JP7366846B2 - Seatbelt retractor and seatbelt device - Google Patents

Description

The present disclosure relates to a seatbelt retractor and a seatbelt device including the same.

Conventionally, in a seatbelt retractor, a configuration is known in which a torsion bar is connected to a locking base by providing a flange shape at one end of the torsion bar and hooking this flange shape to the locking base (for example, Patent Document 1).

Japanese Patent Application Publication No. 2012-30636

By the way, in a seatbelt retractor, a driving member that transmits driving force from a pretensioner to a spool may be disposed between the spool and the locking base. In this case, since the distance between the spool and the locking base increases, the torsion bar connecting the two also becomes very long. If the torsion bar becomes long, the workability deteriorates and the weight increases, so there is room for improvement in the workability and weight reduction of the seat belt retractor as a whole.

An object of the present disclosure is to provide a seatbelt retractor and a seatbelt device that can improve workability and reduce weight.

A seatbelt retractor according to one aspect of an embodiment of the present invention includes a spool rotatably supported by a frame and retracting a seatbelt, and a seatbelt retractor on the spool that allows rotation of the spool when inactive, and a seatbelt on the spool when activated. a locking mechanism having a locking base that prevents rotation in the pull-out direction; a drive member that receives rotational force from the pretensioner in a direction in which the spool retracts the seat belt when the pretensioner is activated; one end is connected to the spool, and the other end is lockable with the locking base, and is twisted while being plastically deformed due to the difference in rotation between the spool and the locking base, thereby reducing the load on the seat belt. a torsion bar that absorbs and relieves occupant energy; and a connecting member that is connected to the other end of the torsion bar, extends in the axial direction of the torsion bar, and is connected to the locking base, The locking base has an annular base disposed on the other end side of the spool, and a cylindrical part extending from the center of the base toward the spool, and the driving member is connected to the spool and the spool. The torsion bar is disposed between the base portion of the locking base and radially outward of the cylindrical portion of the locking base, and when viewed from the radial direction of the spool, the torsion bar is closer to the spool than the drive member. The connecting member is inserted into the cylindrical portion and arranged to extend from the driving member to the base side.

According to the present disclosure, it is possible to provide a seatbelt retractor and a seatbelt device that can improve workability and reduce weight.

A diagram showing an example of the configuration of a seat belt device to which a seat belt retractor according to a first embodiment is applied. An exploded perspective view of the main parts of the seatbelt retractor according to the first embodiment An assembled perspective view of the main parts of the seat belt retractor shown in Figure 2 A vertical sectional view of the main parts of the seat belt retractor shown in Figures 2 and 3. Schematic diagram illustrating the effect of the first embodiment by providing a connecting member Schematic diagram showing a modification of the connection structure between the torsion bar and the connection member Schematic diagram showing a first modification of the connection structure between the connection member and the locking base. Schematic diagram showing a second modification of the connection structure between the connection member and the locking base Schematic diagram showing a third modification of the connection structure between the connection member and the locking base Schematic diagram showing a fourth modification of the connection structure between the connection member and the locking base An exploded perspective view of main parts of a seatbelt retractor according to a second embodiment A plan view of the base of the locking base in FIG. 11 viewed from the negative x direction side A plan view of the paddle wheel in FIG. 11 viewed from the negative x direction side A perspective view of the assembled state of the base and cylindrical part of the locking base in Figure 11 Side view of the assembled locking base and paddle wheel Plan view of the locking base and paddle wheel assembled, viewed from the negative x direction Schematic diagram showing the effect of the crush rib in the second embodiment A perspective view showing a modified example of the arrangement of crush ribs

Embodiments will be described below with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components in each drawing are denoted by the same reference numerals as much as possible, and redundant description will be omitted.

In the following description, the x direction, y direction, and z direction shown in each drawing after FIG. 2 are directions perpendicular to each other. The x direction is the direction of the rotation axis of the spool 11. The y direction and the z direction are respectively centrifugal directions from the rotational axis of the spool 11, and typically the z direction is the vertical direction.

[First embodiment]
A first embodiment will be described with reference to FIGS. 1 to 10. First, with reference to FIG. 1, an example of the configuration of a seat belt device 1 to which a seat belt retractor 3 according to a first embodiment is applied will be described.

