United States Patent [19]
`Lohr et al.
`
`[54} ENERGY ABSORPTION ARRANGEMENT IN
`VEHICLE PASSENGER RESTRAINT
`SYSTEM
`[75] Inventors: Thomas E. Lohr, Warren; John J.
`Sack, Bloomfield Hills, both of
`Mich.
`[73] Assignee: Allied Chemical Corporation, New
`York, N.Y.
`Nov. 10, 1972
`[22] Filed:
`[21] Appl. No.: 305,383
`-
`Related U.S. Application Data
`[63) Continuation of Ser. No. 83,557, Oct. 23, 1970,
`abandoned.
`
`[52] U.S. Cl........................................... 280/150 AB
`[51] Int. Cl............................................. B60r 21/10
`[58] Field of Search................ 280/150 AB; 55/380;
`244/145
`
`[56]
`
`3,204,391
`
`References Cited
`UNITED STATES PATENTS
`9/1965 Schwab................................. 55/380
`
`3,900,210
`[11]
`[45] Aug. 19, 1975
`
`Boone................................. 244/145
`12/1965
`3,222,016
`1/1968 Lagerstrom........................... 55/380
`3,364,663
`6/1969 Carey........................... 280/15() AB
`3,451,693
`3,473,824 10/1969 Carey et al..
`... 280/150 AB
`3,476,402 11/1969 Wilfert......................... 280/15() AB
`3,618,979 1 1/1971
`Gulette..... ----------------- 280/150 AB
`3,761, l l I
`9/1973 Kemper........................ 280/15() AB
`
`Primary Examiner—Kenneth H. Betts
`Attorney, Agent, or Firm—Ernest D. Buff; Jonathan
`Plaut
`
`ABSTRACT
`[57]
`This invention relates to energy absorption in a pas
`senger restraint system as a result of the use of an ex
`pansible barrier contained within the passenger re
`straint bag. More specifically, this invention relates to
`the introduction of an energy absorbing elastic bag or
`other barrier material within the air bag which is uti
`lized to restrain forward motion of a passenger within
`a motor vehicle.
`3 Claims, 4 Drawing Figures
`
`
`
`IPR 2016-01794
`American Vehicular Sciences
`Exhibit 2031
`
`

`

`PATENTEDMU?, 19875
`
`bi-- i jf 2
`
`T, GOO, 21 O
`
`
`
`|NVENTORS:
`JOHN J. SACK
`THOMAS E, LOHR
`BY
`. . .
`\ . . . . .
`ATTORNEY
`
`

`

`PATENTED AUC 191975
`
`-
`
`3,900, 21 O
`
`O
`
`16 O
`
`17O
`
`| 80
`
`É
`
`O
`
`[5
`3O
`4.5
`TIME (MILLISEcon Ds)
`
`60
`
`FIG. 4.
`
`
`
`O
`
`| 80
`
`:
`
`TIME (MILLISECONDS)
`
`| NVENTORS:
`JOHN J. SACK
`THOMAS E. LOHR
`BY
``--~49-s
`AT TORNEY
`
`

`

`15
`
`-
`
`level of inflation.
`
`3,900,210
`2
`1.
`for absorption of kinetic energy of the inflating me
`ENERGY ABSORPTION ARRANGEMENT IN
`dium. However, among other differences, the inner
`VEHICLE PASSENGER RESTRAINT systEM
`barrier is not disclosed as stretchable to take the shape
`of the outer bag and dissipate over a period of time the
`This is a continuation of application Ser. No. 83,557,
`energy of the inflating medium, resulting in the peak
`filed Oct. 23, 1970 now abanded
`sound reduction desired, but rather in Carey et al, the
`This invention relates to energy absorption in a pas
`inner barrier merely unfolds and then bursts or other
`senger restraint system as a result of the use of an ex
`pansible barrier contained within the passenger re
`wise emits the inflating medium into the outer bag.
`Where Carey et al provides for a baffle, the energy ab
`straint bag. More specifically this invention relates to
`sorbing characteristic of stretching is also unprovided
`the introduction of an energy absorbing elastic bag or
`other barrier material within the air bag which is uti
`for, since gas in one embodiment is circulated around
`the outside thereof, and the baffle is generally used
`lized to restrain forward motion of a passenger within
`a motor vehicle. Particularly, the energy absorbing
`only as a deflection barrier.
`-
`Describing in further detail in relation to the draw
`elastic barrier acts to dissipate the total amount of en
`ergy of the fluid material which inflates the passenger
`ings:
`FIG. 1 shows the embodiment of the invention in
`restraint air bag, and especially to reduce the sound
`which an energy absorbing expandable inner bag is lo
`One of the principal problems in the inflation of pas
`cated within the passenger restraint outer bag;
`senger restraining air bags by a generated gas or gas
`FIG. 2 is a second embodiment of the invention:
`FIG. 3 shows sound pressure versus time where this
`from a component gas source, or a combination of the
`20
`two, is the audible sound caused by a rapid movement
`invention is not employed; and
`- -
`-
`FIG. 4 shows the same components of data as in FIG.
`of the gas into the passenger restraint bag. The level of
`3 where an embodiment of the invention is employed.
`sound produced is not uniform in the prior art, as will
`According to the invention, an inflating medium is
`be described hereinafter in detail, and such sound pro
`obtained from a source 1, as is well known in the art.
`duced will peak at high and potentially unacceptable
`25
`For example, the inflating medium, which is gas ob
`levels, such as in the range of 168–170 decibels.
`tained from either a gas generator system or a com
`It is therefore an object of this invention to provide
`pressed gas source, or a combination of the two. The
`for the absorption of the energy of the gas expanding
`inflating medium is directed at least partially toward an
`an air bag restraint system, such that the total amount
`of energy produced for inflation of the air bag is dissi
`energy absorber in the form of an expandable, elastic
`30
`barrier. In the embodiment of FIG. 1, the inflating
`pated over a period of time and the peak levels of
`means is directed into an expandable, elastic inner bag
`sound pressure are reduced so that decibel level is low
`2, said bag having elastic walls which extend under
`ered into an acceptable range. In addition, it is an ob
`pressure, said inner bag being contained within an
`ject of this invention to absorb heat and smoke pro
`35
`outer passenger restraint bag 4. In the embodiment
`duced by the use of the inflatable gas medium and to
`shown in FIG. 1, all of the inflating material is directed
`allow for a redundancy advantage, as will be described
`into the inner bag, but in the alternate only a portion
`in more detail hereinafter.
`-
`of the inflating material may be directed into the inner
`These and other objects and advantages will become
`bag, the rest of the inflating material entering directly
`more apparent in the context of the following more de
`40
`tailed description of the invention.
`into the outer bag.
`-
`In this embodiment, the inner bag is preferably knit
`Generally, energy absorbing means are provided
`and made, for example, of nylon or polyester material.
`within a passenger restraint bag, typically to be found
`Other materials may also be utilized. The outer bag
`within an automobile. The energy absorbing means is
`may, for example, be woven. The knitting and weaving
`in the form of stretchable barrier, in one embodiment
`45
`operations of course, are known and not the object of
`a second more elastic smaller inner bag located within
`this invention. The inner knit bag of one embodiment
`the elastic outer bag. The inner bag may be porous so
`will stretch on filling in the range of at least 50–100%
`that gas entering into it will be emitted into the outer
`of its original volume and thus absorb the energy of the
`bag. This energy absorbing, elastic inner barrier, in one
`inflating material entering thereinto, dissipating the
`embodiment the inner bag, due to its elastic quality ex
`50
`total amount of said energy over a period of time and
`pands to take the shape of the outer bag. The absorp
`reducing the peak sound level of said energy. The inner
`tion of that energy by the inner barrier as a result of its
`elastic bag will move in a direction so as to conform to
`elastic movement under the pressure of the energy en
`the space of the outer bag as it expands toward it and
`tering thereinto dissipate the total amount of said en
`will contain heat and smoke which may accompany the
`ergy over a period of time and reduces the peak decibel
`55
`inflating material. In an alternative embodiment, the
`level of said energy. When the energy of the inflating
`outer bag may be stretchable too, over its original in
`material is directed against the wall of the energy ab
`flatable volume, so that both bags will function to dissi
`sorber, it stretches, breaking up the energy wave. This
`pate the energy of the inflating medium.
`results in a lowering of the peak decibel range of the
`In the case of the knitted inner bag, as the bag ex
`system.
`pands the spaces between the knitted material will
`In addition, the energy absorption expansion barrier
`open and movement of inflating material therethrough
`in the form of the inner bag contains heat and smoke,
`from the inner bag to the outer bag (as shown in FIG.
`where they exist, of the inflating medium and provides
`a redundancy advantage in that if said expansion me
`1) will be facilitated.
`In FIG. 2, an alternative embodiment to the expand
`dium should fail, the outer bag would still function to
`65
`able inner bag shown in FIG. 1, the energy absorber is
`provide passenger restraint.
`the form of an expandable elastic barrier, or mem
`The U.S. Pat. to Carey et al No. 3,473,824 discloses
`brane, which is located within the outer bag 4 and
`a system with inner barrier and outer bag arrangement
`
`-
`
`-
`
`60
`
`

