JP2017136957A - Webbing take-up device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a webbing take-up device capable of absorbing a tensile force of a webbing having a size corresponding to increase and decrease of at least one of a drawing speed of a webbing and a drawing acceleration of the webbing.SOLUTION: According to a webbing take-up device 10, when a webbing drawing speed is low, a pressing part 54 of an FL piece 50 is brought into contact with the other side of an elastic piece 44 of an FL member 40, and in this state, the elastic piece 44 of the FL member 40 is pressed by the pressing part 54 of the FL piece 50 and elastically deformed. On the other hand, when the webbing drawing speed is high, the pressing part 54 of the FL piece 50 is brought into contact with one side end side of the elastic piece 44 of the FL member 40, and in this state, the elastic piece 44 of the FL member 40 is pressed by the pressing part 54 of the FL piece 50 and elastically deformed. Therefore, the absorption amount of a tensile force of a webbing is larger when the webbing drawing speed is higher.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a webbing take-up device that can absorb part of the tensile force of a webbing.

  There is a webbing take-up device including two or more load absorbing means capable of absorbing a part of the tensile force applied to the webbing in a vehicle emergency. In this type of webbing take-up device, when a predetermined condition based on the weight of the occupant, the deceleration of the vehicle, the webbing withdrawal amount, etc. is not satisfied, only one load absorbing means is operated, and the predetermined condition is satisfied. When the condition is satisfied, the absorption amount of the tensile force applied to the webbing is changed by operating only two or more load absorbing means (see Patent Document 1 below as an example).

  In this type of webbing take-up device, the amount of tensile force absorbed by the load absorbing means is determined by the number of load absorbing means to be operated, and is increased or decreased step by step by the number of load absorbing means.

JP 2010-137837 A

  An object of the present invention is to obtain a webbing take-up device that can absorb the tensile force of a webbing having a magnitude corresponding to increase / decrease of at least one of webbing withdrawal speed and webbing withdrawal acceleration in consideration of the above facts.

  The webbing take-up device according to claim 1, wherein the webbing is rotated in the pull-out direction when the webbing is pulled toward the distal end in the longitudinal direction, the support member that supports the spool, and the rotation that is rotated by the rotation of the spool. A member, a fixing member supported by the supporting member on the radial side of the rotating member, and one end of the rotating member and the fixing member are connected to each other, and the other side is the other of the rotating member and the fixing member. It can be deformed by applying a force along the circumferential direction of the rotating member, and deformed by changing the position where the force is applied to the other side than the one end. A deforming portion that requires less force, a pressing portion that is provided on the other of the rotating member and the fixing member and that can press the deforming portion by rotation of the rotating member, and the pressing portion Changing means for changing the distance between the pressing position of the deformable portion and one side end portion of the deformable portion according to at least one of the rotational speed of the rotating member and the rotational acceleration of the rotating member. ing.

  According to the webbing take-up device of the first aspect, the distance between the pressing position of the deforming portion in the pressing portion and the one side end of the deforming portion is determined by the changing means by the rotational speed of the rotating member or the rotational acceleration of the rotating member. It can be changed according to the size. For this reason, the magnitude | size of the force required for a deformation | transformation of a deformation | transformation part can be changed according to the rotation speed of a rotation member, or the magnitude | size of the rotation acceleration of a rotation member. As a result, of the tensile force when the webbing is pulled to the front end side in the longitudinal direction, the magnitude of the tensile force absorbed by the deformation of the deformed portion is the magnitude of at least one of the webbing withdrawal speed and the webbing withdrawal acceleration. Can be changed according to.

  The webbing take-up device according to a second aspect is the webbing take-up device according to the first aspect, wherein the deformation of the deforming portion by being pressed by the pressing portion is an elastic deformation.

  According to the webbing take-up device of the second aspect, the deformation of the deforming portion caused by being pressed by the pressing portion is elastic deformation. For this reason, when the pressing portion to the deforming portion is eliminated, the deforming portion is restored. Thereby, for example, even if the rotation of the rotating member exceeds one rotation, the deforming portion can be deformed by the pressing of the pressing portion.

  A webbing take-up device according to a third aspect is the webbing take-up device according to the first or second aspect, wherein at least one of the pressing portion and the deforming portion is provided.

  In the webbing take-up device according to claim 3, at least one of the pressing portion and the deforming portion is provided. For this reason, the average value of the magnitude of the tensile force of the webbing absorbed by the deformation of the deformation portion while the rotating member is rotated can be increased.

  The webbing take-up device according to a fourth aspect is the webbing take-up device according to any one of the first to third aspects, wherein the plurality of pressing portions have a predetermined angle around the central axis of the rotating member. A plurality of the deforming portions are provided for each angle different from the predetermined angle around the central axis of the rotating member.

  In the webbing take-up device according to claim 4, the plurality of pressing portions are provided at predetermined angles around the central axis of the rotating member, and the plurality of deforming portions have the predetermined angle around the central axis of the rotating member. Are provided at different angles. Thereby, the timing at which at least one of the plurality of deforming portions is pressed by the pressing portion can be shifted from the timing at which the other at least one of the plurality of deforming portions is pressed by the pressing portion. Thereby, it is possible to suppress an increase in the difference between the maximum value and the minimum value of the magnitude of the tensile force of the webbing absorbed by the deformation of the deformation portion while the rotation member is rotated.

  As described above, the webbing take-up device according to the present invention can absorb the tensile force of the webbing having a magnitude corresponding to the increase / decrease of at least one of the webbing withdrawal speed and the webbing withdrawal acceleration.

It is a front view of the webbing winding device concerning a 1st embodiment. It is a disassembled perspective view of the 2nd force limiter mechanism of the webbing winding device concerning a 1st embodiment. It is a side view of the 2nd force limiter mechanism of the webbing winding device concerning a 1st embodiment. It is an enlarged side view which shows the state which the press part of the force limiter piece contact | abutted to the elastic piece of the force limiter member in the state where webbing extraction | drawer speed is slow. FIG. 5 is an enlarged side view corresponding to FIG. 4 showing a state where the elastic piece of the force limiter member is pressed by the pressing portion of the force limiter piece and elastically deformed in a state where the webbing pull-out speed is low. FIG. 5 is an enlarged side view corresponding to FIG. 4 illustrating a state in which the pressing portion of the force limiter piece is in contact with the elastic piece of the force limiter member in a state where the webbing pull-out speed is high. FIG. 6 is an enlarged side view corresponding to FIG. 5 showing a state where the elastic piece of the force limiter member is pressed by the pressing portion of the force limiter piece and elastically deformed in a state where the webbing pull-out speed is high. It is a disassembled perspective view of the 2nd force limiter mechanism of the webbing winding device concerning a 2nd embodiment. It is an enlarged side view which shows the state which the press part of the force limiter piece contact | abutted to the elastic piece of the force limiter member in the state where webbing extraction acceleration is small. FIG. 10 is an enlarged side view corresponding to FIG. 9 showing a state where the elastic piece of the force limiter member is pressed by the pressing portion of the force limiter piece and elastically deformed in a state where the webbing pull-out acceleration is small. FIG. 10 is an enlarged side view corresponding to FIG. 9 illustrating a state where the pressing portion of the force limiter piece is in contact with the elastic piece of the force limiter member in a state where the webbing pull-out acceleration is large. FIG. 11 is an enlarged side view corresponding to FIG. 10 showing a state where the elastic piece of the force limiter member is pressed by the pressing portion of the force limiter piece and elastically deformed in a state where the webbing pull-out acceleration is large.

