JP3238588B2 - Inter-vehicle distance control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-vehicle distance control device, and more particularly to an inter-vehicle distance control device comprising an inter-vehicle distance measuring means, a vehicle speed detecting means, a brake control means and the like connected to an ECU.

[0002]

2. Description of the Related Art The cause of rear-end collisions of trucks and general passenger cars that transport long distances is that drivers who fall asleep or drunk driving account for the majority. Under such circumstances, the current inter-vehicle distance between the host vehicle and the preceding vehicle is detected, and when the distance becomes equal to or more than a predetermined distance, the accelerator or brake is automatically controlled to maintain the predetermined inter-vehicle distance. Such an inter-vehicle distance control device has been developed. The device emits laser light toward the vehicle ahead of the own vehicle, receives the part where the laser light hits the reflector on the rear surface of the front vehicle, receives the light, calculates the distance between the vehicles from the time difference, and determines the predetermined distance between the vehicles. The accelerator or the brake is operated depending on whether or not the distance is longer than the distance.

However, in such a conventional inter-vehicle distance control device, the accelerator or the brake is automatically operated irrespective of the driver's intention. There is a problem that it is difficult to remove a sense of incongruity to the driver, for example, the deceleration becomes too large when applied.

On the other hand, an inter-vehicle distance control device is disclosed in Japanese Patent Application Laid-Open No. H05-042862 in which brakes having different braking characteristics are actuated in accordance with the state of the inter-vehicle distance and relative speed in conjunction with the driver's brake operation. It is proposed in the gazette. According to this, when the driver performs the brake operation, a strong brake is instantaneously applied at an early stage, and the stopping distance is shortened.

[0005]

However, the inter-vehicle distance control device described above is intended to stop the own vehicle, and can eliminate a sense of discomfort felt by a driver when adjusting the inter-vehicle distance. It was not something.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an inter-vehicle distance control device capable of smoothly controlling the inter-vehicle distance without causing the driver to feel uncomfortable.

[0007]

In order to achieve the above object, an inter-vehicle distance control device (1) according to the present invention comprises an inter-vehicle distance measuring means, a vehicle speed detecting means and a brake pedal which are operated by an ECU.
In a headway distance control device to which a brake switch, a control switch, a brake control means, and the like that are activated when the brake switch is turned on, the control switch is turned on and the vehicle decelerates at a predetermined deceleration. The speed is increased to a predetermined value, and then the deceleration is maintained for a predetermined time when the brake switch is turned off.
And a deceleration adjusting means for returning the increased deceleration to the original deceleration.

[0008] Further, the inter-vehicle distance control device (2) according to the present invention comprises an inter-vehicle distance measuring means, a vehicle speed detecting means,
In an inter-vehicle distance control device to which a brake switch, a control switch, a brake control means, and the like, which operate when a brake pedal is depressed , the brake switch is turned on while the control switch is turned on and the vehicle is decelerated at a predetermined deceleration. And the deceleration
Gradually increase at a predetermined speed different from the stepping amount of the
It is characterized in that it is provided with deceleration adjusting means for achieving a predetermined maximum deceleration.

The inter-vehicle distance control device (3) according to the present invention includes an inter-vehicle distance measuring means, a vehicle speed detecting means,
In an inter-vehicle distance control device to which a brake switch, a control switch, a brake control means, etc., which is activated when a brake pedal is depressed , the brake switch is turned on from off while the control switch is turned on and decelerating at a predetermined deceleration. When switching to
It is characterized in that it is provided with deceleration adjusting means for gradually descending at a predetermined speed different from the depression amount of the brake pedal and achieving a predetermined minimum deceleration.