`

`3,900,210
`
`3
`which is attached to the inner side walls of said outer
`bag at point 6 and 7, for example. The expandable elas
`tic barrier 5 furnishes similar energy absorbtion to that
`furnished by the inner bag 2, in that it stretches as a re
`sult of the pressure of the energy of the inflating mate
`rial in one embodiment at least 50–100% its original
`size, and dissipates that energy over a period of time.
`The expandable barrier 5 may be made porous as de
`scribed with relation to the inner bag 1, by knitting it,
`as previously discussed. Of course, when the expand
`able barrier 5 is utilized, in comparison to the inner bag
`of FIG. 1, the inflating material enters directly into the
`outer bag 4.
`The result of employing an energy absorber in the
`form of an expandable elastic barrier may be obtained
`from a comparison of the charts of FIGS. 3 and 4. In
`the example of the chart of FIG. 3, the inflating mate
`rial enters directly into an outer passenger restraint
`bag, without any energy absorbing means in a form of
`expandable barrier. In the chart of FIG. 4, an energy
`absorber in the form of an inner expandable, elastic
`knitted bag, as in FIG. 1, was employed. In both cases,
`it was necessary to work within the parameter of full
`inflation of the outer bag within 40 millisecs, as such is
`the accepted period of time by which full bag inflation
`of passenger restraint must occur. The charts are a
`sound recording gained from an oscilloscope record
`lºng.
`i. the case of the chart of FIG. 3, the sound level in
`decibels produced by movement of the inflating me
`dium into the outer bag is irregular and peaks on the
`positive side between 168–170 decibels, which is equiv
`alent to about 64,512 dynes/sq.cm. Where the inner ex
`pandable , elastic bag was utilized, the total amount of
`energy of the inflating material was dissipated over a
`period of time as shown in FIG. 4 and the maximum
`decibel range was 155–157 decibels, which is the
`equivalent of 21,500 dynes/sq.cm. The reduction in
`
`15
`
`25
`
`4
`
`sound level is significant.
`Of course, this invention is not concerned with the
`use of a lower torso restraint, which also may be em
`ployed within the outer bag as a matter of choice.
`Although the invention has been described with rela
`tion to two embodiments, it is understood that the in
`tention is that it only be limited by the scope of the fol
`lowing claims and not by the apparatus, materials, or
`methods of employing them as recited above.
`We claim:
`1. A restraint system comprising an outer bag
`adapted to be filled with an inflating gas, said outer bag
`being composed of nylon and being stretchable over its
`original inflated volume, an energy absorbing elastic
`knitted inner bag having apertures therein and located
`within said outer bag, means for passing said inflating
`gas through said apertures and into said outer bag to
`stretch said inner bag in the range of at least 50-100
`percent of its volume without bursting said inner bag
`2. Restraint system of claim 1, said inner bag being
`formed of nylon.
`3. Method of lowering the sound level of the inflation
`of a restraint system having an outer bag adapted to be
`filled with an inflating gas, said outer bag being com
`posed of nylon and being stretchable over its original
`inflated volume, and an energy absorbing elastic knit
`ted inner bag having apertures therein, said inner bag
`being of smaller dimension and more elastic than said
`outer bag, comprising the steps of circulating at least a
`portion of said inflating gas against said inner bag
`within said outer bag to stretch said inner bag in the
`range of at least 50-100 percent of its volume without
`bursting said inner bag and thereby absorb energy of
`said gas and to cause said inner bag on filling to con
`form to the shape of said outer bag, and passing said in
`flating gas through said apertures during stretching of
`said inner bag.
`
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`:k : sk
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`45
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`5 5
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`65
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`

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`UNITED STATES PATENT OFFICE
`CERTIFICATE OF CORRECTION
`3,900, 210
`8 PATENT No.
`: August 19, 1975
`DATED
`INVENTOR(S) : Thomas E. Lohr and John J. Sack
`It is certified that error appears in the above-identified patent and that said Letters Patent
`C are hereby corrected as shown below:
`
`C
`
`Column 4, line 19, after "bag" insert the following -- during
`filling of said outer bag, said inner bag being of
`smaller dimension and more elastic than said outer
`bag and being so shaped and stretchable on filling
`as to conform to the shape of said outer bag when
`said outer bag is filled with said gas. --
`Signed and gealed this
`ninth Day of December 1975
`
`-
`{SEAL}
`
`Attest:
`
`G
`
`-
`
`RUTH C. MASON
`At testing Officer
`
`C. MARSHALL D ANN
`Commissioner of Patents and Trademarks
`
`
`
`