The seat belt device 1 is an example of an in-vehicle system installed in a vehicle. The seat belt device 1 includes, for example, a seat belt 4, a seat belt retractor 3, a shoulder anchor 6, a tongue 7, and a buckle 8.

The seat belt 4 is an example of webbing that restrains the occupant 9 sitting on the seat 2 of the vehicle, and is a band-like member that is retractably wound around the retractor 3. A belt anchor 5 at the tip of the seat belt 4 is fixed to the seat 2 or the vehicle body near the seat 2.

The seatbelt retractor 3 is an example of a retractor that allows the seatbelt 4 to be retracted or pulled out, and when a deceleration of more than a predetermined value is applied to the vehicle, such as during a vehicle collision, the seatbelt 4 is retracted from the seatbelt retractor. Limit what can be drawn from 3. The seat belt retractor 3 is fixed to the seat 2 or the vehicle body near the seat 2.

The shoulder anchor 6 is an example of a belt insertion tool through which the seat belt 4 is inserted, and is a member that guides the seat belt 4 pulled out from the seat belt retractor 3 toward the shoulder of the occupant 9.

The tongue 7 is an example of a belt insertion tool through which the seat belt 4 is inserted, and is a component slidably attached to the seat belt 4 guided by the shoulder anchor 6.

The buckle 8 is a component to which the tongue 7 is removably locked, and is fixed to the seat 2 or the vehicle body near the seat 2, for example.

Next, the configuration of main parts of the seat belt retractor 3 according to the first embodiment will be described with reference to FIGS. 2 to 4. FIG. 2 is an exploded perspective view of main parts of the seat belt retractor 3 according to the first embodiment. FIG. 3 is an assembled perspective view of the main parts of the seat belt retractor 3 shown in FIG. 2, with a partial cross section shown. FIG. 4 is a longitudinal cross-sectional view of the main parts of the seat belt retractor 3 shown in FIGS. 2 and 3.

The seat belt retractor 3 includes a pretensioner (PT) subassembly, a shaft subassembly 10, and a locking mechanism. The main parts shown in FIGS. 2 to 4 correspond to the shaft subassembly 10.

The PT subassembly has a pretensioner mounted on the frame. The pretensioner is connected to the paddle wheel 18 (driving member) of the shaft subassembly 10, and when the pretensioner operates, the paddle wheel 18 receives rotational force from the pretensioner, which causes the spool 11 to retract the seat belt 4. Rotate in the direction.

The shaft subassembly 10 includes a spool 11 to which one end of the seat belt 4 is locked and around which the seat belt 4 is wound. The shaft subassembly 10 is rotatably mounted to the frame of the PT subassembly about an axis of rotation in the x direction. The shaft subassembly 10 also includes a torsion bar 12 that limits the load on the seat belt 4 and absorbs and relieves the energy of the occupant 9.

The locking mechanism is connected to a torsion bar 12 constituting the shaft portion of the spool 11, allows the spool 11 to rotate when it is not in operation, and prevents the spool 11 from rotating in the seat belt withdrawal direction when it is activated. The locking mechanism includes a locking subassembly, a locking base 13 shown in FIGS. 2 to 4, and the like.

Note that the basic structure of the seatbelt retractor 3, such as the PT subassembly and the locking mechanism, is well known and is disclosed in, for example, International Publication No. 2015/076377, so a detailed explanation will be omitted.

As shown in FIG. 2, the shaft subassembly 10 includes a spool 11, a torsion bar 12, a locking base 13, a connecting member 17 (also referred to as a spindle), a paddle wheel 18, a bearing plate 19, and a stopper 20. , has.

