JP2020023271A - Webbing winding device - Google Patents

Abstract

To suppress operation of one clutch from being hindered by the other clutch.SOLUTION: The webbing winding device comprises a spool 14 that winds up a webbing to be attached to an occupant, and a first clutch 20 that is operated to transmit rotation force from the spool 14. Further, the webbing winding device comprises a second clutch 66, arranged adjacently to the first clutch 20, which is operated to transmit rotation force to the spool 14. Between the first clutch 20 and the second clutch 66 is provided a spacer 72 that suppresses interference of either one of the first clutch 20 and the second clutch 66 from affecting operation of the other of the first clutch 20 and the second clutch 66.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a webbing winding device.

  Patent Documents 1 and 2 below disclose a webbing take-up device in which a webbing mounted on an occupant is taken up on a spool by transmitting the rotational force of a motor to the spool. The webbing take-up device includes a clutch that transmits the rotational force of the motor to the spool. When the clutch operates, the rotational force of the motor is transmitted to the spool.

  By the way, in a configuration having a plurality of clutches for connecting and disconnecting the rotational force to and from the spool, it is important that the operation of one clutch is not hindered by the other clutch. It is.

JP 2010-208639 A JP 2014-125183 A

  The present invention has been made in view of the above-described circumstances, and has as its object to provide a webbing take-up device that can prevent the operation of one clutch from being hindered by the other clutch.

  The webbing take-up device according to the first aspect is configured to transmit a rotational force to the spool or to transmit a rotational force from the spool by operating the spool around which the webbing to be mounted on the occupant is taken up. A first clutch, a second clutch that is disposed adjacent to the first clutch and that is operated to transmit a rotational force to the spool, or to transmit a rotational force from the spool; A spacer provided between the first clutch and the second clutch, the spacer being provided between the first clutch and the second clutch to suppress an influence of the interference of one of the first clutch and the second clutch on the other operation of the first clutch and the second clutch. .

  The webbing take-up device according to a second aspect is the webbing take-up device according to the first aspect, wherein the spool is rotated in a take-up direction so that the webbing is taken up and the webbing is drawn out. Further comprising a force limiter mechanism that is rotated in the pull-out direction at a time and allows the spool to rotate in the pull-out direction with a force limiter load or more, and the first clutch is provided so as to be integrally rotatable with the spool and is operated. The second clutch is engaged with the first clutch via the spacer by being engaged with an engaged member provided on the outer side in the rotation radial direction so that the force limiter load can be switched. A ratchet that is rotatable integrally with the first clutch, and an engagement member provided on a radially outer side of the ratchet in the rotational direction. By Kigakarigo member is engaged with the ratchet, the rotational force of the take-up direction of the spool is transmitted to the ratchet.

  The webbing take-up device according to a third aspect is the webbing take-up device according to the second aspect, wherein the first clutch is displaced radially outward to be engaged with the engaged member. And a cover portion that covers the ratchet side of the clutch piece, and the spacer includes a first restricting portion that restricts movement of the ratchet toward the cover portion.

  The webbing take-up device according to a fourth aspect is the webbing take-up device according to the third aspect, wherein the spacer includes a second restricting portion that restricts movement of the ratchet to a side opposite to the cover portion. I have.

  The webbing take-up device according to a fifth aspect is the webbing take-up device according to any one of the first to fourth aspects, wherein the first clutch is configured such that the ratchet is engaged via the spacer. An engaging portion, the spacer includes an intervening portion interposed between the ratchet engaging portion and the ratchet, and in a state before the engaging member is engaged with the ratchet, the interposing portion A gap is formed between the ratchet engaging portion and the ratchet, and when the engaging member is engaged with the ratchet and the ratchet is rotated, the interposed portion is deformed, and The ratchet engaging portion comes into contact with the ratchet engaging portion.

  In the webbing take-up device according to the first aspect, the webbing mounted on the occupant is taken up on the spool. When the first clutch is operated, the rotational force is transmitted to the spool, or the rotational force from the spool is transmitted. Further, when the second clutch is operated, the rotational force is transmitted to the spool, or the rotational force is transmitted from the spool. Here, a spacer is provided between the first clutch and the second clutch. By having this spacer, the influence of the interference of one of the first clutch and the second clutch on the operation of the other of the first clutch and the second clutch is suppressed.

