JP2017124680A - Occupant protection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an occupant protection device that is able to reduce influence of a driving operation of an occupant even if an amount of movement of the upper body of the occupant becomes relatively large.SOLUTION: An occupant protection device 10 comprises: a webbing belt 20 that restrains the upper body of an occupant seated on a vehicle seat of a driver seat; a pretensioner 22 that further applies tension to the webbing belt 20 by being actuated; an electrostatic capacitive sensor 18 that detects a distance between the seat back of the vehicle seat and the occupant; and an ECU 12 that controls the pretensioner 22 such that if collision of the own vehicle is detected or estimated, the pretensioner 22 is actuated, and if a distance detected by the electrostatic capacitive sensor 18 is longer than a predetermined first threshold, tension applied to the webbing belt 20 is decreased compared to the case where the distance is equal to or shorter than the first threshold value.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an occupant protection device for protecting an occupant of a vehicle.

  2. Description of the Related Art Conventionally, there has been proposed a technique for pulling the tip of a buckle or a webbing belt in a suitable direction according to the seating posture of an occupant.

  For example, in Patent Document 1, a webbing belt that restrains an occupant seated on a vehicle seat, and a buckle or a webbing belt tip that is provided with a tongue provided at an intermediate portion of the webbing belt is directly or indirectly on one side. The other side is rotatably connected to the vehicle seat side or the vehicle body side via a support shaft whose axial direction is along the seat width direction, and is pulled to one side of the support shaft. A seat belt device including a link member provided with a portion is disclosed. Further, the seat belt device includes a pretensioner body that, when operated, pulls the pulled portion toward a pulling position set below the link member, the pulled portion, the support shaft, and the It is avoided that the rotation of the link member around the support shaft is hindered by the operation of the pretensioner body in a neutral state in which the tension positions are linearly arranged when viewed from the sheet width direction.

JP 2011-173462 A

  However, when the pretensioner is operated in a state where the back of the occupant is not in contact with the seat back when the collision of the host vehicle is detected or predicted, the amount of movement of the occupant's upper body relative to the rear of the vehicle becomes relatively large. . For example, as shown in FIG. 7A, when the collarbone of the occupant D seated in the driver's seat is ahead of the vehicle with respect to the planes A and B and the back of the occupant D is not in contact with the seat back 200, the amount of movement is It becomes relatively large. In this case, when the webbing belt 202 is pulled in, a force toward the rear side of the vehicle is applied to the upper body of the occupant D. Further, in this case, when the occupant D tries to stay in place or the occupant D moves due to sudden braking, a force toward the vehicle front side is applied to the upper body of the occupant D as an inertial force. The force toward the vehicle rear side moves the upper body of the occupant D toward the vehicle rear side (seat back side) against the inertial force. Here, the plane A is a plane that connects the shoulder anchor 204 and the foremost end of the pelvis of the occupant D, and the plane B is a plane that connects the shoulder anchor 204 and the buckle anchor 206. In FIG. 7A, the force with which the webbing belt 202 is pulled is a force in the direction of arrow F1, the force to the rear side of the vehicle applied to the upper body of the occupant D is the force in the direction of arrow F2, and the inertial force is The force in the direction of arrow F3.

  Therefore, as shown in FIG. 7B, when the force toward the rear side of the vehicle generated by pulling in the webbing belt 202 is larger than the inertial force of the occupant D, the upper body of the occupant D moves backward toward the rear side of the vehicle.

  When the amount of movement of the occupant's upper body becomes relatively large, the occupant's hands and arms may move away from the steering wheel, which may affect the driving operation.

  The present invention has been made in consideration of the above facts, and an object of the present invention is to reduce the influence on the driving operation of the occupant even when the amount of movement of the occupant's upper body becomes relatively large.

  In order to achieve the above-mentioned object, the invention according to claim 1 further applies tension to the webbing belt by operating with a webbing belt that restrains an upper body of an occupant seated on a vehicle seat of a driver's seat. A pretensioner, a detection unit that detects a distance between the seat back of the vehicle seat and the occupant, and activates the pretensioner when a collision of the host vehicle is detected or predicted, and the detection unit The tension applied to the webbing belt is smaller when the distance detected by the detection unit is longer than a predetermined first threshold than when the distance detected by the detection unit is less than or equal to the first threshold. And a control unit for controlling the pretensioner.

