JPS6184461A - Control device of automatic speed change gear - Google Patents

Abstract

PURPOSE:To prevent a speed change shock by delaying the generation of a lock up release by signal a time set according to the change rate of the rotation al frequency if the rotational frequency change condition of an engine output shaft is upward tendency when a shift-up signal is generated in the lock up state. CONSTITUTION:The above control device is adapted to intermittently operate a lock up mechanism A provided on a torque converter by controlling lock up electromagnetic means B and operate a geared speed change mechanism C by controlling speed change electromagnetic means D. In this case, when a shift up signal CP is output from speed change control means E, according to an output of rotational frequency change condition detection means G, if the rotational frequency of an engine output shaft is downward tendency, a lock up release signal Cq' is output in synchronization with outputting of the signal CP, and if it is upward tendency, outputting of the lock up release signal Cq' is delayed by lock up release timing adjust means F. The delay time of outputting the signal Cq' is set as time corresponding to the change rate of the rotational frequency by timer means H.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for an automatic transmission that reduces shift shock while preventing engine revving during upshifting.

(Prior Art) Generally, as an automatic transmission, one configured by combining a torque converter and a multi-stage gear type transmission mechanism having a gear mechanism such as a planetary gear mechanism is widely used. For speed change control in such automatic transmissions, a hydraulic mechanism is usually adopted, and the hydraulic circuit is switched using an electromagnetic switching valve.
As a result, frictional elements such as brakes and clutches, which are hydraulic actuators attached to the multi-gear transmission mechanism, are actuated as appropriate to switch the engine power transmission system and obtain a desired gear position. In order to switch the hydraulic circuit using an electromagnetic switching valve, an electronic control device detects that the vehicle's running state has exceeded a predetermined shift line, and an electromagnetic control device is activated by a shift up signal or a shift down signal from this device. It is customary to selectively operate a type switching valve, thereby switching the hydraulic circuit and changing speed.

In an automatic transmission having this torque converter,
Since slipping of the torque converter cannot be avoided, many engines are equipped with a lock-up mechanism to directly connect the engine output shaft and the output shaft of the torque converter in order to improve fuel efficiency. This lock-up mechanism performs lock-up (direct connection) or lock-up release by controlling the supply of hydraulic pressure to a hydraulic actuator associated with the lock-up mechanism using a lock-up electromagnetic means. This lock-up or lock-up release is usually performed by an electronic control device outputting a lock-up signal or a lock-up release signal to the lock-up electromagnetic means based on predetermined lock-up characteristics. .

As described above, in an automatic transmission having a lock-up mechanism, in order to avoid a large shock caused by shifting while the gear is in the lock-up state, as shown in Japanese Patent Application Laid-open No. 56-39354, even when the gear is in the lock-up state, During gear shifting, control is generally performed in which this lock-up is temporarily released and torque fluctuations (engine speed differences) caused by gear shifting are absorbed by the torque converter. Recently, research has begun to focus on the timing of releasing lock-up, with the assumption that the lock-up is released once during a gear shift, in order to obtain an even better shift feeling. There is.

As shown in Japanese Unexamined Patent Publication No. 56-127856, a method of devising such lock-up release timing takes into consideration the fact that up-shifts are often performed during acceleration, and when shifting up, the lock-up release timing is improved. In order to prevent the engine from revving up, a system has been proposed in which a lock-up release signal is output a certain period of time after the shift-up signal is output. In other words, the time lag between the output of the shift-up signal and the actual shift-up (response delay of the transmission hydraulic system) is usually larger than the time lag between the lock-up release signal and the actual lock-up release. If the release signal is output in synchronization with the shift-up signal, the lock-up will be released before the shift-up is actually performed and the engine load will be reduced, so if the shift-up is performed during acceleration, the engine will not rev up. However, by delaying the lock-up release signal output from the shift-up signal output as in the above-mentioned publication, this engine revving can be suppressed.

However, as described above, if the lock-up release signal output is simply delayed for a certain period of time than the shift-up signal output, the shift shock may become large depending on the driving mode at the time of up-shifting, and the engine may still rev up.

