JP2012006443A - Airbag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an airbag device that facilitates setting of a relation between the timing for gas exhaust and the internal pressure of the airbag at that time, that can efficiently use an inflation gas from a gas generator, and that can obtain sufficient binding force even when using a low-output gas generator.SOLUTION: A hollow protruding part 4 bent to the airbag body 2a side is held in a bent state by a tether 6. A brittle part 6b is formed in a part of the tether 6. When the internal pressure inside the airbag body 2a is increased to a prescribed internal pressure or higher, the brittle part 6b breaks, and the protruding part 4 in the bent state is deformed into a shape protruding from the air- bag body 2a. Consequently, exhaust can be started with a proper timing for the inflation gas inside the airbag body 2a.

Description

  The present invention relates to an airbag apparatus including an airbag that can be inflated and deployed by inflation gas supplied from a gas generator such as an inflator at the time of a vehicle collision or the like. In particular, in the initial stage where the airbag is inflated and deployed, the air provided with an exhaust unit that can quickly inflate and deploy while suppressing exhaust from the airbag and can start exhausting at a desired timing reliably. The present invention relates to a bag device.

  2. Description of the Related Art Conventionally, an air bag device is installed in a vehicle such as an automobile in order to protect an occupant from an impact when the vehicle collides. As an air bag device, in addition to protecting the driver and passenger in the passenger seat, protection for the rear seat occupant and protection of pedestrians, protection of the occupant from impact at the time of side collision of the vehicle and rollover of the vehicle, etc. Various types have been put to practical use. Moreover, the shape of an airbag, etc. differ according to the installation place and use.

  Many airbag devices inflate and deploy bag-like airbags with high-pressure inflation gas generated from a gas generator such as an inflator at the time of a vehicle collision, etc., and absorb and mitigate impacts such as collisions with the airbag. It is configured. Therefore, a configuration for protecting an occupant from an impact or the like is employed.

  The air bag device inflates and deploys the air bag instantaneously with the high-pressure inflation gas ejected from the gas generator, and then releases the gas inside the air bag appropriately at the stage of restraining the occupant. It is comprised so that a passenger | crew can be restrained effectively by adjusting the pressure of.

  As a configuration for appropriately releasing the gas inside the airbag, a configuration in which a vent hole for gas discharge is formed in the airbag body is employed. Conventionally, various configurations have been proposed as the configuration of the exhaust portion via the vent hole. For example, an airbag device (see Patent Document 1) that allows a hole forming member connected to a vent hole to be integrated with an airbag body without impairing the strength required in the vent hole, An air bag device that allows gas to be discharged from the vent hole in the middle, and that can inflate and deploy the air bag to the final shape when the occupant does not contact the air bag in the middle of inflating and deploying (Patent Document) 2), and an airbag system (see Patent Document 3) that can cut a thread sewing an exhaust hole by an internal pressure in an airbag.

  The airbag apparatus described in Patent Document 1 is shown as Conventional Example 1 of the present invention, and FIG. 8 shows a process of inflating and deploying the airbag in a longitudinal sectional view. A pair of left and right vent holes 31 are formed at both ends of the airbag body 30, and a cylindrical hole forming member 32 is attached along the periphery of the vent hole 31. The hole forming member 32 is housed in a folded state in the airbag body 30 during normal times.

  In the first half when the airbag body 30 starts to expand, as shown in FIG. 8A, the hole forming member 32 folded back into the airbag body 30 is strongly pressed against the inner surface of the airbag body 30. It is in. In the second half when the airbag body 30 starts to inflate, as shown in FIG. 8 (b), the hole forming member 32 is bent back and forth at the vent hole 31 and protrudes to the outside of the airbag body 30. Become.

As a result, the pair of left and right vent holes 31 are opened, and the gas inside the air bag body 30 is discharged while controlling the internal pressure in the air bag body 30 to a constant pressure via the vent hole 31 when the passenger is restrained. You can do that.

  The airbag apparatus described in Patent Document 2 is a conventional example 2 of the present invention, and FIG. 9 is a longitudinal sectional view showing the process of inflating and deploying the airbag. FIG. 9A is a cross-sectional view showing a state in which the airbag 40 is inflating and deploying, and FIG. 9B is a cross-sectional view showing the final state of inflating and deploying. is there.

  As shown in FIG. 9A, a pair of vent holes 41 are formed on the left and right sides of the airbag 40, and a reinforcing cloth 41 a is sewn so as to surround the vent hole 41. In order to adjust the exhaust amount of the gas discharged from the vent hole 41, an exhaust adjusting means 42 is provided.

  The exhaust adjustment means 42 includes a tube-like protrusion 43a connected to the peripheral portion of the vent hole 41 and a regulating member 43b made of a string-like object. One end side of the projecting portion 43a is sewn around the vent hole 41, and the other end side extends to the outside of the airbag 40.

  One end of a regulating member 43b is sewn on the inner surface on the front end side of the protrusion 43a, and the other end of the regulating member 43b is sewn on the inner surface of the airbag 40. The length L (see FIG. 9B) from the sewn portion with the inner surface of the airbag 40 at the other end of the regulating member 43b to the sewn portion with the vent hole 41 in the protruding portion 43a is as follows. Is set to such a length that the projecting portion 43a and the regulating member 43b are almost tensioned when in the final inflated and deployed state.

