JP2001039268A - Occupant crash protection device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase warning effect for collision forecast by making a first pretensioner act operation for mainly pulling the shoulder part of a seat belt to push the shoulder part of an occupant to a seat back when a collision is forecasted. SOLUTION: An electric motor 24 is fixed to the rear part of a case 21, that is, the opposite side of the drawing position of a seat belt, and is used for a first pretensioner for generating small pulling force, to be connected to a winding shaft line 22 via an electromagnetic clutch 25 and a speed reducer 26. When front or rear collisions are forecasted, an alarm and then the motor 24 are actuated to pull a seat belt by small pulling force. Pulling the seat belt by the motor 24 acts for pressing the shoulder part of an occupant rearward (to seat back), to extrernely increase the effect of collision forecast.

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 three-point 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:
With the first engaging portion engaging with the second engaging portion as a boundary, a shoulder portion that mainly restrains the shoulder portion of the occupant and a lap portion that mainly restrains the waist portion of the occupant can be distinguished.

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-6-28658
In Japanese Patent Publication No. 1 (1993), while a seat belt is pulled by a first pretensioner at the time of a collision prediction, when a collision actually occurs, the second pretensioner applies a larger pulling force than a pulling force by the first pretensioner. A tensioning seat belt is disclosed. In the publication described above, the first pretensioner is set to pull the second engagement portion, and the second pretensioner is provided on the retractor.

[0004]

According to the above-mentioned publication, when a collision is predicted, the seat belt is pulled through the second engagement portion, so that the shoulder portion and the lap portion of the seat belt are both pulled. Will be. However, the fact that the lap portion is pulled at the time of the collision prediction means that the occupant's waist tends to be strongly pulled toward the seat back,
There is room for improvement in ensuring sufficient operability of the accelerator pedal and brake pedal for collision avoidance. In addition, at the time of collision prediction, the lap portion only strongly presses the occupant's waist, and there is room for improvement in terms of warning of collision prediction.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a driver restraining an accelerator pedal and a brake pedal during a collision prediction while firmly restraining an occupant in a collision. It is an object of the present invention to provide a vehicle occupant protection device capable of satisfying both good operability and sufficient warning that there is a risk of collision.

In order to achieve the above object, the present invention adopts the following solution. That is, as described in claim 1 of the claims, the front end portion of the seat belt pulled out from the retractor connected to the vehicle body is connected to the vehicle body on one of the left and right sides of the seat, and at the intermediate portion of the seat belt. A vehicle occupant protection device including a three-point seat belt device in which an attached first engagement portion is removably engaged with a second engagement portion connected to a vehicle body on the other side of the seat.
A first pretensioner that is activated at the time of a collision prediction and applies a tensile force to the seat belt; and a second pretensioner that is activated at the time of a collision and applies a tensile force to the seat belt with a greater tension than the first pretensioner. Wherein the first pretensioner is set to pull a shoulder portion of the seat belt closer to the retractor than the first engagement portion toward the retractor, and the second pretensioner is The seat belt is set to be pulled from the side of the second engaging portion via the first engaging portion. Preferred embodiments on the premise of the above solution are as described in claim 2 and the following claims.

[0006]

According to the first aspect of the present invention, when a collision is predicted, the first pretensioner mainly pulls the shoulder portion of the seat belt, and has the effect of pressing the occupant's shoulder against the seat back. In addition, the occupant shoulder, which is often separated from the seat back, is displaced toward the seat back, and the warning effect of collision prediction can be enhanced. In addition, since the lap portion of the seat belt is not pulled so strongly from the first pretensioner, the occupant is prevented or restrained from significantly changing the attitude position with respect to the accelerator pedal and the brake pedal, and good pedal operation for avoiding a collision is achieved. Nature can be secured. Of course,
At the time of a collision, both the shoulder portion and the lap portion of the seat belt are sufficiently pulled by the second pretensioner with a large pulling force, so that the occupant can be sufficiently restrained against the seat. In addition to the above, since the first pretensioner and the second pretensioner have an arrangement relationship spaced apart from each other, the first pretensioner and the second pretensioner are preferable in terms of vehicle mountability as compared with the case where they are arranged close to each other.

According to claim 2, the collision prediction is liable to be erroneously determined, but even if the collision prediction is erroneously determined,
Then, the first pretensioner can be operated at the time of normal collision prediction. Although the second pretensioner is allowed to operate only once, a second pretensioner that generates a large tensile force can be selected. According to claim 3, a specific operation method of each pretensioner is provided. According to the fourth aspect, when the seat belt is pulled by the second pretensioner with a large tensile force, the seat belt is reliably prevented from being pulled out from the retractor, and the occupant restraint using the second pretensioner is reliably performed. It can be carried out.

According to the fifth aspect, the second pretensioner secures the tension portion of the seat belt as long as possible, which is preferable for more effective restraint of the occupant. According to the sixth aspect, the locking means and the first pretensioner can be centrally arranged near the retractor while obtaining the effect corresponding to the fifth aspect.

[0009]

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.

A three-point seat belt device 10 for a 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 fixed box 14 is fixed to the vehicle body (in the embodiment, a floor panel) at a low position immediately to the left of the seat cushion 2, and a buckle 15 is connected to the fixed box 14 as described later.

A guide member 16 is fixed to the vehicle body (B pillar in the embodiment) at a position slightly higher than the seatback 4 in the normal use state among the high positions on the right side of the seat 1. The seat belt 11 pulled out from the retractor 12 once extends upward, and is slidably inserted through the guide member 16, and the distal end thereof is fixed to the vehicle body as described above. 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 forms a first engaging portion, and the buckle 15 forms a second engaging portion.

When the tongue 17 is engaged with the buckle 15 with the seat belt 11 positioned in front of the occupant J seated on the seat 1, the occupant J is seated 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 three points of the retractor 12, the fixture 13, and the buckle 15 (fixed box 14) via the seat belt 11. As described above, the retractor 12 serves as a first connection part to the vehicle body, the fixture 13 serves as a second connection part to the vehicle body, and the buckle 15 serves as a third connection part to the vehicle body. Seat belt 1
When the occupant J is restrained by the occupant 1, a portion of the seat belt 11 that extends from the tongue 17 (buckle 15) to the guide member 16 becomes a shoulder portion 11a that mainly restrains the occupant J from the shoulder to the chest. The portion that extends over the fixture 13 is the wrap portion 11b that mainly restrains the waist of the occupant J.

The retractor 12 is equipped with a first pretensioner (pretensioner device) and locking means. The details of the retainer 12 will be described below with reference to FIGS.
This will be described with reference to FIG. 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 spring.
Is applied to the winding axis 22 (winding axis).

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 first pretensioner that generates a small tensile force, and is connected to the winding axis 22 via an electromagnetic clutch 25 and a speed reducer 26. Locking means 27 is attached to the case 11 on the side opposite to the spring mechanism 23.
This locking means 27, as is known,
1 is pulled at a speed greater than a predetermined speed, that is, when the winding axis 22 is rotated in the seat belt withdrawal direction at a speed higher than a predetermined rotation speed, the rotation of the winding axis 22 is locked, and the seat belt is locked. 11 to lock the drawer. However, in the embodiment, the lock means 27 is separately equipped with an electric motor as a drive source, and is configured to forcibly lock when receiving a predetermined operation signal.

Next, with reference to FIGS. 5 and 6, the details of the attachment portion of the buckle 15 to the vehicle body will be described, including the second pretensioner provided here. First, the above-described fixing box 14 has an elongated case 31 fixed to the vehicle body. A piston 32 is provided in the case 31.
Is slidably fitted, and one end of a connection cable 33 is fixed to the piston 32. Connection cable 33
Is extended out of the case 31, and the buckle 15 is connected to the end thereof. An inflator 34 is provided in the case 31. The inflator 34 is of an explosive type, is detonated when an operation signal is given, and generates a large gas pressure in the case 31. The inflator 34 is a main component of the second pretensioner for generating a large tensile force.

The piston 32 which has received the gas pressure generated by igniting the inflator 34 is displaced from the state shown in FIG. 5 to the state shown in FIG. 6, and the connecting cable 33, that is, the buckle 15 is pulled with a large tensile force. Pull. The tensile force of the piston 32 generated due to the explosion of the inflator 34 is sufficiently larger than the tensile force of the seat belt 11 by the motor 24 as the first pretensioner described above. In the case 31, a lock member 35 using an eccentric cam is rotatably disposed about a mounting shaft 36. The lock member 35 is disposed at a position where the connection cable 33 is bent. In a state after the operation of the inflator 34 in FIG. 6, a lock claw portion 35 a formed on the peripheral surface of the lock member 35 acts on the connection cable 33, The connection cable 33 is locked from being pulled out of the case 31.

FIG. 7 shows a control system. In the figure, U is a control unit constituted by using a microcomputer. Signals from various sensors S1 to S5 are input to the control unit U. The sensor S1 is
It is a G sensor and detects a collision (for detecting frontal collision and rear collision). The sensor S2 is a front collision prediction sensor, and predicts a front collision. The front collision prediction sensor S2 is configured by using, for example, a radar that detects an obstacle in front of the vehicle, and is highly likely to collide based on, for example, the distance to the obstacle and the relative speed detected by the radar. Whether or not this is the case is determined by the control unit U. The sensor S3 is a rear collision prediction sensor, and predicts a rear collision. After this, the collision prediction sensor S
3 is configured using, for example, a radar that detects an obstacle behind the vehicle, and controls whether the possibility of collision is high based on the distance to the obstacle and the relative speed detected by the radar, for example. Determined by unit U.

The sensor S4 is an occupant detection sensor for detecting whether or not the occupant J is seated on the seat 1. For example, the sensor S4 is provided on the seat cushion 2 of the seat 1 and is activated when the occupant is seated. It is composed of a pressure-sensitive switch. The switch S5 determines that the occupant J has the seat belt 11
Is a switch for detecting whether or not the buckle 15 is properly mounted. For example, the switch is mounted on the buckle 15 and is turned ON when the tongue 17 is properly engaged with the buckle 15.

The devices controlled by the control unit U include a pretensioner (motor 24, inflator 34), an airbag 6, a lock means 27 as a seat belt clamp (motor mounted on), a lamp,
An alarm 41 (preferably an alarm by sound) including a buzzer and the like, and a headrest drive motor 42 are included. The headrest drive motor 42 is for driving the headrest 4 forward, that is, in a direction approaching the head of the occupant J. More specifically, for example, the headrest 4 is attached to the seatback 3 so as to be displaceable forward by a predetermined amount, and the headrest 4 is driven forward by, for example, a motor 42 provided on the seatback 3. Further, a predetermined portion of the headrest 4 where the head of the occupant J comes into contact is divided into other portions, and the motor 42 is driven so that the predetermined portion is driven forward. Can also.

The outline of the control by the control unit U is as follows. First, when a front collision is detected, the airbag 6 is actuated, and the inflator 34 is detonated in a state where the pulling-out of the seat belt 11 by the locking means 27 is locked. It is restrained by the seat 1. When a rear collision is detected, the headrest 4 is displaced forward by a predetermined amount, and then the seat belt 1 is locked by the locking means 27 as in the case of a front collision.
With the drawer 1 locked, the inflator 34 is detonated, and the occupant J is restrained by the seat 1 with a large tensile force. When a front collision or a rear collision is predicted, the alarm 24 is operated, and then the motor 24 is operated, and the seat belt 11 is pulled with a small pulling force. The pulling of the seat belt 11 by the motor 24 serves to press the shoulder of the occupant J rearward (seat back 3), and the effect of collision prediction is extremely high.

Next, the control by the control unit U will be described in detail with reference to flowcharts shown in FIGS. 8 and 9. In the following description, Q indicates a step. First, at Q1 in FIG. 8, after the output of the occupant detection sensor S4 is read, at Q2, the sensor S4
It is determined whether or not the occupant is seated on the seat 1 based on the output state of (1). If the determination in Q2 is YES, Q
After reading the signal from the G sensor S1 in 3, it is determined in Q4 whether a front collision has occurred based on the output of the G sensor S1.

If the determination in Q4 is YES, first, in Q5, the airbag device 6 is operated. Then, Q6
After the operation state of the seatbelt switch S5 is read in, it is determined in Q7 whether or not the seatbelt 11 is worn based on the operation state of the switch S5. If the determination in Q7 is YES, Q
At 8, after the locking means 27 is operated to prevent the seat belt 11 from being pulled out of the retractor 12 (clamp), at q 9, the inflator 34 is operated and the buckle 15 is pulled with a large tensile force. As a result, the occupant J is tightly restrained by the seat 1 with the shoulder portion 11a and the wrap portion 11b of the seat belt 11 both pulled (see the broken line in FIG. 1).

If NO in Q4, it is determined in Q10 whether a rear collision has been detected. This Q
If the determination in step 10 is YES, in step Q11, the motor 42 is operated to prevent
Is moved forward, and the processing after Q6 is performed. If the determination in Q7 is NO, the process ends without obtaining the processes in Q8 and Q9.

When the determination in Q2 is NO, or when Q10
If the determination is NO, the process moves to Q21 in FIG. 9 respectively. In Q21, after the output from the front collision prediction sensor S2 is read, it is determined in Q22 whether the possibility of a front collision is large based on the output of the sensor S2. If the determination in Q22 is YES, in Q23, after the alarm 41 is operated, in Q24, the motor 24 is operated, and the seat belt 11 is pulled with a small pulling force (the wavy line state in FIG. 2). reference). Motor 2
4, the pulling of the seat belt 11 is mainly the pulling of the shoulder portion 11a, whereby the shoulder of the occupant J is pressed against the seat back 3, and the collision prediction is effectively performed on the occupant J. become.

If NO in Q22, Q25
After the output from the rear collision prediction sensor S3 is read in, it is determined in Q26 whether or not the possibility of a rear collision is large based on the output of the sensor S3. This Q
If the determination in step 26 is YES, the processing after Q23 is performed. If the determination in Q26 is NO, in Q27,
After the operation of the motor 24 is released, the process returns.

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. The motor 24 is used as a drive source of the first pretensioner.
Can be selected as appropriate, such as using a hydraulic cylinder. The drive source of the second pretensioner can be appropriately selected, for example, using a fluid type (particularly, a hydraulic type cylinder for securing a large tensile force) instead of the inflator 34. The locking means 27 for preventing the seat belt 11 from being pulled out of the retractor 12 is preferably provided near the retractor 11, that is, it is preferably mounted on the retractor 12 itself as shown in the embodiment, or provided immediately adjacent thereto. It can also be provided far apart from the retractor 12 (for example, near the guide member 16).
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.

Each step (step group) shown in the flowchart or various members such as a sensor and a switch 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. Furthermore, the present invention can be expressed as a method.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing the embodiment of the present invention and also illustrating a state in which a seat belt is pulled by a first 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 side sectional view showing an example of a second pretensioner part.

FIG. 6 is a side sectional view showing a state after the second pretensioner has been operated from the state of FIG. 5;

FIG. 7 is a diagram showing an example of a control system.

FIG. 8 is a flowchart illustrating a control example.

FIG. 9 is a flowchart illustrating a control example.

[Explanation of symbols]

1: Seat 2: Seat cushion 3: Seat back 4: Headrest 6: Airbag device 10: Seat belt device 11: Seat belt 11 11a: Shoulder portion 11b: Wrap portion 12: Retractor (first connecting portion) 13: Fixing device (Second connecting part) 14: Fixed box (third connecting part, second pretensioner) 15: Buckle (second engaging part) 16: Guide member 17: Tongue (first engaging part) 24: Motor ( 27: locking means 32: piston 33: connecting cable 34: inflator (drive source of second pretensioner) J: occupant U: control unit

Claims (6)

[Claims] A front end of a seat belt pulled out of a retractor connected to a vehicle body is connected to the vehicle body on one of left and right sides of the seat, and a first engaging portion attached to an intermediate portion of the seat belt is provided on the seat belt. In a vehicle occupant protection device having a three-point seat belt device detachably engaged with a second engagement portion connected to a vehicle body on the other side, the vehicle is actuated when a collision is predicted, and the seat belt is pulled. And a second pretensioner that is activated at the time of a collision and applies a tensile force to the seat belt with a greater tension than the first pretensioner. The first pretensioner includes: A shoulder portion of the seat belt that is closer to the retractor than the first engagement portion is set to be pulled toward the retractor; The occupant protection device for a vehicle according to claim 1, wherein the shoulder is configured to pull the seat belt from the side of the second engagement portion via the first engagement portion. 2. The vehicle occupant according to claim 1, wherein the first pretensioner is operable a plurality of times, and the second pretensioner is not operable a plurality of times. Protective equipment. 3. The vehicle occupant protection system according to claim 2, wherein the first pretensioner is of an electric type, and the second pretensioner is of an explosive type. 4. A locking device according to claim 1, further comprising a locking means for preventing the seat belt from being pulled out of the retractor when the second pretensioner is operated. An occupant protection device for a vehicle. 5. The vehicle occupant protection device according to claim 4, wherein the locking means is set to act on the seat belt near the retractor. 6. The vehicle according to claim 3, wherein the first pretensioner is set to act on a winding shaft of the retractor, and the second pretensioner is configured to move the second engagement portion to a vehicle body. A second engaging portion provided on the connecting portion and configured to pull the second engaging portion; and when the second pretensioner is operated, the second engaging portion acts on a winding shaft of the retractor to pull out the seat belt from the retractor. An occupant protection device for a vehicle, comprising: locking means for preventing the vehicle occupant from occupying.