JP3056587B2 - Transmission 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 a shift control device for an automatic transmission comprising a main transmission and an auxiliary transmission.

[0002]

2. Description of the Related Art Generally, an automatic transmission, for example, an automatic transmission for an automobile, includes a multi-stage transmission gear mechanism and a hydraulic friction element, and switches the operating state of the friction element, that is, engagement and disengagement, to perform multi-stage transmission. Shifting is performed by switching the power transmission path of the gear mechanism.

In recent automatic transmissions, the number of stages has been increased. For this reason, as shown in Japanese Patent Application Laid-Open No. 61-99745, the automatic transmission is constituted by a main transmission and an auxiliary transmission. An apparatus that switches or shifts the main transmission and the auxiliary transmission simultaneously or alternately is disclosed. Both the main transmission and the sub transmission can be constituted by a multi-stage transmission gear mechanism and a hydraulic friction element.

When the automatic transmission is composed of a main transmission and an auxiliary transmission, when the automatic transmission as a whole obtains a specific shift, for example, when shifting from the second speed to the third speed, the main transmission and the auxiliary transmission are used. May need to be shifted together. In such a simultaneous shift, a shift shock is more likely to become a problem than in a shift by only the main transmission or a shift by only the auxiliary transmission. Such a problem is particularly remarkable when the shift direction of the main transmission and the shift direction of the auxiliary transmission are opposite to each other (when one is upshifted and the other is downshifted).

[0005] For this reason, the above publication discloses that when the main transmission and the sub-transmission are simultaneously switched to perform a predetermined shift, the sub-transmission is shifted before the main transmission is completed.
It is also disclosed to prevent a shift shock. That is, since the shift shock becomes extremely large when the shift of the auxiliary transmission is completed after the shift of the main transmission, it is disclosed that the shift of the auxiliary transmission is completed before the shift of the main transmission is completed. I have.

Of course, it is ideal if the completion of the shift of the sub-transmission and the completion of the shift of the main transmission at the same time, but it is very difficult to obtain such an ideal state.
The setting is made such that the shift completion of the auxiliary transmission is performed earlier than the shift completion of the main transmission.

[0007]

In the case of shifting by simultaneous switching of the main transmission and the sub-transmission, the main transmission and the sub-transmission are set to have a predetermined relationship from the viewpoint of preventing a shift shock. It is conceivable to perform shift control while relating.

For this reason, the applicant of the present invention has determined that the gear ratio advance indicating the shift progress state of the subtransmission follows the target gear ratio advance set with the gear ratio advance of the main transmission as a parameter. -Developed a device to control the back. That is, by setting the target gear ratio advance in accordance with the gear ratio advance of the main transmission, it is possible to optimally control the shift of the sub-transmission while relating to the shift progress state of the main transmission. . In addition, the target gear ratio advance is set to 100% before the gear ratio advance of the main transmission becomes 100% (the shift is completed at 100%).
%, The shift completion of the sub-transmission can be made ahead of the shift completion of the main transmission.

However, in the case where the shift of the sub-transmission is completed before the shift of the main transmission is completed, a considerable amount of shift shock occurs when shifting only the main transmission after the shift of the sub-transmission is completed. In this regard, some measure is desired. This also poses a problem when the feedback control of the subtransmission is performed as described above.

That is, when the feedback control of the sub-transmission is performed, considering that the feedback control may not always be performed properly, the final value of the target gear ratio advance, that is, the speed of the sub-transmission is changed. Completion point 1
The gear ratio advance rate of the main transmission when it becomes 00% is 100%
It will not be possible to set it to the most recent value. More specifically, the gear ratio advance of the main transmission when the target gear ratio advance is set to 100% is, for example, 85 to 90%, which is a value with a considerable margin from the time when the shift of the main transmission is completed. Will have to be set as

[0011] Even when the target gear ratio advance is set as described above, after the shift of the sub-transmission is completed, the shift of only the main transmission must be performed at least not less. When the speed of the main transmission alone is changed, when the main transmission is upshifted, a shift shock occurs due to the release of the inertia of the rotating system, and the main transmission is downshifted. The rotation system
A shift shock resulting from the absorption of the shear will occur.

Accordingly, it is an object of the present invention to perform a shift as an entire automatic transmission by simultaneously switching the main transmission and the sub-transmission, and to complete the shift of the sub-transmission before the completion of the shift of the main transmission. It is an object of the present invention to provide a shift control device for an automatic transmission in which shift shock can be reduced as a whole when the shift is performed.

[0013]

In order to achieve the above object, the present invention has the following configuration. That is, as described in claim 1 of the claims,
A main transmission and a sub-transmission, wherein at least a specific shift is performed by shifting both the main transmission and the sub-transmission, and a shift completion of the sub-transmission is completed by a shift completion of the main transmission. In such an automatic transmission, the gear ratio advance of the sub-transmission is set to a target gear ratio advance in which the gear ratio advance of the main transmission is set as a parameter during the specific shift. Feedback control means for performing feedback correction on the basic control value for the auxiliary transmission, and the feedback control converges the gear ratio advance of the auxiliary transmission to the vicinity of the target gear ratio advance. A target gear ratio advance changing means for changing the gear ratio advance of the main transmission corresponding to the final value of the target gear ratio advance to a larger value; and a feedback control by the feedback control means. Learning control means for correcting the basic control value by learning control based on a feedback correction amount, and a control gain for reducing a control gain of the feedback control when the feedback correction amount becomes a predetermined value or less. Changing means for changing the target gear ratio advance when the control gain becomes smaller than or equal to a predetermined value.

