JP5226541B2 - Webbing take-up device - Google Patents

Description

  The present invention relates to a webbing take-up device that takes up and stores a webbing belt that restrains the body of an occupant of a vehicle.

  In the webbing take-up device, the rotation of the spool in the webbing withdrawal direction is locked when the vehicle suddenly decelerates to prevent the webbing belt from being withdrawn. In such a webbing take-up device, when the webbing belt is prevented from being pulled out, a so-called force limiter mechanism allows a predetermined amount of the webbing belt to be pulled out to absorb energy.

  As a force limiter mechanism, for example, a configuration in which a torsion shaft is disposed coaxially with a spool is generally used. In such a mechanism, a load (force limiter load) applied to the webbing belt when allowing the webbing belt to be drawn is generated by a torsional load of the torsion shaft. Further, for example, in the force limiter mechanism disclosed in Patent Document 1 below, in order to increase the force limiter load according to the webbing belt pull-out amount and maintain it to some extent, the intermediate portion of the torsion bar (torsion shaft) is moved to the spool side at a predetermined time. The structure is supported.

US Patent Application Publication No. 2006/0124795

  However, in the above prior art, the force limiter load is generated only by the torsional load of the torsion bar (torsion shaft), and therefore it is necessary to enlarge the torsion bar in the radial direction in order to secure a predetermined force limiter load. is there.

  In view of the above-described facts, the present invention provides a webbing take-up device that can increase the force limiter load to a predetermined high load according to the amount of webbing belt drawn without enlarging the torsion shaft in the radial direction. Is the purpose.

  In the webbing take-up device according to the first aspect of the present invention, the longitudinal base end side of the long belt-like webbing belt is locked, the webbing belt is wound around the outer peripheral portion, and the webbing take-up device is pulled out as the webbing belt is pulled out. A spool that rotates in a direction, and a lock base that is provided on a side of one end portion in the axial direction of the spool, is coaxial with the spool and is rotatable relative to the spool, and is rotatable when the rotational force of the spool is transmitted A lock means for restricting rotation of the lock base in the pull-out direction in at least one of a vehicle sudden deceleration state and a state in which the spool is rapidly rotated in the pull-out direction; and the spool inside the spool The lock base is integrally connected to the spool and is coaxially arranged with respect to the spool. A torsion shaft that torsionally deforms and allows rotation of the spool relative to the lock base when a rotational force greater than a predetermined magnitude in the pull-out direction is applied to the spool in a rotation-restricted state of the clutch base; It is arranged on either side of the lock base and the spool and can be moved together with either one, and the other end side is arranged on the other side of the lock base and the spool. The other side can be moved relative to the other, and the relative movement of the other end relative to the other after the spool rotates a predetermined amount in the pull-out direction with respect to the lock base is restricted by the other. The spool further rotates in the pull-out direction with respect to the lock base, so that the one end side is any one of the above. Having an elongated member to absorb energy, the are is sequentially bent while being pulled from the arrangement position of the side.

  According to the webbing take-up device of the present invention described in claim 1, the spool winds the webbing belt around the outer peripheral portion and rotates in the drawing direction as the webbing belt is pulled out. On the other hand, the lock base is coaxial with the spool and is rotatable relative to the spool, and is rotatable when the rotational force of the spool is transmitted. Here, when at least one of the vehicle sudden deceleration state and the state in which the spool is suddenly rotated in the pull-out direction, the lock means restricts the rotation of the lock base in the pull-out direction. Since the lock base is connected to the spool via the torsion shaft, the rotation of the spool in the pull-out direction is restricted by restricting the rotation of the lock base in the pull-out direction. As a result, the withdrawal of the webbing belt from the spool is restricted, and the body of the passenger wearing the webbing belt is strongly restrained by the webbing belt.

  In this state, for example, if the webbing belt is suddenly pulled by the occupant's body due to the inertia at the time of sudden deceleration of the vehicle and a rotational force of a predetermined magnitude or more in the pulling direction is applied to the spool, the torsion shaft is twisted. Due to the deformation, the spool rotates in the pull-out direction while the rotation restriction of the lock base is maintained, and the webbing belt can be pulled out from the spool by this rotation. At this time, the torsional load of the torsion shaft acts on the webbing belt as a force limiter load.

  On the other hand, on one side of the lock base and the spool, one end side of the long member is disposed so as to be movable together with either one of the above. On the other hand, the other end side of the long member is disposed on the other side of the lock base and the spool and can move relative to the other side. After the spool rotates by a predetermined amount in the pull-out direction with respect to the lock base, the long member is restricted by the other end relative to the other and is controlled by the other. As the spool further rotates in the pull-out direction, the other end side moves relative to either one of the above, and the one end side is sequentially bent while being pulled out from the arrangement position on either one of the sides, and energy is saved. Absorb.

  In other words, after the torsional load of the torsion shaft is generated, the deformation load of the long member is generated at the timing when the webbing belt is pulled out from the spool, and this deformation load is applied as a force limiter load and acts on the webbing belt. To do. For this reason, the force limiter load becomes a predetermined high load in accordance with the pulling amount of the webbing belt.

  According to a second aspect of the present invention, there is provided the webbing take-up device according to the first aspect, wherein the spool and the lock base are coaxial with the spool and the lock base and relatively rotatable. The rotating body is supported by penetrating the other end of the elongated member.

