JP5229205B2 - Airbag device - Google Patents

Description

  The present invention relates to an airbag device including a knee protection bag for protecting a passenger's knee.

  An airbag device is known in which an airbag for restraining a knee is connected to an airbag for restraining the upper body of an occupant (for example, see Patent Document 1). There is also known an airbag device that simultaneously inflates and deploys an airbag for restraining the upper body of an occupant and an airbag for restraining a knee by gas supply from a common pressure accumulator (for example, , See Patent Document 2).

Japanese Utility Model Publication No.7-17662 JP-A-51-23917

  By the way, since the knee protection bag arranged above the knee in the instrument panel is deployed downward from the upper side in the vehicle vertical direction, the knee protection bag is attached to the instrument panel and the occupant's knee. There is room for improvement with regards to successful development between the two.

  An object of the present invention is to provide an airbag device that can satisfactorily deploy a knee protection bag disposed above a knee in an instrument panel between the instrument panel and an occupant's knee. It is.

The airbag apparatus according to the first aspect of the present invention is folded on the upper side in the vehicle vertical direction from the occupant's knee in the instrument panel, and receives the gas supply and faces downward in the vehicle vertical direction on the vehicle compartment side with respect to the instrument panel. An upper bag that is unfolded, a lower bag that is folded so as to be positioned on the instrument panel side with respect to the upper bag in the unfolding process, and roll-folded so as to be inward in the folded state, and the roll-folded state The lower bag is sewn to the upper bag with a tear seam, and the folded state of the lower bag with respect to the upper bag is maintained, and the maintained state is maintained by the deployment pressure of the lower bag due to gas supply through the upper bag. A knee protection bag having a folded holding means to be eliminated, and the knee protection bag And a, a gas supply device for supplying a gas into the bag.

  In the airbag device according to claim 1, for example, when gas is supplied from the gas supply device to the upper bag of the knee protection bag at the time of a frontal collision of the vehicle, the upper bag is first instrumented by the gas from the inflator. It expands and deploys downward on the vehicle compartment side of the panel. When the lower bag is supplied with gas through the upper bag from the folded state toward the instrument panel with respect to the upper bag by the folded holding means, the holding by the folded holding means is canceled by the developed pressure. Then, the lower bag, which is rolled inward, is expanded and deployed while the roll folding is canceled so as to roll along the instrument panel. Thereby, the lower bag of the knee protection bag is easily deployed along the instrument panel, and is deployed so as to be embedded between the instrument panel and the occupant's knee.

  Thus, in the airbag device according to claim 1, the knee protection bag disposed above the knee in the instrument panel is preferably deployed between the instrument panel and the occupant's knee. Can do.

Moreover, in this airbag apparatus, since the folding | returning holding means is comprised by sewing to the upper bag of the lower bag by a tear seam, the reliability of bag expansion | deployment control is high.

Airbag apparatus according to the second aspect of the present invention, in the airbag device according to claim 1 Symbol mounting, the expansion at the cabin side with respect to the instrument panel by receiving a supply of gas from said gas supply device, to be deployed The upper body protection bag for restraining the upper body of the vehicle occupant from the front side in the vehicle front-rear direction is folded together with the knee protection bag.

In the airbag device according to the second aspect , for example, when gas is supplied from the gas supply device at the time of a frontal collision of the vehicle, the knee protection bag and the upper body protection bag are inflated and deployed, respectively. Thus, the knee protection bag folded together with the upper body protection bag is deployed downward from above the occupant's knee. Here, since the lower bag is deployed along the instrument panel after the upper bag is deployed as described above, the lower bag, which is the knee restraint portion of the knee protection bag, is placed between the instrument panel and the occupant's knee. It is developed to dive in. That is, in this airbag apparatus, the knee protection bag folded together with the upper body protection bag can be satisfactorily deployed between the instrument panel and the occupant's knee.