  The webbing take-up device according to the second aspect includes a force limiter mechanism. The force limiter mechanism allows the spool to rotate in the pull-out direction when the load is equal to or greater than the force limiter load. Then, when the first clutch is operated and the first clutch is engaged with the engaged member, the force limiter load can be switched. In addition, when the engaging member is engaged with the ratchet, the rotational force in the spool winding direction is transmitted to the ratchet. Thereby, the torque of the ratchet is transmitted to the spool via the first clutch, and the spool is rotated in the winding direction. Here, the ratchet is engaged with the first clutch via the spacer. Thereby, the influence on the operation of the first clutch due to the interference of the ratchet with the first clutch is suppressed.

  In the webbing take-up device according to the third aspect, when the clutch piece of the first clutch is displaced outward in the rotation radial direction and is engaged with the engaged member, the force limiter load can be switched. In addition, when the engaging member is engaged with the ratchet, the rotational force in the spool winding direction is transmitted to the ratchet. Thereby, the rotational force of the ratchet is transmitted to the spool via the ratchet engaging portion of the first clutch, and the spool is rotated in the winding direction. Here, the cover portion of the first clutch covers the ratchet side of the clutch piece. Then, the movement of the ratchet toward the cover portion of the first clutch is restricted by the first restricting portion of the spacer. This suppresses the influence of the ratchet on the operation of the first clutch due to interference with the cover portion and the clutch piece of the first clutch.

  In the webbing take-up device according to the fourth aspect, the movement of the ratchet to the side opposite to the cover portion is restricted by the second restriction portion of the spacer. This can prevent the ratchet from coming off the spacer.

  In the webbing take-up device according to the fifth aspect, before the engagement member is engaged with the ratchet, a gap is formed between the ratchet engagement portion and the ratchet by the intervening portion of the spacer. Thereby, generation of abnormal noise due to contact between the ratchet engaging portion and the ratchet is suppressed. Further, when the engagement member is engaged with the ratchet and the ratchet is rotated, the interposed portion of the spacer is deformed, and the ratchet and the ratchet engagement portion come into contact. Thereby, the rotational force of the ratchet can be directly transmitted to the ratchet engaging portion. As a result, it is not necessary to give the spacer a strength corresponding to the rotational force of the ratchet, and the weight of the spacer can be reduced.

It is an exploded perspective view showing the webbing take-up device of this embodiment in an exploded manner. FIG. 5 is an exploded perspective view showing the spool assembly in an exploded manner. FIG. 3 is an exploded perspective view showing a first clutch in an exploded manner. FIG. 4 is an exploded perspective view showing the switching mechanism in an exploded manner. It is an expanded sectional view which expands and shows the end part of the axial direction one side of a spool. (A) is a plan view showing the spacer, (B) is a side view showing the spacer, and (C) is a bottom view showing the spacer. It is a top view which shows the ratchet engaged with the ratchet engaging part of the guide part via the spacer. It is an expanded sectional view which expands and shows the end part of the axial direction one side of a spool, (A) has shown the state before a screw is attached, (B) has shown the state after a screw is attached. ing.

  A webbing take-up device according to an embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the webbing take-up device 10 of the present embodiment includes a frame 12, a spool 14, a webbing (not shown), a force limiter mechanism 16, a pretensioner mechanism 18, a first clutch 20, A switching mechanism 22, a pre-crash safety mechanism 24, and a winding attachment urging mechanism 26 are provided. Hereinafter, the terms “axial direction”, “radial direction”, and “circumferential direction” indicate the rotational axis direction, the rotational radial direction, and the rotational circumferential direction of the spool unless otherwise specified.

  The frame 12 includes a plate-shaped back plate 12A fixed to the vehicle body. Leg pieces 12B and 12C extend substantially at right angles from both ends in the width direction of the back plate 12A. A well-known lock mechanism and a pretensioner mechanism 18 are provided on the leg piece 12C side. On the leg piece 12B side, a switching mechanism 22, a pre-crash safety mechanism 24, and a winding attachment mechanism 26 are provided.

  The spool 14 is formed in a cylindrical shape having a through hole 14A (see FIG. 2) penetrating in the axial direction, and is disposed between the leg piece 12B and the leg piece 12C of the frame 12. The spool 14 is rotatably supported by the frame 12 via a main torsion shaft 28, a sub torsion shaft 30, and the like, which will be described later.

  The webbing is mounted on the occupant's body, and has a base end, which is one end in the longitudinal direction, locked to the spool 14. The spool 14 is rotationally urged in one winding direction (the direction of arrow C in FIG. 1 and the like) by the urging force of a mainspring spring (not shown) constituting a part of the winding attachment urging mechanism 26. . When the spool 14 is rotated in the winding direction, the webbing is wound on the spool 14 from the base end side. When the webbing is pulled out from the spool 14, the spool 14 is rotated in the pulling-out direction (the direction opposite to the arrow C in FIG. 1 and the like) which is the other rotation direction.

