JP2001039269A - Vehicular passive safety device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent unnecessary external force application to occupants by pretensioners and ensure appreciable maneuverability of accelerator pedals and brake pedals by the occupants, by setting more appropriate conditions to trigger the pretensioners in case of a rear-end collision or a prediction thereof. SOLUTION: Upon a rear-end collision or a prediction thereof, a pretensioner motor basically pulls a seat belt 11 tight to elevate the restraint on an occupant J against a seat 1. If the interval between the upper body of the occupant J and a seat back 3 is larger than a first predetermined value to indicate an excessive interval or is smaller than a second predetermined value to indicate an upper body of the occupant J well leaned back against the seat back 3, the pretensioner is disabled or the working torque of the motor is reduced.

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 using a seat belt.

[0002]

2. Description of the Related Art In a vehicle, particularly an automobile, an occupant is restrained to a seat by a seat belt for protecting the occupant. In general, a three-point seat belt is often used. The three-point seat belt is basically
A front end portion of the seat belt pulled out from a retractor connected to the vehicle body is connected to the vehicle body on one of the left and right sides of the seat, and a first engagement portion (tongue) attached to an intermediate portion of the seat belt is the other of the left and right sides of the seat. The side is detachably engaged with a second engaging portion (buckle) connected to the vehicle body. In such a three-point seat belt, the seat belt pulled out from the retractor is:
The shoulder portion that mainly restrains the occupant's shoulder and the wrap portion that mainly restrains the failed portion of the occupant can be distinguished from the first engagement portion that engages with the second engagement portion.

In order to effectively protect the occupant in connection with a collision, it has been proposed to forcibly pull the seat belt by means of a pretensioner. JP-A-9-17532
No. 7 proposes to increase the restraint of an occupant on a seat by pulling a seat belt by a pretensioner at the time of a rear collision or a rear collision prediction. In this publication, whiplash, which tends to occur due to a rear collision, is particularly prevented or suppressed.

[0004]

It is preferable to uniformly pull the seat belt by the pretensioner at the time of rear collision or at the time of rear collision prediction, particularly at the time of rear collision prediction. There is still room for improvement. That is, the fact that the pretensioner is activated and the occupant is restrained by the seat belt to the seat back means that an unexpected external force is applied to the occupant, and there is room for improvement in this respect. Operating the pretensioner while the occupant is quite far away from the seat back means that at least the occupant's upper body is displaced considerably toward the seat back, which means that the steering wheel or accelerator pedal However, the relative positional relationship with the brake pedal changes considerably, and there is room for improvement from the viewpoint of ensuring sufficient operability for handling a collision.

The present invention has been made in view of the above circumstances, and an object of the present invention is to optimize the operation control of a pretensioner at the time of a rear collision or a rear collision prediction so that an occupant can use the seat belt. Provided is a vehicle occupant protection device that prevents unnecessary external force that is likely to be unexpectedly directed toward the vehicle from being applied and that ensures sufficient operability of a steering wheel, an accelerator pedal, and a brake pedal. It is in.

[0006]

In order to achieve the above object, the present invention has a first solution as follows. That is, in a vehicle occupant protection device including a control means for operating a pretensioner that pulls a seat belt at the time of a rear collision prediction or a rear collision, as described in claim 1 of the claims, Distance detecting means for detecting a separation distance between the body and the seat back; and restriction for restricting operation of the pretensioner by the control means when a distance detected by the distance detecting means is larger than a first predetermined value. Means. Preferred embodiments based on the above solution are as described in Claims 3 and the following claims.

In order to achieve the above object, the present invention is as follows as a second solution. That is, in the vehicle occupant protection device provided with control means for operating the pretensioner for pulling the seat belt at the time of rear collision prediction or rear collision as described in claim 2 of the claims, A distance detecting means for detecting a separation distance between the body and the seat back; and a restriction for restricting an operation of the pretensioner by the control means when a distance detected by the distance detecting means is smaller than a second predetermined value. Means. A preferred embodiment based on the above solution is described in claim 3 of the appended claims.
It is as described below.

