JPH0733862B2 - Control device for automatic transmission and engine output torque - Google Patents

Description

Detailed Description of the Invention

[Industrial applications]

 The present invention relates to a control device for an automatic transmission for a vehicle.

[Prior art]

Controlling the engine output torque according to the state of progress of gear shifting in order to mitigate the impact of gear shifting is disclosed in, for example, JP-A-58-77138.
No. 59-97350, No. 59-140952, etc. However, in this case, before the control based on the first shift is completed, when the need for the next shift arises, the control based on the first shift and the control based on the next shift must be properly processed before the shift is changed. The impact may increase or the time required to switch the engagement state of the friction engagement device may become long, which may reduce the durability of the friction material. In an ordinary automatic transmission, the processing when the second gear shift occurs immediately after the first gear shift occurs is described in, for example, Japanese Patent Laid-Open No. 58-30558, "A delay time is set and the delay gear is generated within this delay time." A technique for issuing a command to execute the last gear shift "has been proposed.

[Problems to be Solved by the Invention]

However, the automatic transmission that changes the engine output torque at the time of shifting has not been disclosed particularly effectively in such a case. An object of the present invention is, in an automatic transmission that changes the output torque of an engine during a gear shift, when the need for the next gear shift continues before the processing of the first gear shift has not yet been completed,
(EN) A friction engagement device and a control device for an automatic transmission, which are capable of accurately executing processing of control of engine output torque based on a first shift and control based on a next shift.

[Means for Solving the Problems]

The present invention has means for controlling a friction engagement device and means for controlling an engine output torque as shown in FIG. 1 for the purpose of engaging and disengaging the friction engagement device in order to achieve a gear shift. In the automatic transmission and the engine output torque control device configured to control and control the output torque of the engine in accordance with the progress state of the shift, the need for the first speed shift has arisen. And a means for setting a first delay time until the control of the friction engagement device for achieving the first gear shift is started when the necessity for the first gear shift has arisen. And means for detecting whether or not the need for the second gear shift has occurred within a period after the first delay time has elapsed until the series of controls executed for the first gear shift are completed, If there is a need for a second shift within this period, the second Means for setting a second delay time until the control of the friction engagement device for achieving the shift is started, and a friction engagement device for achieving the first shift after the elapse of the second delay time. The control of the friction engagement device to achieve the second gear shift, and the control of the engine output torque to continue the control based on the first gear shift. After the switching control instructing means and the progress state of the second gear shift have reached the state where the engine output torque should be controlled, the engine output torque control based on the first gear shift is performed to control the engine output torque based on the second gear shift. The above problem is solved by providing a second switching control instructing means for instructing to change the control of the engine output torque so as to give priority to the control.

[Operation and effect of the invention]

In this way, when the necessity for the first and second gear shifts continues, the control based on the second gear shift is performed after the appropriate change is made to the control based on the first gear shift. An increase or an excessive increase in the time required to switch the engagement state of the friction engagement device is avoided, and good control can be performed. That is, according to the present invention, the delay time T1 is set after the necessity of the first shift is generated and before the control of the friction engagement device based on the first shift is started, and this delay time T1 has elapsed. If the second shift is required later, the delay time T1 'is newly set, and the friction engagement device for achieving the first shift is controlled after the newly set delay time T1' has elapsed. To instruct control of the frictional engagement device to cancel and achieve the second speed change. In this case, regarding the control of the engine output torque, the control based on the first shift is continued for a while.
Eventually, the progress state of the second gear shift progresses to a state where the engine output torque should be controlled. At that time, therefore, the engine based on the second gear shift is controlled with respect to the engine output torque control based on the first gear shift. With respect to the control of the output torque, the control of the engine output torque is instructed to be changed so that the control of the engine output torque based on the second shift is prioritized.

