JP4676345B2 - Webbing take-up device - Google Patents

Description

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

  A seat belt device that restrains the occupant's body with a long belt-like webbing belt includes a webbing take-up device. This webbing take-up device includes a spool. The spool is engaged with the base end side in the longitudinal direction of the webbing belt. When the spool is rotated in one winding direction around its axis, the webbing belt is wound and stored on the spool from the base end side.

  On the other hand, the webbing take-up device is provided with a lock mechanism for holding the body of an occupant trying to move substantially forward of the vehicle by locking the spool during sudden deceleration of the vehicle and regulating the withdrawal of the webbing belt. An example of a webbing take-up device provided with such a locking mechanism is disclosed in Patent Document 1 below.

  In the webbing take-up device disclosed in Patent Document 1, the lock ring is provided so as to be relatively rotatable coaxially with the spool. The lock plate is connected to the spool between the lock ring and the spool, and when the spool rotates relative to the lock ring in the pulling direction of the webbing belt, the lock plate is displaced outward in the rotation radius direction of the spool, and the frame It meshes with the internal tooth ratchet formed on the leg plate. This restricts the rotation of the spool when the spool is locked and the webbing belt is pulled out.

  Further, the lock wheel and the spool are connected by a torsion coil spring, and the lock wheel can rotate following the rotation of the spool by the urging force of the torsion coil spring.

  That is, in the normal drawing and winding of the webbing belt, the lock wheel rotates following the rotating spool. However, when the vehicle body suddenly decelerates, the occupant's body moves substantially to the front side of the vehicle, so that if the webbing belt is pulled out suddenly and the spool rotates suddenly in the pulling direction, the lock wheel cannot follow the spool. The spool rotates relative to the lock ring in the pull-out direction. As a result, as described above, the lock plate meshes with the ratchet of the leg plate, the spool is locked, and the webbing belt is restricted from being pulled out.

  In addition, the webbing take-up device is provided with a spiral spring that increases the urging force that urges the spool in the take-up direction as the spool rotates in the draw-out direction. The spool is rotated in the winding direction by the urging force of the spiral spring.

  Thus, even when the spool is rotating in the winding direction, the lock ring rotates following the spool. When the winding of the webbing belt onto the spool is completed by the urging force of the spiral spring and the spool stops, there is a possibility that the lock ring rotates in the winding direction due to inertia.

  Thus, the state in which the lock ring rotates in the winding direction with respect to the spool is the same as the state in which the spool rotates in the pull-out direction with respect to the lock ring. For this reason, even in such a state, the lock plate is displaced and meshes with the ratchet of the leg plate.

  In such a state, the so-called “end lock” state, the rotation of the spool in the pull-out direction is restricted, and the webbing belt wound around and stored in the spool cannot be pulled out.

  In the webbing take-up device disclosed in Patent Document 1, an end lock prevention mechanism is provided to prevent such problems.

The end lock prevention mechanism in Patent Document 1 includes a cam plate and a friction spring, and prevents end lock by preventing relative rotation between the lock wheel and the winding shaft at a predetermined time.
Japanese Utility Model Publication No. 62-95058

  However, the webbing take-up device provided with the conventional end lock preventing mechanism as described above has a configuration in which the cam plate is simply sandwiched between the friction springs. For this reason, when the spool rotates suddenly in the winding direction and winds up the webbing belt, the friction force is larger than the friction force between the friction spring and the cam plate when the friction spring holds the cam plate. As a result, the cam plate rotates, which may cause an end lock.

  An object of the present invention is to obtain a webbing take-up device that can prevent or effectively suppress the occurrence of an end lock when a spool that rotates in the take-up direction stops in consideration of the above facts.

In the webbing take-up device according to the first aspect of the present invention, the base end portion of the long belt-like webbing belt is locked, and the webbing belt is taken up by rotating in one winding direction around the axis. The spool is rotated in the pull-out direction opposite to the winding direction by pulling the webbing belt toward the tip side thereof, and can be relatively rotated coaxially with the spool. Provided on the rotating body so as to be displaceable between a position where the rotating body can be directly or indirectly engaged with the spool and a position where the engagement is released. In an indirectly engaged state, the spool rotates in the pull-out direction and the connecting member that rotates the rotating body in the pull-out direction, and the front is linked to the rotary body that rotates in the pull-out direction. A lock member that directly or indirectly engages the spool and restricts rotation of the spool in the pull-out direction, and operates in a sudden deceleration state of the vehicle to move the connecting member to the engageable position. Acceleration detecting means for rotating, a rotation detecting means for operating the rapid rotation of the spool in the pull-out direction to move the connecting member to the engageable position, and the webbing belt being wound around the spool. The regulating means that engages with the coupling member in a state where the coupling member is housed and regulates the displacement of the coupling member to the engageable position regardless of which of the acceleration detection means and the rotation detection means is activated. When, with a further moved, said connecting member by the operation by said acceleration detecting means is moved to said engageable position, the possible the engagement position by actuating the said rotation detecting means It is the same member and the connecting member canceller.

  In the webbing take-up device according to the first aspect of the present invention, when the webbing belt wound and accommodated in the spool is pulled toward the tip end, the spool is wound around the spool while rotating in the pull-out direction around the axis. The webbing belt being taken out is pulled out. When the webbing belt pulled out in this way is wound around the occupant's body, and further, for example, the tongue plate provided on the webbing belt is held by the buckle device provided on the side of the seat of the vehicle. The webbing belt is attached to the occupant's body, and the occupant's body is restrained by the webbing belt.

  In such a state, for example, when the traveling vehicle is suddenly decelerated, the acceleration detecting means is activated. The acceleration detecting means operates to displace the connecting member provided on the rotating body to a position where it can be directly or indirectly engaged with the spool.

  In the vehicle sudden deceleration state as described above, the occupant's body tends to inertially move toward the front side of the vehicle. When the occupant's body is about to move inertially toward the front side of the vehicle, the webbing belt hung around the occupant's body is pulled, thereby rotating the spool in the pull-out direction. In this state, when the connecting member is directly or indirectly connected to the spool as described above, the rotating body provided with the connecting member rotates in the pull-out direction together with the spool.

  When the rotating body rotates in the pull-out direction in this way, the lock member is interlocked, and the lock member is directly or indirectly engaged with the spool. By the direct or indirect engagement of the lock member with the spool, the rotation of the spool in the pull-out direction is restricted.

  By restricting the rotation of the spool in the pull-out direction in this way, further pulling out of the webbing belt from the spool is restricted, so that the occupant's body is reliably restrained by the webbing belt being wound around, The movement of the occupant's body to the front side of the vehicle is restricted by inertia during sudden deceleration of the vehicle.

  On the other hand, for example, when the vehicle decelerates, if the occupant's body is about to move inertially toward the front side of the vehicle suddenly, and the webbing belt hung around the occupant's body is pulled suddenly, the spool is pulled out rapidly. Rotate in the direction. Thus, when the spool is suddenly rotated in the pull-out direction, the rotation detecting means is activated. The rotation detecting means is actuated to displace the connecting member to a position where it can be directly or indirectly engaged with the spool.

  Thus, when the connecting member is connected to the spool, the rotating body rotates in the pulling direction together with the spool, and the lock member is directly or indirectly connected to the spool in conjunction with the rotation of the rotating body in the pulling direction. Engage. This restricts the rotation of the spool in the pull-out direction, and as described above, the occupant's body is reliably restrained by the webbing belt that is being laid around, and the occupant to the front side of the vehicle substantially due to inertia during sudden deceleration of the vehicle. Movement of the body is restricted.

  As described above, in the webbing take-up device according to the present invention, the connecting member is directly or indirectly engaged with the spool in both the sudden deceleration state of the vehicle and the state where the webbing belt is suddenly pulled out from the spool. By displacing in a possible direction, the lock member finally restricts rotation of the spool in the pull-out direction.

  Here, in a state where the webbing belt is wound around the spool and stored in the webbing take-up device according to the present invention, the restricting means engages with the connecting member. In this way, the connecting member engaged with the restricting means is restricted by the restricting means from being displaced in the direction of directly or indirectly engaging the spool.

  For this reason, when the webbing belt is wound around and stored in the spool, the connecting member does not engage with the spool. As a result, the spool rotates slightly in the pull-out direction in this state. Even if this happens, the rotating body does not rotate in the pull-out direction. Therefore, in this state, the lock member does not engage the spool, and the rotation of the spool in the pull-out direction is not restricted.

  Thereby, in the webbing take-up device according to the present invention, it is possible to effectively prevent the occurrence of so-called “end lock” in which the rotation of the spool in the pulling-out direction is restricted while the webbing belt is stored.

