JPH03186434A - Constant speed running device - Google Patents

Abstract

PURPOSE:To improve transient responsiveness by limiting acceleration, which is for calculating an advance timing car speed used for calculating a control amount of a control means for controlling a throttle valve opening, to a level within the first predetermined value, at the time of a fixed speed running mode, and to within the second predetermined value at the time of an acceleration mode. CONSTITUTION:A set switch 1 is turned on at the time of fixed speed running, and a car speed Vn, detected by a car speed sensor 3 at this time, is stored in a memory 4 as a target car speed Vm. An advance timing car speed Vsk is calculated in a control amount arithmetic part 5 by the detected car speed Vn, and a control amount is calculated from Vm-Tsk. This control amount is converted into a drive signal having a corresponding control duty in a duty converting part 6, and a fixed speed running condition is obtained by driving an actuator 7 to adjust an opening of a throttle valve 8. In the control amount arithmetic part 5, calculated acceleration DELTAVn is corrected so as to be generated within an acceleration limit alpha, set in accordance with a fixed running mode and an acceleration mode, in an acceleration arithmetic part 16 in a car speed arithmetic part 13.

Description

[Detailed Description of the Invention] Overview In a constant speed traveling device that controls the throttle valve opening degree by calculating a control amount based on an advance vehicle speed and a target vehicle speed, in a normal constant speed travel mode, the advance angle is The acceleration for calculating the vehicle speed is the first
The advance angle vehicle speed is calculated by limiting it to within a predetermined value of -. Also,
When the accelerator switch or resume switch is operated, etc., and the acceleration mode is entered, the acceleration is set to the first
The advanced vehicle speed is calculated by limiting the advance angle vehicle speed to within a second predetermined value that is larger than the predetermined value.

As a result, there is no control delay and smooth acceleration is possible when the acceleration mode is entered, without impairing the stability in the normal constant speed driving mode.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant speed traveling device that automatically controls a throttle valve opening so that a traveling vehicle speed reaches a target vehicle speed without operating an accelerator pedal.

A conventional constant speed traveling device is a device that automatically adjusts and controls the throttle valve opening so that the vehicle travels at a target vehicle speed desired by the driver. The throttle valve is driven and controlled by an actuator using, for example, intake negative pressure.

That is, the actuator includes a diaphragm and is interposed in a link mechanism between the accelerator pedal and the throttle valve. The diaphragm is connected to the link mechanism, and the intake negative pressure introduced into the diaphragm chamber is
Adjustment is controlled by duty control of the control valve, and thus the throttle valve opening degree is controlled.

Is the throttle valve opening control duty based on the difference between the target vehicle speed set by the driver and the advance vehicle speed calculated from the actual traveling vehicle speed and its acceleration? i4
The acceleration is limited to within a predetermined acceleration level (acceleration limit).

Problems to be Solved by the Invention In typical conventional technology, for example, it is necessary to prevent problems such as hunting from occurring due to the inflow of noise into the wheel speed pulse from the wheel speed sensor that detects the traveling vehicle speed.
The acceleration level is the same in the acceleration mode as in the constant speed driving mode, for example, 0,7 (km/h/5ec
) is set to a relatively small value.

Therefore, in acceleration modes that require acceleration changes at large acceleration levels, such as when updating the vehicle speed by operating the accelerator switch or returning the vehicle speed by operating the resume switch, the acceleration limit is smaller than the actual vehicle acceleration. , lead angle compensation is not effective enough and a delay occurs. Therefore, there is a problem that a sufficient sense of acceleration cannot be obtained and the transient response is poor.

An object of the present invention is to provide a constant speed driving device that can provide a sufficient feeling of acceleration in acceleration mode without impairing stability in constant speed driving mode, and has excellent transient response. be.

Means for Solving the Problems The present invention comprises a vehicle speed setting means for setting a target vehicle speed, a vehicle speed detection means for detecting the running vehicle speed, and calculating the acceleration of the vehicle with a predetermined acceleration level as the upper limit, and calculating the advance angle from the acceleration. An advance angle vehicle speed calculation means for calculating a vehicle speed; an acceleration selection means for setting an acceleration mode; a control amount calculation means for calculating a control amount corresponding to the difference between the target vehicle speed and the advance angle vehicle speed; to control the throttle valve opening (
setting means for setting the acceleration level to a first predetermined value when the constant speed driving mode is set, and setting the acceleration level to a second predetermined value greater than the first predetermined value when the acceleration mode is set; The present invention is a constant speed traveling device characterized by including an upper limit value correcting means for setting a value.

