JP2016210217A - Knee protection air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a knee protection air bag device of which compactification is achieved, and which can maintain the state that an internal pressure of a chamber for knee protection is high.SOLUTION: The interior of an air bag body 21 is divided into plural chambers by plural partitions (upper partition 26, lower partition 27) having continuous holes 34, 35. A chamber of the plural chambers on a most downstream side in a flow direction of a gas G for expansion constitutes a chamber 31 for knee protection which is extended and expanded in the front of a knee of a crewman. A flow regulation part (valve body 36), which regulates in respect that the gas for expansion in the chamber 31 for knee protection passes through the continuous hole 34 of the upper partition 26 facing the chamber 31 for knee protection and flows toward an adjacent chamber (intermediate chamber 32), is provided. The air bag body 21, the upper partition 26, and the lower partition 27 are respectively formed of a cloth, and are stored in a storage part of a vehicle together with the flow regulation part (valve body 36) in a folded state.SELECTED DRAWING: Figure 3

Description

  TECHNICAL FIELD The present invention relates to a knee protection airbag device that protects an occupant's knee when an impact is applied to a vehicle from the front due to a collision or the like.

  When an impact is applied to the vehicle from the front due to a collision or the like, a knee protecting airbag device is effective in protecting the passenger's knee. This airbag device includes an airbag and an inflator disposed in the airbag. These airbags and inflators are housed in a housing part provided on the instrument panel of the vehicle. When an impact is applied to the vehicle from the front, the inflation gas is ejected from the inflator. With the inflation gas, the airbag pops out of the instrument panel with a part left in the storage portion, and is deployed and inflated with the gap between the instrument panel and the occupant's knee portion obliquely rearward and upward. As a result, an air bag is interposed between the instrument panel and the knee, and the movement of the knee forward is restrained by the airbag and the knee is protected.

  As one aspect of the above-mentioned knee protection airbag device, there is known one in which an outer shell portion of an airbag is constituted by an airbag body, and the inside of the airbag body is partitioned into a plurality of chambers by partition walls having communication holes. ing. In this type of knee protection airbag device, the inflation gas ejected from the inflator is supplied to each chamber, and the chamber is deployed and inflated. In this supply, the inflation gas passes through the communication hole of the partition wall.

  By the way, in the knee protection airbag device in which the airbag main body is partitioned by the partition wall as described above, the inflation gas flows in the communication hole either upstream or downstream in the flow direction of the inflation gas. Distribution is possible. This is detrimental to increasing the internal pressure of the knee protection chamber that restrains the occupant's knee.

  Therefore, for example, as described in Patent Document 1, it is conceivable to provide a check valve in the chamber. In Patent Document 1, as shown in FIG. 14, an airbag body 101 is partitioned into an upstream chamber 103 and a knee protection chamber 104 positioned downstream of the upstream chamber 103 by a partition wall 102 made of a plate material. Yes. The partition wall 102 is provided with a communication hole 105 that allows the upstream chamber 103 and the knee protection chamber 104 to communicate with each other. Further, the partition wall 102 is provided with a check valve 106 that restricts the expansion gas in the knee protection chamber 104 from flowing in the communication hole 105 toward the upstream chamber 103. Therefore, even the small inflator 107 can maintain the internal pressure of the knee protection chamber 104 at a high level.

Utility Model Registration No. 3017153

  However, in the knee protection airbag device described in Patent Document 1, as described above, the partition wall 102 is formed of a plate material and is difficult to deform. Therefore, the airbag device for knee protection must be large in the vehicle width direction and the vertical direction, and requires a large storage portion in the instrument panel.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a knee protection airbag device capable of maintaining a high internal pressure in a knee protection chamber while achieving compactness. It is to provide.

  A knee protection airbag device that solves the above problems includes an airbag main body that is stored in a storage portion provided in a vehicle, and the airbag main body is deployed and inflated with an inflating gas so that the knee portion of the occupant is in front A knee protection airbag device that restrains movement to the knee and protects the knee, wherein the airbag body is partitioned into a plurality of chambers by a single or a plurality of partition walls having communication holes, Of the plurality of chambers, the most downstream chamber in the flow direction of the inflation gas constitutes a knee protection chamber that expands and expands in front of the knee portion of the occupant, and further, the knee protection chamber A flow restricting portion is provided for restricting the inflating gas from flowing toward the adjacent chamber through the communication hole of the partition wall facing the knee protection chamber. The said partition wall is formed by a fabric, respectively, in the folded state, is intended to be received in the receiving portion together with the flow restriction.

  According to said structure, in the case of the accommodation to a storage part, the airbag main body and all the partition which were each formed by the cloth are folded, and it is set as a more compact form than before folding. Therefore, the vehicle does not require a large storage portion.

  When the inflation gas is supplied to the airbag body, the inflation gas flows from the upstream chamber in the flow direction toward the downstream chamber. When the inflation gas moves between adjacent chambers, the inflation gas passes through the communication hole of the partition wall. Then, each chamber is expanded and expanded by the supplied expansion gas. At this time, among the plurality of chambers, the most downstream chamber in the flow direction of the inflation gas is deployed and expanded in front of the occupant's knee as a knee protection chamber. In addition, the flow restricting section restricts the inflation gas flowing into the knee protection chamber from flowing toward the adjacent chamber through the communication hole of the partition wall facing the knee protection chamber, that is, the reverse flow. Is done. Therefore, the internal pressure of the knee protection chamber is kept high. Therefore, the movement of the occupant's knees in response to an impact from the front is restrained by at least the knee protection chamber of the airbag body, and the knees are appropriately protected.