  As shown in FIG. 2, the force limiter mechanism 16 is configured to include a main torsion shaft 28, a sub-torsion shaft 30, and the like.

  The main torsion shaft 28 is arranged coaxially with the spool 14. A part of the main torsion shaft 28 is fixed to a lock gear (not shown) constituting a part of a lock mechanism so as to be integrally rotatable with the lock gear. The other part of the main torsion shaft 28 is fixed to the spool 14 so as to be integrally rotatable while being arranged on the inner peripheral portion of the spool 14. The portion of the main torsion shaft 28 between the portion fixed to the lock gear and the portion fixed to the spool 14 is torsionally deformed so that the kinetic energy of the occupant used for pulling the webbing is absorbed. It has become.

  The sub torsion shaft 30 is arranged coaxially with the main torsion shaft 28, and the base end side of the sub torsion shaft 30 from the center in the longitudinal direction is inserted into the through hole 14 A of the spool 14. The base end of the sub-torsion shaft 30 is fixed to the spool 14 so as to be able to rotate integrally with the spool 14. On the other hand, the distal end side of the sub-torsion shaft 30 from the longitudinal center portion protrudes from the spool 14 to the other axial side. Further, a spline-shaped engaging portion 30A is formed at the tip of the sub-torsion shaft 30. Then, the portion between the engagement portion 30A and the portion fixed to the spool 14 in the sub-torsion shaft 30 is torsionally deformed, so that the kinetic energy of the occupant used for pulling the webbing is absorbed. ing.

  As shown in FIG. 3, the first clutch 20 includes a sleeve 32, a clutch guide 34 as a guide, a clutch base 36, a clutch cover 38 as a cover, and a pair of clutch plates 40 as clutch pieces. , A screw 42 (see FIG. 2), and a pair of coil springs 44.

  The sleeve 32 is disposed coaxially with the sub-torsion shaft 30 (see FIG. 2). A through hole 32A penetrating in the axial direction is formed in the axial center of the sleeve 32, and the sub torsion shaft 30 is loosely inserted into the through hole 32A. A spline-shaped engaged portion 32B is formed on an inner peripheral portion of the sleeve 32, and an engaging portion 30A (see FIG. 2) of the sub-torsion shaft 30 is engaged with the engaged portion 32B. Have been. Thereby, the sleeve 32 is engaged with the sub-torsion shaft 30 so as to be integrally rotatable. The side of the sleeve 32 on the spool 14 side is a support portion 32C having a circular outer shape. The opposite side of the sleeve 32 from the spool 14 is a fitting portion as a ratchet engaging portion having a hexagonal outer shape. 32D.

  The clutch guide 34 is formed in an annular shape having a through hole 34A penetrating in the axial direction. The support portion 32C described above is inserted into the through hole 34A, whereby the clutch guide 34 is supported by the sleeve 32 so as to be relatively rotatable. At two positions in the circumferential direction of the clutch guide 34, a pair of coil spring housing portions 34B for housing the coil springs 44 are formed. In the clutch guide 34, a pair of clutch plate housing portions 34C for housing the pair of clutch plates 40 are formed adjacent to the respective coil spring housing portions 34B.

  The clutch base 36 is formed integrally with the sleeve 32. The clutch base 36 includes an annular portion 36A protruding radially outward from the sleeve 32. Further, the clutch base 36 includes a pair of locking portions 36B protruding radially outward from the annular portion 36A. These locking portions 36B are locked to a base end of an arm portion 40A of the clutch plate 40 described later.

  The clutch cover 38 is arranged coaxially with the sleeve 32, is arranged on the opposite side of the clutch guide 34 from the spool 14, and is arranged to face the clutch guide 34. The clutch cover 38 is formed in an annular shape having a through hole 38A penetrating in the axial direction, and a plurality of fitting claws 38B protruding radially inward are formed on an inner peripheral portion thereof. When the fitting portion 32D of the sleeve 32 is inserted into the through hole 38A and the plurality of fitting claws 38B are fitted with the fitting portion 32D, the clutch cover 38 is attached to the sleeve 32 and, consequently, the sub-torsion. The shaft 30 is integrally rotatably engaged with the shaft 30. In addition, the clutch cover 38 includes a spring locking portion 38C to which one end of the coil spring 44 is locked. The above-described clutch guide 34 is relatively rotatable with respect to the clutch cover 38 by the urging force of the coil spring 44 compressed between the spring locking portion 38C and the above-described clutch guide 34.

