JP2015199416A - webbing take-up device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a webbing take-up device capable of improving resistance to a load from a base end of webbing in a spool.SOLUTION: In a webbing take-up device, one end of a spool 18 is fitted with a support member 76 higher in strength than the spool 18. One width-direction end of a loop part 26 of webbing 24 abuts on both support surfaces 90 inside a support part 88 of the support member 76, and a load acts on both the support surfaces 90 when the webbing 24 is pulled to a tip end side.

Description

  The present invention relates to a webbing take-up device in which a base end portion of a webbing is locked to a spool by the webbing being disposed through the insertion hole of the spool.

  There is a webbing take-up device in which an insertion hole is formed through the spool in a direction perpendicular to the spool axis, and the webbing is disposed through the insertion hole (see Patent Document 1 below as an example). In this type of webbing take-up device, a loop portion is formed at the base end portion of the webbing, and a cylindrical webbing stopper is disposed inside the loop portion. Thus, the loop portion (base end portion) of the webbing cannot pass from one side of the insertion hole of the spool to the other side, and the webbing is locked to the spool.

  Here, when the webbing is pulled toward the front end side, a load that opens the insertion hole is applied to the vicinity of one end of the insertion hole in the spool from the loop portion of the webbing. For this reason, it is necessary to consider such a load.

JP-A-11-157416

  In view of the above fact, an object of the present invention is to obtain a webbing take-up device that can improve load resistance from a base end portion of a webbing in a spool.

  The webbing take-up device according to claim 1, wherein a webbing provided with a retaining member at a base end portion and an insertion hole through which the webbing can pass are formed, and the webbing is formed on one side of the insertion hole by the retaining member. A spool to which the base end portion of the webbing is locked, and a width direction end portion of the base end portion of the webbing when the webbing is pulled by being provided on the spool and having a mechanical strength higher than that of the spool. And a support member to which a tensile load of the webbing is applied.

  In the webbing take-up device according to the first aspect, when the webbing is pulled, a tensile load of the webbing is applied to the support member provided on the spool from the base end portion of the webbing. Here, the mechanical strength of the support member is set higher than that of the spool. For this reason, the load tolerance from the base end part of the webbing in a spool can be improved.

  The webbing take-up device according to claim 2 is the webbing take-up device according to claim 1, wherein the support member has an insertion portion through which the webbing penetrates and an inner width of the insertion portion is partially It has a pair of support surfaces which are formed by enlarging and contact the base end portion of the webbing.

  In the webbing take-up device according to claim 2, the base end portion of the webbing is brought into contact with a pair of support surfaces formed by partially expanding the inner width of the insertion portion of the support member. Loads from the ends can be received by these support surfaces.

  The webbing take-up device according to a third aspect is the webbing take-up device according to the second aspect, wherein the insertion portion is an insertion groove opened toward the center side in the spool axial direction, and the support member is It is continuous in the spool circumferential direction outside the insertion groove in the spool axial direction.

  In the webbing take-up device according to claim 3, when a load from the base end portion of the webbing acts on the pair of support surfaces, it is possible to effectively suppress deformation of the support member such that the pair of support surfaces separate from each other. .

  The webbing take-up device according to claim 4 is the webbing take-up device according to claim 2 or 3, wherein the strength of the support surface portion of the support member is set higher than other portions of the support member. Has been.

  In the webbing take-up device according to the fourth aspect, when the load from the base end portion of the webbing acts on the support surface, the deformation of the support surface portion in the support member can be effectively suppressed.

  The webbing take-up device according to a fifth aspect is the webbing take-up device according to the fourth aspect, wherein a convex portion is formed to protrude radially outward from the support member, and the support surface portion is set to the convex portion. ing.

  According to the webbing take-up device of the fifth aspect, the strength of the support surface portion of the support member can be increased as compared with the case where the support surface portion is set at a site different from the convex portion.

  The webbing take-up device according to claim 6 is the webbing take-up device according to any one of claims 1 to 5, wherein the support member is attached to one end of the spool in the axial direction. .