  In the knee protection airbag device, the flow restricting portion is configured by a valve body provided in the knee protection chamber, and the valve body includes a partition wall in which the inflation gas faces the knee protection chamber. When the flow through the communication hole is directed toward the knee protection chamber, an expansion gas flow path is formed between the communication hole and the expansion gas in the knee protection chamber. When trying to flow in the hole toward the adjacent chamber, it is preferable that the hole is deformed so as to approach the partition wall and closes the communication hole.

  According to the above configuration, when the inflation gas tries to flow in the communication hole of the partition wall facing the knee protection chamber toward the knee protection chamber, the communication hole is not blocked by the valve body. . Moreover, an expansion gas flow path is formed between the communication hole and the valve body. Therefore, the inflation gas passes through the communication hole, passes through the flow path between the communication hole and the valve body, and then flows into the knee protection chamber.

  On the other hand, when the inflation gas in the knee protection chamber is about to flow in the communication hole toward the adjacent chamber, the valve body is deformed so as to approach the partition wall. Along with this, the flow path becomes smaller, and the communication hole is blocked by the valve body. The expansion gas in the knee protection chamber is restricted from flowing (backflowing) toward the adjacent chamber.

In the knee protecting airbag device, it is preferable that the flow path formed between the valve body and the communication hole extends along a width direction of the vehicle.
According to the above configuration, when the inflation gas tries to flow in the communication hole of the partition wall facing the knee protection chamber toward the knee protection chamber, the vehicle is interposed between the communication hole and the valve body. A flow path extending along the width direction is formed. Therefore, the inflation gas that has passed through the communication hole flows in the knee protection chamber in the direction along the flow path, that is, in the width direction of the vehicle. The expansion gas expands and expands the knee protection chamber in the vehicle width direction with priority over other directions. As a result, the knee protection chamber quickly reaches the front of the occupant's knee and restrains the forward movement of the knee.

  In the above knee protection airbag device, the valve body is connected to at least one of the airbag main body and the partition wall by a pair of connecting portions extending in the width direction with the communication hole being sandwiched from both sides in the front-rear direction. It is preferable that they are bonded.

  A flow path extending along the width direction of the vehicle between the valve body and the communication hole by being coupled to at least one of the airbag body and the partition wall by the pair of coupling portions as in the above configuration. Is formed.

  In the knee protection airbag device, the flow restricting portion is formed by a valve body protruding from the partition wall toward the knee protection chamber in a state of surrounding the communication hole of the partition wall facing the knee protection chamber. And the inside of the valve body constitutes a flow path for an expansion gas, and the valve body is configured to allow the expansion gas to flow in the communication hole toward the knee protection chamber. When the expansion gas in the knee protection chamber tries to flow toward the adjacent chamber through the communication hole, the tube is deformed so as to close the flow path. It is preferable.

  According to the above configuration, when the inflation gas tries to flow in the communication hole of the partition wall facing the knee protection chamber toward the knee protection chamber, the valve body becomes cylindrical. The expansion gas flow path inside the valve body is opened. Therefore, the inflation gas flows into the knee protection chamber after passing through the communication hole and the flow path.

  On the other hand, when the inflation gas in the knee protection chamber is about to flow in the communication hole toward the adjacent chamber, the valve body is deformed so as to block the flow path. As a result, the inflation gas in the knee protection chamber is restricted from flowing (backflowing) toward the adjacent chamber through the communication hole of the partition wall facing the knee protection chamber.

  A knee protection airbag device that solves the above problems includes an airbag main body that is stored in a storage portion provided in a vehicle, and the airbag main body is deployed and inflated with an inflating gas so that the knee portion of the occupant is in front A knee protection airbag device that restrains movement to the knee and protects the knee, wherein the airbag body is partitioned into a plurality of chambers by a single or a plurality of partition walls having communication holes, Of the plurality of chambers, the most downstream chamber in the flow direction of the inflation gas constitutes a knee protection chamber that expands and expands in front of the knee portion of the occupant, and further, the knee protection chamber The communication hole of the partition wall facing is formed in a shape that opens when the partition wall is in a non-tensioned state and closes when the partition wall is in a tensioned state, and the airbag body and all the partition walls Are respectively formed by the cloth, it is intended to be received in the receiving portion in a folded state.

  According to said structure, in the case of the accommodation to a storage part, the airbag main body and all the partition which were each formed by the cloth are folded, and it is set as a more compact form than before folding. Therefore, the vehicle does not require a large storage portion.

  When the inflation gas is supplied to the airbag body, the inflation gas flows from the upstream chamber in the flow direction toward the downstream chamber. When the inflation gas moves between adjacent chambers, the inflation gas passes through the communication hole of the partition wall. Then, each chamber is expanded and expanded by the supplied expansion gas. At this time, among the plurality of chambers, the most downstream chamber in the flow direction of the inflation gas is deployed and expanded in front of the occupant's knee as a knee protection chamber.

  By the way, during the expansion and expansion of the chamber adjacent to the knee protection chamber, the partition wall facing the knee protection chamber is not in a tension state, and the communication hole of the partition wall is opened. Therefore, the inflation gas flows into the knee protection chamber through the communication hole.

