JP3293456B2 - Control device for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission mounted on an automobile, and more particularly, to a shift control device in which a different shift is determined during a shift operation (multiple shift).

[0002]

2. Description of the Related Art Generally, in an automobile equipped with an automatic transmission, a first gear is engaged and a second friction is released, that is, a shift to a predetermined gear by so-called gripping is performed. During the speed change operation, one of the friction engagement elements is switched from engagement to release, and a shift to a speed different from the predetermined speed at which the third friction engagement element is engaged is determined. Sometimes. For example, during a shift operation from the third speed to the fourth speed by engaging a predetermined clutch (for example, C3 clutch) and releasing a predetermined brake (for example, B4 brake), releasing the predetermined clutch and different braking (for example, B5 brake) May be engaged to perform the speed change operation to the second speed.

Conventionally, in such a case, for example,
As shown in Japanese Patent No. 50621, the first shift command is issued, and the state in which the input / output rotational speed ratio at the gear set by the shift command becomes approximately 1.0 has continued for a predetermined time or more. It is determined that the operation to the speed change step is completed, and a second speed change command different from the first speed change command during the period from the first speed change command to the completion of the shift speed change is determined. Is issued, the shift operation based on the second shift command is not performed. That is, even if there is a second shift determination during the first shift operation, the second shift operation is prohibited until the first shift operation is completed. The timing of the gripping comes to prevent the engine from blowing up or abnormally lowering.

[0004]

In the above prior art,
Since the second shift is prohibited until the first shift operation ends, the shift time from the start of the first shift to the end of the second shift becomes longer.

[0005] Therefore, the present invention provides an automatic transmission which prevents the occurrence of a shift shock and shortens the shift time when the second shift is determined during the first shift operation as described above. It is an object of the present invention to provide a control device.

[0006]

According to the first aspect of the present invention, each of the sensors (11, 12, 1) based on a vehicle running condition is provided.
The hydraulic pressure control means (16, 17, 19) which receives the signals from (3, 15) and controls the hydraulic pressure of the plurality of predetermined frictional engagement elements to the hydraulic servos (27, 29, 30) respectively. In the control device for an automatic transmission having a control unit (U) that outputs a signal, when the control unit determines the second shift during the first shift operation based on a signal from each of the sensors, The second shift is a re-grip shift that engages a first frictional engagement element (for example, B5) and releases a second frictional engagement element (for example, C3 or B4). Is determined, the hydraulic pressure for the first frictional engagement element on the engagement side is activated by a servo so that the piston is stroked and the first frictional engagement element is in a state before torque transmission. Start and release when the servo activation is completed Having multiple shift control means (1) for outputting the oil pressure control signal to initiate a second release of the frictional engagement element hydraulic to be, the control device for an automatic transmission, characterized in that.

[0007]

According to a second aspect of the present invention, the first shift operation includes a plurality of hydraulic control stages (for example, a torque phase control, an inertia phase control, and a completion control).
At the same time as the servo activation of the hydraulic pressure in the shift, the hydraulic control of the first shift operation is performed according to each control stage at the time of the second shift determination.

According to a third aspect of the present invention, in the first shift operation (for example, 3-4 shift), a third friction engagement element (for example, C3) is engaged and a fourth friction engagement element is engaged. (For example, B4), and the third or fourth friction engagement element (C3 or B4) performs the second shift operation (for example, 4-2 shift or 3-2 shift).
And the second frictional engagement element on the release side.

According to a fourth aspect of the present invention, when the first shift operation (for example, 3-4 shift) at the time of the second shift determination (for example, 3-2 shift) is a torque phase, the second shift operation is performed. The hydraulic pressure for the third or fourth frictional engagement element (for example, B4) on the side that is the frictional engagement element is set to a predetermined pressure (P _H ) that holds the input torque at the start of the first shift. The predetermined pressure is maintained until the servo activation of the hydraulic pressure for the first frictional engagement element is completed (see FIG. 6).

According to a fifth aspect of the present invention, when the first shift operation (for example, 3-4 shift) at the time of the second shift determination (for example, 4-2 shift) is an inertia phase, the second shift operation is performed. The hydraulic control for the third or fourth frictional engagement element (for example, C3) on the side which is the frictional engagement element of the first step performs the first shift operation by terminating the servo activation of the hydraulic pressure for the first frictional engagement element. (See FIG. 7).

