JPH05262165A - Constant speed traveling controller for automobile - Google Patents

Abstract

PURPOSE:To improve the riding comfortableness by installing a selecting device which gives the throttle valve opening/closing operation quantity supplied from a throttle valve opening/closing operation quantity estimating device after the lapse of a specified time in from the start of the constant speed traveling, as throttle valve opening/closing signal into a throttle valve opening/closing device. CONSTITUTION:A selecting device 29 which gives the throttle valve opening/ closing operation quantity supplied from a throttle valve opening/closing operation quantity determining device 24 as throttle valve opening/closing signal to a throttle valve opening/closing device 14 for a specified time on the start of the constant speed traveling and gives the throttle valve opening/closing operation quantity supplied from a throttle valve opening/ closing operation quantity estimating device 28 as throttle valve opening/closing signal into the throttle valve opening/closing device 14 after the lapse of a specified period on the start of the constant speed traveling is installed. Accordingly, in the constant speed traveling, the change of the car speed from the start is made smooth, and the traveling of the vehicle is stabilized.

Description

Detailed Description of the Invention

[0001]

[Object of the Invention]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle running speed set while controlling a throttle valve opening according to a set vehicle speed given by a vehicle speed setting device and a detected vehicle speed given by a vehicle speed detection device. The present invention relates to a constant speed running control system for a vehicle, which is controlled so as to maintain the above, particularly, a first set which is established between a fuzzy set regarding a set vehicle speed, a fuzzy set regarding a negative pressure of an intake manifold, and a fuzzy set regarding a throttle valve opening correction amount. The throttle valve opening is determined by correcting the throttle valve basic amount calculated from the set vehicle speed by the throttle valve opening correction amount obtained by fuzzy inference according to the set vehicle speed and the intake manifold negative pressure based on the fuzzy rule of The first throttle valve opening / closing operation amount calculated by comparing with the throttle valve opening detection value At the start (that is, when the vehicle speed is set by the vehicle speed setting device), the throttle valve opening / closing signal is given to the throttle valve opening / closing device for a predetermined period to start the constant speed running, and then the fuzzy set regarding the vehicle speed deviation and the fuzzy regarding the vehicle speed change. The second throttle valve opening / closing operation amount obtained by fuzzy inference according to the vehicle speed deviation and the vehicle speed change based on the second fuzzy rule established between the set and the fuzzy set regarding the throttle valve opening / closing operation amount is a throttle valve opening / closing signal. The present invention relates to a constant speed running control device for an automobile, which is provided to a throttle valve opening / closing device to continue constant speed running.

[0003]

2. Description of the Related Art Conventionally, as a constant speed running control device for an automobile of this type, a driver operates a constant speed running start switch when an actual vehicle speed detected by a vehicle speed detection device (that is, a detected vehicle speed) reaches a desired value. The vehicle speed setting device is operated to maintain the vehicle speed, and the throttle valve is operated according to the difference between the vehicle speed held by the vehicle speed setting device (that is, the set vehicle speed) and the actual vehicle speed detected by the vehicle speed detection device (that is, the detected vehicle speed). Open / close operation amount
(That is, the throttle valve opening change amount; the same applies below)
There has been proposed a constant speed running control device for an automobile, in which the throttle valve opening / closing signal is determined and given to the throttle valve opening / closing device (see Japanese Patent Laid-Open No. 3-82635).

[0004]

[Problems to be Solved] However, in the conventional constant-speed running control device for an automobile, the difference between the set vehicle speed given by the vehicle speed setting device and the detected vehicle speed given by the vehicle speed detection device is directly corresponded. Since the throttle valve opening / closing operation amount was determined, (i) there is a drawback that the throttle valve is opened / closed in a manner that immediately responds to changes in the detected vehicle speed and is directly proportional to the amount of change in the detected vehicle speed. There was a drawback that the change became excessively sharp and the riding comfort deteriorated.

Therefore, in order to eliminate these drawbacks, the first aspect of the present invention is established between a fuzzy set regarding a set vehicle speed, a fuzzy set regarding an intake manifold negative pressure, and a fuzzy set regarding a throttle valve opening correction amount. The throttle valve opening is determined by correcting the throttle valve basic amount calculated from the set vehicle speed by the throttle valve opening correction amount obtained by fuzzy inference according to the set vehicle speed and the intake manifold negative pressure based on the fuzzy rule. The throttle valve opening / closing device is used as the throttle valve opening / closing signal only for a predetermined period when the first throttle valve opening / closing operation amount obtained by comparison with the valve opening detection value is started at the start of constant speed traveling (that is, when the vehicle speed is set by the vehicle speed setting device). To start constant speed running,
Then, the fuzzy reasoning is obtained according to the vehicle speed deviation and the vehicle speed change based on the second fuzzy rule established between the fuzzy set relating to the vehicle speed deviation, the fuzzy set relating to the vehicle speed change, and the fuzzy set relating to the throttle valve opening / closing operation amount. The second object is to provide a constant speed running control device for an automobile, which supplies a second throttle valve opening / closing operation amount as a throttle valve opening / closing signal to the throttle valve opening / closing device to continue constant speed running.

[0006]

[Constitution of the invention]

[0007]

