JP2018052284A - Knee protection airbag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a knee protection airbag which can suppress the block of vent holes caused by a vehicle body side member at deployment and expansion, and can suppress the discharge of expansion gases from the vent holes so that the gases progress toward an occupant side.SOLUTION: A knee protection airbag 26 has a vehicle body side panel part 27 which is arranged at a vehicle body side at the completion of expansion, and an occupant side panel part 28 which is arranged at an occupant side at the completion of the expansion. The knee protection airbag is formed into a bag shape by connecting peripheral edges 27c, 28b of the vehicle body side panel part and the occupant side panel part. The airbag comprises an attachment part 30 and a protection expansion part 40. The vehicle body side panel part and the occupant side panel part are constituted by arranging a connecting part 48 for connecting external peripheral edges and a non-connecting part 49 for maintaining non-connection states of the external peripheral edges at external peripheral edge sides. The non-connecting part is arranged in a region of the protection expansion part, and constitutes vent holes 50L, 50R which can discharge surplus expansion gases which flow into the vent holes.SELECTED DRAWING: Figure 3

Description

  The present invention is folded and stored in a storage part disposed in front of the knee of an occupant seated in a seat, and inflated into the interior, and expands so as to protrude upward from the storage part. In particular, the present invention relates to a knee protection airbag configured to inflate so that the left and right knees of an occupant can be protected.

  Conventionally, as a knee protection airbag, there is a configuration having a vent hole capable of exhausting excess inflation gas flowing into the inside (for example, see Patent Documents 1 to 3).

JP 2003-34215 A JP2003-220920A JP 2006-224776 A

  However, in the knee protection airbag described in Patent Document 1, the vent hole is configured by providing an opening in the panel portion itself constituting the airbag, and for the passenger seat that is inflated when the inflation is completed. It was the structure formed in the area | region which contacts an airbag. For this reason, in the middle of deployment and inflation, the airbag may come into contact with the passenger seat airbag, and the inflation gas may not be exhausted smoothly, and tuning of the gas exhaust amount by the vent hole is not easy. Also, in the knee protection airbags described in Patent Documents 2 and 3, the vent holes are both configured by providing an opening in the panel portion itself constituting the airbag, and the vehicle body side member when the inflation is completed. Since the configuration is arranged at the position on the side, there has been a case where the expansion gas cannot be smoothly exhausted when contacting the vehicle body side member during the expansion and expansion.

  The present invention solves the above-described problems, and can suppress the blockage of the vent hole by the vehicle body side member during expansion and expansion, and can suppress the exhaust of the expansion gas from the vent hole toward the occupant side. An object of the present invention is to provide a knee protection airbag.

The knee protection airbag according to the present invention is folded and stored in a storage portion disposed in front of the knee of an occupant seated in a seat, and an inflation gas is caused to flow into the interior so that the airbag is upward from the storage portion. It is configured to expand so as to protect the left and right knees of the occupant while expanding so as to protrude toward the
The vehicle body side panel portion disposed on the vehicle body side when the inflation is completed and the passenger side panel portion disposed on the occupant side when the inflation is completed, and the outer peripheral edges of the vehicle body side panel portion and the occupant side panel portion are It is a knee protection airbag that is made into a bag shape by being joined,
A mounting portion that is disposed on the lower end side when the inflation is completed and is attached to the storage site side, and a protective inflation portion that is disposed so as to extend upward from the mounting portion when the inflation is completed and protects the occupant from the knee to the shin. With the configuration,
The vehicle body side panel part and the occupant side panel part are configured by arranging, on the outer peripheral edge side, a connecting part in which the outer peripheral edges are connected to each other and a non-joining part that maintains the non-bonded state between the outer peripheral edges.
The non-bonding portion is disposed in the region of the protective expansion portion, and constitutes a vent hole capable of exhausting excess expansion gas flowing into the inside.

  In the knee protection airbag according to the present invention, the vent hole is arranged in the region of the protective inflating portion that protects the occupant from the knee to the shin when the inflation is completed. When the internal pressure rises when it is received, the passenger's knees can be protected smoothly by exhausting excess inflation gas from the vent hole. And since this vent hole is a structure arranged on the outer peripheral edge side of the vehicle body side panel portion and the occupant side panel portion, it can be suppressed from being blocked by the vehicle body side member at the time of deployment and expansion. Even when the internal pressure is increased by contacting the occupant before the completion of the expansion, the expansion gas can be smoothly exhausted, and a further increase in the internal pressure can be suppressed. Further, since the vent hole is configured to exhaust the gas for inflation to the outside so as to be substantially along the vehicle body side panel portion or the passenger side panel portion, the inflation gas is directed toward the passenger side. Exhaust can be suppressed. Furthermore, in the knee protection airbag of the present invention, the vent hole is composed of a non-bonded portion that maintains a non-bonded state between the outer peripheral edges of the vehicle body side panel portion and the occupant side panel portion. At the time of manufacturing the airbag, a vent hole (non-bonded portion) is simultaneously formed by leaving a partially non-bonded region when forming a connecting portion that connects the outer peripheral edges of the vehicle body side panel portion and the occupant side panel portion. Further, the tuning of the gas exhaust amount by the vent hole can be easily set by changing the width dimension of the non-bonding portion.

