JPH0572303B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a constant speed traveling device for an automobile, in particular,
A vehicle speed detection means for detecting the vehicle speed, a vehicle speed setting means for setting the vehicle speed during constant speed driving, an actuator for adjusting the throttle opening of the engine so that the detected vehicle speed is maintained at the set vehicle speed, and an output from the vehicle speed setting means. The present invention relates to a constant speed traveling device for an automobile, which is equipped with a control means for driving an actuator in response to a driving force.

(Prior Art) Conventionally, in the case of constant speed traveling devices of this type of automobile, a set vehicle speed and a detected vehicle speed are compared, and an actuator is driven to adjust the opening degree of the throttle in response to the deviation. The vehicle was controlled to run at a constant speed.

However, if the constant-speed running setting operation is performed in conditions where the engine load increases and the vehicle speed tends to decrease, such as when going up a hill, the control amount at the initial activation of the actuator will be insufficient due to a delay in control response, and the vehicle speed will decrease. A decline was inevitable.

For example, when a car drives on a slope such as an uphill road, the load on the engine increases. The appropriate engine output cannot be obtained immediately. As a result, there was a problem that the actual vehicle speed was lower than the set vehicle speed.

Therefore, there is a method that can maintain constant speed even on an uphill road by detecting that the vehicle is traveling on an uphill road and automatically downshifting the transmission to reduce the engine load. (See, for example, Japanese Patent Application Laid-Open No. 121713/1983).

However, the above conventional means is a solution for dealing with an increase in load after starting constant speed driving, that is, during constant speed driving, but does not improve the control response at the time of setting constant speed driving. Ta.

(Problems to be Solved by the Invention) The present invention has been made in view of the above-mentioned circumstances, and its purpose is to maintain the vehicle speed from the start of constant speed travel (at the time of set) even when traveling on a slope. It is an object of the present invention to provide a constant speed traveling device for a motor vehicle equipped with a control means with little fluctuation.

(Means for Solving the Problems) In order to achieve the above object, a constant speed traveling device for an automobile according to the present invention includes a slope detecting means for detecting the slope in the longitudinal direction of the vehicle body, and a slope detection means for detecting the slope in the longitudinal direction of the vehicle body, and The present invention is characterized in that it includes an operation time setting means for variably setting the initial operation time of the actuator in response to the output from the inclination detection means, and its functions and effects are as follows.

(Function) In other words, the set vehicle speed for constant-speed driving is set so that the initial activation time of the actuator is longer on uphill roads, and conversely so that the initial activation time is shorter than usual on downhill roads. The initial actuation time of the actuator is controlled to be automatically corrected in accordance with the degree of inclination of the vehicle body when the vehicle is tilted.

(Effects of the Invention) Because of the above characteristics, the following excellent effects have been achieved.

In other words, by variably setting the initial actuation time of the actuator in accordance with the degree of inclination of the vehicle body,
This has made it possible to prevent actual vehicle speed fluctuations due to engine load fluctuations and control response delays when the vehicle is set to start constant speed travel while traveling on a slope.

In addition, on a downhill road, the initial activation time can be controlled to be shorter than usual, and in that case, the control that causes the actuator to operate unnecessarily is suppressed, thereby reducing unnecessary acceleration on a downhill road. It also has the effect of preventing it.

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

As shown in FIG. 4, a power source 4 is connected to the control means 1 of the constant speed traveling device via a key switch 2 and a main switch 3. Furthermore, the control means 1 includes a set switch 5 which constitutes a vehicle speed setting means and instructs the start of constant speed driving and the setting of the vehicle speed during constant speed driving, and the set switch 5 turns on the set vehicle speed set by the set switch 5. The coast switch 6 instructs the vehicle to decelerate while the vehicle is turned off and set the vehicle speed at the time of turning OFF as the new set vehicle speed, which is automatically canceled if constant speed driving is canceled by an operation other than the operation of the main switch 3. A lysium switch 7 instructs to resume constant speed driving at the previously set vehicle speed, a vehicle speed sensor 8 that constitutes a vehicle speed detection means and detects the actual vehicle speed, a brake switch 9 that turns on when the brake is pressed while driving, and a clutch that is turned off. When operated
Signals are inputted from a clutch switch 10 which is turned on, and a slope detection sensor 11 as a slope detection means for detecting the slope θ in the longitudinal direction of the vehicle body in the latter stage configuration.

This constant speed traveling device basically sets the vehicle speed at the time when the set switch 5 is turned on as a set vehicle speed _V0 , and combines this set vehicle speed _V0 with the vehicle speed sensor 8.
The actuator 13 that adjusts the opening degree of the throttle valve 12 is driven based on the comparison result with the vehicle speed V detected by the brake switch ₉ or the clutch switch 10. When turned on, the vehicle is controlled to stop constant speed driving.

The initial operating time t of the actuator 13 when the set switch 5 is pressed is variably set based on the slope θ detected by the slope detection sensor 11, thereby reducing the delay in control response when the vehicle is set to constant speed running. It's like this.

The control means for controlling the actuator and the operation time setting means for variably setting the initial operation time t of the actuator 13 based on the detected inclination angle θ will be described below.

As shown in Figure 1, the control means basically consists of:
The set vehicle speed V ₀ as a control target during constant speed driving is set by storing the detected vehicle speed V at the time when the set switch 5 is pressed in the storage means 14 such as a non-volatile memory, and the vehicle speed sensor 8 A comparator 15 compares and calculates the detected vehicle speed V,
The actuator 13 is configured to be driven in pulses by the output _P1 .

