Inflator device with integral clamp stop

Abstract

A vehicular safety restraint inflator device, the inflator device includes a tubular housing to provide inflation gas to inflate an associated inflatable restraint device and a toroidal clamp stop positioned on the tubular inflator housing. The clamp stop serves to provide a hard stop for an inflator attachment clamp to secure the inflator device within an airbag module and thus to minimize or avoid undesired lateral movement of the inflator device within a module assembly.

Claims

1. A vehicular safety restraint inflator device, the inflator device comprising: a tubular housing to provide inflation gas to inflate an associated inflatable restraint device; and a toroidal clamp stop positioned on the tubular housing to provide a hard stop for an inflator attachment clamp to secure the inflator device within an airbag module; wherein a reactive material is contained within the tubular housing and reaction of the reactive material within the tubular housing generates an increase in pressure within the tubular housing, the inflator device additionally comprising: an overwrap about at least a portion of the tubular housing to form an inflator assembly that withstands the pressure generated within the tubular housing upon reaction of the reactive material, the overwrap comprising a composite of fibers and a resin matrix system and wherein the toroidal clamp stop comprises a toroidal-shaped element disposed on the tubular housing with the composite overwrap disposed thereover.

2. The vehicular safety restraint inflator device of claim 1 wherein the inflator device comprises a hybrid inflator.

3. The vehicular safety restraint inflator device of claim 1 wherein the tubular housing is incapable of withstanding the pressure generated within the tubular housing upon reaction of the reactive material without support provided by the overwrap.

4. The vehicular safety restraint inflator device of claim 1 wherein the tubular housing has a length to diameter ratio of at least 1:1.

5. A vehicular safety restraint inflator device, the inflator device comprising: a tubular housing to provide inflation gas to inflate an associated inflatable restraint device; and a toroidal clamp stop positioned on the tubular housing to provide a hard stop for an inflator attachment clamp to secure the inflator device within an airbag module; wherein a reactive material is contained within the tubular housing and reaction of the reactive material within the tubular housing generates an increase in pressure within the tubular housing, the inflator device additionally comprising: an overwrap about at least a portion of the tubular housing to form an inflator assembly that withstands the pressure generated within the tubular housing upon reaction of the reactive material, the overwrap comprising a composite of fibers and a resin matrix system and wherein the toroidal clamp stop comprises a raised build-up of the composite onto the tubular housing.

6. The vehicular safety restraint inflator device of claim 5 wherein the inflator device comprises a hybrid inflator.

7. The vehicular safety restraint inflator device of claim 5 wherein the tubular housing is incapable of withstanding the pressure generated within the tubular housing upon reaction of the reactive material without support provided by the overwrap.

8. The vehicular safety restraint inflator device of claim 5 wherein the tubular housing has a length to diameter ratio of at least 1:1.

9. A hybrid inflator device that upon actuation provides a supply of inflation gas to inflate an associated inflatable restraint device, the inflator device comprising: a tubular hybrid inflator housing containing a supply of reactive material and a supply of pressurized gas supplying material; and an overwrap about at least a portion of the tubular hybrid inflator housing to form a hybrid inflator device that withstands pressure generated within the tubular hybrid inflator housing upon reaction of the reactive material, the overwrap comprising a composite of fibers and a resin matrix system, the overwrap forming a toroidal clamp stop disposed around the tubular hybrid inflator housing to provide a hard stop for an inflator attachment clamp to secure the inflator device within an airbag module.

10. The vehicular safety restraint inflator device of claim 9 wherein the tubular hybrid inflator housing is incapable of withstanding the pressure generated within the tubular hybrid inflator housing upon reaction of the reactive material without support provided by the overwrap.

11. The vehicular safety restraint inflator device of claim 9 wherein the toroidal clamp stop comprises a raised build-up of the composite onto the tubular hybrid inflator housing.

12. The vehicular safety restraint inflator device of claim 9 wherein the tubular hybrid inflator housing has a length to diameter ratio of at least 1:1.

13. In an inflator device that upon actuation provides a supply of inflation gas to inflate an associated inflatable restraint device, the inflator device including a tubular inflator housing containing a supply of reactive material, the inflator device having an overwrap comprising a composite of fibers and a resin matrix system disposed over at least a portion of the inflator housing, the improvement comprising: a clamp stop disposed around an exterior of the tubular inflator housing, the clamp stop providing a hard stop for an inflator attachment clamp to secure the inflator device within an airbag module, wherein the clamp stop comprises a toroidal-shaped element and wherein the overwrap extends over the toroidal-shaped element.

14. The improvement of claim 13 wherein the inflator device comprises a hybrid inflator.

15. The improvement of claim 13 wherein the inflator device comprises an elongated tubular form.

16. In an inflator device that upon actuation provides a supply of inflation gas to inflate an associated inflatable restraint device, the inflator device including a tubular inflator housing containing a supply of reactive material, the inflator device having an overwrap comprising a composite of fibers and a resin matrix system disposed over at least a portion of the inflator housing, the improvement comprising: a clamp stop disposed around an exterior of the tubular inflator housing, wherein the clamp stop comprises a toroidal-shaped build-up of the composite onto the tubular inflator housing, the clamp stop providing a hard stop for an inflator attachment clamp to secure the inflator device within an airbag module.

17. The improvement of claim 16 wherein the inflator device comprises a hybrid inflator.

18. The improvement of claim 16 wherein the inflator device comprises an elongated tubular form.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a fragmentary perspective view showing a vehicular safety restraint inflator device in accordance with an embodiment of the invention.

(2) FIG. 2 is a fragmentary side view showing a vehicular safety restraint inflator device in accordance with an embodiment of the invention.

(3) FIG. 3 is a fragmentary cross sectional view showing a vehicular safety restraint inflator device in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(4) FIG. 1 illustrates a vehicular safety restraint inflator device, generally designated with the reference numeral 10, and in accordance with a one embodiment of the invention. While the invention will be described hereinafter with particular reference to passenger side inflator devices and associated airbag inflatable restraint system installations, it will be understood that the invention has general applicability to other types or kinds of airbag assemblies including, for example, single stage passenger, single or dual stage driver side or side airbag assemblies such as for automotive vehicles including vans, pick-up trucks, and particularly automobiles.

(5) The inflator device 10 has a generally cylindrical external outline and includes a generally cylindrical housing 12, such as having a tubular elongated form. The housing 12 desirably may be formed or made of metal or steel or other materials as may be desired for particular applications.

(6) The housing 12 can provide inflation gas to inflate an associated inflatable restraint device, e.g., airbag cushion, such as in a manner know in the art. In the case of a common type of hybrid inflator, inflation gas provided by the housing may, for example, take the form of stored pressurized gas such as may be heated or otherwise appropriately expanded via contact with reaction products from a reactive material also contained, included or a part of the inflator device. Such reaction products in accordance with embodiments of the invention may, for example, include: gas at least in part formed by or from the reactive material, heat produced by the reaction of the reactive material and combinations of such gas and heat.

(7) The inflator device 10 further includes a composite material, such as composed of high strength fibers and a resin matrix system to form an overwrap thickness 14 around, about and/or over at least selected desired portion or portions of the housing 12.

(8) As will be appreciated by those skilled in the art and guided the teachings herein provided, through the inclusion of an overwrap of such composite material, the housing 12 can desirably be fabricated or formed of metal, such as drawn steel or aluminum, for example, wherein the metal is relatively thin as compared to conventional inflator housings without such an overwrap. For example, whereas conventional inflator metal housings are commonly 1.5 to 3 mm thick, the invention permits the utilization of metal housing members having a thickness of less than 1.5 mm preferably less than 1 mm thick.

