JPH07108625B2 - Vehicle control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle control device provided with a so-called constant speed traveling device for automatically traveling a vehicle at a constant speed.

[Prior art]

Conventionally, various so-called constant-speed traveling devices have been developed that automatically drive a vehicle at a constant speed (for example, described in US Pat. No. 3,070,185).

In a vehicle equipped with such a constant-speed traveling device, for example, on a highway or the like, the driver operates a switch or the like to set a speed at which the driver wants constant-speed traveling, and the throttle valve opening is automatically adjusted. Therefore, the driver can continuously drive the vehicle at a desired constant speed, which is very convenient because the driver does not have to constantly press the accelerator pedal.

[Problems to be Solved by the Invention]

However, in the conventional vehicle control device as described above, depending on the state of the control device, the vehicle may not travel at a desired target speed, for example, the actual travel speed may be lower than the target speed.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a vehicle control device that can perform more appropriate control according to the state of the control device.

[Means for Solving the Problems]

 FIG. 1 is a block diagram showing the function of the present invention.

In FIG. 1, 100 is a known constant-speed traveling device, for example, a portion constituted by 1 to 18 in FIGS. 2 and 3 described later, which shows an actual vehicle speed and a designated target vehicle speed. This is a device for automatically running a vehicle at a specified constant speed by controlling the throttle valve opening of the internal combustion engine 101 so as to eliminate the deviation.

Further, 101 is an internal combustion engine, which includes a combustion injection control device, an ignition timing control device, and the like.

Further, 102 is a vehicle speed detecting means for detecting the vehicle speed, and corresponds to, for example, the vehicle speed sensor 24 in FIG. 2 described later. Also,
Reference numeral 103 denotes an accelerator pedal detecting means for detecting whether or not the accelerator pedal is depressed, and corresponds to, for example, an accelerator pedal sensor 25 in FIG. 2 described later. Again 104
Is load detecting means for detecting the load amount of the internal combustion engine, and corresponds to, for example, the load sensor 26 in FIG. 2 described later. The throttle valve opening of the internal combustion engine, the intake air amount, and the like can be used as the load amount.

Further, the control means 105 stops the operation of the constant speed traveling device 100 when the vehicle speed is equal to or lower than a predetermined value and the accelerator pedal is not depressed but the load amount is equal to or higher than the predetermined value. At the same time, the output of the internal combustion engine 101 is controlled so as to be limited. The control means 104 corresponds to, for example, the control means 22 and the switching means 21 shown in FIG.

As a method of stopping the operation of the constant speed traveling device 100 as described above, for example, as shown in FIG. 2 described later, the power source is forcibly cut off by the switching means 21, or the output terminal of the controller 9 and the actuator are connected. Control unit 13
It is possible to use a method in which the point of the connection point X with and is cut off or grounded.

Further, as a method of limiting the output of the internal combustion engine 101 as described above, for example, as shown in FIG. 2 described later, a method of setting a predetermined upper limit value for the fuel supply amount of the fuel supply device 27 or a fuel cutoff rotation speed. Is set to a value lower than the normal value (details will be described later). There is also a method of delaying the ignition timing set by the ignition timing control device from an appropriate value.

[Action]

The constant speed traveling device is used when continuously traveling on a highway or the like at a constant speed. Therefore, the constant speed traveling device is usually set to be operable only at a predetermined set speed (for example, 60 km / h) or higher in accordance with the traveling speed of the highway.

Therefore, it is not necessary to activate the constant-speed traveling state when starting from a stopped state or when traveling at a low speed that is significantly slower than the set speed above.In addition, if the constant-speed traveling device operates in such a state, malfunction may occur. It can be determined that

Also, if the load on the internal combustion engine is large even though the accelerator pedal is not depressed, malfunctions of the constant speed traveling device or a malfunction such as catching on the throttle link system connecting the accelerator pedal and the throttle valve may occur. The throttle valve may be open even though the accelerator pedal is not depressed.

The present invention is based on the above consideration, when the vehicle speed is equal to or lower than a predetermined vehicle speed (for example, 40 km / h) corresponding to an unnecessary area of the constant speed traveling device, and the accelerator pedal is not depressed,
When the load amount of the internal combustion engine is equal to or greater than a predetermined value, the operation of the constant speed traveling device is stopped and the output of the internal combustion engine is controlled.

