JPH0292748A - Engine control device in vehicle with automatic transmission - Google Patents

Abstract

PURPOSE:To enable a smoother speed change to be attained by decreasing an engine output after the predetermined time from outputting a speed change command signal and setting this predetermined time to an optimum value in accordance with a speed change condition. CONSTITUTION:A hydraulically operated multi-step speed change mechanism A, connected to an engine E, is controlled by a speed change control means B outputting a speed change command signal of shift up or down being based on the preset speed change characteristic. In this case, an output decrease means C, which decreases an output of the engine after the predetermined time from outputting the speed change command signal, is provided. While a change means D, changing the predetermined time by this output decrease means C in accordance with a speed change condition, is provided. The speed change condition contains various factors, related to a speed change shock, such as a speed change shift mutually different before and after a speed change and a throttle opening generating a change of the line pressure in a hydraulic circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine control device for a heavy vehicle equipped with an automatic transmission.

(Prior Art) Many automatic transmissions include a multi-stage transmission mechanism connected to an engine via a torque converter, and this multi-stage transmission mechanism is hydraulically operated in boat fishing. Then, by outputting a shift command signal, either a shift-up signal or a shift-down signal, to this multi-stage transmission mechanism, that is, a solenoid valve incorporated in its hydraulic circuit, based on preset shift characteristics, a multi-stage transmission mechanism is created. The speed change of the speed change mechanism is performed. .

When changing gears in such an automatic transmission, gear shifting is likely to occur, and for this reason, as shown in Japanese Patent Application Laid-Open No. 60-248445', engine output is reduced by retarding the ignition timing of the engine during gear shifting. It is proposed to lower the

(Problems to be Solved by the Invention) 1- As mentioned above, in a device that lowers the engine output during gear shifting, if the engine output is lowered immediately after the gear shift command signal is output, the engine output will decrease excessively. This effectively prevents shift shock, which is undesirable. For this reason, it has been considered to reduce the engine output after a predetermined period of time has elapsed since the output of the shift command signal, taking into consideration the delay in the operation of the multi-stage transmission mechanism, that is, the time required to switch the hydraulic circuit for shifting.

However, if 2 predetermined times are set as a certain constant value, the timing at which the enmoji output decreases will not necessarily be optimal, and some countermeasures are desired in this respect. More specifically, the time required to switch the hydraulic circuit of a multi-speed transmission mechanism depends on the speed change conditions,
For example, it changes depending on the gear shifting mode and the throttle opening during gear shifting. Therefore, even if the above-mentioned predetermined time is set to be optimal under a certain shifting condition, this predetermined time will change if the shifting conditions are different. It will not necessarily be optimal.

Therefore, an object of the present invention is to always optimally set this predetermined time to achieve smoother gear shifting, assuming that the engine output is reduced after a predetermined period of time has elapsed after the output of a shift command signal. To provide a control device for an engine with an automatic transmission, the present invention has the following features. The composition is as follows. That is, as shown in the block diagram in Figure 1:3, a hydraulically operated multi-stage transmission mechanism is connected to the engine, and the transmission speed is 11; 12 based on preset transmission characteristics.
Shift up signal or shift down 4 to multi-speed transmission mechanism
In an engine with an automatic transmission equipped with an 11-stage speed change control that outputs a 431-inch speed change command, 11; F-cho-dan.

and a changing means for adjusting the predetermined time according to the speed change conditions. .

The shift conditions include the mode of shift, that is, the difference in gear position after the shift, such as shifting from 1st gear to 2nd gear or shifting from 2nd gear to 3rd gear, and the change in line 1 of the oil bar circuit. This can include various factors related to the throttle/slot opening range and shift gears that cause this.

(Embodiment) In FIG. 1, the engine l is an in-line four-cylinder Otto type engine, and an automatic transmission 2 is connected to the engine l. The automatic transmission 2 is comprised of a torque converter 3 with a pull-up clutch and a gear-type multi-stage transmission mechanism 4 with four forward speeds.

The multi-stage transmission mechanism 4 is hydraulically operated, that is, the gears are changed by switching the operating states of a plurality of hydraulic actuators for switching power transmission paths. Shifting is performed by switching the operating states of a plurality of electromagnetic valves 6 to 8 provided in a hydraulic circuit 5 for the actuator. .

