An intermediate synchronization determination means 6 for determining that the rotational speed of the rotating element 3 has exceeded the synchronous rotational speed of the first gear shift to the synchronous rotational speed side of the second gear, and the rotational speed of the rotary element 3 is It was determined that the synchronous speed of the first gear was exceeded to the synchronous speed of the second gear. And it is characterized in that it comprises a synchronization prediction unit 7 that predicts the synchronization timing of the rotational speed of the rate of change of the rotating element 3 to the case to the second speed stage.

[0011]

In the automatic transmission to which the present invention is applied, the gear shift from the first gear stage to the second gear stage changes the engaged / released state of the first and second friction engagement devices 1 and 2. It is configured so that clutch-to-clutch shifting can be changed. When executing this gear shift, the second frictional engagement device 2 on the engagement side is maintained at a low engagement pressure, and thereafter, according to the prediction result of the synchronization timing based on the rotational speed change rate of the rotary element 3. The engagement pressure of the second friction engagement device 2 is increased.

If the shift to the second shift stage is a jump shift from another shift stage that exceeds the first shift stage, the jump shift determining means 5 determines this. In the case of this interlaced shift, the prediction of synchronization for performing the boosting control of the second frictional engagement device 2 that is the engagement side frictional engagement device is not performed immediately after the gearshift output, but first, the predetermined rotation element is used. The intermediate synchronization determination means 6 determines whether or not the rotational speed of 3 exceeds the synchronous rotational speed at the first shift stage. After the determination is made, that is, when the synchronous rotation speed in the first shift speed is exceeded, the synchronization timing to the second shift speed based on the change rate of the rotation speed of 3 of the rotary element by the synchronization predicting means 7 is reached. is expected.

Therefore, during the shift from the first shift stage to the second shift stage, the boost control after the low pressure standby of the second friction engagement device 2 is always performed from the first shift stage to the second shift stage. It is performed according to the prediction of the synchronization timing based on the rotation speed change rate during the shift to the shift stage, and as a result, the prediction of the synchronization timing to the second shift stage is accurate even in the interlaced shift, Accordingly, the pressure increase control of the second friction engagement device, which is the engagement side friction engagement device, is accurately performed, and the deterioration of the shock is prevented.

[0014]

The present invention will be described below with reference to the embodiments shown in the drawings. FIG. 2 is an overall control system diagram showing an embodiment of the present invention. An engine E to which an automatic transmission A is connected has an intake pipe 12 in which a main throttle valve 1 is provided.
3 and a sub-throttle valve 14 located upstream thereof. The main throttle valve 13 is connected to an accelerator pedal 15, and the accelerator pedal 15
It opens and closes according to the amount of depression. The sub-throttle valve 14 is opened and closed by a motor 16. An engine electronic control unit (E-ECU) 17 for controlling the motor 16 for adjusting the opening of the sub-throttle valve 14 and for controlling the fuel injection amount and ignition timing of the engine E is provided. There is. The electronic control unit 17 is mainly composed of a central processing unit (CPU), a storage unit (RAM, ROM), and an input / output interface. The electronic control unit 17 stores data for control as Engine (E
/ G) Various signals such as rotation speed N, intake air amount Q, intake air temperature, throttle opening, vehicle speed, engine water temperature, and signals from brake switches are input.

In the automatic transmission A, the hydraulic control device 18 controls gear shifting and lockup clutch, line pressure, or engagement pressure of a predetermined friction engagement device. The hydraulic control device 18 is configured to be electrically controlled, and also has first to third shift solenoid valves S1 to S3 for executing a shift and a first to third engine for controlling an engine braking state. 4 solenoid valve S4, linear solenoid valve SLT for controlling the line pressure, linear solenoid valve SLN for controlling the back pressure of the accumulator, linear for controlling the engagement pressure of a lock-up clutch or a predetermined friction engagement device A solenoid valve SLU is provided.

An electronic control unit (T-ECU) 19 for an automatic transmission that outputs a signal to these solenoid valves to control gear shift, line pressure, accumulator back pressure, etc.
Is provided. This automatic transmission electronic control unit 19
Is a central processing unit (CPU) and a storage device (RA
M, ROM) and an input / output interface, and this electronic control unit 19 indicates throttle opening, vehicle speed, engine water temperature, signals from brake switch, and shift position as data for control. Signal, signal from pattern select switch, signal from overdrive switch, clutch C described later
A signal from a C0 sensor that detects the rotational speed of 0, an oil temperature of the automatic transmission, a signal from a manual shift switch, and the like are input.

