DE10021845A1 - Dual airbag system for restraint in case of frontal collision; has thorax and head airbags connected to each other and gas generator and has tactile bag provided in thorax airbag to detect obstacle - Google Patents

Abstract

The system has two front airbags assigned to a vehicle occupant. In the expanded state, the airbags are supported longitudinally along the vehicle shell and form a common restraint system. One of the airbags is a thorax (1) airbag, which is connected to a head airbag (2). The head airbag expands between the front plate (6) of the dashboard (4) unit and a part of the thorax airbag. A tactile bag (13) is provided in the thorax airbag to detect an object in the expansion zone. The airbags are expanded by gas from at least one gas generator (7) in the direction of the expansion zone and are controlled according to a tactile path between the gas flow and an obstacle. The airbags are connected to each other and to the gas generator by a filling channel (8). An Independent claim is included for a dual airbag system with at least one gas generator and two airbags.

Description

The invention relates to a dual airbag system as a restraint in a frontal impact, in particular for arrangement in the dashboard in the area of the passenger seat in one Motor vehicle.

Airbag devices in motor vehicles with several front airbags are in the various embodiments and known for a variety of crash situations. DE 196 26 903 A1, for example, relates to an airbag device in which the Gas generator is arranged as a cartridge in the cross member in the area of the dashboard. The cross member is in the area of the cartridge with openings to one or more Airbag containers provided, which are arranged directly on the cross member. DE 198 09 428 A1 also describes a safety device for a motor vehicle, in which at least the Gas generators with the airbags arranged in the front area of the passenger compartment Operational connection, arranged in the cross member and each with a gas line part the diffuser of the associated airbag holder are connected.

With the unpublished DE 198 60 827 is a restraint system for one Frontal impact with one held on the vehicle roof and in the activated state an airbag deploying vehicle occupants, which has a head part and a thorax part, can be unfolded forwards / downwards, and each part in the unfolded state with a partial area in the vehicle longitudinal direction on the vehicle body, in particular also the dashboard, is supported. Alternatively, the airbag is a head airbag trained and deployable forward / downward and forms with another airbag, a thorax airbag deploying from the dashboard, a restraint system, both Airbags are supported on the vehicle body in the longitudinal direction of the vehicle. The Airbags deployed independently of each other and are each with a separate one Gas generator coupled. They have to be brought to an appropriate volume, so that they interact with each other and fulfill their retention function can. Associated with this is an increased impairment of an OOP (out of position) vehicle occupants located when the restraint system is activated.  

Part of the airbag devices can be sensor systems that trigger the Deployment of the airbag or airbags in relation to the seating position of the occupant to be protected Measure for the respective airbag and the time and from the result of these measurements derive the extent of airbag deployment. DE 44 20 114 A1 has an airbag device for the front and side protection, where a trigger device is used Control electronics is arranged, but the direction and intensity of an impact also the seat occupancy is recorded and the airbags individually depending on the signals or triggers in combination. It is also known to use pressure relief valves that are operatively connected to a seat occupancy sensor system via a control device in order to the gas flow for the airbag depending on the seating position of a vehicle occupant to control, especially to decrease if the vehicle occupant in the event of an impact not in its predetermined sitting position, but in the bent-over position - OOP or there is even a child in the keep out zone of the airbag so that the Airbag does not affect vehicle occupants with full gas pressure. Furthermore, it is known, step generators for controlling the gas mass flow in an airbag and to use the gas pressure in it.

In the event of a complex accident, the vehicle occupants over the duration of the To be able to protect the vehicle from the first impact even in the event of a secondary impact is in DE 92 11 421 U1 a gas bag restraint system with at least two chambers gas bag has been proposed, of which the first, larger chamber the surrounds the second and is delimited by a wall, the material of which is larger Has gas permeability as the material delimiting the second chamber. The first Chamber protects the vehicle occupant in the primary impact, but then falls quickly together, while the second, inner chamber remains filled so long that it too forms a protective gas cushion even in the event of a secondary impact.

It is an object of the invention to use a dual airbag system as a restraining device To design frontal impact according to the preamble of claim 1 so that the Protection potential for a vehicle occupant is significant regardless of their seating position is increased and the gas mass flow into the thorax airbag to reduce it Aggressiveness is controlled by mechanical means.

This object is achieved in an airbag device according to the preamble of claim 1 solved by its characteristic features. Advantageous configurations are in the Subclaims listed.  

The invention is that in a dual airbag system with two one Front airbags assigned to vehicle occupants, which in the unfolded state with a Subarea in the vehicle longitudinal direction are supported on the vehicle body and together form or form a restraint system and one of which serves as a thorax airbag, this thorax airbag is operatively connected to a separately inflatable head airbag that between the vehicle body, in particular with respect to the front window at a Passenger airbag, and a portion of the thorax airbag is arranged and at the same time as Support airbag for this is used, the two airbags with each other and a filling channel are connected to at least one gas generator, and that in the thorax airbag Touch element is integrated as a detection means for an obstacle in the deployment zone, the is activated by gas released by the gas generator in the direction of the deployment zone and as a function of the tactile path determined by hitting the obstacle controls the gas flow into the thorax airbag and thus its deployment, taking the tactile path shortened by the impact of the sensing element on the obstacle and the gas flow in the Thorax airbag is prevented or delayed.

Instead of the conventional thorax airbag, there are now two airbags in the vehicle's longitudinal direction arranged one behind the other, of which the head airbag supporting the head of the Serves vehicle occupants and the thorax airbag and even compared to the vehicle body, is supported in particular in relation to the front window in a passenger airbag, which provides a very effective restraint system. They are two separate ones Gas flows formed, and it stands for the total gas volume available for the Chest airbag deployment less gas is available per unit of time, causing deployment of the thorax airbag is inevitably less aggressive than an OOP Vehicle occupant is. In addition, the aggressiveness of the thorax airbag is caused by the Arrangement of the probe element significantly reduced, since this is in an OOP Vehicle occupants prevented or delayed complete deployment of the thorax airbag. At In contrast, a thorax airbag deploys to a vehicle occupant in position instantaneously and the head airbag simultaneously with this or, depending on the version of the Systems, delayed compared to this.

In a preferred embodiment, the thorax airbag and the head airbag are each in arranged in a separate chamber, the gas generator being in view of Interacting with the sensing element housed in the chamber with the thorax airbag and is arranged concentrically in the filling channel. The one that houses the thorax airbag the chamber facing the vehicle occupant can easily move towards the horizontal be inclined downwards in order to ensure that the thorax airbag deploys on one  OOP vehicle occupants or slide down on a child seat and thus can dodge. The head airbag is designed and arranged expediently so that this unfolds on the thorax airbag in order to Restraint and support function can be better met. With regard to an OOP vehicle occupants can delay the inflation of the head airbag opposite the thorax airbag.

The gas generator with its diffuser is expediently in the filling channel arranged essentially in the longitudinal direction of the vehicle and can be of one with the probe element connected sliding sleeve to be surrounded by released gas in the direction of Passenger compartment is acted upon and movable. The sliding sleeve determines in Depends on their position on the gas generator and thus on the diffuser per unit of time amount of gas released. Your displacement can be done easily by a stop be limited, which may also be used as an electrical contact to ignite a provided second generator stage can be formed. The tactile element is preferably a tactile bag which can be acted upon via the sliding sleeve and which can be unfolded via the latter is and in the activated state in turn the sliding sleeve in the direction of Deployment zone shifts, with the thorax airbag resting against the touchbag on the passenger compartment side.

Both the tactile bag and the head airbag can be at a cross to the vehicle longitudinal direction trained gas distribution device can be arranged so that the respective airbag over the widest possible area can be unfolded evenly. The gas distribution devices advantageously have baffles for the gas flow.

The thorax airbag can also help further reduce its aggressiveness towards its deployment zone, conveniently right next to the Tastbag, with Tear tapes. If there is no obstacle in the development zone, the Tastbag is not hindered in its development, the sliding sleeve gives the diffuser The gas generator is largely free, and the thorax airbag passes the tactile bag initially unfolded essentially in the radial direction. If a certain pressure in the Thorax airbag is reached, the tear strips tear and the thorax airbag deploys, now also in the axial direction, completely.

To delay the deployment of the head airbag can be in front of the head airbag in the filling channel assigned a controllable valve or a pressure relief valve his. This can also be done in a on the filling channel between the gas generator and the  Gas distribution channel trained and serving as a gas collection chamber be arranged, which may alternatively consist of an elastic material. At When the system is activated, released gas flows through the filling channel into the antechamber and when a certain gas pressure is reached via the valve in the gas distribution channel and the head airbag.