According to a sixth aspect of the present invention, when the first shift operation (for example, 3-4 shift) at the time of the second shift determination (for example, 4-2 shift) is a shift end state, The hydraulic pressure for the third or fourth frictional engagement element (for example, C3) on the side that is the second frictional engagement element is set to a predetermined pressure (P _H ) that holds the input torque at the end of the first shift. Then, the predetermined pressure is maintained until the servo activation of the hydraulic pressure for the first friction engagement element is completed (see FIG. 8).

According to a seventh aspect of the present invention, a signal from each of the sensors (11, 12, 13, 15) based on a vehicle running condition is inputted, and a hydraulic servo (2) of a plurality of predetermined friction engagement elements is inputted.
7, 29, 30), the control device for an automatic transmission having a control unit (U) for outputting a hydraulic control signal to a plurality of hydraulic control means (16, 17, 19) for controlling the hydraulic pressure. Is based on signals from the sensors,
When the second shift is determined during the first shift operation, when the second shift is determined, the piston engages the hydraulic pressure for the friction engagement element that operates in the second shift, and the second shift is determined. Multiple shift control that starts servo start so that the friction engagement element is in a state before torque transmission, and outputs the hydraulic control signal so as to start the second shift operation in a state where the servo start is completed. Means (1), the second
The input torque at the time of the shift determination is estimated, the second shift operation is started at a hydraulic pressure according to the input torque, and the input torque at the time of the second shift determination is Throttle opening (th
o) and the throttle opening (th
r), a correction value is calculated from the difference from
The automatic transmission control device is characterized in that the input torque that is the basis of the hydraulic control in the shifting operation is corrected.

[Operation] Based on the above configuration, when the second shift determination is made during the first shift operation, the first frictional engagement that operates as the engagement side in the second shift at the same time as the shift determination. The hydraulic pressure for the element starts the servo activation, and when the servo activation ends,
The release of the hydraulic pressure for the second frictional engagement element that is on the release side in the second shift is started.

The reference numerals in the parentheses are for comparison with the drawings, but do not limit the configuration of the present invention.

[0016]

According to the first aspect of the present invention, the servo activation of the hydraulic pressure for the engagement-side frictional engagement element of the second shift is started simultaneously with the determination of the second shift, so that the time lag is reduced accordingly. To reduce the shift time during multiple shifts,
After the servo is started, the release of the hydraulic pressure for the release-side friction engagement element of the second shift is started, so that the shift feeling is not impaired.

If the second shift is a clutch change shift and the shift operation is started at the same time, the engagement-side hydraulic pressure is servo-activated and the piston strokes, despite the release-side hydraulic pressure being discharged, and the timing is adjusted. Unnecessary engine blow-up or the like may occur, but as described above, the engagement-side hydraulic pressure is servo-activated before the start of the second shift operation. Since the operation is performed, it is possible to improve the timing at which the disengagement-side and engagement-side frictional engagement elements are grasped, thereby preventing the occurrence of a shift shock.

According to the second aspect of the present invention, the hydraulic control suitable for the first shift state is performed in parallel with the servo activation of the second shift, so that a good shift hydraulic pressure is always obtained regardless of the shift state. Control can be performed.

In the case of the first speed change operation and the reciprocating speed change,
According to the third aspect of the present invention, the engagement-side or release-side friction engagement element in the first shift is replaced by the release-side friction engagement element in the second shift. Thus, with a relatively simple configuration and control for hydraulically controlling each of the three hydraulic servos, it is possible to perform hydraulic control in which both the first and second shifts are performed by gripping.

According to the fourth aspect of the present invention, in the torque phase of the first shift, since the rotational change has not yet occurred, the first shift is stopped, and the torque is shifted to the release side in the second shift. The frictional engagement element is maintained at a predetermined pressure for maintaining the torque, and waits until the servo activation is completed, so that the second shift can be controlled quickly and quickly.

If the first shift operation is in the inertia phase at the time of the second shift determination, the second shift is immediately started.
The rotation changes due to the change in the hydraulic pressure applied to the disengagement side frictional engagement element, giving the driver an uncomfortable feeling. According to the present invention according to claim 5, the hydraulic control of the disengagement side frictional engagement element is performed. Is continued until the start of the servo, so that the change in the input rotation becomes smooth and the shift feeling can be improved.

