WO2018101019A1

WO2018101019A1 - Seat belt device and vehicle seat using same

Info

Publication number: WO2018101019A1
Application number: PCT/JP2017/040826
Authority: WO
Inventors: 徹也松下
Original assignee: オートリブディベロップメントエービー; 徹也松下
Priority date: 2016-12-01
Filing date: 2017-11-14
Publication date: 2018-06-07
Also published as: JPWO2018101019A1; JP6768829B2

Abstract

[Problem] To provide a novel seat belt device and a novel seat belt guide mechanism which provide a good balance between comfort and the ability to restrain an occupant, and a vehicle seat using the seat belt device and the seat belt guide mechanism. [Solution] This seat belt device is to be installed in a vehicle seat including a seat cushion and a seat back and is provided with: a seat belt for restraining an occupant seated on the vehicle seat; a retractor for rewinding the seat belt at an inner or lower section of the vehicle seat; and a guide mechanism which is disposed in an upper section of the seat back and which includes a guide fulcrum that supports, above the seat back, the seat belt fed from the retractor and extending in one-side direction of the occupant. Furthermore, the guide mechanism includes an adjustment mechanism part that enables, with respect to the longitudinal direction in a side view of the seat back, the angle of inclination of the seat belt extending from the guide fulcrum in the shoulder direction of the occupant to be variable in a predetermined range of the front-to-back thickness direction of the seat back when the seat back is viewed from the side of the occupant in the seat back.

Description

Seat belt device and vehicle seat using the same

The present invention relates to a vehicle seat, and more particularly, to a seat belt device provided with a retractor on a seat.

The seat belt plays an extremely important role in ensuring the safety of passengers in the vehicle. The seat belt device is provided with a belt retracting mechanism (retractor) so as to automatically retract the seat belt.

By the way, the environment in which the seat belt device is installed varies depending on the vehicle or the structure of the seat. In a seat belt device for a driver seat or a passenger seat, a retractor is often disposed below the B pillar, and a mechanism for guiding the belt is often disposed above the B pillar. In such a state, the belt extends from the retractor through a route such as a belt guide mechanism, an occupant front surface, and a buckle.

In recent years, the development of automatic driving of automobiles has been progressing rapidly, and when automatic driving is realized, it is expected that the arrangement and orientation of seats will be more free than ever. In such a case, the seat belt retractor cannot be installed on the vehicle (pillar) and is installed on the seat. If so, the seat belt height adjusting mechanism that has been provided in the pillar until now cannot be used. The same applies to a rear seat or a front seat of a vehicle having no B pillar.

If the retractor cannot be installed in the vehicle, the seat belt device including the retractor will be installed in the seat itself. When such a structure is employed, the retractor is disposed below the seat or in the seat back, and a guide portion is provided on a shoulder portion (upper portion of the seat back). The belt extends in the chest and waist direction of the occupant through the guide portion. At this time, a force that the seat belt presses the periphery of the occupant's chest against the seat back acts, so that a feeling of pressure around the occupant's chest increases and comfort may be reduced.

In particular, for small passengers (adults), the seatbelt extends at an angle so that the seatbelt is in direct contact with the chest with little contact with the shoulder. , Discomfort is relatively strong. In the case of a child who sits directly on a seat without using a child seat, it is preferable to sufficiently relieve pressure on the chest.

On the other hand, if the tension of the seat belt is lowered in order to reduce the pressure on the occupant's chest by the seat belt, the occupant's rapid restraint at the time of sudden deceleration such as a collision may be hindered.

The inventor of the present application has tested various pre-crash devices with respect to vehicle seats and has shown that the seat belt device of the present invention is most effective.

The present invention has been made in view of the situation as described above, and provides a novel seat belt device, a seat belt guide mechanism, and a vehicle seat using the same, in which the restraint and comfort of an occupant are well balanced. The purpose is to provide.

Another object of the present invention is to provide a seat belt device, a seat belt guide mechanism, and a vehicle seat using the seat belt device that can exhibit appropriate restraint performance according to the physique of the occupant.

In order to solve the above-described problems, the present invention provides a seat belt device provided in a vehicle seat having a seat cushion and a seat back, the seat belt restraining an occupant seated on the vehicle seat; A retractor that winds up the seat belt inside or below the vehicle seat; and disposed above the seat back and extended from the retractor and extending in one direction of the occupant above the seat back. A guide mechanism including a guide fulcrum to be supported. When the seat back is viewed from the side of an occupant seated on the seat back, the guide mechanism has a shoulder direction of the occupant from the guide fulcrum within a predetermined range in the front-rear thickness direction of the seat back. And an adjustment mechanism that makes the angle of inclination with respect to the longitudinal direction variable in a side view of the seat back of the seat belt.
Here, the seat lower portion includes a portion below the seat cushion and the seat back. The upper part of the seat back includes the vicinity of the upper end of the seat back and the part above the upper end.

According to the present invention as described above, the direction in which the seat belt extends can be adjusted according to the situation of the vehicle and the occupant's physique, avoiding the chest compression of the occupant, and improving the occupant restraint performance in a pre-crash state Is possible.

Preferably, the adjustment mechanism unit operates at the time of a vehicle collision or immediately before it. This is not only in the case where a collision actually occurs and the airbag is deployed, but also in the pre-crash state where the automatic brake and seatbelt pretensioner are activated, at the same time as these pre-crash safety devices. This means that the adjusting mechanism of the invention is operated.

The adjusting mechanism section preferably guides the inclination angle of the seat belt in a direction approaching a direction orthogonal to the longitudinal direction in a side view of the seat back at the time of or just before the collision of the vehicle. With such a configuration, at the time of a vehicle collision or just before that, the seat belt looks like pressing the shoulder of the occupant downward, avoiding unnecessary compression on the chest by the seat belt, It becomes possible to improve a passenger | crew's restraint performance. In particular, in the case of a vehicle having a function capable of predicting a collision, such as mounting an automatic brake device, the adjustment mechanism is operated before the collision so that reliable preparation can be made before the actual collision occurs. There are benefits.

The adjustment mechanism includes a base fixed to the seat back, and an arm swingable in a vehicle front-rear direction around a rotation shaft provided on the base, and the base of the arm It is possible to adopt a structure in which the guide fulcrum is moved downward by setting the guide fulcrum in the vicinity of the tip on the opposite side and swinging the arm forward or backward. In this case, since the guide fulcrum moves not only in the vertical direction but also in the front-rear direction, there is an advantage that the angle adjustment range in which the seat belt extends can be increased. Note that a simple configuration in which the guide fulcrum is lowered can be employed as the adjustment mechanism.

The adjustment mechanism can be configured to move the guide fulcrum downward by swinging the arm forward when a child sits on the seat. For example, regardless of the behavior of the automobile such as a collision accident, the angle at which the seat belt extends can be optimized by previously tilting the arm forward when the child gets on. It is possible to obtain a certain effect by tilting the arm backward, but by tilting the arm forward, not only can the pressure on the child's chest be relieved more effectively, but also a seat belt is placed on the neck. The possibility can be reduced.

After the occupant seated on the seat wears the seat belt, the arm can be operated to further include a determination device configured to determine the physique of the occupant. The determination device can rotate concentrically with the load sensor provided in the vicinity of the coupling portion between the guide mechanism and the seat back, the sensor for measuring the retract amount of the seat belt of the retractor, or the rotation shaft of the arm And a potentiometer that detects an angle from when the seat belt is brought into contact with the drum to a position perpendicular to the longitudinal direction in a side view of the seat back. It can be set as the structure which determines a passenger | crew's physique based on the detected value of the said load, the said drawer amount, or the said angle.

When the occupant's physique is determined, the pull-out load of the seat belt between the guide mechanism and the retractor can be changed accordingly. For example, when it is determined that the occupant's physique is greater than a certain reference, the load adjustment mechanism operates so that the pull-out load (load) of the seat belt increases.

The load adjusting mechanism includes a pair of shafts having parallel rotation axes, can change a route of the seat belt passing between the pair of shafts, and can adjust a pull-out load of the seat belt.
In the following description, the terms “upper” and “lower” refer to the relative positional relationship with the ceiling direction as the “up” direction and the floor direction as the “down” direction as seen from the center of the vehicle in the vertical direction. Show. Further, “front” and “rear” indicate the front and rear of the occupant normally seated on the seat, and “side” indicates the lateral direction of the occupant.

FIG. 1 is a side view (partially see through) showing a schematic structure of a vehicle seat according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating the structure of the seat belt guide mechanism according to the embodiment of the present invention. FIG. 3 is an explanatory view showing the operation of the seat belt device according to the embodiment of the present invention. (A) is a normal use state, (B) is a state during an emergency operation, and (C) is a use state when a child is seated. FIG. 4 is an explanatory diagram illustrating a physique determination operation in the seat belt device according to the embodiment of the present invention. (A) is a state before operation, (B) is a determination operation state when a passenger with a relatively small physique is seated, and (C) is a determination operation state when an occupant with a relatively large physique is seated. FIG. 5 is an explanatory diagram showing the operation of the guide mechanism when the occupant is a small adult in the seat belt device according to the embodiment of the present invention. (A) shows a normal state, and (B) shows a state at the time of occupant restraint. FIG. 6 is an explanatory diagram illustrating the operation of the guide mechanism when the occupant is an average adult in the seat belt device according to the embodiment of the present invention. (A) shows a normal state, and (B) shows a state at the time of occupant restraint. FIG. 7 is an explanatory view showing the operation of the guide mechanism when the occupant is a large adult in the seat belt device according to the embodiment of the present invention. (A) shows a normal state, and (B) shows a state at the time of occupant restraint. FIG. 8 is an explanatory diagram illustrating the operation of the guide mechanism when the occupant is a child in the seat belt device according to the embodiment of the present invention. (A) shows a normal state, and (B) shows a state at the time of occupant restraint. FIG. 9 is an explanatory view showing another example of the physique determination mechanism in the seat belt device according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a side view (partially see through) showing a schematic structure of a vehicle seat according to an embodiment of the present invention. FIG. 2 is a schematic view showing the structure of the seat belt guide mechanism (20) according to the embodiment of the present invention.

A vehicle seat according to an embodiment of the present invention includes a seat cushion 10 on which an occupant P is seated, a seat back 12 that supports the back of the occupant P, and a headrest 16 provided at the upper end of the seat back 12. The seat belt device used for such a vehicle seat includes: a seat belt 14 that restrains an occupant P seated on the seat cushion 10; a retractor 18 that winds up the seat belt 14 at a lower portion of the seat; And a guide mechanism 20 that supports the seat belt 14 at the guide fulcrum 26.

When the seat back 12 is viewed from the side of the occupant P, the guide mechanism 20 seats on the seat belt 14 that extends from the guide fulcrum 26 toward the occupant P's shoulder within a predetermined range in the front-rear thickness direction of the seat back 12. An adjustment mechanism (22, 24) is provided that makes the inclination angle with respect to the longitudinal direction variable in a side view of the back 12. By preventing the guide mechanism 20 from greatly protruding back and forth beyond the thickness of the seat back 12, other occupants P and other passengers collide with the guide mechanism 20 due to the impact of the collision and are obstructed. The possibility is suppressed. However, “within a predetermined range in the thickness direction of the seat back” does not necessarily mean that the thickness of the seat back does not protrude strictly. Protruding to the extent that it does not interfere and does not excessively interfere with the occupant is allowed.

The vehicle seat according to the present embodiment can be applied, for example, to a seat of a rear seat of a passenger car or a wagon car, or to a seat of a driver seat or a passenger seat of a vehicle not provided with a B pillar. In FIG. 1, reference numeral 40 denotes a load adjusting mechanism for adjusting a load (load) generated on the belt 14 by frictional resistance, which will be described in detail later.

As shown in FIG. 2A, the adjustment mechanism portions (22, 24) of the guide mechanism 20 include a base portion 22 fixed to the seat back 12 and a rotating shaft 22 a provided on the base portion 22. An arm 24 that can swing in the front-rear direction of the occupant P is included. A shaft-shaped guide fulcrum 26 is provided in the vicinity of the tip of the arm 24 on the side opposite to the base portion 22. The swing operation of the arm 24 can be performed by a motor (not shown), and the operating range in the front-rear direction can be set to 180 ° (front 90 °, rear 90 °), for example.

Here, the base portion 22 can be installed inside the seat back 12, but the guide fulcrum 26 must be arranged outside the seat back 12.

As shown in FIG. 2B, the guide fulcrum 26 can be moved downward by swinging the arm 24 backward. In this case, since the guide fulcrum 26 moves not only in the vertical direction but also in the front-rear direction, the angle adjustment range in which the seat belt 14 extends is increased. In the case of FIG. (B), it is assumed that the passenger P is an adult.

As shown in FIG. 2 (C), the adjustment mechanism (22, 24) is configured to move the guide fulcrum 26 downward by swinging the arm 24 forward when the child sits on the seat. be able to. For example, regardless of the behavior of the automobile such as a collision accident, the angle at which the seat belt 14 extends can be optimized by previously tilting the arm 24 forward when the child rides. It is possible to obtain a certain effect by tilting the arm 24 backward. However, by tilting the arm 24 forward, not only can the pressure on the child's chest be more effectively reduced, but also the seat belt 14 on the neck. It is possible to reduce the possibility that the

FIG. 3 is an explanatory view showing the operation of the seat belt device according to the embodiment of the present invention, and corresponds to (A), (B), and (C) of FIG. That is, (A) shows a normal use state in which an adult P is seated, (B) shows a state in an emergency operation when the adult P is seated, and (C) shows a use state when a child is seated. For convenience of explanation, illustration of constituent members of the guide mechanism other than the guide fulcrum 26 is omitted.

2 (A) and 3 (A), the seatbell guide fulcrum 26 is at the highest position. From this state, for example, when a collision prediction signal is output, as shown in FIGS. 2 (B) and 3 (B), the arm 24 is tilted backward to move the guide fulcrum 26 to a lower position, and The angle (inclination angle) at which the belt 14 extends is made closer to the horizontal (in the direction orthogonal to the longitudinal direction in a side view of the seat back). As a result, the seat belt 14 looks like pressing the shoulder of the occupant P downward, it is possible to avoid unnecessary pressure on the chest by the seat belt 14 and to improve the restraining performance of the occupant P. .

On the other hand, as shown in FIG. 2 (C) and FIG. 3 (C), when the passenger P is a child or an adult with a small physique, it overlaps with the previous explanation, but it is related to the behavior of the car such as a collision accident. Instead, when sitting, the arm 24 is tilted forward in advance to make the angle (tilt angle) at which the seat belt 14 extends closer to the horizontal.

As described above, the adjusting mechanism 20 operates at the time of or just before the collision of the vehicle. That is, the adjustment mechanism 20 is operated not only in the case where a collision actually occurs and the airbag (not shown) is deployed, but also in a state before the collision in which the automatic brake or the seat belt pretensioner is activated. be able to. In particular, in the case of a vehicle having a function capable of predicting a collision, such as mounting an automatic brake device, by operating the adjustment mechanism unit 20 before the collision, it can be surely prepared until the actual collision occurs. There are benefits.

FIG. 4 is an explanatory view showing a physique determination operation in the seat belt device according to the embodiment of the present invention. (A) is a state before operation, (B) is a determination operation state when a passenger with a relatively small physique is seated, and (C) is a determination operation state when an occupant with a relatively large physique is seated.

As shown in FIGS. 4A to 4C, in this embodiment, the physique of the occupant P seated on the seat can be determined by operating the arm 24. Specifically, from the initial state before the operation as shown in (A), the arm 24 is slowly tilted backward, and the seat belt 14 comes into contact with the drum 44 arranged to be rotatable concentrically with the rotating shaft 22a of the arm 24. The potentiometer detects the angles (θ1, θ2) from when the arm 24 reaches the horizontal H (in the direction perpendicular to the longitudinal direction in the side view of the seat back). As shown to (B), in the case of the passenger | crew P with a comparatively small physique, rotation angle (theta) 1 of the drum 44 becomes small. On the other hand, as shown in (C), in the case of the occupant P having a relatively large physique, the rotation angle θ2 of the drum 44 increases.

When the physique determination of the occupant P is completed, the arm 24 returns to the initial position. Then, when the possibility of a collision increases, the pull-out load of the seat belt 14 between the guide fulcrum 26 and the retractor 18 is adjusted. For example, when it is determined that the physique of the occupant P is larger than a certain reference, the pull-out load (load) of the seat belt 14 is increased by the load adjustment mechanism unit 40.

The load adjustment mechanism unit 40 includes a pair of

shafts

40L and 40R whose rotation axes are parallel to each other, changes the path of the seat belt 14 passing between the

shafts

40L and 40R, and connects the seat belt 14 and the

shafts

40L and 40R. The pull-out load of the seat belt 14 is adjusted by changing the frictional force. As described above, the load adjustment mechanism unit 40 can serve as a load limiter. Note that the load adjustment mechanism 40 is fixed to the seat frame 50.

Next, the operation of this embodiment will be described in more detail with reference to FIGS. 5 to 8 in addition to FIGS. 5 to 8 are explanatory views showing the operation of the guide mechanism 20 based on the result of the physique determination. 5 to 8, (A) shows the normal state, and (B) shows the state when the occupant is restrained.

First, when the occupant P is seated, the physique of the occupant is determined by the method described above. Here, when the occupant P is a small adult (AF05), as shown in FIG. 5B, at the time when the possibility of a collision is increased, the arm 24 is rotated rearward by the motor at the same time or immediately thereafter. The

twin shafts

40L and 40R are rotated by an angle (for example, 45 °) according to the physique, so that the seat belt 14 is in a semi-fixed state. At this time, since the range in which the seat belt 14 is wound around the

twin shafts

40L and 40R is short, the friction on the seat belt 14 is relatively small.

When the occupant P is an average adult (AM50), as shown in FIG. 6 (B), when the possibility of a collision is increased, the arm 24 is rotated rearward by a motor at the same time or immediately thereafter. The

twin shafts

40L and 40R are rotated by an angle (for example, 135 °) according to the physique, so that the seat belt 14 is semi-fixed. At this time, the range in which the seat belt 14 is wound around the

twin shafts

40L and 40R is longer than that in the case of FIG. 5B, so the friction on the seat belt 14 is increased accordingly.

In the case where the passenger P is a large adult (AM95), as shown in FIG. 7B, at the time when the possibility of collision increases, the twin is rotated at the same time or immediately after the arm 24 is rotated backward by the motor. The

shafts

40L and 40R are rotated by an angle (for example, 180 °) according to the physique, so that the seat belt 14 is in a semi-fixed state. At this time, the range in which the seat belt 14 is wound around the

twin shafts

40L and 40R is longer than that in the case of FIGS. 5B and 6B, and therefore the friction on the seat belt 14 is increased accordingly.

When the passenger P is a child (Q6 / 10) smaller than a certain standard, the arm 24 is tilted forward and fixed in advance as shown in FIG. In the load adjustment mechanism 40, even when the possibility of a vehicle collision increases, the

shafts

40L and 40R are not rotated or slightly rotated to the seat belt 14 as shown in FIG. 8B. Minimize the applied load (friction).

Thereafter, when it is determined that collision avoidance is impossible, the pretensioner (powder) of the retractor 18 is activated, tension is applied to the seat belt 14, and the occupant P is firmly restrained against the seat. The occupant P is prevented from moving into a deployment range of a bag (not shown) to prepare for a collision. As described above, since the load applied to the seat belt 14 is adjusted using the

twin shafts

40L and 40R, the seat belt 14 is applied to an occupant with a large physique after the first pre-tension is applied to the seat belt 14. Is difficult to loosen and the binding force increases. On the other hand, in the case of an occupant with a small physique, the seat belt 14 is relatively easy to loosen, and excessive compression can be prevented.

When the collision is avoided, the

twin shafts

40L and 40R are rotated to loosen the seat belt 14 and the arm 24 is rotated forward, so that FIG. 5 (A), FIG. 6 (A), FIG. ) And the

twin shafts

40L and 40R are further rotated to return to the initial positions.

The timing for rotating the

twin shafts

40L and 40R according to the physique of the occupant P should be immediately after the physique of the occupant is detected, as described above, at a stage where the possibility of collision has increased, or immediately after the collision. You can also. Here, when the twin shafts 40 </ b> L and 40 </ b> R are operated at the stage where the possibility of a collision is increased or immediately after the collision, the operation can be interlocked with the operation of the arm 24.

FIG. 9 is an explanatory view showing another example of the physique determination mechanism in the seat belt device according to the present invention. In this example, a load sensor 402 that detects a thrust load with respect to the bearing 400 of the rotating shaft 22 a is provided inside the base portion 22. Then, the physique of the occupant is determined based on the output change of the load sensor 402 when the arm 24 is tilted backward (see FIG. 4). Moreover, the sensor of another form can be employ | adopted as a sensor used for a passenger | crew's physique determination mechanism. For example, a mechanism that detects a strain generated between specific members due to the operation of the arm 24 is conceivable.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and can be modified within the scope of the technical idea shown in the claims.

Assuming the case where the characteristic guide mechanism 20 of the present invention does not operate normally (for example, when a necessary signal is not received), a pretensioner based on pyrotechnics, which has been conventionally used, for example, By installing at the lower part of the seat back 12, a minimum tension can be applied to the seat belt. Further, the pyrotechnic energy for operating the pretensioner can be used to rotate the

twin shafts

40L and 40R, thereby imparting an appropriate frictional resistance to the seat belt 14 and applying a desired tension to the seat belt 14.

Claims

In a seat belt device equipped in a vehicle seat having a seat cushion and a seat back,
A seat belt for restraining an occupant seated on the vehicle seat;
A retractor that winds up the seat belt inside or under the vehicle seat;
A guide mechanism including a guide fulcrum disposed above the seat back and supporting the seat belt extended from the retractor and extending in one direction of the occupant above the seat back;
The guide mechanism extends from the guide fulcrum in the shoulder direction of the occupant within a predetermined range in the front-rear thickness direction of the seat back when the seat back is viewed from the side of the occupant seated on the seat back. A seat belt device comprising: an adjustment mechanism that varies an inclination angle with respect to a longitudinal direction in a side view of the seat back of the seat belt.
2. The seat belt device according to claim 1, wherein the adjustment mechanism section operates at the time of a vehicle collision or immediately before the collision.
The adjustment mechanism unit guides the inclination angle of the seat belt in a direction approaching an orthogonal direction of a longitudinal direction in a side view of the seat back at or just before a vehicle collision. The seat belt device according to the description.
The seat belt device according to claim 2 or 3, wherein the adjustment mechanism section operates to lower the guide fulcrum at or just before a vehicle collision.
The seat belt device according to any one of claims 1 to 4, wherein the adjustment mechanism section is capable of adjusting a movable range according to a physique of an occupant.
The adjustment mechanism includes a base fixed to the seat back and an arm swingable in the vehicle front-rear direction around a rotation shaft provided on the base.
The guide fulcrum is provided in the vicinity of the tip of the arm on the side opposite to the base portion,
The seat belt device according to any one of claims 1 to 5, wherein the guide fulcrum is moved downward by swinging the arm forward or backward.
The seat belt device according to claim 6, wherein the adjustment mechanism unit moves the guide fulcrum downward by swinging the arm forward when a child sits on the seat.
8. The apparatus according to claim 6, further comprising a determination device configured to determine a physique of the occupant by operating the arm after a seated occupant wears the seat belt. 9. Seat belt device.
The determination device can rotate concentrically with the load sensor provided in the vicinity of the coupling portion between the guide mechanism and the seat back, the sensor for measuring the retract amount of the seat belt of the retractor, or the rotation shaft of the arm And a potentiometer that detects an angle from when the seat belt is brought into contact with the drum to a position perpendicular to the longitudinal direction in a side view of the seat back.
9. The seat belt device according to claim 8, wherein the physique of the occupant is determined based on the detected value of the load, the amount of withdrawal, or the angle.
10. The seat according to claim 9, further comprising a load adjustment mechanism that changes a pull-out load of the seat belt between the guide mechanism and the retractor according to a determination result by the determination device. Belt device.
When the occupant's physique determined by the determination device is large, the load adjustment mechanism portion increases the pull-out load (load) of the seat belt, and when the occupant's physique determined is small, the load adjustment mechanism. The seat belt device according to claim 10, wherein the portion operates so as to reduce a pull-out load (load) of the seat belt.
The load adjustment mechanism unit includes a pair of shafts whose rotation axes are parallel,
The seat belt device according to claim 10 or 11, wherein a route of the seat belt passing between the pair of shafts is changed to adjust a pull-out load of the seat belt.
A vehicle seat provided with the seat belt device according to any one of claims 1 to 11.
In a seat belt guide mechanism that is disposed on an upper part of a seat back of a vehicle seat and includes a guide fulcrum that supports the seat belt,
An adjustment mechanism including a base fixed to the seat back and an arm capable of swinging in a vehicle longitudinal direction around a rotation shaft provided in the base;
The guide fulcrum is provided in the vicinity of the tip of the arm on the side opposite to the base portion,
By swinging the arm forward or backward, when the seat back is viewed from the side of an occupant, the guide fulcrum is moved downward within a predetermined range in the front-rear thickness direction of the seat bag, A seat belt guide mechanism, wherein an inclination angle of the seat belt extending in a shoulder direction of the occupant from the guide fulcrum with respect to a longitudinal direction is made close to a horizontal in a side view of the seat back.
15. The seat belt guide mechanism according to claim 14, wherein the adjusting mechanism section operates at the time of a vehicle collision or immediately before the collision.
The adjustment mechanism unit guides the inclination angle of the seat belt in a direction approaching a direction orthogonal to the longitudinal direction of the side view of the seat back at the time of or just before the collision of the vehicle. Seat belt guide mechanism.
17. The seat belt guide mechanism according to claim 15 or 16, wherein the adjustment mechanism unit operates to lower the guide fulcrum at or just before a vehicle collision.
The seat belt guide mechanism according to any one of claims 14 to 17, wherein the adjustment mechanism section is capable of adjusting a movable range according to a physique of an occupant.
The adjustment mechanism includes a base fixed to the seat back and an arm swingable in the vehicle front-rear direction around a rotation shaft provided on the base.
The guide fulcrum is provided in the vicinity of the tip of the arm on the side opposite to the base portion,
The seat belt guide mechanism according to any one of claims 14 to 18, wherein the guide fulcrum is moved downward by swinging the arm forward or backward.
The seat belt guide mechanism according to claim 19, wherein the adjustment mechanism unit moves the guide fulcrum downward by swinging the arm forward when a child sits on the seat.
21. The seat according to claim 19 or 20, further comprising a determination device configured to be able to determine the physique of the occupant by operating the arm after the seated occupant wears the seat belt. Belt guide mechanism.
The determination device can rotate concentrically with the load sensor provided in the vicinity of the coupling portion between the guide mechanism and the seat back, the sensor for measuring the retract amount of the seat belt of the retractor, or the rotation shaft of the arm And a potentiometer that detects an angle from when the seat belt is brought into contact with the drum to a position perpendicular to the longitudinal direction in a side view of the seat back.
The seat belt guide mechanism according to claim 21, wherein the physique of the occupant is determined based on the detected value of the load, the amount of withdrawal, or the angle.
23. The seat according to claim 22, further comprising a load adjustment mechanism that changes a pull-out load of the seat belt between the guide mechanism and the retractor according to a determination result by the determination device. Belt guide mechanism.
When the occupant's physique determined by the determination device is large, the load adjustment mechanism portion increases the pull-out load (load) of the seat belt, and when the occupant's physique determined is small, the load adjustment mechanism. The seat belt guide mechanism according to claim 23, wherein the portion operates so as to reduce a pull-out load (load) of the seat belt.
The load adjustment mechanism unit includes a pair of shafts whose rotation axes are parallel,
The seat belt guide mechanism according to claim 23 or 24, wherein a route of the seat belt passing between the pair of shafts is changed to adjust a pull-out load of the seat belt.