JPH0584253B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] <Industrial Field of Application> The present invention is capable of constant speed driving to maintain the actual vehicle speed at the target vehicle speed, and also has the ability to control the signal from the resume switch after cancellation. The present invention relates to a control system for a constant-speed traveling device for a vehicle, which returns the actual vehicle speed to the target vehicle speed based on an input to perform constant-speed traveling.

<Prior Art> In general, a constant speed vehicle running system stores the current vehicle speed as a target vehicle speed in response to a signal input from a set switch, and thereafter maintains the target vehicle speed to drive at a constant speed. Furthermore, even if the constant speed driving state is once canceled by operating the brake, for example, constant speed driving can be resumed at the target vehicle speed before cancellation by operating the resume switch.

When performing this cancel processing, it is necessary to free the actuator wire connected to the throttle valve so as not to interfere with opening and closing of the throttle valve by accelerator operation. Therefore, at the start of resume, initialization processing is performed on the actuator in order to smoothly switch from the accelerator operation state to actuator control.

Regarding this initialization process at the time of resume, for example, there is a method that uses the initialization time of the target vehicle speed, but if the actual vehicle speed at the start of resume is considerably lower than the target vehicle speed, the opening degree corresponding to the actual vehicle speed may be used. Since the throttle valve is opened wide and a large initial acceleration is generated, an overshoot phenomenon occurs and the vehicle speed converges to the target vehicle speed. In addition, there is a control system that uses the initialization time based on the actual vehicle speed, which changes length depending on the actual vehicle speed, as the initialization time at the start of resume. If the vehicle speed is considerably low, the initialization time is also short and the opening of the throttle valve upon initialization is small, resulting in an undershoot phenomenon caused by a small initial acceleration and convergence to the target vehicle speed.

In this way, in any case, if the actual vehicle speed at the start of resume is much lower than the target vehicle speed, overshoot or undershoot will occur, so the convergence until the target vehicle speed returns is
This is worse than when the vehicle speed is close to the target vehicle speed, and the convergence will vary depending on the actual vehicle speed at the start of resume, which may cause an uncomfortable feeling during operation.

<Problems to be Solved by the Invention> In view of the problems of the prior art, the main purpose of the present invention is to return the actual vehicle speed to the target vehicle speed before the cancellation by inputting a resume signal after canceling constant speed driving. It is an object of the present invention to provide a control system for a constant speed traveling device for a vehicle that can eliminate the sense of discomfort caused by a difference in convergence due to a difference in actual vehicle speed at the start of resume.

[Structure of the Invention] <Means for Solving the Problems> According to the present invention, the present invention provides a control means that performs calculation control to maintain the actual vehicle speed at the target vehicle speed and generates an acceleration/deceleration control signal; and a drive circuit for driving an actuator that performs a vehicle speed control operation based on the control signal, and the control means stores a target vehicle speed by inputting a set signal, and
In a control system for a constant speed traveling device for a vehicle, the control means controls the vehicle to travel at a constant speed at a target vehicle speed before cancellation by inputting a resume signal after canceling constant speed traveling, wherein the control means inputs a resume signal after canceling constant speed traveling. When inputting a signal, if there is a vehicle speed difference between the target vehicle speed and the actual vehicle speed, the initialization time is calculated by adding additional time to the initialization time based on the actual vehicle speed, which varies depending on the height of the actual vehicle speed. An acceleration control signal is generated to the actuator, and the additional time is set to a constant value when the vehicle speed difference is large, and is increased or decreased according to an increase or decrease in the vehicle speed difference when the vehicle speed difference is small. This is achieved by providing a control system for a constant speed vehicle for vehicles that achieves this goal.

<Operation> By doing this, when the difference between the target vehicle speed and the actual vehicle speed is relatively large at the time of starting resume, the initialization time is set by adding a certain time to the initialization time based on the actual vehicle speed at that time. Since the acceleration control is performed based on the actual vehicle speed, the target vehicle speed can be reached with faster acceleration than when acceleration is performed using an initialization time based on the actual vehicle speed. In addition, when the difference between the target vehicle speed and the actual vehicle speed is relatively small, the additional time to be added is set to an initialization time that is increased or decreased according to the increase or decrease in the vehicle speed difference. Since acceleration control is performed using the initialization time, it is possible to reach the target vehicle speed without overshooting the vehicle speed.

