JP2685768B2 - Vehicle control device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a control device for a vehicle having a constant speed traveling device. (Prior Art) Conventionally, as described, for example, in Japanese Utility Model Application Laid-Open No. 58-14434, a vehicle such as an automobile has a vehicle speed setting means, and when the vehicle speed setting means is operated, it is set by the means. It is known to have a device that allows a vehicle to run at a constant speed at a specified speed. Further, from the viewpoint of improving fuel efficiency, it is also known to cut off the supply of fuel to the engine in a specific operation region (fuel cut region). (Problems to be Solved by the Invention) Therefore, it is conceivable to perform fuel cut in a specific operation region in a vehicle having a constant speed traveling device. However, when driving at a constant speed, the driver's vehicle is isolated from the throttle valve, and when acceleration / deceleration different from the driver's intention occurs, a particularly large torque shock occurs at the time of entry into the fuel cut region and at that time. The driving feeling deteriorates when escaping. It should be noted that such entry into and exit from the fuel cut region is established on a gentle downhill of an expressway. Therefore, in view of the above point, an object of the present invention is to provide a control device for a vehicle that prevents deterioration of traveling feeling due to a change in engine torque. (Means for Solving the Problem) In order to achieve the above object, a solution means of the present invention is a vehicle speed detecting means for detecting a vehicle speed, and an output of the vehicle speed detecting means to feed back the vehicle speed so as to reach a target vehicle speed. In a vehicle having a constant speed traveling device including vehicle speed control means for controlling, an operation detecting device for detecting an operation of the constant speed traveling device, a throttle opening detecting device for detecting a throttle opening, and a throttle opening device. And a fuel cut determination unit that determines that the fuel cut region is in a fuel cut region when the throttle opening amount detected by the fuel amount detection unit is less than or equal to a predetermined throttle opening amount for which fuel cut should be performed. When the determination is made, the fuel cut executing means for executing the fuel cut and the throttle opening detected by the throttle opening detecting means are Discriminating means for discriminating that the deviation between the detected throttle opening and the predetermined throttle opening is within a predetermined value for determining that the throttle opening is approaching, and the operation detecting means and the discrimination. The vehicle speed control means receives the output of the vehicle speed control means during the period in which the vehicle is traveling at a constant speed by the operation of the constant speed traveling device and the deviation between the detected throttle opening and the predetermined throttle opening is within a predetermined value. It is assumed to be provided with a correction means for correcting so as to reduce the control response when performing the vehicle speed control. (Operation) As a result, in the present invention, when the vehicle is traveling at a constant speed and the deviation between the detected throttle opening and the predetermined throttle opening for determining the fuel cut is within a predetermined value, the fuel cut line is approached. During the period when it is determined that the vehicle speed is determined, the responsiveness of the control by the vehicle speed control means (for example, the feedback control value) is reduced, so that the frequency of entry into and exit from the fuel cut region is reduced. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In FIG. 1 showing the overall configuration of the vehicle control device, 1
Is an engine body, and an intake passage 2 and an exhaust passage 3 are connected to the combustion chamber 1a thereof. In the intake passage 2,
An air cleaner (not shown), an air flow meter 4, a throttle valve 5 and an injector 6 are arranged in this order from the upstream side. On the other hand, a catalyst device 7 is provided in the exhaust passage 3. The throttle valve 5 is controlled to be opened and closed by an actuator 8 according to the operating state of the engine. Reference numeral 9 is a throttle opening sensor, 10 is an engine speed sensor, 11 is a vehicle speed sensor, and 12 is an accelerator opening sensor. Further, 13 is an auto cruise switch, which constitutes operation detecting means for detecting the operation of the constant speed traveling device. Reference numeral 15 is a controller, which is constructed as shown in FIG. That is, the controller 15 controls the intake air amount signal from the air flow meter 4 and the engine speed sensor 10.
From the engine speed signal and the throttle opening signal from the throttle opening sensor 9. Fuel cut determination means 102 for determining that the fuel cut region is within a predetermined throttle opening for fuel cut,
It has a fuel cut executing means 103 which receives the outputs of both means 101 and 102 and executes fuel cut in the fuel cut region. The controller 15 receives the accelerator opening signal from the accelerator opening sensor 12 and calculates a basic throttle opening calculating means 104, an output of the basic throttle opening calculating means 104, and a vehicle speed sensor 11. And a throttle opening control means 105 as a vehicle speed control means for feedback controlling the throttle opening to the target opening so as to reach the target vehicle speed. Further, the controller 15 sets the detected throttle opening and the predetermined throttle opening in order to determine that the throttle opening detected by the throttle opening sensor 9 is close to the predetermined throttle opening. Discriminating means (not shown) for discriminating that the deviation is within a predetermined value
Of the throttle opening detected in the constant speed traveling state by the operation of the constant speed traveling device and the predetermined throttle opening in response to the output of the automatic cruise switch signal from the automatic cruise switch 13 and the determination means. While the deviation is outside the predetermined value, the throttle opening control means
And a correction unit 106 for correcting the feedback control value by 105. The above-mentioned respective means 104, 105, 106 constitute a throttle control means 107 which performs both normal throttle control and constant speed traveling control. Next, the flow of processing by the controller 15
Description will be made with reference to the drawings. First, when started, reads the engine speed and the intake air amount (step S _1), calculates the injection pulse T of the fuel on the basis of the both signals (step S _2). Then, the auto cruise switch (auto cruise
SW) it is determined whether or not ON (Step S _3), since a long non-constant-speed traveling if OFF, reads the accelerator opening theta _ACC (Step S _4), the accelerator opening by a fourth diagram theta _ACC The target opening θ _TVO of the throttle valve 5 is calculated based on (step S ₅ ), and a throttle control signal is output to the actuator 8 so that the throttle opening becomes the target opening θ _TVO (step S ₆ ). Go to step S ₇ . On the other hand, if the auto cruise SW is ON, it means that the vehicle is traveling at a constant speed.
