JP3506122B2 - Vehicle occupant protection system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle occupant protection system.

[0002]

2. Description of the Related Art To protect passengers in the event of a vehicle collision,
Each passenger seat is equipped with a seat belt device that restrains the passenger to the seat. The collision of the vehicle includes a front collision in which the own vehicle collides (follows a collision) with a front obstacle such as a front vehicle, and a rear collision in which the rear vehicle collides with the own vehicle.

A rear-end collision, which is a rear-end collision from a rear vehicle, is difficult for an occupant of the subject vehicle, which is a front vehicle that often faces the front, to assume in advance. For this reason, a radar or the like detects the inter-vehicle distance (relative distance) and the relative speed between the own vehicle and the rear vehicle, and when a rear-end collision is predicted based on these information, the seat belt of the own vehicle is strengthened. By pulling, the restraint of the occupant of the vehicle with respect to the seat is performed.

In Japanese Unexamined Patent Publication No. 9-175327, a distance sensor detects a relative distance to a rear vehicle, while t1,
When two types of judgment reference values t2 (t1> t2) are set and the time t to the rear collision obtained from the distance sensor is between t1 and t2, there is a possibility of a rear collision. In order to alert the occupant of this, the tension of the seat belt is increased / decreased, and if the time t becomes less than t2, it is time to predict a rear collision, and the tension of the seat belt is increased to make the occupant strong on the seat. Those that are restrained are disclosed.

[0005]

When the above-mentioned control for preventing a rear-end collision is performed, it is mistaken that a rear-side vehicle approaches and a warning is erroneously generated or a rear-end collision occurs erroneously even though there is no rear-side vehicle. It was found that there is a possibility that the seat belt will be pulled strongly. After pursuing such a cause, it was found that the sensor that detects the rear object recognizes the wall surface of the guardrail or the like on the outside of the turn as a rear vehicle.

Explaining this point in detail, for the above-mentioned rear-collision response control and alarm control when there is a possibility of a rear-collision, the detection wave is transmitted backward and the reflected wave is received. A sensor such as a distance sensor that detects the distance to the rear vehicle is used, but when traveling on a sharp curve or turning right or left at an intersection, the attitude change with respect to the wall surface of the vehicle is This is because it is often the case that the distance between the vehicle and the wall surface gradually decreases, and as a result, it is determined that the wall surface as the rear object is gradually approaching the vehicle. did.

In order to prevent a fixed object such as a guardrail from being erroneously recognized as a rear vehicle, it is conceivable to perform a process of distinguishing the solid object from the rear vehicle, but the fixed object and the rear vehicle are clearly distinguished. It is quite difficult to do. Further, in order to perform the identification, it is necessary to perform image processing on the rear video image captured by the camera, which results in a large cost increase.

The present invention has been made in view of the above circumstances, and an object thereof is to erroneously remove a rear object due to a fixed object without performing special processing for distinguishing the fixed object from a vehicle behind. It is an object of the present invention to provide a vehicle occupant protection device capable of preventing a collision response control or a warning of a rear collision possibility from being issued.

[0009]

In order to achieve the above object, the present invention has the following means for solving the problem. That is, as described in claim 1 in the scope of claims, a rear-collision predicting means for predicting a rear-end collision and restraint of an occupant by a seat belt when a rear-end collision is predicted by the rear-end collision predicting means. A rear collision response increasing means, a vehicle speed detecting means for detecting a vehicle speed, a steering angle detecting means for detecting a steering angle of the steering wheel, a vehicle speed detected by the vehicle speed detecting means is a predetermined vehicle speed or more, and the steering angle detecting means When the detected steering angle is equal to or greater than a predetermined steering angle, a prohibition means for prohibiting the operation of the rear-collision response means and an occupant by the rear-collision response means according to the vehicle speed detected by the vehicle speed detection means. And a restraint time changing means for changing the time for which restraint time is increased.

A preferred mode on the premise of the above solution method is as described in claims 2 and 3 in the claims.

