Patent Application
20120267882
The embodiments disclosed herein relate generally to improving the time in which side airbags deploy in vehicles, and more particularly to a layout guideline of the components of a vehicle body that contribute to the improvement of the time in which a side airbag deploys.
By law, all new vehicle models must pass certain safety tests before they are sold to the public. However, these safety tests typically provide a minimum statutory standard of safety for new vehicles. Many independent safety assessment programs have been developed, such as the New Car Assessment Program (NCAP), which provide a higher standard of safety for new vehicles. These programs assign safety ratings to new vehicles that describe how well the vehicles performed in various safety tests which include side impact collisions at a fixed velocity (e.g., 32 km/h for oblique pole collisions). Safety ratings are awarded to vehicles based on the level of injury an occupant of the vehicle would have sustained in the collisions performed during the tests.
The use of inflatable airbags stored in various locations of the vehicles such as in the steering wheel, dashboard, seats, or doors have substantially reduced the level of injury inflicted on occupants of the vehicles during a collision. To further reduce the level of injury during collisions, vehicle manufacturers constantly strive to improve the time needed to deploy airbags in their vehicles. The time of deployment describes the time period between the moment of initial impact during a collision and when the airbag deploys. A fast deployment time is desired in order to prevent an occupant from colliding with the interior of the vehicle such as the door.
Airbag restraint systems typically include an impact sensor which triggers deployment of the airbag. For example, for side airbag systems, many vehicle manufacturers use door pressure sensors. Door pressure sensors are effective for early detection of a side impact collision. However, these pressure sensors are expensive. Due to their lower cost, vehicle manufactures use accelerometers or G-sensors as an alternative to pressure sensors to detect side impact collisions. An issue with G-sensor based side impact sensors is that the initial side impact signal received at the sensors during a side impact collision tests is not strong enough to trigger the deployment of the side airbag. In other words, G-sensor based side impact sensors result in a later time of deployment of the side airbag.
Referring now to
In alternative configurations, rather than having the door beam 101A span horizontally across the door, the angle of the door beam is changed as shown by door beam 101B. The door beam 101B is positioned such that one end of the door beam 101B is pointed in the downward (angled) position and is located in close proximity to the side impact sensor 103. Additionally, a bracket 105 is added to stiffen the door beam 101B as illustrated in
Embodiments herein describe a fundamental layout between the inner panel of a door, side sill reinforcement, and uncrushable items within the door of the vehicle. The position of these components with respect to one another dictates whether a side airbag in the vehicle can be quickly deployed during a side impact collision. During a side impact collision, an early time of deployment is desirable in order to allow the side airbag to fully expand before an occupant of the vehicle collides with the side airbag. Full expansion of the side airbag minimizes the risk of injury during a side impact collision.
The features and advantages described in the specification are not all inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter.
The figures depict various embodiments for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles described herein.
A preferred embodiment is now described with reference to the figures where like reference numbers indicate identical or functionally similar elements. Also in the figures, the left most digits of each reference number corresponds to the figure in which the reference number is first used.
Reference in the specification to “one embodiment” or to “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” or “an embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
Certain aspects disclosed herein include process steps and instructions described herein in the form of an algorithm. It should be noted that the process steps and instructions herein could be embodied in software, firmware or hardware, and when embodied in software, could be downloaded to reside on and be operated from different platforms used by a variety of operating systems. The process steps and instructions can also be in a computer program product which can be executed on a computing system.
The disclosure also relates to an apparatus for performing the operations herein. This apparatus may be specially constructed for the purposes, e.g., a specific computer, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a non-transitory computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, application specific integrated circuits (ASICs), or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus. Memory can include any of the above and/or other devices that can store information/data/programs. Furthermore, the computers referred to in the specification may include a single processor or may be architectures employing multiple processor designs for increased computing capability.
The algorithms and displays presented herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may also be used with programs in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform the method steps. The structure for a variety of these systems will appear from the description below. In addition, the disclosure is not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings as described herein, and any references below to specific languages are provided for disclosure of enablement and best mode.
In addition, the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter. Accordingly, the disclosure herein is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the claims.
In the following description, a fundamental layout between the inner panel of a door, side sill reinforcement, and the uncrushable items within the door of a vehicle is described. The layout of the inner panel, side sill reinforcement, and the uncrushable items in relation to each other dictates whether an early time to fire of a side airbag during a side impact collision can be achieved. In one embodiment, the time to fire or the time of deployment describes the interval of time from the initial side impact collision to the deployment of the side airbag. The layout described herein may be applied to any vehicle to achieve an initial side impact signal that results in an early time to fire of an airbag.
Referring now to
Generally, a minimum horizontal distance (e.g., 80 mm) is needed to fully deploy the side airbag 209. To minimize the amount of trauma during a side impact collision, the side airbag 209 should be fully deployed before the occupant 201 comes into contact with the side airbag 209. This allows the occupant 201 to fully utilize the entire stroke of the side airbag 209. During a side impact collision test at 32 km/h as defined by NCAP (other velocities may be defined in future assessment programs), development tests indicate that the side airbag 209 must be deployed by some time threshold (e.g., 7.5 ms) after movement of the door 205 towards the occupant 201 in order to minimize injury to the occupant 201. By deploying the side airbag 209 by the time threshold after the side impact collision, the side airbag 209 can utilize its full expansion stroke thereby providing enough cushion to protect the occupant 201 from injury.
