JPS63219480A - Constant speed running device for automobile - Google Patents

Abstract

PURPOSE:To prevent the variation of transmission ratio against the driver's will and to improve the handling property by composing the system regulate the transmission ratio variation by a transmission ratio control device of the steering system, which is resulting from the actual car speed, when a constant speed control device is in the operational condition. CONSTITUTION:When the car speed setting instruction is given by a car speed setting device 3, the car speed detected by a car speed sensor 4 is made as an object car speed in a constant speed control device 1, and the output of an engine 6 is controlled through an actuator driving circuit 5 to maintain the object car speed. Furthermore, a control amount as to the transmission ratio responding to the actual car speed by the car speed sensor 4 and the handle steering angle by a handle steering angle sensor 7 is computed in a transmission ratio control device 2, and a transmission ratio variable mechanism 8 furnished in the steering system is controlled. However, when the constant speed control operation condition is detected in this case, the transmission ratio control by the transmission ratio control device 2 depending on the actual car speed is regulated by a regulating device 9.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a constant speed traveling device for an automobile.

(Prior Art) A constant speed traveling device that automatically maintains the vehicle speed of an automobile at a speed set by the driver is known (see, for example, Japanese Utility Model Application No. 57-184228). In other words, in a normal constant speed traveling device, when the vehicle speed reaches the desired IJt speed, the driver sets the vehicle speed and then compares the set vehicle speed with the actual vehicle speed and sets the throttle valve to the actual vehicle speed. This is to control the vehicle speed so that the driver's accelerator operation is no longer reflected in the vehicle speed.

Furthermore, a transmission ratio control device that changes the ratio of the wheel steering angle to the steering wheel steering angle in accordance with the vehicle speed is also generally known (see, for example, Japanese Patent Application Laid-Open No. 58-224852). In other words, this device controls the transmission ratio (handle steering angle/wheel steering angle) to increase as the i1T speed increases, and for a constant steering angle, the wheel steering angle is small at high speeds and large at low speeds. This improves straight-line stability at high speeds, while enabling agile direction changes at low speeds.

(Problems to be Solved by the Invention) The present invention attempts to solve the problems when a transmission ratio control device n is incorporated into an automobile having the above-mentioned constant speed traveling device.

In other words, when the constant speed driving device is activated, although the vehicle speed is controlled to be the set vehicle speed, in reality, due to changes in road surface conditions, etc., the actual vehicle speed may vary over a relatively wide range around the set vehicle speed. do. Therefore, as the actual vehicle speed changes, the ratio of the wheel steering angle to the steering wheel angle is automatically changed by the transmission ratio control device based on a preset characteristic.

On the other hand, if the driver operates the accelerator himself, he can empirically recognize the actual vehicle speed and the amount of wheel turning relative to the steering amount, that is, the transmission ratio, based on that operation, but when driving at a constant speed, Such recognition cannot be made if the device is activated. Therefore, the driver tries to obtain the above-mentioned transmission ratio at the vehicle speed set by the constant-speed traveling device, but there is a problem in that the transmission ratio changes due to fluctuations in the actual vehicle speed, making it difficult to drive.

(Means for Solving the Problems) As a means for solving the above problems, the present invention provides vehicle speed setting means for constant speed driving, and constant speed control means for controlling engine output so as to achieve the set vehicle speed. a control means, a transmission ratio control means for changing the transmission ratio of the steering system according to the driving state of the vehicle, and a transmission ratio control means for detecting the operating state of the constant speed control means and changing the transmission ratio due to fluctuations in the actual vehicle speed. The present invention provides a constant speed driving device for an automobile, which is equipped with a regulating means for regulating changes in transmission ratio.

(Function) In the above constant speed traveling device, even if the actual vehicle speed fluctuates regardless of the operation of the constant speed control means, fluctuations in the transmission ratio due to fluctuations are suppressed, so the actual amount of turning of the wheels due to steering wheel operation is suppressed. The deviation between the amount of steering and the amount of steering intended by the driver is reduced.