[0010] The inter-vehicle distance control device (4) according to the present invention includes an inter-vehicle distance measuring means, a vehicle speed detecting means,
In an inter-vehicle distance control device to which a brake switch, a control switch, a brake control means, and the like, which operate when a brake pedal is depressed , the brake switch is turned on while the control switch is turned on and the vehicle is decelerated at a predetermined deceleration. And the deceleration
Gradually increase at a predetermined speed different from the stepping amount of the
When the brake switch is switched from ON to OFF after a predetermined maximum deceleration, the maximum deceleration is gradually decreased at a predetermined speed, and deceleration adjusting means for achieving a predetermined minimum deceleration is provided. It is characterized by having.

[0011]

According to the above inter-vehicle distance control device (1), when the control switch is turned on and the vehicle is decelerating at the predetermined deceleration, when the brake switch is turned on, the deceleration is increased to the predetermined value. Then, when the brake switch is turned off, the deceleration is maintained for the predetermined time.
After that, since the increased deceleration is returned to the original deceleration, the increased deceleration does not decrease immediately after the brake switch is turned off, and the deceleration does not decrease for a predetermined time. Remains. For this reason, the driver's uncomfortable feeling of the sensational acceleration of the own vehicle, which is felt that the increased deceleration is immediately returned to the original small deceleration, is relieved.

Further, according to the inter-vehicle distance control device (2), when the control switch is turned on and the vehicle is decelerating at the predetermined deceleration, when the brake switch is turned on, the deceleration is reduced by the brake pedal. Since the deceleration is gradually increased at a predetermined speed different from the stepping amount and is moved to a predetermined maximum deceleration, the deceleration does not suddenly increase, and the operation is caused by a sudden deceleration. The discomfort of the person is relieved.

According to the inter-vehicle distance control device (3), when the control switch is turned on and the brake switch is switched from on to off during deceleration at the predetermined deceleration, the deceleration is reduced. Step on the brake pedal
Since it is gradually lowered at a predetermined speed different from the penetration amount and is moved to the predetermined minimum deceleration, even if the brake switch is turned off, the increased deceleration does not suddenly increase. It is gradually returned to the original minimum deceleration. When the vehicle is returned to the original small deceleration, the driver may easily feel that the vehicle is accelerating, but the processing is performed not suddenly but gradually, so that the driver's uncomfortable feeling is relieved.

According to the inter-vehicle distance control device (4), when the control switch is turned on and the vehicle is decelerating at the predetermined deceleration, when the brake switch is turned on, the deceleration is reduced by the brake pedal. When the brake switch is switched from ON to OFF, the maximum deceleration is gradually increased at a predetermined speed different from the depressed amount, and is followed by the predetermined maximum deceleration. Since the vehicle is gradually lowered at the predetermined speed and is moved to the predetermined minimum deceleration, the deceleration does not suddenly increase and does not cause a sudden deceleration, so that the driver's discomfort is relieved. At the same time, the raised deceleration is gradually returned to the original deceleration, not suddenly, so that the driver does not feel the physical acceleration and the distance between the vehicles is controlled without giving the driver an uncomfortable feeling. It is.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an inter-vehicle distance control device according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram schematically showing an inter-vehicle distance control device 10 according to an embodiment.
In the figure, reference numeral 1 denotes an ECU. The ECU 1 is provided with deceleration adjusting means (not shown) for adjusting deceleration, an inter-vehicle distance measuring means 2 for detecting an inter-vehicle distance to a preceding vehicle, a vehicle speed detecting means 3 for detecting a vehicle speed, and a driver. A brake switch 4 which is activated when a brake pedal is depressed, and a control switch 5 which is activated by a driver when entering control, are connected. Also, the ECU 1 includes an ECU 1
A brake control solenoid 6, a transmission gear 7, and a throttle valve 8, which are controlled by the control unit, are connected. The inter-vehicle distance control device 10 includes the ECU 1 to the throttle valve 8.

In the inter-vehicle distance control device 10, based on signals from the inter-vehicle distance measuring means 2 and the vehicle speed detecting means 3, the EC
It is determined by U1 whether or not an appropriate inter-vehicle distance is maintained. Based on the determination result of the ECU 1, brake control means such as the brake control solenoid 6, the transmission gear 7, and the throttle valve 8 are controlled to change the vehicle speed. The following distance is controlled.

