JPH0833111B2 - Engine throttle valve controller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an engine throttle valve control device.

(Prior Art) Conventional throttle valve control device (Japanese Patent Laid-Open No. 62-168943
According to Japanese Patent Laid-Open Publication No. 2003-101242, the amount of change in the throttle valve opening with respect to the amount of depression of the accelerator pedal (also referred to as accelerator pedal opening) does not change, and the amount of change in the throttle valve opening with respect to that stroke is large at the beginning of depression of the accelerator pedal. The engine generated torque (engine torque) rises rapidly in the low rotation speed region when the accelerator pedal is depressed, and the longitudinal vibration applied to the vehicle during acceleration also increases.

Therefore, a device has been proposed in which a mechanism for changing the amount of change in the throttle valve opening with respect to the accelerator pedal opening is provided between the two mechanisms that rotate the accelerator pedal and the throttle valve.

This will be described with reference to FIG. 9. An accelerator pedal 1 swingably supported by a shaft 2 has a pedal portion 3 which receives a pedaling force of a driver at one end and a base of an accelerator wire 4 at the other end. The ends are joined.

The end of the accelerator wire 4 is connected to the outer peripheral end of the first drum 5 via a Nicostop 6. The first drum 5 has a shaft 7
Is rotatably supported by and is rotated at a constant ratio (R ₃ / R ₂ ) via the accelerator wire 4 as the accelerator pedal 1 is depressed.

On the other hand, the valve shaft 9 of the throttle valve 8 has a second drum 10
Is connected, and Nikostop is attached to the outer peripheral edge of the second drum 10.
The end of the throttle wire 12 is connected via 11 and the throttle valve 8 is opened as the base end of the throttle wire 12 is pulled, and the amount of air taken into the engine through the intake pipe 13 is increased. .

A nicostop 15 is connected to the base end of the throttle wire 12, and the nicostop 15 is slidably inserted into a guide groove 16 formed in the first drum 5. This guide groove
16 is formed along the radial direction of the first drum 5, and the rotation radius R ₄ of the Nicostop 15 changes as the Nicostop 15 slides in the guide groove 16.

A wire guide 25 is provided in the middle of the throttle wire 12, and the guide groove 16 is formed by curving in an arc shape around the guide 25 when the throttle valve 8 is in the fully closed state shown in the drawing. Even if it slides in the guide groove 16, the throttle wire 12 will not be pulled and the throttle valve will not open.

As a means for displacing the mounting position of the throttle wire 12 with respect to the first drum 5 in the radial direction of rotation,
A reciprocating rod 17 is connected to the reciprocating rod 15, and a motor 19 for reciprocating the reciprocating rod 17 against the return spring 20 via a link 18 is provided. The motor 19 is fixedly attached to the first drum 5.

The motor 19 is driven by a control signal sent from the control unit 21, and the control unit 21 inputs an engine speed signal, a water temperature signal, etc., and calculates a control signal according to the operating state of the engine.

FIG. 10 is a control map showing the relationship between R ₄ / R ₃ (R ₃ is the turning radius of Nicostop 6) set in the ROM of the control unit 21 and the engine speed. Along with this, the Nicostop 15 is displaced radially outward so that R ₄ / R ₃ approaches 1.

Now, the pedal portion 3 of the accelerator pedal 1 has a stroke S.
When the pedal is depressed with, the radius of rotation of the pedal portion 3 is R ₁ , the radius of rotation of the tip of the accelerator pedal to which the accelerator wire 4 is connected is R ₂ , or the radius of rotation of the Nicostop 11 with respect to the valve shaft 9 in the second drum 10. Is represented by r, the opening degree θt of the throttle valve 8 is expressed as θt = (1 / r) (R ₄ / R ₃ ) (R ₂ / R ₁ ) S.

Therefore, when the control unit 21 displaces the Nicostop 15 via the motor 19 etc. and increases R ₄ / R ₃ as the engine speed increases, as shown in FIG. 11, the depression amount of the accelerator pedal 1 is increased. The throttle valve opening θt becomes smaller with respect to the (stroke) S, and the maximum opening of the throttle valve 8 with respect to the full stroke S ₁ of the accelerator pedal 1 is θ ₂ , R when R ₄ / R ₃ = 1. ₄ / R ₃
When = 0.3, it is halved to θ ₁ . However, even if the throttle valve opening is half, the boost pressure rises to zero, so the engine output does not drop significantly.

As described above, when the amount of change in the throttle valve opening with respect to the stroke becomes small in the low rotation speed range when the accelerator pedal 1 starts to depress, a rapid increase in the intake air amount of the engine is suppressed. The rise of engine torque becomes smooth, and the longitudinal vibration applied to the vehicle during acceleration is suppressed.

(Problems to be Solved by the Invention) In such a device, if the throttle valve opening characteristic determined depending on the accelerator pedal opening and the engine speed is erroneously set at the time of setting or shifts due to a change over time. It may be difficult to drive at a constant speed.