The above-described dual airbag system can be used by an appropriate Airbag material can also be designed as a closed gas system in which the released Gas largely remains. The thorax airbag and / or the head airbag have elasticity unfoldable areas for the formation of refill chambers. In the event of a crash, the in the deployed thorax airbag presses gas from the thorax airbag the head airbag and the elastic areas are pressed to form the refill chambers. At the Detaching the vehicle occupant from the thorax airbag after the impact presses it elastically expanded refill chambers, the gas in them is returned to the thorax airbag or the head airbag back where it is ready for restraint for a secondary collision and in connection with gas flowing slightly from the gas generator - for example by igniting a further generator stage - for a sufficient one Gas pressure ensures that the vehicle occupant does not have to inflate again is charged additionally, not even in OOP. The whole head airbag can be used as Refill airbag designed. To accelerate the gas flow between the The thorax airbag and the head airbag can be located between the gas distribution devices of the two airbags flexible connection channels can be arranged parallel to the filling channel.

So that the hands of the vehicle occupant, who is supported in a crash, unfold of the thorax airbag does not hinder the deployment of the tactile and / or thorax airbag preferably provided in a substantially radial direction so that the hands be raised. By coordinating axial and radial gas flows at the diffuser of the Thorax airbags and on the sliding sleeve in connection with the controllable Distributor valve in the filling channel is a reduction in the load on the vehicle occupant given undiminished protection potential.

The gas generator used can be an n-stage gas generator with a predetermined one or controllable Δt. The head airbag can also be equipped with a separate gas generator be coupled and deployed to the thorax airbag with a time delay. The respective Δt can depend on the severity of the accident, the sitting position and the Passenger weight can be variable. Because the airbags are filled at different times, this can happen  Protection potential for an OOP passenger in a primary and also in one Secondary impact can be optimized.

The gas generator and the chambers connected to it are preferred each housed airbag combined into a multibag module, which is separate from the Vehicle can be preassembled into a structural unit and as such in one on the vehicle body or the cavity designed for the vehicle equipment can be introduced and mounted there. The components of this module can be integrated in a foam body, which is adapted to the shape and size of the cavity, so that the cavity wall forms a fixed bearing for the module. A multibag module assigned to the front passenger for example, is conveniently located in the glove compartment of the vehicle, the gas generator being arranged in the Y direction and thus parallel to the central tube. The chamber housing the head airbag and the diffuser assigned to it is included so arranged that it opens into the area of the dashboard near the windshield, so that the head airbag from there into the vehicle interior onto the head area of the Vehicle occupants and the thorax airbag unfolds and supports them. The works Head airbag also in the case of a pedestrian hitting the windscreen Support for this. Finally, the head airbag can be designed so that this over the entire windscreen width can be unfolded and additionally supports the steering wheel airbag, and also in such a way that it covers the entire height of the windscreen and thus at one Rollover secures the entire windscreen area so that the vehicle occupants or the body parts of which are retained in the passenger compartment.

The dual airbag system described above can by a below the Thorax airbags arranged knee airbag can be supplemented. This is in one with the same Gas generator - in the extended system an n-stage generator - connected separate chamber and arranged so that both airbags unfolded in the Support condition against each other. The knee airbag is not just one is a further protective measure for the vehicle occupant, but also stabilizes it entire restraint system.

It should be noted that the gas generator with a from the chamber for the thorax airbag in the engine compartment or blow-off line leading directly to the outside and one through the Tastbag can be connected to a controllable valve which allows it to be operated at an extremely high level OOP vehicle occupants do not release the gas after stopping the tactile bag Thorax airbag, but to blow outside, so that the thorax airbag largely  remains unfolded. However, with such a design, the blown gas goes for lost a secondary impact.

The invention is explained below using an exemplary embodiment. In the associated drawings show schematically:

Fig. 1 is a side view of an object placed on the passenger side of the instrument panel in the dual airbag system deployed airbag,

Fig. 2 shows the dual airbag system in an enlarged view

Fig. 3 is a plan view of this.

The dual airbag system shown in FIG. 1 and in FIG. 2 has two front airbags assigned to a passenger, a thorax airbag 1 and a head airbag 2 , which are shown in the deployed state and are supported in each case with a partial area on the vehicle body. The thorax airbag 1 is arranged in a chamber 3 in the control panel 4 and is supported on it in the deployed state. The head airbag 2 , with which the thorax airbag 1 is operatively connected, is accommodated in a chamber 5 and, in the deployed state, is supported on the front window 6 , the head airbag 2 deploying in the space between the thorax airbag 1 and the front window 6 when activated . Both front airbags ( 1 , 2 ) are coupled to a common gas generator 7 , which is accommodated in the control panel 4 in the chamber 3 with the thorax airbag 1 and there concentrically in a filling channel 8 which is connected to the head airbag 2 via a prechamber 9 , pressure relief valves 10 and 11 and a gas distribution channel 12 arranged transversely to the longitudinal direction of the vehicle.

A tactile bag 13 is integrated in the thorax airbag 1 and is coupled to a sliding sleeve 15 surrounding the gas generator 7 via a gas distributor pipe 14 arranged transversely to the longitudinal direction of the vehicle. The gas generator 7 is provided with a pressure relief valve 16 on the side facing away from the sliding sleeve 15 . The sliding sleeve 15 has a collar 17 which is in operative connection with a collar 18 formed on the filling channel 8 as a stop on the touch-bag side and limits its displacement. The thorax air bag 1 its deployment disabling tear strips 19 are arranged in the illustrations in FIGS. 1 and 2 have already been torn with the fully deployed thorax airbag 1. The chamber 3 for the thorax airbag 1 is inclined downwards by 5 ° with respect to the horizontal, so that the passenger in an OOP's position can slide down there and develop more in the leg area. In Fig. 3 it can be seen that the gas distribution pipe 14 has baffles 20 in its interior for the gas flow.

When the gas generator 7 is activated, released gas is released into the gap between the latter and the sliding sleeve 15 , which passes through openings in the end face thereof into the distributor pipe 14 and unfolds the tactile bag 13 . The sliding sleeve 15 is displaced in the direction of the passenger compartment, and gas also enters the filling channel 8 , which unfolds the thorax airbag 1 in the radial direction in an initial stage, still lying against the tactile bag 13 in the axial direction (in FIGS . 1 and 2 shown in dashed lines). If the tactile bag 13 encounters an obstacle (not shown), its further advancement and the displacement of the sliding sleeve 15 are stopped, so that it still largely surrounds the gas generator 7 and hinders the release of gas via the outer surface of the gas generator 7 into the filling channel 8 . The mass of the released gas reaches the filling channel 8 via the pressure relief valves 16 and 11 and deploys the thorax airbag 1 with a delay. From the filling channel 8 , gas also reached the pre-chamber 9 , which is connected to the pressure relief valve 10 with the gas distribution channel 12 , through which gas, delayed again, flows into the head airbag 2 and deploys it, now delayed in relation to the thorax airbag 1 . In this way, an OOP passenger is less aggressively impacted by the thorax airbag. If the front passenger is not OOP and there is no other obstacle to the advancement of the tactile bag 13 , the sliding sleeve is displaced by this with its collar 17 to the collar 18 of the filling channel 8 , and the thorax airbag 1 unfolds without delay past the tactile bag 13 , initially in radial direction, and when a certain gas pressure is exceeded in this after tearing the tear tapes 19 in the axial direction towards the passenger. In this case too, the head airbag 2 is deployed with a delay relative to the thorax airbag 1 via the prechamber 9 and the pressure relief valve 10 located therein.

REFERENCE SIGN LIST

1

Thorax airbag

2

Head airbag

3rd

chamber

4

Switchboard

5

chamber

6

Windscreen

7

Gas generator

8th

Filling channel

9

Antechamber

10th

Pressure relief valve

11

Pressure relief valve

12th

Gas distribution channel

13

Tastbag

14

Gas distribution pipe

15

Sliding sleeve

16

Pressure relief valve

17th

Federation

18th

Federation

19th

Tear tape

20th

Baffle

Claims (19)

1. Dual airbag system as a restraint device in a frontal impact with two front airbags assigned to a vehicle occupant, which are supported in the deployed state with a portion in the longitudinal direction of the vehicle body and together form or form a restraint system, and one of which serves as a thorax airbag, characterized in that the thorax airbag ( 1 ) is in operative connection with a head airbag ( 2 ), which can be deployed between the vehicle body (front window 6 ) and a portion of the thorax airbag ( 1 ), that in the thorax airbag ( 1 ) a sensing element ( 13 ) as a detection means for an obstacle in the Deployment zone is integrated, which is activated by gas released by at least one gas generator ( 7 ) in the direction of the deployment zone and controls the gas flow into the thorax airbag ( 1 ) depending on the tactile path determined by hitting an obstacle, the thorax airbag ( 1 ) and the head airbag ( 2 ) over one Filling channel ( 8 ) with each other and with the gas generator ( 7 ) are connected. 2. Dual airbag system according to claim 1, characterized in that the thorax airbag ( 1 ) and the head airbag ( 2 ) are each arranged in a separate chamber ( 3 , 5 ) and the gas generator ( 7 ) in the chamber ( 3 ) with the thorax airbag ( 1 ) is housed and arranged concentrically in the filling channel ( 8 ). 3. Dual airbag system according to claim 1 or 2, characterized in that the thorax airbag ( 1 ) accommodating and directed to the vehicle occupant chamber ( 3 ) is inclined slightly downwards relative to the horizontal, preferably by 5 to 10 °. 4. Dual airbag system according to claim 2, characterized in that the gas generator ( 7 ) in the filling channel ( 8 ) is surrounded by a pressurized by released gas sliding sleeve ( 15 ) on which the sensing element ( 13 ) is arranged or formed and which is dependent determines the amount of gas released per unit of time from its position above the gas generator ( 7 ). 5. Dual airbag system according to claim 4, characterized in that the gas generator ( 7 ) on the side facing away from the sliding sleeve ( 15 ) is provided with a pressure relief valve ( 16 ). 6. Dual airbag system according to claim 1 and 4, characterized in that the sensing element is a via the sliding sleeve ( 15 ) to which gas can be applied ( 13 ) which, in the activated state, moves the sliding sleeve ( 15 ) in the direction of the deployment zone, and that the thorax airbag ( 1 ) during the penetration of the tactile bag ( 13 ) into the deployment zone on the passenger compartment side. 7. Dual airbag system according to claim 4 or 6, characterized in that the displacement of the sliding sleeve ( 15 ) is limited by a stop ( 18 ). 8. Dual airbag system according to claim 6, characterized in that the tactile bag ( 13 ) is coupled to a gas distributor tube ( 14 ) arranged essentially transversely to the longitudinal direction of the vehicle on the sliding sleeve ( 15 ). 9. Dual airbag system according to claim 8, characterized in that the gas distributor pipe ( 14 ) is provided with baffles ( 20 ) for the gas flow. 10. Dual airbag system according to one or more of the preceding claims, characterized in that the thorax airbag ( 1 ) is provided with tear strips ( 19 ) in the direction of its deployment zone. 11. Dual airbag system according to claim 1, 2 or 4, characterized in that between the filling channel ( 8 ) and the head airbag ( 2 ) is arranged a transverse to the vehicle longitudinal gas distribution channel ( 12 ). 12. Dual airbag system according to claim 11, characterized in that a controllable distribution valve or a pressure relief valve ( 11 ) is arranged in the filling channel ( 8 ) before the gas distribution channel ( 12 ). 13. Dual airbag system according to claim 11 or 12, characterized in that the gas distribution channel ( 12 ) is provided with baffles for the gas flow. 14. Dual airbag system according to claim 11 or 13, characterized in that a prechamber ( 9 ) is arranged on the filling channel ( 8 ) between the gas generator ( 7 ) and the gas distribution channel ( 12 ), the gas distribution channel side with a controllable valve or a pressure relief valve ( 10 ) is provided. 15. Dual airbag system according to one or more of the preceding claims, characterized in that the thorax airbag ( 1 ) and / or the head airbag ( 2 ) has elastically deployable areas for forming refill chambers. 16. Dual airbag system according to claim 2, characterized in that the gas generator ( 7 ) and the chambers connected to it ( 3 , 5 ) with the respectively accommodated airbag ( 1 , 2 ) are combined to form a dual airbag module, which in one on the vehicle body or expansion trained cavity can be arranged. 17. Dual airbag system according to claim 16, characterized in that the gas generator ( 7 ) and the chambers ( 3 , 5 ) are embedded in a foam body which has the shape of the cavity. 18. Dual airbag system according to claim 16 or 17, characterized in that a passenger assigned dual airbag module is arranged in the glove compartment of the vehicle, wherein the head airbag ( 2 ) accommodating chamber ( 5 ) in the region of the front window ( 6 ) opens into the passenger compartment . 19. Dual airbag system with at least one gas generator and two airbags, characterized in that the gas generator ( 7 ), a thorax airbag ( 1 ) with an integrated tactile bag ( 13 ) and a head airbag ( 2 ) and these with the gas generator ( 7 ) connecting gas distribution devices ( 12 , 14 ) and a filling channel ( 8 ) arranged or foamed in a foam body and combined to form a preassembled dual airbag module.