WO2023199762A1

WO2023199762A1 - Seat belt device

Info

Publication number: WO2023199762A1
Application number: PCT/JP2023/013577
Authority: WO
Inventors: 豊中島; 修司川▲崎▼; 大輔井口; 匠伊藤; 崇也室屋; 翔村上; 良太石垣; 剛珠片岡
Original assignee: オートリブディベロップメントエービー; 豊中島; 修司川▲崎▼; 大輔井口; 匠伊藤; 崇也室屋; 翔村上; 良太石垣; 剛珠片岡
Priority date: 2022-04-15
Filing date: 2023-03-31
Publication date: 2023-10-19

Abstract

Provided is a seat belt device capable of improving the restraint performance of an occupant using a seat belt while reducing pressure on the abdominal region of the occupant during an emergency.　The seat belt device 1 comprises a seat belt 10 that has a tongue 22 inserted therethrough, and a retraction device 30 that causes, as objects to be retracted, a buckle 28 to which the tongue 22 can be connected and/or a lap anchor 24 which is linked to an end of the seat belt 10, to move along a retraction path 50 during an emergency. The retraction path 50 includes a first path section 51 along which the objects to be retracted are first turned and moved forward and downward during an emergency, and a second path section 52 along which the objects to be retracted are then turned and moved rearward and downward.

Description

seat belt device

The present invention relates to a seat belt device.

Generally, in a three-point seat belt device, the seat belt for restraining an occupant includes a shoulder belt extending from an upper guide loop or an upper anchor to a tongue, and a lap belt extending from the tongue to a lower anchor. , the tongue is configured to be insertable into a buckle fixed to the vehicle body. By inserting and fastening the tongue into the buckle, the seat belt device forms a three-point restraint between the upper anchor, the buckle (tang), and the lower anchor. In this state, the shoulder belt stretches diagonally in front of the occupant's chest from the top of one side of the occupant to the bottom of the other, and the lap belt stretches from one side of the occupant to the other side of the occupant's waist. A bridge is placed in front of you. Such a three-point seat belt device prevents the occupant from being thrown forward in an emergency such as a vehicle collision.

There are also known three-point seatbelt devices that are equipped with a pretensioner that retracts the seatbelt when the vehicle suddenly decelerates or collides. For example, in Patent Document 1, a pretensioner wire is connected to a buckle, and the wire is pulled diagonally downward and rearward when the vehicle suddenly decelerates or collides. This allows the seatbelt to be retracted via the buckle, restraining the occupant who attempts to move forward due to inertia when the vehicle suddenly decelerates or collides.

Additionally, as a three-point seatbelt device, technology related to a split buckle (split buckle) is also known, which enables forward movement of the buckle position by separating the seatbelt at the buckle during a collision. (See Patent Document 1). According to this document, by separating the lap belt and the shoulder belt, it is possible to reduce the belt tension acting on the chest without reducing the waist restraint force.

International Publication No. 2008/155942

By the way, if the occupant is excessively restrained by the seat belt, the burden on the ribs, the lower part of the ribs, the abdomen, etc. will increase. In order to reduce the load on the occupant, it is preferable that the seat belt be able to quickly restrain the skeleton of the human body (particularly the clavicle and ilium), which is difficult to deform.

In this respect, conventional seat belt devices had room for improvement. For example, as in Patent Document 1, if the buckle is momentarily pulled only in the direction of inclination of the wire, the lap belt will press the occupant's abdomen and will not easily hit the ilium. Further, as in Non-Patent Document 1, it is complicated to provide a mechanism that enables the separation of the lap belt and the shoulder belt, and furthermore, this configuration does not take into account the application of the lap belt to the ilium.

In particular, during a vehicle collision, a submarine phenomenon may occur in which the occupant's body slips under the lap belt. The submarine phenomenon is more likely to occur when the seat is reclined. When a submarine phenomenon occurs, the position of the lap belt rises relative to the occupant, which prevents the lap belt from performing its original function and may put pressure on the occupant's abdomen.

An object of the present invention is to provide a seatbelt device that can improve the ability of the seatbelt to restrain an occupant while reducing the burden on the occupant's abdomen in an emergency.