  The clutch plate 40 is disposed between the clutch cover 38 and the clutch guide 34. The clutch plate 40 has an arm portion 40A and an arc portion 40B formed at the tip of the arm portion 40A. At the base end of the arm portion 40A, a rotation shaft 40C that projects toward the clutch cover 38 and extends along the axial direction of the sub-torsion shaft 30 is formed. The clutch plate 40 is rotatably (tilted) supported by the clutch cover 38 by inserting the rotating shaft 40C into a hole 38D formed in the clutch cover 38. Further, flat teeth knurled teeth 40D are formed on the outer peripheral portion of the arc portion 40B (the tip portion of the clutch plate 40).

  As shown in FIG. 2, the screw 42 includes a screw portion 42A, a winding attachment urging mechanism engaging portion 42B disposed coaxially with the screw portion 42A, and the screw portion 42A and the winding attaching urging mechanism engaging portion 42B. And a pressing portion 42C having a larger diameter than that of the pressing portion 42C. The screw 42A is fixed to the sub-torsion shaft 30 by being screwed to the tip of the sub-torsion shaft 30 (see FIG. 2). The winding attachment urging mechanism 26 (see FIG. 1) is engaged with the winding attachment urging mechanism engaging portion 42B. Thereby, the urging force of the mainspring spring forming a part of the winding attachment urging mechanism 26 is transmitted to the spool 14 via the screw 42 and the sub-torsion shaft 30.

  As shown in FIG. 3, a hole 34D is formed in the clutch guide 34 described above. A trigger wire 46 (see FIG. 2) is inserted into the hole 34D. When the trigger wire 46 is inserted into the hole 34D and a part of the trigger wire 46 is in contact with the clutch cover 38, the relative rotation of the clutch guide 34 with respect to the spool 14 and the clutch cover 38 is restricted (the clutch Guide 34 is constrained to the inoperative position).

  Further, as described above, when the clutch guide 34 is restrained at the inoperative position, the coil spring 44 is compressed. As a result, the clutch guide 34 is urged to rotate to the operating position. Further, in this state, the clutch plate 40 is housed in the clutch plate housing portion 34C such that the knurl teeth 40D are housed inside the outer peripheral portion of the clutch guide 34.

  As shown in FIG. 4, the switching mechanism 22 includes a case 48 formed in a box shape, a base cartridge 52 attached to the case 48 and supplied with gas generated by the gas generator 50, And a piston 54 that operates by receiving the pressure of the gas generated by 50. The switching mechanism 22 includes a pawl 56 whose arrangement is switched by being pressed by the piston 54, and a lock ring 58 as an engaged member whose rotation is regulated by the pawl 56.

  The pawl 56 is formed in a substantially plate shape, and includes a shaft portion 56A, and an arm portion 56B and an engaging portion 56C formed to extend radially outward of the shaft portion 56A. . The shaft 56A is rotatably supported by the case 48. Further, in a state where the engaging portion 56C is engaged with a notch portion 58B of the lock ring 58 described later, the arm portion 56B is arranged so as to be close to the piston 54.

  The lock ring 58 is formed in a substantially annular shape and is rotatably supported by the case 48. The lock ring 58 is disposed coaxially with the first clutch 20 on the outer peripheral side of the first clutch 20 (see FIG. 2). Further, flat teeth knurl teeth 58A are formed on the inner peripheral portion of the lock ring 58. Further, a cutout portion 58B having a substantially triangular cross section is formed on the outer peripheral portion of the lock ring 58, and the cutout portion 58B is opened radially outward of the lock ring 58.

  As shown in FIG. 1, the pre-crash safety mechanism 24 includes a box-shaped case 60, a motor 62 attached to the case 60, and a motor 62 disposed in the case 60 and reducing the rotation of the motor 62. And a second clutch 66 (see FIG. 5) for transmitting the rotation of the motor 62 decelerated by the speed reducer 64 to the spool 14.

  As shown in FIG. 5, the second clutch 66 includes a ratchet 68 engaged with the sleeve 32 of the first clutch 20 via a spacer 72 described later so as to be integrally rotatable with the sleeve 32, and a radial direction of the ratchet 68. And a ratchet engaging piece 70 as an engaging member provided on the outside. In FIG. 5, hatching of the cross section of each member is omitted.

