Retractor and seatbelt device

Abstract

The invention provides a retractor and a seatbelt device capable of reducing generation of vibration sound. A retractor (1) according to one embodiment of the present invention is provided with a lock mechanism (4) that restricts the rotation of a spool (2), and the lock mechanism (4) is provided with: a lock gear (41) that is disposed coaxially with the spool (2) so as to be rotatable relative to the spool (2); and a flywheel (43) that is disposed on the lock gear (41) and moves the pawl (42) by the relative rotation of the spool (2) and the lock gear (41). The flywheel (43) has a protrusion (43f) disposed at the tip in the relative rotation direction (R). The lock gear (41) has a stopper (41i) which is configured so as to be in contact with the protrusion (43f) when the flywheel (43) is not in operation, thereby tilting the posture of the flywheel (43), and to release the contact with the protrusion (43f) when the flywheel (43) is in operation.

Description

Technical Field

[0001] The present invention relates to a retractor and a seat belt device, and more particularly to a retractor and a seat belt device capable of reducing the generation of vibration sound. Background Art

[0002] In vehicles such as automobiles, a seat belt device is generally provided to restrain an occupant to a seat, wherein the seat has a seat portion for the occupant to sit on and a backrest portion located at the back of the occupant. The seat belt device includes a webbing for restraining the occupant, a retractor for winding the webbing, a buckle disposed on the side of the seat, and a tongue disposed on the webbing. The tongue is fitted into the buckle to restrain the occupant to the seat using the webbing.

[0003] Most of these retractors include: a reel for winding the webbing; a base frame for rotatably housing the reel; a spring unit for applying a winding force to the reel; a vehicle sensor for detecting a sudden deceleration of the vehicle; a locking mechanism that operates through the vehicle sensor to engage the reel with the base frame; and a pretensioner for removing slack from the webbing in an emergency such as a vehicle collision.

[0004] For example, Patent Document 1 discloses a block device having a control disk as a part of a locking mechanism. An inertial mass body that can rotate around a rotation axis is arranged on the control disk. In the invention described in Patent Document 1, in order to reduce the noise (vibration sound) generated by the inertial mass body, an L-shaped protrusion that abuts against a contact surface formed on the outer edge of the inertial mass body is arranged. In addition, the control disk is sometimes referred to as a locking gear, and the inertial mass body is referred to as a flywheel.

[0005] Prior art literature

[0006] Patent Document 1: Japanese Patent No. 5545910 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, if the protrusion is brought into contact with the inertial mass body (flywheel) as described in Patent Document 1, it becomes a major factor that hinders the rotational motion of the inertial mass body (flywheel), so a large gap needs to be set in advance. Therefore, this gap becomes a major factor that generates vibration sound.

[0009] The present invention has been made in view of the above problem, and an object of the present invention is to provide a retractor and a seat belt device capable of reducing the generation of vibration noise.

[0010] Means for solving problems

[0011] According to the present invention, a retractor is provided, comprising: a spool, which winds up a seat belt for restraining an occupant; a base frame, which rotatably accommodates the spool; and a locking mechanism, which limits the rotation of the spool, wherein the retractor is characterized in that the locking mechanism comprises: a locking gear, which is coaxially arranged with respect to the spool so as to be relatively rotatable; a pawl, which is arranged so as to be engageable with the base frame; a flywheel, which is arranged on the locking gear, and the pawl is moved by relative rotation of the spool and the locking gear; and a hook spring, which applies a force to the flywheel in a direction opposite to the relative rotation direction during operation, the flywheel having a protrusion arranged at the front end in the relative rotation direction, the locking gear having a stopper, and the stopper is configured to contact with the protrusion when not in operation to tilt the posture of the flywheel, and release the contact with the protrusion when in operation.

[0012] The stopper may have a tapered surface at a portion that contacts the protrusion.

[0013] The stopper may include: a support portion formed on the lock gear; and a protrusion portion formed to be contactable with an upper portion of the protrusion.

[0014] The projection may have a curved surface at a portion that contacts the stopper.

[0015] The flywheel may be configured to be supported at three points by the lock gear when not in operation.

[0016] Alternatively, the locking gear may include: a rotating shaft for supporting the flywheel in a rotatable manner; a plurality of engaging claws arranged on the outer periphery of the rotating shaft; and a guide portion formed along the outer periphery of the root of the rotating shaft, and the flywheel may include: a through hole for inserting the rotating shaft; and an engaging hole for engaging the engaging claw, and the flywheel may be configured to be supported by the stopper, the engaging claw and the guide portion when not in operation.

[0017] The hook spring may be arranged to bias the protrusion in a direction to make it contact with the stopper when not in operation.

[0018] According to the present invention, there is provided a seat belt device characterized by comprising a retractor having any one of the above-mentioned structures.

[0019] Effects of the Invention

[0020] According to the retractor and seat belt device of the present invention, when the flywheel is not working, the protrusion formed on the flywheel is brought into contact with the stopper formed on the locking gear to tilt the flywheel, thereby filling the gap in the flywheel required when the flywheel is working, and reducing the vibration sound generated by the retractor and seat belt device when not working. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a developed view showing a retractor according to an embodiment of the present invention.

[0022] Figure 2 It means assembling the flywheel on Figure 1 A top view of the state of the locking gear is shown.

[0023] Figure 3 yes Figure 2 The sectional views of the components shown are: (A) is a sectional view taken along the arrow AA, and (B) is a sectional view taken along the arrow BB.

[0024] Figure 4 yes Figure 2 The sectional views of the components shown are: (A) is a sectional view taken along the arrow CC, and (B) is a sectional view taken along the arrow DD.

[0025] Figure 5 It is a top view showing the movement of the flywheel during operation.

[0026] Figure 6 It is a diagram showing the overall configuration of a seat belt device according to one embodiment of the present invention. DETAILED DESCRIPTION

[0027] Below, use Figure 1 to Figure 6 Here, the embodiments of the present invention are described. Figure 1 It is a developed view showing a retractor according to an embodiment of the present invention. Figure 2 It means assembling the flywheel on Figure 1 The top view of the locked gear shown in FIG. Figure 1 In the figure, for the convenience of explanation, the figure of the ribbon is omitted.

[0028] like Figure 1 and Figure 2 As shown, a retractor 1 of one embodiment of the present invention comprises: a reel 2, which is wound around a webbing for restraining an occupant; a base frame 3, which accommodates the reel 2 in a rotatable manner; and a locking mechanism 4, which limits the rotation of the reel 2, and the locking mechanism 4 comprises: a locking gear 41, which is coaxially arranged with respect to the reel 2 in a rotatable manner; a pawl 42, which is arranged in a manner capable of engaging with the base frame 3; a flywheel 43, which is arranged on the locking gear 41, and the pawl 42 is moved by the relative rotation of the reel 2 and the locking gear 41; a hook spring 44, which applies force to the flywheel 43 in a direction opposite to the relative rotation direction during operation; and a locking base 45, which is arranged between the reel 2 and the locking gear 41.

[0029] The spool 2 is a drum around which the webbing is wound, and one end of the spool 2 is rotatably supported by the spring unit 5, for example, and the other end is connected to the lock base 45. The lock base 45 is rotatably supported by the holder cover 6 via a cap 46 (bearing).

[0030] The spring unit 5 is a member that urges the spool 2 in the winding direction and has a coil spring built in. The holder cover 6 is a member that accommodates the lock mechanism 4 and the vehicle sensor 47. The spring unit 5 and the holder cover 6 are fixed to the base frame 3 directly or indirectly.

[0031] In addition, the retractor 1 may also include a pretensioner 7 for removing slack in the webbing in an emergency such as a vehicle collision. For example, the pretensioner 7 includes a tube 71 capable of releasing a mass body, a gas generator 72 disposed at the rear end of the tube 71, and a ring gear 73 rotated by the mass body released from the tube 71 by the operation of the gas generator 72.

[0032] The pretensioner 7 is disposed, for example, inside the base frame 3 adjacent to the lock base 45 . Alternatively, the pretensioner may be disposed outside the base frame 3 adjacent to the lock base 45 or inside the spring unit 5 .

[0033] The base frame 3 is, for example, a frame structure having a substantially square U-shaped cross section, and a pair of wall members constituting the side surfaces are formed at both ends of the wall member constituting the back surface. An opening through which the end of the reel 2 (including the locking base 45) is inserted is formed in the pair of wall members constituting the side surfaces, and engaging teeth 31 are formed on the inner circumferential surface. In addition, a pad constituting the front surface may be connected to the front end of the pair of wall members constituting the side surfaces.

[0034] The locking mechanism 4 is a mechanism for limiting the pulling out of the webbing in an emergency such as a vehicle collision. The locking mechanism 4 is composed of components such as a locking gear 41, a ratchet 42, a flywheel 43, a locking base 45, a cover 46, and a vehicle sensor 47. In addition, the locking mechanism 4 is not limited to the structure shown in the figure.

[0035] The locking base 45 is a substantially disc-shaped member connected to the end of the reel 2. The locking base 45 is inserted through the opening of the base frame 3 and is arranged so that the outer periphery is opposite to the engaging teeth 31. The locking base 45 has a thickness capable of accommodating the pawl 42, and a receiving portion 45a constituting a space capable of accommodating the pawl 42 is formed on a part of the outer periphery. In addition, the locking base 45 has a shaft portion 45b constituting the rotation axis of the reel 2.

[0036] The vehicle sensor 47 includes, for example, a spherical mass body 47a, a sensor rod 47b that swings due to the movement of the mass body 47a, and a sensor cover 47c that accommodates the mass body 47a and the sensor rod 47b. When the vehicle body of the vehicle sensor 47 decelerates or tilts by a predetermined value or more, the balance of the mass body 47a is destroyed, the sensor rod 47b is pushed upward, and the front end of the sensor rod 47b engages with the lock gear 41, thereby restricting the rotation of the lock gear 41.

[0037] When the lock gear 41 rotates relative to the spool 2 (lock base 45), the pin 42a of the ratchet 42 moves along the guide groove 41d, and the front end is pushed out radially from the side of the lock base 45, and the engaging claw formed at the front end engages with the engaging tooth 31 of the base frame 3. Through this engagement, the rotation of the spool 2 is locked, and the pulling out of the webbing is restricted. In addition, the ratchet 42 is urged radially inward by a ratchet spring (not shown) so that the front end (engaging claw) does not protrude radially outward from the side of the lock base 45.

[0038] The lock gear 41 includes, for example, a disk portion 41a constituting a plane arranged to face the lock base 45, an outer peripheral wall 41b erected toward the outside along the outer edge of the disk portion 41a, and a center portion 41c through which the shaft portion 45b of the lock base 45 is inserted. An engagement tooth 41g capable of engaging with the sensor rod 47b of the vehicle sensor 47 is formed on the outer peripheral surface of the outer peripheral wall 41b.

[0039] The disc portion 41a is formed with a guide groove 41d for guiding the pin 42a of the ratchet pawl 42, a rotary shaft 41e for rotatably supporting the flywheel 43, a plurality of engaging claws 41f arranged on the outer periphery of the rotary shaft 41e, and a guide portion 41h formed along the outer periphery of the base of the rotary shaft 41e (see Figure 3 ) etc. The flywheel 43 is arranged in the space formed by the disk portion 41a and the outer peripheral wall 41b. In addition, a plurality of protrusions for defining the space for accommodating the flywheel 43 may be formed on the surface of the disk portion 41a.

[0040] The flywheel 43 has a shape that is bent or folded, for example, so as to be inserted into a space surrounded by the disc portion 41a, the outer peripheral wall 41b and the center portion 41c of the locking gear 41, and has a first end 43a located on the upstream side in the relative rotation direction R and a second end 43b located on the downstream side in the relative rotation direction R.

