JPH01167434A - Controller for engine - Google Patents

Abstract

PURPOSE:To improve drivability by eliminating the variation of the driving power by setting the selecting timing of the control characteristic as the degree of the control of an engine adjusting means by a control means, in the operation state where the driving power of the engine is not influenced. CONSTITUTION:A control unit 18 receives each signal of the main and subaccelerator position sensors 19 and 19a, throttle sensor 22, and a mode switch 63, and in the low engine revolution range, etc. such as on start, said control unit 18 turns-OFF and electromagnetic clutch 50 and directly opening/closing- operates a throttle valve 6 by an accelerating pedal 5 through a mechanical control mechanism 61. When the mode switch 63 selects the mode of the traveling feeling control or autospeed control as the control characteristics, the electromagnetic clutch 50 is turned ON at the time point when the range is set at a P or N range or when the aimed throttle opening degree nearly coincides with the signal of the throttle sensor 22, and the selection to an electric control mechanism 60 is performed, by turning-ON the electromagnetic clutch 50. Thus, drivability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an engine control device, and more specifically,
The present invention relates to an engine control device that controls engine adjustment means based on an accelerator operation amount.

(Prior Art) As the above-mentioned type of engine control device, for example, the one shown in Japanese Patent Application Laid-Open No. 1983-1.38235 is known. According to such a device, it is possible to set, for example, the opening characteristic of the throttle valve to the accelerator depending on the engine operating state.

Furthermore, there has also been proposed a valve having a plurality of opening characteristics, which can be switched depending on the engine operating state. As an example of this device, the applicant disclosed in Japanese Patent Application Laid-Open No. 59-12742 that an electrical control device that electrically controls the opening of the throttle valve malfunctions, and the electrical control of the throttle valve becomes impossible. If the valve cannot be opened, the engine control device improves engine reliability by controlling the throttle valve using a mechanical control mechanism configured to guarantee the minimum opening of the throttle valve. is suggesting. This engine control device includes an accelerator opening sensor that outputs an accelerator opening signal according to the amount of depression of the accelerator pedal, an actuator that controls the throttle valve, and an accelerator opening sensor that inputs the output signal of the accelerator opening sensor. a throttle valve electrical control device comprising: a control circuit that outputs an electrical signal to the actuator so that the throttle opening degree corresponds to the amount of depression;
and a throttle valve mechanical control device that mechanically connects the accelerator pedal and the throttle valve so as to guarantee the minimum opening degree of the throttle valve.

(Problems to be Solved by the Invention) According to the conventional engine control device described above, even when the throttle valve electric control device fails, at least the minimum opening of the throttle valve can be controlled by the function of the throttle valve mechanical control device. I can guarantee it.

However, the control characteristics of the mechanical control device, which is the degree of control of the throttle valve opening relative to the amount of accelerator operation, are extremely small compared to those of the electrical control device.
While the engine is running, when the failure condition returns to normal and the control is switched from the mechanical control device to the electrical control device, the throttle valve suddenly opens wide, causing a sudden change in the driving force or torque generated by the engine. The problem arises. Such problems occur not only in the conventional example described above, but also in those that have multiple characteristics when electrically controlled and are switched depending on the operating state (Means for solving the problem) The present invention has the following problems: It has a plurality of control characteristics that are the engine output adjustment means that adjusts the engine output, an accelerator, and the degree of control of the engine adjustment means with respect to the accelerator operation amount, and one control characteristic is selected according to the driving conditions. In the engine control device, the engine control device includes a control means that determines the degree of control of the engine adjusting means based on the relationship between the control characteristic and the accelerator operation amount, and the control means determines the switching timing of the control characteristic depending on the driving force of the engine. This feature is characterized in that it is carried out in an operating state that does not affect the operation.

(Operations and Effects of the Invention) In the present invention, as described above, the control characteristics are switched at an operating state that does not affect the driving force of the engine, so that fluctuations in the driving force do not occur. This improves drivability. As mentioned above, this effect
This is particularly noticeable when control of the throttle opening degree is switched from a mechanical control device to an electrical control device.

(Embodiment) Hereinafter, an engine control device according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows the overall configuration of an engine control device according to an embodiment of the present invention. In this figure, reference numeral 1 indicates an engine, and reference numeral 5 indicates an accelerator pedal that is depressed in response to a request for engine output. Engine 1 has intake passage 2
The intake passage 2 has an air cleaner 3 at one end.
The other end opens to the atmosphere through the engine 1, and the other end opens to the engine 1.
Supplying intake air to the engine. The engine 1 also has an exhaust passage 4, which has one end connected to the engine 1.
The other end is open to the atmosphere, and the exhaust gas from the engine is discharged. A throttle valve 6 is provided in the intake passage 2 to adjust the amount of intake air. The opening degree of the throttle valve 6 is controlled by a throttle valve operating device 7, which will be described in detail later, by pressing the accelerator pedal 5.
It is done through.

A fuel injection valve 12 is provided downstream of the throttle valve 6 in the intake passage 2 to inject and supply fuel. The fuel injection valve 12 is communicated with a fuel tank 16 via a fuel supply path 15 through which a fuel pump 13 and a fuel filter 14 are interposed, and receives fuel from the fuel tank 16.

The throttle valve operating device 7 is connected to a control unit 18 composed of a microcomputer. The control unit 18 includes an accelerator pedal position sensor 19 which is an accelerator detection means for detecting the amount of depression of the accelerator pedal, that is, the amount of accelerator operation, and an accelerator pedal position sensor 19 that is arranged upstream of the throttle valve 6 in the intake passage 2 to detect the amount of intake air. An air flow meter 20 to detect, a throttle position sensor 22 to detect the opening of the throttle valve, and a water temperature sensor 2 to detect the temperature of engine cooling water.
3. An air-fuel ratio sensor (lean sensor) 24 is arranged in the exhaust passage 4 and connected to detect the air-fuel ratio. In the normal operating state, the control unit 18 receives the detection signals from the sensors 19 to 24, performs calculations based on the signals, and sends a control signal to the throttle valve operating device 7 for controlling the opening and closing operation of the throttle valve 6. Output to.

This control unit 18 also controls the fuel injection valve 12.

The control unit 18 further includes an igniter 26
is connected to input a signal 4 indicating the number of ignitions, that is, the engine rotation speed, and output an ignition timing signal set at a predetermined timing to the igniter 26. This control unit 18! tl,=,
A distributor 27 and a battery 28 are connected, and input signals indicating the actual ignition timing and battery voltage. A signal for ignition from the igniter 26 is transmitted to the spark plug 33 via the distributor 27.
The igniter 26 and the distributor 27 constitute ignition control means. .

Throttle Valve Actuation Device 7 Next, the throttle valve actuation device 7 will be explained with reference to FIG. FIG. 2 is a diagram schematically showing the throttle valve actuating device 7. As shown in FIG.

The throttle valve operating bag W7 has a base plate 40, and the throttle valve 6 is disposed on one side of the base plate 40.

On the opposite side of the base plate 40 from the throttle valve 6, there are first to third segments 4L 42 extending perpendicularly to the base plate 40.
．． 43 are provided. The first segment 41 is connected to the throttle valve 6 by a wire 44, and by moving away from the substrate 40, the first segment 41 is connected to the throttle valve 6 by a wire 44.
It operates in the direction of opening. The throttle valve 6 is provided with a spring 45 that biases it in the closing direction, and the first segment 41 is biased toward the substrate 40 by the spring 45. The second and third segments 42.43 are connected by springs 46.4
7 in the direction of the substrate 40.

The second segment 42 is connected to the accelerator pedal 5 via a wire 48 so that it can be moved away from the substrate 40 depending on the amount of operation of the accelerator pedal. Thus, this second segment 42
The amount of movement corresponds approximately one-to-one with the amount of operation of the accelerator pedal, and for this reason, the accelerator pedal position sensor 19 is provided in the second segment 42. Note that a backup accelerator pedal position sensor 19a is provided directly on the accelerator pedal 5.

The throttle valve actuating device 7 further includes a throttle motor 49 composed of, for example, a pulse motor. A rotating shaft of the throttle motor 49 is connected to a pulley 51 via a clutch 50. A wire 52 is wound around this pulley 51, and the end of this wire is connected to the third
It is connected to segment 43. When the throttle motor 49 rotates while the clutch 50 is in the engaged state, the third segment 43 moves in a direction toward and away from the base plate 40 .

The first segment 41 has an end portion opposite to the substrate 40;
A mechanical operation protrusion 53 extending toward the second segment 42 is provided, and an electrical operation protrusion 54 extending toward the third segment 43 is provided at a portion closer to the substrate 40 than the second segment 42 . On the other hand, in the middle English part of the second segment 42, the first
A protrusion 55 extending toward the segment 41 is provided at a distance α from the mechanical operation protrusion 53.

At a position of the third segment 43 that substantially corresponds to the electrically actuating protruding part 54, a protruding part 56 extending toward the first segment 41 is in contact with the side wall of the electrically actuating protruding part 54 on the substrate 40 side. It is set up so that Note that it is desirable that the pulley 51 be provided with a servo throttle position sensor 57.

In the above configuration, the control unit 18, the throttle motor 49, the pulley 51. By the wire 52, the third segment 43, the first segment 41, and the wire 44,
An electrical control mechanism 60 for the throttle valve 6 is configured, and a mechanical control mechanism 61 for the throttle valve 6 is configured by the wire 48, the second segment 42, the first segment 41, and the wire 44. That is, the throttle valve operating device 7
has an electrical control mechanism 60 and a mechanical control mechanism 61, the electrical control mechanism 60 is in charge of controlling the throttle valve 6 in the normal operating state, while the mechanical control mechanism 61 is, for example, It is in charge of controlling the throttle valve 6 in the event of an abnormality such as a failure of the electrical system.

Operation of the electrical control mechanism 60 This electrical control mechanism 60 is activated by the driver's accelerator operation (
The so-called "driving requirements" are improved to match the driver's feeling in the driving characteristics of the vehicle in the practical range, such as acceleration, constant-speed running, deceleration, following of other vehicles, and high-altitude running. The system is designed to perform driving feel control and auto speed control that automatically optimally controls the throttle and gears to maintain the target vehicle speed set by the driver.

Map for Driving Feel Control This driving feel control basically determines the optimal target throttle opening T, in order to obtain engine output according to the various conditions mentioned above. This is done by calculating a. This target throttle opening TVOT is based on basic required characteristics, such as gear status, mode switch status,
Basic throttle opening T v O according to accelerator release, etc.
It is obtained by correcting B based on other required characteristics, such as accelerator depression speed, vehicle speed, atmospheric pressure, cooling water temperature, etc. The control unit 18 controls the basic throttle opening T v OB.
For the calculation of Figure 3A, Figure 3B, Figure 3C, Figure 3D.
As shown in the figure, first to fourth maps having control characteristic lines for control during power mode, economy mode, hold mode, and during accelerator release are stored in advance. The control unit 18 is also connected to a mode switch 63 for selecting one of the power mode, economy mode, and normal mode, and receives a signal from the mode switch 63 indicating the current driving mode. The control unit 18 is further connected to a select switch 64 for selecting a gear such as 1st speed, 2nd gear, 3rd gear, neutral, parking, reverse, etc. A signal indicating that is being received. The control unit 18 further stores maps for accelerator depression speed correction and vehicle speed correction shown in FIGS. 4A and 4B, as well as maps for other corrections.

Auto Speed Control This auto speed control automatically controls the throttle and gears optimally to maintain the target vehicle speed set by the driver as described above.The above throttle control is the same as the above driving feeling control. The mechanism used in the above is used as is, and the shift control is performed by outputting a 4th speed prohibition signal to the electronic automatic transmission using the control unit 18.

Operation of Mechanical Control Mechanism 61 This mechanical control mechanism 61 is mainly used when the electrical control mechanism 60 breaks down, and controls the minimum opening of the throttle valve 6 to avoid danger. used to secure. This mechanical control mechanism 61 has the above-described distance α between the protrusion 53 of the first segment 41 and the protrusion 55 of the second segment 42 . For this reason,
After the accelerator pedal 5 is depressed to a certain extent and the second segment 42 moves by the distance α, the protrusion 55 comes into contact with the protrusion 53, and after this, the second segment 42 moves the first segment 41 away from the board 40. , and the throttle valve 6 is controlled according to the control characteristic line shown by the imaginary line in FIG.

In FIG. 5, a typical control characteristic line used in the electrical control mechanism 60 is shown by a solid line L1.

Control by the control unit 18 Control of the throttle valve operating device 7 by the control unit 18 will be explained with reference to FIGS. 6 and subsequent figures.

In this control, first, a main routine is performed according to the flowchart shown in FIG.

First, in this control, initialization, that is, software reset is performed in step S1, and then step S1 is performed.
At step 2, the latch 50 is turned off, the electrical control mechanism 60 is temporarily inactivated, and the mechanical control mechanism 61 is used to control the throttle. Next, in step S3, a battery check is performed.

This battery check shows that the voltage terminal B of the battery is 8V.
This is done by determining whether there are more than When the determination in step S3 is NO, the process is unstable and the process returns to the beginning of the control.

On the other hand, when the determination in step S3 is YES, it is determined in step S4 whether the engine rotation speed is greater than 50 rpm. When this determination is YES, it is a stable state, so it is determined whether the throttle valve may be electrically controlled. This determination begins with step S5, where it is determined whether the previous control was mechanical, that is, whether the flag S=1. When this determination is NO, that is, when the control at the time of the previous control was electrical, the control is performed with the same control characteristics as the previous time, and sudden torque fluctuations are not expected. Therefore, in step S6, the clutch 50 to put the electrical control system into operation.

On the other hand, when the determination in step S5 is YES,
This means that the previous control was performed mechanically, so switching from mechanical control to electrical control while driving will cause a sudden change in torque, so it is determined whether the conditions for switching are in place.

In this determination, first, it is determined whether the select switch 64 is set to the parking range P or the deep range N (step S7).

When this determination is YES, there is no change in torque even if the control characteristics are switched, so the process moves to step S6 and switches to electrical control. When the determination in step S7 is NO, it is further determined in step S8 whether the accelerator is fully closed. When this determination is YES, there is no fluctuation in torque, as described above, so the process moves to step S6 and switches to electrical control.

Even when the determination in step S8 is YES, there is no change in torque even if the control characteristics are switched, so the process moves to step S6 and switches to electrical control. After performing this switching, the flag S is set to 2 in step S9 to indicate that the control system is set to electrical control.
Set to .

After that, it is determined in step S10 whether the conditions for automatic speed control (ASC) are satisfied, and when this determination is YES, automatic speed control is performed (step 311), and NO.

In this case, for throttle control by the electric control mechanism 60, the target throttle opening T, is determined based on the maps shown in FIGS. 3A to 4B. .

is calculated (step 512). This throttle control will be explained in detail later.

If the determination in step S4 is No, the engine is unstable, and if the determination in step S8 is NO, the generated torque will fluctuate rapidly due to switching of control characteristics. Therefore, in step S13, the clutch 50 is the electrical control mechanism 60 is inactive, the throttle valve 6 is controlled by the mechanical control mechanism 61, and the flag S is set to 1. - After the above steps are completed, the clock output A for the watchdog timer is inverted in step S15, and it is set as the clock output A and output from the port (step 516), 1 cycle/? Terminate control.

Next, with reference to the flowchart of FIG. 7, the calculation of the basic throttle opening degree when calculating the target throttle opening degree in the throttle control in step S12 of the main routine will be described.

In this calculation, first, in step S1, it is determined whether the mode switch is 1, that is, whether the driving mode is the economy mode. When this determination is YES, it is determined in step S2 whether a flag AF indicating that the accelerator pedal is being returned is 1 or not. If this determination is NO, a map for economy mode driving shown in FIG. 3B is read out in step S3. On the other hand, if the determination in step S1 is NO, then in step S4 the mode switch is set to 3.
In other words, it is determined whether the driving mode is the power mode. When this determination is YES, it is determined in step S5 whether the flag AF is 1 or not. If this determination is NO, a map for power mode driving shown in FIG. 3A is read out in step S6.

On the other hand, when the determination in step S4 is No, it indicates that the mode switch is set to the normal mode, and in this case as well, the flag AF is
It is determined whether or not is 1 (step S7). If this determination is No, a map for normal mode driving shown in FIG. 3C is read out in step S8. Then, step S2, step S5, step S7
When the determination is YES, that is, when the accelerator is being released, a map for driving while the accelerator is being released, shown in FIG. 3D, is read out in step S9.

When reading the necessary map is finished, proceed to step 3.
10, the detected accelerator pedal depression amount α1 is shown on the control characteristic line of the map, and the basic throttle opening T
Find 1. Note that the basic throttle opening degree T1 is the basic throttle opening degree TVO! Corresponds to 1. When step SIO is completed, the basic throttle opening calculation routine is completed, and the above steps are repeated.

The calculated basic throttle opening degree is corrected by the accelerator depression speed, etc., and the target throttle opening degree TVOT in step S9 of FIG. 6 is calculated. □

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the overall configuration of an engine control device according to an embodiment of the present invention, FIG. 2 is a schematic diagram of a throttle valve actuation device used in the engine control device, FIG. 3A, FIG. 3B, Figures 3C and 3D are maps for calculating the basic throttle opening stored in the control unit, Figures 4A and 4B are maps showing correction coefficients, respectively, and Figure 5 is a map for calculating the basic throttle opening stored in the control unit. 16rgJ is a flowchart showing control of the throttle valve operating device in the control unit, and FIG. 7 is a flowchart for basic throttle opening calculation. 1... Engine 5... Accelerator pedal 6... Throttle valve 7... Throttle valve actuating device 18... Φ eye control unit 60... Electric control mechanism 61... Machine Control mechanism Fig. 3A Power mode Fig. 3B Economy mode VOB Fig. 3C Normal mode vo e Fig. 3D While releasing the accelerator Fig. 4A Accelerator depression speed correction Fig. 4B Vehicle speed correction v Fig. 5 Throttle

Claims (1)

[Claims] It has a plurality of control characteristics that are the engine output adjustment means that adjusts the engine output, an accelerator, and the degree of control of the engine adjustment means with respect to the accelerator operation amount, and one control characteristic is selected according to the driving conditions. In the engine control device, the engine control device includes a control means that determines the degree of control of the engine adjusting means based on the relationship between the control characteristic and the accelerator operation amount, and the control means determines the switching timing of the control characteristic depending on the driving force of the engine. An engine control device characterized in that the control is performed in an operating state that does not affect the engine.