The electronic control unit 19 for the automatic transmission and the electronic control unit 17 for the engine are connected to each other so that they can communicate data with each other, and the electronic control unit 17 for the engine transfers to the electronic control unit 19 for the automatic transmission. On the other hand, a signal such as the intake air amount per rotation (Q / N) is transmitted, and an instruction signal for each solenoid valve is sent from the automatic transmission electronic control unit 19 to the engine electronic control unit 17. A signal equivalent to, a signal instructing a shift speed, and the like are transmitted.

That is, the electronic control unit 19 for the automatic transmission
Is based on the input data and the map stored in advance, and the ON / OFF of the gear position and the lockup clutch is performed.
F, or the line pressure or the adjustment level of the engagement pressure is judged, and based on the judgment result, an instruction signal is output to a predetermined solenoid valve, and further judgment of fail or control based on it is performed. . In addition to controlling the fuel injection amount, the ignition timing, the opening degree of the sub-throttle valve 14, etc. based on the input data, the electronic control unit 17 for the engine also sets the fuel injection amount during the shift in the automatic transmission A. The output torque is temporarily reduced by reducing the amount, changing the ignition timing, or narrowing the opening of the sub-throttle valve 14.

FIG. 3 is a diagram showing an example of a gear train of the above-described automatic transmission A, and in the configuration shown here, it is configured to set five forward gears and one reverse gear. That is, the automatic transmission A shown here is used in the torque converter 20.
And a sub-transmission unit 21 and a main transmission unit 22. The torque converter 20 includes a lockup clutch 23.
The lock-up clutch 23 has a front cover 25 that is integrated with the pump impeller 24.
A member (hub) in which the turbine runner 26 and the turbine runner 26 are integrally attached
It is provided between 7 and. An engine crankshaft (not shown) is connected to a front cover 25, and a turbine runner 26 is connected to an input shaft 28.
Is connected to a carrier 30 of an overdrive planetary gear mechanism 29 that constitutes the subtransmission unit 21.

The carrier 3 in this planetary gear mechanism 29
A multi-plate clutch C0 and a one-way clutch F0 are provided between 0 and the sun gear 31. The one-way clutch F0 is engaged when the sun gear 31 rotates forward relative to the carrier 30 (rotates in the rotation direction of the input shaft 28). Further, a multi-plate brake B0 for selectively stopping the rotation of the sun gear 31 is provided.
The ring gear 3 which is an output element of the subtransmission unit 21
2 is connected to an intermediate shaft 33 which is an input element of the main transmission unit 22.

Therefore, in the sub-transmission unit 21, the whole planetary gear mechanism 29 rotates integrally when the multi-plate clutch C0 or the one-way clutch F0 is engaged, so that the intermediate shaft 33 has the same speed as the input shaft 28. It will rotate at low speed. Further, in the state where the brake B0 is engaged and the rotation of the sun gear 31 is stopped, the ring gear 32 is accelerated with respect to the input shaft 28 to rotate in the normal direction, and the high speed stage is established.

On the other hand, the main transmission unit 22 is provided with three sets of planetary gear mechanisms 40, 50, 60, and their rotating elements are connected as follows. That is, the sun gear 41 of the first planetary gear mechanism 40 and the sun gear 51 of the second planetary gear mechanism 50 are integrally connected to each other, and the ring gear 43 of the first planetary gear mechanism 40 and the carrier 52 of the second planetary gear mechanism 50 are connected. The third planetary gear mechanism 60 and a carrier 62 are coupled to each other, and the carrier 62 is coupled to an output shaft 65. Further, the ring gear 53 of the second planetary gear mechanism 50 is connected to the sun gear 61 of the third planetary gear mechanism 60.

In the gear train of the main transmission unit 22, it is possible to set a reverse gear and four gears on the forward side, and a clutch and a brake for that purpose are provided as follows. First, the clutch will be described. The ring gear 53 and the third gear of the second planetary gear mechanism 50 which are connected to each other.
A first clutch C1 is provided between the sun gear 61 of the planetary gear mechanism 60 and the intermediate shaft 33, and the sun gear 41 of the first planetary gear mechanism 40 and the sun gear 51 and the intermediate shaft of the second planetary gear mechanism 50 are connected to each other. A second clutch C2 is provided between the first clutch 33 and the second clutch C3.

