JPH04274933A - Constant speed running device for vehicle - Google Patents

Abstract

PURPOSE:To prevent the dispersion in acceleration and improve the drivability by accelerating it at constant acceleration in case of returning from the constant run release condition to constant speed run. CONSTITUTION:A desired output torque operating means 5 operates the output of an engine so that it may be at constant speed from the difference between the speed of a vehicle detected by a vehicle speed detecting means 1 and the target speed and the resistance in running operated by a running resistance operating means 4, and a throttle aperture operating means 6 operates the throttle aperture for materializing this output, and a throttle aperture control means 7 controls the throttle into this throttle aperture.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant speed traveling device for a vehicle, and more particularly, the present invention relates to a constant speed traveling device for a vehicle, and more particularly, after decelerating by canceling constant speed traveling at a preset target vehicle speed, the vehicle is decelerated by performing a return operation. The present invention relates to a constant-speed traveling device for a vehicle that controls the vehicle to return to a target vehicle speed and perform constant-speed traveling.

0002

[Prior Art] Constant speed driving device (ASCD)
tic Speed ControlDevice
), when the driver presses the accelerator pedal to accelerate the vehicle to the desired speed and then operates the vehicle speed setting switch for constant speed driving, the vehicle speed at that time is set as the vehicle speed for constant speed driving, and from then on, the actual vehicle speed is set. The throttle opening is adjusted so that the deviation between the set speed and the set vehicle speed is zero, and the vehicle is automatically controlled to run at a constant speed. Such a constant speed traveling device is disclosed, for example, in Japanese Patent Application Laid-Open No. 59-58134, and is a very convenient device since it is not necessary to constantly press the accelerator pedal when driving at a constant speed on a highway. .

[0003]Furthermore, such a constant speed driving device cancels the constant speed driving operation by the driver's cancel operation, and when the vehicle speed becomes lower than the set vehicle speed which is the target vehicle speed,
When you operate the return switch, that is, the RES switch,
The vehicle is re-accelerated, returns to the previously set target vehicle speed, and continues to drive at a constant speed.

0004

[Problems to be Solved by the Invention] In the conventional constant speed traveling device as described above, when constant speed traveling is canceled by a cancel operation and the vehicle speed becomes lower than the set vehicle speed, a return switch is operated to return to the constant speed traveling. When reaccelerating to return to high speed driving, when the return switch is operated, negative pressure control is performed on the actuator to open the throttle to return to the original set vehicle speed, but the moment the return switch is operated,
If a signal is output to open the throttle so that the throttle opening is set in advance, there is a problem in that even if the same opening signal is output, the acceleration of the vehicle will differ depending on the operating state of the engine. There is a problem in that it is necessary to tune the way the throttle is opened so that the acceleration falls within a predetermined range even in this state.

[0005] The present invention has been made in view of the above, and
The purpose is to provide a constant speed driving device for a vehicle that accelerates at a constant acceleration when returning to constant speed driving from a constant speed driving state, prevents variations in acceleration, and improves drivability. It is in.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the constant speed traveling device of the present invention, as shown in FIG. 1, decelerates the vehicle by canceling constant speed traveling at a preset target vehicle speed. A constant speed traveling device for a vehicle that controls the vehicle to return to the target vehicle speed and perform constant speed traveling by performing a return operation after that, comprises a vehicle speed detecting means 1 for detecting the speed of the vehicle, and a vehicle speed detected by the vehicle. A speed difference calculating means 2 for calculating the difference between the speed and the target vehicle speed, a driving state detecting means 3 for detecting the operating state of the engine, a running resistance calculating means 4 for calculating the running resistance of the vehicle, and a speed difference calculating means 2 for calculating the difference between the speed difference and the target vehicle speed. Output torque calculation means 5 that calculates the output torque of the engine so that the acceleration becomes constant from running resistance, Throttle opening calculation means 6 that calculates the throttle opening to realize this calculated output torque, and this calculation. The gist of the present invention is to have a throttle opening degree control means 7 for controlling the throttle to a throttle opening degree determined by the throttle opening degree.

[0007]

[Operation] The constant speed traveling device of the present invention calculates the output torque of the engine to achieve a constant acceleration from the difference between the vehicle speed and the target vehicle speed and the traveling resistance, and adjusts the throttle opening to achieve this output torque. is calculated and the throttle is controlled to this throttle opening degree.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a constant speed traveling device for a vehicle according to an embodiment of the present invention. The constant speed traveling device shown in the figure includes a vehicle speed detecting means 1 that detects the traveling speed of the vehicle, and a speed difference calculating means 2 that calculates the difference between the detected vehicle speed and the set speed when traveling at a constant speed. , a driving state detecting means 3 for detecting the driving state of the engine, a running resistance calculating means 4 for calculating the running resistance of the vehicle, and a speed difference calculated by the speed difference calculating means 2 and a vehicle calculated by the running resistance calculating means. an output torque calculation means 5 that calculates the output torque of the engine so that the acceleration becomes constant when the acceleration is from the running resistance to the set speed; and a throttle opening that calculates the throttle opening to realize the calculated output torque. It is composed of a calculation means 6 and a throttle opening control means 7 that controls the throttle to the calculated throttle opening.