  In the webbing take-up device according to the sixth aspect, since the support member is attached to one end of the spool in the axial direction, the support member can be assembled to the spool in the spool axial direction.

  A webbing take-up device according to a seventh aspect of the present invention is the webbing take-up device according to any one of the first to sixth aspects, wherein the webbing take-up device is provided so as to be rotatable integrally with the spool and moves in a pull-out direction in the event of a vehicle emergency. A lock base that is limited in rotation, an energy absorbing member that is deformed by rotating the spool in the pull-out direction with respect to the lock base in an emergency of the vehicle, and absorbs the rotational force of the spool, and the spool On the other hand, when the spool is engaged with the support member provided so as not to rotate relative to the lock base a predetermined number of times and the spool rotates in the pull-out direction with respect to the lock base, the spool moves in the pull-out direction. A rotation preventing member that prevents rotation.

  According to the webbing take-up device of the seventh aspect, since the mechanical strength of the support member is higher than that of the spool, the rotation force received by the support member from the rotation prevention member in the rotation prevention state of the spool in the pulling-out direction. High strength can be secured.

  The webbing take-up device according to claim 8 is the webbing take-up device according to claim 7, wherein a rotational force can be transmitted between the support member and the spool, and the support member with respect to the spool. A plurality of stop portions for preventing relative rotation are provided.

  In the webbing take-up device according to the eighth aspect, when the rotational force is transmitted between the support member and the spool, the rotational force is distributed to the plurality of rotation stop portions. Thereby, the stress concentration when the rotational force is transmitted between the support member and the spool can be suppressed.

  As described above, in the webbing take-up device according to the present invention, it is possible to improve load resistance from the base end portion of the webbing in the spool.

It is a disassembled perspective view from the rear right side of the webbing take-up device according to the first embodiment. It is a disassembled perspective view from the rear left side of a spool and a supporting member. FIG. 3 is a cross-sectional view of the spool and a member to be assembled thereto in an assembled state, in which (A) is a cross-sectional view taken along line 3A-3A in FIG. It is. It is a disassembled perspective view of the spool of the webbing retractor which concerns on 2nd Embodiment, and the member assembled | attached to this. FIGS. 5A and 5B are cross-sectional views of the spool, lock base, support member, and stopper taken along line 5-5 in FIG. 4, where FIG. 5A shows an initial state of the stopper, and FIG.

  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 webbing retractor 10, 110, the arrow LH indicates the left side, and the arrow UP indicates the upper side.

<Configuration of First Embodiment>
As shown in FIG. 1, the webbing retractor 10 according to the present embodiment includes a frame 12 that is fixed to a vehicle frame member or a reinforcing member on the rear side of the rear seat. The frame 12 includes wall portions 14 and 16 that face in the left-right direction, and a spool 18 is provided between the wall portion 14 and the wall portion 16. The axial direction of the spool 18 is along the left-right direction, and a through hole 20 is formed in the spool 18 along the central axis.

  As shown in FIGS. 2 and 3A, an insertion hole 22 is formed in the spool 18. As shown in FIG. 3A, the insertion hole 22 is in a direction parallel to the direction orthogonal to the spool 18 axis (the direction of arrow A in FIG. 3A) at a position shifted in the radial direction from the center axis of the spool 18. It passes through the spool 18 and is connected to the through hole 20 at the intermediate portion. A webbing 24 is inserted from one side of the insertion hole 22. An annular loop portion 26 is formed at the base end portion of the webbing 24, and a cylindrical webbing stopper 28 as a retaining member is disposed inside the loop portion 26.

  As shown in FIG. 3A, the outer shape of the loop portion 26 in a state in which the webbing stopper 28 is provided is larger than the inner width of the insertion hole 22 when viewed in the axial direction of the spool 18, thereby 26 cannot pass through the insertion hole 22. One end portion of the insertion hole 22 where the loop portion 26 is located is a housing portion 30 that is widened when viewed in the axial direction of the spool 18, and the loop portion 26 is disposed in the housing portion 30.

  In this way, the base end of the webbing 24 is locked to the spool 18, and the webbing 24 is wound around the outer periphery of the spool 18 in a layered manner by rotating the spool 18 around the axis in the winding direction. It is done. As shown in FIGS. 1 and 2, flanges 32 are formed at both axial end portions of the spool 18, and in these flange portions 32, the spool 18 radial dimension is the center of the spool 18 in the axial direction. Bigger than the side. Further, as shown in FIG. 1, a rotating member 34 is provided on the left side of the spool 18. The rotating member 34 is fitted into the through hole 20 from the left side of the spool 18, thereby preventing relative rotation of the rotating member 34 with respect to the spool 18.

  On the left side of the frame 12, a pretensioner 36 that is activated in the event of a vehicle emergency such as a vehicle collision is provided. When the pretensioner 36 is operated, the rotating member 34 is rotated in the winding direction. As a result, the spool 18 is rotated in the winding direction, and the webbing 24 is wound around the spool 18. A spring housing 38 is provided on the left side of the pretensioner 36, and the rotating member 34 is rotatably supported by the spring housing 38. A spiral spring (not shown) is provided in the spring housing 38. The spiral spring is engaged with the rotating member 34, and thereby the spool 18 is biased in the winding direction.

  On the other hand, a torsion shaft 40 as an energy absorbing member is provided inside the through hole 20 of the spool 18. The torsion shaft 40 includes a shaft portion 42, and a connecting portion 44 is formed on the left side of the shaft portion 42. A connecting portion 46 is formed on the right side of the shaft portion 42, and a support shaft 48 is formed on the right side of the connecting portion 46 so as to protrude coaxially with the spool 18. The connecting portion 44 on the left side of the torsion shaft 40 is engaged with the spool 18 inside the through hole 20 of the spool 18, thereby preventing relative rotation of the torsion shaft 40 with respect to the spool 18.

  A lock base 50 is provided on the right side of the spool 18. The left end surface of the lock base 50 is in contact with the right end surface of the spool 18, and the lock base 50 is engaged with the right connecting portion 46 of the torsion shaft 40 so that the relative rotation with respect to the torsion shaft 40 is performed. It is blocked. As a result, the lock base 50 can rotate integrally with the spool 18. However, when the rotation force exceeding the mechanical strength of the torsion shaft 40 acts on the spool 18 in a state where the rotation of the lock base 50 is prevented, the spool 18 is rotated while the shaft portion 42 of the torsion shaft 40 is twisted and deformed. .

  Further, a lock pawl 52 is rotatably supported on the lock base 50. The lock pawl 52 is arranged inside a ratchet hole 54 formed in the right wall 16 of the frame 12, and meshes with the ratchet teeth of the ratchet hole 54 by rotating. As a result, the lock base 50 is prevented from rotating in the pull-out direction opposite to the winding direction. A sensor mechanism 56 is provided on the right side of the lock base 50. The sensor mechanism 56 includes a V gear 58. The V gear 58 has ratchet teeth formed on the outer periphery thereof, and is rotatably supported on the support shaft 48 of the torsion shaft 40. Further, an engagement shaft 60 formed on the lock pawl 52 is engaged with the V gear 58, and the lock pawl 52 rotates when the lock base 50 is rotated relative to the V gear 58 in the pull-out direction. Then, it meshes with the ratchet teeth of the ratchet hole 54.

  A spring (not shown) is provided between the lock base 50 and the V gear 58. When the spring is rotated in the pull-out direction together with the lock base 50, the V gear 58 is pressed in the pull-out direction by the spring. . As a result, the V gear 58 follows the lock base 50 and rotates in the pull-out direction. However, when the lock base 50 rotates in the pull-out direction, the spring is elastically deformed, so that the lock base 50 can rotate relative to the V gear 58 in the pull-out direction.

  On the other hand, the sensor mechanism 56 includes a first cover 62, and the V gear 58 is accommodated in the first cover 62. Inside the first cover 62, internal ratchet teeth are formed coaxially with the support shaft 48 of the torsion shaft 40. Corresponding to the ratchet teeth, a W pawl 64 constituting a WSIR mechanism is supported on the V gear 58 so as to be swingable. The WSIR mechanism is operated when the spool 18 is rotated in the pull-out direction at a rotational acceleration of a predetermined magnitude or more in a vehicle emergency such as a vehicle collision. When the V gear 58 together with the spool 18 is rotated in the pull-out direction with a rotational acceleration of a predetermined magnitude or more, the W pawl 64 is swung and engaged with the ratchet teeth of the first cover 62. As a result, rotation of the V gear 58 in the pull-out direction is prevented.

  A second cover 66 is provided on the right side of the first cover 62, and the first cover 62 is accommodated inside the second cover 66. The front end side of the support shaft 48 of the torsion shaft 40 passes through the first cover 62 and is rotatably supported by the second cover 66. The second cover 66 is provided with an acceleration sensor 68 constituting a VSIR mechanism, and the VSIR mechanism is operated in a vehicle rapid deceleration state such as when a vehicle collides. The acceleration sensor 68 includes a hard ball 70 that rolls by inertia when the vehicle collides. When the hard ball 70 rolls, the sensor pawl 72 of the acceleration sensor 68 is pushed up by the hard ball 70 and meshes with the ratchet teeth of the V gear 58. As a result, rotation of the V gear 58 in the pull-out direction is prevented.

  As shown in FIGS. 1 and 2, one end portion (right end portion) of the through hole 20 formed in the spool 18 is enlarged in diameter to form a fitting portion 74, and the fitting portion 74 is formed by the webbing 24. It is connected to one end of the insertion hole 22 to be inserted. A support member 76 is fitted to the fitting portion 74. The support member 76 is generally formed of a metal material that has higher mechanical strength than the spool 18, in particular, at least one of compressive strength and shear strength. The support member 76 is formed in a ring shape, and the inner peripheral shape of the support member 76 is a circle coaxial with the spool 18. As shown in FIGS. 1 and 2, a bottom portion 78 is formed at the other end (left end portion) of the support member 76 in the axial direction of the spool 18. A circular hole 80 is formed on the center side in the radial direction of the bottom 78, and the torsion shaft 40 passes through the circular hole 80.

  A plurality of convex portions 82 are formed as protrusions on the outer peripheral portion of the support member 76, and the outer diameter of the support member 76 is different from the convex portion 82 of the support member 76. Longer than. Corresponding to these convex portions 82, the fitting portion 74 includes a plurality of concave portions 84 as rotation preventing portions, and when the support member 76 is fitted into the fitting portion 74, each convex portion 82 becomes each concave portion. 84, thereby preventing the support member 76 from rotating relative to the spool 18.

  As shown in FIG. 2, an insertion groove 86 is formed in the bottom portion 78 of the support member 76 as an insertion portion that opens toward the other side (left side) in the axial direction of the spool 18. As shown in FIG. 3B, the insertion groove 86 is parallel to the direction orthogonal to the support member 76 axis (the direction of the arrow B in FIG. 3B) at a position shifted in the radial direction from the central axis of the support member 76. It penetrates the support member 76 in the direction and is connected to the circular hole 80 at the intermediate portion. With the support member 76 fitted in the fitting portion 74, the insertion groove 86 faces the insertion hole 22 of the spool 18 in the axial direction of the spool 18, and one end in the width direction of the webbing 24 that passes through the insertion hole 22 (on the right side) End) penetrates the insertion groove 86.

  One end portion of the insertion groove 86 is a support portion 88 as a support surface portion widened in the axial direction of the spool 18, and one end portion in the webbing 24 width direction of the loop portion 26 provided with the webbing stopper 28 is supported. Arranged in the portion 88. Both sides of the support portion 88 through the insertion groove 86 are support surfaces 90, and the loop portion 26 disposed in the support portion 88 is brought into contact therewith. Further, the support portion 88 is formed at one formation position of the plurality of convex portions 82 in the support member 76, and the support portion 88 partially overlaps one convex portion 82 in the axial direction of the support member 76. ing. For this reason, the setting part of the support surface 90 in the support member 76 has a longer dimension in the radial direction of the spool 18 than a part different from the setting part of the support surface 90 in the support member 76.