[0011]

According to the invention described in claim 1, it is determined whether or not the fixed object behind is misidentified as if it approaches the host vehicle and the vehicle speed and the steering wheel. It is possible to prevent a situation in which the corresponding control at the time of predicting a rear collision is erroneously performed due to the presence of a fixed object in the rear by performing the determination by a simple method of using the angle and the identification. In addition, one of the conditions for prohibiting response control at the time of predicting a rear impact
For example, since the vehicle speed is equal to or higher than a predetermined value, for example, when waiting at a state where the steering angle of the steering wheel is greatly turned to the right or left at the intersection (the vehicle speed is 0 when stopped),
When a rear vehicle approaches and collides later, it is possible to properly perform the corresponding control at the time of predicting a rear collision. In addition to the above, by changing the time during which the occupant is restrained according to the vehicle speed, both occupant protection at the time of a rear-end collision and ensuring the vehicle operability required for handling after a rear-end collision are satisfied at a high level. Can be made.

According to the second aspect of the present invention, it is possible to prevent a situation in which a rear collision possibility is erroneously issued due to a fixed object at the rear. According to the third aspect of the present invention, when the vehicle speed at which the vehicle operation for handling after a rear collision becomes unnecessary is 0 or almost 0, it is extremely preferable from the viewpoint of restraining the occupant for a long time and protecting the occupant. Also, when the vehicle speed is high, the time for restraining the occupant can be shortened, and the state can be quickly shifted to a state in which the vehicle operation for handling after a rear collision can be performed easily.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 is a host vehicle, 2 is a rear vehicle, and an occupant seated on a seat 3 of the host vehicle 1 is designated by a symbol J. As is known, the seat 3 has a seat cushion 3a, a seat back 3b, and a headrest 3c.

A seat belt device for restraining the occupant J with respect to the seat 3 is designated by reference numeral 10. Seat belt device 1
0 is a three-point type that is generally used for general vehicles. That is, the belt 11 of the seat belt device 10
Is pulled out from the pretensioner device 12 fixed to the bottom of the vehicle body, once extends upward, and then passes through an anchor 13 located at a high place of the vehicle body, and its tip is fixed to the vehicle bottom. On the other hand, a buckle 14 is fixed to the bottom of the vehicle body on the left and right sides of the fixing portions of the belt 11 to the vehicle body, and is slidably attached to the portion of the belt 11 after passing through the anchor 13. The tongue 15 is detachably connected to the buckle 14. Since such a seat belt device 10 is well known, detailed description thereof will be omitted.

The pretensioner device 12 includes a belt 1
For example, a motor 16 is provided as a driving unit that pulls 0. By driving this motor 16, the belt 11
1 is strongly pulled toward the pretensioner device 12 side as indicated by the arrow in FIG. 1, and the restraint of the occupant J on the seat 3 is enhanced.

A distance sensor 21 as a distance detecting means is mounted on the rear portion of the vehicle 1. This distance sensor 2
1 is a detection wave (light, radio wave or ultrasonic wave) directed backward
Is emitted and the reflected wave from the rear vehicle 2 is received to detect the relative distance to the rear vehicle 2. Further, the own vehicle 1 is equipped with a warning device 22 such as a buzzer and a lamp for warning of the possibility of a rear collision, and a controller U constituted by using a microcomputer.

The control system associated with the controller U is shown in block diagram form in FIG. In FIG. 2, reference numeral 23 is a vehicle speed sensor (vehicle speed detecting means) that detects the vehicle speed of the host vehicle 1, and 24 is a steering angle sensor that detects the steering angle of the steering wheel of the host vehicle 1 (23 and 24 in FIG. (Not shown). Note that FIG.
Although not shown in FIG. 2, the sensor 31 shown by the alternate long and short dash line in FIG.
Is used in another embodiment described later, and is, for example, a headrest 3c (see FIG. 1) and is a distance sensor 31 that detects a distance between the head of the occupant J and the headrest 3c. ing.

Next, the outline of the control by the controller U will be described with reference to FIG. 3. First, the points of the rear collision response control and the rear collision possibility warning control executed before that will be described. Then, the control for prohibiting each control will be described.