[0041] In addition, the flywheel 43 has, for example: an insertion hole 43c formed in the middle part between the first end 43a and the second end 43b, for the rotation shaft 41e of the locking gear 41 to be inserted; a plurality of engaging holes 43d arranged along the outer periphery of the insertion hole 43c, for the engaging claws 41f of the locking gear 41 to be engaged; and an annular protrusion 43e arranged along the guide portion 41h of the locking gear 41.

[0042] The engagement hole 43d is configured to restrict the axial movement of the engagement claw 41f and allow the rotational movement of the engagement claw 41f when engaging with the engagement claw 41f. In addition, the relative rotation amount of the flywheel 43 is restricted by the circumferential length of the engagement hole 43d. In addition, by making the guide portion 41h guide the convex portion 43e, the relative rotation of the flywheel 43 can be stabilized.

[0043] In addition, the flywheel 43 has a protrusion 43f disposed at the front end in the relative rotation direction R. The protrusion 43f is formed, for example, along the extending direction of the first end 43a. The protrusion 43f has a curved surface 43g on the surface of the flywheel 43 on the side opposite to the relative rotation direction R or on the side close to the outer peripheral wall 41b of the lock gear 41.

[0044] The lock gear 41 has a stopper 41i which is configured to contact with the protrusion 43f to tilt the posture of the flywheel 43 when the flywheel 43 is not in operation, and to release the contact with the protrusion 43f when the flywheel 43 is in operation.

[0045] The plurality of engagement claws 41f include, for example, a first engagement claw 41j disposed on the first end 43a side of the flywheel 43 across the rotary shaft 41e and a second engagement claw 41k disposed on the second end 43b side of the flywheel 43. The engagement claws 41f may include engagement claws other than the first engagement claws 41j and the second engagement claws 41k.

[0046] The flywheel 43 is formed in a direction substantially orthogonal to the first end 43a and the second end 43b, and has an insertion hole 43c substantially at its center. The first engaging claw 41j and the second engaging claw 41k are arranged to face each other on an extension line extending from the insertion hole 43c toward the second end 43b.

[0047] The hook spring 44 is inserted into, for example, a support shaft 44a formed between the flywheel 43 and the center portion 41c (see Figure 3 ). The support shaft 44a may be formed on the lock gear 41 side or on the flywheel 43 side. In addition, the hook spring 44 is configured to apply force in a direction in which the protrusion 43f contacts the stopper 41i when not in operation.

[0048] Reference Figure 3 (A)~ Figure 4(B) will now explain the structure of the protrusion 43f of the flywheel 43 and the stopper 41i of the lock gear 41. Figure 3 yes Figure 2 The sectional views of the components shown are: (A) is a sectional view taken along the arrow AA, and (B) is a sectional view taken along the arrow BB. Figure 4 yes Figure 2 The sectional views of the components shown are: (A) is a sectional view taken along the arrow CC, and (B) is a sectional view taken along the arrow DD.

[0049] like Figure 3 As shown in (A), the stopper 41i is formed into a hook shape having a support portion 41m erected from the lock gear 41 and a protrusion 41n formed to be able to contact the upper part of the protrusion 43f. The lower surface of the protrusion 41n constitutes a surface in contact with the protrusion 43f, and has a tapered surface 41p at the portion in contact with the protrusion 43f.

[0050] In addition, the projection 43f may have a curved surface 43g at a portion that contacts the tapered surface 41p of the stopper 41i. Figure 3 The protrusion 43f shown in (A) has an inclined surface on the upper side, but the protrusion 43f only needs to have a curved surface 43g with a rounded corner at least at the front end (the end on the opposite side of the relative rotation direction R). The curved surface 43g is not limited to the shape shown in the figure as long as it can move smoothly along the tapered surface 41p.

[0051] like Figure 3 As shown in (B), when the flywheel 43 is not in operation, that is, when the protrusion 43f is pressed against the tapered surface 41p of the stopper 41i, the protrusion 43f sinks in a manner close to the disc portion 41a of the lock gear 41, and the posture of the flywheel 43 becomes a state of inclination at an angle α. At this time, a part of the convex portion 43e of the flywheel 43 (the part on the side where the protrusion 43f is formed) is pressed against the guide portion 41h of the lock gear 41, and the flywheel 43 constitutes a fulcrum of inclination.

[0052] like Figure 2 As shown, the flywheel 43 can be divided into a Down side (right side in the figure) close to the disc portion 41a of the lock gear 41 and an Up side (left side in the figure) away from the disc portion 41a of the lock gear 41 across a straight line L passing through the contact point between the convex portion 43e and the guide portion 41h when not in operation. The first engaging claw 41j and the second engaging claw 41k can also be arranged in a manner opposite to each other along the straight line L.

[0053] Figure 4 As shown in (A) Figure 2 The CC-direction cross-sectional view shows a cross section through the first engaging claw 41j. Figure 4 (B) Figure 2The DD-view cross-sectional view shows a cross section through the second engaging claw 41k. Figure 4 (A) and Figure 4 As shown in FIG. 5B , when the flywheel 43 is not in operation, that is, when the projection 43 f is pressed against the tapered surface 41 p of the stopper 41 i , the surface of the flywheel 43 is pressed against the first engagement claw 41 j and the second engagement claw 41 k .

[0054] Therefore, when the flywheel 43 is not in motion, it is supported by the stopper 41i, the engaging claws 41f (the first engaging claw 41j and the second engaging claw 41k) and the guide portion 41h. Figure 2 The back side of the flywheel 43 on the straight line L shown (the contact point between the protrusion 43e and the guide portion 41h) serves as a fulcrum, and is supported by the locking gear 41 at three points through a point on the surface on the Down side of the straight line L (the contact point between the protrusion 43f and the stopper 41i) and two points on the surface on the Up side of the straight line L (the contact point between the first engaging claw 41j and the second engaging claw 41k and the flywheel 43).

[0055] Here, Figure 5 The flywheel 43 is configured to relatively rotate in the relative rotation direction R when the webbing is pulled out faster than normal, and the second end portion 43 b is engaged with the internal teeth formed on the retainer cover 6 .

[0056] At this time, if Figure 5 As shown, through the relative rotation of the flywheel 43, the protrusion 43f moves in the direction away from the stopper 41i, and the protrusion 43f moves along the tapered surface 41p of the stopper 41i, and finally the contact between the protrusion 43f and the stopper 41i is released.

[0057] As the flywheel 43 (protrusion 43f) rotates relative to each other, the inclination angle α of the flywheel 43 gradually decreases and becomes 0° by releasing the contact between the protrusion 43f and the stopper 41i. That is, the flywheel 43 quickly changes to a posture perpendicular to the rotating shaft 41e during operation, and the flywheel 43 can rotate relative to each other smoothly.

[0058] According to the retractor 1 of the present embodiment described above, when the flywheel 43 is not working, the protrusion 43f formed on the flywheel 43 is brought into contact with the stopper 41i formed on the locking gear 41 to tilt the flywheel 43. This can fill the gap of the flywheel 43 required when the flywheel 43 is working, thereby reducing the generation of vibration sound of the retractor 1 when it is not working.

[0059] Next, refer to Figure 6 A seat belt device according to an embodiment of the present invention will be described. Figure 6 FIG. 2 is a diagram showing the overall structure of a seat belt device according to an embodiment of the present invention. Figure 6In the figure, for convenience of explanation, components other than the seat belt device are shown by single-dot chain lines.

[0060] Figure 6 The seat belt device 100 of the present embodiment shown in the figure comprises: a webbing W for restraining an occupant; a retractor 1 for winding the webbing W; a guide anchor 101 provided on the vehicle body side for guiding the webbing W; a webbing anchor 102 for fixing the webbing W on the vehicle body side; a buckle 103 provided on the side of a seat S on which an occupant sits; and a tongue 104 provided on the webbing W. The retractor 1 has, for example, Figure 1 The structure shown.

[0061] The components other than the retractor 1 are briefly described below. The seat S includes, for example, a seat portion S1 on which an occupant sits, a backrest portion S2 located behind the occupant, and a headrest portion S3 for supporting the occupant's head. The retractor 1 is built into, for example, a B-pillar P of a vehicle body.

[0062] In general, the buckle 103 is often disposed on the side of the seat portion S1, and the webbing anchor 102 is often disposed on the lower surface of the seat portion S1. In addition, the guide anchor 101 is often disposed on the B-pillar P. One end of the webbing W is connected to the belt anchor 102, and the other end is connected to the retractor 1 via the guide anchor 101.

[0063] Therefore, when the tongue 104 is fitted in the buckle 103, the webbing W is pulled out from the retractor 1 while sliding in the insertion hole of the guide fixture 101. In addition, when the occupant wears the seat belt or releases the seat belt when getting off the vehicle, the spring unit 5 of the retractor 1 acts to wind the webbing W until a certain load is applied.

[0064] The seat belt device 100 is described as being applied to the seat S disposed at the front seat of the vehicle, but the seat belt device 100 may also be applied to the seat S disposed at the rear seat. The seat belt device 100 may also be applied to a seat belt device used in a vehicle other than a vehicle.

[0065] The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit and scope of the present invention.

[0066] Description of Reference Numerals

[0067] 1 retractor, 2 reel, 3 base frame, 4 locking mechanism, 5 spring unit, 6 retainer cover, 7 pretensioner, 31 engaging tooth, 41 locking gear, 41a disk portion, 41b outer peripheral wall, 41c center portion, 41d guide groove, 41e rotating shaft, 41f engaging claw, 41g engaging tooth, 41h guide portion, 41i stopper, 41j first engaging claw, 41k second engaging claw, 41m support portion, 41n protrusion, 41p tapered surface, 42 ratchet, 42a pin, 43 flywheel, 43a 43a first end portion, 43b second end portion, 43c insertion hole, 43d engaging hole, 43e convex portion, 43f projection, 43g curved surface, 44 hook spring, 44a support shaft, 45 locking base, 45a receiving portion, 45b shaft portion, 46 cap, 47 vehicle sensor, 47a mass body, 47b sensor rod, 47c sensor cover, 71 tube, 72 gas generator, 73 ring gear, 100 seat belt device, 101 guide fixer, 102 webbing fixer, 103 buckle, 104 tongue.

Claims

1. A retractor comprising: a reel for winding a webbing for restraining an occupant; a base frame for rotatably accommodating the reel; and a locking mechanism for limiting the rotation of the reel, wherein: The locking mechanism comprises: a locking gear, which is coaxially arranged with respect to the spool so as to be relatively rotatable; a ratchet, which is arranged to be engaged with the base frame; a flywheel, which is arranged on the locking gear and moves the ratchet by the relative rotation of the spool and the locking gear; and a hook spring, which applies force to the flywheel in a direction opposite to the relative rotation direction during operation. The flywheel has a protrusion disposed at the front end in the relative rotation direction. The lock gear has a stopper configured to contact with the protrusion to tilt the posture of the flywheel when not in operation and to release the contact with the protrusion when in operation.

2. The retractor according to claim 1, characterized in that: The stopper has a tapered surface at a portion that contacts the protrusion.

3. The retractor according to claim 1, characterized in that: The stopper includes a support portion provided upright from the lock gear and a protrusion portion formed to be contactable with an upper portion of the protrusion.

4. The retractor according to claim 1, characterized in that: The protrusion has a curved surface at a portion that contacts the stopper.

5. The retractor according to claim 1, characterized in that: The flywheel is configured to be supported at three points by the lock gear when not in operation.

6. The retractor according to claim 1, characterized in that: The locking gear comprises: a rotating shaft that supports the flywheel in a rotatable manner; a plurality of engaging claws that are arranged on the outer periphery of the rotating shaft; and a guide portion that is formed along the outer periphery of the root of the rotating shaft. The flywheel comprises: a through hole for inserting the rotating shaft; and an engaging hole for engaging the engaging claw. The flywheel is configured to be supported by the stopper, the engaging claw and the guide portion when not in operation.

7. The retractor according to claim 1, characterized in that: The hook spring is configured to urge the protrusion in a direction to contact the stopper when not in operation.

8. A seat belt device, characterized in that: A retractor according to any one of claims 1 to 7 is provided.

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