The torsion bar 12 is a rod-shaped member that limits the load applied to the seat belt and absorbs and relieves the energy of the occupant. The torsion bar 12 absorbs energy by being twisted while undergoing plastic deformation due to the difference in rotation between the spool 11 and the locking mechanism (locking base 13). The torsion bar 12 is inserted into a through hole 11A formed at the center of the axis of the spool 11, and is housed within the spool 11. The torsion bar 12 has an end 12A (one end) on the negative x direction side connected to the spool 11, and an end 12B (other end) on the positive x direction side rotatably connected to the locking base 13. . A rotating shaft 12D is provided on the negative x direction side from the end portion 12A of the torsion bar 12, and the rotating shaft 12D is formed to protrude outside from the end portion of the spool 11 on the negative x direction side. The rotating shaft 12D is fixed to the spool 11 with a push nut 22.

The locking base 13 allows the spool 11 to rotate when it is not in operation, and prevents the spool 11 from rotating in the seat belt withdrawal direction when it is in operation. The locking base 13 has a base portion 14 and a cylindrical portion 15. The base portion 14 is an annular member whose center is in the axial direction (x-axis direction) of the torsion bar 12 . The cylindrical portion 15 is fitted into the through hole 14A at the center of the base 14 from the positive x direction side and is integrally connected. The cylindrical portion 15 is provided with a through hole 15A that penetrates along the axial direction (x direction). In the locking base 13, a portion of the distal end side of the cylindrical portion 15 is inserted into the through hole 11A of the spool 11 from the x-positive side, and the base portion 14 is disposed on the x-positive side of the spool 11.

A pawl 16 is swingably installed on the base 14. The pawl 16 is activated in an emergency, protrudes radially outward from the base 14, and engages with a fixing member such as a frame, thereby locking the rotation of the spool 11 in the belt withdrawal direction.

Note that the locking base 13 may have a configuration in which the base portion 14 and the cylindrical portion 15 are integrally formed.

The end portion 12B of the torsion bar 12 is connected inside the cylindrical portion 15 of the locking base 13. Further, the end portion 12B of the torsion bar 12 is connected to the connecting member 17. A through hole 17A is provided at the center of the end of the connecting member 17 on the x direction side. A cylindrical convex portion 12C is provided further in the positive x direction from the end portion 12B of the torsion bar 12, and this convex portion 12C is inserted into the through hole 17A and fixed by a push nut 21.

The connecting member 17 is connected to the end 12B of the torsion bar 12, extends in the axial direction of the torsion bar 12, and is connected to the locking base 13. More specifically, the connecting member 17 is formed to extend in the x-positive direction from the torsion bar 12 so that the portion on the x-positive direction side is exposed to the outside from the base 14 of the locking base 13 . A flange 17B is provided in the exposed portion so as to protrude outward in the radial direction, and a rotating shaft 17C is provided so as to protrude in the positive x direction from the center position of the flange 17B. The flange 17B is locked to the end surface of the base 14 of the locking base 13 on the positive x direction side. That is, the end portion 12B of the torsion bar 12 and the connecting member 17 are inserted into the through hole 15A of the cylindrical portion 15 of the locking base 13 and connected to the locking base 13. Further, the position of the connecting member 17 in the thrust direction is regulated by contacting the locking base 13 with the flange 17B.

A paddle wheel 18 and a bearing plate 19 are also attached to the outer peripheral surface of the cylindrical portion 15 of the locking base 13. The end portion 12B of the torsion bar 12 can be locked by a locking mechanism, and rotation of the end portion 12B is stopped when the locking mechanism is activated.

In particular, in this embodiment, as shown in FIGS. 3 and 4, when viewed from the radial direction of the spool 11, the torsion bar 12 is located closer to the spool 11 than the paddle wheel 18, and the connecting member 17 is located in the cylindrical portion. 15 and arranged so as to extend from the paddle wheel 18 to the base 14 side.

In the first embodiment, the effect of providing the torsion bar 12 and the connecting member 17 in this way will be explained with reference to FIG. 5. FIG. 5 is a schematic diagram illustrating the effect of the first embodiment by providing the connecting member 17. FIG. 5(A) shows a configuration in which the conventional connecting member 17 is not provided, and FIG. 5(B) shows a configuration in which the connecting member 17 of this embodiment is provided.

In the example shown in FIG. 5, in both (A) and (B), the paddle wheel 18 as a driving member that receives rotational force from the pretensioner in the direction in which the spool 11 pulls in the seat belt 4 when the pretensioner is activated is locked with the spool 11. It is arranged between the base 14 of the base 13 and on the radially outer side of the cylindrical part 15 of the locking base 13.

Here, as shown in FIG. 5(A), conventionally, one end of the torsion bar 12 is provided with a flange shape, and this flange shape is hooked on the locking base 13 to attach the torsion bar 12 to the locking base 13. There are known configurations in which the In the case of such a connection structure between the torsion bar 12 and the locking base 13, when applied to a configuration in which the paddle wheel 18 is inserted between the spool 11 and the locking base 13, as shown in FIG. 5(A), Since the distance between the spool 11 and the locking base 13 increases, the torsion bar 12 connecting the two also becomes very long. When the torsion bar 12 becomes long, the workability deteriorates and the weight increases, so there is room for improvement in the workability and weight reduction of the seat belt retractor 3 as a whole.

In contrast, in this embodiment, as shown in FIG. 5(B), a connecting member 17 is arranged between the torsion bar 12 and the locking base 13. The torsion bar 12 is connected to a connecting member 17, and a flange 17B of the connecting member 17 is locked to the locking base 13. Thereby, even with the locking structure using the flange shown in FIG. 5, it is possible to prevent the torsion bar 12 from becoming elongated. By preventing the torsion bar from becoming elongated and eliminating the flange shape of the torsion bar 12, the shape of the torsion bar can be simplified, thereby improving workability. Furthermore, if the connecting member 17 is made of a material lighter than the material of the torsion bar 12, the weight of the seat belt retractor 3 as a whole can be reduced. As a result, the seat belt retractor 3 according to this embodiment can improve workability and reduce weight.

The material of the torsion bar 12 is, for example, iron. The material of the connecting member 17 is, for example, aluminum. The locking base 13 is made of a conventional material with relatively low hardness, such as zinc die-casting, but a high hardness material, such as carbon steel, is used.

In addition, conventional methods for connecting the locking base 13 and torsion bar 12 include a method that does not involve deformation of the locking base 13, such as the method of locking with a flange of this embodiment, and a method that does not involve deformation of the locking base 13. Techniques are also known in which the torsion bar 12 is fastened to the locking base 13 by caulking or the like, or the end of the torsion bar 12 is press-fitted into the locking base 13. In the case of these other methods, since it is not necessary to extend the end of the torsion bar 12 to the outside of the locking base 13, the above-mentioned lengthening problem is unlikely to occur. However, in these other methods, it is necessary to deform the locking base 13 side for fastening, so it is preferable that the material of the locking base 13 is softer than the material of the torsion bar 12. On the other hand, in this embodiment, a locking method using a flange is applied instead of such other connection methods, and the reason for this will be explained below.

In this embodiment, as shown in FIGS. 2 to 4, a stopper 20 is provided inside the shaft subassembly 10 and around the outer peripheral surface of the torsion bar 12. The stopper 20 is an element for stopping the torsional rotation of the torsion bar 12 at a predetermined rotation speed to prevent the torsion bar 12 from breaking due to excessive twisting. In a configuration in which such a stopper 20 is provided, the external force that the locking base 13 receives is generally large when the locking mechanism operates, so in order to increase the strength of the locking base 13, a material that is relatively harder than conventional general materials is used. is often used. In this case, since the locking base 13 has a higher hardness than the torsion bar 12, it is difficult to deform the locking base 13 and fasten the torsion bar 12 as in the other methods described above, and a locking method using a flange has to be used. I don't get it.

Therefore, in the case of a configuration in which the stopper 20 for restricting the torsional rotation of the torsion bar 12 is provided as in this embodiment, the locking base 13 is necessarily formed of a high hardness material, and a flange is connected to the torsion bar 12. A locking method will be used. In this case, as shown in FIG. 5 etc., due to the structure of the connection, it is necessary to extend the torsion bar 12 until it penetrates the locking base 13, so a connection member 17 is inserted between the locking base 13 and the torsion bar 12. Intervention is particularly effective. Note that, unlike this embodiment, even if the stopper 20 is not provided, the locking base 13 is not made of a high-hardness material, or the torsion bar 12 and the locking base 13 are locked with a flange. For example, the same effects as this embodiment can be achieved.

Further, the above-mentioned locking method using a flange (hereinafter also referred to as "hook structure") has the following advantages over other connection methods such as caulking. When adopting a caulking structure, (1) the material of the locking base must allow deformation due to caulking, and (2) the caulking process is performed after inserting the torsion bar into the locking base. There are limitations such as the need for caulking equipment on the assembly line. On the other hand, in the case of a hook structure, the torsion bar can be inserted or lightly press-fitted until the flange comes into contact with the locking base while maintaining the part shape, so the material of the locking base does not matter and there is no need for crimping equipment. Become. Furthermore, the hook structure has higher strength than the caulking structure when an axial load is applied to the fastening portion.

Further, although increasing the length of the torsion bar 12 is a problem that should be avoided, if the torsion bar 12 is too short, there is a risk that the desired torsional rotation speed may not be achieved. For this reason, it is better not to shorten the torsion bar 12 arbitrarily. For example, when viewed from the radial direction of the spool 11, the tip of the other end of the torsion bar 12 (in the examples of FIGS. 2 to 4, the tip position of the convex portion 12C) is located at the end surface of the paddle wheel 18 on the spool 11 side. It is preferable to arrange it so that it is located at the same position. With this configuration, the torsion bar 12 can be sufficiently twisted and rotated to realize a sufficient energy absorption function, and the seat belt retractor 3 can also be improved in workability and reduced in weight.

Further, the connecting portion between the end portion 12B of the torsion bar 12 and the connecting member 17 (the portion including the through hole 17A, the push nut 21, the convex portion 12C, etc. of the connecting member 17) is, for example, as shown in FIG. 5(B). It is preferable that the spool 11 be disposed inside the spool 11. Thereby, the axial dimension of the shaft subassembly 10 can be shortened.

FIG. 6 is a schematic diagram showing a modification of the connection structure between the torsion bar 12 and the connection member 17. As described with reference to FIG. 5 and the like, in the above embodiment, the cylindrical convex portion 12C provided at the other end of the torsion bar 12 is inserted into the through hole 17A provided in the connecting member 17 and fixed. In other words, the torsion bar 12 side has a convex shape and the connecting member 17 side has a concave shape. This unevenness relationship may be replaced. For example, as shown in FIG. 6, a hole 12E is provided along the axial direction on the end surface of the torsion bar 12, a cylindrical convex portion 17D is provided on the end surface of the connecting member 17, and the convex portion 17D is connected to the hole 12E. A structure in which they are fixed together may be used.

Furthermore, the connection structure between the torsion bar 12 and the connection member 17 can be achieved by any method such as fixation with screws or press-fit fixation by caulking, in addition to fastening with a fastening member such as the push nut 21 as in the above embodiment. method may be applied. Further, if the end surfaces are bonded together using an adhesive, it is not necessary to form holes or protrusions on the end surfaces, so that workability can be further improved.

7 to 10 are schematic diagrams showing first to fourth modifications of the connection structure between the connection member 17 and the locking base 13. The connecting member 17 is connected to the locking base 13 by a method that does not involve deformation of the locking base 13. In the embodiment described above, a locking method using the flange 17B is illustrated as an example of a specific connection structure, but other methods may be used.

For example, as in a first modification shown in FIG. 7, a configuration may be adopted in which a taper 17E protruding from the outer peripheral side of the connecting member 17 is provided and the connecting member 17 is locked to the locking base 13 by the taper 17E. In addition, as in a second modification shown in FIG. 8, a screw hole 13A is provided in the locking base 13 that passes through the outer circumferential surface along the radial direction to the through hole 15A on the axis side, and the screw hole 13A is provided on the radially outer side. A configuration may also be adopted in which the set screw 13B is screwed together and advanced into the inner circumferential surface of the through hole 15A, and the outer circumferential surface of the connecting member 17 is fixed with the tip of the set screw 13B. Further, as in a third modification shown in FIG. 9, a female threaded portion 13C is provided on the inner peripheral surface of the through hole 15A of the locking base 13, a male threaded portion 17F is provided on the outer peripheral surface of the connecting member 17, and the female threaded portion 13C and the male thread are provided on the outer peripheral surface of the connecting member 17. It may be configured to be connected by screwing with the portion 17F. Further, as in the fourth modification shown in FIG. 10, the locking base 13 is provided with an insertion hole 13D extending in the radial direction, the connecting member 17 is also provided with a through hole 17G passing through in the radial direction, and these insertion holes 13D are provided. Alternatively, the pin 13E may be inserted into the through hole 17G for connection.

[Second embodiment]
The second embodiment will be described with reference to FIGS. 11 to 18. FIG. 11 is an exploded perspective view of the main parts of the seatbelt retractor 3 according to the second embodiment. FIG. 12 is a plan view of the base portion 14 of the locking base 13 in FIG. 11, viewed from the negative x direction side. FIG. 13 is a plan view of the paddle wheel 18 in FIG. 11 viewed from the negative x direction side. FIG. 14 is a perspective view of the locking base 13 in FIG. 11 in which the base portion 14 and the cylindrical portion 15 are assembled. FIG. 15 is a side view of the locking base 13 and paddle wheel 18 assembled together. FIG. 16 is a plan view of the assembled state of the locking base 13 and paddle wheel 18 viewed from the negative x direction side.

Note that, among the components of the seat belt retractor 3 of the second embodiment, other than the elements illustrated in FIG. Since the configuration is similar to that of the first embodiment, the explanation will be omitted.

As shown in FIG. 11, the base portion 14 and the cylindrical portion 15 of the locking base 13 are formed as separate parts. The cylindrical portion 15 is made of a high hardness material that is relatively hard compared to other parts of the seat belt retractor 3 such as the base 14 and the spool 11, and examples of such high hardness material include carbon. Steel is an example. On the other hand, the base portion 14 is formed of a low-hardness material that is relatively lower in hardness than the cylindrical portion 15, and examples of such a material include zinc die-casting. With this configuration, the entire locking base 13 is not made of a high-hardness material, and the base 14, which is not required to have high hardness, can be made of a low-hardness material, so that the hardness requirements of the locking base 13 can be met, and the manufacturing cost is reduced. can be suppressed. Further, it is preferable that the material of the base portion 14 has low hardness and is relatively lightweight with respect to the cylindrical portion 15. Thereby, the effect of reducing the weight of the locking base 13 and the seat belt retractor 3 can also be achieved.

As shown in FIGS. 11 and 14, the locking base 13 is formed by fitting the cylindrical portion 15 into the through hole 14A at the center of the base 14 from the positive x direction side and connecting it integrally. The circumferential surface 15B of the cylindrical portion 15 on the negative x direction side is formed in a polygonal shape (hexagonal shape in the example of FIG. 11). On the other hand, the inner circumferential surface of the through hole 14A is formed in the same polygonal shape as the circumferential surface 15B so that the circumferential surface 15B can fit therein. When the cylindrical portion 15 is fitted to the base 14, a part of the polygonal peripheral surface 15B is exposed from the base 14 in the negative x direction, as shown in FIG.

As shown in FIGS. 11, 13, and 14, a through hole 18A is provided in the center of the paddle wheel 18, and by fitting the cylindrical portion 15 into the through hole 18A, locking is achieved as shown in FIG. It is integrally connected to the base 13. This through hole 18A is formed in a polygonal shape similar to the circumferential surface 15B so that it can be engaged with the circumferential surface 15B of the cylindrical portion 15.

As shown in FIGS. 14 and 16, the locking base 13 is provided with a crush rib 14B at a position facing the paddle wheel 18 in the radial direction. As shown in FIGS. 11 and 12, the crush rib 14B is formed integrally with the base 14 and is provided so as to protrude from the base 14 onto the circumferential surface 15B of the cylindrical portion 15. The crush rib 14B is arranged at the polygonal periphery of the through hole 14A of the base 14 when viewed from the x direction.

The paddle wheel 18 (driving member) is made of the same high-hardness material as the cylindrical portion 15 of the locking base 13. On the other hand, since the crush ribs 14B of the locking base 13 are formed integrally with the base 14, they are made of a low hardness material like the base 14. Therefore, when connecting the paddle wheel 18 to the locking base 13, the crush rib 14B is press-fitted into the gap between the through hole 18A of the paddle wheel 18 and the circumferential surface 15B of the cylindrical part 15, so that the locking base 13 and the paddle The connection with the wheel 18 can be made stronger. In order to achieve the effect of the crush rib 14B, the material of the crush rib 14B should have a hardness that can be press-fitted into the gap between the paddle wheel 18 and the cylindrical portion 15.

The crush rib 14B is provided so as to be shifted in the direction opposite to the driving force generation direction. More specifically, as shown in FIGS. 12, 16, etc., the crush ribs 14B are arranged on three sides of the six hexagonal sides of the circumferential surface 15B of the cylindrical portion 15 with one side spaced apart. Furthermore, it is shifted from the midpoint of each side to the side opposite to the driving force generation direction (clockwise in the examples of FIGS. 12 and 16).

On the other hand, as shown in FIG. 13, FIG. 14, and FIG. Three recesses 18B are formed to be recessed outward in the circumferential direction.

The effect of arranging the crush ribs 14B as described above will be described with reference to FIG. 17. FIG. 17 is a schematic diagram showing the effects of the crush rib 14B in the second embodiment.

First, in the initial state, the inner peripheral surface of the through hole 18A of the paddle wheel 18 is in contact with the crush rib 14B of the locking base 13. Next, when the pretensioner of the seatbelt retractor 3 operates, the paddle wheel 18 receives a driving force around the x-axis. Next, the paddle wheel 18 rotates relative to the cylindrical portion 15 of the locking base 13 in the driving force generation direction (clockwise in the example of FIG. 17) due to the received driving force.

As a result of this relative rotation, as shown in FIG. The shaped portions 15 are fixed to each other via the three crush ribs 14B and the six apex portions 15C, and relative rotation between the paddle wheel 18 and the cylindrical portion 15 is stopped. As a result, the parts of the rocking base 13 and the paddle wheel 18 can be fixed to each other, the deviation of the axes of the rocking base 13 and the paddle wheel 18 can be restricted, and the rotational phase between the rocking base 13 and the paddle wheel 18 can be controlled. Discrepancies can also be regulated. As a result, the connection and centering between the locking base 13 and the paddle wheel 18 are completed.

In this way, by providing the crush ribs 14B shifted in the direction opposite to the driving force generation direction, parts can be fixed between the paddle wheel 18 on the upstream side of driving force transmission and the locking base 13 on the downstream side. Axis center regulation and rotational phase regulation can be ensured, and loss and variation in driving force transmission can be prevented.

FIG. 18 is a perspective view showing a modification of the arrangement of crush ribs. In the second embodiment, it is sufficient that a crush rib is provided at the connecting portion between the rocking base 13 and the paddle wheel 18, and the crush rib 14B as shown in FIGS. A configuration other than integrally formed may also be used.

For example, as shown in FIG. 18, a crush rib 19B may be provided on the bearing plate 19 (annular member). As shown in FIGS. 2, 18, etc., the bearing plate 19 is disposed on the spool 11 side of the paddle wheel 18 and on the radially outer side of the cylindrical portion 15 of the locking base 13, and is made of the same low hardness material as the base 14. is formed. As shown in FIG. 18, the bearing plate 19 has a crush which projects from the bearing plate 19 in the x positive direction so as to be able to enter the gap between the cylindrical portion 15 and the paddle wheel 18, and which is integrally formed with the bearing plate 19. Ribs 19B are provided.

A through hole 19A is provided in the center of the bearing plate 19, and the cylindrical portion 15 is fitted into the through hole 19A to be integrally connected to the locking base 13 and the paddle wheel 18. The crush rib 19B is arranged at the periphery of the through hole 19A when viewed from the x direction. The crush rib 19B is press-fitted into the gap between the circumferential surface 15B of the cylindrical portion 15 and the through hole 18A of the paddle wheel 18 with the paddle wheel 18 and the bearing plate 19 engaged with the cylindrical portion 15 of the locking base 13. Thereby, the connection between the locking base 13, the paddle wheel 18, and the bearing plate 19 can be made stronger.

The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Design changes made by those skilled in the art as appropriate to these specific examples are also included within the scope of the present disclosure as long as they have the characteristics of the present disclosure. The elements included in each of the specific examples described above, their arrangement, conditions, shapes, etc. are not limited to those illustrated, and can be changed as appropriate. The elements included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

1 Seatbelt device 3 Seatbelt retractor 4 Seatbelt 7 Tang 8 Buckle 10 Shaft subassembly 11 Spool 12 Torsion bar 13 Locking base 14 Base 14B, 19B Crush rib 15 Cylindrical part 15A Through hole 17 Connecting member 17B Flange 18 Paddle wheel ( drive member)
19 Bearing plate (annular member)

Claims (12)

a spool that is rotatably supported by the frame and that winds up the seat belt;
a locking mechanism having a locking base that allows rotation of the spool when inactive and prevents rotation of the spool in the seat belt withdrawal direction when activated;
a drive member that receives rotational force from the pretensioner in a direction in which the spool draws in the seat belt when the pretensioner is activated;
Built in the spool, one end is connected to the spool, the other end is lockable with the locking base, and is twisted while being plastically deformed due to a rotation difference between the spool and the locking base. , a torsion bar that absorbs and alleviates occupant energy by limiting the load applied to the seat belt;
a connecting member connected to the other end of the torsion bar, extending in the axial direction of the torsion bar and connected to the locking base;
Equipped with
The locking base has an annular base disposed on the other end side of the spool, and a cylindrical part extending from the center of the base toward the spool, and the driving member is connected to the spool. disposed between the base of the locking base and the radially outer side of the cylindrical portion of the locking base;
When viewed from the radial direction of the spool, the torsion bar is located closer to the spool than the driving member, and the connecting member is inserted into the cylindrical portion and extends from the driving member to the base side. arranged like this,
Seatbelt retractor. a connecting portion between the other end of the torsion bar and the connecting member is arranged inside the spool;
The seat belt retractor according to claim 1. The tip of the other end of the torsion bar is located at a position of the spool-side end surface of the drive member when viewed from the radial direction of the spool.
The seat belt retractor according to claim 1 or 2. The connecting member is connected to the locking base in a manner that does not involve deformation of the locking base.
The seat belt retractor according to any one of claims 1 to 3. An end of the connecting member opposite to the torsion bar is disposed to protrude outward from the base of the locking base, and is brought into contact with the locking base by a flange provided at the end, thereby providing thrust in the thrust direction. location is regulated,
The seat belt retractor according to claim 4. the cylindrical portion of the locking base has a through hole in the axial direction;
The seat belt retractor according to any one of claims 1 to 5. comprising a stopper for regulating the torsional rotation speed of the torsion bar when absorbing energy;
The seat belt retractor according to any one of claims 1 to 6. The base portion and the cylindrical portion of the locking base are formed as separate parts,
The cylindrical portion is formed of a high hardness material, and the base portion is formed of a low hardness material.
The seat belt retractor according to any one of claims 1 to 7. The driving member is made of the same high hardness material as the cylindrical part,
The locking base is provided with a crush rib at a position facing the drive member in the radial direction,
The crush rib is formed integrally with the base, and is provided so as to protrude from the base onto the circumferential surface of the cylindrical part.
The seat belt retractor according to claim 8. an annular member disposed on the spool side of the driving member and on the radially outer side of the cylindrical portion of the locking base and made of the same low hardness material as the base;
The annular member is provided with a crush rib that protrudes so as to be able to enter a gap between the cylindrical portion and the drive member and is integrally formed with the annular member.
The seat belt retractor according to claim 7 or 8. The crush rib is provided to be shifted in a direction opposite to the driving force generation direction.
The seat belt retractor according to claim 9 or 10. Seat belts that restrain the occupants,
The seat belt retractor according to any one of claims 1 to 11, which retracts the seat belt so that the seat belt can be pulled out, and operates in an emergency to prevent the seat belt from being pulled out.
a tongue slidably supported by the seat belt pulled out from the seat belt retractor;
a buckle provided on a vehicle body or a vehicle seat, to which the tongue is removably locked;
A seat belt device comprising:

Images