Generally, a high oil pressure equivalent to the line pressure is supplied and held to the engagement side hydraulic servo after the shift is completed. According to the present invention, the second shift is determined after the shift is completed. In this case, since the predetermined hydraulic pressure sufficient for holding the torque is set and held in the engagement hydraulic servo, the second shift can be performed with good timing.

When the engine is in a transient state, the estimation of the engine torque involves a time delay in detecting an accurate engine speed. Therefore, it is necessary to directly estimate the input torque during the second shift operation. Is not preferable because it causes a response delay of the hydraulic control, but according to the present invention according to claim 7,
By adding a correction based on the difference in throttle opening based on the input torque in the first shift operation, it is possible to prevent a response delay in hydraulic control.

[0024]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a multiple speed change control according to the present invention.

FIG. 1 is a schematic diagram showing a control device for an automatic transmission to which the present invention can be applied. An electronic control unit U includes an engine speed sensor 11, a throttle opening sensor 12, an input speed of the automatic transmission. Electric signals from a (turbine rotation speed) sensor 13 and a vehicle speed (output rotation speed) sensor 15 are input. The electronic control unit U has a multiplex shift control means 1, which calculates and outputs it to the three linear solenoid valves 16, 17 and 19 respectively.

Linear solenoid valves 16, 17, 19
Constitutes a hydraulic control means, and each of the input ports 16 based on a current value (a hydraulic control signal) from the control unit U.
a, 17a, and 19a are regulated and output to the output ports 16b, 17b, and 19b, and the hydraulic pressure from each output port is applied to the control oil chambers of the shift pressure control valves 20, 21, and 22, respectively. Acts on 20a, 21a, 22a. These control valves 20, 21, 22 are connected to the input ports 20b, 21b, 22b based on the hydraulic pressures of the control hydraulic pressures.
Output line 20c, 21c, 22
c, and the controlled hydraulic pressure acts on hydraulic servos 27, 29, and 30 that operate predetermined frictional engagement elements via predetermined shift valves 23, 25, and 26, respectively.
Specifically, the hydraulic servo 27 is a C3 clutch hydraulic servo engaged at the fourth and fifth speeds, and the hydraulic servo 29 is engaged at the first, second, and reverse speeds. The hydraulic servo for brake is a hydraulic servo 30. The hydraulic servo 30 is a hydraulic servo for B4 brake engaged at the third speed.

Next, a description will be given of the hydraulic control in which the downshift to the second speed is determined during the upshift operation from the third speed to the fourth speed with reference to the flowcharts of FIGS.

First, as shown in FIG. 2, the upshift operation from third gear to fourth gear will be described. When a shift command from third gear to fourth gear is determined (S1) (shift control starts), a timer is started. Starts timekeeping (S2), and servo start control (S3) is performed.
If the target gear is not at the second speed (S4), the servo activation control is continued for a predetermined time tSA (S5). As a result, as shown in FIGS. 6, 7, and 8, the engagement side oil pressure _PC3 is supplied to the C3 clutch hydraulic servo 27, which is a friction engagement element engaged at the fourth speed, and the engagement side oil pressure servo Is filled with oil, and the releasing hydraulic pressure P _B4 of the B4 brake hydraulic servo 30, which is a friction engagement element released at the fourth speed, is released to a predetermined hydraulic pressure. In the servo start control, the engagement side and release side hydraulic pressures are P _C3 , B _B4
Is maintained at a predetermined pressure which is equal to or higher than the piston stroke pressure and does not cause a rotation change of the input shaft (that is, does not transmit torque).

Next, the turbine (input) torque is estimated (S6). The turbine torque is obtained from a map to determine the engine torque based on the throttle opening and the engine speed, further calculating the speed ratio from the input / output speed of the torque converter, and calculating the torque ratio from the map using the speed ratio.
Then, it is obtained by multiplying the engine torque by the torque ratio. Further, a target target rotation speed change rate (target rotation acceleration) ω ′ at the start of the rotation change of the input shaft rotation speed is calculated (S7).

