Airbag cushion assembly having a horn switch secured with a cushion strap

• US 5,727,812 A
• Filed: 11/19/1996
• Issued: 03/17/1998
• Est. Priority Date: 11/19/1996
• Status: Expired due to Fees

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Morton International Incorporated (Autoliv Incorporated)
• Inventors: Parker, Don L., Dykstra, John E., Johnson, David B., Lund, Patricia A.
• Primary Examiner(s): Ellis, Christopher P.
• Application Number:
  US08/752,356
• Time in Patent Office: 483 Days
• Field of Search: 280/231, 280/743.2, 280/728.1, 280/743.1, 200/61.54
• US Class Current: 280/731
• CPC Class Codes: B60R 21/201 Packaging straps or envelopes for inflatable members
• CPC Class Codes: B60R 21/2035 using modules containing inflator, bag and cover attachable to the steering wheel as a complete sub-unit steering wheel covers with tear lines B60R21/21656; assembling of modules B60R21/217
• CPC Class Codes: B60R 21/217 Inflation fluid source retainers, e.g. reaction canisters; Connection of bags, covers, diffusers or inflation fluid sources therewith or together

Abstract

An airbag cushion assembly including a horn switch unit secured to an airbag cushion with a cushion strap, with the cushion strap and horn switch unit cooperating to retain the airbag cushion in a deflated, folded position prior to mounting the airbag cushion assembly within an airbag module and prior to inflation of the airbag cushion. The horn switch unit defines a first elongated slot, a second elongated slot and a weakened portion rupturable upon a force created by inflation of the airbag cushion to break the horn switch unit between a first and a second elongated slots defined by the horn switch unit. The horn switch unit is positioned on the folded airbag cushion opposite the collar, with a first elongated tether of the cushion strap extending through the first slot of the horn switch unit to a distal end secured to the collar of the airbag cushion, and a second elongated tether extending through the second slot of the horn switch unit to a distal end secured to the collar of the airbag cushion.

Claims

1. A horn switch unit for use as part of an airbag cushion assembly having an inflatable folded airbag cushion and a first elongated tether and a second elongated tether extending from the airbag cushion, the horn switch unit comprising:

at least one horn switch for closing a horn switch circuit to activate a remote vehicle horn upon being compressed;

at least one rigid support plate secured to the at least one horn switch;

the horn switch unit defining a first elongated slot for receiving the first elongated tether of the airbag cushion assembly, a second elongated slot for receiving the second elongated tether of the airbag cushion assembly, and a weakened portion of the horn switch unit rupturable by a force produced by an inflating airbag cushion to break the horn switch unit between the first elongated slot and the second elongated slot;

whereby the horn switch unit can cooperate with the first elongated tether and the second elongated tether to retain the airbag cushion in a folded condition prior to inflation of the airbag cushion.

2. A horn switch unit according to claim 1 wherein the at least one horn switch comprises a membrane horn switch.

3. A horn switch unit according to claim 1 wherein:

the at least one horn switch comprises a single horn switch including a first main switch section and a second main switch section connected by spaced-apart narrowed first and second bridge members forming the weakened portion of the horn switch unit; and

the at least one rigid support plate comprises a single rigid support plate secured to the horn switch and defining the first elongated slot between the first and the second bridge members and defining the second elongated slot between the first and the second bridge members, the support plate also defining a tear seam between the first and the second elongated slots, the tear seam also acting as the weakened portion of the horn switch.

4. A horn switch unit according to claim 1 wherein:

the at least one horn switch comprises a first horn switch defining an elongated aperture, and a second horn switch defining an elongated aperture; and

the at least one rigid support plate comprises a single rigid support plate secured to both the first horn switch and the second horn switch, and defining the first elongated slot below the elongated aperture of the first horn switch and defining the second elongated slot below the elongated aperture of the second horn switch, the support plate also defines a tear seam between the first and the second elongated slots, the tear seam being the weakened portion of the horn switch.

5. A horn switch unit according to claim 1 wherein:

the at least one horn switch comprises a single horn switch including a first main switch section and a second main switch section connected by spaced-apart narrowed first and second bridge members forming the weakened portion of the horn switch; and

the at least one rigid support plate includes a first rigid support plate secured to the first main switch section of the horn switch and defining the first elongated slot between the first and the second bridge members and a second rigid support plate secured to the second main switch section of the horn switch and defining the second elongated slot between the first and the second bridge members.

6. A horn switch unit according to claim 5 wherein:

A) the first support plate includes,

a base supporting the first main switch section of the horn switch and defining the first elongated slot,

a peripheral wall extending upwardly from and generally perpendicular to the base, and peripherally retaining the first main switch section of the horn switch, the peripheral wall defining two spaced-apart gaps allowing the first and the second bridge members to extend through the peripheral wall, and

means retaining the first main switch section of the horn switch within the peripheral wall, securing the first main switch section to the first support plate; and

B) the second support plate includes,

a base supporting the second main switch section of the horn switch and defining the second elongated slot,

a peripheral wall extending upwardly from and generally perpendicular to said base, and peripherally retaining the second main switch section of the horn switch, said peripheral wall defining two spaced-apart gaps allowing the first and the second bridge members to extend through said peripheral wall, and

means retaining the second main switch section of the horn switch within said peripheral wall, securing the second main switch section to the second support plate.

7. A cushion strap for use as part of an airbag cushion assembly also including a folded inflatable airbag cushion having a collar defining an open mouth for receiving inflation fluid, a retainer ring positioned within the airbag cushion over the collar and having a plurality of spaced-apart studs extending through a plurality of stud holes in the collar, and a horn switch unit positioned on the folded airbag cushion generally opposite the collar, the horn switch unit defining a first elongated slot, a second elongated slot and a weakened portion rupturable upon inflation of the airbag cushion for breaking the horn switch unit between the first and the second elongated slots, the cushion strap comprising:

a collar defining a plurality of stud holes for receiving the plurality of spaced-apart studs extending from the retainer ring to secure the collar of the cushion strap to the collar of the airbag cushion;

a first elongated tether sized to extend from a first end secured to the collar of the cushion strap, and through the first slot of the horn switch unit to a distal end defining at least two stud holes for receiving at least two of the plurality of spaced-apart studs extending from the retainer ring to secure the distal end to the collar of the cushion strap; and

a second elongated tether sized to extend from a first end secured to the collar of the cushion strap generally opposite the first end of the first elongated tether, and through the second slot of the horn switch unit to a distal end defining at least two stud holes for receiving at least two of the plurality of spaced-apart studs extending from the retainer ring to secure said distal end to the collar of the cushion strap;

whereby the first elongated tether, the second elongated tether and the horn switch unit will cooperate to retain the airbag cushion in a folded condition prior to inflation of the airbag cushion.

8. A cushion strap according to claim 7 wherein the first elongated tether includes a narrowed portion for engaging the first slot of the horn switch unit, the narrowed portion located generally midway between the first end and the distal end of the first elongated tether, and the second elongated tether also includes a narrowed portion for engaging the second slot of the horn switch unit, said narrowed portion located generally midway between the first end and the distal end of the second elongated tether.

9. A airbag cushion assembly for use with a horn switch unit defining a first elongated slot, a second elongated slot and a weakened portion rupturable upon inflation of an airbag cushion for breaking the horn switch unit between the first and the second elongated slots, the airbag cushion assembly including:

a folded, inflatable airbag cushion having a collar defining an open mouth of the airbag cushion for receiving inflation fluid;

a retainer ring positioned within the airbag cushion over the collar and having a plurality of spaced-apart studs extending through a plurality of stud holes in the collar;

a first elongated tether sized to extend from a first end secured to the collar of the airbag cushion, and through the first slot of the horn switch unit when the horn switch unit is positioned on the folded airbag cushion generally opposite the collar, to a distal end defining at least two stud holes for receiving at least two of the plurality of spaced-apart studs extending from the retainer ring to secure the distal end to the collar; and

a second elongated tether sized to extend from a first end secured to the collar of the airbag cushion generally opposite the first end of the first elongated tether, and through the second slot of the horn switch unit to a distal end defining at least two stud holes for receiving at least two of the plurality of spaced-apart studs extending from the retainer ring to secure said distal end to the collar;

whereby the first elongated tether, the second elongated tether and the horn switch unit will cooperate to retain the airbag cushion in a folded condition prior to inflation of the airbag cushion.

10. An airbag cushion assembly according to claim 9 wherein the first elongated tether of the cushion strap includes a narrowed portion for engaging the first slot of the horn switch unit, the narrowed portion located generally midway between the first end and the distal end of the first elongated tether, and the second elongated tether of the cushion strap also includes a narrowed portion for engaging the second slot of the horn switch unit, said narrowed portion located generally midway between the first end and the distal end of the second elongated tether.

11. An airbag cushion assembly according to claim 9 wherein the cushion strap further includes a collar defining a plurality of stud holes receiving the plurality of spaced-apart studs extending from the retainer ring and securing the collar of the cushion strap to the collar of the airbag cushion, with the first end of the first elongated tether secured to the collar of the cushion strap, and the first end of the second elongated tether secured to the collar of the cushion strap.

12. An airbag cushion assembly comprising:

A) a folded, inflatable airbag cushion having a collar defining an open mouth of the airbag cushion for receiving inflation fluid;

B) a cushion strap including a first elongated tether extending from a first end secured to the collar of the airbag cushion to a distal end, and a second elongated tether extending from a first end secured to the collar of the airbag cushion to a distal end; and

C) a horn switch unit positioned on top of the folded airbag cushion generally opposite the collar and including,

1) at least one horn switch for closing a horn switch circuit to activate a remote vehicle horn upon being compressed, and

2) at least one rigid support plate secured to the at least one horn switch, with

the horn switch unit defining a first elongated slot with the first elongated tether of the cushion strap extending through the first elongated slot of the horn switch unit and the distal end of the first elongated tether secured to the collar of the airbag cushion, the horn switch unit defining a second elongated slot with the second elongated tether of the cushion strap extending through the second elongated slot of the horn switch unit and the distal end of the second elongated tether secured to the collar of the airbag cushion, the horn switch unit also defining a weakened portion rupturable upon a force created by inflation of the airbag cushion to break the horn switch unit between

the first and the second elongated slots;

whereby the first elongated tether, the second elongated tether and the horn switch unit cooperate to retain the airbag cushion in a folded condition prior to inflation of the airbag cushion.

13. An airbag cushion assembly according to claim 12 wherein:

the at least one horn switch of the horn switch unit comprises a single horn switch including a first main switch section and a second main switch section connected by spaced-apart first and second narrowed bridge members forming the weakened portion of the horn switch unit; and

the at least one rigid support plate comprises a single rigid support plate secured to the horn switch and defining the first and the second elongated slots between the first and the second bridge members, with the first and the second tethers of the airbag cushion assembly extending between the first and the second bridge members, the support plate also defining a tear seam between the first and the second elongated slots, the tear seam also forming the weakened portion of the horn switch.

14. An airbag cushion assembly according to claim 12 wherein:

the at least one horn switch of the horn switch unit comprises a first horn switch defining an elongated aperture and a second horn switch defining an elongated aperture; and

the at least one rigid support plate comprises a single rigid support plate secured to both the first and the second horn switches and defining the first elongated slot below the elongated aperture of the first horn switch and defining the second elongated slot below the elongated aperture of the second horn switch, with the first tether of the airbag cushion assembly extending through the elongated aperture of the first horn switch and the first elongated slot of the support plate and the second tether extending through the elongated aperture of the second horn switch and the second elongated slot of the support plate, the support plate also defining the weakened portion of the horn switch in the form of a tear seam between the first and the second elongated slots.

15. An airbag cushion assembly according to claim 12 wherein:

the at least one horn switch of the horn switch unit comprises a single horn switch including a first main switch section and a second main switch section connected by spaced-apart first and second narrowed bridge members forming the weakened portion of the horn switch; and

the at least one rigid support plate includes a first rigid support plate secured to the first main switch section of the horn switch and defining the first elongated slot between the first and the second bridge members and a second rigid support plate secured to the second main switch section of the horn switch and defining the second elongated slot between the first and the second bridge members, with the first and the second tether of the cushion assembly extending between the first and the second bridge members.

16. An airbag cushion assembly according to claim 15 wherein the cushion strap further includes a collar secured to the collar of the airbag cushion, with the first end of the first elongated tether secured to the collar of the cushion strap and the distal end of the first elongated tether secured to the collar of the cushion strap, and the first end of the second elongated tether secured to the collar of the cushion strap and the distal end of the second elongated tether secured to the collar of the cushion strap.

17. An airbag cushion assembly according to claim 16 further including:

a retainer ring having a plurality of spaced-apart studs extending from the retainer ring through a plurality of stud holes in the collar of the airbag cushion, and through a plurality of stud holes defined by the collar of the cushion strap, securing the collar of the cushion strap to the collar of the airbag cushion;

the distal end of the first elongated tether defining at least two stud holes receiving at least two of the plurality of spaced-apart studs extending from the retainer ring securing the distal end of the first elongated tether to the collar of the cushion strap; and

the distal end of the second elongated tether defining at least two stud holes receiving at least two of the plurality of spaced-apart studs extending from the retainer ring, securing the distal end of the second elongated tether to the collar of the cushion strap.

18. An airbag cushion assembly according to claim 15 further including:

a retainer ring having a plurality of spaced-apart studs extending from the retainer ring through a plurality of stud holes in the collar of the airbag cushion;

the distal end of the first elongated tether defining at least two stud holes receiving at least two of the plurality of spaced-apart studs extending from the retainer ring securing the distal end of the first elongated tether to the collar of the airbag cushion; and

the distal end of the second elongated tether defining at least two stud holes receiving at least two of the plurality of spaced-apart studs extending from the retainer ring, securing the distal end of the second elongated tether to the collar of the airbag cushion.

19. An airbag module comprising:

A) a module baseplate;

B) an airbag cushion assembly secured to the module baseplate, the airbag module assembly including,

1) a folded, inflatable airbag cushion having a collar defining an open mouth of the airbag cushion for receiving inflation fluid,

2) a cushion strap including a first elongated tether extending from a first end secured to the collar of the airbag cushion to a distal end, and a second elongated tether extending from a first end secured to the collar of the airbag cushion to a distal end, and

3) a horn switch unit positioned on top of the folded airbag cushion generally opposite the collar and including,

a) at least one horn switch for closing a horn switch circuit to activate a remote vehicle horn upon being compressed, and

b) at least one rigid support plate secured to the at least one horn switch, with

the horn switch unit defining a first elongated slot with the first elongated tether of the cushion strap extending through the first elongated slot of the horn switch unit and the distal end of the first elongated tether secured to the collar of the airbag cushion, the horn switch unit also defining a second elongated slot with the second elongated tether of the cushion strap extending through the second elongated slot of the horn switch unit and the distal end of the second elongated tether secured to the collar of the airbag cushion, the horn switch unit additionally defining a weakened portion rupturable upon a force created by inflation of the airbag cushion to break the horn switch unit between the first and the second elongated slots,

whereby the first elongated tether, the second elongated tether and the horn switch unit cooperate to retain the airbag cushion in a folded condition prior to inflation of the airbag cushion;

C) a module cover positioned over the airbag cushion assembly and secured to the module baseplate, the module cover defining at least one tear seam positioned over the weakened portion of the horn switch unit; and

D) an airbag inflator secured to the module baseplate with a portion of the airbag inflator defining a plurality of gas exhaust ports positioned within the mouth of the airbag cushion.