With the above-mentioned configuration, in the present invention,
If the constant-speed traveling device operates during start-up or low-speed traveling, or if the vehicle does not travel at the desired target speed due to a malfunction of the throttle link system, etc. Since the operation of the high speed traveling device can be stopped and the output of the internal combustion engine can be limited, the controllability can be further improved as compared with the conventional case.

Example of Invention

2 and 3 are diagrams showing an embodiment of the present invention.
FIG. 3 is an overall configuration diagram, and FIG. 3 is a table showing the configuration of an actuator control unit and its operation content.

First, in FIG. 2, a portion constituted by 1 to 18 (17 is described in FIG. 3) is a constant speed traveling device (ASCD).

A battery is connected to the power supply terminal 1 via an ignition switch or a fuse (not shown).
Further, the switching means 21 is turned on when the constant speed traveling device is normally operated (details will be described later). Further, the ASCD relay 3 is excited when the main switch 4 of the ASC is turned on, and its contact is turned on. The battery (not shown) includes the power supply terminal 1, the switching means 21, and the ASCD.
It is connected to the operation circuit 6 via the contact of the relay, and is also connected to the controller 9 via the inhibit switch 11 and the brake switch 12. Therefore, during the normal operation when the switching means 21 is turned on, when the main switch 4 is turned on, the contact of the ASCD relay 3 is turned on and the power source is connected to the constant speed traveling device, so that the constant speed traveling device operates. It becomes operational. In this state, the main lamp 4
Lights up, indicating that the constant-speed traveling device is operating.

On the other hand, a battery is also connected to the power supply terminal 2 via an ignition switch or a fuse (not shown). The power supply terminal 2 is connected to a controller 9 via a stop lamp switch 7 which is turned on when the brake pedal is depressed, and a stop lamp 8 which is turned on when the switch is turned on is connected. Therefore, when the brake pedal is depressed, the stop lamp switch 7 is turned on, and the information indicating that the brake operation is performed is transmitted to the controller 9.

Next, the operation circuit 6 will be described.

The operation circuit 6 is installed in the steering wheel from the viewpoint of operability, and is connected to the controller 9 via a slip ring, that is, a sliding contact provided in a rotating portion of the steering wheel.
The operation circuit 6 is composed of a set switch, an accelerator switch and a resume switch, one end of each of which is connected to the battery via the ASCD relay 3. The other end of each switch is independently connected to the controller 9.

Next, the functions of the set switch, the accelerator switch and the resume switch of the drive circuit 6 will be described.

First, the set switch is a switch for setting the constant speed running state.For example, if the set switch is temporarily closed while the vehicle is traveling at 60 km / h, then the constant speed running at 60 km / h continues. To do. If the set switch is further closed in such a constant speed traveling state, the vehicle speed is gradually reduced by the internal combustion engine brake. That is, the set switch also has a function as a coast switch.

Next, the accelerator switch has an accelerator function.If the accelerator switch is kept closed in the constant-speed running state, the vehicle speed is gradually increased.After that, when the accelerator switch is opened, the vehicle speed at the time of opening is set to the constant value. Run at high speed.

Also, the resume switch is operated when the constant speed running state is temporarily canceled by the brake operation etc. after setting the constant speed running state at the above-mentioned constant speed 60 km, and the vehicle speed is reduced to the above constant speed 60 km or less. Then, the vehicle speed is sequentially increased and is reset to the speed of the previous constant speed traveling stored in the storage means described later, that is, the constant speed traveling state at time 60 km in the above example.

Next, the vehicle speed sensor 10 is connected to the controller 9, and the speed information according to the traveling speed of the vehicle is sent to the controller 9 by the controller 9.
Send to. For example, the vehicle speed sensor 10 has a built-in switching means that opens and closes according to the traveling speed of the vehicle, and as the traveling speed of the vehicle increases, the opening and closing operation of the switching means becomes faster. An intermittent signal is output as speed information.

Further, as described above, the power supply terminal 1 is connected to the controller 9 from the ASCD relay via the inhibit switch 11 and the brake switch 12. The inhibit switch 11 is turned off when the shift lever of the automatic transmission is set to the parking range P or the neutral range N, and is turned on when the range is other than that (drive D and reverse R). It is a contact point. Further, the brake switch 12, which is a normally closed contact, is turned off when the brake pedal is depressed.

When at least one of the inhibit switch 11 and the brake switch 12 is turned off, the constant speed traveling control by the controller 9 is released.

Next, the controller 9 will be described.

