JP2013249030A - Webbing winder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a twist frequency per unit length of a torsion shaft in a set force limiter load, even when arranging a lock part and a pretensioner mechanism via a spool.SOLUTION: In a webbing winder 10, when a spool is relatively rotated in the pulling-out direction to a lock base 52, one end of a trigger wire 76 slides on an inclined part 75 of a cam part 72, and the trigger wire 76 is moved to the other side in the axial direction of the spool. The trigger wire 76 presses a sub-torsion shaft 42, and the sub-torsion shaft 42 is moved to the other side in the axial direction of the spool. Thus, the sub-torsion shaft 42 and a lock ring of a switching mechanism are connected, and the force limiter load is set in a high load or a low load. Thus, on and after this, since rotation in the pulling-out direction of the spool is allowed in the force limiter load or more, the twist frequency per the unit length of the torsion shaft 34 can be secured.

Description

  The present invention relates to a webbing take-up device.

  In the retractor (webbing take-up device) for a seat belt described in Patent Document 1 below, a tread head (lock portion) is disposed on one side of the spindle (spool) in the axial direction, and a preload is provided on the other side of the spindle in the axial direction. A tensioner (pretensioner mechanism) is disposed. This has the advantage that the path of the load transmitted from the tread head and pretensioner to the spindle can be simplified.

  Further, a torsion bar (torsion shaft) is disposed inside the spindle, and the torsion bar includes a first shaft portion, a second shaft portion, and an intermediate portion connecting them. Yes. Then, the first shaft portion or the second shaft portion is torsionally deformed, so that the torque limiter load (force limiter load) becomes a low load or a high load, and the spindle is allowed to rotate above the torque limiter load.

JP 2011-105281 A

  However, in this seat belt retractor, one end of the torsion bar (end of the second shaft) is fixed to the tread head, and the other end of the torsion bar (end of the first shaft) is fixed to the spindle. Then, after the spindle rotates by a predetermined number by the first shaft portion being twisted and deformed, the intermediate portion is connected to the spindle and the second shaft portion is twisted and deformed. That is, after a predetermined number of rotations of the spindle with a torque limiter load set to a low load, the spindle is rotated a predetermined number of times with a torque limiter load set to a high load. For this reason, there exists a problem that the frequency | count of the twist per unit length of the torsion bar in the torque limiter load set to the low load or the high load is limited.

  In consideration of the above facts, the present invention provides a webbing winding capable of ensuring the number of twists per unit length of a torsion shaft at a set force limiter load even when a lock portion and a pretensioner mechanism are arranged via a spool. The purpose is to obtain a take-off device.

  The webbing take-up device according to claim 1, wherein the webbing is taken up by being rotated in the take-up direction, and the spool rotated in the draw-out direction by being pulled out, and an axial direction of the spool. A locking portion that is provided on a side and prevents rotation of the spool in the pull-out direction at least one of when the vehicle is suddenly decelerated and when the spool is suddenly rotated in the pull-out direction; A pretensioner mechanism that is operated in an emergency of the vehicle to rotate the spool in the winding direction, and is provided at a shaft center portion of the spool and is engaged with the spool so as to be integrally rotatable. A torsion shaft having a shaft portion and a second shaft portion and connecting the spool and the lock portion by the first shaft portion; and a pulling-out direction of the spool with respect to the lock portion A movement mechanism that moves the second shaft portion in the axial direction of the spool in conjunction with relative rotation of the second shaft portion, and a second mechanism that is coupled to the second shaft portion in conjunction with movement of the second shaft portion. And a switching mechanism that permits rotation of the second shaft portion in the pull-out direction when it is actuated.

  In the webbing take-up device according to claim 1, a torsion shaft is provided at an axial center portion of the spool, and the torsion shaft includes a first shaft portion and a second shaft portion engaged with the spool so as to be integrally rotatable. Have. Further, a lock portion is provided on one side in the axial direction of the spool, and a pretensioner mechanism is provided on the other side in the axial direction of the spool, and the spool and the lock portion are connected by the first shaft portion. For this reason, the rotation of the spool in the pull-out direction is prevented by preventing the lock portion from rotating in the pull-out direction at least one of when the vehicle is suddenly decelerated and when the spool is suddenly rotated in the pull-out direction. The

  Here, the moving mechanism moves the second shaft portion in the axial direction of the spool in conjunction with relative rotation in the pull-out direction with respect to the lock portion of the spool. For this reason, for example, when the first shaft portion connecting the lock portion and the spool is torsionally deformed in a state in which the lock portion is prevented from rotating in the pull-out direction, the spool is rotated relative to the lock portion. The second shaft portion is moved in the axial direction of the spool in conjunction with the rotation of the spool in the pull-out direction.

  Further, the switching mechanism is coupled to the second shaft portion in conjunction with the movement of the second shaft portion, and rotation of the second shaft portion in the pull-out direction is prevented. And the rotation to the extraction | drawer direction of a 2nd axial part is permitted by operating a switching mechanism.

  Thereby, for example, when the switching mechanism is set to be activated when the occupant's physique is less than the reference value, the pull-out direction of the first shaft portion and the second shaft portion when the occupant's physique is greater than the reference value. Rotation to is prevented. When the rotational force in the pulling-out direction of the spool exceeds the mechanical strength (torsional deformation load) of the first shaft portion and the second shaft portion, the first shaft portion and the second shaft portion are torsionally deformed. Therefore, the load that combines the torsional deformation load at the first shaft portion and the torsional deformation load at the second shaft portion is set as the force limiter load, and the force limiter load is set to a high load.

  On the other hand, for example, when the occupant's physique is less than the reference value, the switching mechanism is operated to permit rotation of the second shaft portion in the pull-out direction. That is, the second shaft portion is not twisted and deformed. When the rotational force in the pulling-out direction of the spool exceeds the mechanical strength (anti-twist deformation load) of the first shaft portion, the first shaft portion is twisted and deformed. Therefore, the torsional deformation load in the first shaft portion is set as the force limiter load, and the force limiter load is set to a low load.

  In this way, the force limiter load is immediately set to a high load or a low load in conjunction with the relative rotation of the spool and the lock portion. Thereafter, the spool is allowed to rotate in the pull-out direction with a force exceeding the set force limiter load. Therefore, even when the lock portion and the pretensioner mechanism are arranged via the spool, the number of twists per unit length of the torsion shaft at the set force limiter load can be secured.

  The webbing take-up device according to claim 2 is the webbing take-up device according to claim 1, wherein the first shaft portion and the second shaft portion are configured separately, and the first shaft portion. And the lock part are coupled so as to be integrally rotatable, and the moving mechanism is formed in the lock part, and has a slope part inclined toward the other side in the axial direction of the spool as it goes in the pull-out direction, A moving member extending in the spool so as to be movable in the axial direction of the spool and having one end abutting against the cam portion and the other end abutting against the second shaft portion. .

  In the webbing take-up device according to a second aspect, the first shaft portion and the second shaft portion are configured separately, and the first shaft portion and the lock portion are coupled to be integrally rotatable. For this reason, if the rotation of the lock portion is prevented in at least one of the time when the vehicle is suddenly decelerated and the spool is suddenly rotated in the pull-out direction, the spool is prevented from rotating in the pull-out direction. The When the rotational force in the pulling-out direction of the spool exceeds the mechanical strength (torsional deformation load) of the first shaft portion, the first shaft portion is twisted and deformed, and the spool is relative to the lock portion in the pulling direction. It is rotated.

Here, a cam portion is formed in the lock portion, and the cam portion has an inclined portion that is inclined toward the other side in the axial direction of the spool as it goes in the pull-out direction. A moving member extends in the spool, one end of the moving member is in contact with the cam portion, and the other end of the moving member is in contact with the second shaft portion.

  For this reason, when the spool is rotated relative to the lock portion in the pull-out direction, the moving member is rotated relative to the lock portion in the pull-out direction together with the spool, and one end of the moving member slides on the cam portion. Move. Then, when the one end portion of the moving member slides on the inclined portion, the moving member is moved to the other side in the axial direction of the spool. Accordingly, the second shaft portion is pressed by the moving member and moved to the other side in the axial direction of the spool.

  Therefore, by forming a cam portion in the lock portion and providing a moving member on the spool, the second shaft portion is moved to the other side in the axial direction of the spool in conjunction with relative rotation in the pull-out direction with respect to the lock portion of the spool. Therefore, the second shaft portion can be moved to the other side in the axial direction of the spool with a simple configuration.

  A webbing take-up device according to a third aspect is the webbing take-up device according to the first aspect, wherein the first shaft portion and the second shaft portion are configured integrally, and the moving mechanism A coupling portion formed at one end of one shaft portion and coupled to the lock portion so as to be relatively rotatable; and a coupled portion formed at the lock portion and screw-coupled to the coupling portion. Is rotated relative to the lock portion in the pull-out direction, the coupling portion moves to one side in the axial direction of the spool by screw coupling between the coupling portion and the coupled portion, and the coupled portion It is fastened so that it can rotate integrally with the part.

  In the webbing take-up device according to the third aspect, the first shaft portion and the second shaft portion are integrally formed. In addition, a coupling portion formed at one end of the first shaft portion is screw-coupled to a coupled portion formed in the lock portion. When the spool is rotated relative to the lock portion in the pull-out direction, the coupling portion moves to one side in the axial direction of the spool due to screw coupling between the coupling portion and the coupled portion, and is integrated with the coupled portion. Fastened to be rotatable.

  For this reason, when the vehicle suddenly decelerates and at least one of the time when the spool is suddenly rotated in the pull-out direction, the lock portion is prevented from rotating in the pull-out direction, and the spool is relative to the lock portion in the pull-out direction. When rotated, the first shaft portion and the second shaft portion are fastened together with the lock portion so as to rotate integrally with the spool while moving to one side (lock portion side) in the axial direction of the spool. Therefore, the second shaft portion can be easily moved to one side in the axial direction of the spool by screwing the first shaft portion and the lock portion.