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

  In the webbing take-up device 10, in the event of a vehicle emergency such as a vehicle collision, the webbing 24 attached to the occupant's body is pulled, and the lock base 50 together with the spool 18 moves in the pull-out direction with a rotational acceleration greater than a predetermined size. When rotated, the WSIR mechanism of the sensor mechanism 56 is activated. Further, the VSIR mechanism of the sensor mechanism 56 is operated in the sudden deceleration state of the vehicle due to the vehicle collision. As described above, the WS gear mechanism and the VSIR mechanism are actuated to prevent the V gear 58 from rotating in the pull-out direction.

  In this state, when the lock base 50 is rotated in the pull-out direction together with the spool 18, and the lock base 50 is rotated relative to the V gear 58 in the pull-out direction, the lock pawl 52 provided on the lock base 50 is It is rotated. Accordingly, when the teeth of the lock pawl 52 are engaged with the inner teeth of the ratchet hole 54 of the right wall portion 16, the lock base 50 is prevented from rotating in the pull-out direction, and the spool 18 is rotated in the pull-out direction. Is blocked. This prevents the webbing 24 from being pulled out of the spool 18.

  In this state, when the rotational force in the pull-out direction of the spool 18 exceeds the mechanical strength of the shaft portion 42 of the torsion shaft 40, the spool 18 is rotated in the pull-out direction while the shaft portion 42 is twisted. The webbing 24 is pulled out of the spool 18 by the amount of rotation of the spool 18 and part of the energy of the rotational force of the spool 18 is subjected to torsional deformation of the torsion shaft 40 and absorbed.

  On the other hand, the webbing 24 is pulled in the direction of the arrow F (the tip side) in a state where the sensor mechanism 56 is actuated to prevent the spool 18 from rotating in the pull-out direction, or in the full-drawn state where all the webbing 24 is pulled out from the spool 18. Then, as shown in FIG. 3A, loads F <b> 1 and F <b> 2 that are intended to expand the insertion hole 22 from the loop part 26 (base end part) of the webbing 24 are applied to the accommodation part 30 of the insertion hole 22. . On the other hand, as shown in FIG. 3B, at one axial end portion of the spool 18, the loop portion 26 of the webbing 24 is inserted inside the support portion 88 of the support member 76 provided on the spool 18. Thus, the loads F <b> 1 and F <b> 2 from the loop portion 26 can be supported by both support surfaces 90 of the support portion 88.

  Here, the compressive strength of the support member 76 is set higher than the compressive strength of the spool 18. Therefore, when the loads F1 and F2 from the loop portion 26 act on the support surface 90 of the support portion 88, the support portion 88 is difficult to compress and deform, and the deformation in which the interval between the both support surfaces 90 increases is not likely to occur. For this reason, by providing the support member 76 on the spool 18, high load resistance can be obtained with respect to the loads F1 and F2 from the webbing 24.

  Moreover, the support portion 88 of the support member 76 is formed at the position where the convex portion 82 is formed, and the support portion 88 partially overlaps the single convex portion 82 in the axial direction of the support member 76. The convex portion 82 of the support member 76 has a longer radial dimension than the portion of the support member 76 that is different from the convex portion 82, and the support surface 90 is set on the convex portion 82. 88 can be increased. As a result, the compressive strength against the loads F1 and F2 from the webbing 24 is higher than that of a portion different from the portion where the convex portion 82 is formed in the support member 76. Accordingly, it is possible to ensure high strength against the loads F1 and F2 from the webbing 24 without increasing the size of the support member 76 itself.

