WO2001013484A2

WO2001013484A2 - Die cast connector adapter and inflator assembly incorporating the same

Info

Publication number: WO2001013484A2
Application number: PCT/US2000/020833
Authority: WO
Inventors: Steven L. Ludeke; Robb C. Isbell; David A. Bilbrey
Original assignee: Atlantic Research Corporation
Priority date: 1999-08-12
Filing date: 2000-07-31
Publication date: 2001-02-22
Also published as: WO2001013484A3

Abstract

A die cast connector adapter (1) having a substantially cylindrical adapter body includes a first portion (10a) having a first outer diameter and a second portion (10b) having a second outer diameter. The adapter body has an inner cavity including, from one end thereof to the other, a frustoconical section (16) preferably substantially coincident with the second portion, a cylindrical section (14) and a contour cut-out section (22). The frustoconical section and cylindrical section are adapted to receive the correspondingly-shaped end of an initiator (60) for an air-bag inflator and the contour cut-out section is adapted to receive, in keyed fashion, a connector for mating with pins on the initiator. An inflator assembly incorporating the connector adapter is also disclosed.

Description

DIE CAST CONNECTOR ADAPTER AND INFLATOR ASSEMBLY INCORPORATING

THE SAME

The piesent invention is dπected to mechanical connectors and adapters, and more particularly to an improved connector adapter for mounting an initiator of an air bag to an inflator and providing improved mechanical and electrical connection therefor.

BACKGROUND OF THE INVENTION

Air bags are becoming increasingly populai safety devices in passenger vehicles. These devices often include an inflator having a pressure vessel containing a compressed gas. When it is desired for the inflator to operate and thereby expand a bag connected thereto to protect a passenger πdmg in the vehicle, an electric signal is generated and passed to an initiator disposed proximate the pressure vessel and the gas stored therein The initiator typically initiates the combustion of an igniter that, in turn, heats the compressed gas, thereby expanding same and quickly inflating the attached air bag Unless the vehicle is involved m a collision, the air bag should not inflate. On the other hand, the air bag is expected to inflate under certain crash conditions, even after being in an idle state for a long period of time (perhaps years) Accordingly, it is desirable that the components of the air bag remain in an operable and reliable condition over long periods of time.

Additionally, because air bags are now being installed in more and more vehicles of all types, economic realities require that the device be as inexpensive as possible yet still adequately perform.

Conventional airbag inflator initiators, like the one depicted in U.S. Patent 4,170,939 to Hoheisel et al. for example, are positioned relative to a housing via a plastic insert. This plastic insert typically must be molded to receive on one end an initiator or igniter and, on the other end, a connector for making electrical connection with the pins of the initiator or igniter Additionally, the housing of the inflator itself must be specially machined to properly receive and retain the plastic insert The plastic insert itself along with the necessary special machining adds unnecessary, and therefore undesirable, component and labor costs to the overall inflator SUMMARY OF THE INVENTION

In view of the unnecessary expenses and other disadvantages of the pπor art plastic assemblies, it is an object of the present invention to provide a simple and economical means of providing mechanical and electπcal connection for an initiator of an air bag inflator In accordance with the present invention there preferably is provided a die cast connector adapter that is shaped to receive both an initiator of an inflator and an electrical connector in the proper oπentation to mate with the pins of the initiator.

Further in accordance with the present invention the connector adapter preferably is configured to be easily assembled with a base plate of a pressure vessel of the inflator and to be held securely thereto

Still further in accordance with the present invention the die cast connector adapter preferably provides mechanical protection and EMI RFI shielding to the initiator pπor to installation thereof in an inflator assembly.