(Effects of the Invention) Therefore, according to the present invention, since the operating state of the constant speed control means is detected and the transmission ratio change caused by the transmission ratio control means caused by fluctuations in the actual vehicle speed is regulated, the driver's It is possible to prevent unexpected changes in the transmission ratio and improve the maneuverability of the vehicle.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration of a constant speed traveling device for an automobile. In other words, this constant speed traveling device.

The vehicle includes a control means 1 for driving at a constant speed, and a transmission ratio control means 2 for controlling the transmission ratio R of the steering system (handle steering angle θH/wheel steering angle θ). The constant speed control means 1 receives the setting by the vehicle speed setting means 3 and sends an output control signal to the engine 6 via the actuator drive circuit 5 so that the vehicle travels at a constant speed at the vehicle speed detected by the vehicle speed sensor 4 at that time. give. On the other hand, the transmission ratio control means 2 receives the actual vehicle speed signal from the vehicle speed sensor 4 and the steering wheel steering angle eH signal from the steering wheel angle sensor 7, and determines the transmission ratio R according to the vehicle speed ■ and the steering wheel angle OH. 15. Calculates the control amount and sends a control signal to the variable transmission ratio mechanism 8 provided in the steering system.
At the same time, a regulation signal for transmission ratio control is received from the constant speed control means 1 via the regulation means 9. That is, regulatory means 9
detects that the constant speed control means 1 is in operation of constant speed control, and restricts the transmission ratio control means 2 to control the transmission ratio based on the actual vehicle speed V (stops the transmission ratio control based on the actual vehicle speed V).

Alternatively, a signal Lp is generated to change the control characteristic in the direction of reducing the amount of change in the transmission ratio with respect to a change in the actual 11f speed V.

Now, the specific configuration of the constant speed control system is shown in FIG.

That is, the ignition switch 11 from the power supply IO
A constant speed control means 1 is connected to the current supply circuit via a main switch 12. This constant speed control means l is
Signals from the acceleration switch 13, deceleration switch 14 and return switch 15 as vehicle speed setting means 3; signals from the clutch switch 16 and brake switch 17 as temporary release means for temporarily canceling constant speed control;
and above 11 [receives a signal from the speed sensor 4, and
A signal is output to the actuator drive circuit 5 and the regulating means 9.

In the second case, the acceleration switch 13 is used to initialize the vehicle speed and set the acceleration. In other words, the constant speed control means l is
The vehicle speed detected by the vehicle speed sensor 4 is, for example, 40~look
m/h range, turn on/off from the acceleration switch 13.
When the off signal is input, the vehicle speed at the time of off is set as the vehicle speed ■S at which constant speed driving is to be performed, and the acceleration switch 13 is
When the ON signal is continuously outputted from OFF, the set vehicle speed Vs is increased during that time, and the vehicle is driven at a constant speed at the set vehicle speed Vs at the time of OFF. The deceleration switch 14 is used when decelerating the vehicle while traveling at a constant speed, and when it is turned on, the set vehicle speed Vs decreases. Return switch 15
is a release operation other than the OFF operation of the main switch 12, that is, when constant speed driving control is canceled by the clutch switch 16, which outputs a release signal when the clutch is disengaged, or the brake switch 17, which outputs a release signal when the brake is applied. The constant speed control means 1 receives an ON signal from the return switch 15 and sets the set vehicle speed Vs before release.
Performs return control to

The actuator drive circuit 5 receives a signal from the constant speed control means 1 to maintain, accelerate, decelerate, or return the vehicle speed and controls the throttle valve of the engine 6 to reach the corresponding vehicle speed. (the accelerator control system is released), and upon receiving a release signal from the constant speed control means 1, control of the throttle valve is released.

When the constant speed control means 1 outputs a signal to the actuator drive circuit 5 to maintain, accelerate, decelerate or restore the vehicle speed, it outputs a signal to the regulating means 9 indicating that the constant speed control is in progress and the set vehicle speed Vs. Output a signal.

