AIRBAG ARRANGEMENT INCLUDING A RECESSED AREA UNDER THE STEERING COLUMN

Abstract

Airbag arrangement (10), comprising: an airbag (14) defining an inflation chamber (18), and an inflation device (16) communicating with the inflation chamber (18), wherein the airbag (14) has a top side (20) and a front side (22) and a back side (24) each extending from the top side (20), the inflation chamber (18) being defined between the front side (22) and the back side (24), wherein the front (22) and the back (24) define two extensions (26) spaced apart along the top (20) and a recess (28) disposed between the extensions (26) along the top (20), wherein the airbag (14) has a depressed area (30) extending from the recess (28), the front (22) and the back (24) being sewn together along the depressed area (30), a seam (40) being configured to maintain the depressed area (30) in the deflated state when the airbag (14) is in the inflated position, or the seam (40) being configured to restrict inflation of the depressed area (30) to keep the depressed area (30) depressed with respect to the extensions (26) when the airbag (14) is in the inflated position, wherein the airbag (14) has a bottom surface (46) spaced from the top surface (20), the front surface (22) and the back surface (24) each extending from the bottom surface (46), the depressed region (30) extending from the top surface (20) towards the bottom surface (46).

Description

BACKGROUND

[0001] Vehicles may incorporate various airbags that deploy during vehicle impact to absorb energy from the vehicle's occupants during the collision. The airbag defines an inflation chamber, and an inflator communicates with the inflation chamber to inflate the airbag from a deflated position to an inflated position. One type of airbag is a knee airbag, which deploys beneath a vehicle's steering column to absorb impact to a driver's knees during a vehicle collision. The knee airbag may be supported by the instrument panel, for example, behind a knee bolster, or by the steering column.

[0002] Vehicles are subjected to various impact tests. These impact tests may include those for which standards have been developed by the IIHS (Insurance Institute for Highway Safety) and the NHTSA (National Highway Traffic and Safety Agency). These impact tests may include tests that urge vehicle occupants to move forward and sideways, offset frontal impacts, and oblique impact tests. One such test is the SORB (small overlap rigid barrier) test, in which a front corner of the vehicle impacts a rigid barrier that is offset from the vehicle's centerline. In this test, the test dummy in the driver's seat is urged forward and toward the impact corner of the vehicle.Another type of impact test is an oblique impact test, in which the vehicle impacts at an angle to the vehicle's centerline and the test dummy in the driver's seat is forced forward and in a transverse direction to the vehicle toward the driver's door of the vehicle or the passenger's door of the vehicle.

[0003] During a collision in which the occupant is forced forward and sideways, the occupant's knees may be forced to slide over the knee airbag toward a forward corner of the vehicle. This sliding movement reduces the absorption of the impact force, and the occupant's knees may slide away from the airbag and impact other components of the vehicle interior. Due to the inflation of the airbag to a relatively high inflation pressure, the occupant's knees may tend to slide in these types of collisions. Depending on various factors, the knee airbag may also balloon around the steering column, which may cause the occupant's knees to slide in collisions in which the occupant is forced to move forward and sideways.

[0004] US 8 376 396 B2 discloses a multi-chamber knee airbag. CN 1 04 742 849 A discloses a safety airbag device for knees. JP 2003 - 226 218 A discloses an occupant protection device with a knee bag that extends in front of a leg portion of a vehicle occupant. US 7 604 252 B2 discloses a driver knee airbag.

