JP7365230B2 - seat belt device - Google Patents

Description

The present invention relates to a seat belt device for restraining an occupant seated in a vehicle seat.

For example, three-point seatbelts are widely used to restrain occupants seated in the seats of vehicles such as automobiles and to prevent injuries in the event of a collision.
The three-point seat belt includes a lap belt section that extends in the vehicle width direction along the front surface of the occupant's waist, and a shoulder belt section that extends obliquely along the front surface of the occupant's chest.

As a conventional technology related to three-point seat belts, for example, Patent Document 1 discloses that in order to reduce the gap between the shoulder webbing and the occupant and improve occupant restraint when the webbing is activated, when the occupant wears the webbing, the buckle drive device The buckle device is moved inward in the width direction of the vehicle to reduce the gap between the shoulder webbing and the occupant, and the shoulder webbing is moved overall upwards of the vehicle, which improves the occupant restraint of the shoulder webbing. It is stated that it can be improved.

Japanese Patent Application Publication No. 2007-196881

Seat belt devices are an effective means for reducing chest injuries to occupants and secondary collisions with other parts in the vehicle cabin in frontal collisions.
However, in the case of a three-point seatbelt with a diagonal shoulder belt, the tongue side (lower side) of the shoulder belt may be affected by movements such as forward leaning of the occupant's upper body or the operation of the pretensioner. When the webbing rises upward relative to the chest due to an increase in the tension of the webbing, it may compress the vicinity of the ribs upward and generate bending force on the ribs.
In view of the above-mentioned problems, an object of the present invention is to provide a seat belt device that has a simple configuration and suppresses the damage caused to the chest by a shoulder belt.

The present invention solves the above-mentioned problems by the following solving means.
The invention according to claim 1 provides a lap belt portion at least partially disposed across the vehicle width direction along the front of the occupant's waist, and at least a portion disposed diagonally along the front of the occupant's chest. a tongue having a webbing having a shoulder belt portion, and a slit portion through which an intermediate portion of the webbing is inserted, the tongue being provided between the lap belt portion and the shoulder belt portion and connected to the vehicle body when worn. The folded portion of the webbing in the tongue rotates in a direction in which the lower end moves forward relative to the upper end when viewed from the side of the vehicle in response to a vehicle collision or a sign of a collision. a pretensioner that applies tension to the webbing in response to a sign of the pretensioner, the folded part performs the rotation when the tension of the webbing temporarily decreases after the pretensioner operates, and the folded part The seat belt device is characterized in that it has a rotation regulating portion that regulates the rotation in the event of a non-collision and allows the rotation according to the tension of the webbing when the pretensioner is activated.
According to this, by rotating the folded part of the webbing in a direction in which the lower end moves forward relative to the upper end in the event of a vehicle collision, the direction in which the shoulder belt part is pulled out from the tongue is swung upward, and the shoulder belt part is pulled out from the tongue. The contact point with the shoulder belt portion can be displaced upward, and the behavior of the shoulder belt portion scooping up the occupant's ribs from below can be suppressed, and damage to the chest can be suppressed.
In addition, the above-mentioned effects can be obtained with a simple configuration that is completed inside the tongue.
In addition, by rotating the folded part when the tension of the webbing temporarily decreases and the webbing tends to loosen, the tension of the webbing does not impede the rotation of the folded part, ensuring reliable operation. , reliability can be increased.
Further, by allowing the folded portion to rotate only in the event of a collision, it is possible to prevent the usability of the seat belt device from being affected during normal use.

In the invention according to claim 2, the tongue changes from a free state in which the webbing can pass between the lap belt section side and the shoulder belt section side in response to a vehicle collision or a sign of a collision. The seat belt device according to claim 1, characterized in that the seat belt device is a locking tongue that transitions to a locked state in which the passage of the webbing is prohibited.
According to this, by placing the locking tongue in a locked state in response to a collision or a sign of a collision, it is possible to prevent the tension in the shoulder belt portion from increasing excessively and increasing the risk of harm to the ribs and the like.
Further, it is possible to suppress changes in the length of the shoulder belt portion before and after the collision, and to appropriately control the contact state between the shoulder belt portion and the occupant's upper body.