Referring now to
In particular,
Additionally, the space between the inner door panel 303 and the door skin 301 includes uncrushable items 305. In one embodiment, the uncrushable items 305 are items located within the door that are resistant to being crushed during a collision. The uncrushable items 305 are represented by a square in
The side sill is part of the side structure of the vehicle that is coupled to the pillars of the vehicle. The side sill comprises a side sill outer panel 307, side sill reinforcement 309, and side sill inner 311. The side sill outer panel 307, side sill reinforcement 309, and side sill inner 311 are coupled to one another at flanges 315 via various means such as welding, hemming, press fit, or using fasteners such as rivets or a nut(s) and bolt(s).
During a side impact collision, the side sill reinforcement 309 transfers the force of the collision through the side sill inner 311 (and/or through the vehicle body) and into the side impact sensor. Using the side sill reinforcement 309 to transfer the force of the collision causes the sensor to trigger the deployment of the side airbag sensor within the required or threshold amount of time from the initial movement of the inner door panel 303 due to the collision. In order to effectively use the side sill reinforcement 309 to transfer the force of the collision to the sensor, the inner door panel 303, uncrushable items 305, and side sill reinforcement 309 are strategically arranged in a fundamental layout that results in a foreign object (e.g., a pole) coming into contact with the side sill reinforcement 307. The contact between the object and side sill reinforcement 309 results in a G-build up at the side impact sensor which triggers the deployment of the side airbag within the required amount of time.
In one embodiment, the fundamental layout between the inner door panel 303, uncrushable items 305, and side sill reinforcement 309 is characterized by the following relationship:
UI−(InnrPanel to RNFCT)≦25 mm
In the above relationship, the horizontal width of the uncrushable items (UI) minus the distance 313 from the inner door panel 303 (InnrPanel) to a vertical support 317 of the side sill reinforcement 309 (RNFCT) must be less than or equal to 25 mm. In another embodiment, the difference must be less than or equal to 30 mm. In an alternative embodiment, the different must be less than or equal to 20 mm. By minimizing the horizontal space between these components of the vehicle, the contact between the side sill reinforcement 309 and the foreign object causes a G-ramp (i.e., fast rate of acceleration) at the side impact sensor which triggers the deployment of the side airbag within the required time (i.e., within a time threshold).
Referring now to
In
Note that
In one embodiment, to improve the transfer of force from the collision of the pole 400 and the side sill reinforcement 309, a fundamental relationship also exists between the offset or overlap of the side sill reinforcement 309 and the side sill inner 311. As previously mentioned, the force of the impact with the pole 400 is transferred from the side sill reinforcement 309 to the side sill inner 311 before being transferred to the side impact sensor. The relationship of the offset of the side sill reinforcement 309 and the side sill inner 311 allows for the collision G-signal to be transferred to the side impact sensor before the side sill reinforcement 309 is deformed as a result of the collision.
Referring now to
The vertical offset 501 between the top horizontal edge 503 of the side sill inner 311 and the top horizontal edge 505 of the side sill reinforcement 309 is minimized to a threshold distance. In one embodiment, the vertical offset 501 is less than or equal to 3 mm. Similarly, the vertical offset 507 between the bottom horizontal edge 509 of the side sill inner 311 and the bottom horizontal edge 511 of the side sill reinforcement 309 is minimized to a threshold distance. In one embodiment, the vertical offset 507 is less than or equal to 8 mm. Note that in other embodiments, other vertical offsets may be used other than those described herein in order to prevent deformation of the side sill reinforcement 309 during a side impact collision before the G-signal is transferred to the side impact sensor.
Referring now to
Referring now to
Referring now to
In one embodiment, the side impact sensor 801 is located on the B-pillar of the vehicle 800. However, the side impact sensor 801 may be located at different locations on the vehicle 801. As described previously, the side impact sensor 801 is a G-based sensor (accelerometer) that measures the acceleration due to a side impact collision causing the side airbag system 803 to deploy the side airbag. When a threshold acceleration is reached, the side impact sensor communicates the measured acceleration with the processor 805.
In one embodiment, the processor 805 processes data signals such as the side airbag signal and may comprise various computing architectures including a complex instruction set computer (CISC) architecture, a reduced instruction set computer (RISC) architecture, or an architecture implementing a combination of instruction sets. Although only a single processor is shown in
In one embodiment, the memory 807 stores instructions and/or data that may be executed by processor 805. The instructions and/or data may comprise code (i.e., modules) for performing any and/or all of the techniques described herein such as causing the side airbag system 803 to deploy responsive to the side airbag signal received by the processor 805. Memory 807 may be any non-transitory computer-readable storage medium such as dynamic random access memory (DRAM) device, a static random access memory (SRAM) device, Flash RAM (non-volatile storage), combinations of the above, or some other memory device known in the art.
While particular embodiments and applications have been illustrated and described herein, it is to be understood that the disclosure is not limited to the precise construction and components disclosed herein and that various modifications, changes, and variations may be made in the arrangement, operation, and details of the methods and apparatuses of the present invention without departing from the spirit and scope of the invention as it is defined in the appended claims.