After the shift of the sub-transmission, the engine is shifted after the shift of the sub-transmission when the main transmission is shifted up in order to prevent torque shock when only the shift of the main transmission is performed. When the main transmission is downshifted, the torque of the engine may be increased after the shift of the sub-transmission is completed.

[0015]

According to the first aspect of the present invention, basically, by performing feedback control, optimally controlling the shift of the sub-transmission while relating to the shift of the main transmission, the shift shock is reduced. It can be more effectively prevented.

Further, the shift completion time of the sub-transmission is gradually approaching the shift completion time of the main transmission while observing the state of the feedback control, and the main transmission after the shift of the sub-transmission is completed. It is possible to reduce the degree to which only the shift is performed, and to further reduce the shift shock.

Further, after confirming that the feedback control is performed well, that is, the control state in which the shift completion of the auxiliary transmission is not delayed from the shift completion of the main transmission. Since the target gear ratio advance is changed only after confirmation, a situation in which the shift completion of the auxiliary transmission is erroneously delayed from the shift completion of the main transmission due to the change of the target gear ratio advance may occur. It can be reliably prevented.

According to the second and third aspects of the present invention, it is possible to control the torque of the engine at the same time, and to further effectively prevent the shift shock.

The configuration as described in claim 4 is preferable for preventing shift shock when the shift directions of both transmissions, in which shift shock is a problem, are opposite. Preferred aspects of the invention and its advantages will be apparent from the description of the following examples.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the output of the engine 1 is transmitted to drive wheels via an automatic transmission AT including a torque converter 2, a main transmission 3, and an auxiliary transmission 4. . As shown in FIG. 2, the torque converter 2 is provided with a pump 20 connected to the engine output shaft 1a, a turbine 21 provided opposite to the pump 20, and provided between the pump 20 and the turbine 21. And a stator 22. This stator 22
Is configured to rotate on a fixed shaft 24 integrated with the case 5 of the automatic transmission AT via a one-way clutch 23. The one-way clutch 23 includes a stator 22
Are allowed to rotate in the same direction as the pump 20, and the rotation in the opposite direction is prohibited.

The turbine 21 has a torque converter 2
Output shaft 2a is coupled to the output shaft 2a and the pump 20.
Is provided between the lock-up clutch 25 and the lock-up clutch 25. The lock-up clutch 25 is connected to the torque converter 2
It is constantly urged in the clutch engagement direction (lock-up direction) by the hydraulic pressure of the hydraulic oil circulating inside, and at the same time, is held in the open state by the release hydraulic pressure supplied from the outside. The shaft 1a and the converter output shaft 2a are configured to be directly locked up.

The main transmission 3 will be described. The main transmission 3 includes a front planetary gear mechanism 3A and a rear planetary gear mechanism 3
B, and the front-stage planetary gear mechanism 3 </ b> A includes three gear elements of a sun gear 30, a pinion gear 31, a ring gear 32, and a planetary carrier 34. Rear stage planetary gear mechanism 3B, sun gear 35 and pinion gear 3
6 and a ring gear 37, and a planetary carrier 38. The carrier 34 and the sun gear 35 are connected, and the sun gear 30 and the carrier 3
8 and the carrier 38 is connected to the output shaft 3 a of the main transmission 3.

The converter output shaft 2a is supplied to a ring gear 32 via a first clutch K1 and is connected to a ring gear 37 via a second clutch K2. The main transmission 3 includes three brakes fixed to the case 5, that is, a first brake B1, a second brake B2, and a third brake B3. The brakes B1, B2, B3 and the clutch K1, which are friction fastening elements,
Forward 3 depending on the combination of K2
It is configured to be able to attain the first speed and the reverse speed, and in addition, one-way clutches OWC1 and OWC2 are also provided.

The sub-transmission 4 will be described. The sub-transmission 5 is constituted by a planetary gear mechanism comprising three gear elements of a sun gear 40, a pinion gear 41, a ring gear 42, and a planetary carrier 43. Ring gear 4
2 is connected to an input shaft 4a of the auxiliary transmission 4;
a is connected to the output shaft 3a of the main transmission 3 via a gear 44, and the carrier 43 is connected to the output shaft 4b of the subtransmission 4. The auxiliary transmission 4 includes a brake BO fixed to the case 5, and the sun gear 40 and the ring gear 42 are connected via the brake B0 and the clutch KO. A high speed stage (H) and a low speed stage (L) can be achieved by a combination of a brake BO, which is a frictional engagement element, and an engaged / released state of the clutch K0. In addition, a one-way clutch OWCO is also provided. ing.

The automatic transmission AT includes brakes B1, B
2, B3, B0 and the combination of the engaged and released states of the clutches K1, K2, KO, as shown in FIG.
In addition to the first reverse speed, five forward speeds can be achieved, and a circle in the figure indicates a fastening operation. Further, the five forward gears and the gears of the main transmission 3 and the auxiliary transmission 4 are described below.
The relationship with the gear ratio is, for example, as shown in FIG.

Next, the configuration of the hydraulic circuit of the automatic transmission AT will be described. As shown in FIGS. 5 and 6, the line pressure PL generated by an oil pump (not shown) is supplied from a line pressure oil passage 57 to a manual valve 50. The manual valve 50 is connected to a shift lever. The shift position can be switched between a neutral position (N), a parking position (P), a reverse position (R), and a drive position (D) by operating a shift lever, and the drain pressure and the R range corresponding to these positions. Pressures, D range pressures (the pressures of these range pressures are equal to the line pressure PL) are supplied to the corresponding ports.