  According to the first aspect of the present invention, when the pretensioner is operated, tension is further applied to the webbing belt that restrains the upper body of the passenger seated on the vehicle seat of the driver's seat. Further, the distance between the seat back of the vehicle seat and the occupant is detected by the detection unit. When the control unit detects or predicts a collision of the host vehicle, the pretensioner is activated, and when the distance detected by the detection unit is longer than a predetermined first threshold, the detection unit The pretensioner is controlled so as to reduce the tension applied to the webbing belt as compared with the case where the distance detected by the above is less than or equal to the first threshold value. Therefore, even when the amount of movement of the occupant's upper body is relatively large, the influence on the driving operation of the occupant can be reduced.

  The invention according to claim 2 is the invention according to claim 1, wherein the control unit predicts a collision of the host vehicle and the distance detected by the detection unit is longer than the first threshold value. In addition, control is performed to make the timing for starting the operation of the pretensioner faster than when the distance detected by the detection unit is equal to or less than the first threshold value. That is, when the tension applied to the webbing belt is reduced, the timing for starting the operation of the pretensioner is advanced. Therefore, even when the tension applied to the webbing belt is reduced, the occupant's restraint can be enhanced.

  The invention according to claim 3 is the pretensioner according to the invention according to claim 1 or 2, wherein the control unit has a pretensioner when the distance detected by the detection unit is equal to or greater than a second threshold greater than the first threshold. Control to prohibit the operation of. Thereby, when the movement amount of the occupant's upper body is equal to or greater than a predetermined amount, the operation of the pretensioner is prohibited, so that the influence on the driving operation can be reduced.

  According to a fourth aspect of the present invention, there is provided the webbing belt according to any one of the first to third aspects, wherein the detection unit restrains the occupant when the host vehicle is viewed from the front. The distance between the seat back and the occupant is detected within a range where the seat back and the seat back overlap. Thereby, the amount of movement of the occupant's upper body can be detected with high accuracy.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the tension applied to the webbing belt by the control unit as the distance detected by the detection unit increases. The pretensioner is controlled so as to make it smaller. Thereby, the influence with respect to a driving | operation operation | movement of a passenger | crew can be reduced according to the distance of a seat back and a passenger | crew.

  As described above, according to the present invention, it is possible to reduce the influence on the driving operation of the occupant even when the amount of movement of the occupant's upper body is relatively large.

It is a block diagram which shows an example of schematic structure of the passenger | crew protection apparatus which concerns on each embodiment. It is a front view which shows an example of schematic structure of the vehicle seat which concerns on each embodiment. It is a flowchart which shows an example of the flow of the process performed with the passenger | crew protection apparatus which concerns on 1st Embodiment. It is a side view which shows an example of the state which the passenger | crew and seat back which concern on each embodiment contacted. It is a side view showing an example of the state where the crew member and seat back concerning each embodiment are not in contact. It is a flowchart which shows an example of the flow of the process performed with the passenger | crew protection apparatus which concerns on 2nd Embodiment. It is a flowchart which shows an example of the flow of the process performed with the passenger | crew protection apparatus which concerns on 3rd Embodiment. It is a side view showing an example of the state before movement of the upper body when the amount of movement of the upper body of the occupant relative to the rear of the vehicle increases. It is a side view showing an example of the state after movement of the upper body when the amount of movement of the upper body of the occupant relative to the rear of the vehicle increases.

  DETAILED DESCRIPTION Hereinafter, exemplary embodiments for carrying out the present invention will be described in detail with reference to the drawings. Note that an arrow FR appropriately shown in each drawing indicates the vehicle front side, an arrow UP indicates the vehicle upper side, and an arrow OUT indicates the vehicle width direction outer side.

[First Embodiment]
First, with reference to FIG.1 and FIG.2, the structure of the passenger | crew protection device 10 which concerns on this Embodiment is demonstrated. As shown in FIG. 1, the occupant protection device 10 includes an ECU (Electronic Control Unit) 12, a collision detection sensor 14, a collision prediction sensor 16, a capacitance sensor 18, a webbing belt 20, and a pretensioner 22.

  The ECU 12 includes a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. In addition, a collision detection sensor 14, a collision prediction sensor 16, a capacitance sensor 18, and a pretensioner 22 are connected to the ECU 12.

  The collision detection sensor 14 is a sensor used for the collision detection between the host vehicle and the collision target by the ECU 12, and outputs a signal corresponding to the deformation amount of the vehicle bumper caused by the collision with the collision target, for example. Based on the signal input from the collision detection sensor 14, the ECU 12 detects that the host vehicle and the collision target have collided. In addition, as the collision detection sensor 14, a pressure sensor, an acceleration sensor, etc. are applicable, for example.