This problem may occur. To elaborate on this point,
For example, if we consider a case where an upshift is performed when transitioning from acceleration to constant speed driving, at this time the engine speed changes due to the gear shift as the engine speed tries to decrease (shift shock occurs). shows a favorable phenomenon such as However, delaying the release of lock-up while the engine speed is decreasing means that the drive wheels (inertia of the vehicle) force the engine to rotate in the locked-up state, which prevents the engine speed from decreasing. As a result, the difference between the engine speeds before and after the upshift becomes large, ie, the shift shock becomes large.

Furthermore, the degree of engine revving varies depending on the size of the throttle opening, etc., but if the delay time of the lock-up release signal output is kept constant as in the above publication, the degree of engine revving will vary. Therefore, it is impossible to sufficiently prevent the engine from racing during upshifting.

(Object of the invention) The present invention has been made in consideration of the above circumstances, and
To provide a control device for an automatic transmission that can more reliably alleviate shift shock and prevent engine revving during upshifting, and provides better shift feeling.

(Structure of the Invention) The present invention basically focuses on the fact that it is possible to accurately determine whether or not engine revving occurs by observing the state of change in engine speed during upshifting. It was done by That is, when the engine speed tends to increase, at which engine speed is likely to occur, the lock-up release signal is output a predetermined time rm later than the shift-up signal output, while at the same time, when the engine speed is at a rate at which engine speed does not occur, When the number is on a downward trend, the lock-up release signal output is set as the shift-up signal output so that the engine speed decreases more smoothly and the difference in engine speed between before and after the upshift is reduced. This should be done synchronously. The predetermined time period is set to a length corresponding to the rate of change in engine speed in order to cope with the degree of engine revving.

Specifically, as shown in FIG. 1, a torque converter connected to an engine output shaft, a gear type transmission mechanism connected to the output shaft of the torque converter, and a connection between the engine output shaft and the output shaft of the torque converter. a lock-up mechanism for controlling the supply of pressure fluid to the fluid-type actuator that performs a speed-change operation of the gear-type transmission mechanism; a lock-up electromagnetic means for controlling supply; a shift control half-recess for outputting a shift up signal or a shift down signal to the shift electromagnetic means based on a predetermined shift characteristic; and a predetermined lock-up characteristic. lock-up control means for outputting a lock-up signal or a lock-up release signal to the lock-up electromagnetic means based on the lock-up electromagnetic means; a rotation speed change state detection means for detecting a state of change in the rotation speed of the engine output shaft; When a shift-up signal is output to the speed-changing electromagnetic means, if the rotation speed of the engine output shaft is on a downward trend based on a signal from the rotation speed change state detection means, it is synchronized with the output of the shift-up signal. lock-up release timing adjusting means for outputting a lock-up release signal with a predetermined time delay from the output of the shift-up signal when the rotational speed of the engine output shaft is on an upward trend; and timer means for setting the length according to the rate of change in engine speed.

(Example) Examples of the present invention will be described below based on the attached drawings.

In FIG. 2, which shows a cross section of a mechanical part and a hydraulic control circuit of an electronically controlled automatic transmission, the automatic transmission AT includes a torque converter IO, a multi-gear transmission mechanism 20, a torque converter 10, a multi-gear transmission mechanism 20, and an overdrive planetary gear transmission mechanism 50 disposed between the two.

The torque converter 10 includes a pump 11 coupled to an engine output shaft l, a turbine 12 disposed opposite the pump 11, and a stator 13 disposed between the pump 11 and the turbine 12. is connected to the converter output shaft 14. A lock-up clutch 15 is provided between the converter output shaft 14 and the pump 11.
is installed. This lock-up clutch 15 is
The hydraulic pressure circulating within the torque converter 10 constantly urges the engagement direction, that is, the direction of locking up (directly connecting) the engine output shaft l and the torque converter output shaft 14, and the opening hydraulic pressure supplied from the outside It is kept open.

The multi-stage gear transmission mechanism 20 has a front planetary gear mechanism 21 and a rear planetary gear mechanism 22, and the sun gear 23 of the front planetary gear mechanism 21 and the sun gear 24 of the rear planetary gear mechanism 22 are connected via a connecting shaft 25. λ is. The input shaft 26 of the multi-stage gear transmission mechanism 20 is connected to the connecting shaft 25 via the front clutch 27 and to the internal gear 29 of the front planetary gear mechanism 21 via the rear clutch 28. Connecting shaft 25 or sun gear 23.2
4 transmissions, 7-72 degrees, 1 forward gear 30 are provided. Planetary carrier 31 of the front planetary gear mechanism 21 and internal gear 3 of the rear planetary gear mechanism 22
3 is connected to the output shaft 34, and a rear brake 36j and a one-way clutch 37 are interposed between the planetary carrier 35 of the rear planetary gear mechanism 22 and the transmission case.