  Further, on the one axial side (right side) of the spool 18 with respect to the insertion groove 86 of the support member 76, the support member 76 is annularly continued. For this reason, even if a load that causes the two support surfaces 90 to be separated from each other acts on the support member 76, the support portion 88 can be supported by the annular portion of the support member 76 on one side in the axial direction of the spool 18 relative to the both support surfaces 90. . In addition, when a load that causes the two support surfaces 90 to be separated from each other acts on both the support surfaces 90, a shear stress acts between the support portion 88 of the support member 76 and the annular portion of the support member 76. Here, since the support member 76 has higher strength against the shear load than the spool 18, deformation or the like hardly occurs between the support portion 88 of the support member 76 and the annular portion of the support member 76. From the above, load resistance can be obtained with respect to the loads F1 and F2 from the webbing 24.

  Further, the fitting portion 74 into which the support member 76 is fitted is formed at one end of the spool 18 in the axial direction. For this reason, the support member 76 can be easily assembled in the axial direction of the spool 18. Moreover, since the flange portion 32 is formed at one end of the spool 18 in the axial direction, the dimension in the radial direction of the spool 18 is longer than that at the axial center side of the spool 18. For this reason, even if the fitting part 74 is formed in the spool 18, the fall of the mechanical strength in the axial direction one end part of the spool 18 can be suppressed.

  In the present embodiment, the support member 76 is provided at one end of the spool 18 in the axial direction. However, a support member in which the structure of the support member 76 is reversed left and right is provided at the other end of the spool 18 in the axial direction. Alternatively, support members 76 may be provided at both axial ends of the spool 18. Furthermore, the support member can receive a load from the proximal end portion of the webbing, and the mechanical strength with respect to such a load should be higher than that of the spool, and the mounting position of the support member on the spool is particularly limited. It is not something.

<Configuration of Second Embodiment>
In describing the second embodiment of the present invention, components that are basically the same as those of the first embodiment are given the same reference numerals, and detailed descriptions thereof are omitted.

  As shown in FIG. 4, in the webbing take-up device 110 according to the present embodiment, a housing portion 112 is formed in the support member 76. The accommodating portion 112 is formed by expanding a part of the inside of the support member 76 on one side (right side) in the axial direction from the bottom portion 78 of the support member 76. The accommodating portion 112 is formed on the side opposite to the supporting portion 88 when the supporting member 76 is viewed in the axial direction. An FL stopper 114 as a rotation preventing member is accommodated inside the accommodating portion 112.

  The FL stopper 114 is curved in a substantially C shape around the support member 76 axis. The circumferential end surfaces 114A and 114B of the FL stopper 114 are opposed to the circumferential end surfaces 112A and 112B of the accommodating portion 112, thereby restricting relative rotation of the FL stopper 114 with respect to the support member 76. Further, the thickness dimension of the FL stopper 114 (dimension in the axial direction of the support member 76) is smaller than the depth dimension (dimension in the axial direction of the support member 76) of the accommodating portion 112, whereby the FL stopper 114 is located inside the accommodating portion 112. Thus, the support member 76 can be moved in the axial direction.

  In the present embodiment, a cylindrical portion 116 is formed on the spool 18 side surface (left side surface) of the lock base 50. The cylindrical portion 116 is formed coaxially with the spool 18. The inner peripheral shape of the cylindrical portion 116 is a similar shape slightly larger than the outer peripheral shape of the connecting portion 46 on the right side of the torsion shaft 40. By fitting the connecting portion 46 of the torsion shaft 40 inside the cylindrical portion 116, the lock base 50 is prevented from rotating relative to the torsion shaft 40.

  A male screw 118 is formed on the outer peripheral portion of the cylindrical portion 116, and a female screw 120 is formed on the radially inner side surface of the FL stopper 114 corresponding to the male screw 118. As shown in FIG. 5A, the FL stopper 114 is arranged on the bottom 78 side of the support member 76 in the initial state, and in this state, the female screw 120 of the FL stopper 114 is the male screw of the cylindrical portion 116 of the lock base 50. 118 is screwed together. When the FL stopper 114 is rotated around the cylindrical portion 116 in the pull-out direction, the female screw 120 of the FL stopper 114 is guided by the male screw 118 of the cylindrical portion 116 toward the lock base 50 as shown in FIG. Moved.