Next, the brake will be described. The first brake B1 is a band brake, and the sun gears 41 and 5 of the first planetary gear mechanism 40 and the second planetary gear mechanism 50 are the band brakes.
It is arranged to stop the rotation of 1. A first one-way clutch F1 and a second brake B2, which is a multi-disc brake, are arranged in series between the sun gears 41 and 51 (that is, the common sun gear shaft) and the casing 66. One way clutch F1 is sun gear 41,5
1 engages when trying to rotate in the reverse direction (rotation in the direction opposite to the rotation direction of the input shaft 28).

The third brake B3, which is a multi-disc brake, is provided between the carrier 42 of the first planetary gear mechanism 40 and the casing 66. Then, as a brake for stopping the rotation of the ring gear 63 of the third planetary gear mechanism 60, a fourth brake B4, which is a multi-disc brake, and a second one-way clutch F2.
And are arranged in parallel with the casing 66. The second one-way clutch F2 is adapted to be engaged when the ring gear 63 tries to rotate in the reverse direction.

In the above-described automatic transmission A, it is possible to set five forward speeds and one reverse speed by engaging and disengaging each clutch and brake as shown in the operation table of FIG. In FIG. 4, a circle indicates an engaged state, a circle indicates an engaged state during engine braking, and a blank indicates a released state.

As shown in the operation table of FIG. 4, the second
To change the speed between the third speed and the third speed, a clutch that changes the engaged / released states of the second brake B2 and the third brake B3 together.
Toe clutch shift. In order to smoothly perform this shift, the hydraulic circuit shown in FIG. 5 is incorporated in the hydraulic control device 18 described above.

In FIG. 5, reference numeral 70 indicates a 1-2 shift valve, reference numeral 71 indicates a 2-3 shift valve, and reference numeral 72 indicates a 3-4 shift valve. The communication state of each port of the shift valves 70, 71, 72 at each shift speed is determined by the respective shift valves 70, 71, 7
2 is shown below. In addition, the number shows each gear stage.

Of the ports of the 2-3 shift valve 71, a third brake B3 is connected through an oil passage 75 to a brake port 74 communicating with the input port 73 at the first speed and the second speed. An orifice 76 is provided in this oil passage, and a damper valve 77 is connected between the orifice 76 and the third brake B3. The damper valve 77 sucks a small amount of hydraulic pressure to perform a buffering action when the line pressure is suddenly supplied to the third brake B3.

Reference numeral 78 is a B-3 control valve, and the engagement pressure of the third brake B3 is directly controlled by this B-3 control valve 78. That is, the B-3 control valve 78 includes a spool 79, a plunger 80, and a spring 81 interposed therebetween, and an oil passage 75 is connected to an input port 82 opened and closed by the spool 79. Output port 8 that is selectively communicated with input port 82
3 is connected to the third brake B3. Further, the output port 83 is connected to a feedback port 84 formed on the tip side of the spool 79.

On the other hand, in the port 85 that opens at the location where the spring 81 is arranged, the port 86 that outputs the D range pressure at the third or higher speed of the 2-3 shift valve 71 is the oil passage 87. Are communicated via. Further, the control port 88 formed on the end side of the plunger 80 is
A linear solenoid valve SLU for the lockup clutch is connected.

Therefore, the B-3 control valve 78
Is configured such that the pressure regulation level is set by the elastic force of the spring 81 and the hydraulic pressure supplied to the port 85, and the higher the signal pressure supplied to the control port 88, the greater the elastic force of the spring 81. There is.

Further, reference numeral 89 in FIG. 5 denotes a 2-3 timing valve. The 2-3 timing valve 89 has a spool 9 having a small diameter land and two large diameter lands.
0, the first plunger 91, the spring 92 arranged between them, and the spool 90, and the first plunger 9
1 and a second plunger 93 arranged on the opposite side. An oil passage 95 is connected to an intermediate port 94 of the 2-3 timing valve 89, and this oil passage 95 is
Of the ports of the 2-3 shift valve 71, the port 96 is connected to the port 96 that is communicated with the brake port 74 at the shift speed of the third speed or higher.