The operation of the vehicle constant speed traveling device shown in FIG. 1 is as follows.
This will be described later with reference to FIG. 3, which shows a specific configuration of this constant speed traveling device, and the flowchart shown in FIG.

FIG. 2 is a block diagram showing the configuration of a constant speed traveling device for a vehicle according to another embodiment of the present invention. The constant speed traveling device shown in the figure is different from the constant speed traveling device shown in FIG. 1 in that an acceleration calculating means 8 is newly provided between the desired output torque calculating means 5 and the throttle opening calculating means 6. It is. This newly provided acceleration calculation means 8 calculates the actual acceleration of the vehicle.

FIG. 3 is a configuration diagram of a constant speed traveling device embodying each of the embodiments shown in FIGS. 1 and 2 described above. In the figure, 11 is a crank angle sensor that generates a signal for each unit angle of the crank and for each reference position, 12 is a throttle opening sensor that detects the throttle opening θR by the output voltage of a potentiometer, and 13 is a sensor for the current vehicle. A vehicle speed sensor 14 that detects the running speed is a return switch that is a so-called RES switch for returning to constant speed running.

Detection signals from the crank angle sensor 11, throttle opening sensor 12, and vehicle speed sensor 13 and output signals from the return switch 14 are supplied to the CPU 15, which executes the processing shown in FIGS. 4 and 5, which will be described later. A target throttle valve opening that provides the amount of air necessary to output the target torque to maintain the set vehicle speed is calculated, and this is output to the servo drive circuit 16 to control the amount of air. Reference numeral 17 denotes a ROM that stores various data necessary for calculations by the CPU 15, such as an engine output torque table 21 shown in the figure.

Further, the servo drive circuit 16 is connected to the intake passage 18.
The actual throttle valve opening θR detected by the throttle opening sensor 12 that detects the opening of the throttle valve 19 provided in The servo motor 20 connected to the throttle valve 19 is driven and controlled according to the deviation.

Next, the operation will be explained with reference to the flowcharts shown in FIGS. 4 and 5.

Note that FIGS. 4 and 5 are flowcharts of processes corresponding to the operations of the embodiments shown in FIGS. 1 and 2, respectively. Further, although the processes in FIGS. 4 and 5 show the processes performed by the CPU 15, each process is executed at regular intervals of, for example, every 4 msec.

The process shown in FIG. 4 will be explained. First, the output of the return switch 14 is read (step 110). This is because the vehicle speed and engine operating state at the moment this switch is operated are the basis for this process. Then, in the next step 120, the current vehicle speed Vsp at the time the return switch 14 was operated is read from the output value of the vehicle speed sensor 13. Note that steps 110 and 120, the vehicle speed sensor 13, and the return switch 14 constitute the vehicle speed detection means 1 shown in FIG.

In the next step 130, step 120
The difference Evsp between the current vehicle speed Vsp read in and the set vehicle speed VSET when driving at constant speed is calculated. Then, the speed difference Evsp calculated in step 130 is "0".
It is checked whether or not (step 140). If the speed difference is "0", this process ends, but if it is other than "0", the process proceeds to step 150. In addition, step 1
30 and 140 constitute the speed difference calculation means 2.

In step 150, the current engine speed Ne is read. The engine speed Ne is calculated based on the signal from the crank angle sensor 11. In the next step 160, the current throttle opening θR is read from the output value of the throttle opening sensor 12. Then, the current output torque is calculated based on the engine speed Ne and throttle opening θR read in steps 150 and 160 (step 170). This calculation is performed based on the engine output torque map shown in Fig. 6.
It is performed by looping up with R and Ne. Note that steps 150, 160, and 170, the crank angle sensor 11, and the throttle opening sensor 12 constitute the driving state detecting means 3.

In the next step 180, step 110
The current running resistance RL is calculated based on the engine operating state and vehicle speed determined in steps 170 to 170. This running resistance RL takes a different value depending on the vehicle speed, weight, etc., and the difference between the output torque and the running resistance is fed back as the vehicle speed. Note that step 180 constitutes the running resistance calculation means 4.