Then, torque phase control is performed (S
8). That is, as shown in FIG. 8, the engagement side oil pressure P _C3 is set to a target engagement oil pressure P _T immediately before the start of a change in the rotation of the input rotation speed calculated based on the turbine torque (immediately before the inertia phase) and a preset value. The sweep-up is performed based on the gradient (first sweep angle) determined by the set time.
Further, when the engagement (target) oil pressure P _T is reached, the sweep is performed at a gentler gradient than the first sweep angle by the oil pressure change amount Pω calculated from the target rotation speed change rate ω ′. Then, the second sweep-up is continued until the rotation change of the input shaft rotation speed reaches a shift start determination rotation speed that can be detected by the input shaft rotation speed sensor 13. Therefore, the point at which the hydraulic pressure amount Pω (the second sweep-up amount) for the inertia torque calculated from the target rotational speed change rate ends is the shift start. Generally, the time point is determined by the input engine torque and the engagement torque. The load of the vehicle driving force determined by the torque capacity of the side frictional engagement element is in a balanced state, and the engagement side frictional engagement element is sliding while transmitting torque by friction until the shift start determination. In the torque phase where there is no change in rotation and only the torque share changes. Thereafter, the torque capacity of the friction engagement element increases to exceed the engine torque, and an inertia phase in which the engine speed starts to decrease (the input shaft speed changes).

On the other hand, in the torque phase control, the release hydraulic pressure P _B4 is released at a predetermined gradient as shown in FIG. 8 (sweep down). It becomes loose and the brakes do not slip due to the reaction force. Then, in the torque phase control, it is determined again whether or not the target gear is the second speed (S9).

After the start of the shift is determined (S
10), inertia phase control is performed (S11). In the inertia phase control, the engagement-side hydraulic pressure _PC3 is controlled by the input shaft speed sensor 1 such that the rotation speed of the input shaft continuously changes from the target rotation speed change rate ω 'to a predetermined target rotation speed.
The feedback control is performed while monitoring the detected value of No. 3. On the other hand, as shown in FIG. 8, immediately after the shift start is determined, the release-side hydraulic pressure P _B4 is released at once with a steep gradient, and the brake B4 is released to enter the fourth speed state. Then, during the inertia phase control, it is determined again whether or not the target gear is in the second speed (S12), and the inertia phase control is continued until the shift is completed (S13).

Further, completion control is performed (S15) when the timer measures a predetermined time (S14). Also,
In the completion control, it is determined again whether the target gear is in the second speed (S16), and when a timer elapses a predetermined time from the end of the shift (S17), the shift control ends (S18). The servo start control (S3), the torque phase control (S8), the inertia phase control (S11), and the completion control (S15) constitute a plurality of hydraulic control stages in a 3-4 shift (first shift) operation.

Thus, the engagement-side hydraulic pressure gradually increases, the torque capacity of the friction engagement element increases, and the gear shift ends when the difference between the input and output rotational speeds of the friction engagement element disappears. Further, the slightly remaining stroke of the cushioning spring of the engagement-side friction engagement element is compressed and the hydraulic pressure of the engagement-side hydraulic servo becomes equal to the line pressure,
The shift control ends. At this time, the release hydraulic pressure P
_B4 is drained and brake B4 is released.

On the other hand, the downshift operation from the third gear to the second gear is as follows.
As shown in FIG. 3A, first, based on the 3-2 shift determination, shift control is started (S20), and then standby control is performed (S21). Thereby, as shown in FIG.
Hydraulic servo 29 for B5 brake is in the three-speed state frictional engagement element in the released state (engagement side) is, with the shift control start (shift command), similarly to the engagement side hydraulic pressure P _C3 The servo is started so that the piston is stroked and the state before the torque is transmitted, and the hydraulic servo for B4 brake, which is the frictional engagement element (disengagement side) in the engaged state, starts shifting control. Accordingly, the pressure is reduced from the line pressure to a predetermined pressure so that the state before the torque transmission is performed.

After the elapse of the predetermined time, the turbine torque is estimated in the same manner as described above (S22), the target rotational speed change rate is calculated (S23), and the initial shift control is performed (S24). As a result, the release-side hydraulic pressure becomes the predetermined engagement hydraulic pressure P calculated based on the input (turbine) torque.
_T , that is, the engagement hydraulic pressure _PT immediately before the start of the rotation change of the input rotation speed, is reduced to the initial shift control state. Furthermore, from the predetermined engagement pressure P _T state, in the same manner as described above, it is swept down on the basis of the oil pressure variation Pω calculated by the target speed change ratio omega 'when the input shaft rotation speed of the rotation change start. In addition, the engagement side hydraulic pressure P _B5 is swept up in accordance with the sweep down.