The controller 9 is a microcomputer that executes various control processes relating to constant speed traveling, a storage unit for storing information regarding constant speed traveling, and a digital circuit for calculating the vehicle speed based on the speed information from the vehicle speed sensor 10. It incorporates a vehicle speed discriminating unit and the like, and outputs various control signals based on each information from the operation circuit 6 and the vehicle speed sensor 10. For example, when it is determined that the set switch is operated based on the information from the operation circuit 6, the vehicle speed sensor
Based on the speed information from 10, the vehicle speed at the time when the set switch is operated is calculated and stored in the storage means, and based on the calculated vehicle speed, a transition to a constant speed traveling state at the vehicle speed is performed. Output a control signal. Also,
When the controller 9 determines that the accelerator switch has been operated, the controller 9 outputs a control signal to sequentially increase the traveling speed of the constant speed traveling at a predetermined rate. Further, when it is determined that the resume switch has been operated during traveling after the constant-speed traveling state has been temporarily released by the operation of the brake switch 12 accompanying the brake operation, the speed stored in the storage means is determined. At the same time as reading the information, a control signal for returning to the original constant speed traveling state is output based on the speed information.

Actuator control part by each control signal as above
Control 13

Next, the actuator controller 13 will be described with reference to FIG.

As shown in FIG. 3 (A), the actuator controller 13
Negative pressure pump 14, air valve 15 and release valve
It consists of 16.

Then, according to the control signal given from the controller 9 as described above, as shown in FIG.
4. By controlling the operation of the air valve 15 and the release valve 16, a desired negative pressure is generated, and the actuator 17 (negative pressure valve) is operated by the negative pressure.

As shown in FIG. 3B, when the constant speed traveling control is not operated, the negative pressure pump 14 is stopped and the air valve 15 is stopped.
The release valve 16 and the release valve 16 are always "opened" so that the pressure inside the actuator 17 becomes atmospheric pressure, and the operation amount of the actuator 17 becomes zero. Further, during the operation of the constant speed traveling control, the operation of the negative pressure pump 14 is controlled according to the relationship between the target speed and the actual vehicle speed, and the air valve 15 and the release valve 16 are controlled.
Is controlled to be opened and closed, and thereby the operation amount of the actuator 17 is controlled.

The actuator 17 is connected to a throttle valve (not shown) of an internal combustion engine by an ASCD wire.
The throttle valve opening is adjusted according to the operation amount of the vehicle speed, thereby controlling the vehicle speed to the desired target speed as described above.

Further, in FIG. 2, when the constant speed traveling device is operating, the cruise lamp 18 is turned on by a signal from the controller 9 to indicate that the vehicle is in the constant speed traveling state.

Next, the control means including the switching means 21 which characterizes the present invention will be described.

In FIG. 2, reference numeral 24 is a vehicle speed sensor for detecting the vehicle speed, and for example, the same vehicle speed sensor 10 as described above can be used. It can also be shared with the vehicle speed sensor 10.

Reference numeral 25 denotes an accelerator pedal sensor that detects that the accelerator pedal is depressed, and for example, a switch that is turned on when the accelerator pedal is depressed can be used.

Reference numeral 26 denotes a load sensor that detects the load amount of the internal combustion engine, and for example, a sensor that detects the throttle valve opening of the internal combustion engine or a sensor that detects the intake air amount can be used.

Each of the above-mentioned 24-26 sensors may be provided with an independent sensor in particular, but a device provided as a sensor such as a fuel injection control device for an internal combustion engine may be shared for the device of the present invention. Good.

Next, the control means 22 is composed of a dedicated analog circuit or a dedicated digital circuit, or a microcomputer (can be shared with a computer for a fuel injection control device or the like), and inputs the signals of the respective means of the above 24 to 26. A discriminating operation as described later is performed based on the detection results, and when a predetermined state is discriminated, the ASCD cut signal 23 and the fuel limit command signal 28 are output.

The switching means 21 is a transistor switching circuit, a relay, or the like, and is normally turned on, but turned off when the ASCD cut signal 23 is applied.

When the switching signal 21 is turned off as described above, the power to the constant speed traveling device such as the controller 9 is shut off as in the case where the main switch 4 is turned off, so that the operation of the constant speed traveling device is surely performed. Stopped.

Note that instead of the switching means 21, the controller 9
It is also possible to use switching means for cutting off the output terminal of the actuator control section 13, that is, the connection point X between the actuator control section 13 and the actuator control section 13 or for grounding.