[Means for Solving the Problems] The means for solving the problems provided by the present invention is to adjust the throttle valve opening in accordance with the set vehicle speed given by the vehicle speed setting device and the detected vehicle speed given by the vehicle speed detecting device. In a constant-speed traveling control device for a vehicle, which controls the traveling speed of the vehicle while maintaining the set speed, (a) the input end is connected to the output end of the vehicle speed setting device, and the A throttle valve opening basic amount calculation device (22A) for calculating the throttle valve opening basic amount based on the set vehicle speed, and (b) the first input end is connected to the output end of the vehicle speed setting device and The second input end is connected to the output end of the intake manifold negative pressure detection device, and a fuzzy set relating to the set vehicle speed, a fuzzy set relating to the intake manifold negative pressure, and a fuzzy set relating to the throttle valve opening correction amount. Based on the first fuzzy rule that is established between the throttle valve opening correction amount inferring device and the intake manifold negative pressure according to the set vehicle speed and the intake manifold negative pressure. ), And (c) the first input end is connected to the output end of the throttle valve opening basic amount calculation device (22A), and the second input
The input end of is the throttle valve opening correction amount inference device (22B)
Is connected to the output end of the throttle valve opening basic amount calculation device (22A) and the throttle valve opening basic amount and the throttle valve opening correction amount inference device (22A).
The throttle valve opening determination device (23) for determining the throttle valve opening from the throttle valve opening correction amount obtained in B) and (d) the output end of the throttle valve opening determination device (23). The first input end is connected and the second input end is connected to the output end of the throttle valve opening detection device, and the throttle valve opening and throttle valve determined by the throttle valve opening determination device (23) Throttle valve opening / closing operation amount determining device (24) for determining the throttle valve opening / closing operation amount according to the throttle valve opening detection value detected by the opening detection device (24)
And (e) an input end is connected to the output end of the vehicle speed detection device, and a vehicle speed holding device (25) for holding the detected vehicle speed detected by the vehicle speed detection device intermittently and outputting it as the previous vehicle speed,
(f) The first input end is connected to the output end of the vehicle speed detection device and the second input end is connected to the output end of the vehicle speed setting device, and the vehicle speed deviation is calculated from the set vehicle speed and the detected vehicle speed. The vehicle speed deviation calculating device (26) for outputting, and (g) the first input end is connected to the output end of the vehicle speed detecting device, and the second input end is connected to the output end of the vehicle speed holding device (25). The vehicle speed change calculation device (27) for calculating and outputting the vehicle speed change from the detected vehicle speed given by the vehicle speed detection device and the previous vehicle speed given by the vehicle speed holding device (25), and (h) vehicle speed Deviation calculator (2
The first input end is connected to the output end of 6) and the second input end is connected to the output end of the vehicle speed change calculation device (27), and a fuzzy set relating to vehicle speed deviation and a fuzzy set relating to vehicle speed change and throttle A throttle valve opening / closing operation amount inference device for obtaining a throttle valve opening / closing operation amount by fuzzy inference according to a vehicle speed deviation and a vehicle speed change based on a second fuzzy rule established between a fuzzy set relating to the valve opening / closing operation amount ( 28) and (i) the first input end is connected to the output end of the throttle valve opening / closing manipulated variable determining device (24) and the second input end is connected to the output end of the throttle valve opening / closing manipulated variable inferring device (28). A throttle valve opening / closing signal is connected for a predetermined period that starts the throttle valve opening / closing operation amount given from the throttle valve opening / closing operation amount determination device (24) at the start of constant speed running. The throttle valve opening / closing device and the throttle valve opening / closing operation amount given from the throttle valve opening / closing operation amount inference device (28) after a predetermined period starting at the time of constant speed running is used as a throttle valve opening / closing signal. And a selector device (28) for giving to the opening / closing device.

[0008]

The constant speed running control system for an automobile according to the present invention comprises:
As clearly stated in the above-mentioned [Means for Solving Problems], the vehicle travels while adjusting the throttle valve opening according to the set vehicle speed given by the vehicle speed setting device and the detected vehicle speed given by the vehicle speed detection device. A constant speed running control device for an automobile, which is controlled to maintain a speed at a set vehicle speed,
(a) The input end is connected to the output end of the vehicle speed setting device,
A throttle valve opening basic amount calculation device for calculating the basic amount of throttle valve opening based on the set vehicle speed given by the vehicle speed setting device, and (b) the first input end is connected to the output end of the vehicle speed setting device. And the second input end is connected to the output end of the intake manifold negative pressure detecting device, and between the fuzzy set regarding the set vehicle speed, the fuzzy set regarding the intake manifold negative pressure, and the fuzzy set regarding the throttle valve opening correction amount. Based on the first fuzzy rule that holds, according to the set vehicle speed and the intake manifold negative pressure, a throttle valve opening correction amount inference device for obtaining a throttle valve opening correction amount by fuzzy inference, and (c) throttle valve opening The first input end is connected to the output end of the degree basic amount calculation device and the second input end is connected to the throttle valve opening correction amount inference device. The throttle valve opening amount is connected to the power end, and the throttle valve opening amount is calculated from the throttle valve opening basic amount calculated by the throttle valve opening basic amount calculation device and the throttle valve opening correction amount obtained by the throttle valve opening correction amount inference device. The throttle valve opening determining device for determining the degree of rotation, and (d) the first input end is connected to the output end of the throttle valve opening determining device and the second input end is the output of the throttle valve opening detecting device. The throttle valve opening / closing operation amount is connected to the end, and determines the throttle valve opening / closing operation amount according to the throttle valve opening degree determined by the throttle valve opening degree determining device and the throttle valve opening degree detection value detected by the throttle valve opening degree detecting device. The input end is connected to the output of the throttle valve opening / closing operation amount determination device for A vehicle speed holding device for intermittently holding the vehicle speed detected by the vehicle speed detection device and outputting it as the previous vehicle speed; and (f) a first input end connected to the output end of the vehicle speed detection device and a second input end. Is connected to the output end of the vehicle speed setting device, the vehicle speed deviation calculating device for calculating and outputting the vehicle speed deviation from the set vehicle speed and the detected vehicle speed, and (g) the first input at the output end of the vehicle speed detecting device. The end is connected and the second input end is connected to the output end of the vehicle speed holding device, and the vehicle speed change is calculated from the detected vehicle speed given by the vehicle speed detection device and the previous vehicle speed given by the vehicle speed holding device. The first input end is connected to the output end of the vehicle speed change calculation device for outputting (h) the vehicle speed deviation calculation device, and the second input end is connected to the output end of the vehicle speed change calculation device. Fuzzy set for deviation and fuzzy for vehicle speed change Throttle valve opening / closing operation amount for obtaining the throttle valve opening / closing operation amount by fuzzy inference according to the vehicle speed deviation and the vehicle speed change based on the second fuzzy rule established between the fuzzy set and the fuzzy set regarding the throttle valve opening / closing operation amount. The reasoning device and (i) the first input end is connected to the output end of the throttle valve opening / closing manipulated variable determining device and the second input end is connected to the output end of the throttle valve opening / closing manipulated variable inferring device. The throttle valve opening / closing operation amount given from the valve opening / closing operation amount determining device is given to the throttle valve opening / closing device as a throttle valve opening / closing signal for a predetermined period starting at the start of constant speed traveling, and the predetermined period starting at the start of constant speed traveling After that, the throttle valve opening / closing operation amount given by the inference device is calculated. Since it is equipped with a selection device for giving the throttle valve opening / closing signal as a rottle valve opening / closing signal, it has the function of (i) smoothing the change in vehicle speed from the start of constant speed running, and (ii) constant speed. It has the effect of stabilizing the running of the vehicle from the start of running, and consequently (iii) the effect of improving the riding comfort from the start of running at constant speed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a constant speed running control system for an automobile according to the present invention will be specifically described with reference to the accompanying drawings with reference to its preferred embodiments.

