Patent Application
20090293752
The present disclosure relates to a header assembly and more particularly to a header assembly for an initiator.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Initiators may be used in a wide range of applications to supply rapid and intense heat to a device. For example, an initiator may be used in conjunction with an inflator of an airbag assembly in initiation of a chemical reaction, in pharmaceutical devices, in initiation of other energetic events such as mining activities, initiation of heating or pressurization, or other chemical reactions in medical devices or diagnostic equipment. When used in conjunction with an inflator, the initiator may selectively ignite a volume of gas disposed within the inflator to fill an airbag of the airbag assembly in response to an impact event experienced by a vehicle. When used in conjunction with certain medical devices, the igniter may selectively supply heat to the substrate to initiate the reaction of an additional chemical composition.
Conventional initiators typically include a pyrotechnic material disposed on a distal end of a header assembly which, when energized, ignites and supplies heat rapidly to an area generally surrounding the pyrotechnic material. While conventional initiators adequately supply heat when the pyrotechnic material is ignited, performance of such initiators may be degraded if the pyrotechnic material is cracked and/or misaligned relative to the header assembly of the initiator. Pyrotechnic material used in conventional initiators may be prone to such cracking and/or misalignment, as such pyrotechnic material is typically disposed on an open, outer surface of the header assembly. Furthermore, because the pyrotechnic material is typically disposed at an open, distal end of the header assembly, the amount of pyrotechnic material employed by the initiator is typically limited and is difficult to apply during manufacturing of the header assembly. Additionally, the primary pyrotechnic material is typically consolidated onto the bridgewire or ignition element. This header/bridgewire subassembly may be inserted directly into the pyrotechnic material to provide the required intimate contact to aid in rapid initiation of additional pyrotechnic output compositions. The method herein described does not require this intimate contact or consolidation.
A header assembly for an initiator may include a first conductive pin, a second conductive pin, and a connector extending between and electrically connected to the first conductive pin and the second conductive pin. A housing may support the first conductive pin, the second conductive pin, and the connector and may include at least one flange extending away from the housing and above the pins. The at least one flange may include at least one opening to facilitate attachment of the connector to the first conductive pin and the second conductive pin.
A header assembly for an initiator may include a first conductive pin, a second conductive pin, and a connector extending between and electrically connected to the first conductive pin and the second conductive pin. A housing may support the first conductive pin, the second conductive pin, and the connector and may include a pair of diametrically disposed flanges extending from a top surface of the housing. The pair of diametrically disposed flanges may define a pair of diametrically disposed openings.
A header assembly for an initiator may include a first conductive pin, a second conductive pin, and a connector extending between and electrically connected to the first conductive pin and the second conductive pin. A housing may support the first conductive pin, the second conductive pin, and the connector. The housing may include at least one opening extending through a sidewall thereof and in communication with the pyrotechnic region.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
With reference to the figures, a header assembly 10 for use in an initiator (not shown) is provided and may include a first conductive pin 12, a second conductive pin 14, a connector 16, and a housing 18. The connector 16 may extend between and may be electrically connected to the first conductive pin 12 and the second conductive pin 14. The housing 18 may support each of the first conductive pin 12, second conductive pin 14, and connector 16 and may facilitate positioning the first conductive pin 12, second conductive pin 14, and connector 16 relative to a pyrotechnic material (not shown) to selectively ignite the pyrotechnic material.
The first conductive pin 12 may be formed of any suitable conductive material and may include a first end 20 and a second end 22. Similarly, the second conductive pin 14 may be formed of any suitable conductive material and may include a first end 24 and a second end 26. The first end 20 of the first conductive pin and the first end 24 of the second conductive pin 14 may extend from the housing 18 for attachment to the connector 16. The second end 22 of the first conductive pin 12 and the second end 26 of the second conductive pin 14 may extend from an opposite end of the housing 18 for connection to a power source 28. The first conductive pin 12 and second conductive pin 14 may include an outer diameter substantially equal to 0.02 inches if used in any initiator having an outer diameter of substantially equal to 0.08 inches. Alternatively, the first conductive pin 12 and second conductive pin 14 may include an outer diameter substantially equal to 0.04 inches if used in any initiator having an outer diameter substantially equal to 0.32 inches.