Generally, the connector adapter of the present invention preferably compπses a main body having a stepped substantially cyhndπcal outer shape which mates cleanly with a corresponding hole provided in a base plate of a pressure vessel. The stepped structure of the outer surface of the connector adapter ensures proper positioning of the initiator and the connector adapter at the correct height for assembly and sealing. This feature further supports the connector adapter in the base plate against the internal pressures of the pressure vessel The mteπor of the connector adapter preferably is provided with a frustoconical shape at one end thereof that leads to a cyhndπcal bore, which combination of shapes preferably matches the outer configuration of the initiator, whereby the initiator can be seated securely therein. At an opposing inteπor end of the connector adapter there preferably is provided a contoured cut-out that ensures the proper oπentation of a connector when the connector is mated with the pms of the initiator

In final assembly, the initiator is seated in the connector adapter with its pins accessible via the contoured cut-out and the connector adapter is seated in the hole of the base plate of the pressure vessel. An initiator sleeve, preferably including an O-πng, covers the end of the initiator opposite the pin end and is secured to the base plate thereby providing an air-tight seal The instant invention provides a simple and inexpensive device to secure an initiator to an inflator assembly while also providing protection to the initiator prior to assembly and ensuπng proper oπentation of an electrical connector when it is mated with the pins of the initiator.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more fully understood upon reading the following Detailed Descπption in conjunction with the accompanying figures, in which reference numerals are used consistently to indicate like elements, and in which:

Fig. 1 is a rear view of the adapter of the present invention;

Figs 2 and 3 are cross-sectional views through II-II and III-III, respectively, of Fig. 1;

Fig. 4 is a side view of the adapter of the present invention; Figs 5-7 are cross-sectional views through V-V, VI- VI and VII- VII, respectively, of Fig

4; and

Fig. 8 illustrates the adapter of the present invention incorporated with a base plate of an inflator.

DETAILED DESCRIPTION OF THE INVENTION Referπng now to Figs. 1-7, the connector adapter in accordance with the present invention is descπbed Connector adapter 1 preferably has a cyhndπcal main body 10 having two portions 10a and 10b having different outer diameters, with a transaction step 20 at the junction of the two diameters Preferably the step is on the order of about 1 mm (2 mm on the diameter) In the prefeπed embodiment the connector adapter 1 is die cast zinc or aluminum both of which are relatively inexpensive and workable metals.

On the inteπor of the connector adapter 1 there is provided a cavity 12 having a plurality of differently shaped portions. At one end of the connector adapter there is a cylmdπcal bore portion 14 that opens up to a frustoconical portion 16. This portion of the cavity 12 preferably corresponds to the outer shape of an initiator 60, as can be seen easily in Fig. 8. Adjacent cylmdπcal bore 14 there is provided a contour cut-out 22 having a projection 24 and notch 26 which together act as a key for a connector (not shown) for mating with the pms 62 of the initiator 60. The preferable angle A of the sides 24a, 24b of the projection 24 is about 120°, or about 60° from the vertical. Notch 26 preferably is square or rectangular in shape although any suitable shape can be used to provide this keying function It is noted that the construction for the key projection and notch may be varied to cooperate with different types of connectors. Contour cut-out 22 further includes openings 28 on either side of the connector adapter

The openings 28 have surfaces 28a, 28b that extend in directions approximately 60° (angle B) apart, or about 30° from the horizontal. Openings 28 provide positive visual indication that biased tabs on a connector (not shown) properly clip into connector adapter 1, thereby ensuπng proper mechanical and electπcal connection between initiator 60 and a connector Openings 28 also provide a means for depressing a connector's tabs to thereby disconnect the connector from the initiator 60, if so desired.

With reference now to Fig. 8, in use, the connector adapter 1 is seated in an end plate 50 of a pressure vessel 52 of an inflator. The end plate 50 preferably has a coπesponding stepped hole 64 to receive the stepped structure presented by the outer surface of the connector adapter 1.

The pressure vessel 52 preferably is charged with a gas 54 that is used to inflate an air bag. To ensure an air tight seal before and after final assembly, initiator 60 preferably is covered by a sleeve 56, which is secured by, for example, welding, to end plate 50. Preferably, an O-πng 58 is provided for an even better seal. It is noted that the connector adapter need only be dropped into the stepped hole 64 without welding, soldeπng or other type of adhesive means, although such adhesion or other suitable techniques are still contemplated to be within the scope of the instant invention.

In accordance with the present invention the connector adapter 1, via the cy ndπcal bore

14 and frustoconical portion 16, provides physical support for the initiator 60 against the internal storage and operating pressures of the inflator, centers the initiator 60 relative to connector interface features, i.e., contour cut-out 22, and retains the initiator 60 at the correct height and oπentation to receive a connector.

Since the outside surface of connector adapter 1 includes step 20, the initiator 60 is seated properly in stepped hole 64 of the end plate 50, thereby ensuπng the proper positioning, e.g., height, of the initiator 60 and connector adapter 1 for assembly and sealing. Step 20 also supports the connector adapter 1 in end plate 50 against the internal storage and operating pressures of the pressure vessel 52.

The end of the connector adapter 1 opposite the frustoconical portion 16 while being cylmdπcal on the outside has a contour cut-out on the inteπor thereof which is compatible with the geometry of a connector. Accordingly, the connector, when installed, is properly seated to the initiator pins 62 and locked in position as desired More importantly, the instant invention eliminates the necessity of a plastic insert conventionally used to orient the connector. This provides a substantial savings over the conventional assembly. Additionally, the instant invention provides mechanical protection for the initiator pins during shipping and assembly prior to installation of the connector. Thus, fewer initiators are destroyed during shipping and assembly leading to increased savings.

Finally, by using die cast zinc or aluminum materials, EMI/RFI shielding is provided for the initiator 60 prior to installation of the connector Plastic inserts do not provide this type of protection and may be equipped with separate metallic shorting clips to provide the desired protection. The present invention has been descπbed in terms of a preferred embodiment so that an understanding of the present invention can be conveyed. The present invention, however, should not be seen as limited to the particular embodiments descπbed herein. Rather, all modification, variations, or equivalent arrangements that are within the scope of the attached claims are considered to be within the scope of the invention. For example, the instant connector adapter can be used for any suitable through-bulkhead pin-style connection.

Claims

WHAT IS CLAIMED IS: 1 An adapter, compπsmg: an adapter body including a first portion having a first outer diameter and a second portion having a second outer diameter, said adapter body having an inner cavity which includes a frustoconical section, a cylmdπcal section and a contour cut-out section. 2. The adapter of claim 1, wherein a transition between said first and second portions is a step. 3. The adapter of claim 2, wherein said step is about 1 mm in height. 4. The adapter of claim 1, wherein said adapter body is die cast. 5 The adapter of claim 4, wherein said adapter body is comprised of at least one of zinc and aluminum. 6. The adapter of claim 1, wherein said contour cut-out compπses a notch and a projection. 7. The adapter of claim 6, wherein said projection includes two angled surfaces each oriented about 60° with respect to a direction in which said notch is impressed.

1 8. The adapter of claim 1, further comprising at least one opening through said adapter body on a side thereof exposing said contour cut-out section.

1 9. The adapter of claim 8, wherein said at least one opening includes two angled surfaces each oπented about 30° with respect to a direction m which said notch is impressed.

1 10. The adapter of claim 1, wherein said frustoconical section and said cyhndπcal section are shaped to receive an initiator and said contour cut-out section is

3 shaped to receive a connector for connecting to pins associated with said initiator.

1 11. An assembly for a pressure vessel of an inflator, comprising:

2 a base plate having a passage therethrough, said passage having a

3 stepped structure;

4 an initiator,

5 a connector adapter having a stepped structure on an outer surface

6 thereof coπesponding to said stepped structure of said passage of said base plate, said

7 connector adapter being disposed in said passage of said base plate, said connector adapter further having an internal cavity at least a portion of which corresponding to a portion of the exterior surface of said initiator, and said initiator being disposed at least partially in said connector adapter. 12. The assembly of claim 11, further comprising a sleeve coveπng one end of said initiator and secured to said base plate 13 The assembly of claim 12, further comprising an O-πng disposed between said initiator and said sleeve. 14 The assembly of claim 12, wherein said sleeve provides a gas-tight seal against said base plate 15. The assembly of claim 11, wherein said connector adapter is compπsed of at least one of zinc and aluminum. 16 The assembly of claim 11, wherein said connector adapter is die cast. 17 The assembly of claim 11, wherein said inner cavity compπses a frustoconical section, a cylmdπcal section and a contour cut-out section.