The brakes B1, B2, B3, which are frictional engagement elements of the main transmission 3, and the hydraulic system of the clutches K1, K2 will be described. As shown in FIG. 5, three shift valves 51, 52, 53 are provided. And two pressure control valves 54 and 55 are provided, and each shift valve 51, 52,
At 53, four lands are formed on the spool, and the spool is biased leftward by a spring 58,
The oil chamber 56 at the left end is an ON / OFF type solenoid valve SOL
Line pressure PL is supplied via A, SOL B and SOL C,
When these solenoid valves are ON, the oil pressure in the oil chamber 56 is drained, and the shift valves 51, 52, and 53 are at the positions shown in the upper half of each. When these solenoid valves are OFF, the line pressure PL is supplied to the oil chamber 56, and the oil chamber 56 is at the position shown in the lower half.

The brake B1 has a D range pressure oil passage 6
From 0, shift valve 52, oil passage 61, shift valve 5
3. The D range pressure can be supplied via the oil passage 62. A shift valve 52, an oil passage 64, a shift valve 51, an oil passage 65,
The D range pressure can be supplied via the shift valve 53 and the oil passage 66. Further, the R range pressure can be supplied to the brake B2 from the R range pressure oil passage 68 via the shift valve 51, the oil passage 69, the shift valve 53, and the oil passage 66.
The brake B3 includes a shift valve 51, an oil passage 70, a pressure control valve 55, an oil passage 7 from a D range pressure oil passage 60.
1 can supply the D range pressure. A shift valve 52, a shift valve 52,
The line pressure PL can be supplied via the oil passage 72, the shift valve 53, the oil passage 73, the pressure control valve 54, and the oil passage 74. The clutch K2 has a D range pressure oil passage 60,
D range pressure can be supplied via the oil passage 75. However,
In the drawing, reference numerals 77 and 78 denote orifices, and mark x denotes a drain port.

Further, accumulators 63, 67, 76 for receiving a modulator pressure PM corresponding to the engine torque are connected to the oil passages 62, 66, 75, respectively.
In each of the pressure control valves 54 and 55, two lands are formed on the spool, and the spool is
The oil chamber 82 at the left end is connected to an output port 84 through an oil passage 85 having an orifice 83, and a red pressure (constant pressure) is linearly applied to the oil chamber 81 containing the spring 80. The control pressure PC regulated by the solenoid valve 86 is supplied through an oil passage 87. The control pressure PC causes the hydraulic pressure of the output port 84 (the brake B3 and the clutch K
(The hydraulic pressure supplied to one). However, the pressure control valves 54 and 55 supply the pressure-controlled hydraulic pressure to the output port 84 when the hydraulic pressure is supplied to the respective input ports, and the output port 84 when the hydraulic pressure of the respective input ports is drained. The hydraulic pressure is also drained.

The hydraulic system of the brake BO and the clutch KO, which are the frictional engagement elements of the subtransmission 4, will be described.
As shown in FIG. 6, the shift valves 51, 52, 5
Two shift valves 90 and 91 having substantially the same configuration as the shift valve 3 are provided. In each of the shift valves 90 and 91, the spool is urged leftward by a spring 92, the spring accommodating chamber is drained, and the leftmost oil ON / OFF in room 93
The line pressure PL can be supplied through the OFF type solenoid valves SOLD and SOLE.

The brake BO has a line pressure oil passage 57
, Shift valve 90, oil passage 94, shift valve 9
1. The line pressure PL can be supplied through the oil passage 95.
The line pressure PL can be supplied to the clutch KO from the line pressure oil passage 57 via a shift valve 90, an oil passage 97, a shift valve 91, an oil passage 98, and an oil passage 99. However, by setting the solenoid valve SOLD to 0N, the clutch K
O includes a shift valve 90, an oil passage 97, a shift valve 91, a linear solenoid valve 100 from the line pressure oil passage 57.
It is possible to supply the hydraulic pressure adjusted by the linear solenoid valve 100 through the oil passage 101 and the oil passage 99 in which the solenoid valves SOL D and E are turned ON.
The hydraulic pressure of the clutch KO can be drained through the oil passage 101. Incidentally, reference numerals 102, 103, 10
Reference numeral 4 denotes an orifice, a mark x denotes a drain port, and an accumulator 96 for receiving the modulator pressure PM is connected to the oil passage 95.

The range and gear position relating to the automatic transmission AT and the positions of the shift valves 51, 52, 53, 90 and 91, that is, ON / OFF of the solenoid valves SOL A to SOL E.
Solenoid pattern and friction fastening required (K1, K2,
The relationship with the fastening patterns (B1, B2, B3, KO, BO) is as shown in FIG. The shift speed of the main transmission 3 and ON / OFF of the solenoid valves SOL A to SOL C
F solenoid pattern and friction fastening elements (K1, K
2, B1, B2, and B3) are shown in FIG. 8, and the second gear (A), the second gear (B), and the third gear (A) in FIG. The reason why the clutch K1 is engaged in the neutral gear position (N) and the parking range (P) is to increase the response of switching to the travel range or the reverse range.

Control System Next, a control system for controlling the automatic transmission AT will be described. As shown in FIG. 9, a detection signal of a first sensor 110 for detecting a rotation speed of a turbine output shaft 2a and an output of a main transmission 3 are input to a control unit 120 for controlling the automatic transmission AT. A detection signal of the second sensor 111 detecting the rotation speed of the shaft 3a, and a third sensor 1 detecting the rotation speed of the output shaft 4b of the auxiliary transmission 4.
12, a shift signal corresponding to each range detected by a plurality of switches provided on the shift lever 113, and a throttle opening from a throttle opening sensor 114 for detecting an opening of a throttle valve of the engine 1. Signal TVO, vehicle speed signal SD from vehicle speed sensor 115, and other detection signals from a brake switch and the like are input. The first to third sensors 110 to 112 are, for example, electromagnetic pickup type sensors, and are illustrated in FIG.