Further, the oil passage 95 is branched midway to open a port 97 between the small diameter land and the large diameter land.
Is connected via an orifice. The port 98, which is selectively communicated with the port 94 at the intermediate portion, is the oil passage 9
It is connected to the solenoid relay valve 100 via 9. The lock-up clutch linear solenoid valve SLU is connected to the port opened at the end of the first plunger 91, and the second brake B2 is passed through the orifice at the port opened at the end of the second plunger 93. Connected.

The oil passage 87 is for supplying and discharging hydraulic pressure to and from the second brake B2, and a small diameter orifice 101 and an orifice 102 with a check ball are interposed in the middle thereof. Further, the oil passage 103 branched from the oil passage 87 has a large diameter orifice 10 provided with a check ball that opens when the pressure is exhausted from the second brake B2.
4 is interposed, and this oil passage 103 is connected to an orifice control valve 105 described below.

The orifice control valve 105 is a valve for controlling the exhaust pressure speed from the second brake B2, and the port 107 formed in the intermediate portion so as to be opened and closed by the spool 106 has the second brake B2.
The oil passage 103 is connected to a port 108 formed below the port 107 in the figure.

Port 1 to which the second brake B2 is connected
The port 109 formed on the upper side in the figure from 07 is a port that is selectively communicated with the drain port, and the port 109 is connected to the port 111 of the B-3 control valve 78 via an oil passage 110. It is connected.
The port 111 is a port that is selectively communicated with the output port 83 to which the third brake B3 is connected.

Of the ports of the orifice control valve 105, a control port 112 formed at the end opposite to the spring for pressing the spool 106 is connected to the port 114 of the 3-4 shift valve 72 through the oil passage 113. ing. This port 114 outputs the signal pressure of the third solenoid valve S3 at the shift speed of the third speed or lower, and the fourth speed.
It is a port for outputting the signal pressure of the fourth solenoid valve S4 at a shift speed higher than the high speed. Further, an oil passage 115 branched from the oil passage 95 is connected to the orifice control valve 105, and the oil passage 115 is selectively connected to the drain port.

Incidentally, the port 11 for outputting the D range pressure at the shift speed of the second speed or lower in the 2-3 shift valve 71.
6 through the oil passage 11 at the port 117 opening at the position where the spring 92 is arranged in the 2-3 timing valve 89.
8 are connected. Also 3-4 shift valve 72
Of these, a port 119, which is communicated with the oil passage 87 at a speed lower than the third speed, is connected to the solenoid relay valve 100 via an oil passage 120.

In FIG. 5, reference numeral 121 indicates an accumulator for the second brake B2, and reference numeral 122 indicates C.
A -0 exhaust valve is shown, and reference numeral 123 is an accumulator for the clutch C0. C-0
The exhaust valve 122 is a clutch C for applying the engine brake only in the second speed in the second speed range.
It operates so as to engage 0.

Therefore, according to the hydraulic circuit described above,
If the port 111 of the B-3 control valve 78 communicates with the drain, the engagement pressure of the third brake B3 can be directly regulated by the B-3 control valve 78, and the regulation level can be adjusted by the linear solenoid valve. SLU
Can be changed by If the spool 106 of the orifice control valve 105 is in the position shown in the left half of the figure, the second brake B2 can be communicated with the oil passage 103 through this orifice control valve 105, so that the large diameter orifice 104 is used. Exhaust pressure is possible and therefore the drain speed from the second brake B2 can be controlled.

In the above-mentioned automatic transmission, the second brake B2 is released and the third brake B3 is engaged at the second speed, and the second brake B2 is engaged and the third brake B3 is engaged at the third speed. Since the gears are engaged, the shift between the second speed and the third speed is a clutch-to-clutch shift in which the two brakes B2 and B3 are operated together. This clutch
The downshift from the third speed to the second speed of the two-clutch shift is achieved by releasing the second brake B2 and engaging the third brake B3. The shift usually occurs in the power-on state, so when the shift is output, first,
While reducing the engagement pressure of the second brake B2,
The engagement pressure of the brake B3 is kept low and the increase of the engine speed (the input speed to the automatic transmission) is promoted.
After that, the timing of the second speed synchronization is determined based on the change rate of the input rotation speed, and the third brake B is determined based on the determination result.
The engagement pressure of 3 is gradually increased (sweep up), and the second speed is achieved without causing a shock due to the smooth change of the input speed. On the other hand, even in the same downshift to the second speed, in the case of the interlaced shift from the fourth speed or the fifth speed, the following control is performed.