On the other hand, the specific configuration of the variable transmission mechanism and its control system is shown in FIGS. 3 and 4.

That is, in FIG. 3, 21 is centered on the handle shaft 2.
2 is a fixed steering system handle, and the other end of the handle shaft 22 is a variable transmission mechanism 8 and an intermediate shaft 2.
3 to a steering gear device 24, and this gear device 24 connects to a pitman arm 25 and a tie rod 26.
The left and right wheels 28.2 are connected via a link mechanism 27 consisting of
It is connected to 8.

The variable transmission mechanism 8 is shown in FIG.
The input shaft 30 is disposed on the same axis and facing the input shaft 30 .

Then, the gear 31 fixed to the handle shaft 22 and the human J-axis 3
A gear 32 fixed at 0 meshes with the input shaft 30 and the intermediate shaft 2.
A planetary gear mechanism is provided between 3 and 3. The planetary gear mechanism includes a sun gear 33 fixed to an input shaft 30 and an intermediate shaft 2.
3, and both gears 33.3 and 33.3.
A plurality of planetary binions 35 are arranged at equal angular intervals between the binions 35 and a binion carrier 37 that supports each binion 35 via a binion shaft 36 and is externally fitted rotatably to the input shaft 30. Become. A sector gear 38 formed on the binion carrier 37 meshes with a binion 41 fixed to a rotating shaft 40 of the stepping motor 39.

In this case, the operation of the stepping motor 39 rotates the binion carrier 37 and causes the planetary binion 35 to rotate.
When rotated, the amount of rotation from the handle shaft 22 or sun gear 33 to the ring gear 34 and intermediate shaft 23 increases or decreases, and the transmission ratio R changes.

The transmission ratio control means 2 includes a vehicle speed sensor 4 as shown in FIG.
and a control amount calculation unit 42 that calculates a motor control amount for changing the transmission ratio based on the signal from the steering wheel angle sensor 7;
A drive signal output section 43 that outputs a drive signal corresponding to the calculated motor control amount to the stepping motor 39 is provided.

When not receiving a regulation signal from the regulation means 9, that is, when constant speed control is not being performed, the control amount calculating section 42 calculates the motor control amount OH using the vehicle speed ■ and the steering wheel angle oH as variables, When receiving Regulation No. 13 from
In other words, during constant speed control, the set vehicle speed Vs for constant speed driving is taken as a constant, and the steering wheel steering angle oH is used as a variable to control the motor control amount O.
Calculate M. That is, when constant speed control is not being performed, the transmission ratio R increases as the vehicle speed V increases, as shown by the solid line in FIG. 6, and during constant speed control, as shown by the chain line in FIG. ■The value R5 at s is controlled so as not to fluctuate with respect to changes in the actual vehicle speed. Regarding the steering wheel angle oH, the motor control amount between 0 and 0 is basically calculated based on the characteristic that the larger the steering wheel angle θH is, the smaller the transmission ratio is, regardless of whether or not constant speed control is performed.

The basic flow of the above transmission ratio control is shown in Figure 7. First, it is checked whether constant speed control is in progress, and if it is not in constant speed control, the steering wheel angle oH and vehicle speed ■ are read. , based on this θH+V, the motor control amount θg=f (θH, V
) is calculated, and the stepping motor 39 is driven according to the motor control amount θ (steps 51 to Ss). Also, if constant speed control is in progress, read the steering wheel angle θH,
The set vehicle speed Vs is read, and with this Vs as a constant and OH as a variable, the motor control amount θ is set = f<oH, v
s=constant) is calculated and the stepping motor 39 is driven (step Sl + S6 to Ss
, Ss).

The stepping motor 39 is feedback-controlled by detecting the rotation angle of its rotation shaft 40 by a rotation angle sensor 44, as shown in FIG.