Basically, the rear-end collision response control is performed by the motor 1.
The operation start time of 6 is set to a fixed time such as a predetermined time (for example, 0.5 seconds) before the time when a rear collision is predicted. Further, the time at which the warning is started when there is a possibility of a rear collision is set as the time at which the inter-vehicle distance between the rear vehicle 2 and the host vehicle 1 reaches a predetermined distance, and the predetermined distance is as follows. Is set. That is, a characteristic line is set with the relative speed and the distance as parameters, and the characteristic line indicates a direction in which the vehicle 2 approaches the host vehicle 1 at the time when the rear vehicle 2 decelerates at a predetermined deceleration and a rear collision is predicted. The relative speed is set to just zero. Then, the above-mentioned predetermined distance at which the alarm is started is set as the distance when the current relative speed is obtained by matching this characteristic line.

In FIG. 3, the relative speed of the rear vehicle 2 in the approaching direction to the host vehicle 1 (hereinafter referred to as the relative speed means the approaching direction) and the distance are set as parameters. In the figure, α1 is the distance to the host vehicle 1 when the relative speed with the rear vehicle at that time is maintained until the collision, which corresponds to the time 0.5 seconds before the time when the vehicle 1 collides with the host vehicle 1 again. Show. The numerical value of "0.5 seconds" is, for example, "0.4 seconds" as the operating time of the motor 16 required before the collision.
Second ”and the control cycle of the controller U described later is“ 0.1
In consideration of "seconds", the minimum time is set so that the state in which the belt 11 is strongly pulled by the motor 16 is surely secured even at the time of a rear collision.

The characteristic line α1 indicates that, when the relative speed is 80 km / h, the time when the rear vehicle 2 approaches the own vehicle 1 to approximately 10 m is 0.5 seconds before the rear collision time. Similarly, when the relative speed is 40 km / h, it means that the time when the rear vehicle 2 approaches the own vehicle 1 to approximately 5 m is 0.5 seconds before the rear collision time. In other words, the time when the inter-vehicle distance between the host vehicle 1 and the rear vehicle 2 becomes the distance obtained from the characteristic line of α1 according to the relative speed is the operation start time of the motor 16. The characteristic line of α2 is α
1 is shown for comparison with No. 1, and when the rear vehicle 2 maintains the relative speed at that time until the collision, it is 1.0 second before the time when the rear-end collision is predicted. It shows the inter-vehicle distance between the vehicle 1 and the rear vehicle 2.

On the other hand, the characteristic lines β1 to β3 show (the change in) the limit inter-vehicle distance between the host vehicle 1 and the rear vehicle 2 when the rear vehicle 2 is decelerated at a constant deceleration. That is, β1 indicates the change in the inter-vehicle distance at the limit of no collision between the rear vehicle 2 and the host vehicle 1, assuming that the rear vehicle 2 is decelerated from each speed by a constant deceleration of 0.8 G. Yes, similarly, β2 indicates a change in the inter-vehicle distance at the limit of no collision between the rear vehicle 2 and the host vehicle 1 when the rear vehicle 2 is decelerated at a constant deceleration of 0.6 G. Yes, β3 indicates a change in the inter-vehicle distance at the limit of no collision between the rear vehicle 2 and the host vehicle 1 when it is assumed that the rear vehicle 2 has decelerated at a constant deceleration of 0.4G.

According to the current relative speed, one of the characteristic lines β1 to β3 is selected as will be described later, and the current relative speed is collated with the selected characteristic line β1, β2 or β3. The determined distance is set as a determination reference value D (distance threshold). That is, when the actual inter-vehicle distance between the host vehicle 1 and the rear vehicle 2 becomes equal to or less than the determination reference value D, there is a possibility of a rear collision, and the alarm means 21 is activated.

As is clear by comparing β1 to β3 and α1 in FIG. 3, when the relative speed is large, α1
Between .beta.1 and .beta.3 becomes larger (distance deviation). This means that the larger the relative speed (the higher the risk of rear impact), the more the vehicle 1 and the rear of the vehicle when the warning means 21 is activated. The larger the inter-vehicle distance to the vehicle 2 and the larger the relative speed, the earlier the alarm will be started (alarm with a margin).