1- The switching control of the electromagnetic valves 6 to 8, that is, the speed change; Engine negative a::i is used as a parameter to determine whether or not to perform a gear shift based on the determined gear shift characteristics, and based on this determination result, a gear shift command signal, that is, a shift up signal or a shift down signal. 1
Output No. 3. As will be described later, the control unit II 1 controls the ignition timing retardation request signal 5 (S=1) at a predetermined timing after the output of the shift command transmission -J-. 9 to output for unit ``2''
, Furthermore, the control unit [JI is further set in advance using parameters such as medium speed and engine output:;i...! Based on the up characteristics, the solenoid valve 9
Lockup ON Shinshin or Lockup Live OV
F4. ”, the lock-up crank of the torque converter 3 is controlled on and off by outputting the signal.

The control unit U2 controls the ignition timing,
The igniter 11 outputs a predetermined ignition timing (li number IG) to the igniter 11, and - the igniter 11 interrupts the primary current of the ignition coil 1:3 connected to the variable valve 12 at the timing of the IG, thereby generating The high voltage secondary current
The signal is applied to a predetermined spark plug 15 via the distributor 14 to cause ignition. Then, during gear shifting, the control unit U2 retards the ignition timing as will be described later.

The control unit U2 includes each sensor or switch 21.
~25 is input, and control unit U1
The signal from the sensor 26 is input manually. Sensor 2
1 detects the engine speed. sensor 22
is for detecting the throttle opening. sensor 23
is for detecting engine cooling water temperature. switch 2
4 detects that the foot brake is activated, and is turned on during braking. Sensor 25 detects the intake air clearing, which corresponds substantially during the fuel injection pulse. The sensor 26 detects the turbine rotation speed. In addition, from control unit U2 to LJ
A throttle opening signal TVO is output with respect to l.

Next, the reduction in engine output during gear shifting will be explained. In this embodiment, this reduction in engine output is obtained by retarding the ignition timing.

First, the ignition timing is retarded during gear shifting on the premise that the first-order condition is satisfied. That is, the cooling water temperature 'rW is greater than the predetermined value TWO (72°C in the example), and the engine speed Ne is between the idle speed N0 and the maximum allowable speed N1 (the maximum allowable speed is (The condition regarding the number N1 may be omitted), and the throttle opening degree 1゛■0 is larger than the predetermined opening degree (2/8 opening degree when shifting down, and 378 opening degree when shifting up). Only at the time of upshifting, it is also a 1i71 prerequisite for retard execution that the P assumed engine speed after upshifting is greater than a predetermined value (corresponding to the idle speed in the embodiment).

The ignition timing is retarded only during a predetermined time T3, which will be described later, but even before T3 elapses, the following
When the first condition is met, the ignition timing is retarded. That is, when the brake pedal is depressed, when the throttle opening becomes zero, and when the fuel injection amount corresponding to the intake air becomes equal to or higher than the predetermined value, The retard angle is set to be small or medium. Fig. 5 shows the retard angle of the retard angle of 11 depending on the fuel injection 11#, I''P.
- is shown, and in the hatched area in FIG. 5, the retard angle will be reduced to a medium level even at T3 elapsed time 011.

In accordance with the following 1i11 proposition, the start timing of retarding the ignition timing will be explained separately for downshifting and upshifting.

■During a downshift Basically, the timing to start the retardation during a downshift is a first predetermined period of time ``1''S elapsed from the time when the control unit IJ1 outputs the downshift signal J to the solenoid valves 6 to 8. Later, when the turbine rotation speed NT becomes larger than the predetermined rotation speed NIG (in the embodiment, the turn rotation speed when the engine is idling).

Then, as a backup, 1-2 first predetermined time '1
゛When the second predetermined time TM set larger than S has elapsed, the retardation is performed even if the turbine rotation It has become.

The first and second predetermined times '1'S and 'I'M are mapped as shown in Fig. 2 according to the mode of downshifting.In this map, the throttle opening J The larger the summer, the larger the line J1; and the shorter the time required for power transmission switching in the multi-stage transmission mechanism 4. Therefore, the larger the throttle opening, the smaller both 'S' and '1゛M are set. -0Also, as the number of oil F actuators that are operated in conjunction with downshifting increases (or as the difference in gear ratios increases with gear shifting), ``S'' and ``I'' M become more popular. Specifically, it is made the largest when shifting from 4th gear to 1st gear, is smallest when shifting from 2nd gear to 1st gear, and from 3rd gear to 2nd gear, and is made the smallest when shifting from 4th gear to 2nd gear. When shifting from 3rd gear to 1st gear, the magnitude is intermediate.In addition, when shifting from 4th gear to 3rd gear, since the shift shock is originally the most severe, the ignition timing is not retarded.