  As described above, the airbag device according to the present invention allows the knee protection bag disposed above the knee in the instrument panel to be satisfactorily deployed between the instrument panel and the occupant's knee. It has an excellent effect of being able to.

It is a sectional side view which shows the deployment state of the airbag in the airbag apparatus which concerns on embodiment of this invention. It is side sectional drawing which expands and shows the airbag which comprises the airbag apparatus which concerns on embodiment of this invention. It is a back sectional view showing the deployment state of the airbag in the airbag device concerning the embodiment of the present invention. It is a sectional side view which shows the expansion | deployment process of the airbag in the airbag apparatus which concerns on embodiment of this invention. It is a sectional side view which shows the initial stage of expansion | deployment of the subbag which comprises the airbag apparatus which concerns on embodiment of this invention. FIG. 6 is a side sectional view showing a tearing state of a tear seam in a deployment process of a sub-bag constituting the airbag device according to the embodiment of the present invention. It is a side sectional view showing the state where the lower roll folding is canceled, in the deployment process of the subbag which constitutes the airbag apparatus according to the embodiment of the present invention. It is a sectional side view which shows the deployment completion state of the subbag which comprises the airbag apparatus which concerns on embodiment of this invention.

  A passenger seat airbag apparatus 10 as an airbag apparatus according to an embodiment of the present invention will be described with reference to FIGS. First, the overall configuration of the passenger airbag device 10 will be described, and then the folding structure of the subbag 28 will be described. In addition, arrow FR, arrow UP, and arrow W appropriately described in each figure respectively indicate the vehicle V to which the passenger seat airbag device 10 is applied, the vehicle front direction (traveling direction), the upward direction, and the vehicle width direction of the passenger seat 12. Is shown. Further, in the following description, when the shape of the airbag 20 (its constituent part) is described, the shape in the inflated and deployed state is referred to unless otherwise specified.

(Overall configuration of passenger airbag device)
FIG. 1 is a schematic side cross-sectional view of a front portion in a passenger compartment C of an automobile V in an operating state of a passenger seat airbag device 10. As shown in this figure, a passenger seat 12 as a vehicle seat is disposed in the front part of the passenger compartment C. The passenger seat 12 includes a seat cushion 12A for the occupant P to sit forward and a seat back 12B that supports the seated occupant P seated on the seat cushion 12A from the rear of the vehicle.

  A windshield glass 14 that defines the front end of the vehicle in the passenger compartment C is disposed in front of the passenger seat 12. An instrument panel 16 is provided below the vehicle with respect to the windshield glass 14. The instrument panel 16 protrudes toward the passenger seat 12, and the seated occupant P seated on the passenger seat 12 puts his / her feet into the space below the instrument panel 16. Therefore, the seated occupant P seated in the passenger seat 12 brings the knee K close to the instrument panel 16 in the seated posture.

  The passenger seat airbag apparatus 10 includes an airbag module 18 disposed in the instrument panel 16. The airbag module 18 includes an airbag 20 that will be described in detail later, an inflator 22 as a gas supply device for supplying gas to the airbag 20, and an airbag that holds (partially accommodates) the airbag 20 and the inflator 22. The case 24 is configured as a main part. The airbag module 18 is held by an attachment portion 16 </ b> A provided on the instrument panel 16 in the airbag case 24.

  In this embodiment, as shown in FIG. 1, the airbag 20 includes a main bag 26 as an upper body protection bag for protecting the upper body U of the seated occupant P, and a knee protection for protecting the knee K. And a sub-bag 28 as a bag. For this reason, in the passenger seat airbag device 10, the airbag module 18 is provided in the vicinity of the rearmost portion of the vehicle in the instrument panel 16 so as to face the vehicle rearward and upward. Specifically, in the airbag device 10 for the passenger seat, the airbag case 24 of the airbag module 18 is held by the mounting portion 16A of the instrument panel 16 in a posture that opens toward the rear of the vehicle and upward of the vehicle. Yes.

  The airbag case 24 holds (partially accommodates) the airbag 20 in a folded state as shown by a two-dot chain line in FIG. The airbag 20 is kept in a folded state by being wrapped in a holding sheet or the like (not shown). The inflator 22 is fixedly held by the airbag case 24 in a state in which a part including the gas ejection port 22 </ b> A is inserted into the airbag 20. In this embodiment, the inflator 22 is a so-called disk-type inflator, and a sufficient gas capacity is ensured for the airbag 20 having the main bag 26 and the subbag 28 as described above.

  The main bag 26 of the airbag 20 is inflated and deployed between the windshield glass 14 and the instrument panel 16 and the upper body U of the seated occupant P so as to restrain the relative movement of the upper body U toward the front of the vehicle. It has become. In this embodiment, a vent hole 25 for adjusting internal pressure is formed in the main bag 26. The sub bag 28 is inflated and deployed between the instrument panel 16 and the knee K, and restrains the relative movement of the knee K forward of the vehicle. The main bag 26 and the sub bag 28 of the airbag 20 are integrally configured as shown in FIGS.

  Specifically, the main bag 26 is formed so as to be inflated and deployed in a bag shape by a base cloth 30 that constitutes an upper portion and an intermediate portion of the airbag 20 in the vehicle vertical direction. In this embodiment, the main bag 26 is a so-called twin chamber structure airbag in which left and right bags adjacent in the vehicle width direction are connected as shown in FIG. The main bag 26 is formed such that the rear ends of the left and right bags (chambers) restrain the left and right shoulders (or the vicinity thereof) of the seated occupant P, respectively.

  The sub bag 28 is formed in a bag shape that opens upward in the vehicle with the base cloth 32, and the opening edge is joined to the vehicle lower opening edge of the main bag 26 by sewing or the like. Thereby, the airbag 20 has comprised the big bag shape as a whole. The base fabric 32 is different from the base fabric 30 in that the surface is subjected to a texture seal process such as a silicon coat, and prevents gas leakage from the main bag 26 via the texture (suppresses the base fabric 30). ). The silicon coat for holding the internal pressure of the sub bag 28 is preferably applied to the inner surface of the sub bag 28 from the viewpoint of preventing gas leakage.

  As described above, the airbag 20 deployed as a large bag as a whole has a tether 34 as a cloth-like material for partitioning (separating) the interior into a chamber of the main bag 26 and a chamber of the subbag 28. The tether 34 has a cloth shape and regulates the expansion of the sub bag 28 in the vehicle front-rear direction as shown in FIGS. 1 and 2. In this embodiment, the tether 34 is joined to the sewing part of the base fabric 30 and the base fabric 32 by sewing etc. as shown in FIG.

  In addition, as shown in FIG. 2, a tether 46 is provided in the sub bag 28 as a regulating member for regulating the expansion (thickness) of the sub bag 28 in the vehicle front-rear direction. In this embodiment, two tethers 46 are provided apart from each other in the vertical direction. In this embodiment, the vertical position of the upper tether 46 is set to substantially match the vertical position of the occupant P's knee center. Each tether 46 is formed with a through-hole 46A (see FIG. 3), and the through-hole 46A communicates in the sub-bag 28 up and down.

  The airbag 20 according to this embodiment includes an inner tube 35 as a flexible gas flow path member that guides the gas of the inflator 22 to the main bag 26 and the subbag 28. The inner tube 35 is opened by a base fabric 36, which is the same fabric as the base fabric 30, independent of the main bag 26 and the sub bag 28, in front of the vehicle and downward of the vehicle, as shown in FIG. It is configured as a bag body that is expanded and deployed in a substantially “U” shape. Specifically, as described above, the inner tube 35 includes an upper portion 38 extending in the opening direction from the airbag case 24 that opens rearward and upward of the vehicle, and from the upper portion 38 to the front of the vehicle and to the lower side of the vehicle. The lower part 40 which is unfolded so as to be folded is configured as a main part.