  The collision prediction sensor 16 is a sensor used for the collision prediction between the host vehicle and the collision target by the ECU 12, and outputs a signal corresponding to the distance between the host vehicle and the collision target to the ECU 12, for example. Based on the signal input from the collision prediction sensor 16, the ECU 12 predicts that a collision between the host vehicle and the collision target is unavoidable. As the collision prediction sensor 16, for example, a millimeter wave radar or a lidar (LIDER: Laser Imaging Detection and Ranging) can be applied.

  The electrostatic capacity sensor 18 is provided on a seat back 34 (see FIG. 2), which will be described later. Based on the change in electrostatic capacity, the electrostatic capacity sensor 18 is provided between the seat back 34 and the back of the occupant seated on the vehicle seat 30 in the driver's seat. The distance is detected, and a signal corresponding to the detected distance is output to the ECU 12. With reference to FIG. 2, the installation position of the capacitance sensor 18 will be described. In FIG. 2, the webbing belt 20 is indicated by a broken line in order to avoid complications. As shown in FIG. 2, the vehicle seat 30 includes a headrest 32, a seat back 34, a side support 36, and a seat cushion 38.

  The electrostatic capacity sensor 18 is provided in the upper left part of the seat back 34 when viewed from the front, and the webbing belt 20 and the seat back 34 in a state of restraining the occupant overlap when the host vehicle is viewed from the front side of the vehicle. Within the range, the distance between the seat back 34 and the back of the occupant (more specifically, the scapula outside the occupant in the vehicle width direction) is detected. In the present embodiment, a case where the distance between the seat back 34 and the occupant is detected using a capacitance sensor will be described, but the present invention is not limited to this. For example, the distance between the seat back 34 and the occupant may be detected using an imaging result of an in-vehicle camera that images the seat back 34 and the occupant from above the vehicle.

  The webbing belt 20 is a belt-like member that is attached to an occupant seated on the vehicle seat 30 of the driver's seat and restrains the upper body of the occupant. One end of the webbing belt 20 in the longitudinal direction is attached to the side of the seat cushion 38 on the outer side in the vehicle width direction via an anchor plate. The other end portion of the webbing belt 20 in the longitudinal direction is wound around the retractor so as to be drawn out.

  Further, the intermediate portion of the webbing belt 20 is inserted and folded back through a shoulder anchor provided at an upper portion on the outer side in the vehicle width direction. Then, the tongue plate into which the webbing belt 20 is inserted is engaged with a buckle provided on the inner side in the vehicle width direction of the seat cushion 38, so that the webbing belt 20 is attached to a passenger seated on the vehicle seat 30.

  The pretensioner 22 is provided on the retractor, and operates to apply further tension to the webbing belt 20 to wind the webbing belt 20 around the retractor. Here, the tension means a force that pulls the webbing belt 20 around the retractor in the winding direction. Further, the pretensioner 22 is configured to be able to change the tension applied to the webbing belt 20 under the control of the ECU 12.

  The configuration of the pretensioner 22 is not particularly limited as long as the tension applied to the webbing belt 20 can be changed. For example, the pretensioner 22 may be a member configured to apply tension to the webbing belt 20 by driving a motor. In this case, a mode in which the tension applied to the webbing belt 20 is changed by changing the driving amount of the motor by the ECU 12 is exemplified.

  For example, the pretensioner 22 may be a member configured to generate gas by operating an ignition device and apply tension to the webbing belt 20 by the pressure of the generated gas. In this case, the ECU 12 may be configured to change the tension applied to the webbing belt 20 by reducing the pressure of the generated gas using a pressure reducing mechanism or the like.

  In the present embodiment, the capacitance sensor 18 is an example of the detection unit of the present invention, and the ECU 12 is an example of the control unit of the present invention.

  Next, with reference to FIG. 3, the operation of the occupant protection device 10 according to the present embodiment will be described. FIG. 3 is a flowchart illustrating an example of a flow of processing executed by the ECU 12 of the occupant protection device 10 according to the present embodiment. In the present embodiment, the ECU 12 executes a program stored in advance in the ROM in the process shown in FIG. The processing shown in FIG. 3 is started when, for example, an ignition switch (not shown) is turned on.

