Patent Publication Number: US-2007102907-A1

Title: Inflatable curtains with gas generating cord inflators

Description:
FIELD OF THE INVENTION  
      The present invention relates to an inflatable vehicle occupant protection device for helping to protect an occupant of a vehicle.  
     BACKGROUND OF THE INVENTION  
      It is known to inflate an inflatable vehicle occupant protection device to help protect a vehicle occupant in the event of a vehicle collision. Examples of inflatable vehicle occupant protection devices include driver and passenger frontal air bags, side air bags, inflatable curtains, inflatable seat belts, inflatable knee bolsters, and inflatable head liners.  
      An inflatable curtain is inflatable away from the roof of the vehicle to a position between a side structure of the vehicle and occupants of vehicle seating. Typically, an inflation fluid source, such as a stored gas inflator, heated gas inflator, pyrotechnic inflator, hybrid inflator, or augmented inflator, is located externally of the inflatable curtain. In this instance, a conduit, such as a fill tube, delivers inflation fluid from the inflation fluid source to the inflatable curtain.  
     SUMMARY OF THE INVENTION  
      The present invention relates to an apparatus for helping to protect an occupant of a vehicle that has a side structure, a first row seat, and a second row seat. The apparatus includes a first inflatable curtain inflatable between the side structure and an occupant of the first row seat. A first gas generating cord generates inflation fluid for inflating the first inflatable curtain. The apparatus also includes a second inflatable curtain inflatable between the side structure and an occupant of the second row seat. A second gas generating cord generates inflation fluid for inflating the second inflatable curtain. The apparatus further includes a controller that is operable to cause selective actuation of one or both of the first and second gas generating cords.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The foregoing and other features of the present invention will become apparent to one skilled in the art to which the present invention relates upon consideration of the following description of the invention with reference to the accompanying drawings, in which:  
       FIG. 1  is a schematic view of an apparatus for helping to protect an occupant of a vehicle illustrating a deflated and stored position of the protection device, according to the present invention;  
       FIG. 2  is a schematic view the apparatus illustrating an inflated and deployed position of the protection device; and  
       FIG. 3  is a schematic block diagram illustrating a portion of the apparatus of  FIGS. 1 and 2 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      As representative of the present invention, an apparatus  10  helps to protect an occupant of a vehicle  12 . As shown in  FIGS. 1 and 2 , the vehicle  12  includes a side structure  16  and a roof  18 . The roof  18  may be either a standard roof that is fixed in place or a convertible roof that can be moved or removed. The side structure  16  includes side windows  20  and extends along the length of the vehicle adjacent first row or front seating  30  and second row or rear seating  32  of the vehicle  12 .  
      The side structure  16  shown in  FIGS. 1 and 2  is on a driver side  34  of the vehicle  12 . Those skilled in the art will appreciate that the vehicle  12  also includes a similarly or identically configured side structure on a passenger side (not shown) of the vehicle. It will thus be appreciated that the apparatus  10  of the present invention may be associated with the driver side  34  or passenger side of the vehicle  12 . The apparatus  10  may help protect driver side or passenger side occupants of the first row seating  30  and second row seating  32 .  
      The apparatus  10  includes inflatable vehicle occupant protection devices in the form of inflatable curtains  40 . The inflatable curtains  14  include a first or front inflatable curtain  42  and a second or rear inflatable curtain  44 . The inflatable curtains  40  are mounted adjacent the intersection of the side structure  16  and roof  18  of the vehicle  12  and are inflatable from a deflated and stored position of  FIG. 1  to an inflated and deployed position of  FIG. 2 . The first inflatable curtain  42 , when in the inflated and deployed position, is positioned between the side structure  16  and any occupants of the first row seating  30 . The second inflatable curtain  44 , when in the inflated and deployed position, is positioned between the side structure  16  and any occupants of the second row seating  32 .  
      The apparatus  10  also includes an inflation fluid source  50  for providing inflation fluid for inflating the inflatable curtains  40 . The inflation fluid source  50  provides a volume of inflation fluid sufficient to inflate the inflatable curtains  40  and maintaining the curtains in the inflated and deployed position ( FIG. 2 ) for a desired duration, such as at least two seconds, at least five seconds, or longer.  
      The inflation fluid source  50  comprises a first or front gas generating cord  52  associated with the first inflatable curtain  42 , and a second or rear gas generating cord  54  associated with the second inflatable curtain  44 . The gas generating cords  52  and  54  include an ignitable gas generating material that is distributed along the length of the cords. The gas generating cords  52  and  54  may have any known construction. For example, the gas generating cords  52  and  54  may have any of the constructions disclosed in U.S. Pat. No. 6,062,143, issued to Simula, Inc. of Phoenix, Ariz.  