On the other hand, when the relative velocity becomes small, for example, α
When 1 and β1 are compared, the relative velocity is approximately 28k
At m / h or less, the inter-vehicle distance obtained by β1 becomes smaller than the inter-vehicle distance obtained by α1. This means that when the relative speed is 28 km / h or less, β1 is used to determine the inter-vehicle distance that determines the alarm start time.
There is no time to warn that there is a possibility of a rear-end collision. Therefore, when the relative speed is small, β2 is used instead of β1. Similarly, even if β2 is used, when the relative speed is 22 km / h or less, the inter-vehicle distance obtained from β2 becomes less than the inter-vehicle distance obtained from α1, and there is no time to warn the possibility of a rear-end collision. Therefore, the relative speed is 22 km.
Below / h, β3 is used instead of β2.

The relative speed is extremely small, for example, 15
When the speed is less than km / h, the impact of the rear-end collision is small, and therefore the rear-end collision possibility is not warned. Summarizing the above comprehensively, the timing at which the operation of the motor 16 as the rear-end collision prediction control is started is a fixed time (0.5 seconds before) at which the rear-end collision is predicted (own vehicle). 1
And a distance between the vehicle 2 and the rear vehicle 2 becomes a distance obtained by comparing the current relative speed with the characteristic line α1). Further, the inter-vehicle distance between the host vehicle 1 and the rear vehicle 2 when starting the operation of the alarm means 21 (a reference value for the possibility of a rear collision)
Is based on β1 when the relative speed is greater than 28 km / h, based on β2 when the relative speed is between 22 km / h and 28 km / h, and between 15 km / h and 22 km / h. In this case, the relative speed is determined as a parameter based on β3.

A concrete example of the above-mentioned control contents by the controller U is shown in the flowchart of FIG. 4 (various characteristic lines shown in FIG. 3 are stored in the memory of the controller U). Hereinafter, FIG. 4 will be described. In the following description, Q represents a step. First, in Q1, the sensor 2
After the inter-vehicle distance d between the host vehicle 1 and the rear vehicle 2 detected in 1 is read, the change amount of the inter-vehicle distance d in Q2 (deviation between the inter-vehicle distance obtained last time and the inter-vehicle distance obtained this time) Based on, the relative speed V in the direction in which the rear vehicle 2 approaches the host vehicle 1 is calculated.

In Q3, the characteristic line β to be used is selected based on the relative velocity V obtained in Q2. That is, as described above, when the relative speed is greater than 28 km / h, β1 is selected and the relative speed is 22 km / h.
To 28 km / h, β2 is selected, and when the relative speed is between 15 km / h and 22 km / h, β3 is selected. Thereafter, in Q4, the predetermined distance D (determination reference value) corresponding to the relative speed V is determined using the characteristic line selected in Q3 among the characteristic lines β1 to β3.

At Q5, it is judged if the inter-vehicle distance d between the host vehicle 1 and the rear vehicle 2 is less than or equal to the judgment reference value D. If YES in the determination in Q5, in Q6,
The alarm means 21 is activated. After this Q6 or Q5
If the determination is NO, the process proceeds to Q7. Q7
Then, whether the value obtained by dividing the inter-vehicle distance d by the relative speed V (corresponding to the time until the rear collision) is a predetermined time (0.5 seconds as described above in the embodiment) or not. To be determined.
When the determination in Q7 is NO, the process returns to Q1, and when the determination in Q7 is YES, the motor 16 is operated and the seat belt 11 is strongly pulled in Q8.

FIG. 5 shows another embodiment of the present invention and corresponds to FIG. In the present embodiment, the determination reference value D is changed according to the distance between the head of the occupant J and the headrest 3c. That is, when the distance L between the head of the occupant J and the headrest 3c detected by the sensor 31 is greater than a predetermined value (for example, 100 mm), it is determined that the degree of danger is high, and the characteristic line β3 is set to advance the alarm time. Is selected and the characteristic line β1 is selected when the distance L is less than or equal to a predetermined value, which means that the degree of danger is small.

Based on the above, in Q11 of FIG. 5, the own vehicle 1 and the rear vehicle 2 detected by the sensor 21 are detected.
And the distance L between the head of the occupant J and the headrest 43c detected by the sensor 31 are read. In Q12, the relative speed V is calculated based on the inter-vehicle distance d (same as Q2 in FIG. 4).

