JPH0658139B2 - Automatic transmission control device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a control device for an automatic transmission used with an engine equipped with an exhaust turbocharger mounted on an automobile or the like.

(Prior Art) Conventionally, acceleration is obtained according to the accelerator pedal depression speed, and in order to enable gear shifting with responsiveness that meets the driver's expectation, conversion is performed as the accelerator pedal depression speed increases. Set the vehicle speed to
As a result, when the accelerator pedal is suddenly depressed, some accelerations are accelerated (see Japanese Patent Application Laid-Open No. 57-195951).

By the way, in an engine equipped with an exhaust turbocharger, if a transient state called turbo lag occurs between the time when the accelerator pedal is depressed and the amount of exhaust gas increases and the rotational speed of the supercharger increases, the engine accelerates quickly. Therefore, it has been desired to develop a control device for an automatic transmission that can obtain good responsiveness even in this case.

(Object of the Invention) The present invention has been made based on the above technical background, and in an automatic transmission used with an engine equipped with an exhaust turbocharger, quick acceleration is achieved even when a turbo lag occurs. It is possible to provide a control device for an automatic transmission that is capable of always obtaining good responsiveness.

(Structure of the Invention) The present invention relates to a torque converter connected to an output shaft of an engine equipped with an exhaust turbocharger, a speed change gear mechanism arranged on an output side of the torque converter, and a speed change gear mechanism of the speed change gear mechanism. In an automatic transmission including a plurality of friction members for switching power transmission paths, a detecting unit for detecting a turbo lag generated during acceleration, and a turbo lag detection signal from the detecting unit are output to output a downshift signal to the friction member. And a control means.

According to the above configuration, when the detection signal is output from the turbo lag detection means and it is detected that turbo lag has occurred,
A downshift signal is output from the control means, the automatic transmission shifts down, and the output torque increases,
Rapid acceleration is performed according to the accelerator pedal depression state, and responsiveness that meets the driver's expectations can be obtained.

(Embodiment) FIG. 1 is a schematic view of an engine to which a control device for an automatic transmission according to the present invention is applied. In FIG. 1, 1 is an air cleaner, 2 is an intake passage, 3 is an intake branch pipe, 4 is an engine body, 5 is a torque converter 6 and a speed change gear mechanism 7.
And 8 is a control means, and 9 is an exhaust turbocharger. The control means 8 includes a throttle opening sensor 11 for detecting the opening Tθ of a throttle valve 10 provided in the intake passage 2 of the engine body 4 and a converter output shaft for detecting the output shaft speed NC of the torque converter 6. A rotation speed sensor 12, an engine output rotation speed sensor 13 that detects an output shaft rotation speed NE of the engine body 4, a fuel injection amount sensor 14 that detects a fuel injection amount TP of the engine body 4, and a surge tank in the intake passage 9 Pressure Pt
When the operating states of the automobile and the engine are detected in accordance with the detection signals respectively output from the surge tank pressure sensor 15 for detecting the shift, and the shift is required based on a predetermined shift shift pattern, the shift gear mechanism described above. The shift control is performed by outputting a shift-up signal or a shift-down signal to the friction member actuating means 16 for switching the power transmission path of No. 7.

Further, the throttle opening sensor 11, the engine output shaft speed sensor 13, and the fuel injection amount sensor 14 are used as detection means for detecting a turbo lag caused by an operation delay of the exhaust turbocharger 9. The operation of the turbo lag detecting means will be described based on the flowchart for turbo lag detection shown in FIG. First, the reset state "0" to the flag Fd for displaying whether the turbo lag has occurred (Step A _1). Next, the detection signals Tθ, NE, and TP of the sensors 11, 13, and 14 constituting the turbo lag detecting means are read (step A ₂ ). Then, based on the basic fuel injection amount map shown in FIG. 3, the basic fuel injection amount TPo to be injected in the steady state is obtained from the relationship between the throttle opening Tθ and the engine output speed NE (step A ₃ ).

Next, by the value (TPo × k) obtained by multiplying the basic fuel injection amount TPo by a constant k (0.5 to 1) for error absorption obtained by an experiment, and the value output from the fuel injection amount sensor 14. The calculated actual fuel injection amount TP is compared (step A ₄ ), and when it is determined that the actual fuel injection amount TP is smaller than the above value (TPo × k), the flag Fd is set. Set to "1" (step A
₅ ) It detects the occurrence of turbo lag.

The fuel injection amount sensor 14 is configured to detect the actual fuel injection amount TP based on the fuel injection pulse width normally obtained from the relationship between the intake air and the engine output shaft speed.