In the overdrive planetary gear transmission mechanism 50,
A planetary carrier 52 that rotatably supports the planetary gear 51 is connected to the output shaft 14 of the torque converter IO, and the sun gear 53 is connected to the internal gear 55 via a direct coupling clutch 54. An overdrive brake 56 is provided between the sun gear 53 and the transmission case, and the internal gear 55 is connected to the input shaft 26 of the multi-gear transmission mechanism 20.

The multi-gear transmission mechanism 20 is of a conventionally known type and has three forward speeds and one reverse speed, and the required speed is obtained by appropriately operating the clutches 27, 28 and the play 1-30, 36. It is something that can be done. The overdrive planetary gear transmission mechanism 50 includes a direct coupling clutch 54
is engaged and the brake 56 is released, the shaft 14.26
1, the brake 56 is engaged,
When clutch 54 is released it engages shaft 14.26 in overdrive.

The automatic transmission AT described above includes a hydraulic control circuit CK as shown in FIG. This hydraulic control circuit CK
has an oil pump 100 driven by an engine output shaft 1, and hydraulic oil discharged from this oil pump lOO into a pressure line 101 has its pressure adjusted by a pressure regulating valve 102 and is guided to a select valve 103. The select valve 103 has shift positions of 1.2, D, N, R, and P, and when the select valve 103 is in the 1.2 and D positions, the pressure line 101 is connected to the boat a of the select valve 103.
, b, and c. Port a is fully connected to the actuator 104 for operating the rear clutch 28, and the valve 103
When the rear clutch 28 is in the above-described position, the rear clutch 28 is held engaged.

Bow) a is also connected near the right end of the 1-2 shift valve 110, pushing its spool to the right in the figure. Boat a further receives 1 via the first line L1.
A third line L3 is connected to the right end of the -2 shift valve 110 via the second line T12 and to the right end of the 2-3 shift valve 120.
are respectively connected to the right end of the 3-4 shift valve 130 via the 3-4 shift valve 130.

The first, second and third lines LL, L2 and L
3, first, second and third drain lines DL1, DI2 and DL 34p are branched off, respectively.
These drain lines DLI, DI2, and DI3 are provided with first, second, and third solenoid valves SL1, SL2, and SL3 that open and close the drain lines DLI, DL2, and DI3.
is connected. The above solenoid valves SLL, SL2,
When SL3 is excited with line 101 and boat a communicating, each drain line DLL, DI2, DI
3, resulting in 1st. The pressure in the second and third lines is increased.

Boat b is also connected to second lock valve 105 via line 140, and this pressure acts to push the spool of second lock valve 105 downward in the figure. When the spool of the second lock valve 105 is in the downward position, the lines 140 and 141 communicate with each other, and hydraulic pressure is introduced into the engagement side pressure chamber of the actuator 108 of the front brake 30 to hold the front brake 30 in the operating direction. . Boat C is connected to second lock valve 105, and this pressure acts to push the spool of second lock valve 105 upward. Additionally, boat C is connected to a 2-3 shift valve 120 via pressure line 106. this line 1
06 is the solenoid valve SL of the second drain line D'L2
2 is energized and the pressure within the second line L2 is increased;
When the spool of the 2-3 shift valve 120 is moved to the left by this pressure, it communicates with the line 107. Line 107 connects the actuator 108 of the front brake 30
When hydraulic pressure is introduced into the pressure chamber, the actuator 108 operates the brake 30 in the release direction against the pressure in the engagement pressure chamber. The pressure in the line 107 is also conducted to the 7-cut unit 109 of the front clutch 27, causing this clutch 27 to engage.