<Embodiments> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a circuit diagram showing a general configuration of a constant speed traveling device for an automobile based on the present invention. A control section 1 as a control means having a CPU for arithmetic processing and an input/output interface for running at a constant speed is connected via a main switch 2 to a battery (not shown) as a power source. In addition, the control unit 1 includes
For example, a pulse signal from a vehicle speed sensor 3 is input as a vehicle speed signal, and a set switch 4 is operated to set the actual vehicle speed as the target vehicle speed during constant speed driving, and to set the target vehicle speed again after canceling constant speed driving. A resume switch 5, which is operated when returning the main switch 2, is connected in parallel with the main switch 2.

The actuator 6 in this embodiment includes a motor 7 as a driving source, an actuating member 10 connected to the throttle valve 8 via an actuator wire 9, and the motor 7 and the actuating member 10. A magnetic clutch 11 is provided for selective connection. Therefore, when the magnetic clutch 11 is in the connected state, the throttle valve 8 is interlocked with the rotation of the motor 7.

In the drive circuit 12 for driving the actuator 6 by the signal from the control section 1 described above, four transistors Q1 are used as shown in the figure.
A transistor bridge circuit of a known type consisting of Q4 constitutes a forward/reverse drive circuit for the motor 7, and is also provided with a transistor Q5 for controlling the excitation coil 13 of the magnetic clutch 11 on and off.

In the bridge circuit described above, the emitters of the transistors Q1 and Q2 which are parallel to each other are connected to the power supply terminal V, and the collectors of the transistors Q1 and Q2 are connected to the collectors of the transistors Q1 and Q2, respectively.
Each of the emitters No. 3 and Q4 is grounded via the control section 1. A normally closed limit switch 14,
15, both terminals of the motor 7 are connected. Therefore, by supplying an ON signal from the control unit 1 to the transistors Q1 and Q4, the motor 7 rotates in a direction that drives the actuating member 10 to the acceleration side, which is the fully closed side of the throttle valve 8, or the transistor Q2 By supplying an ON signal to Q3 and Q3, the motor 7 rotates in a direction that drives the actuating member 10 to the deceleration side.

Note that when the actuating member 10 reaches the acceleration side operating limit, the limit switch 14 is opened and the actuating member 1
Each of the limit switches 14 and 15 is set so that the limit switch 15 is opened when 0 reaches the deceleration side operating limit. Further, the limit switch 14 is provided with a diode D1 which is oriented to flow a deceleration side drive current to the motor 7.
Diodes D2 are connected in parallel to each of the diodes D2 in the direction in which the acceleration side drive current flows through the motor 7.
By doing so, over-rotation of the motor 7 can be suitably prevented.

Next, the operation procedure according to this embodiment will be described below.

By turning on the main switch 2, voltage is supplied to the control section 1, and the constant speed traveling device becomes ready. When it is desired to drive the vehicle at a constant speed from this state, the throttle valve 8 is opened and closed using an accelerator (not shown), and the set switch 4 is turned on at the desired actual vehicle speed. The control unit 1 stores the actual vehicle speed at the time of setting as the target vehicle speed, and the actuator 6 is configured to maintain the actual vehicle speed at the target vehicle speed thereafter.
By driving the throttle valve 8, the opening and closing of the throttle valve 8 can be controlled to perform constant speed driving.

Incidentally, when the vehicle is not running at a constant speed, the magnetic clutch 11 is disengaged to free the actuating member 10 and the actuator wire 9 so as not to interfere with accelerator operation. Therefore,
At the start of constant speed travel, the operating member 10 is initially driven by an amount corresponding to the opening degree of the throttle valve 8 at that time, thereby making it possible to smoothly switch to the constant speed travel state. The initialization process at this time of setting involves initially driving the motor 7 with an initialization time based on the actual vehicle speed, which varies in length and shortness in proportion to the actual vehicle speed, as shown by the dashed line in FIG. This ensures that the opening amount of the throttle valve 8 matches the actual vehicle speed at the time of setting.

Next, when a brake operation is performed to decelerate while driving at a constant speed, the constant speed driving state is temporarily canceled, but the target vehicle speed before cancellation is stored until the vehicle speed drops below a predetermined speed, for example. By turning on the resume switch 5, the vehicle can return to the constant speed running state again. At this time, an initialization signal is supplied from the control section 1 to the motor 7 in the same manner as at the time of setting.