  Then, when the knee protection chamber and the adjacent chamber both expand and expand and the partition wall facing the knee protection chamber is in a tension state, the communication hole of the partition wall is closed. The expansion gas in the knee protection chamber is restricted from flowing toward the adjacent chamber through the communication hole, that is, backflow. Therefore, the internal pressure of the knee protection chamber is kept high. Therefore, the movement of the occupant's knees forward in response to an impact from the front is restrained by at least the knee protection chamber of the airbag body, and the knees are appropriately protected.

In the knee protection airbag device, it is preferable that the communication hole is formed in a slit shape in the partition wall facing the knee protection chamber.
According to the above configuration, the partition wall facing the knee protection chamber is not in a tension state while the chamber adjacent to the knee protection chamber is being expanded and expanded. The communication holes of the partition walls are non-slit, that is, open.

  On the other hand, when both the knee protection chamber and the adjacent chamber expand and expand, and the partition wall facing the knee protection chamber is in a tensioned state, the communication hole of the partition wall is slit-shaped, that is, closed. become.

  According to the knee protection airbag device, the internal pressure of the knee protection chamber can be maintained at a high level while achieving compactness.

It is a figure which shows 1st Embodiment of the airbag apparatus for knee protection, and is a partial side view which shows the airbag apparatus with the vicinity part of a accommodating part, and a passenger | crew's lower limb. The rear view which looked at the airbag module in which the airbag in 1st Embodiment was made into the non-expanding deployment state from back. Sectional drawing which shows the internal structure of the airbag module of FIG. (A) is a sectional side view showing the internal structure of the airbag according to the first embodiment, and (b) is a partial sectional side view showing a part of FIG. (A) is a plane sectional view which shows the internal structure of the airbag in 1st Embodiment, (b) is a partial plane sectional view which expands and shows a part of FIG. 5 (a). The fragmentary perspective view which shows the upper partition in 1st Embodiment, a valve body, and those vicinity parts. In 1st Embodiment, the partial side sectional view which shows the state by which the communicating hole was block | closed with the valve body. It is a figure which shows 2nd Embodiment of the airbag apparatus for knee protection, and is a fragmentary sectional side view which shows an upper partition, a valve body, and those vicinity parts. The fragmentary plane sectional view which shows the upper partition in 2nd Embodiment, a valve body, and those vicinity parts. It is a figure which shows 3rd Embodiment of the airbag apparatus for knee protection, and is a fragmentary sectional side view which shows an upper partition, a valve body, and those vicinity parts. The fragmentary plane sectional view which shows the upper partition in 3rd Embodiment, a valve body, and those vicinity parts. It is a figure which shows 4th Embodiment of the airbag apparatus for knee protection, and is the fragmentary sectional side view which shows the communicating hole of an upper partition, and its vicinity part. The fragmentary plane sectional view which shows the communicating hole of the upper partition in 4th Embodiment, and its vicinity part. The plane sectional view showing the schematic structure of the conventional knee protection airbag device.

(First embodiment)
Hereinafter, a first embodiment embodied in a knee protection airbag device for a vehicle will be described with reference to FIGS.

  In the following description, it is assumed that the traveling direction (forward direction) of the vehicle is the front, the backward direction is the rear, and the height direction is the vertical direction. Moreover, about a vehicle width direction (left-right direction), a direction is prescribed | regulated on the basis of the case where a vehicle is seen from back. In addition, it is assumed that an occupant having the same physique as the collision test dummy is seated in the vehicle.

  As shown in FIG. 1, in the instrument panel 11 of the vehicle 10, a storage portion 13 is provided below the steering column 12. The storage unit 13 stores an airbag module ABM that is a main part of the knee protection airbag device. The airbag module ABM includes an inflator 15 and an airbag 20 as main components.

  As shown in FIGS. 1 to 3, the inflator 15 is for generating an expansion gas G (see FIG. 3). Here, a type of inflator 15 called a pyrotype is employed. The inflator 15 has a substantially cylindrical shape, and a gas generating agent (not shown) that generates the expansion gas G is accommodated therein. The inflator 15 has a gas ejection part 15a at one end (each right side in FIGS. 2 and 3). Further, a harness (not shown) serving as an input wiring for an operation signal to the inflator 15 is connected to the other end of the inflator 15.

  The inflator 15 is a type (hybrid type) in which the partition wall of the high-pressure gas cylinder filled with the high-pressure gas is broken with explosives and the like and the expansion gas G is ejected instead of the pyro type using the gas generating agent. May be used.

An outer shell portion of the airbag 20 is constituted by an airbag body 21.
FIG. 2 shows the airbag module ABM in a state where the airbag main body 21 is deployed in a planar shape without being filled with the inflation gas G (hereinafter referred to as “non-inflated and deployed state”). FIG. 3 shows the airbag module ABM in which the airbag body 21 of FIG. 2 is cut at the center in the front-rear direction in order to show the internal structure of the airbag module ABM.

  The front part of the airbag main body 21 is constituted by a main body cloth part 22, and the rear part is constituted by a main body cloth part 23. Both main body cloth portions 22 and 23 are formed in a shape and size that can protect the region from the shin PD of the occupant P to the knee PK when the airbag main body 21 is deployed and inflated.

  As the main body fabric portions 22 and 23, a woven fabric formed using a material having high strength and flexibility and can be easily folded, for example, polyester yarn, polyamide yarn, or the like is suitable. .