The select valve 103 is connected to the pressure line 101 in the ■ position.
has a boat d leading to the line 11.
2 to reach the l-2 shift valve 110, and then line 1
13 to the actuator 114 of the rear brake 36. 1-2 shift valve 110 and ? -3 SIBUT valves 120 are operated by solenoid valves SLI and S by a predetermined signal.
When L2 is energized, the spool is moved to switch lines, thereby operating a predetermined brake or clutch, and performing a 1-2, 2-3 speed change operation, respectively. The oil pressure control circuit CK also includes a car 2 pump valve 115 that stabilizes the oil pressure from the pressure regulating valve 102, a vacuum throttle valve 116 that changes the line pressure from the pressure regulating valve 102 according to the magnitude of the intake negative pressure, and this throttle valve. 1
A throttle backup valve 117 is provided to assist the throttle valve 16.

Further, the hydraulic control circuit GK of this example is provided with a 3-4 shift valve 130 and an actuator 132 to control the clutch 54 and brake 56 of the overdrive planetary gear transmission mechanism 5'O. The locking side pressure chamber of the actuator 132 is connected to the pressure line 101, and the pressure of the line 101 pushes the brake 56 in the engaging direction. In this 3-4 shift valve, as well as the 1-2. 101 and line 122 are cut off, and line 122 is drained. As a result, the hydraulic pressure acting on the release side pressure chamber of the 7-cut unit 132 of the brake 56 disappears, and the brake 56
7 actuator 134h of the clutch 54 in the engaging direction and release the clutch 54.

Further, the hydraulic control circuit CK of this example is provided with a lock-up control valve 133.
33 is the boat a of the select valve 103 via the line L4.
is communicated with. From this line L4 are drain lines DLL and DI.

2. Similar to DI3, a drain line DL4 is branched off, provided with a solenoid valve SL4. Lockup control valve 1
33, when the solenoid valve SL4 is energized and the drain line DL4 is closed, and the pressure in the line L4 increases, the spool cuts off the lines 123 and 124, and the line 124 is drained, causing the lock-up clutch 1 to close.
5 in the operating direction.

In the above configuration, the operational relationship between each gear, the clutch and brake, and the operational relationship between each gear and the clutch and brake are shown in Table 1, Table 1, Table 2, and Figure 3. An example of a control device for an automatic transmission AT according to the present invention, which controls a hydraulic control circuit GK associated with the transmission AT to perform speed change control and lock-up control, is an example of a control device for an automatic transmission AT in which the automatic transmission aAT is incorporated. Shown with engine EN.

In FIG. 3, a control unit 200 includes a lock-up control circuit 201 that performs lock-up control on automatic transmission AT, and a shift control circuit 2 that performs shift control.
02. In addition, automatic transmission A
The rotational speed of the output shaft 14 of the torque converter 10 of T and therefore the turbine rotational speed TSP is detected by the turbine rotational speed sensor TS attached thereto, and the engine EN (
7) Throttle opening TH of throttle valve 204 provided in intake passage 203 is detected by engine load sensor LS.

The turbine rotation speed signal St obtained from the turbine rotation speed sensor TS is output to the change state detection circuit 205, the lockup control circuit 201, and the speed change control circuit 202,
Further, a throttle opening signal Sn obtained from the engine load sensor LS is supplied to the lockup control circuit 201 and the speed change control circuit 202. Note that here, the turbine rotation speed TSP is treated as information corresponding to the vehicle speed, and the throttle opening TH is treated as information corresponding to the engine load.

In the embodiment, the change state detection circuit 205 detects whether the turbine rotation speed when the shift-up signal is output is on an upward trend or a downward trend, based on the turbine rotation speed signal St. In the example, the turbine rotation speed T
When the change rate of SP dTSP/dt>0, it is assumed that there is an upward trend, and when dTSP/d≦0, it is a downward trend.The signal Sp indicating whether the SP is on an upward or downward trend is as follows: The signal is output to the lockup control circuit 201.

The speed change control circuit 202 of the control 22) 200 receives the turbine rotation speed signal S from the turbine rotation speed sensor TS mentioned above.
t, the throttle opening signal Sn from the engine load sensor LS and the information obtained from the driving mode sensor (not shown) that detects the driving mode are determined in advance based on, for example, the turbine rotation speed-engine load characteristic shown in FIG. A calculation is made as to whether or not a shift should be made by comparing the shift up shift line and the downshift shift line of the shift map. Then, in accordance with this calculation result, the shift up signal Cp or the shift down signal Cp' is applied to the first, second and third solenoid valves SL1. SL2,
Output to SL3 and selectively excite them in the manner shown in Table 1 to shift the automatic transmission @AT gear to an upper gear (upshift) or a lower gear (downshift) It performs control and outputs a shift-up signal Cp or a shift-down signal Cp' to the lock-up control circuit 201.