However, the embodiment described below
It is described to facilitate or facilitate understanding of the present invention, and not to limit the present invention.

In other words, each element disclosed in the embodiments described below includes all design changes and equivalent replacements within the spirit and technical scope of the present invention.

(Attached Drawing)

FIG. 1 is a block circuit diagram showing an embodiment of a vehicle constant speed running control apparatus according to the present invention.

FIG. 2 is a graph for explaining the operation of the embodiment shown in FIG. 1, and particularly shows one example of a fuzzy set used in fuzzy inference in the throttle valve opening correction amount inference device 22B. ing.

FIG. 3 is a graph for explaining the operation of the embodiment shown in FIG. 1, and particularly shows one example of fuzzy reasoning in the throttle valve opening correction amount reasoning device 22B.

FIG. 4 is a graph for explaining the operation of the embodiment shown in FIG. 1, particularly showing an example of a fuzzy set used in fuzzy inference in the throttle valve opening / closing operation amount inference device 28. There is.

FIG. 5 is a graph for explaining the operation of the embodiment shown in FIG. 1, and particularly shows one example of fuzzy inference in the throttle valve opening / closing operation amount inference device 28.

FIG. 6 is a graph for explaining the operation of the embodiment shown in FIG. 1, and in particular, the opening change of the throttle valve when the vehicle speed setting device 21 sets the vehicle speed to 40 km / hour. And the actual vehicle speed are shown.

FIG. 7 is a block circuit diagram showing an example of a conventional vehicle constant-speed traveling control device.

FIG. 8 is a graph for explaining the operation of the conventional example shown in FIG. 7, and in particular, the opening change of the throttle valve when the vehicle speed setting device 21 sets the vehicle speed to 40 km / hour. And the actual vehicle speed are shown.

(Structure of Example)

First, referring to FIG. 1, the configuration of an embodiment of a vehicle constant speed running control device according to the present invention will be described in detail.

Reference numeral 10 denotes a vehicle constant-speed traveling control device according to the present invention, which constantly detects the actual vehicle speed (that is, the traveling speed of the vehicle) and detects the detection result as the vehicle speed (that is, the actual vehicle speed) S ₁ A vehicle speed detection device 11 for outputting as
An intake manifold negative pressure detection device 12 which is arranged for an intake manifold (not shown) and detects the pressure in the intake manifold and outputs it as an intake manifold negative pressure S ₂ , and a throttle valve (not shown). ) Is attached to the throttle valve opening detection device 13 for detecting the opening and outputting the detection result as the throttle valve opening detection value S ₄ , the output end of the vehicle speed detection device 11, and the intake manifold negative pressure detection. The first to third output ends are connected to the output end of the device 12 and the output end of the throttle valve opening detection device 13, respectively. The detected vehicle speed S ₁ given from the vehicle speed detection device 11 and the intake manifold negative pressure In accordance with the intake manifold negative pressure S ₂ given by the detector 12 and the throttle valve opening detection value S ₄ given by the throttle valve opening detector 13, An arithmetic unit 20 for obtaining the throttle valve opening / closing operation amount and giving it to the throttle valve opening / closing device 14 as a throttle valve opening / closing signal S ₉ . The throttle valve opening detecting device 13 is usually attached to the throttle valve opening / closing device 14 and detects the vehicle speed as the opening of the throttle valve.

The arithmetic unit 20 has an input end connected to the output end of the vehicle speed detecting device 11, and the driver operates a constant speed traveling start switch (not shown) for the purpose of setting or changing the vehicle speed during constant speed traveling. When the vehicle speed setting device 21 for holding the detected vehicle speed S ₁ given from the vehicle speed detection device 11 and outputting it as the set vehicle speed S ₁ ^* when operated, an input end is connected to the output end of the vehicle speed setting device 21. A throttle valve opening basic amount calculating device 22A for appropriately calculating and outputting the throttle valve opening basic amount S ₃₁ by a predetermined conversion formula according to the set vehicle speed S ₁ ^* given from the cage vehicle speed setting device 21. The first input end is connected to the output end of the vehicle speed setting device 21 and the second input end is connected to the output end of the intake manifold negative pressure detection device 12, and the set vehicle speed S given from the vehicle speed setting device 21 is ₁ ^* and the intake manifold negative pressure A throttle valve opening correction quantity estimating device 22B for outputting seeking throttle valve opening correction amount S ₃₂ by fuzzy inference will be described later according to an intake manifold negative pressure S ₂ supplied from the device 12, the throttle valve opening The first input end is connected to the output end of the basic amount calculation device 22A and the second input end is connected to the output end of the throttle valve opening correction amount inference device 22B. The throttle valve opening basic amount S ₃₁ given by the above and the throttle valve opening correction amount S ₃₂ given by the throttle valve opening correction amount inferring device 22B are added to each other to determine the throttle valve opening S ₃₃ and output. For controlling the throttle valve opening degree, and a first input terminal is connected to the output terminal of the throttle valve opening degree determining apparatus 23 and the second input terminal is a slot. Valve opening detecting device 13 throttle valve opening detection value S and the throttle valve opening S ₃₃ supplied from the connected and the throttle valve opening degree determining device 23 to the output terminal provided from the throttle valve opening detecting device 13 of the ₄ is compared with each other (for example, the throttle valve opening detection value S ₄ is subtracted from the throttle valve opening S ₃₃ ) and the comparison result (subtraction result here) is output as the first throttle valve opening / closing operation amount S _5. Throttle valve opening / closing operation amount determination device
24 and.

The arithmetic unit 20 has an input end connected to the output end of the vehicle speed detecting device 11 and intermittently outputs the detected vehicle speed S ₁ given by the vehicle speed detecting device 11 every predetermined time (for example, 1 minute). A first input end is connected to the output end of the vehicle speed detection device 11 and a second input end is connected to the output end of the vehicle speed setting device 12 and a vehicle speed holding device 25 for holding and continuing to output as the previous vehicle speed S _6. The detected vehicle speed S ₁ given by the vehicle speed detection device 11 and the set vehicle speed S given by the vehicle speed setting device 12
₁ ^* and the vehicle speed deviation _{S 71 (= S 1 -S 1} *) vehicle speed deviation calculation unit 26 for calculating and continues to output in response to a first input terminal connected to the output terminal of the vehicle speed detection device 11 The second input end is connected to the output end of the vehicle speed holding device 25, and the vehicle speed is determined according to the detected vehicle speed S ₁ given by the vehicle speed detection device 11 and the previous vehicle speed S ₆ given by the vehicle speed holding device 25. Change S ₇₂ (=
The vehicle speed change calculation device 27 for calculating and continuously outputting S ₁ -S ₆ ), and the first input end is connected to the output end of the vehicle speed deviation calculation device 26 and the second input end is the vehicle speed change calculation device. The second throttle valve opening / closing is connected to the output terminal of 27 according to the vehicle speed deviation S ₇₁ given from the vehicle speed deviation calculating device 26 and the vehicle speed change S ₇₂ given from the vehicle speed change calculating device 27 by fuzzy reasoning described later. A throttle valve opening / closing operation amount inference device 28 for obtaining and outputting the operation amount S ₈ is provided.