  Next, each embodiment of the present invention will be described with reference to FIGS. In each figure, the arrow FR indicates the front side of the vehicle to which the webbing retractor 10 is applied, the arrow OUT indicates the vehicle width direction outer side, and the arrow UP indicates the vehicle upper side. In describing each embodiment, the same reference numerals are given to the same parts as those in the previous embodiment, and the detailed description thereof is omitted. .

<Configuration of First Embodiment>
As shown in FIG. 1, the webbing take-up device 10 according to the first embodiment includes a frame 12 as a support member. The frame 12 is fixed to a vehicle lower portion of a center pillar (not shown) as a vehicle body. The frame 12 includes leg plates 14 and 16, and the leg plate 14 and the leg plate 16 are opposed to each other substantially in the vehicle front-rear direction.

  The frame 12 is provided with a spool 18. The spool 18 is formed in a substantially cylindrical shape. The center axis direction of the spool 18 is along the opposing direction of the leg plate 14 and the leg plate 16 (that is, substantially the vehicle front-rear direction), and the spool 18 is rotatable around the center axis. A longitudinal base end portion of the long webbing 20 is locked to the spool 18, and when the spool 18 is rotated in the winding direction (the arrow A direction in FIG. 2 and the like), the webbing 20 is moved in the longitudinal direction. It is wound on the spool 18 from the base end side. The front end side of the webbing 20 in the longitudinal direction extends from the spool 18 toward the vehicle upper side, and the front end side of the webbing 20 in the longitudinal direction is formed on a through anchor (not shown) supported on the center pillar on the vehicle upper side of the frame 12. It is turned back to the vehicle lower side through the slit hole.

  Furthermore, the longitudinal direction front-end | tip part of the webbing 20 is latched by the anchor plate (illustration omitted). The anchor plate is formed of a metal plate material such as iron, and is fixed to a vehicle floor (not shown) or a skeleton member of a sheet (not shown) corresponding to the webbing take-up device 10.

  The vehicle seat belt device to which the webbing retractor 10 is applied includes a buckle device (not shown). The buckle device is provided on the inner side in the vehicle width direction of the seat to which the webbing take-up device 10 is applied. In a state where the webbing 20 is wound around the body of the occupant seated on the seat, the tongue (not shown) provided on the webbing 20 is engaged with the buckle device, so that the webbing 20 is mounted on the body of the occupant. .

  On the other hand, the webbing take-up device 10 includes a lock mechanism 22. The lock mechanism 22 includes a lock base 24. The lock base 24 is rotatably provided around the center axis of the spool 18 on the vehicle rear side of the spool 18. The lock base 24 is provided with a lock pawl 26. The lock pawl 26 is movable outward in the rotational radius direction of the lock base 24. In the lock base 24, an arrangement portion of the lock pawl 26 passes through a ratchet hole 28 formed in the leg plate 14 of the frame 12, and when the lock pawl 26 is moved outward in the rotational radius direction of the lock base 24, The ratchet teeth formed on the lock pawl 26 mesh with the ratchet teeth of the ratchet hole 28 of the leg plate 14 of the frame 12. As a result, the rotation of the lock base 24 in the pulling direction opposite to the winding direction (direction of arrow B in FIG. 2 and the like) is restricted.

  Further, the webbing take-up device 10 includes a torsion bar 30 that constitutes a first force limiter mechanism of the force limiter. The torsion bar 30 is formed in a bar shape that is substantially long in the vehicle longitudinal direction. A vehicle front side portion of the torsion bar 30 is disposed inside the spool 18 and is connected to the spool 18 in a state where relative rotation with respect to the spool 18 is prevented. On the other hand, the vehicle rear side portion of the torsion bar 30 is disposed inside the lock base 24 and connected to the lock base 24 in a state in which relative rotation with respect to the lock base 24 is prevented.

  In other words, the lock base 24 is connected to the spool 18 in a state in which relative rotation with the spool 18 is prevented by the torsion bar 30, and the lock base 24 is rotated together with the spool 18. Therefore, when the rotation of the lock base 24 in the pull-out direction is restricted by the ratchet teeth of the lock pawl 26 of the lock mechanism 22 engaging the ratchet teeth of the ratchet hole 28 of the leg plate 14 of the frame 12, the spool 18 Rotation in the pull-out direction is limited. In this manner, the pulling of the webbing 20 from the spool 18 is restricted by restricting the rotation of the spool 18 in the drawing direction.

  Further, a spring housing 32 is provided on the vehicle rear side of the leg plate 14 of the frame 12. Spool urging means (not shown) such as a mainspring spring is provided inside the spring housing 32, and the spool 18 is urged in the winding direction by the urging force of the spool urging means.

  A sensor mechanism 34 is provided between the leg plate 14 of the frame 12 and the spring housing 32. The sensor mechanism 34 is activated in the event of a vehicle emergency such as a vehicle collision. When the lock base 24 of the lock mechanism 22 is rotated in the pull-out direction in the operation state of the sensor mechanism 34, the lock pawl 26 of the lock mechanism 22 is moved outward in the rotational radius direction of the lock base 24, and the lock pawl of the lock mechanism 22 is The 26 ratchet teeth mesh with the ratchet teeth of the ratchet hole 28 of the leg plate 14 of the frame 12.

  Further, a pretensioner 36 is provided between the leg plate 14 of the frame 12 and the sensor mechanism 34. The pretensioner 36 is activated in the event of a vehicle emergency such as a vehicle collision, and when the pretensioner 36 is activated, the spool 18 is rotated in the winding direction. As a result, the webbing 20 is wound around the spool 18 and the occupant's body is restrained by the webbing 20 with a greater restraining force than before.

  On the other hand, the webbing take-up device 10 includes a second force limiter mechanism 38 (hereinafter, the second force limiter mechanism 38 is referred to as a “second FL mechanism 38”). The second FL mechanism 38 includes a force limiter member 40 (hereinafter, the force limiter member 40 is referred to as “FL member 40”) as a fixing member. As shown in FIGS. 2 and 3, the FL member 40 includes a ring portion 42. The ring portion 42 is formed in a cylindrical shape in a side view (as viewed in the vehicle front-rear direction). The ring portion 42 is disposed coaxially with the spool 18 and is fixed to the leg plate 16 inside the frame 12 (between the leg plate 14 and the leg plate 16).

  The FL member 40 includes a plurality of elastic pieces 44 each serving as a deforming portion. These elastic pieces 44 are formed around the center line of the ring portion 42 at a predetermined angle, in particular at a constant angle in the present embodiment. These elastic pieces 44 are formed by bending a portion of the ring portion 42 on the vehicle rear side from the vehicle front-rear direction intermediate portion to the inside of the ring portion 42 in the radial direction. The elastic piece 44 has a plate shape with a substantially equal thickness dimension from one side end of the ring portion 42 side to the other side end on the opposite side. One end portion of the elastic piece 44 is connected to the ring portion 42, and when the circumferential force of the ring portion 42 is input to the other side portion of the elastic piece 44, the elastic piece 44 has one side end portion. Is elastically deformed around an axis parallel to the center line of the ring portion 42.

  A force limiter base 46 as a rotating member (hereinafter, the force limiter base 46 is referred to as “FL base 46”) is provided inside the ring portion 42 of the FL member 40 in the radial direction. The FL base 46 is formed in a disk shape, and is arranged coaxially with the spool 18 on the vehicle front side of the spool 18. As shown in FIG. 1, the vehicle rear side portion of the FL base 46 is inside the spool 18, and the FL base 46 is prevented from rotating relative to the spool 18. For this reason, the FL base 46 is rotated together with the spool 18.

  As shown in FIGS. 2 and 3, the FL base 46 is formed with a plurality of piece receiving grooves 48. These piece receiving grooves 48 are formed around the central axis of the FL base 46 at predetermined angles. In particular, in the present embodiment, between the piece receiving grooves 48 adjacent to each other around the central axis of the FL base 46. The angle is the same as the angle between the elastic pieces 44 adjacent to each other around the center line of the ring portion 42 in the FL member 40. The piece receiving grooves 48 are substantially rectangular in a side view (as viewed in the vehicle front-rear direction), and the longitudinal direction of the piece receiving grooves 48 is the radial direction of the FL base 46. These piece receiving grooves 48 are opened at the outer peripheral portion of the FL base 46 and are also opened at the vehicle front side surface of the FL base 46.

  A force limiter piece 50 (hereinafter, the force limiter piece 50 is referred to as an “FL piece 50”) that constitutes a changing unit is provided inside the piece receiving grooves 48. The FL piece 50 includes a piece main body 52. The piece body 52 is formed in a block shape, and the longitudinal direction of the piece body 52 is along the longitudinal direction of the piece receiving groove 48 of the FL base 46. Both side surfaces in the width direction of the piece main body 52 are in contact with both side surfaces in the width direction inside the piece accommodating groove 48 of the FL base 46, and the FL piece 50 is arranged on both side surfaces in the width direction inside the piece accommodating groove 48. It is guided and can slide in the longitudinal direction of the piece receiving groove 48 (that is, the radial direction of the FL base 46).

  The FL piece 50 includes a pressing portion 54. The pressing portion 54 is located at one end in the longitudinal direction of the piece body 52 of the FL piece 50 (a radially outer end of the FL base 46 in the piece body 52). Is formed. The pressing portion 54 is formed in a substantially triangular shape when viewed from the side (viewed in the vehicle front-rear direction), and the radial dimension of the FL base 46 in the pressing portion 54 is one side in the width direction of the piece main body 52 (the drawing direction). Side). When the FL piece 50 is slid beyond the FL base 46 in the radial direction by a predetermined stroke or more, the pressing portion 54 faces the elastic piece 44 of the FL member 40 in the circumferential direction of the FL base 46.

  Further, the FL piece 50 includes a contact piece 56. The contact piece 56 is formed on the vehicle rear side surface of the piece main body 52 at the longitudinal base end of the piece main body 52 of the FL piece 50 (the radially inner end of the FL base 46 in the piece main body 52). The contact piece 56 is located inside a piece biasing spring accommodating groove 58 formed in the FL base 46. The piece biasing spring accommodation groove 58 is opened at the bottom surface (vehicle front side surface) inside the piece accommodation groove 48 of the FL base 46. The piece urging spring accommodating groove 58 is rectangular in a side view (as viewed in the vehicle front-rear direction), and the longitudinal direction of the piece urging spring accommodating groove 58 is the longitudinal direction of the piece accommodating groove 48 of the FL base 46. It is along.

  A piece urging spring 60 that constitutes a changing means together with the FL piece 50 is provided inside the piece urging spring accommodating groove 58. These piece urging springs 60 are compression coil springs, and the spring constant of each piece urging spring 60 is set to be approximately the same. One end of the piece biasing spring 60 is in contact with the radially outer surface of the FL base 46 inside the piece biasing spring accommodating groove 58 of the FL base 46, and the other end of the piece biasing spring 60 is the FL piece. 50 contact pieces 56 are in contact with each other. For this reason, the FL piece 50 is urged radially inward of the FL base 46 by the urging force of the piece urging spring 60.

  Further, the second FL mechanism 38 includes a blocking member 62. The blocking member 62 includes a disk portion 64. The disc portion 64 is formed in a disc shape, and a circular hole 66 is formed coaxially with the outer peripheral portion of the disc portion 64 at the center side of the disc portion 64. A blocking member support portion 68 (see FIG. 1) formed on the rear surface of the FL base 46 passes through the circular hole 66 of the disk portion 64, and the blocking member 62 supports the blocking member of the FL base 46. The portion 68 is rotatably supported on the same axis as the FL base 46.

  Further, the blocking member 62 includes a plurality of blocking pieces 70. These blocking pieces 70 extend from the outer peripheral portion of the disk portion 64 of the blocking member 62 to the vehicle front side. These blocking pieces 70 are formed at constant angles around the center of the disk portion 64 of the blocking member 62, and the angle between adjacent blocking pieces 70 around the center of the disk portion 64 of the blocking member 62 is The angle is the same as the angle between adjacent piece receiving grooves 48 around the central axis of the FL base 46. These blocking pieces 70 are opposed to the opening of the piece receiving groove 48 on the outer peripheral surface of the FL base 46 in the initial state of the blocking member 62, and therefore, in the initial state of the blocking member 62, The sliding of the FL piece 50 outward in the radial direction is blocked by the blocking piece 70 of the blocking member 62.

