SE544247C2 - An airbag with a plurality of inflatable air chambers, arranged side by side, and connected in a state where at least a portion of one of the air chambers overlap one of the other air chambers - Google Patents

Abstract

There is provided an airbag that can obtain an appropriate protection performance with a simple configuration. Airbag (10) is inflated by an introduced gas and protects head (A) of an occupant. Airbag (10) includes bag-shaped airbag main body section (12). In bag-shaped airbag main body section (12), a plurality of air chambers (19), into each of which the gas is introduced, are arranged side by side. In airbag main body section (12), air chambers are connected in a state where at least a part of one air chambers (19) and at least a part of each of the other air chambers (19) overlap each other.

Description

Technical Field id="p-1"

[0001] The present invention relates to an airbag that protects a head of an occupant.

Background Art id="p-2"

[0002] In the related art, a head protection airbag apparatus that covers and protectsa head of an occupant of a tWo-Wheeled vehicle such as a bicycle, or covers and protects ahead of an occupant seated in a seat of an automobile is known as an airbag apparatusincluding an airbag that inflates and deploys as a gas is introduced. For example, anairbag main body section used in such an airbag apparatus includes a plurality oflongitudinal air chambers, and the air chambers are arranged side by side. The airbagmain body section is made such that side portions of the air chambers are connected toeach other to form an inflated shape along the roundness of the head of the occupant,and covers a portion ranging from a back of the head to a forehead including both sides of the head in the inflated shape (for example, refer to PTL 1).

Citation ListPatent Literature[0003] PTL 1 Japanese Translation of a PCT Application Laid-Open No. 2013-540209 (Page 6-12, FIG. 2) Summary of Invention Technical Problem id="p-4"

[0004] HoWever, since a non-inflating section exists between the adjacent airchambers in the airbag, it is necessary to take measures such as additionally providinga structure for complementing the non-inflating section or making a configuration of abase cloth more complicated. Thus, it is difficult to reduce manufacturing costs. id="p-5"

[0005] The present invention is devised in vieW of such points, and an object thereof isto provide an airbag that can obtain an appropriate protection performance With a simple configuration.

Solution to Problem id="p-6"

[0006] According to Claim 1, there is provided an airbag that is inflated by anintroduced gas to protect a head of an occupant. The airbag includes a bag-shapedairbag main body section. In the airbag main body section, a plurality of air chambers,into each of Which the gas is introduced, are arranged side by side, and are connected in 'taïsoï am-ixätioi: of one of the air a state Where at least a part oil' a afšoih at-:ïm noi-“ëtifliisi of one of the chambers and at least a part oil' cftaïwlfši: <'_~:o.i1's.i:f=_'i.aä 1* 21:: iother air chambers overlap each other.[0007] According to Claim 2, in the airbag of Claim 1, in the airbag main body section, tip sides of the one air chamber and the other air chambers, Which are adjacent to each other, are fixed and connected to each other. id="p-8"

[0008] According to Claim 3, in the airbag of Claim 1 or 2, in a state Where tWo-æšt-sïe-:v arg; positioned With the one air chamber i;ít;..:~;j::1::'ïiÉ ítzicç; air chambers» overlap the one air chamber in the airbag main body section, tip sides ofthe one air chamber and the tWo~~«~:s=':§~ix\<@§= air chambers are fixed and connected to eachother. id="p-9"

[0009] According to Claim 4, in the airbag of Claim 3, the airbag main body section æëxfl air chambers and a includes a side edge joining section that joins both of the»~:^reinforcement section that protects the side edge joining section from a load from theone air chamber to at least one of the tWo--scsëašaiëf- air chambers, Which accompaniesinflation of the airbag main body section. id="p-10"

[0010] According to Claim 5, in the airbag of Claim 4, the side edge joining section and the reinforcement section each are a seWing section formed of a seWing thread, and the .iaß, reinforcement section eXtends maa .íw :än-Li Advantageous Effects of Invention id="p-11"

[0011] In the airbag of Claim 1, since the air chambers are connected in a state Whereat least a part of one air chamber and at least a part of each of the other air chambersoverlap each other, a portion between the adjacent air chambers is complemented bybeing covered through the overlapping of the air chambers, and thus an appropriateprotection performance can be obtained With a simple configuration. id="p-12"