A drive signal is output from the control unit 120 to the solenoid valves SOL A to SOL E, and the linear solenoid valves 86, 100, 1
A drive pulse signal is output to the pixel 16. However, the linear solenoid valve 116 is for adjusting the modulator pressure. Also, the control unit 120
After that, an ignition timing signal is output to an igniter 117 as torque adjusting means for adjusting the ignition timing of the engine 1.

The control unit 120 includes an A / D converter for A / D converting an input signal as necessary, a plurality of waveform shaping circuits, an input / output interface, a microcomputer, a plurality of drive circuits, and the like. In the ROM of the microcomputer, a control program for a shift control based on a general shift map, various input signals and a shift map using a vehicle speed and a throttle opening as parameters (however, a program corresponding to a range and a shift position) is stored. (Including the solenoid pattern) is input and stored in advance. However, it is assumed that the control program for the shift control includes a shift control described later.

Outline of Shift Control Next, the point of shift control will be described. In the embodiment, the shift between the second speed and the third speed is performed by simultaneously switching the main transmission 3 and the auxiliary transmission 4 together ( The speed change from the second speed to the third speed, which is the time of upshifting when shift shock becomes more problematic, is defined as a specific speed change, and the other speed changes are performed in a known manner. The shift control for the shift from the second speed to the third speed, which is the above-described specific shift, will be schematically described with reference to FIG.

At the time of shifting from the second speed to the third speed, first, the shifting of the main transmission 3 is started. At the time of shifting from the second speed to the third speed, the third brake B3 for the main transmission 3 is used. Is engaged, and the clutch KO of the auxiliary transmission 4 is released. In FIG. 10, after the shift command is issued, the engagement hydraulic pressure of the third brake B3 rises with a delay corresponding to the invalid stroke of (the piston of) the third brake B3 for the main transmission 3. The engagement hydraulic pressure for the third brake B3 is set, for example, in accordance with the throttle opening (see FIG. 15), and the feedforward control is performed from the start to the end of the shift.

When the actual gear ratio advance Gm of the main transmission 3 reaches a predetermined value Gmo (for example, 5%), the shift of the auxiliary transmission 4 is started. The shift of the auxiliary transmission 4 is performed for an initial predetermined time TS.
For o, check the engagement hydraulic pressure Pko of the clutch KO.
This is performed by performing forward control (see FIG. 16). By the initial feedforward control, the engagement hydraulic pressure of the clutch KO is reduced from P3 to P4,
This P4 is the initial value of the feedback control described later (final value of the feedback control).

When the feedforward control for the subtransmission 4 is completed, the engagement hydraulic pressure Pko of the clutch KO is set.
However, until the shift of the auxiliary transmission 4 is completed, basically
Is controlled. This feedback control is performed such that the actual gear ratio advance Gs of the subtransmission 4 becomes the target gear ratio advance Gst as a predetermined target value. As shown in FIG. 17, when the gear ratio advance degree of the main transmission 3 becomes Gm1 (for example, 90%) before it becomes 100%, as shown in FIG. 100%
(So that the speed change of the sub-transmission 4 is completed). The target gear ratio advance Gst shown in FIG.
The shift shock is set to be the least, and a plurality of shift shocks may be set according to the engine load such as the throttle opening.

The gear ratio advance is described as follows. First, the main transmission 3 will be described as an example. The rotation speed of the converter output shaft 2a, which is the input rotation speed of the main transmission 3, is Nmi, and the output shaft 3 which is the output rotation speed of the main transmission 3 is Nmi.
When Nmo the rotational speed of a, the actual gear ratio Gr of the main transmission 3 are as follows, Gr = Nmi / Nmo The gear ratio before the shift start (the gear ratio progress = 0%) Gr
s, the gear ratio at the end of the shift is Gre (gear ratio advance = 100
%), The current gear ratio advance Gm is as follows. Gm = (Grs−Gr) / (Grs−Gre) The gear ratio advance Gs of the subtransmission 4 is set in the same manner. In FIG. 10, the rotation speed of the input shaft 4a of the subtransmission 4 is Nsi, and the output shaft is The rotation speed of 4b is shown as Nso.

When it is deemed impossible by the above-described feedback control of the auxiliary transmission 4 to make it impossible for the completion of the shift of the auxiliary transmission 4 to be later than the completion of the shift of the main transmission 3. In other words, as will be described later, instead of the feed-back control, the sub-transmission 4 is subjected to the feed-forward control until the shift is completed, or when the sub-transmission 4 is determined to be impossible, The shift is forcibly terminated.

The shift control is performed in accordance with the following control. First, a basic control value P1 for feedforward control of the main transmission 3 shown in FIG.
P2 is corrected by learning control based on the time until the actual shift of the main transmission 3 ends, and the time until the shift of the main transmission 3 ends converges to a predetermined target time (Q51 in FIG. 14, which will be described later). To Q55).

Second, at the time of feedback control for the subtransmission 4, the basic control value Pko (G
m) by the feedback correction amount ΔPko shown in FIG. 18 (Q26, Q3 in FIG. 12).
0, Q31, Q33-Q35). And the basic control value P
Reference values (control gains) P5, P6 for setting ko (Gm)
Is corrected by the learning control, and the actual gear ratio advance Gs of the subtransmission 4 accurately follows the target gear ratio advance Gst (Q62 in FIG. 14).

Third, when the actual time until the shift of the main transmission 3 ends is greatly deviated from the predetermined target time, the learning control for the sub-transmission 4 described above is prohibited. This prevents undesirable shift control of the subtransmission 4 based on erroneous learning (Q5 in FIG. 14).
6 is NO).