  Further, a blocking member abutting portion 72 is formed on the disc portion 64 of the blocking member 62. The blocking member abutting portion 72 has a rectangular plate shape, and the blocking member abutting portion 72 extends from the disc portion 64 to the vehicle front side, and is inside the blocking member biasing spring accommodating hole 74 formed in the FL base 46. In. A blocking member biasing spring 76 is provided inside the blocking member biasing spring accommodating hole 74 of the FL base 46. The blocking member biasing spring 76 is a compression coil spring, and one end of the blocking member biasing spring 76 is brought into contact with the side surface in the winding direction inside the blocking member biasing spring accommodating hole 74 of the FL base 46. The other end of the blocking member biasing spring 76 is in contact with the blocking member contact portion 72 of the blocking member 62.

  For this reason, the blocking member 62 is biased in the pulling direction with respect to the FL base 46 by the biasing force of the blocking member biasing spring 76, and the blocking member 62 is biased by the biasing force of the blocking member biasing spring 76 from the initial state. When the FL base 46 is rotated in the pulling direction, the blocking piece 70 of the blocking member 62 is moved in the pulling direction from the opening of the piece receiving groove 48 on the outer peripheral surface of the FL base 46. As a result, the slide blocking state of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released.

  The second FL mechanism 38 includes a holding member 78 as a blocking member rotation limiting unit. As shown in FIG. 1, the holding member 78 has a long wire shape in the central axis direction of the spool 18. Corresponding to the holding member 78, a holding member insertion hole 80 is formed in the spool 18. The holding member insertion hole 80 is formed on the radially outer side of the spool 18 with respect to the center of the spool 18 and penetrates the spool 18 in the central axis direction of the spool 18. The holding member 78 is disposed through the holding member insertion hole 80 of the spool 18, and the vehicle rear side end portion of the spool 18 is held by the lock base 24 of the lock mechanism 22. For this reason, when the spool 18 is rotated relative to the lock base 24 in the pull-out direction, the holding member 78 is pulled out from the vehicle rear side end portion of the holding member insertion hole 80 of the spool 18, and the vehicle rear side surface of the spool 18. It is accommodated in a ring-shaped holding member accommodation groove 82 formed in the above.

  On the other hand, the vehicle front side end portion of the holding member 78 protrudes from the vehicle front side end portion of the holding member insertion hole 80 of the spool 18. Corresponding to the vehicle front side end portion of the holding member 78, a blocking member hole portion 84 is formed in the disc portion 64 of the blocking member 62, and an FL base hole portion 86 is formed in the FL base 46. ing. The front end portion of the holding member 78 in the vehicle passes through the blocking member hole 84 of the blocking member 62 and enters the FL base hole 86 of the FL base 46, whereby the relative rotation of the blocking member 62 with respect to the FL base 46 is prevented. The blocking member 62 is held in the initial state until the vehicle front side end portion of the holding member 78 is moved to the vehicle rear side from the blocking member hole portion 84 of the blocking member 62.

<Operation and Effect of First Embodiment>
Next, the operation and effect of the present embodiment will be described.

  In the webbing retractor 10, the sensor mechanism 34 is activated in the event of a vehicle emergency such as a vehicle collision. In this state, when the lock base 24 of the lock mechanism 22 is rotated together with the spool 18, The lock pawl 26 is moved outward of the lock base 24 in the rotational radius direction. As a result, when the ratchet teeth of the lock pawl 26 of the lock mechanism 22 mesh with the ratchet teeth of the ratchet hole 28 of the leg plate 14 of the frame 12, the rotation of the lock mechanism 22 in the pull-out direction of the lock mechanism 24 is limited. Rotation in the pull-out direction is limited. As a result, the withdrawal of the webbing 20 from the spool 18 is restricted, the occupant's body is restrained by the webbing 20, and the inertial movement of the occupant's body toward the front of the vehicle is prevented by the webbing 20.

  In this state, when the webbing 20 is pulled by the occupant's body and the tensile force exceeds the mechanical strength of the torsion bar 30 of the first force limiter mechanism of the force limiter, the lock base with limited rotation in the pull-out direction is limited. 24, the spool 18 is rotated in the pull-out direction. As a result, the torsion bar 30 of the first force limiter mechanism is twisted and deformed. The spool 18 is rotated in the pull-out direction by the amount of torsional deformation of the torsion bar 30, and the webbing 20 is pulled out from the spool 18 by the rotation angle in the pull-out direction of the spool 18 and is applied to the webbing 20 from the occupant's body. A part of the tensile force is applied to the torsion bar 30 and is absorbed.

  Thus, when the spool 18 is rotated relative to the lock base 24 of the lock mechanism 22 in the pull-out direction, the holding member 78 of the second FL mechanism 38 of the force limiter is moved to the vehicle rear side. Accordingly, when the vehicle front side end portion of the holding member 78 is moved to the vehicle rear side from the blocking member hole portion 84 of the blocking member 62 of the second FL mechanism 38, the holding member 78 holds the blocking member 62 in the initial state. Is released, and the blocking member 62 is rotated in the pull-out direction with respect to the FL base 46 of the second FL mechanism 38 by the biasing force of the blocking member biasing spring 76. As a result, the blocking piece 70 of the blocking member 62 is moved in the pulling direction from the opening of the piece receiving groove 48 on the outer peripheral surface of the FL base 46, and the slide blocking state of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released. Is done.

  In this state, when the FL base 46 is rotated in the pull-out direction together with the spool 18, a centrifugal force is applied to the FL piece 50. When this centrifugal force exceeds the urging force of the piece urging spring 60, the FL piece 50 is slid outward in the radial direction of the FL base 46. When the FL piece 50 is moved outward in the radial direction of the FL base 46 for a certain stroke or more, the pressing portion 54 of the FL piece 50 is opposed to the elastic piece 44 of the FL member 40 in the circumferential direction of the FL base 46.

  When the FL base 46 is further rotated in the pulling direction together with the spool 18 in this state, as shown in FIG. 4, the tip end portion (the pulling direction side end portion) of the pressing portion 54 of the FL piece 50 is moved to the FL member 40. As shown in FIG. 5, the elastic piece 44 of the FL member 40 rotates around the one end portion of the elastic piece 44 by the pressing force from the pressing portion 54 of the FL piece 50. Elastically deformed to be moved. Part of the rotational force in the pull-out direction of the spool 18, that is, part of the tensile force applied to the webbing 20 from the occupant's body is subjected to elastic deformation of the elastic piece 44 of the FL member 40 and absorbed. .