[0012] In the airbag of Claim 2, in addition to an effect of the airbag of Claim 1, since the tip sides of one air chamber and the other air chambers, Which are adjacent to each other, of the airbag main body section are fixed and connected to each other, the tipsides come to a shrunk state With respect to a base end side, and the adjacent airchambers push each other due to the inflation of each other, thereby applying a load inan inflating direction at positions of overlapping each other. Accordingly, the airbagmain body section curves in accordance With the shape of the head of the occupant, andan occupant's head protection performance can be improved. id="p-13"

[0013] In the airbag of Claim 3, in addition to an effect of the airbag of Claim 1 or 2,since the tip sides of the one air chamber and both of the other air chambers are fixedand connected to each other in a state Where the other air chambers of the airbag mainbody section, Which are positioned With one air chamber interposed therebetWeen,overlap the one air chamber, a perimeter Where tension occurs can be made integrallycontinuous and long. Thus, reaction force can be made stronger Without increasing aninternal pressure and the occupant's head protection performance can be improved.[0014] In the airbag of Claim 4, in addition to an effect of the airbag of Claim 3, by thereinforcement section protecting the side edge joining section from the load from the oneair chamber to the other air chambers, Which accompanies the inflation of the airbagmain body section, the side edge joining section can be reliably prevented from beingdamaged at the time of inflation of the airbag main body section While maintaining theperimeter of the airbag main body section, and an appropriate protection area can beobtained. id="p-15"

[0015] In the airbag of Claim 5, in addition to an effect of the airbag of Claim 4, byforming the side edge joining section and the reinforcement section as the seWingsections formed of the seWing threads and forming the reinforcement section along the direction intersecting the side edge joining section, the reinforcement section can effectively receive the load from the one air chamber to the other air chambers, Whichaccompanies the inflation of the airbag main body section, and the side edge joiningsection can be reliably prevented from being damaged due to rupture of the seWing thread caused by this load.

Brief Description of DraWings[0016] FIG. 1 is a side view illustrating an airbag according to Embodiment 1 of thepresent invention; FIG. 2 is a sectional view of the airbag in an inflated and deployed state, Whichis taken at a position corresponding to I-I in FIG. 1; FIG. 3 is a plan view iIIustrating a state of a base c1oth of the airbag; FIGS. 4A to 4G are explanatory views illustrating a manufacturing process ofan airbag main body section of the airbag, and FIG. 4D is a sectional view taken at aposition corresponding to II-II in FIG. 4G; FIG. 5 is a side view illustrating an airbag according to Embodiment 2 of thepresent invention; FIG. 6 is a sectional view of the airbag in an inflated and deployed state, Whichis taken at a position corresponding to III-III in FIG. 5; FIGS. 7A to 7G are explanatory views illustrating a manufacturing process ofan airbag main body section of the airbag, and FIG. 7D is a sectional view taken at aposition corresponding to IV-IV in FIG. 7G; and FIG. 8A is a side view illustrating an airbag in an inflated and deployed state according to Embodiment 8 of the present invention, and FIG. SB is an enIarged side view illustrating a part of FIG. 8A.

Description of Embodiments id="p-17"

[0017] Hereinafter, Embodiment 1 of the present invention Will be described withreference to the drawings. id="p-18"

[0018] In FIGS. 1 and 2, the reference sign 10 indicates an airbag. An airbagapparatus including this airbag 10 is a head protection airbag apparatus that protectshead A of an occupant of a bicycle or the like, which is a moving body. In theembodiment, the airbag apparatus is, for example, an airbag apparatus for atwo-wheeled vehicle, which is mounted in the vicinity of a neck of the occupant.Hereinafter, description will be made based on each of a front-and-rear direction (anarrow FR direction and an arrow RR direction), a right-and-left direction (an arrow Ldirection and an arrow R direction), and an up-and-down direction (an arrow Udirection and an arrow D direction), which are set with a state where the occupant hasmounted the airbag apparatus as reference. id="p-19"