After that, in Q13, it is judged whether or not the distance L is less than or equal to a predetermined value. Y is determined by this Q13
In the case of ES, the characteristic line β1 is selected in Q14. When the determination in Q13 is NO, the characteristic line β3 in Q15 is selected. After Q14 or Q15, respectively, in Q16, the selected characteristic line β1
Alternatively, the judgment reference value D corresponding to the relative speed V is determined based on β3. After that, the processing after Q17 is performed, but since these processing is exactly the same as the processing after Q5 in FIG. 4, the duplicated description will be omitted.

Next, the prohibition of the rear-collision response control and the rear-collision possibility response control described above will be described with reference to FIG. 6 and subsequent figures. First, regarding a situation where a fixed object is mistakenly recognized as a rear vehicle. This will be described with reference to FIGS. 6 and 7. Figure 6
Shows the time when the host vehicle 1 is traveling on a sharp curve, and shows the case where the host vehicle 1 is traveling from the broken line state to the solid line state (there is no rear vehicle). In FIG. 6, when a wall surface 41 such as a guardrail exists on the side of the traveling road on the outside of the turning of the vehicle 1, the distance sensor 21 detects that the wall surface 41
Will be detected. The detection distance to the wall surface 41 at the center position in the directivity direction of the distance sensor 21 is the distance (large distance) to point X1 when the host vehicle 1 is in the broken line state, and the host vehicle 1 has traveled to the solid line state. In this case, the distance is a distance (small distance) to the point X2, and the detected distance changes in the direction of decreasing, and it is erroneously recognized as if the vehicle behind exists and is approaching the host vehicle 1 rapidly.

FIG. 7 shows a situation where a vehicle turns right at an intersection, and shows a case where the host vehicle 1 is traveling from a broken line state to a solid line state (no rear vehicle). In FIG. 7, the own vehicle 1
A wall 42 such as a guardrail is provided on the side of the road on the outside of the turning
Is present, the distance sensor 21 will detect the wall surface 42. The detection distance to the wall surface 42 at the center position of the directional direction of the distance sensor 21 is the distance (large distance) to the point Y1 when the host vehicle 1 is in the broken line state, and
Is the distance (small distance) to the point Y2 when the vehicle has traveled to the solid line state, the detection distance changes in the direction of decreasing, and it is as if the rear vehicle is present and the vehicle 1 is rapidly approaching. It will be misunderstood.

In both cases of FIG. 6 and FIG. 7, the steering wheel is large and the steering angle turned to the right or left is large. In addition, the wall 41 or 42 is mistaken for a vehicle behind,
This is the case where the detection point of the distance sensor 21 changes from the X1 point to the X2 point (in the case of FIG. 6) or the Y1 point or the Y2 point (in the case of FIG. 7). It is caused by the existence. From this, in the present invention, when the vehicle speed is equal to or higher than the predetermined vehicle speed and the steering wheel steering angle is equal to or higher than the predetermined steering angle, the above-described FIG.
Alternatively, the control of FIG. 5 is prohibited.

FIG. 8 shows the control contents for determining whether to prohibit the control of FIG. 4 or the control of FIG. 5 based on the vehicle speed and the steering angle as described above. In the following description, S indicates a step. First, in S1 of FIG. 8, the vehicle speed sensor 2
The vehicle speed v of the host vehicle 1 detected in 3 and the steering angle h detected by the steering angle sensor 24 are read.

At S2, it is judged if the vehicle speed v is equal to or higher than a predetermined vehicle speed VB (for example, 5 km / h). This S2
When the determination is YES, it is determined in S3 whether the steering angle h is equal to or greater than a predetermined steering angle HB (for example, 90 degrees). If YES in the determination in S3, the control in FIG. 4 or 5 described above in S4 is prohibited, and the process directly returns.

If NO in the determination of S2 or NO in the determination of S3, the process proceeds to S5, and the control of FIG. 4 or the control of FIG. 5 described above is executed. In the embodiment, the description has been made on the premise that the control content of S5 is the control of FIG. 4 or FIG. 5, but as a modified example, FIG.
In the step before Q5 or in the step before Q13 in FIG. 5, the processes of S1 to S3 of FIG. 8 are performed, and if the determination in S3 is YES, the process is returned as it is and the process of Q5 or less or Q13 or less is not performed. While doing
When the determination in S2 is NO or the determination in S3 is NO, the process may proceed to Q3 or Q13. Further, the control of FIG. 8 is interrupted with respect to the control of FIG. 4 or 5, and the control prohibition flag is set in S4, while the control permission flag is set in S5, and the control prohibition flag is set in S5. It is also possible to switch between the prohibition and the allowance of the alarm and the control for dealing with the rear collision according to the state of this flag.

