JPH03264748A - Engine torque controller - Google Patents

Abstract

PURPOSE:To improve fuel consumption while reducing a shock at speed change time by combining ignition timing control and fuel injection control with a speed change condition and also additionally providing throttle control in these combined controls when necessary. CONSTITUTION:In an automobile provided with an engine 1 and an automatic transmission 2, a throttle control means A for controlling a throttle controller provided in an intake pipe 2 and an ignition/fuel injection control means B for controlling ignition/fuel control of the engine are provided. Further a control start/nd detecting means D, which detects a signal for controlling a start/end of these control means, is provided, and a detection signal of the means D is input to a controller C. Ignition timing, fuel cut and a throttle are controlled in good timing, so that a speed change shock is reduced by each control means, by outputting a control signal to the ignition/fuel injection control means B of the engine 1 and the throttle control means A when the control start signal is input, by this controller C.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine torque control system for reducing shock during gear shifting and improving exhaust emissions and fuel efficiency in automobiles.

[Conventional technology]

In the conventional device, as described in Japanese Patent Application Laid-Open No. 1-151741, engine torque control during gear shifting is performed using only fuel cut control to reduce gear shift shock.

[Problem to be solved by the invention]

In the above-mentioned conventional technology, shock during gear shifting is reduced by engine torque control using only fuel cut control. However, fuel control alone has poor responsiveness and seems to be problematic in view of current exhaust and fuel efficiency regulations.

The purpose of the present invention is to reduce shift shock by improving the responsiveness of engine torque control by combining not only conventional fuel cut control but also three engine torque control means, including ignition timing control and throttle control. The goal is to control engine torque, which leads to improvements in exhaust emissions and fuel efficiency.

[Means to solve the problem]

In order to achieve the above object, control start means, control end means, throttle control means, and fuel control means are provided.

The engine torque during gear shifting is controlled by using an ignition timing control means and combining the above three engine torque control means.

[Effect]

Using a control start means and a control end means that control engine torque by feeding back a signal from the turbine rotation speed, ignition timing control means and fuel control are performed based on the signal from the control start means and a signal from the controller. The throttle control means starts to be controlled in a timely manner so as to reduce the shift shock.

At the same time, it also combines fuel control and throttle control, leading to improved exhaust emissions.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 shows a throttle controller provided in an intake pipe 3, a throttle control means for operating the throttle controller, and an ignition/fuel controller for controlling engine ignition and fuel in an automobile equipped with an engine 1 and an automatic transmission 2. Control means are shown.

Further, control start/end detection means is provided for detecting signals for controlling the start and end of the three engine torque control means.

The signal from the turbine rotation speed is fed back to the controller in Fig. 1 and is input as a signal for a control starting means that controls the engine torque.Based on the signal from the control starting means, the engine's ignition/fuel system and throttle control are controlled. A control signal is output to each control means. Based on the signals, each control means controls ignition timing, fuel cut, and throttle (air amount) in a well-timed manner to reduce shift shock.

FIG. 2 shows three types of engine torque control, ignition timing control, fuel injection control, and throttle control, for reducing the shift shock caused by the inertia of the l-speed drive torque and the second-speed drive torque during the 1-2 shift.

Shifting starts from the dotted line a by the 1-2 shift signal shown in FIG. 2, and torque fluctuation occurs due to the inertia of the 1-speed drive torque and the 2nd-speed drive torque, which causes a shift shock.

In order to reduce this shift shock, three engine torque control means, ignition timing control, fuel injection control, and throttle control, are combined and controlled to lower the engine torque during shift, reduce torque fluctuations, and reduce shock. reduced.

FIG. 3 shows differences in engine torque responsiveness depending on control parameters when the above three engine torque control means are combined. As you can see from this figure, ignition timing control has higher responsiveness than other fuel or throttle controls. That is, when the ignition timing control signal is input, control is immediately performed and the engine torque is reduced. However, if you look at the diagram of HC and No emission characteristics depending on the ignition timing shown in Figure 5,
If the ignition timing is delayed too much in order to reduce the engine torque, fuel efficiency will be extremely degraded, so there is a limit to the retardation of ignition timing control, and the ignition timing cannot be delayed unnecessarily.

Therefore, as shown in Figure 3, fuel injection control, which has the second highest responsiveness after ignition timing control, is performed in parallel with ignition timing control, thereby reducing engine torque while compensating for the deterioration in fuel efficiency caused by ignition retardation. , it is possible to suppress fluctuations in drive torque during gear shifting like a wave mb, and shift shock can be reduced.