In addition to stopping the operation of the constant speed traveling device as described above, the fuel supply device 27 is also activated by the fuel limit command signal 28.
The output of the internal combustion engine can be limited by limiting the fuel supply amount of the fuel injection control device or the electronically controlled carburetor or by reducing the fuel cutoff rotation speed. The details of each control described above will be described later.

Next, the state discrimination calculation in the control means 22 will be described.

FIG. 4 is a flow chart showing an embodiment of the state discrimination calculation when the control means 22 is constituted by a microcomputer. This flow is repeatedly calculated every predetermined time.

In FIG. 4, at P ₁ , the vehicle speed is a predetermined value (for example, 40 km /
h) Determine whether or not

Next, it is determined at P _2, whether the accelerator pedal is depressed.

Then, the P _3, load (throttle valve opening or the intake air amount) is equal to or greater than a predetermined value. It should be noted that this predetermined value is set, for example, to a value that is slightly larger than the load amount in a state in which the accelerator pedal is not depressed during normal operation, that is, in the fully closed state (idle opening degree) of the throttle valve.

If all of the above P _{1 to} P ₃ are YES, that is, if the vehicle speed is less than or equal to a predetermined value, and the accelerator pedal is not operated, but the load amount is greater than the predetermined value, the fuel at P ₄ The limit command signal 28 is output to limit the output of the internal combustion engine, and the ASCD cut signal (ASCD cut signal 23 in FIG. 2) is output at P ₅ . This signal turns off the switching means 21 of FIG. 2 as described above, and the operation of the constant speed traveling device is stopped.

Next, a method for limiting the output of the internal combustion engine in said P _4.

As a method of limiting the output of the internal combustion engine, for example, a method of setting a predetermined upper limit value for the fuel supply amount, a fuel cutoff rotation speed (a rotation speed at which the fuel is cut off when the rotation speed is reached) is set to a value lower than a normal value. There is a way to set.

First, a method of setting a predetermined upper limit value for the fuel supply amount is performed by setting the upper limit value of the fuel supply amount to, for example, 30 times the normal maximum fuel supply amount.
Even if the throttle valve is opened widely and the intake air amount increases, the fuel is not supplied to the value above the upper limit value. By doing this, even if the throttle valve is fully opened, only a small amount of fuel will be supplied.
The air-fuel mixture becomes lean and lean combustion occurs, resulting in a significant reduction in engine output, making rapid acceleration impossible. In this state, the engine is in a bad condition. There is no risk that the engine will stop if the above upper limit is set appropriately.

In order to implement this method, for example, when the fuel supply device 27 is a fuel injection control device, the fuel injection pulse width Tp may be set to an upper limit value that is lower than the maximum value during normal operation. Further, in the case of an electronically controlled vaporizer, the main system fuel passage or mixer passage of the vaporizer may be configured to be blocked by an electromagnetic valve. In this case, since the slow system and the power system can be operated, the vehicle can travel at a low speed, and the vehicle travel is never disabled.

Next, the method of setting the fuel cutoff rotation speed to a value lower than the normal value is that the fuel cutoff rotation speed is significantly lower than the value at the normal time (a value determined according to the type of internal combustion engine, for example, 7000 rpm). It is set to a value (eg 2500 rpm). With this configuration, the throttle valve is opened to increase the rotation speed, and the fuel is cut off immediately when the set value is reached. Therefore, the rotation does not increase above the value.

Next, FIG. 5 is a flowchart showing a calculation for realizing the above method when the fuel supply device 27 is a fuel injection control device.

In FIG. 5, first, at P ₁₀ , the basic injection pulse width Tp
Read. The value of this Tp is the intake air amount Q and the rotation speed N.
Therefore, it is also obtained by calculation according to the mathematical expression of Tp = K · Q / N (K is a constant). The actual injection amount Ti is
The above Tp is variously corrected as described later.

Next, at P ₁₁ , various correction coefficients COEF are read. Examples of this correction coefficient include correction coefficients for low water temperature increase, starting increase and post-start increase, idle increase, acceleration / deceleration correction, high water temperature increase, and the like.

Next, at P ₁₂ , the air-fuel ratio correction coefficient α is read. The air-fuel ratio correction coefficient α is a correction coefficient for feedback control so that the air-fuel ratio of the air-fuel mixture is maintained at a predetermined value.

Next, at P ₁₃ , the voltage correction amount Ts corresponding to the fluctuation of the battery voltage is read.