Regarding the initialization time at the start of this resume, if the actual vehicle speed (V1) in the figure becomes lower than the target vehicle speed (Vs) due to brake operation as described above, the initialization time (based on the actual vehicle speed) The initialization time (T1 + Tα) is obtained by adding the additional time (Tα) to T1).
Note that this additional time (Tα) is the initialization time in which the throttle valve 8 is opened to an extra degree so that the vehicle speed becomes the actual vehicle speed at the start of resume plus 1 to 2 km/h, for example. It is enough to just add it like this. Therefore, as in the case of using the initialization time (Ts) based on the target vehicle speed, the opening degree of the throttle valve 8 becomes too large relative to the actual vehicle speed (V1), causing a large initial acceleration and overshooting. I started to feel like a yuto,
Initialization time (T1) based on actual vehicle speed
It is possible to eliminate the unnatural feeling of undershooting caused by a small initial acceleration due to the opening degree of the throttle valve 8 that is too small relative to the target vehicle speed (Vs), as in the case of using the vehicle speed (Vs).

In addition, in this embodiment, the initialization time at the start of resume, which is obtained by adding the additional time (Tα) to the initialization time based on the actual vehicle speed, is the initialization time (Ts) based on the target vehicle speed as shown in the figure. When the time exceeds the target vehicle speed as shown by the broken line, it becomes the same as the initialization time (Ts) based on the target vehicle speed as shown by the solid line in the figure. Therefore, since the throttle valve 8 is not opened too much beyond the opening degree corresponding to the target vehicle speed (Vs), for example, when the actual vehicle speed increases due to long downhill driving and the cancel processing is performed in the same manner as described above, the throttle valve 8 is reset again. When the resume switch 5 is turned on to return to high-speed driving, the vehicle speed can be smoothly converged to the target vehicle speed with appropriate engine braking.

Furthermore, as shown in Figure 2, the target vehicle speed (Vs)
A vehicle speed (Vp) higher than a predetermined value is set as a switching point between initialization and non-initialization, and when the actual vehicle speed at the start of resume is equal to or higher than this switching point, the initialization time is set to 0. By doing this, when the actual vehicle speed (V2) at the start of resume is equal to or higher than the vehicle speed (Vp) at the switching point, the throttle valve 8 is in the fully closed state at the beginning, and strong engine braking is applied. can be used to quickly decelerate.

After performing the initialization process described above,
Normal constant speed driving control is performed to maintain the actual vehicle speed at the target vehicle speed.

[Effects of the Invention] As described above, according to the present invention, when the difference between the target vehicle speed and the actual vehicle speed is relatively large at the time of starting resume, the initialization is performed by adding a certain time to the initialization time based on the actual vehicle speed. By performing acceleration control over time, the target vehicle speed can be reached without undershooting by quickly accelerating with a large initial acceleration due to an initialization time longer than the initialization time based on the actual vehicle speed. In addition, when the difference between the target vehicle speed and the actual vehicle speed is relatively small, the additional time to be added is increased or decreased according to the increase or decrease in the vehicle speed difference.
Therefore, suitable acceleration control that can prevent vehicle speed overshoot can be performed without unnecessarily increasing the initialization time. In this way, by performing acceleration control with an appropriate initialization time depending on the size of the vehicle speed difference at the start of resume, it is possible to smoothly converge to the target vehicle speed and perform constant speed driving, which is extremely effective. It's large.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a general configuration of a constant speed traveling device for an automobile based on the present invention. Figure 2 shows
FIG. 3 is a diagram showing initialization times depending on differences in actual vehicle speed at the time of starting resume according to the present invention. 1...Control unit, 2...Main switch, 3...
Vehicle speed sensor, 4...Set switch, 5...Resume switch, 6...Actuator, 7...
Motor, 8... Throttle valve, 9... Actuator wire, 10... Operating member, 11... Magnetic clutch, 12... Drive circuit, 13...
Excitation coil, 14, 15...limit switch.

Claims (1)

[Scope of Claims] 1. A control means that performs arithmetic control to maintain the actual vehicle speed at a target vehicle speed and generates an acceleration/deceleration control signal, and a drive circuit that drives an actuator that performs a vehicle speed control operation based on the control signal. , wherein the control means stores a target vehicle speed by inputting a set signal, and controls the vehicle to travel at a constant speed at the target vehicle speed before cancellation by inputting a resume signal after canceling constant speed traveling. In the control system for a constant speed traveling device for use in a vehicle, the control means controls the actual vehicle speed to change length depending on the height of the actual vehicle speed if there is a vehicle speed difference between the target vehicle speed and the actual vehicle speed at the time of inputting the resume signal. generating an acceleration control signal to the actuator with an initialization time obtained by adding an additional time to an initialization time based on the vehicle speed, and setting the additional time to a constant value when the vehicle speed difference is large;
A control system for a constant speed traveling device for a vehicle, characterized in that when the vehicle speed difference is small, the control system increases or decreases according to an increase or decrease in the vehicle speed difference.