Webbing retractor

• US 6,598,822 B2
• Filed: 10/24/2001
• Issued: 07/29/2003
• Est. Priority Date: 10/26/2000
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Tokai RIKA Denki Seisakusho
• Original Assignee: Kabushiki Kaisha Tokai RIKA Denki Seisakusho
• Inventors: Mori, Shinji, Kitazawa, Yasuho, Nagata, Tomonori
• Primary Examiner(s): RIVERA, WILLIAM ARAUZ
• Application Number:
  US09/983,553
• Publication Number:
  US 20020050542A1
• Time in Patent Office: 643 Days
• Field of Search: 242/379.1, 242/384, 242/396.1, 242/396.4, 280/805, 280/806, 280/807, 297/472, 297/475
• US Class Current: 242/379.1
• CPC Class Codes: B60R 22/341 comprising energy-absorbing means
• CPC Class Codes: B60R 22/40 responsive only to vehicle movement

Abstract

A webbing retractor is disclosed. One end portion of a plate is fixed to a hollow cylindrical portion of a spool. An intermediate portion of the plate is entrained around an engaging pin and the like of a gear which can rotate relatively to the spool. A pawl provided at the gear abuts the plate, and is held at a position of non-engagement with stopper teeth against urging force of a coil spring. When the spool and the gear rotate relatively, the plate, whose widthwise dimension decreases toward a final end portion thereof, is taken-up onto the hollow cylindrical portion while being rubbed by the engaging pin and the like. A force limiter load in an energy absorbing process is decreased. The pawl, whose engagement with the plate is released, meshes with the stopper teeth such that rotation of the spool is impeded.

Claims

1. A webbing retractor comprising:

a spool on which a webbing is taken-up and from which a webbing is pulled-out;

a rotating member provided so as to be coaxial with the spool and so as to be rotatable relative to the spool, the rotating member usually rotating integrally with the spool, and in predetermined cases, rotation of the rotating member in a webbing pull-out direction is impeded;

an elongated member whose first end portion is fixed to one of the spool and the rotating member, and whose intermediate portion is engaged with another of the spool and the rotating member, and when rotation of the rotating member in the webbing pull-out direction is impeded, accompanying relative rotation of the spool and the rotating member, the elongated member is rubbed at an engaged region thereof; and

a stopper device provided at the spool or the rotating member with which the intermediate portion is engaged so as to abut the intermediate portion of the elongated member, and when, accompanying relative rotation of the spool and the rotating member, a state of abutment of the stopper device with the elongated member is cancelled, the stopper device impedes relative rotation, in the webbing pull-out direction, of the spool with respect to the rotating member.

2. A webbing retractor according to claim 1, wherein the elongated member is disposed between an outer peripheral portion of the one of the spool and the rotating member and an inner peripheral portion of the spool or the rotating member with which the intermediate portion is engaged, the outer peripheral portion and the inner peripheral portion opposing one another, and accompanying relative rotation of the spool and the rotating member, the elongated member is taken-up onto the outer peripheral portion of the one of the spool and the rotating member.

3. A webbing retractor according to claim 1, wherein, at the elongated member, a sectional area of the intermediate portion which is rubbed at least at an engaged region of the intermediate portion decreases gradually toward second end portion of the elongated member.

4. A webbing retractor according to claim 3, further comprising an urging device receiving portion provided on the rotating member, wherein the stopper device includes a pawl and an urging device, the pawl whose end portion is rotatably supported on a surface of the rotating member, the urging device provided between the pawl and the urging device receiving portion.

5. A webbing retractor according to claim 1, further comprising:

a lock device provided coaxially with the rotating member;

a lock base provided at the first end side of the spool so as to be coaxial with the spool and so as to be able to rotate relatively with respect to the spool, and when one of a rapid deceleration of a vehicle and rapid pulling-out of a webbing is sensed, rotation of the lock base in the webbing pull-out direction is impeded by the locking device; and

a torsion bar provided within the spool and coaxially with the spool, one end portion of the torsion bar being connected to the spool and another end portion of the torsion bar being connected to the lock base, the torsion bar usually being made to rotate integrally with the spool and the lock base, and when rotation of the lock base in the webbing pull-out direction is impeded, the torsion bar, while twisting due to tensile force of the webbing, rotates the spool in the webbing pull-out direction relatively to the lock base.

6. A webbing retractor according to claim 5, wherein the lock base also functions as the rotating member.

7. A webbing retractor according to claim 6, wherein the spool includes substantially arc guiding projections coaxial with the spool, and the stopper device includes a pawl and an urging device, the pawl whose end portion is rotatably supported on a surface of the gear, the urging device provided between the pawl and the urging device receiving portion.

8. A webbing retractor comprising:

a spool on which a webbing is taken-up and from which a webbing is pulled-out;

a gear provided so as to be coaxial with the spool and so as to be rotatable relative to the spool, the gear usually rotating integrally with the spool, and in predetermined cases, rotation of the gear in a webbing pull-out direction is impeded;

an elongated member whose first end portion is fixed to the spool, and whose intermediate portion is engaged with the gear, and when rotation of the gear in the webbing pull-out direction is impeded, accompanying relative rotation of the spool and the gear, the elongated member is rubbed at an engaged region thereof; and

a stopper device provided at the gear so as to abut the intermediate portion of the elongated member, and when, accompanying relative rotation of the spool and the gear, a state of abutment of the stopper device with the elongated member is cancelled, the stopper device impedes relative rotation, in the webbing pull-out direction, of the spool with respect to the gear.

9. A webbing retractor according to claim 8, wherein the elongated member is disposed between an outer peripheral portion of the spool and an inner peripheral portion of the gear, the outer peripheral portion and the inner peripheral portion opposing one another, and accompanying relative rotation of the spool and the gear, the elongated member is taken-up onto the outer peripheral portion of the spool.

10. A webbing retractor according to claim 8, wherein, at the elongated member, a sectional area of the intermediate portion which is rubbed at least at an engaged region of the intermediate portion decreases gradually toward second end portion of the elongated member.

11. A webbing retractor according to claim 10, further comprising an urging device receiving portion provided on the gear, wherein the stopper device includes a pawl and an urging device, the pawl whose end portion is rotatably supported on a surface of the gear, the urging device provided between the pawl and the urging device receiving portion.

12. A webbing retractor according to claim 11, wherein the urging device is a coil spring.

13. A webbing retractor according to claim 8, further comprising:

a lock device provided coaxially with the gear;

a lock base provided at the first end side of the spool so as to be coaxial with the spool and so as to be able to rotate relatively with respect to the spool, and when one of a rapid deceleration of a vehicle and rapid pulling-out of a webbing is sensed, rotation of the lock base in the webbing pull-out direction is impeded by the locking device; and

a torsion bar provided within the spool and coaxially with the spool, one end portion of the torsion bar being connected to the spool and another end portion of the torsion bar being connected to the lock base, the torsion bar usually being made to rotate integrally with the spool and the lock base, and when rotation of the lock base in the webbing pull-out direction is impeded, the torsion bar, while twisting due to tensile force of the webbing, rotates the spool in the webbing pull-out direction relatively to the lock base.

14. A webbing retractor according to claim 11, further comprising a frame including a pair of leg plates fixed to a vehicle body, wherein the lock device includes a lock plate held at a portion of the lock base, a ratchet formed at one of the leg plates of the frame, and a V gear provided coaxial with and adjacent to the lock base, the V gear having a larger diameter than the lock base.

15. A webbing retractor comprising:

a spool on which a webbing is taken-up and from which a webbing is pulled-out;

a lock base provided so as to be coaxial with the spool and so as to be rotatable relative to the spool, the lock base usually rotating integrally with the spool, and in predetermined cases, rotation of the lock base in a webbing pull-out direction is impeded;

an elongated member whose first end portion is fixed to the lock base, and whose intermediate portion is engaged with the lock base, and when rotation of the lock base in the webbing pull-out direction is impeded, accompanying relative rotation of the spool and the lock base, the elongated member is rubbed at an engaged region thereof; and

a stopper device provided at the lock base so as to abut the intermediate portion of the elongated member, and when, accompanying relative rotation of the spool and the lock base, a state of abutment of the stopper device with the elongated member is cancelled, the stopper device impedes relative rotation, in the webbing pull-out direction, of the spool with respect to the lock base.

16. A webbing retractor according to claim 15, wherein the elongated member is disposed between an outer peripheral portion of the lock base and an inner peripheral portion of the spool, the outer peripheral portion and the inner peripheral portion opposing one another, and accompanying relative rotation of the spool and the lock base, the elongated member is taken-up onto the outer peripheral portion of the lock base.

17. A webbing retractor according to claim 16, wherein the spool includes substantially arc guiding projections coaxial with the spool, and the stopper device includes a pawl and an urging device, the pawl whose end portion is rotatably supported on a surface of the gear, the urging device provided between the pawl and the urging device receiving portion.

18. A webbing retractor according to claim 17, wherein the urging device is a coil spring.

19. A webbing retractor according to claim 15, wherein, at the elongated member, a sectional area of the intermediate portion which is rubbed at least at an engaged region of the intermediate portion decreases gradually toward second end portion of the elongated member.

20. A webbing retractor according to claim 15, further comprising:

a lock device provided coaxially with the lock base wherein, when one of a rapid deceleration of a vehicle and rapid pulling-out of a webbing is sensed, rotation of the lock base in the webbing pull-out direction is impeded by the locking device; and

a torsion bar provided within the spool and coaxially with the spool, one end portion of the torsion bar being connected to the spool and another end portion of the torsion bar being connected to the lock base, the torsion bar usually being made to rotate integrally with the spool and the lock base, and when rotation of the lock base in the webbing pull-out direction is impeded, the torsion bar, while twisting due to tensile force of the webbing, rotates the spool in the webbing pull-out direction relatively to the lock base.