The sweep-down of the release-side hydraulic pressure causes an inertia phase to occur, whereby the engine speed is increased, and the inertia phase control is performed to gradually reduce the hydraulic pressure based on the change in the input shaft speed ( S25). As a result, the engine speed increases and the automatic transmission 2
When the speed level is reached, the shift is completed, and thereafter, drainage is performed until the disengagement side oil pressure P _B4 becomes zero, and the engagement side oil pressure P _B5 is increased to the line pressure, whereby the shift control ends. Thus, the completion control is performed after the end of the shift (S2).
6), the shift control ends (S27).

The downshift operation from the 4th speed to the 2nd speed is as follows.
As shown in FIG. 3B, first, based on the 4-2 shift determination,
The shift control is started (S30). The 4-2 shift control is the same as the 3-2 shift control except that the disengagement side frictional engagement element is a C3 clutch (accordingly, the hydraulic servo 27), and is similar to the steps S21 to S27. The standby control S31, the turbine torque estimation S32, the inertia phase control S35, the completion control S36, and the shift control end (S37).

Then, in the flowchart of FIG.
When the target gear is determined (S9) during the torque phase control (S8), the second gear is determined, that is, at the stage before the start of the 3-4 shift (before the inertia phase), the shift to the second gear is performed. When a downshift command is determined, hydraulic control is performed as shown in FIGS. 4 (a) and 6. First, as shown in FIG. 6, the release side hydraulic pressure P _B4 sweeps down and the engagement side hydraulic pressure P _C3 sweeps up. When the shift to the first gear is determined, timing of the timer is started (S40), and the (release side) oil pressure P _B4 of the B4 brake hydraulic servo 30 that is released in the fourth and second gears is set to a standby state. (S2
1), that is, stand by at a predetermined oil pressure P _H that holds the input torque at the third speed, and the predetermined oil pressure P _H is held until the servo activation is completed, and is engaged at the fourth speed. Of clutch hydraulic servo 27 (engagement side)
The hydraulic pressure _PC3 is released (S41). That is, the state is returned to the 3-4 speed shift control start state.

Then, the hydraulic pressure P _{B5 of the} B5 brake hydraulic servo 29 to be engaged in the second speed is servo-activated (S42). That is, once the hydraulic pressure sufficient to start the piston stroke is supplied, and the hydraulic pressure P _B5 is controlled such that the piston is in a state immediately before the stroke and torque transmission is performed. The timer continues for a predetermined time tSA from the start of the timer (S43).

When the servo activation of the hydraulic pressure P _B5 is completed, 3-
A correction for the change in the throttle opening is added to the turbine torque value estimated at the start of the fourth shift, and the turbine torque is estimated (S44). The correction of the turbine torque is corrected by estimating the amount of change from the turbine torque in step S6 with respect to the current turbine torque. The estimation of the amount of change in the torque is based on the throttle opening th at the time of the torque calculation. From the current throttle opening thr, FIG. 9 (a)
Is determined by a map as shown in FIG. As shown in FIG. 9B, the map shows that the difference Δθ between the two throttle openings is plus (rightward), that is, the current throttle opening is 3-4.
If it is larger than the throttle opening at the time of calculating the shift (thr
> Tho), the same current throttle opening (for example, thr
= 60 [%]), the turbine torque correction value ΔT is set to be large, and when the throttle opening difference Δθ is minus (tho> thr), the turbine torque correction amount ΔT becomes small. It is set as follows. This is because when the current throttle opening thr is returned with respect to the throttle opening at the time of calculation, the hydraulic pressure is excessively reduced, thereby preventing the downshift operation from proceeding early and causing a shift shock. It is.

The estimation of the engine torque based on the change in the throttle opening in step S44 is because it is difficult to directly estimate the actual engine torque in a transient state in which the engine torque changes. In a state in which the difference between the input torque of the automatic transmission determined by the torque capacity of the engagement element and the actual engine torque acts on the engine as a load (the state of being rotated by the transmission), the correct engine speed is not delayed. This is because it is difficult to detect.

Then, the target hydraulic pressure _PT of the release hydraulic pressure P _B4 is calculated from the turbine torque obtained by adding the above correction to the turbine torque value obtained in step S6. In this state, the target hydraulic pressure _PT shown in FIG. The control is shifted to the two-shift control to calculate the target rotational speed change rate in step S23, whereby the downshift operation from the initial shift control (S24) is performed. That is, the disengagement side oil pressure P _B4 is released based on the target oil pressure and the target rotation change rate, the engagement side oil pressure P _B5 rises in accordance with the disengagement oil pressure, and the input shaft rotation speed _NT changes. In the inertia phase (3-2 shift start), the release hydraulic pressure P at a predetermined gradient based on the rotation change.
_B4 is released and the engagement side hydraulic pressure P _B5 is increased. When the speed difference of the B5 brake disappears and the B4 brake is released, the 3-2 shift is completed. Finally, the release hydraulic pressure P _B4 is completely drained, and the engagement hydraulic pressure P _B5 is reduced to the line pressure. Is completed (S2
6), the shift control ends.