In addition, the lock-up control circuit 20 of the control unit) 200
1, as in the case of the above-mentioned speed change control circuit 202, the turbine rotation speed S from the turbine rotation speed sensor TS
t, the information received by the throttle opening signal Sn and the driving mode signal from the engine load sensor LS is used to create a lockup of a shift map predetermined based on the turbine rotation speed-engine load characteristic as shown in FIG. 4, for example. ! ! Jl! A and the lock-up release line are compared to calculate whether lock-up or lock-up should be released. Then, depending on the result of this calculation, the lock-up activation signal C9 or the lock-up release signal Cq is activated.
' is output to the fourth solenoid valve SL4 of the hydraulic control circuit CK.

In this way, the shift amplifier performs downshifting based on the shift-up signal CP, the downshift is performed based on the shift-down signal Cp', the lock-up operation is performed based on the lock-up activation signal Cq, and the lock-up release signal 09 is activated based on the lock-up activation signal Cq.
The lock-up is released based on the lock-up operation, and the present invention is particularly characterized by the low and up-shift release timing when the gear is shifted up in the lock-up operating state, and this point will be described in detail below.

Now, in the state where the lock-up operation is being performed according to the lock-up operation line in Fig. 4, the turbine rotation speed TSP' with respect to the throttle opening TH' at that time is the fourth
When the shift-up shift line shown in the figure is exceeded, the shift-up signal Cp is immediately sent from the shift control circuit 202 to the first, second, and third solenoid valves ASLI, Sl, and 2 of the hydraulic control circuit CK. , is output to SL3.

At this time, if the change state detection circuit 205 outputs a signal to the lock-up control circuit 201 indicating that the engine speed Esp is on the rise (dTSP/dt > 0), as shown in FIG. A lock-up release signal Cq' for the fourth solenoid valve SL4 is output from the lock-up control circuit 201 at a time t2, which is delayed by a predetermined time from the time t1 at which the shift-up signal CP is output. And the above predetermined time (delay time)
is set as a length that corresponds to the rate of change in engine speed, that is, as a length that corresponds to the degree of engine revving. This effectively prevents the engine from revving up.

In addition, the engine speed Esp has a downward trend (dTSP
/dt≦0), the lock-up release signal Cq' becomes the shift-up signal C, as shown in FIG.
It is output (at time t) in synchronization with p. As a result, the lock-up is actually released earlier than the actual shift-up, and the engine speed Esp is reduced faster than when the lock-up is activated. Therefore, the difference in engine speed Esp before and after the upshift is reduced, and the shift shock is alleviated. In this case, since the engine speed is on a downward trend, the engine will not rev up even if the lockup is released faster than the upshift. An example of a driving situation in which the engine speed tends to decrease as described above is when the vehicle reaches a desired speed while accelerating, as experienced drivers often do. There may be cases where you intentionally release the accelerator pedal to actively shift up at a time that suits your will (such as intentionally reducing the throttle opening TH and performing the upshift operation shown in Figure 4). Operate the accelerator in a way that crosses the line).

Of course, in both cases when the engine speed is increasing or decreasing, the lock-up operating state is returned again at time t3.

The control unit 200 that performs the above-described control can be configured by, for example, a microcomputer, and the operating program of the microcomputer that configures the control unit 1-200 is, for example, as shown in FIGS.
The process is executed according to a flowchart as shown in FIG. This flowchart will be sequentially explained below. FIG. 5 shows an overall flowchart of the speed change control, and as can be seen from this figure, the speed change control is first performed from the initialization setting in step S1. This initialization setting initializes the ports and necessary counters of each control valve that switches the oil pressure control circuit of the automatic transmission, and sets the gear transmission mechanism 20 to 1st speed and the lock-up clutch 15 to release. do. After this, various working areas of the control unit 200 are initialized and the process is completed.

Next, in step S2, the position of the select valve 103, that is, the shift range is read. Then, in step S3, it is determined whether or not the read shift range is "l range". If the shift range is "l range", the lockup is released in step s4, and then in step s5. Calculate whether or not the engine will overrun by downshifting to 1st gear. When it is determined in step S6 that an overrun occurs, the shift valve is controlled to shift the gear transmission mechanism 20 to the second speed in step s7. If it is determined that there will be no overrun, the gear is shifted to the first speed in step S8 to prevent shift shock.