Therefore, in this embodiment, as described above, the transmission ratio characteristics are changed depending on the presence or absence of constant speed control, but in addition, the constant speed control is started and canceled, and the regulation of the transmission ratio control is started and canceled. That is, hysteresis is provided in terms of time between the change in the transmission ratio characteristic as shown in FIG. 8, and the change in the transmission ratio characteristic is delayed by a time T in accordance with the set vehicle speed Vs of the constant speed control. In this case, the hysteresis width W (delay time "1" x 2 ) is made narrower as the set vehicle speed VS becomes higher, as shown in FIG.

Therefore, in the second embodiment, when the vehicle speed is not controlled at a constant speed, the transmission ratio R of the steering system changes according to the vehicle speed ■ and the steering angle oH at that time, and the higher the vehicle speed ■, the higher the steering wheel angle oH. , and the smaller the steering wheel steering angle OH, the larger the transmission ratio R becomes.
8, the amount of steering becomes smaller. Then, when the constant speed control is started, the automatic 11 (is controlled to travel at a constant speed at the set vehicle speed VS, but the actual vehicle speed V fluctuates due to changes in road surface conditions, etc.) At this time, the above-mentioned transmission ratio R is the control amount calculation unit 4
Due to the change in the transmission ratio characteristics in step 2, the relationship with the vehicle speed is determined by the set vehicle speed Vs and is not sensitive to changes in the actual vehicle speed. You will be able to operate the steering wheel. Note that even during constant speed control, the transmission ratio changes according to the steering wheel angle θH, but this change in the transmission ratio depending on the steering wheel angle θH is determined by the driver's will, and does not make it difficult to drive the vehicle.

However, since there is hysteresis in terms of time between the start or cancellation of the constant speed control and the change in the transmission ratio characteristics, even if the constant speed control is started or canceled frequently, there will be a delay. The transmission ratio characteristic is not changed until the time T has elapsed, and frequent changes in the transmission ratio characteristic can be prevented and good drivability can be obtained. Also, the above delay time T
Since the lower the set if speed Vs, the greater the difference, when the transmission ratio R is small, the time to delay changing the transmission ratio characteristic becomes longer, and the transmission ratio characteristic can be changed after the driving condition becomes stable.

Regarding the transmission ratio control during constant speed control, in the above embodiment, the transmission ratio did not change in response to changes in the actual vehicle speed, but as shown by the broken line in Fig. 6, various settings for constant speed driving are changed. At the vehicle speed Vs, the transmission ratio control may be performed by individually setting a transmission ratio characteristic in which the amount of change in the transmission ratio R with respect to a change in the actual vehicle speed ■ is small.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, FIG. 1 is a block diagram showing the basic configuration of the embodiment, FIG. 2 is a circuit diagram of a constant speed control system, FIG. 3 is a perspective view of a steering system, and FIG. A configuration diagram showing the relationship between the variable transmission ratio mechanism and its control system, FIG. 5 is a block diagram showing the transmission ratio control system, and FIG. 6 is a characteristic diagram of the transmission ratio control.
Fig. 7 is a flowchart of transmission ratio control, Fig. 8 is a time-related characteristic diagram showing the relationship between constant speed control and changes in transmission ratio characteristics, and Fig. 9
The figure is a characteristic diagram showing the relationship between the width W of the hysteresis shown in FIG. 8 and the vehicle speed. 1... Constant speed control means, 2... Transmission ratio control means, 3... Vehicle speed setting means, 4...
Vehicle speed sensor, 6... Engine, 8...
Variable transmission ratio mechanism, 9...Regulating hand Figure 1, Figure 2

Claims (1)

[Claims] (1) A means for setting the vehicle speed at which the vehicle should run at a constant speed, a constant speed control means for controlling the output of the engine so that the vehicle speed is set by the means, and a ratio of the wheel steering angle to the steering wheel angle of the steering system. transmission ratio control means for changing the transmission ratio according to the driving condition of the vehicle, and regulating means for detecting the operating state of the constant speed control means and regulating changes in the transmission ratio caused by the transmission ratio control means caused by fluctuations in the actual vehicle speed. A constant speed traveling device for an automobile, characterized by comprising: