JP7211317B2 - vehicle occupant restraint system - Google Patents

Description

The present invention relates to vehicle occupant restraint systems.

Patent Literature 1 discloses a seat belt device capable of retracting webbing by driving a motor. Here, in Patent Document 1, the motor is driven when the steering angle, the steering angular velocity, and the steering angular acceleration satisfy predetermined threshold values. On the other hand, Patent Literature 2 discloses a configuration that increases the tension of the webbing when the steering angle change rate (steering angle speed) exceeds a threshold value. Further, Patent Document 3 discloses a configuration for driving a motor of a seatbelt device when the steering angle and the steering angular velocity are equal to or greater than a predetermined threshold value while the acceleration of the vehicle is small. Further, Japanese Patent Application Laid-Open No. 2002-200001 discloses a configuration having turn control means for stabilizing the running state of the vehicle while the vehicle is turning. Webbing is wound up.

JP 2007-276540 A JP 2008-535723 A JP 2013-159191 A JP 2007-237915 A

However, there is a possibility that the webbing will be wound even when a large lateral acceleration is not acting on the vehicle, and increasing the tension of the webbing in an unnecessary situation is not preferable from the viewpoint of ensuring comfort.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an occupant restraint system for a vehicle that achieves both comfort and occupant protection performance.

A vehicle occupant restraint system according to claim 1 is capable of restraining an occupant seated on a vehicle seat by a webbing having one end wound around a winding device and the other end fixed to a vehicle seat or a vehicle body, a seat belt device capable of winding up the webbing by driving a motor provided in the winding device; a vehicle speed equal to or greater than a predetermined vehicle speed threshold; a steering angular velocity equal to or greater than a predetermined steering angular velocity threshold; a control unit that drives the motor to wind up the webbing by a predetermined amount when an estimated lateral acceleration that is estimated to act on the vehicle is greater than or equal to a predetermined acceleration threshold, and detects a steering angle. An angle sensor and a vehicle speed sensor for detecting vehicle speed are provided, wherein the steering angular speed is calculated based on the steering angle detected by the steering angle sensor, and the estimated lateral acceleration is calculated based on the vehicle speed and the vehicle speed detected by the vehicle speed sensor. When the absolute value of the steering angle is larger than the steering angle at which it is determined that the vehicle is traveling straight ahead, the vehicle speed is equal to or higher than the vehicle speed threshold and the steering angular velocity is calculated based on the steering angle. Based on the state where the angular velocity exceeds the threshold value, the motor is driven to wind the webbing by a predetermined amount when the amount of change in the steering angle becomes large.
A vehicle occupant restraint system according to claim 2 is capable of restraining an occupant seated on a vehicle seat by a webbing having one end wound around a winding device and the other end fixed to a vehicle seat or a vehicle body, a seat belt device capable of winding up the webbing by driving a motor provided in the winding device; a vehicle speed equal to or greater than a predetermined vehicle speed threshold; a steering angular velocity equal to or greater than a predetermined steering angular velocity threshold; a control unit that drives the motor to wind up the webbing by a predetermined amount when an estimated lateral acceleration that is estimated to act on the vehicle is greater than or equal to a predetermined acceleration threshold, and detects a steering angle. An angle sensor and a vehicle speed sensor for detecting vehicle speed are provided, wherein the steering angular speed is calculated based on the steering angle detected by the steering angle sensor, and the estimated lateral acceleration is calculated based on the vehicle speed and the vehicle speed detected by the vehicle speed sensor. When the absolute value of the steering angle is larger than the steering angle at which it is determined that the vehicle is traveling straight ahead, the vehicle speed is equal to or higher than the vehicle speed threshold and the steering angular velocity is calculated based on the steering angle. The motor is driven when the estimated lateral acceleration calculated based on the vehicle speed and the amount of change in the steering angle after a lapse of a predetermined time is greater than or equal to a predetermined value, with reference to a state in which the angular velocity is equal to or greater than the angular velocity threshold value. to wind up the webbing by a predetermined amount.
A vehicle occupant restraint system according to claim 3 is capable of restraining an occupant seated on a vehicle seat by a webbing having one end wound around a winding device and the other end fixed to a vehicle seat or a vehicle body, a seat belt device capable of winding up the webbing by driving a motor provided in the winding device; a vehicle speed equal to or greater than a predetermined vehicle speed threshold; a steering angular velocity equal to or greater than a predetermined steering angular velocity threshold; a control unit that drives the motor to wind up the webbing by a predetermined amount when an estimated lateral acceleration that is estimated to act on the vehicle is greater than or equal to a predetermined acceleration threshold ; When skidding is predicted or detected while the vehicle is running, the webbing is wound with a winding amount that is smaller than the winding amount of the webbing that is wound when the estimated lateral acceleration is equal to or greater than a predetermined acceleration threshold. let me take

In the vehicle occupant restraint system described in each of claims 1 to 3, one end of the webbing of the seatbelt device is wound around the winding device and the other end is fixed to the vehicle seat or the vehicle body. The webbing is configured to restrain the occupant to the vehicle seat. Further, the winding device is provided with a motor, and the webbing is wound by driving the motor. As a result, even when a large acceleration is input to the vehicle, the tension of the webbing can be increased to suppress inertial movement of the occupant.

A control unit for driving the motor is provided, and the control unit drives the motor when the vehicle speed is equal to or higher than the vehicle speed threshold, the steering angular velocity is equal to or higher than the steering angular velocity threshold, and the estimated lateral acceleration is equal to or higher than the acceleration threshold. Let In this way, by adding the estimated lateral acceleration to the conditions for driving the motor, it is possible to wind up the webbing when it is estimated that the occupant will move inertially in the vehicle width direction.

In the vehicle occupant restraint system according to claim 1 and claim 2, the steering angular velocity and the estimated lateral acceleration are calculated using the steering angle and the vehicle speed, respectively, so that the vehicle is wound before the lateral acceleration is actually input to the vehicle. A picker motor can be driven.

Further, in the vehicle occupant restraint system of claim 1 , when the absolute value of the steering angle is greater than the steering angle at which the steering angle is determined to be in a straight-ahead state, that is, when the steering is being steered to the left or right, the vehicle can be steered by a small amount of steering. Even if there is, there is a possibility that the steering angular velocity threshold and the acceleration threshold will be exceeded. In such a case, the motor is driven when the amount of change in the steering angle becomes large, with reference to the state in which the steering angular velocity is equal to or greater than the steering angular velocity threshold value. can be suppressed from being driven.

In the vehicle occupant restraint system according to claim 2 , when the vehicle is steered to the left or right, the estimated lateral acceleration, which is a condition for driving the motor, is the amount of change in the vehicle speed and steering angle based on the steering state. Calculated based on As a result, it is possible to suppress the motor from being driven even when a slight steering input is made during left and right steering.
Further, in the vehicle occupant restraint system according to claim 3, when side slip of the vehicle is predicted or detected, the webbing is wound with a smaller winding amount than when the estimated lateral acceleration is equal to or greater than the predetermined acceleration threshold. be wound up. That is, the webbing is wound up to some extent before the occupant performs a countersteering operation when the vehicle skids. Therefore, it is possible to reduce the amount of change in the tension of the webbing between before the countersteering operation and after the countersteering operation, thereby reducing discomfort felt by the passenger.

A vehicle occupant restraint system according to claim 4 is characterized in that in claim 2 , the steering angular velocity becomes equal to or greater than the steering angular velocity threshold when the steering in one direction is steered in the opposite direction. In this case, the amount of the webbing wound by the motor is reduced compared to the case where the steering angular velocity becomes equal to or greater than the steering angular velocity threshold due to the steering in the same direction from the state of being steered in one direction. Let

In the vehicular occupant restraint system according to claim 4 , when the steering is performed in the opposite direction (steering direction) during steering, the amount of webbing caused by the motor is reduced compared to when the steering is performed in the same direction (cutting direction). to reduce the amount of winding. Here, when steering in the opposite direction during steering, the amount of inertial movement of the occupant is smaller than when steering in the same direction during steering. could be higher. Therefore, by reducing the amount of webbing taken up when the vehicle is steered in the opposite direction during steering, the restraining force on the occupant can be prevented from increasing more than necessary.

A vehicle occupant restraint system according to claim 5 is the vehicle occupant restraint system according to claim 4 , wherein the control unit sets an acceleration threshold for driving the motor more when the steering is performed in the opposite direction than when the steering is performed in the same direction. Set to a large value.

In the vehicle occupant restraint system according to claim 5 , even when the same lateral acceleration is acting on the vehicle, the motor is driven when the vehicle is steered in the same direction, and the motor is driven when the vehicle is steered in the opposite direction. is not driven. That is, even if the same lateral acceleration is input when the vehicle is steered in the opposite direction and when the vehicle is steered in the same direction, the amount of inertial movement of the occupant is smaller when the vehicle is steered in the opposite direction. Therefore, by setting the acceleration threshold value in this case to a large value, it is possible to suppress an increase in the restraint force when it is estimated that the amount of inertial movement of the occupant is small.

Claim 6 is a vehicle occupant restraint system according to any one of Claims 1, 2, 4, and 5 , wherein the control unit changes from a one-way steered state to a reverse steered state. In the case where the steering angle is determined to be in a straight-ahead state, the determination element is switched from the amount of change in the steering angle to the absolute value of the steering angle within a predetermined time from the point in time when the steering angle reaches the steering angle at which the steering angle is determined to be in a straight-ahead state. When the estimated lateral acceleration calculated based on the absolute value of the steering angle is greater than or equal to a predetermined acceleration threshold, the motor is driven to wind up the webbing by a predetermined amount.

In the vehicular occupant restraint system according to claim 6 , when the steering wheel is steered in the reverse direction (steering direction) during steering, the controller controls the predetermined steering angle from the time when the steering angle reaches the steering angle at which it is determined that the vehicle is traveling straight ahead. During the time, the determination element is switched from the change amount of the steering angle to the absolute value of the steering angle. That is, if the amount of change in the rudder angle is taken as a determination factor, if the steering angle is changed during steering and the steering is further cut, the amount of change in the rudder angle at the time of steering back is also included. There is a possibility that the estimated lateral acceleration calculated based on the amount of change in will reach a predetermined acceleration threshold and the webbing will be wound up. At the early timing of cutting, that is, at the timing of transition from steering back to cutting, the occupant who is inertially moving in the width direction of the vehicle returns to the basic position in the width direction of the vehicle, so if the webbing is wound up at this timing. It is annoying for passengers. On the other hand, the absolute value of the steering angle is used as a determination factor within a predetermined time from the time when the steering angle reaches the steering angle judged to be in a straight-ahead state, and the absolute value of the steering angle is calculated based on the vehicle speed and the absolute value of the steering angle. By winding up the webbing when the estimated lateral acceleration reaches or exceeds a predetermined value, the timing of cutting is earlier, that is, the timing of transition from steering back to cutting is advanced, and the occupant is inertia in the vehicle width direction. The webbing can be wound at the timing estimated to move.

As described above, according to the vehicle occupant restraint system described in each of claims 1 to 3, it is possible to achieve both comfort and occupant protection performance.

Further, according to the vehicle occupant restraint system of claims 1 and 2, the occupant can be restrained before the occupant moves by inertia.

Furthermore, according to the vehicle occupant restraint system of claims 1 and 2 , the comfort of the occupant can be improved.

According to the vehicle occupant restraint system described in each of claims 3 to 5, it is possible to prevent the occupant from feeling uncomfortable.

According to the vehicle occupant restraint system of claim 6 , the occupant can be restrained at appropriate timing.

1 is a schematic front view of a vehicle seat to which the vehicle occupant restraint system according to the first embodiment is applied, viewed from the front side of the vehicle; FIG. 1 is a schematic side view of a vehicle interior of a vehicle to which the vehicle occupant restraint system according to the first embodiment is applied, viewed from the vehicle width direction; FIG. 1 is a block diagram showing a hardware configuration of a vehicle occupant restraint system according to a first embodiment; FIG. 2 is a block diagram showing the hardware configuration of an ECU that constitutes the vehicle occupant restraint system according to the first embodiment; FIG. 1 is a block diagram showing a functional configuration of a vehicle occupant restraint system according to a first embodiment; FIG. 6 is a flowchart showing the flow of occupant restraint processing according to the first embodiment; It is a part of the flowchart which shows the flow of a passenger|crew restraint process which concerns on 2nd Embodiment. It is a part of the flowchart which shows the flow of a passenger|crew restraint process which concerns on 2nd Embodiment. It is a part of the flowchart which shows the flow of a passenger|crew restraint process which concerns on 2nd Embodiment. It is a part of the flowchart which shows the flow of a passenger|crew restraint process which concerns on 3rd Embodiment. It is a part of the flowchart which shows the flow of a passenger|crew restraint process which concerns on 3rd Embodiment. FIG. 11 is a block diagram showing the hardware configuration of a vehicle occupant restraint system according to a fourth embodiment; FIG. 11 is a block diagram showing the functional configuration of a vehicle occupant restraint system according to a fourth embodiment; FIG. 14 is a flow chart showing the flow of occupant restraint processing according to the fourth embodiment; FIG. FIG. 11 is a graph showing the relationship between steering angle and time during occupant restraint processing according to the fourth embodiment; FIG.

<First embodiment>
A vehicle occupant restraint system 10 according to a first embodiment will be described with reference to FIGS. 1 to 6. FIG. The first embodiment is not an embodiment of the present invention but a reference example. An arrow FR, an arrow UP, and an arrow RH shown in each figure indicate the forward, upward, and rightward directions of the vehicle, respectively. In the following description, when simply using the front-rear, up-down, and left-right directions, the front-rear direction of the vehicle, the up-down direction of the vehicle, and the left-right direction when facing the front direction of the vehicle are indicated unless otherwise specified. .

As shown in FIG. 1, a vehicle seat 14 is provided in a vehicle 12 to which a vehicle occupant restraint system 10 according to this embodiment is applied. The vehicle seat 14 includes a seat cushion 16 capable of supporting the buttocks and thighs of the occupant P from the seat lower side, and a seat back 18 connected to the rear end portion of the seat cushion 16 and capable of supporting the back of the occupant P. is composed of A headrest 20 capable of supporting the head of the occupant P is provided at the upper end of the seat back 18 .

Here, the vehicle seat 14 is provided with a seatbelt device 22. The seatbelt device 22 includes a webbing 24, a tongue 26, a buckle 28, and a retractor 30 as a winding device.

The webbing 24 is formed in a long strip shape, and one end of the webbing 24 is wound around a spool 30A of a retractor 30, which will be described later. The webbing 24 is drawn upward from the retractor 30 and is hung on a belt guide 34 provided in the vehicle 12 so as to extend diagonally from the right shoulder toward the left waist of the occupant P seated on the right seat. extended.

Here, a tongue 26 is passed through the webbing 24 , and this tongue 26 is engaged with a buckle 28 provided on the vehicle seat 14 at the waist of the occupant P. The webbing 24 is folded back at a tongue 26 and extends to the right side of the seat, and the other end of the webbing 24 is fixed to an anchor 32 provided on the floor of the vehicle 12 . The webbing 24 can restrain the occupant P seated on the vehicle seat 14 . In the webbing 24, a shoulder belt portion 24A is a portion that extends obliquely in front of the upper body of the occupant P, and a lap belt portion 24B is a portion that extends left and right along the waist of the occupant P. .

The retractor 30 has a rotatable spool 30A inside, and one end of the webbing 24 is wound around the spool 30A. Further, the spool 30A is connected to a retractor motor (not shown), and by driving the retractor motor, the spool 30A is rotated in the winding direction or the pulling direction. Further, the retractor 30 is provided with a pretensioner (not shown), and when the pretensioner is activated in the event of a vehicle collision, etc., the spool 30A is forcibly rotated in the winding direction to increase the tension of the webbing 24. is configured as

As shown in FIG. 2, the vehicle seat 14 of this embodiment is a seat provided in the driver's seat of a right-hand drive vehicle, and a steering wheel 36 is provided in front of the vehicle seat 14 . Then, the passenger P grips the steering wheel 36 and steers left and right, so that the vehicle 12 turns left and right.

FIG. 3 is a block diagram showing the hardware configuration of the vehicle occupant restraint system 10. As shown in FIG. As shown in FIG. 3, the vehicle occupant restraint system 10 includes an ECU (Electrical Control Unit) 40 as a control section. The ECU 40 is also electrically connected to a steering angle sensor 42 , a vehicle speed sensor 44 , a retractor motor 46 and a pretensioner 48 .

The steering angle sensor 42 is a sensor that detects the steering angle of the steering wheel 36 , and the vehicle speed sensor 44 is a sensor that detects the speed of the vehicle 12 . The steering angle detected by the steering angle sensor 42 and the vehicle speed detected by the vehicle speed sensor 44 are input to the ECU 40 .

The retractor motor 46 is driven by a signal from the ECU 40 to rotate the spool 30A in the winding direction or the pulling direction. As a result, the webbing 24 is wound around the retractor 30 or the webbing 24 is pulled out from the retractor 30 . The pretensioner 48 is operated by a signal from the ECU 40 to forcibly rotate the spool 30A in the winding direction.

FIG. 4 is a block diagram showing the hardware configuration of the ECU 40. As shown in FIG. As shown in FIG. 4 , the ECU 40 includes a CPU (Central Processing Unit: processor) 50 , a ROM (Read Only Memory) 52 , a RAM (Random Access Memory) 54 and a storage 56 . Each component is communicatively connected to each other via a bus 58 .

The CPU 50 is a central processing unit that executes various programs and controls each section. That is, the CPU 50 reads a program from the ROM 52 or the storage 56 and executes the program using the RAM 54 as a work area. The CPU 50 performs control of the above components and various arithmetic processing according to programs recorded in the ROM 52 or the storage 56 .

The ROM 52 stores various programs and various data. RAM 54 temporarily stores programs or data as a work area. The storage 56 is configured by a HDD (Hard Disk Drive) or SSD (Solid State Drive) and stores various programs including an operating system and various data.

The vehicle occupant restraint system 10 uses the hardware resources shown in FIGS. 3 and 4 to implement various functions. A functional configuration realized by the vehicle occupant restraint system 10 will be described with reference to FIG.

As shown in FIG. 5, the vehicle occupant restraint system 10 includes a vehicle speed determination unit 60, a straight travel determination unit 62, a steering angular velocity determination unit 64, an estimated lateral acceleration determination unit 66, and a retractor motor control unit 68 as functional configurations. I have. Each functional configuration is realized by reading and executing a program stored in the ROM 52 or the storage 56 by the CPU 50 of the ECU 40 .

The vehicle speed determination unit 60 determines whether the vehicle speed of the vehicle 12 detected by the vehicle speed sensor 44 is equal to or higher than a predetermined vehicle speed threshold. The straight travel determination unit 62 determines whether the vehicle 12 is traveling straight. Specifically, it is determined whether or not the absolute value of the steering angle of the steering wheel 36 detected by the steering angle sensor 42 is smaller than a predetermined threshold (straight ahead threshold). This straight-ahead threshold is set, for example, between 30 degrees and 45 degrees.

A steering angular velocity determination unit 64 determines whether the steering angular velocity is equal to or greater than a predetermined steering angular velocity threshold. Here, in this embodiment, the steering angular velocity is calculated based on the steering angle of the steering wheel 36 detected by the steering angle sensor 42 . Specifically, the steering angular velocity is calculated by differentiating the steering angle.

The estimated lateral acceleration determination unit 66 determines whether the estimated lateral acceleration acting on the vehicle 12 is equal to or greater than a predetermined acceleration threshold. In this embodiment, the estimated lateral acceleration is calculated based on the vehicle speed detected by the vehicle speed sensor 44 and the steering angle detected by the steering angle sensor 42 . Specifically, when the vehicle speed is V and the steering angle is θ, the estimated lateral acceleration a is calculated by the following formula (1). Note that k is a coefficient determined by the shape of the vehicle 12, such as the wheelbase.

・・・・（１）

(1)

The retractor motor control unit 68 controls the direction and amount of rotation of the spool 30</b>A by the retractor motor 46 of the seat belt device 22 .

Next, the flow of occupant restraint processing by the vehicle occupant restraint system 10 will be described with reference to the flowchart of FIG. For example, the occupant restraint process is performed by the CPU 50 reading a program from the ROM 52 or the storage 56, developing it in the RAM 54, and executing it.

As shown in FIG. 6, the CPU 50 determines whether or not the vehicle speed V1 of the vehicle 12 detected by the vehicle speed sensor 44 in step S102 is greater than or equal to the vehicle speed threshold value Vt. Then, if the vehicle speed V1 is equal to or higher than the vehicle speed threshold Vt, the CPU 50 proceeds to step S104, and if the vehicle speed V1 is less than the vehicle speed threshold Vt, the processing ends.

The CPU 50 determines whether or not the steering angular velocity ω1 calculated from the steering angle θ1 of the steering wheel 36 detected by the steering angle sensor 42 in step S104 is greater than or equal to the steering angular velocity threshold ωt. If the steering angular velocity ω1 is greater than or equal to the steering angular velocity threshold ωt, the CPU 50 proceeds to step S106, and if the steering angular velocity ω1 is less than the steering angular velocity threshold ωt, the process ends.

The CPU 50 determines whether or not the estimated lateral acceleration a1 acting on the vehicle 12 in step S106 is greater than or equal to the acceleration threshold value at. Then, the CPU 50 proceeds to step S108 if the estimated lateral acceleration a1 is equal to or greater than the acceleration threshold at, and ends the process if the estimated lateral acceleration a1 is less than the acceleration threshold at. Note that in the present embodiment, the estimated lateral acceleration a1 is calculated from the above equation (1) based on the vehicle speed V1 and the steering angle θ1.

The CPU 50 operates the retractor motor 46 in step S108. Here, the CPU 50 controls the retractor motor 46 so as to rotate the spool 30A in the winding direction by a predetermined amount using the function of the retractor motor control section 68 .

As described above, in the occupant restraint process of this embodiment, when the vehicle speed V1 is equal to or greater than the vehicle speed threshold Vt, the steering angular velocity ω1 is equal to or greater than the steering angular velocity threshold ωt, and the estimated lateral acceleration a1 is equal to or greater than the acceleration threshold at, The webbing 24 is wound up by a predetermined amount. As a result, the tension of the webbing 24 is increased and inertial movement of the occupant P is suppressed.

(Action)
Next, the operation of this embodiment will be described.

In the vehicle occupant restraint system 10 of this embodiment, as shown in FIGS. 1 and 3, the retractor 30 of the seatbelt device 22 is provided with a retractor motor 46 . When the retractor motor 46 is driven, the spool 30A rotates in the winding direction and the webbing 24 is wound. As a result, when a large acceleration is input to the vehicle 12, the tension of the webbing 24 is increased to suppress inertial movement of the occupant P.

Here, the vehicle occupant restraint system 10 operates the retractor motor 46 when the vehicle speed V1 is equal to or greater than the vehicle speed threshold Vt, the steering angular velocity ω1 is equal to or greater than the steering angular velocity threshold ωt, and the estimated lateral acceleration a1 is equal to or greater than the acceleration threshold at. drive the By adding the estimated lateral acceleration a1 to the conditions for driving the retractor motor 46 in this manner, the webbing 24 can be wound up when it is estimated that the occupant P will move inertially in the vehicle width direction. As a result, it is possible to achieve both comfort and occupant protection performance.

Furthermore, in this embodiment, the steering angular velocity ω1 is calculated from the steering angle θ1, and the estimated lateral acceleration a1 is calculated from the steering angle θ1 and the vehicle speed V1. As a result, the retractor motor 46 of the retractor 30 can be driven before the lateral acceleration is actually input to the vehicle 12 . That is, the occupant P can be restrained before the occupant P moves inertially.

<Second embodiment>
Next, a vehicle occupant restraint system according to a second embodiment will be described with reference to FIGS. The second embodiment is an embodiment of the present invention. In addition, the same code|symbol is attached|subjected about the structure similar to 1st Embodiment, and description is abbreviate|omitted suitably.

A vehicle occupant restraint system 70 of this embodiment has the same configuration as that of the first embodiment except for the flow of occupant restraint processing. Therefore, in the following description, only the flow of the occupant restraint process will be described with reference to the flow charts of FIGS.

As shown in FIG. 7, the CPU 50 determines whether or not the vehicle speed V2 of the vehicle 12 detected by the vehicle speed sensor 44 in step S202 is greater than or equal to the vehicle speed threshold value Vt. Then, if the vehicle speed V2 is equal to or higher than the vehicle speed threshold Vt, the CPU 50 proceeds to step S204, and if the vehicle speed V2 is less than the vehicle speed threshold Vt, the processing ends.

The CPU 50 determines whether or not the absolute value |θ2| of the steering angle θ2 of the steering wheel 36 detected by the steering angle sensor 42 in step S204 is equal to or less than the threshold value θu. If the steering angle absolute value |θ2| is equal to or less than the threshold value θu, the CPU 50 proceeds to step S206, and if the steering angle absolute value |θ2| is greater than the threshold value θu, the CPU 50 proceeds to step S212 (see FIG. 8). ).

The CPU 50 determines in step S206 whether or not a sudden steering operation has been input. That is, when a large steering angular velocity is detected, the CPU 50 determines that a rapid steering operation has been input, and proceeds to step S208. Further, the CPU 50 terminates the processing when a large steering angular velocity is not detected.

The CPU 50 determines whether or not the estimated lateral acceleration a2 acting on the vehicle 12 in step S208 is greater than or equal to the acceleration threshold value at. The estimated lateral acceleration a2 is calculated from the vehicle speed V2 and the steering angle .theta.2 by Equation (1) described above.

If the estimated lateral acceleration a2 is equal to or greater than the acceleration threshold at in step S208, the CPU 50 proceeds to step S210, and if the estimated lateral acceleration a2 is less than the acceleration threshold at, the process ends.

The CPU 50 operates the retractor motor 46 in step S210. Here, the CPU 50 controls the retractor motor 46 so as to rotate the spool 30A in the winding direction by a predetermined amount using the function of the retractor motor control section 68 . Then the process ends.

As described above, when the steering angle absolute value |θ2| is equal to or less than the threshold value θu in step S204, that is, when the vehicle 12 is traveling straight, the same processing as in the first embodiment is performed.

On the other hand, when the steering angle absolute value |θ2| is larger than the threshold value θu as described above, the process proceeds to step S212. As shown in FIG. 8, in step S212, the CPU 50 determines whether or not the steering angle θ2 is greater than zero. Here, in the present embodiment, when the steering angle θ2 is 0 degree as a reference, when the steering angle θ2 is a positive value, the steering is to the left, and when the steering angle θ2 is a negative value, the steering is to the right. It shall be

When the steering angle θ2 is greater than 0 in step S212, the CPU 50 proceeds to step S236 (see FIG. 9). Further, when the steering angle θ2 is smaller than 0 in step S212, the CPU 50 proceeds to step S214.

(Suddenly steering in the direction of cutting while steering to the right)
The CPU 50 determines in step S214 whether or not a sudden steering operation has been input in the cutting direction. That is, in step S214, since the vehicle is being steered to the right, it is determined whether or not a sharp steering operation to the right has been input from this state.

When the sudden steering to the right is input in step S214, the CPU 50 determines that the sudden steering in the direction of additional cut is input, and proceeds to step S216. Further, if the CPU 50 does not input the sudden steering to the right in step S214, the CPU 50 proceeds to step S224.

The CPU 50 stores the current steering angle θ3 and vehicle speed V3 in step S216. That is, the CPU 50 stores the steering angle θ3 and the vehicle speed V3 in the ROM 52, the storage 56, or the RAM 54.

The CPU 50 determines whether or not a predetermined period of time has elapsed in step S218. Then, the CPU 50 shifts to the process of step S220 when a predetermined time has passed since the sudden steering in the direction of cutting was input.

The CPU 50 calculates the estimated lateral acceleration a3 that is estimated to act on the vehicle 12 in step S220. In this embodiment, the vehicle speed V3 saved in step S216 or the current vehicle speed is used as the vehicle speed. As the steering angle, the amount of change Δθ in the steering angle after a predetermined period of time has elapsed with reference to the steering angle θ3 stored in step S216 is used. After calculating the estimated lateral acceleration a3, the CPU 50 proceeds to the process of step S222.

The CPU 50 determines in step S222 whether or not the estimated lateral acceleration a3 is greater than or equal to the acceleration threshold au. Then, if the estimated lateral acceleration a3 is equal to or greater than the acceleration threshold au, the CPU 50 proceeds to step S210, and operates the retractor motor 46 . That is, the CPU 50 controls the retractor motor 46 by the function of the retractor motor control section 68 so as to rotate the spool 30A in the winding direction by a predetermined amount. If the estimated lateral acceleration a3 is less than the acceleration threshold au, the CPU 50 ends the process (see FIG. 7).

As described above, in the case where the steering is to the right, if the sharp steering is input in the additional steering direction, the webbing 24 is wound up by a predetermined amount when the amount of change in the rudder angle becomes large after the elapse of the predetermined time. to increase the restraining force of the occupant P.

(Abrupt steering in the direction of steering back while steering to the right)
If the CPU 50 determines in step S214 that no sudden steering to the right has been input, the CPU 50 proceeds to step S224 and determines whether or not a sudden steering in the direction of return has been input. That is, in step S224, it is determined whether or not a sudden leftward steering is input from the rightward steering state.

When the sudden steering to the left is input in step S224, the CPU 50 determines that the sudden steering in the direction of return is input and proceeds to step S226. Further, if the CPU 50 does not input the sudden steering to the left in step S224, the CPU 50 ends the processing (see FIG. 7).

The CPU 50 stores the current steering angle θ4 and vehicle speed V4 in step S226. That is, the CPU 50 stores the steering angle θ4 and the vehicle speed V4 in the ROM 52, the storage 56, or the RAM 54.

CPU 50 determines in step S228 whether or not a predetermined period of time has elapsed. Then, the CPU 50 proceeds to the process of step S230 when a predetermined time has elapsed since the sudden steering in the return direction was input.

The CPU 50 calculates the estimated lateral acceleration a4 that is estimated to act on the vehicle 12 in step S230. In this embodiment, the vehicle speed V4 saved in step S226 or the current vehicle speed is used as the vehicle speed. As the steering angle, the amount of change Δθ in the steering angle after a predetermined period of time has elapsed with reference to the steering angle θ4 stored in step S226 is used. After calculating the estimated lateral acceleration a4, the CPU 50 proceeds to the process of step S232.

The CPU 50 determines in step S232 whether or not the estimated lateral acceleration a4 is greater than or equal to the acceleration threshold av. Then, if the estimated lateral acceleration a4 is equal to or greater than the acceleration threshold av, the CPU 50 proceeds to step S234. If the estimated lateral acceleration a4 is less than the acceleration threshold av, the CPU 50 terminates the process (see FIG. 7). Note that in the present embodiment, the acceleration threshold av is set to a value larger than the acceleration threshold au (see step S222).

The CPU 50 operates the retractor motor 46 in step S234. That is, the CPU 50 controls the retractor motor 46 by the function of the retractor motor control section 68 so as to rotate the spool 30A in the winding direction by a predetermined amount. Here, in the present embodiment, the amount of winding of the webbing 24 in step S234 is controlled to be smaller than the amount of winding of the webbing 24 in step S210.

As described above, in the case where the steering is to the right, if a sudden steering is input in the return direction, the webbing 24 is wound up by a predetermined amount when the amount of change in the rudder angle increases after the elapse of the predetermined time. to increase the restraining force of the occupant P. In addition, the amount of winding of the webbing 24 is made smaller than that in the case where abrupt steering is input in the additional cutting direction.

(Suddenly steering in the direction of cutting while steering to the left)
Subsequently, when the steering angle θ2 is greater than 0 in step S212, the CPU 50 proceeds to step S236. As shown in FIG. 9, the CPU 50 determines in step S236 whether or not a sudden steering operation has been input in the cutting direction. That is, in step S236, since the vehicle is being steered to the left, it is determined whether or not a sharp steering operation to the left has been input from this state.

When the sudden steering to the left is input in step S236, the CPU 50 determines that the sudden steering in the direction of additional cut is input, and proceeds to step S238. Further, if the CPU 50 does not input the sudden steering to the left in step S236, the CPU 50 proceeds to step S246.

The CPU 50 stores the current steering angle θ5 and vehicle speed V5 in step S238. That is, the CPU 50 stores the steering angle θ5 and the vehicle speed V5 in the ROM 52, the storage 56, or the RAM 54.

The CPU 50 determines whether or not a predetermined period of time has elapsed in step S240. Then, the CPU 50 proceeds to the process of step S242 when a predetermined time has elapsed since the sudden steering in the direction of additional cut was input.

The CPU 50 calculates the estimated lateral acceleration a5 that is estimated to act on the vehicle 12 in step S242. In this embodiment, the vehicle speed V5 saved in step S238 or the current vehicle speed is used as the vehicle speed. Further, as the steering angle, the amount of change Δθ in the steering angle after a predetermined time has elapsed with reference to the steering angle θ5 stored in step S238 is used. After calculating the estimated lateral acceleration a5, the CPU 50 proceeds to the process of step S244.

The CPU 50 determines in step S244 whether or not the estimated lateral acceleration a5 is greater than or equal to the acceleration threshold value aw. Then, if the estimated lateral acceleration a5 is equal to or greater than the acceleration threshold value aw, the CPU 50 proceeds to step S210 and operates the retractor motor 46 . That is, the CPU 50 controls the retractor motor 46 by the function of the retractor motor control section 68 so as to rotate the spool 30A in the winding direction by a predetermined amount. If the estimated lateral acceleration a5 is less than the acceleration threshold aw, the CPU 50 ends the process (see FIG. 7).

As described above, in the case of steering to the left, if a sharp steering input is made in the direction of additional steering, the webbing 24 is wound up by a predetermined amount when the amount of change in the rudder angle increases after the elapse of a predetermined period of time. to increase the restraining force of the occupant P.

(Abrupt steering in the direction of steering back while steering to the left)
If the CPU 50 determines in step S236 that sudden steering to the left has not been input, the CPU 50 proceeds to step S246 and determines whether or not rapid steering in the reverse direction has been input. That is, in step S246, it is determined whether or not a sudden rightward steering is input from the leftward steering state.

When the sudden steering to the right is input in step S246, the CPU 50 determines that the sudden steering in the return direction is input and proceeds to step S248. Also, if the CPU 50 does not input the sudden steering to the left in step S246, the CPU 50 ends the processing (see FIG. 7).

The CPU 50 stores the current steering angle θ6 and vehicle speed V6 in step S248. That is, the CPU 50 stores the steering angle θ6 and the vehicle speed V6 in the ROM 52, the storage 56, or the RAM 54.

The CPU 50 determines whether or not a predetermined period of time has elapsed in step S250. Then, the CPU 50 proceeds to the process of step S252 when a predetermined time has elapsed since the sudden steering in the return direction was input.

The CPU 50 calculates the estimated lateral acceleration a6 that is estimated to act on the vehicle 12 in step S252. In this embodiment, the vehicle speed V6 saved in step S248 or the current vehicle speed is used as the vehicle speed. As the steering angle, the amount of change Δθ in the steering angle after a predetermined time has passed is used with reference to the steering angle θ6 stored in step S248. After calculating the estimated lateral acceleration a6, the CPU 50 proceeds to the process of step S254.

The CPU 50 determines in step S254 whether or not the estimated lateral acceleration a6 is greater than or equal to the acceleration threshold value ax. Then, if the estimated lateral acceleration a6 is equal to or greater than the acceleration threshold value ax, the CPU 50 proceeds to step S256. If the estimated lateral acceleration a6 is less than the acceleration threshold ax, the CPU 50 terminates the process (see FIG. 7). In this embodiment, the acceleration threshold ax is set to a value larger than the acceleration threshold aw (see step S244).

The CPU 50 operates the retractor motor 46 in step S256. That is, the CPU 50 controls the retractor motor 46 by the function of the retractor motor control section 68 so as to rotate the spool 30A in the winding direction by a predetermined amount. Here, in the present embodiment, the amount of winding of the webbing 24 in step S256 is controlled to be smaller than the amount of winding of the webbing 24 in step S210.