In addition, both the main body cloth parts 22 and 23 may be constituted by one piece of cloth, or may be constituted by a plurality of pieces of cloth.
Both the main body cloth portions 22 and 23 are connected to each other by a peripheral joint portion 24 provided on the peripheral portion thereof. In the first embodiment, most of the peripheral edge coupling portion 24 is formed by sewing (sewing with a sewing thread) a portion other than the upper edge portion of the peripheral edge portions of the two main body cloth portions 22 and 23. This also applies to the lateral coupling portions 28 and 29 and the coupling portions 46 and 47 described later.

  Regarding the above-described sewing, in FIGS. 2, 3 and 6, the sewing portion is expressed by two line types. The same applies to FIG. 9 used to explain the second embodiment. The first line type is a line in which thick lines of a certain length are intermittently arranged and represents a stitch of a sewing thread (see the peripheral joint portion 24 in FIG. 2). The second line type is a line expressed by arranging points at regular intervals, which indicates a cross section of the sewing thread along a cross section passing through the sewing portion (see the peripheral joint portion 24 in FIG. 3).

  The peripheral joint portion 24 may be formed by means different from the sewing using the above-described sewing thread, for example, adhesion using an adhesive. This also applies to the lateral coupling portions 28 and 29 and the coupling portions 46 and 47 described later.

In both the main body cloth portions 22 and 23, a portion surrounded by the peripheral joint portion 24 and the like is an inflatable portion 25 that is expanded and inflated by the inflating gas G.
The inflating part 25 is partitioned into three chambers by a pair of partition walls. Both the partition walls are made of the same material as the two main body cloth portions 22 and 23 and have the same configuration as that generally called a tether. Both the partition walls are disposed at positions spaced apart from each other in the vertical direction between the main body cloth portions 22 and 23. In order to distinguish between the two partitions, the uppermost partition is referred to as an upper partition 26, and the lower partition is referred to as a lower partition 27.

  As shown in FIGS. 4A and 4B and FIGS. 5A and 5B, when the upper partition wall 26 and the lower partition wall 27 are both strained flatly as the expansion portion 25 expands. Further, it is formed in a horizontally long shape in which the dimension in the vehicle width direction is larger than the dimension in the front-rear direction.

  Both end portions of the upper partition wall 26 and the lower partition wall 27 in the vehicle width direction are joined to the main body fabric portions 22 and 23 by the above-described peripheral joint portion 24 (see FIGS. 2 and 3). The upper partition wall 26 is coupled to the corresponding main body cloth portions 22 and 23 by lateral coupling portions 28 provided along the front edge portion and the rear edge portion, respectively. Similarly, the lower partition wall 27 is coupled to the corresponding main body cloth portions 22 and 23 by lateral coupling portions 29 provided along the front edge portion and the rear edge portion, respectively. The upper partition wall 26 and the lower partition wall 27 are bridged between the main body cloth portions 22 and 23 by the above-described coupling.

  In order to distinguish the chamber divided into three by the upper partition wall 26 and the lower partition wall 27, the one located below the lower partition wall 27 is referred to as the lower chamber 33, and is sandwiched between the upper partition wall 26 and the lower partition wall 27. Is referred to as an intermediate chamber 32. Further, the chamber located above the upper partition wall 26 is set so as to expand and expand in front of the knee portion PK of the occupant P (see FIG. 1). It shall be 31.

As shown in FIGS. 1 to 3, the inflator 15 described above is disposed in the lower chamber 33 in a state of extending in the vehicle width direction and is locked to the main body cloth portion 22.
In the lower partition wall 27, communication holes 35 for communicating the lower chamber 33 and the intermediate chamber 32 are formed at locations separated from each other in the vehicle width direction. A communication hole 34 is formed in the upper partition wall 26 at locations spaced apart from each other in the vehicle width direction so that the intermediate chamber 32 and the knee protection chamber 31 communicate with each other. Therefore, the expansion gas G ejected from the inflator 15 flows in the order of the lower chamber 33, the communication holes 35, the intermediate chamber 32, the communication holes 34, and the knee protection chamber 31. In the first embodiment, the communication holes 34 and the communication holes 35 are provided at positions shifted from each other in the vehicle width direction.

  Furthermore, as shown in FIGS. 4 to 6, a flow restricting portion is provided inside the airbag body 21. The flow restricting portion is for restricting the expansion gas G in the knee protection chamber 31 from flowing toward the intermediate chamber 32 through each communication hole 34, that is, backflow. The flow restricting portion is configured by a valve body 36 provided in the vicinity of the communication hole 34 for each communication hole 34 in the upper partition wall 26. Each valve body 36 is formed of the same material as the two main body cloth portions 22 and 23. Each valve body 36 has a dimension slightly longer than the communication hole 34 in the vehicle width direction, and has a dimension longer than that of the upper partition wall 26 in the front-rear direction. Each valve body 36 is coupled to both the airbag main body 21 and the upper partition wall 26 with the communication hole 34 sandwiched from both sides in the front-rear direction. In the first embodiment, this coupling is performed by the above-described lateral coupling portion 28. That is, the front edge portion of each valve body 36 is sandwiched from both the front and rear sides by the front edge portions of the main body cloth portion 22 and the upper partition wall 26, and is laterally coupled to the front edge portions of the main body cloth portion 22 and the upper partition wall 26. Co-sewn by the portion 28. Similarly, the rear edge portion of each valve element 36 is sandwiched from both the front and rear sides by the rear edge portions of the main body cloth portion 23 and the upper partition wall 26, and the rear edge portions of the main body cloth portion 23 and the upper partition wall 26 are lateral to the rear edge portions. Co-sewn by the coupling portion 28.

  As described above, each valve body 36 is coupled to the airbag main body 21 (main body cloth portions 22 and 23) and the upper partition wall 26 by the pair of lateral coupling portions 28, so that each valve body 36 and each communication hole 34 are connected to each other. In the meantime, a flow path 37 extending along the vehicle width direction is formed.

  Incidentally, the airbag module ABM has a compact form (see FIG. 1) by folding the airbag body 21 (see FIGS. 2 and 3) in a non-inflated and deployed state together with the upper partition wall 26 and the lower partition wall 27. Hereinafter referred to as “storage form”). This folding is possible because the airbag body 21, the upper partition wall 26, and the lower partition wall 27 are all formed of cloth, and cannot be performed in the above-mentioned Patent Document 1 in which the partition wall 102 is formed of a plate material. It is. In 1st Embodiment, since each valve body 36 is further formed with the cloth, it is easier to be made into the accommodation form. And the airbag module ABM of the said form for accommodation is accommodated in the said accommodating part 13, and is attached.

  The knee protection airbag device includes an impact sensor 41 and a control device 42 shown in FIG. 1 in addition to the above-described airbag module ABM. The impact sensor 41 includes an acceleration sensor and the like, and detects an impact applied to the vehicle 10 from the front. The control device 42 controls the operation of the inflator 15 based on the detection signal of the impact sensor 41.

Next, the operation of the knee protection airbag device of the first embodiment configured as described above will be described.
When the impact sensor 41 does not detect that an impact has been applied to the vehicle 10 from the front, the controller 42 does not output an operation signal for operating the inflator 15 and the inflation gas G is not ejected. The airbag main body 21 continues to be stored in the storage portion 13 in the storage form (see the solid line in FIG. 1).

  On the other hand, when the vehicle 10 is traveling or the like, an impact of a predetermined value or more is applied to the vehicle 10 from the front due to a collision or the like. An operation signal for operating the inflator 15 is output. In response to this operation signal, the expansion gas G is ejected from the gas ejection portion 15a (see FIGS. 2 and 3) of the inflator 15.

  As shown in FIG. 3, when the inflation gas G is supplied to the airbag main body 21, the inflation gas G flows from the lower chamber 33, which is the most upstream chamber in the flow direction, to the downstream chamber. To the intermediate chamber 32 and the knee protection chamber 31. The expansion gas G in the lower chamber 33 passes through the communication holes 35 of the lower partition wall 27 and flows into the intermediate chamber 32. Further, as shown in FIGS. 3 and 4B, when the expansion gas G in the intermediate chamber 32 tries to flow in the communication holes 34 of the upper partition wall 26 toward the knee protection chamber 31, When each valve body 36 is pressed by the expansion gas G, the valve body 36 is curved upward. Since each valve body 36 is separated upward from the upper partition wall 26, each communication hole 34 is not blocked by the valve body 36. Moreover, a channel 37 extending in the vehicle width direction is formed between each communication hole 34 and the corresponding valve element 36. Therefore, the expansion gas G passes through each communication hole 34 and then on both sides in the vehicle width direction along the flow path 37 as indicated by arrows in FIGS. 3, 5 (b) and 6. It flows toward the knee protection chamber 31.

  Then, the airbag main body 21 is partially accommodated in the airbag main body 21 by releasing (deploying) and inflating the lower chamber 33, the intermediate chamber 32, and the knee protection chamber 31 by the supplied inflation gas G. In the state left in 13, it jumps out from the storage unit 13. As shown by a two-dot chain line in FIG. 1, the airbag body 21 that has popped out is deployed and inflated from the storage portion 13 toward the obliquely rearward and upward direction as a whole. Along with this deployment and expansion, the lower partition wall 27 coupled to the airbag body 21 by the both lateral coupling portions 29 and the upper partition wall 26 coupled to the airbag body 21 by both lateral coupling portions 28 are respectively in the front-rear direction. Pulled to both sides. The lower partition wall 27 and the upper partition wall 26 are each tensioned in a planar shape, thereby restricting the expansion thickness in the front-rear direction of the lower chamber 33, the intermediate chamber 32, and the knee protection chamber 31.

  At this time, the knee protection chamber 31 expands and expands in front of the knee portion PK of the occupant P. In particular, in the first embodiment, the expansion and expansion performed in the vehicle width direction along each flow path 37 is performed with priority over the expansion and expansion performed in other directions, for example, the front-rear direction. . Therefore, the knee protection chamber 31 quickly reaches the front of both knee portions PK of the occupant P.

  In addition, the flow restricting part restricts the expansion gas G flowing into the knee protection chamber 31 from flowing (reversely flowing) toward the intermediate chamber 32 through the communication holes 34 of the upper partition wall 26. That is, as shown in FIG. 7, when the expansion gas G in the knee protection chamber 31 is about to flow in the communication hole 34 toward the intermediate chamber 32, each valve that receives the pressure of the expansion gas G is used. The body 36 is deformed so as to approach the upper partition wall 26. Each deformed valve body 36 reduces each flow path 37 and closes each communication hole 34. The expansion gas G in the knee protection chamber 31 is restricted from flowing toward the intermediate chamber 32 through the communication holes 34. For this reason, the internal pressure of the knee protection chamber 31 that has once increased is suppressed from decreasing due to the backflow to the intermediate chamber 32 and is maintained in a high state. Therefore, the movement of the knee part PK of the occupant P due to the impact from the front of the vehicle 10 is restrained by at least the knee protection chamber 31 of the airbag body 21, and the knee part PK is appropriately protected from the impact. Is done.

According to the first embodiment described in detail above, the following effects can be obtained.
(1) The airbag body 21, the upper partition wall 26, and the lower partition wall 27 are respectively formed of cloth (woven fabric), and are folded and stored in the storage section 13 together with the inflator 15 and the flow restricting section (valve body 36). (FIG. 1).

Therefore, the airbag module ABM can be made compact and the storage portion 13 can be made small.
(2) The inflation gas G in the knee protection chamber 31 flows toward the adjacent chamber (intermediate chamber 32) through the communication hole 34 of the partition wall (upper partition wall 26) facing the knee protection chamber 31. A flow restricting portion for restricting this is provided (FIG. 3).

Therefore, the internal pressure of the knee protection chamber 31 that has been increased by the expansion gas G can be maintained at a high level.
(3) A valve body 36 is provided in the knee protection chamber 31 as a flow restricting portion (FIG. 3).

  Therefore, when the expansion gas G in the intermediate chamber 32 is about to flow through the communication holes 34 toward the knee protection chamber 31, the expansion gas G is interposed between the valve bodies 36 and the communication holes 34. A flow path 37 can be formed (FIG. 4B). Further, when the inflation gas G in the knee protection chamber 31 is about to flow through the communication holes 34 toward the intermediate chamber 32, the valve bodies 36 are deformed so as to approach the upper partition wall 26, thereby communicating with each other. The hole 34 can be closed (FIG. 7).

(4) Each flow path 37 between each valve body 36 and each communication hole 34 is formed so as to extend along the vehicle width direction (FIG. 3).
Therefore, the knee protection chamber 31 can be quickly reached in front of both knee portions PK of the occupant P, and the forward movement of each knee portion PK can be restrained early.

  (5) Each valve body 36 is coupled to the airbag body 21 and the upper partition wall 26 by a pair of coupling portions (lateral coupling portions 28) extending in the vehicle width direction with the communication holes 34 sandwiched from both sides in the front-rear direction. (FIGS. 4A, 4B, and 6).

Therefore, a flow path 37 extending along the vehicle width direction can be easily formed between each valve body 36 and each communication hole 34.
Further, each valve body 36 is coupled to both the upper partition wall 26 and the airbag body 21 by using a lateral coupling portion 28 for coupling the upper partition wall 26 to the airbag body 21.

Therefore, in order to connect each valve body 36 to the upper partition wall 26 and the airbag body 21, it is not necessary to provide a connecting portion separately from the lateral connecting portion 28.
(Second Embodiment)
Next, a second embodiment embodied in a knee protection airbag device for a vehicle will be described with reference to FIGS.

  In the second embodiment, a valve body 45 is used as the flow restricting portion instead of the valve body 36, and the valve body 45 is coupled only to the upper partition wall 26. Further, this coupling is performed by coupling portions 46 and 47 provided separately from the lateral coupling portion 28.

  More specifically, the front edge portion of each valve body 45 is overlapped on the upper partition wall 26 by a coupling portion 46 provided so as to extend in the vehicle width direction in the vicinity of the front of the corresponding communication hole 34. Are combined. Further, the rear edge portion of each valve body 45 is overlapped on the upper partition wall 26 and is coupled to the upper partition wall 26 by a coupling portion 47 provided so as to extend in the vehicle width direction in the vicinity of the rear of the corresponding communication hole 34. ing. A channel 48 extending along the vehicle width direction is formed between each valve body 45 and the corresponding communication hole 34.

Other configurations are the same as those in the first embodiment. For this reason, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.
Accordingly, in the second embodiment, although the target to which each valve body 45 is coupled is different from that of the first embodiment, the valve body 45 acts in the same manner as the valve body 36 of the first embodiment. The effect similar to (5) is acquired.

However, in the second embodiment, in order to connect each valve body 45 to the upper partition wall 26, the lateral coupling portion 28 is not used, so that the coupling portions 46 and 47 are required separately from the lateral coupling portion 28. .
(Third embodiment)
Next, a third embodiment embodied in a vehicle knee protection airbag device will be described with reference to FIGS. 10 and 11.

  In the third embodiment, the flow restricting portion is configured by a valve body 51 that protrudes from the upper partition wall 26 into the knee protection chamber 31 in a state of surrounding each communication hole 34. Each valve body 51 is formed of the same material as the two main body cloth portions 22 and 23. Each valve body 51 may be formed integrally with the upper partition wall 26 or may be formed by a separate member. The interior of each valve body 51 constitutes a flow path 52 for the expansion gas G.

The configuration other than the above is the same as that of the first and second embodiments. Therefore, the same elements as those described in the first and second embodiments are denoted by the same reference numerals, and redundant description is omitted.
Next, the operation of the knee protecting airbag device of the third embodiment will be described.

