JP2535795B2 - Maximum vehicle speed controller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a maximum vehicle speed control device suitable for a vehicle including a fluid coupling such as a torque converter.

(Prior Art) The maximum allowable vehicle speed is often legally regulated in each country. As a method of regulating the maximum vehicle speed of the vehicle, when the vehicle speed exceeds the allowable maximum vehicle speed, a method of stopping the fuel supplied to the internal combustion engine, and disabling the ignition device to prevent combustion in the cylinder Methods etc. are known.

(Problems to be Solved by the Invention) In order to determine that the vehicle speed has exceeded the allowable maximum vehicle speed, it has been conventionally determined only by the vehicle speed information from the vehicle speed sensor, but if it is determined only by the vehicle speed information, the torque converter ( Hereinafter, in a vehicle equipped with a fluid coupling such as "torque converter" (hereinafter referred to as "Turkish car"), the following inconvenience occurs. That is, this will be described with reference to FIG. 3. In the case of a torque converter vehicle, even when the vehicle speed exceeds the maximum permissible vehicle speed, even if the engine is not operated due to fuel stop or ignition stop (FIG. 3 (a)). The engine becomes inoperable at time t1), the effect of engine braking is poor due to the slip phenomenon peculiar to the torque converter, and the vehicle maintains the vehicle speed exceeding the allowable maximum vehicle speed due to inertia for a while. On the other hand, the engine speed also sharply decreases due to the torque converter slip phenomenon.

Next, when the vehicle speed falls across the allowable maximum vehicle speed (time t2 in FIG. 3 (a)), when the operation of the engine is restarted by starting fuel supply or the like, the engine speed rapidly rises (second time). A large feeling of acceleration is generated as shown in FIG.

If such a phenomenon is repeated every time the engine speed changes across the allowable maximum vehicle speed, the vehicle speed and the engine speed hunt heavily, and a good driving feeling cannot be obtained.

Whether or not the vehicle speed exceeds the maximum allowable vehicle speed is set by setting the determination rotation speed corresponding to the maximum allowable vehicle speed, and instead of the vehicle speed, it is determined whether the engine rotation speed exceeds this determination rotation speed. Due to the slip phenomenon of the torque converter, the relationship between the vehicle speed and the engine speed is not uniquely determined, and it has been difficult to control the maximum vehicle speed using the conventional engine speed information.

The present invention has been made to solve such a problem, and provides a maximum vehicle speed control device capable of controlling the vehicle speed to be equal to or lower than the maximum allowable vehicle speed without causing hunting of the vehicle speed and the engine speed. With the goal.

(Means for Explaining Problems) According to the present invention in order to achieve the above-mentioned object, according to the present invention, a vehicle speed detecting means for detecting a vehicle speed of a vehicle equipped with an internal combustion engine, and the internal combustion engine according to the detected vehicle speed. Determining means for determining whether or not the engine should be inactivated, and outputting an operation stop signal when the internal combustion engine should be inactivated; and an engine for stopping the operation of the internal combustion engine in response to the operation stop signal In a maximum vehicle speed control device that includes a non-operation means and that regulates a vehicle speed to be equal to or lower than a set maximum allowable speed, a release vehicle speed storage unit that stores in advance a release vehicle speed smaller than the maximum allowable vehicle speed, and a rotation speed of the internal combustion engine. Rotation speed detection means for detecting, vehicle speed arrival determination means for determining that the detected vehicle speed has reached the allowable maximum vehicle speed, and it has been determined that the vehicle speed has reached the allowable maximum vehicle speed The engine speed detected at this time is provided as a determination engine speed storage means for storing as a determination engine speed, the determination means, after determining that the vehicle speed has reached the maximum allowable vehicle speed by the vehicle speed arrival determination means, the detection It has a release vehicle speed determination means for determining whether or not the determined vehicle speed has become lower than the release vehicle speed, and after determining that the detected vehicle speed has reached the allowable maximum vehicle speed, it is determined that it has become lower than the release vehicle speed. Until
When the engine speed is determined to be equal to or higher than the determination speed, the operation stop signal is output, and when the engine speed is determined to be lower than the determination speed, output of the operation stop signal is stopped. A maximum vehicle speed control device is provided.