The invention according to claim 3 provides that the locking tongue has a locking member that is relatively displaced with respect to the main body when transitioning from the free state to the locked state, and that the folded portion is provided on the locking member. The seat belt device according to claim 2 is characterized in that the seat belt device is a seat belt device according to claim 2.
According to this, the above-mentioned effects can be reliably obtained with a simple configuration.

As described above, according to the present invention, it is possible to provide a seatbelt device with a simple configuration that suppresses injury to the chest caused by a shoulder belt.

1 is a perspective view schematically showing the configuration of a first embodiment of a seat belt device to which the present invention is applied. FIG. 2 is a schematic cross-sectional view of a locking tongue in the seat belt device of the first embodiment, showing a free state. FIG. 3 is a schematic cross-sectional view of a locking tongue in the seat belt device of the first embodiment, showing a locked state. FIG. 3 is a schematic view taken along the line IV-IV in FIG. 2; FIG. 4 is a schematic view taken along the line VV in FIG. 3; FIG. 2 is a block diagram schematically showing the configuration of a control system in the seat belt device of the first embodiment. It is a figure showing an example of transition of webbing tension at the time of a collision in the seat belt device of a 1st embodiment. FIG. 2 is a perspective view schematically showing a state after the locking tongue transitions to a locked state in the seat belt device of the first embodiment. FIG. 2 is a block diagram schematically showing the configuration of a control system in a second embodiment of a seat belt device to which the present invention is applied.

<First embodiment>
Hereinafter, a first embodiment of a seat belt device to which the present invention is applied will be described.
The seat belt device of the first embodiment is, for example, a three-point seat belt provided in a front seat of a vehicle such as a passenger car where an occupant is seated facing forward.

FIG. 1 is a perspective view schematically showing the configuration of a seat belt device according to a first embodiment.
The seat 10 on which the occupant P sits has a cushion 11 and a seat back 12.
The cushion 11 is provided at the lower part of the seat 10 and has a seat surface on which the buttocks and thighs of the occupant P are placed.
The seat back 12 is a portion that is provided to protrude upward from near the rear end of the seat portion and holds the back, shoulders, etc. of the occupant P.

A B-pillar 20 is provided on one side of the seat 10 in the vehicle width direction.
The B-pillar 20 is a columnar vehicle body structural member that extends in the vertical direction along the rear edge of a door opening through which the occupant P gets in and out.
The seat belt device 100 includes a webbing 110, a retractor 120, a lap pretensioner 130, a shoulder anchor 140, a locking tongue 150, a buckle 160, and the like.

The webbing 110 is a flexible belt-shaped member made of, for example, a knitted fabric of polyester fibers.
The webbing 110 has a lap belt portion 111 and a shoulder belt portion 112, with a locking tongue 150 through which the intermediate portion is inserted and folded back as a boundary.
The lap belt portion 111 is arranged to extend in the vehicle width direction, mainly along the front of the waist of the occupant P.
The shoulder belt portion 112 is arranged mainly along the front of the chest of the occupant P.
The shoulder belt portion 112 is arranged obliquely so that the B-pillar 20 side in the vehicle width direction is higher.

The retractor 120 is connected to the end of the webbing 110 on the shoulder belt 112 side, and is attached to the lower part of the B-pillar 20.
The retractor 120 has a function of winding up and storing the excess portion of the webbing 110.
Webbing 110 is adapted to be pulled upward from retractor 120.
The retractor 120 is provided with a shoulder pretensioner 121 (see FIG. 6) that pulls the shoulder belt portion 112 in response to a command from the seat belt control unit 210 using an actuator using, for example, a gunpowder-type gas generator. There is.