  Therefore, in the knee protection airbag according to the present invention, it is possible to prevent the vent hole from being blocked by the vehicle body side member during deployment and to suppress the exhaust of the inflation gas from the vent hole toward the passenger. it can.

  In addition, in the knee protection airbag of the present invention, if the vent hole is formed at a position on the upper side of the protection inflatable portion when the inflation is completed, the airbag is almost completely deployed while the folding is eliminated. Since the exhaust of the inflating gas from the vent hole can be suppressed until the air bag is exhausted, it is possible to quickly complete the inflation of the airbag, which is preferable.

  Specifically, the vent hole may be formed at the edge in the left-right direction near the upper end when the expansion is completed, or may be formed at the upper edge when the expansion is completed.

  Further, the vent hole may be formed at the edge on the left and right direction side at a position away from the upper end when the expansion is completed. In such a configuration, for example, closer to the vehicle body side than the normal seating position. In this way, when the adjacent occupant is seated, even if the inflating airbag comes into contact with the adjacent occupant, the inflation gas can be exhausted from the vent hole of the airbag in the middle of inflation. Further, it is preferable because it is possible to suppress a further increase in internal pressure and to suppress pressing of a nearby occupant more than necessary.

It is a schematic longitudinal cross-sectional view along the vehicle front-back direction which shows the vehicle mounting state of the knee protection airbag apparatus which uses the knee protection airbag which is one Embodiment of this invention. It is a general | schematic expanded cross-sectional view along the vehicle left-right direction of the airbag apparatus for knee protection of FIG. It is a rear view which shows the state which expand | deployed flat the knee protection airbag which is one Embodiment of this invention. It is a front view of the airbag of FIG. FIG. 4 is a schematic longitudinal sectional view of the airbag of FIG. 3 and shows a VV portion of FIG. 3. In FIG. 5, it is a partial expanded sectional view which shows the site | part of an attaching part. FIG. 4 is a schematic partially enlarged longitudinal sectional view of the airbag of FIG. 3 and shows a VII-VII portion of FIG. 4. It is a top view which shows the base material which comprises the airbag of FIG. It is a top view which shows the base fabric for tethers which comprises the tether arrange | positioned in the airbag of FIG. In the knee protection airbag device of the embodiment, it is a schematic longitudinal cross-sectional view along the vehicle front-rear direction showing a state of inflation completion of the airbag. In the knee protection airbag device of the embodiment, it is a schematic perspective view showing an inflated completion state of the airbag. It is a rear view which shows the state which expand | deployed flat the knee protection airbag which is other embodiment of this invention. It is a rear view which shows the state which expand | deployed flat the knee protection airbag which is further another embodiment of this invention. It is a rear view which shows the state which expand | deployed flat the knee protection airbag which is further another embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the embodiment, as shown in FIG. 1, a knee protection airbag (hereinafter simply referred to as “airbag”) 26 used in the knee protection airbag device S disposed in front of the passenger seat is taken as an example. And explain.

  The knee protection airbag device S of the embodiment is disposed below the grab box 1 disposed in front of the passenger seat. Note that the vertical, horizontal, and front-rear directions in this specification are the same as the vertical, front-rear, left-right directions of the vehicle on which the knee protection airbag device S is mounted unless otherwise specified.

  As shown in FIGS. 1 and 2, the knee protection airbag device S includes a folded airbag 26, an inflator 17 that supplies inflation gas to the airbag 26, a folded airbag 26, and an inflator 17. And a airbag cover 12 that covers the protruding opening 7 a of the case 7.