(Operation) The discriminating rotation speed is set to a new value each time the vehicle speed detection value reaches the maximum allowable vehicle speed only after the predetermined release vehicle speed exceeds. Therefore, the discriminating rotation speed set each time can accurately correspond to the maximum allowable vehicle speed even when the present invention is applied to the torque converter vehicle. For this reason, the engine is switched to inactive or active at the engine speed corresponding to the maximum allowable vehicle speed, and hunting is prevented.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

First, FIG. 2 shows a part of the maximum vehicle speed control device according to the device of the present invention, and reference numeral 1 in the drawing shows a four-cylinder gasoline engine mounted in the vehicle. A transmission 2 having a torque converter is attached to the engine 1, and a vehicle speed sensor (vehicle speed detecting means) 7 for detecting a vehicle speed is provided so as to face the outer periphery of a driven gear attached to an output shaft of the transmission. ing. The vehicle speed sensor 7 is electrically connected to the input side of the electronic control unit 6 and supplies the detected vehicle speed signal to the electronic control unit 6.

An encoder 1a is attached to the cam shaft of the engine 1, and an engine speed sensor (rotation speed detection means) 8 for detecting the engine speed Ne is attached to the outer periphery of the encoder 1a. This engine speed sensor 8
Is electrically connected to the input side of the electronic control unit 6 and supplies the detected engine speed signal to the electronic control unit 6.

The electronic control unit 6 has functions such as a judging means for judging whether or not the internal combustion engine should be inactivated, a vehicle speed arrival judging means, a release vehicle speed judging means, etc., and a central processing unit (CPU), ROM, RAM not shown. It has a built-in storage device such as the I / O interface. A combustion injection device for injecting fuel into the engine 1, an ignition device for igniting a mixture, and the like are connected to the output side of the electronic control unit 6 (neither is shown). These fuel injection device and ignition device function as engine inactivating means. The electronic control unit 6 executes a control program stored in the storage device to inject and supply these devices with a required amount of fuel according to the operating state of the engine 1, and ignite the air-fuel mixture at a required time. Output a control signal. Then, the electronic control unit 6 outputs a fuel cut signal or an ignition cut signal (hereinafter, referred to as "vehicle speed cut signal" or "operation stop signal") at the time of maximum vehicle speed control of the vehicle to operate the engine 1 as described later. The vehicle is stopped and the maximum vehicle speed is regulated to the maximum allowable vehicle speed.

The above-described storage device functions as a release vehicle speed storage unit that stores a release vehicle speed, which will be described later, and a determination rotation speed storage unit that stores the engine rotation speed when the vehicle speed reaches the maximum allowable vehicle speed as the determination rotation speed. .

Next, the maximum vehicle speed control procedure according to the present invention will be described with reference to FIG.

FIG. 1 is a program flow chart of a maximum vehicle speed control routine executed by the electronic control unit 6. The electronic control unit 6 first detects the vehicle speed by the vehicle speed sensor 7 (step 10). Then, the detected vehicle speed is compared with a predetermined release speed (for example, 175 km / h) to determine whether the vehicle speed is equal to or lower than the predetermined release speed (step 12). If the determination result is affirmative (Yes) and the vehicle speed is less than or equal to the predetermined release speed, the process proceeds to step 13, the flag FSTUDY value described later is reset to 0, the aforementioned vehicle speed cut signal is not output, and normal engine operation is performed. Control is executed (step 22). That is, when the vehicle speed is equal to or lower than the predetermined release speed, the normal engine operation control is unconditionally executed without performing the maximum vehicle speed control determination as described later.

When the determination result of step 12 is negative (No), that is, when the vehicle speed is equal to or higher than the predetermined release speed (175 km / h),
Proceeding to step 14, the engine speed Ne is detected by the engine speed sensor 8 and stored in the aforementioned storage device.

Next, the electronic control unit 6 sets the engine speed N corresponding to the predetermined maximum allowable vehicle speed (for example, 180 km / h).
e, that is, the following steps 16 to 19 are executed to store the discriminating rotational speed NECUT. That is, in step 16, it is determined whether or not the vehicle speed is equal to or lower than the predetermined allowable maximum vehicle speed, and if it is equal to or lower than the predetermined allowable maximum vehicle speed, the process proceeds to the subsequent step 20 without doing anything, and if it is equal to or higher than the predetermined allowable maximum vehicle speed, step 17 At, it is determined whether or not the flag FSTUDY value is equal to 1. When the vehicle speed exceeds the predetermined maximum allowable vehicle speed for the first time and step 17 is executed, the flag FSTUDY value is not yet set to the value 1, and in this case, the process proceeds to step 18 and the engine detected in step 14 The number of revolutions Ne is stored as the discriminating number of revolutions NECUT, and this value is stored in the flag FSTUDY (step 19). Once the discriminating rotation speed NECUT is set and the flag FSTUDY value is also set to the value 1, the discrimination result in step 17 becomes affirmative thereafter, and in this case, steps 18 and 19
And skip to step 20 above. As described above, the discriminating rotation speed NECUT is the maximum allowable vehicle speed (18
It will be set to the engine speed Ne corresponding to 0 km / h). Further, when the vehicle speed becomes equal to or lower than the predetermined release vehicle speed (175 km / h), the flag FSTUDY is reset to 0 as described above. Therefore, the discriminating rotation speed NECUT is reached every time the vehicle speed reaches the maximum allowable vehicle speed after the vehicle speed exceeds the predetermined release vehicle speed. It will be learned and set to a new value. The discriminating rotational speed NECUT is stored with a preset predicted value as an initial value when the ignition key switch is turned on.