  In step 100 of FIG. 3, the ECU 12 determines whether or not the own vehicle and the collision target have collided, or whether or not the collision between the own vehicle and the collision target is unavoidable. Specifically, the ECU 12 acquires the output signal of the collision detection sensor 14 and determines whether or not the host vehicle and the collision target have collided based on the acquired output signal. Moreover, ECU12 acquires the output signal of the collision prediction sensor 16, and determines whether the collision with the own vehicle and a collision object is unavoidable based on the acquired output signal. The ECU 12 repeatedly executes step 100 if the determination in step 100 is negative, and proceeds to step 102 if the determination is affirmative.

  In step 102, the ECU 12 obtains the distance between the seat back 34 detected by the capacitance sensor 18 and the back of the occupant. In the next step 104, the ECU 12 determines whether or not the seat back 34 and the back of the occupant are in contact based on the distance acquired in step 102. Specifically, the ECU 12 determines whether or not the distance acquired in step 102 is equal to or less than a predetermined first threshold value TH1. In this case, the first threshold value TH1 may be a value obtained in advance as an upper limit value of a value in which the seat back 34 and the back of the occupant are in contact with each other by an experiment using an actual vehicle. If the determination in step 104 is affirmative, the ECU 12 proceeds to step 106. FIG. 4A shows an example of the sitting posture of the occupant when the determination in step 104 is affirmative.

  In step 106, the ECU 12 operates the pretensioner 22. Further, the ECU 12 controls the pretensioner 22 to apply a tension larger than the tension applied in step 108, which will be described later, to the webbing belt 20, thereby ending the processing routine after winding the webbing belt 20 around the retractor. To do. Specifically, as an example, the ECU 12 controls the pretensioner 22 to apply the maximum allowable tension to the webbing belt 20.

  On the other hand, when the determination in step 104 is negative, the ECU 12 proceeds to step 108. FIG. 4B shows an example of the sitting posture of the occupant when the determination at step 104 is negative. In step 108, the ECU 12 operates the pretensioner 22. Further, the ECU 12 controls the pretensioner 22 to apply a tension smaller than the tension applied in step 106 to the webbing belt 20, thereby winding the webbing belt 20 around the retractor, and then ends the present processing routine.

[Second Embodiment]
Hereinafter, the second embodiment of the present invention will be described in detail. Note that the configuration of the occupant protection device 10 according to the present embodiment is the same as that of the first embodiment (see FIGS. 1 and 2), and thus the description thereof is omitted here.

  With reference to FIG. 5, the operation of occupant protection device 10 according to the present embodiment will be described. FIG. 5 is a flowchart illustrating an example of a flow of processing executed by the ECU 12 of the occupant protection device 10 according to the present embodiment. Further, steps in FIG. 5 that execute the same processing as in FIG. 3 are denoted by the same step numbers as in FIG. 3, and description thereof is omitted.

  In step 101 of FIG. 5, the ECU 12 determines whether or not a collision between the host vehicle and the collision target is unavoidable. Specifically, the ECU 12 acquires an output signal of the collision prediction sensor 16, and determines whether or not a collision between the host vehicle and the collision target is inevitable based on the acquired output signal. If this determination is negative, the ECU 12 repeatedly executes step 101, and if it is positive, the ECU 12 proceeds to step 102.

  If the determination in step 104 is affirmative, the ECU 12 proceeds to step 105. If the determination is negative, the ECU 12 proceeds to step 107A. In step 105, the ECU 12 waits for a predetermined period T1, and then proceeds to step 106. On the other hand, in step 107A, the ECU 12 waits for a period T2 that is predetermined as a period shorter than the period T1, and then proceeds to step 108. In addition, what is necessary is just to apply the period etc. in time for protection of a passenger | crew by the experiment etc. which used the actual machine of the vehicle for the periods T1 and T2. Further, the period T2 may be 0 (zero).

  As described above, in the present embodiment, when the collision of the host vehicle is predicted and the distance detected by the capacitance sensor 18 is longer than the first threshold value TH1, the distance is equal to or less than the first threshold value TH1. The timing for starting the operation of the pretensioner 22 is made earlier than in the case of the above. Therefore, even when the tension applied to the webbing belt 20 is reduced, the occupant's restraint can be enhanced.

[Third Embodiment]
Hereinafter, the third embodiment of the present invention will be described in detail. Note that the configuration of the occupant protection device 10 according to the present embodiment is the same as that of the first embodiment (see FIGS. 1 and 2), and thus the description thereof is omitted here.

  With reference to FIG. 6, the operation of occupant protection device 10 according to the present embodiment will be described. FIG. 6 is a flowchart illustrating an example of a flow of processing executed by the ECU 12 of the occupant protection device 10 according to the present embodiment. Further, steps in FIG. 6 that execute the same processing as in FIG. 3 are denoted by the same step numbers as in FIG. 3, and description thereof is omitted.

  If the determination at step 104 in FIG. 6 is negative, the ECU 12 proceeds to step 107B. In step 107B, the ECU 12 determines whether or not the distance acquired in step 102 is greater than or equal to a second threshold TH2 that is predetermined as a value greater than the first threshold TH1. As the second threshold value, a value obtained in advance as a lower limit value of a value that prohibits the restraining of the occupant by the webbing belt 20 by an experiment using an actual vehicle may be applied. The ECU 12 returns to step 100 if the determination in step 107B is affirmative, but proceeds to step 108 if it is negative.

  As described above, in the present embodiment, when the distance between the seatback 34 detected by the capacitance sensor 18 and the occupant is equal to or greater than the second threshold value TH2, which is greater than the first threshold value TH1, the operation of the pretensioner 22 is prohibited. ing. Therefore, the influence on the driving operation can be reduced. Note that the third embodiment and the second embodiment may be combined.

  In each of the above embodiments, the case where the tension applied to the webbing belt 20 is changed in two stages by operating the pretensioner 22 is described, but the present invention is not limited to this. For example, the tension may be changed in a plurality of stages including three or more stages. As a form example in this case, a form in which the tension applied to the webbing belt 20 is reduced by operating the pretensioner 22 as the distance detected by the capacitance sensor 18 becomes longer is exemplified.

  Moreover, although each said embodiment demonstrated the case where the distance of the seat back 34 and the scapula of a passenger | crew's vehicle width direction outer side was detected, it is not limited to this. For example, it is good also as a form which detects the distance of seat back 34 and parts other than a scapula outside a passenger | crew's width direction.

  In each of the above-described embodiments, the case where the capacitance sensor 18 is provided in the upper left portion of the seatback 34 as viewed from the front is described, but the present invention is not limited to this. For example, the capacitance sensor 18 may be provided at another position of the seat back 34.

  Moreover, although the process performed by ECU12 in each said embodiment was demonstrated as a software process performed by running a program, it is good also as a process performed by hardware. Moreover, the process performed by ECU12 is good also as a process performed combining both software and hardware. Further, the program stored in the ROM may be stored in various storage media and distributed.

  Moreover, although each said embodiment demonstrated the example which comprises ECU12 with one microcomputer, it is not limited to this. Any function of the ECU 12 may be included in another ECU.

  Furthermore, the present invention is not limited to the above-described embodiments, and it is needless to say that the present invention can be variously modified and implemented in addition to the above-described embodiments without departing from the gist thereof.

10 occupant protection device 12 ECU (control unit)
18 Capacitance sensor (detector)
20 Webbing belt 22 Pretensioner 30 Vehicle seat 34 Seat back

Claims (5)

A webbing belt that restrains the upper body of an occupant seated in the vehicle seat of the driver's seat;
A pretensioner for further applying tension to the webbing belt by operating;
A detection unit for detecting a distance between a seat back of the vehicle seat and the occupant;
When the collision of the host vehicle is detected or predicted, the pretensioner is actuated, and when the distance detected by the detection unit is longer than a predetermined first threshold, the detection unit detects the collision. A control unit that controls the pretensioner so that the tension applied to the webbing belt is smaller than when the distance is equal to or less than the first threshold value;
An occupant protection device. When the collision of the host vehicle is predicted and the distance detected by the detection unit is longer than the first threshold, the control unit is configured such that the distance detected by the detection unit is equal to or less than the first threshold. The occupant protection device according to claim 1, wherein control is performed to make the timing for starting the operation of the pretensioner faster than in some cases. The occupant protection device according to claim 1 or 2, wherein the control unit performs control to prohibit the operation of the pretensioner when the distance detected by the detection unit is equal to or greater than a second threshold value that is greater than the first threshold value. . The detection unit detects a distance between the seat back and the occupant within a range where the webbing belt in a state where the occupant is restrained and the seat back overlap when the host vehicle is viewed from the front. The occupant protection device according to claim 3. The occupant according to any one of claims 1 to 4, wherein the control unit controls the pretensioner so as to reduce a tension applied to the webbing belt as the distance detected by the detection unit increases. Protective device.