[0019] Since this airbag apparatus can also be called as an airbag module, the airbagapparatus includes an inflator that supplies a gas to airbag main body section 12, acontrol section that controls operation of the inflator, and a battery (secondary battery),which is a power supply of the inflator and the control section, in addition to airbag 10having airbag main body section 12 which is a bag-shaped outer shell section. Airbag10 (airbag main body section 12), which is in a folded state through a predeterminedmethod, the inflator, the control section, and the battery are accommodated, for example,inside a fabric cover, and the airbag apparatus is mounted by being wrapped in the vicinity of the neck of the occupant. id="p-20"

[0020] The inflator includes a disk-shaped or cylindrical main body portion. Anigniter and a chemical are accommodated inside the main body section. An electricsignal from the control section, Which is transmitted via a connector connected thereto,causes the igniter to combust the chemical, and a gas for inflation is rapidly suppliedinto airbag main body section 12 from a gas ejection port formed in the main bodysection. id="p-21"

[0021] The control section includes a sensor that detects impact and a controlapparatus. The control apparatus is connected to the inflator via a signal line, andoperates the inflator When the sensor detects predetermined impact. id="p-22"

[0022] Airbag main body section 12 is formed in a bag shape as a Whole by combiningand joining a single, or a plurality of base cloths through seWing, bonding, or Welding.That is, airbag main body section 12 may be a so-called one-piece Woven (OPW) airbagformed by Weaving one base cloth, or may be an airbag formed in a bag shape by joiningtWo or more base cloths through seWing. In addition, airbag main body section 12includes gas introduction section 15 into Which a gas is introduced from the inflator,inflating section 16 that inflates due to the gas introduced from gas introduction section15, and non-inflating section 17 into Which the gas is not introduced. Airbag mainbody section 12 is joined by joining section 18 formed through seWing, and is formed tohave a helmet-like three-dimensional shape that covers the head from the vicinity of theneck of the occupant in an inflated and deployed state. For example, joining section 18of the embodiment is a seWing section formed of a seWing thread. id="p-23"

[0023] Gas introduction section 15 is formed as an opening portion. Gas introduction section 15 is a s that becomes a deployment base end side of airbag main body section 12.

In the embodiment, gas introduction section 15 is positioned at the rear of the vicinity of the neck of the occupant. For example, a part of the main body section of the inflatormay be inserted in gas introduction section 15. id="p-24"

[0024] Inflating section 16 includes a plurality of air chambers (chambers) 19 thatinflate due to the introduction of a gas from gas introduction section 15. In addition,gas guide sections 20 (FIG. 3) that control the flow of the gas, Which is introduced intoair chambers 19, are formed in inflating section 16. id="p-25"

[0025] A plurality of first air chambers 22 that extend along the right-and-leftdirection and a plurality of second air chambers 23 that extend radially are set in airchambers 19. id="p-26"

[0026] Each of first air chambers 22 is an air chamber into Which a gas is directlyintroduced from gas introduction section 15 via the inflator. Each of first air chambers22 is longitudinally formed in the right-and-left direction, and protrudes to the right orto the left from gas introduction section 15. Respective first air chambers 22 arepositioned to Wrap the vicinity of the neck of the occupant such that respective tip sidesoppose each other at positions in front of the neck of the occupant, thereby protectingthe neck of the occupant in an inflated and deployed state. id="p-27"

[0027] Respective second air chambers 23 are positioned above each first air chamber22, and are arranged side by side on the right and the left. In the embodiment,respective second air chambers 23 are arranged, for example, symmetrically on theright and the left. In the embodiment, three second air chambers 23 are formed oneach of both right and left side portions, and one second air chamber is formed in amiddle portion. The three second air chambers Will be described as second airchambers 23a to 23c and the one second air chamber Will be described as second air chamber 23d. HoWeVer, the number or the shape of the second air chamber is not limited. In addition, each of second air Chambers 23 spreads open in a so-called fingershape such that a distance between edge portions gradually increases from a base endside (lower side) toward a tip side (upper side) thereof, for example, in a state where thebase cloth is yet to be joined by joining section 18 (FIG. 3). In the embodiment, in astate of being joined by joining section 18, second air chambers 23 are connected in astate where at least a part of one second air chamber 23 and at least a part of anothersecond air chamber 23 overlap each other. More specifically, second air chambers 23 ofthe embodiment are connected such that tip sides of one second air chamber 23 andanother second air chamber 23, which are adjacent to each other, are fixed by joiningsection 18. In a case of the embodiment, as illustrated in FIG. 2, one edge portions(upper edge portions) of second air chambers 23a and 23b positioned on the right andthe left and the other edge portions (lower edge portions) of second air chambers 23band 23c overlap each other such that the other edge portions are, in turn, positioned onouter sides (upper sides) of one edge portions. The other edge portions (lower edgeportions) of second air chambers 23c and second air chamber 23d overlap each other onboth sides of second air chamber 23d. For this reason, in an inflated and deployedstate, each of second air chambers 23 protects a position ranging from a back portion toboth side portions and a front portion of head A of the occupant. id="p-28"

[0028] Gas guide sections 20 lead a gas, which is introduced from gas introductionsection 15, to air chambers 19. Gas guide sections 20 can be disposed at any positionsin airbag main body section 12. id="p-29"

[0029] Non-inflating section 17 is formed in a fin shape along an outer edge of each ofair chambers 19 of inflating section 16 in a state where the base cloth is yet to be joined by joining section 18. Non-inflating section 17 of the embodiment is formed, for example, as joining allowance (seam allowance) for air Chambers 19 in the base cloth.Non-inflating section 17 is positioned along a tip side and a side edge portion of each ofair Chambers 19. That is, non-inflating section 17 is positioned along the tip side andthe side edge portion of each first air chamber 22 and each second air chamber 23.[0030] Joining section 18 is formed, for example, through sewing, and finalizes aposition of non-inflating section 17 on the tip sides of second air chambers 23. In theembodiment, for example, in a state where second air chambers 23 (second air chambers23a to 23d) are arranged side by side on the right and the left to overlap a part of eachother as illustrated in FIG. 4B after a state of the base cloth illustrated in FIG. 4A,joining section 18 is formed by joining the tip sides of the plurality of second airchambers 23 through sewing as illustrated in FIG. 4G. For this reason, as illustratedin FIG. 4D, joining section 18 allows a part of each of adjacent second air chambers 23 tobe formed to overlap each other in the right-and-left direction and the up-and-downdirection, and allows a part of each of adjacent second air chambers 23 to cover aposition of non-inflating section 17 between adjacent second air chambers 23. Morespecifically, adjacent second air chambers 23 are arranged side by side whileoverlapping each other in a diagonal direction from a top of the head to both sideportions of the head of the occupant in airbag main body section 12. Thus, airbag mainbody section 12 is disposed to have a three-dimensional shape. That is, second airchambers 23 are arranged to overlap each other such that the deployment tip side ofairbag main body section 12 shrinks. id="p-31"

[0031] To describe the outline of the airbag apparatus, if the sensor detectspredetermined impact when a collision of the two-wheeled vehicle occurs, the control apparatus operates the inflator, and causes the inflator to eject a gas. Then, the gas ejected from the inflator floWs into airbag main body section 12 from gas introductionsection 15, and is introduced into each of first air chambers 22 and second air chambers23 by gas guide section 20. By airbag main body section 12 inflating and deployingfrom a folded state, the airbag main body section ruptures a part of the cover at adeployment pressure and protrudes, thereby covering head A from the back of the headto the forehead of the occupant. id="p-32"

[0032] At this time, since second air chambers 23 are arranged such that at least apart of each of adjacent second air chambers overlap each other, non-inflating section 17between adjacent second air chambers 23 is complemented by being covered throughthe overlapping of second air chambers 23, and thus the generation of a portion Where aprotection stroke becomes small is suppressed. Consequently, an appropriateprotection performance Which enables effective protection of head A of the occupantWith a simple configuration can be obtained. id="p-33"

[0033] In addition, since second air chambers 23, Which are adjacent to each other, ofairbag main body section 12 are fixed and connected to each other such that the tipsides thereof are fixed by joining section 18, the tip sides come to a shrunk state Withrespect to the base end side, and adjacent second air chambers 23 push each other dueto the inflation of each other, thereby applying a load in an inflating direction atpositions of overlapping each other. Accordingly, airbag main body section 12 curves inaccordance With the shape (roundness) of head A of the occupant. For this reason, theprotection performance of head A of the occupant can be improved and an increase inthe capacity of each of air chambers 19 (second air chambers 23) can be suppressed.Thus, an inflator having a small output can be used as the inflator that supplies a gas to airbag main body section 12, and thus it becomes possible to achieve miniaturization and Weight reduction. Although a gap between the base end sides of second airChambers 23 before inflation is generated in some cases, the gap can be eliminated bysecond air chambers 23 pushing each other With the load applied in the inflatingdirection in an inflated state since the tip sides of adjacent second air chambers 23 aresimply fixed by joining section 18. Therefore, the generation of the portion Where aprotection stroke becomes small can be easily suppressed by simply splitting airchambers 19 at the time of cutting the base cloth, forming joining section 18 throughsimple seWing, and fixing only the tip sides of adjacent second air chambers 23.Consequently, an occupant protection performance can be improved While suppressingan increase in manufacturing costs. id="p-34"

[0034] Next, Embodiment 2 Will be described With reference to FIGS. 5 to 7D. Thesame configurations and effects as Embodiment 1 Will be assigned With the samereference signs, and description thereof Will be omitted. id="p-35"

[0035] Airbag 10 of the embodiment is an airbag, in Which second air chambers 23 ofair chambers 19 of airbag main body section 12 are connected such that in a state Wherethe other second air chambers 23, Which are positioned With one second air chamber 23interposed therebetWeen, overlap one second air chamber 23, the tip sides of one secondair chamber 23 and both of other second air chambers 23 are fixed. id="p-36"

[0036] Airbag main body section 12 in the embodiment is formed of a base cloth Whichis basically the same as Embodiment 1. ln a state Where second air chambers 23a and23c, between Which second air chamber 23b is interposed, overlap both sides of secondair chamber 23b, side edge portions of second air chambers 23a and 23c are fixed by sideedge joining section 25 at the position of non-inflating section 17, for example, through seWing, and the tip sides of second air chambers 23a to 23c are fixed and connected by joining section 18 at the position of non-inflating section 17. For example, side edgejoining section 25 of the embodiment is a seWing section formed of a seWing thread.Side edge joining section 25 is formed along a direction intersecting joining section 18. id="p-37"

[0037] For example, from a state of the base cloth illustrated in FIG. 7A, a part of eachof the other second air chambers 23 (second air chambers 23a and 23c), between Whichone second air chamber 23 (second air chamber 23b) is interposed, is caused to overlapone second air chamber 23 (second air chamber 23b) and the side edge portions opposingeach other of the other second air chambers 23 (second air chambers 23a and 23c) arejoined through seWing, thereby forming side edge joining section 25, as illustrated inFIG. 7 B. As illustrated in FIG. 7 C, the tip sides of one second air chamber 23 (secondair chamber 23b) and both of the other second air chambers 23 (second air chambers 23aand 23c) are joined through seWing, thereby forming joining section 18. For thisreason, joining section 18 and side edge joining section 25 allow the plurality of othersecond air chambers 23 (second air chambers 23a and 23c) to be formed such that a partthereof overlaps one second air chamber 23 (second air chamber 23b) Which ispositioned therebetWeen as illustrated in FIG. 7D, and allow the position ofnon-inflating section 17 between the other second air chambers 23 (second air chambers23a and 23c) to be covered by a part of one second air chamber 23 (second air chamber23b). More specifically, the second air chambers are arranged side by side along bothside portions of the head to overlap each other in the diagonal direction such that onesecond air chamber 23 (second air chamber 23b) is positioned on a so-called inner sideWhich is close to head A of the occupant, and the other second air chambers 23 (secondair chambers 23a and 23c) are positioned on an outer side opposite to head A With respect to one second air chamber 23 (second air chamber 23b). Thus, airbag main body section 12 has a three-dimensional shape. That is, second air Chambers 23 arearranged to overlap each other such that the deployment tip side of airbag main bodysection 12 shrinks. id="p-38"