FIG. 2 is a block diagram schematically showing the configuration of a brake system including the brake control solenoid 6, and 21 in the figure represents a brake pedal. The brake pedal 21 is connected to the master cylinder 22. A brake motor 24 is connected to a tip of a discharge pipe 31 extending from a master cylinder reservoir 23 installed on the master cylinder 22, and a check valve 30a is connected to the tip of the brake motor 24. The accumulator 25 is connected. The tip of the accumulator 25 is bifurcated, one is connected to a return pipe 32 via a pressure sensor 26 and a check valve 30b, and the other is connected to a three-position solenoid 28 via a solenoid 27. The master cylinder 22 is connected to a three-position solenoid 28 via a check valve 30c and a discharge pipe 33. The three-position solenoid 28 includes a wheel cylinder 29 and a check valve 30d.
Is connected to the return pipe 32 through the check valve 30d.
Is a bypass for the three-position solenoid 28.

The three-position solenoid 28 is indicated by an arrow A in the figure.
When the port 28a and the corresponding oil pipe 33a are aligned, the discharge pipe 3
3 communicates with the oil pipe 33a, and when the port 28b and the corresponding oil pipe 32a are aligned, the return pipe 32 communicates with the oil pipe 32a. Movement of the three-position solenoid 28 may close both ports 28a and 28b, but not both.
Table 1 shows combinations of the open / close states of the ports 28a and 28b.

[0019]

[Table 1]

Various patterns of the brake control in the brake system configured as described above will be described with reference to FIG. First, when the control switch 5 is turned on to perform the following distance control, the solenoid 2
7, the port 27a is opened, and at the same time, the state in which the brake motor 24 operates to apply hydraulic pressure to the wheel cylinder 29 is maintained. The pressure applied to the wheel cylinder 29 is increased or By holding or reducing the pressure, the braking force of the brake is controlled. The pressure required for the control is stored by an accumulator 25, and the pressure of the accumulator 25 is monitored by a pressure sensor 26. When the pressure drops below a specified pressure, the brake motor 24 is driven to accumulate the pressure. In addition, oil that is no longer required for pressure reduction in the brake control is returned to the master cylinder reservoir 23 via the check valve 30d.

When increasing the pressure applied to the wheel cylinder 29, the ECU 1 controls the three-position solenoid 28 to open the port 28a. Then, the operating pressure pressurized by the brake motor 24 and accumulated in the accumulator 25 passes through the port 27a of the solenoid 27 from the accumulator 25, passes through the port 28a of the 3-position solenoid 28, and pressurizes the wheel cylinder 29. As a result, the braking force of the brake is increased.

On the other hand, when the pressure applied to the wheel cylinder 29 is maintained, the three-position solenoid 28 is controlled by the ECU 1, the ports 28a and 28b are closed, and the pressure of the wheel cylinder 29 is maintained.

Further, when reducing the pressure applied to the wheel cylinder 29, the ECU 1 controls the three-position solenoid 28 to open the port 28b and open the port 28b.
8a is closed. As a result, the hydraulic pressure acting on the wheel cylinder 29 is transferred from the port 28b to the check valve 30.
d to the master cylinder reservoir 23 via
The pressure acting on the wheel cylinder 29 is reduced.

On the other hand, when the control switch 5 is turned off and inter-vehicle distance control is not performed, the port 27a is closed and the port 28a is opened, and hydraulic pressure is applied to the wheel cylinder 29 from the master cylinder 22 via the port 28a. Thus, a normal brake operation is performed.