Then, the P _14, calculates the fuel injection amount Ti from the read value above the P ₁₀ to P _13.

The above Ti is calculated according to the following equation (1), for example.

Ti = Tp × COEF × α + Ts ... (1) Next, the P _15, the rotational speed N of the internal combustion engine is of the Figure 4 P
_It is judged whether or not the fuel cutoff rotational speed NC = D set in ₄ (set in the fuel injection control device by the fuel limit command signal) or more, and if YES, go to P ₁₆ and set the FC flag, then P _It goes to ₁₇ and outputs the fuel injection amount Ti with 0 (that is, fuel cutoff).

If NO at P _15, go to P _18, the rotational speed N is determined whether the recovery rotational speed NR (resume stop and fuel supply to the fuel cutoff When rotational speed becomes less value) or more .

If NO in P ₁₈ , that is, if the rotation speed falls below the recovery rotation speed NR, clear the FC flag in P ₂₀ , then go to P ₂₁ and set the value of the fuel injection amount Ti calculated in P ₁₄ above. Output as is.

If YES in P ₁₈ , go to P ₁₉ .

In the case of SET in P ₁₉ , that is, in the fuel cutoff state in which the FC flag is set, go to P ₁₇ and continue the fuel cutoff state.

In case of CLR at P ₁₉ , the fuel injection amount goes through the route of P ₂₀ , P ₂₁
The value of Ti is output as it is.

As described above, in the flowchart of FIG. 5, when the rotational speed of the internal combustion engine reaches NC, fuel cutoff is performed, so
It can be controlled so that the rotation speed does not exceed NC. Therefore, for example, even if a failure occurs such that the throttle link system that adjusts the throttle valve opening is caught and the throttle valve opens, it is possible to control so that the rotation speed does not exceed NC. I can. Therefore, if the above-mentioned value of NC = D is set to a low value that does not cause a problem in driving, stable control can always be performed.

〔The invention's effect〕

As described above, in the present invention, the vehicle speed is equal to or lower than the predetermined vehicle speed corresponding to the unnecessary area of the constant speed traveling device,
When the accelerator pedal is not depressed and the load on the internal combustion engine is equal to or greater than a predetermined value, the operation of the constant speed traveling device is stopped and the output of the internal combustion engine is limited. Therefore, if the constant-speed traveling device operates during start-up or low-speed traveling, or if the vehicle does not travel at the desired target speed due to a failure of the throttle link system, etc. In addition, since the operation of the constant speed traveling device can be stopped and the output of the internal combustion engine can be limited, an excellent effect that the controllability can be further improved as compared with the conventional case can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing the function of the present invention, FIGS. 2 and 3 are drawings showing an embodiment of the present invention, and FIGS. 4 and 5 are executions of a flow chart showing the contents of calculation in the above embodiment. It is an example figure. <Explanation of symbols> 1, 2 ... Power supply terminal, 3 ... ASCD relay 4 ... Main switch, 5 ... Main lamp 6 ... Operation circuit 7 ... Stop lamp switch 8 ... Stop lamp, 9 ... Controller 10 …… Vehicle speed sensor 11 …… Inhibit switch 12 …… Brake switch 13 …… Actuator controller 14 …… Negative pressure pump, 15 …… Air valve 16 …… Release valve, 17 …… Actuator 18 …… Cruise lamp, 21… … Switching means 22 …… Control means 23 …… ASCD cut signal 24 …… Vehicle speed sensor 25 …… Accelerator pedal sensor 26 …… Load sensor, 27 …… Fuel supply device 28 …… Fuel limit command signal 100 …… Constant speed running Device, 101 ... Internal combustion engine 102 ... Vehicle speed detection means 103 ... Accelerator pedal detection means 104 ... Load detection means, 105 ... Control means

Claims (1)

[Claims] 1. A vehicle equipped with a constant speed traveling device for automatically traveling at a predetermined target speed by feedback-controlling a throttle valve opening of an internal combustion engine so that an actual vehicle speed matches a target vehicle speed. In the control device, vehicle speed detection means for detecting the vehicle speed, accelerator pedal detection means for detecting whether or not the accelerator pedal is depressed, load detection means for detecting the load amount of the internal combustion engine, and detection results of the above means Based on the vehicle speed is below a predetermined value and the accelerator pedal is not depressed when the load amount is more than a predetermined value, the control means for stopping the operation of the constant speed traveling device and limiting the output of the internal combustion engine, Control device for a vehicle equipped with.