  The webbing take-up device according to claim 4 is the webbing take-up device according to claim 1, wherein the first shaft portion and the second shaft portion are configured separately, and the first shaft portion. And the lock portion are coupled so as to be integrally rotatable, and the moving mechanism is provided in the spool so as to be movable in a direction perpendicular to the axis of the spool, and one side of the spool in the axial direction with respect to the orthogonal direction. Alternatively, a cam member having an inclined portion inclined to the other side, and a moving member that extends movably in the spool and has one end fixed to the lock portion and the other end locked to the cam member. And one end of the second shaft portion is in contact with the cam member.

  In the webbing take-up device according to a fourth aspect, the first shaft portion and the second shaft portion are configured separately, and the first shaft portion and the lock portion are coupled so as to be integrally rotatable. For this reason, if the rotation of the lock portion is prevented in at least one of the time when the vehicle is suddenly decelerated and the spool is suddenly rotated in the pull-out direction, the spool is prevented from rotating in the pull-out direction. The When the rotational force in the pulling-out direction of the spool exceeds the mechanical strength (torsional deformation load) of the first shaft portion, the first shaft portion is twisted and deformed, and the spool is relative to the lock portion in the pulling direction. It is rotated.

In addition, a moving member extends movably in the spool, and one end of the moving member is fixed to the lock portion. The other end of the moving member is locked to a cam member, and this cam member is in contact with one end of the second shaft portion.

  Here, the cam member is provided so as to be movable in a direction orthogonal to the axis of the spool, and has an inclined portion inclined toward one side or the other side of the spool in the axial direction with respect to the orthogonal direction. For this reason, the inclined portion is inclined to one side or the other side in the axial direction of the spool with respect to the moving direction of the cam member. As a result, when the spool is rotated relative to the lock portion in the pulling direction, the moving member is pulled out from the spool and the cam member is moved in a direction perpendicular to the axis of the spool. When the cam member is moved, one end portion of the second shaft portion slides on the inclined portion, so that the second shaft portion is moved in the axial direction of the spool.

  Therefore, by providing the moving member and the cam member, the second shaft portion can be moved in the axial direction of the spool in conjunction with the relative rotation in the pull-out direction with respect to the lock portion of the spool. The biaxial portion can be moved in the axial direction of the spool.

  The webbing take-up device according to claim 5 is the webbing take-up device according to any one of claims 1 to 4, wherein the webbing take-up device is provided on one side in the axial direction of the spool, and the vehicle is rapidly decelerated and A sensor mechanism that is actuated at least one time when the spool is suddenly rotated in the pull-out direction and prevents the spool from rotating in the pull-out direction by the lock portion is provided.

  In the webbing take-up device according to the fifth aspect, the sensor mechanism and the lock portion are provided on one side in the axial direction of the spool, and the pretensioner mechanism is provided on the other side in the axial direction of the spool. Thus, a webbing take-up device can be configured.

  According to the webbing take-up device of the first aspect, even when the lock portion and the pretensioner mechanism are arranged via the spool, the number of twists per unit length of the torsion shaft at the set force limiter load is obtained. It can be secured.

  According to the webbing retractor of the second aspect, the second shaft portion can be moved to the other side in the axial direction of the spool with a simple configuration.

  According to the webbing retractor of the third aspect, the second shaft portion can be easily moved to one side in the axial direction of the spool.

  According to the webbing retractor of the fourth aspect, the second shaft portion can be moved in the axial direction of the spool with a simple configuration.

  According to the webbing take-up device of the fifth aspect, the webbing take-up device can be configured by arranging the sensor mechanism, the lock portion, and the pretensioner mechanism in a balanced manner.

It is a disassembled perspective view which shows the torsion shaft and moving mechanism which are used for the webbing take-up device according to the first embodiment of the present invention. It is a disassembled perspective view which shows the principal part of the webbing winding device concerning a 1st embodiment of the present invention. FIG. 3 is a partially broken cross-sectional view showing a state before the sub-torsion shaft is moved in the webbing take-up device shown in FIG. 2. FIG. 4 is a partially broken cross-sectional view showing a state after the sub torsion shaft shown in FIG. 3 has been moved to the other axial side of the spool. (A) is explanatory drawing which shows the state by which the W pawl of the sensor mechanism shown by FIG. 2 is arrange | positioned in a standby position, (B) shows the state by which the W pawl was moved to the locking direction from the standby position. It is explanatory drawing. (A) is explanatory drawing which shows the state in the middle of the action | operation of the clutch of the switching mechanism shown by FIG. 2, (B) is explanatory drawing which shows the state which the action | operation of the clutch was completed. It is a disassembled perspective view which shows the switching mechanism part used for the webbing take-up device shown in FIG. It is a partially broken sectional view showing the state before the sub torsion shaft is moved in the webbing take-up device according to the second embodiment. FIG. 9 is a partially broken cross-sectional view showing a state after the torsion shaft shown in FIG. 8 has been moved to one side in the axial direction of the spool. It is the partially broken sectional view which shows the state before the subtorsion shaft is moved in the webbing winding device concerning a 3rd embodiment. FIG. 11 is a partially broken cross-sectional view showing a state after the sub torsion shaft shown in FIG. 10 has been moved to one side in the axial direction of the spool. It is a perspective view which shows the moving mechanism used for the webbing take-up device shown in FIG.

(First embodiment)

  Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 3, the webbing take-up device 10 according to the first embodiment of the present invention restrains a occupant's body, a frame 12, a substantially cylindrical spool 20 disposed inside the frame 12. Webbing 32 (see FIG. 2), a torsion shaft 34 disposed at the axial center of the spool 20, and a moving mechanism 70. Further, as shown in FIG. 2, a lock mechanism 50 and a sensor mechanism 80 are provided on one axial side of the spool 20 (arrow C direction side in FIG. 2 and the like). A pretensioner mechanism 110 and a switching mechanism 128 are provided on the arrow D direction side in FIG. Hereinafter, each configuration will be described.

  The frame 12 includes a plate-like back plate 14 that is fixed to the vehicle body. Leg pieces 16 and 18 extend substantially at right angles from both ends of the back plate 14 in the width direction, and the frame 12 is formed in a substantially concave shape in plan view. The leg plate 16 and the leg plate 18 are respectively formed with circular arrangement holes 16A and 18A (see FIG. 3), and ratchet teeth 16B (inner teeth) are formed on the entire inner peripheral portion of the arrangement hole 16A. Is formed.

  As shown in FIG. 3, the spool 20 is arranged coaxially with the arrangement holes 16 </ b> A and 18 </ b> A between the leg piece 16 and the leg piece 18, and a shaft accommodating portion 22 is provided in the axial center portion of the spool 20. It is formed through. A main torsion shaft 36 and a part of a sub torsion shaft 42, which will be described later, are inserted into the shaft housing portion 22, and the spool 20 rotates to the frame 12 through the main torsion shaft 36 and the sub torsion shaft 42. Supported as possible.

  In addition, a substantially annular first annular wall 24 is formed integrally with the spool 20 in the shaft accommodating portion 22 of the spool 20 at an intermediate portion in the axial direction of the spool 20. The inner peripheral portion of the first annular wall 24 is a main engaged portion 26, and the main engaged portion 26 is formed in a spline shape when the spool 20 is viewed in the axial direction. A substantially annular second annular wall 28 is formed integrally with the spool 20 in the shaft accommodating portion 22 of the spool 20 at a position on the leg piece 16 side. A pair of first support holes 24A and second support holes 28A for supporting a trigger wire 76 described later are formed through the first annular wall 24 and the second annular wall 28, respectively. The first support hole 24 </ b> A and the second support hole 28 </ b> A are formed in a circular cross section and are arranged in parallel with the axial direction of the spool 20.

  Further, the inner peripheral portion of the shaft accommodating portion 22 on the leg piece 18 side is a sub-engaged portion 30, and the sub-engaged portion 30 is formed in a spline shape when the spool 20 is viewed in the axial direction. .

  As shown in FIG. 2, the webbing 32 is formed in a long band shape, and one end portion (base end portion) in the longitudinal direction of the webbing 32 is connected and fixed to the spool 20. Then, when the spool 20 is rotated in the winding direction (the direction of arrow A in FIG. 2 and the like), the webbing 32 is wound in layers on the outer peripheral portion of the spool 20 from its own base end side, and the longitudinal direction of the webbing 32 By pulling the other end (tip) side, the spool 20 is rotated in the pulling direction (the direction of arrow B in FIG. 2 and the like), and the webbing 32 is pulled out from the spool 20.

[About torsion shaft 34]

  As shown in FIGS. 1 to 4, the torsion shaft 34 includes a main torsion shaft 36 as a “first shaft portion” and a sub-torsion shaft 42 as a “second shaft portion”. The main torsion shaft 36 and the sub torsion shaft 42 are configured separately.

  The main torsion shaft 36 is inserted into the shaft accommodating portion 22 of the spool 20 and is disposed coaxially with the spool 20. At one end of the main torsion shaft 36 (the end on the arrow C direction side in FIG. 1 or the like), a main coupling portion 38 is formed as a “coupling portion” coupled to a lock base 52 described later. The outer peripheral portion of the portion 38 is formed in a spline shape. Further, a main engagement portion 40 is formed at the other end of the main torsion shaft 36 (the end on the arrow D direction side in FIG. 1 and the like), and the outer periphery of the main engagement portion 40 is the aforementioned spool. Corresponding to the 20 main engaged portions 26, it is formed in a spline shape. The main engagement portion 40 is fitted into the main engaged portion 26, whereby the main torsion shaft 36 is coupled to the spool 20 so as to be integrally rotatable. Further, a portion between the main engaging portion 40 and the main coupling portion 38 is a main energy absorbing portion 36A, and the main energy absorbing portion 36A has a shaft shape with a circular cross section.

  The sub torsion shaft 42 is disposed on the other side in the axial direction of the spool 20 of the main torsion shaft 36 and is disposed coaxially with the main torsion shaft 36. A sub engagement portion 44 is formed at one end of the sub torsion shaft 42 (the end on the arrow C direction side in FIG. 1 and the like). The outer peripheral portion of the sub engaging portion 44 is formed in a spline shape corresponding to the sub engaged portion 30 of the spool 20, and a plurality of engaging teeth 44 </ b> A are formed on the outer peripheral portion of the sub engaging portion 44. ing. The sub engaging portion 44 is movably inserted into the sub engaged portion 30 and is engaged with the sub engaged portion 30 so as to be integrally rotatable. Thereby, the sub torsion shaft 42 is configured to be rotatable integrally with the spool 20 and to be movable in the axial direction of the spool 20 (the arrow C direction and the arrow D direction in FIG. 1 and the like).

  The other end portion (the end portion on the arrow D direction side in FIG. 1 and the like) of the sub torsion shaft 42 is formed with a sub fitting portion 46 that is fitted to a sleeve 138 of the clutch 130 described later. The outer peripheral part of the part 46 is formed in a spline shape. Further, a portion between the sub engagement portion 44 and the sub fitting portion 46 is a sub energy absorbing portion 42A, and the sub energy absorbing portion 42A has a circular shaft shape in cross section. A shaft portion 48 for supporting a trigger plate 132 of a switching mechanism 128 described later is formed on a portion of the sub fitting portion 46 opposite to the sub energy absorbing portion 42A. The shaft portion 48 is a circular shape. It is formed in a columnar shape and is arranged coaxially with the sub-torsion shaft 42.

  As shown in FIG. 3, a biasing spring 33 is provided on the other side in the axial direction of the spool 20 of the sub-engaging portion 44. The biasing spring 33 is configured as a compression coil spring, and the sub energy absorbing portion 42 </ b> A is inserted into the biasing spring 33. One end of the biasing spring 33 is in contact with the sub-engaging portion 44, and the other end of the biasing spring 33 is in contact with a sleeve 112 of the pretensioner mechanism 110 described later. Accordingly, the sub torsion shaft 42 is urged toward the one axial direction side of the spool 20 by the urging spring 33 and is in contact with the annular wall 24 of the spool 20.

  Further, as will be described later, the main energy absorbing portion 36A and the sub energy absorbing portion 42A deform the torsional deformation of the main energy absorbing portion 36A and the sub energy absorbing portion 42A. It is configured to absorb. Furthermore, the mechanical strength in the main energy absorbing portion 36A is set higher than the mechanical strength in the sub energy absorbing portion 42A.

  [About the lock mechanism 50]

  As shown in FIG. 2, the lock mechanism 50 includes a lock base 52 as a “lock portion” and a lock plate 66, and is provided at the end of the spool 20 on the leg piece 16 side.

  As shown in FIG. 3, the lock base 52 includes a substantially disc-shaped base portion 54 and a substantially cylindrical tube portion 56 that protrudes from the center portion of the base portion 54 toward the spool 20. Yes. The cylindrical portion 56 is inserted into the shaft accommodating portion 22 of the spool 20 so as to be relatively rotatable. A coupled hole 58 as a “coupled portion” is formed in the axial center portion of the cylindrical portion 56. The inner peripheral portion of the coupled hole 58 is formed in a spline shape corresponding to the main coupling portion 38 of the main torsion shaft 36 described above, and the main coupling portion 38 is fitted into the coupled hole 58. . Thereby, the lock base 52 is coupled to the main torsion shaft 36 so as to be integrally rotatable.

  Further, the side surface of the leg piece 18 in the cylindrical portion 56 is a cam portion 72 constituting a part of a moving mechanism 70 described later (see FIG. 1).

  Further, a support shaft 60 is provided on the side surface of the base portion 54 opposite to the cylindrical portion 56. The support shaft 60 is formed in a columnar shape, and the spool 20 is separated from the shaft center portion of the base portion 54. It protrudes to the opposite side. As shown in FIG. 2, the base 54 is provided with a locking projection 62 for locking an end of a return spring 96 of the sensor mechanism 80 described later. The base portion 54 is formed with a moving groove 64 for accommodating a lock plate 66 described later, and the moving groove 64 is opened to the outside of the lock base 52 in the radial direction.

  The lock plate 66 is formed in a substantially triangular plate shape when viewed in the axial direction of the spool 20 and is movably disposed in the movement groove 64 of the lock base 52. A cylindrical guide protrusion 68 is integrally formed on the lock plate 66, and the guide protrusion 68 protrudes from the lock plate 66 to the side opposite to the spool 20. Further, ratchet teeth 66A are formed at one end of the lock plate 66, and the ratchet teeth 66A are moved to the frame 12 by moving the lock plate 66 in the moving groove 64 to the outside in the radial direction of the lock base 52. The ratchet teeth 16B are configured to mesh with each other.

[About moving mechanism 70]

  As shown in FIG. 1, the moving mechanism 70 includes a cam portion 72 formed on the above-described lock base 52 and a pair of trigger wires 76 as “moving members”.

  The cam portion 72 has a general surface 73, and the general surface 73 is disposed along a direction orthogonal to the axial direction of the spool 20. A pair of recesses 74 are formed on the outer peripheral portion of the general surface 73, and the recesses 74 are formed in a substantially V shape when viewed from the outside in the radial direction of the cylindrical portion 56. Open to the side. Thereby, a part of the inner peripheral surface of the recess 74 is inclined toward the other side in the axial direction of the spool 20 toward the pulling-out direction (the direction of arrow B in FIG. 1), and this inclined surface becomes the inclined portion 75. The inclined portion 75 and the general surface 73 are connected.

  The trigger wire 76 is formed in a substantially long rod shape, and is inserted movably into the first support hole 24A and the second support hole 28A of the spool 20 with the longitudinal direction parallel to the axial direction of the spool 20 ( (See FIG. 3). As a result, the trigger wire 76 can rotate integrally with the spool 20. The both ends of the trigger wire 76 in the longitudinal direction are substantially hemispherical, one end of the trigger wire 76 is disposed in the recess 74 of the lock base 52, and the other end of the trigger wire 76 is sub-torsioned. The shaft 42 is in contact with the engagement teeth 44A.

  [Sensor mechanism 80]

  As shown in FIG. 2, the sensor mechanism 80 includes a sensor holder 82, a V gear 88, and a W pawl 104, and is disposed outside the leg pieces 16 of the frame 12.

  The sensor holder 82 is formed in a concave shape opened to the leg piece 16 side, and is fixed to the leg piece 16. On the inner side of the sensor holder 82, ratchet teeth 84 (inner teeth) are formed in a ring shape (see FIGS. 5A and 5B), and the ratchet teeth 84 are engaging teeth of a W pawl 104 described later. Corresponding to 104A.

  A substantially cylindrical bush 86 is provided in the sensor holder 82. The bush 86 is disposed coaxially with the spool 20 and is rotatably supported by the sensor holder 82. And the front-end | tip part of the support shaft 60 of the lock base 52 is inserted in the bush 86, and, thereby, the lock base 52 (spool 20) is rotatably supported by the sensor holder 82.

  The V gear 88 is disposed between the lock base 52 and the sensor holder 82 described above, and is accommodated in the sensor holder 82. The V gear 88 is formed in a substantially disk shape, and a plurality of lock teeth 90 are formed on the outer periphery of the V gear 88. Further, a through hole 92 is formed in the shaft center portion of the V gear 88, and the support shaft 60 of the lock base 52 is passed through the through hole 92. As a result, the V gear 88 is rotatably supported by the support shaft 60.

  As shown in FIG. 5A, a locking projection 94 is provided on the side surface of the V gear 88 on the lock base 52 side. A return spring 96 is bridged between the locking protrusion 94 and the locking protrusion 62 of the lock base 52 described above. The return spring 96 is configured as a compression coil spring, and the V gear 88 is connected to the return spring 96. The lock base 52 is biased in the pull-out direction (the direction of arrow B in FIG. 5A).

  Further, a long guide groove (not shown) is formed on the side surface of the V gear 88 on the lock base 52 side, and the tip end portion of the guide protrusion 68 of the lock plate 66 is inserted into the guide groove. Has been. The guide protrusion 68 is locked to one end of the guide groove by the urging force of the return spring 96. This restricts the rotation of the V gear 88 in the pull-out direction relative to the lock base 52 by the return spring 96 at one end of the guide groove. Normally, the V gear 88 is integrated with the lock base 52 (spool 20). It is configured to be rotatable.

  Further, the V gear 88 is formed with an accommodating recess 98, and the accommodating recess 98 is opened toward the sensor holder 82 side. The accommodation recess 98 is provided with a columnar pawl support shaft 100 and a pawl stopper 102 having a substantially rectangular columnar shape at a position on the pulling direction side of the pawl support shaft 100.

  The W pawl 104 is formed in a substantially C-shaped plate shape when viewed from one axial direction side of the spool 20. The W pawl 104 is disposed in the housing recess 98 and is pivotally supported by the pawl support shaft 100 so as to be swingable.

  Further, a sensor spring 108 is provided in the housing recess 98, and the sensor spring 108 is configured by a leaf spring and bent into an L shape. One end of the sensor spring 108 in the longitudinal direction is locked to the W pawl 104, and the other end of the sensor spring 108 in the longitudinal direction is locked to the V gear 88. The sensor spring 108 pawls the W pawl 104. The support shaft 100 is biased to the drawing direction side around the shaft.

  Further, an engagement tooth 104A is formed at the other end (extraction direction side end) of the W pawl 104, and the engagement tooth 104A is brought into contact with the pawl stopper 102 by the urging force of the sensor spring 108 (hereinafter referred to as the following). This position is called “standby position”). Further, the W pawl 104 is swung around the pawl support shaft 100 in the locking direction (the direction of arrow F in FIG. 5A), so that the engaging teeth 104A are engaged with the ratchet teeth 84 of the sensor holder 82. Thus, the rotation in the pull-out direction of the V gear 88 is limited (see FIG. 5B). In this state, rotation of the V gear 88 in the winding direction is permitted. On the other hand, when the W pawl 104 is swung to the standby position side from the state shown in FIG. 5B, the engagement teeth 104A are separated from the ratchet teeth 84, and the rotation restriction of the V gear 88 in the pull-out direction is restricted. It is configured to be released.