As shown in FIG. 6, when the shift to the second speed is determined before the start of the 3-4 shift, the shift to the second speed is simultaneously determined with the engagement side at the second speed. The servo is started at the hydraulic pressure _PB5 , and the 3-4 shift is returned to the state before the start of the shift, and the hydraulic control of the 3-2 shift is performed from here. Accordingly, the input (turbine) rotation speed increases from the start of the 3-2 shift and enters the second speed state.

Also, during the servo start control of the 3-4 shift control (S3), the target gear speed is determined in step S4.
When it is determined that the vehicle is in the second gear, as shown in FIG. 4B, steps S40, S41, S42, S42 similar to those in FIG.
43 is performed. Then, the servo activation state (S3
), No change in torque occurs, so that the 3-2 shift control is performed from the estimation of the turbine torque in step S22, and thereafter, the 3-2 shift control is similarly performed.

Next, in the flowchart of FIG.
Determination of target gear during inertia phase control (S11) (S11)
If it is determined that 12) is a downshift to the second speed, control is performed as shown in FIGS. First, a timer is started (S50), and the inertia phase control of the 3-4 shift is continued (S51). At the same time as the determination of the shift to the second speed, the third and fourth speeds are in the released state.
Servo start of the engagement side oil pressure P _B5 to the brake hydraulic servo 29 is performed (S52), and in the 3-4 speed inertia phase control and servo start, the servo start end time tSA elapses (S53). Alternatively, the process is continued until the end of the 3-4 shift (S54).

When the servo activation is completed, similarly to step S44, the turbine torque value estimated at the start of the 3-4 shift is corrected by the change in the throttle opening to estimate the turbine torque (S55). And three
(4) The target rotational speed change rate calculated before the start of the shift (see S7) is multiplied by (-1) to obtain a new target rotational speed change ratio (S56).

The target oil pressure _PT is calculated from the turbine torque obtained by adding the above correction to the turbine torque value obtained in step S6, and the target rotational speed change rate obtained in step S8 is multiplied by (-1). That is, the hydraulic pressure change amount Pω is calculated by setting the gradient to a downward gradient, whereby the downshift operation from the initial shift control (S34) of the 4-2 shift control of FIG. 3B is performed. This is because when the rotation changes, the estimation of the engine torque is difficult because it is difficult to detect an accurate engine speed without time delay because the engine is in a transient state. This is because it is difficult to detect the gear ratio of the automatic transmission in the state and set the target rotation speed change rate at the start of the rotation change of the new input rotation speed. Then, the inertia phase control (S35) and the completion control (S36) described above are performed, and the shift control ends (S37).

In this manner, when the shift to the second speed is determined during the 3-4 shift, as shown in FIG. 7, the engagement-side hydraulic pressure P _B5 is servo-activated simultaneously with the shift determination. At the same time, the 3-4 shift operation is continued as it is, and when the servo activation ends, the 4-2 shift control is performed.
Accordingly, the input (turbine) rotation speed _NT temporarily decreases with the shift to the fourth speed, and increases with the shift to the second speed.

Also, during completion control during 3-4 shift control (S
When the target gear position determination (S16) in 14) determines the second speed, hydraulic control is performed as shown in FIGS. First, since the 3-4 shift has been completed, the B4 brake hydraulic pressure P _B4 released at the fourth speed is held in the released state, and is engaged at the fourth speed and released at the second speed. The C3 clutch (disengagement side) hydraulic pressure P _C3 is held at a predetermined hydraulic pressure P _H that holds the input torque in the fourth speed (S
57) And the predetermined pressure is maintained until the servo activation is completed.