  As shown in FIGS. 2 and 5, the ratchet 68 is formed in a disk shape coaxial with the first clutch 20. A plurality of ratchet teeth 68A with which the ratchet engaging pieces 70 engage are formed on the outer peripheral portion of the ratchet 68. In the center of the ratchet 68, a fitting hole 68B having a hexagonal inner shape is formed. In the inner peripheral portion of the fitting hole 68B, three connection grooves 68C in which a connection portion 72D of the spacer 72 described later is disposed are formed along the axial direction. The three connection grooves 68C are arranged at regular intervals along the circumferential direction.

  As shown in FIGS. 1 and 5, the ratchet engagement piece 70 rotates around the ratchet 68 in the winding direction of the spool 14 when the rotation of the motor 62 is transmitted through the speed reducer 64. It is configured to be displaced to the ratchet 68 side. The rotational force of the motor 62 is transmitted to the ratchet 68 by engaging the ratchet engaging piece 70 displaced to the ratchet 68 with the ratchet teeth 68A of the ratchet 68. Further, the rotational force transmitted to the ratchet 68 is transmitted to the spool 14 via the sleeve 32 and the sub-torsion shaft 30, so that the spool 14 is rotated in the winding direction, and the webbing is wound on the spool 14. It has become.

  Next, the configuration of the spacer 72 will be described.

  As shown in FIGS. 5 and 6A to 6C, the spacer 72 is formed using a resin material. The spacer 72 includes a first restricting portion 72A formed in a substantially disk shape. A fitting hole 72B having a hexagonal inner shape and into which the fitting portion 32D of the sleeve 32 is inserted is formed at the center of the first restriction portion 72A.

  The spacer 72 includes six legs 72C protruding from the first restricting portion 72A toward the clutch base 36. The six legs 72C are arranged at equal intervals along the circumferential direction. In a state where the fitting portion 32D of the sleeve 32 is inserted into the fitting hole 72B of the first limiting portion 72A, the six legs 72C are arranged between the plurality of fitting claws 38B of the clutch cover 38, respectively. At the same time, the tips of the six legs 72C abut on the clutch base 36.

  Further, the spacer 72 includes three connection portions 72D as interposition portions that protrude from the first restriction portion 72A in a direction opposite to the direction in which the leg portions 72C protrude. These three connection portions 72D are arranged at equal intervals along the circumferential direction. The thickness of the three connection portions 72D in the radial direction is set to a thickness that allows elastic deformation in the radial direction when the rotational force of the motor 62 is transmitted to the ratchet 68.

  In addition, the spacer 72 includes second restriction portions 72E that protrude radially outward from ends of the three connection portions 72D opposite to the first restriction portions 72A. The axial dimension T from the second restricting portion 72E to the first restricting portion 72A is set to be slightly larger than the thickness dimension (dimension in the axial direction) of the ratchet 68. The end face of the second restriction part 72E on the side opposite to the first restriction part 72A is inclined radially inward toward the side opposite to the first restriction part 72A.

  Further, the spacer 72 includes three crushing ribs 72F that protrude from ends of the three connecting portions 72D opposite to the first limiting portion 72A toward the opposite side to the first limiting portion 72A. . The crushing rib 72F is formed in a conical shape that gradually narrows toward the opposite side to the first restricting portion 72A.

  Next, a procedure for engaging the ratchet 68 with the sleeve 32 of the first clutch 20 via the spacer 72 will be described.

  As shown in FIG. 5, first, the fitting portion 32D of the sleeve 32 is inserted into a fitting hole 72B formed in the center of the first restriction portion 72A of the spacer 72. Next, the fitting portion 32D of the sleeve 32 is inserted into the fitting hole 72B formed at the center of the ratchet 68. At this time, when the second restricting portion 72E of the spacer 72 is pressed against the inner peripheral surface of the fitting hole 72B of the ratchet 68, the connecting portion 72D of the spacer 72 is deformed radially inward. Thus, the portion of the spacer 72 including the second restriction portion 72E is reduced in diameter. As a result, the insertion of the ratchet 68 into the fitting hole 72B of the fitting portion 32D of the sleeve 32 is prevented from being hindered by the second restriction portion 72E of the spacer 72. When the insertion of the ratchet 68 of the fitting portion 32D of the sleeve 32 into the fitting hole 72B is completed, the connecting portion 72D of the spacer 72 is restored to the outside in the radial direction. Thereby, the portion of the spacer 72 including the second restriction portion 72E is enlarged. In this state, as shown in FIG. 7, the second limiting portion 72E of the spacer 72 and the edge of the fitting hole 72B of the ratchet 68 overlap in the axial direction. In a state before the ratchet engaging piece 70 is engaged with the ratchet 68, a gap 74 is formed between the fitting part 32D of the sleeve 32 and the ratchet 68 by the connecting part 72D of the spacer 72.

  Next, as shown in FIG. 5, the screw 42 </ b> A of the screw 42 is screwed to the tip of the sub-torsion shaft 30. As a result, the ratchet 68 and the spacer 72 are disposed between the holding portion 42C of the screw 42 and the clutch base 36. Through the above procedure, the ratchet 68 is engaged with the sleeve 32 of the first clutch 20 via the spacer 72.

  Here, in the present embodiment, as shown in FIGS. 8A and 8B, when the screw portion 42A of the screw 42 is screwed to the tip of the sub-torsion shaft 30, the crushing rib 72F of the spacer 72 is used. Is plastically deformed (crushed). This suppresses rattling of the spacer 72 between the pressing portion 42C of the screw 42 and the clutch base 36.

(Operation and effect of the present embodiment)
Next, the operation and effect of the present embodiment will be described.

  As shown in FIGS. 1 and 2, in the webbing take-up device 10 according to the present embodiment, the webbing is pulled out from the spool 14, so that the webbing is attached to the body of an occupant of the vehicle.

  Here, a control device (not shown) determines whether there is a high possibility that the vehicle will collide, based on signals from various sensors provided on the vehicle. Then, when the control device determines that there is a high possibility that the vehicle will collide, the control device rotates the motor 62. When the rotational force of the motor 62 is transmitted to the ratchet engaging piece 70 (see FIG. 5), the ratchet engaging piece 70 is displaced toward the ratchet 68 and engages with the ratchet teeth 68A of the ratchet 68. As a result, the torque of the motor 62 is transmitted to the ratchet 68, and the torque transmitted to the ratchet 68 is transmitted to the spool 14 via the sleeve 32 and the sub-torsion shaft 30. As a result, the spool 14 is rotated in the winding direction, and the webbing is wound on the spool 14. Thereby, the slack of the webbing can be removed before the collision of the vehicle. When the slack of the webbing is removed, the motor 62 is stopped, and the engagement between the ratchet engaging piece 70 and the ratchet teeth 68A of the ratchet 68 is released.

  When the webbing is mounted on the body of an occupant of the vehicle, for example, when the vehicle is rapidly decelerated and the lock mechanism is activated, the lock gear is prevented from rotating in the pulling-out direction. As a result, the rotation of the spool 14 connected to the lock gear via the main torsion shaft 28 in the pull-out direction is restricted, and the pull-out of the webbing from the spool 14 is restricted. Therefore, the body of the occupant trying to move forward of the vehicle is restrained by the webbing.

  In a state where the lock gear is prevented from rotating in the pulling-out direction, the occupant's body pulls the webbing with a larger force, and the turning force of the spool 14 in the pulling-out direction based on this pulling force causes the main torsion shaft 28 to twist. If the load (deformation resistance load) is exceeded, the force limiter mechanism 16 is operated, and the torsion (deformation) of the main torsion shaft 28 allows the spool 14 to rotate in the pull-out direction at a force greater than the force limiter load.

  Accordingly, the spool 14 is rotated in the pulling-out direction by the torsion of the main torsion shaft 28 and the webbing is drawn from the spool 14, so that the load (burden) on the occupant's chest due to the webbing is reduced. Further, the kinetic energy of the occupant used for pulling the webbing is absorbed by the twist of the main torsion shaft 28.

  On the other hand, as described above, when the spool 14 is rotated in the pull-out direction with respect to the lock gear, the trigger wire 46 is pulled. As a result, the distal end of the trigger wire 46 is pulled out from the hole 34D of the clutch guide 34 shown in FIG. 3, and the state of preventing the clutch guide 34 from rotating relative to the spool 14 and the clutch cover 38 is eliminated.

  As shown in FIGS. 3 and 4, when the clutch guide 34 is rotated from the non-operation position to the operation position by the urging force of the coil spring 44, the clutch plate 40 is rotated toward the lock ring 58. The knurl teeth 40D of the clutch plate 40 mesh with the knurl teeth 58A of the lock ring 58. As a result, the lock ring 58 attempts to rotate in the pull-out direction together with the rotation of the first clutch 20 in the pull-out direction (the rotational force of the spool 14 is transmitted to the lock ring 58 via the first clutch 20). .