As described above, in the case where the steering is to the left, the webbing 24 is wound up by a predetermined amount when the change amount of the rudder angle becomes large after the lapse of the predetermined time when the sudden steering is input in the return direction. to increase the restraining force of the occupant P. In addition, the amount of winding of the webbing 24 is made smaller than that in the case where abrupt steering is input in the additional cutting direction.

(Action)
Next, the operation of this embodiment will be described.

In the vehicle occupant restraint system 70 of this embodiment, the conditions for winding up the webbing 24 are changed between the state in which the vehicle 12 is traveling straight and the state in which the vehicle 12 is being steered left and right. Thereby, the conditions for restraining the occupant P can be finely set. Here, when the vehicle is being steered to the left or right, there is a possibility that even a small amount of steering may exceed the steering angular velocity threshold value and the acceleration threshold value. In such a case, in the present embodiment, the retractor motor 46 is driven when the amount of change in the steering angle becomes large, with reference to a state in which the steering angle velocity is equal to or greater than the steering angular velocity threshold. Also, unnecessary driving of the retractor motor 46 can be suppressed.

Further, in the present embodiment, when the vehicle 12 is steered left and right, the estimated lateral acceleration, which is a condition for driving the retractor motor 46, is determined based on the amount of change in the vehicle speed and steering angle with reference to the steered state. calculated by As a result, it is possible to prevent the retractor motor 46 from being driven even when a slight steering input is made during left and right steering. As a result, the comfort of the passenger P can be improved.

Furthermore, in the present embodiment, when steering in the opposite direction (steering back direction), the winding amount of the webbing 24 is reduced compared to when steering in the same direction (cutting direction) during left and right steering. Decrease. Here, when the vehicle is steered in the opposite direction, the amount of inertial movement of the occupant P is smaller than when the vehicle is steered in the same direction. Therefore, by reducing the winding amount of the webbing 24 as in the present embodiment, the force restraining the occupant P does not become unnecessarily high.

Furthermore, in the present embodiment, as shown in FIG. 8, when the steering is to the right, the acceleration threshold value av (step S232) when the sudden steering is input in the direction of steering back is sharply reduced in the direction of cutting back. It is set to a value greater than the acceleration threshold au (step S222) when steering is input. Here, even when the same lateral acceleration is input when the vehicle is steered in the opposite direction and when the vehicle is steered in the same direction, the amount of inertial movement of the occupant P is smaller when the vehicle is steered in the opposite direction. Therefore, by setting different acceleration threshold values as in the present embodiment, it is possible to prevent the webbing from winding up when the amount of inertial movement of the occupant P is small. As a result, it is possible to prevent the occupant P from feeling uncomfortable.

<Third Embodiment>
Next, a vehicle occupant restraint system according to a third embodiment will be described with reference to FIGS. 10 and 11. FIG. The third embodiment is an embodiment of the present invention. In addition, the same code|symbol is attached|subjected about the structure similar to 2nd Embodiment, and description is abbreviate|omitted suitably.

The vehicle occupant restraint system 80 of this embodiment has the same configuration as that of the second embodiment except for the flow when the steering is steered in the return direction. Therefore, in the following description, only the flow of the occupant restraint process will be described with reference to the flow charts of FIGS. 10 and 11 based on the flow chart of FIG.

(Steering in the reverse direction while steering to the right)
As shown in FIG. 10, when the sudden steering to the right was not input in step S214, the CPU 50 proceeds to step S330 and determines whether or not the sudden steering in the return direction was input. That is, in step S330, it is determined whether or not leftward steering has been input from the state in which the steering is being steered to the right, and whether or not the steering angular velocity exceeds the steering angular velocity threshold ωt when the opposite leftward steering is input. to decide.

When the sudden steering to the left is input in step S330, the CPU 50 assumes that the sudden steering is input in the return direction, and proceeds to step S332. Also, if the CPU 50 does not input the sudden steering to the left in step S330, the CPU 50 ends the process (see FIG. 7).

In step S332, the CPU 50 determines whether or not the steering angle θ7 of the steering wheel 36 detected by the steering angle sensor 42 within a predetermined period of time has reached the steering angle for determining that the vehicle is traveling straight ahead, ie, 0 degrees. In other words, the CPU 50 determines whether or not the steering angle θ7 has changed between positive and negative. Then, the CPU 50 proceeds to the process of step S224 when the steering angle θ7 does not reach 0 degrees within the predetermined time.

When the steering angle θ7 reaches 0 degrees within the predetermined time in step S332, the CPU 50 proceeds to step S334 to use the absolute value of the steering angle θ7 as a determination factor, and calculates the estimated lateral acceleration a7 in step S336. Calculate. In this embodiment, the estimated lateral acceleration a7 is calculated from the above-described formula (1) based on the vehicle speed V2 and the absolute values of the steering angle θ7.

The CPU 50 determines whether or not the estimated lateral acceleration a7 acting on the vehicle 12 in step S338 is greater than or equal to the acceleration threshold as. In the present embodiment, the acceleration threshold as is set to a value larger than the acceleration threshold au (see step S222), and the occupant moves in the vehicle width direction at the estimated lateral acceleration a7 calculated from the absolute value of the steering angle θ7. It is set to a value that is estimated to move inertially.

If the estimated lateral acceleration a7 is equal to or greater than the acceleration threshold as in step S338, the CPU 50 proceeds to step S234, and if the estimated lateral acceleration a7 is less than the acceleration threshold as, the process ends (see FIG. 7).

(Steering in the direction of turning back while steering to the left)
Subsequently, as shown in FIG. 11, when the sudden steering to the left is not input in step S236, the CPU 50 proceeds to step S340 and determines whether or not the sudden steering in the return direction is input. do. That is, in step S340, it is determined whether or not steering is input to the opposite right from the state of steering to the left, and whether or not the steering angular velocity exceeds the steering angular velocity threshold ωt when the steering is input to the opposite right. to decide.

When the sudden steering to the right is input in step S340, the CPU 50 assumes that the sudden steering is input in the return direction, and proceeds to step S342. Also, if the CPU 50 does not input the sudden steering to the right in step S340, the CPU 50 ends the process (see FIG. 7).

In step S342, the CPU 50 determines whether or not the steering angle θ8 of the steering wheel 36 detected by the steering angle sensor 42 has reached 0 degrees within a predetermined period of time. In other words, the CPU 50 determines whether or not the steering angle θ8 has changed between positive and negative. Then, the CPU 50 proceeds to the process of step S246 when the steering angle θ8 does not reach 0 degrees within the predetermined time.

When the steering angle θ8 reaches 0 degrees within the predetermined time in step S342, the CPU 50 proceeds to step S344, uses the absolute value of the steering angle θ8 as a determination factor, and determines the estimated lateral acceleration a8 in step S346. Calculate. Note that in the present embodiment, the estimated lateral acceleration a8 is calculated from Equation (1) above based on the vehicle speed V2 and the absolute values of the steering angle θ8.

The CPU 50 determines whether or not the estimated lateral acceleration a8 acting on the vehicle 12 in step S348 is greater than or equal to the acceleration threshold ar. In the present embodiment, the acceleration threshold ar is set to a value larger than the acceleration threshold aw (see step S244), and the occupant moves in the vehicle width direction at the estimated lateral acceleration a8 calculated from the absolute value of the steering angle θ8. It is set to a value that is estimated to move inertially.

If the estimated lateral acceleration a8 is equal to or greater than the acceleration threshold ar in step S348, the CPU 50 proceeds to step S256, and if the estimated lateral acceleration a8 is less than the acceleration threshold ar, the process ends (see FIG. 7).