  As shown in FIGS. 1 and 2, the case 7 serving as a storage part is disposed on the lower side of the grab box 1 in front of the knee K of the occupant MP. In the lower end side, a substantially box shape is provided in which a projecting opening 7a capable of projecting the airbag 26 is disposed. Specifically, the case 7 includes a substantially rectangular tube-shaped peripheral wall portion 8 whose longitudinal direction is substantially along the left-right direction and whose axial direction is generally along the vertical direction, and a substantially rectangular plate which closes the upper end side of the peripheral wall portion 8. And the lower end side of the peripheral wall portion 8 is configured as a protruding opening 7a. In the case of the embodiment, an attachment hole (not shown) for inserting the attachment bolt 23 of the inflator 17 is formed in the vicinity of the front end of the ceiling wall portion 9. In addition, a plurality of locking claws (not shown) for locking the side wall portion 14 of the airbag cover 12 are provided on the wall portion facing the front and rear direction side of the peripheral wall portion 8 of the case 7 along the left-right direction. Is formed. Further, as shown in FIG. 2, a through-hole (not shown) that can project the right end 18 b side of the inflator 17 is formed in the wall portion disposed on the right side of the peripheral wall portion 8. As shown in FIGS. 1 and 10, the case 7 is connected to a bracket 4 that extends downward from the lower surface side of the front end of the grab box 1 and is attached to the body side. Further, in the embodiment, the rear side of the case 7 is covered with an under cover 3 arranged so as to be continuous from the grab box 1 (see FIGS. 1 and 10).

  The airbag cover 12 is made of a synthetic resin made of a polyolefin-based thermoplastic elastomer or the like, and is configured to cover the protruding opening 7 a of the case 7. Specifically, the airbag cover 12 covers the protruding opening 7a and is opened upward from the peripheral edge of the door portion 13 with one door portion 13 that can be opened forward when the airbag 26 is deployed and inflated. The side wall 14 extends to cover the outer peripheral side of the peripheral wall 8 of the case 7. As described above, the side wall portion 14 is attached to the peripheral wall portion 8 of the case 7 using the locking claw portion (not shown in the figure) formed on the peripheral wall portion 8.

  In the embodiment, as shown in FIG. 2, the inflator 17 is configured to include a main body portion 18 whose outer shape is a substantially cylindrical shape, and a mounting bolt 23 that protrudes from the outer peripheral surface of the main body portion 18. The main body portion 18 is configured so that the axial direction is substantially along the left-right direction side, and a plurality of gas discharge ports 19 for discharging the inflation gas are arranged on one end side (left end 18a side) along the axial direction. The connector 21 having a lead wire 22 extending from the airbag operating circuit is connected to the other end (right end 18b side) protruding from the case 7. The mounting bolts 23 are formed at two locations along the axial direction (left-right direction) of the main body 18. The inflator 17 is stored in the airbag 26 while the right end 18b side to which the connector 21 is connected is exposed to the outside of the case 7 through a through hole formed in the peripheral wall portion 8. The mounting bolt 23 protruding from the ceiling wall portion 9 is protruded from the ceiling wall 9 and fixed to the case 7 together with the airbag 26 by being fastened with a nut 24.

  The airbag 26 is folded and stored in a case 7 serving as a storage portion, and inflated gas is introduced into the airbag 26 so that the airbag 26 projects upward from the case 7, and the left and right knees of the occupant MP. It is set as the structure which expands K so that protection is possible. Specifically, in the case of the embodiment, as shown in FIGS. 3 to 7 and 10, the airbag 26 is disposed on the lower end side when the inflation is completed and is attached to the case 7. 30 and a protective inflating part 40 that is arranged to extend rearward and upward from 30 and protects the occupant MP from the knee K to the shin L. Further, in the case of the embodiment, the airbag 26 is configured to have substantially the same outer shape, and the vehicle body side panel portion 27 arranged on the grab box 1 side (vehicle body side) at the time of completion of inflation, and the occupant MP at the time of completion of inflation. The vehicle body side panel portion 27 and the passenger side panel portion 28 are joined to each other at the outer peripheral edges 27c and 28b to form a bag ( See FIGS. In the embodiment, the outer peripheral edges 27c and 28b of the vehicle body side panel portion 27 and the occupant side panel portion 28 are coupled to each other by an outer peripheral coupling portion 48 (coupling portion) as described later.

  The attachment portion 30 is a portion that is inflated in the case 7 and in a region below the case 7 when the airbag 26 is completely inflated, and the flatly developed shape has a substantially trapezoidal shape with a narrow front edge side. Has been. In the vehicle body side panel portion 27 of the mounting portion 30, there are two mounting holes 27 a through which the mounting bolts 23 of the inflator 17 can be inserted, and an insertion hole 27 b through which a portion on the right end 18 b side of the inflator 17 can be inserted. Is formed. In the case of the embodiment, the vehicle body side panel portion 27 and the occupant side panel portion 28 are connected to each other in the attachment portion 30, and the vehicle body side panel portion 27 and the occupant side panel portion 28 when the airbag 26 is completely inflated. A tether 32 that can regulate the separation distance is provided. The tether 32 is configured as a belt disposed substantially along the left-right direction, and both end sides in the lateral direction (upper end side and lower end side when inflation is completed) are respectively connected to the vehicle body side panel portion 27 and the occupant. The side panel portion 28 is sewn using sutures over substantially the entire left and right regions. In the case of the embodiment, as shown in FIG. 9, the tether 32 is configured by folding a substantially strip-shaped tether base fabric 56 in half on the short direction side, and a fold line of the tether base fabric 56. On the CL, two through holes 32a into which the mounting bolts 23 can be inserted are arranged. The tether 32 is formed with openings 32b, 32c, 32d through which the inflation gas discharged from the inflator 17 can flow out. The opening 32b arranged on the center side in the left-right direction is configured by cutting out the tether 32 in a substantially elliptical shape, and the openings 32c, 32d arranged in the left and right end sides cut out the tether 32 in a substantially semi-elliptical shape. It is configured lacking.

  Moreover, in the airbag 26 of embodiment, as shown to FIGS. 4-6, the auxiliary | assistant expansion | swelling part 34 is formed in the site | part by the side of the passenger | crew side panel part 28 in the rear side of the attachment part 30. FIG. The auxiliary inflating portion 34 is disposed so as to project downward at a position in the vicinity of the rear side of the case 7 when the inflation of the airbag 26 is completed (see FIG. 10), and from the projecting opening 7 a of the case 7. In order to arrange the airbag 26, which is once deployed so as to protrude downward, along the rear surface 1a of the grab box 1 so that the front end (upper end 40a) of the protective inflating portion 40 faces upward when the inflation is completed. In addition, it is provided as a starting point for bending the airbag 26. Specifically, the auxiliary inflating portion 34 is formed by providing a surplus portion 28a on the occupant side panel portion 28 and pinching the surplus portion 28a. From the front and rear ends of the surplus portion 28a, respectively. The front ends of the extending partition tethers 35 and 36 are overlapped with each other and coupled (sewn) to the vehicle body side panel 27 (see FIGS. 5 and 6). That is, in the airbag 26 of the embodiment, when the inflation is completed, the occupant side panel portion 28 disposed on the side away from the grab box 1 increases the membrane length by the amount of the surplus portion 28a that constitutes the auxiliary inflation portion 34. The airbag 26 is configured to be longer than the vehicle body side panel portion 27, and the airbag 26 is formed by combining the front end sides of the partition tethers 35 and 36 extending from the front and rear end sides of the surplus portion 28a in the vehicle body side panel portion 27. It will be bent when the expansion is completed, starting from the site where it is located.

  The auxiliary inflating part 34 is set to have a width dimension in the left-right direction side smaller than a width dimension in the left-right direction side on the front edge side of the mounting part 30 so as to partially protrude as a substantially trapezoidal shape. Is formed. Further, the partition tether 35 disposed on the front side is configured so that the width dimension on the left and right direction side is substantially the same as the width dimension on the left and right direction side of the auxiliary inflating portion 34, and the partition tether 36 disposed on the rear side is The width dimension on the left and right direction side is set larger than that of the front section tether 35, and the airbag 26 is disposed over substantially the entire left and right regions. In the case of the embodiment, each of the partition tethers 35 and 36 is configured by folding a tether base fabric 57 and 58, which will be described later, in half at the center on the short side. Each partition tether 35, 36 is formed with a plurality of gas flow holes 35a, 36a through which the expansion gas flows out along the left-right direction. In the airbag 26 of the embodiment, in the regions on the left and right sides of the auxiliary inflatable portion 34 in the occupant side panel portion 28, the opposing edge portions of the main body base fabric 53 to be described later are directly sewn to each other. (See FIGS. 4 and 7).

