Seat belt device

• US 20060087108A1
• Filed: 01/20/2004
• Published: 04/27/2006
• Est. Priority Date: 01/23/2003
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Autoliv AB (Autoliv Incorporated)
• Inventors: Midorikawa, Yukinori
• Granted Patent: US 7,419,026 B2
• Time in Patent Office: Days
• US Class Current: 280/806
• CPC Class Codes: B60R 2021/01272 Belt tensioners
• CPC Class Codes: B60R 2022/1806 for buckles
• CPC Class Codes: B60R 2022/4473 using an electric retraction device combined with a spring B60R2022/444, B60R2022/4466
• CPC Class Codes: B60R 2022/4685 with means to adjust or regulate the tensioning force in relation to external parameters
• CPC Class Codes: B60R 21/0155 sensing belt tension
• CPC Class Codes: B60R 22/18 Anchoring devices

Abstract

A seat belt 11 for constraining an occupant to a seat is provided with both a tension varying means 12, 16 allowing a tension given to the seat belt 11 to vary, and a tension detecting means 15, 17 for detecting a tension of the seat belt 11. There is provided failure detecting means 18, which detects failures of at least one of the tension varying means 12, 16 and the tension detecting means 15, 17 by comparing the tension given by the tension varying means 12, 16 to the tension detected by the tension detecting means 15, 17, the difference in tensions thereof exceeding a predetermined value.

Claims

1. A seat belt device comprising:

a seat belt for constraining an occupant to a seat;

a tension varying means allowing a tension given to the seat belt to vary;

a tension detecting means for detecting a tension of the seat belt; and

failure detecting means for comparing the tension given by the tension varying means to the tension detected by the tension detecting means, to detect failures of at least one of the tension varying means and the tension detecting means.

2. The seat belt device according to claim 1,

wherein the seat belt is of three-point support type, one end thereof being supported at an electromotive retractor in such a manner as to be freely wound, the other end thereof being supported at a lap anchor part, and the midportion thereof being supported at a buckle stay part,

the tension varying means is provided at the electromotive retractor, and

the tension detecting means is provided at the lap anchor part.

3. The seat belt device according to claim 1,

wherein the seat belt is of three-point support type, one end thereof being supported at an electromotive retractor in such a manner as to be freely wound, the other end thereof being supported at a lap anchor part, and the midportion thereof being supported at a buckle stay part,

the tension varying means and the tension detecting means are arranged such that the tension varying means is provided at the retractor and the tension detecting means is provided at the buckle stay part, such that the tension varying means is provided at the buckle stay part and the tension detecting means is provided at the lap anchor part, or such that the tension varying means and the tension detecting means are provided at the buckle stay part,

the buckle stay part is provided with an attachment/detachment detecting means for detecting an attachment of the seat belt, and

the failure detecting means is allowed to be actuated when the attachment/detachment detecting means is detecting the attachment of the seat belt.