      The apparatus  10  may also include one or more housings  46  that store the inflatable curtains  40  in the deflated and stored position. The deflated inflatable curtains  40  and housings  46  have an elongated configuration and extend along the vehicle roof  18  and along the side structure  16  of the vehicle  12  above the side windows  20 . The housings  46  may have a variety of constructions. For example, the housings  46  may comprise fabric sheaths or plastic housings. The apparatus  10  may also include means  48 , such as clamps or brackets, for connecting the inflatable curtains  40 , housings  46 , and gas generating cords  52  and  54  to the vehicle  12 .  
      The inflatable curtains  40  may have any suitable construction. For example, referring to  FIG. 2 , the inflatable curtains  40  may include panels  60  of material that are arranged in an overlying manner and that have portions secured together. For instance, the panels  60  may be secured together along at least a portion of perimeters of the inflatable curtains  40  to form perimeter connections  62  of the curtains. The perimeter connections  62  may help define inflatable volumes  64  of the inflatable curtains  40 .  
      The inflatable curtains  40  may also include interior connections  66  in which the overlying panels  60  are secured together within the perimeter of the curtains. The interior connections  66  form non-inflatable portions of the inflatable curtains  40 . The interior connections  66  also help define inflatable chambers  68  of the inflatable curtains  40 . The configuration of the interior connections  66  and the chambers  68  may vary depending on a variety of factors, such as the architecture of the vehicle  12 , the position of the inflatable curtains  40  in the vehicle, and the desired extent or coverage of the curtains. For example, the configuration of the interior connections  66  and the inflatable chambers  68  of the front inflatable curtain  42  may be different than the configuration of the interior connections and inflatable chambers of the rear inflatable curtain  44 .  
      The perimeter connections  62  and interior connections  66  may be formed in a variety of manners. For example, the connections  62  and  66  may be formed by weaving the panels  60  as a single piece of material. Alternatively, the connections  62  and  66  may be formed by stitching the panels together, or interconnecting the panels by ultrasonic welding, heat bonding, adhesives, or a combination of these methods.  
      The panels  60  may be woven from a material, such as nylon yarn or polyester yarn. A sealant may be applied to the panels  60  to give the inflatable curtains  40  a desired degree of gas permeability. For example, the sealant may provide the inflatable curtains with a substantially gas impermeable construction. The panels  60  may have alternative constructions, such as a plastic film construction or a multilayered construction including fabric layers, plastic film layers, or both fabric layers and plastic film layers.  
      The apparatus  10  also includes an actuation system  80  for actuating the first and second gas generating cords  52  and  54  in response to an event for which inflation of the curtains  40  is desired, such as a vehicle collision, a vehicle rollover, or both. According to the present invention, the actuation system  80  may actuate the first gas generating cord  52 , second gas generating cord  54 , or both, in response to the event for which inflation of the curtains  40  is desired.  
      Referring to  FIG. 3 , the actuation system  80  includes one or more vehicle condition sensors  82 , one or more occupant condition sensors  84 , a controller  86 , and an actuator  88 . The vehicle condition sensors  82  are operative to sense vehicle conditions that indicate the occurrence of an event for which occupant protection is desired. For example, as shown in  FIG. 3 , the vehicle condition sensors  82  may include one or more impact sensors  90 , one or more rollover sensors  92 , or a combination of impact and rollover sensors. The impact sensors  90  may be operative to sense a variety of vehicle impacts, such as side impacts, front impacts, rear impacts, offset impacts, and angled impacts. The information provided by the vehicle condition sensors  82  thus may be used to determine whether inflation of one or both of the inflatable curtains  40  is necessary.  
      The vehicle condition sensors  82  may also be operative to sense vehicle conditions that indicate which of the inflatable curtains  40  to inflate. For example, as shown in  FIG. 3 , the vehicle condition sensors  82  may include seatbelt latch sensors  94 , seatbelt tension sensors  96 , seat position sensors  98 , or a combination of these sensors.  
      The seat belt latch sensors  94  are operative to detect a latched condition of the seat belt buckle associated with a particular vehicle seat. The seat belt tension sensors  96  are operative to detect the amount of tension on a seat belt associated with a particular vehicle seat. The seat position sensors  98  may be operative to sense a variety of seat position characteristics for a particular vehicle seat, such as a forward/rearward position of the seat and an forward/rearward tilt position of the seat.  
      The occupant condition sensors  84  are operative to sense occupant conditions that may be used to determine which of the inflatable curtains  40  to inflate. For example, the occupant condition sensors  84  may include an occupant position sensor  110 , an occupant weight sensor  112 , an occupant presence sensor  114 , or a combination of these sensors.  
      The occupant position sensor  110  may be a device, such as an ultrasonic transducer, that is operative to provide an output indicative of an occupant&#39;s position in the vehicle  12 . For example, the occupant position sensor  110  may be used to determine an occupant&#39;s position relative to vehicle structure, such as the side structure  16 , or relative to an expected deployment trajectory of the inflatable curtain  40 . It will be appreciated that such an ultrasonic transducer may also be operative to provide an output indicative of an occupant&#39;s size. The occupant presence sensor  114  may be a device, such as a switch mounted on the vehicle seating  30  and  32 , that is actuated and provides a corresponding output in response to an occupant&#39;s presence on the seat.  