The operation of the inter-vehicle distance control device 10 according to the first embodiment having the brake control system configured as described above will be described with reference to the flowchart shown in FIG. 3 and the timing chart shown in FIG. explain. The ECU 1 is provided with a CBR-OFF counter (not shown) as a counter that increases at regular intervals. When the brake input is turned on, the CBR-OFF counter is cleared and the brake input O
Counted up during FF. First, in step 1, it is determined whether or not the control switch 5 is operated to turn on the inter-vehicle distance control. When it is determined that the inter-vehicle distance control is not ON, the operation proceeds to another operation without performing the inter-vehicle distance control. When it is determined that the inter-vehicle distance control is ON, the process proceeds to step 2 and receives a signal from the brake switch 4 to input a brake input. Is turned on.
If it is determined that the brake input is not ON, the process proceeds to step 3 and the normal inter-vehicle distance control (hereinafter, the normal inter-vehicle distance control means that the acceleration is, for example, ± 3 m / s ² ) (FIG. 4A) Is performed and the process returns to step 1 again.
If it is determined to be ON, the process proceeds to step 4 and CB
R-OFF counter is cleared, deceleration is 4m, for example
/ S ² (FIG. 4B) (S5). Then whether the brake input proceeds to step 6 is turned off is determined, the deceleration returns to step 5 if it is not turned off is maintained at 4m / s ^2, the CBR over if it is judged to have been turned off The OFF counter is counted up (S
7). Next, in step 8, the count value is determined whether it is less than ₁ sec t, is equal to or less than t ₁ seconds (FIG. 4C) remains deceleration returns to Step 5 is 4m / s ² If it is determined that the count value has exceeded t ₁ seconds, the deceleration is set to, for example, 3 m / s ² (FIG. 4).
D) (S9). Next, proceeding to step 10, it is determined whether or not the count value is equal to or less than t ₂ seconds. If the count value is equal to or less than t ₂ seconds, the process returns to step 9 and the deceleration is maintained at 3 m / s ² , Step 3 when it is determined that t ₂ seconds has been exceeded
Then, the normal inter-vehicle distance control is performed (FIG. 4E). Note that the value of t ₂ is set to be larger about one second from t _1. As described above, the deceleration adjusting means in the present embodiment is constituted by steps 2 to 9.

In the case of the following distance control apparatus according to the first embodiment,
When control switch 5 is a brake switch 4 during following distance control is turned on is turned on, is raised from the deceleration receiving the signal, for example 3m / s ² for example up to 4m / s ^2, thereafter the brake switch 4 When the brake switch 4 is turned off, the signal is returned to the original deceleration (for example, 3 m / s ² ) after a predetermined time (t ₁ second) is received. Does not decrease, and the deceleration (4 m / s ² ) before the brake switch 4 is turned off is maintained for a predetermined time (t ₁ second). That is, after a predetermined time (t ₁ second) has elapsed, deceleration is performed for the _first time by the signal of the brake switch 4 being turned off. Therefore, it is possible to ease the driver's discomfort with the sensational acceleration of the own vehicle which is felt when the increased deceleration is immediately returned to the original small deceleration.

Next, an inter-vehicle distance control device 1 according to a second embodiment
The operation of 0 will be described based on the flowchart shown in FIG. 5 and the timing chart shown in FIG. The deceleration is α (m / s ² ), and the unit is omitted. ECU1
Is executed every second, and in step 1, it is determined whether or not the control switch 5 is operated to turn on the inter-vehicle distance control. When it is determined that the inter-vehicle distance control is not ON, the operation proceeds to another operation without performing the inter-vehicle distance control. When it is determined that the inter-vehicle distance control is ON, the process proceeds to step 2 and receives a signal from the brake switch 4 to input a brake input. Is turned on.
When it is determined that the brake input is not ON, the process proceeds to step 3 and the normal inter-vehicle distance control (α = ± 3) is performed. Then, the process returns to step 1 again. When it is determined that the brake input is ON, α = 3. A value obtained by adding 0.1 is set as a new α, and α gradually increases (S4) (FIG. 6B). Then step 5
It is determined whether or not α is greater than 5. If α is 5 or less, the process returns to step 4 and a value obtained by adding 0.1 to α is set as a new α, while α is greater than 5. In this case, the routine proceeds to step 6, where α is controlled to 5 (FIG. 6C). Next, proceeding to step 7, it is determined whether or not the brake input has been turned off. If the brake input has not been turned off, the process returns to step 6 and α is maintained at 5, and if it has been turned off, α is subtracted from 0.2 by minus 0.2. The obtained value is set to α, and α gradually decreases (S8) (FIG. 6D). Next, the process proceeds to step 9 to determine whether α is smaller than 3. If α is 3 or more, the process returns to step 8 and a value obtained by subtracting 0.2 from α is set as a new α. If it is smaller, the routine proceeds to step 10, where α is controlled to 3 (FIG. 6E). Then step 1
The count proceeds to 1 and the count value is t
₃ seconds or not is whether or less is judged (S12), the deceleration process returns to the step 10 in the case is less than t ₃ seconds 3m / s
² is maintained, and when the time exceeds t ₃ seconds, the process returns to step 3 and normal control is performed (FIG. 6F). As described above, the deceleration adjusting means in this embodiment is constituted by steps 2 to 10.

According to the inter-vehicle distance control device according to the second embodiment, the driver depresses the brake while the control switch 5 is turned on and the vehicle decelerates at a predetermined deceleration (for example, 3 m / s ² ). Is turned on, the deceleration (3 m / s ² ) is gradually increased at a predetermined speed,
When the brake switch 4 is switched from on to off after a predetermined maximum deceleration (for example, 5 m / s ² ), the maximum deceleration (5 m / s ² ) gradually decreases at a predetermined speed. And a predetermined minimum deceleration (for example, 3 m /
s ² ). Therefore, the deceleration (3 m
/ S ² ) does not suddenly increase, does not cause a sudden deceleration, and has the increased deceleration (5
m / s ² ) is gradually returned to the original deceleration, not suddenly, so that it is possible to control the inter-vehicle distance without feeling sensational acceleration and without giving the driver an uncomfortable feeling.

In this embodiment, the case where the inter-vehicle distance is controlled by controlling the brake control solenoid 6 has been described. However, the present invention is not limited to this. The control may be performed by controlling the transmission gear 7, and in another embodiment, the control may be performed by controlling the throttle valve 8.

[0030]

As can be seen from the above description, according to the following distance control apparatus (1) according to the present invention, when the control switch is turned on and the brake switch is turned on during deceleration at a predetermined deceleration. When the deceleration is increased to a predetermined value, and then the brake switch is turned off, the deceleration is maintained for a predetermined time, and then the increased deceleration is returned to the original deceleration. Immediately after being turned off, the increased deceleration does not decrease and remains for the predetermined time. For this reason, it is possible to ease the driver's discomfort with the sensational acceleration of the own vehicle, which feels that the increased deceleration is immediately returned to the original small deceleration.

According to the inter-vehicle distance control device (2) according to the present invention, when the control switch is turned on and the vehicle is decelerating at a predetermined deceleration, when the brake switch is turned on, the deceleration is depressed by the brake pedal. Since it is gradually increased at a predetermined speed different from the amount and is brought to a predetermined maximum deceleration, the deceleration does not suddenly increase, and the driver's discomfort caused by sudden deceleration is eased. be able to.

According to the inter-vehicle distance control device (3) of the present invention, when the control switch is turned on and the brake switch is switched from on to off while decelerating at a predetermined deceleration, the deceleration is shaken. -Depressing the key pedal
Since it is gradually lowered at a predetermined speed different from the control amount and is moved to a predetermined minimum deceleration, even if the brake switch is turned off, the increased deceleration is not suddenly but gradually. It is returned to the original minimum deceleration. When returning to the original small deceleration, it is easy to feel as if the own vehicle is accelerating, but since the above processing is performed gradually and not suddenly, it can ease the driver's discomfort. it can.