[0038] To describe the outline of the airbag apparatus, if the sensor detectspredetermined impact When a collision of the tWo-Wheeled vehicle occurs, the controlapparatus operates the inflator, and causes the inflator to eject a gas. Then, the gasejected from the inflator floWs into airbag main body section 12 from gas introductionsection 15, and is introduced into each of first air chambers 22 and second air chambers28 by gas guide section 20. By airbag main body section 12 inflating and deployingfrom a folded state, the airbag main body section ruptures a part of the cover at adeployment pressure and protrudes, thereby covering head A from the back of the headto the forehead of the occupant. id="p-39"

[0039] At this time, since second air chambers 23 are connected such that the tip sidesof second air chamber 28b and both of second air chambers 23a and 23c are fixed in astate Where second air chambers 23a and 23c, Which are positioned With second airchamber 28b interposed therebetWeen, overlap second air chamber 23b, outer perimeterLN of airbag main body section 12 Where tension occurs can be made integrallycontinuous and long. By a load of pushing outer second air chambers 23a and 23c thatoverlap second air chamber 23b being generated at a position between second airchambers 23a and 23c from inner second air chamber 28b at the time of inflation,second air chambers 28a and 23c are pushed in a direction of protruding outWards at aposition Where the side edge portions oppose each other (side edge joining section 25).For this reason, since outer tension can be increased in airbag main body section 12, reaction force against an interference that comes into contact With an outer side of airbag main body section 12 can be increased only by simple fixing of air chambers 19Without increasing internal pressures of air chambers 19 (inflating section 16) ormaking air chambers 19 (inflating section 16) large, that is, Without increasing theoutput of the inflator. Therefore, an appropriate protection performance Which enableseffective protection of head A of the occupant With a simple configuration can beobtained. id="p-40"

[0040] In addition, by side edge joining section 25 fixing the side edge portions ofsecond air chambers 28a and 28c, each of Which having a part overlapping second airchamber 23b, stronger tension can occur, the protection performance can be improved,and Workability When fixing the tip sides of second air chambers 23a to 28c at the timeof manufacturing can be improved. id="p-41"

[0041] Next, Embodiment 8 Will be described With reference to FIGS. 8A and 8B. Thesame configurations and effects as each embodiment Will be assigned With the samereference signs, and description thereof Will be omitted. id="p-42"

[0042] Airbag 10 of the embodiment includes reinforcement section 28 that protectsside edge joining section 25 of Embodiment 2 from a load from second air chamber 28bto second air chambers 28a and 28c, Which accompanies the inflation of airbag mainbody section 12. id="p-48"

[0048] That is, as illustrated in FIGS. 8A and 8B, reinforcement section 28 reinforcesside edge joining section 25 that joins the plurality of second air chambers 28a and 23cthat overlap each other on an outer side of second air chamber 23b, Which is an oppositeside to head A of the occupant, With second air chamber 28b interposed therebetWeen.Reinforcement section 28 is a seWing section formed of a seWing thread as side edge joining section 25, and reinforcement section 28 of the embodiment is an extended sewing section formed by extending the sewing thread configuring side edge joiningsection 25. That is, reinforcement section 28 and side edge joining section 25 areformed of the same sewing thread. In the embodiment, reinforcement section 28 isdisposed in non-inflating section 17 positioned on the side edge portions of second airchambers 28a and 23c. For example, reinforcement section 28 is formed to extend in apart of non-inflating section 17 in which side edge joining section 25 is formed.Reinforcement section 28 may be formed in a portion of non-inflating section 17, inwhich side edge joining section 25 is positioned to overlap each other, or may extend in aportion of non-inflating section 17, in which the reinforcement section and the side edgejoining section do not overlap each other. Reinforcement section 28 is connected to sideedge joining section 25 and is formed along a direction intersecting side edge joiningsection 25. Reinforcement section 28 eXtends from an end portion of side edge joiningsection 25 to the upper side, that is an upper rear side in the embodiment, innon-inflating section 17 at second air chamber 28c positioned on the upper side. id="p-44"