  Further, the control device (not shown) determines whether or not the occupant's physique is equal to or greater than a predetermined reference value based on a signal from the physique detection means, and based on a signal from the collision detection means. It is determined whether or not has collided. When the control device determines that the occupant's physique is equal to or greater than the predetermined reference value, the gas generator 194 is not operated, and the engaging portion 56C of the pawl 56 engages with the notch 58B of the lock ring 58. I agree. Therefore, the rotation of the lock ring 58 in the pull-out direction is locked (prevented), so that the rotation of the first clutch 20 in the pull-out direction is blocked.

  Then, in a state where the rotation of the first clutch 20 in the pull-out direction of the sleeve 32 is prevented, the occupant's body pulls the webbing with a larger force, and the rotational force of the spool 14 in the pull-out direction based on this pulling force is the main force. If the torque exceeds the sum of the torsional load (deformation load) of the torsion shaft 28 and the torsional load (deformation load) of the sub torsion shaft 30, the force limiter load (main torsion) of the spool 14 is caused by the torsion (deformation) of both. (The sum of the torsional load of the shaft 28 and the torsional load of the sub-torsion shaft 30) or more in the drawing direction is allowed.

  Therefore, the load (load) on the occupant's chest due to the webbing is reduced by rotating the spool 14 in the pulling-out direction and pulling out the webbing from the spool 14 due to the twisting of the main torsion shaft 28 and the sub-torsion shaft 30. The kinetic energy of the occupant used for pulling the webbing is absorbed by the torsion of the main torsion shaft 28 and the sub torsion shaft 30.

  On the other hand, the control device determines that the occupant's physique is less than a predetermined reference value based on the signal from the physique detection means, and determines that the vehicle has collided based on the signal of the collision detection means. In this case, the gas generator 50 is operated under the control of the control device. Accordingly, the piston 54 presses the arm portion 56 </ b> B of the pawl 56 by moving the piston 54. As a result, the pawl 56 rotates about the shaft 56A, and the engagement between the engaging portion 56C of the pawl 56 and the notch 58B of the lock ring 58 is released. Accordingly, the rotation of the lock ring 58 in the pulling-out direction is allowed, and the first clutch 20 and the sub-torsion shaft 30 are allowed to rotate in the pulling-out direction together with the spool 14. Therefore, the torsion of the sub-torsion shaft 30 does not occur, and the torsion (deformation) of the main torsion shaft 28 causes the rotation of the spool 14 in the pull-out direction at a force limiter load (the torsional load of the main torsion shaft 28) or more. Permissible.

  That is, when the occupant's physique is equal to or larger than a predetermined reference value, the force limiter load is set to the sum of the torsional load of the main torsion shaft 28 and the torsional load of the sub-torsion shaft 30, and the force limiter load is reduced. The load value is increased. On the other hand, when the occupant's physique is less than the predetermined reference value and the collision of the vehicle is detected, the force limiter load is set to the torsional load of the main torsion shaft 28, and the load value of the force limiter load is reduced. Reduced load. Therefore, the occupant can be appropriately protected according to the physique.

  Here, as shown in FIG. 5, in the present embodiment, the ratchet 68 is engaged with the sleeve 32 of the first clutch 20 via the spacer 72. The clearance between the ratchet 68 and the clutch cover 38 of the first clutch 20 is secured by the leg 72C of the spacer 72, and the movement of the ratchet 68 toward the clutch cover 38 of the first clutch 20 is controlled by the spacer. 72 is restricted by the first restriction unit 72A. Thereby, the influence on the operation of the first clutch 20 due to the interference of the ratchet 68 with the clutch cover 38 and the clutch plate 40 (the rotating shaft 40C) of the first clutch 20 can be suppressed.

  In the present embodiment, the movement of the ratchet 68 to the side opposite to the clutch cover 38 is restricted by the second restricting portion 72E of the spacer 72. Thereby, it is possible to prevent the ratchet 68 from coming off the spacer 72 (the spacer 72 comes off from the ratchet 68).

  Further, in the present embodiment, as shown in FIGS. 5 and 7, before the ratchet engaging piece 70 is engaged with the ratchet 68, the fitting portion 32D of the sleeve 32 is connected by the connecting portion 72D of the spacer 72. A gap 74 is formed between the armature and the ratchet 68. Thereby, generation of abnormal noise due to contact between the fitting portion 32D of the sleeve 32 and the ratchet 68 can be suppressed.

