Seat belt retractor

Patent metadata

Field	Value
Publication number	US-10196034-B2
Application number	US-201515519601-A
Country	US
Kind code	B2
Filing date	Aug 31, 2015
Priority date	Oct 22, 2014
Publication date	Feb 5, 2019
Grant date	Feb 5, 2019

Abstract

A switching mechanism (100) in a force limiter mechanism of a seat belt retractor including: a locking mechanism including a locking element (68) that locks a torque tube (64) with respect to a spindle (61) so that the torque tube (64) rotates together with the spindle (61) and a spindle ring (70); a switch ring (120) rotatable to unlock the locking mechanism; and a switch housing (101) that stores the switch ring (120), a switch piston (115) adapted to activate the switch ring (120). A switching gas generator (116) generates gas for pushing out the switch piston (115) upon activation of the switching mechanism. The switch housing (101) of the switching mechanism (100) has a protrusion (110) that protrudes in an incoming direction of an operated part (122) at an abutment part hit by the switch ring (120) rotated by the switch piston (115) to control movement of the switch ring.

First claim

The invention claimed is:

1. A seatbelt retractor, comprising:
a retractor frame;
a spindle rotatably supported by the retractor frame and capable of winding up a seatbelt therearound;
a torsion bar provided in the spindle and having a first end coupled to the spindle and a plurality of shaft parts having different torsional torque characteristics;
an emergency locking mechanism capable of locking rotation of the spindle by locking a second end of the torsion bar;
a torque tube coupled to the torsion bar between the plurality of shaft parts and provided in the spindle; and
a switching mechanism implementing switching between a first state in which the torque tube rotates together with the spindle and a second state in which the torque tube rotates relatively to the spindle,
the switching mechanism further comprising:
a locking mechanism locking the torque tube with respect to the spindle so that the torque tube rotates together with the spindle;
a switching member capable of rotating to unlock the locking mechanism;
a housing storing the switching member, a driving member adapted to activate the switching member, and a gas generator that generates gas for pushing out the driving member upon activation of the switching mechanism,
the housing of the switching mechanism having a protrusion that protrudes in an incoming direction of the switching member at an abutment part, the switching member hitting the abutment part when the switching member is rotated by the driving member.

2. The seatbelt retractor according to claim 1 , further comprising the protrusion deforms when the switching member hits the protrusion.

3. The seatbelt retractor according to claim 1 , wherein the locking mechanism comprises:
a locking member attached on a spindle side in a through hole provided radially through the spindle and rotatable between a locking position associated with the first state in which the torque tube is locked with respect to the spindle so that the torque tube rotates together with the spindle and an unlocking position associated with the second state in which the torque tube is unlocked from the spindle so that the torque tube rotates relatively to the spindle, and
a restriction ring radially abutting against the locking member to restrict the locking member in the locking position,
the switching member is a switch ring having an operated part that is movable axially from a first position in which the restriction ring abuts against the locking member, to a second position apart from the locking member and that is allowed to protrude radially and hit the protrusion at the abutment part, and
the protrusion extends axially to protrude in the incoming direction of the switching member.

4. The seatbelt retractor according to claim 3 , wherein the housing of the switching mechanism comprises a plurality of ramp surfaces inclined in a moving direction of the switch ring at a sliding surface on which the switch ring slides, and
the switch ring moves axially by sliding along the plurality of ramp surfaces while rotating in a circumferential direction by activation of the driving member.

5. The seatbelt retractor according to claim 3 , further comprising the protrusion is formed into a substantially triangular shape and collapses and deforms as the operating part of the switch ring when moving axially hits the protrusion wherein the switch ring is restricted from shifting in the axial direction.

6. The seatbelt retractor according to claim 1 , further comprising the switching member after hitting the abutment part when the switching member is rotated by the driving member is restricted from further movement in the circumferential direction.

7. The seatbelt retractor according to claim 1 , further comprising the protrusion is formed integrally with the housing.

Assignees

• Autoliv Dev

Inventors

• Sasahara Takaomi

Classifications

• B60R22/34

  Belt retractors, e.g. reels (anchoring devices {, e.g. guide loops} , with means to tension the belt in an emergency B60R22/195) · CPC title

• B60R22/4676

  comprising energy-absorbing means operating between belt reel and retractor frame · CPC title

• B60R22/3413 Primary

  operating between belt reel and retractor frame (B60R22/4676 takes precedence) · CPC title

• B60R22/28 Primary

  incorporating energy-absorbing devices {(belt anchors provided with energy-absorbing means for protecting the occupants in case of physical contact therewith B60R21/055; belt retractors comprising energy-absorbing means B60R22/341, B60R22/4676)} · CPC title

• B60R2022/288

  with means to adjust or regulate the amount of energy to be absorbed · CPC title