  When the airbag 40 reaches the middle of the inflating and deploying process, the protruding portion 43a is also deployed, and gas can be discharged from the vent hole 41. When the occupant comes into contact with the airbag 40 during the process of inflating and deploying the airbag 40, a part of the inflation gas in the airbag 40 is discharged to the outside through the protrusion 43a. As a result, the inflation pressure in the airbag 40 decreases, so that the occupant can be restrained while reducing the repulsive force acting on the occupant.

  Further, when the occupant does not come in contact during the inflation and deployment of the airbag 40, the airbag 40 can be inflated and deployed to the final inflated and deployed state. Then, as the airbag 40 is inflated and deployed to the final shape, the regulating member 43b is also expanded, and when the regulating member 43b is in a tensioned state, the protruding portion 43a that protrudes outward from the vent hole 41. Is pulled into the airbag 40 through the vent hole 41 by the restricting member 43b in a tension state.

  The protruding portion 43a drawn into the airbag 40 is crushed by receiving the internal pressure of the airbag 40, and restricts the inflation gas in the airbag 40 from being discharged from the vent hole 41 to the outside. Can do. As a result, the inflation gas ejected from the inflator 44 can be used efficiently, and the airbag 40 is inflated and deployed to its final shape by the inflation gas.

  When the occupant comes into contact with the airbag 40 that has been inflated and deployed to the final shape, the portion of the airbag that is sewn to the regulating member 43b is recessed by the occupant's contact, so that the tensioned state of the regulating member 43b is relaxed. As a result, the projecting portion 43a is also loosened, and exhaust from the vent hole 41 becomes possible. As a result, the repulsive force acting on the occupant in contact with the airbag 40 can be mitigated, and the occupant can be reliably restrained.

In the airbag system described in Patent Document 3, an ear portion having an exhaust hole is formed on the outer peripheral portion of the airbag, and after the ear portion is pushed into the airbag, an opening that accommodates the ear portion is sewn. It has a closed configuration. And if the internal pressure in an airbag increases, the thread | yarn which has sewn opening will be fractured | ruptured, an ear | edge part protrudes outside the airbag, and it has the structure which exhausts gas from the exhaust hole formed in the ear | edge part.

Japanese Patent Laid-Open No. 08-268213 JP 2008-207579 A Japanese Patent Laid-Open No. 06-286568

  In the invention described in Patent Document 1, the tube-shaped hole forming member 32 is housed inside the airbag body 30 in the first half when the airbag body 30 starts to expand. In the latter half of the period when the airbag body 30 is inflated and deployed, the inner surface of the airbag body 30 causes the hole forming member 32 to be folded back at the vent hole 31 so that it protrudes outside the airbag body 30. Deform.

  However, the tip of the hole forming member 32 when it is housed inside the airbag body 30 is configured to be freely movable and not restricted at all. For this reason, the timing at which the hole forming member 32 protrudes to the outside of the airbag body 30 depends on the positional relationship between the tip of the hole forming member 32 and the airbag body 30, the internal pressure of the airbag body 30, and the like. There is a risk that it will change each time.

In addition, even if one of the hole forming members 32 arranged in a pair protrudes to the outside and becomes open to the outside air, the other hole forming member 32 May be stored in the airbag body 30.
Thus, in the invention described in Patent Document 1, there is a possibility that exhaust from the airbag body 30 may not be performed as designed.

  Further, when each hole forming member 32 is housed inside the airbag body 30, the end of each hole forming member 32 is configured as a free end, so the length of each hole forming member 32 is Unless configured sufficiently long, the inflation gas leaks to the outside through the hole forming members 32 from the initial stage when the airbag body 30 starts inflating and deploying. If it becomes such a situation, the usage-amount of expansion gas will increase.

  However, if the length of each hole forming member 32 is configured to be long, even if the internal pressure of the airbag body 30 increases, each hole forming member 32 cannot be folded back and forth at the vent hole 31, and the air The bag body 30 cannot protrude outside.

  Thus, when the internal pressure of the air bag body 30 becomes the internal pressure, the shape of the hole forming member 32 projecting from the outside of the air bag body 30 is in a sense that it is left in a certain way. Therefore, it is difficult to specify clearly.

  In the invention described in Patent Document 2, when the occupant does not come in contact with the airbag 40 during inflation and deployment, the airbag 40 can be inflated and deployed to the final inflated and deployed state. Therefore, although the regulating member 43b is provided, the projecting portion 43a projects outward from the airbag 40 during the inflation and deployment of the airbag 40. Therefore, the timing at which the gas is discharged from the protruding portion 43a cannot be regulated by the regulating member 43b.

In the invention described in Patent Document 3, the exhaust hole formed in the ear part and the opening accommodating the ear part are:
It becomes almost the same place. For this reason, the thread that is sewing the opening must be kept closed without opening the opening until the internal pressure of the airbag increases to a predetermined internal pressure. The strength for that is required for the thread sewing the opening.

  In addition, it is necessary to open the opening when the internal pressure in the air bag rises to a certain pressure. For this purpose, an appropriate weakness that breaks quickly against the thread that is sewing the opening. In this way, severe conditions are imposed on the thread sewing the opening.