  Meanwhile, when the webbing 20 is quickly pulled out in the state where the blocking of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released, and the FL base 46 is further rotated in the pulling direction together with the spool 18, the FL piece. The centrifugal force acting on 50 increases. When such a large centrifugal force is applied to the FL piece 50, as shown in FIG. 6, the sliding amount of the FL piece 50 toward the outside in the radial direction of the FL base 46 increases, and the pressing portion 54 of the FL piece 50. Is approached to the ring portion 42 of the FL member 40.

  In this state, when the FL base 46 is rotated together with the spool 18 in the pulling direction, the FL piece 50 is pressed on the one end side of the elastic piece 44 of the FL member 40 as compared with the case where the centrifugal force is small (see FIG. 5). As shown in FIG. 7, the blocking piece 70 of the blocking member 62 is attached to one end of the elastic piece 44 by the pressing force from the pressing section 54 of the FL piece 50. It is elastically deformed so as to rotate about the center.

  Here, one end portion of the elastic piece 44 of the FL member 40 becomes a center of rotation when the elastic piece 44 is elastically deformed. The elastic piece 44 of the FL member 40 is elastically deformed by the pressing force received from the pressing portion 54 of the FL piece 50, but the FL member 40 becomes closer as the pressing portion 54 of the FL piece 50 approaches the ring portion 42 of the FL member 40. The pressing force required for elastic deformation of the elastic piece 44 increases.

  Accordingly, in the present embodiment, when the FL base 50 is rotated in the pulling direction together with the spool 18 in a state where the blocking of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released, that is, the webbing 20 is pulled out. The faster the speed and the faster the rotational speed of the spool 18 in the pull-out direction, the greater the pressing force required to elastically deform the elastic piece 44 of the FL member 40, and elastically deform the elastic piece 44 of the FL member 40. The amount of absorption of the rotational force in the pull-out direction of the spool 18 due to the above, that is, the amount of absorption of the tensile force applied to the webbing 20 from the body of the passenger increases.

  Accordingly, for example, the rotation speed of the spool 18 in the pulling-out direction when the occupant's body pulls the webbing 20 in a state where the occupant's body is large and the blocking of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released. Is larger, the tensile force applied to the webbing 20 from the body of the passenger can be absorbed by the elastic piece 44 of the FL member 40 by elastic deformation.

  In the present embodiment, the magnitude of the centrifugal force acting on the FL piece 50 changes according to the magnitude of the rotational speed in the pull-out direction of the spool 18. Therefore, the sliding amount of the FL piece 50 can be changed in accordance with the rotational speed of the spool 18 in the pulling-out direction in a state where the blocking of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released. As a result, the amount of absorption of the tensile force applied to the webbing 20 from the body of the occupant due to the elastic deformation of the elastic piece 44 of the FL member 40 can be changed.

  For this reason, for example, in the case of a vehicle high-speed collision that is a collision in a state where the vehicle is traveling at a relatively high speed, the rotation speed in the pull-out direction of the spool 18 due to the webbing 20 being pulled by the body of the passenger is Relatively large. In such a case, in the present embodiment, the amount of sliding of the FL piece 50 toward the radially outer side of the FL base 46 increases. For this reason, in such a case, the pressing force required to elastically deform the elastic piece 44 of the FL member 40 increases, and as a result, the tensile force when the webbing 20 is pulled by the occupant's body is FL. A large amount can be absorbed by the elastic deformation of the elastic piece 44 of the member 40.

  On the other hand, in the case of a vehicle low-speed collision, which is a collision in a state where the vehicle is traveling at a relatively low speed, the rotational speed of the spool 18 in the pull-out direction due to the webbing 20 being pulled by the occupant's body. Relatively small. In such a case, in the present embodiment, the sliding amount of the FL piece 50 to the radially outer side of the FL base 46 becomes small. For this reason, in such a case, the pressing force required to elastically deform the elastic piece 44 of the FL member 40 is reduced. As a result, when the webbing 20 is pulled by the occupant's body, the occupant's body The reaction force received from the webbing 20 can be reduced.

  Further, in the present embodiment, the angle between the piece receiving grooves 48 of the FL base 46 adjacent around the central axis of the FL base 46 is set so that the elastic piece 44 adjacent around the center line of the ring portion 42 of the FL member 40 It is the same angle as the angle between. For this reason, the pressing portions 54 of the plurality of FL pieces 50 are brought into contact with the elastic pieces 44 of the FL member 40, and the timing at which the elastic pieces 44 of the FL member 40 are elastically deformed by the pressing portions 54 of the FL piece 50 is obtained. It will be almost the same. For this reason, the timing at which the elastic deformation amount of each elastic piece 44 of the FL member 40 is maximized by pressing each elastic piece 44 of the FL member 40 against the pressing portion 54 of the FL piece 50 is substantially the same.

  As described above, part of the tensile force applied to the webbing 20 from the occupant's body is absorbed by the elastic deformation of each elastic piece 44 of the FL member 40. In the present embodiment, each part of the FL member 40 is absorbed. Since the timing at which the elastic deformation amount of the elastic piece 44 becomes maximum is substantially the same, the maximum value of the absorption amount of the tensile force due to the elastic deformation of each elastic piece 44 of the FL member 40 can be increased.

  Furthermore, the relationship between the magnitude of the centrifugal force acting on the FL piece 50 and the sliding amount of the FL piece 50 is determined by the magnitude of the biasing force (spring constant) of the piece biasing spring 60. For this reason, by adjusting the urging force of the piece urging spring 60, the magnitude of the centrifugal force required to start the sliding of the FL piece 50 can be arbitrarily set.

  In the present embodiment, the spring constants of the piece biasing springs 60 provided in the piece biasing spring accommodating grooves 58 of the FL base 46 are set to be approximately the same size. However, for example, the spring constant may be different for each piece biasing spring 60.

  In such a configuration, even if the centrifugal force applied to each FL piece 50 has the same magnitude, the spring constant is different for each piece biasing spring 60, so that the FL base 50 has a radially outer side for each FL piece 50. Different slide amount. Thereby, for example, when the rotational speed of the FL base 46 in the pull-out direction is low, the number of FL pieces 50 with which the pressing portions 54 abut against the elastic pieces 44 of the FL member 40 can be reduced. As a result, when the rotational speed of the FL base 46 in the pull-out direction is low, that is, when the pull-out speed of the webbing 20 is low, all the elastic pieces 44 of the FL member 40 with which the pressing portion 54 of the FL piece 50 is in contact are removed. The rotational force in the pull-out direction of the FL base 46 required for elastic deformation can be reduced.