  According to the webbing take-up device of the present invention described in claim 2, the rotating body provided between the spool and the lock base is coaxial with the spool and the lock base and is relatively rotatable, and has a long shape. The other end side of the member is penetrated and supported. For this reason, when the one end side is pulled out from the arrangement position, the long member is pulled out from the arrangement position in a state where the other end side is supported by the rotating body.

  As described above, according to the webbing take-up device according to the first aspect of the present invention, the force limiter load is set according to the amount of webbing belt withdrawn without enlarging the torsion shaft in the radial direction. It has an excellent effect of being able to increase to a high load.

  According to the webbing take-up device according to claim 2, the support strength on the other end side of the elongate member when the one end side of the elongate member is pulled out from the arrangement position is ensured with a relatively simple configuration. It has an excellent effect of being able to.

It is a front sectional view showing an outline of composition of a webbing winding device concerning a 1st embodiment of the present invention. It is a disassembled perspective view which shows the outline of a structure of the principal part of the webbing take-up device according to the first embodiment of the present invention. It is a typical sectional side view which shows the operation state of the principal part of the webbing take-up device according to the first embodiment of the present invention (corresponding to a sectional view taken along line 3-3 in FIG. 1). FIG. 3A shows a state before the head of the wire moves along the groove portion of the lock base. FIG. 3B shows a state in which the head of the wire is in contact with the stopper of the groove. It is a graph which shows the FL load characteristic of the webbing winding device concerning a 1st embodiment of the present invention. It is front sectional drawing which shows the outline of a structure of the webbing winding apparatus which concerns on the 2nd Embodiment of this invention. It is a disassembled perspective view which shows the outline of a structure of the principal part of the webbing winding device concerning a 2nd embodiment of the present invention. It is a disassembled perspective view which shows the outline of a structure of the principal part of the webbing winding device concerning a 3rd embodiment of the present invention. It is a typical sectional side view which shows the operation state of the principal part of the webbing retractor which concerns on the 3rd Embodiment of this invention. FIG. 8A shows a state before the head of the wire moves along the groove portion of the lock base. FIG. 8B shows a state in which the head of one wire is in contact with the stopper of the groove. It is a typical sectional side view which shows the operation state of the principal part of the webbing winding device concerning a 3rd embodiment of the present invention, and shows the state where both the heads of a wire contacted the stopper part of a slot.

[First Embodiment]
FIG. 1 is a front sectional view showing an outline of the configuration of a webbing take-up device 10 according to the first embodiment of the present invention. FIG. 2 is an exploded perspective view showing the main part of the webbing take-up device 10. It is shown by the figure.

  As shown in FIG. 1, the webbing take-up device 10 includes a frame 12 that is fastened and fixed to a predetermined part of the vehicle body. The frame 12 includes a pair of leg plates 14 and 16. Each of the leg plates 14 and 16 is formed in a flat plate shape, and is opposed to each other in the thickness direction thereof. A spool 18 is disposed between the leg plate 14 and the leg plate 16. The spool 18 is formed in a substantially cylindrical shape whose axial direction is along the opposing direction of the leg plate 14 and the leg plate 16 (see FIG. 2), and is rotatable around its own central axis.

  A longitudinal base end portion (base end side) of the long belt-like webbing belt 20 is engaged with the spool 18. When the spool 18 rotates in the winding direction (in the direction of arrow A in FIG. 2), which is one side around its own central axis, the webbing belt 20 is wound in layers from the base end side in the longitudinal direction to the outer peripheral portion. When the webbing belt 20 is pulled toward the front end side, the webbing belt 20 wound around the spool 18 is pulled out, and the spool 18 rotates in the pulling direction opposite to the winding direction (arrow B direction in FIG. 2).

  An adapter 22 is provided on the leg plate 14 side of the spool 18. The adapter 22 is fitted in a fitting insertion hole 24 opened at the end of the spool 18 on the leg plate 14 side. The inner circumferential shape of the fitting insertion hole 24 and the outer circumferential shape of the adapter 22 are non-circular, and the adapter 22 fitted into the fitting insertion hole 24 is not allowed to rotate relative to the spool 18 around the central axis of the spool 18. When one of the spool 18 and the adapter 22 rotates around the center axis of the spool 18, the other rotates integrally.

  The adapter 22 passes through the leg plate 14 and enters a spring housing 26 fixed to the frame 12 on the side of the leg plate 14 (on the side opposite to the leg plate 16 via the leg plate 14). It is supported by the spring housing 26 so as to be rotatable around the central axis. The spring housing 26 accommodates biasing means (not shown) such as a spiral spring. A part of this urging means is directly or indirectly connected to the adapter 22, and when the adapter 22 rotates in the pull-out direction, the adapter 22 is urged in the winding direction. The adapter 22 may be one of the components of a pretensioner that instantaneously rotates the spool 18 in the winding direction when the vehicle suddenly decelerates.

  On the other hand, a lock base 34 (also referred to as “base lock” or “lock gear”) is provided on the side (leg plate 16 side) of one end of the spool 18 in the axial direction. The lock base 34 is coaxial with the spool 18 and includes a cylindrical fitting insertion portion 36 having a relatively short axial dimension. A fitting insertion hole 38 is formed in the spool 18 corresponding to the fitting insertion portion 36. The inner circumferential shape of the fitting insertion hole 38 is a circle that is coaxial with the spool 18 and opens at the end face of the spool 18 on the leg plate 16 side. The inner diameter dimension of the fitting hole 38 is slightly larger than the outer diameter dimension of the fitting part 36, and when the fitting part 36 is fitted in the fitting hole 38, the inner diameter dimension of the spool 18 extends around the center axis of the spool 18. On the other hand, the lock base 34 is relatively rotatable.