In addition, when sewing the opening, a high-level sewing technique is required, and a special thread is used as the thread to be used. Moreover, in order to store and sew the ear portion having the exhaust hole in the airbag, a corresponding work man-hour is required.
Thus, in the conventional airbag apparatus, the relationship between the timing for starting the exhaust of gas from the airbag and the internal pressure of the airbag at that time cannot be easily set.

  In the present invention, the above-described conventional problems are solved, and the relationship between the gas exhaust timing and the internal pressure of the airbag at that time can be easily set with a simple configuration. An object of the present invention is to provide an airbag device that can efficiently use inflation gas and can obtain a sufficient restraining force even when a gas generator having a low output is used.

The object of the present invention can be achieved by the inventions described in claims 1 to 5.
That is, in the present invention, in an airbag device including an airbag that can be inflated and deployed by an inflation gas supplied from a gas generator,
The airbag communicates with and surrounds the vent hole formed in the outer shell of the airbag body, surrounding the vent hole, and can protrude outward from the outer shell of the airbag body. A hollow projecting portion made of a flexible member, and holding means for holding the projecting portion folded toward the airbag body side in a folded state.
When the internal pressure of the airbag main body reaches a predetermined internal pressure set in advance, the holding means releases the holding state of the protruding portion in a bent state and protrudes outward from the outer shell of the airbag main body. The most important feature is that the protruding portion functions as an exhaust portion of the airbag body.

  Further, in the present invention, the holding means has a tether that connects the distal end side of the projecting portion in a bent state and the airbag body, and applies a force acting on the tether when the internal pressure of the airbag body increases. The main feature is that the weakened portion is formed in a part of the tether.

  Furthermore, in the present invention, the main feature is that the projecting portion is folded and folded to the inner surface side of the airbag main body in a normal state.

Furthermore, in the present invention, the main feature of the projecting portion is that the opening area at the distal end portion of the projecting portion is narrower than the opening area at the proximal end portion of the projecting portion.
The main feature of the present invention is that a sub-airbag body communicates with the tip of the protruding portion.

According to the configuration of the airbag device according to the present invention, the gas discharge from the airbag body can be stopped at the folded portion of the projecting portion in the folded state, and the folded state is held by the holding means. Can be kept. Further, at this time, the protruding portion, which is held in a bent state by the holding means, can be pressed against the airbag body by the internal pressure of the airbag body.

  In order that the cylindrical portion of the protruding portion held by the holding means is overlaid on the pechanco and more efficiently crimped on the airbag body side, the airflow is reduced at the portion of the protruding portion overlaid on the pechanco. It is a more desirable configuration to hold the portion that is not in contact with the bag body by the holding means.

  By configuring as in the present invention, it is possible to reliably prevent the gas in the airbag body from being discharged from the protrusion when the protrusion is in a bent state. That is, at the initial stage where the inflation and deployment is started, the inflation and deployment can be performed quickly while suppressing the exhaust of gas from the airbag body. Then, when the internal pressure of the airbag body reaches a predetermined internal pressure, the holding means releases the holding state of the protruding portion in the bent state.

  And even if it does not comprise the length of a protrusion part long, the bending state of a protrusion part can be reliably hold | maintained by a holding means. And the protrusion part can be easily deform | transformed into the state protruded outward from the outer shell of the airbag main body by releasing the restraining force of the holding means held in the bent state. Then, exhaust can be started at an appropriate timing with respect to the inflation gas in the airbag body.

  In this way, the holding means can adjust the timing for releasing the holding state of the protruding portion, so the relationship between the timing for releasing the holding state of the protruding portion in the bent state and the internal pressure of the airbag body at that time Can be set easily. Moreover, even when a gas generator having a low output is used as the gas generator, a sufficient restraining force necessary for the airbag can be obtained. And the cost reduction can be aimed at and size reduction of an airbag apparatus can be implement | achieved.

  In the present invention, the holding means can be configured using a string-like or belt-like tether. And as a structure which open | releases the holding | maintenance state of a protrusion part, the structure which formed the weak part in the tether is employable.

  As the weakened portion formed on the tether, the thread in the direction intersecting the direction of the force acting on the tether when the internal pressure of the airbag main body rises among the structure in which the tether is formed with a perforation or the woven yarn knitting the tether The structure etc. which extracted are employable. The configuration of the weakened portion formed on the tether is not limited to the above-described configuration, and the protruding portion is formed by the weakened portion formed on the tether when the internal pressure of the airbag main body reaches a predetermined internal pressure set in advance. Various configurations may be employed as long as the configuration in which the holding state is released is used.

  For example, when a configuration using an engagement portion that engages and disengages the end portion of the tether and the airbag main body as the fragile portion is adopted, the internal pressure of the airbag main body reaches a predetermined internal pressure set in advance. The engagement state at the engagement portion can be released.

  As the engaging portion, a configuration in which the end portion of the tether and the airbag body are sewn using a thread that is broken by a predetermined stress, a configuration using a hook-and-loop fastener, or the like can be employed. When a thread that breaks at a predetermined stress is used as the engaging portion, the thread only needs to be broken at a predetermined stress. As in the invention of Patent Document 3, both conditions of a predetermined strength and a break are satisfied. There is no need to keep it.

  In the present invention, as the bent configuration of the projecting portion that is bent in a normal state, a configuration folded on the outer surface side of the airbag main body or a configuration folded on the inner surface side of the airbag main body can be adopted. Whichever configuration is adopted, the bent state can be held by the holding means. Then, when the internal pressure of the airbag body rises to a predetermined internal pressure, the holding state of the protruding portion by the holding means is released, and the protruding portion is protruded, whereby the timing for exhausting gas from the airbag body is set. Can be set.

  In this invention, it can comprise so that the opening area in a front-end | tip part may become narrow rather than the opening area in a base end part as a structure in a protrusion part. By configuring in this way, it is possible to prevent the inflation gas in the airbag body from being released at a stretch even when the protruding portion is in the protruding state and functions as an exhaust portion.

  Further, since the protruding portion has a tapered shape, the protruding portion bent in the airbag main body is easily pushed out to the outside when the internal pressure of the airbag main body rises to a predetermined internal pressure.

  In this invention, it can also be set as the structure which made the sub-airbag body communicate with the front-end | tip part of a protrusion part. By making the sub-airbag body communicate with the tip of the protruding portion, the sub-airbag body can be used as a gas for inflating without releasing the inflation gas generated by the gas generator to the outside air. it can. For example, in an airbag device having a main expansion chamber and a sub-expansion chamber, such as a side airbag, the gas that has expanded the main expansion chamber is used for the expansion of the sub-expansion chamber without letting it escape to the outside air. . And the passenger | crew is ensured from an impact with the main expansion chamber and the subexpansion chamber.

  As described above, the airbag body is configured as the main inflation chamber and the secondary airbag body is configured as the secondary inflation chamber, thereby providing a time difference between the expansion of the airbag body and the expansion of the secondary airbag body. The airbag device of the present invention can be configured as the bag device.

It is the perspective view and top view which show the bending state and protrusion state of a protrusion part. Example 1 It is sectional drawing which shows the bending state and protrusion state of a protrusion part. Example 1 It is sectional drawing which shows the bending state and protrusion state of a protrusion part. (Example 2) It is sectional drawing which shows the bending state of a protrusion part, and its principal part enlarged view. (Example 3) It is a perspective view which shows the bending state and protrusion state of a protrusion part in the structure which connected the sub-airbag body to the vent hole. Example 4 It is a perspective view which shows the bending state and protrusion state of a protrusion part in the structure which connected the sub airbag body to the protrusion part. (Example 5) It is the perspective view and top view which show the bending state and protrusion state of a protrusion part. (Example 6) It is sectional drawing which shows the expansion | deployment deployment process of an airbag. (Conventional example 1) It is sectional drawing which shows the expansion | deployment deployment process of an airbag. (Conventional example 2)

Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings. As an airbag apparatus according to the present invention, an airbag body having a bag-like shape will be described below as an example. The airbag device according to the present invention is not limited to the configuration in which the airbag body is formed in a single bag shape, but a side airbag having a secondary airbag body, a side curtain airbag, and a rear seat. The present invention can also be suitably applied to airbags, front curtain airbags, outdoor airbags, and the like. For this reason, this invention is not limited to the Example demonstrated below, A various change is possible.

  The structure of the airbag apparatus according to the present invention will be described with reference to FIGS. As shown in FIGS. 1A, 1C, and 2, the airbag 2 is made of a non-breathable flexible material, for example, a nylon base fabric panel with a rubber coating on the inside. The air bag main body 2a is stitched into a bag shape. As the configuration of the airbag main body 2a, a disk-shaped configuration is shown, but this configuration is an example, and other configurations can be adopted as long as the configuration is necessary as an airbag.

1 (a) and 1 (b) are perspective views of an airbag main body 2a that has started to be inflated and deployed when a collision or the like occurs in the vehicle, from the side of the passenger restraint surface 10 on which an occupant contacts the airbag main body 2a. Is shown. Note that the airbag body 2a is held in a folded state during normal times. Moreover, FIG.1 (c), (d) has shown the back surface side on the opposite side to the passenger | crew restraint surface 10 in the airbag main body 2a. FIG. 2 shows a cross-sectional view of the main part of the airbag device.
In FIG. 1, configurations of the inflator 7 and the inflator attaching portion 8 that are disposed on the back surface side of the airbag body 2a are omitted. Further, in FIG. 1B, illustration of the tether 6 constituting the holding means 5 described later is omitted. Further, in FIG. 2, the configuration of the airbag cover or the like is omitted.

  As shown in FIG. 2, an inflator 7 as a gas generator is attached to the central portion on the back side of the airbag body 2a. Further, a vent hole 3 for gas discharge is formed in the outer shell of the airbag main body 2a, and the periphery of the vent hole 3 is surrounded by a hollow protruding portion 4.

  The protrusion 4 is made of a non-breathable flexible material, and is integrally formed with the airbag body 2a so as to protrude from the airbag body 2a. As shown in FIGS. 1 (c) and 2 (a), there is provided holding means 5 for holding the bent state when the hollow cylindrical portion of the protruding portion 4 is crushed and bent. Instead of integrally forming the protruding portion 4 with the airbag body 2a, it may be configured separately from the airbag body 2a and sewn into the vent hole 3 of the airbag body 2a.

  The holding means 5 has a configuration including a string-like or belt-like tether 6, and one end of the tether 6 is sewn to the tip of the protruding portion 4. The other end portion of the tether 6 is attached to the inflator attachment portion 8 of the inflator 7 in the same manner as the opening end of the airbag body 2a. As shown in FIGS. 1C, 1 </ b> D, and 2, the through hole formed in the other end portion of the tether 6 is inserted into a mounting bolt 8 a provided in the inflator mounting portion 8.

A through-hole formed in the opening end of the airbag body 2a is also inserted into the mounting bolt 8a, and the other end of the tether 6 and the opening end of the airbag body 2a are the bottoms constituting the inflator mounting portion 8. It is clamped and fixed between the wall portion 9a and the flange portion 9b.
In addition, although the example which comprised the tether 6 separately from the protrusion part 4 was demonstrated, the tether 6 can also be comprised by extending the protrusion part 4 integrally.

  The tip of the protrusion 4 that sews one end of the tether 6 is the side that does not contact the airbag body at the tip of the protrusion 4 when the tubular portion of the protrusion 4 is crushed and bent. It is a part of. As shown in FIGS. 1C, 1D, and 2B, the airbag body 2a is inflated and deployed at the intermediate portion in the longitudinal direction of the tether 6 until the internal pressure of the airbag body 2a reaches a predetermined internal pressure. When this is done, a fragile portion 6b that will break is formed.

  Even if the length of the protrusion 4 is not long, the tip 4 of the protrusion 4 that sews one end of the tether 6 is bent as described above. The state can be reliably maintained. Then, when the restraining force of the tether 6 that has been held in a folded state by breaking the tether 6 is released, the projecting portion 4 can be easily deformed to project outward from the outer shell of the airbag body 2a. Can do. Then, it is possible to start exhausting the inflation gas in the airbag body 2a at an appropriate timing.

  The fragile portion 6b is configured by forming a perforation in the tether 6, or, among the woven yarns knitting the tether 6, acts on the tether 6 when the internal pressure of the airbag body 2a increases. It can be set as the structure which extracted the thread | yarn of the direction which cross | intersects the direction of the force to perform. Further, it is possible to adopt a configuration in which a cut is formed in a direction intersecting the direction of the force acting on the tether 6 when the internal pressure of the airbag body 2a is increased, and the internal pressure of the airbag body 2a is set to a predetermined value. As long as the fragile portion 6b is broken when the internal pressure is reached, another configuration can be adopted.

  As shown in FIGS. 1 (c) and 2 (a), the length from the end of the tether 6 attached to the inflator attaching portion 8 to the base end 4b of the bent projection 4 is an airbag. When the main body 2a is not inflated and deployed, the main body 2a can be configured to have a length that is substantially a quarter of the circumferential length of the airbag main body 2a.

  By configuring in this way, when the internal pressure of the airbag body 2a rises to a predetermined pressure, the length from the inflator attachment portion 8 to which the tether 6 is attached to the base end portion 4b of the protrusion 4 is increased. , It will be stretched longer than normal. As a result, a tensile force acts on the tether 6, and the fragile portion 6b is broken by the tensile stress.

  That is, at the stage where the internal pressure of the airbag main body 2a has not increased to a predetermined pressure, the bent state of the protruding portion 4 is held by the holding means 5 as shown in FIGS. 1 (c) and 2 (a). In this state, no gas leaks from the vent hole 4. When the internal pressure of the airbag body 2a reaches a predetermined level, as shown in FIG. 1 (d) and FIG. 2 (b), the fragile portion 6b of the tether 6 is broken, and the protruding portion 4 protrudes from the airbag main body 2a, passes through the vent hole 4 and the protruding portion 4, and discharges the inflation gas in the airbag main body 2a to the outside.

  As a configuration of the protruding portion 4, the opening area at the distal end portion 4a can be formed to be narrower than the opening area at the base end portion 4b of the protruding portion 4. By configuring in this way, even when the projecting portion 4 is in a projecting state and functions as an exhaust section that discharges the inflation gas in the airbag body 2a to the outside, the inflation gas in the airbag body 2a is at a stretch. It can be prevented from coming off.

  Further, by forming the projecting portion 4 in a tapered shape, the projecting portion 4 bent in the airbag body 2a is exposed to the outside when the internal pressure of the airbag body 2a rises to a predetermined internal pressure. It becomes easy to be pushed out.

  The configuration of Embodiment 2 according to the present invention will be described with reference to FIG. In the second embodiment, as shown in FIG. 3, the projecting portion 4 is folded back into the airbag body 2a, and the folded projecting portion 4 is folded. The bent state of the protrusion 4 is held by the tether 6 constituting the holding means 5. Other configurations are the same as those in the first embodiment.

  Therefore, about the structure similar to the structure in Example 1, the description about the member is abbreviate | omitted by using the member code | symbol used in Example 1. FIG. Further, as described in the first embodiment, the tether 6 can be configured as a part of the protruding portion 4.

  3 (a) and 3 (b) are cross-sectional views of the main part of the airbag device. As shown in FIG. 3 (a), the protruding portion 4 that is folded back and folded into the airbag body 2a has its distal end portion 4a sewn at one end of the tether 6 and the sewn portion 6c. 6 and the inner wall surface of the airbag main body 2a are arranged so that the tip end portion 4a of the protruding portion 4 is sandwiched. The other end of the tether 6 is attached to the inflator attachment portion 8.

  As shown in FIG. 3 (a), when the internal pressure of the airbag body 2a is increased to a predetermined internal pressure or higher, the tether 6 is formed in a part of the tether 6 by a tensile stress acting in the longitudinal direction of the tether 6. 6 breaks. Then, as shown in FIG. 3B, the protruding portion 4 folded back into the airbag main body 2a protrudes outward from the airbag main body 2a in a state where the front and back sides are reversed in the vent hole 3.

  Until the internal pressure of the airbag main body 2a is increased to a predetermined internal pressure or higher, the protrusion 4 that is folded back and folded into the airbag main body 2a is sandwiched between the tether 6 and the inner wall surface of the airbag main body 2a. As a result, the bent state of the protrusion 4 can be reliably maintained.

  For this reason, even if the length of the protrusion 4 is not long, the tether 6 can reliably hold the bent state of the protrusion 4. When the tether 6 that has maintained the bent state of the protruding portion 4 is broken, the protruding portion 4 can easily protrude from the vent hole 3 to the outside of the airbag body 2a. As a result, it is possible to start exhausting the inflation gas in the airbag body 2a at an appropriate timing.

  The configuration of Embodiment 3 according to the present invention will be described with reference to FIG. In Example 3, as shown in FIG. 4, as the structure of the holding means 5 that holds the bent state of the protruding portion 4, the other end portion of the tether 6 having one end portion sewn to the distal end portion 4 a of the protruding portion 4 is It is configured to be detachably engaged with the outer shell portion of the airbag main body 2a via the engaging portion 12. Other configurations are the same as those in the first embodiment.

Therefore, about the structure similar to the structure in Example 1, the description about the member is abbreviate | omitted by using the member code | symbol used in Example 1. FIG. Further, as described in the first embodiment, the tether 6 can be configured as a part of the protruding portion 4.
FIG. 4A shows a cross-sectional view of the main part of the airbag device. FIG. 4B shows an enlarged view of a main part around the engaging portion 12.

  As shown in FIG. 4 (a), the protruding part 4 bent outward of the airbag body 2a has its tip part 4a sewn at one end of the tether 6 and a sewn part 6c. The front end 4a of the protrusion 4 is sandwiched between the outer shell of the airbag body 2a. The engaging portion 12 that engages the other end portion of the tether 6 with the airbag body 2a has a configuration using a hook-and-loop fastener, and a male surface 13a of the hook-and-loop fastener is provided at the other end of the tether 6. Yes. A female surface 13b of a hook-and-loop fastener is provided on the outer shell of the airbag body 2a.

When the internal pressure of the airbag body 2a is increased to a predetermined internal pressure or higher, the projecting portion 4 is inflated, and the other end side of the tether 6 rotates counterclockwise in FIG. 4B. The male surface 13a provided at the other end of the tether 6 is also rotated by the rotation at the other end side of the tether 6 to the female surface 13b.
On the other hand, it rotates in the counterclockwise direction in FIG. As a result, the male surface 13a is sequentially disengaged from the protruding portion 4 side with respect to the female surface 13b, and finally the engagement state between the male surface 13a and the female surface 13b is released. become.

  When the engagement at the engagement portion 12 is released, the protrusion 4 is deformed into a state of protruding outward from the airbag body 2a. Then, the protruding portion 4 in the protruding state functions as an exhaust portion that discharges the inflation gas in the airbag body 2a to the outside.

  As a configuration of the engaging portion 12, a configuration in which the other end of the tether 6 and the outer shell of the airbag body 2a are sewn can be used instead of the configuration using the hook-and-loop fastener. At this time, as a sewing thread for sewing between the other end of the tether 6 and the outer shell of the airbag main body 2a, it acts on the tether 6 when the internal pressure of the airbag main body 2a is increased to a predetermined internal pressure or higher. A yarn having a strength that can be broken by a tensile force can be used.

  The configuration of Embodiment 4 according to the present invention will be described with reference to FIG. In the fourth embodiment, as shown in FIG. 5, the airbag device 1 includes a secondary airbag body 2b in addition to the airbag body 2a. The airbag main body 2a and the secondary airbag body 2b are partitioned by a boundary surface 18, and the boundary surface 18 is formed with a vent hole 3 that communicates the airbag main body 2a and the secondary airbag body 2b. .

  A protrusion 4 is sewn to the vent hole 3, and the periphery of the vent hole 3 is surrounded by the protrusion 4. One end of the tether 6 is sewn to the tip 4a of the protrusion 4 that is folded back into the airbag main body 2a, and the other end of the tether 6 is fixed to the inflator mounting portion 8. Further, a fragile portion 6b is formed in the middle portion of the tether 6 in the longitudinal direction. The configuration of the inflator mounting portion 8 is the same as that of the first embodiment. As described in the first embodiment, the tether 6 can be configured as a part of the protruding portion 4.

  The tip 4a of the protrusion 4 folded back into the airbag body 2a is in a state of being folded by the tether 6, and until the internal pressure of the airbag body 2a is increased to a predetermined internal pressure, the airbag body 2a The inflation gas supplied from the inflator 7 is pressed against the inner wall surface of the airbag body 2a. Then, the inflation gas in the airbag main body 2a is prevented from flowing into the auxiliary airbag body 2b through the protruding portion 4.

  As shown in FIG. 5 (b), when the internal pressure of the airbag body 2a is increased to a predetermined internal pressure or higher, the tether 6 is formed in a part of the tether 6 by a tensile stress acting in the longitudinal direction of the tether 6. 6 breaks. Then, as shown in FIG. 5B, the protruding portion 4 that has been folded back into the airbag body 2 a protrudes into the auxiliary airbag body 2 b with the front and back reversed in the vent hole 3.

  The projecting portion 4 projecting into the secondary airbag body 2b functions as an exhaust section for allowing the inflation gas in the airbag body 2a to flow into the secondary airbag body 2b. In addition, the inflation gas generated in the inflator 7 can be used as a gas for inflating the auxiliary airbag body 2b without releasing it into the outside air. For example, in an airbag device including a main inflation chamber and a sub-inflation chamber, such as a side airbag, the airbag body 2a is configured as a main expansion chamber, and the sub-airbag body 2b is configured as a sub-inflation chamber. I can leave.

The configuration of Embodiment 5 according to the present invention will be described with reference to FIG. In the fifth embodiment, as shown in FIG. 6, the airbag device 1 includes a secondary airbag body 2b in addition to the airbag body 2a. The airbag main body 2a and the auxiliary airbag body 2b are configured to communicate with each other via the protruding portion 4. Other configurations are the same as those in the first embodiment.

The protruding part 4 is bent to the outer shell side of the airbag body 2a, and the tether 6 is attached via the auxiliary airbag body 2b connected to the protruding part 4, and the other end part of the tether 6 is implemented. As in Example 1, it is fixed to the inflator mounting portion 8.
When the auxiliary airbag body 2b connected to the protruding portion 4 is further bent to the airbag body 2a side, one end portion of the tether 6 may be attached to the distal end portion of the protruding portion 4. it can. With this configuration, the auxiliary airbag body 2b bent toward the airbag body 2a can be pressed against the airbag body 2a by the protrusion 4 and the tether 6.

  As shown in FIG. 6 (a), the protruding portion 4 bent to the outside of the airbag body 2a has a configuration in which the auxiliary airbag body 2b is communicated with the distal end portion 4a. The outer shell is sewn at one end of the tether 6 and the sewn portion 6c. The bent state of the protruding portion 4 is maintained by the tether 6.

  When the internal pressure of the airbag body 2a is increased to a predetermined internal pressure or higher, the fragile portion 6b formed in the tether 6 is broken. Then, the inflation gas in the airbag main body 2a flows into the auxiliary airbag body 2b through the protruding portion 4. Then, the internal pressure of the airbag main body 2a can be reduced, and the auxiliary airbag body 2b can be inflated.

  By configuring in this manner, as in the fourth embodiment, in the airbag device including the main expansion chamber and the sub-expansion chamber, the airbag body 2a is configured as the main expansion chamber, and the sub-airbag body 2b Can be configured as a secondary expansion chamber.

  The configuration of Embodiment 6 according to the present invention will be described with reference to FIG. In Example 6, as shown in FIG. 7, the airbag main body 2a includes a first vent hole 3 having a large-diameter opening and a pair of second vent holes 15 having a small-diameter opening. . The first vent hole 3 is provided with a hollow first projecting portion 4 surrounding and surrounding the first vent hole 3, and each second vent hole 15 is provided with each second vent hole 15. A hollow second protrusion 16 is provided so as to surround and communicate with each other.

  Both the first projecting portion 4 and the second projecting portion 16 are made of a flexible member, and are configured to project outward from the outer shell of the airbag body 2a. The pair of second protrusions 16 are arranged on the edge side opposite to the edge side of the airbag body 2a where the first protrusions 4 are provided. Then, as shown in FIG. 7C, the pair of second protrusions 16 are arranged symmetrically with respect to a center line passing through the first protrusion 4 and the center of the airbag body 2a.

  In addition, a connecting member 17 connects the tip of the first protrusion 4 in a bent state and the tip of the second protrusion 16 in a protruding state. When the internal pressure of the airbag body reaches a predetermined internal pressure, the connecting member 17 has a second projecting portion that is in a projecting state in response to the first projecting portion 4 that has been bent being deformed into a projecting state. It plays a role of deforming 16 into a folded state.

In the sixth embodiment, the vent hole 3 described in the first to fifth embodiments corresponds to the first vent hole, and the protruding portion 4 corresponds to the first protruding portion. In FIG. 7, the tether 6 is provided in the same manner as in the first embodiment in order to maintain the bent state of the first protrusion 4. Therefore, the holding means 5 in the first to fifth embodiments corresponds to a configuration including the connecting member 17 and the tether 6 in the sixth embodiment. As a mounting configuration of the mounting portion 6a of the tether 6 to the airbag main body 2a, a configuration of mounting to the inflator mounting portion 8 can be adopted as in the first embodiment.
When the airbag main body 2a starts to be inflated and deployed by an inflation gas from an inflator (not shown) at a normal time, a part of the inflation gas is released from the second projecting portion 16 to the outside.

  By forming the second vent hole 15, a part of the inflation gas in the airbag body 2a can be discharged from the second vent hole 15 to the outside during the inflation and deployment of the airbag body 2a. And even if a passenger | crew etc. contact | abut to the airbag main body 2a in the initial stage of expansion | deployment deployment, the repulsive force which acts on a passenger | crew etc. can be relieved.

  In addition, a part of the inflation gas continues to be discharged to the outside from the second protrusion 16, but the opening area of the second vent hole 15 connecting the second protrusion 16 is formed as an opening area with a small diameter. Therefore, the discharge flow rate of the expansion gas discharged to the outside through the second protrusion 16 can be kept small.

  By configuring in this way, when an occupant or the like comes into contact with the airbag body 2a in the initial stage of inflation and deployment and the internal pressure of the airbag body 2a rises to a predetermined internal pressure, the occupant or the like When the internal pressure of the airbag main body 2a rises to a predetermined internal pressure without coming into contact with 2a, the first projecting portion 4 that is in the bent state can be in the projecting state. When the first protrusion 4 is in the protruding state, the expansion gas can be discharged to the outside at a desired ratio. Further, when the first projecting portion 4 is in the projecting state, the second projecting portion 16 that is in the projecting state is deformed into a bent state by the connecting member 17.

  In addition, it is possible to configure a state in which no gas is discharged from the first projecting portion 4 and the second projecting portion 16 when the first projecting portion 4 in the bent state is deformed into the projecting state. By configuring such a state, it is possible to realize the control of exhaust → stop → exhaust as control of gas exhausted from the airbag body 2a.

  In order to adjust the timing when the first projecting portion 4 in the bent state is brought into the projecting state, the internal pressure of the airbag body 2a is preset in addition to the configuration in which the connecting member 17 is provided as the configuration of the holding means The holding means 5 may be further provided with a configuration in which a fragile portion 6b that opens the holding state of the first projecting portion 4 in a bent state when the predetermined internal pressure is reached is formed between the mounting portion 6a. it can.

  As an explanation of the sixth embodiment, the configuration in which the fragile portion 6b is formed in the tether 6 between the first projecting portion 4 and the attachment portion 6a has been described, but instead of the fragile portion 6b formed in the tether 6, the third embodiment is described. It is also possible to adopt a configuration using the engaging portion 12 as described in the above.

  As described above, by further providing a configuration for releasing the holding state of the first protrusion 4, the gas in the airbag body 2 a is discharged from the first protrusion 4 when the first protrusion 4 is in a bent state. Can be surely prevented. And when the internal pressure of the airbag main body 2a reaches a predetermined internal pressure, the first projecting portion 4 that has been bent can be reliably deformed to the projecting state.

  Further, in the case where the force for bending the pair of second protruding portions 16 in the protruding state can be obtained by the rising force of the first protruding portion 4 when deformed from the bent state to the protruding state, 1 The tether 6 that connects the protruding portion 4 and the mounting portion 6a may not be provided.

  The technical idea of the present invention can be applied to other configurations of airbags.

1 Airbag device,
2 ... Airbag
2a ... airbag body,
2b ... sub airbag body,
3 ... Vent hole (first vent hole),
4 ... protrusion part (1st protrusion part),
5 ... Holding means,
6 ... tether,
6b fragile part,
8: Inflator mounting part,
12 ... engaging part,
15 ... Second vent hole,
16 ... 2nd protrusion part,
17 ... connecting member,
30 ... Airbag body,
32 ... Hole forming member,
40 ... Airbag,
42 ... exhaust adjustment means,
43a ... protrusion,
43b ... restricting member.

Claims (5)

In an airbag device including an airbag that can be inflated and deployed by an inflation gas supplied from a gas generator,
The airbag is a vent hole for gas discharge formed in the outer shell of the airbag body,
Surrounding and communicating with the periphery of the vent hole, it is possible to project outward from the outer shell of the airbag body, and a hollow projecting portion made of a flexible member;
Holding means for holding the protruding portion bent on the airbag body side in a bent state;
With
When the internal pressure of the airbag main body reaches a predetermined internal pressure, the holding means releases the holding state of the protruding portion in a bent state and protrudes outward from the outer shell of the airbag main body. An airbag device characterized in that a part functions as an exhaust part of the airbag body.   The holding means has a tether that connects the distal end side of the protruding portion in a bent state and the airbag main body, and a weak portion against a force acting on the tether when the internal pressure of the airbag main body increases. The airbag device according to claim 1, wherein the airbag device is formed on a part of the tether.   The airbag device according to claim 1 or 2, wherein the protrusion is in a state of being folded back and bent to an inner surface side of the airbag body in a normal state.   The said protrusion part is formed so that the opening area in the front-end | tip part of the said protrusion part is formed narrower than the opening area in the base end part of the said protrusion part. Airbag device.   The airbag device according to any one of claims 1 to 4, wherein a sub-airbag body communicates with a tip portion of the protruding portion.

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