<Configuration of Second Embodiment>
Next, a second embodiment will be described.

  As shown in FIG. 8, in this embodiment, the contact piece 56 is not formed on the FL piece 50 of the second FL mechanism 38 of the force limiter. In the present embodiment, the piece biasing spring accommodating groove 58 is not formed in the FL base 46 of the second FL mechanism 38 of the force limiter. Therefore, in the present embodiment, the second FL mechanism 38 is provided with a piece. The spring 60 is not provided.

  On the other hand, in the present embodiment, a plate support portion 92 is formed on the front side surface of the FL base 46 of the second FL mechanism 38. An inertia plate 94 as an inertia mass body that constitutes a changing means together with the FL piece 50 is supported on the plate support portion 92 of the FL base 46 so as to be rotatable coaxially with the FL base 46. The inertia plate 94 is formed in a disc shape, and a plurality of guide holes 96 are formed in the inertia plate 94. These guide holes 96 have a long hole shape, and the number of guide holes 96 is the same as the number of FL pieces 50 of the second FL mechanism 38.

  These guide holes 96 contain guide pins 98 provided in the FL piece 50 of the second FL mechanism 38. The guide pin 98 is formed to project from the vehicle front side surface of the piece main body 52 of the FL piece 50 to the vehicle front side. When the FL base 46 is rotated relative to the inertia plate 94 in the pull-out direction, the FL piece 50 The guide pins 98 are guided in the guide holes 96 of the inertia plate 94, whereby the FL piece 50 is slid radially outward of the FL base 46.

  In the present embodiment, these guide holes 96 have the same shape although they are shifted by a certain angle around the central axis of the FL base 46. Therefore, the sliding amount of each FL piece 50 when the FL base 46 is rotated relative to the inertia plate 94 in the pull-out direction is the same size.

  In addition, an inertia contact portion 100 is formed on the inertia plate 94. The inertia contact portion 100 has a rectangular plate shape and extends from the inertia plate 94 to the vehicle rear side. Corresponding to the inertia contact portion 100, an inertia biasing spring accommodating groove 102 is formed in the FL base 46. The inertia urging spring accommodating groove 102 is opened at the vehicle front side of the FL base 46, and the inertia abutting portion 100 of the inertia plate 94 is in the inertia urging spring accommodating groove 102 of the FL base 46.

  An inertia biasing spring 104 is accommodated inside the inertia biasing spring accommodating groove 102. The inertia urging spring 104 is a compression coil spring, and one end of the inertia urging spring 104 is brought into contact with a side surface in the winding direction inside the inertia urging spring accommodating groove 102 of the FL base 46, and the inertia urging force is applied. The other end of the spring 104 is in contact with the inertia contact portion 100 of the inertia plate 94. Therefore, when the FL base 46 is rotated in the pull-out direction, the inertia contact portion 100 of the inertia plate 94 is pressed in the pull-out direction by the inertia biasing spring 104. As a result, the inertia plate 94 can rotate in the pull-out direction so as to follow the FL base 46.

  In the present embodiment, the number of elastic pieces 44 of the FL member 40 is set to be larger than the number of FL pieces 50. The number of elastic pieces 44 of the FL member 40 is different from a multiple of the number of FL pieces 50. In particular, in the present embodiment, the number of elastic pieces 44 of the FL member 40 is greater than the number of FL pieces 50. There is also one more. For this reason, the angle between the elastic pieces 44 of the FL members 40 adjacent to each other around the center line of the ring portion 42 of the FL member 40 is such that the FL piece receiving groove 48 of the FL base 46 adjacent to the FL base 46 around the center axis thereof. The angle between is smaller.

<Operation and Effect of Second Embodiment>
Next, the operation and effect of the present embodiment will be described.

  In the present embodiment, when the FL base 46 is rotated in the pull-out direction together with the spool 18 in a state where the FL piece 50 is prevented from sliding by the blocking piece 70 of the blocking member 62, the inertia contact portion 100 of the inertia plate 94 is rotated. Is pushed in the pull-out direction by the inertia biasing spring 104. As a result, the inertia plate 94 can rotate in the pull-out direction so as to follow the FL base 46.

  Here, for example, when the webbing 20 is pulled by the occupant's body and thereby the rotational acceleration in the pull-out direction of the FL base 46 exceeds a predetermined magnitude, the inertia plate 94 rotates to the FL base 46 due to inertia. There is a delay. As a result, when the FL base 46 is rotated in the pulling direction with respect to the inertia plate 94, the guide pin 98 of the FL piece 50 is guided to the guide hole 96 of the inertia plate 94, whereby the FL piece 50 is moved to the FL base. 46 is slid radially outward. Thus, the pressing portion 54 of the FL piece 50 is opposed to the elastic piece 44 of the FL member 40 and the circumferential direction of the FL base 46.

  When the FL base 46 is rotated in the pulling direction together with the spool 18 in this state, as shown in FIG. 9, the tip end portion (the pulling direction side end portion) of the pressing portion 54 of the FL piece 50 is moved to the FL member 40. As shown in FIG. 10, the elastic piece 44 of the FL member 40 rotates around the one end portion of the elastic piece 44 by the pressing force from the pressing portion 54 of the FL piece 50. It is elastically deformed. A rotational force in the pull-out direction of the spool 18, that is, a part of the tensile force applied to the webbing 20 from the occupant's body is subjected to elastic deformation of the elastic piece 44 of the FL member 40 and absorbed.

  Further, as the rotational acceleration of the FL base 46 in the pulling direction, that is, the pulling acceleration of the webbing 20 increases, the rotational delay of the inertia plate 94 with respect to the FL base 46 increases, and as shown in FIG. The sliding amount of the FL base 46 to the outside in the radial direction is increased. Therefore, when the rotational acceleration in the pull-out direction of the FL base 46 is large, the pressing portion 54 of the FL piece 50 approaches the ring portion 42 of the FL member 40, and the rotational acceleration in the pull-out direction of the FL base 46 is small ( The pressing portion 54 of the FL piece 50 is brought into contact with the elastic piece 44 on the one side end portion side of the elastic piece 44 of the FL member 40 (see FIG. 9). In this state, when the FL base 46 is further rotated in the pull-out direction, the blocking piece 70 of the blocking member 62 is elastically pressed by the pressing force from the pressing portion 54 of the FL piece 50 as shown in FIG. It is elastically deformed so as to turn around one side end.