  The lock base 34 includes a ratchet portion 40. The ratchet portion 40 is an external toothed ratchet wheel, is formed coaxially with the fitting insertion portion 36, and in the state where the fitting insertion portion 36 is fitted into the fitting insertion hole 38, the leg plate 16 side of the spool 18. It is arrange | positioned so that it may adjoin to the end surface.

  On the side of the leg plate 16 and on the side opposite to the leg plate 14 via the leg plate 16 (that is, the side of one end portion in the axial direction of the spool 18), the housing 32 of the lock mechanism 30 as a lock means is a frame. 12 is fixed. Note that since a known locking mechanism can be applied to the locking mechanism 30, a detailed description thereof will be omitted, but a brief description will be given below.

  The lock mechanism 30 includes a lock pawl 42. The lock pawl 42 is disposed in the vicinity of the ratchet portion 40 along the rotational radius direction of the lock base 34, and is supported by the leg plate 16 so as to be rotatable around an axis whose axial direction is the same as the axial direction of the spool 18. ing.

  The lock pawl 42 is moved toward and away from the outer peripheral portion of the ratchet portion 40 by rotating. Further, the lock pawl 42 is formed with lock teeth 46 that can mesh with the ratchet teeth 44 formed on the outer peripheral portion of the ratchet portion 40, and the lock pawl 42 is directed toward the outer peripheral portion of the ratchet portion 40. When it rotates, as shown in FIG. 3, the lock teeth 46 of the lock pawl 42 mesh with the ratchet teeth 44 of the ratchet portion 40. In the state where the lock teeth 46 are engaged with the ratchet teeth 44, the rotation of the ratchet portion 40, that is, the lock base 34 in the pull-out direction (arrow B direction) is restricted.

  In addition to the lock pawl 42, various members such as a sensor gear (not shown) and an acceleration sensor (not shown) constituting the lock mechanism 30 are accommodated inside the housing 32 shown in FIG. The lock mechanism 30 operates in at least one of a state in which the vehicle on which the webbing take-up device 10 is mounted is rapidly decelerated and a state in which the spool 18 is suddenly rotated in the pull-out direction, and the sensor gear (not shown) is operated. The lock pawl 42 is pressed, and the lock pawl 42 is rotated in the direction in which the lock teeth 46 are brought close to and engaged with the ratchet teeth 44. As a result, the lock teeth 46 of the lock pawl 42 mesh with the ratchet teeth 44, and the rotation of the lock base 34 in the pull-out direction is restricted.

  On the other hand, a through hole 48 is formed through the spool 18. The through hole 48 is formed coaxially with the spool 18, and one end thereof opens at the bottom of the fitting insertion hole 38 and the other end opens at the bottom of the fitting insertion hole 24. Inside the spool 18 (including the inside of the through hole 48), a torsion shaft 50 (also referred to as a “torsion bar”, which is an element grasped as a “load absorbing member” or “connecting member” in a broad sense). 18 is arranged coaxially. The torsion shaft 50 is connected to the adapter 22 in a state in which relative rotation around the central axis of the spool 18 with respect to the adapter 22 is impossible at the end on the leg plate 14 side.

  Further, the torsion shaft 50 is coupled to the insertion portion 36 (lock base 34) at the end on the leg plate 16 side in a state in which relative rotation around the central axis of the spool 18 with respect to the insertion portion 36 (lock base 34) is impossible. ing. Thus, the torsion shaft 50 integrally connects the lock base 34 to the spool 18. That is, as described above, although the lock base 34 has the insertion portion 36 inserted into the insertion hole 38 so as to be rotatable relative to the spool 18 around the center axis of the spool 18, the torsion shaft 50 is connected to the spool 18. Since the relative rotation around the central axis of the spool 18 is impossible with respect to both the lock base 34 and the lock base 34, the lock base 34 is basically not rotatable relative to the spool 18. Rotate integrally (that is, the lock base 34 rotates when the rotational force of the spool 18 is transmitted).

  Further, from this, when the lock teeth 46 of the lock pawl 42 mesh with the ratchet teeth 44 of the lock base 34, the rotation of the spool 18 in the pull-out direction is restricted. However, the torsion shaft 50 is torsionally deformed and applied to the lock base 34 when a rotational force greater than a predetermined magnitude in the pull-out direction is applied to the spool 18 in a state where the lock base 34 is restricted by the lock mechanism 30. The spool 18 is allowed to rotate.

  On the other hand, as shown in FIGS. 1 and 2, an annular groove 52 is formed at an end portion (one axial end portion) of the spool 18 on the leg plate 16 side. As shown in FIG. 2, the annular groove 52 has a circular shape coaxial with the center axis of the spool 18 at a position spaced apart from the center axis (rotation axis position) of the spool 18 in the rotational radius direction. 18 is opened at the end face of the leg plate 16 side. Further, as shown in FIGS. 1 and 2, an insertion hole 54 is formed in the spool 18. One end of the insertion hole 54 opens at the bottom of the annular groove 52, and the other end opens at the end face of the spool 18 on the leg plate 14 side as shown in FIG. 1. The direction from one end to the other end of the insertion hole 54 is the same as the direction of the central axis of the spool 18.