A seatbelt device according to one aspect of the present invention includes a seatbelt into which a tongue is inserted, and a buckle to which the tongue can be coupled, and/or a lap anchor coupled to an end of the seatbelt. , a retraction device that moves the retraction target along a retraction trajectory in an emergency, and the retraction trajectory includes a first trajectory segment that first pivots the retraction target forward and downward in the emergency, and then a first trajectory segment that moves the retraction target backward and forward. and a second trajectory segment for pivoting downward.

According to this aspect, the seat belt can be moved via the retraction target so as to follow the movement of the occupant's pelvis in an emergency. Specifically, in an emergency, the lap belt portion of the seat belt first pivots forward and downward of the occupant's abdomen, away from the occupant, and comes to rest on the ilium. The portion of the lap belt that covers the ilium then pivots rearward and downward, pressing against the ilium and thereby restraining the occupant. Therefore, in an emergency, it is possible to improve the performance of restraining the occupant by the seat belt while reducing the burden on the occupant's abdomen. In particular, the configuration of the retracting locus that changes the turning mode is effective against submarine phenomena in which the position of the seat belt tends to rise relative to the occupant.

FIG. 1 is a perspective view schematically showing a state in which a seat belt device according to an embodiment is mounted on a vehicle. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view schematically showing a state in which a seatbelt device according to an embodiment is mounted on a vehicle together with a passenger. FIG. 2 is a side view showing a retracting device of a seat belt device according to an embodiment. 4 is an operation diagram showing the locus of the buckle moved by the retracting device of FIG. 3, (a) shows an initial state (normal time) before the retracting device operates, and (b) shows the buckle moving when the retracting device operates. shows the buckle moving along the first trajectory segment, (c) shows the buckle moving along the second trajectory segment, and (d) shows the actuation of the retraction device completed. Shows the later state. It is an operation diagram showing the locus of the buckle moved by the retracting device according to a comparative example, (a) shows the initial state (normal time) before the retracting device operates, and (b) shows the operation of the retracting device completed. Shows the later state. FIG. 7 is a perspective view showing a retraction device according to another embodiment. FIG. 7 is an exploded perspective view of the retraction device of FIG. 6; 7 is a sectional view showing a part of a retracting device according to a first modification example in which the power transmission mechanism is different from that of the retracting device in FIG. 6. FIG. 7 is a sectional view showing a part of a retracting device according to a second modification example in which the power transmission mechanism is different from that of the retracting device in FIG. 6. FIG.

A seat belt device according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In this document, top and bottom, left and right, and front and rear are defined as follows. When an occupant is seated in a seat (vehicle seat) in a normal posture, the direction in which the occupant faces is referred to as the front, and the opposite direction is referred to as the rear, and the axis of coordinates is referred to as the longitudinal direction. Further, when an occupant is seated in a vehicle seat in a normal posture, the right side of the occupant is referred to as the right direction, and the left side of the occupant is referred to as the left direction, and the axis of coordinates is referred to as the left-right direction. Similarly, when an occupant is seated in a normal posture, the direction of the occupant's head is referred to as upward, the direction of the occupant's waist is referred to as downward, and the axis of coordinates is referred to as the up-down direction.

As shown in FIG. 1, the vehicle seat 100 includes a seat back 110 that supports the back of an occupant, a seat cushion 112 on which the occupant sits, and a headrest 114 that supports the occupant's head. The vehicle seat 100 may be a front seat (ie, a driver's seat or a passenger seat) or a rear seat. Inside the seat back 110 and the seat cushion 112, a seat frame and a sitting frame forming the frame of the seat are provided, respectively, and these are connected to each other via a reclining mechanism. In the seat cushion 112, for example, the surface of a seat pad made of a urethane foam material or the like that covers the surface and surroundings of the seating frame is covered with a seat cover made of leather, fabric, or the like.

The seat belt device 1 is provided in association with a vehicle seat 100, and has a seat belt 10 that is a webbing that restrains an occupant. Seat belt 10 has a shoulder belt 12 extending from an upper guide loop or upper anchor 20 to a tongue 22 and a lap belt 14 extending from tongue 22 to a lap anchor 24. The shoulder belt 12 is stretched diagonally in front of the occupant's chest from the upper part of the left and right sides of the occupant seated on the vehicle seat 100 to the lower part of the other left and right sides. The lap belt 14 is stretched from one side of the passenger to the other side in front of the waist of the passenger. The shoulder belt 12 and the lap belt 14 are formed into one continuous belt.

