JP2550152B2 - Throttle control device in vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a throttle control device for a vehicle.

[Prior Art] Conventionally, when the driver inadvertently depresses the accelerator pedal, the output of the engine sharply increases and the vehicle suddenly starts. To prevent this, in vehicles that can detect the accelerator pedal depression amount and adjust the throttle opening amount according to the pedal depression amount, the throttle opening amount corresponding to the accelerator pedal depression amount and the actual throttle opening amount can be adjusted. There is a thing to prevent the sudden start by opening the throttle slowly when the difference with the degree is large.

[Problems to be Solved by the Invention] However, in the above-mentioned device, when the accelerator pedal is depressed from a state where the accelerator pedal is released and the vehicle is running by inertia, similarly, the throttle slowly opens slowly and acceleration is delayed to the driver. It gave a strange feeling.

An object of the present invention is to prevent a sudden start when the driver inadvertently depresses the accelerator pedal, and improve the traveling feeling without causing an acceleration delay even when the accelerator pedal is depressed from the inertia traveling state. It is to provide a throttle control device in a vehicle capable of performing the above.

[Means for Solving the Problem] In order to achieve the above object, the present invention provides a pedal depression for detecting the accelerator pedal depression amount in a vehicle in which the throttle opening of the carburetor is adjusted according to the accelerator pedal depression amount. An amount detecting means, a throttle opening adjusting means for adjusting the throttle opening, a running state detecting means for detecting a running state of the vehicle, a storage means for storing a reference throttle opening corresponding to the running state of the vehicle, When it is detected by the pedal depression amount detecting means that the accelerator pedal is operated, a judging means for judging whether the accelerator pedal has been operated in an acceleration direction or a deceleration direction, and the judging means accelerates the accelerator pedal. When it is determined that the vehicle is operated in the direction, the traveling state at that time is determined based on the data stored in the storage means. The reference throttle opening corresponding to the running state of the vehicle is calculated by the output means, and the throttle opening is increased at the first set speed which is the fast throttle opening change speed until the reference throttle opening is reached. The throttle opening adjusting means is controlled so as to be controlled, and thereafter, the throttle opening is driven in a direction in which the throttle opening increases at a second set speed that is a throttle opening change speed slower than the first set speed. As described above, when it is determined by the first control means for controlling the throttle opening adjustment means and the determination means that the accelerator pedal is operated in the deceleration direction, the throttle opening is always reduced at the third set speed. A throttle control device for a vehicle, comprising: a second control means for controlling the throttle opening adjustment means so that the throttle control means is driven in one direction. It is a summary.

[Operation] When the determination means determines that the accelerator pedal is operated in the acceleration direction, the first control means determines the traveling state of the vehicle by the traveling state detection means at that time based on the data stored in the storage means. Throttle opening adjustment is performed so that the corresponding reference throttle opening is calculated, and the throttle opening is driven in the direction in which the throttle opening increases at the first set speed that is the fast throttle opening change speed until the reference throttle opening is reached. The throttle opening adjusting means is controlled so that the throttle opening adjusting means is driven in a direction in which the throttle opening increases at a second set speed that is a throttle opening change speed slower than the first set speed. .

On the other hand, when the determination means determines that the accelerator pedal has been operated in the deceleration direction, the second control means always operates the throttle opening so that the throttle opening is driven in the direction in which the throttle opening becomes smaller at the third set speed. Control the degree adjusting means.

[Embodiment] An embodiment in which the present invention is embodied in a forklift having an automatic transmission with a dry single plate clutch will be described with reference to the drawings.

FIG. 1 shows the mechanism and electrical configuration of the drive system of the forklift, the output of the engine 1 is transmitted to the automatic transmission 3 via the dry single-plate clutch 2 and the drive wheels for traveling via the differential gear mechanism 4. 5 is moved forward and backward with a predetermined gear ratio. The connection state of the dry single plate clutch 2 for turning on and off the output of the engine 1 is adjusted relative to the stroke amount of the rod 6a extending based on the drive of the clutch control actuator 6. The stroke detection sensor 7 is composed of a potentiometer, detects the stroke amount of the rod 6a of the clutch control actuator 6, converts the detection signal into a digital signal by the A / D converter 8, and outputs the digital signal to the input / output interface 9. It

As shown in FIG. 2, the carburetor 10 has a rotary shaft 12 mounted in a carburetor air flow pipe 11 and a throttle butterfly 13 fixed to the rotary shaft 12.
A cam 14 fixed to one end of the rotary shaft 12 so as to rotate integrally with the rotary shaft 12 is urged to rotate counterclockwise in FIG. 2 by a spring (not shown). A cable 15 is connected to the cam 14. One end of the cable 15 is connected to a stepping motor 16 as throttle opening adjusting means, and the opening of the throttle butterfly 13, that is, the throttle opening is adjusted in proportion to the rotation amount of the motor 16. Has become.

An accelerator opening sensor 17 as a pedal depression amount detecting means is composed of a potentiometer and detects the depression amount of an accelerator pedal 18 provided in the driver's seat. Then, the signal is adapted to be converted into a digital signal by the A / D converter 19. Input shaft 3a of the automatic transmission 3
Is provided with an input shaft rotation speed sensor 20 as a traveling state detecting means, the rotation speed of the input shaft 3a is detected by the sensor 20, and the detection signal is output to the input / output interface 9.

The lever position detection sensor 21 is composed of a plurality of limit switches, detects the switching state (forward, neutral, reverse) of the forward / backward lever 22 provided in the driver's seat and outputs the signal to the input / output interface 9.

The microcomputer 23 as the judging means, the first controlling means and the second controlling means is a central processing unit (hereinafter, CPU).
24), a program memory 25 as a storage means composed of a read-only memory (ROM), and a working memory 26 composed of a readable / rewritable memory (RAM) in which the calculation processing result of the CPU 24 is temporarily stored. ing. Then, the CPU 24 operates based on the control program stored in the program memory 25. The CPU 24 inputs detection signals from the sensors 7, 17, 20, 21 via the input / output interface 9. The CPU 24 detects the amount of depression of the accelerator pedal 18 by the accelerator opening sensor 17 and calculates the throttle opening corresponding to the amount of depression of the accelerator pedal 18. And CPU24 is usually the accelerator pedal 1
The stepping motor 16 is driven and controlled so that the throttle opening corresponds to the depression amount of 8, and thus the throttle control, that is, the throttle opening is controlled.

Further, the CPU 24 drives and controls the clutch control actuator 6 via a clutch actuator drive circuit 27. Further, the CPU 24 uses the detection signal from the lever position detection sensor 21 to move the forward / backward lever 22 at that time.
In addition to indexing the operating position, the gear of the automatic transmission 3 is switched to the target gear position via the gear switching actuator drive circuit 28 according to the vehicle speed. The CPU 24 engages and disengages the dry single plate clutch 2 during the gear change control.

The program memory 25 stores in advance the data (map) shown in FIG. This data is data (characteristic line Lo) indicating the reference throttle opening θTH corresponding to the rotation speed Ni of the input shaft 3a of the automatic transmission 3. This data (characteristic line Lo) is obtained experimentally, and is used when the accelerator pedal 18 is operated.
Optimal reference throttle opening θTH according to the rotation speed Ni of 3a
Was decided.

Next, the operation of the throttle control device thus configured will be described with reference to FIG.

When the CPU 24 detects that the accelerator pedal 18 has been depressed by a predetermined amount, the CPU 24 compares the throttle opening corresponding to the pedal depression amount with the actual throttle opening (step 1). When the throttle opening corresponding to the pedal depression amount does not match the actual throttle opening, the CPU 24 next determines whether the throttle opening corresponding to the pedal depression amount is equal to or larger than the actual throttle opening or less ( Step 2). When the CPU 24 determines in step 2 that the throttle opening corresponding to the pedal depression amount is larger than the actual throttle opening, the reference corresponding to the rotation speed Ni of the input shaft 3a at that time based on the characteristic line Lo shown in FIG. The throttle opening TH is obtained (for example, the reference throttle opening TH1 for the rotation speed Ni1) (step 3).

The CPU 24 compares the reference throttle opening TH with the actual throttle opening (step 4), and when the actual throttle opening is less than the reference throttle opening TH, the speed is high. The stepping motor 16 is driven to open the throttle at the (first set speed) (step 5). When the actual throttle opening is equal to or larger than the reference throttle opening TH in step 4, the CPU 24 opens the throttle at the second throttle opening changing speed (second setting speed) which is slower. Are driven (step 6).

When the CPU 24 determines in step 2 that the throttle opening corresponding to the pedal depression amount is equal to or smaller than the actual throttle opening, it drives the stepping motor 16 to close the throttle at the set speed (third set speed). (Step 7).

As described above, in this embodiment, when the accelerator opening sensor 17 detects that the accelerator pedal 18 is operated by a predetermined amount, the third state corresponding to the traveling state (the rotation speed of the input shaft 3a) by the input shaft rotation speed sensor 20 is detected. Controls the stepping motor 16 that calculates the reference throttle opening TH of the map (characteristic line Lo) shown in the figure and adjusts the throttle opening so that the throttle opening change speed is fast until the reference throttle opening TH is reached. At the same time, the stepping motor 16 is controlled so that the throttle opening change speed becomes slower. Therefore, when the vehicle is stopped, the accelerator pedal 18 is inadvertently depressed, and at that time, the rotation of the input shaft 3a is low (the traveling speed is slow) and the reference throttle opening TH is small, so that the throttle does not open slowly and the coasting does not start rapidly Even if the accelerator pedal 18 is depressed from the running state, the rotation of the input shaft 3a at that time is high (the running speed is high) and the reference throttle opening TH
Is also set to a large value, so that the throttle can be opened quickly and the driving feeling can be improved without causing an acceleration delay. In particular, in an industrial vehicle such as a forklift that carries out cargo-handling work, even if the driver inadvertently depresses the accelerator pedal 18, a proper acceleration can be obtained without a sudden start and the collapse of the cargo can be prevented.