FIG. 9 shows an example in which the time during which the rear-collision response control is executed is variably controlled. That is, the motor 1
When the occupant J is restrained by energizing 6 to operate the restraint time, which is the time from cutting off the power to the motor 16 to releasing the restraint of the occupant J, depending on the vehicle speed, Here is an example: In addition, the flowchart of FIG.
4 shows the details in Q8 of FIG. 4 or Q20 of FIG. 5 (control starts when power supply to the motor 16 starts).

Based on the above, the vehicle speed v of the vehicle 1 detected by the vehicle speed sensor 23 in S11 of FIG.
Is read, it is determined in S12 whether the vehicle speed v is 0 or almost 0 (for example, 5 km / h or less). If the determination in S12 is YES, the restraint time T is set to a long time T1 (for example, 3 seconds). When the determination in S12 is NO, the restraint time T is set to a short time T2 (for example, 1 second) in S14.

After S13 or S14, S
15, the restraint time T from the start of energization of the motor 16
After waiting for the passage of time, the energization of the motor 16 is cut off in S16. By cutting off the energization of the motor 16, the occupant J leans forward to operate the steering wheel, or positively and lightly pulls the seat belt 11 to pull out the seat belt in the same manner as a normal seat belt. Therefore, the restraint of the occupant J is weakened. (While the motor 16 is energized, the seat belt 11 is still strongly pulled by the torque of the motor 16, and the occupant J pulls the seat belt 11 strongly. Seat belt 1
1 is not withdrawn).

The fact that the vehicle speed is almost 0 (particularly 0) means that there is no need to operate the host vehicle 1 after a rear-end collision, and at this time the restraining time of the occupant J is lengthened. The viewpoint of protecting the occupant J becomes strong. On the other hand, the vehicle speed (especially high vehicle speed) of the host vehicle 1 at the time of a rear impact
The existence of the vehicle is a situation in which there is a high possibility that it is necessary to actively perform the driving operation of the host vehicle 1 from the viewpoint of avoiding a secondary collision after a rear collision. Then, the restraint of the occupant J by the seat belt 11 is quickly released, which is preferable for appropriately operating the vehicle such as the steering wheel and the brake.

In the example of FIG. 9, the case where the restraint time of the occupant J is changed in two steps is shown, but the restraint time can be set as shown in FIG. 10, for example. In the example of FIG. 10, the restraint time when the vehicle speed is 0 or almost 0 is set to the upper limit value (for example, 3 seconds), and the restraint time when the vehicle speed is equal to or higher than the predetermined vehicle speed (for example, 40 km / h) is set to the lower limit value ( For example, 1 second) is set, and in the vehicle speed range during this period, the restraint time is set to be continuously variable as the vehicle speed increases. Note that the change of the restraint time according to the vehicle speed can be appropriately set, for example, by setting it in three or more stages.

Although the embodiment has been described above, the present invention is not limited to this, and includes the following cases, for example. Using both the relative velocity V and the distance L as parameters,
The characteristic lines β1 to β3 may be selected. The characteristic lines (β1 to β3) can be set to only two types or four or more types. The determination reference value D may be changed in a continuously variable manner based on the relative speed V and the distance L (for example, three characteristic lines β1, β2, β3 are set, and the characteristic lines between them are interpolated). Etc.).

As the seat belt device 10, an appropriate type such as a four-point type can be adopted. The time to start the alarm is set with a time setting such as a predetermined time before the time when the collision is predicted as described in the above-mentioned publication, and the time before this predetermined time is, for example, the relative speed V or the distance L.
It can be changed according to The alarm means 21 may be set to increase or decrease the tensile force of the seat belt 11, but the response delay is small and the occupant J does not.
It is preferable to adopt a buzzer (sound warning) that can be surely notified. The road surface μ (friction coefficient) may be estimated, and the selectable characteristic line may be limited in accordance with the estimated road surface μ (from the limited characteristic line, the relative speed V or the distance L may be set). Selected accordingly). For example, three characteristic lines β1 to β
In addition to 3, if a characteristic line β4 equivalent to 0.2 G for low friction is set and the estimated road surface μ is large, β1 is set.
When the estimated road surface μ is small, it is possible to select from β2 to β4 so as to select only from β3 to β3.