FIG. 6 is a flow chart showing an example of the control routine, and it is judged whether or not the judgment of the downshift from the fifth speed or the fourth speed to the second speed is established (step 1). . If a negative determination is made in step 1, the process returns without any particular control, and if an affirmative determination is made, shift output to the second speed is performed (step 2). This is for example a 2-3 shift valve 71 and
This is achieved by switching the 3-4 shift valve 72 to the second speed state. Note that step 1 corresponds to the jump shift determining means of the present invention.

In this case, the pressure is discharged from the second brake B2, and the torque capacity thereof gradually decreases. The engagement pressure of the third brake B3, which is engaged at the second speed, is adjusted to a low pressure such that the pack clearance is blocked by the B-3 control valve 78 and maintained at that pressure. Therefore, the input torque (turbine speed) NC0 gradually increases due to the decrease in the reaction torque applied to the sun gears 41 and 51. Further, in the case of downshifting from the fifth speed or the fourth speed to the second speed, and the change width of the input speed NC0 is large, the second clutch C engaged at the fifth speed and the fourth speed is engaged.
The exhaust pressure from 2 is rapidly performed, and the input rotational speed NC0 rapidly increases.

The input rotational speed NC0 which changes in this way is constantly monitored, and it is judged whether or not the input rotational speed NC0 is in a state satisfying the following expression following step 2 (step 3). .

NC0 ≧ No × ρ3 + ΔN1 where No is the output shaft speed, ρ3 is the gear ratio of the third speed, and Δ
N1 is a preset rotational speed. The meaning of this formula is that the input speed NC0 is the third speed synchronous speed (No x
.rho.3) is exceeded by .DELTA.N1 and therefore step 3 corresponds to the intermediate synchronization determining means of the present invention.

When a negative determination is made in step 3, the state in which the third brake B3 is on standby at a low pressure is continued. That is, the process returns to step 2. If an affirmative decision is made in step 3, the timing for synchronizing the input speed NC0 with the second speed is predicted (step 4). Specifically, it is determined whether the following formula is established.

(No × ρ2−NC0) / ΔNC0 ≦ α where ρ2 is the speed ratio of the second speed, ΔNC0 is the amount of change in the input rotational speed for each predetermined time, and α is the oil temperature, engine rotational speed or vehicle speed. It is a predetermined value that is mapped and set as a parameter. This expression means that the time required to reach the second speed synchronous rotation speed is α or less when the input rotation speed continues to change at the detected input rotation speed change rate ΔNC0. Therefore, this step 4 corresponds to the synchronization predicting means of the present invention.

If an affirmative decision is made in step 4, the input rotational speed NC0 reaches the shift state from the third speed to the second speed, which is a normal clutch-to-clutch shift, and the synchronization timing to the second speed is reached. Therefore, in this case, the sweep-up control for gradually increasing the engagement pressure PB3 of the third brake B3 to be engaged to set the second speed is started (step 5). ). Specifically, this control is executed by gradually increasing the signal pressure of the linear solenoid valve SLU to increase the pressure regulation level of the B-3 control valve 78.

On the other hand, if a negative determination is made in step 4, it is determined whether or not the input rotation speed NC0 has reached a low rotation speed by a predetermined rotation speed with respect to the second speed synchronous rotation speed. (Step 6). Specifically, this is (NC0 ≧ N
It is determined whether or not the expression of o × ρ2−ΔN2) is satisfied. This determination process is a determination process that determines a time point that is a predetermined time before the time point at which the synchronous rotation speed of the second speed is reached, by the rotation speed, and is a so-called guard operation. Therefore, if the affirmative judgment is made in step 6, the routine proceeds to step 5, where the third brake pressure PB3 is swept up, and if the negative judgment is made, the routine returns to step 2.

A time chart when the above control is performed is shown in FIG. That is, the shift determination from the fifth speed or the fourth speed to the second speed is established at time t0, and the shift output is performed at time t1 after a predetermined time. At this point,
The duty ratio of the linear solenoid valve SLU is set to a small value, and the third brake B3 is on standby at a low pressure. Further, since this shift is an interlaced shift in which the third speed is skipped, the input rotation speed is rapidly changed at the beginning of the shift in order to prevent a delay in the shift. After that, the input rotational speed NC0 gradually increases, and the timing of synchronization with the second speed is determined at time t2 when the synchronous rotational speed of the third speed exceeds ΔN1. Then, at time t3 when the input rotation speed NC0 increases by the rotation speed obtained by multiplying the input rotation speed NC0 by the predetermined value α, the sweep-up of the engagement pressure PB3 of the third brake B3 is started. In addition, the rotation change rate Δ
When the judgment of the synchronization time by NC0 is not established,
The sweep-up of the third brake pressure PB3 is started at time t4 when the input rotation speed increases by ΔN2 from the second speed synchronous rotation speed to ΔN2.

Therefore, according to the above control, the synchronization timing to the second speed is predicted after the input speed NC0 reaches the synchronous speed of the third speed adjacent to the shift speed, and the prediction result is obtained. Based on the engaging pressure P of the third brake B3 on the engaging side
It will control B3. Therefore, the rate of change of the input rotational speed at the beginning of the shift, which is different from the normal clutch-to-clutch shift, is not taken into the prediction of the synchronization timing, so that the prediction of the synchronization timing of the second speed becomes accurate. The third brake B, which is a friction engagement device on the engagement side based on the prediction result
The control of the engagement pressure PB3 of 3 becomes the same as the control at the time of the normal downshift from the third speed to the second speed, so that the shift shock becomes good.

In the above-described embodiment, the automatic transmission equipped with the gear train shown in FIG. 4 or the hydraulic circuit shown in FIG. 5 is targeted, so the fifth speed or the fourth speed to the second speed is applied.
Although the case of the interlaced shift to the high speed has been described, the present invention can be applied to a control device for an automatic transmission having a hydraulic circuit for a gear train other than the above-mentioned gear train or a hydraulic circuit, Therefore, similar control may be performed when performing an interlaced shift with a gear other than the second speed.

[0054]

As described above, according to the present invention,
In the case of the interlaced shift including clutch-to-clutch shift, the prediction of the synchronization timing to the shift stage after the shift is performed by using the second shift stage in which the rotation speed of a predetermined rotary element such as the input rotation speed is the shift speed after the shift. Since the synchronous prediction is executed after the synchronous speed of the first gear position adjacent to the gear position exceeds the second gear position side, the synchronization prediction is performed even if the gear shift pattern is an interlaced gear shift.
This is carried out in the same manner as the prediction of the synchronization timing in the case of a shift between normal adjacent shift speeds. Therefore, the prediction of the synchronization timing to the shift speed after the shift is accurate and the inconvenience such as the deterioration of the shock may occur. Can be prevented.

[Brief description of drawings]

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

FIG. 2 is a block diagram schematically showing a control system of an embodiment of the present invention.

FIG. 3 is a diagram mainly showing a gear train of the automatic transmission.

FIG. 4 is a diagram showing an operation table for setting each shift speed.

FIG. 5 is a diagram showing a part of a hydraulic circuit.

FIG. 6 is a flow chart schematically showing an example of a control routine for predicting a synchronization timing in the case of a downshift due to an interlaced shift to the second speed.

FIG. 7 is a time chart thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st friction engagement device 2 2nd friction engagement device 3 Rotating element 4 Automatic transmission 5 Interlaced shift determination means 6 Intermediate synchronization determination means 7 Synchronization prediction means

Claims (1)

[Claims] 1. When shifting from a first gear to a second gear by releasing a first friction engagement device and engaging a second friction engagement device, a second friction In the control device for the automatic transmission, the engagement device is pressure-increased from a low-pressure standby state by predicting a synchronous rotation timing to a second speed stage from a rotational speed change rate of a predetermined rotary element, An interlaced shift determining means for determining a shift to a second shift stage that has skipped over a shift stage, and a rotational speed of the rotary element at the time of the interlaced shift is a second shift stage rather than a synchronous rotational speed of the first shift stage. And an intermediate synchronization determining means for determining that the rotational speed of the rotating element has exceeded the synchronous rotational speed side of the first speed change step. When it is determined, the synchronization timing from the rate of change of the rotational speed of the rotary element to the second speed stage A control device for an automatic transmission, comprising: