MXPA99011428A - Aspiration-type air bag inflation apparatus - Google Patents

Abstract

Aparato para inflar una bolsa de aire (16) y para reducir la velocidadde inflación de la bolsa (16) en el caso de que un ocupante de un vehículo entre en contacto con la bolsa (16) antes de queésta se encuentre completamente inflada, que comprende una unidad generadora de gas (4) para producir un gas de inflación en respuesta a un impacto predeterminado del vehículo y una unidad de aspiración (12) conectada a la unidad generadora de gas (14) y a la bolsa (16). La unidad de aspiración (12) comprende una entrada de aire ambiental (22), una cámara de mezclado (28) que estáen comunicación con la entrada de aire (22), y boquillas (32) que están en comunicación con la unidad generadora de gas (14) y la cámara de mezclado (28) para dirigir el gas de inflado hacia la cámara de mezclado (28) para aspirar aire ambiental a través de la entrada de aire (22) y hacia la cámara de mezclado (28) de tal forma que se cree una mezcla de aire ambiental y gas de inflado generado para la inflación de la bolsa (16). Al darse el encuentro entre el ocupante y la bolsa (16) antes de que esta se encuentre completamente inflada, se crea presión posterior en la cámara de mezclado (28) para reducir o detener del flujo de aire aspirado hacia la cámara de mezclado (28) y por lo tanto reducir la velocidad de inflado de la bolsa (16),

Description

SUCTION UPO INFLATION DEVICE FOR AIR BAG BACKGROUND OF THE INVENTION The invention relates to an inflation device for an airbag and, more particularly, to an aspiration-type inflation device for an airbag that reduces the rate of inflation of the airbag in the airbag. if an occupant of a vehicle is hit with the airbag before it is completely inflated. In a typical automobile collision, inflation of the airbag is carried out in its entirety essentially at the moment when an occupant moves forward, starting from an appropriate sitting position, and comes into contact with the airbag. inflated In this case, the occupant moving forward comes in contact with the surface of the bag at approximately the speed the vehicle was carrying just before the vehicle was moving. The occupant that is moving towards the bag is wrapped and is returned to the point of rest due to the cushioning effect of the pressurized bag. However, an occupant who is not in the correct position, sitting back on the seat, but leaning forward or sitting forward or standing on the front of the seat or in contact with the cover of the airbag module At the moment the vehicle is hit, it can interfere with the airbag during the inflation process. In this case, the surface of the bag is expanding and developing back and into the interior of the vehicle at a high speed relative to that of the vehicle. The bag intercepts the occupant who is moving forward in the aforementioned manner, producing a relative impact velocity of up to 200 mph (miles per hour) with the impact surface of the occupant's bag. The partially inflated bag that continues to expand envelops the occupant, bringing the occupant to the rest position in relation to the vehicle and then, as the bag continues to pressurize, accelerates the portion of the occupant's body that is in contact with the bag rearwardly. substantial force, which can result in serious or fatal damage to the occupant. Therefore, a need has arisen for an inflation device for the airbag that automatically measures the inflation rate of the airbag in order to limit the pressure developing in the airbag, to a necessary level for the protection of the occupant, regardless of the proximity to the module for the airbag in the vehicle at the moment of impact of the vehicle.

SUMMARY OF THE INVENTION The air bag inflation apparatus of the present invention extracts air from the passenger vehicle compartment to increase the primary propellant gas that flows into the air bag during its inflation process. The air bag is inflated in this way to its normal unrestricted volume. Because an occupant that is placed in a correct position comes in contact with the airbag after it has reached its full inflation point, occupant protection is provided in a manner equivalent to that provided by the inflation mechanisms of air bags that are currently used. However, due to the limited pressure capacity of pumping intrinsic to the principles of operation of the suction mechanisms, principles that are incorporated in this invention, an anticipated encounter between the airbag that is inflating and the occupant that is outside. of the correct position will cause the inflation apparatus to mediate the flow of the gas that is entering the air pocket. The pressure in the bag, therefore, will not exceed the design pressure of the fully inflated airbag, and will remain essentially constant at design value for the remainder of the crash event, preventing serious damage or death of the occupant who was in the wrong position, a consequence that can result from the continuous pressurization of the airbag and the violent push to the occupant backwards and towards the back of the vehicle. This is achieved by using the impetus of a high-speed jet of propellant combustion products to produce and collect ambient air from the occupant compartment of the vehicle such that a mixture of aspirated air and combustion gas fills the airbag. As previously stated, the airbag will be fully inflated before coming into contact with an occupant who is properly seated before the impact of the vehicle collision. However, if the occupant is in a position too close to the airbag module at the time of the crash, the occupant will interfere with the airbag at the time it is leaving and will encounter the airbag. before it has completely inflated. The airbag does not have the capacity to expand to its total volume and the pressure in the restricted airbag will increase prematurely approaching the pressure of the final inflation design. The airbag inflation apparatus of this invention will mediate the flow of gas in the airbag by reducing or stopping the aspiration in response to the anticipated increase in pressure in the bag, thus avoiding the serious damage that the occupant may suffer. It is in an incorrect position because of the overpressurization of the bag that is being deployed. The air intakes for the aspirated air can be provided by check valves to prevent the return flow of the propellant combustion products that are inside, resulting in a reduced flow into the combustion product air bag not aspirated only. Alternatively, the air intake flow can be completely stopped if the air inlets do not have check valves, resulting in return flow of the propellant combustion gases through the air inlets.

BRIEF DESCRIPTION OF THE DRAWINGS. Figure 1 is a perspective view of a first embodiment of the air bag inflation apparatus of the present invention, after deployment of the air bag; Figure 2 is a perspective view of a portion of the air bag inflation apparatus shown in Figure 1 in a closed position prior to inflation of the air bag; Figure 3 is a perspective view of the apparatus shown in Figure 2 in an open position during and after inflation of the airbag; Figure 4 is a perspective view of the apparatus shown in Figure 3, with parts that have been separated; Figure 5 is a perspective view similar to that shown in Figure 4, showing a modified arrangement of the combustion gas nozzles; Figure 6 is a perspective view of a second embodiment of the airbag inflation apparatus of the present invention, showing modified suction, a diffusion and mixing unit in a closed position prior to inflation of the airbag; Y Figure 7 is a perspective view of the apparatus shown in Figure 6 in an open position during and after inflation of the airbag.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to Figure 1, the air bag inflation apparatus 10 of the present invention generally comprises a suction unit 12, a gas generating unit 1 4 connected to one end of the suction unit, and an inflatable airbag 1 6 connected to the other end of the suction unit. The gas generating unit 1 4 can be made with any suitable type of construction and preferably comprises a load of solid propellant (not shown) of any suitable composition that is flammable upon impact of a predetermined vehicle in the manner well known to those skilled in the art. experts in the field. Alternatively, the gas generating unit may comprise a single inert gas compressed or in combination with a propellant in a hybrid construction. Similarly, the air bag 1 6 can be of any suitable construction and be formed of any correct material. The suction unit 1 2 is shown in an open position where the air bag 1 6 is deployed in a manner that will be explained in more detail below. Before deployment, the air bag 1 6 can be stored inside or outside the suction unit 1 2. A first embodiment of the suction unit 1 2 is shown in Figures 2-5. In Figure 2, the suction unit is shown in a closed position where the air bag 1 6 can be stored inside or outside the aforementioned unit. The storage position of the airbag will depend on the construction of the suction unit 1 2 and the available space in the vehicle for the air bag inflation apparatus 10. The suction unit 1 2 preferably comprises a pair of telescopically connected plug-in telescopic sections 18 and 20. The outer section 18 can be moved between the closed position shown in Figure 2, where it covers the inner section 20, and the open position shown in Figure 3, where leaves a variety of air inlets 22 exposed in the inner section. The opposite or external end of the outer section 18 comprises a pair of diffuser vanes 24, which, in one of the embodiments, can be tilted in any suitable way to have their closed position as shown in Figure 2, where they are overlapped one to another by a hinge mechanism 26 or some other similar mechanism that is suitable. In this embodiment, the air bag 1 6 is stored on the outside of the suction unit as shown with solid lines in Figure 2. In another embodiment of the invention, the diffuser vanes 24 can be stored internally. of the suction unit as shown with the dotted lines of Figure 2, where said diffuser fins would be inclined inwards and where each would have an approximate width of half the height of the aspiration unit at the outer end of the same. In this embodiment of the invention, the air bag 1 6 is stored within the suction unit as shown by dotted lines in Figure 2. As shown in Figure 4, the external suction section 18 defines a chamber mixed 28, and the internal suction section 20 comprising a variety of air inlets 22 on the upper and lower sides thereof, which are separated by a wall 30 comprising a plurality of movable gas nozzles 32 that are in communication with the gas generating unit 1 4. Each of the air inlets 22 can be opened or closed to the air flow by a butterfly valve 36 or any other suitable valve mechanism that is inclined by some suitable hinged mechanism 38 or some another similar to the closed position shown in Figure 4, where you close the air intake, and can move to the open position shown in Figure 3, in a way that will be explained in more detail later. The air inlets 22 are separated by partitions 40 extending up and down from the wall 30. In one embodiment of the invention, each of the air inlets 22 has an inwardly inclined surface 34 with which it engages with the valve 36 when in the open position of Figure 3. In another embodiment, instead of the inwardly inclined surface 34, the butterfly valve 36 is formed with a curved shape suitably to provide the inclined surface of air intake when in the open position.An alternative embodiment of the invention for the suction unit 12 is shown in Figure 5, where a larger number of mobile nozzles for gas of smaller size 32a are provided, which are in aligned form along the internal surfaces of the divisions. 40. The nozzles 32a are in communication with the gas generating unit 1 4. The number, size and arrangement of the mobile gas nozzles 32 and 32a will determine the size of the mixing section 28 of the external aspiration section 18 according to with well-known principles for those experts in the field. In the operation of the air bag inflation apparatus of the present invention, when the apparatus is in an inactive state in the vehicle with the air bag stored inside or outside the external suction section 18, the external suction section 18 covers the inner section 20 and closes the air inlets 22, as shown in Figure 2. In this position, the diffuser vanes 24 are bent and closed as shown in the embodiment of the invention with solid lines in Figure 2 The air bag 1 6 is externally attached to the suction unit 12 as shown in Figure 1. The air bag is then folded and secured in place against the diffuser flaps according to methods known to those skilled in the art.

In the second embodiment of the invention shown with dotted lines in Figure 2, diffuser vanes 24 and air bag 1 6, are stored inside the suction unit 1 2 in the external section 18 thereof. Upon predetermined impact to the vehicle, the gas generating unit 14 is activated to generate gases which are directed towards the mixing section 28 of the external suction section 18 through the mobile gas nozzles 32 or 32a. The accumulated pressure of the moving gas within the mixing section 28 opens the diffuser flaps 24, unrolls the air bag 1 6, and causes the external suction section to move towards the open position shown in Figure 3, where exposes the air inlets 22 in the internal suction section 20 and creates a pressure differential which in turn opens the butterfly valves 36 and allows ambient air to be sucked through the air inlets 22 and into the mixing chamber 28 of the movable suction section 18. During the initial flow of mobile gas into the mixing chamber 28, the butterfly valves 36 are in the closed position as shown in Figure 4 to prevent the mobile gas from flowing backward and out through the air inlets 22. The pressure build-up in the mixing chamber 28 of the external suction section 18 caused by the mobile gas generated and the sucked air inflates the bag of air in the manner shown in Figure 1. Suitable stop mechanisms (not shown) are provided to limit the movement of the external suction section 18 relative to the internal section 20. Also, the movement of the diffuser vanes 24 toward the open position shown in the Figure 3 is limited by hinge mechanisms 26 or any other suitable stop mechanism such that the diffuser flaps are at the desired angle in accordance with the principles that are well known in the art by those skilled in the art. The diffusion fins 24 are opened either mechanically by belts (not shown) attached to the air bag 1 6 or pneumatically by the gases coming from the gas generator 1 4. The fins are maintained at the correct half-angle by the internal pressure of gas. Either the airbag or the structure for the vehicle mounted serve as divisions on each side of the diffuser fins, ensuring that there is only axial flow. In the normal operation of the air bag inflation apparatus 10, the air bag 1 6 would be fully inflated before the occupant comes into contact with it. However, if an occupant is out of position and comes into contact with the air bag 1 6 before it is fully inflated, a subsequent pressure will be created through the restricted air bag in the mixing chamber 28 which will prevent aspiration as the subsequent pressure increases; the butterfly valves 36 will be closed avoiding the return flow of the generated mobile gas, consequently reducing the inflating speed of the airbag and avoiding serious damage to the occupant. Because the pressure of the bag increases to exceed the pump pressure limit of the vacuum cleaner, the butterfly valves 36 close preventing the return flow of the propellant gases out of the air inlets 22 and allowing the same to continue filling the airbag at the reduced inflation rate. Alternatively, butterfly valves 36 or other types of check valves can be omitted from the air inlets, in which case the back pressure created by the encounter between the occupant that is out of the correct position with the air bag Partially inflated can cause a return flow from the mixing chamber to the air inlets 22 to stop further inflation of the air bag and prevent serious damage to the occupant. If the butterfly valves 36 or other valves in the air inlets 22 are not used, the moving gas nozzles and the mixing chamber would be constructed in accordance with principles that are well known to those skilled in the art to ensure that the mobile gas created by the gas generating unit 1 4 creates sufficient pressure in the mixing chamber 28 to move the external suction section 1 8 to the open position without having a significant flow of mobile gas through the inlets of air 22. Figures 6 and 7 illustrate a further embodiment of the present invention where the suction unit 1 00 comprises a pair of telescopic sections 1 18 and 1 20, where the outer section 1 18 is movable and goes from the closed position shown in Figure 6 to the open position shown in Figure 7, where the air inlets 1 22 are exposed in the internal section 1 20. The construction of the inter section 1 of suction 1 20 is essentially the same as that of the internal suction section 20 shown in Figures 3-5. The construction of the external mobile suction section 1 1 8 differs from the suction section 18 shown in Figures 2 and 3 in that the former does not comprise the diffuser vanes 24 which are normally closed. In contrast, the external suction section 1 1 8 comprises diffuser vanes 1 24 which are open both in the closed and open positions of the external suction section, and also have divisions on each side of the diffuser vanes to ensure the axial flow. In an embodiment of the invention, the diffuser flaps 1 24 are fixed at the desired angle for adequate inflation of the air bag. In another embodiment of the invention, for purposes of limiting the storage height of the suction unit, the diffuser vanes 124 can be moved from a first position, as shown in Figure 6, where they are disposed substantially in the same plane as the upper and lower adjacent surfaces of the suction section 1 18, and can move to a second position, as shown in Figure 7, through hinge means 126 or some other similar to the desired angle when the suction section 1 18 moves to the open position shown in Figure 7 during inflation of the airbag. To prevent any leakage of the air and the gas mixture inflating the airbag, the suction unit 1 18 may be provided with slidable side wall sections 1 27 which are fixed to the diffuser flaps 1 24 and moving outwards, as shown in Figure 7. In another embodiment of the present invention, for the purpose of conserving space when in the closed position, the mobile external suction section 1 18 could be formed by two telescopic sections, a mixing section 1 18a and a diffusing section 1 18b which can be slid over the mixing section 1a within a telescopic relationship with each other. This embodiment of the invention is shown schematically with dashed lines in Figures 6 and 7. Although some of the preferred embodiments of this invention have been described earlier in the document as mere examples, those skilled in the art will understand that modifications to the disclosed embodiments may be made without departing from the scope of the invention, which is described in the appended claims.

Claims (15)

1. Having described the invention, it is considered as a novelty, for which the content is claimed in the following CLAIMS 1. An apparatus for inflating an airbag of a vehicle and for reducing the inflation rate of the airbag in the event that a vehicle occupant encounters the airbag before it has been fully inflated, that comprises: means for generating gas to produce an inflation gas in response to a predetermined impact for the vehicle, suction means operatively connected to said gas generating means and to the air bag, said suction means comprising an inlet for ambient air, a mixing chamber that is in communication with said air inlet, a nozzle means that is in communication with said gas generating means and wherein said mixing chamber for directing the inflating gas to said mixing chamber to suck the ambient air through said air inlet into said mixing chamber, in order to generate a mixture of ambient air and gas generated from inflation to inflate the airbag, where upon contacting the vehicle occupant and the airbag before it is fully inflated, a subsequent pressure is created in said mixing chamber to reduce the air flow sucked into said mixing chamber and reduce the rate of inflation of the airbag, thus avoiding the continuous and rapid inflation of the airbag possible and serious damage to the occupant. The apparatus of claim 1, wherein said suction means is connected to one end of said gas generating means and to the other end to the air bag. The apparatus of claim 1, wherein said suction means comprises a plurality of ambient air inlets and wherein said nozzle means comprise a plurality of nozzles. The apparatus of claim 1, wherein said suction means comprises an internal section and an outer section in telescopic relation with said internal section, wherein said internal section is connected to said gas generating means and includes said air inlet. environmental and said nozzle means, and wherein said external section includes said mixing chamber which is in turn connected to the air bag, wherein said external section is movable by means of inflation gas and ambient air pressure in said chamber. mixed from a closed position, where it covers the ambient air inlet in said internal section, to an open position where it leaves exposed the ambient air inlet in said internal section. The apparatus of claim 4, wherein said air inlet comprises means of check valves operating to normally close said air inlet and to open when there is suction of air through said air inlet, where said valve means The retention device can be operated to close said air inlet when a subsequent pressure is created in said mixing chamber. The apparatus of claim 1, wherein said suction means comprises diffusion means arranged adjacent to said air bag to increase the pressure of the mixture of aspirated air and inflation gas generated at the pressure required to inflate the bag of air. The apparatus of claim 6, wherein said diffusion means comprises a pair of diffuser fins that are normally inclined to a closed position to interrupt communication between said mixing chamber and the air bag, said fins being movable diffusers to be placed in open position when there is an increase in the pressure of the inflation gas and the ambient air in said mixing chamber. The apparatus of claim 6, wherein said diffusion means comprises a pair of diffuser flaps that are normally inclined toward a non-operative position disposed within said mixing chamber and can be moved to an open position outside of said chamber. mixed, when there is an increase in the pressure of the ambient air and the inflation gas inside the chamber. The apparatus of claim 7, wherein said diffuser flaps are connected to the air bag. The apparatus of claim 8, wherein said diffuser flaps are connected to the air bag. eleven . The apparatus of claim 4, wherein said internal suction section comprises a plurality of air inlets disposed on opposite sides of the section, wherein said air inlets are separated by walls having nozzle means there disposed. 12. The apparatus of claim 1, wherein said suction section further comprises dividing means separating said air inlets, having said nozzle means included. The apparatus of claim 4, wherein said external suction section comprises a mixing section including said mixing chamber and a diffusing section mounted in telescopic relation in said mixing section. The apparatus of claim 5, wherein said air inlet has a surface that is inclined inwardly and towards said mixing chamber, and wherein said check valve comprises a butterfly valve mounted by hinge on said inclined surface. 15. The apparatus of claim 5, wherein said check valve comprises a butterfly valve mounted by hinge in said air inlet.