The lap pretensioner 130 is provided near the lower end of the B-pillar 20 of the vehicle body, and is connected to the outer end in the vehicle width direction of the lap belt portion 111 of the webbing 110.
The lap pretensioner 130 has a function of pulling the lap belt portion 111 in response to a command from the seat belt control unit 210 using, for example, an actuator using a gunpowder type gas generator.

The shoulder anchor 140 is provided near the upper end of the B-pillar 20 of the vehicle body, and is a portion where the shoulder belt portion 112 of the webbing 110 pulled upward from the retractor 120 is folded back diagonally downward toward the locking tongue 150 side.
The shoulder anchor 140 is rotatable with respect to the B-pillar 20 around an axis substantially along the vehicle width direction, and does not prevent the webbing 110 from passing between the retractor 130 side and the locking tongue 150 side. It looks like this.

The locking tongue 150 is a member that is detachably attached to the buckle 160 with the webbing 110 inserted therethrough.
In the webbing 110, a region closer to the pretensioner 130 than the locking tongue 150 functions as a lap belt section 111, and a region closer to the shoulder anchor 140 than the locking tongue 150 functions as a shoulder belt section 112.

The locking tongue 150 is configured so as not to obstruct the passage of the webbing 110 during normal use of the vehicle (non-collision), and when the tension of the webbing 110 increases due to a vehicle collision or the like, the locking tongue 150 The movement between the lap belt section 111 side and the shoulder belt section 112 side is restricted (locked).

Next, the configuration of the locking tongue 150 will be explained.
2 and 3 are schematic cross-sectional views of the locking tongue in the seat belt device of the first embodiment, showing a free state and a locked state, respectively.
FIG. 4 is a schematic view taken along the line IV-IV in FIG. 2.
FIG. 5 is a schematic view taken along the line VV in FIG. 3.
The locking tongue 150 includes a main body 151, a space 152, a lap belt slit 153, a shoulder belt slit 154, a locking member 155, a tongue plate 156, and the like.

The main body portion 151 is a portion into which the webbing 110 is inserted in a folded state between the lap belt portion 111 side and the shoulder belt portion 112 side.
The main body portion 151 is configured by combining, for example, a metal material, a hard resin material, etc. so as to have sufficient strength against the maximum tension that acts on the webbing 110 when a collision occurs, for example. (In Figures 2 and 3, the illustration is simplified.)

The space portion 152 is a hollow portion formed inside the main body portion 151, and accommodates a portion of the webbing 110, the lock member 155, and the like.
A sliding surface portion 152a and a lock recess portion 152b are formed on the inner surface of the space portion 152.
The sliding surface portion 152a is formed in a concave curved shape, contacts the sliding surface portion 155a of the locking member 155, and slides on the sliding surface portion 155a when the locking member 155 is operated.
The sliding surface portion 152a is formed on the inner surface of the region between the lap belt slit 153 and the shoulder belt slit 154 in the main body portion 151.
The lock recess 152 is a portion that cooperates with the lock member 155 to clamp and lock the webbing 110 when a predetermined tension or more is applied to the webbing 110 and the lock member 155 moves.
The lock recess 152b is formed on the inner surface of the space 152 in an area adjacent to the sliding surface 152a with the shoulder belt slit 154 in between.

The lap belt slit 153 and the shoulder belt slit 154 are openings that are formed to penetrate from the surface of the main body portion 151 to the inside of the space portion 152, and through which the webbing 110 is inserted.
The lap belt slit 153 and the shoulder belt slit 154 are formed as elongated slits having a longitudinal direction along the width direction of the webbing 110 (direction perpendicular to the paper plane in FIGS. 2 and 3).
The lap belt slit 153 allows the end of the lap belt portion 111 to be introduced into the space 152 .
The shoulder belt slit 154 allows the end of the shoulder belt portion 112 to be introduced into the space 152 .