According to the present invention, the upper limit value correcting means changes the upper limit value of acceleration for calculating advance vehicle speed to a larger value in the acceleration mode than in the constant speed driving mode, so that a small acceleration is changed in the constant speed driving mode. It is possible to achieve stable control at a high acceleration level, and in acceleration mode, a sufficient sense of acceleration can be obtained at a high acceleration level.

Embodiment FIG. 1 is a functional block diagram for explaining the principle of an embodiment of the present invention. When the switch 1 to the switch 1 is operated, the switch 2 becomes conductive, and the running vehicle speed Vn detected by the vehicle speed sensor 3, which is a vehicle speed detecting means, is stored in the memory 4 as the target vehicle speed Vm.

The vehicle speed sensor 3 detects, for example, the wheel speed of four wheels.
The maximum wheel speed is detected as the vehicle speed. set switch 1
, switch 2, and memory 4 constitute vehicle speed setting means.

The traveling vehicle speed Vn is also given to a control amount calculation section 5, and the control amount calculation section 5 calculates an advance vehicle speed Vsk based on the traveling vehicle speed Vn as described later, and calculates the advance angle vehicle speed Vsk based on the traveling vehicle speed Vn. A control amount is calculated based on the difference between Vm and this advanced vehicle speed Vsk.

The control amount calculated in this way is converted into a drive signal having a corresponding control duty by the duty converting section 6, and is output to the actuator 7, which is a control means, and has a configuration using a diaphragm as described above, for example. The actuator 7 drives and controls the thrower 1 hell valve 8 so that the opening degree corresponds to the control duty, thereby achieving constant speed running behavior 11'.

Further, during vehicle speed updating when the accelerator switch IJ- is operated, the switch 2 is turned on and the target vehicle speed vrn is updated. In addition, when the vehicle speed is updated and when the vehicle speed is restored by operating the resume switch 12, the acceleration mode is
The control duty calculated by the duty converter 6 is increased, and the acceleration limit α, which will be described later, is switched. The accelerator switch 11i5 and the resume switch 12 (, 1) constitute acceleration selection means.

The control amount calculation unit 5 calculates the advance vehicle speed Vsk,
A vehicle speed calculating section 13 which is an advance vehicle speed calculation means, an acceleration limit setting section 14 in which an acceleration limit α is set and which is an upper limit correction means, and a vehicle speed calculating section 13 which is an advance vehicle speed calculation means, an acceleration limit setting section 14 which is an upper limit value correcting means, and the target vehicle speed V m and an advance vehicle speed Vsk.
and a subtraction unit 15 which is a control amount calculation means. The vehicle speed calculation section 13 includes an acceleration calculation section 16, a multiplication section 17, and an addition section 18.

The acceleration calculation unit 16 calculates the current traveling vehicle speed as Vn.

In this case, the traveling vehicle speed Vrl+-4 and the traveling vehicle speed Vn before the fourth cycle of the control amount calculation operation to be described later.

, that is, the acceleration ΔVn, and the calculation result is within the acceleration limit α, that is, ΔVn1≦a (km/h/see)
−<1) and output to the multiplier 17. The multiplier 17 multiplies the acceleration ΔVn by a predetermined constant Sk, and the adder 18 adds the multiplication result to the traveling vehicle speed Vn as shown in the second equation, thus making the advance vehicle speed Vsk Desired.

Vsk=Vn+Sk*(ΔVII) −(
2) FIG. 2 is a block diagram showing the configuration of a constant speed traveling device in which the present invention is implemented. The control amount of the thrower 1 and health 8 is determined by the processing circuit 21 realized by a microcomputer or the like.
A drive signal having a control duty corresponding to the result of the calculation is given to the actuator 7.

The processing circuit 21 is supplied with outputs from the set switch 1, the accelerator switch 11, the resume switch 12, and the vehicle speed sensor 3.

The actuator 7 is interposed in a link mechanism 23 that connects the accelerator pedal 22 and the throttle valve 8, and can control opening and closing of the throttle valve 8. By controlling the opening of the throttle valve 8, the flow rate of intake air passing through the intake pipe 24 changes, thereby changing the l·lux generated by the internal combustion engine 25, thereby making it possible to adjust the vehicle speed.

FIG. 3 is a flowchart for explaining the above-mentioned constant speed running control operation. In step S1, it is determined whether or not the set switch 1 is operated. If so, the set mode is set in step S2, and then the process moves to step S3. If the set switch 1 is not operated in step S1, It is determined in step S4 whether or not the accelerator switch 11 has been operated, and if so, the accelerator mode is set in step S5, and then
The process moves to step s3.