This is because when the engine torque characteristic with respect to the engine speed has a positive slope as shown in FIG. 12, there may be no intersection with the rotation resistance curve, and at this time the accelerator pedal opening is kept constant. Even if you keep it
This is because the engine rotation goes up and down without permission. For example, considering the case where the engine speed slightly increases at the same accelerator pedal opening, according to the positive engine torque characteristic, the engine torque increases as the engine speed increases. The engine speed will rise further.

The present invention has been made in view of such conventional problems. The target throttle valve opening is set so that the characteristic of the generated torque at the same accelerator pedal opening with respect to the engine speed has a negative inclination, and the target throttle valve opening is set. It is an object of the present invention to provide a device that controls a throttle valve so that a valve opening degree is achieved.

(Means for Solving the Problems) In the present invention, as shown in FIG. 1, a sensor 31 for detecting the engine speed, a sensor 32 for detecting the accelerator pedal opening, and two sensors 31, 32 are used. Based on the detected value of, the means 33 that sets the target throttle valve opening so that the characteristic of the engine generated torque with the same accelerator pedal opening with respect to the engine speed has a negative slope, and the actual throttle valve opening is detected. Sensor 34, means 35 for outputting a control signal based on the sensor detection value so that the actual throttle valve opening matches the target throttle valve opening, and the throttle valve is driven in response to this control signal. And a device 36 for

(Operation) According to the present invention, regardless of the setting of the throttle valve, the engine torque characteristic with respect to the engine speed has a negative slope that is not so sharp over the entire range.
Here, the engine rotation speed is negatively fed back to the rotation speed determined by the intersection of the engine torque curve and the positive rotation resistance curve with respect to the accelerator pedal opening at that time, and stabilizes at a constant rotation unless the accelerator opening is changed. Therefore, constant speed running is performed stably.

(Embodiment) FIG. 2 shows a system diagram in which the present invention is applied to a fuel injection type engine. The throttle valve 53 provided in the intake passage 52 is driven by the device shown in FIG. In other words, the control signal from the control unit 21 causes the Nicostop 15 to be displaced downward in the drawing in the low rotation speed range, which reduces the amount of change in the throttle valve opening with respect to the accelerator pedal opening.

54 is an accelerator pedal opening sensor, which outputs according to the amount of depression of the accelerator pedal. Reference numeral 55 is a distributor in which a crank angle sensor 56 is incorporated, and the crank angle sensor 56 outputs a signal for each unit angle of the crank angle and a signal for each reference position. From the signal for each unit angle, the control unit 70 counts this to obtain the engine speed.

57 is a throttle valve opening sensor, which outputs according to the actual opening of the throttle valve 53.

Reference numeral 70 denotes a control unit to which signals from these sensors 54, 56, 57 are input, and the throttle valve drive device 66 is used to control the throttle valve via the throttle valve drive device 66 according to the accelerator pedal opening and the engine speed detected by the sensors 54, 56. The opening is controlled (described later).

The control unit 70 includes other sensors (air flow meter 58, water temperature sensor 59, knock sensor 60, oxygen concentration sensor 61, vehicle speed sensor 62, battery 63, key switch 6
The signals from 4) are also input, and it goes without saying that the control unit 70 performs various engine controls (fuel injection control and ignition timing control) based on these signals.

FIG. 3 is a block diagram when the control unit 70 is configured by a microcomputer. The input / output interface (I / O) 71, the CPU 72, the ROM 73, the RAM 74, and the RAM (which can retain the stored information even when the ignition key is turned off) BURAM)
75 and an A / D converter (ADC) 76 which converts an analog signal into a digital signal among various signals, and has the functions of the means 33 and 35 shown in FIG. Here, the two control units 21 and 70 are configured by separate microcomputers, but they may be configured by a single microcomputer.

In order to stabilize the constant speed running, it is desirable that the engine torque characteristic at the same accelerator pedal opening with respect to the engine speed has a not so steep negative slope as shown in FIG.

The reason why it has a negative slope is that it necessarily intersects with the rotation resistance curve having a positive slope. For example, consider a case where the engine speed slightly increases while the accelerator pedal opening is kept constant. If the torque characteristic has a negative slope, the engine torque will increase as the engine speed increases. Head towards decreasing. As a result, the engine speed decreases. On the contrary, when the engine speed slightly decreases, the engine torque correspondingly increases, and the engine speed increases. This means that as long as the accelerator pedal opening at that time is maintained, the engine speed at the intersection of the negative engine torque curve determined by the accelerator pedal opening and the positive rotation resistance curve is the engine speed at that time. It stabilizes.

However, even in the conventional example shown in FIG. 8, the engine torque characteristic still has a negative slope. However, in the conventional example, the amount of change in the throttle valve opening with respect to the accelerator pedal opening cannot be changed, so the negative slope is too steep in the low speed range, and it is difficult to control the engine torque in this speed range. In other words, in order to easily perform constant-speed traveling and to easily control the engine torque, it is necessary to have a negative slope that is not too steep over the entire range. For the first time, the engine torque can be made to have a gentle negative characteristic as shown in FIG. 5, using the device shown in FIG.
It is possible to freely obtain a characteristic just between those shown in FIGS. 12 and 8.

