JPH0577868B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a device for controlling the opening of a throttle valve in an internal combustion engine for a vehicle.

[Prior art]

In a conventional vehicle internal combustion engine, for example, as shown in FIG. 7, an accelerator pedal 21 and a throttle valve 22 are directly mechanically connected via a wire 23 or the like, and the amount of operation (depression amount) of the accelerator pedal is Normally, this becomes the adjustment amount for the throttle valve.

In addition, as described in the published patent publication No. 107925 of 1982, the amount of operation of the accelerator pedal is detected electrically, and fuel is supplied accordingly, so that the amount of air commensurate with the fuel is supplied. A device is also known that controls a throttle valve to supply an air-fuel mixture to an engine in accordance with the operation of an accelerator pedal.

However, in the conventional throttle control device as described above, the throttle valve intervention degree is uniquely determined and operated based on the amount of operation of the accelerator pedal, so the following problems occur. .

[Problem that the invention seeks to solve]

In the case where the operating amount of the accelerator pedal and the throttle valve opening are uniquely determined as described above, what can be controlled by the accelerator pedal is the torque at the current rotational speed.

Therefore, when the accelerator pedal is depressed, a corresponding torque is generated, and if this torque is greater than or equal to the value required to maintain the current rotational speed, the rotational speed increases and thus acceleration is possible.

However, as a characteristic of an internal combustion engine, when the throttle valve opening remains the same, the torque decreases as the rotational speed increases.

For example, as shown by _the solid line in _{FIG .}
When increasing the throttle valve opening _to
It increases to θ ₂ at t ₁ and maintains that value.

The torque generated in this case has a characteristic that, as shown by the solid line C, it increases rapidly from time _t1 , but then gradually decreases as the rotational speed increases.

As mentioned above, in conventional devices, when the driver depresses the accelerator pedal in an attempt to accelerate and holds the pedal in the depressed position, the torque increases as the rotational speed increases, even though the driver desires the same acceleration. As the torque decreases, the acceleration also decreases, so the driver presses down on the accelerator pedal to increase the throttle valve opening as shown by the broken line in Figure 6, thereby maintaining the torque at the same level. I needed to.

As mentioned above, in conventional devices, the output characteristics of the internal combustion engine are not appropriate for the amount of operation of the accelerator pedal, so it is necessary to delicately control the accelerator pedal based on the driver's judgment. There was a problem that it was difficult to operate.

The present invention aims to solve the problems of the prior art as described above.

[Means for solving problems]

In order to achieve the above object, in the present invention,
When the driver operates the accelerator to accelerate and maintains the amount of operation, the throttle valve opening is increased over time to compensate for the decrease in torque that accompanies the increase in rotational speed. , is configured so that you can enjoy a constant sense of acceleration.

FIG. 1 is a block diagram illustrating the functionality of the present invention.

In FIG. 1, the operation amount detection means 1 detects the operation amount of an accelerator means (an accelerator pedal operated by the foot, an accelerator bar operated by the hand, etc.), and, for example, detects the amount of depression of the accelerator pedal. It is a potentiometer.

Further, the target opening degree setting means 2 sets a target throttle valve opening degree corresponding to the above-mentioned operation amount.

Next, the state detection means 3 is means for detecting when the operation amount is increased or maintained, that is, when the driver desires acceleration.

Next, the extra amount setting means 4 is a means for setting an extra amount that increases the throttle valve opening degree at a predetermined rate over time when the operation amount is increased or maintained.

Next, the opening command value generating means 5 outputs an opening command value obtained by adding the value set by the target opening setting means 2 and the value set by the additional amount setting means 4.

Next, the control means 6 controls the opening degree command value so that it does not exceed a predetermined upper limit value.

Next, the drive means 7 is a device that controls the throttle valve opening according to the opening command value limited by the above-mentioned control means.

The additional amount in the additional amount setting means 4 may be a constant value, but it is better to set the additional amount to a larger value as the above-mentioned manipulated variable is larger, so that the operation can be adapted to the characteristics of the engine.

[Embodiments of the invention]

FIG. 2 is a block diagram of one embodiment of the present invention.

In FIG. 2, a potentiometer 11 outputs an analog voltage corresponding to the amount of depression of an accelerator pedal (not shown), and corresponds to the operation amount detection means 1 in FIG. 1.

The arithmetic unit 12 is composed of, for example, an AD converter, a microcomputer, a DA converter, etc., and has functions corresponding to 2 to 6 in FIG. Outputs a command signal.

The drive circuit 13 drives the servo motor 14 in response to the above command signal.

The throttle valve 1 is controlled by this servo motor 14.
Controls the opening degree of 6.

Further, 15 is a potentiometer that outputs an analog voltage corresponding to the opening degree of the throttle valve 16, and controls the opening degree of the throttle valve 16 by feeding it back to the drive circuit 13 to match the opening degree of the throttle valve 16 with the command signal. It is something to do.

The above-mentioned 13 to 15 are the driving means 7 of FIG.
corresponds to

Next, the calculation performed by the above calculation device 12 will be explained.

FIG. 5 is a flowchart of one embodiment of the above calculation.

This calculation is repeated at predetermined timing.

In FIG. 5, first, the accelerator operation amount L is read at P1.

Next, in P2, a target throttle valve opening degree θ _a and an upper limit value θ _b corresponding to the accelerator operation amount L are calculated.

Both θ _a and θ _b are stored in advance in the form of a data table corresponding to the accelerator operation amount L.
A value corresponding to the amount of accelerator operation at that time is read out.