The control operation of the automatic transmission 5 configured as described above
Description will be given based on the flowchart shown in the figure. A flag F for first displaying whether the down-shifting control is executed to reset "0" (Step S _1).
The detection signals Tθ, NC from the throttle opening sensor 11 and the converter output shaft speed sensor 12 are read (step S ₂ ). Then, it is determined which gear range the values of the detection signals Tθ, NC are (steps S _{3 to} S ₅ ), and the gear stages of the transmission gear mechanism 7 are correspondingly changed to the first to fourth gears. Set to any of (steps S _{6 to} S
₉ ).

Then, based on the second FIG subroutine is executed for turbo lag detection (step S _10), the flag Fd is determined whether the set state "1" (step S _11). The flag Fd is in the set state, if the turbo lag it was confirmed that occurs, whether the flag F is in the set state, i.e. the shift-down control to determine whether already executed (step S ₁₂₎ . Then, the process returns directly to step S ₁₀ if it is determined that the shift-down control has already been performed in step S _12. Further, if it is determined that has not yet been down-shifting control is executed, and as well as executing the shift-down control, the flag F set state (step S _12, S _13), then the step S ₁₀
Then, the above flow is repeated.

Further, when the in step S ₁₁ the flag Fd not occurred turbo lag rather than a set state is confirmed, the flag F is determined whether the set state (step S _15), in step S ₁₃ Check whether the downshift control has been executed. When it is confirmed that the shift-down control has been executed, the shift-up control is executed to restore the gear stage of the transmission gear mechanism 7 to the original state (step S ₁₆ ), and the flag F is reset. after (step S _17), the step S ₂
Return to. Instead of the flag F is set state in step S _15, if it is confirmed that the shift-down control is not being executed, it is not necessary to return the speed change gear mechanism 7, as it is to the step S ₂ Return.

As described above, the turbo lag detecting means detects the occurrence of the turbo lag, and the control means 8 outputs the shift down signal to the friction member operating means 16 to execute the shift down control. It is possible to prevent poor acceleration and obtain good responsiveness.

The turbo lag can be detected by using the servo tank pressure detection sensor 15 instead of the fuel injection amount sensor 14. That is, as shown in FIG. 5, after the turbo lag display flag Fd is reset (step B ₁ ), the surge tank pressure sensor 1
5 and the detection signals Pt, Tθ and NE of the throttle opening sensor 11 and the engine output shaft speed sensor 13 are read (step B ₂ ). Then, based on the basic surge tank pressure map shown in FIG. 6, the surge tank pressure Pto in the steady state is obtained from the relationship between the throttle opening Tθ and the engine output shaft speed NE (step B ₃ ). This value P
It is determined whether or not the value (Pto × k) obtained by multiplying to by the error absorption constant k (0.5 to 1) is larger than the actual surge tank pressure Pt obtained from the detection value of the surge tank pressure sensor 15. (Step B ₄ ), Pt <(P
flag (Fd)
Is set (step B ₅ ).

(Effects of the Invention) As described above, in the present invention, in the automatic transmission used with the engine provided with the turbocharger, the turbo lag detecting means detects the turbo rub that occurs during acceleration such as when the accelerator pedal is depressed. Since the downshift signal is output from the control means at the time point, there is an effect that it is possible to prevent the acceleration failure due to the ragged lag and to always obtain a good responsiveness that meets the driver's expectation.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an engine equipped with a control device for an automatic transmission according to an embodiment of the present invention, FIG. 2 is a flowchart for turbo lag detection, and FIG. 3 is a map for reading a basic fuel injection amount, FIG. 4 is a flowchart showing the operation of the control device, FIG. 5 is a flowchart for detecting a turbo lag in another embodiment of the present invention, and FIG. 6 is a map for reading the basic surge tank pressure. 4 ... Engine body, 5 ... Automatic transmission, 6 ... Torque converter, 7 ... Shift gear mechanism, 8 ... Control means, 9
...... Exhaust turbocharger, 11 ...... Throttle opening sensor, 12 ...... Converter output shaft speed sensor, 14 ......
Fuel injection amount sensor, 15 ... Surge tank pressure sensor,
16 ... Friction member operating means.

Claims (1)

[Claims] 1. A torque converter connected to an output shaft of an engine having an exhaust turbocharger, a speed change gear mechanism arranged on an output side of the torque converter, and a power transmission path of the speed change gear mechanism. In an automatic transmission provided with a plurality of friction members for switching, a detection means for detecting a turbo lag generated during acceleration, and a control means for receiving a turbo lag detection signal from the detection means and outputting a downshift signal to the friction member. A control device for an automatic transmission characterized by being provided.