In step s3, the actual vehicle speed Vn is calculated by 31 based on the wheel speed pulse from the wheel speed sensor 3. In step S6, the actual vehicle speed Vn obtained in step s3 is changed to the target vehicle speed Vm.
It is stored in the memory 4 as .

Further, if the accelerator switch 11 is not operated in step s4, the process moves to step s7, where it is determined whether the resume switch 12 has been operated, and if so, the resume mode is set in step s8, and then step s9 If not, the process moves to step slo. In step slo, it is determined whether or not constant speed driving control is being performed. If not, that is, if the brake pedal is depressed and the vehicle is in a non-control state, the process returns to step s1, and if so, the process returns to step s1. Move to s9. In step S9, the actual vehicle speed Vn is determined as in step s3.

Step s6. From s9, the process moves to step sll, where the current vehicle speed V n calculated in step S3 or s is calculated.
+ and the vehicle speed Vn1-1 at the time of the previous calculation operation by four calculation cycles of the calculation unit 1Ya shown in FIG. 3, the acceleration ΔVn is calculated.

In step 312, it is determined whether the current mode is acceleration mode, accelerator mode or resume mode, and if so, step s13 determines that the acceleration limit α is larger than the actually occurring acceleration, e.g.
, 5 (kv/h/5ee), and when this is not the case, that is, during normal constant speed driving mode, in step s14, the acceleration limits 1 to α are set to, for example, 0, 7 (kv/h/5ee). km/h/5ec), which is set to a relatively small value.

Said step s13. From s14, the process moves to step S15, where the advanced vehicle speed Vsk is calculated based on the second equation. In step s16, the difference between the target vehicle speed Vm set in step s6 and the advance vehicle speed Vsk determined in step s15 is calculated. In step s17,
The control duty of the actuator tough is determined from the calculation result in step s16, and the opening degree of the throttle valve 13 is controlled in accordance with the calculation result in step s18.

In this way, in the constant speed traveling device according to the present invention, the acceleration limit α is switched between the constant speed traveling mode and the acceleration mode, so that in the constant speed traveling mode where the acceleration limit α is small, the noise to the wheel speed pulse is reduced. Stable control can be performed without problems such as hunting due to contamination, and in acceleration mode with a large acceleration limit α, the acceleration limit α is larger than the actual acceleration, so the lead angle compensation is sufficient. It is possible to perform smooth acceleration without control delay.

In the above-described embodiment, the actuator 7 is a duty-controlled actuator using intake negative pressure, but in other embodiments of the present invention, it may be a motor-type actuator, for example.

Effects of the Invention As described above, according to the present invention, the acceleration for calculating the advance angle vehicle speed used for calculating the control amount of the control means for controlling the throttle valve opening is within the first predetermined value in the constant speed driving mode. and within the second predetermined value that is larger than the first predetermined value in the acceleration mode, stable control can be achieved without problems such as hunting in the constant speed driving mode. In addition, in the acceleration mode, a sufficient feeling of acceleration can be obtained without causing breathiness or the like, and transient response can be improved.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram for explaining the present invention in detail, FIG. 2 is a block diagram showing the configuration of a constant speed traveling device in which the present invention is implemented, and FIG. 3 is for explaining the constant speed traveling operation. This is a flowchart. 1...set switch, 2...switch, 3...
Vehicle speed sensor, 4. Memory, 5. Controlled amount calculation unit, 6.
...Duty conversion unit, 7...Actuator, 8.
...Throttle valve, 11...Accelerator switch, 12
...Resume switch, 13...Vehicle speed calculation section, 1
4... Acceleration limit setting section, 16... Acceleration calculation section, 21... Processing circuit, 22... Accelerator pedal,
25... Internal combustion engine

Claims (1)

[Claims] Vehicle speed setting means for setting a target vehicle speed, vehicle speed detection means for detecting the running vehicle speed, and a progressor for calculating the acceleration of the vehicle with a predetermined acceleration level as the upper limit and calculating the advance angle vehicle speed from the acceleration. angular vehicle speed calculation means; acceleration selection means for setting an acceleration mode; control amount calculation means for calculating a control amount according to the difference between the target vehicle speed and the advance angle vehicle speed; and a throttle valve opening according to the control amount. a control means for controlling the acceleration level; when set to constant speed driving mode, the acceleration level is set to a first predetermined value, and when set to the acceleration mode, the acceleration level is greater than the first predetermined value; A constant speed traveling device comprising: an upper limit value correcting means that sets the upper limit value to a second predetermined value.