Seat belt retractor

Patent metadata

Field	Value
Publication number	US-2023249643-A1
Application number	US-202318163069-A
Country	US
Kind code	A1
Filing date	Feb 1, 2023
Priority date	Feb 4, 2022
Publication date	Aug 10, 2023
Grant date	—

Abstract

A seat belt retractor includes a vehicle acceleration sensor. The vehicle acceleration sensor includes a sensor holder including a placement surface and an attachment member to which the sensor holder is coupled. The attachment member is attached to the housing in a state in which the sensor holder is in either a first posture or a second posture. The sensor holder is configured to be coupled to the attachment member at any one of a plurality of angular positions. The plurality of angular positions are positions of the sensor holder in a case where the sensor holder rotates around a rotation axis. A plurality of sensor attachment angles corresponding to the plurality of angular positions are different between the first posture and the second posture. The plurality of sensor attachment angles are angles, with respect to the housing, of the center line of the placement surface.

First claim

What is claimed is:

1 . A seat belt retractor comprising:
a vehicle acceleration sensor configured to be in a detection state in a case where an acceleration of a vehicle is equal to or greater than a predetermined value; and a winding drum accommodated, in a housing, to be rotatable in a pull-out direction and a winding direction of a webbing, the winding drum being configured not to rotate in the pull-out direction in a case where the vehicle acceleration sensor is in the detection state, wherein the vehicle acceleration sensor includes:
an inertial mass body having a spherical shape;
a sensor holder including a placement surface having a mortar shape and a cross-sectional shape symmetrical with respect to a center line of the placement surface, the inertial mass body being placed on the placement surface;
a sensor lever swingably supported by the sensor holder, the sensor lever being pushed up by the inertial mass body rolling on the placement surface in a case where the acceleration of the vehicle is equal to or greater than the predetermined value; and
an attachment member to which the sensor holder is coupled and which is attached to the housing,
the attachment member is attached to the housing in a state in which the sensor holder is in either a first posture or a second posture inverted about the center line of the placement surface with respect to the first posture, the sensor holder is configured to be coupled to the attachment member at any one of a plurality of angular positions in each of the first posture and the second posture, the plurality of angular positions being positions of the sensor holder in a case where the sensor holder rotates around a rotation axis extending in a direction orthogonal to the center line of the placement surface, and a plurality of sensor attachment angles corresponding to the plurality of angular positions are different between the first posture and the second posture, the plurality of sensor attachment angles being angles, with respect to the housing, of the center line of the placement surface.

2 . The seat belt retractor according to claim 1 ,
wherein the sensor holder is provided with an outward engagement portion including at least one outward protrusion that is pointed radially outward about the rotation axis, the attachment member is provided with an inward engagement portion including at least one inward protrusion that is pointed radially inward about the rotation axis, the inward engagement portion being configured to engage with the outward engagement portion, one or both of the at least one outward protrusion and the at least one inward protrusion are provided in plural and arranged in a circumferential direction around the rotation axis, and the sensor holder is configured to be coupled to the attachment member at any one of the plurality of angular positions in accordance with a change of an engaged state between the outward engagement portion and the inward engagement portion.

3 . The seat belt retractor according to claim 2 ,
wherein the sensor holder is configured to be in either the first posture or the second posture by inverting an orientation of the sensor holder in a case where the sensor holder is coupled to the attachment member, and the outward engagement portion and the inward engagement portion are configured to be engaged with each other in both the first posture and the second posture.

4 . The seat belt retractor according to claim 3 ,
wherein the number of portions of the inward engagement portion is one, the outward engagement portion includes:
a first outward engagement portion configured to be engaged with the inward engagement portion, in the first posture; and
a second outward engagement portion configured to be engaged with the inward engagement portion, in the second posture, and
the first outward engagement portion and the second outward engagement portion are different in a position of the at least one outward protrusion when viewed from an extending direction of the rotation axis.

5 . The seat belt retractor according to claim 3 ,
wherein the number of portions of the outward engagement portion is one, the inward engagement portion includes:
a first inward engagement portion configured to be engaged with the outward engagement portion, in the first posture; and
a second inward engagement portion configured to be engaged with the outward engagement portion, in the second posture, and
the first inward engagement portion and the second inward engagement portion are different in a position of the at least one inward protrusion when viewed from an extending direction of the rotation axis.

6 . The seat belt retractor according to claim 3 ,
wherein the inward engagement portion includes a first inward engagement portion and a second inward engagement portion, the outward engagement portion includes a first outward engagement portion and a second outward engagement portion, the first outward engagement portion is configured:
to be engaged with the first inward engagement portion, in the first posture;
not to be engaged with the second inward engagement portion, in the first posture; and
not to be engaged with the first inward engagement portion and the second inward engagement portion, in the second posture, and
the second outward engagement portion is configured:
not to be engaged with the first inward engagement portion and the second inward engagement portion, in the first posture;
to be engaged with the second inward engagement portion, in the second posture; and
not to be engaged with the first inward engagement portion, in the second posture.

7 . The seat belt retractor according to claim 2 ,
wherein, by reversing an orientation of the attachment member with respect to the housing, the attachment member is configured to be attached to the housing either in a state in which the sensor holder is in the first posture or in a state in which the sensor holder is in the second posture.

8 . The seat belt retractor according to claim 2 ,
wherein the outward engagement portion is asymmetric with respect to a plane including the rotation axis and the center line of the placement surface.

9 . The seat belt retractor according to claim 1 ,
wherein the sensor holder includes:
a first support portion configured to swingably support the sensor lever in the first posture; and
a second support portion configured to swingably support the sensor lever in the second posture, the second support portion being located on a side opposite to the first support portion with respect to the center line of the placement surface.

10 . The seat belt retractor according to claim 9 ,
wherein a shape of the sensor holder is asymmetric with respect to a plane that is perpendicular to a direction in which the first support portion and the second support portion are separated from each other, and that includes the center line of the placement surface.

11 . The seat belt retractor according to claim 10 ,
wherein the first support portion of the sensor holder and the second support portion of the sensor holder have different heights, in a direction along the center line of the placement surface, from the placement surface.

Assignees

• Ashimori Ind Co Ltd

Inventors

• Yokoyama Taro
• Suminaka Satoshi
• Ijiri Takayoshi
• Kurauchi Noriko

Classifications

• B60R22/40 Primary

  responsive only to vehicle movement · CPC title

• B60R2022/401

  with adjustable sensor · CPC title

• B60R22/405

  responsive to belt movement and vehicle movement · CPC title