[0005] There remains an opportunity to design a knee airbag that reduces the likelihood of the occupant's knees sliding over the knee airbag during impacts that force the occupant to move forward and sideways. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of a dashboard and a steering column of a vehicle, with an exterior of the vehicle shown in phantom. Fig. 2 is a perspective view of an instrument panel with an airbag in an inflated position and an occupant being displaced leftward in the vehicle in response to a vehicle impact. Fig. 3 is a perspective view of an instrument panel with an airbag in an inflated position and an occupant being displaced to the right front of the vehicle in response to a vehicle impact. Fig. 4 is a perspective view of the airbag. Fig. 5 is a cross-sectional view of the airbag taken along line 5 in Fig. 4. Fig. 6 is a cross-sectional view of the airbag taken along line 6 in Fig. 4. Fig. 7 is a schematic diagram of an airbag system. DETAILED DESCRIPTION

[0006] Referring to the figures, wherein like reference numerals designate like parts throughout the several views, an airbag assembly 10 for a vehicle 12 includes an airbag 14 and an inflator 16. The airbag 14 defines an inflation chamber 18, and the inflator 16 communicates with the inflation chamber 18. The airbag 14 has a top surface 20 and a front surface 22 and a back surface 24 each extending from the top surface 20. The inflation chamber 18 is defined between the front surface 22 and the back surface 24. The front surface 22 and the back surface 24 define two extensions 26 spaced apart along the top surface 20 and a recess 28 disposed between the extensions 26 along the top surface 20. The airbag 14 includes a depressed area 30 extending from the recess 28. The front side 22 and the back side 24 are connected to each other along the recessed area 30.

[0007] Because the recess 28 is disposed between the extensions 26 along the top surface 20, the extensions 26 and the recess 28 can wrap around a steering column 32 of the vehicle 12, as explained further below. This configuration reduces the likelihood of the airbag 14 ballooning around the steering column 32. Furthermore, because the front surface 22 and the rear surface 24 are connected along the recessed area 30, the recessed area 30 also reduces the likelihood of the airbag 14 ballooning around the steering column 32.

[0008] When designing the airbag assembly 10, the size of the recessed area 30 can be adjusted to adjust the inflation pressure in the inflation chamber 18 without adjusting the size of the inflator 16 and / or without adding and / or modifying vents in the airbag 14. Adjusting the size of the recessed area 30 to adjust the inflation pressure may be simpler and less expensive than adjusting the size of the inflator 16. For example, the inflation pressure may be adjusted by adjusting the size of the recessed area 30 when an airbag assembly 10 is redesigned from one model year to the next, when the airbag assembly 10 is redesigned from one vehicle model to another vehicle model, etc.

[0009] With reference to the Fig. 1-3, the airbag 14 may be a knee airbag. Specifically, a steering column assembly 34 may include the steering column 32 and the airbag 14, and the airbag 14 may be deployable beneath the steering column 32 to absorb the impact of a driver's knees upon impact of a vehicle 12. In this configuration, the airbag 14 may be supported by an instrument panel 36, for example, behind a knee bolster 44, and / or by the steering column 32.

[0010] The airbag 14 can be deployed from a non-inflated position (see Fig. 1) to an inflated position (see Fig. 2 and Fig. 3) be inflatable. In the deflated position, the airbag 14 may be stowed behind a panel, such as the knee bolster 44 and / or a bezel on the steering column 32. The inflator 16 may inflate the inflation chamber 18 to inflate the airbag 14 to the inflated position, in which the airbag 14 extends through the panel to absorb the energy impact from the driver's knees during a collision of the vehicle 12.

[0011] With reference to Fig. 2 and Fig. 3, the extensions 26 and the recess 28 are configured to extend partially around the steering column 32 when the airbag 14 is in an inflated position. According to Fig. 2 and Fig. 3, the extensions 26 and the recess 28 are U-shaped. The recess 28 and the extensions 26 can each be configured to extend along the steering column 32 of a vehicle 12. The recessed area 30 is configured to be located below the steering column 32 in the inflated position, and the extensions 26 are configured to extend upward along sides of the steering column 32 in the inflated position. The extensions 26 and the recess 28 can be configured to abut the steering column 32 in the inflated position, according to the embodiment shown.