Fourth, the feedback control correction amount △ Pko (actually, the integrated value の Gs of the deviation に な る Gs of the gear ratio advance which is the basis of the calculation of △ Pko) of the sub-transmission 4 exceeds the predetermined value. Becomes smaller, the control gains ΔP1 and ΔP2 of the feedback control are gradually reduced, and the convergence of the feedback control is improved (Q5 in FIG. 14).
7, Q58).

Fifth, when the control gains ΔP 1 and ΔP 2 become smaller than predetermined values, Gm 1 shown in FIG. 17 is gradually changed to approach 100%, and Is approaching the point at which the shift of the main transmission 3 ends,
Eventually, the main transmission 3 and the sub transmission 4 are substantially simultaneously shifted (Q59 and Q6 in FIG. 14).
0).

Sixth, the field of the auxiliary transmission 4 shown in FIG.
If the basic control values P5 and P6 for the feedback control exceed a predetermined upper limit value or lower limit value, it is not possible to cope with the control on the sub-transmission 4 alone, so that the transmission until the shift of the main transmission 3 is completed. The target time Tmt is corrected by the learning control (Q63 to Q66 in FIG. 14).

Seventh, when the sub-transmission 4 is subjected to feedforward control, its end value shown in FIG.
The initial value P4 of the feedback control is corrected by learning control based on whether or not the shift of the auxiliary transmission 4 has been started at the start of the feedback control, and is synchronized with the start of the feedback control. 4 is started. Eighth, when the shift of only the main transmission 3 is performed after the shift of the sub-transmission 4 is completed, the engine torque control for reducing the shift shock is performed (FIG. 2).
6).

Details of Shift Control (Excluding Learning Control and Torque Control) Next, the details of shift control will be described with reference to flowcharts shown in FIGS. In the following description, Q indicates a step. First, in Q1 of FIG. 11, the signal from each sensor, at least the throttle opening T
VO and vehicle speed are read. In Q2, it is determined whether or not a shift is to be performed based on the shift characteristics set with the throttle opening and the vehicle speed as parameters.

In Q3, it is determined whether or not the result of the determination in Q2 is a shift from the second speed to the third speed. If the determination in Q2 is NO, no shift or the second speed to the third speed is performed. This is the time when the shift is executed in a known normal mode other than the shift, and the process returns to Q1 because it is unrelated to the shift control in the present invention.

If the determination in Q3 is YES, the timer TO is started in Q4. Thereafter, in Q5, the map shown in FIG. 15 is checked, the basic control value PB3 for the main transmission 3 is read based on the timer value TO, and the basic control value PB3 is output in Q6. The basic control value PB3 is a voltage signal corresponding to the engagement hydraulic pressure of the third brake B3.

At Q7, the actual gear ratio advance Gm of the main transmission 3 is read (calculated). After this, Q8
, The actual gear ratio advance degree Gm is
Value Gmo that is the start time of the operation (see FIGS. 10 and 17)
It is determined whether or not it is greater than If the determination in Q8 is NO, it is not yet time to start shifting the subtransmission 4, so the process returns to Q5 and only the shifting of the main transmission 3 proceeds.

[0054] If YES in the determination of Q8 is the Q 9, the actual gear ratio progress Gm of the main transmission 3 is determined whether it is less than 100%. Initially, this Q9 discrimination
If YES , the process proceeds to Q10, where it is determined whether the actual gear ratio advance Gs of the subtransmission 4 is less than 100%.

Initially, the determination in Q10 is YES, and the flow shifts to Q21 in FIG. In Q21, the timer TS is set to 0
Is determined, and if the determination in Q21 is YES, the timer TS is started in Q22, the flag is reset to 0 in Q23, and the process proceeds to Q24. If NO in Q21, the flow shifts to Q24 without going through Q22 and Q23.

In Q24, the count value of the timer TS becomes
It is determined whether or not it is smaller than TSo, that is, whether or not it is within the period for performing the feedforward control of the subtransmission 4 as shown in FIG. Initially, the determination of Q24 is YES
And the process proceeds to Q25. In Q25, as shown in FIG. 16, the basic control value Pko for (the clutch KO of) the subtransmission 4 is set based on the count value of the timer TS. Then, in Q36, the basic control value P
ko is output.

When the determination in Q24 is NO, the feedback control of the subtransmission 4 is performed. At this time, first, at Q26, the actual gear ratio advance Gs of the subtransmission 4 is read (calculated). Thereafter, in Q27, it is determined whether or not the flag is 1. Q27
At the first time when the process has proceeded to, the flag is reset to 0 in Q23, and the determination in Q27 is NO. This Q27
If the determination in step (1) is NO, as will be described later, in Q28, the basic control value P4 shown in FIG. 16 (which is also the end value of the above-described feedforward control and the initial value of the feedback control described later) ) Is corrected by learning control,
After being adjusted, the process proceeds to Q29.

At Q29, it is determined whether or not the actual gear ratio advance Gs of the subtransmission 4 is less than 100%. Initially, the determination in Q29 is YES, and the process proceeds to Q30. In Q30, the target gear ratio advance Gst of the auxiliary transmission 4 with respect to the actual gear ratio advance Gm of the main transmission 3 is determined by comparing the map shown in FIG.

Next, in Q31, the actual gear ratio advance Gs of the auxiliary transmission 4 is subtracted from the target gear ratio advance Gst to calculate a gear ratio advance deviation ΔGs. After this,
In Q32, the integrated value of the deviation ΔGs up to the previous time ΔG
The current deviation を Gs is added to s, and the integrated value ｓGs is updated.