  A lower portion 40 of the inner tube 35 penetrates the tether 34, and a gas supply port 40A for supplying gas to the sub bag 28 is formed at the tip thereof. On the other hand, a gas supply port 38 A for supplying gas to the main bag 26 is formed in the vicinity of the folded portion of the lower portion 40 in the upper portion 38 of the inner tube 35, that is, on the main bag 26 side with respect to the tether 34. In this embodiment, as shown in FIG. 3, the gas supply port 38 </ b> A is formed as a through hole penetrating the base cloth 36 on both sides in the vehicle width direction of the upper portion 38 of the inner tube 35. Thus, in the passenger seat airbag apparatus 10, gas is supplied into the main bag 26 from the upper portion 38 of the inner tube 35 toward both sides in the vehicle width direction.

  Further, in the passenger airbag device 10, a check valve (one-way valve) 42 is formed around the gas supply port 40 </ b> A in the lower portion 40 of the inner tube 35 as gas discharge suppression means. The check valve 42 has a cloth piece 42A that covers the gas supply port 38A from the inside of the sub bag 28, and allows gas supply to the sub bag 28 from the upper part 38 through the gas supply port 38A. On the other hand, the check valve 42 is configured such that when the internal pressure (dynamic pressure) of the sub bag 28 becomes higher than the internal pressure of the upper portion 38, the cloth piece 42A closes the gas supply port 38A by the internal pressure. In order to facilitate understanding of the configuration of the check valve 42, FIG. 2 shows a closed state of the gas supply port 40A when the check valve 42 is inactive, and FIG. The open state is illustrated.

  Further, as shown in FIG. 1, an airbag door 44 that is broken and opened by the inflation and deployment pressure of the airbag 20 is formed at a portion of the instrument panel 16 to which the airbag module 18 is attached. The airbag door 44 according to this embodiment is opened up and down around the hinge portion when the instrument panel 16 is cleaved at a groove-like tear line formed on the inner surface thereof, and the instrument panel 16 is opened. It comes to form. Through this opening, the airbag 20 is allowed to be expanded and deployed outside the instrument panel 16, that is, into the passenger compartment C.

  In the passenger-side airbag device 10 described above, for example, when a frontal collision of the vehicle V is detected or predicted to be unavoidable based on an output of a collision sensor (not shown), an airbag as a control device (not shown) is used. The ECU operates the inflator 22.

(Folding structure of sub bag)
The sub bag 28 of the airbag device 10 for the passenger seat described above includes the upper bag 48 that is deployed on the upper side in the vertical direction, and the lower bag 50 that is continuous with the upper bag 48 and deployed on the lower side in the vertical direction. . As shown in FIG. 4, the upper bag 48 is inflated and deployed mainly on the upper side in the vertical direction with respect to the knee K of the occupant P prior to the lower bag 50.

  As shown in FIG. 5, the lower bag 50 is configured to take a posture of being folded back to the front side (the instrument panel 16 side) with respect to the upper bag 48 when the sub bag 28 is deployed. Specifically, the lower bag 50 is folded back to the front side of the upper bag 48 so that the lower bag 50 is rolled inward on the front side of the upper bag 48, and the tear seam 52 is maintained so that the folded state is maintained. The upper bag 48 is sewn.

  The tear seam 52 is broken as the lower bag 50 is inflated and deployed (by the deployment pressure of the lower bag 50). Accordingly, when the upper bag 48 is inflated and deployed and gas is supplied to the lower bag 50, the tear bag 52 is broken along with the expansion and deployment of the lower bag 50. It is configured to be expanded and deployed forward.

  Next, the operation of this embodiment will be described.

  In the passenger airbag device 10 configured as described above, when a frontal collision of the automobile V is detected or predicted based on a signal from the collision sensor, the airbag ECU activates (ignites) the inflator 22. Then, the airbag 20 that has received the gas supply from the inflator 22 is inflated in the instrument panel 16, and inflated and deployed in the vehicle compartment C through an opening formed by deploying the airbag door 44 with the deployment pressure. .

  At this time, the inner tube 35 supplied with the gas from the inflator 22 is first expanded and deployed. The gas from the inflator 22 is supplied to the main bag 26 through a gas supply port 38A formed in the upper portion 38 of the inner tube 35, and the sub bag 28 through the gas supply port 40A formed in the lower portion 40 of the inner tube 35. To be supplied. Then, the sub bag 28 is inflated and deployed between the instrument panel 16 and the knees K of the occupant P, and the main bag 26 having a relatively large capacity is the upper body of the occupant P after the deployment of the sub bag 28 is completed. Deployment is completed in front of the vehicle with respect to U.

  The sub bag 28 restrains the knee K of the seated occupant P seated on the passenger seat 12 and reduces the load acting on the knee K from the instrument panel 16 side. That is, the knee K of the seated occupant P is protected. In particular, in the passenger airbag device 10, the check valve 42 is provided on the gas supply port 40 </ b> A side in the lower portion 40 of the inner tube 35, so that the internal pressure of the sub-bag 28 increases as the knee K is restrained. The check valve 42 closes the gas supply port 40A. For this reason, a decrease in the internal pressure (gas discharge) of the sub-bag 28 accompanying the restraint of the knee K is suppressed, and the knee K of the seated occupant P is better protected.

  On the other hand, the upper body U of the occupant P is restrained by the inflated and deployed main bag 26 and absorbs shock. Accordingly, the passenger P is well protected by the passenger seat airbag device 10. In particular, in the passenger seat airbag apparatus 10, gas is supplied toward both sides in the vehicle width direction in the main bag 26 through the left and right gas supply ports 38A. For this reason, compared with the configuration in which gas is supplied to the rear of the vehicle, the deployment force (deployment speed) of the main bag 26 toward the rear of the vehicle is suppressed, and the load is reduced when restraining the upper body U of the seated occupant P. Is done.

  Here, in the airbag device 10 for the passenger seat, the lower portion of the sub bag 28 is folded back to the instrument panel side with respect to the upper bag 48 and is rolled inward. For this reason, when the tear seam 52 is broken as shown in FIG. 6 after the upper bag 48 is deployed above the knee, the lower bag 50 is placed in the compartment C of the instrument panel 16 as shown in FIG. It is expanded and deployed while eliminating the roll fold so as to roll on the surface on the side (leads to the deployment completion state shown in FIG. 8). In other words, the lower bag 50 of the sub-bag 28 is deployed downward along the surface of the instrument panel 16. As a result, the lower bag 50, which is the tip side of the sub-bag 28, is unfolded while entering the narrow gap between the instrument panel 16 and the knee K of the occupant P.

  As described above, in the passenger seat airbag device 10 according to the present embodiment, since the airbag case 24 is housed integrally with the main bag 26, the sub-deployment is performed downward from above the vehicle with respect to the knee K of the seated occupant P. The bag 28 can be satisfactorily deployed between the instrument panel 16 and the knee K of the occupant P. In particular, in the configuration in which the upper portion 38 of the inner tube 35 is deployed upward and rearward from the airbag case 24, the subbag 28 is deployed from the upper side of the vehicle to the lower side. With the configuration in which the sub bag 28 is deployed along the instrument panel 16 while canceling roll folding, the sub bag 28 can be satisfactorily deployed between the instrument panel 16 and the knee K of the passenger P.