Above target throttle valve opening θ _a and upper limit value θ _b
has characteristics as shown in FIG. 3, for example.

In FIG. 3, a solid line a shows the characteristics of the target throttle valve opening θ _a , and a broken line b shows the characteristics of the upper limit value θ _b .

For example, when the accelerator operation amount is _l1 , the target throttle valve opening _θa is _a1 , and the upper limit value of the throttle valve opening at that time is _b1 .

Next, in P3, the operation amount detected in this calculation
It is determined whether L _o is greater than or equal to the previous operation amount L _o-1 .

If YES in P3, that is, the current value is equal to or greater than the previous value, that is, if the acceleration state is present, go to P4.

In P4, a unit additional amount Δθ of the throttle valve opening corresponding to the accelerator operation amount L (an amount added for each calculation) is calculated.

The value of Δθ is, for example, as shown in FIG.
It is appropriate to increase the value as the accelerator operation amount increases.

Note that this unit additional amount Δθ is also the accelerator operation amount L.
What is necessary is to read from a data table stored in advance in a form corresponding to the data table.

Next, in P5, the additional amount θ _o is calculated.

This θ _o is the value obtained by adding the unit additional amount Δθ to the previous value θ _o-1 .

That is, the extra amount increases by the unit extra amount Δθ for each calculation. As described above, the unit additional amount Δθ increases according to the accelerator operation amount, so the increase acceleration of the additional amount increases as the accelerator operation amount increases.

Next, in P6, the opening command value θ is calculated.

The opening command value θ is the target throttle valve opening θ _a plus the above-mentioned additional amount θ _o .

Next, in P7, the extra amount θ _o is stored as θ _o-1 for the next calculation.

Next, in P8, it is determined whether the opening command value θ is less than or equal to the upper limit value θ _b .

If P8 is YES, the value of θ is output as is.

If NO in P8, that is, if the calculated value of θ is greater than the upper limit value θ _b , the process goes to P9 and outputs θ as θ _b .

On the other hand, if NO in P3, that is, if it is not in an acceleration state, go to P10, set the target throttle valve opening θ _a at that time as the opening command value θ, and then:
Go to P11 and clear the extra amount θ _o to 0.

Next, the operation in the above calculation will be explained based on FIG. 6.

In FIG. 6A, as shown by the solid line, consider the case where the accelerator operation amount is _l1 , and the driver depresses the accelerator to _l2 at time _t1 , desiring acceleration.

To simplify the explanation, it is assumed that the accelerator operation amount is increased to _l2 and is held constant.

In this case, the target throttle valve opening degree θ _a will have a constant value if the accelerator operation amount is maintained at a constant value.

On the other hand, the unit additional amount Δθ added for each calculation
is calculated using the characteristics shown in FIG. 4, for example,
Since the value is added for each calculation, the additional amount θ _o gradually increases.

Therefore, the opening command value, which is the sum of the target throttle valve opening θ _a and the additional amount θ _o , gradually increases as shown by the broken line in FIG. 6B, and the throttle valve opening also increases accordingly.

Therefore, the torque has a characteristic as shown by the broken line in FIG. 6C, and it is possible to correct the decrease in torque due to the increase in the rotational speed.

Note that the opening command value is limited to the upper limit shown by the broken line b in Figure 3, so even if the accelerator operation amount is held at a constant value for a long time, the throttle valve opening will remain at the upper limit. It will not increase further.

〔Effect of the invention〕

As described above, in the present invention, the opening command value for setting the throttle valve opening is configured to increase over time even if the amount of operation of the accelerator remains the same. When the engine is operated and held, it is possible to correct the decrease in torque that accompanies the increase in rotational speed. Therefore, the driving operation becomes easier, and there is an effect that driving the vehicle becomes easier.

[Brief explanation of drawings]

Figure 1 is a block diagram showing the functions of the present invention, Figure 2 is a block diagram showing the functions of the present invention.
The figure is a block diagram of an embodiment of the present invention, Figure 3 is a characteristic diagram of accelerator operation amount and target throttle valve opening, and Figure 4 is a characteristic diagram of accelerator operation amount and unit additional amount Δθ of throttle valve opening. 5 is an example of a flowchart showing calculations in the device of the present invention, FIG. 6 is a characteristic diagram of accelerator operation amount, throttle valve opening and torque, and FIG. 7 is an example of a conventional device. be. Explanation of symbols: 1...Operation amount detection means, 2...Target opening setting means, 3...State detection means, 4...Additional amount setting means, 5...Opening command value generation means, 6...
. . . control means, 7 . . . drive means, 11 . . . potentiometer, 12 . . . calculation device, 13 . . . drive circuit, 14 .

Claims (1)

[Scope of Claims] 1. Operation amount detection means for detecting the operation amount of the accelerator means, target opening degree setting means for setting a target throttle valve opening degree corresponding to the operation amount, and a state in which the operation amount is increased or maintained. additional amount setting means for setting an additional amount to increase the throttle valve opening at a predetermined rate over time when the operation amount is increased or maintained, and the target opening opening command value generation means for outputting an opening command value obtained by adding the value set by the setting means and the value set by the additional amount setting means; 1. A vehicle throttle control device comprising: a limiting means for limiting the opening degree so as not to exceed a set upper limit; and a driving means for controlling the throttle valve opening according to the opening command value limited by the limiting means. 2. The vehicle throttle control device according to claim 1, wherein the additional amount setting means sets the increasing speed of the additional amount to a larger value as the operation amount increases. .