[0008]

According to the first aspect, when the upper body of the occupant is far away from the seat back, the operation of the pretensioner is restricted, so that the upper body of the occupant sharply and largely turns toward the seat back. This prevents or suppresses displacement of the steering wheel, and prevents or suppresses deterioration of operation of the handle or the like. Of course, unexpectedly large external force acting on the occupant's upper body is also prevented or suppressed, and a situation in which the occupant is surprised is also prevented. When the pretensioner is operated as usual when the occupant's upper body is largely separated from the seat back, whiplash may be promoted, but such a situation is also preferable in preventing or suppressing such a situation. It will be.
According to the second aspect, when the upper body of the occupant is close to the seat back, the operation of the pretensioner is restricted, thereby preventing or suppressing unexpectedly large external force from acting on the upper body of the occupant. Therefore, a situation in which the occupant is surprised is prevented. Further, since the upper body of the occupant is close to the seat back, there is no particular problem in preventing whiplash even if the operation of the pretensioner is restricted. Of course, it is preferable to prevent or suppress a sudden pressing of the occupant's upper body toward the seat back, and to prevent or suppress deterioration of the operation of the steering wheel and the like.

According to the third aspect, the operation of the pretensioner is restricted by prohibiting the operation of the pretensioner.
The effect corresponding to claim 1 or claim 2 can be sufficiently exhibited. According to the fourth aspect, the distance between the occupant's upper body and the seat back can be easily and accurately detected by the distance sensor. According to claim 5,
The distance between the upper body of the occupant and the seat back can be detected by effectively using the distance sensor provided in the front of the passenger compartment. In particular, when a distance sensor is provided on the front of the passenger compartment for controlling the operation of the front airbag, the distance sensor for the front airbag can be used as it is.

According to the present invention, when the distance sensor provided on the front of the vehicle compartment is used, the distance between the occupant's upper body and the seat back can be determined with high accuracy. Claim 7
According to this configuration, it is possible to obtain a configuration that is more simple than that of the sixth embodiment, while obtaining substantially the same effect as the effect corresponding to the sixth embodiment. According to the eighth aspect, even when the occupant is sitting on a seat while holding the luggage or the like, the distance to the occupant can be accurately detected without making the luggage or the like noise. According to the ninth aspect, a specific configuration is provided in a general three-point seat belt as a seat belt.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 1 and 2, reference numeral 1 denotes a driver's seat, the seat cushion of which is denoted by reference numeral 2, the seat back denoted by reference numeral 3, and the headrest denoted by reference numeral 4. A steering handle operated by an occupant J seated on the seat 1 is indicated by reference numeral 5, and the handle 5
Is equipped with an airbag device 6.

Three-point seat belt device 10 for seat 1
Is a retractor 12 for winding up the seat belt 11.
The retractor 12 is fixed to the vehicle body (B pillar in the embodiment) at a lower right rear position of the seat cushion 2. The front end portion of the seat belt 11 pulled out from the retractor 12 is fixed to the vehicle body (in the embodiment, a floor panel) using the fixing device 13 at a low position immediately to the right of the seat cushion 2. A buckle 15 is fixed to a vehicle body (a floor panel in the embodiment) via a fixing member 14 at a low position immediately to the left of the seat cushion 2.

The guide member 16 is fixed to the vehicle body (B pillar in the embodiment) at a position slightly higher than the seat back 4 in the normal use state (standing state) of the right high position of the seat 1. . The seat belt 11 pulled out from the retractor 12 once extends upward, is slidably inserted through the guide member 16, and then has its tip fixed to the vehicle body via the fixing member 13 as described above. I have. A tongue 17 is slidably held at an intermediate portion of the seat belt 11, more specifically, at a portion between the guide member 16 and the fixture 13. The tongue 17 is detachably engaged with the buckle 15 described above. The tongue 17 constitutes a first engaging portion, and the buckle 15 constitutes a second engaging portion. The tongue 17 is provided on the vehicle body side, and the buckle 15 is provided on the seat belt 11 side. Can also.