The ignition timing is retarded by a predetermined time T3, or the maximum retardation '+tIGR is made smaller as the engine speed increases, as shown in FIG. (Sometimes, a large retardation can cause the exhaust gas temperature to become too high.) The retard angle j−,l is gradually increased toward this maximum retard angle:, > r att (
The time during this time is 1'I (0°2 seconds in the example), and then the maximum retardation +; t + until a predetermined time T2 (>TI)
a n (holding time is 0.5 seconds in the example),
After that, the retard angle id is gradually decreased until [predetermined time]゛koS (>T2) (this decreasing time is 0 in the embodiment)
．． 2 seconds). In this way, the total time from the start of retardation of ignition timing to +fi until retardation is no longer performed is T3, and this T3 is 0.2+0.
It becomes 0.9 seconds of 5+0.2.

FIG. 2 shows how the ignition timing retards at the time of downshifting from the start to the end. In this FIG. 2, the turbine rotational speed N
' is greater than the determined rotational speed NIG.

■At the time of upshifting The retardation start timing at upshifting basically means that the turbine rotational speed NT is equal to the turbine rotational speed N 'I' (a predetermined rotational speed 1 relative to I) when the shift command signal is output. ``When it is detected that the value obtained by adding r is detected. In other words, in automatic transmissions, it is common for the accelerator to be depressed even when changing gears, so -■1
．． The engine speed shows a tendency to decrease after reaching the limit, and this temporary increase in engine speed by 11 is caused by
Let's look at it in terms of l-shit for T. This prevents an excessive decrease in engine output due to retardation of ignition timing. I] The predetermined rotational speed 1)r is mapped in advance according to the throttle opening degree and the mode of upshifting, as shown in FIG. More specifically, the larger the throttle opening, the larger the DT, and even with the same throttle opening, shifting from 1st to 2nd gear is faster than shifting from 2nd to 3rd gear. ``D''' is noticeable. Furthermore, upshifts are performed one gear at a time.
Furthermore, when shifting from 3rd to 4th speed, the ignition timing is not retarded since the shift shock is originally small.

Due to some reason during upshift, the turbine rotation speed N
T turns for the above predetermined number of times, L for the number of rotations DT, and jI! As a backup, when a predetermined period of time has elapsed, the ignition timing is started to be retarded regardless of the presence or absence of the above DT rotation. The time TQ is large when shifting from 1st speed to 2nd speed (O.a seconds in the embodiment).

When shifting from 2nd speed to 3rd speed, it is small (in the example (),
2 seconds).

Here, the precondition for retarding the ignition timing during upshifting is when the imaginary engine rotation fi N e 1 after the shift is greater than the predetermined rotation speed N, as described above. This predetermined rotation speed No. is set as the idle rotation speed in the embodiment. Also, p.
The estimated engine speed Nc+ is.

In the embodiment, the change rate of the gear ratio due to gear shifting (the gear ratio after gear shifting is changed to 1j;
It is calculated by multiplying the value (divided by the gear ratio of 1).

Note that the manner in which the ignition timing is retarded and the retardation time are performed in the same manner as during downshifting.

The content of the control at the time of upshifting described above is shown in FIG. 6, and this FIG. 6 shows a case where the turbine rotational speed NT exceeds L by a predetermined rotational speed fi DT before the elapse of a predetermined time TQ. There is.

Next, the ignition timing retard control during gear shifting will be described in detail with reference to the flowcharts shown in FIGS. 8 to 12. Note that in the following explanation, P indicates a step.

FIG. 8 shows the control contents of the control unit tJJ, and as will be explained in detail later, 1) At 51, the timing to start retarding the ignition timing during downshifting is set; At P52, the timing to start retarding the ignition timing during upshifting is set.

FIG. 9 shows the contents of P51 in FIG. 8, up to when the control unit Ul outputs a retard request signal (S=1) to U2 in response to the output of downshifting. This shows the processing of

First, in 1]1, it is determined whether the flag FA is 1 or old. When this flag]:Δ is 1, it means that a downshift signal has already been output. When the determination of P1 is No, it is determined in P2 whether or not it is time to downshift based on the shift characteristics. If the judgment of [)2 is Y[:, S, [)
At step 3, the count value of the timer rΔ is reset to O, and a shift down command (+j>) is output.