A one-shot multivibrator 16 is provided as an operation time setting means whose output pulse width changes in accordance with the detected slope θ at the time when the set switch 5 is pressed, and the output P ₂ of this one-shot multivibrator 16 is The output P ₁ of the comparator 15 is connected to the actuator 13 via the OR gate 17, and the initial operating time t of the drive pulse P ₃ of the actuator 13 is determined as shown in FIG. The configuration is such that the larger the initial operating time t becomes, the longer the initial operating time t becomes.

The vehicle speed sensor 8 generally uses a reed switch or the like that turns on/off depending on the rotation speed of a cable that transmits the rotation speed from the transmission to the speedometer, and its detection signal is sent to the F/V converter 18.
The sensor is configured to convert the detected frequency into a voltage using the .

The inclination detection sensor 11 is constructed by, for example, a weight hanging freely rotatably in the longitudinal direction of the vehicle body, and detecting the rotation angle of the weight as a change in the output resistance value of the potentiometer R. be.

Moreover, the one-shot multivibrator 1
6, as shown in FIG.
The slope detection sensor 1 is connected to a capacitor C and a resistor R that determine the width of _P2 , that is, a time constant corresponding to the initial operating time t of the actuator 13.
1 potentiometer is used, and the time constant t of the output pulse becomes longer as the inclination becomes larger, corresponding to the degree of inclination of the vehicle body.

Next, the actuator 13 will be briefly explained.

As shown in FIG. 5, the throttle valve 12 is connected via a driving force transmission member 21 such as a wire to a diaphragm 20 having an operating chamber, one side of which is open to the atmosphere and the other side communicated with the intake manifold 19. The driving time of the three solenoids 22a, 22b, and 22c is controlled so that the detected vehicle speed V is maintained at the set vehicle speed _V0 by using the differential pressure between the intake manifold 19 and the engine intake negative pressure of the intake manifold 19. The opening degree of the throttle valve 12 is automatically adjusted by adjusting the amount of movement of the throttle valve 20. Note that the first solenoid 22a of the three solenoids 22a, 22b, and 22c controls communication and isolation between the working chamber and the intake manifold 19, and the other two solenoids 22b and 22c control communication between the atmosphere and the working chamber. Only one of the two solenoids 22b and 22c, 22b, is shown in FIG. 5.

FIG. 6 shows another embodiment of the inclination detection means, in which the inclination θ detected by the inclination detection sensor 11 may have an error due to the influence of acceleration due to its configuration. This has been automatically corrected accordingly.

That is, an inclination angle detection means 11' that converts a change in the resistance value of the potentiometer R into a change in voltage, etc.;
Acceleration detection means 23 detects a change in vehicle speed V detected by the vehicle speed sensor 8, that is, acceleration g, and converts it into a voltage change etc. in the same manner as described above, and slope correction means 24 subtracts the detected acceleration g from the detected slope θ. This constitutes an inclination detecting means, and is controlled to adjust the initial operating time t of the actuator 13 based on the output of the correcting means 24, that is, the corrected inclination θ'.

In this way, by automatically correcting the detected inclination θ using the acceleration g, there is an effect that detection errors caused by changes in vehicle speed can be reduced.

Moreover, the one-shot multivibrator 1
6, the output pulse width t is directly determined by the resistance change of the potentiometer R of the inclination detection sensor 11 shown in FIG. 3, or the detected acceleration shown in FIG. In addition to the configuration in which the output pulse width t is determined in accordance with the slope θ' corrected by g, there is also a configuration in which the output pulse width t using a timer or counter changes in response to the detected slope θ. Various changes can be made, such as, and furthermore, it may be configured using the calculation function of a microcomputer.

In addition, the inclination detection sensor 11 may be configured in other formats, such as a configuration in which the inclination θ is not detected analogously using the potentiometer R, but digitally using an encoder or the like. You may also use one.

[Brief explanation of drawings]

The drawings show an embodiment of the constant speed traveling device for an automobile according to the present invention, FIG. 1 is a block diagram showing the main part configuration of the constant speed traveling device, and FIG. 2 shows the relationship between the detected slope and the initial actuation time of the actuator. 3 is a circuit diagram showing the configuration of the one-shot multivibrator, FIG. 4 is a block diagram showing the overall configuration of the constant speed traveling device, FIG. 5 is a side sectional view showing the configuration of the actuator, and FIG. 6 is a block diagram showing the structure of another embodiment of the inclination detecting means. 8... Vehicle speed sensor, 11... Tilt detection sensor, R... Potentiometer, V... Detected vehicle speed,
V ₀ ... Set vehicle speed, θ ... Detected slope, P ₃ ... Actuator drive signal, t ... Initial operation time.

Claims (1)

[Claims] 1 Vehicle speed detection means for detecting vehicle speed, vehicle speed setting means for setting the vehicle speed during constant speed driving, actuator for adjusting the throttle opening of the engine so that the detected vehicle speed is maintained at the set vehicle speed, and the vehicle speed setting means. A constant speed traveling device for an automobile, comprising a control means for driving an actuator in response to an output, the slope detecting means detecting the slope in the longitudinal direction of the vehicle body, and the slope detecting means detecting the slope when setting the vehicle speed for constant speed driving. 1. An operating time setting means for variably setting an initial operating time of an actuator in accordance with the output of the vehicle.