The connector 16 may be electrically connected to the first end 20 of the first conductive pin 12 and may be electrically connected to the first end 24 of the second conductive pin 14 such that the connector 16 electrically couples the first conductive pin 12 and second conductive pin 14. The connector 16 may be formed from any suitable conductive material that permits electrical communication between the first conductive pin 12 and the second conductive pin 14 when the power source 28 is energized. The connector 16 may be a bridgewire, a semiconductor bridge (SCB), a thin-film bridge, a fiber optic coupled laser firing signal device, or a direct laser diode firing signal device. The connector 16 may include square wire or a wire strip that is bridgewire welded to the first conductive pin 12 and the second conductive pin 14. Attaching the connector 16 to the first conductive pin 12 and the second conductive pin 14 provides an electrical connection between the first conductive pin 12 and the second conductive pin 14, as will be described in greater detail below.
The connector 16 may be attached to at least one of a top surface 30 of the first conductive pin 12 and a side surface 32 of the first conductive pin 12. Similarly, the connector 16 may be attached to at least one of a top surface 34 of the second conductive pin 14 and a side surface 36 of the second conductive pin 14. Regardless of the particular location of attachment, the connector 16 may be welded to the first conductive pin 12 and second conductive pin 14 using any suitable welding process. While a welding process is disclosed, any method of electrically attaching the connector 16 to the conductive pins 12, 14 such as, for example, soldering, brazing, may alternatively or additionally be employed.
The housing 18 may include a main body 38 and a pair of support arms 40 extending from and attached to the main body 38. The main body 38 and support arms 40 may be formed from an insulating material such as, for example, a polymer plastic material. Forming the main body 38 and support arms 40 from a polymer plastic material allows the main body 38 and support arms 40 to be integrally formed during an injection-molding process. Furthermore, forming the main body 38 and support arms 40 from a polymer plastic material allows the main body 38 of the housing 18 to insulate the first conductive pin 12 from the second conductive pin 14 along a length of each of the first conductive pin 12 and the second conductive pin 14. While the housing 18 is described as being formed from a polymer plastic material and via an injection-molding process, the housing 18 could be formed from any insulating material and from any manufacturing process that permits attachment of the support arms 40 to the main body 38 and insulates the first conductive pin 12 from the second conductive pin 14.
The support arms 40 may include any shape and may be positioned at any location along an outer surface 42 of the main body 38. The support arms 40 may be used to attach and hold the main body 38 relative to an external device such as, for example, an inflator of an automotive-airbag system or a substrate of a device to be initiated (i.e., a heating device; neither shown). Because the header assembly 10 may be used in various external devices, the position of the support arms 40 relative to the main body 38 may be dictated by the attachment method of the header assembly 10 to the external device and, therefore, may be positioned at any radial position around the main body 38.
The housing 18 may also include a pair of flanges 44 extending generally from the main body 38. The flanges 44 may be integrally formed with the main body 38 of the housing 18 and may include a chamfer 46 disposed at a distal end thereof. The chamfer 46 may facilitate insertion of the flanges 44 and, thus, the main body 38 into an external device such as, for example, an inflator of an airbag system or a heating device (neither shown).
The flanges 44 may cooperate with a top surface 48 of the main body 38 to define a pocket 50 for receiving pyrotechnic material (not shown) therein. The pyrotechnic material may be inserted into the pocket 50 as a slurry or, alternatively, may be formed as a dry granule and loaded into the pocket 50 during manufacturing of the header assembly 10. Cooperation between the flanges 44 and the top surface 48 of the main body 38 allows for the application of the pyrotechnic material without requiring consolidation steps following application of the pyrotechnic material. For example, because the flanges 44 maintain the pyrotechnic material generally within the pocket 50 and, further, because the pyrotechnic material may bond to a plurality of components (i.e., the first conductive pin 12, the second conductive pin 14, the connector 16, the flanges 44, and the top surface 48 of the main body 38), further consolidation steps to maintain the pyrotechnic material generally at a top portion of the header assembly 10 are generally not required.
The flanges 44 may also cooperate to define at least one opening 52 in communication with the pocket 50. While the housing 18 may include any number of openings 52, the housing 18 will hereinafter be shown in the drawings as including a pair of openings 52 disposed generally between the flanges 44. Furthermore, while the flanges 44 and openings 52 may be positioned at any location around a perimeter of the main body 38, the pair of flanges 44 and pair of openings 52 will hereinafter be shown and described as being diametrically opposed.
As shown in
In addition to providing access to the first conductive pin 12 and second conductive pin 14 during manufacturing of the header assembly 10, the openings 52 also may act as a path for allowing vapor and/or energy to escape the housing 18. For example, when the pyrotechnic material is loaded into the pocket 50, the pyrotechnic material may be loaded as a slurry and, therefore, must cure prior to use of the header assembly 10. Depending on the particular pyrotechnic material used, vapor may be emitted during curing of the pyrotechnic mixture. Such vapor may escape the pocket 50 and, thus, the housing 18, as the wet pyrotechnic material cures via openings 52.
In addition to providing an escape path for vapor emitted from curing pyrotechnic material, the openings 52 may provide direction to energy generated during ignition of the pyrotechnic material. For example, when the power source 28 applies electrical energy to the first conductive pin 12 and the second conductive pin 14, energy is transmitted to the connector 16 and causes ignition of the pyrotechnic material and a subsequent release of heat. The heat caused by ignition of the pyrotechnic material may be dissipated from the pocket 50 via openings 52, which may be located at any position relative to the main body 38 to direct the heat in a desired direction.
The flanges 44 may extend generally above the top surface 48 of the housing 18 and, therefore, may increase the ability of the header assembly 10 in receiving pyrotechnic material. Specifically, the flanges 44 help retain the pyrotechnic material adjacent to the top surface 48 of the main body 38 and, as such, permit a greater volume of pyrotechnic material to be positioned adjacent to the top surface 48 of the main body 38. Positioning a greater volume of pyrotechnic material adjacent to the first conductive pin 12, second conductive pin 14, and connector 16 increases the output of the header assembly 10 and associated initiator. Without the flanges 44, the pyrotechnic material would be deposited on the top surface 48 of the main body 38 and may overflow and run down the outer surface 42 of the main body 38 if excess amounts of pyrotechnic material were placed on the top surface 48.
The openings 52 may include a width that permits a wet slurry of pyrotechnic material to be deposited within the pocket 50 during manufacturing of the header assembly 10 without allowing the wet pyrotechnic material to escape the pocket 50. For example, the openings 52 include a width that restricts flow of wet pyrotechnic material out of the pocket 50 during manufacturing of the header assembly 10 to maximize the amount of pyrotechnic material disposed within the pocket 50. The openings 52 may include a greater width if the pyrotechnic material inserted into the pocket 50 includes a higher viscosity (i.e., is closer to a cured state) when applied.
The pocket 50 may be generally defined between the flanges 44 and the top surface 48 of the main body 38. The pocket 50 may also include a recess 54 that receives the first end 20 of the first conductive pin 12 and the first end 24 of the second conductive pin 14. The recess 54 may extend between the first conductive pin 12 and the second conductive pin 14 such that the connector 16 is generally received within the recess 54. The recess 54 may include a top surface 56 that is recessed from the top surface 48 of the main body 38. The top surface 56 may be positioned in close proximity to a bottom portion of the connector 16 to support the connector 16 during assembly and use of the connector 16. While the top surface 56 of the recess 54 is described as being in close proximity to the connector 16, the top surface 56 of the recess 54 may alternatively be spaced apart from the connector 16 such that a gap is provided between the top surface 56 and the connector 16. If a gap is provided between the top surface 56 and the connector 16, the pyrotechnic material may fill the gap when the pyrotechnic material is installed into the pocket 50.