The shift shock can be reduced by the two engine torque controls of ignition timing control and fuel injection control described above, but as can be seen from the HC and No emission characteristics depending on the air-fuel ratio shown in Fig. Reducing the engine torque by increasing the air-fuel ratio means operating on the lean side. However, if the air-fuel ratio is set too lean, combustion will become unstable and exhaust will deteriorate. Therefore, exhaust emissions can be improved by controlling the amount of air through throttle control.

By combining and controlling the above three engine torque control means, it has become possible to perform engine torque control that improves responsiveness of engine torque control, reduces shift shock, and improves exhaust emissions and fuel efficiency.

FIG. 6 shows a flowchart of specific control operations from the start to the end of engine torque control during gear shifting.

As can be seen from this figure, first, it is determined whether the gear is to be shifted based on the gear shift signal, and then, if the gear is to be shifted, a signal indicating the turbine rotational speed Nt is read from the control start/end detection means shown in FIG.

Next, when changing gears, use a shift up signal as shown in Figure 7.
Or, it is determined from the gear change signal whether it is a downshift signal. Based on the results, engine torque control is performed during upshifts and downshifts.

The operation of engine torque control during the first upshift will be described.

When it is determined that the shift signal is the shift up signal shown in FIG. 7(a), the turbine speed read earlier is compared with the control start turbine speed N1 shown in FIG. 7(a), and N, ≦N1.
If this is the case, set a flag for engine torque control during upshifts, and set a flag for engine torque control during upshifts, and adjust the settings for ignition timing, fuel injection, and throttle control.
Torque control of the two engine torque control means is started.

In other words, the start of control means that the turbine rotation speed N decreases by upshifting as shown in FIG. 7(a), so the control starts when the value becomes lower than a certain turbine rotation speed N1. It has become.

While controlling the engine torque, if the turbine rotation speed N1 decreases as shown in FIG. 7(a) and the rotation speed Nt becomes lower than the control end turbine rotation speed Nl', the flag is cleared.
End engine torque control. If N1≦Nl', engine torque control is repeated as shown in the flowchart of FIG.

During downshifting, the turbine rotation speed also increases as shown in Figure 7(b), so at the time of this change, a turbine rotation speed N2 at the start of control and a turbine rotation speed N2' at the end of control are provided and compared with the turbine rotation speed N. , when Nt≧N2, a flag for engine torque control during downshifting is set and control is started, and when the turbine rotational speed Nt≧N2', the flag during downshifting is cleared and control is ended.

FIG. 8 shows the control details from when the engine torque control flag is set until it is cleared.

In the flowchart shown in Figure 6, if the flag is set, the 8th
As shown in the figure, an ignition timing retard angle a° is outputted to perform ignition timing control, then a fuel cut signal is outputted to control fuel injection, and finally a throttle full open signal is outputted to perform throttle control. The above three engine torque controls are controlled until the flag is cleared.

Further, as shown in FIG. 7, the turbine rotation speed can be replaced with a gear ratio. The gear ratio is the value of turbine rotation speed/output shaft rotation speed.

FIG. 9 shows the output of the turbine rotation speed when the number of gears for rotation speed detection is 10 as shown in FIG. 9(a) and 100 as shown in FIG. 9(b). It is shown that the output accuracy of the turbine rotation speed can be improved by increasing the number of gears from 10 to 100.

FIG. 10 shows three types of engine torque control: ignition, fuel, and throttle control during gear shifting using the timer method.

As shown in the figure, if the shifting conditions change, such as between 1st and 2nd speeds and between 2nd and 3rd speeds, the output torque also changes.

For this purpose, it is necessary to change the timings of the three engine torque controls (ignition timing control, fuel injection control, and throttle control) using a timer method as shown in FIG. 10 according to the shift conditions.

In Fig. 10, the third
As can be seen from the difference in engine torque response due to the control parameters in the figure, if control is performed taking into account the responsiveness of ignition timing, fuel injection, and throttle control, the ignition timing will be delayed by tl from the shift signal point A as shown in the figure. , fuel injection tl
, the throttle control will be delayed by tl.

By changing the respective times of t17 and tl according to the shift conditions and changing the control timing, reliable engine torque control can be performed. However, the delay time is 1. ．． 1. ．． Considering responsiveness, there is a range of tl>t1'>tt at 1°, so control is performed by changing the time according to the shift conditions within that range.

Furthermore, the control times ta and t2 tz are also changed according to the shift conditions.

Next, the engine torque control system controls ignition timing and fuel injection when changing gears with little change in rotational speed.

Control is performed using any one of the three engine torque controls of throttle control. This is because at low rotation speeds, exhaust emissions are good and fuel efficiency is not a big problem. FIG. 11 shows a flowchart of engine torque control using only ignition timing control during gear shifting at low rotation speeds.

First, the engine speed Ne is read into the controller and compared with Neo. Here N eo ” 2000r
pm, engine rotation speed Ne is 200Orpm+
In the following cases, select ignition timing control and ignition timing retard b°
output, and engine torque is controlled solely by ignition timing.

In addition, in engine torque control, ignition timing control, fuel injection control, slot)-JL/
A device for controlling engine torque by providing a computer for each control will be described.

As shown in the figure, there is a main computer, and by inputting the engine speed Ne, turbine speed Nt, oil temperature To, gear change signal, and air flow meter signal, it is used as a computer for ignition control, fuel control, and throttle control. Output is sent. Based on the signals sent, control signals are sent from each control system computer to each drive circuit, controlling the ignition device, fuel injection valve, and throttle actuator, and controlling engine torque during gear shifting. In other words, the three engine torque control means can be independently controlled by the main computer and three computers provided for each control.

FIG. 13 shows a control flowchart of the fuel cut means for each cylinder in a four-cylinder engine under fuel injection control.

As can be seen from the diagram, first, the engine speed N8 is led. Furthermore, it is determined whether to shift, and if it is a shift, the engine rotation speed Ne at that time and the cylinder control engine rotation speed Ne1t
Compare with Ne2+ Ne8. For example, Ne5=400
Orpm, Ne! = 300 Orpm, Nes=
When set to 200Orpm, when the engine speed Ne is 400Orpm or more, 4 cylinders are cut and Ne
1> When Ne≧Nez, 3 cylinder cut, Ne2>
When Ne≧Ne3, two cylinders are cut, and when the engine speed is less than 200 Orpm, one cylinder is cut.This cylinder cut reduces the engine torque during gear shifting.

Cylinder cut continues to be controlled until the shift is completed, and when it is determined that the shift is complete, all cylinders are restored.

Control accuracy can be improved by adding to the fuel injection control the above-mentioned cylinder-by-cylinder fuel cut control and injection pulse width control that controls the pulse width when injecting fuel.

〔Effect of the invention〕

As explained above, the present invention makes it possible to reduce shock during a shift and improve fuel efficiency by combining ignition timing control and fuel injection control during a shift.

Furthermore, by adding throttle control to ignition timing and fuel injection control, exhaust emissions during gear shifting can be improved.

In addition, each of ignition timing, fuel injection, and throttle control,
By providing a computer and using a timer to change the timings of the three engine torque controls according to the gear shifting conditions during gear shifting, reliable engine torque control can be performed.

Furthermore, control accuracy can be improved by adding cylinder cut control and injection pulse width control to fuel injection control.

[Brief explanation of drawings]

Figure 1 is a diagram showing the configuration of engine torque control according to the present invention, Figure 2 is a diagram showing engine torque control for reducing shift shock using ignition, fuel, and throttle control, and Figure 3 is a diagram showing differences in engine torque response due to control parameters. Figures 4 and 5 are HC and No emission characteristic diagrams based on air-fuel ratio 9 and ignition timing, and Figures 6, 7, and 8 are diagrams showing the operation and content flowchart of engine torque control during gear shifting. , FIG. 9 is a diagram showing an improvement in the output accuracy of the turbine rotation speed detection means.
Figure 0 is a diagram showing the control timing according to the shift conditions.
FIG. 1 is a flowchart of ignition timing control, FIG. 12 is a circuit diagram of each engine torque control, and FIG. 13 is a flowchart of cylinder-specific fuel cut control of fuel injection control. l...engine, 2...automatic transmission, 3...intake pipe.

Claims (1)

[Claims] 1. Engine torque control in a vehicle equipped with an electronically controlled ignition and fuel injection device and an automatic transmission, characterized by combining ignition timing control and fuel injection control depending on shift conditions. Device. 2. The engine torque control device according to claim 1, wherein throttle control is added to ignition timing and fuel injection control.