[0012] With reference to Fig. 4-6, as set forth above, the recess 28 and the extensions 26 extend along the top surface 20 of the airbag 14. The airbag 14 has a bottom surface 46 spaced from the top surface 20. In the inflated position, the top surface 20 is disposed on an upper side of the airbag 14, and the bottom surface 46 is disposed on a lower side of the airbag 14. The front surface 22 and the back surface 24 may each extend from the top surface 20 to the bottom surface 46.

[0013] With further reference to Fig. 4-6, the front side 22 and the back side 24 may each extend from the top side 20 to the bottom side 46 along a left side 58 and a right side 60. The extensions 26 may be defined on the left side 58 and the right side 60. The top side 20, the bottom side 46, the left side 58, and the right side 60 may be integral with each other, i.e., simultaneously as a single unit, or they may be stitched panels.

[0014] When the airbag 14 is in the inflated position, the distance between the front 22 and the back 24 at the extensions 26 is greater than the distance between the front 22 and the back 24 at the depressed area 30. In other words, the airbag 14 is thicker at the extensions 26 than at the depressed area 30. The depressed area 30 may not be inflated when the airbag 14 is in the inflated position, or, alternatively, inflation may be restricted such that the depressed area 30 is depressed with respect to the extensions 26.

[0015] The airbag 14 may include a main portion 38 formed by the front side 22 and the rear side 24 below the extensions 26 and the recessed area 30. The distance between the front side 22 and the rear side 24 at the main portion 38 is greater than the distance between the front side 22 and the rear side 24 at the recessed area 30. In other words, the airbag 14 is thicker at the main portion 38 than at the recessed area 30.

[0016] According to the invention, the front side 22 and the back side 24 are sewn together along the depressed area 30. More specifically, the front side 22 and the back side 24 can be engaged by the seam 40. According to the invention, the seam 40 is configured, for example, sized and shaped, such that the depressed area 30 remains in the deflated state when the airbag 14 is in the inflated position, or, as an alternative according to the invention, the seam 40 is configured to restrict inflation of the depressed area 30 to keep the depressed area 30 depressed with respect to the extensions 26 when the airbag 14 is in the inflated position.

[0017] The seam 40 may extend around the perimeter of the recessed area 30 to define the boundary of the recessed area 30. The seam 40 may extend across the recessed area 30 to at least partially reinforce the recessed area 30 to keep the recessed area 30 recessed relative to the extensions 26 and the main portion 38 when the airbag 14 is in the inflated position.

[0018] Alternatively, or in addition to the seam 40, relative movement of the front side 22 and the back side 24 in the recessed area 30 may be restricted in any suitable manner. For example, the front side 22 and the back side 24 may be welded, fused, glued, etc., together at the recessed area 30.

[0019] According to the invention, the recessed region 30 extends from the top side 20 toward the bottom side 46. In other words, the recessed region 30 begins at the top side 20, extends to the bottom side 46, and can end before the bottom side 46, ie, can be spaced from the bottom side 46. The recessed region 30 can extend 10-70 mm from the top side 20 toward the bottom side 46.

[0020] The recessed region 30 may be disposed between the extensions 26. Specifically, the recessed region 30 may extend from one extension 26 to the other extension 26, ie, may terminate at the extensions 26. In the illustrated embodiment, the recessed region 30 is generally rectangular from the top surface 20 toward the bottom surface 46 and between the extensions 26.

[0021] The main portion 38 of the airbag 14 may have regions of different thickness, ie, a distance between the front 22 and the back 24, when the airbag 14 is in the inflated position. As shown in Fig. For example, as shown in Figures 4-6, the main portion 38 may define a pocket 42 disposed beneath the depressed area 30 and a cushion 44 extending around the pocket 42 when the airbag 14 is in the inflated position, i.e., between the pocket 42 and the bottom surface 46. The pocket 42 and the cushion 44 may be formed in any suitable manner when the airbag 14 is in the inflated position. For example, tethers and / or internal vents may define the pocket 42 and the cushion 44.

[0022] For example, the pocket 42 and the cushion 44 can accommodate the occupant's knees when the airbag 14 is in the inflated position during a collision of the vehicle 12. In this position, the pocket 42 and the cushion 44 can limit or prevent movement of the occupant's knees in a transverse direction of the vehicle 12 toward a driver's door or a passenger door of the vehicle 12. Specifically, the pocket 42 and the cushion 44 can limit or prevent the occupant's knees from sliding over the airbag 14.

[0023] The airbag 14 may be formed from any suitable type of material, such as a polymer fabric. For example, the airbag 14 may be formed from a nylon yarn fabric, such as nylon 6.6. Other suitable examples include polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyester, or any other suitable polymer. The polymer fabric may include a coating such as silicone, neoprene, urethane, etc. For example, the coating may be polyorganosiloxane.

[0024] As explained above, the airbag arrangement 10 has the schematically shown in Fig. 7. The inflator 16 communicates with the inflation chamber 18 to expand the inflation chamber 18 with an inflation medium, such as a gas. The inflator 16 may, for example, be a pyrotechnic inflator 16, in which a chemical reaction is used to propel the inflation medium to the inflation chamber 18. The inflator 16 may be of any suitable type, for example, a cold gas inflator 16.

[0025] The airbag assembly 10 may be mounted to the vehicle 12 in any suitable manner. For example, the airbag assembly 10 may be mounted to the instrument panel 36 and / or the steering column 32.

[0026] The airbag assembly 10 may be a component of an airbag system 48, which is shown schematically in Fig. 7. The airbag system 48 includes an impact sensing system 50 having at least one impact sensor 52 for sensing the impact of the vehicle 12. The impact sensor 52 is the only component of the impact sensing system 50 that is Fig. 7; however, it is understood that the impact sensing system 50 may include additional components not shown in Fig. 7 are shown.

[0027] The airbag assembly 10 may include a controller 54. The controller 54 and the sensor 52 may be connected to a communication bus 56, such as a CAN bus (Controller Area Network), of the vehicle 12. The controller may use information from the communication bus 56 to control the deployment of the inflator 16. The inflator 16 may be connected to the controller 54 as shown in Fig. 7, or may be connected directly to the communication bus 56.

[0028] The controller 54 may communicate directly or through the communication bus 56 with the sensor 52 and the inflator 16 to activate the inflator 16, for example, to provide a pulse to a pyrotechnic charge of the inflator 16 when the sensor 52 detects an impact of the vehicle 12. Alternatively, or in addition to detecting the impact, the impact detection system 50 may be configured to detect impacts prior to impact, i.e., for pre-impact detection. The sensor 52 may be of any suitable type, for example, using radar, lidar, and / or a vision system. The vision system may include one or more cameras, CCD image sensors and / or CMOS image sensors 52, etc.

[0029] Controller 54 may be a microprocessor-based controller. Sensor 52 communicates with controller 54 to communicate data to the controller. Based on the data communicated by sensor 52, the controller commands activation of inflator 16.

[0030] The disclosure has been described in an illustrative manner, and it is understood that the terminology used is intended to be in the nature of description rather than limitation. Many modifications and variations of the present disclosure are possible in light of the above teachings, and the disclosure may be practiced otherwise than as specifically described.

Claims

[1] Airbag arrangement (10), comprising: an airbag (14) defining an inflation chamber (18), and an inflation device (16) communicating with the inflation chamber (18), wherein the airbag (14) has a top side (20) and a front side (22) and a back side (24) each extending from the top side (20), the inflation chamber (18) being defined between the front side (22) and the back side (24), wherein the front (22) and the back (24) define two extensions (26) spaced apart along the top (20) and a recess (28) disposed between the extensions (26) along the top (20), wherein the airbag (14) has a depressed area (30) extending from the recess (28), the front (22) and the back (24) being sewn together along the depressed area (30), a seam (40) being configured to maintain the depressed area (30) in the deflated state when the airbag (14) is in the inflated position, or the seam (40) being configured to restrict inflation of the depressed area (30) to keep the depressed area (30) depressed with respect to the extensions (26) when the airbag (14) is in the inflated position, wherein the airbag (14) has a bottom surface (46) spaced from the top surface (20), the front surface (22) and the back surface (24) each extending from the bottom surface (46), the depressed region (30) extending from the top surface (20) towards the bottom surface (46). [2] The airbag assembly (10) of claim 1, wherein the extensions (26) and the recess (28) are U-shaped and wherein the recessed portion (30) is rectangular. [3] The airbag assembly (10) of claim 2, wherein the recessed portion (30) extends from one of the extensions (26) to the other extension (26). [4] Airbag arrangement (10) according to one or more of the preceding claims, wherein the recessed region (30) extends 10 - 70 mm from the upper side (20) towards the lower side (46). [5] The airbag assembly (10) of claim 1, wherein the airbag (14) is inflatable from a non-inflated position to an inflated position, wherein the distance between the front (22) and the rear (24) at the extensions (26) is greater than the distance between the front (22) and the rear (24) at the depressed area (30). [6] The airbag assembly (10) of claim 1, wherein the recess (28) is configured to extend along a steering column (32) of a vehicle (12). [7] Steering column assembly (34) comprising: a steering column (32) and an airbag (14) having two extensions (26) and a recess (28) arranged between the extensions (26), the extensions (26) and the recess (28) being configured to extend partially around the steering column (32) when the airbag (14) is in an inflated position, wherein a front side (22) and a back side (24) of the airbag (14) are sewn together along a recessed area (30) configured to be located below the steering column (32) in the inflated position, wherein a seam (40) is configured to maintain the recessed area (30) in the deflated state when the airbag (14) is in the inflated position, or the seam (40) is configured to restrict inflation of the recessed area (30) to keep the recessed area (30) recessed with respect to the extensions (26) when the airbag (14) is in the inflated position, and wherein the distance between the front (22) and the back (24) on the extensions (26) is greater than the distance between the front (22) and the back (24) on the recessed area (30), wherein the airbag (14) has a top side (20) and a bottom side (46), wherein the front side (22) and the back side (24) each extend from the top side (20) to the bottom side (46), wherein the depressed area (30) extends from the top side (20) towards the bottom side (46). [8] Steering column assembly (34) according to claim 7, wherein the extensions (26) and the recess (28) are U-shaped and wherein the recessed area (30) is rectangular. [9] Steering column assembly (34) according to claim 8, wherein the recessed portion (30) extends from one of the extensions (26) to the other extension (26). [10] Steering column assembly (34) according to one or more of claims 7 to 9, wherein the recessed region (30) extends 10 - 70 mm from the top side (20) towards the bottom side (46). [11] The steering column assembly (34) of claim 7, wherein the extensions (26) and the recess (28) are configured to abut the steering column (32) in the inflated position. [12] Steering column assembly (34) comprising: a steering column (32) and an airbag (14) having two extensions (26) and a recess (28) arranged between the extensions (26), the extensions (26) and the recess (28) being configured to extend partially around the steering column (32) when the airbag (14) is in an inflated position, wherein a front side (22) and a back side (24) of the airbag (14) are sewn together along a recessed area (30) configured to be located below the steering column (32) in the inflated position, wherein a seam (40) is configured to maintain the recessed area (30) in the deflated state when the airbag (14) is in the inflated position, or the seam (40) is configured to restrict inflation of the recessed area (30) to keep the recessed area (30) recessed relative to the extensions (26) when the airbag (14) is in the inflated position, and wherein the airbag (14) has a top side (20) and a bottom side (46), wherein the front side (22) and the back side (24) each extend from the top side (20) to the bottom side (46), wherein the depressed area (30) extends from the top side (20) towards the bottom side (46).

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