  For this reason, when the FL base 46 is rotated in the pull-out direction together with the spool 18 in the release state where the FL piece 50 is blocked by the blocking piece 70 of the blocking member 62, the greater the rotational acceleration in the pull-out direction of the spool 18 is, The pressing force required to elastically deform the elastic piece 44 of the FL member 40 increases, and the amount of rotational force absorbed in the pull-out direction of the spool 18 by elastically deforming the elastic piece 44 of the FL member 40, that is, the occupant The amount of absorption of the tensile force applied to the webbing 20 from the body becomes larger.

  As a result, for example, the occupant's body size is large, and the rotational acceleration in the pull-out direction of the spool 18 due to the occupant's body pulling the webbing 20 in a state where the FL piece 50 is prevented from sliding by the blocking piece 70 of the blocking member 62. When it becomes larger, the tensile force applied to the webbing 20 from the occupant's body can be absorbed by the elastic piece 44 of the FL member 40 by elastic deformation.

  In the present embodiment, the magnitude of the rotational delay of the inertia plate 94 relative to the FL base 46 changes according to the magnitude of the rotational acceleration in the pull-out direction of the spool 18. For this reason, the sliding amount of the FL piece 50 can be changed in accordance with the magnitude of the rotational acceleration in the pull-out direction of the spool 18 in the state where the blocking of the FL piece 50 by the blocking piece 70 of the blocking member 62 is released. As a result, the amount of absorption of the tensile force applied to the webbing 20 from the body of the passenger due to the elastic deformation of the elastic piece 44 of the FL member 40 can be changed.

  For this reason, for example, in the case of a high-speed vehicle collision, the vehicle is rapidly decelerated due to the collision. For this reason, the webbing 20 is rapidly pulled by the occupant's body, thereby increasing the rotational acceleration of the spool 18 in the pull-out direction. In such a case, in the present embodiment, the amount of sliding of the FL piece 50 toward the radially outer side of the FL base 46 increases. For this reason, in such a case, the pressing force required to elastically deform the elastic piece 44 of the FL member 40 increases, and as a result, the tensile force when the webbing 20 is pulled by the occupant's body is FL. A large amount can be absorbed by the elastic deformation of the elastic piece 44 of the member 40.

  On the other hand, in the case of a vehicle low-speed collision, the rotational acceleration in the pull-out direction of the spool 18 due to the webbing 20 being pulled by the occupant's body is relatively small. In such a case, in the present embodiment, the sliding amount of the FL piece 50 to the radially outer side of the FL base 46 becomes small. For this reason, in such a case, the pressing force required to elastically deform the elastic piece 44 of the FL member 40 is reduced. As a result, when the webbing 20 is pulled by the occupant's body, the occupant's body The reaction force received from the webbing 20 can be reduced.

  The relationship between the magnitude of the rotational acceleration in the pulling direction of the FL base 46 and the magnitude of the rotational delay of the inertia plate 94 relative to the FL base 46 is related to the mass of the inertia plate 94 and the magnitude of the spring force of the inertia biasing spring 104. It depends on Sato. For this reason, by adjusting the mass of the inertia plate 94 and the magnitude of the spring force of the inertia biasing spring 104, the magnitude of the rotational acceleration in the pull-out direction of the spool 18 necessary for starting the slide of the FL piece 50 can be adjusted. Can be set arbitrarily.

  On the other hand, in the present embodiment, the angle between the elastic pieces 44 adjacent around the center line of the ring portion 42 of the FL member 40 is such that the FL piece receiving groove 48 of the FL base 46 adjacent to the FL base 46 around the central axis. The angle between is smaller. For this reason, as shown in FIGS. 9 and 11, the plurality of FL pieces 50 with the pressing portion 54 of the FL piece 50 </ b> A in contact with the elastic piece 44 of the FL member 40 among the plurality of FL pieces 50. 50, the pressing portion 54 of the FL piece 50 </ b> B adjacent to the FL piece 50 </ b> A on the winding direction side is not in contact with the elastic piece 44 of the FL member 40.

  From this state, the angle between the FL piece receiving grooves 48 of the FL base 46 adjacent around the center axis of the FL base 46 and the angle between the elastic pieces 44 adjacent around the center line of the ring portion 42 of the FL member 40. When the FL base 46 is rotated in the pull-out direction by the difference between the elastic piece 44 and the elastic piece 44 of the FL member 40 by the pressing portion 54 of the FL piece 50A, as shown in FIGS. The elastic piece 44 of the FL member 40 pressed by the pressing portion 54 is elastically deformed. Further, in this state, the pressing portion 54 of the FL piece 50B is brought into contact with the elastic piece 44 of the FL member 40, and the FL base 46 is further rotated in the pulling direction from this state, whereby the pressing portion 54 of the FL piece 50B. Thus, the elastic piece 44 of the FL member 40 is pressed and elastically deformed.

  As described above, in the present embodiment, the elastic deformation of all the elastic pieces 44 of the FL member 40 is not started at the same time. Phase difference). For this reason, the timing at which the absorption amount of the tensile force when the webbing 20 due to the elastic deformation of each elastic piece 44 of the FL member 40 is pulled by the body of the occupant is maximized can be shifted. As a result, it is possible to suppress an increase in the difference between the maximum value and the minimum value of the overall absorption amount of the tensile force when the FL base 46 is rotated together with the spool 18 in the pull-out direction.

  In the present embodiment, the angle between the elastic pieces 44 adjacent around the center line of the ring portion 42 of the FL member 40 is set to the FL piece receiving groove 48 of the FL base 46 adjacent around the center axis of the FL base 46. However, the angle between the elastic pieces 44 adjacent to each other around the center line of the ring portion 42 of the FL member 40 is set to the FL base as in the first embodiment. The angle between the FL piece receiving grooves 48 of the adjacent FL bases 46 around the central axis 46 may be the same.

  In the present embodiment, the angle between the elastic pieces 44 adjacent to each other around the center line of the ring portion 42 of the FL member 40 is set to the FL piece receiving groove 48 of the FL base 46 adjacent to the center axis of the FL base 46. However, the configuration may be applied to the first embodiment.

  Furthermore, in the present embodiment, when the FL base 46 is rotated relative to the inertia plate 94 in the pull-out direction, the sliding amount of each FL piece 50 to the radially outer side of the FL base 46 is substantially the same size. Was set to be. However, the sliding amount of each FL piece 50 toward the outer side in the radial direction of the FL base 46 when the FL base 46 is rotated relative to the inertia plate 94 in the pull-out direction may be varied.

  For example, when the rotational acceleration in the pull-out direction of the FL base 46 is small, the pressing portion 54 of a part of the FL pieces 50 among the plurality of FL pieces 50 is configured to contact the elastic piece 44 of the FL member 40. The rotational force in the pull-out direction of the FL base 46 required for elastically deforming all the elastic pieces 44 of the FL member 40 against which the pressing portion 54 of the FL piece 50 abuts can be reduced.