【Example】

The present invention will be described with reference to the embodiments in the drawings. In FIG. 2, a fluid torque converter 14 and an overdrive device 1 are provided between the input shaft 10 and the output shaft 12 of the automatic transmission.
6, and an underdrive device 18 are provided coaxially.
The lockup clutch L / C is the fluid torque converter 4
Are provided in parallel with each other, and under predetermined operating conditions, engine power is transmitted to the overdrive device 16 via the lockup clutch L / C without passing through the fluid torque converter 14. The overdrive device 16 has one planetary gear set 20 and the underdrive device 18 has two planetary gear sets 22, 24. The clutches C0 to C2, the brakes B0 to B3, are connected and fixed between the rotating elements of the planetary gear devices 20, 22, and 24.
And one-way clutches F0 to F2. FIG. 3 shows the relationship between the shift speed and the engagement state of each friction engagement device. ○ and × indicate the engaged state and the released state respectively, △ indicates the engaged state only when the engine is driven, D is the drive range, 2 is the second range,
L means low range, R means reverse range, and O / D means overdrive or direct connection. Returning to FIG. 2, the hydraulic control circuit 30 has a plurality of solenoid valves 32, and these solenoid valves 32 engage a friction engagement device (including a lockup clutch L / C) other than a one-way clutch. And release is controlled. An ECT (electronically controlled transmission) computer 36 calculates a gear stage and a gear change timing from a vehicle speed V, an intake throttle opening degree θ, etc., and based on the calculated values, a solenoid valve.
Control 32. The EFI (electronically controlled fuel injection) computer 38 calculates the fuel injection amount and the ignition timing from the engine speed Ne, the intake air flow rate Q, etc., and controls the engine 40. FIG. 4 illustrates a shift diagram in the D range.
Each shift line is determined from the intake throttle opening θ and the vehicle speed V, and 1, 2, 3, and O / D are the first speed, the second speed, the third speed, and the fourth speed (overdrive or direct connection), respectively. Means that the direction of the arrow indicates the shift direction. The control principle of the embodiment will be described. First, each parameter T1, T2, T3 will be described. Consider a case where the time from the need for the first gear shift to the need for the second gear shift is sufficiently long. The necessity of gear shifting occurs, for example, when a point determined by operating conditions (intake throttle opening degree, vehicle speed) moves on the gear shifting line of the gear shifting diagram as shown in FIG. After a lapse of a predetermined time T1 from the necessity of the first gear shift, the control signal of the solenoid valve 32 in which the gear shift command is generated is switched. This starts hydraulic control of the friction engagement device. After the frictional engagement device that is in the engaged state after the shift is started to be engaged, the engine output torque is reduced at the timing when the inertia phase starts. The engine output torque is reduced by reducing the ignition timing advance amount, the fuel supply amount from the fuel injection valve, or the intake air amount. When the engagement of the frictional engagement device that is brought into the engaged state after the shift is completed, that is, when the inertia phase ends, the return of the engine output torque is started.
The engine output torque is gradually returned over the time T2, and the engine output torque returns to the original value after the time T2 from the start of the return. As a result, the shift impact immediately after the end of the inertia phase can be mitigated. Lockup clutch L / C
Is switched from ON to OFF at an appropriate time during the shift (hereinafter, L / C engagement state and release state are defined as ON and OFF.), But after time T3 has elapsed since the shift command was issued. It is turned back on. The times T1 ', T2', T3 'based on the second gear shift correspond to the times T1, T2, T3 based on the first gear shift, and these times are set by the timer. Here, when the need for the second gear shift occurs after the time T1 has elapsed from the time when the need for the first gear shift has occurred and before all the processing based on the first gear shift has finished. The control principle of is explained. (1) Cancel the time T3 based on the first shift. (2) Continue to monitor the engine speed Ne based on the first speed change, the output shaft speed No of the automatic transmission, and the intake throttle opening θ. Note that Ne and No are monitored to detect the inertia phase as described later, and θ is whether or not the operating state of the vehicle has changed between the control region and the non-control region of the engine output torque during the shift control. To be monitored. (3) First, the engine output torque control based on the second shift is performed.
The engine output torque control based on the first gear shift is ended at the time when the engine output torque control based on the second gear shift is started, prior to the engine output torque control based on the gear shift. FIG. 5 shows a change in each parameter when it is necessary to change the engine output torque by the second shift before the engine output torque control based on the first shift is completed. At time t21, the necessity for the upshift from the second speed to the third speed during the power-on period, that is, the first speed change occurs. At time t22 after the lapse of time T1 from time t21, the gear stage signal is switched from the second speed to the third speed. At time t23, the need for an upshift from the third speed to the fourth speed during the power-on period, that is, the second shift occurs. At time t24, the inertia phase based on the first gear shift starts, and the engine output torque is reduced. At time t25, the inertia phase based on the first gear shift ends and the engine output torque starts to return. At time t26 when a predetermined time T1 'has elapsed from time t23, the gear stage signal is switched to the fourth speed. At time t27, the inertia phase based on the second gear shift starts, and the engine output torque starts to decrease. Ie the first