(9) A high pressure capable structure is created or formed by overwrapping the inflator housing 12 with a selected material such as having the form of a composite.

(10) The overwrap process can generally involve installing or placing the inflator housing 12 in a filament winding machine and subsequently filament winding a composite material, such as composed of high strength fibers and a resin matrix system, around, about and/or over the housing 12 to form the desired overwrap thickness 14 about the housing 12.

(11) Various fiber materials such as known in the art can be used. For improved economics, in certain embodiment the use of glass fiber or basalt fiber materials may be preferred.

(12) The composite overwrapped inflator housing assembly can then be treated, such as by curing (e.g., UV or thermal curing) or melt processing of thermal plastic resins, for example, to form an inflator assembly that withstands the pressure generated within the inflator device upon actuation such as upon reaction of reactive material therein contained but wherein the inflator housing is itself incapable of withstanding the pressure generated within the housing upon reaction of reactive material therein contained without support provided by the composite overwrap.

(13) In accordance with one aspect of the invention, processing times can desirably be reduced or minimized by utilizing a UV cure resin system instead of common thermoset, elevated temperature cure resin systems. For example, a typical elevated temperature cure cycle involves heating at 120 C. for 90 minutes, while a UV cure system can effect cure in under 15 seconds when using an optically transparent fiber such as E-glass. UV curing has the additional safety advantage of avoiding subjecting the reactive material to elevated temperature such as could result in inadvertent actuation or other undesirable degradation of energetic materials, such as included or associated with an initiator, a pyrotechnic gas generant material, for example.

(14) The inflator device 10 includes a clamp stop 20 positioned on the tubular inflator housing 12. The clamp stop 20 acts, serves or otherwise provides a hard stop for an inflator attachment clamp (such as a circular or ring-type clamp shown as item 22) such as to appropriately secure the inflator device 10 in position or place such as within an associated an airbag module.

(15) As will be appreciated by those skilled in the art and guided by the teachings herein provided, such circular or ring-type clamps can desirably secure an associated inflator device within a module in a manner conducive to adaptation to different sized inflator devices in a relatively simple and expedient manner.

(16) The clamp stop 20 as shown in the illustrated embodiment can take the form of a raised feature such as to provide or form a hard stop for the attachment clamp 22. In accordance with one aspect of the invention, the clamp stop is desirably formed or created as an integral component of the inflator device. Further, the clamp stop desirably can serve to minimize and preferably avoid or prevent lateral movement or sliding of the inflator device such as, upon actuation of the inflator device and the occurrence of a deployment event, could otherwise lead to displacement or sliding of the inflator device from the hold or retention provided by the attachment clamp.

(17) The incorporation and use of such a clamp stop can desirably reduce or minimize either or both the number of clamps required or used in a particular application and the clamp force provided or resulting from the used clamp or clamps. For example, in accordance with one aspect of the invention, the use of a single clamp of the above-identified circular or ring-type clamp is effective to realize desired inflation device retention without significant inflator device lateral movement upon inflator device actuation and deployment. It is to be understood, however, that if desired, the invention could be employed in assemblies that include two, three or more attachment clamps. Further, in assemblies with two or more attachment clamps, not each attachment clamp need have an associated clamp stop in accordance with the invention in order to obtain or realize at least a portion or some of one or more of the benefits realizable through the practice of the invention.

(18) The clamp stop 20 comprises or is formed by or as a raised, build-up of the composite onto the inflator housing 12. The shape of the clamp stop 20, e.g., the cross sectional profile of the raised feature, can be but is not restricted to, round or square. Further, such raised feature can be situated or placed at any desired or suitable location on the inflator housing 12 and can be of any desired or suitable relative height. In accordance with one aspect of the invention, such a raised feature can desirably be of a height of from 1 mm to 2.5 mm, where the height (h) is shown in FIG. 1.

(19) While the invention has been described above making reference to an embodiment wherein the clamp stop comprises or is formed by or as a raised, build-up of the composite onto the inflator housing, those skilled in the art and guided by the teachings herein provide will understand and appreciate that the broader practice of the invention is not necessarily so limited. For example, if desired, a clamp stop can be at least in part formed or provided via the inclusion of an added element or component to the inflator assembly.

(20) For example, FIG. 2 illustrates a vehicular safety restraint inflator device, generally designated with the reference numeral 210, and in accordance with another embodiment of the invention.

(21) The inflator device 210, similar to the inflator device 10 described above, has a generally cylindrical external outline and includes a generally cylindrical housing 212, such as having a tubular elongated form. The housing 212 desirably may be formed or made of metal or steel or other materials as may be desired for particular applications.

(22) The inflator device 210, further similar to the inflator device 10 described above, further includes a composite material, such as composed of high strength fibers and a resin matrix system to form an overwrap thickness 214 around, about and/or over at least selected desired portions of the housing 212.

(23) The inflator device 210, also similar to the inflator device 10 described above, includes a clamp stop 220 positioned on the tubular inflator housing 212. The clamp stop 220 acts, serves or otherwise provides a hard stop for an inflator attachment clamp (such as a circular or ring-type clamp shown as item 222) such as to appropriately secure the inflator device 210 in position or place such as within an associated an airbag module.

(24) The inflator device 210 at least in part differs from the inflator device 10 in that the clamp stop 220 is at least in part formed by or includes a toroidal-shaped element 221 disposed on the tubular inflator housing 212 with the composite overwrap 214 disposed thereover. The element 221 can be formed of or from various suitable materials including metals, plastics, ceramics and the like and the broader practice of the invention is not necessarily limited by or to the use of specific materials of construction.

(25) While the invention has been described above making references to embodiments incorporating a single clamp stop for use in conjunction with an associated clamp, the broader practice of the invention is not necessarily so limited. To that end, FIG. 3 illustrates an alternative embodiment wherein multiple clamp stops are used in conjunction with an attachment clamp. More specifically, FIG. 3 illustrates a vehicular safety restraint inflator device, generally designated with the reference numeral 310.

(26) The inflator device 310, similar to the inflator device 10 described above, has a generally cylindrical external outline and includes a generally cylindrical housing 312, such as having a tubular elongated form. The housing 312 desirably may be formed or made of metal or steel or other materials as may be desired for particular applications.

(27) The inflator device 310, further similar to the inflator device 10 described above, further includes a composite material, such as composed of high strength fibers and a resin matrix system to form an overwrap thickness 314 around, about and/or over at least selected desired portion or portions of the housing 312.

(28) The inflator device 310 at least in part differs from the inflator device 10 in that the inflator device 310 includes first and second clamp stops 320a and 320b positioned on or about the tubular inflator housing 312. The clamp stops 320a and 320b act, serve or otherwise provide a hard stop on opposed sides of an inflator attachment clamp (such as a circular or ring-type clamp shown as item 322) such as to appropriately secure the inflator device 310 in position or place such as within an associated an airbag module.

(29) The invention desirably provides systems or assemblies that provide increased or improved inflator device retention such as by reducing, minimizing or, preferably, avoiding lateral movement or sliding of inflator devices upon actuation and deployment.

(30) The invention desirably reduces system level costs such as by either or both: 1) facilitating the incorporation and use of lower cost inflator attachment features or elements, e.g., clamps, and 2) reducing or minimizing the number of inflator attachment features or elements, e.g., clamps, required to effect desired inflator attachment and retention.

(31) The invention desirably reduces costs associated with either or both assembly and production such as by facilitating the incorporate and use of circular or ring-type inflator attachment clamps.

(32) The invention illustratively disclosed herein suitably may be practiced in the absence of any element, part, step, component, or ingredient which is not specifically disclosed herein.

(33) While in the foregoing detailed description this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purposes of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of the invention.