(action)
Next, the operation of this embodiment will be described.

The vehicle occupant restraint system 80 of this embodiment is similar to that of the second embodiment except that the estimated lateral accelerations a7 and a8 are calculated when the steering angles θ7 and θ8 reach 0 degrees when the vehicle is steered in the return direction. Since the configuration is similar to that of the vehicle occupant restraint system 70 of No. 2, the same effects as those of the second embodiment can be obtained. Further, when the steering is reversed (steering back direction) during steering, the CPU 50 determines the steering angle θ7 based on the amount of change in the steering angle within a predetermined time after the steering angles θ7 and θ8 reach 0 degrees. , to absolute values of θ8. That is, if the amount of change in the rudder angle is taken as a determination factor, if the steering angle is changed during steering and the steering is further cut, the amount of change in the rudder angle at the time of steering back is also included. The webbing 24 may be wound up when the estimated lateral acceleration calculated based on the amount of change in reaches a predetermined acceleration threshold. At the early timing of the cutting, that is, at the timing of transition from steering back to cutting, the occupant who is inertially moving in the vehicle width direction returns to the basic position in the vehicle width direction, so the webbing 24 is wound up at this timing. And the passenger P feels troublesome. On the other hand, within a predetermined time after the steering angles θ7 and θ8 reach 0 degrees, the absolute values of the steering angles θ7 and θ8 are used as determination factors, and based on the vehicle speed and the absolute values of the steering angles θ7 and θ8. By winding up the webbing 24 when the calculated estimated lateral accelerations a7 and a8 are equal to or greater than a predetermined value, the timing of the additional cutting is earlier, that is, the timing of the shift from the return to the additional cutting is accelerated. The webbing 24 can be wound at the timing when it is estimated that the occupant P will move inertially in the vehicle width direction. Thereby, the occupant P can be restrained at an appropriate timing.

It should be noted that in the above-described third embodiment, similarly to the second embodiment, when steering in the opposite direction (return direction) is compared with when steering in the same direction (cutting direction) during left and right steering. Although the configuration is such that the amount of winding of the webbing 24 is reduced as a result, the configuration is not limited to this and may be configured such that the amount of winding is not reduced. In addition, although the acceleration threshold is set to be different between the time of steering back and the time of cutting, the same acceleration threshold may be set. Furthermore, the conditions for winding the webbing 24 are changed between the state in which the vehicle 12 is traveling straight and the state in which the vehicle 12 is being steered left and right. The conditions for winding the webbing 24 are the same as in the steering state, and the absolute values of the steering angles θ7 and θ8 are maintained within a predetermined time after the steering angles θ7 and θ8 reach 0 degrees during the steering return. It may be configured to be a determination element.

(Fourth embodiment)
Next, a vehicle occupant restraint system according to a fourth embodiment will be described with reference to FIGS. 12 to 15. FIG. The fourth embodiment is an embodiment of the present invention. The same reference numerals are assigned to the same components as those of the first to third embodiments described above, and the description thereof will be omitted.

A vehicle occupant restraint system 90 according to the fourth embodiment has the same basic configuration as that of the first embodiment, and is characterized in that the webbing 24 is wound up when the vehicle 12 sideslip is detected or predicted. be.

12, the ECU 40 of the vehicle occupant restraint system 90 includes a steering angle sensor 42, a vehicle speed sensor 44, a retractor motor 46, a pretensioner 48, an acceleration sensor 92, a brake pressure sensor 94, and a yaw rate sensor 96. , a road surface condition detection sensor 98, a traction control system (hereinafter simply referred to as "TRC") 100, an antilock braking system (hereinafter simply referred to as "ABS") 102 and a vehicle stability control system (hereinafter simply referred to as " VSC”) 104 is electrically connected.

The acceleration sensor 92 is a sensor that detects longitudinal and lateral accelerations of the vehicle 12, and the brake pressure sensor 94 is a sensor that detects brake hydraulic pressure caused by a driver's braking operation. The yaw rate sensor 96 is a sensor that detects the rotational angular velocity of the vehicle 12 about the vertical axis, and the road surface condition detection sensor 98 is a sensor that detects the wet condition, compacted snow condition, frozen condition, etc. of the road surface.

The TRC 100 is a system that detects slipping of the wheels and controls the rotational force, and the ABS 102 controls the braking force of the wheels in order to avoid locking the wheels during braking. The VSC 104 controls the rotational force of the wheels according to the yaw rate and the steering angle in order to prevent the vehicle 12 from skidding or the like on a low μ road.

The vehicle occupant restraint system 90 implements various functions using the hardware resources shown in FIG. A functional configuration realized by the vehicle occupant restraint system 90 will be described with reference to FIG. 13 .

As shown in FIG. 13, the vehicular occupant restraint system 90 includes a vehicle speed determination unit 60, a straight travel determination unit 62, a steering angular velocity determination unit 64, an estimated lateral acceleration determination unit 66, a sideslip determination unit 106, and a retractor A motor control unit 68 is provided. Each functional configuration is realized by the CPU 50 of the ECU 40 reading out and executing a side-slip program stored in the ROM 52 or the storage 56 .

The skid determination unit 106 predicts or early skids of the vehicle 12 based on information obtained from the acceleration sensor 92, the brake pressure sensor 94, the yaw rate sensor 96, and the road surface condition detection sensor 98, and the operation signals of the TRC 100, the ABS 102, and the VSC 104. to detect.

Next, the flow of occupant restraint processing by the vehicle occupant restraint system 90 will be described with reference to the flowchart of FIG. For example, the occupant restraint process is performed by having the CPU 50 read out a skidding program from the ROM 52 or the storage 56, develop it in the RAM 54, and execute it.

As shown in FIG. 14, CPU 50 determines whether vehicle speed V3 of vehicle 12 detected by vehicle speed sensor 44 in step S400 is equal to or greater than vehicle speed threshold Vt. Then, if the vehicle speed V3 is equal to or higher than the vehicle speed threshold Vt, the CPU 50 proceeds to step S402, and if the vehicle speed V3 is less than the vehicle speed threshold Vt, the processing ends.

The CPU 50 determines in step S402 whether or not skidding of the vehicle 12 has been predicted in advance or detected in an early stage. If the side slip of the vehicle 12 is predicted or detected early, the CPU 50 proceeds to step S404, and if the side slip of the vehicle 12 is not predicted or detected early, the process ends.

The CPU 50 operates the retractor motor 46 in step S404. Here, the CPU 50 controls the retractor motor 46 so as to rotate the spool 30A in the winding direction by a predetermined amount using the function of the retractor motor control section 68 . In this embodiment, the winding amount of the spool 30A in step S404 is less than the winding amount when the estimated lateral acceleration a1 in the first embodiment is equal to or greater than the acceleration threshold value at (see step S108 in FIG. 6). It is

(Action and effect of the fourth embodiment)
Next, the operation and effects of the fourth embodiment will be described.