More specifically, when the return switch 14 is operated, the basic data for how to open the throttle when returning to the original set vehicle speed during constant speed driving is based on the current operating state of the engine. Calculate the running resistance of the vehicle. In calculating the running resistance RL, model the engine system, torque converter and gear system of the applicable model, find the torque TL output from the torque converter side, and calculate the driving force FR actually consumed for vehicle movement. This is the running resistance.

Further, the driving force FR is the engine output torque Te obtained from the engine torque table based on the current throttle opening θR and the engine speed Ne.
, gear ratio GM, gear efficiency ETM, final gear ratio GN
, final gear efficiency ETN, effective tire radius r, and torque ratio t of the torque converter.

FR=Te・t・GM・ETN・GN・ET
N/r...(1) The estimated running resistance RL is determined by the following formula from the driving force FR determined by the above formula and the acceleration α calculated from the speed change of the vehicle.

RL = FR −α·W/g

...(2) However, W is the vehicle weight (Kgf).

Then, the speed difference EVsp obtained in step 130 and the running resistance RL obtained in step 180
Based on this, the engine output torque TN required to return from the current vehicle speed to the set vehicle speed is calculated (step 190).

As described above, when the running resistance RL is determined, the output torque TN can be calculated by transforming the above equation (2) as follows, using α as a parameter to obtain the target driving force FN.

[0027] FR=RL +α・W/g

(3) The target output torque TN can be calculated from the target driving force FN determined in this way. When this output torque is obtained, constant speed running is performed at the desired set speed. Note that step 190 is performed by the desired output torque calculation means 5.
This is what makes up the .

In the next step 200, step 190
Based on the desired output torque value obtained in , the throttle opening degree θo required to generate the output torque is calculated. This calculation is performed, for example, by looking up the engine output torque TN and engine rotational speed Ne based on the engine output torque map shown in FIG.

In the next step 210, step 200
Control is performed on the throttle so that the throttle opening degree is calculated by . This step 210 constitutes the throttle opening control means 7.

Next, the processing shown in FIG. 5 will be explained. The process of FIG. 5 includes steps 120 and 1 in the process of FIG.
The difference is that steps 310 and 320 are provided between the steps 30 and 30.

In this newly added step 310, the actual acceleration αR of the vehicle is calculated based on the vehicle speed Vsp read in the step 120, and the process proceeds to the next step 3.
At step 20, it is checked whether this acceleration αR is within a predetermined acceleration range (α1<αR<α2). Then, if it is within this range, the process returns to step 120, and only if it is outside the range, the process proceeds to step 130 and subsequent steps described above. Note that steps 310 and 320 constitute the throttle opening calculation means 6.

[0032]

[Effects of the Invention] As explained above, according to the present invention,
Calculates the engine output torque to achieve a constant acceleration from the difference between the vehicle speed and the target vehicle speed and the running resistance, calculates the throttle opening to achieve this output torque, and controls the throttle to this throttle opening. Therefore, until the vehicle speed returns to the set vehicle speed and settles down to constant speed driving, acceleration is performed at a constant acceleration, and it is possible to prevent deterioration of drivability due to variations in acceleration.

[Brief explanation of the drawing]

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

FIG. 2 is a block diagram showing the configuration of a constant speed traveling device for a vehicle according to another embodiment of the present invention.

FIG. 3 is a configuration diagram of a constant speed traveling device embodying each of the embodiments shown in FIGS. 1 and 2. FIG.

4 is a flowchart showing a process corresponding to the constant speed traveling device of FIG. 1 using the constant speed traveling device of FIG. 3; FIG.

5 is a flowchart showing processing corresponding to the constant speed traveling device of FIG. 2 using the constant speed traveling device of FIG. 3; FIG.

FIG. 6 is a graph showing an engine torque table used in the constant speed traveling device of FIG. 3;

[Explanation of symbols]

1 Vehicle speed detection means 2 Speed difference calculation means 3 Operating state detection means 4 Running resistance calculation means 5 Desired output torque calculation means 6 Throttle opening calculation means 7 Throttle opening control means

Claims (1)

[Claims] [Claim 1] A constant speed vehicle that is controlled so that after decelerating by canceling constant speed driving at a preset target vehicle speed, the vehicle returns to the target vehicle speed and performs constant speed driving by performing a return operation. The traveling device includes vehicle speed detection means for detecting the speed of the vehicle, speed difference calculation means for calculating the difference between the detected vehicle speed and the target vehicle speed, and driving state detection means for detecting the operating state of the engine. a running resistance calculating means for calculating the running resistance of the vehicle; an output torque calculating means for calculating the output torque of the engine so as to achieve a constant acceleration from the speed difference and the running resistance; and realizing the calculated output torque. 1. A constant speed traveling device for a vehicle, comprising: a throttle opening degree calculation means for calculating a throttle opening degree; and a throttle opening degree control means for controlling the throttle to the calculated throttle opening degree.