  When the expansion gas G in the intermediate chamber 32 is about to flow in the communication holes 34 of the upper partition wall 26 toward the knee protection chamber 31, the valve body 51 becomes cylindrical as shown by a solid line in FIG. The flow path 52 is opened. Therefore, the expansion gas G in the intermediate chamber 32 flows through the communication hole 34 and the flow path 52 of the valve body 51 in order, and then flows into the knee protection chamber 31.

  On the other hand, when the inflation gas G in the knee protection chamber 31 is about to flow through the communication holes 34 toward the intermediate chamber 32, the valve body 51 is shown by a two-dot chain line in FIG. It deform | transforms so that the flow path 52 may be plugged up. As a result, the expansion gas G in the knee protection chamber 31 is restricted from flowing toward the intermediate chamber 32 through the flow path 52 and the communication hole 34 in order.

  As described above, in the third embodiment, the configuration of the valve body 51 is different from the configurations of the valve bodies 36 and 45 in the first and second embodiments. In the point which controls the backflow of the gas G for expansion, it is the same as that of 1st and 2nd embodiment.

Therefore, according to the third embodiment, the same effect as the above (1) and (2) can be obtained, and the following effect (6) can be obtained instead of the above (3).
(6) The flow restricting portion is constituted by a valve body 51 that protrudes from the upper partition wall 26 into the knee protection chamber 31 in a state of surrounding each communication hole 34. A flow path 52 connected to the communication hole 34 is formed by the internal space of the valve body 51 (FIG. 10).

  Therefore, when the expansion gas G in the intermediate chamber 32 is about to flow through the communication holes 34 toward the knee protection chamber 31, the valve body 51 can be made cylindrical to open the flow path 52. Further, when the expansion gas G in the knee protection chamber 31 is about to flow through the communication holes 34 toward the intermediate chamber 32, the valve body 51 can be deformed to block the flow path 52.

(Fourth embodiment)
Next, a fourth embodiment embodied in a knee protection airbag device for a vehicle will be described with reference to FIGS. 12 and 13.

  In the fourth embodiment, each communication hole 55 of the upper partition wall 26 is formed so as to open when the upper partition wall 26 is in a non-tensioned state and closed when the upper partition wall 26 is in a tensioned state. As this shape, a slit shape extending in the front-rear direction is employed. In the fourth embodiment, the valve bodies 36, 45, 51 as in the first to third embodiments are not provided.

The airbag main body 21, the upper partition wall 26, and the lower partition wall 27, each formed of cloth, are stored in the storage unit 13 together with the inflator 15 in a folded state.
The configuration other than the above is the same as in the first to third embodiments. For this reason, the same elements as those described in the first to third embodiments are denoted by the same reference numerals, and redundant description is omitted.

  In the fourth embodiment, while the intermediate chamber 32 is being expanded and expanded, the upper partition wall 26 is not in a tensioned state, and each communication hole 55 of the upper partition wall 26 is not in a non-removable state as indicated by a two-dot chain line in FIG. It becomes a slit shape, for example, a state opened in the vehicle width direction. Each communication hole 55 may open in the up-down direction and may have a non-slit shape. Therefore, the expansion gas G in the intermediate chamber 32 flows into the knee protection chamber 31 through each open communication hole 55.

  Then, when both the knee protection chamber 31 and the intermediate chamber 32 are expanded and expanded and the upper partition wall 26 is in a tensioned state, the communication holes 55 of the upper partition wall 26 are closed as indicated by solid lines in FIG. The expansion gas G in the knee protection chamber 31 is restricted from flowing toward the intermediate chamber 32 through the communication holes 55. Therefore, the internal pressure of the knee protection chamber 31 is kept high. Therefore, even if an impact is applied from the front to the vehicle 10 due to a collision or the like, the knee PK of the occupant P moves forward, being restrained by the knee protection chamber 31 having a high internal pressure, and the knee PK is subjected to a collision or the like. Properly protected from impact by.

Therefore, according to the fourth embodiment, the same effect as the above (1) can be obtained, and the following effect can be obtained.
(7) The communication hole 55 of the upper partition wall 26 which is the partition wall facing the knee protection chamber 31 is formed so as to be open when the upper partition wall 26 is in a non-tensioned state and closed when the upper partition wall 26 is in a tensioned state. (FIG. 13).

Therefore, the internal pressure of the knee protection chamber 31 that has been increased by the expansion gas G can be maintained at a high level.
(8) In the upper partition 26, each communication hole 55 is formed in a slit shape (FIG. 13).

Therefore, each communication hole 55 can be opened when the upper partition wall 26 is in a non-tensioned state, and each communication hole 55 can be closed when the upper partition wall 26 is in a tensioned state.
In addition, said each embodiment can also be implemented as a modification which changed this as follows.

<About the storage unit 13>
-The storage part 13 may be provided in front of the passenger | crew's knee part of a passenger seat in the instrument panel 11. FIG. In this case, the accommodating part 13 may be provided in the grab door which opens and closes the opening part of a grab box, for example.

<About the inflator 15>
The inflator 15 may be disposed outside the airbag body 21. However, in this case, the expansion gas G ejected from the inflator 15 needs to be supplied to the lower chamber 33.

<About the chamber>
The airbag body 21 may be divided into four or more chambers by three or more partition walls. Moreover, the airbag main body 21 may be divided into two chambers by a single partition. In any of the above cases, the knee protection chamber 31 is constituted by the most downstream chamber in the flow direction of the inflation gas G.