The engine output torque control based on the second shift is executed with priority over the engine output torque control based on the shift. At time t28, the inertia phase based on the second gear shift ends, and the engine output torque gradually returns to the original value. At time t29 when time T2 'has passed from time t28, the engine output torque becomes the original value. At time t30 when time T3 'has elapsed from time t26, the lockup clutch L / C is turned on. FIG. 6 shows changes in each parameter when it becomes necessary to change the engine output torque by the second shift after the engine output torque control is completed based on the first shift. At time t41, the need for the upshift from the second speed to the third speed during the power-on period, that is, the first gear shift occurs. At time t42 when time T1 has elapsed from time t41, the gear stage signal is switched to the third speed. At time t43, the necessity of downshifting from the third speed to the second speed, that is, the second speed change occurs. When the second shift is a downshift, the lockup clutch L / C is turned off as soon as the second shift is necessary. At time t44, the inertia phase based on the first gear shift starts, so that the reduction of the engine output torque is started. At time t45, the inertia phase based on the first gear shift ends and the engine output torque starts to return. At time t46 when time T1 'has elapsed from time t43, the gear stage signal is switched to the second speed. At time t47 when time T2 has elapsed from time t45, the engine output torque becomes the original value. In this embodiment, the engine output torque control based on the first shift is completed before the engine output torque control based on the second shift is started.
There is no change in the engine output torque control based on the gear shift. The inertia phase based on the second gear shift starts, and at time t48, the engine output torque starts to decrease. The inertia phase based on the second gear shift ends, and the engine output torque starts to return at time t49. At time t50 when time T2 'has elapsed from time t49, the engine output torque becomes the original value. At time t51 when time T3 'has elapsed from time t46, the lockup clutch L / C is turned off. FIG. 7 is a flowchart of a shift control routine based on the first shift. In this case, the first shift is an upshift from the second speed to the third speed when the lockup clutch L / C is on (engaged state). Variable T is elapsed time Ta, t
Used to measure b, the variable I is the engine speed Ne
Used for monitoring of. First, determine the values of variables T and I (steps 50, 52),
Go to each step in relation to the value. If both T and I are 0, that is, in the state before the first shift control is started, it is determined whether or not the first shift is necessary (step 54), and if it is necessary. Only proceed to the following steps. Elapsed time Ta since the need for the first gear shift
Is compared with a predetermined value T1 (step 56), 1 is substituted for T if Ta <T1 (step 58), and if Ta ≧ T1,
After substituting 0 for T (step 60), the first shift command is generated (step 62), and the control signal of the solenoid valve 32 is switched. The engine speed Ne is compared with a predetermined value Ne1 (step 6
4) If Ne <Ne1, that is, if the inertia phase has started, proceed to step 68. The predetermined value Ne1 corresponds to the product of the output shaft rotation speed No of the automatic transmission and the gear ratio of the automatic transmission before the first gear change, and when the inertia phase starts, Ne <Ne1. The intake throttle opening θ is compared with a predetermined value θ1 (step 68), and when θ <θ1, that is, when the vehicle operating state is in the engine output torque non-control region, the lockup clutch
Only turn off L / C (step 70). When θ ≧ θ1, that is, when the vehicle operating state is in the engine output torque control region, the lockup clutch L / C is turned off and the engine output torque is reduced (step 72). The engine speed Ne is compared with a predetermined value Ne2 (step 7
4), if Ne ≧ Ne2, substitute 2 for I (step 76),
When Ne <Ne2, that is, when the inertia phase ends, the engine output torque is restored (step 78). Predetermined value
Ne2 is a value corresponding to the product of the output shaft rotation speed No of the automatic transmission and the gear ratio of the automatic transmission after the first gear shift, and Ne <Ne2 when the end of the inertia phase approaches. The engine output torque is restored slowly over a period of time T2. Elapsed time Tb from the time when the first shift command is issued and a predetermined value
Compare with T3 (step 80), if Tb ≦ T3, substitute 2 for T (step 82), and if Tb <T3, allow lock-up clutch L / C to be turned on (step 84). , I
0 is substituted for (step 86). 8 and 9 are flowcharts of the second shift control routine when the need for the second shift occurs before the end of the first shift control routine. However, here, an upshift from the third speed of the power-on engine to the fourth speed is considered as the second speed change. Steps 50b, 52b, 54b, 56b, 58b, 60
b, 64b, 66b, 68b, 70b, 72b, 74b, 76b, 78b, 80b, 82
b, 84b and 86b are steps 50, 52, 54, 56 and 5 in FIG.
8, 60, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 8
Since it corresponds to 4 and 86, the explanation is omitted. However, each parameter Ta ', T1', Ne1 ', Ne2', θ1 ', Tb', T
3 ', I'and T'are based on the second gear shift. When the necessity of the second gear shift occurs, it is judged whether or not it is after the generation of the first gear shift command (step 90), and if it is before the generation of the first gear shift command, the first gear shift is performed. Cancel all control parameters T1, T2, T3, etc. based on (step 92), second
The shift control routine of FIG. 7 is executed with the shift of 1 as the first shift (step 94). If the need for the second gear shift has occurred after the generation of the first gear shift command, the lockup clutch based on the first gear shift
Cancel the time T3 to execute the L / C on (Step 9
6), control parameters Ta ', T1', N based on the second shift
Control similar to the first gear shift is performed in relation to e1 'and the like. However, in step 100, the engine output torque control based on the first shift is canceled before the lockup clutch L / C is turned off and the engine output torque control based on the second shift is executed. That is, the engine output torque control based on the second shift is prioritized over the engine output torque control based on the first shift. Although the present invention has been described with reference to the embodiments, it will be apparent to those skilled in the art that the present invention is not limited to the embodiments and various modifications and variations can be made.