<Operation and Effect of Second Embodiment>
When the spool 18 is rotated in the pull-out direction, the surface on the winding direction side of the convex portion 82 of the support member 76 is pressed by the surface on the winding direction side of the concave portion 84 of the fitting portion 74 of the spool 18. As a result, the support member 76 is rotated in the pull-out direction integrally with the spool 18. When the support member 76 is rotated in the pull-out direction, the end surface 114A on the winding direction side of the FL stopper 114 is pressed against the end surface 112A on the winding direction side of the housing portion 112. As a result, the FL stopper 114 is rotated in the pull-out direction integrally with the support member 76.

  When the spool 18 is rotated relative to the lock base 50 in the pull-out direction in a state where the sensor mechanism 56 is activated and the lock base 50 is prevented from rotating in the pull-out direction, the FL stopper 114 moves in the pull-out direction together with the spool 18. It is rotated. As a result, the female screw 120 of the FL stopper 114 is guided by the male screw 118 of the cylindrical portion 116 of the lock base 50 and the FL stopper 114 is moved to the lock base 50 side.

  When the spool 18 is rotated a certain number of times in the pull-out direction, the surface of the FL stopper 114 on the lock base 50 side is brought into contact with the surface of the lock base 50 on the spool 18 side, as shown in FIG. In this state, since the FL stopper 114 cannot move to the lock base 50 side, the rotation of the FL stopper 114 around the cylindrical portion 116 is prevented. By preventing the FL stopper 114 from rotating in the pull-out direction, the support member 76 is prevented from rotating in the pull-out direction, and further, the spool 18 is prevented from rotating in the pull-out direction. Thereby, the drawing of the webbing 24 from the spool 18 and the torsional deformation of the shaft portion 42 of the torsion shaft 40 are completed.

  By the way, when the pulling direction rotational force is applied to the spool 18 in a state where the movement of the FL stopper 114 is blocked, the female screw 120 of the FL stopper 114 is connected to the cylindrical portion of the lock base 50 at both circumferential ends of the FL stopper 114. An attempt is made to deform outward in the radial direction by the axial force received from the male screw 118. Here, in the present embodiment, such deformation of the FL stopper 114 is suppressed by the support member 76 having a higher compressive strength than the spool 18. For this reason, the screwed state of the male screw 118 of the lock base 50 and the female screw 120 of the FL stopper 114 can be maintained.

  Further, since the deformation of the FL stopper 114 is suppressed by the support member 76 having a compressive strength higher than that of the spool 18, a configuration for accommodating the FL stopper 114 is provided on one side of the spool 18. Increase in size can be suppressed. As a result, the radial dimension of the spool 18 can be reduced, the axial dimension of the spool 18 can be reduced by making the flange portion 32 thinner, and the mechanical strength of the spool 18 itself can be reduced. Therefore, the weight of the spool 18 can be reduced.

  Further, the rotational force is transmitted from the spool 18 to the support member 76 between the plurality of concave portions 84 and the plurality of convex portions 82, and the rotational force is distributed to the concave portions 84 and the convex portions 82. For this reason, the stress does not concentrate on specific portions of the spool 18 and the support member 76 during the transmission of the rotational force. Therefore, the rotational force can be transmitted between the spool 18 and the support member 76 without setting the mechanical strength of the support member 76 or the mechanical strength of the spool 18 in the vicinity of the fitting portion 74 to be particularly high. Also by this, the mechanical strength of the spool 18 itself can be reduced, and the weight of the spool 18 can be reduced.

  In the present embodiment, the FL stopper 114 serving as a rotation prevention member is disposed on the bottom 78 side of the support member 76 in the initial state, and the spool 18 rotates in the pull-out direction with respect to the lock base 50, thereby causing the FL stopper. 114 was moved to the lock base 50. However, the rotation prevention member is provided on the lock base 50 side in the initial state, and the rotation prevention member is moved to the bottom 78 side of the support member 76 when the spool 18 rotates in the pull-out direction with respect to the lock base 50. The shape and arrangement position of the rotation prevention member are not particularly limited.