The upper anchor 20 is provided on the upper wall of the vehicle interior or on the upper part of the seat back 110. Although not shown, a retractor for retracting one end of the seat belt 10 may be provided below the upper anchor 20, and the retractor may be fixed to the vehicle body or the seat cushion 112.
The tongue 22 is inserted through the seat belt 10 and is configured to be connectable to the buckle 28. Specifically, the tongue 22 has a loop portion 26 through which the seat belt 10 is slidably inserted. By attaching the tongue 22 to the buckle 28 and fastening it, the seat belt 10 is folded back with the loop portion 26 as a boundary, and is divided into the shoulder belt 12 and the lap belt 14.
The lap anchor 24 is for fixing the other end of the seat belt 10 to a portion of the vehicle structure (for example, a vehicle frame, a seat frame, a seating frame, etc.). Therefore, when tongue 22 is coupled to buckle 28 , seat belt device 1 defines a three-point restraint between upper anchor 20 , tongue 22 (buckle 28 ), and lap anchor 24 .

Additionally, the seat belt device 1 includes a retraction device 30 that moves the lap anchor 24 and/or buckle 28 along a predetermined retraction trajectory in an emergency. The emergency situation refers to, for example, a vehicle collision, an impact event to the vehicle, a vehicle overturning, etc., but is not limited thereto.

All or most of the retraction device 30 is provided, for example, on the side of the seat cushion 112 or between the floor surface of the vehicle body and the seat cushion 112. If provided on the side of the seat cushion 112, all or most of the retraction device 30 may be provided within the seat cushion 112, attached to the inner surface of the seating frame, or alternatively, attached to the outer surface of the seating frame. As attached, all or most of the retraction device 30 may be provided outside the seat cushion 112.

The object to be retracted by the retracting device 30 may be both the lap anchor 24 and the buckle 28, or may be either one of them. In the following, an example in which the buckle 28 is the retracting target will be described.

FIG. 2 shows the position of the buckle 28 before and after the retraction device 30 is activated. In FIG. 2, the configuration related to the symbols indicated by the two-dot chain leader line indicates the position before the retracting device 30 is operated, and the configuration related to the symbol indicated by the solid leader line indicates the position after the retracting device 30 is operated. Actuation of the retraction device 30 finally moves the buckle 28 to the rearward and downward position. However, the buckle 28 is first pivoted forward and downward, and then pivoted backward and downward. Furthermore, the curvatures of these two turning movements are different.

As shown in FIG. 3, the buckle 28 has a main body portion 280 and a stay 282. The main body portion 280 is configured to be connectable with the tongue 22. For example, the main body portion 280 is formed with an insertion opening for inserting the tongue 22 and is provided with a release button for unlocking the tongue 22. The tongue 22 is fixed to the buckle 28 simply by the passenger inserting the tongue 22 into the insertion opening, and the tongue 22 is released from the lock of the buckle 28 only by the passenger pressing the release button.

The stay 282 extends from the main body portion 280 to the opposite side from the tongue 22. The stay 282 is made of, for example, a metal plate member, supports the main body portion 280, and is fixed to the retraction device 30. Specifically, one end side of the stay 282 supports the main body portion 280 fixedly or movably. For example, when the buckle 28 is configured as a so-called swing buckle, the main body portion 280 is configured to be rotatable in the front-back direction of the seat and tiltable in the width direction of the seat with respect to the stay 282.

The other end of the stay 282 is fixed to the retraction device 30. Specifically, the stay 282 has a first fixing part 291 and a second fixing part 292, the first fixing part 291 is connected to the drive arm 32 of the retracting device 30, and the second fixing part 292 is connected to the drive arm 32 of the retracting device 30. is connected to the driven arm 33 of the retraction device 30. Further, the stay 282 is connected to the drive arm 32 and the driven arm 33 at a first fixing portion 291 and a second fixing portion 292, respectively, so as to be relatively rotatable. For example, the first fixing part 291 and the second fixing part 292 are formed as pin holes, and are connected to the driving arm 32 and the driven arm 33 via a connecting pin.