[Brief description of drawings]

FIG. 1 is a block diagram showing the gist of the present invention, FIG. 2 is a schematic diagram of the entire control system, FIG. 3 is a chart showing the operating state of the friction engagement device at each shift stage, and FIG. FIGS. 5 and 6 exemplify shift lines, FIGS. 5 and 6 show changes in respective parameters when the need for the second shift occurs, FIG. 7 is a flowchart of the first shift control routine, and FIG. FIG. 9 and FIG. 9 are flowcharts of the second shift control routine. 14 ... Fluid torque converter, 40 ... Engine.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-59-140952 (JP, A) JP-A-58-107822 (JP, A) JP-A-59-97350 (JP, A)

Claims (1)

[Claims] 1. A means for controlling a friction engagement device and a means for controlling an engine output torque are provided to achieve a gear shift.
In an automatic transmission and an engine output torque control device configured to control engagement / disengagement of a friction engagement device and also reduce / control the output torque of an engine in accordance with a progress state of a gear shift, A means for detecting the need for the first gear shift, and, when the need for the first gear shift has occurred, until the control of the friction engagement device for achieving the first gear shift is started. First
And a means for setting the delay time of the second delay time within the period until the series of controls executed for the first shift is completed after the first delay time has elapsed.
Means for detecting whether or not the need for the second gear shift has occurred, and if the second gear shift has occurred within this period, the second
Means for setting a second delay time until the control of the friction engagement device for achieving the gear shift is started, and friction engagement for achieving the first gear shift after the elapse of the second delay time. A control for canceling the control of the device, instructing control of the friction engagement device to achieve the second shift, and instructing control of the engine output torque to continue control based on the first shift. 1 switching control instructing means and the engine output torque based on the second shift from the control of the engine output torque based on the first shift after the progress of the second shift progresses to the state where the engine output torque should be controlled. An automatic transmission and an engine output torque control device, comprising: second switching control instructing means for instructing a change in the engine output torque control so as to give priority to the above control.