In step 20, the engine rotational speed Ne detected in step 14 is compared with the discriminating rotational speed NECUT set as described above to discriminate whether the engine rotational speed Ne is equal to or lower than the discriminating rotational speed NECUT. And the engine speed Ne is the determination speed
If it is NECUT or higher, the routine proceeds to step 24, where the electronic control unit 6 outputs a vehicle speed cut signal to deactivate the fuel injection device or the ignition device (engine deactivating means) to stop the operation of the engine 10, and the engine speed. If Ne is equal to or less than the discriminating rotation speed NECUT, step 22 is executed and a vehicle speed cut signal is not output, and normal engine operation control is performed.

The method of the present invention is particularly effective when applied to a torque converter vehicle, but can be applied to a so-called manual shift vehicle that is not equipped with a torque converter.

(Effects of the Invention) As described in detail above, according to the maximum vehicle speed control device of the present invention, the vehicle speed is detected, the rotation speed of the internal combustion engine is detected, and the release vehicle speed smaller than the maximum allowable vehicle speed is set and detected. It is determined that the vehicle speed has reached the maximum allowable vehicle speed, and the engine speed detected when it is determined that the maximum allowable vehicle speed has been reached is stored as a determination rotational speed, and the vehicle speed detected thereafter is smaller than the release vehicle speed. Until it is determined that the detected engine rotation speed is lower than the determination rotation speed, the internal combustion engine is operated, while when the engine rotation speed is determined to be equal to or higher than the determination rotation speed, Since the internal combustion engine is disabled, hunting of the vehicle speed and engine speed is suppressed, and the discriminating speed corresponding to the maximum allowable vehicle speed is learned. Since the value is constantly updated to the latest value, even if the maximum vehicle speed is controlled by the engine speed, there is an excellent effect that the risk of malfunction is reduced.

[Brief description of drawings]

FIG. 1 is a flowchart showing a control procedure executed by the maximum vehicle speed control device according to the present invention, FIG. 2 is a block diagram showing a part of the configuration of the maximum vehicle speed control device according to the present invention, and FIG. In order to explain the problem of the maximum vehicle speed control method,
3 is a timing chart showing changes in vehicle speed and engine speed over time. 1 ... Internal combustion engine, 1a ... Encoder, 2 ... Transmission equipped with torque converter, 6 ... Electronic control unit (ECU), 7 ... Vehicle speed sensor, 8 ... Engine speed sensor.

Claims (1)

(57) [Claims] 1. A vehicle speed detecting means for detecting a vehicle speed of a vehicle equipped with an internal combustion engine, and determining whether or not the internal combustion engine should be deactivated according to the detected vehicle speed, and deactivating the internal combustion engine. A maximum output for controlling the vehicle speed to be equal to or lower than the set maximum allowable speed, the determination means outputting an operation stop signal when necessary, and the engine inactivating means for stopping the operation of the internal combustion engine in response to the operation stop signal. In the vehicle speed control device, a release vehicle speed storage unit that stores in advance a release vehicle speed smaller than the maximum allowable vehicle speed, a rotation speed detection unit that detects the rotation speed of the internal combustion engine, and the detected vehicle speed has reached the maximum allowable vehicle speed. Vehicle speed arrival determination means for determining, and a determination that stores the engine speed detected when it is determined that the vehicle speed has reached the maximum allowable vehicle speed as a determination speed. A rotation speed storage means, and the determination means determines whether the detected vehicle speed is lower than the release vehicle speed after determining that the vehicle speed has reached the allowable maximum vehicle speed by the vehicle speed arrival determination means. It is determined that the engine rotation speed is equal to or higher than the determination rotation speed until it is determined that the detected vehicle speed has become lower than the release vehicle speed after determining that the detected vehicle speed has reached the maximum allowable vehicle speed. The maximum vehicle speed control device is characterized in that the operation stop signal is output when the engine speed is exceeded, and the output of the operation stop signal is stopped when the engine speed is determined to be lower than the determination speed.