IPR2016-01794
`American Vehicular Science, LLC
`Exhibit 2004
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`1
`PROTECTIVE DEVICE
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`REFERENCE TO PRIOR APPLICATION
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`This invention is related to the invention disclosed in
`the copending application of Robert H. Graebe, Serial
`No. 781,472 filed December 5, 1968 now U.S. Pat. No.
`3,605,145.
`
`BACKGROUND OF THE INVENTION
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`This invention relates in general to protective de-
`vices, and more particularly to a protective device for
`containing and cushioning individuals from severe im-
`pacts.
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`It has been suggested that automotive vehicles be
`provided with inflatable bags which are normally stored
`in a deflated condition withinthe passenger compart-
`ment, and are rapidly inflated from a gas generator
`when the vehicle is subjected to a severe impact. The’
`inflatable bags heretofore envisioned can be quite
`large, and must be deployed from one central exit
`point. The speed of deployment is therefore limited by
`the amount of unfolding which must occur. During this
`unfolding operation very little impact protection is
`available to theoccupant. In other words, the bags
`must be nearly fully inflated to provide adequate pro-
`tection, but often sufficient time is not available to ef-
`fect a complete inflation. Also, while a single bag may
`provide some measure of protection against purely
`head-on impacts, it will not adequately confine the in-
`dividuals behind it against lateral movement or other-
`wise prevent them from being thrown about the passen-
`ger compartment should the vehicle turn over-or be
`subjected to lateral impacts. In this same vein, such
`bags do not provide sufficient protection and can
`lnjure the so-called out~of-position occupants, that is
`those passengers who are not occupying normal seat
`positions at the time of the collision. Moreover, the de-
`ployment of large bags is usually accompanied by noise
`of extremely large magnitude, and this noise could"
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`prove damaging to the ears.
`SUMMARY OF THE INVENTION
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`One ofthe principal objects of the present invention
`is to provide a protective device which is stored in an
`extremely compact condition, but which will rapidly
`inflate uniformly, upon receiving a proper signal from
`a crash sensor when the vehicle is subjected to a severe
`impact,
`to cushion the occupant from the interior
`structures of the vehicle. Another object is to provide
`a protective device of the type stated which substan-
`tially envelops the occupants of the vehicle so that they
`are completely contained and will not shift about the
`interior of the passenger compartment during a crash.
`A further object is to provide a protective device of the
`type stated which provides protection against lateral
`impacts and protection for out-of-positlon occupants.
`An additional object is to provide a protective device
`of the type stated which deploys at a relatively low
`sound level, and provides a high degree of protection
`as it deploys. Still another object is to provide a protec-
`tive device of the type stated having a secondary energy
`absorption medium as back-up cushioning. Yet another
`object is to provide a protective device which does not
`significantlydetract from the space available within the
`passenger compartment or from the appearance of the
`passenger compartment wheninot in use. Anadditional I
`object is to provide a protective device of the type
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`stated which provides rebound control, continues to
`maintain protection for multiple impacts, and does not
`hinder the breathing of one confined by it. An addition]
`object is to minimize injury to the occupant from the
`restraintdevice itself. Another object is to provide a
`means of attaining a high degree of reliability that a
`proper inflation will occur. These and other objects and
`advantages will become apparent hereinfater.
`The present invention is embodied in a protective de-
`vice including flexible tube-like elements which are
`norm-ally housed in pockets and when inflated project
`beyond the pockets to form a protective cushion.
`The invention also consists in the parts and in the
`combinations of parts hereinafter described and
`claimed.
`
`DESCRIPTION OF THE DRAWINGS
`
`In the accompanying drawings which form part of the
`specification and wherein like numerals refer to like
`parts wherever they occur.
`FIG. 1 is a fragmentary sectional view of an automo-
`bile provided with a protective device constructed in
`accordance with and embodying the present invention;
`FIG. 2 is a perspective view, partially broken away
`and in section, of the protective device;
`FIG. 3 is a fragmentary sectional view taken through
`some of the pockets of the protective device;
`FIG. 4 is a top view showing the protective device in-
`flated and cushioning a passenger of an automotive ve-
`hicle; and '
`FIG. 5 is a fragmentary sectional view showing the
`porting in a modified form of the protective device.
`DETAILED DESCRIPTION
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`Referring now to the drawings, 2 (FIG. 1) designates
`a protective device for protecting the occupants of the
`passenger compartment 4 of an automobile or other ve-
`hicle. The passenger compartment 4 contains a seat 6
`which is anchored to a floor 8 and faces toward a wind-
`shield 10 and a firewall 12 both of which define the
`front of the passenger compartment 4. The sides of the
`passenger compartment 4 are closed by doors 14, while
`the top is closed by a roof 16. Positioned in front of the
`firewall 12 is a dashboard 18, and the dashboard 18
`supports and contains the protective device 2, which
`when deployed substantially fills the front part of the
`passenger compartment 4 with long and slender in-
`flated elements capable of cushioning impacts resulting
`from collisions or from the vehicle overturning.
`The protective device 2 includes a compressed gas
`cylinder 20 which is mounted in a fixed position behind
`the dashboard I8. Disposed in front of the cylinder 20
`is a manifold 22 which is configured to generally wrap
`around the forwardly presented side of the cylinder 20
`so that the manifold 22 possesses a generally arcuate
`shape. At its head end the cylinder 20 is provided with
`an explosive, an electrically, or a mechanically oper-
`ated valve 24 which is normally closed and is energized
`by a sensing element or crash sensor (not shown). The
`sensing element is conventional and is responsive to im-
`pacts. When such an impact is detected an electric cur-
`rent or other properly conditioned signal is directed to
`the valve 24 which opens and allows the stored con-
`tents of the cylinder 20 to discharge as a high pressure
`gas. The valve 24 and manifold 22 are connected
`through a tube 26 so that when the valve 24 opens, the
`compressed gas is released into the manifold 22. The
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`manifold 22 has a multiplicity of tube-like exhaust
`ports 28 projecting from its rearwardly presented face
`at closely spaced intervals, and these ports 28 are
`slightly enlarged at their outer ends in the formation of
`slight flanges 30. Finally, the manifold 22 is provided
`with a release valve 31 which is timed to open at the
`end of a predetermined period after the sensing ele-
`ment is activated.
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`In lieu of the compressed gas cylinder 20, a solid state
`gas generator may be utilized to supply the high pres-
`sure gas. These devices, upon receiving a signal from
`the crash sensor, generate gas and discharge it at high
`pressure.
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`The rearwardly presented face of the manifold 22,
`that is, the face presented rearwardly toward the pas-
`senger compartment 4 and seat 6 therein may be cov-
`ered by a housing or padding material 32 of substantial
`thickness, and this material is preferably a foamed or
`cellular plastic such as polyurethane. The padding ma-
`terial 32 has sufficient body to remain self-standing and
`only deforms when subjected to outside forces such as
`those occasioned by a passenger bumping intoit. The
`padding material 32 projects outwardly considerably
`beyond the outer ends of the ports 28, and at each port
`28 is provided with a generally cylindrical pocket 34 so
`that the ports 28 are disposed within the pockets 34.
`The pockets 34 extend completely through the padding
`material 32 and at their outer ends are closed by cover
`devices 36 which normally lie flush with the exposed
`surface of the padding material 32. The devices 36,
`however, are mounted such that they swing outwardly
`or otherwise leave their covering position when sub-
`jected to outwardly directed forces from within the
`pockets 34.
`In addition to the exhaust ports 28, each pocket 34
`further contains a flexible tube element 40 which is
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`normally deflated and coiled or otherwise disposed in
`a highly compact configuration so that it will fit entirely
`within its pocket 34. Preferably, the tube elements 40
`are formed from a flexible material. Each tube element
`40 includes an elongated body 42 of substantially uni-
`form or tapered diameter. At its one end the body 42
`is closed, while at its opposite end it merges into a neck
`44 which fits over the exhaust port 28 within the pocket
`34. The neck 44 is retained on the exhaust port 28 by
`a cinch ring 46 which embraces the neck 44 and the
`port 28 between the slight flange 30 and the manifold
`22. When the tube elements 40 are elongated, that is
`when they are inflated, they possess sufficient length to
`reach almost to the seat 6.
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`Should the vehicle having the protective device 2
`therein become involved in a collision, the sensing de-
`vice will be activated, and it will cause energy to be-
`come available to operate the valve 24. The valve 24,
`in turn, will release the contents of the cylinder 20 and
`allow that gas to flow through the tube 26 and into the
`manifold 22. If a solid state gas generator is used, the
`sensing device will activate the generator and cause it
`to generate high pressure gases which likewise will be
`directed through the tube 26 to the manifold 22. The
`pressurized gas within the manifold 22 exhausts into
`the coiled tube elements 40. As the tube elements 40
`expand within their respective pockets 34, they bear
`against the cover devices 36 and dislodge them from
`their covering positions over the pockets 34. Thereaf-
`ter, the tube elements 40 expand through the passenger
`compartment 4 toward the seat 6 and bear against pas-
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`sengers seated upon the seat 6 (FIGS. 1 and 4). In this
`connection,
`it should be noted that the incline and
`shape of the open ends for the various pockets 34 is
`such that the inflated tube elements 40 expand through
`substantially the entire forward portion of the passen-
`ger compartment 4. The foregoing events occur within
`a fraction of a second and cause a useful surface to be
`deployed uniformly and synchronously throughout its
`entire length of travel and before the forward momen-
`tum of the passengers bring them to the dashboard 18.
`Since the exhaust ports 28 are closely spaced on the
`manifold 22, the elongated bodies 42 of the tube ele-
`ments 40 substantially fill that part of the passenger
`compartment 4 located immediately behind the dash-
`board 18 and windshield 10, so that during the impact
`the passengers are prevented from being hurled against
`the windshield 10 or rigid structural portions of the ve-
`hicle. Instead the passengers sink into the multitude of
`inflated elements 40 located ahead of them and this of
`course cushions the impact significantly. In some vehi-
`cles it may be desirable to concentrate more flexible
`tube elements in one part of the passenger compart-
`ment 4 than other parts, and this is easily accomplished
`by varying the angles and shapes of the pockets 34 at
`their open ends. Thus, the tube elements 40 can be di-
`rected to bunch together, and likewise to extend into
`remote areas. Inasmuch as the tube elements 40 are
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`structurally independent of one another the expansion
`of each tubular element 40 is not in any way inhibited
`by adjacent tube elements 40. Therefore, while one ele-
`ment may engage one of the passengers and be pre-
`vented from fully expanding thereby, other elements 40
`will expand fully toward the seat 6, thus providing cush-
`ioning to the sides and top of the passengers so as to
`completely confine them in the event of a collision.
`This ability of the protective device 2 to completely
`confine and contain passengers is extremely valuable in
`collisions
`involving subsequent
`lateral
`impacts or
`where the vehicle rolls over. The presence of a multi-
`plicity of tube elements 40, instead of a single large air
`bag, causes only the deployment energies of those tube
`elements 42 that engage the occupant to be absorbed
`by the occupant which greatly reduces the chances of
`injury to the occupant over those of a large bag. To re-
`tain the tube elements in a gathered or bunched ar-
`rangement so that they do not spread excessively when
`a passenger sinks into them, the tube elements at the
`periphery of the pattern may be connected together
`through a string or elastic band.
`The multiplicity of tube elements also causes acous-
`tic attenuation so that the sound level at deployment is
`not nearly as great as the air bag type of protective de-
`vice. In other words, each tube element can be made
`to deploy_at a slightly different rate causing out-of-
`phase sound pressure fronts which will tend to cancel
`themselves out and the space between each tube ele-
`ment helps to trap acoustic energies.
`'
`To enhance the cushioning effect orifices may be
`provided at each port 28 so that when a flexible ele-
`ment 40 is compressed due to the inertial force of a
`passenger against it, it will not deflate rapidly, but in-
`stead will deflate at a controlled rate. When orifices are
`employed, they can be used in conjunction with check
`valves or can be incorporated into a differential flow
`valve which will permit rapid inflation of flexible ele-
`ments 40.
`In other words,
`the presence of orifices
`should not in any way impede the inflation of the flexi-
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`fold 22 used when ventilated tube elements 40 are used
`to effect rebound control.
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`ble elements 40, for it is important to have them deploy
`in the shortest possible time.
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`If the impact is severe enough to completely collapse
`the tubular elements 40, the padding material 32 will
`provide back-up cushioning. As previously noted, the
`rate of energy absorption can be controlled by install-
`ing an orifice at the base of each flexible tube element
`40. Likewise, it can be altered by varying the elasticity
`that each tube element 42 possesses". The gas entrapped
`in each tube element 42 that is being collapsed by the
`occupant, is caused to flow into the manifold and will
`pass into other flexible tube elements 42. When the re-
`straining forces caused by the impact are over, the '2
`compressed gas which is now stored in the unengaged
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`flexible tube elements will flow back, at a rate which
`prevents rebounding the occupant, into previously col-
`lapsed flexible tube elements that were engaged by the
`constrained occupant. This mode of operation makes
`the system available for successive impacts until such
`time as the timed release valve 31 located on the mani-
`fold 22 is opened to deflatethe system to assist in-disen-
`gaging the occupant. If no second impact protection is
`desired then ventilated flexible tube elements or mani-
`fold can be used which need not be intercommu-
`nicated.
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`Should the vehicle provided with the modified em-
`bodiment of the protective device 2 become involved
`in a collision, the sensing device will divert electrical
`current to the detonator 76 to ignite the explosive
`charge 78. This explosion will drive the pin 80 rear-
`wardly and cause its point 82 to puncture the seal 69,
`thereby" releasing the compressed gas or activating the
`gas generating material contained within the cylinder
`66. Much of the gas is diverted upwardly at the dish-
`shaped deflecting surface 74. This gas flows through
`the ports 71 and into the interior of the tube elements
`40. As each tube element 40 inflates, it expands out-
`wardly and leaves its pocket 34, as previously dis-
`cussed. The foregoing is, of course, repeated at each
`pocket 34 so that a cushion of tube elements 40 is
`formed in the front of the passenger compartment 4.
`The remainder of the gas from each cylinder 66 passes
`through the oblique passageways 84 in the detonator
`. 76 and thence into the interior of the manifold 22, so
`that the manifold is likewise pressurized, and all tube
`elements 40 are in communication. Thus, the various
`tube elements 40 will be at the same end pressure even
`if all the gas sources did not become active and will
`exert substantially equal force on the passengers upon
`the seat 6; This multiple gas pressure source assures a
`high degree of inflation reliability. Depending on the
`, capacity of the gas source and the inflated volume of
`the protective device 2, a gas source 66 may not be re-
`quired at each tube element 40 but may be proportion-
`ally distributed throughout a manifold assembly 22 and
`have its- gas additively shared by all tube elements 40.
`Conversely, each tube element 40 may have a gas gen-
`erator 66 but only selected ones may be activated on
`the initial impact and the remaining unactivated gas
`generators 66 can be activated on successive impacts.
`This invention is intended to cover all changes and
`modifications of the example of the invention herein
`chosen for purposes of the disclosure which do not con-
`stitute departures from the spirit and scope of the in-
`vention.
`What is claimed is:
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`In a modified embodiment of the protective device 2,
`(FIG. 5), the cylinder 20, valve 24, and tube 26 are
`eliminated and the manifold 22 is sealed, except at the
`exhaust ports 28, each of which or one of a cluster is 30
`threaded internally to _receive and retain an adapter 60.
`The slight flange 30 is formed on the opposite end of
`the adapter 60 and the neck 44 of the tube element 40
`is fitted over the adapter 60 and retained thereon by
`the cinch ring 46.
`Internally, the adapter 60 is provided with a web 62
`having a conical seat 64 thereon, and the seat 64 re-
`tains the end of a small vessel or cylinder 66 of a solid
`state gas generator or contains compressed gas. Actu-
`ally, the cylinder 66 at its one end has a reduced end
`portion 68 which projects through the seat 64 and be-
`yond the web 62 where it is provided with a punctur-
`able seal 69, while at its opposite end it is dome—shaped.
`The opposite end of the adapter 60, that is the outer-
`most end, has internal threads and receives a threaded
`cap 70 which screws down against the domed end of
`the cylinder 66 and retains it in place. Both the web 62
`and the cap 70 have axially extending ports 71 which
`allow gas discharged from the neck of the cylinder 66
`to pass along the side thereof and into the tubular ele-
`ment 40.
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`The inner end of the adapter 60 is likewise threaded
`and is fitted with a plug 72 having a dish-shaped deflec-
`tor surface 74 presented toward the end portion 68 of
`the cylinder 66. The plug 72 is centrally apertured and
`fitted with an electrically operated detonator 76 which
`contains a small explosive charge 78 and a shiftable pin
`30 behind the charge 78. The pin 80 projects through
`the central aperture in the plug 72 and has a point 82
`located immediately ahead of the seal 69 at the end of 60
`the reduced end portion 68 on the cylinder 66. In addi-
`tion, the detonator 76 has several oblique passageways
`84 extending through it, and these passageways open
`into the manifold 22. The detonator 76 is connected to
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`a sensing device (not shown), which sends electrical
`current through it when an impact is detected. The
`oblique passageways 84 may be deleted and no mani-
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`1. A protective device comprising: a manifold having
`a plurality of ports facing generally inthe same direc-
`tion;
`independent flexible tube elements connected
`with the ports and normally disposed in a deflated and
`compact condition; housing means formed from a pad-
`ding material which extends across and substantially
`covers the manifold, the housing means having pockets
`in which the tube elements are disposed when deflated,
`cover devices normally closing the ends of the pockets
`to protect and obscure the tube elements contained
`therein; a source of high pressure gas connected to the
`manifold; and means for initiating the flow of gas into
`the manifold and tube elements_to inflate the tube ele-
`ments so that they expand and project outwardly from
`the pockets to form a protective cushion, the ends of
`the pockets being shaped to guide the direction the
`tube elements will take when inflated.
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`2. A protective device comprising: a manifold having
`a plurality of ports projecting therefrom and facing
`generally in the same direction; independent flexible
`tube elements connected with the ports and normally
`disposed in a deflated and compact condition, the tube
`elements having their inner ends fitted over and em-
`bracing the ports; housing means formed from a pad-
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`ding material which extends across and substantially
`covers the manifold, the housing means having pockets
`into which the ports of the manifold project and in
`which the tube elements are disposed when deflated;
`cover devices normally closing the ends of the pockets
`to protect and obscure the tube elements contained
`therein; a source of high pressure gas connected to the
`manifold; and means for initiating the flow of gas into
`the manifold and tube elements to inflate the tube ele-
`ments so that they expand and project outwardly from
`the pockets to form a protective cushion.
`3. A protective device comprising: a manifold having
`a plurality of ports facing generally in the same direc-
`tion;
`independent flexible tube elements connected
`with the ports and normally disposed in a deflated and
`compact condition; closed vessels adjacent said ports
`and having ends presented towards the manifold, the
`vessels containing compressed gas; pins for puncturing
`the ends to allow the compressed gas to flow from the
`vessels; explosive charges for driving the pins into the
`vessels; deflecting surfaces disposed between the vessel
`ends and the manifold for deflecting some of the gas re-
`leased from the vessels into the flexible tube elements
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`attached to the ports, the deflecting surfaces being ap-
`ertured so that some of the gas flows into the manifold,
`whereby the tube elements will
`inflate and expand
`away from the manifold when the vessels are punctured
`so as to form a protective cushion.
`4. A device for protecting the occupants in the pas-
`senger compartment of a vehicle during a collision, said
`device comprising: a manifold having a plurality of
`closely spaced ports facing the passenger compart-
`ment, the ports being in communication with one an-
`other through the interior of the manifold; a source of
`high pressure gas connected with the manifold; means
`for causing the source of high pressure gas to discharge
`the gas into the manifold so that the gas will flow
`through the ports; and inflatable tube elements formed
`from a flexible material with each tube element being
`substantially longer than it is wide and with the width
`being substantially less than the width of an occupant,
`each tube element further being closed at one end and
`having an opening at its other end, the open ends of the
`tube elements being connected to the manifold at the
`ports thereof with each port opening into a different
`tube element, whereby the interiors of all the tube ele-
`ments are in communication through the manifold, the
`tube elements being stored in a deflated and compact
`condition remote from the occupants and being in-
`flated to an expanded condition in which at least some
`of them engage the occupants when the high pressure
`gas is discharged into the manifold, the ports of the
`manifold being positioned in close proximity to one an-
`other so that the adjacent tube elements will be close
`to one another when inflated,
`the positioning being
`such that when the tube elements are inflated the
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`closed ends of a plurality of tube elements will engage
`an occupant both crosswise and lengthwise and as the
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`occupant sinks into those tube elements other tube ele-
`ments will be presented to the sides of the occupant to
`provide lateral confinement.
`5. A protective device according to claim 4 and fur-
`ther characterized by a housing in front of the manifold
`and having pockets aligned with the ports, each pocket
`containing a separate tube element which is housed en-
`tirely within the pocket when in its deflated and com-
`pact condition, each pocket being oriented to direct
`the tube element therein into a selected portion of the
`passenger compartment when the tube element is in-
`flated.
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`6. A protective device according to claim 5 wherein
`the ends of the pockets are normally closed by cover
`devices to obscure and protect the tube elements con-
`tained therein.
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`7. A protective device according to claim 5 wherein
`the ports project from the manifold and into the pock-
`ets; and wherein the tube elements at their inner ends
`are fltted over and embrace the ports.
`8. A protective device according to claim 5 wherein
`the housing includes a padding material presented to-
`ward the occupants and extending across and substan-
`tially covering the manifold.
`9. A protective device according to claim 4 wherein
`the source of high pressure gas comprises a closed ves-
`sel at at least some of the ports, and means for punctur-
`ing each vessel to allow gas to flow therefrom, each ves-
`sel being in communication with the interior of the tube
`element attached to the port at which it is disposed and
`with the interior of the manifold.
`
`10. A protective device according to claim 9 wherein
`the means for puncturing each vessel includes an explo-
`sive charge and a pin which is driven into the vessel by
`the explosive charge.
`11. A protective device according to claim 4 and fur-
`ther characterized by means associated with the tube
`elements for controlling the rate at which the gas is ex-
`pelled from the tube elements and discharged back into
`the manifold once the tube elements have been in-
`flated.
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`12. A protective device according to claim 11
`wherein the means for controlling the rate at which the
`gas is expelled from the tube elements comprises ori-
`fices at the open ends of the tube elements.
`13. A protective device according to claim 12
`wherein the means for controlling the rate at which the
`gas is expelled from the tube elements further includes
`check valves at the ports and oriented to permit gas to
`freely enter the tube elements and to restrict the dis-
`charge of gas from the tube elements.
`14. A protective device according to claim 11
`wherein the means for controlling the rate at which the
`gas is expelled from the tube elements does not sub-
`stantially impede the flow of gas into the tube elements.
`15. A protective device according to claim 4 wherein
`the tube elements are tapered.
`It
`It
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`t
`It