  Further, in each of the above embodiments, the elastic piece 44 of the FL member 40 has a configuration in which the thickness dimension is substantially equal from the one side end portion on the ring portion 42 side to the other side end portion on the opposite side. there were. However, a configuration in which the thickness dimension of the elastic piece 44 is changed between the one side end portion and the other side end portion, such as reducing (thinning) the thickness dimension of the other side with respect to one side of the elastic piece 44. It is good. For example, in the configuration in which the thickness dimension on the other side is smaller than one side of the elastic piece 44, the rigidity against the pressing force from the pressing portion 54 of the FL piece 50 is lower on the other side than the one side of the elastic piece 44. For this reason, the pressing force required to elastically deform the elastic piece 44 can be reduced on the other side of the elastic piece 44.

  Further, in each of the above-described embodiments, the FL base 46 of the second FL mechanism 38 is configured such that relative rotation with respect to the spool 18 is prevented and always rotates together with the spool 18. However, a clutch may be interposed between the FL base 46 and the spool 18 so that the FL base 46 is connected to the spool 18 by the clutch in the event of a vehicle emergency, whereby the FL base 46 is rotated together with the spool 18. In such a configuration, the FL base 46 is not rotated even when the spool 18 is rotated in a normal state (a state before the vehicle emergency occurs). For this reason, the FL piece 50 provided on the FL base 46 is not slid radially outward of the FL base 46 due to the rotation of the spool 18 in a normal state.

  Accordingly, in such a configuration, it is not necessary to provide the blocking member 62. Further, in such a configuration, the pressing portion 54 of the FL piece 50 can be previously opposed to the elastic piece 44 of the FL member 40 in the circumferential direction of the FL base 46, and furthermore, along the circumferential direction of the FL base 46. The distance between the pressing portion 54 of the FL piece 50 and the elastic piece 44 of the FL member 40 can be arbitrarily set. As a result, the rotation angle of the FL base 46 in the pulling direction required from when the FL base 46 starts to rotate in the pulling direction until the pressing portion 54 of the FL piece 50 contacts the elastic piece 44 of the FL member 40 can be arbitrarily set. Can be set.

  Further, in each of the above-described embodiments, the elastic piece 44 of the FL member 40 is configured to be formed around the center of the ring portion 42 of the FL member 40 at a constant angle. However, the angle between the elastic pieces 44 of the adjacent FL members 40 around the center of the ring portion 42 of the FL member 40 may be changed for each elastic piece 44. Further, in each of the above-described embodiments, the piece urging spring accommodating groove 58 of the FL base 46 is configured to be formed around the central axis of the FL base 46 at a predetermined angle. However, the angle between the piece biasing spring accommodating grooves 58 of the FL base 46 adjacent to the periphery of the central axis of the FL base 46 may be changed for each piece biasing spring accommodating groove 58.

  The angle between the elastic pieces 44 of the adjacent FL members 40 around the center of the FL member 40 is changed for each elastic piece 44, or the piece biasing spring accommodating groove 58 of the FL base 46 adjacent around the central axis of the FL base 46. Is changed for each piece biasing spring accommodating groove 58, for example, immediately after the operation of the second force limiter mechanism 38 starts, the elastic pieces 44 of the FL member 40 are elastically deformed into many elastic pieces 44. It becomes possible to make it the structure which produces.

  Further, the first embodiment has a configuration in which the sliding amount of the FL piece 50 to the radially outer side of the FL base 46 changes in accordance with the rotational speed of the FL base 46 in the pull-out direction. In contrast, the second embodiment has a configuration in which the sliding amount of the FL piece 50 to the radially outer side of the FL base 46 changes in accordance with the magnitude of the rotational acceleration in the pull-out direction of the FL base 46. It was. However, a configuration in which the sliding amount of the FL base 50 in the radially outward direction of the FL base 50 changes according to the magnitude of the rotational speed of the FL base 46 in the pull-out direction, and the rotational acceleration of the FL base 46 in the pull-out direction. You may combine with the structure from which the sliding amount to the radial direction outer side of FL base 46 of FL piece 50 changes according to a magnitude | size.

  Furthermore, in each of the above embodiments, the elastic piece 44 of the FL member 40 is elastically deformed by the pressing force from the pressing portion 54 of the FL piece 50. However, a configuration in which a part of the FL member 40 is plastically deformed (including fracture) by the pressing force from the pressing portion 54 of the FL piece 50 may be used.

  Each of the above embodiments has a configuration in which the FL piece 50 having the pressing portion 54 is provided in the FL base 46 as the rotating member, and the elastic piece 44 as the deforming portion is provided in the FL member 40 as the fixing member. It was. However, the pressing member is provided on the fixed member, and the deforming portion is provided on the rotating member so as to be movable according to the rotational speed or the acceleration of the rotating member. It is good also as a structure from which the distance of the position pressed by a press part in an edge part and a deformation | transformation part changes.

10 Webbing take-up device 12 Frame (support member)
18 Spool 20 Webbing 40 Force limiter member (fixing member)
44 Elastic piece (deformation part)
46 Force limiter base (Rotating member)
50 Force limiter piece (change means)
60 piece bias spring (change means)
94 Inertia plate (change means)

Claims (4)

A spool that is rotated in the pull-out direction when the webbing is pulled toward the longitudinal tip side;
A support member for supporting the spool;
A rotating member rotated by rotation of the spool;
A fixing member supported by the support member on the radial direction side of the rotating member;
One end of the rotating member and the fixed member is connected to one end, the other side extends to the other side of the rotating member and the fixed member, and deformation is caused by applying a force along the circumferential direction of the rotating member. And a deformed portion that reduces the force required for the deformation by changing the force application position to the other side rather than the one side end,
A pressing portion that is provided on the other of the rotating member and the fixing member and is capable of pressing the deforming portion by rotation of the rotating member;
Changing means for changing the distance between the pressing position of the deforming portion and the one side end of the deforming portion in the pressing portion according to at least one of the rotational speed of the rotating member and the rotational acceleration of the rotating member; ,
A webbing take-up device comprising:   The webbing take-up device according to claim 1, wherein the deformation of the deformation portion caused by being pressed by the pressing portion is elastic deformation.   The webbing retractor according to claim 1 or 2, wherein a plurality of at least one of the pressing portion and the deforming portion is provided.   The plurality of pressing portions are provided at predetermined angles around the central axis of the rotating member, and the plurality of deforming portions are provided around the central axis of the rotating member at different angles from the predetermined angle. The webbing take-up device according to any one of claims 1 to 3.