Even with the above configuration, the configuration is the same as that of the vehicle occupant restraint system 10 of the first embodiment, except that the webbing 24 is wound up when the side slip of the vehicle 12 is detected or predicted. A similar effect can be obtained. Further, the webbing 24 is wound with a smaller winding amount than when the estimated lateral acceleration a1 becomes equal to or greater than the acceleration threshold at when the side slip of the vehicle 12 is predicted or detected. That is, the webbing 24 is wound up to some extent before the occupant P performs the countersteering operation when the vehicle 12 skids. That is, as shown in FIG. 15, when skidding of the vehicle 12 is predicted or early detected in a state where there is no change in the steering angle (state A in the drawing), the webbing 24 is wound up to some extent and the occupant In the state (state B in the drawing) in which a sudden steering is input by P performing a countersteering operation, the webbing 24 is further wound up. Therefore, the amount of change in the tension of the webbing 24 before the countersteering operation (state A in the drawing) and during the countersteering operation (state B in the drawing) can be reduced, so that the occupant P can feel a sense of discomfort. As a result, it is possible to prevent the occupant P from feeling uncomfortable.

Although the first to fourth embodiments have been described above, it is needless to say that various modifications can be made without departing from the gist of the present invention. For example, in the above embodiment, as shown in FIG. 1, the retractor 30, which is a winding device, is provided on the vehicle body side, but the present invention is not limited to this. That is, a so-called seat-equipped seat belt device in which the retractor 30 and the belt guide are provided on the vehicle seat 14 may be employed. In this case, the other end of the webbing 24 is fixed to the vehicle seat 14 .

Further, in the second embodiment, the amount of winding of the webbing 24 in step S234 is controlled to be smaller than the amount of winding of the webbing 24 in step S210, but the present invention is not limited to this. For example, the amount of winding of the webbing 24 may be the same amount.

Furthermore, in the second embodiment, the acceleration threshold value av (step S232) when abrupt steering is input in the steering back direction is greater than the acceleration threshold au (step S222) when abrupt steering is input in the cutting direction. value, but is not limited to this. For example, the acceleration threshold av and the acceleration threshold au may be set to approximately the same value.

Further, the processing executed by the CPU 50 by reading the software (program) in the above embodiment may be executed by various processors other than the CPU. The processor in this case is a PLD (Programmable Logic Device) whose circuit configuration can be changed after manufacturing such as an FPGA (Field-Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit) for executing specific processing. A dedicated electric circuit, which is a processor having a specially designed circuit configuration, is exemplified. Further, the above processing may be executed by one of these various processors, or a combination of two or more processors of the same or different type (for example, a plurality of FPGAs, a combination of a CPU and an FPGA, etc.). ) can be run. Further, the hardware structure of these various processors is, more specifically, an electric circuit in which circuit elements such as semiconductor elements are combined.

Furthermore, in the above embodiment, the storage 56 is used as a recording unit, but the present invention is not limited to this. For example, a recording medium such as a CD (Compact Disk), a DVD (Digital Versatile Disk), and a USB (Universal Serial Bus) memory may be used as the recording unit.

10 vehicle occupant restraint system 12 vehicle 14 vehicle seat 22 seat belt device 24 webbing 30 retractor (winding device)
40 ECU (control unit)
42 steering angle sensor 44 vehicle speed sensor 46 retractor motor (motor)
70 vehicle occupant restraint system 80 vehicle occupant restraint system 90 vehicle occupant restraint system P occupant

Claims (6)

A webbing having one end wound around a winding device and the other end fixed to a vehicle seat or a vehicle body can restrain an occupant seated on the vehicle seat, and drive a motor provided in the winding device. a seat belt device capable of winding up the webbing with
The motor is driven when the vehicle speed is equal to or greater than a predetermined vehicle speed threshold, the steering angular velocity is equal to or greater than a predetermined steering angular velocity threshold, and the estimated lateral acceleration acting on the vehicle is equal to or greater than a predetermined acceleration threshold. a control unit that winds up the webbing by a predetermined amount;
has
Equipped with a steering angle sensor for detecting a steering angle and a vehicle speed sensor for detecting a vehicle speed,
The steering angular velocity is calculated based on the steering angle detected by the steering angle sensor,
The estimated lateral acceleration is calculated based on the vehicle speed detected by the vehicle speed sensor and the steering angle,
When the absolute value of the steering angle is greater than the steering angle determined to be in a straight-ahead state, the control unit determines a state in which the vehicle speed is equal to or higher than the vehicle speed threshold and the steering angular velocity is equal to or higher than the steering angular velocity threshold. an occupant restraint system for a vehicle, which drives the motor to wind up the webbing by a predetermined amount when the amount of change in the steering angle increases . A webbing having one end wound around a winding device and the other end fixed to a vehicle seat or a vehicle body can restrain an occupant seated on the vehicle seat, and drive a motor provided in the winding device. a seat belt device capable of winding up the webbing with
The motor is driven when the vehicle speed is equal to or greater than a predetermined vehicle speed threshold, the steering angular velocity is equal to or greater than a predetermined steering angular velocity threshold, and the estimated lateral acceleration acting on the vehicle is equal to or greater than a predetermined acceleration threshold. a control unit that winds up the webbing by a predetermined amount;
has
Equipped with a steering angle sensor for detecting a steering angle and a vehicle speed sensor for detecting a vehicle speed,
The steering angular velocity is calculated based on the steering angle detected by the steering angle sensor,
The estimated lateral acceleration is calculated based on the vehicle speed detected by the vehicle speed sensor and the steering angle,
When the absolute value of the steering angle is greater than the steering angle determined to be in a straight-ahead state, the control unit determines a state in which the vehicle speed is equal to or higher than the vehicle speed threshold and the steering angular velocity is equal to or higher than the steering angular velocity threshold. Then, when the estimated lateral acceleration calculated based on the vehicle speed and the amount of change in the steering angle after a lapse of a predetermined time reaches or exceeds a predetermined value, the motor is driven to wind the webbing by a predetermined amount. vehicle occupant restraint system . A webbing having one end wound around a winding device and the other end fixed to a vehicle seat or a vehicle body can restrain an occupant seated on the vehicle seat, and drive a motor provided in the winding device. a seat belt device capable of winding up the webbing with
The motor is driven when the vehicle speed is equal to or greater than a predetermined vehicle speed threshold, the steering angular velocity is equal to or greater than a predetermined steering angular velocity threshold, and the estimated lateral acceleration acting on the vehicle is equal to or greater than a predetermined acceleration threshold. a control unit that winds up the webbing by a predetermined amount;
has
When side slipping during running of the vehicle is predicted or detected, the control unit controls the amount of winding of the webbing that is less than the amount of winding of the webbing to be wound when the estimated lateral acceleration is equal to or greater than a predetermined acceleration threshold. an occupant restraint system for a vehicle, wherein the webbing is wound at a . When the steering angular velocity becomes greater than or equal to the steering angular velocity threshold as a result of steering in the opposite direction from the state of steering in one direction, the control unit steers in the same direction from the state of steering in one direction. 3. The vehicle occupant restraint system according to claim 2 , wherein the amount of winding of the webbing by the motor is reduced compared to when the steering angular velocity becomes equal to or greater than the steering angular velocity threshold. 5. The vehicle occupant restraint system according to claim 4 , wherein when the vehicle is steered in the opposite direction, the controller sets the acceleration threshold for driving the motor to a larger value than when the vehicle is steered in the same direction. When the steering in one direction is steered in the opposite direction, the control unit sets the determination element to the steering angle for a predetermined time after the steering angle reaches the steering angle at which the steering is determined to be in a straight-ahead state. When the change amount is switched to the absolute value of the steering angle and the estimated lateral acceleration calculated based on the vehicle speed and the absolute value of the steering angle is greater than or equal to a predetermined acceleration threshold, the motor is driven to control the webbing. is wound up by a predetermined amount,
A vehicle occupant restraint system according to any one of claims 1, 2, 4 and 5 .

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