However, if there is a deviation in the setting of the throttle valve 53, the characteristics shown in FIG. 12 can be easily obtained. In order to avoid this, the throttle valve opening that satisfies the characteristics shown in FIG. 5 is determined in advance, and the actual throttle valve opening is monitored using this as a target value (target throttle valve opening). .

Here, between the throttle valve opening, the engine speed and the engine generated torque, as shown in FIG. 6, when the ratio of the throttle valve opening and the engine speed increases, the generated torque increases. Therefore, if this is used to rewrite FIG. 5, the characteristics shown in FIG. 7 can be obtained. From this, it is preferable to control the actual throttle valve opening with the throttle valve opening determined in FIG. 7 as the target value.

FIG. 4 shows a program executed by the CPU 72 of the microcomputer. For P ₁ and P ₂ , the accelerator pedal opening sensor 54
And the detected values from the crank angle sensor 56 are read, and the target throttle valve opening is set in P ₃ according to these detected values. The contents of the target throttle valve opening are as shown in FIG. 7. For example, the contents shown in FIG. 7 are made into a table and stored in the ROM 73 by using the accelerator pedal opening and the engine speed as parameters, and a table lookup is performed. To read.

At P ₄ , the actual throttle valve opening detected by the throttle valve opening sensor 57 is read, and at P ₅ , a control signal is sent to the throttle valve drive device 66 so that the actual throttle valve opening matches the target throttle valve. Output. The drive device 66 opens and closes the throttle valve 53 by an amount corresponding to this control signal. The control for detecting the actual throttle valve and matching it with the target throttle valve is feedback control.

To describe the operation of this embodiment, the throttle valve
Regardless of the setting of 53, it is possible to obtain the characteristic shown in FIG. 5 (the characteristic that the engine torque characteristic with respect to the engine speed has a negative slope that is not so steep over the entire range). Here, the engine rotational speed is negatively fed back to the engine torque curve for the accelerator pedal opening at that time, and the rotational speed determined by the intersection of the rotation resistance curve, and settles to a constant rotation unless the accelerator pedal opening is changed. It is possible to easily run at a constant speed.

(Advantages of the Invention) The present invention determines the target throttle valve opening such that the engine torque characteristic at the same accelerator pedal opening with respect to the engine speed has a negative inclination, and the throttle is adjusted to this target throttle valve opening. Since the valve is controlled, constant speed running can be easily performed regardless of the setting of the throttle valve.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram corresponding to claims of the present invention, FIG. 2 is a system diagram of a control system according to an embodiment of the present invention, and FIG. 3 is a block diagram of a control unit 70 shown in FIG. FIG. 4 is a flow chart for explaining the calculation contents of this embodiment, FIG. 5 is a diagram of the engine torque characteristic with respect to the engine speed of this embodiment, and FIG. 6 is a throttle valve opening, engine speed and engine. FIG. 7 is a characteristic diagram of the target throttle valve opening of the above-mentioned embodiment, FIG. 8 and FIG.
FIG. 12 is a characteristic diagram of engine torque of the conventional example. FIG. 9 is a block diagram of a throttle valve control device of the prior application,
FIG. 10 is a characteristic diagram of R ₄ / R _{3 with} respect to the engine speed of the earlier application, and FIG. 11 is a characteristic diagram of the throttle valve opening with respect to the accelerator pedal stroke of the earlier application. 1 ... accelerator pedal, 4 ... accelerator wire, 5 ...
1st drum, 8 ... Throttle valve, 10 ... Second drum, 12 ... Throttle wire, 15 ... Nicostop, 16
…… Guide groove, 17 …… Reciprocating rod, 18 …… Link, 19…
… Motor, 21 …… Control unit, 31 …… Engine speed sensor, 32 …… Accelerator pedal opening sensor, 33
...... Target throttle valve opening setting means, 34 ...... Throttle valve opening sensor, 35 ...... Feedback control means, 36 ...... Throttle valve drive device, 53 ...... Throttle valve, 54 ...... Accelerator pedal opening sensor, 56 ...... Crank angle sensor, 57 …… Throttle valve opening sensor,
66: Throttle valve drive device, 70: Control unit.

Claims (1)

[Claims] 1. A sensor for detecting an engine speed, a sensor for detecting an accelerator pedal opening, and a value of an engine generated torque at the same accelerator pedal opening for an engine speed based on detection values from these two sensors. A means for setting the target throttle valve opening so that the characteristic has a negative slope, a sensor for detecting the actual throttle valve opening, and the actual throttle valve opening is based on the sensor detection value. A throttle valve control device for an engine, comprising: means for outputting a control signal so as to match the opening degree; and a device for receiving the control signal and driving the throttle valve.