  The knee portion PK of the occupant P may be restrained and protected by a chamber upstream of the knee protection chamber 31 among the plurality of chambers in the inflating portion 25, for example, the intermediate chamber 32.

<About inflating part 25>
The airbag main body 21 may be substantially entirely composed of the inflating portion 25 as in the above embodiments, but a part of the non-inflating portion that is not inflated without being supplied with the inflating gas G. You may have.

<About the flow control department>
-The valve body 36 in 1st Embodiment is couple | bonded only with respect to the airbag main body 21 (both main body cloth parts 22, 23) among the airbag main body 21 (both main body cloth parts 22, 23) and the upper partition 26. May be. In this case, a coupling portion is provided separately from the lateral coupling portion 28.

The valve bodies 36, 45, 51 may be formed of a material different from the cloth, for example, a sheet body, on condition that the valve bodies 36, 45, 51 can be deformed by the pressure of the expansion gas G.
<About the communication holes 34, 35, 55>
The number and shape of the communication holes 34 and 55 in the upper partition wall 26 may be changed to a number and shape different from those in the above embodiments. The same applies to the communication hole 35 in the lower partition wall 27.

<Others>
In the first to third embodiments, the airbag main body 21, the upper partition wall 26, and the lower partition wall 27 need to be folded when in the storage mode, but the flow restriction portion (valve bodies 36, 45, 51) May be folded or unfolded.

In each of the above embodiments, at least the airbag body 21, the upper partition wall 26, and the lower partition wall 27 may be formed of a nonwoven fabric instead of the woven fabric.
-Vehicles to which the knee protection airbag device is applied include not only private vehicles but also various industrial vehicles.

  The above-described knee protection airbag device can be applied to a knee protection airbag device that is mounted on a vehicle other than a vehicle, for example, an aircraft, a ship, and the like, and protects a passenger's knee from an impact.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle (vehicle), 13 ... Storage part, 21 ... Airbag main body, 26 ... Upper partition, 27 ... Lower partition, 28, 29 ... Lateral coupling part, 31 ... Knee protection chamber, 32 ... Middle chamber, 33 ... Lower chamber, 34, 35, 55 ... communication hole, 36, 45, 51 ... valve body (flow restricting part), 37, 48, 52 ... flow path, 46, 47 ... coupling part, G ... expansion gas, P ... Crew, PK ... knees.

Claims (7)

An airbag main body stored in a storage portion provided in a vehicle is provided, and the airbag main body is deployed and inflated by an inflating gas to restrain the occupant's knee from moving forward to protect the knee. A knee protection airbag device comprising:
The inside of the airbag body is partitioned into a plurality of chambers by a single or a plurality of partition walls having communication holes,
Of the plurality of chambers, the most downstream chamber in the flow direction of the inflation gas constitutes a knee protection chamber that expands and expands in front of the occupant's knee,
Furthermore, a flow restricting portion is provided for restricting the expansion gas in the knee protection chamber from flowing toward the adjacent chamber through the communication hole of the partition wall facing the knee protection chamber,
The airbag apparatus for knee protection, wherein the airbag main body and all the partition walls are each formed of a cloth and are stored in the storage portion together with the flow restricting portion in a folded state. The flow restricting portion is configured by a valve body provided in the knee protection chamber,
When the inflation gas tries to flow in the communication hole of the partition wall facing the knee protection chamber toward the knee protection chamber, the valve body has a flow of the expansion gas between the valve hole and the communication hole. When the expansion gas in the knee protection chamber is about to flow toward the adjacent chamber through the communication hole, it is deformed so as to approach the partition wall and closes the communication hole The knee protection airbag device according to claim 1.   The knee protection airbag device according to claim 2, wherein the flow path formed between the valve body and the communication hole extends along a width direction of the vehicle.   The said valve body is couple | bonded with at least one of the said airbag main body and the said partition by a pair of coupling part extended in the said width direction in the state which pinched | interposed the said communicating hole from the both sides of the front-back direction. Airbag device for knee protection. The flow restricting portion is configured by a valve body protruding from the partition wall toward the knee protection chamber in a state of surrounding the communication hole of the partition wall facing the knee protection chamber,
The inside of the valve body constitutes a flow path for expansion gas,
The valve body is cylindrical when the expansion gas is about to flow in the communication hole toward the knee protection chamber, opens the flow path, and expands in the knee protection chamber. 2. The knee protection airbag device according to claim 1, wherein the air bag device is deformed so as to block the flow path when it is about to flow in the communication hole toward the adjacent chamber. An airbag main body stored in a storage portion provided in a vehicle is provided, and the airbag main body is deployed and inflated by an inflating gas to restrain the occupant's knee from moving forward to protect the knee. A knee protection airbag device comprising:
The inside of the airbag body is partitioned into a plurality of chambers by a single or a plurality of partition walls having communication holes,
Of the plurality of chambers, the most downstream chamber in the flow direction of the inflation gas constitutes a knee protection chamber that expands and expands in front of the occupant's knee,
Further, the communication hole of the partition wall facing the knee protection chamber is formed in a shape that opens when the partition wall is in a non-tensioned state and closes when the partition wall is in a tensioned state,
The airbag body for knee protection, wherein the airbag main body and all the partition walls are each formed of cloth and stored in the storage portion in a folded state.   The knee protection airbag device according to claim 6, wherein the communication hole is formed in a slit shape in the partition wall facing the knee protection chamber.