If the shift range is not "2 range" in step S3, it is determined in step S9 whether the shift range is "2 range". If the shift range is "2 range range", lock-up is disabled in step S10. Then, in step Stt, the gear is shifted to the second speed. On the other hand, if it is determined in step S9 that the shift range is not "? range'", this indicates that the shift range is in the D range after all, and in this case, the shift up control in step 512 and the step Shift down control at step 313 and lock up control at step 314 are performed in sequence.

As described above, steps S7, S8, sll, 31
When step S4 is completed, the process returns to step S2 and the above-described routine is repeated.

Next, the shift up control (step S in FIG. 5)
12) will be explained in detail with reference to FIG.

First, the gear position, that is, the position of the gear transmission mechanism 2° is read out. Next, based on this read gear position, it is determined in step S21 whether or not the vehicle is currently in the fourth gear. If it is not the fourth speed, the current throttle opening TH' is read in step S22, and data TSP of the shift up map corresponding to the throttle opening is read in step S23. An example of this shift map is shown in FIG. Next, in step 324, the current turbine rotation speed TSP' is read, and this current turbine rotation speed TSP' is compared with the data TSP of the shift-up map read above, and in step S25, the current turbine rotation speed TSP' is It is determined whether or not the turbine rotation speed TSPI is larger than the set turbine rotation speed TSPI shown in the shift line M f u in relation to the opening degree.

The current turbine rotation speed TSP' is the throttle opening TH
When the relationship is larger than the set turbine rotation speed TSPI, in step 326, flag 1 for one-stage upshift is read out, and this read flag 1 is read out.
It is determined whether is O or I, that is, whether it is in a reset state or a set state. Flag 1 is changed from 0 to 1 when a 1st gear upshift is executed. When flag 1, which stores the 1st gear upshift state, is in the reset state, after flag 1 is set to 1 in step S27. , a shift-up is performed in step 387, and the one-stage shift-up control is completed.

In step S26, if the determination as to whether flag 1 in the one-stage shift amplifier control system is 1 is 1, the control is completed as is.

Furthermore, even if the determination at the initial stage as to whether the vehicle is in the fourth gear is the fourth gear, the control is completed as is. Further, when it is determined in step S25 that the current turbine rotation speed TSρ' is not larger than the set turbine rotation speed TSP+ indicated by the shift line M f u in relation to the throttle opening TH, the current turbine rotation speed TSρ' is set to TSPI in step S29. For example, multiply by 0.8 to set a new set turbine rotation speed TSP2 on the new shift line Mfuz shown by the broken line in FIG. 6. Next, in step S30, the current turbine rotation speed T is set.
It is determined whether SP' is larger than the set turbine rotation speed TSP2 indicated by the speed change number Mfuz, and if TSP2 is larger than TSP', flag l is set in step 331. Reset and prepare for the next cycle, reverse T
If ``rspz'' is not larger than SP', the shift-down control is then performed.

Shift Down, No. 1' The shift down control (step 513 in FIG. 5) is
This is executed according to the downshift control subroutine shown in the figure. This downshift control is performed by first reading out the gear position, as in the case of upshift control. Next, based on the read gear position, it is determined in step 541 whether or not the vehicle is currently in the first gear. If it is not the first speed, the throttle opening degree TH is read out in step S42, and then 'step S4
At step 3, data TSPI of the shift down map corresponding to the read throttle opening TH is read. An example of this shift down map is shown in FIG. Next step 34
4, the current turbine rotation speed TSP' is read out, and this turbine rotation speed TSP' is set as the set turbine rotation speed TSPI which is the data of the shift down map read above.
In light of this, in the relationship between the current turbine rotation speed TSP' and the throttle opening TH, the downshift shift line Mfd,
It is determined in step S45 whether or not the turbine rotation speed is smaller than the set turbine rotation speed TSh shown in FIG.

When the current turbine rotation speed TSP' is smaller than the set turbine rotation speed TSP, flag 2 for one-stage downshift is read out in step 346. Flag 2 is changed from O to 1 when the gear is downshifted by one gear.