The first end 20 of the first conductive pin 12 and the first end 24 of the second conductive pin 14 may extend above the top surface 56 of the recess 54 and above the top surface 48 of the main body 38 to expose both the top surface 30 and side surface 32 of the first conductive pin 12 and the top surface 34 and side surface 36 of the second conductive pin 14. Exposing the side surfaces 32, 36 of the conductive pins 12, 14 allows a mold (not shown) that forms the housing 18 to adequately seal the insulating material of the housing 18 against the side surfaces 32, 36 of the conductive pins 12, 14. Allowing engagement of the insulating material of the housing 18 to fully engage an outer perimeter of each of the conductive pins 12, 14 improves the ability of the housing 18 in insulating the first conductive pin 12 from the second conductive pin 14 and also aids in immobilizing the conductive pins 12, 14. Immobilizing the conductive pins 12, 14 prevents relative movement between the conductive pins 12, 14 and the housing 18 and, as such, reduces the likelihood that stresses are applied to a junction between the first conductive pin 12 and the connector 16 and to a junction between the second conductive pin 14 and the connector 16. Reducing the forces applied at junctions of the conductive pins 12, 14 and the connector 16 reduces the likelihood of causing a fracture at either junction and, therefore, reduces the likelihood that electrical communication between the first conductive pin 12 and the second conductive pin 14 via the connector 16 will be lost.
With continued reference to
Ignition of the pyrotechnic material disposed within the pocket 50 causes a rapid burst of heat, which may be used to initiate the external device. For example, the burst of heat supplied by the ignited pyrotechnic material may be used to ignite a chemical gas generant disposed within an inflator of the airbag assembly. Alternatively, the burst of heat may be used to initiate the heating reaction of a chemical composition. In either application, the heat released during ignition of the pyrotechnic material may be used to initiate an external system. While an airbag system and a drug-delivery system are disposed, the header assembly 10 may be used with any ignition system and is not limited as such.
With particular reference to
The header assembly 10a may include a first conductive pin 12, a second conductive pin 14, a connector 16, and a housing 18a. The housing 18a may include a pair of flanges 44a defining a pair of openings 52a. As with the header assembly 10, the number of flanges 44a and number of openings 52a is not limited to a single pair of flanges 44a and a single pair of openings 52a.
The flanges 44a may be disposed on opposite sides of the main body 38a such that the flanges 44a are diametrically opposed. Similarly, the openings 52a may be disposed on opposite sides of the main body 38a such that the openings 52a are diametrically disposed. The openings 52a may extend from a top surface 48 of the main body 38a to a distal end of each flange 44a. A bottom portion of each opening 52a may include an arcuate surface 62 that aids in directing vapor and/or heat from a pocket 50a defined generally by the flanges 44a and openings 52a.
The flanges 44a may each include an aperture 64 extending therethrough. The aperture 64 may include any shape and may be disposed at any location on the respective flange 44a. For example, the aperture 64 may include a generally rectangular shape, as shown in
With particular reference to
The header assembly 10b may include a first conductive pin 12, a second conductive pin 14, a connector 16, and a housing 18b. The housing 18b may include a main body 38b and a pair of flanges 44b extending therefrom, which may cooperate to define a pair of openings 52b. A ring 68 may be disposed at a distal end of each flange 44b and may extend across each opening 52b. The ring 68 may cooperate with each flange 44b to define the shape of each opening 52b. The openings 52b may include a size that is large enough to permit access to each conductive pin 12, 14 to allow attachment of the connector 16 to each of the conductive pins 12, 14. The ring 68 may be fixedly attached at the distal end of each flange 44b to strengthen the flanges 44b and prevent damage to the housing 18b when installed into an external device and during ignition of the pyrotechnic material.
As with the header assembly 10 and header assembly 10a, the openings 52b may also be used to allow vapor to escape from the pocket 50b when the pyrotechnic material disposed therein cures and to direct heat from the ignited pyrotechnic material. Therefore, the openings 52b may be positioned at any location around the main body 38b provided the openings 52b extend through the flanges 44b and communicate with the pocket 50b.
With particular reference to
The header assembly 10c may include a first conductive pin 12, a second conductive pin 14, a connector 16c, and a housing 18c. The housing 18c may include a pair of openings 52c that are formed into a main body 38c of the housing 18c. The openings 52c may extend generally from an outer surface 42 of the main body 38c and may be in communication with a pocket 50c.
The pocket 50c may receive a pyrotechnic material disposed therein, whereby the pyrotechnic material generally surrounds the connector 16c and conductive pins 12, 14. Because material is removed from the main body 38c to form the openings 52c, more pyrotechnic material may be inserted into the pocket 50c and retained therein within the openings 52c.
In addition to allowing use of a greater volume of pyrotechnic material, the openings 52c may also allow vapor and/or heat to escape the housing 18c. As described above, when the pyrotechnic material cures, vapor may be released. The openings 52c may provide a path by which vapor escapes the housing 18c. Also, when the pyrotechnic material is ignited by the connector 16c, the heat generated due to ignition of the pyrotechnic material may be directed away from the housing 18c via the openings 52c.
While the header assembly 10 is the only assembly shown in conjunction with a power source 28, a sensor 58, and a controller 60, each of the header assemblies 10a, 10b, and 10c may similarly be in communication with a power source 28, a sensor 58, and a controller 60. Furthermore, each of the header assemblies 10, 10a, 10b, and 10c may be used in conjunction with any external system that requires heat as an ignition source. For example, as described above with regard to the header assembly 10, each of the header assemblies 10, 10a, 10b, and 10c may be used to initiate firing of an airbag system or to initiate the heating reaction of a chemical composition or other reaction initiation such as initiation of reaction that requires a local increase in energy to then propagate on its own.
With particular reference to
The director 70 may include a main body 72, a first bore 74, and a second bore 78. The first bore 74 may extend generally through the main body 72. The second bore 78a may be in communication with the first bore 74 and may extend at least partially along a length of the main body 72 for receiving the main body 38 of the housing 18. The first bore 74 may include an inner surface 76 in fluid communication with a top portion of the header assembly 10. Providing the inner surface 76 of the first bore 74 in communication with the top portion of the header assembly 10 allows the inner surface 76 of the first bore 74 to generally oppose the pyrotechnic material disposed within the pocket 50 of the header assembly 10.
With continued reference to
With particular reference to
The director 70a may include a main body 72a, a first bore 74a, and a second bore 78a. As with director 70, the first bore 74a may extend generally through the main body 72a while the second bore 78a extends at least partially along a length of the main body 72a and is in fluid communication with the first bore 74a. The first bore 74a may include an inner surface 76a, that cooperates with the header assembly 10 to direct energy in a predetermined direction.
The second bore 78a may receive the main body 38 of the housing 18 to attach the director 70a to the header assembly 10. As such, a top portion of the header assembly 10 may extend into the first bore 74a such that the top portion of the header assembly 10 generally opposes the inner surface 76a of the first bore 74a. While the director 70a is shown as including a second bore 78a that extends substantially through the main body 72a, the second bore 78a may be at least partially closed by the main body 72a such that the main body 72a defines a cavity, whereby the main body 38 of the housing 18 is surrounded by the main body 72a at the second bore 78a.
With continued reference to
As with the director 70 and header assembly 10 described above, positioning the director 70a relative to the header assembly 10 generally guides the heat and energy released due to the ignition of the pyrotechnic material. If, for example, the director 70a and header assembly 10 are installed in an igniter for an automobile air bag system, the first bore 74a may be positioned relative to an inflator of the automotive air bag system such that the inner surface 76a of the first bore 74a directs the heat and energy released due to the ignition of the pyrotechnic material generally toward an inflator the automotive air bag system. Directing the heat and energy released from the pyrotechnic material generally toward the inflator causes the inflator to rapidly fill an air bag of the automotive air bag system.
While specific examples have been described in the specification and illustrated in the drawings, it will be understood by those skilled in the art that various changes may be made and equivalence may be substituted for elements thereof without departing from the scope of the present teachings as defined in the claims. Furthermore, the mixing and matching of features, elements and/or functions between various examples may be expressly contemplated herein so that one skilled in the art would appreciate from the present teachings that features, elements and/or functions of one example may be incorporated into another example as appropriate, unless described otherwise above. Moreover, many modifications may be made to adapt a particular situation or material to the present teachings without departing from the essential scope thereof. Therefore, it may be intended that the present teachings not be limited to the particular examples illustrated by the drawings and described in the specification as the best mode of presently contemplated for carrying out the present teachings but that the scope of the present disclosure will include any embodiments following within the foregoing description and any appended claims.
