JP2018162043A - Seat belt retractor and seat belt device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a moving distance of an occupant.SOLUTION: A seat belt retractor includes: a spool which takes up a seat belt; a base frame which rotatably houses the spool; a pretensioner having a rotating body which rotates the spool in a seat belt taking-up direction during operation; a lock mechanism having a lock member which rotates with rotation of the spool during normal time and hinders rotation of the spool in a seat belt drawing direction during the operation; a torsion bar which is twisted by the spool rotating relative to the lock member in the drawing direction; and a stopper mechanism which stops twisting of the torsion bar when triggered by actuation of the pretensioner. The stopper mechanism is disposed at a side opposite to the side where the lock member is disposed with respect to the torsion bar.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a seat belt retractor and a seat belt device.

  2. Description of the Related Art Conventionally, a seat belt retractor that includes a spool that winds up a seat belt, a base frame that rotatably accommodates the spool, and a pretensioner that winds up the seat belt and removes slack in the seat belt in an emergency is known. (For example, see Patent Document 1). In such a seat belt retractor, there are a lock mechanism that locks the rotation of the spool in the direction in which the seat belt is pulled out in an emergency, and a torsion bar that absorbs energy acting on the occupant from the seat belt when the lock mechanism is activated by torsional deformation. May be provided.

International Publication No. 2010/060558

  The seat belt retractor provided with the lock mechanism and the torsion bar as described above absorbs the energy acting on the occupant from the seat belt in the operation state of the lock mechanism by allowing the seat belt to be pulled out in an emergency. However, since the withdrawal of the seat belt is permitted, the movement amount of the occupant may increase too much.

  Therefore, in the present disclosure, a seat belt retractor that can suppress the movement amount of the occupant is provided.

In one aspect of the present disclosure,
A spool that winds up the seat belt;
A base frame that rotatably accommodates the spool;
A pretensioner having a rotating body that rotates the spool in the winding direction of the seat belt during operation;
A lock mechanism having a lock member that rotates together with the rotation of the spool during normal operation and prevents rotation of the spool in the pull-out direction of the seat belt during operation;
A torsion bar that twists when the spool rotates relative to the lock member in the pull-out direction;
A stopper mechanism for stopping torsion of the torsion bar triggered by the operation of the pretensioner,
The stopper mechanism is provided with a seat belt retractor in which the lock member is disposed on a side opposite to a side where the lock member is disposed with respect to the torsion bar.

  According to one aspect of the present disclosure, the amount of movement of the occupant can be suppressed by the stopper mechanism that stops the torsion bar torsion using the operation of the pretensioner as a trigger.

It is a figure which shows an example of a structure of a seatbelt apparatus. It is a side view which shows an example of a seatbelt retractor. It is a figure which shows the cut surface of a seatbelt retractor by arrow AA (refer FIG. 2). It is a disassembled perspective view of the stopper mechanism of a seatbelt retractor. It is a whole exploded perspective view of a seatbelt retractor. It is a figure which shows the state before the rod inject | emitted from the pretensioner contacts a slider. It is a figure which shows the state which the rod inject | emitted from the pretensioner contacted the slider. It is a figure which shows the state which the rod inject | emitted from the pretensioner pushed out the slider. It is a perspective view which shows the state which a joint lever rotates. It is a figure which shows the state before a lock lever engages with a lock cam gear. It is a figure which shows the state after a lock lever engages with a lock cam gear. It is a perspective view which shows an example of a lock cam gear. It is a perspective view which abbreviate | omits and shows an example of a stopper mechanism. It is sectional drawing which shows an example of a stopper mechanism. It is a figure which shows the state before operation | movement of an arm. It is a figure which shows the state in operation | movement of an arm. It is a figure which shows the state after operation | movement of an arm. It is a figure which shows the state before the operation | movement of a pawl. It is a figure which shows the state in operation | movement of a pawl. It is a figure which shows the state after the operation | movement of a pawl.

  Hereinafter, an embodiment according to the present disclosure will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating an example of a configuration of a seat belt device. A seat belt device 101 shown in FIG. 1 is an example of a seat belt device mounted on a vehicle. The seat belt device 101 includes, for example, a seat belt 104, a retractor 103, a shoulder anchor 106, a tongue 107, and a buckle 108.

  The seat belt 104 is an example of a seat belt that restrains an occupant 111 sitting on the seat 102 of the vehicle, and is a belt-like member that is wound around the retractor 103 so as to be drawn out. The seat belt is also referred to as webbing. The belt anchor 105 at the tip of the seat belt 104 is fixed to the floor of the vehicle body or the seat 102.

