Knee-protecting airbag device

• US 7,201,395 B2
• Filed: 12/24/2003
• Issued: 04/10/2007
• Est. Priority Date: 12/27/2002
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Nagata, Atsushi, Sato, Yuji, Mizuno, Yoshio, Nakayama, Kazuhiro
• Primary Examiner(s): Dickson; Paul N.
• Assistant Examiner(s): MCCREARY, LEONARD
• Application Number:
  US10/744,134
• Publication Number:
  US 20040164527A1
• Time in Patent Office: 1,203 Days
• Field of Search: 280/728.1, 280/728.2, 280/730.1, 280/743.1, 280/743.2, 280/752, 280/753
• US Class Current: 280/730.1
• CPC Class Codes: B60R 2021/161 characterised by additional means for controlling deployment trajectory
• CPC Class Codes: B60R 2021/23169 specially adapted for knee protection
• CPC Class Codes: B60R 2021/23316 Inner seams, e.g. creating separate compartments or used as tethering means
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 21/205 in dashboards
• CPC Class Codes: B60R 21/206 in the lower part of dashboards, e.g. for protecting the knees
• CPC Class Codes: B60R 21/2171 specially adapted for elongated cylindrical or bottle-like inflators with a symmetry axis perpendicular to the main direction of bag deployment, e.g. extruded reaction canisters B60R21/2176 takes precedence
• CPC Class Codes: B60R 21/231 characterised by their shape, construction or spatial configuration
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/2342 Tear seams
• CPC Class Codes: B60R 21/237 characterised by the way they are folded

Abstract

In a knee-protecting airbag device according to the present invention, an airbag folded and housed in undeployed condition protrudes rearward from a housing case to deploy upward and protects knees of a driver upon inflow of inflation gas. The airbag includes a cover portion for covering a vehicle'"'"'s rear side of an area proximate to the key cylinder upon completion of deployment, and a general portion in the upper edge side of the airbag except the cover portion. Kinetic energy of the cover portion as deployed in a position of complete deployment is restrained compared with a kinetic energy of the general portion as deployed in a position of complete deployment. This restraint is achieved by reducing amount of inflation gas flowing into the cover portion. The knee-protecting airbag device of the present invention prevents the inflating airbag from contacting with key accessories hung down from an ignition key inserted into the key cylinder in a manner to cause gas leakage.

Claims

1. A knee-protecting airbag device located below a steering column in front of a driver'"'"'s seat and, at a lower side of a key cylinder into which an ignition key with an accessory is inserted, the airbag device comprising:

a housing case located below the steering column;

an airbag folded and housed in the housing case in an undeployed condition, and upon inflow of inflation gas, the airbag protruding rearward from the housing case to deploy upward in order to protect the knees of a seated driver;

the airbag comprising;

a cover portion located in a left or right corner in an upper edge side of the airbag as completely deployed, the cover portion being for covering a vehicle'"'"'s rear side of an area proximate to the key cylinder; and

a general portion, the general portion being the upper edge side of the airbag as completely deployed other than the cover portion; and

a damage prevention means for preventing the airbag from being damaged by the key accessory and leaking gas when the inflated airbag contacts with the key accessory directly

wherein;

the airbag comprises a primary inflatable portion, the primary inflatable portion being inflatable from an initial stage of inflow of inflation gas, and including the general portion as a part of the primary inflatable portion, and a secondary inflatable portion, the secondary inflatable portion starting to inflate around when the primary inflatable portion completes inflation,

the cover portion is located either in an area of the secondary inflatable portion of the airbag, or in an area near the secondary inflatable portion, thereby constituting the damage prevention means,

upon completion of inflation by the primary inflatable portion, the upper edge side of the airbag deploys up to a position of the upper edge side at complete inflation of the airbag with the cover portion remaining uninflated and in a thin plate-shape.

2. The knee-protecting airbag device according to claim 1, wherein:

the airbag as completely inflated takes a substantially plate shape including a column side wall located toward the steering column and a driver'"'"'s side wall located toward the driver'"'"'s seat; and

the primary inflatable portion and the secondary inflatable portion are formed by stitching yarn, the stitching yarn breakably stitching the column cover side wall and the driver'"'"'s side wall together.