Seatbelt device

Patent metadata

Field	Value
Publication number	US-11148635-B2
Application number	US-201916966509-A
Country	US
Kind code	B2
Filing date	Jan 23, 2019
Priority date	Feb 2, 2018
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

An inclination controlling mechanism of a seatbelt device is provided with: a pulley that converts an advancing/retracting movement of a cable of the cable advancing/retracting mechanism; a drive gear mounted around a pivot shaft of the pulley and synchronized with rotation of the pulley; and a driven gear mounted around a pivot shaft of a sensor housing so as to move in conjunction with a rotation of the sensor housing. The drive gear and driven gear engage with each other in a condition where a rotational track surface of the drive gear and rotational track surface of the driven gear intersect at a predetermined angle. As a result, an inertial body supporting surface serving as a sensor reference plane can be accurately maintained horizontally even at an arbitrary seatback recline angle, and thus the accuracy of the acceleration sensor can be improved.

First claim

The invention claimed is:

1. A seatbelt device, comprising:
a seatbelt retractor mounted on a seat back of a reclining seat and that winds up a seatbelt when necessary; and
a cable advancing/retracting mechanism disposed on a coupling part of the seat back and a seat cushion of the reclining seat, and having a cable for detecting a recline angle when the seat back reclines in a front-back direction of the seat and transmitting the recline angle to the seatbelt retractor, the cable advancing or retracting in a length direction of the cable at a distance corresponding to the recline angle of the seat back; wherein
the seatbelt retractor comprises:
a retractor frame secured to the seat back, inclining in a left-right direction of the seat with regard to a straight line extending in a vertical direction through a center of the seat back in the left-right direction;
a spindle supported by the retractor frame for winding the seatbelt;
an acceleration sensor mounted on the retractor frame and that detects acceleration in the front-back direction of the seat;
a locking mechanism that locks a pull-out operation of the seatbelt based on the acceleration in the front-back direction of the seat detected by the acceleration sensor; and
a inclination controlling mechanism that keeps a sensor reference plane of the acceleration sensor horizontal;
the acceleration sensor comprises:
a sensor cover secured to the retractor frame;
an inertial body that moves in the front-back direction of the seat when an acceleration that is greater than a predetermined value acts in the front-back direction of the seat;
a sensor housing having a pivot shaft along the left-right direction of the seat, that is maintained in the sensor cover, and having an inertial body supporting surface where the inertial body is mounted; and
an actuating member that actuates the locking mechanism to a locking side in conjunction with the inertial body moving in the front-back direction of the seat; the inclination controlling mechanism comprises:
a pulley that converts the advancing/retracting movement of the cable advancing/retracting mechanism into a rotational motion;
a drive gear provided around a rotation shaft of the pulley and synchronized with rotation of the pulley; and
a driven gear mounted around the pivot shaft of the sensor housing so as to move in conjunction with the rotation of the sensor housing; wherein
the rotation shaft of the pulley and pivot shaft of the sensor housing intersect at a predetermined angle such that the pivot shaft of the sensor housing is provided in a horizontal direction with regard to the left-right direction of the seat;
the inertial body supporting surface of the sensor housing is maintained in a horizontal condition by pivoting the sensor housing in the front-back direction even if the seat back is reclined in the front-back direction of the seat; and
the drive gear and driven gear engage with each other in a condition where a rotational track surface of the drive gear and rotational track surface of the driven gear intersect at the predetermined angle.

2. The seat belt device according to claim 1 , wherein a cam member that advances/retracts the cable by the distance based on the recline angle of the seat back by winding or pulling the cable based on rotation is provided in the cable advancing/retracting mechanism,
cable winding parts of the pulley and cam member are circular or arc-shaped, and
when the winding radius of the cable of the cable winding part of the cam member is α times the cable winding radius of the cable winding part of the pulley, the gear ratio between the drive gear and driven gear is α.

3. The seatbelt device according to claim 1 , wherein the driven gear is formed in a substantially fan-like shape.

4. The seatbelt device according to claim 1 , wherein the driven gear is fitted and secured in a non-circular portion provided on a boss part formed above the pivot shaft of the sensor housing, and the pulley extends along the rotation shaft, and has a shaft part where the driven gear is mounted such that the drive gear engages at a position in the axial direction of the driven gear.

5. The seatbelt device according to claim 1 , wherein the sensor cover is separately provided from the inclination controlling mechanism,
the pivot shaft of the sensor housing is mounted in the horizontal direction with regard to the left-right direction of the seat, and
the sensor cover is formed such that the rotation shaft of the pulley and pivot shaft of the sensor housing intersect at the predetermined angle.

6. The seatbelt device according to claim 1 , wherein the driven gear is mounted around the pivot shaft of the sensor housing on the pulley side with regard to the inertial body supporting surface.

7. The seatbelt device according to claim 1 , wherein the driven gear is mounted around the pivot shaft of the sensor housing on a side separated from the pulley with regard to the inertial body supporting surface.

8. A seatbelt device, comprising: a seatbelt retractor mounted on a seat back of a reclining seat and that winds up a seatbelt when necessary; and a cable advancing/retracting mechanism disposed on a coupling part of the seat back and a seat cushion of the reclining seat, and having a cable for detecting a recline angle when the seat back reclines in the front-back direction of the seat and transmitting the recline angle to the seatbelt retractor, the cable advancing or retracting in a length direction of the cable at a distance corresponding to the recline angle of the seat back; wherein the seatbelt retractor comprises: a retractor frame secured to the seat back, inclining in a left-right direction of the seat with regard to a straight line extending in a vertical direction through a center of the seat back in the left-right direction; a spindle supported by the retractor frame for winding the seatbelt; an acceleration sensor mounted on the retractor frame and that detects acceleration in the front-back direction of the seat; a locking mechanism that locks a pull-out operation of the seatbelt based on the acceleration in the front-back direction of the seat detected by the acceleration sensor; and a inclination controlling mechanism that keeps a sensor reference plane of the acceleration sensor horizontal; the acceleration sensor comprises: a sensor cover secured to the retractor frame; an inertial body that moves in the front-back direction of the seat when an acceleration that is greater than a predetermined value acts in the front-back direction of the seat; a sensor housing having a pivot shaft along the left-right direction of the seat, that is maintained in the sensor cover, and having an inertial body supporting surface where the inertial body is mounted; and an actuating member that actuates the locking mechanism to a locking side in conjunction with the inertial body moving in the front-back direction of the seat; the inclination controlling mechanism comprises: a pulley that converts the advancing/retracting movement of the cable advancing/retracting mechanism into a rotational motion; a drive gear synchronized with rotation of the pulley; and a driven gear mounted around the pivot shaft of the sensor housing so as to move in conjunction with the rotation of the sensor housing; wherein the rotation shaft of the pulley and pivot shaft of the sensor housing intersect at a predetermined angle such that the pivot shaft of the sensor housing is provided in a horizontal direction with regard to the left-right direction of the seat; the inertial body supporting surface of the sensor housing is maintained in a horizontal condition by pivoting the sensor housing in the front-back direction even if the seat back is reclined in the front-

Assignees

• Autoliv Dev

Inventors

• Ito Katsuhiro
• Matsuki Masuo
• Hibata Ganta

Classifications

• B60R22/40 Primary

  responsive only to vehicle movement · CPC title

• B60R22/26

  secured to the seat · CPC title

• B60R2022/401

  with adjustable sensor · CPC title

• B60Y2400/70

  Gearings · CPC title

• B60R22/48 Primary

  Control systems, alarms, or interlock systems, for the correct application of the belt or harness · CPC title