Simultaneously with the determination of the second speed, the B5 brake (engagement side) hydraulic pressure P _B5 engaged in the second speed is servo-activated (S58). Then, the predetermined time tSA
Has elapsed and the servo activation of the engagement side hydraulic pressure P _B5 is completed (S59). As in steps S44 and S55, 3
-4 The turbine torque is estimated by adding a correction for the change in the throttle opening to the turbine torque value estimated at the start of the shift (S60), and then the calculation of the target rotational speed change rate shown in FIG. 3B (S33). Then, the 4-2 shift control is performed. That is, the target pressure P _T based on the input torque value has been corrected in the step S60 is calculated, hydraulic variation Pω from the target speed change rate is calculated, predetermined gradient disengagement hydraulic pressure P _C3 This At the same time, the engagement side oil pressure P _B5 rises at a predetermined gradient in accordance with the release side oil pressure.

Then, the fact that the 4-2 shift has started is as follows.
When the input rotational speed sensor 13 detects the input, the inertia phase control S35 is performed, the release hydraulic pressure _PC3 is swept down at a gentle gradient, the engagement hydraulic pressure _PB5 is increased, and the brake B5 is locked. When the vehicle enters the high-speed state (the shift is completed), the completion control is performed (S36), and the engagement side hydraulic pressure P _{B5 is set.}
, And the release hydraulic pressure _PC3 is drained, and the shift control ends (S37).

Thus, when the shift to the second speed is determined after the completion of the 3-4 shift, the oil pressure _PC3 on the releasing side becomes:
Outputting a hydraulic pressure P _H to hold the current turbine torque,
This state is maintained until the servo activation end of the hydraulic P _B5 as the engagement side, after the servo activation completion, 4-2 shift control is performed. Accordingly, the input (turbine) rotational speed _NT temporarily decreases when the vehicle enters the fourth speed state, and after maintaining this state, increases as the speed is changed to the second speed.

In the above-described embodiment, the case where the shift to the second speed is determined during the 3-4 shift is described. However, the present invention is not limited to this, and the control is similarly performed in the case of the downshift of another upshift. The same control is performed when a further downshift is determined during the downshift operation.

For example, as shown in FIG. 10, when the shift to the second speed is determined during the 4-3 shift, the shift is determined to be 4-3.
If the shift is started (during the inertia phase control), the C3 clutch hydraulic pressure P _C3 released at the third speed continues to sweep down, and the B4 brake hydraulic pressure P _B4 engaged at the third speed sweeps up. continue. At the same time as the determination of the second speed, the B5 brake hydraulic pressure P _{B5 serving as the} engagement-side hydraulic pressure is servo-activated, and during the servo activation,
The three shift control is continued. Further, immediately after the start of the servo, the hydraulic pressure P _B4 is released, the release hydraulic pressure PC ₃ is swept down, and the engagement hydraulic pressure P _B5 is swept up, so that the 3-2 shift control is performed. In this state, the input (turbine) rotational speed _NT increases from the fourth speed to the third speed, and then increases to the second speed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a control device of an automatic transmission to which the present invention can be applied, wherein (a) shows an electronic control device and (b) shows a hydraulic control device.

FIG. 2 is a flowchart relating to 3-4 shift control.

FIG. 3A is a flowchart related to 3-2 shift control, and FIG. 3B is a flowchart related to 4-2 shift control.

FIG. 4A is a flowchart based on a shift determination to a second gear during torque phase control, and FIG. 4B is a flowchart based on a shift determination to a second gear during servo activation.

FIG. 5 shows a state during inertia phase control and completion control.
9 is a flowchart for determining a shift to a speed position.

FIG. 6 is a time chart related to hydraulic control when a shift to the second speed is determined in the torque phase during the 3 → 4 shift operation.

FIG. 7 is a time chart related to hydraulic control when a shift to the second speed is determined in the inertia phase during the 3 → 4 shift operation.

FIG. 8 is a time chart relating to hydraulic control in a case where a determination is made for a second speed after a shift is completed during a 3 → 4 shift operation.

FIG. 9 is a diagram showing correction of input torque, where (a) shows 1 → 2;
FIG. 7 is a table showing a correction value of input torque based on a throttle opening in a shift operation and a throttle opening when shifting to first speed is determined, and FIG. 4B is a diagram showing a change in the correction value due to a difference between the two throttles.