With the seat belt 11 positioned in front of the occupant J seated on the seat 1, the tongue 17 is engaged with the buckle 15 so that the occupant J can seat as shown in FIGS. I am bound by 1. That is, the occupant J is restrained by the seat 1, that is, the vehicle body by the retractor 12, the fixing device 13, and the buckle 15 (the fixing device 14) via the seat belt 11. Thus, the retractor 12 serves as a first connection to the vehicle body, the fixing device 13 serves as a second connection to the vehicle body, and the buckle 15
Is a third connecting portion to the vehicle body. When the occupant J is restrained by the seat belt 11, the tongue 17 (buckle 15) of the seat belt 11
Is a shoulder portion 11a that mainly restrains the occupant J from the shoulder to the chest, and a portion that extends from the tongue 17 to the fixture 13 is a wrap portion 1 that mainly restrains the lumbar portion of the occupant J.
1b.

The retractor 12 is provided with a pretensioner (pretensioner device) and a lock means. The details of the retainer 12 will be described below with reference to FIGS. First, the case of the retainer 12 which is a fixed portion to the vehicle body is indicated by reference numeral 21, and the axis of the winding shaft for the seat belt 11 rotatably held by the case 21 is indicated by reference numeral 22. One side of the case 21 is provided with a spring mechanism 23 using a mainspring, and the spring mechanism 23 applies a biasing force for winding the seat belt 11 to the winding axis 22 (winding axis). Has been granted.

The back of the case 21, that is, the seat belt 1
On the side opposite to the pull-out position of No. 1, an electric motor 24
Has been fixed. The motor 24 is used for a pretensioner, and is connected to the winding axis 22 via an electromagnetic clutch 25 and a speed reducer 26. Case 11
Of these, a lock means 27 is attached on the side opposite to the spring mechanism 23. As is known, when the seat belt 11 is pulled at a speed higher than a predetermined speed, that is, when the winding axis 22 is rotated in the seat belt pull-out direction at a speed higher than the predetermined rotation speed, Lock the rotation of the winding axis 22,
An operation of locking the drawer of the seat belt 11 is performed.

FIG. 5 shows a control system. In the figure, U is a control unit constituted by using a microcomputer. The control unit U receives signals from various sensors, switches, and the like from S1 to S7. The switch S1 is a switch for detecting whether or not the occupant J is properly equipped with the seat belt 11. For example, the switch S1 is provided on the buckle 15 and is turned ON when the tongue 17 is properly engaged with the buckle 15. . Sensor S2
Is an angle sensor for detecting the reclining angle of the seat back 3. The sensor S3 detects the sliding position of the seat 1, that is, the seat cushion 2, in the front-rear direction. The sensor S4 is provided on the instrument panel 31, and the occupant J is provided from the rear end of the instrument panel 31.
Is a distance sensor that detects the distance to the face of the user (or the chest can be directed to the vicinity of the upper end of the seat back 3). The sensor S5 is provided on the seat cushion 2 and detects the weight (and the presence) of the occupant J seated on the seat 1.

The sensor S6 is provided at (near the upper end of) the seat back 3 and detects a pressing force (a degree applied by the seat back 3) from the occupant J seated on the seat 1. The sensor S7 is a rear collision prediction sensor, and performs rear collision prediction. This rear collision prediction sensor S7
For example, the control unit U is configured using a radar that detects an obstacle behind the vehicle, and from the distance to the obstacle and the relative speed detected by the radar, for example, determines whether the possibility of collision is high or not. Is determined. Sensor S8
Is a G sensor (acceleration sensor), which is turned on when the acceleration generated in the vehicle body when a rear collision is equal to or more than a predetermined value,
This is to detect a rear collision. Devices controlled by the control unit U include a pretensioner (motor 2).
4) In addition to the airbag 6, an alarm 41 including a lamp, a buzzer, or the like (preferably an alarm by sound) is included.

Next, an example of the operation control of the pretensioner will be described with reference to the flowchart of FIG. The flowchart in FIG. 6 is started when rear-end collision prediction is detected (determined), and Q indicates a step in the following description. First, in Q1, it is determined whether or not the seat belt switch S1 is ON, that is, whether or not the seat belt 11 is being worn. If the determination in Q1 is YES, in Q2, the seat slide position SS based on the output from the sensor S3 and the reclining angle θ based on the output from the sensor S2.
And the distance D2 from the rear end of the instrument panel 31 to the face of the occupant J based on the output of the distance sensor S4.

In Q3, the distance DX from the rear end of the instrument panel 31 to the upper end of the seat back 3, ie, the headrest 4, is determined from the seat slide position SS and the reclining angle θ. In Q4, an appropriate distance range L1 to L2 (L1 <L2) from the rear end of the instrument panel 31 to the face position of the occupant J is determined in consideration of the distance DX. The appropriate distance range L1 to L2 is a range in which the separation distance of the occupant J from the seat back 3 is neither too small nor too large. In determining the appropriate distances L1 and L2, it is assumed that the head width (length in the front-rear direction) of the occupant J is a standard size.

In Q5, based on the output of the sensor S5,
It is determined whether or not the load applied to the seat cushion 2 from the occupant J is equal to or greater than a predetermined value P1. When the determination of Q5 is NO, the determination of Q5 is repeated, but the process may return to Q1. If the determination in Q5 is YES, Q
In 6, it is determined whether or not the load applied to the seat back 3 from the occupant J is equal to or greater than a predetermined value P2 based on the output from the sensor S2. If the determination in Q6 is YES, in Q7 the distance D detected by the distance sensor S4
It is determined whether or not 2 is within the appropriate distance range L1 to L2.

If the determination in Q7 is YES, the separation distance of the occupant J from the seat back 3 is within an appropriate range (the occupant J
Is sitting in an almost standard posture), in which case Q8
In, the motor 24 is operated with the medium torque serving as the reference torque (the pretensioner is operated). Of course, the magnitude of the operating torque of the motor 24 indicates the magnitude of the pulling force of the seat belt 11. If NO in Q7, it is determined in Q9 whether the distance D2 is smaller than L1. If the determination in Q9 is YES, Q
At 10, the motor 24 is operated with a high torque (the pretensioner is activated). When the process of Q10 is performed, it is possible that the occupant J has a large physique or holds luggage. If the determination in Q9 is NO, in Q11, the motor 24 is operated with a low torque (the pretensioner is activated). The process of Q11 is performed when the occupant J is sufficiently in contact with the seat back 3.

If the determination in Q6 is NO, the process shifts to Q12, where it is determined whether or not the distance D2 is between the distance ranges L3 and K4, which is slightly larger than the distance ranges L1 and L2. It is determined (L3 <L1 <L2 <L4). If the determination in Q12 is YES, in Q13, the motor 24 is operated with a high torque (the pretensioner is activated). The process of Q13 is performed when the occupant J is slightly too far from the seat back 3. Q1
If the determination in step 2 is NO, in Q14 the motor 24
Operation is prohibited (no pretensioner operation). The process of Q14 may be performed when the occupant J is far too far from the seat back 3 or when the occupant J is bending his / her body forward or sideways.

As is clear from the above description, in the control example of FIG. 6, the operation of the pretensioner is prohibited when the occupant J is far too far from the seat back 3. It should be noted that instead of the determination of Q6, it is also possible to determine whether or not the separation distance of the occupant J from the seat back 3 is equal to or less than a predetermined value, and to proceed to Q7 when the determination is YES. .

FIG. 7 is a flowchart showing another control example of the present invention. First, in Q21, when it is confirmed that the occupant J is seated on the seat 1 based on the output of the sensor S5 and that the seat belt 11 is fastened based on the output of the switch S1, in Q23, It is determined whether the possibility of a rear collision is large (determined based on the output of the rear collision prediction sensor S7).

If the determination in Q23 is YES, the operation gain A of the pretensioner is changed in Q24 based on the detection distance between the upper body of the occupant J and the headrest 4 in FIG.
(0 ≦ A ≦ 1). The operation gain A is for determining the magnitude of the operation torque of the motor 24. When the operation gain A is 1, the reference torque is used. The smaller the operation gain A, the smaller the operation torque. The operating gain A is set to 1 when the detection distance is between the appropriate distance ranges β3 and β4, is gradually decreased as the detection distance becomes smaller than the predetermined value β3, and is decreased rapidly when it is larger than β4. Is finally set to 0. After Q24, in Q25, the final torque G1 is calculated by multiplying the reference torque by the operation gain A. Thereafter, in Q26, the alarm 4
1 is operated, and in Q27, the motor 24 is operated with the final torque G1 (the pretensioner is operated).

NO after Q27 or in Q23
In the case of, in Q28, it is determined whether or not a rear collision has been detected based on the output of the G sensor S8.
If the determination in Q28 is YES, in Q29,
The operation gain B of the motor 24 is determined as shown by a broken line in FIG. The operation gain B is set to 1 when the detection distance between the upper body of the occupant J and the headrest 4 is equal to or less than β1 which is sufficiently small, and is rapidly decreased as the detection distance becomes larger than β1 to finally become 0. Is set to Thereafter, in Q30, the final torque G2 is calculated by multiplying the reference torque by the operation gain B. Thereafter, in Q31, the motor 24 is operated with the final torque G2 (the pretensioner is operated). When the occupant J does not exist (NO in the determination of Q21), when the seat belt 11 is not fastened (NO in the determination of Q22), and when NO in the determination of Q28,
Returned respectively.

As a modification of FIG. 7, the following is also possible. First, when the rear collision is predicted, as shown in FIG. 9, the motor 24 is turned off only when the detection distance between the upper body of the occupant J and the headrest 4 is between the predetermined range β3 and β4. The motor 24 can be operated at the reference torque, and at other times, the operation of the motor 24 can be prohibited. Further, at the time of rear collision detection, as shown in FIG. 9, the motor 24 can be operated with the reference torque only when the detected distance is equal to or shorter than the predetermined distance β1, and the operation of the motor 24 can be prohibited at other times. .

FIG. 10 shows an example in which the distance X between the upper body of the occupant J and the upper end of the seat back, that is, the headrest 4, can be accurately detected by using the distance sensor S4 provided on the instrument panel 31. It is shown. First, as shown in FIG. 11, the distance Dh between the headrest 4 and the rear end of the instrument panel 31 is accurately known from the seat slide position (detected by the sensor S3) and the seat back reclining angle (detected by the sensor S2). Can be. Also, the face of the occupant J and the instrument panel 31
The distance Li to the rear end can be accurately known by the distance sensor S4. The head width (length in the front-rear direction) Fp of the occupant J
Can be accurately determined from the map shown in FIG. 12 based on the weight indicating the physical size of the occupant J (detected by the sensor S5) (the larger the weight, the larger the head width Fp). Then, the finally obtained distance X between the occupant J and the headrest 4 is obtained by a calculation formula of X = Dh-Li-Fp. In the above formula, only the head width Fp causes a slight error, and the distance X finally obtained is considerably high in accuracy. Note that the value of Fp may be set to a constant as a predicted value, and the distance X may be determined without calculating Fp separately.

FIG. 13 shows an example in which a sensor S10 for directly detecting the distance between the head of the occupant J and the headrest 4 is provided in the headrest 4. That is, of the headrest 4, a cushion body is indicated by reference numeral 51, and a frame is indicated by reference numeral 52. The frame 52 has a pair of left and right attachment legs 52 a serving as attachment portions to the seat back 3, and the attachment legs 5 in the cushion body 51.
It has a pair of upper and lower connecting portions 52b and 52c for connecting the 2a to each other. The cushion body 51 has an opening 51a at a substantially central portion thereof, and the lower connecting portion 52c is located near the lower end edge of the opening 51a. And
The distance sensor S10 is fixed to the connecting portion 52c in a state where the distance sensor S10 is disposed in the opening 51a.

FIGS. 14 and 15 show another example in which a sensor S10 for directly detecting the distance between the head of the occupant J and the headrest 4 is provided on the headrest 4, and FIG.
The same components as those in 3 are denoted by the same reference numerals, and the description thereof will not be repeated. In the present embodiment, the mounting recess 51 is provided on the front surface of the cushion body 51 so as to face the lower connecting portion 52c.
b is formed. The distance sensor S10 is disposed in the mounting recess 51b and fixed to the connecting portion 52c.

FIGS. 16 to 21 show an example in which an inexpensive pressure-sensitive switch (pressure sensor) can be used to detect the state of the occupant J sitting on the seat 1 without using a distance sensor. . In the present embodiment, as shown in FIG. 16, the rear upper surface of the seat cushion 2 and the seat back 3
, And a pair of left and right pressure-sensitive switches 61, 62, 63 are provided on the front surface of the upper end and the front surface of the lower end of the seat back 3. The pressure-sensitive switches 61 to 63 are turned on when a load equal to or more than a predetermined value is received. The combination of the ON and the OFF changes the seating posture state of the occupant J as shown in FIGS. Are detected (classified) as posture 1 to posture 4. Then, according to the detected posture state, the operation of the pretensioner is controlled as shown in FIG.

The posture 1 shown in FIG. 18 is a standard sitting posture, and the pretensioner is operated as usual (with normal torque). In posture 2 shown in FIG. 19, although the upper body of the occupant J is slightly separated from the upper end of the seat back 3 as compared with posture 1, the posture is close to the standard posture which is almost the same as posture 1. In this case, The pretensioner is operated as usual, or the pretensioner is operated with a higher torque than usual. The posture 3 shown in FIG. 20 is when the upper body of the occupant J is completely separated from the seat back 3. In this case, the pretensioner is operated with low torque, or the operation of the pretensioner is prohibited. You. The posture 4 shown in FIG. 21 is an upper body in which the occupant J is largely separated from the seat back 3, and in this case, the operation of the pretensioner is prohibited.

FIG. 22 shows the upper body of the occupant J and the headrest 4.
FIG. 9 shows another example of detecting a distance between. In the present embodiment, for example, FIGS.
While a distance sensor S10 is provided as shown in FIG. 15, a pressure switch 64 which is turned on when a load equal to or more than a predetermined value is received is provided on the front surface of the upper end of the seat back 3. When the pressure switch 64 is ON, the occupant J
It is determined that the upper body is sufficiently close to the seat back 3, and this determination result is used for the operation control of the pretensioner. When the pressure switch 64 is OFF,
The detection distance detected by the distance sensor S10 is used for controlling the operation of the pretensioner.

Although the embodiment has been described above, the present invention is not limited to this and includes, for example, the following case. The same applies to seats other than the driver's seat. As a drive source of the pretensioner, a fluid cylinder may be used instead of the motor 24, for example. The pretensioner can also be configured to pull the buckle 15, in which case it is desirable to provide an electromagnetic locking means to prevent the seat belt 11 from being pulled out of the retractor 12 when the pretensioner is activated. .

The buckle 15 may be provided on the seat belt 11 side, while the tongue 17 may be provided on the vehicle body side. Of course, if detachable engagement is possible, an engaging member other than the buckle and the tongue can be used. The seat belt device is not limited to the three-point type and may be of an appropriate type such as a two-point type or a four-point type. By restricting the operation of the pretensioner only at the time of rear collision prediction,
In the event of a rear collision, the operation of the pretensioner may not be restricted. Conversely, the operation of the pretensioner may be restricted only at the time of a rear collision, and the operation of the pretensioner may not be restricted at the time of a rear collision prediction. Instead of the distance sensor S4 provided on the instrument panel 31, as shown in FIG.
A distance sensor S4 for detecting the distance to the occupant J
A can also be provided, in this case, the occupant J
Even if the user is carrying luggage or the like, it is possible to prevent the luggage or the like from becoming noise for distance detection. When the seat belt device is for a rear occupant, a sensor S4 (S4A) may be provided in the vehicle compartment in front of the rear occupant (for example, the sensor S4A is installed on a roof above the driver's seat. Provided).

The operation gain of the pretensioner (corresponding to the operation gain B in FIGS. 8 and 9) at the time of a rear collision prediction or a rear collision, particularly at the time of a rear collision, is set to correspond to the operation gain of the airbag device 6. You can also. That is, as the acceleration at the time of collision detected by the G sensor S8 is larger,
Further, as the distance to the occupant J detected by the distance sensor S4 set for the airbag device shown in FIG. 2 increases, the operation gain of the airbag device 6 (the gain for determining the inflation speed, that is, the inflation pressure of the airbag) is increased. ) Is set to be large, but the larger the operating gain for the airbag, the larger the operating gain for the pretensioner can be set.

Each step (step group) or various members such as a sensor and a switch shown in the flowchart can be expressed by adding a name of a means to a higher-level expression of its function. Further, the function of each step (step group) can be expressed as a function of a control unit (functional unit) configured in the control unit. The purpose of the present invention is not limited to what is explicitly specified, but also implicitly includes providing what is substantially preferred or expressed as an advantage. Further, the present invention can be expressed as a control method.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention and also showing how a seat belt is pulled by a pretensioner.

FIG. 2 is a side view showing the embodiment of the present invention and also illustrating a state in which a seat belt is pulled by a pretensioner.

FIG. 3 is a plan view showing details around a retractor.

FIG. 4 is a side view of FIG. 3;

FIG. 5 is a diagram showing an example of a control system.

FIG. 6 is a flowchart showing one control example of the present invention.

FIG. 7 is a flowchart showing another control example of the present invention.

FIG. 8 is a characteristic diagram showing an example of setting an operation gain for determining an operation torque of a pretensioner.

FIG. 9 is a characteristic diagram showing another example of setting an operation gain for determining an operation torque of a pretensioner.

FIG. 10 is a side view showing an example of detecting the separation distance between the upper body of the occupant and the seat back.

FIG. 11 is a characteristic diagram used for detecting a separation distance in FIG. 10;

FIG. 12 is a characteristic diagram used for detecting a separation distance in FIG. 10;

FIG. 13 is a front view showing an example in which a distance sensor is provided in a headrest.

FIG. 14 is a front view showing another example in which a distance sensor is provided in the headrest.

FIG. 15 is a side view of FIG. 14;

FIG. 16 is a perspective view showing an example in which the separation distance between the occupant's upper body and the seat back is detected using a pressure switch.

FIG. 17 is a diagram collectively showing a relationship between an operation state of a pressure switch and an operation state of a pretensioner in the example of FIG. 16;

FIG. 18 is a side view showing an assumed occupant posture state according to the operation state of the pressure switch in the example of FIG. 16;

FIG. 19 is a side view showing an assumed occupant posture state according to the operation state of the pressure switch in the example of FIG. 16;

FIG. 20 is a side view showing an assumed occupant posture state according to the operation state of the pressure switch in the example of FIG. 16;

FIG. 21 is a side view showing an assumed occupant posture state according to the operation state of the pressure switch in the example of FIG. 16;

FIG. 22 is a perspective view showing another example of detecting the distance between the upper body of the occupant and the upper end of the seat back.

[Explanation of symbols]

1: Seat 2: Seat cushion 3: Seat back 4: Headrest 10: Three-point seat belt device 11: Seat belt 11 11a: Shoulder portion 11b: Wrap portion 12: Retractor (first connection portion) 13: Fixing device (No. 14: Fixing device (third connecting portion) 15: Buckle (second engaging portion) 16: Guide member 17: Tongue (first engaging portion) 24: Motor (drive source of pretensioner) 32: Pistons 61 to 64: Pressure switch (for detecting occupant attitude) 71: Roof S2: Sensor (detecting reclining angle) S3: Sensor (detecting seat slide position) S4: Sensor (detecting distance to occupant) S4A: Sensor (detecting distance) S5: Sensor (detection of occupant load applied to seat cushion) S6: Sensor (detection of occupant load applied to seat back) S7: Sa (for the rear 突予 knowledge) S8: G sensor (for infra 突検) S10: sensor (distance detection) 61 to 64: pressure switch (passenger posture detection) J: occupant U: control unit

Claims (9)

[Claims] 1. A vehicle occupant protection device having control means for operating a pretensioner for pulling a seat belt at the time of a rear collision prediction or a rear collision, wherein a separation distance between an upper body of the occupant and a seat back is detected. Distance detecting means, and restricting means for restricting the operation of the pretensioner by the control means when the distance detected by the distance detecting means is greater than a first predetermined value. Vehicle occupant protection system. 2. A vehicle occupant protection system comprising a control means for operating a pretensioner for pulling a seat belt at the time of a rear collision prediction or a rear collision, wherein a separation distance between an upper body of the occupant and a seat back is detected. Distance detecting means, and restricting means for restricting the operation of the pretensioner by the control means when the distance detected by the distance detecting means is smaller than a second predetermined value. Vehicle occupant protection system. 3. The vehicle occupant protection device according to claim 1, wherein the regulation by the regulation means is performed by inhibiting the operation of the pretensioner. 4. The vehicle according to claim 1, wherein the distance detecting means is a distance sensor provided near an upper end portion of the seat back to detect a distance to a back of an occupant. Characteristic vehicle occupant protection device. 5. The vehicle according to claim 1, wherein the distance detecting means includes a distance sensor provided in a passenger compartment in front of the occupant to detect a distance to the front of the occupant. An occupant protection device for a vehicle, wherein the separation distance between the upper body of the occupant and the seat back is determined based on the detected distance. 6. The detecting means according to claim 5, wherein said distance detecting means detects a sliding position of a seat, a reclining angle detecting means for detecting a reclining angle of said seat back, and said two detecting means. Based on the result, a first specific distance between the upper end of the seat back and the front of the vehicle compartment is determined.
A specific distance determining means, a pressure sensor provided on the seat cushion and detecting a magnitude of a load received from the occupant, a second sensor corresponding to the size of the occupant's head based on the load detected by the pressure sensor. A second specific distance determining means for determining a specific distance; and a distance between an upper body of the occupant and an upper end of the seatback based on the distance detected by the distance sensor, the first specific distance, and the second specific distance. And a calculating means for calculating a vehicle occupant. 7. The system according to claim 5, wherein the distance detecting means includes: a sliding position detecting means for detecting a sliding position of the seat; a reclining angle detecting means for detecting a reclining angle of the seat back; A specific distance determining means for determining a specific distance between the upper end portion of the seat back and the front of the passenger compartment based on the detection result; a pressure sensor provided on the seat cushion and detecting a magnitude of a load received from an occupant; Calculating means for calculating the distance between the upper body of the occupant and the upper end of the seatback from the distance detected by the distance sensor and the specific distance, wherein the occupant protection device for a vehicle is provided. . 8. The vehicle occupant protection system according to claim 6, wherein the distance sensor is provided at a front end of a roof of the vehicle body. 9. A three-point seat belt according to claim 1, wherein the seat belt is pulled out from a retractor connected to the vehicle body and connected to the vehicle body at both left and right ends of the seat. A vehicle, wherein the pretensioner includes an electric motor for applying a force in a retracting direction of a seat belt to the retractor, and wherein the control unit controls an operation of the electric motor. Occupant protection device.