  Moreover, in the webbing take-up device according to the present invention, the rotation of the spool in the pulling-out direction can be restricted in each of the vehicle's rapid deceleration state and the state where the webbing belt is suddenly pulled out from the spool. In order to prevent this, it is only necessary to regulate the displacement of the connecting member. For this reason, the structure of the regulating means itself can be simplified.

  The webbing take-up device according to a second aspect of the present invention is the webbing take-up device according to the first aspect, wherein the rotation of the spool is transmitted at a reduced speed, and the webbing belt is pulled out from the spool. When rotating coaxially with respect to the spool by a predetermined angle of less than one rotation between the state and the entire storage state in which the webbing belt is wound and stored on the spool, the first rotating member, The connecting member that is provided integrally with the first rotating member and faces the connecting member on the displacement direction side of the connecting member to the engageable position in the fully retracted state, and to the engageable position. The restricting means is configured to include a restricting portion that restricts the displacement.

  In the webbing take-up device according to the second aspect of the present invention, for example, when the webbing belt is fully retracted with the entire amount of the webbing belt being wound on the spool, the webbing belt is pulled toward the leading end side, and the spool is rotated in the drawing direction. The rotation of the spool is transmitted to the first rotating member at a reduced speed, and the first rotating member rotates coaxially with the spool.

  In this way, when the webbing belt is pulled and the spool is rotated in the pulling-out direction, when the entire amount of the webbing belt is pulled out from the spool, the rotation start position from the above-described all-storage state is reached. The first rotating member rotates by a predetermined angle less than one rotation.

  Here, the first rotating member is provided with a restricting portion, and in the fully retracted state, the restricting portion faces the connecting member on the side where the connecting member is directly or indirectly engaged with the spool. As a result, the displacement of the restricting portion is restricted in the fully retracted state.

  By the way, like the first rotating member of the webbing take-up device according to the present invention, the rotation of the spool is transmitted at a reduced speed, and the webbing belt rotates at an angle of less than one rotation from the fully retracted state to the fully pulled out state. For example, when the webbing belt is fully pulled out, the locking member is always engaged with the spool, and until the webbing belt is fully retracted, the spool always rotates in the pulling direction regardless of the state of the vehicle. It is used in a mechanism that regulates

  For this reason, the increase in a substantial number of parts can be suppressed by diverting the 1st rotation member in the present invention with the member of such a mechanism, and it contributes to the overall weight reduction.

  A webbing take-up device according to a third aspect of the present invention is the webbing take-up device according to the first or second aspect of the present invention, which is linked to the rotation of the spool in the pull-out direction at a speed greater than a predetermined size. And an interlocking member that moves in a predetermined direction, moves along with the interlocking member, moves from an initial position to a position that can be engaged with the connecting member, engages the connecting member with the spool, and The rotation detecting means is configured to include an engaging member capable of eliminating movement associated with the interlocking member by reaching a position where the connecting member can be engaged.

  In the webbing take-up device according to claim 3, when the spool rotates in the pull-out direction at a speed greater than or equal to a predetermined size, the interlocking member moves in a predetermined direction in conjunction with the rotation of the spool, and further, the interlocking member Accordingly, the engaging member moves from the initial position toward a position where it can engage with the connecting member. In this way, the engaging member moves until it reaches a position where it can be engaged with the connecting member, so that the engaging member engages with the connecting member and the connecting member engages with the spool directly or indirectly. It is displaced to a possible position.

  Here, when the engaging member reaches a position where it can engage with the connecting member, the movement of the engaging member accompanying the interlocking member can be eliminated. For this reason, in a state where the engaging member has reached a position where it can engage with the connecting member, the engaging member can engage with the connecting member even if the interlocking member moves in conjunction with the rotation of the spool in the pull-out direction. There is no further movement from the position.

  According to a fourth aspect of the present invention, there is provided a webbing take-up device according to the first aspect of the present invention, wherein the spool rotates in the pull-out direction at a speed greater than or equal to a predetermined size. An engagement member that moves from a position to a position engageable with the connection member to engage the connection member with the spool, and biases the engagement member toward the initial position, to the engagement member The rotation detection means includes a return means for moving the engagement member to the initial position when transmission of the rotational force of the spool in the pull-out direction is canceled.

  In the webbing take-up device according to the fourth aspect, when the spool rotates in the pull-out direction at a speed equal to or greater than a predetermined size, the engaging member moves from the initial position to a position where it can engage with the connecting member. In this way, the engaging member moves until it reaches a position where it can be engaged with the connecting member, so that the engaging member engages with the connecting member and the connecting member engages with the spool directly or indirectly. It is displaced to a possible position.

  Here, the engaging member is urged toward the initial position by the return means. For this reason, when the transmission of the rotational force in the pulling-out direction of the spool to the engagement member is canceled in a state where the engagement member has reached the position where the engagement member can be engaged, the engagement member is biased by the return means. Thus, the engagement member is moved back to the initial position. Thus, when the engaging member returns to the initial position, the engagement of the engaging member with the connecting member is canceled, and the connecting member can be separated from a position where it can be directly or indirectly engaged with the spool. . Thereby, it can prevent that a connection member continues engaging with a spool carelessly.

  A webbing take-up device according to a fifth aspect of the present invention is the webbing take-up device according to the first or second aspect of the present invention, wherein the spool rotates when the spool rotates in the pull-out direction at a speed greater than a predetermined size. A second rotating member that is directly or indirectly connected to the spool and rotates, and an engagement that engages the connecting member with the spool by rotating from an initial position and reaching a position that can be engaged with the connecting member. A coupling member is coaxially attached to the second rotating member so as to be engageable with the engaging member, and the engaging member is turned into the connecting member by rotating in the pull-out direction together with the second rotating member. A third rotating member that is rotated to an engageable position and that can rotate relative to the second rotating member in a state where rotation is restricted, and the engaging member that is rotated in the pull-out direction from the initial position are Initial position And return means for rotating the engagement member to the initial position in a state where transmission of the rotational force in the pull-out direction from the third rotation member to the engagement member is eliminated. The rotation detecting means is configured.

  In the webbing take-up device according to claim 5, when the spool rotates in the pull-out direction at a speed greater than or equal to a predetermined size, the second rotating member is directly or indirectly connected to the spool, thereby rotating the spool. In response, the second rotating member rotates. A third rotating member is attached to the second rotating member. When the second rotating member rotates with the rotation of the spool in the pull-out direction, the third rotating member rotates together with the second rotating member, and further the third rotation. The member rotates the engaging member from the initial position to a position where it can engage with the connecting member. When the engaging member reaches an engageable position with respect to the connecting member and the engaging member engages with the connecting member, the engaging member is displaced to a position where the connecting member can be directly or indirectly engaged with the spool. Thus, the connecting member is engaged with the spool.

  Here, the third rotating member can be rotated relative to the second rotating member by being subjected to rotation restriction. For this reason, the engagement member is engaged with the connecting member to restrict the rotation of the engagement member. Further, in accordance with the rotation restriction of the engagement member, the rotation of the third rotation member is restricted. Even if the second rotating member rotates in response to the rotational force from the spool, the third rotating member does not rotate (that is, the third rotating member rotates relative to the second rotating member).

  Thus, in particular, the engaging member is moved from a position where it can be engaged with the connecting member without interrupting the rotation transmission of the spool from the spool to the second rotating member and from the second rotating member to the third rotating member. There is no rotation.

  On the other hand, in the webbing take-up device according to the present invention, the engaging member is biased toward the initial position by the return means. For this reason, when transmission of the rotational force of the spool in the pull-out direction via the second rotating member and the third rotating member is canceled in a state where the engaging member has reached a position where it can engage with the connecting member, The combined member is moved toward the initial position by the biasing force of the return means, and the engaging member returns to the initial position.

  Thus, when the engaging member returns to the initial position, the engagement of the engaging member with the connecting member is canceled, and the connecting member can be separated from a position where it can be directly or indirectly engaged with the spool. . Thereby, it can prevent that a connection member continues engaging with a spool carelessly.

  As described above, in the webbing take-up device according to the present invention, the mechanism for detecting either the sudden deceleration state of the vehicle or the state in which the webbing belt is suddenly pulled out of the spool is operated by the end lock. Generation can be prevented with an extremely simple configuration.

<Configuration of First Embodiment>
FIG. 4 is an exploded perspective view schematically showing the overall configuration of the webbing retractor 10 according to the first embodiment of the present invention. As shown in this figure, the webbing take-up device 10 includes a frame 12.

  The frame 12 includes, for example, a plate-like back plate 14 having a thickness direction substantially along the left-right direction of the vehicle, and the back plate 14 is, for example, near the lower end of the center pillar by fastening means such as bolts. The webbing take-up device 10 is attached to the vehicle body by being fixed to the vehicle body.

  From one end in the width direction of the back plate 14 substantially along the vehicle front-rear direction, a leg plate 16 is bent toward the inner side in the vehicle width direction (substantially vehicle left-right direction). A leg plate 18 is bent from the other end in the width direction of the back plate 14 in the same direction as the leg plate 16.

  A spool 24 is provided between the leg plate 16 and the leg plate 18. The spool 24 is formed in a substantially cylindrical shape in the axial direction along the opposing direction of the leg plate 16 and the leg plate 18. An insertion hole 26 is formed in the spool 24.

  Both ends of the insertion hole 26 are opened at the outer peripheral portion of the spool 24, and the shape of the opening is a long slit shape along the axial direction of the spool 24. The insertion hole 26 is formed so as to avoid a through hole 28 penetrating the axial center portion of the spool 24, and the longitudinal direction proximal end side of the long belt-like webbing belt 30 is formed from one opening end of the insertion hole 26. It is inserted.

  A cylindrical portion 32 penetrating in the width direction is formed at the longitudinal base end portion of the webbing belt 30, and a retaining shaft 34 is disposed inside the cylindrical portion 32 that has passed through the insertion hole 26. Thus, the base end side of the webbing belt 30 is prevented from coming out of the insertion hole 26 when the webbing belt 30 is pulled toward the distal end side.

  The webbing belt 30 thus prevented from coming off from the insertion hole 26 is wound around the outer periphery of the spool 24 in a layered manner from the base end side by rotating the spool 24 in one winding direction around its own axis. And stored.

  On the other hand, a rod-like torsion shaft 36 that is formed in the longitudinal direction along the axial direction of the spool 24 is disposed inside the through hole 28. The torsion shaft 36 is connected to the spool 24 in a state in which the torsion shaft 36 is stopped around the axis inside the spool 24 on the leg plate 18 side. Furthermore, the end of the torsion shaft 36 on the leg plate 18 side penetrates the leg plate 18 and protrudes outward of the frame 12.

  A spring cover 38 is disposed outside the leg plate 18. The spring cover 38 has a box shape that opens toward the leg plate 18, and the spring cover 38 is fixed to the leg plate 18 by fitting means such as screws or fitting claws formed on the spring cover 38 or the leg plate 18. Has been.

  A spiral spring 40 is accommodated inside the spring cover 38. The spiral spring 40 is a spring having a structure in which the urging force gradually increases when the inner end in the spiral direction is rotationally displaced in the pulling direction opposite to the winding direction with respect to the outer end in the spiral direction. Is locked to a spring seat 42 provided on the opening side of the spring cover 38 with respect to the spiral spring 40.

  The spring seat 42 is fixed to the spring cover 38, and the spiral direction outer end of the spiral spring 40 is connected to the leg plate 18 (frame 12) via the spring seat 42 and the spring cover 38. An adapter 44 is provided in the vicinity of the spiral direction inner end of the spiral spring 40.

  A spiral direction inner end of the spiral spring 40 is fixed to a part of the outer periphery of the adapter 44. Further, the end portion on the leg plate 18 side of the torsion shaft 36 penetrating the spring seat 42 is fitted and fixed to the axial center portion of the adapter 44.

  On the other hand, a pretensioner 50 is provided outside the leg plate 16. The pretensioner 50 includes a cylinder 52.

  In the present embodiment, the cylinder 52 is plastically deformed so that the cross-sectional shape is appropriately deformed while maintaining internal communication at, for example, a bent portion 54 set at an intermediate portion in the axial direction of a metal pipe. It is formed by bending appropriately. One side in the axial direction from the bent portion 54 is a mounting portion 56. A gas generator 58 is attached to the opening end of the attachment portion 56.

  The gas generator 58 is electrically or mechanically connected to an acceleration sensor (not shown). When the acceleration sensor detects an acceleration (deceleration) when the vehicle is suddenly decelerated, the gas generator 58 has an internal structure. The gas generating agent provided in is ignited. As a result, the gas generating agent is burned in an extremely short time to generate gas instantaneously.

  A side of the bent portion 54 opposite to the mounting portion 56 is a cylinder body 60. Although the bent portion 54 is bent by plastic deformation as described above, the internal communication is ensured, so that the gas generated by the gas generator 58 attached to the attachment portion 56 is directed to the bottom side of the cylinder body 60. Supplied. A piston 62 is provided inside the cylinder body 60.

  The piston 62 is formed in a disk shape whose outer diameter is substantially equal to (in a strict sense, slightly smaller) the inner diameter of the cylinder body 60. A cylindrical holding portion 64 is coaxially and integrally formed with the piston 62 on the end surface of the piston 62 facing the bottom side of the cylinder body 60. The holding portion 64 has an outer diameter smaller than that of the piston 62, and a sealing member 66 is fitted on the outer peripheral portion thereof.

  The sealing member 66 is formed in an annular shape and has elasticity, and is disposed on both the outer peripheral portion of the holding portion 64 and the inner peripheral portion of the cylinder main body 60 in a state where the piston 62 is disposed inside the cylinder main body 60. It is elastically pressed and seals between the holding portion 64 and the cylinder body 60. For this reason, when gas is supplied into the cylinder body 60 and the internal pressure of the cylinder body 60 increases, the piston 62 slides toward the upper end side of the cylinder body 60.

  A rack bar 68 as a slide member is formed on the side opposite to the holding portion 64 of the piston 62 (that is, the opening end side of the cylinder body 60). The rack bar 68 has a rectangular bar shape that is long along the opening direction of the cylinder main body 60, and a plurality of rack teeth are formed at regular intervals along the longitudinal direction of the rack bar 68 at one end in the width direction. .

  A gear case 70 as a support member is provided on the side of the leg plate 16 near the opening end of the cylinder body 60, and a cover plate 72 is provided on the opposite side of the gear case 70 via the cylinder body 60. .

  The cover plate 72 is formed in a box shape capable of covering the rack bar 68 protruding from the cylinder body 60 from the side opposite to the leg plate 16 of the cylinder body 60, and at least the rack bar 68 protruding from the opening end of the cylinder body 60. It is formed in a shape that does not interfere with. A plurality of fastening pieces 74 are formed on the outer peripheral portion of the cover plate 72, and these fastening pieces 74 are fastened and fixed to the leg plate 16 with screws 76, whereby the cover plate 72 is fixed to the frame 12. It has a structure.

  Further, the cover plate 72 is formed with a holding portion (not shown) into which the opening end of the cylinder body 60 and the vicinity thereof are fitted, whereby the cover plate 72 is connected to the cylinder body 60. A pinion 90 is disposed between the cover plate 72 and the gear case 70.

  The pinion 90 meshes with the rack teeth at the front end side of the rack bar 68 and is rotatably supported at the other end of the torsion shaft 36 that penetrates the leg plate 16 and the gear case 70. 90 is structured to rotate in the winding direction.

  A clutch 92 is provided on the leg plate 16 side of the pinion 90. Since the clutch 92 is rotatably supported by the torsion shaft 36, the clutch 92 does not rotate even if the torsion shaft 36 rotates. However, the clutch 92 is engaged with the pinion 90, and when the pinion 90 rotates in the winding direction, a part of the clutch 92 is deformed by this rotational force and is connected to the torsion shaft 36.

  A lock mechanism 120 is provided on the side of the leg plate 16. The lock mechanism 120 includes a sensor holder 122. The sensor holder 122 is formed in a concave shape partially opened toward the leg plate 16 side, and a part of the cover plate 72 is located inside the portion opened toward the leg plate 16 side.

  The sensor holder 122 has a cylindrical pin protruding from a predetermined portion of the outer peripheral portion toward the leg plate 16 and is inserted into a hole formed on the leg plate 16 side. The sensor holder 122 is fixed to the leg plate 16 by pressing.

  A sensor cover 124 is provided on the opposite side of the sensor holder 122 from the leg plate 16. The sensor cover 124 has fitting claws and the like formed on the outer periphery and the like, and is fitted to a predetermined portion of the sensor holder 122 and mechanically connected to the sensor holder 122. The sensor cover 124 is formed with a cylindrical bearing portion (not shown), and rotatably supports the other end portion of the torsion shaft 36 penetrating the sensor holder 122.

  A V gear 126 is provided between the sensor holder 122 and the sensor cover 124. The V gear 126 is formed in a shallow cylindrical shape (or a tray shape) opened toward the sensor cover 124 side, and ratchet teeth are formed on the outer peripheral portion thereof. A torsion shaft 36 passes through the V gear 126 and is attached to the torsion shaft 36 so as to be rotatable coaxially and integrally with the torsion shaft 36.

  As shown in FIG. 1 showing the configuration between the V gear 126 and the sensor cover 124 in FIG. 4, a rotation detection mechanism 127 as a rotation detection means is provided inside the V gear 126. The rotation detection mechanism 127 includes a gear ring 154. The gear ring 154 is formed in a coaxial ring shape with respect to the V gear 126, and is supported on a support portion provided on the V gear 126 so as to be coaxial with the V gear 126 and relatively rotatable.

  On the inner periphery of the gear ring 154, internal ratchet teeth are formed. A W pawl 134 is provided on the inner side of the gear ring 154 corresponding to the inner ratchet teeth of the gear ring 154.

  The W pawl 134 is pivotally supported by a pin formed on the V gear 126 at a position displaced with respect to the axis of the torsion shaft 36 so as to be swingable around an axis parallel to the torsion shaft 36.

  The W pawl 134 is structured to come in contact with and separate from the inner peripheral portion of the gear ring 154 by swinging, and meshes with ratchet teeth formed on the inner peripheral portion of the gear ring 154 by moving closer to the inner peripheral portion of the gear ring 154. . If the V gear 126 rotates in the pulling direction in this meshing state, the rotational force in the pulling direction of the V gear 126 is transmitted to the gear ring 154 via the W pawl 134, and the gear ring 154 is rotated in the pulling direction. .

The W pawl 134 is attached with a W mass 138 that constitutes a rotation detecting means together with the W pawl 134 as a weight. One end of the return spring 13 6 is engaged in the W pawl 134. The other end of the return spring 13 6 are engaged with the V gear 126, meshing portion between the inner periphery of the gear ring 154 in the direction (W-pawl 134 to release the engagement with the gear ring 154 from the inner periphery of the gear ring 154 The W pawl 134 is biased in the direction of separation.

  On the other hand, the gear ring 154 is provided with a friction spring 155 as an engaging member. The friction spring 155 includes a substantially ring-shaped main body 156. The main body 156 has an inner diameter that is substantially the same as or slightly smaller than the outer diameter of the gear ring 154, and the main body 156 is fitted into the outer periphery of the gear ring 154.

  The main body 156 can rotate relative to the gear ring 154 coaxially, but is pressed against the outer periphery of the gear ring 154 by an urging force, and an external force that prevents the integral rotation with the gear ring 154 is applied to the friction spring 155. As long as it does not act, the main body 156 (friction spring 155) rotates integrally with the gear ring 154.

  On the other hand, a sensor gear 128 as a rotating body is provided on the sensor cover 124 side of the V gear 126. A torsion shaft 36 passes through the main body 130 of the sensor gear 128 coaxially. A main body 130 of the sensor gear 128 is rotatably supported on the torsion shaft 36.

  One end of a return spring 132 is locked to a part of the sensor gear 128. The return spring 132 is a tension coil spring, and the other end is locked to the sensor cover 124. When the sensor gear 128 rotates around the torsion shaft 36 in the pull-out direction, the sensor gear 128 is biased in the winding direction. .

  Further, a long pressing portion 168 is formed on the main body 130 of the sensor gear 128 toward the V gear 126 side. A shaft 129 protrudes from the end of the pressing portion 168 opposite to the V gear 126, and the connecting claw 140 as a connecting member is around an axis parallel (in the same direction) as the axial direction of the torsion shaft 36. It is pivotally supported by the pressing portion 168 so as to be rotatable.

  The connecting claw 140 rotates to come in contact with and disengage from the outer peripheral portion of the V gear 126, and the V gear 126 rotates in the pull-out direction with the connecting claw 140 approaching and engaging with the outer peripheral portion of the V gear 126. If so, the rotation of the V gear 126 in the pull-out direction is transmitted to the sensor gear 128 via the connecting claw 140, and the sensor gear 128 rotates in the pull-out direction together with the V gear 126.

  Further, the main body 156 of the friction spring 155 is not formed in a complete ring shape because a part in the circumferential direction is interrupted, and has both ends in the circumferential direction. A pressing portion 158 bent in a substantially bowl shape is continuously formed from the circumferential end portion of the main body 156. The pressing portion 158 is formed corresponding to the connecting claw 140, and the tip of the pressing portion 158 is located on the radially outer side with respect to the main body 156.

  On the rotation locus of the pressing portion 158 when the main body 156 is rotated together with the gear ring 154, an engagement pin 141 that protrudes from the tip of the connecting claw 140 toward the opposite side of the V gear 126 is located. When the pressing portion 158 comes into contact with and presses the engagement pin 141 by the rotation of 156, the connecting claw 140 rotates so as to approach the outer peripheral portion of the V gear 126.

  Further, an acceleration sensor 142 as an acceleration detecting means shown in FIG. Corresponding to the acceleration sensor 142, the sensor holder 122 is formed with a box-shaped accommodation portion 144 that opens toward the sensor cover 124, and at least a part of the acceleration sensor 142 is accommodated in the accommodation portion 144.

  The acceleration sensor 142 includes a base 146. The base 146 is formed in a flat plate shape in the thickness direction in the vertical direction as a whole. A curved surface that opens upward is formed on the upper end surface of the base 146, and a hard ball 148 as an inertial body is disposed on the curved surface. A sensor claw 150 is provided above the hard ball 148.

  The sensor claw 150 is pivotally supported on the upper end of the vertical wall 152 erected upward from a part of the outer periphery of the base 146, and the hard ball 148 rolls on the curved surface of the base 146. Then, the sensor claw 150 is pushed up. When the sensor claw 150 is pushed up by the hard ball 148, the sensor claw 150 abuts on the connection claw 140 shown in FIG.

  The V gear 126 described above is positioned on the rotation direction side of the connecting claw 140 rotated by the engagement of the sensor claw 150, so that the connecting claw 140 meshes with the V gear 126.

  On the other hand, as shown in FIG. 4, the lock mechanism 120 includes a lock pawl 160 as a lock member. The lock pawl 160 includes a shaft 162. The shaft 162 is axially parallel to the axial direction of the spool 24 (same direction), and one end of the shaft 162 is pivotally supported by a bearing hole (not shown) formed in the leg plate 18. Yes.

  The other axial end portion of the shaft 162 is pivotally supported by a bearing hole 164 formed in the gear case 70. A pawl portion 166 is formed on the other axial end side of the shaft 162. The pawl portion 166 is a plate-like member in the thickness direction along the axial direction of the shaft 162, and external ratchet teeth are formed on a part of the outer periphery thereof.

  A lock base 170 is provided on the side of the pawl portion 166 along the rotational radius direction of the shaft 162. The lock base 170 includes a fitting insertion portion 171. The fitting insertion portion 171 is formed in a columnar shape, and is fitted into the other end portion of the through hole 28 of the spool 24 so as to be rotatable coaxially with the spool 24.

  The insertion portion 171 and thus the lock base 170 are coaxially penetrated with the torsion shaft 36 being prevented from rotating, and rotate coaxially and integrally with the torsion shaft 36.

  A ratchet portion 172 is integrally formed on the leg plate 16 side of the fitting insertion portion 171. The ratchet portion 172 is formed coaxially with the fitting insertion portion 171, and ratchet teeth are intermittently formed on the outer peripheral portion thereof.

  In the lock pawl 160, the ratchet teeth of the pawl portion 166 mesh with the ratchet teeth of the ratchet portion 172 as the shaft 162 rotates in the winding direction. In the meshed state of the pawl portion 166 and the ratchet portion 172, the rotation of the ratchet portion 172, and thus the lock base 170 in the pull-out direction is restricted.

  Further, the pawl portion 166 corresponds to the pressing portion 168 of the sensor gear 128 shown in FIG. 1, and when the main body 130 of the sensor gear 128 rotates in the pull-out direction, the pressing portion 168 presses the pawl portion 166, and the lock pawl. The structure is such that 160 is rotated in the winding direction.

  On the other hand, as shown in FIG. 1, on the side of the sensor gear 128 opposite to the V gear 126, a cam plate 173 constituting a restricting means is disposed as a rotating member. The cam plate 173 is formed in a substantially disc shape and is rotatably supported on the torsion shaft 36.

  A circular hole 174 is formed at a position displaced radially outward from the center of the cam plate 173, and a reduction gear 176 is rotatably supported around an axis parallel to the spool 24. The reduction gear 176 includes a gear portion 178. The gear portion 178 is an external spur gear and is located on the opposite side of the cam plate 173 from the sensor gear 128. A gear 180 is provided on the tip side of the torsion shaft 36 corresponding to the gear portion 178. The gear 180 has fewer teeth than the gear portion 178 and is provided coaxially and integrally with the torsion shaft 36 so as to mesh with the gear portion 178.

  The reduction gear 176 includes a gear portion 182. The gear portion 182 is formed coaxially and integrally with the gear portion 178, and has a sufficiently smaller number of teeth than the gear portion 178. The gear portion 182 is located on the sensor gear 128 side of the cam plate 173.

  On the other hand, as shown in FIG. 2, a ring-shaped rib 184 that is coaxial with the spool 24 is formed on the surface of the cam plate 173 on the sensor gear 128 side. An internal gear 186 having a sufficiently larger number of teeth than the gear portion 182 is formed on the inner peripheral portion of the rib 184, and the gear portion 182 is meshed.

  Therefore, when the spool 24, and thus the torsion shaft 36, rotates about its own axis, this rotational force is decelerated by the gear 180, the gear portion 178, the gear portion 182, and the gear 186 and transmitted to the cam plate 173. The plate 173 rotates around the torsion shaft 36.

  Hereinafter, the rotation direction of the cam plate 173 linked to the rotation of the torsion shaft 36 in the pull-out direction is referred to as “cam pull-out direction”, and the rotation direction of the cam plate 173 linked to the rotation of the torsion shaft 36 in the winding direction. Is referred to as “cam winding direction”.

  Further, as shown in FIG. 1, a lever housing portion 188 is formed in the main body 130 on the opposite side of the pressing portion 168 through the main body 130 of the sensor gear 128. A shaft 190 is formed in the lever accommodating portion 188 so as to protrude in parallel to the spool 24 toward the opposite side of the V gear 126.

  An ALR switching lever 192 is rotatably supported on the shaft 190. A locking projection 198 is formed at the tip of the ALR switching lever 192. One end of the coil spring 200 is locked to the locking protrusion 198. The other end of the coil spring 200 is locked to a holding projection 204 of a spring holding portion 202 formed on the main body 130.

  The ALR switching lever 192 is, for example, a state where the locking projection 198 is positioned between the shaft support portion of the shaft 190 and the holding projection 204 as a neutral position of the ALR switching lever 192, and the shaft 190 with the neutral position as a boundary. When the ALR switching lever 192 rotates in the engagement direction, which is the rotation direction of the sensor gear 128 toward the rotation axis, or in the disengagement direction opposite to the engagement direction, the urging force of the coil spring 200 is rotated. The ALR switching lever 192 is urged to the moving direction side and further rotated.

  Further, as shown in FIG. 1, a connecting claw 206 is formed from the tip of the ALR switching lever 192 toward the V gear 126 side. The connecting claw 206 passes between the spring holding portion 202 and the lever accommodating portion 188 and is located on the side of the outer peripheral portion of the V gear 126, and the ALR switching lever 192 is rotated around the shaft 190 around the rotational axis of the sensor gear 128. When rotating to the side (that is, the torsion shaft 36 side), the connecting claw 206 meshes with the V gear 126.

  On the other hand, a contact portion 210 projects from the tip of the ALR switching lever 192 toward the rotational axis side of the cam plate 173. A cam projection 212 and a cam wall 214 are formed on the surface of the cam plate 173 opposite to the sensor gear 128 corresponding to the contact portion 210.

  The cam protrusion 212 is formed so as to be able to come into contact with the contact portion 210 on the cam winding direction side and from the front end side of the ALR switching lever 192, and until the webbing belt 30 wound up on the spool 24 is completely pulled out. 24. As a result, when the torsion shaft 36 rotates, the cam projection 212 comes into contact with the contact portion 210.

  In contrast, the cam wall 214 is formed so as to be able to come into contact with the contact portion 210 in a state in which the ALR switching lever 192 is rotated in the engagement direction side from the cam withdrawal direction side. In addition, when the spool 24 and eventually the torsion shaft 36 rotate until a certain amount of the webbing belt 30 is left and the webbing belt 30 is wound around the spool 24, the cam wall 214 is brought into contact with the contact portion 210. Touch.

  On the other hand, as shown in FIG. 4, the cam plate 173 is provided with a stopper 220 constituting a restricting means as a restricting portion. The stopper 220 is a plate-like portion protruding from the end face of the cam plate 173 on the sensor gear 128 side, and as shown in FIG. 2, the cam plate corresponding to the fully retracted state in which the webbing belt 30 is fully wound on the spool 24. At the rotation position of 173, the formation position of the stopper 220 on the cam plate 173 is set so that the stopper 220 faces the engagement pin 141 of the connection claw 140 described above.

  In a state where the stopper 220 and the engagement pin 141 face each other, when the connection claw 140 tries to rotate toward the outer peripheral side of the V gear 126, the stopper 220 interferes with the engagement pin 141 and restricts the rotation of the connection claw 140. To do.

<Operation and Effect of First Embodiment>
Next, the operation and effect of the webbing take-up device 10 will be described.

  In the webbing take-up device 10, when the webbing belt 30 wound on the spool 24 is pulled toward the tip end against the urging force of the spiral spring 40, the spool 24 is pulled out in the pulling direction while the webbing belt 30 is pulled out. Rotate.

  The webbing belt 30 pulled out in this way is hung around the occupant's body, and, for example, the tongue plate provided at the intermediate portion in the longitudinal direction of the webbing belt 30 is held by the buckle device provided at the side of the vehicle seat. Thus, the webbing belt 30 is attached to the occupant's body, and the occupant's body is restrained by the webbing belt 30.

  When the vehicle is suddenly decelerated in such a state where the webbing belt 30 is attached, and the hard ball 148 rolls thereby, the sensor claw 150 is pushed up by the hard ball 148. The sensor claw 150 pushed up in this way is engaged with the connection claw 140 of the sensor gear 128 and rotated so as to push up the connection claw 140. As a result, the connecting claw 140 meshes with the V gear 126.

  On the other hand, when the occupant's body moves substantially forward of the vehicle due to inertia when the vehicle decelerates, the webbing belt 30 is rapidly pulled by the occupant's body. In this way, the webbing belt 30 is pulled abruptly, whereby a rotational force in the pull-out direction is suddenly applied to the spool 24.

  Basically, when the spool 24 rotates in the pull-out direction, and the torsion shaft 36 and thus the V gear 126 rotate in the pull-out direction, the W pawl 134 rotates in the pull-out direction together with the V gear 126. However, since the W mass 138 is provided in the W pawl 134, when the spool 24 is suddenly rotated in the pulling-out direction as described above, the W pawl 134 tries to stay at that position without rotating due to inertia.

  As a result, the W pawl 134 rotates relative to the W pawl 134 against the urging force of the sensor spring 136. By the relative rotation of the W pawl 134, the W pawl 134 approaches the inner peripheral portion of the gear ring 154, and the W pawl 134 meshes with the ratchet teeth formed on the inner peripheral portion of the gear ring 154.

  When the W pawl 134 meshes with the gear ring 154, the rotational force of the spool 24 in the pulling direction is transmitted to the gear ring 154 through the torsion shaft 36, the V gear 126, and the W pawl 134, and the gear ring 154 is pulled out together with the V gear 126. Rotate in the direction.

  As the gear ring 154 rotates in the pull-out direction, the friction spring 155 that presses against the outer periphery of the gear ring 154 with a biasing force rotates in the pull-out direction together with the gear ring 154. Thus, when the friction spring 155 rotates by a predetermined angle in the pull-out direction, the pressing portion 158 comes into contact with the engaging pin 141 of the connecting claw 140 and presses the engaging pin 141.

  As described above, the connecting claw 140 rotates when the engaging pin 141 is pressed by the pressing portion 158, and the connecting claw 140 meshes with the V gear 126.

  As described above, when the connecting claw 140 meshes with the V gear 126, the rotational force in the pulling direction of the spool 24 is transmitted to the sensor gear 128 via the torsion shaft 36, the V gear 126, and the connecting claw 140. 128 rotates in the pull-out direction.

  When the sensor gear 128 rotates in the pulling-out direction at a constant angle against the urging force of the return spring 132, the pressing portion 168 provided on the sensor gear 128 presses the pawl portion 166 of the lock pawl 160, and the pawl portion 166 around the shaft 162. Rotate.

  When the pawl portion 166 rotates around the shaft 162 in this manner, the pawl portion 166 meshes with the ratchet portion 172 of the lock base 170, and the rotation of the lock base 170 and thus the spool 24 in the pull-out direction is restricted. As a result, the body of the occupant who is about to move inertially toward the front side of the vehicle can be reliably restrained and held by the webbing belt 30.

  On the other hand, when the child seat is fixed to the vehicle seat equipped with the webbing retractor 10 by the webbing belt 30, the webbing belt 30 is all pulled out.

  When the webbing belt 30 is pulled out in this way and the spool 24 is rotated in the pull-out direction, the torsion shaft 36 rotates in the pull-out direction, and thereby the gear 180 rotates in the pull-out direction. The rotation of the gear 180 in the pull-out direction is transmitted to the cam plate 173 via the gear portions 178 and 182 and the gear 186, and the cam plate 173 rotates in the cam pull-out direction.

  When the cam plate 173 rotates in the cam pull-out direction in this way, the cam protrusion 212 approaches the abutting portion 210 of the ALR switching lever 192 located at the disengagement position from the cam winding direction side. Next, when the spool 24 and eventually the torsion shaft 36 reach the rotational position immediately before the webbing belt 30 wound around the spool 24 is pulled out, the cam protrusion 212 comes into contact with the contact portion 210.

  In this state, when the spool 24 further rotates in the pull-out direction, the cam protrusion 212 presses the abutting portion 210, and the ALR switching lever 192 is moved from the neutral position to the engagement direction side against the urging force of the coil spring 200. Rotate. However, in this state, the ALR switching lever 192 is not rotated to the position where the connecting claw 206 meshes with the V gear 126.

  Thus, the webbing belt 30 is wound around a predetermined portion of the child seat placed on the seat in a state where the webbing belt 30 is fully pulled out. In this state, the tongue plate is engaged with the buckle device to hold the tongue plate, and further, the child seat is held by the webbing belt 30 by winding the slack of the webbing belt 30 onto the spool 24 so that the child seat is placed on the seat. Fixed.

  As described above, when the spool 24 rotates in the winding direction by winding the slack of the webbing belt 30 onto the spool 24, the ALR switching lever 192 further rotates in the engaging direction by the urging force of the coil spring 200. . As a result, the connecting claw 206 meshes with the V gear 126.

  Accordingly, when the spool 24 rotates in the drawing direction in this state, the sensor gear 128 rotates in the drawing direction together with the V gear 126. When the sensor gear 128 rotates in the pull-out direction, the pawl portion 166 of the lock pawl 160 is pressed by the pressing portion 168, and the pawl portion 166 is rotated around the shaft 162. As a result, the pawl portion 166 meshes with the ratchet portion 172 of the lock base 170, and the rotation of the lock base 170 and thus the spool 24 in the pull-out direction is restricted.

  As described above, since the pulling of the webbing belt 30 is restricted by restricting the rotation of the spool 24 in the pull-out direction, the webbing belt 30 that fastens and fixes the child seat does not loosen and is surely placed on the seat. Child seat can be fixed.

  When the tongue plate is removed from the buckle device and the webbing belt 30 is removed from the child seat, the spool 24 is rotated in the winding direction by the urging force of the spiral spring 40, and the webbing belt 30 is wound around the spool 24.

  Thus, when the spool 24 and thus the torsion shaft 36 rotate in the winding direction, the cam plate 173 rotates in the cam winding direction. When the cam plate 173 rotates in the cam winding direction in this way, the cam wall 214 approaches the contact portion 210 in a state where the ALR switching lever 192 is positioned at the engagement position from the cam pull-out direction side.

  When the spool 24 reaches the rotational position immediately before the webbing belt 30 is fully retracted, the cam wall 214 comes into contact with the contact portion 210. Further, when the spool 24 rotates in the winding direction to the rotation position where the webbing belt 30 is fully retracted in this state, the contact portion 210 is pressed against the cam wall 214.

  As a result, the ALR switching lever 192 rotates from the neutral position to the detachment direction side against the biasing force of the coil spring 200, and thereby the ALR switching lever 192 rotates to the detachment position. Thus, when the ALR switching lever 192 rotates to the disengagement position, the connecting claw 206 is separated from the V gear 126, and the engagement between the connecting claw 206 and the V gear 126 is eliminated.

  By the way, for example, an occupant before wearing the webbing belt 30 pulls the webbing belt 30 in order to pull out the webbing belt 30, so that a rapid rotational force in the pull-out direction may be applied to the spool 24.

  Even in such a case, as described above, the W pawl 134 meshes with the ratchet teeth formed on the inner peripheral portion of the gear ring 154, and the rotational force of the spool 24 in the pull-out direction causes the friction spring 155 to move in the pull-out direction together with the gear ring 154. Try to rotate to. Accordingly, even in such a case, the connecting claw 140 is pressed by the pressing portion 158.

  Here, when the webbing belt 30 is fully retracted, as shown in FIG. 2, the stopper 220 faces the engaging pin 141 of the connecting claw 140. Since the stopper 220 is formed on the cam plate 173, the cam plate 173 also rotates when the spool 24 rotates in the pull-out direction.

  However, since the rotation of the spool 24 is sufficiently decelerated and transmitted to the cam plate 173, the rotation amount of the spool 24 is small in the state immediately after the webbing belt 30 is pulled, so that the rotation amount of the cam plate 173 is also sufficient. Small.

  Therefore, in the state immediately after the webbing belt 30 is pulled to pull out the webbing belt 30, the cam plate 173 rotates slightly, but the facing state of the stopper 220 with respect to the engagement pin 141 is not canceled.

  In this state, when the engaging pin 141 is pressed by the pressing portion 158 as described above, the stopper 220 facing the engaging pin 141 is connected even if the connecting claw 140 tries to rotate so as to approach the V gear 126. Interference occurs in the direction of rotation of the claw 140. As a result, the connecting claw 140 cannot mesh with the V gear 126.

  Therefore, in this state, the sensor gear 128 does not rotate in the pull-out direction, and as a result, the pawl portion 166 of the lock pawl 160 does not mesh with the ratchet portion 172 of the lock base 170.

  As a result, the so-called “end lock” in which the rotation of the spool 24 in the pull-out direction is restricted in the fully retracted state of the webbing belt 30 and the state immediately after the start of the pull-out of the webbing belt 30 can be extremely effectively prevented.

  Further, as described above, in the fully retracted state of the webbing belt 30 and the state immediately after the webbing belt 30 starts to be pulled out, the hard ball 148 rolls due to some impact, and the hard ball 148 rotates the connecting claw 140 via the sensor claw 150. Even when trying to move, the stopper 220 restricts the rotation of the coupling claw 140.

  That is, in the present embodiment, as long as at least a part of the stopper 220 faces the connecting claw 140, no end lock occurs even if either the rotation detection mechanism 127 or the acceleration sensor 142 is activated.

  Moreover, both the prevention of the end lock when the rotation detection mechanism 127 is activated and the prevention of the end lock when the acceleration sensor 142 is activated are caused by the stopper 220 restricting the rotation of the connecting claw 140. Done. For this reason, although both the prevention of the end lock when the rotation detection mechanism 127 is activated and the prevention of the end lock when the acceleration sensor 142 is activated are possible, a mechanism for preventing the end lock is extremely provided. It can be simplified effectively. Thereby, the increase in the weight accompanying the increase in the number of parts can be suppressed extremely effectively, and the webbing retractor 10 can be made compact.

  In this way, in the state where the stopper 220 restricts the rotation of the connecting claw 140, the connecting claw 140 is not engaged with the V gear 126, so the sensor gear 334 does not rotate in the pull-out direction. The ratchet teeth of the pawl portion 166 constituting 160 do not mesh with the ratchet portion 172 of the lock base 170. Accordingly, in this state, the lock base 170 rotates in the pull-out direction by the rotation of the spool 24 in the pull-out direction.

  Further, in this state, if the W pawl 134 meshes with the ratchet teeth of the gear ring 154, the gear ring 154 rotates in the pull-out direction by the rotational force of the spool 24 in the pull-out direction. Here, when the gear ring 154 rotates in the pull-out direction, the friction spring 155 whose inner peripheral portion is frictionally engaged with the outer peripheral portion of the gear ring 154 rotates in the pull-out direction together with the gear ring 154 so that the pressing portion 158 is connected to the coupling claw from the initial position. It rotates so that it may approach 140, and the press part 158 engages with the connection nail | claw 140 by this, and tries to push up the connection nail | claw 140. FIG. However, as described above, when the stopper 220 interferes with the connecting claw 140, the pressing portion 158 cannot push up the connecting claw 140, and the pressing portion 158 (friction spring 155) further rotates in the drawing direction. I can't.

  In this way, when the gear ring 154 still rotates in the pull-out direction while the rotation of the friction spring 155 in the pull-out direction is restricted, the friction spring 155 slides with respect to the gear ring 154 (that is, the friction spring 155 and the gear ring 154 A coaxial relative rotation occurs).

  For this reason, even if the rotational force of the spool 24 in the pulling direction is input to each member such as the gear ring 154 and the friction spring 155 in a state where the rotation of the friction spring 155 is restricted, these various members rotate. It will not be damaged by force. For this reason, it is not necessary to set the mechanical strength of these various members to be particularly high, and it is possible to reduce the size and weight of the various members. As a result, the webbing take-up device 10 as a whole can be reduced in size and weight. Also contribute.

  Further, when the webbing belt 30 is pulled out and the spool 24 rotates in the pull-out direction, the cam plate 173 rotates as shown in FIG. By the rotation of the cam plate 173, the facing state between the stopper 220 and the engagement pin 141 is canceled.

  Here, the rotation angle of the cam plate 173 due to the rotation of the spool 24 from the fully retracted state of the webbing belt 30 to the fully pulled-out state of the webbing belt 30 (a state in which the webbing belt 30 is all pulled out from the spool 24) is less than 360 degrees. is there. Therefore, after the opposing state of the stopper 220 and the connecting claw 140 is canceled by the rotation of the spool 24 in the pulling direction, the stopper 220 faces the engaging pin 141 even when the webbing belt 30 is fully pulled out. There is no.

  For this reason, after the webbing belt 30 is pulled out, the pawl portion 166 of the lock pawl 160 is moved to the ratchet portion 172 of the lock base 170 when the vehicle is suddenly decelerated or the webbing belt 30 is pulled out suddenly. They can be engaged with each other, and the rotation of the spool 24 in the pull-out direction can be reliably controlled.

  The mechanism for rotating the stopper 220 in conjunction with the rotation of the spool 24 is basically a mechanism for rotating the ALR switching lever 192 after the webbing belt 30 is fully pulled out. As described above, the mechanism for rotating the ALR switching lever 192 can be applied as a mechanism for rotating the stopper 220, whereby the configuration can be simplified extremely effectively. In this sense, the weight associated with the increase in the number of parts Can be suppressed extremely effectively, and the webbing retractor 10 can be made compact.

  Next, a second embodiment of the present invention will be described. In the description of the present embodiment, the same reference numerals are assigned to the portions that are basically the same as those described in the first embodiment, and a detailed description thereof is omitted.

  FIG. 5 shows the main part of the webbing take-up device 300 according to the second embodiment of the present invention. FIG. 1 explains the main part of the webbing take-up device 300 according to the first embodiment. A corresponding exploded perspective view is shown.

  As shown in this figure, the webbing take-up device 300 includes a cam plate 302 that constitutes a restricting means as a rotating member, instead of the cam plate 173 in the first embodiment. The cam plate 302 basically has the same configuration as the cam plate 173, but unlike the cam plate 173, the cam plate 302 does not include the stopper 220. Instead, the cam plate 302 includes the stopper 304.

  The stopper 304 includes an extending portion 306 that extends from a part of the outer periphery of the cam plate 302 outward in the radial direction of the cam plate 302. A wall portion 308 is formed from the outer peripheral portion of the extending portion 306 toward the V gear 126 side. As described above, the cam plate 302 does not include the stopper 220, but the wall portion 308 of the stopper 304 has the same function as the stopper 220, and the connection is made when the wall portion 308 and the engagement pin 141 are opposed to each other. When the claw 140 tries to turn to the outer peripheral side of the V gear 126, the wall 308 interferes with the engagement pin 141 and restricts the rotation of the connecting claw 140.

  The webbing take-up device 300 does not include the friction spring 155 in the first embodiment, but includes a friction spring 310 instead. The friction spring 310 includes a main body 312. As can be seen by comparing FIG. 5 with FIG. 1, the main body 312 has a substantially C shape with both ends in the circumferential direction spaced apart from the main body 156 of the friction spring 155 in the first embodiment. A pressing portion 314 extends from one end in the circumferential direction of the main body 312 toward the outer side in the radial direction of the main body 312.

  The main body 312 is fitted into the outer peripheral portion of the gear ring 154 in the same manner as the main body 156 of the friction spring 155 in the first embodiment. Here, as shown in FIG. 1, the gear ring 154 in the first embodiment is open on both sides in the axial direction, whereas the webbing take-up device shown in FIG. 5 is used. In 300, a bottom wall 316 is provided at one axial end of the gear ring 154. The bottom wall 316 has a larger diameter than the gear ring 154 and is formed coaxially with the gear ring 154. Further, the bottom wall 316 is formed so that the torsion shaft 36 can pass therethrough, and closes one end of the gear ring 154 in the axial direction.

  A substantially ring-shaped friction ring 318 is mounted on the outer peripheral portion of the gear ring 154. The friction ring 318 has an inner diameter that is larger than the outer diameter of the gear ring 154. The friction ring 318 is formed with one or three (three in this embodiment) engaging claws 320 at predetermined intervals along the circumferential direction. Corresponding to the engaging claw 320, an annular engaging groove 322 is formed in the bottom wall 316 along the outer peripheral portion of the bottom wall 316 at least in a predetermined range. The engagement claw 320 is fitted in the engagement groove 322, and the engagement claw 320, and thus the friction ring 318, with respect to the gear ring 154 within the formation range of the engagement groove 322 along the outer peripheral portion of the bottom wall 316. Coaxially relative rotation is possible.

  Further, in a state where the friction ring 318 is mounted on the outer peripheral portion of the gear ring 154, a space having a space equal to or larger than the thickness of the friction spring 310 is formed between the outer peripheral portion of the gear ring 154 and the inner peripheral portion of the friction ring 318. The main body 312 of the friction spring 310 is accommodated in this space.

  In addition, a pressing portion 324 extends from a part of the outer periphery of the friction ring 318 outward in the radial direction. The pressing part 324 is bent toward the V gear 126 at the middle part in the longitudinal direction. The tip side of the pressing portion 324 is opposed to the connecting claw 140 along the rotational circumferential direction of the gear ring 154 with respect to the bent portion at the middle portion in the longitudinal direction of the pressing portion 324, and the friction ring 318 rotates in the pulling direction. When the pressing portion 324 engages with the connecting claw 140, the pressing portion 324 pushes up the connecting claw 140 and meshes the connecting claw 140 with the V gear 126. In other words, in the present embodiment, the pressing portion 324 of the friction ring 318 is responsible for the function that the pressing portion 158 of the friction spring 155 pushes up the connecting claw 140 in the first embodiment.

  Further, the main body portion of the friction ring 318 is interrupted at a part in the circumferential direction, and an accommodating portion 326 is provided at the interrupted portion. The accommodating portion 326 includes a pair of side walls 328 and 330 facing each other along the circumferential direction of the friction ring 318, and a pressing portion 314 of the friction spring 310 is inserted between the side walls 328 and 330. A part of these side walls 328 and 330 extends to the opposite side of the V gear 126 from the main body portion of the friction ring 318. A peripheral wall 332 is provided between the side walls 328 and 330 on the opposite side of the main body portion of the friction ring 318 from the V gear 126. The peripheral wall 332 is formed so as to connect the end portions of both side walls 328 and 330 on the radially inner side of the friction ring 318, and thus the accommodating portion 326 opens toward the radially outer side of the friction ring 318. It is formed in a concave shape.

  On the other hand, the webbing retractor 300 does not include the sensor gear 128 in the first embodiment, but includes a sensor gear 334 instead. The sensor gear 334 has basically the same configuration as the sensor gear 128 in the first embodiment, but the sensor gear 334 is different from the sensor gear 128 in that a window 336 is formed in the main body 130. The window portion 336 is a part of the main body 130 and penetrates the main body 130 in the axial direction and the radial direction of the spool 24.

  A spring seat 338 is provided inside the window 336. The spring seat 338 is provided integrally with the sensor gear 334 in a state in which the spring seat 338 is displaced to the V gear 126 side from the end surface of the main body 130 on the cam plate 302 side. A cylindrical boss 342 protrudes from the spring seat 338 toward the cam plate 302, and a coil portion of a torsion coil spring 340 as a return means is fitted into the boss 342. One end of the torsion coil spring 340 is locked to a locking portion 344 provided on the spring seat 338.

  In contrast, the other end of the torsion coil spring 340 extends to the side of the spring seat 338. The other end of the torsion coil spring 340 is located between the side wall 328 and the side wall 330 on the cam plate 302 side with respect to the main body portion of the friction ring 318.

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

  In the webbing take-up device 300, the wall portion 308 of the stopper 304, which replaces the stopper 220 in the first embodiment, is on the rotation direction side for the connection claw 140 to mesh with the V gear 126 with respect to the connection claw 140. When the interference occurs, the connecting claw 140 cannot mesh with the V gear 126. In this state, since the connecting claw 140 is not engaged with the V gear 126, the sensor gear 334 does not rotate in the pull-out direction. 172 is not engaged. Accordingly, in this state, the lock base 170 rotates in the pull-out direction by the rotation of the spool 24 in the pull-out direction.

  Further, in this state, if the W pawl 134 meshes with the ratchet teeth of the gear ring 154, the gear ring 154 rotates in the pull-out direction by the rotational force of the spool 24 in the pull-out direction. Here, when the gear ring 154 rotates in the pull-out direction, the friction spring 310 whose inner peripheral portion frictionally engages with the outer peripheral portion of the gear ring 154 rotates in the pull-out direction together with the gear ring 154 so that the pressing portion 314 is a side wall of the housing portion 326. The friction ring 318 is pressed by pressing 328 in the pull-out direction. Since the friction ring 318 is opposite to the side wall 330 of the accommodating portion 326 and the other end of the torsion coil spring 340 is opposed to the side wall 330 when the friction ring 318 attempts to rotate in the pull-out direction by the pressing force from the pressing portion 314. The abutting torsion coil spring 340 biases the friction ring 318 so as to resist rotation of the friction ring 318 in the pull-out direction.

  As the friction ring 318 rotates in the pull-out direction against the biasing force of the torsion coil spring 340, the pressing portion 324 in the initial state (that is, in the initial position) shown in FIG. , So as to engage with the connecting claw 140 and push up the connecting claw 140. However, as described above, when the wall portion 308 of the stopper 304 interferes with the connecting claw 140, the pressing portion 324 cannot push up the connecting claw 140, and the pressing portion 324 (friction ring 318) further extends in the pull-out direction. Can not be rotated.

  Thus, when the gear ring 154 still rotates in the pull-out direction with the rotation of the friction ring 318 restricted in the pull-out direction, the friction spring 310 slides with respect to the gear ring 154 (that is, the friction spring 310 and the gear ring 154 A coaxial relative rotation occurs).

  For this reason, even if the rotational force of the spool 24 in the pulling direction is input to each member such as the gear ring 154 and the friction spring 310 in a state where the rotation of the friction ring 318 is restricted, these various members rotate. It will not be damaged by force. Therefore, the mechanical strength of these various members does not need to be set particularly high, and the various members can be reduced in size and weight. As a result, the webbing retractor 300 as a whole can be reduced in size and weight. Also contribute.

  On the other hand, after the pressing portion 324 is interfered with the connecting claw 140 as described above, or after the pressing portion 324 pushes up the connecting claw 140 and the connecting claw 140 meshes with the V gear 126 as shown in FIG. When the pulling force applied to the webbing belt 30 is eliminated, and thus the rotation of the spool 24 in the pull-out direction is eliminated, the rotation of the gear ring 154 in the pull-out direction is also eliminated. The pressing force in the pulling direction that 314 applies to the side wall 328 of the friction ring 318 is also eliminated.

  As described above, the friction ring 318 is biased in the winding direction opposite to the pulling direction by the biasing force of the torsion coil spring 340. For this reason, the friction ring 318 is attached to the torsion coil spring 340 by eliminating the pressing force in the pulling direction applied to the side wall 328 of the friction ring 318 against the urging force of the torsion coil spring 340. The force is rotated in the winding direction, and the pressing portion 324 returns to the initial position as shown in FIG.

  As a result, the state where the pressing portion 324 is engaged with the connecting claw 140 is not unnecessarily maintained, and if the tensile force applied to the webbing belt 30 is eliminated as described above, the pressing portion 324 is connected to the connecting claw. 140 can be spaced apart. In this state, if the hard ball 148 of the acceleration sensor 142 does not push up the sensor claw 150, the connection claw 140 can be rotated away from the V gear 126 by its own weight, and the rotation restriction of the V gear 126 can be eliminated.

In the webbing take-up device 300, as described above, the pressing portion 314 of the friction spring 310 and the other end of the torsion coil spring 340 are positioned between the side wall 328 and the side wall 330 of the housing portion 326. It has become. As described above, the friction spring 310 pressing portion 314 that applies a rotational force in the pull-out direction to the friction ring 318 and the other end of the torsion coil spring 340 that biases the friction ring 318 in the winding direction are arranged close to each other. Thus, it is possible to reduce the arrangement space of the portion that applies the rotational force in the drawing direction and the winding direction to the friction ring 318.

  In the present embodiment, the torsion coil spring 340 is applied to the return means. However, the return means may be configured to urge the friction ring 318 in the winding direction with respect to the sensor gear 334. The shape of the biasing means constituting the return means is not particularly limited. Therefore, for example, inside the window portion 336, the direction from one end to the other end is along the winding direction, one end is in contact with the sensor gear 334, the other end is in contact with the wall portion 308, and the friction ring 318 is A compression coil spring urging in the winding direction may be used as the return means.

It is a disassembled perspective view which shows the structure of the principal part of the webbing take-up device according to the first embodiment of the present invention. It is a front view which shows the state which the control means has controlled the displacement of the connection member. It is a front view corresponding to FIG. 2 which shows the state by which the displacement control of the connection member by the control means was cancelled | released. It is a disassembled perspective view which shows the outline of the whole structure of the webbing winding apparatus concerning the 1st Embodiment of this invention. It is a disassembled perspective view which shows the structure of the principal part of the webbing retractor which concerns on the 2nd Embodiment of this invention. It is a schematic front view which shows the state which has an engaging member in an initial position. It is a schematic front view corresponding to FIG. 6 which shows the state which the engaging member rotated to the connection member side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Webbing winding device 24 Spool 30 Webbing belt 127 Rotation detection mechanism (rotation detection means)
128 Sensor gear (Rotating body)
140 Connection claw (connection member)
142 Acceleration sensor (acceleration detection means)
154 Gearing (interlocking member in the first embodiment, second rotating member in the second embodiment)
155 Friction spring (engagement member)
160 Lock pawl (lock member)
173 cam plate (first rotating member, regulating means)
220 Stopper (Regulator, Regulator)
300 Webbing take-up device 302 Cam plate (first rotating member)
310 Friction spring (third rotating member)
318 Friction ring (engagement member)
340 Torsion coil spring (return means)

Claims (5)

The base end portion of the long belt-like webbing belt is locked, and the webbing belt is wound up and stored by rotating in one winding direction around the axis, and the webbing belt is pulled to the distal end side to pull the webbing belt. A spool in which the webbing belt is pulled out by being rotated in a drawing direction opposite to the winding direction;
A rotating body coaxially rotatable with respect to the spool;
Provided on the rotating body so as to be displaceable between a position capable of being directly or indirectly engaged with the spool and a position where the engagement is released, and is directly or indirectly engaged with the spool. A connecting member that rotates the rotating body in the pull-out direction together with the spool that rotates in the pull-out direction,
A locking member that directly or indirectly engages the spool in conjunction with the rotating body that rotates in the pull-out direction and restricts rotation of the spool in the pull-out direction;
Acceleration detecting means that operates in a sudden deceleration state of the vehicle and moves the connecting member to the engageable position;
A rotation detecting means that operates by abrupt rotation of the spool in the pull-out direction and moves the connecting member to the engageable position;
In a state where the webbing belt is wound and housed on the spool, it engages with the connecting member, and it can reach the position where it can be engaged regardless of which of the acceleration detecting means and the rotation detecting means is operated . Restriction means for restricting displacement of the connecting member;
And the connecting member moved to the engageable position by the actuated acceleration detecting means and the connecting member moved to the engageable position by the actuated rotation detecting means are the same. A webbing take-up device as a member . The rotation of the spool is transmitted at a reduced speed, and from the pulled-out state in which the entire amount of the webbing belt is pulled out from the spool to the fully retracted state in which the webbing belt is wound around and stored in the spool. A first rotating member that rotates coaxially with the spool by a predetermined angle of less than one rotation;
The connection to the engageable position is provided integrally with the first rotation member, facing the connection member on the displacement direction side of the connection member to the engageable position in the fully retracted state. A restricting portion for restricting the displacement of the member;
Comprising the regulating means including
The webbing take-up device according to claim 1. An interlocking member that moves in a predetermined direction in conjunction with rotation of the spool in the pull-out direction at a speed equal to or greater than a predetermined size;
It moves with the interlocking member and moves from an initial position to a position engageable with the connecting member, engages the connecting member with the spool, and reaches a position engageable with the connecting member. An engagement member capable of eliminating the movement associated with the interlocking member,
The webbing take-up device according to claim 1 or 2, wherein the rotation detecting means is configured to include. An engaging member that moves from an initial position to an engaging position with the connecting member when the spool rotates in the pulling direction at a speed equal to or greater than a predetermined size, and engages the connecting member with the spool;
The engagement member is urged toward the initial position, and the engagement member is moved to the initial position when transmission of the rotational force of the spool in the pull-out direction to the engagement member is canceled. Return means;
The webbing take-up device according to claim 1 or 2, wherein the rotation detecting means is configured to include. A second rotating member that rotates by being directly or indirectly connected to the spool when the spool rotates in the pull-out direction at a speed equal to or greater than a predetermined size;
An engaging member that rotates from an initial position and reaches the position where the connecting member can be engaged with the spool, thereby engaging the connecting member with the spool;
It is coaxially attached to the second rotating member so as to be engageable with the engaging member, and the engaging member can be engaged with the connecting member by rotating in the pull-out direction together with the second rotating member. A third rotating member capable of rotating relative to the second rotating member in a state in which the rotation is restricted,
The engagement member rotated in the pull-out direction from the initial position is biased toward the initial position, and transmission of rotational force in the pull-out direction from the third rotation member to the engagement member is eliminated. Returning means for rotating the engagement member to the initial position in a state;
The webbing take-up device according to claim 1 or 2, wherein the rotation detecting means is configured to include.

Images