  Further, in the present embodiment, the convex portion 82 as the rotation stop portion is formed on the support member 76 and the recess portion 84 as the rotation stop portion is formed on the spool 18. However, a configuration in which the concave portion 84 as the rotation stop portion is formed in the support member 76 and the convex portion 82 as the rotation stop portion is formed in the spool 18 may be adopted.

  Further, in the present embodiment, the support portion 88 is set to the convex portion 82, whereby the strength of the support portion 88 is higher than that of another portion of the support member 76. However, for example, various configurations can be widely applied to a configuration in which the strength of the support portion 88 is higher than that of another portion of the support member 76 such as heat treatment or surface treatment on the support portion 88 of the support member 76.

  Further, in the present embodiment, the convex portion 82 as the rotation stop portion is formed on the support member 76 and the recess portion 84 as the rotation stop portion is formed on the spool 18. However, a configuration in which the concave portion 84 as the rotation stop portion is formed in the support member 76 and the convex portion 82 as the rotation stop portion is formed in the spool 18 may be adopted.

  Further, in the present embodiment, the present invention is applied to the webbing take-up device 10 provided on the rear side of the rear seat. However, the present invention can be widely applied to a seat to which the webbing take-up device is applied, such as a webbing take-up device for a driver seat or a passenger seat, and the arrangement position of the webbing take-up device.

DESCRIPTION OF SYMBOLS 10 Webbing winding device 18 Spool 22 Insertion hole 24 Webbing 26 Loop part (base end part of webbing)
28 Webbing stopper (prevention member)
40 Torsion shaft (energy absorbing member)
50 Lock base 74 Fitting part 76 Support member 78 Bottom part 82 Convex part (rotating part)
84 Concave part (rotating part)
86 Insertion groove (insertion part)
88 Support part (support surface part)
90 Support surface 110 Webbing take-up device 114 FL stopper (rotation prevention member)

Claims (8)

A webbing provided with a retaining member at the base end,
A spool in which an insertion hole through which the webbing can pass is formed, and a base end portion of the webbing is locked on one side of the insertion hole by the retaining member;
A support member that is provided on the spool and has a mechanical strength higher than that of the spool, and when the webbing is pulled, a tensile load of the webbing is applied from the widthwise end of the base end of the webbing. When,
A webbing take-up device comprising:   The support member includes an insertion portion through which the webbing is penetrated and a pair of support surfaces which are formed by partially expanding an inner width of the insertion portion and to which the proximal end portion of the webbing is abutted. The webbing take-up device according to claim 1.   The said insertion part is made into the insertion groove opened toward the spool axial direction center side, and the said support member is continuing in the spool circumferential direction in the spool axial direction outer side rather than the said insertion groove. Webbing take-up device.   The webbing take-up device according to claim 2 or 3, wherein the strength of the support surface portion of the support member is set higher than other portions of the support member.   The webbing take-up device according to claim 4, wherein a convex portion is formed to protrude radially outward from the support member, and the support surface portion is set to the convex portion.   The webbing take-up device according to any one of claims 1 to 5, wherein the support member is attached to one end portion in the axial direction of the spool. A lock base which is provided so as to be rotatable integrally with the spool, and is limited in rotation in the pull-out direction in a vehicle emergency;
An energy absorbing member that is deformed by rotating the spool in the pull-out direction with respect to the lock base in an emergency of the vehicle and absorbs the rotational force of the spool;
When the spool is engaged with the support member, which is provided so as not to rotate relative to the spool, to rotate relative to the lock base a predetermined number of times, and the spool is pulled out in the pull-out direction with respect to the lock base, the spool is pulled out. A rotation blocking member that blocks rotation in the direction;
A webbing take-up device according to any one of claims 1 to 6, further comprising:   The webbing take-up device according to claim 7, wherein a plurality of rotation stop portions that prevent relative rotation between the support member and the spool are provided.

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