In Q33, the difference ΔGs calculated in Q31 is compared with the map shown in FIG. 18 to determine the feedback correction amount ΔPko. Thereafter, in Q34, the actual gear ratio advance Gm of the main transmission 3 is compared with the map shown in FIG. 19, and the basic control value Pko (Gm) for feedback control is determined. Subsequently, in Q35, the feedback control amount ΔPko is added to the basic control value Pko (Gm) to calculate the final control value Pko. Then, the control value Pko set in Q35 is Q
It is output at 36.

When the speed change of the subtransmission 4 progresses and the gear ratio advance Gs increases, the determination of Q29 eventually becomes NO. In this case, when the shift of the subtransmission 4 is completed,
In Q37, the timer TS is reset to 0, and in Q38
After the flag is reset to 0, the process returns to Q5.

If the determination in Q29 is NO,
The determination in Q10 is also NO, returning from Q10 to Q5, and the shift of the main transmission 3 proceeds. Main transmission 3
If the actual gear ratio advance Gm exceeds 100%, the determination of Q9 becomes NO, and the learning control in Q11 described later is performed, and then the process returns to Q1.

Details of Shift Control (Learning Control in Q28) Regarding learning control in Q28 shown in FIG.
This will be described with reference to FIG. First, in Q41, it is determined whether or not the actual gear ratio advance Gs of the subtransmission 4 is 0. This determination is made by checking whether or not the shift of the subtransmission 4 is actually started. It is for. When the determination in Q41 is YES, the shift of the sub-transmission 4 is actually started, which is the final value of the feed-forward control for the sub-transmission 4 (the initial value of the feedback control). Value) is too small, which means that the engagement hydraulic pressure of the clutch KO is too low. Therefore, at this time, in Q42, the actual gear ratio advance Gs is compared with the map shown in FIG. 23 to determine the correction value ΔP4a. Next, in Q43, the correction value ΔP4a is added to the previous basic control value P4 (see FIG. 16) to correct the basic control value P4.

If the determination in Q41 is NO, it means that the engagement hydraulic pressure for the clutch KO of the auxiliary transmission 4 is too high, and in this case, a predetermined constant value ΔP4b is subtracted from the basic control value P4 in Q45. And the basic control value P4
Is corrected. After Q43 and Q45, Q4
In step 4, the flag is set to 1, and the process returns to Q29 in FIG.

As described above, at the end of the feedforward control of the auxiliary transmission 4 (at the start of the feedback control),
Learning control is performed so that the actual gear ratio advance of the subtransmission 4 becomes just 0%, and a field for making the actual gear ratio advance Gs of the subtransmission 4 performed thereafter to be the target gear ratio advance Gst. The feedback control is performed well.

Details of Shift Control (Learning Control in Q11) The learning control shown in Q11 in FIG. 11 will be described with reference to FIG. First, in Q51, the timer value counted by the timer TO is set as the actual shift time Tm of the main transmission 3.

In Q52, the throttle opening TVO
The target time Tmt until the shift of the main transmission 3 ends is set by collating the map shown in FIG. Next, in Q53, the difference ΔTm is calculated by subtracting the actual shift time Tm from the target time Tmt. Q54
Then, based on the deviation ΔTm, the correction amount ΔPB3 is determined by collating with the map shown in FIG.

In Q55, the basic control value P1 shown in FIG.
The basic control values P1 and P2 are updated by adding the correction amount .DELTA.PB3 to each of P1 and P2 (FIG. 1).
5 map rewriting). In this manner, the time until the shift of the main transmission 3 is completed converges to the target time Tmt.
The basic control values P1 and P2 for feedforward control of the main transmission 3 are corrected by learning control.

After Q55, at Q56, the main transmission 3
The actual time Tm up to the end of the shift is determined by a predetermined target time T
mt (for example, ± 10 of Tmt)
%).

If the determination in Q56 is YES, in Q57, it is determined whether or not the absolute value of the integrated value Σ △ Gs calculated in Q32 is larger than a predetermined constant value a.
If the determination in Q57 is NO, it means that the feedback correction amount is small.
In FIG. 18, predetermined constant values .DELTA.P01, .DELTA.P02 are determined from the reference values .DELTA.P1 and .DELTA.P2 for determining the feedback correction amount shown in FIG.
, The reference values ΔP1 and ΔP2 are changed to smaller values. The process of Q58 is performed in the field shown in FIG.
This is equivalent to reducing the slope of the characteristic line for determining the feedback correction amount to reduce the control gain of the feedback control.

After Q58, in Q59, the reference value ΔP1 changed in Q58 is smaller than δ1, and
It is determined whether P2 is smaller than δ2.
1 and δ2 are each set to a predetermined constant value. Q5
At the end of the judgment of No. 9, it is judged whether or not the reference values for feedback correction, that is, the control gains .DELTA.P1 and .DELTA.P2 have become sufficiently small and the control state has become sufficiently converged on the target value Gst.

If the determination in Q59 is YES, in Q60, Gm1 shown in FIG. 17 is changed according to the formula shown in Q60, where i is an arbitrary integer of 2 or more. The processing in Q60 gradually reduces Gm1 to 100%
(The solid line in FIG. 17 is changed to a dashed line in FIG. 17). As a result, the control is shifted to such a control that the shift end of the main transmission 3 and the shift end of the auxiliary transmission 4 end at the same time. As a result, after the shift of the auxiliary transmission 4 is completed, the degree of shifting only the main transmission 3 decreases (the remaining gear ratio advance until the gear ratio advance Gm of the main transmission 3 becomes 100%). ), Shift shock is reduced.