  The retractor 103 is an example of a seat belt retractor that enables the seat belt 104 to be retracted or pulled out. The retractor 103 restricts the seat belt 104 from being pulled out of the retractor 103 when an acceleration / deceleration or a vehicle angle greater than or equal to a predetermined value is detected during a vehicle collision or the like. The retractor 103 is fixed to the seat 102 or a vehicle body near the seat 102. The retractor 103 is an example of a seat belt retractor.

  The shoulder anchor 106 is an example of a belt insertion tool through which the seat belt 104 is inserted, and is a member that guides the seat belt 104 pulled out from the retractor 103 toward the shoulder portion of the occupant 111.

  The tongue 107 is an example of a belt insertion tool through which the seat belt 104 is inserted, and is a component that is slidably attached to the seat belt 104 guided by the shoulder anchor 106.

  The buckle 108 is a part to which the tongue 107 is detachably connected, and is fixed to the floor of the vehicle body or the seat 102, for example.

  In a state where the tongue 107 is connected to the buckle 108, the portion of the seat belt 104 between the shoulder anchor 106 and the tongue 107 is a shoulder belt portion 109 that restrains the chest and shoulders of the occupant 111. In a state where the tongue 107 is connected to the buckle 108, the portion of the seat belt 104 between the belt anchor 105 and the tongue 107 is a lap belt portion 110 that restrains the waist of the occupant 111.

  FIG. 2 is a side view showing an example of a seat belt retractor. FIG. 3 is a view showing a cut surface of the seat belt retractor as viewed in the direction of arrows AA (see FIG. 2). FIG. 4 is an exploded perspective view of the stopper mechanism of the seat belt retractor. FIG. 5 is an overall exploded perspective view of the seat belt retractor. In FIG. 5, there are cases where the arrangement of the components in the axial direction of the spool 2 is moved back and forth due to space limitations.

  The retractor 1 illustrated in FIGS. 2 to 5 is an example of a seat belt retractor, and more specifically, is an example of the retractor 103 illustrated in FIG. 1. Hereinafter, the configuration of the retractor 1 will be described with reference to FIGS.

  The retractor 1 includes a spool 2, a base frame 3, a spring unit 4, a pretensioner 5, a lock mechanism 6, a torsion bar 21, a stopper mechanism 8, and a joint lever 92.

  The spool 2 is a rotating member that winds up a seat belt that restrains an occupant. One end of the spool 2 is connected to the spring unit 4. The spool 2 is biased by the spiral spring 43 stored in the spring unit 4 so as to rotate in the direction of winding the seat belt. The rotating shaft of the spool 2 includes a shaft 2a and a bush 42 fixed to one end of the shaft 2a. Spool bearings 24 and 25 are attached to both ends of the spool 2.

  The spring unit 4 is an example of a spring mechanism that biases the spool 2 so that the spool 2 rotates in the seat belt winding direction. The spring unit 4 includes a spiral spring 43 and a spring cover 41.

  The spiral spring 43 has one end connected to the rotation shaft of the spool 2 and the other end connected to the outer peripheral wall of the spring cover 41, and the spool 2 rotates so that the spool 2 rotates in the seat belt winding direction. It is an example of the elastic body which urges | biases. One end of the spiral spring 43 is connected to a bush 42 that is rotatably attached to the spool 2. The spiral spring 43 constantly urges the spool 2 in the seat belt winding direction. One end of the spiral spring 43 is hooked in a groove formed in the bush 42, for example.

  The spring cover 41 has an outer peripheral wall to which the other end of the spiral spring 43 is connected, and accommodates the spiral spring 43 inside the outer peripheral wall. The spring cover 41 is fixed to the retainer 81.

  The means for applying the force for rotating the spool 2 in the seat belt winding direction is not limited to the spring unit 4 and may be another mechanism using an electric motor or the like.

  A torsion bar 21 that forms an axial center extends in a cavity formed in the center of the spool 2. One end of the torsion bar 21 is connected to the inner surface of the end of the spool 2 on the side where the spring unit 4 and the stopper mechanism 8 are connected. The other end of the torsion bar 21 is connected to the locking base 22.

  The locking base 22 has one end that fits into the hollow portion of the spool 2 and the other end that is rotatably supported by the retainer cover 35 via a bearing cap 36. One end of the locking base 22 is formed with a shaft portion 22 a that passes through the center holes of the paddle wheel 51 and the spool bearing 24. The shaft portion 22 a is fitted into the central hole of the paddle wheel 51. A pawl 61 of the locking mechanism 6 is disposed on the other end side of the locking base 22 so as to be rotatable within the cover plate 66.

