STRAP RETENTION DEVICE AND AIRBAG DEVICE

• US 20130038046A1
• Filed: 08/07/2012
• Published: 02/14/2013
• Est. Priority Date: 08/10/2011
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Japan GK
• Original Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Inuzuka, Koji, Noguchi, Atsushi
• Granted Patent: US 8,500,166 B2
• Time in Patent Office: Days
• US Class Current: 280/743.2
• CPC Class Codes: B23D 15/145 actuated by explosion
• CPC Class Codes: B60R 2021/23388 having ends which are movable or detachable during deployment
• CPC Class Codes: B60R 2021/2395 comprising means to control the venting
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/239 characterised by their venting means

Abstract

Provided are a strap retention device that can improve the ability to reliably cut a strap, and an airbag device. A strap retention device includes an anchor having a retaining portion for retaining a first end of a strap, and a flat portion in contact with a back surface of the strap; a strap restraint member joined to the anchor for restraining movement of the strap in a width direction; a cutter for cutting the strap on the flat portion; a squib for applying a driving force to the cutter to move the cutter in a direction of the flat portion; and a housing accommodating the cutter and the squib and joined to the anchor.

Claims

1. A strap retention device for releasably retaining a first end of a strap having a second end connected to a movable object, the strap retention device comprising:

an anchor having a retaining portion for retaining the first end of the strap, and a flat portion in contact with a back surface of the strap;

a strap restraint member joined to the anchor for restraining movement of the strap in a width direction;

a cutter for cutting the strap on the flat portion;

a squib for applying a driving force to the cutter to move the cutter in a direction of the flat portion; and

a housing accommodating the cutter and the squib and joined to the anchor.

2. The strap retention device according to claim 1,

wherein the cutter has a straight blade longer than a width of the strap, and a pressure receiving surface for receiving a combustion product generated by the squib.

3. The strap retention device according to claim 2,

wherein the cutter is positioned by a shear pin inserted from an outside of the housing.

4. The strap retention device according to claim 3,

wherein the strap restraint member includes a plate-like stopper disposed on the retaining portion to make the back surface of the strap be in contact with the flat portion, and a guide member joined to the anchor and forming a slit through which the strap passes, and

wherein the strap is cut at a position between the stopper and the guide member.

5. The strap retention device according to claim 1,

wherein the cutter includes a tubular cutter body disposed along an inner surface of the housing and having a diameter larger than the width of the strap, and a piston disposed at a rear end of the cutter body and having a pressure receiving surface for receiving a combustion product generated by the squib.

6. The strap retention device according to claim 5,

wherein the strap restraint member includes a body having a size capable of being disposed inside the cutter body and able to contact a surface of the strap, and claws formed on the body so as to be adjacent to both sides of the strap and engageable with the anchor;

and

wherein the strap is cut on an outside of the body.

7. The strap retention device according to claim 6,

wherein the body includes a flap formed so as to be foldable toward the cutter body in a flat shape and reducing movement of the piston before the squib is activated.

8. The strap retention device according to claim 1,

wherein the retaining portion includes a bolt inserted through the flat portion and penetrating the strap, and a nut threaded onto the bolt;

or

wherein the retaining portion includes a hook portion engageable with the first end of the strap formed in a loop.

9. The strap retention device according to claim 1,

wherein the housing includes a step portion for positioning a tip of the squib inserted therethrough, and an engaging portion engaged with a rear end of the squib by caulking, or a keeper for fixing the squib inserted into the housing.

10. The strap retention device according to claim 1,

wherein the strap is made of base fabric or webbing.

11. An airbag device comprising:

an airbag that is normally folded and is inflated and deployed in an emergency;

an inflator for supplying gas to the airbag;

a retainer for holding the airbag and the inflator; and

a strap retention device for releasably retaining a first end of the strap having a second end connected to the airbag,

wherein the strap retention device includes the strap retention device according to claim 1.

12. The airbag device according to claim 11,

wherein the retainer has an opening through which the first end of the strap is led outside;

and

wherein the strap retention device is disposed on an outer surface of the retainer at a position adjacent to the opening.