Thereafter, at P4, data such as turbine rotational speed NT, throttle opening degree ``I''vO, and first and second predetermined times ``S, 1''M are read.

After this, in step (3) 5, it is determined whether the throttle opening T VO is larger than a predetermined value (2/8 opening). If Yt:S is determined by this determination, then in 1]6, the fluctuate A is set to 1, and then the process moves to P7.

1) In step 7, it is determined whether the count value of the timer TΔ has become more than a person for a first predetermined time '1'S. This I
) When Y[':S is determined in step 7, it is determined in step 8 whether the turbine rotational speed N T has become larger than the predetermined rotational speed N I G. When the determination in P8 is YES, it is time to retard the ignition timing, and at this time, in P9, the retardation request signal S is set to 1.
(see also FIG. 2), and also resets the flag FA to O. Then, at [)lO, after confirming that 50 m5ec has passed since the output of the retard request (No. 3 S), this S is reset to 0 at pH, and the process returns.

If the determination in [)7 or P8 above is No.

At PI3, it is determined whether or not the current time of the timer l-A has become longer than the second predetermined time TM.

If the determination of PI3 is YES, the process moves to ))9 above.

1) N in either 2, P5 or PI3
If it is O, it is returned as is. Also, +i
When Y r': S in the determination of P l in ii, 11i
1, 1) The processing from 7 onwards is performed.

FIG. 10 on the Kamegami side shows the contents of 1) 52 in FIG. 8, and the control unit [Jl to U2
The process up to outputting a retard angle request signal (s=+) is shown.

First, in step 1]61, it is determined whether the fract C is 1 or not. This flag [? When C is 1, it means that a shift up signal has already been output, and when the determination in P61 is NO.

1) In 62, should you shift up based on the shifting characteristics? -j It is determined whether or not it is time to move. This I)62
Yl by discrimination? , S, 1) At 6-3, the count value of timer '[C is reset to O, and a shift-up signal as a gear change command of 511 inches is output. After this, in [) 64, data manual power, that is, turbine rotational speed N'F, throttle opening '-rvo, predetermined time TQ, engine rotational speed Ne, l-d
The rotation speed D i- and the operating state of the brake switch 24 are read. After this, at PO2, the turbine rotational speed N'ro at the time of outputting the shift-up signal 1- and the r-imagined engine rotational speed (turbine rotational speed) after the shift.
N c + is calculated.

1] At P66 after 65, the throttle opening 'l゛V
It is determined whether O is larger than a predetermined opening eLJ (3/8 opening). With this [)66 determination, Y I S -
If so, it is determined in P67 whether or not the brake is operated. When the determination in step 1]67 is NO, it is determined at PO2 whether the imaginary rotational speed Ncl is larger than a predetermined rotational speed Ni1 (equivalent to the turbine rotational speed at idle). .

If the determination in step 1)68 is YES, the current turbine rotation INT is read in P70.

1) After 70 [ ] 71, the current turbine rotation speed NT is changed to the turbine rotation speed N at the time of outputting the shift up signal.
It is determined whether or not the value is greater than the sum of 'l' a and 1)]゛. In this determination of 1)71, Y I': S
When ! ] 72, the ignition timing retardation request signal S is set to 1, and the flag I-'C is reset to 0. And 50m S at P7:3
(? Wait until C elapses, 1) In 74, 1 S
is reset to 0.

Said! ] When the determination in step 71 is NO, 1) In step 75, the counter mark 1 of timer I'C reaches the predetermined time 'T'.
' It is determined whether or not it is larger than Q. This 1〕75
If the determination is YF, S, the process moves to 111-1]72, and if the determination in 1)75 is NO, the process returns directly.

0; 1) If YES in 61, 1) 62~
]) Transition to P 70 without passing through 69.

If the determination in 1) 66 is NO, the determination in 67 is YES, or the determination in 1) 68 is NO, the return is made as is (Ignition timing retard) l, ).

Directly above ↓ Figure 11 shows the control contents of the control unit tJ2,
This is performed by interrupt processing for each ignition timing, and the output time of the ignition timing retard request signal 5 (=1) is 50 msec.
c is set in consideration of this ignition timing cycle.