Without performing the process of S ₄ to S _6, the process proceeds to step S _7. In step S ₇ , the throttle opening TV _O is read and the fifth
As shown in the figure, the critical throttle opening TV at the current engine speed N _E is determined by the fuel cut determination line l.
Calculated _OFC (predetermined throttle opening determines the fuel cut) (step S _8), the throttle opening TV _O is in order to determine that it is close to the critical throttle opening TV _OFC, the current throttle opening Degree TV _O and critical throttle opening T
It is determined whether the deviation from V _OFC is less than or equal to a predetermined value a, that is, | TV _O −TV _OFC | ≦ a (step S ₉ ). If the deviation | TV _O −TV _OFC | is less than or equal to the predetermined value a, it is determined that the fuel cut determination line 1 is approaching.
The FLAG is set to 1 (step S _10), it is determined whether the fuel cut region, (step S _11), if the fuel cut region out the fuel cut (step S ₁₂₎ On the other hand, the fuel cut If it is not within the region, fuel is injected with the injection pulse T calculated in step S ₂ (step
S _13). On the other hand, if the deviation | TV _O −TV _OFC | exceeds the predetermined value a, it means that the fuel cut line determination line 1 is not approached, and therefore FLAG is set to 0 (step S ₁₄ ), and the process proceeds to step S ₁₃ . Then, it is determined whether re autocruising SW is ON (step S _15), because it is in constant-speed running, if ON, F
It is determined whether the LAG = 1 (step S _16), FLAG =
If it is 1, since the vehicle is traveling at a constant speed and the deviation between the throttle opening TV _O and the critical throttle opening TV _OFC is within the predetermined value a, the feedback control value Δθ is a small value ΔTV _OS.
Lowering the responsiveness of the control with (step S ₁₇₎ On the other hand, FLAG = 1 Otherwise, even during constant speed running, the deviation between the throttle opening TV _O and the critical throttle opening TV _OFC is a predetermined value Since it exceeds a, a large value ΔTV _OL (> TV _OS ) is used as the feedback control value Δθ (step S ₁₈ ), and then the vehicle speed V is read (step S ₁₉ ), and the vehicle speed V is the target vehicle speed V _O and the allowable value a. It is determined whether or not it is greater than the sum of and (step S ₂₀ ). When the vehicle speed V is higher than the above sum V _O + a, the target opening θ _TVO of the throttle valve 5 is reduced by a predetermined value Δθ (step S ₂₁ ), while the routine _proceeds to step S ₂₄ , while when it is smaller,
It is determined whether the vehicle speed V is lower than the target vehicle speed V _O itself (step S ₂₂ ), and if it is smaller, the target opening θ _TVO is increased by a predetermined value Δθ (step S ₂₃ ). Move to S ₂₄ . In step S ₂₄ , the throttle control signal is output to the actuator 8 so that the target opening θ _TVO is _achieved . Note that auto-cruise SW is not the ON, it ends with the determination of step S _15. In this embodiment, the normal throttle control and the constant speed traveling control are performed by the same control means, but they may be controlled independently, and a machine for controlling the throttle valve with a wire may be used. An expression type may be used. Further, in this embodiment, the control response is changed by changing the feedback control value Δθ.
The control response may be lowered by another method such as changing the operating speed of the actuator. (Advantages of the Invention) As described above, according to the present invention, the responsiveness of the control by the vehicle speed control means is reduced during the constant speed traveling state and the period of approaching the fuel cut determination line. During traveling, the frequency of protrusion into and escape from the fuel cut region is reduced, and the traveling feeling can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show an embodiment of the present invention. FIG. 1 is a diagram showing a schematic configuration of a vehicle control device, FIG. 2 is a block diagram showing a configuration of a controller, and FIG. FIG. 4 is a flow chart showing the flow of processing of the controller, FIG. 4 is a diagram showing the relationship between the accelerator opening θ _ACC and the target opening θ _TVO of the throttle valve, and FIG. 5 is a diagram showing a fuel cut determination line. 1 ... Engine body, 6 ... Injector, 12 ... Accelerator opening sensor, 13 ... Auto cruise switch, 15 ...
... Controller, 102 ... Fuel cut determination means, 105 ...
Throttle opening control means 106 ... correction means 107 ... throttle control means.

Claims (1)

(57) [Claims] A vehicle having a constant speed traveling device comprising a vehicle speed detecting means for detecting a vehicle speed, and a vehicle speed control means for receiving an output of the vehicle speed detecting means and feedback-controlling the vehicle speed so as to reach a target vehicle speed. Operation detecting means for detecting the operation of the device, throttle opening detecting means for detecting the throttle opening, and when the throttle opening detected by the throttle opening detecting means is equal to or less than a predetermined throttle opening for fuel cut, A fuel cut determination means for determining that the fuel cut area is present; a fuel cut execution means for executing a fuel cut when the fuel cut determination means determines that the fuel cut area is present; In order to determine that the detected throttle opening is close to the above predetermined throttle opening, the detected throttle opening Means for determining whether the deviation between the vehicle speed and the predetermined throttle opening is within a predetermined value, and the output of the operation detecting means and the determining means, and in the constant speed traveling state by the operation of the constant speed traveling device and And a correction unit for correcting the control response when performing the vehicle speed control by the vehicle speed control unit during a period in which the deviation between the detected throttle opening and the predetermined throttle opening is within a predetermined value. A control device for a vehicle characterized by the following.