  Further, when the rotational force of the motor 62 (see FIG. 1) is transmitted to the ratchet 68 via the ratchet engaging piece 70, when the ratchet 68 is rotated in the winding direction, the connecting portion 72D of the spacer 72 has a diameter. Deforms inward in the direction. Thereby, the ratchet 68 comes into contact with the fitting portion 32 </ b> D of the sleeve 32. Thereby, the rotational force of the ratchet 68 can be transmitted directly to the sleeve 32. As a result, it is not necessary to give the spacer 72 a strength corresponding to the rotational force of the ratchet 68, and the weight of the spacer 72 can be reduced.

  In the present embodiment, an example is described in which the ratchet 68 is prevented from contacting the clutch cover 38 and the clutch plate 40 of the first clutch 20 with the spacer 72, but the present invention is not limited to this. That is, the contact of the ratchet 68 with a portion of the first clutch 20 that may hinder the operation of the first clutch 20 may be suppressed by the spacer 72.

  Further, in the present embodiment, the spacer 72 is disposed between the first clutch 20 that transmits the rotational force of the spool 14 when activated and the second clutch 66 that transmits the rotational force to the spool 14 when activated. Has been described, but the present invention is not limited to this.

  For example, a spacer may be provided between a first clutch that transmits torque to the spool 14 when activated and a second clutch that transmits torque to the spool 14 when activated.

  Further, a spacer may be provided between the first clutch to which the rotational force of the spool 14 is transmitted when activated and the second clutch to which the rotational force of the spool 14 is transmitted when activated.

  Further, a spacer may be provided between the first clutch, which is activated to transmit the rotational force to the spool 14, and the second clutch, which is activated to transmit the rotational force to the spool 14.

  As described above, one embodiment of the present invention has been described, but the present invention is not limited to the above, and various modifications other than the above can be made without departing from the gist of the present invention. Of course.

DESCRIPTION OF SYMBOLS 10 ... Webbing take-up device, 14 ... Spool, 16 ... Force limiter mechanism, 20 ... 1st clutch, 32D ... Fitting part (ratchet engaging part), 38 ... Clutch cover (cover part), 40 ... Clutch plate (Clutch) 58) Lock ring (engaged member), 66 ... second clutch, 68 ... ratchet, 70 ... ratchet engaging piece (engaging member), 72 ... spacer, 72A ... first restricting portion, 72D ... connection Part (intervening part), 72E ... second restriction part

Claims (5)

A spool on which the webbing to be mounted on the occupant is wound up,
A first clutch that, when actuated, transmits torque to the spool or transmits torque from the spool;
A second clutch that is disposed adjacent to the first clutch and is operated to transmit torque to the spool or transmit torque from the spool;
A spacer that is provided between the first clutch and the second clutch and that suppresses the influence of the interference of one of the first clutch and the second clutch on the operation of the other of the first clutch and the second clutch; When,
Webbing take-up device provided with. The webbing is wound up by being rotated in the winding direction, and the webbing is rotated in the withdrawing direction by being pulled out,
Further provided with a force limiter mechanism that allows rotation of the spool in a pull-out direction at or above a force limiter load,
The first clutch is provided so as to be integrally rotatable with the spool, is operated and is engaged with an engaged member provided on the outer side in the rotation radial direction, so that the force limiter load can be switched,
The second clutch is configured to be engaged with the first clutch via the spacer, and the ratchet is configured to be integrally rotatable with the first clutch, and an engagement member provided on a rotation radial outside of the ratchet. The webbing take-up device according to claim 1, wherein the engagement member is engaged with the ratchet, whereby a rotational force in a take-up direction of the spool is transmitted to the ratchet. The first clutch is configured to include a clutch piece that is displaced radially outward to be engaged with the engaged member, and a cover that covers the ratchet side of the clutch piece,
The webbing retractor according to claim 2, wherein the spacer includes a first restricting portion that restricts movement of the ratchet toward the cover portion.   The webbing take-up device according to claim 3, wherein the spacer includes a second restricting portion that restricts movement of the ratchet to a side opposite to the cover portion. The first clutch includes a ratchet engaging portion with which the ratchet is engaged via the spacer.
The spacer includes an interposition portion interposed between the ratchet engagement portion and the ratchet,
In a state before the engagement member is engaged with the ratchet, a gap is formed between the ratchet engagement portion and the ratchet by the interposition portion,
5. The ratchet according to claim 2, wherein when the engaging member is engaged with the ratchet and the ratchet is rotated, the interposed portion is deformed, and the ratchet and the ratchet engaging portion come into contact with each other. 6. The webbing winding device according to claim 1.