Also, when the accelerator pedal 19 is operated in the deceleration direction, it prevents a sudden start from the vehicle stop state as seen when operating in the acceleration direction and improves the driving feeling when the accelerator pedal 18 is depressed from the inertia running state. In light of the fact that the problem of
Only when 19 is operated in the acceleration direction, two types of throttle opening speeds are provided and appropriately controlled, and when the accelerator pedal 19 is operated in the deceleration direction, throttle opening is controlled by only one kind of set speed. Since this is done, the control system can be simplified as a whole. Moreover, since the throttle opening is controlled only by either the first set speed, the second set speed, or the set speed (third set speed), it is easy and easy to determine the change speed of the throttle opening. It can be done quickly.

The present invention is not limited to the above embodiment, but in the above embodiment, the input shaft rotation speed sensor 20
Detected the running condition of the vehicle and controlled the throttle,
The throttle control may be performed by obtaining a signal corresponding to the traveling speed with another sensor.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to prevent a sudden start when the driver inadvertently depresses the accelerator pedal, and to delay the acceleration even if the accelerator pedal is depressed from a coasting state. It is possible to improve the driving feeling without causing the noise. In addition, when the accelerator pedal is operated in the deceleration direction, it is possible to prevent sudden start from the vehicle stop state that is seen when operating in the acceleration direction, and to improve the traveling feeling when the accelerator pedal is depressed from the inertia traveling state. In view of the absence of problems, two kinds of throttle opening speeds are provided and appropriately controlled only when the accelerator pedal is operated in the acceleration direction, and when the accelerator pedal is operated in the deceleration direction, the throttle opening is opened. Is controlled only by one kind of set speed, the control system can be simplified as a whole. Moreover, since the throttle opening is only controlled at any one of the first set speed, the second set speed, and the third set speed, the change speed of the throttle opening can be easily and quickly determined. You can

[Brief description of drawings]

FIG. 1 is a diagram showing the mechanism and electrical configuration of a forklift drive system embodying the present invention, FIG. 2 is a diagram showing a carburetor, and FIG. 3 is a diagram showing the relationship between the input shaft rotational speed and the reference throttle opening. FIG. 4 and FIG. 4 are flowcharts showing the operation of the throttle control device of this embodiment. Reference numeral 10 is a carburetor, 16 is a stepping motor as throttle opening adjusting means, 17 is an accelerator opening sensor as a pedal depression amount detecting means, 18 is an accelerator pedal, 20 is an input shaft speed sensor as a running state detecting means, 23 Is a microcomputer as the judging means, the first controlling means and the second controlling means, and 25 is a program memory as the storing means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichi Hatake 1015 Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture, Fujitsu Limited (56) References JP-A-1-277656 (JP, A)

Claims (1)

(57) [Claims] 1. A vehicle in which a throttle opening of a carburetor is adjusted in accordance with an accelerator pedal depression amount, a pedal depression amount detecting means for detecting an accelerator pedal depression amount, and a throttle opening for adjusting the throttle opening amount. Degree adjusting means, a running state detecting means for detecting a running state of the vehicle, a storing means for storing a reference throttle opening corresponding to the running state of the vehicle, and an accelerator pedal operated by the pedal depression amount detecting means. When the accelerator pedal is operated in the acceleration direction or the deceleration direction, and when the accelerator pedal is operated in the acceleration direction by the determination means, the determination means determines whether the accelerator pedal is operated in the acceleration direction or the deceleration direction. Based on the data stored in the means, a reference slot corresponding to the running state of the vehicle by the running state detecting means at that time. Torr to calculate the degree of opening,
The throttle opening adjusting means is controlled so that the throttle opening is driven in the direction in which the throttle opening increases at the first set speed which is a fast throttle opening changing speed until the reference throttle opening is reached, and thereafter, the throttle opening adjusting means is controlled. First control means for controlling the throttle opening adjustment means so that the throttle opening is driven in a direction in which the throttle opening increases at a second set speed that is a throttle opening change speed slower than the first set speed; When it is determined by the determination means that the accelerator pedal is operated in the deceleration direction, the throttle opening adjustment means is controlled so that the throttle opening adjustment means is always driven in the direction in which the throttle opening becomes smaller at the third set speed. 2. A throttle control device for a vehicle, comprising: