JPH03229928A - Variable lever ratio throttle controller of internal combustion engine - Google Patents

Abstract

PURPOSE:To improve operability by connecting a first lever relatively rotatable to a throttle shaft according to operation of an acceleration pedal, to a second lever fixed to the throttle shaft via a middle lever which is displaced in the radial direction of the throttle shaft. CONSTITUTION:A second lever 6 having a pin 5 on its top end is fixed to one end, projected from the side wall of a throttle chamber, of a throttle shaft 3 fixed to a disk-shaped throttle valve 4 which is arranged across the intake passage of the throttle chamber, and also a sector-shape throttle drum 8 is rotatably fitted thereto. The end part of an acceleration wire 22 is fixed to the throttle drum 8, and also a first lever 10 having a pin 9 on its top end is fixed thereto. A middle lever 11 driven via a rod 15 and a guide ring 14 longitudinally by operation of an actuator 16 is interposed between respective levers 6, 10 so as to engage pins 9, 5 respectively with engaging holes 12, 13 formed in this middle lever 11.

Description

Detailed Description of the Invention (Field of Industrial Application) This invention relates to a device for opening and closing the throttle of an internal combustion engine, and in particular, to an apparatus for arbitrarily adjusting the characteristics between the amount of human accelerator pedal operation and the amount of actual throttle opening and closing. The present invention relates to a variable lever ratio throttle control device that can be changed.

(Prior Art) The throttle of an internal combustion engine, for example, the throttle valve of an automobile gasoline engine, is normally directly connected to the accelerator pedal via an accelerator wire, and the amount of operation of the accelerator pedal (depression) by the driver is directly connected to the accelerator pedal. The opening degree of the throttle valve is fixedly determined relative to the Therefore, when driving in traffic jams, delicate operation of the accelerator pedal is required, resulting in poor operability.

Therefore, in recent years, various throttle opening and closing devices have been proposed in which a throttle valve of an internal combustion engine is driven to open and close by an electric motor. With this type of device, the amount of operation of the accelerator pedal is detected as an electrical signal by a potentiometer, etc.
Based on this, an output signal from a control circuit drives an electric motor such as a pulse motor or a DC motor, and a throttle valve connected to the electric motor rotates. In other words, the accelerator pedal operated by the driver and the throttle valve are simply electrically connected, and the throttle valve is directly driven by an electric motor (for example, Japanese Patent Laid-Open No. 62-2142
Publication No. 41). Therefore, it is easy to change or correct the characteristics between the accelerator pedal operation amount and the throttle valve opening, and to control the output during slippage.

In addition, the present applicant links a first lever that rotates in conjunction with an accelerator pedal with a second lever fixed to a throttle shaft via an intermediate lever, and changes the rotational center position of this intermediate lever. By doing so, the first.
We have previously proposed a variable lever ratio type throttle opening/closing device that can change the lever ratio between the second lever, that is, the characteristics between the accelerator pedal operation amount and the actual throttle opening/closing amount (patent application 1-108156).

(Problem to be Solved by the Invention) In a configuration in which the characteristics between the accelerator pedal operation amount and the actual throttle opening/closing amount can be arbitrarily changed by changing the rotation center position of the intermediate lever as described above. For example, it is possible to provide optimal characteristics depending on the operating conditions such as engine speed and accelerator pedal operation amount. If it were to be moved, the torque change due to the change in characteristics may be quite large depending on the driving conditions, which may give the driver a sense of discomfort.