The lock member 155 is disposed inside the space 152 and is movable to move from a free (released) position where the webbing 110 is allowed to pass to a locked position where the webbing 110 is restrained as the tension of the webbing 110 increases. It is a member.
The locking member 155 includes a sliding surface portion 155a, a webbing contact portion 155b, a webbing restraining portion 155c, and the like.
The sliding surface portion 155a is a convex curved portion that slidably contacts the sliding surface portion 152a on the inner surface 152 of the main body portion 151.
The webbing contact portion 155b is a convex portion (folded portion) that is provided on one end side (lower side in FIGS. 2 and 3) of the sliding surface portion 155a and comes into contact with a folded portion of the webbing 110.
As shown in FIG. 4, the webbing contact portion 155b is arranged to be inclined rearward with respect to the upper end thereof, as shown in FIG. 4 when viewed from the side during normal use of the vehicle.
When the locking tongue 150 is in the locked state, the webbing restraint part 155c works with the lock recess 152b to clamp and restrain the webbing 110, and the webbing 110 is held between the lap belt part 111 side and the shoulder belt part 112 side. This locks the locking tongue 150 so that it does not move past the locking tongue 150.
The webbing restraining portion 155c is provided on the end side of the sliding surface portion 155a opposite to the webbing contact portion 155b side (upper side in FIGS. 2 and 3).

The webbing 110 is folded back from the lap belt section 111 side to the shoulder belt section 112 side at the webbing contact section 155b.
When the locking tongue 150 is in a free state, the webbing 110 can freely pass through the locking tongue 150 by sliding along the surface of the webbing contact portion 155b (toward the lap belt portion 111 side or the shoulder belt portion 112 side). (passable).

When the tension acting on the webbing 110 increases during a vehicle collision, the locking tongue 150 transitions from the free state shown in FIGS. 2 and 4 to the locked state shown in FIGS. 3 and 5.
The locking member 155 is pulled upward in FIGS. 2 and 3 by the tension of the webbing 110, and the sliding surface portions 152a and 155a move while sliding against each other.
At the end of the movement range of the locking member 155, the webbing restraining portion 155c of the locking member 155 restrains the webbing 110 between it and the lock recess 152b formed in the space 152.

As shown in FIGS. 4 and 5, when the locking member 155 transitions from the free state to the locked state, the lower end of the webbing contact portion 155b moves forward relative to the upper end when viewed from the side of the vehicle. and rotates so as to rise.
The locus of movement of the locking member 155 from the free state position to the locked state position when viewed from the vehicle width direction is curved in an arc shape with a convex front side.
As a result, the direction in which the shoulder belt portion 112 is pulled out from the locking tongue 150 is shifted upward in the event of a collision compared to the normal direction.
Note that the locking member 155 regulates relative displacement with respect to the main body 151 during normal use of the vehicle (non-collision), and the regulation is released in response to an increase in the tension of the webbing 110 due to the operation of a pretensioner, for example. It can be configured to include a rotation regulating portion (not shown).
As the rotation regulating section, for example, a pin and an engagement hole into which the pin is inserted are provided on one side and the other of the main body section 151 and the locking member 155, respectively, so that the pin breaks as the tension of the webbing 110 increases. It is possible to configure a structure in which the restrictions are lifted by

The tongue plate 156 is a member that protrudes from the lower end of the locking tongue 150 when in use and engages with the engagement mechanism of the buckle 160.
The tongue plate 156 is made of a metal material such as a steel plate and has a flat plate shape.
The upper part of the tongue plate 156 is embedded and fixed in the lower part of the main body part 151 by insert molding or the like.
The buckle 160 is attached to a location inside the cushion 11 of the seat 10 in the vehicle width direction and close to the rear end of the vehicle body.
The buckle 160 has an engagement mechanism that engages with the tongue plate 157 of the locking tongue 150 when it is inserted, a release mechanism that releases the engagement mechanism, and the like.
A release button 161 for releasing the release mechanism is provided on the inner surface of the buckle 160 in the vehicle width direction.

The seat belt device 100 has a control system described below.
FIG. 6 is a block diagram schematically showing the configuration of a control system in the seat belt device of the first embodiment.
The control system 200 includes a seat belt control unit 210, a seating sensor 220, a seat belt wearing sensor 230, an acceleration sensor 240, an environment recognition unit 250, and the like.

The seat belt control unit 210 detects a collision or its precursor, and gives commands to each actuator (pretensioner) provided in the seat belt device 100.
The seating sensor 220 is a load sensor provided on the cushion 11 of the seat 10 and detects whether the occupant P is seated on the seat 10.
The seatbelt wearing sensor 230 is provided on the buckle 160 and detects a state in which the locking tongue 150 is connected to the buckle 160 (seatbelt wearing state).

The acceleration sensor 240 is provided, for example, at the front end of the vehicle body, and detects acceleration acting on the vehicle body in the front-rear direction or the like.
Acceleration sensor 240 is used as a sensor for detecting a vehicle collision.

The environment recognition unit 250 uses various sensors and communication such as vehicle-to-vehicle communication and road-to-vehicle communication to determine information about the shape of the road around the vehicle, other vehicles, pedestrians, buildings, terrain, obstacles such as trees, etc. It is used to recognize information, etc.
A stereo camera device 251, a millimeter wave radar device 252, a laser scanner device 253, a communication device 254, and the like are connected to the environment recognition unit 250.

The stereo camera device 251 includes a pair of cameras arranged with their imaging range facing the front of the vehicle and spaced apart in the vehicle width direction, and an image processing unit that performs known stereo image processing on images captured by each camera.
The millimeter wave radar device 252 detects the relative position, relative speed, etc. of an obstacle present in front of the vehicle, etc., with respect to the vehicle, using radio waves of, for example, 30 to 300 GHz.
The laser scanner device 253 is a 3D LIDAR that detects the shape and position of obstacles around the vehicle by emitting pulsed laser light and measuring scattered light.
The communication device 254 acquires information regarding obstacles that are difficult to detect by the above-mentioned sensors (for example, other vehicles appearing from a place blocked by a building, etc.) through vehicle-to-vehicle communication and road-to-vehicle communication.
The environment recognition unit 250 has a function of detecting a state where the possibility of a collision occurring is extremely high (a precursor to a collision) prior to an actual collision of the vehicle.
The seatbelt control unit 210 operates the shoulder pretensioner 121 and the lap pretensioner 130 in response to a sign of a collision.

FIG. 7 is a diagram showing an example of the transition of webbing tension during a collision in the seat belt device of the first embodiment.
In FIG. 7, the horizontal axis shows time and the vertical axis shows tension. Further, in FIG. 7, the tension in the lap belt portion is shown by a solid line, and the tension in the shoulder belt portion is shown by a broken line.
First, at time T1, when the environment recognition unit 250 determines that a frontal collision with another vehicle or the like is inevitable (pre-crash state), the shoulder pretensioner 121 and the lap pretensioner 130 are activated to reduce the slack in the webbing 110. The tension of the lap belt section 111 and the shoulder belt section 112 increases temporarily, and then decreases slightly.

Time T2 during which the tension of the webbing 110 (for example, the greater of the tension of the lap belt section 111 and the tension of the shoulder belt section 112) increases due to the operation of the shoulder pretensioner 121 and the lap pretensioner 130 and becomes equal to or higher than the threshold value Th1. At this point, the locking member 155 of the locking tongue 150 starts rotating. In conjunction with this, the lower end portion of the webbing contact portion 155b starts rotating in the direction of moving forward toward the front of the vehicle relative to the front end portion.
As described above, the tension of the webbing 110 decreases once after each pretensioner operates, and the webbing 110 tends to loosen; however, at this time, the tension of the webbing 110 does not hinder the rotation of the locking member 155. Rotation of the locking member 155 is promoted.

At time T3, the vehicle actually collides with an obstacle, longitudinal acceleration acts on the vehicle body, and the occupant P starts moving forward relative to the seat 10.
As a result, the tension in both the lap belt portion 111 and the shoulder belt portion 112 starts to increase, but at this time the tension in the lap belt portion 111 is greater than that in the shoulder belt portion 112.

Thereafter, at time T4, when the tension in the webbing 110 (for example, the greater of the tension in the lap belt section 111 and the tension in the shoulder belt section 112) becomes greater than the threshold value Th2, the locking tongue 150 enters the locked state. Become.
At the same time, the rotation of the webbing contact portion 155b also ends.
After that, the forward motion of the occupant's P's upper body increases, and the tension in the shoulder belt portion 112 further increases.

FIG. 8 is a perspective view schematically showing a state after the locking tongue transitions to the locked state (the folded portion of the webbing rotates) in the seat belt device of the first embodiment.
The direction in which the shoulder belt part 112 is pulled out from the locking tongue 150 is changed by rotating the webbing contact part 155b of the locking member 155, which is the folded part of the webbing 110, in the direction in which the lower end moves forward relative to the upper end. Swings upward.
As a result, the portion where the shoulder belt portion 112 contacts the chest of the occupant P is displaced upward.

According to the first embodiment described above, the following effects can be obtained.
(1) At the time of a vehicle collision, the shoulder belt portion 112 is pulled out from the locking tongue 150 by rotating the webbing contact portion 155b, which is the folded portion of the webbing 110, in a direction in which the lower end moves forward relative to the upper end. By swinging the direction upward, it is possible to displace the part of the occupant's P's chest which contacts the shoulder belt portion 112 upward.
At this time, although the change in the upward swinging angle of the shoulder belt section 112 in the direction in which it is pulled out from the locking tongue 150 is not large, the behavior of the shoulder belt section 112 scooping up the ribs R of the occupant P from below is similar to that of the shoulder belt section 112. This occurs when the shoulder belt portion 112 and the rib portion R come into contact with each other at a small angle, so the shoulder belt portion 112 and the rib portion R should make contact so that the angle θ (see Fig. 8) that they intersect is even slightly large. This has the effect of suppressing the behavior of scooping up the rib portion R from below.
Thereby, harm to the chest can be suppressed.
Moreover, the above-mentioned effects can be obtained by a simple structure that is completed inside the locking tongue 150.
(2) By locking the locking tongue 150 in response to a collision or a sign of a collision, it is possible to prevent the tension in the shoulder belt portion 112 from increasing excessively and increasing the risk of harm to ribs and the like.
Further, it is possible to suppress changes in the length of the shoulder belt portion 112 before and after the collision, and to appropriately control the contact state between the shoulder belt portion 112 and the upper body of the occupant P.
(3) By integrally forming the webbing contact portion 155b as a part of the locking member 155, the above-mentioned effects can be reliably obtained with a simple configuration.
(4) The locking member 155 having the webbing contact portion 155b rotates when the tension of the webbing 110 temporarily decreases after the shoulder pretensioner 121 and the lap pretensioner 130 operate, thereby increasing the tension of the webbing 110. The locking member 155 is rotated when the webbing tends to loosen due to a temporary decrease in the tension of the webbing 110, and the tension of the webbing 110 does not inhibit the rotation of the locking member 155, ensuring reliable operation. , reliability can be increased.
(5) A rotation restriction portion is provided that restricts rotation of the lock member 155 in the event of no collision and allows rotation according to the tension of the webbing 110 when the shoulder pretensioner 121 and the lap pretensioner 130 are activated. Therefore, it is possible to prevent the usability of the seat belt device from being affected during normal use.

<Second embodiment>
Next, a second embodiment of a seat belt device to which the present invention is applied will be described.
In the following description, parts similar to those in the first embodiment described above are given the same reference numerals, and the description thereof will be omitted, and differences will be mainly described.
FIG. 9 is a block diagram schematically showing the configuration of a control system in the seat belt device of the second embodiment.
The second embodiment has a locking tongue that operates in response to a command from a seatbelt control unit 210, instead of a passive locking tongue 150 that changes to the locked state depending on the tension of the webbing 110, as in the first embodiment. It includes an active locking tongue 150 that changes from a free state to a locked state by a tongue drive actuator 170.
As the locking tongue drive actuator 170, for example, various actuators such as an actuator using a gunpowder type gas generator or an electric actuator can be used.

Seat belt control unit 210 provides commands to locking tongue drive actuator 170 in response to detection of a collision or a precursor thereof.
As a result, the locking tongue 150 transitions from the free state to the locked state, but at this time, the webbing contact portion 155b (folded portion) of the locking member 155 rotates in a direction in which the lower end portion moves forward relative to the upper end portion. .
According to the second embodiment described above, in addition to the same effects as those of the first embodiment described above, locking of the locking tongue 150 and rotation of the folded portion of the webbing 110 are performed by the locking tongue drive actuator 170. Therefore, the degree of freedom in setting the actuation timing and the reliability of the actuation can be increased.

(Modified example)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the technical scope of the present invention.
(1) The configurations of the vehicle and the seat belt device are not limited to the above-described embodiments, and can be modified as appropriate.
For example, the shape, structure, function, arrangement, number, etc. of each part constituting the seat belt can be changed as appropriate.
(2) The configuration of the mechanism for rotating the folded portion in each embodiment is an example, and can be changed as appropriate.
For example, the internal structure of the tongue is just one example and can be changed as appropriate.
For example, in each embodiment, the locking member (movable member) of the locking tongue is configured to rotate as a whole and the folded part is rotated. The folded portion may be rotated relative to the tongue body by deforming or breaking the member provided with the tongue.
(3) In each embodiment, a locking tongue is used as the tongue, but the present invention can also be applied to a seat belt device having a tongue without a locking mechanism.

10 Seat 11 Cushion 12 Seat back 20 B-pillar 100 Seat belt device 110 Webbing 111 Lap belt portion 112 Shoulder belt portion 120 Retractor 121 Shoulder retractor 130 Lap pretensioner 140 Shoulder anchor 150 Locking tongue 151 Main body portion 152 Space portion 152a Sliding surface part 152b Lock recess 153 Lap belt slit 154 Shoulder belt slit 155 Lock member 155a Sliding surface portion 155b Webbing contact portion 155c Webbing restraint portion 156 Tongue plate 160 Buckle 161 Release button 170 Locking tongue drive actuator 200 Control system 210 Seat belt control unit 220 Seating sensor 230 Seat belt wearing sensor 240 Acceleration sensor 250 Environment recognition unit 251 Stereo camera device 252 Millimeter wave radar device 253 Laser scanner device 254 Communication device

Claims (3)

Webbing having a lap belt portion, at least a portion of which is disposed across the vehicle width direction along the front of the occupant's waist, and a shoulder belt portion, at least a portion of which is disposed obliquely along the front of the occupant's chest. and,
a tongue having a slit portion through which an intermediate portion of the webbing is inserted, provided between the lap belt portion and the shoulder belt portion, and connected to the vehicle body when worn;
The folded portion of the webbing in the tongue rotates in a direction in which a lower end portion moves forward relative to an upper end portion when viewed from the side of the vehicle in response to a vehicle collision or a sign of a collision;
a pretensioner that applies tension to the webbing in response to a vehicle collision or a sign of a collision;
The folded portion performs the rotation when the tension of the webbing temporarily decreases after the pretensioner is activated;
The folded portion may include a rotation restriction portion that restricts the rotation when there is no collision and allows the rotation according to the tension of the webbing when the pretensioner is activated.
A seat belt device featuring: The tongue changes from a free state in which the webbing can pass between the lap belt section side and the shoulder belt section side to a state in which the passage of the webbing is prohibited in response to a vehicle collision or a sign of a collision. The seat belt device according to claim 1, wherein the seat belt device is a locking tongue that transitions to a locked state. The locking tongue has a locking member that is displaced relative to the main body when transitioning from the free state to the locked state,
The seat belt device according to claim 2, wherein the folded portion is provided on the lock member .

Images