      The controller  86  may include one or more electronic devices suited to perform the control functions described herein. For example, the controller  86  may include one or more microcontrollers, microprocessors, state machines, discrete components, one or more application specific integrated circuits (“ASIC”), or a combination of these electronic devices. The controller  86  is operative to receive signals from the vehicle and occupant condition sensors  82  and  84 . The controller  86  is operative to evaluate these vehicle and occupant condition signals in order to determine whether to actuate one or both of the inflatable curtains  40 . This function may be implemented in the controller  86  with software or a combination of hardware and software.  
      The actuator  88  is operative to selectively actuate one or both of the inflatable curtains  40  in response to an actuation signal received from the controller  86 . The actuator  88  is also operative to actuate one or both of the gas generating cords  52  and  54  in response to the actuation signal. As shown generally at  100  in  FIG. 3 , the controller  86  and actuator  88  may be incorporated into a single device or unit.  
      The vehicle condition sensors  82  and occupant condition sensors  84  monitor their respective conditions continuously or routinely during operation of the vehicle  12 . Upon the occurrence of an event for which inflation of a curtain  40  is desired, the appropriate vehicle condition sensor  82  provides a signal, indicative of the sensed event, to the controller  86 . For example, upon the occurrence of a vehicle impact, one or more vehicle impact sensors  90  may provide a signal indicative of the sensed impact event to the controller  86 . As another example, upon the occurrence of a vehicle rollover, one or more vehicle rollover sensors  92  may provide a signal indicative of the sensed rollover event to the controller  86 . In response to receiving this signal from the vehicle condition sensor  82 , the controller  86  determines whether to actuate the front gas generating cord  52  to inflate the front inflatable curtain  42 , the rear gas generating cord  54  to inflate the rear inflatable curtain  44 , or both gas generating cords to inflate both inflatable curtains.  
      To determine whether to actuate the front gas generating cord  52 , the rear gas generating cord  54 , or both gas generating cords, the controller  86  takes into account vehicle condition data provided by the vehicle condition sensors  82 , occupant condition data provided by the occupant condition sensors  84 , or both vehicle and occupant condition data. For example, the controller  86  may inhibit inflation of an inflatable curtain  40 , such as the front passenger side curtain, a rear curtain, or a combination of these curtains, if a determination is made that the vehicle seat corresponding to these curtains is unoccupied. The unoccupied seat condition may be determined from data provided by one or more of the occupant condition sensors  84 , such as the occupant position sensor  110 , the seat weight sensor  112 , the occupant presence sensor  114 , or a combination of these sensors.  
      As another example, the controller  86  may inhibit inflation of an inflatable curtain  40 , such as the front passenger side curtain, a rear curtain, or a combination thereof, if a determination is made that the corresponding seat is occupied by an object other than an occupant. For instance, the seatbelt latch sensor  94  and tension sensor  96  may indicate that the seatbelt buckle is latched and the belt is under high tension. This may indicate that a child safety seat is cinched down tightly in the seat. In this instance, it may be desirable to inhibit actuation of the corresponding inflatable curtain  40 .  
      As a further example, the controller  86  may inhibit inflation of an inflatable curtain  40 , such as the front passenger side curtain, a rear curtain, or a combination thereof, if a determination is made that the occupant of the seat is positioned away from a normal seated position. For instance, the occupant position sensor  110  may indicate that an occupant is leaned against the vehicle side structure  16 , e.g., an occupant sleeping in the passenger seat. In another instance, the occupant position sensor  110  may indicate that an occupant is positioned in the expected deployment trajectory of the inflatable curtain  40 . In either of these instances, it may be desirable to inhibit actuation of the corresponding inflatable curtain  40 .  
      Once the controller  86  determines which of the inflatable curtains  40  to inflate, the controller provides an appropriate signal to the actuator  88 . The actuator  88  actuates the front gas generating cord  52 , the rear gas generating cord  54 , or both the front and rear gas generating cords in response to the signal from the controller  86 . Upon actuation, the front and rear gas generating cords  52  and  54  generate inflation fluid for inflating the front and rear inflatable curtains  42  and  44 , respectively.  
      The inflatable curtains  42  and  44  inflate under the pressure of the inflation fluid from their respective gas generating cords  52  and  54 . The housings  46  open and the inflatable curtains  42  and  44  inflate and deploy in a direction away from the roof  18  in a downward direction as shown in the drawings and in a downward direction with respect to the direction of forward travel of the vehicle  12  into the inflated and deployed condition of  FIG. 2 .  
      The inflatable curtains  42  and  44 , when inflated, extend along the side structure  16  of the vehicle  12  and are positioned between the side structure and any occupants of the first and second row seating  30  and  32 , respectively.  
      From the above description of the invention, those skilled in the art will perceive improvements, changes and modifications. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.