On the other end side of the stay 282, the first fixing part 291 is located at the end of the stay 282, and the second fixing part 292 is located between the end and the main body part 280. Further, the first fixing part 291 and the second fixing part 292 are located on the central axis of the stay 282 and on the central axis of the main body part 280.

The retraction device 30 has a power source 31, a drive arm 32, and a driven arm 33. Further, the retracting device 30 includes a piston cylinder unit 35 and a wire member 36 as a power transmission mechanism 34 that transmits power from the power source 31 to the drive arm 32.

The structure of an existing pretensioner can be used for the power source 31, the piston cylinder unit 35, and the wire member 36. An example will be explained below.

The power source 31 is composed of a gas generator, for example, a micro gas generator (MGG). The power source 31 is electrically connected to, for example, a vehicle-side ECU, receives a signal detecting an emergency situation from the vehicle-side ECU, operates, and generates gas.
The piston cylinder unit 35 includes a piston 37 (movable member) driven by gas pressure from the power source 31, and a cylinder 38 that slidably accommodates the piston 37.
Wire member 36 connects piston 37 and drive arm 32. In an emergency, the wire member 36 is drawn into the inner side of the cylinder 38 by driving the piston 37.

Specifically, in an emergency, when the power source 31 is activated, the generated gas causes the piston 37 to move toward the interior of the cylinder 38. As a result, the wire member 36 connected to the piston 37 is retracted, rotational power is input to the drive arm 32 connected to the wire member 36, and the drive arm 32 rotates in the direction of the arrow 39.

The drive arm 32 is connected to the first fixed portion 291 of the stay 282 and rotates about the first rotating shaft 41 upon input of rotational power generated by the operation of the power source 31. The drive arm 32 is made of, for example, a substantially fan-shaped plate, has a first rotating shaft 41 at the center, and has a connection point 32a connected to the first fixing part 291 at an end.

Furthermore, the drive arm 32 has an input section 43 at a position away from the first rotating shaft 41 to which the rotational power generated by the operation of the power source 31 is input. Here, the input section 43 is configured as an anchor to which the end of the wire member 36 is fixed. Further, the drive arm 32 has a plurality of (three in this case) guide portions 44 that guide the wire member 36. The guide portions 44 are arranged along the outer shape of the drive arm 32 and guide a portion of the wire member 36 located between the input portion 43 and the piston 37.

The driven arm 33 is connected to the second fixed portion 292 of the stay 282 and rotates about the second rotation shaft 42 following the rotation of the drive arm 32. The driven arm 33 is made of, for example, an arcuate plate, has a second rotating shaft 42 at one end, and a connecting point 33a connected to the second fixing part 292 at the other end.

The drive arm 32 and the driven arm 33 are rotatably supported by the fixed plate 45 at the positions of the first rotation shaft 41 and the second rotation shaft 42, respectively. Moreover, as described above, the drive arm 32 and the driven arm 33 are connected to the stay 282 so as to be relatively rotatable at the positions of the first fixing part 291 and the second fixing part 292, respectively. Therefore, in the retracting device 30, a four-bar link mechanism is configured in which the first fixed part 291, the second fixed part 292, the first rotating shaft 41, and the second rotating shaft 42 are paired. In other words, in the stay 282, the portion between the first fixed part 291 and the second fixed part 292 functions as a link, and the portion between the first fixed part 291 and the second fixed part 292 functions as a link, and the part between the drive arm 32, the driven arm 33, and the first rotation shaft 41 of the fixed plate 45 and the portion between the second rotating shaft 42 and the second rotating shaft 42 constitute a four-bar link mechanism.

The operation of the retracting device 30 will be described with reference to FIG. 4. In FIG. 4 , reference numeral 50 indicates a movement trajectory of the main body portion 280 of the buckle 28 , that is, a retraction trajectory by the retraction device 30 . Note that the wire member 36 is omitted in FIG. 4.

In an emergency, when the power source 31 is activated, the wire member 36 is retracted by driving the piston 37, thereby inputting rotational power to the drive arm 32. Then, the drive arm 32 rotates about the first rotating shaft 41 and moves the stay 282 of the buckle 28. Then, the driven arm 33 connected to the stay 282 rotates about the second rotating shaft 42 . In this way, in an emergency, the retracting device 30 inputs rotational power generated by the operation of the power source 31 to the drive arm 32 and rotates the drive arm 32 and the driven arm 33, thereby pulling the main body 280 of the buckle 28. It is moved along the pull-in locus 50.

The retraction trajectory 50 includes a first trajectory segment 51 in which the buckle 28 is pivoted forward and downward in an emergency, and a second trajectory segment 52 in which the buckle 28 is then pivoted backward and downward. The retraction trajectory 50 also includes a third trajectory segment 53 after which the buckle 28 is pivoted rearward and slightly upward. Note that the third trajectory section 53 can be omitted.

Specifically, as shown in FIG. 4(b), in an emergency, the retraction device 30 first pivots the buckle 28 forward and downward along the first trajectory section 51. Then, as shown in FIG. 4(c), the retraction device 30 pivots the buckle 28 backward and downward along the second trajectory segment 52. Thereafter, as shown in FIG. 4(d), the retraction device 30 pivots the buckle 28 backward and slightly upward along the third trajectory segment 53.

The curvature in the first trajectory segment 51 and the curvature in the second trajectory segment 52 are different. Here, the curvature of the former is smaller than the curvature of the latter. Further, the amount of downward movement of the buckle 28 in the first trajectory section 51 and the amount of downward movement of the buckle 28 in the second trajectory section 52 are different. Here, the former movement amount is larger than the latter movement amount.

With the above configuration, the retracting device 30 causes the buckle 28 and the seat belt 10 to act on the occupant as follows. In an emergency, the buckle 28 first pivots forward and downward, so the lap belt 14 pivots forward and downward of the occupant's abdomen away from the occupant, and comes to rest on the occupant's ilium. The buckle 28 then pivots rearward and downward, thereby pressing the occupant's ilium against the seat back 110 so that the lap belt 14 approaches the occupant. This restrains the occupant.

Therefore, in an emergency, an occupant attempting to move forward of the vehicle is restrained by the lap belt 14 that is stretched around the ilium, and the lap belt 14 is prevented from digging into the occupant's abdomen. As described above, according to the present embodiment, in an emergency, the performance of restraining the occupant by the seat belt 10 can be improved while reducing the burden on the occupant's abdomen. In particular, the configuration of the retracting trajectory 50 that changes the turning mode is effective against the submarine phenomenon in which the position of the seat belt 10 tends to rise relative to the occupant.

Furthermore, according to the present embodiment, in order to achieve the above-described retraction trajectory 50, the retraction device 30 is configured to have two arms (the drive arm 32 and the driven arm 33). Thereby, the curvature of the circular arc in the retraction locus 50 can be reduced while reducing the size of the retraction device 30. This point will be explained in detail with reference to FIG.

FIG. 5 shows a retraction device 300 according to a comparative example. This retracting device 300 is composed of one arm 90 and is not provided with the above-mentioned driven arm 33. In the retracting trajectory 500 by the retracting device 300, the curvature of the circular arc becomes large. For this reason, the trajectory becomes close to a straight line. Further, since the curvature of the circular arc is large, the length of the arm 90 becomes long. If the curvature of the circular arc is reduced in the retracting locus 500 by the retracting device 300, the retracting stroke will become smaller.

In contrast, in the retraction device 30 according to the present embodiment, a driven arm 33 is provided in addition to the drive arm 32, and the stay 282 of the buckle 28 functions as a link. Thereby, the curvature of the circular arc in the pull-in locus 50 can be reduced, and the locus can be prevented from becoming close to a straight line. Further, the length of the drive arm 32 can be shortened, and as a result, the overall size of the retracting device 30 can be reduced.

[Another embodiment]
Next, a retraction device 130 according to another embodiment will be described with reference to FIGS. 6 and 7. This retracting device 130 differs from the retracting device 30 described above mainly in the shape of the drive arm and the method of inputting rotational power to the drive arm. Of the retracting device 130, components that are common to the retracting device 30 are given the same or similar numerals as the components of the retracting device 30, and description thereof will be omitted.

The retracting device 130 inputs rotational power generated by the operation of the power source 131 to the drive arm 132 via the first rotating shaft 141. Specifically, the retraction device 130 inputs rotational power generated by the operation of the power source 131 from the first rotating shaft 141 to the drive arm 132 via the reduction gear train 200.

The reduction gear train 200 includes a sun gear 201 coaxially connected to the first rotating shaft 141 and a plurality of (four in this case) planetary gears that mesh with the sun gear 201 and are rotatably supported by the drive arm 132. 202, and an internal gear 203 that meshes with the plurality of planetary gears 202.

The first rotating shaft 141 has a connecting shaft portion 141a that is connected to the sun gear 201 so as to be able to transmit torque. The outer periphery of the connecting shaft portion 141a has, for example, an involute tooth profile, and is connected to the inner surface of the sun gear 201. Further, the first rotating shaft 141 has a wire engaging portion 141b connected to an end thereof so that a wire member 360 is wound thereon. In the retracting device 30 described above, one end of the wire member 36 was fixed to the input part 43 of the drive arm 32, but in the retracting device 130 of this embodiment, one end of the wire member 360 is connected to the wire of the first rotating shaft 141. It is engaged with the engaging portion 141b.

Further, the first rotating shaft 141 is rotatably supported by the first fixing plate 211 at a shaft portion 141c between the connecting shaft portion 141a and the wire engaging portion 141b, and is opposite to the wire engaging portion 141b. The side end 141d is rotatably supported by the second fixed plate 212.

Similarly to the drive arm 32, the drive arm 132 has a connection point 132a that is connected to the first fixed part 291 of the stay 282. The drive arm 132 is provided with a first rotation shaft 141, a sun gear 201, and a planet gear 202 on the opposite side of the connection point 132a. The first rotating shaft 141 passes through the drive arm 132 and is rotatably supported by the first fixed plate 211 and the second fixed plate 212. The sun gear 201 and the planet gear 202 are located on the first fixed plate 211 side of the drive arm 132.

Similar to the driven arm 33, the driven arm 133 has a connection point 133a connected to the second fixed part 292 of the stay 282. The driven arm 133 is provided with a second rotating shaft 142 on the opposite side of the connection point 133a. The second rotating shaft 142 is rotatably supported by the first fixed plate 211.

The internal gear 203 is provided on the third fixed plate 213. The third fixing plate 213 is located between the first fixing plate 211 and the second fixing plate 212 and is fixed thereto.

In the retracting device 130, when the power source 131 is activated in an emergency, the piston 37 is driven to move the wire member 360, thereby rotating the wire engaging portion 141b of the first rotating shaft 141. Then, rotational power is transmitted from the connecting shaft portion 141a of the first rotating shaft 141 to the sun gear 201, and the sun gear 201 rotates. As a result, the planetary gear 202 rotates about the first rotating shaft 141 while meshing with the internal gear 203. Then, the drive arm 132 that pivotally supports the planetary gear 202 rotates around the first rotating shaft 141, moves the stay 282 of the buckle 28, and thereby moves the driven arm 133 connected to the stay 282 to the second Rotate around the rotation axis 142 of.

In this way, the retraction device 130 inputs rotational power generated by the operation of the power source 131 to the drive arm 132 via the first rotating shaft 141 and the reduction gear train 200 in an emergency. Then, similarly to the retraction device 30, by rotating the drive arm 132 and the driven arm 133, the main body portion 280 of the buckle 28 is moved along the retraction locus 50.

Note that in the retracting device 130, the power transmission mechanism 134 that transmits power from the power source 131 to the drive arm 132 not only connects the piston cylinder unit 35 and the wire member 360, but also the first rotating shaft 141 and the reduction gear train 200. It can be said that it has.

Therefore, similarly to the embodiments described above, according to this embodiment, in an emergency, it is possible to improve the performance of restraining the occupant by the seat belt 10 while reducing the burden on the abdominal region of the occupant. An advantage over the above embodiments is the use of a planetary gear mechanism. The planetary gear mechanism allows deceleration to be performed, thereby making it possible to operate the retracting device 130 efficiently, and making it possible to further reduce the size of the retracting device 130.

The embodiments described above are intended to facilitate understanding of the present invention, and are not intended to be interpreted as limiting the present invention. The elements included in each embodiment, their arrangement, materials, conditions, shapes, sizes, etc. are not limited to those illustrated, and can be changed as appropriate.

For example, regarding the retracting device 130, as a mechanism for rotating the first rotating shaft 141, one end of the wire member 360 is wound around the end of the first rotating shaft 141, and the movement of the wire member 360 causes the first rotating shaft 141 to rotate. Although a mechanism for rotating is used, the present invention is not limited to this. For example, an existing pretensioner mechanism that is not a wire type can be applied. Two examples of this will be explained.

[First modification]
FIG. 8 shows an example in which the power transmission mechanism 134 that transmits power from the power source 131 to the drive arm 132 uses a ball 800 and a pinion 820 instead of the piston cylinder unit 35 and the wire member 360.

The balls 800 are movable members driven by gas pressure from the power source 131, which is a gas generator, and a plurality of balls 800 are housed in a tube 810. The pinion 820 is a rotating member that engages with the ball 800 and rotates when the ball 800 is driven. A first rotation shaft 141 is provided at the rotation center of the pinion 820, and the pinion 820 and the first rotation shaft 141 rotate together.

Therefore, in an emergency, when the power source 131 is activated, gas from the gas generator is supplied into the tube 810, and the ball 800 inside the tube 810 is moved. As a result, the pinion 820 rotates, and the first rotating shaft 141 rotates together with the rotation of the pinion 820. Thereafter, this rotational power is input to the drive arm 132 via the reduction gear train 200, as described above.

[Second modification example]
FIG. 9 shows an example in which the power transmission mechanism 134 that transmits power from the power source 131 to the drive arm 132 uses a rack 900 and a pinion 920 instead of the piston cylinder unit 35 and the wire member 360.

The rack 900 is a movable member driven by gas pressure from the power source 131, which is a gas generator. Rack 900 is housed within cylinder 910. The pinion 920 is a rotating member that engages with the rack 900 and rotates when the rack 900 is driven. A first rotation shaft 141 is provided at the rotation center of the pinion 920, and the pinion 920 and the first rotation shaft 141 rotate together.

Therefore, in an emergency, when the power source 131 is activated, gas from the gas generator is supplied into the cylinder 910, and the rack 900 is slid within the cylinder 910 to increase the amount of exposure to the outside of the cylinder 910. As a result, the pinion 920 rotates, and the first rotating shaft 141 rotates together with the rotation of the pinion 920. Thereafter, this rotational power is input to the drive arm 132 via the reduction gear train 200, as described above.

[Other embodiments]
Although the buckle 28 has been described as an example of the object to be retracted, the lap anchor 24 may be the object to be retracted instead of or in addition to the buckle 28. In this case, the lap anchor 24 has a main body connected to the end of the seat belt 10 and a stay extending from the main body and fixed, and this stay is similar to the stay 282 of the buckle 28. (i.e., a first fixing part 291 and a second fixing part 292 fixed to the driving arms 32, 132 and the driven arms 33, 133 of the retracting devices 30, 130). The main body of the lap anchor 24 may have an opening for holding an end of the seat belt 10.

DESCRIPTION OF SYMBOLS 1... Seat belt device, 10... Seat belt, 12... Shoulder belt, 14... Lap belt, 20... Upper anchor, 22... Tongue, 24... Lap anchor, 26... Loop portion, 28... Buckle, 30... Retraction device, 31 ...Power source, 32... Drive arm, 32a... Connection point, 33... Followed arm, 33a... Connection point, 34... Power transmission mechanism, 35... Piston cylinder unit, 36... Wire member, 37... Piston, 38... Cylinder, 39 ...Arrow, 41...First rotation axis, 42...Second rotation axis, 43...Input section, 44...Guide section, 45...Fixing plate, 50...Pull-in locus, 51...First locus division, 52...Second rotation axis 2 trajectory segment, 53... Third trajectory segment, 90... Arm, 100... Vehicle seat, 110... Seat back, 112... Seat cushion (seat portion), 114... Headrest, 130... Retraction device, 131... Power source, 132... Drive arm, 132a... Connection point, 133... Followed arm, 133a... Connection point, 134... Power transmission mechanism, 141... First rotating shaft, 141a... Connection shaft section, 141b... Wire engagement section, 141c... Shaft part, 141d... end, 142... second rotating shaft, 200... reduction gear train, 201... sun gear, 202... planetary gear, 203... internal gear, 211... first fixed plate, 212... second fixed plate, 213... Third fixing plate, 280... Main body, 282... Stay, 291... First fixing part, 292... Second fixing part, 300... Retracting device, 360... Wire member, 500... Retracting locus, 800... Ball , 810... tube, 820... pinion, 900... rack, 910... cylinder, 920... pinion

Claims

A seat belt with a tongue inserted through it,
As a retracting object, a buckle to which the tongue can be connected and/or a retracting device that moves a lap anchor connected to an end of the seat belt along a retracting trajectory in an emergency;
The retraction trajectory includes a first trajectory segment in which the retraction target is pivoted forward and downward in the event of an emergency, and a second trajectory segment in which the retraction target is then pivoted backward and downward. belt device.
Regarding the target of attraction,
The buckle includes a main body portion to which the tongue can be coupled, and a stay extending from the main body portion and fixed thereto,
The lap anchor includes a main body connected to an end of the seat belt, and a stay extending from and fixed to the main body,
The retraction device is
power source and
a drive arm that is connected to a first fixed part of the stay to be retracted and that rotates about a first rotation axis upon input of rotational power generated by the operation of the power source;
a driven arm that is connected to a second fixed part of the stay to be retracted and that rotates about a second rotation axis following rotation of the drive arm;
The retraction device inputs the rotational power to the drive arm in the event of an emergency and rotates the drive arm and the driven arm, thereby moving the main body portion to be retracted along the retraction locus. , The seat belt device according to claim 1.
The seat belt device according to claim 2, wherein the retraction device inputs the rotational power generated by the operation of the power source to the drive arm via the first rotation shaft.
The seat belt device according to claim 3, wherein the retraction device inputs the rotational power generated by the operation of the power source from the first rotating shaft to the drive arm via a reduction gear train.
The reduction gear train includes a sun gear coaxially connected to the first rotating shaft, a plurality of planetary gears meshing with the sun gear and rotatably supported by the drive arm, and the plurality of planetary gears. The seat belt device according to claim 4, further comprising an internal gear meshing with the seat belt device.
The power source is a gas generator,
The retraction device is
a movable member driven by gas pressure from the gas generator;
Any one of claims 3 to 5, further comprising a wire member that connects the movable member and the first rotating shaft and is moved by driving of the movable member to rotate the first rotating shaft. Seat belt device described in.
The power source is a gas generator,
The retraction device is
a movable member driven by gas pressure from the gas generator;
a rotating member that engages with the movable member and rotates when the movable member is driven;
The seat belt device according to any one of claims 3 to 5, wherein the first rotation shaft is provided at the rotation center of the rotation member, and the rotation member and the first rotation shaft rotate together.
3. The seat belt device according to claim 2, wherein the drive arm has an input section located away from the first rotation shaft, into which the rotational power generated by the operation of the power source is input.
The power source is a gas generator,
The retraction device is
a movable member driven by gas pressure from the gas generator;
The seat belt device according to claim 8, further comprising a wire member that connects the movable member and the input section and is drawn in by driving of the movable member to rotate the drive arm.
Any one of claims 2 to 5, wherein a four-bar linkage mechanism is configured in which the first fixed part, the second fixed part, the first rotating shaft, and the second rotating shaft are paired. Seat belt device described in.
The seat belt device according to any one of claims 2 to 5, wherein the first fixing part and the second fixing part are located on the central axis of the main body part to be retracted.
The stay has the first fixing part at an end, and the second fixing part between the end and the main body part, according to any one of claims 2 to 5. Seat belt device.
The amount of downward movement of the drawing object in the first trajectory segment is larger than the amount of downward movement of the drawing object in the second trajectory segment, according to any one of claims 1 to 5. seat belt device.
The seat belt device according to any one of claims 1 to 5, wherein a curvature in the first trajectory segment is smaller than a curvature in the second trajectory segment.