(Means for Solving the Problems) Therefore, the present invention provides an optimal moving speed depending on the vehicle driving conditions at that time. That is, the variable lever ratio throttle control device for an internal combustion engine according to the present invention is mechanically connected to a throttle shaft linked to a throttle of the internal combustion engine and an accelerator pedal, and has a rotation center substantially coaxial with the throttle shaft. a first lever rotatable relative to the throttle shaft as the accelerator pedal is operated, a second lever fixed to the throttle shaft, and linked to both the first lever and the second lever; The rotation of the first lever is
An intermediate lever that transmits transmission to the lever, a guide member that defines the rotation center position of this intermediate lever, a drive mechanism that moves this guide member in the radial direction of the throttle shaft, and a movement amount of the guide member by this drive mechanism that determines the amount of movement of the guide member during vehicle operation. The vehicle is configured to include means for setting the speed according to the conditions and means for setting the moving speed during the movement according to the vehicle driving conditions.

(Operation) When the driver operates the accelerator pedal, the first lever rotates, this rotation is transmitted to the second lever via the intermediate lever, the throttle shaft rotates, and the throttle opens. At this time, for example, if the rotation center of the first Lehart intermediate lever coincides with the axial center of the throttle shaft, the first
The rotation angle of the lever and the rotation angle of the second lever are equal.

On the other hand, if the center of rotation of the intermediate lever is eccentric from the center of the throttle shaft axis, the rotation angle of the first lever and the rotation angle of the second lever will be different, and the correlation between the two will depend on the amount of eccentricity. It changes accordingly.

That is, by appropriately moving the guide member using the drive mechanism, the characteristic between the accelerator pedal operation amount and the throttle opening degree can be varied.

Here, the amount of movement of the guide member that determines the above-mentioned characteristics is set so as to provide the optimum characteristics according to vehicle driving conditions such as engine speed and accelerator pedal operation amount. Further, the moving speed during this movement is also set depending on the vehicle driving conditions.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

Fig. 1 is a configuration explanatory diagram showing a control system of a variable lever ratio throttle control device according to the present invention, and Fig. 2 is an exploded perspective view showing a variable lever ratio type throttle opening/closing mechanism l used in this embodiment in an exploded state. , FIG. 3 is a sectional view showing the opening/closing mechanism 1 in an assembled state.

First, the throttle opening/closing mechanism 1 will be explained with reference to FIGS. 2 and 3.

In the figure, reference numeral 2 denotes a throttle chamber (not shown in FIG. 2) attached to the inlet of an intake collector (not shown), and a throttle shaft 3 passes through the throttle chamber 2 so as to cross the intake passage 2a. A disk-shaped throttle valve 4 is fixed to the throttle shaft 3. Further, one end of the throttle shaft 3 projects from the side wall of the throttle chamber 1, and a second lever 6 having a pin 5 at its tip is fixed to the base of the projecting part.

The throttle shaft 3 is always biased in one direction of rotation, specifically in the closing direction of the throttle valve 4, by a return spring 7 made of a coil spring, so that in the free state, the throttle valve 4 moves through the intake passage 2. It has become completely occluded.

As shown in FIG. 1, a throttle valve opening sensor 20 for detecting the actual opening β of the throttle valve 4 is attached to the other end of the throttle shaft 3.

A fan-shaped throttle drum 8 is rotatably fitted into the tip of the protruding portion of the throttle shaft 3, and is prevented from being removed by an E-ring 19. The throttle drum 8 includes an accelerator pedal 21
The end of the accelerator wire 22 (see FIG. 1) linked to the accelerator wire 22 (see FIG. 1) is fixed, and the accelerator wire 22 is wound around the concave groove 8a, and the It is designed to rotate.

Then, on the side of the throttle drum 8, there is a pin 9 at the tip.
A first lever 10 is fixed. Therefore, in this embodiment, the rotation center of the first lever lO coincides with the axial center of the throttle shaft 3.

+1 is an intermediate lever located between the first lever IO and the second lever 6, and this intermediate lever 11 has a short cylindrical bearing part 11a in the center,
Plate portions 11b, llc are extended from two locations 180 degrees apart, and each plate portion 11b, llc
Elongated engagement holes 12 and 13 are respectively formed in the openings. The pin 9 at the tip of the second lever 6 is inserted into one engagement hole I2, and the pin 5 at the tip of the second lever 6 is inserted into the other engagement hole 1.
3, respectively.

Further, the intermediate lever 11 is rotatably supported by its bearing portion 11a fitting into the outer periphery of a cylindrical guide ring 14 serving as a guide member. The guide ring 14 is formed integrally with a flange portion 15a at the tip of the control rod 15, and the intermediate lever 11 is placed between the snap ring 20 fitted in the groove 14a of the guide ring 14 and the flange portion 15a. is retained. The control rod 15 is linearly driven by an actuator 16 constituting a drive mechanism in the radial direction of the throttle shaft 3, specifically in a direction substantially along the longitudinal direction of the intermediate lever 11 when the throttle valve 4 is fully closed. It is now possible to do so. The actuator 16 is
For example, it has a built-in electric motor such as a pulse motor, and is configured to convert its rotational motion into linear motion using a screw or the like, and is fixed by a bracket 17. In addition, the flange portion 1 of the control rod 15
5a, an elongated shaft through hole 18 through which the throttle shaft 3 passes is formed along the movement direction of the control rod 15.

As shown in FIG. 1, the actuator 16 is driven and controlled by a control unit 23 consisting of, for example, a microcomputer system. The control unit 23 receives a detection signal from the throttle valve opening sensor 20 that detects the opening β of the throttle valve 4 described above. Further, in FIG. 1, 24 is the operation amount (depression angle) α of the accelerator pedal 21. 25 is a crank angle sensor that detects engine speed N; 26 is a vehicle speed sensor that detects vehicle speed V;
7 is a water temperature sensor that detects the cooling water temperature TW of the internal combustion engine;
8 indicates a gear position F (for example, 1st gear,
This is a gear position detection switch that detects 2nd speed, 3rd speed, etc.), and these detection signals are also manually input to the control unit 23. Note that the operation amount α of the accelerator pedal 21 is. corresponds uniquely to the rotation angle α of the first lever 10.

Next, the operation of the above configuration will be explained.

First, the principle of changing characteristics by the throttle opening/closing mechanism 1 will be explained with reference to FIG. 4.5.

In the above configuration, the second lever 6 is naturally centered around the throttle shaft 3 (its rotation center is 0 in FIGS. 4 and 5).
(shown as a point), and the first shaft 7<-10 similarly rotates around the throttle shaft 3, that is, the above-mentioned 0 point. Further, the intermediate lever 11 is rotatable about the center point of the guide ring 14 (shown as point 01 in FIG. 4.5). Note that while the 0 point is a fixed point, the 03 point, which is the center of the intermediate lever 11, is movable in the radial direction of the throttle shaft 3.

Therefore, when the accelerator pedal 21 is operated, the first lever 1
When the lever 0 rotates by an angle α corresponding to the amount of operation (depression amount), the intermediate lever 11 rotates in the same direction via the pin 9. This rotation of the intermediate lever I+ is transmitted to the second lever 6 via the pin 5, and the throttle valve 4 rotates together with the throttle shaft 3.

Here, if the center point O7 of the guide ring 14 coincides with the zero point, which is the center of the throttle shaft 3, as shown in FIG.
The three members in 1 rotate by exactly the same angle. For example, in FIG. 4, the first lever IO is at the minimum opening position A. The state in which the first lever 10 is rotated from the position where the amount of depression is 0 to the maximum opening position AI (the maximum depression position) is shown.
rotation angle α and the corresponding minimum opening position B of the second lever 6. The rotation angles β from to the maximum opening position B are equal to each other.

Therefore, the opening characteristic is the same as when the throttle drum 8 is directly attached to the throttle shaft 3.

On the other hand, if the center O3 of the guide ring 14 is eccentric to one side with respect to the zero point as shown in FIG. β has different values. For example, FIG. 5 shows an example in which point 01 is moved toward the pin 5 when the throttle valve 4 is fully closed, and the first lever 10 is moved to the minimum opening position A as in FIG. The figure shows the change when the second lever 6 is rotated from the maximum opening position A to the maximum opening position A, but the second lever 6 is at the minimum opening position B as shown. It can only rotate from to the maximum opening position B, and the rotation angle β
is smaller than the rotation angle α of the first lever 10.

Therefore, compared to the amount of operation of the accelerator pedal, the actual throttle valve 4
The change in the opening degree becomes smaller, resulting in characteristics suitable for driving in traffic jams, for example.

FIG. 6 is a schematic representation of the above configuration, and for ease of understanding, the lever radii from the rotation center 0 to the pin 5°9 are equal to each other, and the 01 point is A. It is assumed that the object moves along the line connecting the point and the 0 point. As can be understood from this figure, if the eccentricity from the 0 point of the lever radius of 1101 points is e, the rotation angle β of the second lever 6 (approximately equal to the opening degree of the throttle valve 4) is given as follows. can be shown. Note that in the actual layout, the first lever 10. Even if the lever radius of the second lever 6 is slightly different, or if the 01 point moves in a direction slightly deviated from the line passing through the Ao point and the 0 point, a similar relationship holds true. Further, the eccentricity e can be in both positive and negative directions.

Therefore, if the eccentricity e is appropriately variably controlled by the actuator 16, the opening characteristic between the accelerator pedal operation amount and the actual opening of the throttle valve 4 can be arbitrarily changed.

FIG. 7 is a main flowchart schematically showing the control of the eccentricity e, that is, the control of the actuator 16, executed in the control unit 23. To explain the control of the actuator I6 with reference to this figure, first, in step l, the operating conditions at that time, in detail, the first
The rotation angle α of the lever lO (corresponding to the operation amount of the accelerator pedal 21), the actual opening degree β of the throttle valve 4, and the engine speed N are read. In step 2, the target opening degree β of the throttle valve 4 is determined based on these operating conditions. is calculated. Then, the target opening degree β of this throttle valve 4. The target movement amount E of the actuator I6 necessary to obtain the above is set in step 3. Note that the current position of the actuator 16 at that time is α
It can be determined from the relationship between and β, and if a step motor is used, it can be determined from the number of steps.

Further, in step 4, a moving speed S is set in accordance with vehicle driving conditions, as will be described later. And in step 5,
Actuator 1 moves along the above target movement, IIEJ.
6 is driven at a set moving speed S.

FIG. 8 is a flowchart showing details of the moving speed setting process in step 4, which will be explained below.

First, in step 11-13, the engine speed N, the gear position F of the transmission, and the engine cooling water temperature TW are read as vehicle operating conditions. Then, in step 14, it is determined whether or not the cooling water temperature TW is higher than the predetermined temperature TWo, that is, whether or not it is warmed up to a certain extent.If it is lower than the predetermined temperature TWo, the step Proceeding to step 28, the lower speed SL is selected as the moving speed S. This is done in consideration of the fact that the idle speed is set high when the engine is at a low temperature, and there is a possibility that sudden torque fluctuations may occur due to movement of the actuator I6, that is, changes in the opening characteristic.

On the other hand, if the predetermined warm-up state is reached, the process proceeds to step 15 and subsequent steps. In step 15, the engine speed N is compared with a predetermined value N (for example, 300 (set to about 1-400 rpm)), and if the engine speed is greater than the predetermined value N, the flag n is set to 1 (step 16 ), a predetermined value N. If it is less than the flag n h < O (step 17).Similarly, in step 18, the gear position F is compared with a predetermined value F. (for example, 2nd gear), and if the speed is higher than Fo. If it is a gear, the flag f becomes 1 (step 19), and if it is a low speed 6 gear below Fo, the flag f becomes O (step 2).
0). Then, in step 21, b=n+f is determined.

That is, depending on the combination of flag n and flag f, the operating conditions are classified into the following four types: (1) to (2).

■n=0. f=o therefore b=.