First, in [)21, it is determined whether fruct B is 1 or not. This flag l? When 11 is 1,
This means that the 1111 prerequisites for starting the ignition timing later are met. If the determination in l-'21 is No, then in P22, the data manual input, that is, the engine speed Ne, the throttle opening '1゛■0, the cooling water temperature TW, the operating state of the brake switch 25, and the fuel injection jj, 1-P (calculated according to intake air: 11), basic ignition timing (calculated based on, for example, engine c'1 load and engine speed), maximum retard: 1t I G II (see FIG. 4) is read. After this, in the determination of l]23 to P25, when the cooling water temperature TW is greater than the predetermined value 'WO (72°C), and the engine speed Ne is between the idle speed No and the maximum allowable speed N. When there is a retardation request from the control unit tJl at the rotation speed (S=1), P
At 26, the flag FB is set to 1, and
Timer "T'l'3 is reset to O.

After ()26, it is determined from P27 to P30 that the throttle opening -r v o is not 0, braking is not in progress, and the fuel injection 'd is less than the predetermined value f(Nc) (see Figure 5). l) 31.
In this step, the ignition timing retardation fitΔIG accompanying the gear shift is calculated as described below. After this, on P32,
The value obtained by subtracting the retard angle ΔIG from the basic ignition timing IGO is set as the final ignition timing 1().Of course, this final ignition timing!G is output to the igniter 11.

] 1; 1 Note 1'''23-1] If any of the determinations in 25 is N
When it is O, the conditions for executing the retardation of the ignition timing are not satisfied, so in this case, after ΔIG is set to 0 in 1) 34, the process moves to P 32. Also, 1) above
If any of the judgments from 27 to P 30 is YIES,
Since this is the time to medium or small the retardation of the ignition timing, the flag FB is reset to 0 in P33, ΔIG is set to 0 in P34, and then the process moves to P:32. Furthermore, +iij
+jL! l) If YES in the judgment of 2 l,
Proceed directly to 1) 27 without going through [) 22 to P 26.

FIG. 12 The flowchart in FIG. 12 corresponds to the process of P31 in FIG. 1I. First, at 1) 41, timer TI'3
It is determined whether the count value of is smaller than TI. When Y r': S is determined in P41, the process moves to I]42 in order to gradually increase the retard angle M toward the maximum retard angle: l: 1a n as time passes, and the After the retard angle: lHΔIG is calculated based on the formula, the process returns.

11; 1) When the determination in 41 is NO, it is determined in step 4-3 whether the count value of timer 1B is smaller than 1゛2 or a cup. With this I'43 determination, Y[
−.

When S, the retard angle fllΔl G is set to the maximum retard angle f+i: I G H in I) 44, and the process returns. .

IYi 1) If the judgment in 43 is NO, the delay angle is clear △l
There is a time when G is gradually reduced from the maximum retard angle: 11 I G R. At this time, it is shifted to 1) 45 and based on the formula shown here, △! After G is calculated, it is returned. This can be done by an appropriate method, such as forcibly changing the direction of closing.

(Effects of the Invention) As is clear from the above description, the present invention makes it possible to optimally set the start timing for reducing engine output during gear shifting, thereby achieving smooth gear shifting.

[Brief explanation of the drawing]

FIG. 1 is an overall system diagram showing one embodiment of the present invention. FIG. 2 is a time chart showing the control details of the present invention. Figures 3 to 5 are diagrams showing maps used for control of the present invention. Figure 6 shows the control details during upshift, and corresponds to Figure 2. Figure 7 is a small diagram of the map used for control during upshifts. 8 to 12 are flowcharts showing control examples of the present invention. FIG. 13 is a block diagram showing the configuration of the present invention. Engine automatic transmission Multi-stage transmission Hydraulic circuit Solenoid valve (for speed change) Igniter ignition coil I4: Distributor 15: Spark plug 26: Sensor (turbine rotation speed) [''1: Control unit (for speed change control)

Claims (1)

[Claims] (1) A hydraulically operated multi-stage transmission mechanism is connected to the engine, and a shift control means outputs a shift command signal such as a shift-up signal or a shift-down signal to the multi-stage transmission mechanism based on preset shift characteristics. An engine with an automatic transmission comprising: an output reducing means that reduces the output of the engine after a predetermined time has elapsed from the output of the shift command signal; and a changing means that changes the predetermined time according to shift conditions. An engine control device for a vehicle with an automatic transmission, characterized in that: