JP7255509B2 - vehicle seat belt device - Google Patents

Description

The present invention relates to a vehicle seatbelt device.

Patent Literature 1 listed below discloses an invention relating to a vehicle seat belt device. In this vehicle seat belt device, a tongue plate attached to a three-point seat belt that restrains an occupant seated on a vehicle seat is engaged with a buckle, and the buckle is connected to a piston via a retracting member. . The piston is actuated at the time of a vehicle collision, and the actuation moves the buckle toward the lower side of the seat. Therefore, the lap belt that restrains the lumbar region of the occupant is pulled in the occupant restraining direction through the buckle and the tongue plate, so that the occupant slips under the lap belt toward the front of the seat when the vehicle suddenly decelerates, which is called the submarine phenomenon. can be suppressed.

JP 2019-172049 A

By the way, at the time of a vehicle collision in which an occupant seated in a vehicle seat moves to the front side of the seat (hereinafter referred to as a "forward movement collision"), the occupant's submarine in various postures including a comfortable state in which the seat back is reclined. In order to effectively suppress this phenomenon, it is desirable to pull the lap belt toward the lower side of the seat at a portion corresponding to the lower part of the pelvis of the occupant at the time of a forward movement collision. This makes it difficult for the occupant's lower back (pelvis) to tilt forward and come off the lap belt. However, when the occupant is in a comfortable state, the pelvis moves toward the front side of the seat and tilts backward compared to when the occupant is normally seated. In this state, as in the configuration disclosed in Patent Document 1, if the buckle is pulled toward the lower side of the seat, the upper side of the pelvis is pulled toward the lower side of the seat, so the pelvis tilts further backwards and the submarine phenomenon is likely to occur. may become. Therefore, the prior art described above has room for improvement in this respect.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vehicle seatbelt device capable of effectively suppressing the occurrence of the submarine phenomenon in the event of a forward-moving collision involving a passenger in a comfortable state.

A vehicle seat belt device according to the first aspect of the invention includes a webbing having a lap belt for restraining the waist or thighs of an occupant seated on a vehicle seat having a seat back and a seat cushion, and the seat cushion. and a buckle engaged with a tongue plate attached to the boundary between the lap belt and other parts of the webbing; a retracted position of the buckle; a lift-up mechanism unit that moves to either one of a raised position, a pretensioner mechanism unit that is connected to the buckle and operates to pull the buckle toward the seat front side and the seat lower side of the seat cushion, and the When the reclining angle of the seatback is detected and danger is predicted when the reclining angle is greater than or equal to a predetermined angle, the lift-up mechanism moves the buckle to the raised position, and then a vehicle collision is detected. and a control unit for operating the pretensioner mechanism when the pretensioner mechanism is activated.

According to the first aspect of the invention, the vehicle seatbelt device includes a webbing, a buckle, a lift-up mechanism, a pretensioner mechanism, and a controller. The webbing has a lap belt that restrains the waist or thighs of an occupant seated on a vehicle seat having a seat back and a seat cushion. The buckle is engaged with a tongue plate positioned on the side of the seat cushion and attached to the boundary between the webbing lap belt and other parts. The buckle can be moved to either a retracted position or a raised position by a lift-up mechanism. Further, the buckle is connected to a pretensioner mechanism, and the buckle is pulled toward the seat front side and the seat lower side on the seat cushion side by the operation of the pretensioner mechanism. The control unit causes the lift-up mechanism to move the buckle to the raised position when danger is predicted in a state in which the reclining angle of the seatback is greater than or equal to a predetermined angle. After that, the controller activates the pretensioner mechanism when a vehicle collision is detected. That is, by moving the buckle to the raised position by the lift-up mechanism, the tension of the lap belt is weakened. By activating the pretensioner mechanism in this state, the buckle and lap belt can be moved farther toward the front side of the seat than when the tension of the webbing is not weakened. Therefore, even in a comfortable state in which the pelvis moves toward the front side of the seat and tilts backward compared to the normal seated state, the lap belt can be easily moved to a position corresponding to the lower pelvis of the occupant. It can be retracted to the lower side of the seat at this position. As a result, the pelvis of the occupant can be tilted forward to make it difficult for the lap belt of the webbing to come off from the pelvis, thereby suppressing the occurrence of the submarine phenomenon.

The vehicle seat belt device according to the first aspect of the present invention has the excellent effect of effectively suppressing the occurrence of the submarine phenomenon in the event of a forward movement collision, including for a passenger in a comfortable state.

BRIEF DESCRIPTION OF THE DRAWINGS It is a side view which shows the vehicle seatbelt apparatus which concerns on one Embodiment. FIG. 2 is a side view showing an extended state (raised position) of the essential parts of the vehicle seat belt device according to the embodiment; It is a side view which shows the contracted state (storage position) of the principal part in the vehicle seatbelt apparatus which concerns on one Embodiment. 1 is a block diagram showing the hardware configuration of a vehicle seatbelt device according to one embodiment; FIG. 1 is a block diagram showing a functional configuration of a vehicle seatbelt device according to one embodiment; FIG. It is a flow chart which shows a flow of operation of a seat belt device for vehicles concerning one embodiment. It is a side view which shows the seatbelt apparatus for vehicles which concerns on a comparative example.

An embodiment of a vehicle seat belt device according to the present invention will be described below with reference to FIGS. 1 to 6. FIG. An arrow FR shown appropriately in these figures indicates the front side of the seat, an arrow UP indicates the upper side of the seat, and an arrow OUT indicates the outside in the width direction of the seat. Further, in this embodiment, the seat front-rear direction, the seat width direction, and the seat up-down direction substantially coincide with the vehicle front-rear direction, the vehicle width direction, and the vehicle up-down direction, respectively.

(overall structure)
As shown in FIG. 1, a vehicle seat belt device 10 according to this embodiment includes a webbing 12, a buckle 14, a tongue plate 16, an anchor bracket 18, a lift-up mechanism 20, and a pretensioner mechanism. 22 and a control unit 24 . The vehicle seat belt device 10 is provided on a vehicle seat 32, and the vehicle seat 32 has a seat cushion 32A and a seat back 32B. The seat cushion 32A, on which the occupant P sits, is attached to a vehicle floor (not shown) via a seat rail 34. As shown in FIG. The seat cushion 32A incorporates a seat cushion frame (not shown) that is a skeleton member.

A seatback frame (both not shown) is provided on the seat rear side of the seat cushion frame via a reclining mechanism. The seatback frame is a frame member of the seatback 32B that supports the waist L of the occupant P seated on the seat cushion 32A from the rear side of the seat, and is formed in a substantially rectangular frame shape when viewed from the front of the vehicle. The reclining mechanism is provided with a reclining angle detection sensor 38 (see FIG. 4) that acquires the reclining angle, that is, the inclination angle of the seat back 32B with respect to a virtual reference plane composed of the seat width direction and the vertical direction. ing.

(webbing)
The webbing 12 is a non-stretchable belt-like member for restraining the occupant P seated on the vehicle seat 32 . The webbing 12 has a lap belt 12A that restrains the lumbar region L side of the thighs F of the occupant P and a shoulder belt 12B that restrains the chest region C of the occupant P when worn by the occupant P. . A tongue plate 16 is attached to the webbing 12 . In the webbing 12 when worn by a passenger, the shoulder belt 12B and the lap belt 12A are separated by the tongue plate 16 as a boundary.

The anchor bracket 18 is provided behind the seat and below the seat from the buckle 14 and is fixed to a floor panel (not shown) via a seat rail 34 .

(buckle)
The buckle 14 is arranged on the seat width direction outer side (seat side and vehicle width direction inner side) of a seat cushion 32A in the vehicle seat 32 on which the occupant P is seated. 14A is covered with a resin cover 14B, and has a structure in which a tongue plate 16 attached to the webbing 12 engages inside the buckle body portion 14A. The tongue plate 16 is inserted into the buckle 14 and engaged with the buckle 14 when the webbing 12 is attached. Further, when the webbing 12 is removed, the engagement of the tongue plate 16 can be released by a release button (not shown) of the buckle 14 . The buckle 14 is provided with a tongue plate mounting sensor 15 (see FIG. 4), which is configured to output a signal to the control section 24 when the tongue plate 16 is engaged.

(Lift-up mechanism)
The lift-up mechanism section 20 includes a first screw member 40 , a second screw member 42 , a drive mechanism section 44 and a guide member 46 . The first screw member 40 is connected to the seat lower side of the buckle 14 via a rotating portion 48 which will be described later. The first screw member 40 is composed of a long cylindrical member extending from the buckle 14 toward the anchor bracket 18 (see FIG. 1) side. A female screw 50 is formed as a The inside of the cylinder of the first screw member 40 is opened so that the end on the seat lower side in the axial direction can communicate with the outside.

The rotating portion 48 rotates the seat upper end portion 40A of the first screw member 40 arranged between the pair of side wall portions 14AA of the buckle body portion 14A and the pair of side wall portions 14AA in the axial direction. It has a rotary shaft 52 to which it connects. The rotary shaft 52 is formed of a cylindrical member whose longitudinal direction is inclined upward toward the seat rear side as viewed from the side of the vehicle. It is rotatably connected to the seat width direction inner side (vehicle width direction outer side) with respect to the member 40 .

The second screw member 42 is rotatably connected to the anchor bracket 18 (see FIG. 1) through the holding bracket 54 with the seat width direction as the axial direction. The second screw member 42 extends from the anchor bracket 18 toward the buckle 14 side and is composed of a long columnar member having a diameter that can be inserted into the cylindrical interior of the first screw member 40 . An outer peripheral surface of the second screw member 42 is formed with a male screw 56 that is screwed with the female screw 50 of the first screw member 40 . Note that the holding bracket 54 is fastened to the anchor bracket 18 via a rubber bush 58 .

The drive mechanism portion 44 includes a motor 60 , a first gear 62 and a second gear 64 . The motor 60 is attached to the holding bracket 54 at a position adjacent to the second screw member 42, and is arranged so that the drive shaft 66 is parallel to the axial direction of the second screw member 42 when viewed from the side of the vehicle. .

The first gear 62 is attached to the tip of the drive shaft 66 of the motor 60, and is a so-called spur gear formed in a disc shape centering on the axial direction of the drive shaft 66 and having teeth 62A formed on the outer peripheral surface. ing.

The second gear 64 is attached to the longitudinal end of the second screw member 42 on the seat lower side. A so-called spur gear is formed. The teeth 62A of the first gear 62 and the teeth 64A of the second gear 64 are meshed with each other. The force is transmitted to the second screw member 42 so that the second screw member 42 can rotate about the axial direction.

The guide member 46 is configured including a first sliding member 68 and a second sliding member 70 . The first sliding member 68 is provided on the outer peripheral surface 40B of the first screw member 40 connected to the buckle 14, and is composed of a cylindrical member extending along the axial direction of the first screw member 40. there is That is, the first sliding member 68 is provided on the buckle 14 side. The longitudinal end of the cylindrical interior of the first sliding member 68 on the seat lower side is open so as to be able to communicate with the outside.

The second sliding member 70 is provided at a position adjacent to the second screw member 42 in the holding bracket 54, and is composed of a cylindrical member whose longitudinal direction is the axial direction of the first screw member 40. 1 is inserted inside the cylinder of the sliding member 68 . That is, the second sliding member 70 is provided on the anchor bracket 18 side via the holding bracket 54 . With the above configuration, the first sliding member 68 and the second sliding member 70 can move relative to each other along the axial direction of the first screw member 40 . In addition, the second sliding member 70 is configured to face and abut against the cylindrical inner surface 68A as a facing portion of the first sliding member 68 in the rotational direction about the axial direction of the first screw member 40. .

(pretensioner mechanism)
As shown in FIG. 1, the pretensioner mechanism 22 is a device for retracting the buckle 14 by being actuated. The pretensioner mechanism 22 is provided on the seat rail 34 of the vehicle seat 32 . Specifically, the pretensioner mechanism portion 22 has a pretensioner body portion 22A and a retraction guide member 22B, and the pretensioner body portion 22A is formed in a cylindrical shape. It is arranged on the seat lower side of the vehicle seat 32 so that the seat front-rear direction is the longitudinal direction of the pretensioner main body portion 22A. A movable portion (not shown) is provided inside the pretensioner body portion 22A. This movable portion is engaged with an end portion (not shown) on the seat front side of the flexible load transmission member 74 .

The load transmission member 74 is configured in a flexible, elongated shape, spans the buckle 14 and the pretensioner mechanism 22, and is drawn into the pretensioner main body 22A when the pretensioner mechanism 22 is actuated. It is a member. Specifically, the load transmission member 74 is, for example, a wire, and the end portion on the front side of the seat is engaged with the movable portion of the pretensioner body portion 22A from the rear side of the seat. An end portion 74A of the load transmission member 74 on the seat rear side is connected to the buckle 14 via a rotating portion 78 so as to be rotatable about the vehicle width direction as an axial direction. Thereby, the movable portion and the buckle 14 are connected. The length of the load transmission member 74 is set so as not to hinder the movement of the buckle 14 to the uppermost end of the movable range (see the chain double-dashed line in the figure).

A seat rear side portion of the pretensioner mechanism portion 22 is configured by a retraction guide member 22B. The retraction guide member 22B is coupled to the end of the pretensioner main body 22A on the seat rear side, and is formed in a circular shape protruding from the pretensioner main body 22A to the upper side of the seat when viewed from the side of the vehicle. there is A load transmission member 74 is slidable on the outer periphery of the retraction guide member 22B.

The pretensioner mechanism 22 operates upon receiving an operating current from the control unit 24 at the time of a forward movement collision, generates high-pressure gas in the pretensioner main body 22A, and the pressure of the gas pushes the movable portion toward the front side of the seat. , and pulls the buckle 14 toward the front side and the lower side of the seat via the load transmission member 74 (changes from the broken line to the solid line in the drawing).

(collision prediction sensor)
As shown in FIG. 4, the control unit 24 includes a collision prediction sensor 26, a collision detection sensor 28, a tongue plate mounting sensor 15, a seating sensor 33, and a A reclining angle detection sensor 38 is communicably connected. The collision prediction sensor 26 is, for example, a millimeter wave radar, a laser radar, a stereo camera, or the like, and is configured to be capable of outputting a signal to the control unit 24 when a forward movement collision of the vehicle is predicted. The forward movement collision is predicted and a signal is output to the control unit 24 even when the brake sensor detects the operation of the brake pedal or when the accelerator sensor detects the sudden off operation of the accelerator pedal. good. In that case, the above brake sensor or accelerator sensor becomes the collision prediction sensor.

(collision detection sensor)
A collision detection sensor 28 detects the acceleration that occurs in the vehicle due to a forward movement collision. The collision detection sensor 28 is configured to be capable of outputting a signal to the control unit 24 when a forward movement collision of the vehicle is detected.

The seat sensor 33 is provided on the vehicle seat 32 (see FIG. 1) and detects whether or not the passenger P is seated on the vehicle seat 32 . The seating sensor 33 is configured to output a signal to the control unit 24 when the occupant P is seated on the vehicle seat 32 .

(control part)
The control unit 24 includes a CPU (Central Processing Unit) 80 , a ROM (Read Only Memory) 82 , a RAM (Random Access Memory) 84 and a storage 86 . Each component is communicatively connected to each other via a bus 88 .

The CPU 80 is a central processing unit that executes various programs and controls each section. That is, the CPU 80 reads a program from the ROM 82 or the storage 86 and executes the program using the RAM 84 as a work area. The CPU 80 performs control of the above components and various arithmetic processing according to programs recorded in the ROM 82 or the storage 86 . In this embodiment, the ROM 82 or the storage 86 stores an occupant restraint control program for controlling the movement of the buckle 14 and the operation of the pretensioner mechanism 22 of the vehicle seatbelt device 10 .

The ROM 82 stores various programs and various data. The RAM 84 temporarily stores programs or data as a work area. The storage 86 is configured by a HDD (Hard Disk Drive) or SSD (Solid State Drive) and stores various programs including an operating system and various data.

(Functional configuration)
When executing the occupant restraint control program described above, the vehicle seatbelt device 10 uses the hardware resources described above to realize various functions. A functional configuration realized by the vehicle seat belt device 10 will be described.

FIG. 5 is a block diagram showing an example of the functional configuration of the vehicle seatbelt device 10. As shown in FIG.

As shown in FIG. 5, the vehicle seatbelt device 10 includes, as a functional configuration, a seating detection unit 90, a tongue plate attachment detection unit 92, a reclining angle detection unit 94, a collision prediction unit 96, a collision detection unit 98, and a determination unit. 100 and an output section 102 . Each functional configuration is realized by the CPU 80 of the control unit 24 reading out and executing an occupant restraint control program stored in the ROM 82 or the storage 86 (see FIG. 4).

The seating detection unit 90 determines whether or not the occupant P is seated on the vehicle seat 32 based on the signal from the seating sensor 33 and outputs the determination result to the determination unit 100 .

The tongue plate attachment detection unit 92 determines whether or not the tongue plate 16 is attached to the buckle 14 based on the signal from the tongue plate attachment sensor 15 and outputs the determination result to the determination unit 100 .

The reclining angle detector 94 determines whether or not the reclining angle of the seat back 32B of the vehicle seat 32 is greater than or equal to a predetermined angle based on the signal from the reclining angle detection sensor 38 . In this embodiment, as an example, it is determined whether or not the seat has been reclined by 30° or more with respect to the vertical direction. Then, the reclining angle detection section 94 outputs this determination result to the determination section 100 .

The collision prediction unit 96 determines whether or not the collision prediction sensor 26 has predicted a forward movement collision of the vehicle, and outputs the determination result to the determination unit 100 .

The collision detection unit 98 determines whether or not the collision detection sensor 28 has detected a forward movement collision of the vehicle, and outputs the determination result to the determination unit 100 .

The determination unit 100 determines whether or not to operate the pretensioner mechanism unit 22 and moves the buckle 14 based on information from the seating detection unit 90, the tongue plate attachment detection unit 92, the reclining angle detection unit 94, and the collision prediction unit 96. Determine whether or not That is, when the occupant P is seated on the vehicle seat 32 and the tongue plate 16 is attached to the buckle 14 and the seat back 32B is reclined by a predetermined angle or more and a forward movement collision is predicted, the buckle 14 is released. It is determined to move the seat upward. Thereafter, when a forward movement collision is detected, it is determined to operate the pretensioner mechanism 22 . The determination unit 100 outputs determination results to the output unit 102 .

The output unit 102 operates at least one of the motor 60 (see FIG. 2) of the drive mechanism unit 44 and the pretensioner mechanism unit 22 (see FIG. 1) based on the determination result of the determination unit 100 . That is, when the determination unit 100 determines to move the buckle 14 to the upper side of the seat, the output unit 102 rotates the motor 60 in the direction in which the amount of overlap between the first screw member 40 and the second screw member 42 decreases. rotate. On the other hand, when the determination unit 100 determines to move the buckle 14 downward of the seat, the motor 60 is rotated in the direction in which the amount of overlap between the first screw member 40 and the second screw member 42 increases. The basic state of the output unit 102 is a state in which the buckle 14 is positioned at the lowest end of the movable range.

Further, when the determination unit 100 determines to operate the pretensioner mechanism unit 22 , the output unit 102 supplies an operating current to the pretensioner mechanism unit 22 to operate the pretensioner mechanism unit 22 , so that the buckle 14 to the front side of the seat and the lower side of the seat.

(processing flow)
Next, the action of the vehicle seat belt device 10 will be described. FIG. 6 is a flow chart showing the operation flow of the vehicle seatbelt device 10. As shown in FIG. The CPU 80 reads an occupant restraint control program from the ROM 82 or the storage 86, develops it in the RAM 84, and executes it, whereby the buckle 14 is moved and the pretensioner mechanism 22 is operated.

The CPU 80 determines whether or not the passenger P is seated on the vehicle seat 32 (step S100). If the occupant P is not seated on the vehicle seat 32 (step S100: NO), the CPU 80 terminates the process based on the buckle movement control program. On the other hand, if the passenger P is seated on the vehicle seat 32 (step S100: YES), the CPU 80 determines whether the tongue plate 16 is attached to the buckle 14 (step S102). If the tongue plate 16 is not attached to the buckle 14 (step S102: NO), the CPU 80 terminates the process based on the buckle movement control program.

If the tongue plate 16 is attached to the buckle 14 (step S102: YES), the CPU 80 determines whether the reclining angle of the seatback 32B is equal to or greater than a predetermined angle (step S104). If the reclining angle of the seatback 32B is not equal to or greater than the predetermined angle (step S104: NO), the CPU 80 proceeds to the process of step S110, which will be described later.

When the reclining angle of the seatback 32B is equal to or greater than the predetermined angle (step S104: YES), the CPU 80 determines whether or not a forward movement collision has been predicted (step S106). If a forward movement collision has not been predicted (step S106: NO), the CPU 80 returns to the process of step S104. On the other hand, when a forward movement collision is predicted (step S106: YES), the CPU 80 moves the buckle 14 to the upper side of the vehicle (step S108).

The CPU 80 determines whether or not a forward movement collision has been detected (step S110). If forward movement collision is not detected (step S110: NO), the CPU 80 returns to the process of step S104. On the other hand, when forward movement collision is detected (step S110: YES), the CPU 80 activates the pretensioner mechanism 22 (step S112), and then terminates the process based on the buckle movement control program.

(action/effect)
Next, the operation and effects of this embodiment will be described.

Here, using the comparative example shown in FIG. 7, the operation and effects of this embodiment will be described. In addition, the same numbers are attached to the same configuration parts as in the present embodiment, and the description thereof is omitted.

As shown in FIG. 7, in the vehicle seat belt device 200, when a forward movement collision is detected with the tongue plate 16 attached to the buckle 14, the pretensioner mechanism 22 is actuated to keep the lap belt on the occupant. It is pulled in the restraint direction (transition from broken line to solid line in the figure). At this time, when the occupant P is in a comfortable state by reclining the seat back 32B, the pelvis moves toward the front side of the seat and tilts backward compared to the normal seated state, so the lap belt 12A corresponds to the upper side of the pelvis. It becomes easy to hang on the part where it was done. If the buckle 14 is pulled downward in this state, the upper part of the pelvis is pulled downward in the seat.

On the other hand, in this embodiment, as shown in FIG. and The webbing 12 has a lap belt 12A that restrains the waist L or thighs F of the occupant P seated on the vehicle seat 32 having the seat back 32B and the seat cushion 32A. The buckle 14 is engaged with a tongue plate 16 positioned on the side of the seat cushion 32A and attached to the boundary between the lap belt 12A of the webbing 12 and other parts. The buckle 14 can be moved to either a retracted position or a raised position by a lift-up mechanism 20 . The buckle 14 is connected to a pretensioner mechanism 22, and the buckle 14 is pulled toward the seat front side and the seat lower side on the seat cushion 32A side when the pretensioner mechanism 22 operates. The control unit 24 causes the lift-up mechanism unit 20 to move the buckle 14 to the raised position (see the two-dot chain line in the figure) when a forward movement collision is predicted in a state where the reclining angle of the seatback 32B is equal to or greater than a predetermined angle. . After that, the control unit 24 operates the pretensioner mechanism unit 22 when a vehicle collision is detected. That is, by moving the buckle 14 to the raised position by the lift-up mechanism 20, the tension of the lap belt 12A is weakened. By activating the pretensioner mechanism 22 in this state, the buckle 14 and the lap belt 12A can be moved farther toward the seat front than when the tension of the webbing 12 is not weakened. Therefore, even in a comfortable state in which the pelvis moves toward the front side of the seat and tilts backward compared to the normal seated state, the lap belt 12A can be easily moved to a position corresponding to the lower part of the pelvis of the occupant P. It can be retracted to the seat lower side at a position corresponding to the lower part. As a result, the pelvis of the occupant P can be tilted forward to make it difficult for the lap belt 12A of the webbing 12 to come off the pelvis, thereby suppressing the occurrence of the submarine phenomenon. As a result, it is possible to effectively suppress the occurrence of the submarine phenomenon at the time of a forward-moving collision, including the occupant P in a comfortable state.

Further, when the reclining angle of the seat back 32B is within the predetermined angle, the pretensioner mechanism 22 operates without moving the buckle 14 to the raised position. That is, when the reclining angle of the seat back 32B is within a predetermined angle, the occupant P is generally in a seated state. 22, there is no need to move the lap belt 12A to the front side of the seat. Therefore, even if the pretensioner mechanism 22 is operated without moving the buckle 14 to the raised position, the lap belt 12A can be pulled in toward the lower side of the seat at the portion corresponding to the lower part of the pelvis of the occupant P. Further, by moving the buckle 14 to the raised position, it is possible to minimize the temporary decrease in the occupant restraint force due to the weakening of the tension of the lap belt 12A.

Furthermore, a first screw member 40 is connected to the buckle 14 engaged with the tongue plate 16 attached to the webbing 12 of the vehicle seat belt device 10, and the first screw member 40 is shown in FIG. , a female thread 50 is formed extending toward the anchor bracket 18 and extending in the axial direction. On the other hand, a second screw member 42 is connected to the anchor bracket 18 , and the second screw member 42 is formed with a male screw 56 that is screwed together with the first screw member 40 . Further, the vehicle seat belt device 10 is provided with a guide member 46. The guide member 46 includes a first sliding member 68 provided on the buckle 14 side and a first sliding member 68 provided on the anchor bracket 18 side. It has a sliding member 68 and a second sliding member 70 that is slidable in the axial direction. The first sliding member 68 is provided with a cylindrical inner surface 68A facing the second sliding member 70 in the rotational direction about the axial direction. Accordingly, the guide member 46 restricts the relative rotation of the first screw member 40 and the second screw member 42 about the axial direction. Therefore, when the second screw member 42 is rotated in the axial direction by the drive mechanism portion 44 , the first screw member 40 can be moved relative to the second screw member 42 along the axial direction. That is, the buckle 14 can be moved between the extended state in which the buckle 14 is moved substantially above the seat as shown in FIG. 2 and the contracted state in which it is moved substantially below the seat as shown in FIG. . As a result, the tongue plate 16 can be easily attached and detached by moving the buckle 14 to the upper side of the seat. In addition, since the first screw member 40 and the second screw member 42 are coaxially arranged by screwing, the space orthogonal to the axial direction of the first screw member 40 and the second screw member 42 is minimized. can do. This facilitates miniaturization.

Furthermore, since the first threaded member 40 moves relative to the second threaded member 42 in the axial direction by screwing, it is not necessary to rotate the drive mechanism section 44 at a high output. Further, since the first screw member 40 is connected to the buckle 14, when a collision load acts in the direction of pulling out the buckle 14 toward the front side of the seat at the time of a forward movement collision, the first screw member 40 and this are screwed together. A collision load acts on the second screw member 42 along the axial direction. Therefore, the collision load is input in a direction different from the rotation direction of the motor 60 of the drive mechanism portion 44 that rotates the first screw member 40 or the second screw member 42 about the axial direction. For this reason, a stopper mechanism for suppressing the movement of the buckle 14 when a collision load acts in the direction of pulling out the buckle 14 toward the seat front side, or a stopper mechanism for moving the buckle 14 in the direction opposite to the direction in which the collision load acts to prevent the collision load. A high-output drive source for canceling is not required. That is, it is possible to reduce the weight and size of the drive mechanism section 44 and the like. As a result, the tongue plate 16 and thus the webbing 12 can be easily attached and detached while reducing weight and improving mountability.

Further, the first screw member 40 is connected to the seat lower side of the buckle 14 via the rotating portion 48 , so that the buckle 14 can be moved to the seat width direction inner side (vehicle width direction outer side) with respect to the first screw member 40 . ) is rotatably connected to the Therefore, the webbing 12 easily follows the occupant P even when the buckle 14 moves due to extension and contraction of the vehicle seat belt device 10 . Thereby, the fitting property of the webbing 12 to the passenger P can be improved. Furthermore, since the retaining bracket 54 is fastened to the anchor bracket 18 via the rubber bush 58 , flexibility in the seat width direction of the buckle 14 is imparted via the retaining bracket 54 and the guide member 46 . Thereby, the fitting property of the webbing 12 to the passenger P can be further improved.

In the above-described embodiment, the lift-up mechanism portion 20 is configured such that the female screw 50 is formed on the first screw member 40 and the male screw 56 is formed on the second screw member 42. Alternatively, the first screw member 40 may be formed with the male thread 56 and the second screw member 42 may be formed with the female thread 50 . Moreover, although it is configured to rotate the second screw member 42 by the drive mechanism portion 44 , the configuration is not limited to this, and the first screw member 40 may be rotated. Furthermore, the buckle 14 may be moved in the vertical direction of the seat by using other mechanisms such as wires instead of the first screw member 40 and the second screw member 42 .

In addition, the first sliding member 68 is formed in a cylindrical shape, and the second sliding member 70 is formed in a columnar shape to be inserted into the cylindrical interior of the first sliding member 68. Either one of the first sliding member 68 and the second sliding member 70 is provided with a facing portion facing the other of the first sliding member 68 and the second sliding member 70 in the direction of rotation about Other configurations are also possible.

Further, when the reclining angle of the seat back 32B is equal to or greater than a predetermined angle and a forward movement collision is predicted, the buckle 14 is moved to the upper side of the seat. 32 in the vertical direction of the seat is also detected, the position of the lumbar region L of the occupant P is estimated from these, and the buckle 14 is moved upward toward the position corresponding to the estimated lumbar region L. . Further, a pressure detection sensor is provided on the seat surface of the seat cushion 32A, and the position of the waist L of the occupant P on the seat cushion is estimated from the detection result of this pressure detection sensor. may be moved to the upper side of the seat. Further, an imaging device is provided in the vehicle to photograph the occupant P, the position of the lumbar region L of the occupant P is estimated by performing image analysis of the photographed image, and the buckle 14 is seated at a position corresponding to the estimated lumbar region L. It is good also as a structure moved upwards.

Furthermore, the control unit 24 is configured to move the buckle 14 to the raised position by the lift-up mechanism unit 20 when a forward movement collision is predicted. may be photographed and the buckle 14 may be moved to the raised position by the lift-up mechanism 20 when danger is predicted, such as when the occupant P is dozing off.

In addition, the vehicle seat 32 has the front side of the seat substantially aligned with the front side of the vehicle, but the present invention is not limited to this. In this case, the "forward movement collision" is a collision type other than a frontal collision, and a collision type in which an occupant seated on the vehicle seat 32 moves inertially to the front side of the seat at the time of collision (for example, the vehicle seat 32 If the front side of the seat is substantially aligned with the rear side of the vehicle, a rear-end collision occurs.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above, and it is possible to implement various modifications other than the above without departing from the spirit of the present invention. Of course.

10 vehicle seat belt device 12 webbing 12A lap belt 14 buckle 16 tongue plate 20 lift-up mechanism 22 pretensioner mechanism 24 control unit 32 vehicle seat 32A seat cushion 32B seat back F thigh L waist P occupant

Claims (1)

a webbing having a lap belt for restraining the waist or thighs of an occupant seated on a vehicle seat having a seat back and a seat cushion;
a buckle positioned on the side of the seat cushion and engaged with a tongue plate attached to the boundary between the lap belt and other parts of the webbing;
a lift-up mechanism that moves the buckle to one of a retracted position and a raised position located on the upper side of the vehicle with respect to the retracted position;
a pretensioner mechanism that is connected to the buckle and operates to pull the buckle toward the seat front side and the seat lower side of the seat cushion;
When the reclining angle of the seat back is detected, and danger is predicted when the reclining angle is equal to or greater than a predetermined angle, the lift-up mechanism moves the buckle to the raised position, and then a vehicle collision is detected. a control unit that operates the pretensioner mechanism unit when the
A seat belt device for a vehicle.

Images