  The protective inflating part 40 has a width dimension on the left and right side as a dimension that can protect the left and right knees K of the occupant MP seated in the passenger seat, and a width dimension on the up and down direction on the upper end when the inflation is completed. The size is set so as to be positioned above K, and when the inflating is completed, the rear surface 1a side of the grab box 1 is covered and the occupant MP seated in the passenger seat can be protected from the knee K to the shin L. Yes. In the case of the embodiment, the protective inflating portion 40 is provided with thickness regulation tethers 44 and 45 that connect the vehicle body side panel portion 27 and the occupant side panel portion 28 and regulate the thickness when inflation is completed. By doing so, the expansion completion shape is configured as a substantially plate shape. Two thickness regulation tethers 44 and 45 are arranged side by side in the vertical direction, and are respectively arranged so as to be substantially along the horizontal direction. In the case of the embodiment, the thickness regulation tethers 44 and 45 are formed so as to divide the region of the protective inflating portion 40 over the entire left and right regions. In the embodiment, the protective inflating portion 40 has the thickness regulating tether. The area above 44 is a knee protection area 41 that protects the knee K of the occupant MP, and the area below the thickness regulation tether 44 is a shin protection area 42 that protects the shin L of the occupant MP. The thickness regulating tethers 44 and 45 are configured by folding tether base fabrics 59 and 60, which will be described later, in half at the center on the short side. The thickness regulating tethers 44 and 45 are each formed with six gas flow holes 44a and 45a through which the expansion gas flows out along the left-right direction. Furthermore, in the airbag 26 of the embodiment, the thickness regulating tethers 44 and 45 are arranged substantially along the horizontal direction when the airbag 26 is completely inflated (see FIG. 10), so that the occupant side panel portion 28 is disposed. The connecting part to the side is arranged on the upper end side than the connecting part to the vehicle body side panel portion 27 side.

  The outer periphery coupling portion 48 (coupling portion) disposed on the outer peripheral edge side of the airbag 26 is formed by sewing the outer peripheral edges 27c and 28b of the vehicle body side panel portion 27 and the occupant side panel portion 28 with a suture thread. In the case of the embodiment, except for the upper edge 40b of the protective expansion portion 40 formed by folding back a main body base fabric 54 described later, the protective expansion portion 40 and the mounting portion 30 are outside. It is formed continuously on the periphery (see FIGS. 3 and 4). In detail, in the embodiment, the outer peripheral coupling portion 48 is disposed so as to provide a gap with the upper edge 40 b of the protective expansion portion 40. In other words, the airbag 26 of the embodiment is configured such that the non-bonding portion 49 that maintains the non-bonded state between the outer peripheral edges 27c and 28b is disposed on the upper edge 40b side of the protective inflating portion 40. In the airbag 26 of the embodiment, the non-bonding portion 49 disposed on the upper edge 40b side of the protective inflating portion 40 (the upper side when the air bag 26 is completely inflated) flows into the protective inflating portion 40. The vent holes 50L and 50R that can exhaust the surplus inflation gas G are configured. In the case of the embodiment, the vent holes 50L and 50R are formed in the region of the protective inflating portion 40 at positions that become the left and right edge portions in the vicinity of the upper end 40a at the completion of the inflating. Specifically, in the airbag 26 according to the embodiment, the outer peripheral coupling portion 48 is provided with a gap between the upper edge 40b of the protective inflation portion 40 as shown in FIGS. Terminals 48a and 48b are provided on the lower side away from the upper edge 40b of 40, and a gap (not non-contact) is formed between the upper edge 40b of the protective expansion part 40 and the terminals 48a and 48b of the outer peripheral coupling part 48. The coupling portion 49) constitutes the vent holes 50L and 50R. The vent holes 50 </ b> L and 50 </ b> R are set such that the sum of the opening areas at the time of opening is smaller than the sum of the opening areas of the gas flow holes 44 a formed in the thickness regulating tether 44.

  That is, in the airbag 26 of the embodiment, in the protective inflating portion 40, the region disposed above the thickness regulating tether 44, in other words, disposed on the upper end 40a side when the inflating is completed to protect the knee K of the occupant MP. The vent holes 50L and 50R are disposed on the left edge 41a side and the right edge 41b side of the knee protection area 41 to be exhausted, and the vent holes 50L and 50R exhaust the excess inflation gas G flowing into the knee protection area 41. It is the structure to make. In the case of the embodiment, the vent holes 50L and 50R (non-bonding portions 49) are configured as left-right symmetrical shapes. Further, the terminals 48a and 48b of the outer peripheral coupling portion 48 that constitute the peripheral edges of the vent holes 50L and 50R are substantially arc-shaped in order to suppress damage due to stress concentration during exhaust of the expansion gas from the vent holes 50L and 50R. (See FIGS. 3 and 4).

  In the case of the embodiment, the airbag 26 is formed in a bag shape by cutting a base material made of a woven fabric such as polyester yarn or polyamide yarn into a predetermined shape and sewing it using a suture thread. In the case of the embodiment, as shown in FIGS. 8 and 9, the airbag 26 includes three main body base fabrics 52, 53, and 54 constituting the vehicle body side panel portion 27 and the occupant side panel portion 28 of the airbag 26. And five tether base fabrics 56, 57, 58, 59, 60.

  The base fabric 52 for the main body constitutes, in the vehicle body side panel portion 27, a region from the attachment portion 30 to an arrangement region of the upper thickness regulating tether 44 in the protective expansion portion 40 (a region below the thickness regulating tether 44). Yes. The base fabric 53 for the main body constitutes the occupant side panel portion 28 from the mounting portion 30 to the arrangement region of the upper thickness regulating tether 44 in the protective inflating portion 40 (region below the thickness regulating tether 44). Yes. As shown in FIG. 8, the base fabric 53 for the main body has a surplus portion 53 a constituting the auxiliary expansion portion 34 disposed on the upper and lower central sides, and the left and right sides of the surplus portion 53 a are mutually connected. It is configured to be separated. The main body base fabric 54 constitutes the vehicle body side panel portion 27 and the occupant side panel portion 28 above the thickness regulating tether 44 in the protective expansion portion 40. Each tether base fabric 56, 57, 58, 59, 60 is folded in half to form a tether 32, partition tethers 35, 36, and thickness regulating tethers 44, 45.

  Next, the mounting of the knee protection airbag device S of the embodiment on a vehicle will be described. First, the inflator 17 is housed inside the airbag 26 so that the right end 18b side of the main body 18 protrudes from the insertion hole 27b and the mounting bolt 23 protrudes from the mounting hole 27a. Thereafter, the airbag 26 is rolled and folded from the state where the vehicle body side panel portion 27 and the occupant side panel portion 28 are flattened so as to overlap with each other so as to be wound from the upper edge side upon completion of the inflation to the vehicle body side panel portion 27 side. Then, the bag is folded to a size that can be stored in the case 7, and the folded airbag 26 is wrapped around by a wrapping material (not shown) that can be broken to prevent the bag from collapsing. If the width dimension of the airbag 26 in the left-right direction is larger than the width dimension of the case 7 in the left-right direction, the width dimension on the right-hand side should be reduced as needed so that it can be stored in the case 7 after folding. Wrap it up. At this time, the mounting bolt 23 of the inflator 17 and the right end 18b side of the main body 18 are projected from the wrapping material.

  Next, the folded airbag 26 and the inflator 17 are accommodated in the case 7 such that the mounting bolts 23 of the inflator 17 and the right end 18 b of the main body 18 are protruded from the case 7. Thereafter, the nut 24 is fastened to the mounting bolt 23 protruding from the ceiling wall portion 9, and the inflator 17 and the airbag 26 are attached to the case 7. Then, if the airbag cover 12 is assembled to the case 7, an airbag assembly can be formed. Then, the airbag assembly is attached to the lower surface side of the grab box 1 using the bracket 4, and at the same time, the connector 21 to which the lead wire 22 extending from the airbag operating circuit is connected is protruded from the case 7. If it connects to the right end 18b side of 17 and the under cover 3 is attached, the airbag apparatus S for knee protection can be mounted in a vehicle.

  If an activation signal is input to the inflator 17 after the knee protection airbag device S is mounted on the vehicle, the inflation gas is discharged from the gas discharge port 19 of the inflator 17, and the inflation gas is discharged into the airbag 26. Will flow in. The airbag 26 is inflated to break a wrapping material (not shown), pushes open the door 13 of the airbag cover 12, protrudes from the protruding opening 7a of the case 7, and expands rearward and upward. As shown in the two-dot chain line in FIG. 1 and FIGS. 10 and 11, the expansion is completed so as to cover the rear surface 1 a side of the grab box 1.

  In the airbag 26 of the embodiment, the vent holes 50L and 50R are arranged in the region of the protective inflating portion 40 that protects the occupant MP from the knee K to the shin L when the inflation is completed. When the internal pressure rises when the occupant MP's knee K is received after completion, the surplus inflation gas G is exhausted from the vent holes 50L and 50R, thereby smoothly protecting the occupant MP's knee K. Since the vent holes 50L and 50R are arranged on the outer peripheral edges 27c and 28b of the vehicle body side panel portion 27 and the occupant side panel portion 28, a grab box as a vehicle body side member at the time of expansion and expansion. It is possible to suppress the blockage by 1 and the like, and even if the internal pressure is raised by contacting the occupant MP before the completion of the inflation, the inflation gas can be smoothly exhausted, thereby further increasing the internal pressure. Can be suppressed. Further, the vent holes 50L and 50R are configured to exhaust the expansion gas G to the outside so as to substantially follow the vehicle body side panel portion 27 or the passenger side panel portion 28 as shown in FIG. Therefore, it is possible to suppress the inflation gas G from being exhausted toward the occupant MP side. Furthermore, in the airbag 26 according to the embodiment, the vent holes 50L and 50R are formed from the non-coupling portion 49 that maintains the non-coupling state between the outer peripheral edges 27c and 28b of the vehicle body side panel portion 27 and the occupant side panel portion 28. Therefore, when the airbag 26 is manufactured, it is partially uncoupled when the outer peripheral coupling portion 48 that couples the outer peripheral edges 27c and 28b of the vehicle body side panel portion 27 and the occupant side panel portion 28 is formed. The vent holes 50L and 50R (non-coupled portion 49) can be formed at the same time, and tuning of the gas displacement by the vent holes 50L and 50R also changes the width dimension of the non-coupled portion 49. By doing so, it can be set easily.

  Therefore, in the airbag 26 according to the embodiment, it is possible to prevent the vent holes 50L and 50R from being blocked by the vehicle body side member (grab box 1) during deployment and to go to the occupant MP side from the vent holes 50L and 50R. Exhaust gas can be suppressed.

  Further, in the airbag 26 of the embodiment, the vent holes 50L and 50R are arranged on the upper side of the protective inflating portion 40 when the inflation is completed, specifically, on the position on the upper end 40a side. Since the exhaust of the inflation gas from the vent holes 50L and 50R can be suppressed until the expansion of the bag 26 is substantially completed while the folding of the bag 26 is eliminated, the airbag 26 can be quickly inflated.

  Further, in the embodiment, the main body base fabric 54 constituting the airbag 26 is configured to extend from the upper end side region of the vehicle body side panel portion 27 to the upper end side region of the occupant side panel portion 28. The coupling portion 48 is arranged in a region excluding the upper edge 40b of the protective expansion portion 40, and the vent holes 50L and 50R (non-coupling portion 49) are connected to the left edge 41a side and the right side of the knee protection region 41. It is the structure arranged on the edge 41b side. However, like the airbag 26A shown in FIG. 12, in the case of the configuration in which the outer peripheral coupling portion 62 is arranged over the entire circumference including the upper edge 40b of the protective inflating portion 40A, it is arranged on the upper edge 40b side of the protective inflating portion 40A. It is good also as a structure which arrange | positions the non-joining part 64 (vent hole 65L, 65R) in the right-and-left both edge side of the upper part 63 to be performed. Also in the airbag 26A, the terminals 63a and 63b of the upper portion 63 constituting the peripheral edges of the vent holes 65L and 65R are curved in a substantially arc shape as in the airbag 26 described above. Further, the vent holes 65L and 65R (non-bonding portions 64) are symmetric. Further, as in the airbag 26C shown in FIG. 14, the vent holes 78L and 78R may be arranged in regions on both the left and right edges slightly apart from the upper edge 40b of the protective inflating portion 40C. In the airbag 26C shown in FIG. 14, the vent holes 78L and 78R are formed on the left side portion 75 and the right side portion 76 that are respectively arranged on the left edge 40c side and the right edge 40d side of the protective inflating portion 40C in the outer peripheral joint portion 74. It is comprised from the non-joining part 77 arrange | positioned so that the area | region used as upper end vicinity may be parted. The non-bonding portion 77 is partially formed in the knee protection region 41 </ b> C that is separated from the upper end 40 a of the protective expansion portion 40 </ b> C and is above the upper thickness regulation tether 44. Also in the airbag 26C, the terminals 75a and 75b of the left side portion 75 and the terminals 76a and 76b of the right side portion 76 constituting the periphery of the vent holes 78L and 78R are respectively the same as the airbags 26 and 26A described above. Further, it is curved in a substantially arc shape. The vent holes 78L and 78R are symmetric.

  Further, as in the airbag 26B shown in FIG. 13, the vent holes 71L and 71R may be arranged in a region away from the upper end when the inflation is completed in the protective inflation part 40B. Specifically, in the airbag 26B shown in FIG. 13, the vent holes 71L and 71R are arranged in the shin protection region 42B, and at the outer peripheral coupling portion 67, on the left edge 40c side of the protective inflating portion 40B. It is comprised from the non-joining part 70 arrange | positioned in the upper-lower intermediate part of the left side part 68 and the right side part 69 which are each arrange | positioned at the right edge 40d side. The non-bonding portion 70 is a shin protection region 42B that is separated from the upper end 40a of the protection expansion portion 40B, and more specifically, a portion of the non-connection portion 70 is provided in a region between the thickness regulation tethers 44 and 45 on the upper side of the shin protection region 42B. Is formed. More specifically, the vent holes 71L and 71R (non-bonding portion 70) are disposed in the upper region between the thickness regulating tethers 44 and 45. Also in the airbag 26B, the terminals 68a and 68b of the left side portion 68 and the terminals 69a and 69b of the right side portion 69 constituting the periphery of the vent holes 71L and 71R are respectively the airbags 26, 26A and 26C described above. In the same manner as in FIG. The vent holes 71L and 71R are symmetric.