  During normal times when the pretensioner 5 and the lock mechanism 6 are not operating, the torsion bar 21 is configured to rotate integrally with the spool 2. When the pretensioner 5 is operated, the pretensioner 5 rotates the spool 2 with the paddle wheel 51, whereby the seat belt can be wound around the spool 2. When the lock mechanism 6 is operated, the pawl 61 is engaged with the internal teeth 32 a formed on the side surface 32 of the base frame 3, whereby the rotation of the spool 2 is locked. This prevents the seat belt from being pulled out.

  When the seat belt withdrawing direction is further blocked by the lock mechanism 6 and the seat belt withdrawing force is further applied, the torsional deformation of the torsion bar 21 can limit the seat belt load. Absorb energy.

  When the spool 2 is rotated in the pull-out direction by the seat belt pulled out when the lock mechanism 6 is operated, the occupant's energy is absorbed by the plastic deformation of the metal deformation pin 23 inserted into the spool 2. Note that the deformation pin 23 may be omitted when the torsion bar 21 has a sufficient energy absorption capability.

  The base frame 3 is a housing that rotatably accommodates the spool 2 and forms a skeleton of the retractor 1. The base frame 3 includes, for example, a pair of side surfaces 31 and 32 that face each other, a back surface 33 that connects the side surfaces 31 and 32, and a tie plate 34 that faces the back surface 33 and is connected to the side surfaces 31 and 32. ing. The spring unit 4 and the stopper mechanism 8 are disposed outside the side surface 31. A paddle wheel 51 of the pretensioner 5 is disposed inside the side surface 32. A lock mechanism 6 is disposed outside the side surface 32. The lock mechanism 6 is accommodated in a retainer cover 35 connected to the base frame 3.

  In the retainer cover 35, a vehicle sensor 7 for detecting a rapid change in the acceleration / deceleration and inclination of the vehicle is disposed. The vehicle sensor 7 has one built-in sphere and an actuator 71 that is swung by the movement of the sphere. The vehicle sensor 7 is housed in a recess formed in the retainer cover 35. The vehicle sensor 7 is configured such that, when acceleration / deceleration or a sudden change in inclination occurs in the vehicle body, the tip of the actuator 71 swings as the sphere moves. By this swinging, the actuator 71 is engaged with the external teeth 62 a of the lock gear 62. Further, when the vehicle sensor 7 detects a sudden change in acceleration / deceleration or inclination of the vehicle, the vehicle sensor 7 transmits a detection signal indicating that the sudden change has been detected to other electronic components and electronic control systems mounted on the vehicle. It may be configured to.

  The pretensioner 5 is a mechanism that winds up the seat belt and removes the slack of the seat belt in an emergency in which an acceleration / deceleration greater than or equal to a predetermined value or a vehicle angle is detected such as when a vehicle collides. The pretensioner 5 includes a paddle wheel 51 connected to the end of the spool 2 via a torsion bar 21 and a locking base 22, a power generation unit 52 that rotates the paddle wheel 51, and a pretensioner cover that houses the paddle wheel 51. 53.

  The paddle wheel 51 is an example of a rotating body that rotates the spool 2 in the seat belt winding direction when the pretensioner 5 is operated. The paddle wheel 51 is connected coaxially with the spool 2. On the outer periphery of the paddle wheel 51, a plurality of engaging teeth 51a that protrude outward in the radial direction of the paddle wheel 51 are formed.

  The power generation unit 52 includes, for example, a rod 52a, a guide pipe 52b, a gas generation device 52c, a stopper spring 52d, and a piston 52e.

  The rod 52a is a deformable injection body that engages with the engagement teeth 51a and rotates the paddle wheel 51. The rod 52a is a rod-shaped member made of synthetic resin, for example. When pressure is applied to the rear end portion of the rod 52a, the rod 52a moves while plastically deforming along the shape of the guide pipe 52b in the guide pipe 52b. The total length of the rod 52a is set to such a length that the rear end of the rod 52a is not released from the guide pipe 52b when the pretensioner 5 is in an operation-completed state. With such a configuration, it is possible to suppress the release of gas from the guide pipe 52b after the operation of the pretensioner 5 is completed.

  The projectile that rotates the paddle wheel 51 by engaging with the engaging teeth 51a is not limited to the rod-shaped rod 52a. For example, such an injection body has a member using a plurality of metal or resin spheres, a member using a plurality of twin balls in which two metal or resin spheres are connected, or teeth are formed in advance. A flat rack may be used.

  The guide pipe 52b accommodates the rod 52a and guides the movement of the rod 52a. The guide pipe 52b has a front end portion that faces the engagement teeth 51a of the paddle wheel 51, and a rear end portion that is extended by a length necessary for the movement of the rod 52a and arranged along the outer shape of the retractor 1. A pipe opening 52g is formed at the tip of the guide pipe 52b. The rod 52a is ejected from the pipe opening 52g toward the engagement tooth 51a of the paddle wheel 51.

  The gas generator 52c is disposed at the rear end of the guide pipe 52b, and generates a gas that gives power to the rod 52a. The gas generator 52c is, for example, a micro gas generator that ejects gas to the guide pipe 52b in response to a detection signal from at least one of the vehicle sensor 7 and an acceleration sensor mounted on the vehicle body. Between the gas generator 52c and the rod 52a, a piston 52e having a pressure receiving surface that seals the gap between the rod 52a and the inner peripheral surface of the guide pipe 52b and receives the gas pressure from the gas generator 52c is disposed. ing.

  According to such a power generation unit 52, in a normal state, the state in which the rod 52a is accommodated in the guide pipe 52b is maintained by the rigidity of the rod 52a. When gas is generated from the gas generator 52c, the rod 52a moves in the guide pipe 52b while being plastically deformed, and is discharged into the pretensioner cover 53 from the pipe opening 52g. At this time, the rod 52a engages with the engagement teeth 51a of the paddle wheel 51 while being plastically deformed, and rotates the paddle wheel 51. The rod 52a moves along the shape in the pretensioner cover 53, and finally stops in contact with the guide pipe 52b, the rod 52a itself, the pretensioner cover 53, the stopper pin 39, or other parts. The rod 52 a is guided along the shape in the pretensioner cover 53. The stopper pin 39 is fixed to the pretensioner cover 53 by a push nut 37.

  The pretensioner cover 53 is an example of a cover member that houses at least the paddle wheel 51. The pretensioner cover 53 is a metal part having a substantially bowl shape or a box shape, and is fixed to the inside of the side surface 32 and the back surface 33 of the base frame 3. The pretensioner cover 53 has an opening 53a into which the end of the spool 2 is inserted. The opening 53 a receives the radial load of the spool 2 indirectly via the spool bearing 24.

  In the form in which the spool bearing 24 is omitted, the inner edge of the opening 53a of the pretensioner cover 53 may directly receive the radial load of the spool 2.

  The lock mechanism 6 locks the withdrawal of the seat belt in an emergency in which an acceleration / deceleration greater than a predetermined value or a vehicle angle is detected such as when a vehicle collides. The lock mechanism 6 includes a pawl 61, a locking base 22, a lock gear 62, and a flywheel 63.

  The pawl 61 is an example of a locking claw that is swingably disposed on the end surface of the locking base 22. An opening through which the locking base 22 can be inserted is formed on the side surface 32 of the base frame 3. A plurality of internal teeth 32a are formed on the inner edge of the opening. The pawl 61 is disposed so as to be engageable with a plurality of internal teeth 32a formed on the inner edge of the opening.

  The locking base 22 is an example of a locking member that rotates together with the rotation of the spool 2 at a normal time when the locking mechanism 6 is not operated and prevents the spool 2 from rotating in the seat belt pull-out direction when the locking mechanism 6 is operated. The locking base 22 has a shaft portion 22 b supported by the retainer cover 35, and the shaft portion 22 b is fitted in the shaft hole 62 c of the lock gear 62. A plurality of external teeth 62 a are formed on the outer periphery of the lock gear 62. An actuator 71 of the vehicle sensor 7 is engaged with the external teeth 62a. A flywheel 63 is swingably attached to the lock gear 62. The retainer cover 35 has a circular recess. A plurality of internal teeth 35 a are formed inside the concave portion of the retainer cover 35. The tip of the flywheel 63 is engaged with the internal teeth 35a. The hook spring 64 biases the tip of the flywheel 63 in a direction away from the internal teeth 35a.

  The flat portion of the lock gear 62 is formed with a cam hole 62b that curves from the outer edge side toward the inner edge side. A boss 61a protruding from the flat surface of the pawl 61 is inserted into the cam hole 62b. As the boss 61a moves along the cam hole 62b, the pawl 61 swings. The pawl spring 65 urges the tip of the pawl 61 in a direction away from the internal teeth 32 a formed on the side surface 32 of the base frame 3. The pawl spring 65 is accommodated in an opening 62 d formed in the flat portion of the lock gear 62. One end of the pawl spring 65 is attached to a locking portion near the opening 62d, and the other end of the pawl spring 65 is attached to a boss 61a of the pawl 61.

  The flywheel 63 is a member that is swingably disposed between the retainer cover 35 and the lock gear 62. When the seat belt pull-out acceleration is equal to or less than a predetermined threshold, the force by which the hook spring 64 biases the flywheel 63 is set to be larger than the inertial force generated in the flywheel 63. When the pull-out acceleration of the seat belt is equal to or less than a predetermined threshold, the flywheel 63 rotates together with the lock gear 62.

  On the other hand, when the seat belt pull-out acceleration exceeds a predetermined threshold, the inertial force generated in the flywheel 63 is greater than the force with which the hook spring 64 biases the flywheel 63. For this reason, the front-end | tip part of the flywheel 63 approaches and engages with the internal tooth 35a of the retainer cover 35. FIG.

  Next, the operation of the lock mechanism 6 will be described.

  Since the actuator 71, the flywheel 63, and the pawl 61 are in a non-engagement state at normal times, the locking base 22 and the lock gear 62 rotate as the spool 2 rotates.

  Next, an emergency operation will be described.

  First, the operation of the lock mechanism 6 by sudden pulling out of the seat belt will be described.

  When the seat belt pull-out acceleration exceeds a predetermined threshold due to the seat belt being pulled out of the spool 2, the spool 2 rotates in the seat belt pull-out direction, and the locking base 22 rotates in the same direction together with the spool 2. To do. At this time, the flywheel 63 is delayed due to inertia with respect to the sudden withdrawal of the seat belt, and swings from the center of rotation to the outer peripheral side. When the flywheel 63 swings to the outer peripheral side, the tip end portion of the flywheel 63 meshes with the inner teeth 35a of the retainer cover 35, so that the lock gear 62 is prevented from rotating.

  On the other hand, since the locking base 22 continues to rotate, relative rotation (rotation phase difference) between the locking base 22 that continues to rotate in the direction in which the seat belt is pulled out and the lock gear 62 that is prevented from rotating. Will occur. Along with the occurrence of the rotational phase difference, the pawl 61 that is swingably attached to the locking base 22 also rotates together with the locking base 22.

  However, the rotation of the lock gear 62 in which the boss 61 a of the pawl 61 is inserted into the cam hole 62 b is blocked by the flywheel 63. Therefore, the boss 61a moves along the cam hole 62b in the moving direction according to the pulling-out direction of the seat belt against the urging force of the pawl spring 65. As a result, the pawl 61 swings along the end surface of the locking base 22, and the tip end portion of the pawl 61 meshes with the internal teeth 32 a formed on the side surface 32 of the base frame 3. As a result, since the rotation of the locking base 22 in the pulling direction is prevented, the rotation of the spool 2 in the pulling direction is also prevented.

  Next, the operation of the lock mechanism 6 by the vehicle sensor 7 will be described.

  When the vehicle sensor 7 detects an acceleration / deceleration greater than or equal to a predetermined value such as when the vehicle collides or the vehicle angle, the actuator 71 meshes with the external teeth 62a of the lock gear 62, so that the lock gear 62 is prevented from rotating.

  On the other hand, the seat belt is pulled by the movement of the occupant and pulled out from the spool 2. Accordingly, the spool 2 rotates in the seat belt pull-out direction, and the locking base 22 that rotates together with the spool 2 also rotates in the same direction. Therefore, a relative rotation (rotation phase difference) occurs between the locking base 22 that rotates in the seat belt pull-out direction and the lock gear 62 that is prevented from rotating. Along with the occurrence of the rotational phase difference, the pawl 61 that is swingably attached to the locking base 22 also rotates together with the locking base 22.

  However, the rotation of the lock gear 62 in which the boss 61 a of the pawl 61 is inserted into the cam hole 62 b is blocked by the actuator 71. Therefore, the boss 61a moves along the cam hole 62b in the moving direction according to the pulling-out direction of the seat belt against the urging force of the pawl spring 65. As a result, the pawl 61 swings along the end surface of the locking base 22, and the pawl tip of the pawl 61 meshes with the internal teeth 32 a formed on the side surface 32 of the base frame 3. As a result, since the rotation of the locking base 22 in the pulling direction is prevented, the rotation of the spool 2 in the pulling direction is also prevented.

  Next, an emergency operation by the pretensioner 5 will be described.

  When the pretensioner 5 is activated in the event of an emergency in which an acceleration / deceleration greater than a predetermined value or a vehicle angle is detected such as when a vehicle collides, gas is generated from the gas generator 52c. The rod 52a pushed by the generated gas moves along the guide pipe 52b. The rod 52a released from the pipe opening 52g rotates the paddle wheel 51 in the seat belt winding direction, so that the spool 2 also rotates in the seat belt winding direction. As a result, the seat belt is wound around the spool 2.

  When the winding of the seat belt is completed, the seat belt is pulled due to the inertia of the occupant, so that the spool 2 starts to rotate in the reverse direction of the seat belt. When the winding of the seat belt by the operation of the pretensioner 5 is completed, the gas pressure is maintained by the piston 52e remaining inside the guide pipe 52b. Since the gas pressure becomes resistance by holding the gas pressure, rotation of the locking base 22 at the end of the spool 2 on the lock mechanism 6 side in the pulling direction is suppressed, and the torsion bar 21 is torsionally deformed. That is, the torsion bar 21 is twisted when the spool 2 rotates relative to the locking base 22 in the seat belt pull-out direction.

  Note that when the seat belt is completely wound by the operation of the pretensioner 5, the operation of the lock mechanism 6 by the vehicle sensor 7 may be performed as described above. Since the operation of the locking mechanism 6 by the vehicle sensor 7 is performed as described above, the locking base 22 is prevented from rotating in the pull-out direction, and the torsion bar 21 is torsionally deformed.

  While the torsion bar 21 is twisted and deformed, the spool 2 rotates in the direction in which the seat belt is pulled out, so that the force applied to the passenger from the seat belt is reduced. In this way, the torsion bar 21 can function a force limiter that absorbs the energy acting on the occupant from the seat belt when the lock mechanism 6 is activated by allowing the seat belt to be pulled out.

  Next, the stopper mechanism 8 will be described.

  The stopper mechanism 8 stops the torsion of the torsion bar 21 triggered by the operation of the pretensioner 5. Since the stopper mechanism 8 stops the torsion bar 21 from being twisted, the seat belt that restrains the occupant is restricted from being pulled out from the spool 2, so that the occupant is prevented from excessively moving. Thus, according to the stopper mechanism 8, the movement amount of the occupant can be suppressed. Moreover, the stopper mechanism 8 does not use the twist of the torsion bar 21 as a trigger, but stops the twist of the torsion bar 21 using the operation of the pretensioner 5 as a trigger. As a result, the timing for stopping the twisting of the torsion bar 21 can be set (designed) regardless of the twisting amount of the torsion bar 21, so that the degree of freedom in designing the force limiter is improved.

  As shown in FIG. 3, the stopper mechanism 8 is disposed on the side opposite to the side where the locking base 22 is disposed with respect to the torsion bar 21. Since the stopper mechanism 8 is arranged in this manner, the external shape of the retractor 1 can be made symmetrical, so that the mountability of the retractor 1 on the vehicle is improved. In the present embodiment including the pretensioner 5, the stopper mechanism 8 is disposed on the opposite side of the torsion bar 21 from the side on which the locking base 22 and the paddle wheel 51 are disposed. Improves mounting capability.

  The stopper mechanism 8 is disposed on the side opposite to the torsion bar 21 with respect to the side surface 31 of the base frame 3, and is disposed between the torsion bar 21 and the spring unit 4. Since the stopper mechanism 8 is arranged in this way, the outer shape of the retractor 1 can be made symmetrical even if the spring unit 4 is present, so that the mountability of the retractor 1 on the vehicle is improved.

  The stopper mechanism 8 includes a retainer 81, a lock cam gear 82, a clutch spring 83, an arm 84, a lock plate 85, an arm spring 86, a gear plate 87, a lock lever 88, a torsion spring 89, a spacer 90, and a plurality of screws 91.

  Further, the retractor 1 includes a transmission mechanism 9 that transmits the operation of the pretensioner 5 to the stopper mechanism 8 when the rod 52a is ejected from the pretensioner 5. For example, the illustrated retractor 1 includes a slider 93, a slider base 94, and a joint lever 92 as the transmission mechanism 9. The joint lever 92 includes an input lever 92a, an output lever 92b, and a joint shaft 92c that connects the input lever 92a and the output lever 92b.

  Next, operations of the stopper mechanism 8 and the transmission mechanism 9 will be described.

  6-8 is a figure which shows an example of the flow of operation | movement of the transmission mechanism 9 at the time of the action | operation of the pretensioner 5. FIG. FIG. 6 is a view showing a state before the rod 52 a injected from the pretensioner 5 contacts the slider 93. FIG. 7 is a view showing a state in which the rod 52 a injected from the pretensioner 5 is in contact with the slider 93. FIG. 8 is a view showing a state in which the rod 52 a ejected from the pretensioner 5 pushes out the slider 93.

  As shown in FIGS. 7 to 8, the rod 52 a moves along the pretensioner cover 53 when the pretensioner 5 is operated. The rod 52 a pushes the slider 93 in the push-out direction a from the hole formed in the pretensioner cover 53 while rotating the paddle wheel 51. The pushing direction a represents the sliding direction in which the slider 93 moves. By the pushing operation of the slider 93, the joint lever 92 rotates in the rotation direction b.

  The pushing direction “a” of the slider 93 and the rotating direction “b” of the joint lever 92 are regulated by the slider base 94. The slider base 94 is fixed and arranged inside the side surface 32 of the base frame 3.

  The slider 93 comes into contact with the input lever 92a by moving the slider 93 in the pushing direction a by contact with the rod 52a. Due to the contact with the slider 93, the input lever 92a rotates in the rotation direction b.

  FIG. 9 is an external perspective view showing a state in which the joint lever 92 rotates. As the input lever 92a rotates in the rotation direction b, the joint shaft 92c and the output lever 92b also rotate in the same rotation direction c as the rotation direction b. That is, the entire joint lever 92 rotates. By the joint lever 92, the action on the side surface 32 side of the base frame 3 moves to the side surface 31 side of the base frame 3.

  FIG. 10 is a view showing a state before the lock lever 88 is engaged with the lock cam gear 82. FIG. 11 is a view showing a state after the lock lever 88 is engaged with the lock cam gear 82. As shown in FIGS. 10 and 11, the lock lever 88 moves using the rotation of the output lever 92 b of the joint lever 92. When the output lever 92 b of the joint lever 92 rotates, the lock lever 88 rotates in the rotation direction d so as to approach the plurality of external teeth 82 a formed on the outer peripheral portion of the lock cam gear 82 by the urging force of the torsion spring 89. When the locking portion 88a of the lock lever 88 meshes with the external teeth 82a of the lock cam gear 82, the rotation of the lock cam gear 82 is prevented.

  The lock lever 88 rotates around the lever rotation shaft 90a. The lever rotation shaft 90 a is formed so as to protrude from the flat portion of the spacer 90.

  The lock cam gear 82 is an example of a second lock member that rotates together with the rotation of the spool 2 at the normal time when the stopper mechanism 8 is not operated, and prevents the rotation of the spool 2 in the seat belt pull-out direction when the stopper mechanism 8 is operated. It is. The lock cam gear 82 has a gear shaft hole 82 c that fits with the shaft 2 a of the spool 2.

  FIG. 12 is a perspective view showing an example of the lock cam gear. A spiral groove 82b is formed in the flat portion of the lock cam gear 82 shown in FIG.

  FIG. 13 is a perspective view showing an example of a stopper mechanism with a part thereof omitted. FIG. 14 is a cross-sectional view showing an example of a stopper mechanism. In FIG. 13, the lock cam gear 82 is omitted.

  The lock plate 85 has a plate shaft hole 85 c that fits with the shaft 2 a of the spool 2. In addition, an arm rotation shaft 85 a and a long hole 85 b are formed in the flat portion of the lock plate 85. The arm rotation shaft 85 a is formed so as to protrude from the flat portion of the lock plate 85. The arm 84 rotates around the arm rotation shaft 85a. A second boss 95b that protrudes from the flat portion of the second pawl 95 is inserted into the long hole 85b.

  The arm 84 is attached to the flat portion of the lock plate 85 so as to be swingable about the arm rotation shaft 85a. The arm 84 has an arm hole 84a into which the arm rotation shaft 85a is inserted. The arm 84 has an arm boss 84 b that is inserted into the groove 82 b of the lock cam gear 82. The arm boss 84 b is formed so as to protrude from the flat portion of the arm 84.

  15 to 17 are diagrams illustrating the operation of the arm 84. FIG. 15 is a view showing a state before the arm 84 operates. FIG. 16 is a diagram illustrating a state in which the arm 84 is in operation. FIG. 17 is a diagram illustrating a state after the operation of the arm 84.

  Since the locking portion 88a of the lock lever 88 meshes with the external teeth 82a of the lock cam gear 82, the rotation of the lock cam gear 82 is fixed. However, since the seat belt is pulled by the inertia of the passenger, the spool 2 rotates in the direction in which the seat belt is pulled out. Therefore, the lock plate 85 connected to the spool 2 also rotates, and the arm 84 placed on the lock plate 85 also rotates. As a result, the arm boss 84b advances in the spiral direction e along the spiral groove 82b provided inside the lock cam gear 82 (see FIG. 16). When the arm boss 84b arrives at the end point of the spiral groove 82b (see FIG. 17), the rotation of the arm 84 is fixed, so that the lock plate 85 is prevented from rotating. The timing at which the arm boss 84b of the arm 84 arrives at the end point of the groove 82b can be arbitrarily set by the length of the groove 82b of the lock cam gear 82 in the spiral direction (the length from the start point to the end point of the groove 82b). Further, the amount of twist of the torsion bar 21 can be set by the length of the groove 82b in the spiral direction.

  FIG. 18 is a diagram showing a state before the operation of the second pawl. FIG. 19 is a diagram showing a state in which the second pawl is operating. FIG. 20 is a diagram illustrating a state after the operation of the second pawl.

  Even if the rotation of the lock plate 85 is prevented by fixing the rotation of the lock cam gear 82 and the arm 84, the spool 2 further tries to rotate in the pull-out direction. Therefore, a relative rotation (rotation phase difference) occurs between the spool 2 that rotates in the pull-out direction and the lock plate 85 that is prevented from rotating. As the rotational phase difference is generated, the second pawl 95 that is swingably attached to the spool boss 2 b of the spool 2 also rotates together with the spool 2. The spool boss 2b is a protruding portion formed on the end surface portion of the spool 2 on the side where the shaft 2a protrudes. The spool boss 2 b is inserted into a swing center hole 95 a formed in the second pawl 95.

  However, the rotation of the lock plate 85 in which the second boss 95 b of the second pawl 95 is inserted into the long hole 85 b is prevented by the lock cam gear 82 and the arm 84. Therefore, the second boss 95b moves along the long hole 85b in the moving direction according to the pull-out direction of the seat belt. As a result, the second pawl 95 swings along the end surface of the lock plate 85, and the pawl tip of the second pawl 95 engages with the internal teeth 87 a formed in the opening of the gear plate 87. The second pawl 95 is directly connected to the spool 2. Accordingly, the second pawl 95 meshes with the inner teeth 87a, so that the rotation of the spool 2 is prevented, so that the twisting operation of the torsion bar 21 is stopped. When the twisting operation of the torsion bar 21 stops, the energy absorption operation stops.

  As mentioned above, although the seatbelt retractor and the seatbelt apparatus were demonstrated by embodiment, this invention is not limited to the said embodiment. Various modifications and improvements such as combinations and substitutions with some or all of the other embodiments are possible within the scope of the present invention.

1 Retractor 2 Spool 3 Base frame 4 Spring unit 5 Pretensioner 6 Lock mechanism 7 Vehicle sensor 8 Stopper mechanism 9 Transmission mechanism 21 Torsion bar 22 Locking base 51 Paddle wheel 52a Rod 82 Lock cam gear 84 Arm 84b Arm boss 85 Lock plate 88 Lock lever 87 Gear plate 92 Joint lever 93 Slider 95 Second pawl 95b Second boss 101 Seat belt device 103 Retractor 104 Seat belt 107 tongue 108 Buckle

Claims (8)

A spool that winds up the seat belt;
A base frame that rotatably accommodates the spool;
A pretensioner having a rotating body that rotates the spool in the winding direction of the seat belt during operation;
A lock mechanism having a lock member that rotates together with the rotation of the spool during normal operation and prevents rotation of the spool in the pull-out direction of the seat belt during operation;
A torsion bar that twists when the spool rotates relative to the lock member in the pull-out direction;
A stopper mechanism for stopping torsion of the torsion bar triggered by the operation of the pretensioner,
The stopper mechanism is a seat belt retractor disposed on a side opposite to a side where the lock member is disposed with respect to the torsion bar.   The seat belt retractor according to claim 1, wherein the stopper mechanism is disposed on a side opposite to a side where the rotating body is disposed with respect to the torsion bar. A spring unit that biases the spool so that the spool rotates in the winding direction;
The seat belt retractor according to claim 1 or 2, wherein the stopper mechanism is disposed between the torsion bar and the spring unit. The pretensioner has an injection body that rotates the rotating body,
The seat belt retractor according to any one of claims 1 to 3, further comprising a transmission mechanism that transmits an operation of the pretensioner to the stopper mechanism when the ejection body is injected from the pretensioner. The transmission mechanism is
A slider that slides in contact with the projectile ejected from the pretensioner;
A joint lever that rotates by contact with the slider;
The seat belt retractor according to claim 4, wherein the stopper mechanism stops twisting of the torsion bar by rotation of the joint lever. The stopper mechanism is
A lock cam gear that rotates with the spool;
The seat belt retractor according to claim 5, further comprising: a lock lever that prevents rotation of the lock cam gear by rotation of the joint lever. The stopper mechanism is
A lock plate that rotates with the spool;
A pawl having a boss inserted into a long hole formed in the lock plate and swingably attached to the spool;
An arm having a boss inserted into a groove formed in the lock cam gear and swingably attached to the lock plate;
The seat belt retractor according to claim 6, further comprising a gear plate with which the pawl is engageable.   A seat belt device comprising: the seat belt retractor according to claim 1; the seat belt; a tongue attached to the seat belt; and a buckle to which the tongue is attached and detached.

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