Next, it is determined whether this flag 2 is O or 1, that is, whether it is in a reset state or a set state. When flag 2 is in the reset state, flag 2 is set to 1 in step S47.
and downshifts by one step in step 348.
Completes 1st stage downshift control.

If it is determined in step 346 that the flag 2 is set, it means that downshifting is not possible, and the control is then completed.

Further, in step S45, if it is determined that the current turbine rotation speed TSP' is not smaller than the set turbine rotation speed TSP+ indicated by the first-stage downshift shift line Mfd, then the shift down is performed according to the current throttle opening. The map is read out, and in step S49, the set turbine rotation speed 'rspt indicated on the shift line Mfd of this map is set.
For example, by multiplying by 110.8, a new shift line Mf d! 6. Next, in step 550, if the current turbine rotation speed TSP' is smaller than the set turbine rotation speed "rspz" shown in the shift line M f d 2 in step 1, the new turbine rotation speed TSP2 is set. The control is completed, and if it is not smaller, flag 2 is reset to O in step S51, the control is completed, and then the lock-up control is started.

In addition, in the shift-up speed change control and shift-down speed change control explained above, when a speed change is not performed,
The reason for creating hysteresis by multiplying the map's shift line by 0.8 or 110.8 to create a new shift line is to create hysteresis when the engine speed and turbine speed are at the critical speed for shifting, and gear shifts are performed frequently. This is to prevent chattering from occurring due to

Lock-up control' Next, lock-up control will be explained with reference to FIG. 1O (step S14 in FIG. 5).

First, in the lock-up control, after reading the current throttle opening TH' in step 361, in step 562, a lock-up OFF map, that is, a shift line Moff ( From the map showing the set turbine rotation speed TSP corresponding to the throttle opening (see Figure 11)
, 0 Next, in step 563, the current turbine rotation speed TSP' is read, and in step 364, this read current turbine rotation speed TSP' is compared with the lock-up OFF map, and this current turbine rotation speed TSP' is read out.
It is determined whether SP' is larger than the set turbine rotation speed TSP indicated by the shift line MOFF. If the current turbine rotation speed TSP' is smaller than the set turbine rotation speed TSP, the lockup is released in step 365 and the process ends.

On the other hand, if the current turbine rotation speed TSP' is larger than the set turbine rotation speed TSP+, step 566
Then, from the lock-up ON map, that is, the map showing the shift line Man (see Figure 11) used for control to turn the lock-up into the ON (operating) state, another set turbine rotation corresponding to the throttle opening TH is determined. Number TSP2
is read out, and then in step S67 it is determined whether the current turbine rotation speed TSP' is larger than the set turbine rotation speed 'rspz. Then, T from TSP'
If SF3 is larger, lockup is activated in step 3.68 and the process ends, while TSP' is larger than TSP'.
If 2 is not larger, the process ends.

Adjustment of the output timing of the lock-up release signal when the shift-up signal is output during the low arp "1' lock-up operation of the shift arp I is performed by the subroutine shown in FIG.

First, in step 581, the contents of step 528 (see FIG. 6) are read. Next, in step 382, it is determined whether or not the content read in step 581 is an upshift, and if it is not an upshift, the control is terminated as is. On the other hand, if it is determined in step S82 that it is an upshift, a shift up signal Cp is output in step S83.

Thereafter, in step 584, it is determined whether or not the lock-up is activated. If it is determined that the lock-up is not activated, the control is immediately terminated. Also, in step S84, the lock key 1. If it is determined that the engine is in the operating state, step S85 is performed and the engine rotation speed Es
Whether p is on a downward trend or not, that is, dTSP/dt≦O
It is determined whether or not. This engine speed Esp
If there is a downward trend, that is, if dT SP/dt≦O, a lockup release signal Cq' is output at step 386. Further, if dTSP/dt≦O, that is, when the engine speed Esρ is on an upward trend, a time T proportional to the rate of change dTSP/dt of the turbine speed TSP, that is, the rate of change of the engine speed is set in step S87. Ru. And 1. In step 388, the process waits for the set time T to elapse, and after the elapse of the set time T, the process moves to step 386 and outputs the lockup release signal Cq'.

In this way, when the engine speed Esp is on a downward trend, the lock-up release signal Cq' is output in synchronization with the shift-up signal output, and the engine speed Esp is
When p tends to rise, the lock-up release signal Cq' is output with a delay from the shift-up signal by a time corresponding to the rate of change in the engine speed.

Although the embodiments have been described above, when the electronic control circuit 200 is configured by a microcomputer, it can be configured by either a digital type or an analog type. Also, to find out whether the engine speed is trending upward or downward, it is also possible to look at the acceleration obtained by further differentiating dTSP/dt.
In this case, it is possible to know earlier when the engine speed shifts to an upward trend or a downward trend, which is preferable in terms of improving responsiveness. Furthermore, the engine load can be detected by appropriate means such as intake pressure and the amount of depression of the accelerator pedal, and the engine rotation speed can be detected by the turbine rotation speed, the rotation speed of the engine output shaft itself, or the gear type transmission speed. It can be detected based on the output shaft rotation speed of the mechanism 20, etc.

(Effects of the Invention) As is clear from the above description, the present invention can reliably prevent the engine from revving up during upshifts and reliably alleviate the shift shock, resulting in an extremely improved shift feeling. You can get something excellent.

In addition, basically, control is performed to prevent the engine from speeding up and to alleviate gear change shocks depending on whether the engine speed is on an upward trend or a downward trend. Since it is possible to directly know whether or not a gear shift is to be performed, it is possible to obtain something favorable in terms of ensuring accuracy of control.

In particular, in the present invention, the delay time for outputting the lock-up release signal is set according to the rate of change in engine speed related to the degree of engine revving, so that engine revving can be effectively prevented. can.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of the present invention. FIG. 2 is a diagram showing a cross section of the mechanical part of the automatic transmission and its hydraulic circuit. FIG. 3 is an overall system diagram showing one embodiment of the present invention. FIG. 4 is a diagram showing an example of a speed change diagram. FIG. 5, FIG. 6, FIG. 8, FIG. 10, and FIG. 12 are flowcharts showing examples of control contents of the present invention. FIG. 7 is a diagram showing an example of a shift-up map. FIG. 9 is a diagram showing an example of a shift down map. FIG. 11 is a diagram showing an example of a lockup map. FIG. 13 is a diagram showing the relationship between the lock-up release timing, the engine speed, and the turbine speed when the engine speed is on an upward trend. FIG. 14 is a diagram showing the relationship between the lock-up release timing, the engine speed, and the turbine speed when the engine speed is on a downward trend. 1: Engine output shaft 10: Torque converter 14: Torque converter output shaft 15: Lock-up map 20: Multi-stage gear transmission mechanism 200: Control unit 201: Lock amplifier control circuit 202: Shift control circuit 205: Change state detection circuit EN: Engine SLI~SL4: Solenoid valve -ESP: Engine rotation speed TSP: Turbine rotation speed 7-r- and recovery group recovery Tsp (rp□) Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 1O Fig. 13 Sea door ZZ14 ! 33331.1 in 2Σda at S-jima 1f
21゜Tokito dpa (tl Fig. 14↑-↑3 Close: Ill (t)

Claims (1)

[Claims] (1) a torque converter connected to an engine output shaft; a gear-type transmission mechanism connected to the output shaft of the torque converter; a lockup mechanism that connects and connects the engine output shaft and the output shaft of the torque converter; A speed change electromagnetic means for controlling the supply of pressure fluid to the fluid type actuator that performs the speed change operation of the gear type transmission mechanism; and a lockup means for controlling the supply of pressure fluid to the fluid type actuator that performs the intermittent operation of the lockup mechanism. an electromagnetic means; a shift control means for outputting a shift up signal or a shift down signal to the shift electromagnetic means based on a predetermined shift characteristic; a lock-up control means for outputting a lock-up signal or a lock-up release signal to the lock-up electromagnetic means; a rotation speed change state detection means for detecting a state of change in the rotation speed of the engine output shaft; When a shift-up signal is output to the speed-changing electromagnetic means, if the rotation speed of the engine output shaft is on a downward trend based on a signal from the rotation speed change state detection means, the speed change is synchronized with the output of the shift-up signal. a lock-up release timing adjusting means for outputting a lock-up release signal with a predetermined time delay from the output of the shift-up signal when the rotational speed of the engine output shaft is on an upward trend; A control device for an automatic transmission, comprising: timer means for setting a time according to a rate of change in engine speed; and a control device for an automatic transmission.