  Further, the lower bag 50 in the roll folded state in the sub bag 28 is maintained in a folded state toward the front side with respect to the upper bag 48 by the tear seam 52 that can sew the lower bag 50 to the upper bag 48 with a stable strength setting. The reliability of holding the lower bag 50 in the folded state with respect to the upper bag 48 in the initial stage of deployment and releasing the held state in the middle stage of deployment is high. That is, the reliability of deploying the sub bag 28 between the instrument panel 16 and the knee K of the occupant P as described above is high.

  In the above-described embodiment, the example in which the holding structure by the folding of the lower bag 50, the roll folding, and the tear seam 52 is applied to the sub bag 28 formed integrally with the main bag 26 has been described. For example, a structure in which a lower bag 50 is folded, rolled, and a holding structure with a tear seam 52 is applied to a knee airbag that is individually inflated and deployed. Therefore, the airbag in the present invention is not limited to the airbag for the passenger seat, and can be applied to an airbag device for the front seat for protecting the knee K of the occupant P against contact with the instrument panel. .

  In the above-described embodiment, an example in which two tethers 46 are provided in the lower bag 50 of the sub-bag 28 is shown. However, the present invention is not limited to this, and for example, one or three or more tethers 46 are provided. Alternatively, the expansion (thickness) of the sub bag 28 may be regulated by a strap or the like instead of the tether.

  Furthermore, in the above-described embodiment, an example in which the sewing structure by the tear seam 52 is provided as the folding holding means is shown. However, the present invention is not limited to this. 50 holding structures can be employed as the folding holding means.

  Furthermore, in the above-described embodiment, an example in which the sub bag 28 is formed integrally with the main bag 26 is provided with the inner tube 35. However, the present invention is not limited to this, and for example, the inner tube A configuration without 35 is also possible. Further, in the configuration including the inner tube 35, for example, the gas supply port 38A is closed with a tear seam or the like that is broken by a gas pressure of a predetermined value or more, and after the inner pressure of the inner tube 35 is increased (the deployment of the sub bag 28). There may be provided a deployment delay structure in which the deployment of the main bag 26 is started in the process or after completion of deployment.

  Further, in the above-described embodiment, the example in which the check valve 42 is provided as the internal pressure holding (gas discharge suppression) means of the sub bag 28 has been shown, but the present invention is not limited thereto, for example, as the internal pressure holding means, You may employ | adopt the string etc. which close the lower part 40 of the inner tube 35 with expansion | swelling of the main bag 26 or the subbag 28, and expansion | deployment.

  Furthermore, in the above-described embodiment, an example in which the main bag 26 is a so-called twin-chamber structure airbag in which the left and right bags are connected is shown, but the present invention is not limited to this, and for example, the main bag 26 is a single bag. It is good also as a structure which is what is called a single chamber structure airbag which has one chamber.

10 Airbag device for passenger seat 16 Instrument panel 22 Inflator (gas supply means)
26 Main Bag (Body Protection Bag)
28 Subbag (Knee Protection Bag)
48 Upper bag 50 Lower bag 52 Tear seam (folding holding means)

Claims (2)

An upper bag that is folded above the occupant's knee in the instrument panel in the vertical direction of the vehicle and is deployed downward in the vertical direction of the vehicle on the passenger compartment side with respect to the instrument panel; A lower bag that is folded back so as to be positioned on the instrument panel side with respect to the bag and rolled inward so as to be inward in the folded state, and the lower bag in the roll folded state is sewn to the upper bag by a tear seam. configured Te, knee protection bags having a folded holding means the maintenance condition is cleared by the deployment pressure by the gas supply through the upper bag of the lower bag with to maintain the folded state of the lower bag against the upper bag When,
A gas supply device for supplying gas into the upper bag in the knee protection bag;
An airbag device comprising: An upper body protection bag that restrains the upper body of a vehicle occupant from the front side in the vehicle front-rear direction by being inflated and deployed on the vehicle compartment side with respect to the instrument panel upon receiving gas supply from the gas supply device, The airbag device according to claim 1, wherein the airbag device is folded together with the protective bag .

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