The present invention can be similarly applied to an occupant protection system that executes only one of rear collision response control (restraint by seat belt) and warning when there is a possibility of a rear collision. Further, among the controls of the present invention, the control related to the seat belt can be performed only for the driver's seat (the occupant in the driver's seat) (prohibition control and restraint time for the passenger seat and the rear seat). No change control). Each step (group of steps) shown in the flowchart or various members such as a sensor can be expressed by adding the name of the means to the higher level expression of its function. Further, the function of each step (step group) shown in the flow chart can be expressed as the function of the functional unit set in the control unit (controller U) (the existence of the functional unit). Of course, the object of the present invention is not limited to what is specified, and also implicitly includes providing what is expressed as substantially preferable or advantageous. Furthermore, the present invention can be expressed as a control method.

[Brief description of drawings]

FIG. 1 is a simplified side view showing a host vehicle and a rear vehicle.

FIG. 2 is a block diagram showing a control system equipped in the host vehicle.

FIG. 3 is a diagram showing various characteristic lines used in a control example of the present invention.

FIG. 4 is a flowchart showing an example of rear-end collision response control and alarm control when there is a possibility of rear-end collision.

FIG. 5 is a flowchart showing another example of the rear-collision response control and the alarm control when there is a possibility of a rear-collision.

FIG. 6 is a simplified plan view illustrating a situation in which a fixed object is mistakenly recognized as a rear vehicle.

FIG. 7 is a simplified plan view illustrating another situation in which a fixed object is mistakenly recognized as a rear vehicle.

FIG. 8 is a flowchart showing a control example for preventing a situation in which a rear-end collision response control or the like is performed based on a fixed object.

FIG. 9 is a flowchart showing an example of control for changing an occupant restraint time by a seat belt.

FIG. 10 is a diagram showing another example of setting an occupant restraint time by a seat belt.

[Explanation of symbols]

1: Own vehicle 2: Rear vehicle 3: Sheet 3c: seat back 10: Seat belt device 11: Belt 12: Pretensioner device 16: Motor (for belt tension) 21: Distance sensor (for rear vehicle detection) 22: Alarm means 23: Vehicle speed sensor 24: Rudder angle sensor 31: Distance sensor (for headrest) J: Crew U: Controller

Continuation of front page (51) Int.Cl. ⁷ Identification code FI B60R 21/00 626 B60R 21/00 626A

Claims (3)

(57) [Claims] 1. A rear-collision predicting means for predicting a rear-end collision, a rear-collision response means for enhancing restraint of an occupant by a seat belt when a rear-end collision is predicted by the rear-collision predicting means, and a vehicle speed. Vehicle speed detecting means, steering angle detecting means for detecting the steering angle of the steering wheel, vehicle speed detected by the vehicle speed detecting means is a predetermined vehicle speed or more, and steering angle detected by the steering angle detecting means is a predetermined steering angle or more. In this case, depending on the vehicle speed detected by the vehicle speed detection means and the prohibition means for prohibiting the operation of the rear collision response means , the rear collision
Change the time to keep the restraint of the occupant high by means of time response.
An occupant protection device for a vehicle , further comprising restraint time changing means . 2. The rear-collision possibility detecting means for detecting a possibility of a rear-collision, even if the rear-collision prediction is not performed, and the rear-collision possibility detecting means according to claim 1. When we detect the possibility,
An occupant protection device for a vehicle, further comprising: an alarm unit for issuing an alarm, wherein the prohibition unit is set so as to prohibit the operation of the alarm unit. 3. The restraint time of the occupant by the restraint time changing means as set forth in claim 1 , when the vehicle speed is 0 or almost 0, as compared with when the vehicle speed is 0 or greater than 0. An occupant protection device for a vehicle.