FIG. 10 is a time chart related to the hydraulic control when the shift to the second speed is determined during the inertia phase control of the 4-3 shift control.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Multiple speed change control means 11 Engine speed sensor 12 Throttle opening sensor 13 Input speed sensor 15 Vehicle speed sensor 16 Hydraulic control means (linear solenoid valve) 17 Hydraulic control means (shift pressure control valve) 20 Hydraulic servo U (electronic) control Department

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akechi Suzuki 10 Takane, Fujii-machi, Anjo, Aichi Prefecture Inside Aisin AW Co., Ltd. (72) Inventor Hiroshi Tsutsui 10 Takane, Fujii-cho, Anjo, Aichi Prefecture・ AW Co., Ltd. (56) References JP-A-6-346962 (JP, A) JP-A-2-46352 (JP, A) JP-A-5-203037 (JP, A) JP-A-6-346 280981 (JP, A) JP-A-6-346969 (JP, A) JP-A-7-259982 (JP, A) JP-A-9-26023 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (7)

(57) [Claims] A control unit which receives signals from each sensor based on a vehicle running condition and outputs a hydraulic control signal to a plurality of hydraulic control means for controlling hydraulic pressure of a plurality of predetermined frictional engagement elements to a hydraulic servo. In the control device for an automatic transmission, the control unit is configured to perform a first control based on a signal from each of the sensors.
If the second shift is determined during the shifting operation of the second gear, the second shift is a re-grip shift that engages the first frictional engagement element and releases the second frictional engagement element, When the second shift is determined, the hydraulic pressure for the first frictional engagement element on the engagement side becomes a state before the piston is stroked and the first frictional engagement element transmits torque. Start the servo start, and in the state where the servo start is finished
A control device for an automatic transmission, comprising: a multiple shift control unit that outputs the hydraulic pressure control signal so as to start releasing the hydraulic pressure for the second frictional engagement element on the release side . 2. The first shift operation includes a plurality of hydraulic control stages. The first shift operation includes a plurality of hydraulic control stages. depending performing hydraulic control of the first shift operation, the control system for an automatic transmission according to claim 1. 3. The first speed change operation is a grip change speed in which a third frictional engagement element is engaged and a fourth frictional engagement element is released, and the third or fourth frictional operation is performed. engagement element is a second frictional engagement element to be released side in the second shift operation, the control system for an automatic transmission according to claim 2, wherein. 4. The method according to claim 1, wherein the first shift is determined at the time of the second shift determination.
When the shift operation is in the torque phase, the third or fourth friction engagement element hydraulic pressure on the side that is the second friction engagement element is maintained at the input torque at the start of the first shift operation. 4. The control device for an automatic transmission according to claim 3 , wherein the predetermined pressure is set, and the predetermined pressure is maintained until the servo activation of the hydraulic pressure for the first friction engagement element is completed. 5. The method according to claim 1, wherein the first shift is determined at the time of the second shift determination.
When the shift operation of the second frictional engagement element is the inertia phase, the hydraulic control for the third or fourth frictional engagement element on the side that is the second frictional engagement element performs the first shift operation by the first frictional operation. The control device for an automatic transmission according to claim 3 , wherein the control is continued until the servo activation of the engagement element hydraulic pressure is completed. 6. The first shift control device according to claim 1, wherein the first shift determination is performed when the second shift is determined.
When the shift operation is in the shift end state, the hydraulic pressure for the third or fourth friction engagement element on the side that is the second friction engagement element is held at the input torque at the end of the first shift operation. 4. The control device for an automatic transmission according to claim 3 , wherein the predetermined pressure is set to a predetermined value, and the predetermined pressure is maintained until the servo activation of the hydraulic pressure for the first friction engagement element is completed. 7. A control unit that receives a signal from each sensor based on a vehicle running situation and outputs a hydraulic control signal to a plurality of hydraulic control units that control hydraulic pressures of hydraulic clutches of a plurality of predetermined frictional engagement elements. In the control device for an automatic transmission, the control unit is configured to perform a first control based on a signal from each of the sensors.
When the second shift is determined during the shift operation of the second gear, when the second shift is determined, the hydraulic pressure for the friction engagement element that operates in the second shift is moved by the piston and the friction A multiplex shift control means for starting servo start so that the combined element is in a state before transmitting torque, and outputting the hydraulic control signal so as to start the second shift operation in a state where the servo start is completed. Estimating the input torque at the time of the second shift determination, starting the second shift operation with a hydraulic pressure according to the input torque, and the input torque at the time of the second shift determination is A throttle opening serving as a basis for hydraulic control in the first shift operation;
A correction value is calculated from a difference from the throttle opening at the time of the second shift determination, and an input torque serving as a basis for hydraulic control in the first shift operation is corrected using the correction value. Control device for automatic transmission.