According to the inter-vehicle distance control device (4) of the present invention, when the control switch is turned on and the vehicle is decelerating at a predetermined deceleration, when the brake switch is turned on, the deceleration is depressed by the brake pedal. the amount and is raised gradually in a different predetermined speed is Yuka with a predetermined maximum deceleration, divided thereafter said when the brake switch is switched from oN to oFF, the maximum deceleration is the predetermined speed s At a predetermined deceleration, the deceleration does not suddenly increase, and abrupt deceleration does not occur, so that the driver's discomfort is alleviated, and the increased deceleration is reduced. Since the speed is gradually returned to the original deceleration, not suddenly, the inter-vehicle distance can be controlled without feeling uncomfortable without feeling sensational acceleration.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically illustrating an inter-vehicle distance control device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram schematically illustrating a structure of a brake system of the following distance control apparatus according to the embodiment.

FIG. 3 is a flowchart showing an operation of an ECU of the following distance control apparatus according to the embodiment.

FIG. 4 is a time chart illustrating a relationship between a brake input and a vehicle speed of the inter-vehicle distance control device according to the embodiment.

FIG. 5 is a flowchart illustrating an operation of an ECU of the following distance control apparatus according to another embodiment.

FIG. 6 is a time chart showing a relationship between a brake input and a vehicle speed of an inter-vehicle distance control device according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ECU 2 Inter-vehicle distance measuring means 3 Vehicle speed detecting means 4 Brake switch 5 Control switch 6 Brake control solenoid

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B60T ⁷ /12-8/96 B60K 31/00 B60R 21/00 G08G 1/16

Claims (4)

(57) [Claims] 1. An ECU (Electro Control Unit) includes an inter-vehicle distance measuring means, a vehicle speed detecting means, and a brake.
In an inter-vehicle distance control device to which a brake switch, a control switch, a brake control means, and the like that operate when a pedal is depressed are connected, when the control switch is turned on and the vehicle is decelerated at a predetermined deceleration, the brake switch is turned on. Increasing the deceleration to a predetermined value,
Thereafter, when the brake switch is turned off, the predetermined time is reduced.
An inter-vehicle distance control device comprising deceleration adjusting means for returning the increased deceleration to the original deceleration after maintaining the speed . 2. An inter-vehicle distance measuring means, a vehicle speed detecting means, and a brake provided in an ECU (electro control unit).
In an inter-vehicle distance control device to which a brake switch, a control switch, a brake control means, and the like that operate when a pedal is depressed are connected, when the control switch is turned on and the vehicle is decelerated at a predetermined deceleration, the brake switch is turned on. Depressing the brake pedal with the deceleration
An inter-vehicle distance control device comprising deceleration adjusting means for gradually increasing the speed at a predetermined speed different from the stuck amount and achieving a predetermined maximum deceleration. 3. An ECU (Electronic Control Unit) having an inter-vehicle distance measuring means, a vehicle speed detecting means, and a brake.
In an inter-vehicle distance control device to which a brake switch, a control switch, and a brake control means that are activated when a pedal is depressed , the brake switch is turned on from off while the control switch is turned on and decelerating at a predetermined deceleration. When switched, deceleration is braked.
An inter-vehicle distance control device comprising deceleration adjusting means for gradually descending at a predetermined speed different from the amount of depression of a pedal and moving to a predetermined minimum deceleration. 4. An ECU (Electronic Control Unit) having an inter-vehicle distance measuring means, a vehicle speed detecting means, and a brake.
In an inter-vehicle distance control device to which a brake switch, a control switch, a brake control means, and the like that operate when a pedal is depressed are connected, when the control switch is turned on and the vehicle is decelerated at a predetermined deceleration, the brake switch is turned on. Depressing the brake pedal with the deceleration
Gradually increase at a predetermined speed different from the amount of intrusion, and bring it to a predetermined maximum deceleration.After that, when the brake switch is switched from on to off, the maximum deceleration is gradually increased at a predetermined speed. An inter-vehicle distance control device, comprising: deceleration adjusting means for lowering the vehicle to a predetermined minimum deceleration.