In the arithmetic unit 20 , the first input end is connected to the output end of the throttle valve opening / closing operation amount determining device 24 and the second input end is connected to the output end of the throttle valve opening / closing operation amount inferring device 28. In order to apply one of the first throttle valve opening / closing operation amount S ₅ and the second throttle valve opening / closing operation amount S ₈ to the throttle valve opening / closing device 14 as a throttle valve opening / closing signal S ₉ . A selection device 29 is provided.

(Operation of Example)

Further, referring to FIGS. 1 to 5, the operation of one embodiment of the vehicle constant speed traveling control device according to the present invention will be described in detail.

Throttle valve opening basic amount calculation device 22A,
Since it is very complicated to try to generalize and explain the operation of the throttle valve opening correction amount inference device 22B, the throttle valve opening determination device 23, the throttle valve opening / closing operation amount inference device 28, etc., here, Detection result of the detected vehicle speed S ₁ given from the vehicle speed detection device 11, the set vehicle speed S ₁ ^* given from the vehicle speed setting device 21, the intake manifold negative pressure S ₂ given from the intake manifold negative pressure detection device 12, and the vehicle speed retention The case where the previous vehicle speed S ₆ given from the device 25 is as shown in Table 1 will be described as an example.

[0030]

[Table 1]

Detection of vehicle speed S ₁

The vehicle speed detecting device 11 constantly detects the vehicle speed (that is, the traveling speed of the vehicle), and the detected result is detected as the vehicle speed S.
₁ is output to the vehicle speed setting device 21, the vehicle speed holding device 25, the vehicle speed deviation calculation device 26, and the vehicle speed change calculation device 27.

Maintaining the set vehicle speed S ₁ ^*

The vehicle speed setting device 21 detects a detected vehicle speed S ₁ (here, detected vehicle speed S ₁ given by the vehicle speed detection device 11 when the driver operates the constant speed traveling start switch for the purpose of setting or changing the vehicle speed during constant speed traveling. 40 Km / hour) as the set vehicle speed S ₁ ^* , and the throttle valve opening basic amount calculation device 22A, the throttle valve opening correction amount inference device 22B and the vehicle speed deviation calculation device until the constant speed running start switch is operated again. 26
Continues to output to.

Calculation of the throttle valve opening basic amount S ₃₁

Throttle valve opening basic amount calculation device 22A
Is the throttle valve opening basic amount S ₃₁ calculated based on an appropriate conversion formula held in advance according to the set vehicle speed S ₁ ^* (here 40 Km / hour) given from the vehicle speed setting device 21, and the throttle valve It continues to output toward the opening degree determining device 23. The conversion formula held in the throttle valve opening basic amount calculation device 22A is appropriately determined in advance according to the traveling characteristics of the vehicle, etc., but is generally shown in the form of a primary expression or a quadratic expression.

Here, for convenience of explanation, the set vehicle speed S ₁ ^*
It is assumed that the throttle valve opening basic amount S ₃₁ corresponding to (here, 40 km / hour) is calculated as 30%.

Inference of throttle valve opening correction amount S ₃₂

Throttle valve opening correction amount inference device 22B
Is a fuzzy set relating to the set vehicle speed S ₁ ^* given from the vehicle speed setting device 21 (for example, fuzzy set A in FIG. 2 (a)).
And a fuzzy set relating to the intake manifold negative pressure S ₂ given from the intake manifold negative pressure detecting device 12 (for example, fuzzy set B in FIG. 2B) and a fuzzy set relating to the throttle valve opening correction amount S ₃₂ (see FIG. 2 ( The first fuzzy rule that holds between c) and the fuzzy set C)
Based on (for example, the fuzzy rules f _{1 to} f ₅ shown in Table 2), the set vehicle speed S ₁ ^* given by the vehicle speed setting device 21 and the intake manifold negative pressure S ₂ given by the intake manifold negative pressure detecting device 12 Accordingly, the throttle valve opening correction amount S ₃₂ is obtained by fuzzy reasoning. For the purpose of simplifying the explanation, the fuzzy inference in the throttle valve opening correction amount inferring device 22B is shown in Table 2 which is established between the fuzzy sets A to C shown in FIGS. 2 (a) to 2 (c). It will be exemplarily described as being executed based on the fuzzy rules f _{1 to} f ₅ . Therefore, in the present invention, if desired,
(i) membership function included in the fuzzy set _{A~C Z A, S A, L} A; Z B, S B, L B; NL C, NS C, ZR C, PS C, P
L _C may be increased or decreased, or its shape may be changed, and (ii) the number of fuzzy rules f _{1 to} f ₅ may be increased or decreased, or the contents thereof may be changed.

[0040]

[Table 2]

Throttle valve opening correction amount inference device 22B
Is based on Table 1 and FIG. 2 (a) ~ (c) , set in the fuzzy rule f ₁ ~f ₅ of Table 2 speed S ₁ ^* and the membership function of the intake manifold negative pressure S ₂ Z _A, S _A , L _A ;
The degree of affiliation (that is, grade) of Z _B , S _B , and L _B is shown in FIG.
Calculate as shown in (a) and (b) and Table 3.

[0042]

[Table 3]

Throttle valve opening correction amount inference device 22B
Is After that, for each of the fuzzy rules f ₁ ~f _5, set vehicle speed S ₁ ^* and the membership function Z _A of the intake manifold negative pressure _{S 2, S A, L A} ; Z B, S B, L B The degree of affiliation (that is, grade) is compared, and the minimum one among them is shown in Table 3, and the throttle valve opening correction amount S
₃₂ membership function NL _{C of, NS C, ZR C, PS} C, PL
The degree of affiliation (that is, grade) of _C.

Throttle valve opening correction amount inference device 22B
Further, regarding the fuzzy rules f _{1 to} f ₅ , each membership function NL _C , N of the throttle valve opening correction amount S ₃₂ is
_{S C, ZR C, PS C} , and PL _C, the membership functions P of ladder-shaped cut at the position of the grade explicitly in Tables 3
It is transformed into S _C ^{* 1} and ZR _C ^* 3 (see FIG. 3 (c)).

Throttle valve opening correction amount inference device 22B
Is the ladder-shaped membership function PS _C created above
^{* 1,} ZR _C ^{* 3} for enclosed hatched area in FIG. 3
The center of gravity is calculated as shown in (c), and the abscissa of 3.24% is inferred as the throttle valve opening correction amount S ₃₂ , which is output to the throttle valve opening determination device 23.

Determination of throttle valve opening S ₃₃

The throttle valve opening degree determining device 23 provides the slot valve opening basic amount S ₃₁ (that is, 30%) provided by the throttle valve opening basic amount calculating device 22A and the throttle valve opening correction amount inferring device 22B. The throttle valve opening correction amount S ₃₂ (that is, 3.24%) is added to each other to obtain the throttle valve opening S ₃₃ .
33.24% is determined and output to the throttle valve opening / closing operation amount determination device 24.

Generation of throttle valve opening / closing operation amount S ₅

Throttle valve open / close operation amount determination device 24
Is the throttle valve opening S ₃₃ (that is, 33.24%) given by the throttle valve opening determination device 23 and the throttle valve opening detection value S ₄ (31% here) detected by the throttle valve opening detection device 13. And a throttle valve opening / closing operation amount S ₅ (2.24% in this case) are generated and given to the selection device 29.

Maintaining the previous vehicle speed S ₆

The vehicle speed holding device 25 intermittently holds the detected vehicle speed S ₁ (here 40 Km / hour) given from the vehicle speed detection device 11, and changes the vehicle speed S ₁ with the held detected vehicle speed S ₁ as the previous vehicle speed S _6. It continues to output to the calculation device 27.

Calculation of vehicle speed deviation S ₇₁

The vehicle speed deviation calculating device 26 detects the detected vehicle speed S ₁ (42 Km / hour in this case) given by the vehicle speed detecting device 11 and the set vehicle speed S ₁ ^* (40 Km / here in this case) given by the vehicle speed setting device 21.
Time difference) (ie vehicle speed deviation) S ₇₁ (here 2K
m / h) is calculated and output to the throttle valve opening / closing operation amount inference device 28.

Calculation of vehicle speed change S ₇₂

The vehicle speed change calculating device 27 detects the detected vehicle speed S ₁ (42 Km / hour here) given by the vehicle speed detecting device 11 and the previous vehicle speed S ₆ (40 Km / here here) given by the vehicle speed holding device 25.
Time difference) (ie change in vehicle speed) S ₇₂ (here 2
Km / hour) is calculated and output to the throttle valve opening / closing operation amount inference device 28.

Inference of throttle valve opening / closing operation amount S ₈

Throttle valve opening / closing operation amount inference device 28
Is a fuzzy set (for example, fuzzy set D in FIG. 4A) related to the vehicle speed deviation S ₇₁ given from the vehicle speed deviation calculation device 26 and the vehicle speed change S ₇₂ given from the vehicle speed change calculation device 27.
A fuzzy rule (eg, fuzzy set E in FIG. 4 (b)) and a fuzzy set (eg, fuzzy set F in FIG. 4 (c)) relating to the throttle valve opening / closing operation amount S ₈ (see Table 4). Based on the fuzzy rules g _{1 to} g ₁₉ ) shown in FIG. _{2, the} throttle is calculated by fuzzy reasoning according to the vehicle speed deviation S ₇₁ given from the vehicle speed deviation calculation device 26 and the vehicle speed change S ₇₂ given from the vehicle speed change calculation device 27. The valve opening / closing operation amount S ₈ is calculated. For the sake of brevity, the fuzzy reasoning in the throttle valve opening / closing manipulated variable reasoning device 28 is shown in Table 4 which is established between the fuzzy sets D to F shown in FIGS. 4 (a) to 4 (c). It will be exemplarily described as being executed based on the fuzzy rules g _{1 to} g ₁₉ . Therefore, in the present invention, optionally (i) membership function included in the fuzzy set _{D~F NL D, NM D, NS} D, ZR D, PS D, PM D, PL D; NL E,
NM _E , NS _E , ZR _E , PS _E , PM _E , PL _E ; NL _F , NM _F , N
S _F , ZR _F , PS _F , PM _F , PL _F may be increased or decreased or their shape may be changed, and (ii) fuzzy rules g _{1 to} g
You may increase or decrease the number of ₁₉ or change the content.

[0058]

[Table 4]

Throttle valve opening / closing operation amount inference device 28
Is based on Table 1 and FIG. 4 (a) ~ (c) , the membership functions NL _D of the vehicle speed deviation S ₇₁ and the vehicle speed change S ₇₂ in fuzzy rule g ₁ to g ₁₉ of Table 4, NM _D, NS _D , ZR _D ,
PS _D , PM _D , PL _D ; NL _E , NM _E , NS _E , ZR _E , PS _E , P
M _E, belonging of the PL _E (i.e. grade), FIGS. 5 (a)
Calculate as in (b) and Table 5.

[0060]

[Table 5]

Throttle valve opening / closing operation amount inference device 28
Is After that, for each of the fuzzy rules g ₁ to g _19, each membership function NL _D of the vehicle speed deviation S ₇₁ and the vehicle speed change _{S 72, NM D, NS D} , ZR D, PS D, PM D, PL D ;
Affiliation degree of NL _E , NM _E , NS _E , ZR _E , PS _E , PM _E , PL _E
(That is, grade) is compared, and the smallest one is shown in Table 5, and the throttle valve opening / closing operation amount S ₈
Membership functions NL _F , NM _F , NS _F , ZR _F , PS _F ,
The degree of affiliation (that is, grade) of PM _F and PL _F.

Throttle valve opening / closing operation amount inference device 28
Further, regarding the fuzzy rules g _{1 to} g ₁₉ , each membership function NL _F , N of the throttle valve opening / closing operation amount S ₈ is
_{M F, NS F, ZR F} , NS F, PS F, the PL _F, respectively Table 5
It is transformed into a ladder-shaped membership function NS _F ^{* 6} , ZR _F ^{* 10} , NS _F ^{* 11} , which is cut at the grade position specified in Figure 5 (c). Here, the grade specified in Table 5 is 0.
Since the height of the ladder-shaped membership function corresponding to the case of 0 is 0, the display is omitted.

Throttle valve opening / closing operation amount inference device 28
Is the ladder-shaped membership function NS _F created above
Calculate the center of gravity of the hatched area surrounded by ^{* 6} , ZR _F ^{* 10} and NS _F ^{* 11} as shown in Fig. 5 (c), and infer that abscissa of -3.85% is the throttle valve opening / closing operation amount S _8. , To the selection device 29.

Selection of throttle valve opening / closing operation amounts S ₅ and S ₈
Choice

When the driver operates the constant speed running start switch, the selection device 29 determines the throttle valve opening / closing operation amount only for a predetermined period (for example, 5 minutes) which starts when the driver operates the constant speed running start switch (that is, when the constant speed running starts). The throttle valve opening / closing operation amount S ₅ given from the device 24 is given to the throttle valve opening / closing device 14 as a throttle valve opening / closing signal S ₉ , and for another period (that is, after a lapse of a predetermined period started at the start of constant speed running). The throttle valve opening / closing operation amount S ₈ given from the throttle valve opening / closing operation amount inference device 28 is given to the throttle valve opening / closing device 14 as a throttle valve opening / closing signal S ₉ .

The throttle valve opening / closing device 14 opens / closes the throttle valve according to the throttle valve opening / closing signal S ₉ (that is, the throttle valve opening / closing operation amount S ₅ ) for a predetermined period when the driver operates the constant speed running start switch.
(Here, open only 2.24%). As a result, the throttle valve is opened or closed by the amount corresponding to the throttle valve opening / closing signal S ₉ (that is, the throttle valve opening / closing operation amount S ₅ ) from the previous opening (for example, 31%) (here Will be 33.24%).

After that, the throttle valve opening / closing device 14 opens / closes the throttle valve (closed by 3.85% in this case) in response to the throttle valve opening / closing signal S ₉ (that is, the throttle valve opening / closing operation amount S ₈ ). As a result, the throttle valve is opened or closed by the amount corresponding to the throttle valve opening / closing signal S ₉ (that is, the throttle valve opening / closing operation amount S ₈ ) from the previous opening (for example, 31%) (here 27.15%).

Therefore, according to the present invention, when the vehicle is traveling at a constant speed, the change in the vehicle speed is smoothed from the start thereof, and when the vehicle is traveling at a constant speed, the traveling of the vehicle is stabilized from the start of the vehicle. It has the effect of improving the riding comfort from the start.

(Specific example)

In addition, in order to facilitate the understanding of one embodiment of the vehicle constant speed traveling control apparatus according to the present invention, more detailed description will be given with reference to numerical values and the like.

Example

Constant Speed Driving Control Device for Vehicle According to the Present Invention
For the purpose of investigating the performance of the tenth embodiment, a running test of a vehicle equipped with one embodiment of the vehicle constant speed running control device 10 according to the present invention was conducted.

When the vehicle speed S ₁ detected by the vehicle speed detecting device 11 (that is, the actual vehicle speed) becomes 40 Km / hour, the driver operates the constant speed running start switch to give the vehicle speed setting device 21 from the vehicle speed detecting device 11. When the constant speed running is started by maintaining the detected vehicle speed S ₁ that has been detected, the selection device 29 generates the throttle valve opening / closing operation amount S generated by the throttle valve opening / closing operation amount determining device 24 for a predetermined period (here, 5 minutes).
₅ is given to the throttle valve opening / closing device 14 as the throttle valve opening / closing signal S ₉ , and the detection result of the throttle valve opening detection device 13 (that is, the throttle valve opening detection value) S ₄ is shown in FIG. 6 (a). Changes as shown,
The vehicle speed detected by the vehicle speed detection device 11 (that is, the actual vehicle speed)
S ₁ changed as shown in FIG. 6 (b).

When a predetermined period (here, 5 minutes) elapses after the driver operates the constant speed running start switch, the selection device 29 generates the throttle valve opening / closing operation amount inference device 28 in place of the throttle valve opening / closing operation amount S _5. The throttle valve opening / closing operation amount S ₈ is given to the throttle valve opening / closing device 14 as a throttle valve opening / closing signal S ₉ , and along with this, the detection result of the throttle valve opening detection device 13 (that is, the throttle valve opening detection value) S ₄ Changes slowly,
The vehicle speed detected by the vehicle speed detection device 11 (that is, the actual vehicle speed)
S ₁ changed slowly.

Comparative Example

For the purpose of investigating the performance of the conventional vehicle constant speed traveling control device, a traveling test of an automobile equipped with the conventional vehicle constant speed traveling control device shown in FIG. 7 was conducted.

The conventional vehicle constant-speed traveling control device 30 shown in FIG. 7 constantly detects the actual vehicle speed (that is, the traveling speed of the vehicle), and the detected result is the detected vehicle speed (that is, the actual vehicle speed).
A vehicle speed detection device 31 for outputting as S ₁ and an input end connected to the output end of the vehicle speed detection device 31 are used by the driver for the purpose of setting or changing the constant speed traveling vehicle speed. And a vehicle speed setting device 32 for holding the detected vehicle speed S ₁ given from the vehicle speed detection device 31 and outputting it as a set vehicle speed S ₁ ^* , and a vehicle speed detection device 31.
The first input end is connected to the output end of the vehicle and the second input end is connected to the output end of the vehicle speed setting device 32.
According to the detected vehicle speed S ₁ given from 31 and the set vehicle speed S ₁ ^* given from the vehicle speed setting device 32, a vehicle speed deviation S ₇ (= S ₁ −
Vehicle speed deviation calculating device for calculating and continuously outputting S ₁ ^* )
33, and an input end is connected to the output end of the vehicle speed setting device 32, and the throttle valve opening basic amount S ₃₁ is appropriately changed by a predetermined conversion formula according to the set vehicle speed S ₁ ^* given from the vehicle speed setting device 32. A throttle valve opening basic amount calculation device 34A for calculating and outputting, and an input end connected to the output end of the vehicle speed deviation calculation device 33, and the throttle according to the vehicle speed deviation S ₇ given from the vehicle speed deviation calculation device 33. Valve opening correction amount S
A throttle valve opening correction amount calculation device 34B for appropriately calculating and outputting ₃₂ using the same conversion formula as the conversion formula used in the throttle valve opening basic amount calculation device 34A,
The first input end is connected to the output end of the throttle valve opening basic amount calculation device 34A and the second input end is connected to the output end of the throttle valve opening correction amount calculation device 34B. The throttle valve opening basic amount S ₃₁ given by the amount calculation device 34A and the throttle valve opening correction amount S ₃₂ given by the throttle valve opening correction amount calculation device 34B are added to each other to add the throttle valve opening S _33. For determining and outputting the throttle valve opening determining device 35 and a throttle valve (not shown) for detecting the opening and outputting the detection result as a throttle valve opening detection value S _4. The first input end is connected to the output ends of the throttle valve opening detection device 36 and the throttle valve opening determination device 35, and the second input end is connected to the throttle valve opening detection device. Throttle valve opening S ₃₃ provided from the throttle valve opening degree determining device 35 is connected to an output terminal 36 and the throttle valve opening detecting device
The throttle valve opening detection value S ₄ given from 36 is compared with each other (for example, the throttle valve opening S ₃₃ is subtracted from the throttle valve detection value S ₄ ) and the comparison result (the subtraction result here) is calculated. S ₅
And a throttle valve opening / closing operation amount determining device 37 for outputting as a throttle valve opening / closing signal to the throttle valve opening / closing device 38. The throttle valve opening detecting device 36 is attached to the throttle valve opening / closing device 38 and detects the vehicle speed as the opening of the throttle valve.

When the vehicle speed S ₁ detected by the vehicle speed detecting device 31 (that is, the actual vehicle speed) is 40 Km / hour, the driver operates the constant speed running start switch to give the vehicle speed setting device 32 from the vehicle speed detecting device 31. When constant speed running is started by maintaining the detected vehicle speed S ₁ that is detected, the detection result (that is, throttle valve opening) S _{4 of} the throttle valve opening detection device 36 changes as shown in FIG. 8 (a). In addition, the vehicle speed S ₁ detected by the vehicle speed detection device 31 (that is, the actual vehicle speed) S ₁ changes as shown in FIG. 8 (b).

(Comparison between Example and Comparative Example)

As is clear from comparison between the embodiment and the comparative example, according to the present invention, the detection result of the throttle valve opening detection device 13 (that is, the throttle valve opening detection value) S ₄ is higher than that of the comparative example. Even if the change in the vehicle speed is steep during constant speed running, the vehicle speed detected by the vehicle speed detection device 11 from the beginning
(That is, the actual vehicle speed) S ₁ can be changed smoothly, and as a result, stable running of the vehicle can be secured from the start thereof, and as a result, the riding comfort can be improved from the start thereof.

(Modification)

In the above description, the fuzzy inference is performed by cutting the top of the membership function to obtain the center of gravity, but the present invention is not limited to this and other well-known points can be used. It also includes cases where fuzzy inference is performed (for example, by changing the height of the membership function to find the center of gravity). In other words, the present invention does not limit fuzzy reasoning to a fixed one.

Further, in the above, the throttle valve opening basic amount calculating device 22A, the throttle valve opening correction amount inferring device
22B, throttle valve opening determination device 23, throttle valve opening / closing operation amount determination device 24, vehicle speed deviation calculation device 26, vehicle speed change calculation device 27, throttle valve opening / closing operation amount inference device 28
Although the case where the selection device 29 and the selection device 29 are configured by independent circuit elements has been described, the present invention is not limited to this, and includes a case where they are configured by a computer.

[0084]

As is apparent from the above, the constant speed running control system for an automobile according to the present invention has a [Means for Solving Problems].
As clearly indicated in the column, the vehicle speed should be maintained at the set vehicle speed while adjusting the throttle valve opening according to the set vehicle speed given by the vehicle speed setting device and the detected vehicle speed given by the vehicle speed detection device. This is a constant-speed traveling control device for an automobile that is controlled. (A) The input end is connected to the output end of the vehicle speed setting device, and the throttle valve opening based on the set vehicle speed given from the vehicle speed setting device. Throttle valve opening basic amount calculation device for calculating the basic amount
(b) The first input end is connected to the output end of the vehicle speed setting device and the second input end is connected to the output end of the intake manifold negative pressure detecting device, and the fuzzy set and the intake manifold negative pressure related to the set vehicle speed are connected. To obtain the throttle valve opening correction amount by fuzzy inference according to the set vehicle speed and the intake manifold negative pressure, based on the first fuzzy rule established between the fuzzy set regarding the throttle valve opening correction amount and the fuzzy set regarding the throttle valve opening correction amount. Of the throttle valve opening correction amount inference device of (c), and the first input end is connected to the output end of the throttle valve opening basic amount calculation device, and the second input end is connected to the throttle valve opening correction amount inference device. Connected to the output end, the throttle valve opening basic amount and throttle valve opening calculated by the throttle valve opening basic amount calculation device A throttle valve opening degree determining apparatus for determining a throttle valve opening degree from a throttle valve opening correction amount determined by Seiryo inference apparatus,
(d) The first input end is connected to the output end of the throttle valve opening determination device and the second input end is connected to the output end of the throttle valve opening detection device. A throttle valve opening / closing operation amount determining device for determining the throttle valve opening / closing operation amount according to the determined throttle valve opening and the throttle valve opening detection value detected by the throttle valve opening detection device, and (e) An input end is connected to the output end of the vehicle speed detection device, and a vehicle speed holding device for intermittently holding the vehicle speed detected by the vehicle speed detection device and outputting it as the previous vehicle speed, and (f) an output end of the vehicle speed detection device. Is connected to a first input end and a second input end is connected to an output end of the vehicle speed setting device, and a vehicle speed for calculating and outputting a vehicle speed deviation from the set vehicle speed and the detected vehicle speed. The difference calculation device and (g) the first input end is connected to the output end of the vehicle speed detection device, and the second input end is connected to the output end of the vehicle speed holding device. A vehicle speed change calculation device for calculating and outputting a vehicle speed change from a vehicle speed and a previous vehicle speed given by a vehicle speed holding device, and (h) a first input end is connected to the output end of the vehicle speed deviation calculation device and The input end of 2 is connected to the output end of the vehicle speed change calculation device, and the second fuzzy rule established between the fuzzy set regarding the vehicle speed deviation, the fuzzy set regarding the vehicle speed change, and the fuzzy set regarding the throttle valve opening / closing operation amount is applied. Based on the vehicle speed deviation and the vehicle speed change, a throttle valve opening / closing operation amount inference device for obtaining the throttle valve opening / closing operation amount by fuzzy inference, and (i) a throttle valve opening / closing operation amount determining device The first input end is connected to the output end of the throttle valve and the second input end is connected to the output end of the throttle valve opening / closing manipulated variable reasoning device, and the throttle valve opening / closing provided by the throttle valve opening / closing manipulated variable determining device is opened. The operation amount is given to the throttle valve opening / closing device as a throttle valve opening / closing signal for a predetermined period starting at the start of constant speed running, and given from the throttle valve opening / closing operation amount inference device after a lapse of a predetermined period starting at the start of constant speed running. Since it is equipped with a selection device for giving the throttle valve opening / closing operation amount to the throttle valve opening / closing device as a throttle valve opening / closing signal, (i) it has the effect of making it possible to smoothly change the vehicle speed from the start at constant speed running. As a result, (ii) it has the effect of stabilizing the running of the vehicle from the start during constant speed running, and as a result (iii) It has an effect that can improve the ride comfort from the start upon traveling.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing an embodiment of a vehicle constant-speed traveling control device according to the present invention.

FIG. 2 is a graph for explaining the operation of the embodiment shown in FIG.

FIG. 3 is a graph for explaining the operation of the embodiment shown in FIG.

FIG. 4 is a graph for explaining the operation of the embodiment shown in FIG.

FIG. 5 is a graph for explaining the operation of the embodiment shown in FIG.

FIG. 6 is a graph for explaining the operation of the embodiment shown in FIG.

FIG. 7 is a block circuit diagram showing an example of a conventional vehicle constant-speed traveling control device.

FIG. 8 is a graph for explaining the operation of the conventional example shown in FIG.

[Explanation of Codes] 10 ...・ ・ ・ ・ Vehicle speed detector 12 ・ ・ ・ ・ Intake manifold negative pressure detector 13 ・ ・ ・ ・ ・ ・・ ・ ・ Throttle valve opening detector 14 ・ ・ ・ ・ Throttle valve opening / closing device 20・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ Calculator 21 ・ ・ ・ ・ Vehicle speed setting device 22A ・ ・ ・ ・ ・ ・..Throttle valve opening basic amount calculation device 22B .....・ ・ ・ ・ ・ ・ ・ ・ Throttle valve opening determination device 24 ・・ ・ ・ Throttle valve opening / closing operation amount determining device 25 ・ ・ ・ ・ ・ ・ ・ Vehicle speed holding device 26・ ・ ・ ・ Vehicle speed deviation calculator 27 ・ ・ ・ ・ Vehicle speed change calculator 28・ ・ ・ ・ ・ ・ ・ Throttle valve opening / closing amount inferring device 29 ・ ・ ・ ・ ・ ・ ・ Selecting device

Claims (1)

[Claims] 1. A throttle valve opening is adjusted in accordance with a set vehicle speed given by a vehicle speed setting device and a detected vehicle speed given by a vehicle speed detection device, and control is performed to maintain the running speed of the vehicle at the set vehicle speed. In the constant speed running control device of the vehicle, which is (a) the input end is connected to the output end of the vehicle speed setting device,
A throttle valve opening basic amount calculation device (22A) for calculating the throttle valve opening basic amount based on the set vehicle speed given from the vehicle speed setting device, and (b) a first input at the output end of the vehicle speed setting device. The ends are connected and the second input end is connected to the output end of the intake manifold negative pressure detection device. A fuzzy set relating to the set vehicle speed, a fuzzy set relating to the intake manifold negative pressure, and a fuzzy set relating to the throttle valve opening correction amount. Based on the first fuzzy rule that holds between, the throttle valve opening correction amount inference device (22B) for obtaining the throttle valve opening correction amount by fuzzy inference according to the set vehicle speed and the intake manifold negative pressure, (c) The first input end is connected to the output end of the throttle valve opening basic amount calculation device (22A) and the second input end is corrected for the throttle valve opening. It is connected to the output end of the quantity inference device (22B), and the throttle valve opening basic amount calculation device (22A)
A throttle valve opening degree determining device for determining the throttle valve opening degree from the throttle valve opening degree basic amount calculated by and the throttle valve opening degree correction amount inferring device (22B)
(23), and (d) the first at the output end of the throttle valve opening determination device (23)
Is connected to the input end of the throttle valve opening detection device and the second input end is connected to the output end of the throttle valve opening detection device. A throttle valve opening / closing operation amount determining device (24) for determining the throttle valve opening / closing operation amount according to the detected value of the throttle valve opening detected by the detection device, and (e) an input end at the output end of the vehicle speed detection device. Is connected,
A vehicle speed holding device (25) for intermittently holding the vehicle speed detected by the vehicle speed detection device and outputting it as the previous vehicle speed, and (f) the first input end is connected to the output end of the vehicle speed detection device and the second The input end of is connected to the output end of the vehicle speed setting device, and the vehicle speed deviation calculation device (26) for calculating and outputting the vehicle speed deviation from the set vehicle speed and the detected vehicle speed, and (g) the output of the vehicle speed detection device The first input end is connected to the end and the second input end is connected to the output end of the vehicle speed holding device (25), and the detected vehicle speed given by the vehicle speed detection device and the vehicle speed holding device (25) are given. A vehicle speed change calculation device (27) for calculating and outputting a vehicle speed change from the obtained previous vehicle speed, and (h) a first input end is connected to an output end of the vehicle speed deviation calculation device (26) and a second The input end of is connected to the output end of the vehicle speed change calculation device (27), and the fuzzy set and the vehicle speed change related to the vehicle speed deviation are connected. Throttle valve for determining the throttle valve opening / closing operation amount by fuzzy inference according to a vehicle speed deviation and a vehicle speed change based on a second fuzzy rule established between a fuzzy set relating to realization and a fuzzy set relating to throttle valve opening / closing operation amount The first input end is connected to the output end of the opening / closing operation amount inference device (28) and (i) the throttle valve opening / closing operation amount determining device (24), and the second input end is the throttle valve opening / closing operation amount inferring device ( 28) is connected to the output end and the throttle valve opening / closing device is used as a throttle valve opening / closing signal for a predetermined period when the throttle valve opening / closing operation amount given by the throttle valve opening / closing operation amount determination device (24) is started at the start of constant speed running. And from the throttle valve opening / closing manipulated variable inferring device (28) after the elapse of a predetermined period starting at the start of constant speed running. A constant speed traveling control device for an automobile, comprising: a selector device (28) for giving the throttle valve opening / closing operation amount as a throttle valve opening / closing signal to the throttle valve opening / closing device.