  As shown in FIG. 2, the webbing retractor 10 is an element grasped as a load absorbing wire 60 (a (long) load absorbing member in a broad sense) as a long member. Yes.) The wire 60 is formed by bending a bar made of a hard material at two locations, a first bent portion 63 and a second bent portion 65, into a crank shape, and an insertion portion 62 is provided on one end side. I have. The insertion portion 62 is a portion that is inserted into the insertion hole 54 of the spool 18 and is accommodated (arranged), and has a bar shape with a circular cross section that is formed in a tapered shape with a tapered tip. The outer diameter dimension of the insertion portion 62 is not more than the inner diameter dimension of the insertion hole 54 and not more than the inner width dimension of the annular groove 52 (dimension along the radial direction of the spool 18 in the annular groove 52). Further, the insertion portion 62 is movable together with the spool 18 while being accommodated (arranged) in the insertion hole 54 of the spool 18. In the present embodiment, the spool 18 is “one of the lock base and the spool” recited in claim 1.

  A curved portion 64 is continuously formed at the end portion on the first bent portion 63 side which is the base end side of the insertion portion 62. The curved portion 64 has a short rod shape whose outer diameter is equal to or smaller than the inner width dimension of the annular groove 52, and has a curved shape that can be accommodated along the annular groove 52. At the end of the bending portion 64 opposite to the insertion portion 62 (that is, the second bent portion 65 side), a locking portion 66 is continuously formed in a short straight bar shape.

  A head 68 is continuously formed at the end of the locking portion 66 opposite to the curved portion 64. The head portion 68 that is the other end side of the wire 60 is arranged on the side of one end portion in the axial direction of the spool 18 (details will be described later), and its outer diameter is larger than that of the locking portion 66. It is the diameter.

  As described above, since the bending portion 64 of the wire 60 has a curved shape that can be accommodated along the annular groove 52 of the spool 18, the bending portion 64 is not inserted in the state where the insertion portion 62 is inserted into the insertion hole 54. It can enter the annular groove 52. In a state where the curved portion 64 is inserted into the annular groove 52, the axial center of the locking portion 66 is slightly shifted from the axial center of the insertion portion 62 around the axial center of the spool 18.

  As shown in FIGS. 1 and 2, a wire holder 70 as a rotating body is provided between the spool 18 and the lock base 34. The wire holder 70 is formed in a thin disk shape (annular shape).

  An insertion hole 72 is formed in the wire holder 70 so as to correspond to the insertion portion 36 of the lock base 34. The fitting hole 72 has a circular inner shape that is coaxial with the lock base 34 and the spool 18. The inner diameter dimension of the insertion hole 72 is slightly larger than the outer diameter dimension of the insertion part 36, and in a state where the insertion part 36 is inserted into the insertion hole 72, the lock base is formed around the central axis of the spool 18. The wire holder 70 can be rotated relative to the spool 34 and the spool 18. That is, the wire holder 70 is coaxial with the spool 18 and the lock base 34 and is relatively rotatable, and in the present embodiment, the torsion shaft 50 penetrates rotatably.

  The wire holder 70 is formed with a support hole 74 for penetrating and supporting the other end of the wire 60 in the thickness direction of the wire holder 70 (the same direction as the central axis of the wire holder 70). Yes. In the assembled state, the locking portion 66 of the wire 60 is disposed inside the support hole 74.

  Further, as shown in FIG. 2, a groove portion 56 is formed at a portion of the lock base 34 facing the wire holder 70. As shown in FIGS. 2 and 3, the groove portion 56 is provided at a position where the head portion 68 of the wire 60 can be disposed, and is a circle centering on the central axis of the lock base 34 (the central axis of the spool 18). It is formed in an arc shape and opens at the end surface of the lock base 34 facing the wire holder 70 side. The inner width dimension of the groove portion 56 (the dimension along the radial direction of the lock base 34 in the groove portion 56) is constant, and is set to be slightly larger than the diameter of the head portion 68 of the wire 60. As a result, the head portion 68 of the wire 60 is disposed in the groove portion 56 on the lock base 34 side and can be moved relative to the lock base 34. In this embodiment, the lock base 34 is “one of the lock base and the spool” described in claim 1.

  Further, a groove edge portion on the terminal end side in the drawing direction (arrow B direction) of the spool 18 in the groove portion 56 is a stopper portion 58 (regulating portion). This stopper portion 58 directly restricts the relative rotational movement of the head 68 of the wire 60 relative to the lock base 34 after the spool 18 has rotated a predetermined amount in the pull-out direction (arrow B direction) with respect to the lock base 34 ( (See FIG. 3B). In other words, the relative movement of the head 68 (on the other end side) of the wire 60 with respect to the lock base 34 (as the other) is restricted by a part of the lock base 34.

  With the above configuration, the wire 60 has the head on the other end side with respect to the lock base 34 by the stopper portion 58 on the lock base 34 side after the spool 18 rotates a predetermined amount in the pull-out direction (arrow B direction) with respect to the lock base 34. The relative movement of 68 is restricted, and the spool 18 further rotates in the pull-out direction (arrow B direction) with respect to the lock base 34, so that the insertion portion 62 on one end side shown in FIG. While being pulled out from (accommodating position (arrangement position)), it is sequentially bent (transformed while being extracted) to absorb energy.

(Action / Effect)
Next, the operation and effect of the above embodiment will be described.

  In the webbing retractor 10 shown in FIG. 1, the vehicle is decelerated when the webbing belt 20 pulled out from the spool 18 is attached to the body of an occupant of the vehicle. The lock mechanism 30 is activated when (not shown) is detected, or when the spool 18 abruptly rotates in the pull-out direction due to the occupant's body pulling the spool 18 abruptly due to inertia in the vehicle deceleration state. When the lock mechanism 30 is actuated, the lock pawl 42 rotates in a direction approaching the ratchet portion 40 of the lock base 34, and thereby the lock teeth 46 of the lock pawl 42 mesh with the ratchet teeth 44 of the ratchet portion 40.

  Thereby, the rotation of the lock base 34 in the pull-out direction is restricted, and consequently the rotation of the spool 18 connected to the lock base 34 via the torsion shaft 50 is restricted in the pull-out direction. In this way, by restricting the rotation of the spool 18 in the pull-out direction, the pull-out of the webbing belt 20 wound around the spool 18 is restricted, so that the inertial movement toward the vehicle front side during sudden deceleration of the vehicle is attempted. The body of the occupant is strongly restrained by the webbing belt 20.

  In such a state, when the webbing belt 20 is pulled by the body of an occupant who intends to move inertially toward the front side of the vehicle, the rotational force applied to the spool 18 in the pull-out direction exceeds the mechanical strength of the torsion shaft 50. When it becomes larger than a predetermined size, plastic deformation starts so that the leg plate 14 side is twisted in the pull-out direction with respect to the leg plate 16 side of the torsion shaft 50, and the lock pawl 42 rotates in the pull-out direction. The spool 18 starts to rotate in the pull-out direction with respect to the restricted lock base 34. The webbing belt 20 can be pulled out of the spool 18 by this amount of rotation. At this time, the torsional load of the torsion shaft 50 acts on the webbing belt 20 as a force limiter load.

  When the spool 18 starts to rotate in the pull-out direction with respect to the lock base 34 as described above, the head portion 68 of the wire 60 extends along the formation direction of the groove portion 56 formed in the lock base 34 as shown in FIG. It rotates around the central axis of the lock base 34 (the central axis of the spool 18). At this time, the wire holder 70 rotates relative to the lock base 34 together with the spool 18 as the wire 60 rotates. For this reason, the deformation load of the wire 60 does not occur.

  When the spool 18 rotates relative to the lock base 34 by a predetermined amount (slightly less than one rotation in this embodiment) in the pull-out direction, the head portion 68 of the wire 60 becomes the stopper portion of the groove portion 56 as shown in FIG. 58, the relative rotational movement with respect to the lock base 34 is restricted. As a result, the head portion 68 and the locking portion 66 of the wire 60 are held (locked) at predetermined positions by the stopper portion 58 of the groove portion 56 and the support hole 74 (see FIG. 1) of the wire holder 70, and then further When the spool 18 rotates in the pull-out direction (arrow B direction) with respect to the lock base 34, the insertion portion 62 of the wire 60 shown in FIG. 1 comes out of the insertion hole 54 (drawn from the accommodation position (arrangement position)). .) The insertion portion 62 that has come out of the insertion hole 54 in this way is deformed by being squeezed by the opening edge of the insertion hole 54 (that is, it is continuously bent and absorbs energy). The groove 52 bends in the circumferential direction of the groove 52 (see FIG. 2) and bends following the annular groove 52.

  That is, after the torsional load of the torsion shaft 50 is generated, a deformation load of the wire 60 is generated at a timing when the webbing belt 20 is pulled out from the spool 18 by a predetermined amount, and this deformation load is applied as a force limiter load. Act on. Thus, in this webbing take-up device 10, the force limiter load is controlled by shifting the operation timing of the torsion shaft 50 and the wire 60 (additional load control of the two-stage force limiter). For this reason, the force limiter load becomes a predetermined high load according to the drawing amount of the webbing belt 20.

  In addition, since a part of the load on the holding side (the other end side) of the wire 60 at this time is supported by the hole portion of the support hole 74 of the wire holder 70 at the locking portion 66, the locking portion 66 of the wire 60. The support strength on the head 68 side is ensured by a relatively simple configuration. The deformation load of the wire 60 acting as a force limiter load continues until the insertion portion 62 of the wire 60 is completely pulled out of the insertion hole 54 and the deformation of the wire 60 is completed.

  FIG. 4 is a graph showing the FL load characteristics (force limiter load characteristics) of the webbing take-up device 10 according to this embodiment. The FL load F1 is a deformation load of the torsion shaft 50, and the FL load F2 is the sum of the deformation load of the torsion shaft 50 and the deformation load of the wire 60. Further, the stroke S1 is a stroke when the head portion 68 of the wire 60 shown in FIG. 3B comes into contact with the stopper portion 58 of the groove portion 56, and the stroke S2 is the insertion portion 62 of the wire 60. This is the stroke at the time when the wire 60 is completely deformed through the insertion hole 54 and the deformation of the wire 60 is completed. As shown in this figure, in the webbing take-up device 10, the force limiter load is increased in accordance with the amount of the webbing belt 20 pulled out, so that energy is absorbed.

  As described above, according to the webbing take-up device 10 according to the present embodiment, the force limiter load is set to a predetermined high load according to the pull-out amount of the webbing belt 20 without enlarging the torsion shaft 50 in the radial direction. Can be raised.

[Second Embodiment]
Next, a webbing take-up device according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a front sectional view (similar to FIG. 1 of the first embodiment) of the configuration of the webbing retractor 80 according to the second embodiment of the present invention, and FIG. FIG. 2 shows an exploded perspective view (a diagram corresponding to FIG. 2 of the first embodiment) of the main part of the webbing take-up device 80.

  As shown in these drawings, the webbing take-up device 80 is configured such that a groove portion 82 is formed in the wire holder 70 instead of the groove portion 56 (see FIG. 2 and the like) of the lock base 34, and a stopper portion 84 is formed in the lock base 34. The webbing retractor 10 according to the first embodiment is different in that (see FIG. 6) is formed. Other configurations are substantially the same as those of the first embodiment. Therefore, components that are substantially the same as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. Also in this embodiment, the spool 18 is “one of the lock base and the spool” according to claim 1, and the lock base 34 is “the other of the lock base and the spool” according to claim 1. It has become.

  The groove portion 82 formed in the wire holder 70 is provided in a portion facing the lock base 34 and is formed in an arc shape centering on the center axis of the wire holder 70 (center axis of the spool 18). Opened at the end face directed to the 34th side. The inner width dimension of the groove part 82 (the dimension along the radial direction of the wire holder 70 in the groove part 82) is constant. In the present embodiment, a support hole 74 is formed through the groove 82 at the terminal end in the winding direction (arrow A direction), and one end of the support hole 74 is open at the bottom of the groove 82. .

  On the other hand, as shown in FIG. 6, the stopper portion 84 formed on the lock base 34 is provided in a position that can be disposed in the groove portion 82 of the wire holder 70 at a portion facing the wire holder 70, and has a short cylindrical shape. The diameter is set to be slightly smaller than the inner width dimension of the groove 82. The stopper portion 84 directly restricts the relative rotational movement of the head 68 of the wire 60 relative to the lock base 34 after the spool 18 has rotated a predetermined amount in the pull-out direction (arrow B direction) with respect to the lock base 34 ( Stop). Even with such a configuration, the same operations and effects as the first embodiment described above can be obtained.

[Third Embodiment]
Next, a webbing take-up device according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 7 shows an exploded perspective view (a diagram corresponding to FIG. 2 of the first embodiment) of the main part of the webbing retractor 90 according to the third embodiment of the present invention. 8 and FIG. 9 are schematic side sectional views showing the operating state of the main part of the webbing take-up device 90.

  As shown in these drawings, the webbing take-up device 90 has a configuration in which a plurality of (two in the present embodiment) elongated members 60 and 92 are disposed. This is different from the webbing take-up device 10 according to the first embodiment (see FIG. 2 and the like). Other configurations are substantially the same as those of the first embodiment. Therefore, components that are substantially the same as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted. Also in this embodiment, the spool 18 is “one of the lock base and the spool” according to claim 1, and the lock base 34 is “the other of the lock base and the spool” according to claim 1. It has become.

  As shown in FIG. 7, the webbing take-up device 90 includes a plurality of (two in this embodiment) wires 60 and 92. The wire 92 has the same configuration as that of the wire 60 and includes an insertion portion 94 similar to the insertion portion 62 on one end side and a head 100 similar to the head 68 on the other end side. . Further, in the wire 92, between the insertion portion 94 and the head 100, a first bent portion 95 similar to the first bent portion 63, a bent portion 96 similar to the bent portion 64, and a second bent portion 65 The same second bent part 97 and the same locking part 98 as the locking part 66 are formed.

  The insertion portion 94 of the wire 92 is inserted and accommodated (arranged) in an insertion hole 102 formed in the spool 18. As with the insertion hole 54, one end of the insertion hole 102 opens at the bottom of the annular groove 52 and penetrates in the direction of the center axis of the spool 18. Further, the insertion hole 102 is formed at a position shifted around the center axis of the spool 18 from the position opposite to the insertion hole 54 across the center axis of the spool 18.

  Corresponding to the insertion hole 102, the wire holder 70 is formed with a support hole 104 for penetrating and supporting the other end side of the wire 92. The support hole 104 is formed at a position shifted from the position opposite to the support hole 74 around the center axis of the wire holder 70 across the center axis of the wire holder 70, and in the thickness direction of the wire holder 70 (the center of the wire holder 70. Penetrates in the same direction as the axis). Further, in the assembled state, the locking portion 98 of the wire 92 is disposed inside the support hole 104.

  The head portion 100 of the wire 92 is disposed in a groove portion 106 formed in the lock base 34. The groove 106 is formed in a semicircular arc shape centering on the central axis of the lock base 34 (the central axis of the spool 18) at the portion of the lock base 34 facing the wire holder 70, and toward the wire holder 70 side of the lock base 34. Open at the directed end face. As a result, the head portion 100 of the wire 92 is disposed in the groove portion 106 on the lock base 34 side and can be moved relative to the lock base 34. On the other hand, the groove portion 56 formed in the lock base 34 is slightly weaker around the central axis of the lock base 34 in the first embodiment, but is formed in an arc shape shorter than the semicircular arc in the present embodiment. Has been. That is, the groove 106 is set to be longer in the arc direction than the groove 56.

  Further, the groove edge portion on the terminal end side in the drawing direction (arrow B direction) of the spool 18 in the groove portion 106 is a stopper portion 108 (regulating portion). The stopper portion 108 directly regulates the relative rotational movement of the head portion 100 of the wire 92 with respect to the lock base 34 after the spool 18 has rotated a predetermined amount in the pull-out direction (arrow B direction) with respect to the lock base 34 ( (See FIG. 9). In other words, the relative movement of the head 100 (on the other end side) of the wire 92 with respect to the lock base 34 (as the other) is restricted by a part of the lock base 34.

  With the above configuration, the wire 92 has a head on the other end side with respect to the lock base 34 by the stopper 108 on the lock base 34 side after the spool 18 rotates a predetermined amount in the pull-out direction (arrow B direction) with respect to the lock base 34. The relative movement of 100 is restricted, and the spool 18 further rotates in the pull-out direction (arrow B direction) with respect to the lock base 34, so that the insertion portion 94 on one end side is inserted into the insertion hole 102 (accommodation position (arrangement position)). The energy is absorbed by being sequentially bent (extracted and deformed) while being pulled out from the installation position)).

(Action / Effect)
Next, the operation and effect of the above embodiment will be described.

  When the spool 18 starts to rotate in the pull-out direction (arrow B direction) with respect to the lock base 34, the head portion 68 of the wire 60 rotates along the direction in which the groove portion 56 of the lock base 34 is formed, as shown in FIG. While moving, the head portion 100 of the wire 92 rotates and moves along the direction in which the groove portion 106 of the lock base 34 is formed. At this time, the wire holder 70 rotates relative to the lock base 34 together with the spool 18 as the wires 60 and 92 rotate. For this reason, the deformation load of the wires 60 and 92 is not generated.

  When the spool 18 rotates relative to the lock base 34 by a predetermined amount in the pull-out direction (arrow B direction), the head portion 68 of the wire 60 first contacts the stopper portion 58 of the groove portion 56 as shown in FIG. The relative rotational movement of the wire 60 with respect to the lock base 34 is restricted. Thereafter, when the spool 18 rotates in the pull-out direction (arrow B direction) with respect to the lock base 34, the insertion portion 62 of the wire 60 shown in FIG. As shown in FIG. 9, the head portion 100 of the wire 92 abuts against the stopper portion 108 of the groove portion 106, and the wire 92 rotates relative to the lock base 34. Movement is restricted.

  Thereafter, the spool 18 further rotates in the pull-out direction (arrow B direction) with respect to the lock base 34, whereby the insertion portion 94 of the wire 92 shown in FIG. 7 comes out of the insertion hole 102 (from the accommodation position (arrangement position)). Pulled out.) Thus, the insertion portion 94 that has come out of the insertion hole 102 is deformed by being squeezed by the opening edge of the insertion hole 102 (that is, it is sequentially bent and absorbs energy), and is bent in the circumferential direction of the annular groove 52. At the same time, it is curved following the annular groove 52.

  That is, after a torsional load of the torsion shaft 50 is generated, first, a deformation load of the wire 60 is generated at a timing when the webbing belt 20 is pulled out from the spool 18, and then the webbing belt 20 is pulled out from the spool 18. The deformation load of the wire 92 is generated at the same timing. These deformation loads are applied as force limiter loads and act on the webbing belt 20. Thus, in the webbing take-up device 90, the force limiter load is controlled by shifting the operation timing of the torsion shaft 50, the wire 60, and the wire 92. For this reason, the force limiter load becomes a predetermined high load according to the drawing amount of the webbing belt 20.

[Fourth Embodiment]
Although not shown in the drawings, as a fourth embodiment, as a long member, one end side of the wire is accommodated (arranged) on the lock base side so that it can be moved together with the lock base, and the other end side is The spool is disposed on the spool side so as to be relatively movable with respect to the spool, and after the spool rotates a predetermined amount in the pull-out direction with respect to the lock base, relative movement on the other end side of the wire with respect to the spool is restricted by the spool. By further rotating the spool in the pull-out direction with respect to the lock base, one end side of the wire may be sequentially bent while being pulled out from the accommodation position (arrangement position) of the lock base to absorb energy.

  More specifically, for example, as a modified example of the configuration shown in FIG. 2, the spool 18 has an arcuate groove portion that opens to the wire holder 70 side corresponding to the groove portion 56 instead of the annular groove 52. The head portion 68 of the wire 60 is formed in the groove portion, and the lock base 34 has a circular annular groove corresponding to the annular groove 52 and opened to the wire holder 70 instead of the groove portion 56. The one end side of the wire 60 is formed through the lock base 34 in the thickness direction at a predetermined portion of the annular groove, and the one end side of the wire 60 penetrating the lock base 34 is the wire holder 70 in the lock base 34. You may make it the structure which is wound and arrange | positioned in the circular-arc-shaped accommodation groove part (or cylindrical part) centering on the center axis line of the lock base 34 in the site | part on the opposite side.

[Supplementary explanation of the embodiment]
The stopper portions 58, 84, 108 of the first to third embodiments are the heads of the wires 60, 92 after the spool 18 rotates a predetermined amount in the pull-out direction (arrow B direction) with respect to the lock base 34. Although the relative rotational movement of 68 and 100 with respect to the lock base 34 is directly restricted (stopped) by contact, the stopper portion formed on the lock base has a predetermined amount in the pull-out direction with respect to the lock base. It may be a stopper portion that indirectly restricts the relative rotational movement of the other end of the elongated member with respect to the lock base after rotation. As an example, for example, the groove portion 82 of the wire holder 70 shown in FIG. 6 is formed away from the support hole 74, and after the spool 18 rotates a predetermined amount in the pulling direction (arrow B direction) with respect to the lock base 34, the stopper portion 84. Abuts against the groove edge portion of the groove portion (groove portion formed away from the support hole 74), thereby restricting (stopping) the relative rotational movement of the wire holder 70 and the head portion 68 of the wire 60 with respect to the lock base 34. It may be configured.

  Moreover, in the said embodiment, although the elongate member is comprised with the wires 60 and 92, an elongate member is good also as another elongate member like a plate etc., such as this, There may be a plurality of other elongated members.

  In the above embodiment, the initial shape of the wires 60 and 92 is a crank shape, but the initial shape of the wire as the long member may be a linear shape.

  Furthermore, in the first to third embodiments, the wire holder 70 as a rotating body provided between the spool 18 and the lock base 34 penetrates and supports the other ends of the wires 60 and 92. For example, a structure in which the other end side of the long member is directly supported by the lock base may be provided without providing such a wire holder 70.

  Furthermore, as a modification of the first and second embodiments, for example, a rotating member is arranged between the wire holder 70 and the lock base 34 to restrict relative rotational movement on the other end side of the wire 60 with respect to the lock base 34. It is good also as a structure which further delays the timing to perform. As an example, for example, an annular rotating member having the same size as the wire holder 70 is arranged between the wire holder 70 and the lock base 34 in FIG. A groove portion similar to the groove portion 56 may be formed, and a short cylindrical portion disposed in the groove portion 56 of the lock base 34 may be formed at a portion facing the lock base 34 of the rotating member. Further, a single or a plurality of rotating members similar to the rotating member may be disposed between the rotating member and the lock base 34.

  In the first to third embodiments, the insertion holes 54 and 102 pass through the spool 18 in the central axis direction of the spool 18, but the insertion hole is on the leg plate (14) side of the spool (18). It may be an insertion hole that is not open on the end face (on the other end side in the axial direction). Further, the spool (18) is formed at substantially the same position as the insertion hole (54, 102) instead of the insertion hole (54, 102), and an outer peripheral portion (webbing belt (20) of the spool (18) is formed. An accommodation groove portion opened on the winding side) may be formed, and the wires (60, 92) may be accommodated (arranged) in the accommodation groove portion.

  That is, even if the spool (18) is not formed with the insertion holes (54, 102), the spool (18) is supported on the inner side of the wire (60, 92) when the wires (60, 92) are sequentially bent. One support part (first wall part, pin, etc.) is formed, and the wire (60, 92) is opposite to the first support part (for example, diagonally opposite) across the wire (60, 92). A second support portion (second wall portion or pin) that supports one end side (tip end side) of the wire (60, 92) on the side opposite to the side where the wire (60, 92) is bent when sequentially bent. Etc.) may be formed. In addition, the relative movement of the other end side (heads 68, 100 and locking portions 66, 98) of the wires (60, 92) with respect to the lock base (34) is regulated at a predetermined position by contact. If the three support portions (the third wall portion, the pins, etc.) are formed on the lock base (34), the spool (18) of the wires (60, 92) is pulled out from the lock base (34) ( After being rotated a predetermined amount in the direction of arrow B), it is bent sequentially.

  Moreover, in the said 1st-3rd embodiment, although the annular groove 52 is formed in the edge part (axial direction one end part) by the side of the leg plate 16 of the spool 18, such an annular groove is a wire holder as a rotary body. (70) may be formed at a portion facing the spool (18).

10 Webbing take-up device 18 Spool 20 Webbing belt 30 Lock mechanism (locking means)
34 Lock base 50 Torsion shaft 60 Wire (long member)
70 Wire holder (rotating body)
80 Webbing take-up device 90 Webbing take-up device 92 Wire (long member)
B Pull-out direction

Claims (2)

A longitudinal belt-like base end side of the belt-like webbing belt is locked, and the spool that winds the webbing belt around the outer periphery and rotates in the pull-out direction as the webbing belt is pulled out;
A lock base provided on the side of one end of the spool in the axial direction, coaxial with the spool and rotatable relative to the spool, and rotatable by transmitting the rotational force of the spool;
Lock means for restricting rotation of the lock base in the pull-out direction in at least one of a vehicle rapid deceleration state and a state in which the spool is rapidly rotated in the pull-out direction;
The lock base is coaxially arranged on the inner side of the spool and integrally connects the lock base to the spool, and has a predetermined size in the pull-out direction in the lock base rotation restricted state by the lock means. A torsion shaft that torsionally deforms and allows rotation of the spool relative to the lock base when a rotational force of more than that is applied to the spool;
One end side is disposed on one side of the lock base and the spool and is movable together with either one, and the other end side is disposed on the other side of the lock base and the spool. Relative movement with respect to the other is made possible, and relative movement of the other end with respect to the other is restricted by the other after the spool rotates a predetermined amount in the pull-out direction with respect to the lock base. In addition, when the spool further rotates in the pull-out direction with respect to the lock base, the one end side is sequentially bent while being pulled out from the arrangement position on either one side to absorb energy. Members,
A webbing take-up device.   A rotating body that is coaxial with the spool and the lock base and is rotatable relative to the spool and the lock base is provided between the spool and the lock base. The rotating body passes through the other end of the elongated member. The webbing take-up device according to claim 1, wherein the webbing take-up device is supported.

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