This means that the vehicle is being driven at low speeds using a low gear, and is mainly applicable when driving in traffic jams.

Therefore, it is necessary to place emphasis on operability, and it is desirable that the moving speed be low.

■ n=o, f=1 Therefore, b=1 This means that the vehicle is operated at low rotation speed using a high-speed gear, and mainly applies to deceleration and coasting. Therefore, it is desirable that the moving speed be high in order to prepare for the next acceleration.

■ n=1. f=o Therefore, b=1 This means that the vehicle is being operated at high rotation speed using a low speed gear, and this mainly applies when the vehicle is accelerating. Therefore, in order to improve acceleration performance, it is desirable that the moving speed be high.

■ n=1. f=1 Therefore, b=2 This means that the vehicle is being driven at high speed using a high gear, and is considered to be mainly running at high speed. Therefore, in order to ensure high-speed drivability, it is desirable that the moving speed be low.

In step 22, it is determined whether or not the value of b obtained in step 21 is 1. If it is other than 1, the lower speed SL is selected as the moving speed S (step 28).
. In other words, in the case of (1) or (2) above, the speed becomes So on the low speed side for the reason mentioned above.

Further, in the case of (1) or (2) above, where b=1, the slip amount is further determined in step 23 and subsequent steps. That is, in step 23, the actual vehicle speed V is read from the detection signal of the vehicle speed sensor 26, and in the stable tab 24, the theoretical vehicle speed V' is calculated from the engine speed N and the gear ratio. Furthermore, step 2
In step 5, the slip amount ΔV is calculated as the difference between the two (ΔV=V--V).

This slip amount ΔV is then compared with a predetermined value ΔVo in step 26. Here, the predetermined value Δ■.

If the above slip is detected, it is considered that the road is low μ, and a sudden change in the opening characteristic is undesirable, so the process proceeds to step 28, and a lower moving speed SL is selected.

Moreover, if the slip amount ΔV is smaller than the predetermined value ΔVo,
It is in a grip state where torque is sufficiently transmitted to the road surface. In this case, SH on the high speed side is selected as the moving speed S (step 27).

That is, the high-speed SH is selected only under the conditions (1) or (2) described above and only when the slip is low.

In this way, by changing the moving speed of the actuator I6, that is, the changing speed of the opening characteristic according to various conditions, it is possible to improve acceleration performance and drivability in a low speed range without giving a sense of discomfort due to sudden changes in characteristics. I can do it.

Next, FIG. 9 is a flowchart showing a different embodiment of the moving speed setting process, which will be explained below. This is a data map lookup method to more precisely set the moving speed S, and in steps 31 to 34, the gear position F1 cooling water temperature TW, actual vehicle speed V, and engine speed N are read, respectively. Further, in step 35, the theoretical vehicle speed V' is calculated from the engine speed N and the gear ratio, and in step 36, the slip amount ΔV is calculated.
is calculated as ΔVV--V.

Then, in step 37, the corresponding moving speed SI is determined by lookup with reference to a data map using the gear position F, engine speed N, and throttle valve opening degree β as parameters. As an example, FIG. 10 shows the characteristics of the data map at the first gear position, and FIG. 11 shows the characteristics of the data map at the fourth gear position. As is clear from a comparison between the two figures, the rate of change in the moving speed S with respect to the change in the throttle valve opening degree β is greater in the low speed gear. This is done in consideration of the fact that when in low gear, acceleration and driving in traffic jams are the main activities, and when in high gear, there is a lot of steady driving, so it is necessary to place zero emphasis on drivability in steady state.

In addition, as a general rule, when the throttle valve opening degree β is large, the amount of movement E of the actuator 16 is generally large, so the movement speed S becomes large.
becomes large.

Next, in step 38, the corresponding moving speed S is determined by lookup with reference to a data map using the cooling water temperature TW, engine speed N, and throttle valve opening degree β as parameters. As an example, FIG. 12 shows the characteristics of the data map when the cooling water temperature TW is 40.degree. C., and FIG. 13 shows the characteristics of the data map when the cooling water temperature TW is 80.degree. Note that this data map is given for several representative cooling water temperatures TW.

Furthermore, in step 39, the slip amount ΔV and the engine speed N
The corresponding moving speed S3 is determined by lookup with reference to a data map using the throttle valve opening degree β as parameters. As an example, FIG. 14 shows the characteristics of the data map in a slip state in which the slip amount Δ■ is greater than the predetermined value Δvo, and FIG. 15 shows the characteristics of the data map in the non-slip state in which the slip amount Δ■ is less than the predetermined value ΔVo.

Finally, in step 40, the average of the above-mentioned moving speeds S, , S, .

S = w, x S ++Wtx S, +Wsx S
3 ((Wl+W't+W3-1) The reason for weighting in this way is that the importance and priority of each parameter are not uniform, and that the moving speed S is determined in a more optimal form that takes this into account. .

For example, W 1 = 0, 4, W2 = 0. LW3=0
．． It should be around 5.

(Effects of the Invention) As is clear from the above explanation, in the variable lever ratio throttle control device for an internal combustion engine according to the present invention, the moving speed of the drive mechanism that changes the lever ratio, that is, the amount of accelerator pedal operation and the amount of opening/closing of the throttle The speed of change in characteristics between the two is optimally set according to the vehicle driving conditions such as gear position, so that torque changes due to sudden changes in characteristics can be prevented under conditions where unexpected torque changes are undesirable. This will no longer occur, and the driver will not feel any discomfort.

[Brief explanation of drawings]

Fig. 1 is a configuration explanatory diagram showing one embodiment of a variable lever ratio throttle control device according to the present invention, Fig. 2 is an exploded perspective view of a throttle opening/closing mechanism used in this embodiment, and Fig. 3 is an exploded perspective view of the throttle opening/closing mechanism used in this embodiment. 4 is an explanatory diagram of the operation when the amount of eccentricity of the throttle opening/closing mechanism is O, FIG. 5 is an explanatory diagram of the operation when an appropriate amount of eccentricity is given, and FIG. 6 is the operating principle. An explanatory diagram for explaining, FIG. 7 is a flowchart showing an example of actuator control, and FIG.
9 is a flowchart showing details of the moving speed setting process, FIG. 9 is a flowchart showing another embodiment of the moving speed setting process, FIGS. 1θ, 11, 12, 13,
4 and 15 are characteristic diagrams showing examples of data maps of this embodiment, respectively. ■... Throttle opening/closing mechanism, 3... Throttle shaft, 4... Throttle valve, 6... Second lever 10...
First lever 11... Intermediate lever 14... Guide ring, 16... Actuator, 20... Throttle valve opening sensor, 21... Accelerator pedal, 23... Control unit, 24... Accelerator pedal angle sensor, 2
5... Crank angle sensor, 26... Vehicle speed sensor, 2
7...Water temperature sensor, 28...Gear position detection switch. 3S Hinato work γ seat 7 rotation speed N (rpm) work 7 work γ rotation speed N (rpm)

Claims (1)

[Claims] (1) A throttle shaft that is connected to the throttle of the internal combustion engine, is mechanically connected to the accelerator pedal, and has a rotation center approximately coaxial with the throttle shaft, and when the accelerator pedal is operated, the throttle shaft is connected to the accelerator pedal. a first lever that is relatively rotatable; a second lever fixed to the throttle shaft;
an intermediate lever that is linked to both levers and transmits the rotation of the first lever to the second lever; a guide member that defines the rotational center position of the intermediate lever; and a guide member that moves the guide member in the radial direction of the throttle shaft. A variable internal combustion engine comprising a drive mechanism, a means for setting the amount of movement of a guide member by the drive mechanism according to vehicle operating conditions, and a means for setting the speed of movement during this movement according to vehicle operating conditions. Lever ratio throttle control device.