That is, while the main transmission 3 and the auxiliary transmission 4 are both shifting (the target gear ratio advance Gs in FIG. 17).
While t is set), transmission and reception of torque between the two transmissions 3 and 4 effectively prevents the transmission shock. When the shift of the sub-transmission 4 is completed and the shift of only the main transmission 3 is performed, the torque transfer using the sub-transmission 4 cannot be used, and a slight shift shock occurs. By making Gm1 close to 100%, the speed change ratio of only the main transmission 3 is reduced, and shift shock is more effectively prevented.

If the determination in Q57 is YES, the feedback correction amount is large and the setting of the reference values P5 and P6 for the feedback control is not suitable, or the target time until the shifting of the main transmission 3 is completed. This is when it is considered that setting of Tmt is impossible. At this time, in Q61, Q3
Based on the integrated value Σ △ Gs at 2, the map shown in FIG. 22 is collated to set a correction amount △ Pdko. Then Q
At 62, the above-mentioned .DELTA.Pdko is added to the feedback control reference values P5 and P6 shown in FIG. 19, and the values of P5 and P6 are changed. Map rewrite).

In Q63, the reference value after the change in Q62, that is, the learning value P5 is changed to the predetermined upper guard value UL.
It is determined whether the learning value P6 is smaller than 1 and the learning value P6 is smaller than a predetermined upper guard value UL2. When the determination in Q63 is NO, when the values of P5 and P6 are out of the corresponding range by changing the values, that is, there is a limit when the gear ratio advance Gs of the subtransmission 4 is further slowed down. .
More specifically, as is apparent from FIG.
Increasing 6 increases the engagement oil pressure of the clutch KO to delay the disengagement of the clutch KO, but this delays the gear ratio advance Gs of the auxiliary transmission 4. At this time, in Q66, the target time Tmt shown in FIG.
The value is changed to a value obtained by subtracting TO (the map in FIG. 20 is rewritten so as to shorten the target time Tmt). After this, Q
At 67, the timer TO is reset to 0, and the process returns to Q1.

If YES in Q63, it is determined in Q64 whether P5 is larger than a predetermined lower guard value LL1 and P6 is larger than a predetermined lower guard value LL2. You. If the determination is NO, P5
, P6 is out of the corresponding range, that is, when the gear ratio advance Gs of the subtransmission 4 is limited to a higher speed. At this time, in Q65, the target time Tmt shown in FIG. 20 is changed to a value obtained by adding a predetermined fixed time ΔTO to the previous time Tmt (the target time Tmt).
, And the map is rewritten in FIG. 20). This Q
After 65, the flow shifts to Q67. YES in the determination of Q64
In the case of, the change of the target time Tmt is unnecessary, and
Without going through Q65 or Q66,
Move to.

If the determination in Q56 is NO, the actual time until the shift of the main transmission 3 ends is greatly shifted from the target time Tmt. At this time, no processing is performed in Q57 and below, and
Move to. As described above, when the determination in Q56 is NO, the shift control of the main transmission 3 is not necessarily performed well, so the learning control for the sub-transmission 4 is prohibited, and the sub-transmission caused by erroneous learning is prohibited. Unwanted shift control of the transmission 4 is prevented.

Details of Shift Control (Torque Control) FIG. 24 shows torque control performed after the shift of the auxiliary transmission is completed. In FIG. 24, the point in time t1 is the point in time when the shift of the main transmission 3 is actually started, and the point in time t2
Is the time when the shift of the auxiliary transmission is completed, and t3 is the time when the shift of the main transmission 3 is completed. After the shift of the auxiliary transmission 4 is completed, the engine 1
Is constant, the automatic transmission causes a torque change so as to increase the torque due to the release of the inertia of the rotating system caused by the shift-up progress of the main transmission 3 as shown by the broken line in FIG. This causes a shift shock. However, in the present invention, the inertia release is compensated as shown by the solid line in FIG. 24 by reducing the generated torque of the engine 1 from the completion of the shift of the auxiliary transmission 4 to the completion of the shift of the main transmission 3. As a result, a smooth torque change is achieved, and shift shock is prevented.

In the embodiment, the torque of the engine 1 is reduced by retarding the ignition timing of the engine 1. More specifically, the retard amount △ θ of the ignition timing is determined based on the remaining gear ratio advance △ Gm (see FIG. 25) of the main transmission 3 when the shift of the auxiliary transmission 4 is completed (see FIG. 27). Igniter 117 so that this △ θ is realized.
Output a retard signal.

The above-described torque control will be described with reference to a flowchart shown in FIG. 26. This flowchart is such that an interrupt is started when the shift of the sub-transmission 4 is completed. is there. First, in Q70, it is determined whether or not the flag 2 is 1. When the flag 2 is 1, it indicates that the torque control is being performed.

Flag 2 is initially 0, so
The determination at 70 is NO. At this time, after the flag 2 is set to 1 in Q71, 100 is set in Q72.
The remaining gear ratio advance Gm is calculated by subtracting the actual gear ratio advance Gm of the main transmission 3 from%. Next, in Q73, referring to the map shown in FIG.
An ignition timing retard amount △ θ corresponding to the remaining gear ratio advance △ Gm is determined. Thereafter, in Q74, a retard signal is output to the igniter 117 in order to realize △ θ.

After Q74, at Q75, the main transmission 3
It is determined whether the gear ratio advance Gm is smaller than 100%. If the main transmission 3 has not completed the shifting, Q75
Is YES , and in this case, after returning, the process returns to Q70 again. When returning to Q70 again, the flag 2
Is 1, so the determination of Q70 is YES.
At this time, the flow shifts to Q74 without going through Q71 to Q73. Accordingly, until the shift of the main transmission 3 is completed, △ θ
The ignition timing continues to be retarded by the minute.

When the speed change of the main transmission 3 is completed, the determination of Q75 becomes NO . At this time, the flag 2 is reset to 0 in Q76, and thereafter, the retard amount △ θ is reset to 0 in Q77, and the control ends.