  The sensor mechanism 80 includes a conventionally known acceleration sensor (not shown) at a position below the V gear 88. The acceleration sensor includes a sensor housing, a spherical ball disposed on the sensor housing, and a sensor lever that is in contact with the ball and is swingably provided on the sensor housing. Then, as the ball rolls on the sensor housing, the sensor lever is swung and engaged with the lock teeth 90 of the V gear 88. Thereby, also in this case, the rotation in the pull-out direction of the V gear 88 is limited (the rotation in the winding direction of the V gear 88 is permitted).

  Here, in a state where the spool 20 and the V gear 88 are rotated in the pulling direction, when the rotation of the V gear 88 in the pulling direction is restricted, the lock base 52 resists the urging force of the return spring 96. It is rotated relative to the V gear 88 in the drawing direction (the direction of arrow B in FIG. 5A). At this time, the guide protrusion 68 of the lock plate 66 is moved from one end of the guide groove of the V gear 88 to the other end, so that the lock plate 66 is moved radially outward of the lock base 52. Accordingly, the ratchet teeth 66A of the lock plate 66 are configured to mesh with the ratchet teeth 16B of the frame 12.

[About the pretensioner mechanism 110]

  As shown in FIG. 3, the pretensioner mechanism 110 includes a case 111, a sleeve 112, a clutch 114, a roller 122, and a piston 124 (see FIG. 2). It is arranged outside the piece 18. The case 111 has a concave shape opened to the leg piece 18 side of the frame 12 and is fixed to the leg piece 18.

  The sleeve 112 is formed in a substantially cylindrical shape and is arranged coaxially with the spool 20. An outer peripheral portion of the sleeve 112 on one side in the axial direction of the spool 20 is formed in a spline shape and is fitted into the sub engaged portion 30 of the spool 20. As a result, the sleeve 112 is fixed to the spool 20 so as to be integrally rotatable.

  A flange 112 </ b> A is formed on the outer peripheral portion of the sleeve 112 opposite to the spool 20, and the flange 112 </ b> A is disposed outside the leg piece 18. A flat knurling process is performed on the outer periphery of the flange 112A.

  The clutch 114 is formed in a substantially bottomed cylindrical shape opened to the leg piece 18 side, and is disposed coaxially with the spool 20 and is rotatably supported by the case 111. A circular insertion hole 114A is formed through the bottom wall of the clutch 114 at the axial center, and the sub energy absorbing portion 42A of the sub torsion shaft 42 is penetrated into the insertion hole 114A. A flange 112 </ b> A of the sleeve 112 is disposed inside the clutch 114.

  An annular pinion 116 is integrally provided on the bottom wall of the clutch 114 at a portion opposite to the leg piece 18. The pinion 116 is disposed coaxially with the clutch 114, and pinion teeth 118 are formed on the outer periphery of the pinion 116.

  As shown in FIG. 2, on the inner side of the clutch 114, three roller accommodating recesses 120 for accommodating rollers 122 to be described later are formed. The roller receiving recess 120 has an inner circumferential surface 120A that is curved in a substantially U shape and is opened toward the central axis of the clutch 114 when viewed from the leg piece 18 side, and is 120 ° in the circumferential direction of the clutch 114. Arranged and communicated with each other. A portion where the distance between the inner peripheral surface 120A and the flange 112A of the sleeve 112 is the maximum is a wide portion, and the inner peripheral surface 120A of the roller accommodating recess 120 extends from the wide portion toward the winding direction. The distance between the flange 112A and the flange 112A is set to be short. Further, a flat knurling process is applied to the inner peripheral surface of the roller receiving recess 120.

  The roller 122 is formed in a columnar shape, and is provided in each of the wide portions of the three roller receiving recesses 120 with the axial direction parallel to the axial direction of the spool 20. In addition, a flat knurling process is performed on the outer peripheral portion of the roller 122.

  The piston 124 is disposed below the pinion 116 of the clutch 114 and is inserted into a cylindrical cylinder (not shown) constituting the pretensioner mechanism 110. A rack 126 is formed on the piston 124, and the rack 126 is configured to be able to mesh with the pinion teeth 118 of the pinion 116. Further, a gas generator (not shown) is provided in the lower end portion of the cylinder, and this gas generator is electrically connected to a vehicle control device (not shown). When the gas generator is operated under the control of the control device, the gas generator generates gas and the gas is supplied into the cylinder, and the rack 126 of the piston 124 meshes with the pinion teeth 118 of the pinion 116. It is configured to be.

[About switching mechanism 128]

  The switching mechanism 128 includes a clutch 130 (see FIG. 2) and a switching mechanism unit 190 (see FIG. 7), and is disposed outside the leg piece 18 of the frame 12.

(About the clutch 130)

  As shown in FIG. 2, the clutch 130 includes a trigger plate 132 (which is an element grasped as a “locking member” in a broad sense), a sleeve 138, a clutch guide 146, a clutch base 164, and a clutch cover. 170, a pair of clutch plates 180, and a pair of clutch springs 184.

  The trigger plate 132 is formed in a substantially narrow plate shape in which a circular hole 134 is formed through the center portion. The shaft portion 48 of the sub torsion shaft 42 is inserted into the circular hole 134, whereby the trigger plate 132 is rotatably supported by the sub torsion shaft 42. Further, an E ring 186 is fitted to the tip of the shaft portion 48 of the sub torsion shaft 42, thereby suppressing the relative movement of the trigger plate 132 in the axial direction with respect to the sub torsion shaft 42. Further, both end portions in the longitudinal direction of the trigger plate 132 are bent toward the spool 20 side, and the bent portion serves as a locking portion 136.

  The sleeve 138 is formed in a substantially cylindrical shape, is disposed coaxially with the sub-torsion shaft 42, and is rotatably supported by the case 111. A through hole 140 is formed in the axial center portion of the sleeve 138, and the through hole 140 is formed in a spline shape corresponding to the sub fitting portion 46 of the sub torsion shaft 42 described above. And the sub fitting part 46 is inserted in this through-hole 140 so that the movement to an axial direction is possible. Thus, the sleeve 138 is fitted to the sub torsion shaft 42 so as to be integrally rotatable, and the sub torsion shaft 42 is configured to be movable relative to the sleeve 138 in the axial direction of the spool 20.

  Further, a portion on one side in the axial direction (the direction of arrow C in FIG. 2) of the sleeve 138 is configured as a fitting portion 142 having a hexagonal outer shape. The other side (arrow D direction side in FIG. 2) is configured as a support portion 144 having a circular outer shape.

  The clutch guide 146 is formed in an annular shape having a through hole 148 penetrating in the axial direction. The support portion 144 of the sleeve 138 is inserted into the through hole 148, whereby the clutch guide 146 is supported by the sleeve 138 so as to be relatively rotatable.

  As shown in FIG. 6A, a pair of spring accommodating portions 150 for accommodating a clutch spring 184 described later are formed at two positions in the circumferential direction of the clutch guide 146. The spring accommodating portions 150 are formed in a point-symmetrical manner with the center portion of the clutch guide 146 as the center, and the outer wall portion 152 and the inner wall portion 154 that extend in the circumferential direction of the clutch guide 146, respectively, and the clutch guide 146 extends in the radial direction and is formed in a substantially U shape having a connecting wall portion 156 that connects the outer wall portion 152 and each end portion of the inner wall portion 154.

  Further, the clutch guide 146 is formed with a pair of clutch plate housing portions 158 adjacent to the spring housing portions 150 for housing a clutch plate 180 described later. A first support wall 160 is formed in the clutch plate housing 158, and the first support wall 160 extends from the connecting wall 156 toward the side opposite to the inner wall 154. Further, the clutch plate housing portion 158 is formed with a second support wall portion 162, and the second support wall portion 162 is separated from the connection wall portion 156 on the side opposite to the outer wall portion 152 with respect to the connection wall portion 156. Are arranged.

  As shown in FIG. 2, the clutch base 164 includes an annular fitted portion 166 having a hexagonal shape. A fitting portion 142 of the sleeve 138 is fitted inside the fitted portion 166, whereby the clutch base 164 is fixed to the sleeve 138 so as to be integrally rotatable. Further, the clutch base 164 has a pair of locking portions 168, and each locking portion 168 protrudes outward from the fitted portion 166, and a base end portion of a clutch plate 180 described later. It is locked.

  The clutch cover 170 is formed in an annular shape having a through-hole 172 penetrating in the axial direction, is disposed coaxially with the sleeve 138, and is disposed opposite the clutch guide 146. A plurality (six in this embodiment) of engaging claws 174 are formed on the inner peripheral portion of the clutch cover 170, and the engaging claws 174 protrude radially inward of the clutch cover 170. Then, the fitting portions 142 of the sleeve 138 are inserted into the through holes 172, and the fitting claws 174 are fitted to the fitting portions 142, so that the clutch cover 170 can rotate integrally with the sleeve 138. It is fixed. Further, a cross claw 178, which will be described later, is engaged with the clutch guide 146 in the circumferential direction. The clutch guide 146 has an operation position shown in FIG. , Relative rotation between the non-actuated position shown in FIG. 6 (A) is possible.

  A pair of notches 176 are formed on the outer periphery of the clutch cover 170 so as to be opened radially outward as viewed from the axial direction. Further, the clutch cover 170 is formed with a pair of cross claws 178 at positions inside the notches 176. The pair of cross claws 178 are formed in a point-symmetric manner with the center portion of the clutch cover 170 as the center. Further, these cross claws 178 are bent in a crank shape when viewed from the radial direction of the clutch cover 170, and the front end side protrudes toward the clutch guide 146 side from the base end side.

  As shown in FIG. 6 (A), on the tip side of each cross claw 178, an inner projecting portion projecting radially inward of the clutch guide 146, an outer projecting portion projecting radially outward of the clutch guide 146, A circumferential protrusion projecting in the winding direction of the clutch guide 146 (arrow A direction in FIG. 6) is provided, and the tip side of each cross claw 178 has a cross shape when viewed from the axial direction of the clutch guide 146. Is formed.

  The clutch plate 180 is formed in a substantially fan-shaped plate shape, is accommodated in the clutch plate accommodating portion 158 of the clutch guide 146, and is covered with the clutch cover 170. A rotation shaft 182 is formed at the base end portion of the clutch plate 180. The rotation shaft 182 is formed in a columnar shape and protrudes toward the clutch cover 170. The rotating shaft 182 is inserted into a hole 171 formed in the clutch cover 170, whereby the clutch plate 180 is rotatably supported by the clutch cover 170. Further, a spur-shaped knurled tooth 180 </ b> A is formed at the tip of the clutch plate 180.

  Further, holes 147 and 173 are formed in the above-described clutch guide 146 and clutch cover 170, respectively. These holes 147 and 173 are formed so as to face each other in a state where the clutch guide 146 is disposed at the non-actuated position with respect to the clutch cover 170. The holes 147 and 173 include trigger plates. 132 locking portions 136 are respectively inserted. The clutch guide 146 is restricted in relative rotation with respect to the spool 20 and the clutch cover 170 in a state where the clutch guide 146 is disposed at the non-operating position (the clutch guide 146 is restrained at the non-operating position).

  Further, as described above, in the state where the clutch guide 146 is constrained to the non-operating position, the cross claws 178 of the clutch cover 170 are positioned in the vicinity of the openings in the spring accommodating portions 150 of the clutch guide 146. The circumferential protrusion of each cross claw 178 is inserted inside the clutch spring 184 from one axial end of the clutch spring 184 housed in each spring housing 150, and the inner protrusion of each cross claw 178. The part and the outer protrusion are in contact with one axial end of the clutch spring 184. As a result, one end of the clutch spring 184 in the axial direction is locked to each cross claw 178. Further, the other axial end of the clutch spring 184 is locked to the connecting wall portion 156 of the spring accommodating portion 150, whereby the clutch guide 146 is wound around the clutch cover 170 by the clutch spring 184. It is biased in the taking direction and biased toward the operating position.

  On the other hand, in the inoperative position, the clutch plate 180 is accommodated in the clutch plate accommodating portion 158 so that the knurled teeth 180A of the clutch plate 180 are accommodated inside the outer peripheral portion of the clutch guide 146.

(About the switching mechanism 190)

  As shown in FIG. 7, the switching mechanism 190 includes a body 192, a lock ring 200 (an element grasped as a “rotating body” in a broad sense), an FL pawl 204, a cylinder 214, a piston 216, And a gas generator 218.

  The body 192 is formed in a substantially box shape opened to the leg piece 18 side (arrow C direction side in FIG. 7), and is fixed to the outside of the leg piece 18. Further, the above-described clutch 130 is disposed in the body 192.

  In addition, a gas generator accommodating portion 194 for accommodating a gas generator 218 described later is provided on the upper portion of the body 192 at a portion opposite to the leg piece 18. The gas generator accommodating portion 194 is formed in a substantially bottomed cylindrical shape, and is disposed with the axial direction extending in the leg piece 18 and communicated with a cylinder 214 described later.

  The lock ring 200 is formed in a substantially annular plate shape and is disposed in the body 192. An annular groove (not shown) is formed on the side surface of the body 192 of the lock ring 200, and an annular convex portion formed on the body 192 is inserted into the groove, so that the lock ring 200 is mounted on the body. 192 is rotatably supported. The lock ring 200 is disposed coaxially with the clutch guide 146 on the outer peripheral side of the clutch guide 146 described above. Flat-knurled knurled teeth 200A are formed on the entire inner periphery of the lock ring 200, and the knurled teeth 200A are configured to mesh with the knurled teeth 180A of the clutch plate 180 described above. Further, an engaged portion 202 is formed on the outer peripheral portion of the lock ring 200, and the engaged portion 202 is opened to the outside in the radial direction of the lock ring 200 when viewed in the axial direction, and an FL pawl described later. 204 can be engaged.

  The FL pawl 204 is formed in a substantially plate shape and is accommodated in the body 192 above the lock ring 200. A pawl side shaft portion 206 having a substantially circular cross section is formed at the lower portion of the FL pawl 204, and the pawl side shaft portion 206 is rotatably supported by the body 192. The FL pawl 204 has a substantially L-shaped arm portion 208. A lock portion 210 is formed at the lower end of the arm portion 208, and the lock portion 210 is disposed in the engaged portion 202 of the lock ring 200 and is engaged with the lock ring 200. Further, a locking hole 212 having a circular cross section is formed through the lower portion of the arm portion 208. A shear pin (not shown) provided in the body 192 is inserted into the locking hole 212, whereby the rotation of the FL pawl 204 is restricted, and the rotation of the lock ring 200 is performed by the FL pawl 204. Is blocked. On the other hand, the rotational force acts on the FL pawl 204, and the FL pawl 204 breaks the shear pin of the body 192, whereby the engagement between the FL pawl 204 and the engaged portion 202 is released, and the lock ring 200 rotates. Is configured to be allowed.

  The cylinder 214 is formed in a substantially L-shaped cylindrical shape in plan view, and is accommodated in the body 192 at a position of the FL pawl 204 on the drawing direction side. The cylinder 214 is in communication with the gas generator housing 194.

  The piston 216 is formed in a substantially rectangular parallelepiped shape, and one end portion of the piston 216 is disposed on the side of the upper end portion 209 of the arm portion 208 of the FL pawl 204. The other end of the piston 216 is inserted into the cylinder 214, and is configured such that the piston 216 is moved in the direction of arrow G in FIG. 7 by the operation of a gas generator 218 described later.

  The gas generator 218 is formed in a substantially cylindrical shape, and is disposed in the gas generator accommodating portion 194 of the body 192. The gas generator 218 is electrically connected to a vehicle control device (not shown). When the gas generator 218 is operated under the control of the control device, the gas generator 218 generates gas and the gas is supplied into the cylinder 214, and the piston 216 is moved to the upper end 209 side of the FL pawl 204. Configured to be moved to.

  Further, the control device is electrically connected to a collision detection means (not shown). The collision detection means predicts the collision of the vehicle by, for example, an acceleration sensor that detects the acceleration (particularly sudden deceleration) of the vehicle, a distance sensor that detects the distance to the obstacle ahead of the vehicle, and the like. In addition, the acceleration sensor detects a collision acceleration that is equal to or greater than a predetermined reference value, so that the collision detection means detects that the vehicle has collided. In this case, the pretensioner is controlled by the control device. The gas generator of mechanism 110 is configured to be activated.

  Further, the control device is electrically connected to a physique detection unit (not shown), and the physique detection unit detects the physique of the occupant seated on the seat by, for example, a load sensor, a belt sensor, a seat position sensor, or the like. It has become. Specifically, the load sensor detects the load acting on the vehicle seat, and the physique detection means detects the occupant's physique based on the detected load. The belt sensor detects the amount of webbing 32 pulled out from the spool 20, and the physique detection means detects the occupant's physique based on the detected amount of withdrawal. Further, the seat position sensor is configured by a position detection sensor that detects a sliding position of the vehicle seat in the front-rear direction and a camera sensor provided in the passenger compartment, and the physique is determined by the position of the seat detected by the seat position sensor. The detecting means detects the occupant's physique.

  The control device determines that the occupant's physique is less than a predetermined reference value based on the signal from the physique detection means, and determines that the vehicle has collided based on the signal from the collision detection means. In this case, the gas generator 218 of the switching mechanism 128 and the gas generator of the pretensioner mechanism 110 are operated by the control device.

  Next, functions and effects in the first embodiment will be described.

  First, by pulling the front end side of the webbing 32, the webbing 32 is pulled out from the spool 20 and attached to the occupant's body.

[About operation of lock mechanism 50]

  With the webbing 32 mounted on the occupant's body, for example, when the vehicle suddenly decelerates and the ball of the acceleration sensor of the sensor mechanism 80 rolls on the sensor housing, the sensor lever is swung. As a result, the sensor lever is engaged with the lock teeth 90 of the V gear 88 and the rotation of the V gear 88 in the pull-out direction is limited.

  Further, in a state where the webbing 32 is mounted on the occupant's body, the spool 20 (the main torsion shaft 36 and the sub-torsion shaft 36 and the sub When the torsion shaft 42 (including the torsion shaft 42) is suddenly rotated in the pull-out direction, the V gear 88 is rapidly rotated in the pull-out direction together with the W pawl 104. At this time, the W pawl 104 tries to stay in its position without rotating with respect to the V gear 88 due to the inertial force, and is relatively locked to the V gear 88 against the biasing force of the sensor spring 108. It is swung in the direction of arrow F in FIG. As a result, the engagement teeth 104A of the W pawl 104 are engaged with the ratchet teeth 84 of the sensor holder 82 (as shown in FIG. 5B), thereby restricting the rotation of the V gear 88 in the pull-out direction. The

  As described above, when the rotation of the V gear 88 in the pull-out direction is restricted at the time of sudden deceleration of the vehicle and at least one of the time when the spool 20 suddenly rotates in the pull-out direction, the lock base 52 (spool 20) returns. The spring 96 is rotated relative to the V gear 88 in the pull-out direction against the urging force of the spring 96. That is, the V gear 88 is rotated relative to the lock base 52 in the winding direction.

  When the lock base 52 (spool 20) is rotated relative to the V gear 88 in the pull-out direction, the guide protrusion 68 of the lock plate 66 is moved from one end of the guide groove of the V gear 88 to the other end. Is moved radially outward of the lock base 52. Therefore, the ratchet teeth 66 </ b> A of the lock plate 66 are engaged with the ratchet teeth 16 </ b> B of the frame 12. This prevents the lock base 52 and the spool 20 from rotating in the pull-out direction. Accordingly, the pulling out of the webbing 32 from the spool 20 is restricted, and the occupant's body trying to move forward of the vehicle is restrained by the webbing 32.

  As described above, when the vehicle is suddenly decelerated or when the spool 20 is suddenly rotated in the pull-out direction, the lock mechanism 50 is actuated to restrain the occupant's body.

  [Operation of the pretensioner mechanism 110]

  When the collision detection means detects that the vehicle has collided (when the vehicle is in an emergency), the pretensioner mechanism 110 is operated by the vehicle control device. Then, when the gas generator of the pretensioner mechanism 110 generates gas, the gas is supplied into the cylinder of the pretensioner mechanism 110. As a result, the piston 124 moves in the cylinder and the rack 126 of the piston 124 meshes with the pinion teeth 118 of the pinion 116, whereby the pinion 116 and the clutch 114 are rotated in the winding direction.

  When the clutch 114 is rotated in the winding direction, the roller 122 disposed in the roller housing recess 120 of the clutch 114 is moved from the wide portion to the circumferential direction of the clutch 114, and the inner circumferential surface 120A of the roller housing recess 120 The sleeve 112 is sandwiched between the flange 112A and the flange 112A. Since the outer peripheral surface of the roller 122, the inner peripheral surface of the roller accommodating recess 120, and the outer peripheral surface of the flange 112A are all subjected to flat knurling, they are in meshing state. Thereby, the clutch 114 and the spool 20 are connected, and the spool 20 is rotated in the winding direction. Accordingly, the webbing 32 is wound around the spool 20 and the occupant's body is restrained by the webbing 32.

[Operation of switching mechanism 128]

  In a state where the lock base 52 is prevented from rotating in the pull-out direction, the occupant's body trying to move forward is restrained by the webbing 32. In this state, when the occupant's body pulls the webbing 32 with a greater force, and the rotational force of the spool 20 in the pull-out direction exceeds the torsional load (deformation load) of the main energy absorbing portion 36A of the main torsion shaft 36, The main energy absorbing portion 36A is torsionally deformed, and the spool 20 is rotated relative to the lock base 52 in the pull-out direction.

  Here, the sub engagement portion 44 of the sub torsion shaft 42 is engaged with the spool 20 so as to be rotatable together and movable in the axial direction of the spool 20. A concave portion 74 is formed in the cam portion 72 of the lock base 52, and a part of the inner peripheral portion of the concave portion 74 is configured as an inclined portion 75. The inclined portion 75 of the spool 20 moves toward the pulling direction. It is inclined to the other side in the axial direction. Furthermore, one end portion of the trigger wire 76 is accommodated in the recess 74, and the other end portion of the trigger wire 76 is in contact with the engagement teeth 44 </ b> A in the sub engagement portion 44 of the sub torsion shaft 42.

  Thus, when the spool 20 is rotated relative to the lock base 52 in the pull-out direction, the trigger wire 76 is rotated relative to the recess 74 (lock base 52) in the pull-out direction together with the spool 20. Then, one end portion of the trigger wire 76 slides on the inclined portion 75 and is moved from the inclined portion 75 to the general surface 73, whereby the trigger wire 76 is moved to the other side in the axial direction of the spool 20 (FIG. 3). (See arrow D direction).

  When the trigger wire 76 is moved to the other side in the axial direction of the spool 20, the other end portion of the trigger wire 76 presses the engagement teeth 44 </ b> A of the sub-torsion shaft 42, and the sub-torsion shaft 42 is moved in the axial direction of the spool 20. Moved to the side. In this way, in conjunction with the relative rotation of the spool 20 in the pull-out direction with respect to the lock base 52, the sub-torsion shaft 42 is moved to the other side in the axial direction of the spool 20 (see FIG. 4).

  When the sub torsion shaft 42 is moved to the other side in the axial direction of the spool 20, the trigger plate 132 (locking portion 136) of the clutch 130 is moved to the other side in the axial direction of the spool 20 together with the sub torsion shaft 42. The locking part 136 is pulled out from the hole 173 of the clutch cover 170. As a result, the state where the relative rotation of the clutch guide 146 with respect to the clutch cover 170 is prevented in conjunction with the movement of the sub torsion shaft 42.

  When the state in which the relative rotation of the clutch guide 146 with respect to the clutch cover 170 is canceled, the clutch guide 146 is rotated from the non-operating position to the operating position by the urging force of the clutch spring 184, and the leading end of the clutch plate 180 is connected. The wall portion 156 is pressed (guided) in the tangential direction of the clutch guide 146. As a result, the clutch plate 180 is rotated toward the lock ring 200 (see arrow G in FIG. 6A), and the knurled teeth 180A of the clutch plate 180 mesh with the knurled teeth 200A of the lock ring 200 (FIG. 6 ( B) State shown. Therefore, since the clutch plate 180 and the lock ring 200 are coupled (the sub fitting portion 46 of the sub torsion shaft 42 and the lock ring 200 are coupled), the lock ring 200 is coupled to the clutch 130 (the sleeve 138, the clutch base). 164 and the clutch plate 180) to rotate in the pull-out direction.

  In addition, the vehicle control device determines whether the occupant's physique is equal to or greater than a predetermined reference value based on a signal from the physique detection means, and based on a signal from the collision detection means, It is determined whether or not. When the control device determines that the occupant's physique is equal to or greater than a predetermined reference value, the gas generator 218 of the switching mechanism 128 is not operated, so that the lock portion 210 and the lock ring 200 of the FL pawl 204 are not operated. The engaged state with the engaging portion 202 is maintained. For this reason, the rotation of the lock ring 200 in the pull-out direction is locked (blocked), so that the rotation of the clutch 130 in the pull-out direction is blocked. That is, the main coupling portion 38 (one end portion) of the main torsion shaft 36 and the sub fitting portion 46 (other end portion) of the sub torsion shaft 42 are prevented from rotating in the pull-out direction, and the main engagement of the main torsion shaft 36. A rotational force in the pulling direction from the spool 20 acts on the joint portion 40 (the other end portion) and the sub engagement portion 44 (one end portion) of the sub torsion shaft 42.

  The rotational force in the pull-out direction of the spool 20 causes the torsion resistant load (deformation resistant load) of the main energy absorbing portion 36A of the main torsion shaft 36 and the torsion resistant load (deformation resistant) of the sub energy absorbing portion 42A of the sub torsion shaft 42. When the sum exceeds the total load, rotation of the spool 20 in the pull-out direction is allowed due to twisting (deformation) of the main energy absorbing portion 36A and the sub energy absorbing portion 42A.

  Therefore, the torsional deformation of the main energy absorbing portion 36A and the sub energy absorbing portion 42A reduces the load (burden) on the chest of the occupant due to the webbing 32, and the torsional amount of the main energy absorbing portion 36A and the sub energy absorbing portion 42A. Only the kinetic energy of the occupant used for pulling the webbing 32 is absorbed.

  On the other hand, the control device determines that the occupant's physique is less than a predetermined reference value based on the signal from the physique detection means, and determines that the vehicle has collided based on the signal from the collision detection means. In this case, the gas generator 218 of the switching mechanism 128 is operated under the control of the control device.

  When the gas generator 218 is activated, gas is supplied from the gas generator 218 into the cylinder 214. When gas is supplied into the cylinder 214, the piston 216 moves to the arm portion 208 side of the FL pawl 204. As a result, the piston 216 presses the arm portion 208 of the FL pawl 204, so that rotational force acts on the FL pawl 204. By this turning force, the inner peripheral portion of the locking hole 212 of the FL pawl 204 breaks the shear pin of the body 192, thereby allowing the FL pawl 204 to rotate, and the engagement between the FL pawl 204 and the lock ring 200. The match is released. As a result, rotation of the lock ring 200 and the clutch 130 in the pull-out direction is permitted. That is, even if a rotational force in the pulling direction from the spool 20 acts on the sub engaging portion 44 of the sub torsion shaft 42, the sub energy absorbing portion 42A does not twist and deform.

  When the rotational force in the pulling direction of the spool 20 exceeds the torsion resistant load (deformation resistant load) of the main energy absorbing portion 36A, the spool 20 rotates in the pulling direction due to the twist (deformation) of the main energy absorbing portion 36A. Is acceptable.

  Accordingly, the torsional deformation of the main energy absorbing portion 36A reduces the load (burden) on the chest of the occupant due to the webbing 32, and the occupant's motion is used to pull the webbing 32 by the amount of torsion of the main energy absorbing portion 36A. Energy is absorbed.

  As described above, when the occupant's physique is equal to or greater than a predetermined reference value, the force limiter load is made the sum of the torsion resistant load of the main energy absorbing portion 36A and the torsion resistant load of the sub energy absorbing portion 42A. The load value of the limiter load is increased. On the other hand, when the occupant's physique is less than a predetermined reference value and a vehicle collision is detected, the force limiter load is made the torsion resistant load of the main energy absorbing portion 36A, and the load limiter load value Is reduced to a low load.

  Therefore, even when the lock base 52 (lock mechanism 50) and the pretensioner mechanism 110 are arranged via the spool 20, the force limiter load is immediately increased to a high load or low in conjunction with the relative rotation of the spool 20 and the lock base 52. Set to load. Thereafter, the spool 20 is allowed to rotate in the pull-out direction at a set force limiter load or more. Thereby, the number of twists per unit length of the torsion shaft 34 in the set force limiter load can be secured.

  Moreover, since the sub fitting portion 46 of the sub torsion shaft 42 and the lock ring 200 of the switching mechanism 128 can be connected by utilizing the movement of the sub torsion shaft 42 in the axial direction of the spool 20, the switching mechanism 128 is connected to the pretensioner. It can be easily placed outside the mechanism 110.

  Further, the force limiter load is set to a high load until the gas generator 218 of the switching mechanism 128 is operated. For this reason, even if the gas generator 218 is not operated due to damage of the gas generator 218 or the like, since the force limiter load is set to a high load, the protection performance (fail sale) for the occupant at the time of collision can be improved.

  Further, the cam portion 72 is formed on the lock base 52 and the trigger wire 76 is provided on the spool 20, whereby the sub torsion shaft 42 can be moved to the other side in the axial direction of the spool 20. For this reason, the sub torsion shaft 42 can be moved in the axial direction of the spool 20 with a simple configuration.

  Further, the lock mechanism 50 and the sensor mechanism 80 are disposed on one side in the axial direction of the spool 20, and the pretensioner mechanism 110 is disposed on the other side in the axial direction of the spool 20. For this reason, the webbing retractor 10 can be configured by arranging the lock mechanism 50, the sensor mechanism 80, and the pretensioner mechanism 110 in a well-balanced manner.

(Second Embodiment)

  8 and 9 show a simplified cross-sectional view of a webbing take-up device 300 according to a second embodiment of the present invention, partly broken. The webbing take-up device 300 in the second embodiment is configured in substantially the same manner as the webbing take-up device 10 in the first embodiment, but differs in the following points.

  In the torsion shaft 34, the main engagement portion 40 and the sub fitting portion 46 are integrated into a shaft engagement portion 302. That is, the main torsion shaft 36 and the sub torsion shaft 42 are integrally formed. The shaft engaging portion 302 is engaged with the main engaged portion 26 of the spool 20 so as to be integrally rotatable and relatively rotatable in the axial direction of the spool 20.

  In the moving mechanism 70, the cam part 72 and the trigger wire 76 are omitted. Further, the main coupling portion 38 of the torsion shaft 34 constitutes a part of the moving mechanism 70, and a plurality of helical external teeth are formed on the outer peripheral portion of the main coupling portion 38. Further, the coupled hole 58 of the lock base 52 constitutes a part of the moving mechanism 70, and a plurality of helical internal teeth are formed on the inner peripheral portion of the coupled hole 58. With the outer teeth of the main coupling portion 38 meshing with the inner teeth of the coupled hole 58 and the main coupled portion 38 being rotatable relative to the coupled hole 58, the main coupled portion 38 and the coupled hole 58 are It is connected (screw connection). Then, the main coupling portion 38 is rotated relative to the coupled hole 58 in the pull-out direction, so that the main coupling portion 38 (torsion shaft 34) is moved to the lock base 52 side (one axial direction side of the spool 20). Thus, the main coupling portion 38 (torsion shaft 34) and the coupled hole 58 (lock base 52) are configured to be fastened so as to be integrally rotatable in the pull-out direction.

  Further, a spring accommodating recess 304 is formed on the bottom surface of the coupled hole 58, and an urging spring 33 is provided in the spring accommodating recess 304. One end of the urging spring 33 is in contact with the bottom surface of the spring accommodating recess 304, and the other end of the urging spring 33 is in contact with the main coupling portion 38 of the torsion shaft 34, whereby the torsion shaft 34 is The biasing spring 33 biases the spool 20 to the other side in the axial direction.

  Further, a shear pin 306 for fixing the lock base 52 is integrally provided on an end surface of the spool 20 on the leg piece 16 side, and the shear pin 306 is formed in a column shape so that the spool 20 extends from the spool 20 to the leg piece 16 side. It is protruded to. Corresponding to the shear pin 306, a fitting recess 308 is formed on the side surface of the spool 20 of the base portion 54 of the lock base 52, and the fitting recess 308 is formed in a circular cross section and is opened to the spool 20 side. ing. A shear pin 306 of the spool 20 is fitted into the fitting recess 308, whereby the lock base 52 is fixed so as to rotate integrally with the spool 20. Further, the end of the spool 20 on the leg piece 18 side and the sleeve 112 are integrated, and a flange 112A protrudes from the spool 20.

  Furthermore, the trigger plate 132 in the switching mechanism 128 is fixed to the surface of the sub-fitting portion 46 on the spool 20 side, and the locking portion 136 of the trigger plate 132 is bent toward the opposite side of the spool 20. ing. The locking portion 136 is inserted into the hole 173 of the clutch cover 170 and the hole 147 of the clutch guide 146 from the clutch cover 170 side.

  In the webbing take-up device 300 configured as described above, since the shear pin 306 of the spool 20 is fitted in the fitting recess 308 of the lock base 52, the lock base 52 and the spool 20 are fixed so as to be integrally rotatable. Yes.

  When the lock base 52 is prevented from rotating in the pull-out direction, the spool 20 is prevented from rotating in the pull-out direction, and the body of the occupant trying to move forward of the vehicle is restrained by the webbing 32. In this state, when the occupant's body pulls the webbing 32 with a greater force, the load applied to the webbing 32 gradually increases, and the load applied to the webbing 32 increases until the shear pin 306 of the spool 20 is broken. Become.

  Further, when the rotational force of the spool 20 in the pull-out direction exceeds the mechanical strength of the shear pin 306 of the spool 20, the shear pin 306 is broken and the spool 20 and the torsion shaft 34 rotate relative to the lock base 52 in the pull-out direction. Is done.

  Here, helical outer teeth are formed on the outer peripheral portion of the main coupling portion 38 of the torsion shaft 34, and a helical shape is formed on the inner peripheral portion of the coupled hole 58 of the lock base 52. Internal teeth are formed. The main coupling portion 38 and the coupled hole 58 are screw-coupled in a state where the external teeth and the internal teeth mesh with each other. For this reason, when the torsion shaft 34 is rotated relative to the lock base 52 in the pull-out direction, the outer teeth of the main coupling portion 38 are moved along the inner teeth of the coupled hole 58, and thus the main coupling portion 38. Is relatively moved in the pull-out direction with respect to the coupled hole 58 and is relatively moved with respect to the coupled hole 58 toward one side in the axial direction of the spool 20 (arrow C direction side in FIG. 8). When the end surface of the main coupling portion 38 comes into contact with the bottom surface of the coupled hole 58, the torsion shaft 34 and the lock base 52 are coupled so as to be integrally rotatable in the pull-out direction.

  Further, when the torsion shaft 34 is moved to one side in the axial direction of the spool 20 (the lock base 52 side), the trigger plate 132 (locking portion 136) of the clutch 130 is moved to one side in the axial direction of the spool 20 together with the torsion shaft 34. As a result, the locking portion 136 is pulled out from the hole 147 of the clutch guide 146 (see FIG. 9). Thereby, the state of preventing the relative rotation of the clutch guide 146 with respect to the clutch cover 170 is canceled. Therefore, the sub-fitting portion 46 of the torsion shaft 34 is connected to the lock ring 200 by the clutch 130, and the subsequent operation is the same as in the first embodiment.

  As described above, also in the second embodiment, the same operations and effects as those in the first embodiment can be achieved.

  Further, as described above, the main torsion shaft 36 and the sub torsion shaft 42 are integrated, and the main torsion shaft 36 and the lock base 52 are screwed together, so that the sub torsion shaft 42 can be easily attached to the axial direction of the spool 20. Can be moved to one side.

  Moreover, since the external teeth formed in the main coupling portion 38 and the internal teeth formed in the coupled hole 58 are formed in a helical shape, the relative rotation amount of the torsion shaft 34 with respect to the lock base 52 is determined. The amount of movement of the torsion shaft 34 in the axial direction of the spool 20 can be increased. Thereby, in conjunction with the relative rotation of the spool 20 with respect to the lock base 52, the force limiter load can be immediately set to a high load or a low load.

  In the second embodiment, the main torsion shaft 36 and the sub torsion shaft 42 are integrally formed. Instead of this, the main torsion shaft 36 and the sub torsion shaft 42 may be formed separately, and both may be integrally formed by press fitting or the like. That is, “integral” in the present application means that the main torsion shaft 36 and the sub torsion shaft 42 are integrally formed, and that the main torsion shaft 36 and the sub torsion shaft 42 are formed as separate bodies. The integrated case is included.

(Third embodiment)

  10 and 11 show a webbing take-up device 400 according to a third embodiment of the present invention in a simplified sectional view with a part broken away. The webbing take-up device 400 in the third embodiment is configured in substantially the same manner as the webbing take-up device 10 in the first embodiment, but differs in the following points.

  In the spool 20, a wire groove portion 402 having a substantially semicircular cross section is formed on the end face on the leg piece 16 side. The wire groove portion 402 is opened toward the lock base 52 and is formed in an annular shape when viewed in the axial direction.

  Further, the spool 20 is formed with a wire accommodating portion 404 having a circular cross section for accommodating the trigger wire 76. The wire accommodating portion 404 communicates with the wire groove portion 402 and extends along the axial direction of the spool 20. The spool 20 extends to the front side of the side surface of the leg piece 18. Further, a cam accommodating portion 406 for accommodating a trigger cam 414 described later is formed inside the spool 20, and the cam accommodating portion 406 communicates with the wire accommodating portion 404.

  The sub engagement portion 44 of the sub torsion shaft 42 is formed with a smaller diameter than the sub engagement portion 44 in the first embodiment, and is inserted into the main engaged portion 26 of the spool 20. The sub-engaging portion 44 is engaged with the main engaged portion 26 so as to be integrally rotatable and movable in the axial direction of the spool 20.

  The urging spring 33 is disposed between the main engagement portion 40 of the main torsion shaft 36 and the sub engagement portion 44 of the sub torsion shaft 42 to urge the sub torsion shaft 42 toward the other axial direction of the spool 20. doing.

  A fixing recess 408 for fixing one end of the trigger wire 76 is formed in the base portion 54 of the lock base 52, and the fixing recess 408 is disposed coaxially with the wire accommodating portion 404. A through hole 410 is formed in the bottom wall of the fixed recess 408.

  The trigger wire 76 is inserted into the through hole 410 of the lock base 52 and extends into the wire accommodating portion 404 of the spool 20. Further, the end of the trigger wire 76 on the leg piece 18 side is bent inward in the radial direction of the spool 20 and is disposed in the cam housing portion 406 of the spool 20. A substantially cylindrical fixing pin 412 is integrally fixed to both longitudinal end portions of the trigger wire 76, and the fixing pin 412 at one end portion of the trigger wire 76 is fixed in the fixing recess 408.

  A trigger cam 414 serving as a “cam member” constituting the moving mechanism 70 is provided in the cam accommodating portion 406 of the spool 20. The trigger cam 414 is made of a substantially rectangular sheet metal, and is housed in the cam housing portion 406 so as to be movable in the radial direction of the spool 20 with the plate thickness direction as the axial direction of the spool 20. As shown in FIG. 12, the trigger cam 414 is formed in a substantially crank shape in a side view, and one end portion of the trigger cam 414 and the other end portion of the trigger cam 414 are connected by an inclined portion 416. One end portion of the trigger cam 414 is disposed on the other side in the axial direction of the spool 20 (the arrow D direction side in FIG. 12) than the other end portion, and the inclined portion 416 extends from one end portion of the trigger cam 414 to the other end portion. As it goes to, it is inclined to one side in the axial direction of the spool 20 (arrow C direction side in FIG. 12). A cam fixing portion 418 is integrally formed at one end of the trigger cam 414, and the cam fixing portion 418 is bent from one end of the trigger cam 414 toward one side in the axial direction of the spool 20. Thus, one end portion of the trigger cam 414 is formed in a concave shape opened to one side in the axial direction of the spool 20 in a side view, and this portion is a concave portion 74.

  An engagement groove 420 is formed in the trigger cam 414. The engagement groove 420 is formed in a substantially U shape when viewed from the axial direction of the spool 20 and extends from the other end of the trigger cam 414 to the recess 74. Has been. The sub energy absorbing portion 42 </ b> A of the sub torsion shaft 42 is inserted into the engagement groove 420, and the sub engagement portion 44 is disposed in the recess 74. In this state, the trigger cam 414 is brought into contact with the sub-engaging portion 44, and the cam fixing portion 418 is disposed on the radially outer side of the sub-engaging portion 44.

  Further, the cam fixing portion 418 is formed with a U-shaped locking groove 422 when viewed from the outside in the radial direction, and the locking groove 422 is opened to one side in the axial direction of the spool 20. The other end portion of the trigger wire 76 is inserted into the locking groove 422, and the fixing pin 412 at the other end portion of the trigger wire 76 is locked to the cam fixing portion 418.

  Further, as shown in FIGS. 10 and 12, the trigger plate 132 in the switching mechanism 128 is fixed to the side surface of the spool 20 of the sub-fitting portion 46, and the locking portion 136 of the trigger plate 132 is separated from the spool 20. It is bent toward the opposite side. The locking portion 136 is inserted into the hole 173 of the clutch cover 170 and the hole 147 of the clutch guide 146 from the clutch cover 170 side.

  In the webbing take-up device 400 configured as described above, when the lock base 52 is prevented from rotating in the pull-out direction, the spool 20 is prevented from rotating in the pull-out direction and tries to move forward in the vehicle. The body of the occupant is restrained by the webbing 32. In this state, when the rotational force in the pull-out direction of the spool 20 exceeds the torsion resistant load (deformation resistant load) of the main energy absorbing portion 36A of the main torsion shaft 36, the main energy absorbing portion 36A is torsionally deformed, and the spool 20 Is rotated relative to the lock base 52 in the pull-out direction. That is, the lock base 52 is rotated relative to the spool 20 in the winding direction.

  When the lock base 52 is rotated relative to the spool 20 in the winding direction, one end of the trigger wire 76 is rotated relative to the spool 20 in the winding direction. As a result, the trigger wire 76 is pulled out from the wire housing portion 404 while being squeezed into the opening of the wire housing portion 404 of the spool 20. Thereby, the other end part of the trigger wire 76 is moved.

  Since the other end portion of the trigger wire 76 is locked to the cam fixing portion 418 of the trigger cam 414, the trigger cam 414 is moved outward in the radial direction of the spool 20 as the trigger wire 76 moves. When the trigger cam 414 is moved outward in the radial direction of the spool 20, the sub engagement portion 44 (sub torsion shaft 42) is moved to one side in the axial direction of the spool 20 while sliding on the inclined portion 416.

  Further, when the sub torsion shaft 42 is moved to one axial direction side (the lock base 52 side) of the spool 20, the trigger plate 132 (locking portion 136) of the clutch 130 moves to one axial direction side together with the sub torsion shaft 42. Then, the locking portion 136 is pulled out from the hole portion 147 of the clutch guide 146. For this reason, the state of preventing the relative rotation of the clutch guide 146 with respect to the clutch cover 170 is eliminated.

  Thereby, the sub fitting portion 46 of the sub torsion shaft 42 is connected to the lock ring 200 by the clutch 130, and the subsequent operation is the same as in the first embodiment. As described above, also in the third embodiment, the same operations and effects as those in the first embodiment can be achieved.

  Further, by providing the trigger wire 76 and the trigger cam 414, the sub torsion shaft 42 can be moved to one side in the axial direction of the spool 20, so the sub torsion shaft 42 is moved to one side in the axial direction of the spool 20 with a simple configuration. Can be made.

  In the third embodiment, the recess 74 is formed so as to be recessed toward the other axial side of the spool 20. Instead of this, the recess 74 may be formed so as to be recessed toward the one axial side of the spool 20. In this case, the trigger cam 414 is disposed on one side in the axial direction of the sub engagement portion 44 of the sub torsion shaft 42, and the trigger plate 132 is attached to the spool 20 of the sub fitting portion 46 as in the first embodiment. It may be arranged on the other side in the axial direction.

  In the first to third embodiments, the ratchet teeth 66 </ b> A of the lock plate 66 of the lock mechanism 50 are configured to mesh with the ratchet teeth 16 </ b> B of the frame 12. Instead, for example, ratchet teeth (external teeth) are formed on the outer peripheral portion of the lock base 52, and at least one of the time when the vehicle is suddenly decelerated and when the spool 20 is suddenly rotated in the pull-out direction, You may comprise so that the pawl provided in the leg piece 16 may mesh | engage with the ratchet teeth of the lock base 52. FIG.

10 Webbing take-up device 20 Spool 34 Torsion shaft 36 Main torsion shaft (first shaft portion)
38 Main joint (joint)
42 Subtorsion shaft (second shaft)
52 Lock base (lock part)
58 Coupled hole (coupled part)
70 moving mechanism 72 cam portion 76 trigger wire (moving member)
80 Sensor mechanism 110 Pre-tensioner mechanism 128 Switching mechanism 200 Lock ring (rotating body)
300 Webbing Winder 400 Webbing Winder 414 Trigger Cam (Cam Member)

Claims (5)

The spool is rotated in the winding direction so that the webbing is wound up, and the webbing is pulled out and rotated in the pulling direction.
A locking portion that is provided on one side in the axial direction of the spool, and prevents rotation of the spool in the pull-out direction at least one of when the vehicle is suddenly decelerated and when the spool is suddenly rotated in the pull-out direction;
A pretensioner mechanism that is provided on the other axial side of the spool and is operated in an emergency of the vehicle to rotate the spool in the winding direction;
The first shaft portion and the second shaft portion, which are provided in the shaft center portion of the spool and are engaged with the spool so as to be integrally rotatable, and connect the spool and the lock portion by the first shaft portion. A torsion shaft,
A movement mechanism for moving the second shaft portion in the axial direction of the spool in conjunction with relative rotation in the pull-out direction of the spool with respect to the lock portion;
The second shaft portion is connected to the second shaft portion in conjunction with the movement of the second shaft portion to prevent the rotation of the second shaft portion in the pull-out direction and is operated to move the second shaft portion in the pull-out direction. A switching mechanism that allows rotation of
A webbing take-up device comprising: The first shaft portion and the second shaft portion are configured separately, and the first shaft portion and the lock portion are coupled so as to be integrally rotatable,
The moving mechanism is
A cam portion formed on the lock portion and having an inclined portion inclined toward the other side in the axial direction of the spool as it goes in the pull-out direction;
A moving member extending in the spool so as to be movable in the axial direction of the spool, having one end abutted against the cam portion and the other end abutted against the second shaft portion;
The webbing take-up device according to claim 1, comprising: The first shaft portion and the second shaft portion are integrally configured,
The moving mechanism is
A coupling portion formed at one end of the first shaft portion and coupled to the lock portion so as to be relatively rotatable;
A coupled portion formed on the locking portion and screw coupled to the coupling portion;
With
When the spool is rotated relative to the lock portion in the pull-out direction, the coupling portion moves to one side in the axial direction of the spool by screw coupling between the coupling portion and the coupled portion, and The webbing take-up device according to claim 1, wherein the webbing take-up device is fastened so as to be integrally rotatable with the coupled portion. The first shaft portion and the second shaft portion are configured separately, and the first shaft portion and the lock portion are coupled so as to be integrally rotatable,
The moving mechanism is
A cam member provided in the spool so as to be movable in a direction perpendicular to the axis of the spool and having an inclined portion inclined toward one side or the other side in the axial direction of the spool with respect to the orthogonal direction;
A movable member extending movably in the spool, one end of which is fixed to the lock portion and the other end is locked to the cam member;
With
The webbing take-up device according to claim 1, wherein one end portion of the second shaft portion is in contact with the cam member.   The spool is provided on one side in the axial direction, and is operated at least one of when the vehicle suddenly decelerates and when the spool is suddenly rotated in the pull-out direction to rotate the spool in the pull-out direction by the lock portion. The webbing take-up device according to any one of claims 1 to 4, further comprising a sensor mechanism for blocking.