  In the airbag 26B, since the vent holes 71L and 71R are arranged in the shin protection region 42B separated from the upper end side of the protective inflating portion 40B, for example, the vehicle body side (grab box 1 ), The airbag 26B that protrudes rearward and upward so as to cancel the folding contacts the knee and shin of the adjacent occupant in the middle of inflation. Even in this case, the inflation gas can be exhausted from the vent holes 71L and 71R of the airbag 26B in the middle of inflation, and further increase in internal pressure can be suppressed, and pressing of the adjacent passenger more strongly than necessary can be suppressed. In the airbag 26B shown in FIG. 13, the vent holes 71L and 71R are disposed in the region between the thickness regulating tethers 44 and 45. However, the vent hole may be disposed in the region of the protective inflating portion. For example, the present invention is not limited to this. For example, it may be configured to be arranged in a region between the partition tether 36 and the thickness regulating tether 45.

  In the airbags 26, 26A, 26B, and 26C of the embodiment, the vent holes 50L, 50R, 65L, 65R, 71L, 71R, 78L, and 78R (non-coupling portions 49, 64, 70, and 77) are arranged in the left-right direction. Although it is formed so as to be symmetrical on the edge side, the arrangement position and size of the vent hole (non-bonding portion) are not limited to the embodiment, and are arranged at symmetrical positions. Alternatively, the size may be different on the left and right, or may be arranged only on either the left or right side. Moreover, it is good also as a structure arrange | positioned in the position which becomes a vent hole (non-joining part) the center side of the left-right direction. However, it is preferable to arrange the vent holes symmetrically from the viewpoint of quickly inflating the airbag left and right in a balanced manner, and from the viewpoint of quickly deploying and inflating the airbag to the left and right, the vent It is preferable to arrange the holes on the edge side in the left-right direction.

  DESCRIPTION OF SYMBOLS 1 ... Grab box (vehicle body side member), 7 ... Case (storage part), 12 ... Air bag cover, 17 ... Inflator, 26, 26A, 26B, 26C ... Air bag, 26b ... Upper end, 27 ... Vehicle body side panel part, 27c ... Outer peripheral edge, 28 ... Passenger side panel part, 28b ... Outer peripheral edge, 30 ... Mounting part, 40, 40A, 40B, 40C ... Protective expansion part, 48 ... Peripheral joint part, 49 ... Non-joint part, 50L, 50R ... Bent hole, 62 ... outer periphery coupling portion, 64 ... non-coupling portion, 65L, 65R ... vent hole, 67 ... outer circumference coupling portion, 70 ... non-coupling portion, 71L, 71R ... vent hole, 74 ... outer circumference coupling portion, 77 ... non- Joint part, 78L, 78R ... vent hole, K ... knee, L ... shin, MP ... occupant, S ... airbag device for knee protection.

Claims (5)

Folded and stored in a storage part disposed in front of the knee of the occupant seated in the seat, while allowing the inflation gas to flow into the interior and deploying to protrude upward from the storage part, The left and right knees of the occupant are configured to expand in a protective manner,
A vehicle body side panel portion disposed on the vehicle body side when the inflation is completed, and an occupant side panel portion disposed on the occupant side when the inflation is completed, and an outer periphery of the vehicle body side panel portion and the occupant side panel portion It is a knee protection airbag which is made into a bag shape by combining each other,
An attachment portion that is disposed on the lower end side when the inflation is completed and is attached to the storage site side, and a protective inflation portion that is disposed so as to extend upward from the attachment portion when the inflation is completed and protects the occupant from the knee to the shin And a configuration comprising:
The vehicle body side panel portion and the occupant side panel portion are configured by disposing, on the outer peripheral edge side, a connecting portion in which the outer peripheral edges are connected to each other and a non-connecting portion in which the outer peripheral edges are not connected to each other. And
The knee protection airbag according to claim 1, wherein the non-bonding portion is arranged in a region of the protective inflation portion and constitutes a vent hole capable of exhausting excess inflation gas flowing into the inside.   The knee protection airbag according to claim 1, wherein the vent hole is formed at a position on an upper side of the protective inflating portion when the inflation is completed.   The knee protection airbag according to claim 2, wherein the vent hole is formed at an edge portion on a left and right direction side near an upper end when the inflation is completed.   The knee protection airbag according to claim 2, wherein the vent hole is formed at an upper edge when the inflation is completed.   2. The knee protection airbag according to claim 1, wherein the vent hole is formed at a position away from an upper end at the time of completion of inflation at an edge portion on a left and right side.