In the above embodiment, the ignition timing is retarded to reduce the torque generated by the engine 1 because the main transmission 4 is upshifting, but the main transmission 3 is downshifting. In some cases (for example, during 3 → 2 shift), the torque generated by the engine 1 may be increased (for example, the ignition timing is advanced or the fuel supply amount is increased). Further, the ignition timing is retarded in a known manner at the time of shifting, but in this case, the ignition timing is basically retarded during the shifting, and further after the shifting of the sub-transmission 4 is completed, the ignition timing is adjusted. May be additionally performed.

[Brief description of the drawings]

FIG. 1 is an overall view showing a drive system of an automobile.

FIG. 2 is a detailed view showing a configuration of the automatic transmission shown in FIG.

FIG. 3 is a diagram showing a relationship between a gear position of the automatic transmission and an operation state of each friction element.

FIG. 4 is a diagram showing a relationship between a gear position of an automatic transmission, a gear position of a main transmission, a gear position of an auxiliary transmission, and a gear ratio.

FIG. 5 is a diagram showing an example of a hydraulic circuit for a main transmission.

FIG. 6 is a diagram showing an example of a hydraulic circuit for a subtransmission.

FIG. 7 is a diagram showing a relationship between a shift speed of the automatic transmission, an operation state of each friction element, and an operation state of a solenoid incorporated in a hydraulic circuit.

FIG. 8 is a diagram showing a relationship between a shift speed of a main transmission, an operation state of a friction element, and an operation state of a solenoid incorporated in a hydraulic circuit.

FIG. 9 is a diagram showing a control system of the automatic transmission.

FIG. 10 is a diagram schematically showing shift control when a main transmission and an auxiliary transmission are simultaneously switched.

FIG. 11 is a flowchart showing a control example of the present invention.
G.

FIG. 12 is a flowchart showing a control example of the present invention.
G.

FIG. 13 is a flowchart showing a control example of the present invention.
G.

FIG. 14 is a flowchart showing a control example of the present invention.
G.

FIG. 15 is a map used in a control example of the present invention.

FIG. 16 is a map used in a control example of the present invention.

FIG. 17 is a map used in a control example of the present invention.

FIG. 18 is a map used in a control example of the present invention.

FIG. 19 is a map used in a control example of the present invention.

FIG. 20 is a map used in a control example of the present invention.

FIG. 21 is a map used in a control example of the present invention.

FIG. 22 is a map used in a control example of the present invention.

FIG. 23 is a map used in a control example of the present invention.

FIG. 24 is a diagram schematically showing torque control after the shift of the auxiliary transmission is completed.

FIG. 25 is a diagram showing a remaining gear ratio advance of the main transmission.

FIG. 26 is a flowchart showing an example of torque control after the shift of the auxiliary transmission is completed.

FIG. 27 is a map used for the control example shown in FIG. 26;

[Explanation of symbols]

3: Main transmission 4: Sub transmission K0 to K2: Clutch (friction element) B1 to B3: Brake (friction element) 120: Control unit Gm: Gear ratio advance of main transmission ΔGm: Remaining gear ratio Advance Gs: Gear ratio advance of sub-transmission Gst: Target gear ratio advance of sub-transmission ΔPko: Feedback correction amount Pko (Gm): Basic control value for auxiliary transmission (for feedback control) Δθ: Ignition timing retard amount

Continuation of the front page (72) Inventor Daisaku Moriki 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Inside Mazda Corporation (56) References JP-A-3-229933 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F16H 59/00-61/24

Claims (4)

(57) [Claims] A main transmission and a sub-transmission, wherein at least a specific shift is performed by shifting both the main transmission and the sub-transmission, and a shift completion of the sub-transmission is performed by the main transmission; In the automatic transmission, which is performed prior to the completion of shifting of the transmission, the gear ratio advance of the sub-transmission is set as a parameter with the gear ratio advance of the main transmission during the specific shift. The basic control for the sub-transmission is set so that the target gear ratio advance is achieved.
Feedback control means for performing feedback correction on the control value ; and a final value of the target gear ratio advance when the gear ratio advance of the sub-transmission converges around the target gear ratio advance by the feedback control. Target gear ratio advance changing means for changing the gear ratio advance of the main transmission to a larger value corresponding to the above, and feedback correction by the feedback control means
The basic control value is corrected by learning control based on the amount.
Learning control means, and when the feedback correction amount falls below a predetermined value.
In addition, the control gain of the feedback control is reduced.
Control gain changing means , wherein the control gain is reduced to a predetermined value or less.
The shift control device for an automatic transmission , wherein the target gear ratio advance degree is changed when the shift is performed . 2. The main transmission according to claim 1 , wherein the specific shift is performed by shifting up the main transmission, and the shift of the sub-transmission is completed at the specific shift. to determine the amount of reducing the engine torque in accordance with the remaining gear ratio progress of, characterized in that it and a torque control unit for controlling the generated torque of the engine so that the torque reduction amount of the determined can be obtained Automatic shifting
Gear shift control device . 3. The main transmission according to claim 1 , wherein the specific shift is performed by downshifting the main transmission, and at the time of the specific shift, when the shift of the auxiliary transmission is completed. to determine the engine torque increase amount according to the remaining gear ratio progress of, characterized in that it and a torque control unit for controlling the generated torque of the engine so that the torque increase amount of the determined can be obtained Automatic shifting
Gear shift control device . 4. A any one of claims 1 to 3, wherein when a particular shift, the shift direction of the main transmission and the auxiliary transmission is opposite to each other, and wherein the Self
Transmission control device for dynamic transmission .