[0044] Then, when a gas ejected from the inflator flows into airbag main body section12 from gas introduction section 15, and is introduced into each of first air chambers 22and second air chambers 23 by gas guide sections 20, in second air chambers 23a, loadof pushing outer second air chambers 28a and 23c, which overlap second air chamber23b, from inner second air chamber 28b at the time of inflation is generated at aposition between second air chambers 23a and 23c. Therefore, a load whichaccompanies the inflation of airbag main body section 12 is generated from second airchamber 28b toward a direction of separating second air chambers 28a and 23c awayfrom each other (arrow F direction), that is, the direction intersecting side edge joining section 25, in other words, a direction of shearing the sewing thread configuring side edge joining section 25. That is, a load of second air Chambers 23a and 23b of airbagmain body section 12 returning to an original shape in response to the regulation of sideedge joining section 25 and a load along the same direction are generated. Byreinforcement section 28 being formed to eXtend along the direction intersecting sideedge joining section 25, the load is effectively received by the entire reinforcementsection 28, and the load is prevented from concentrating on only a rear end portion ofside edge joining section 25. By reinforcement section 28 protecting side edge joiningsection 25 from the load from second air chamber 23b to second air chambers 23a and23c, Which accompanies the inflation of airbag main body section 12, in such a manner,load capacity can be improved, and side edge joining section 25 can be reliablyprevented from being damaged at the time of inflation of airbag main body section 12 While maintaining perimeter LN of airbag main body section 12. That is, the seWing thread of side edge joining section 25 can be prevented from shearing caused by the load.

For this reason, an appropriate protection area of airbag main body section 12 can beobtained by side edge joining section 25. id="p-45"

[0045] In addition, since reinforcement section 28 is formed by being connected to sideedge joining section 25 by the seWing thread configuring side edge joining section 25, itis possible to form the reinforcement section by extending this seWing section Whenforming side edge joining section 25, costs are unlikely to be high since manufacturing iseasy, and it is possible to easily improve load capacity. id="p-46"

[0046] Although at least a part of each of second air chambers 23a and 23c, betweenWhich one second air chamber 23b is interposed, overlaps second air chamber 23b inEmbodiments 2 and 3, for example, at least a part of each of the plurality of second air chambers 23, between Which the plurality of adjacent second air chambers 23 are interposed, may overlap the plurality of adjacent second air Chambers 23, or also secondair Chambers 23, between Which the plurality of second air chambers 23 are interposed,may overlap a plurality of second air chambers at once instead of one second airchamber. That is, in an inflated state of airbag main body section 12, there may be tWoor more second air chambers 23 positioned on the inner side and tWo or more second airchambers 23 positioned on the outer side. id="p-47"

[0047] In addition, the airbag apparatus of each Embodiment can also be used as, forexample, an airbag apparatus disposed in a headrest positioned at the rear of head A of the occupant seated in a seat of an automobile.

Industrial Applicability[0048] The present invention can be suitably used, for example, as a head protection airbag apparatus for a tWo-Wheeled vehicle.

Reference Signs List id="p-49"

[0049] airbag 12 airbag main body section19 air chamber side edge joining section28 reinforcement section A head

Claims (5)

PROPOSED CLAIM AMENDMENT

1. An airbag (10) that is inflated by an introduced gas to protect a head of anoccupant, the airbag (10) comprisingï a bag-shaped airbag main body section (12), wherein in the airbag main body section (12), a plurality of air chambers (23), into each of which the gas is introduced, are arranged side by side, and are connected x in a state where at least a part of 3;__an inflated portion of one of the air chambers (23) and at least a part of gpggan inflated portion of one of the other air chambers (23) overlap each other.

2. The airbag (10) according to Claim 1,wherein in the airbag main body section (12), tip sides of the one air chamber(23) and the other air chambers (23), which are adjacent to each other, are fixed and connected to each other.

3. The airbag (10) according to Claim 1 or 2, tffic) that are positioned with wherein in a state where two air chambers (23:33,one air chamber (23%) between them overlap the one air chamber (233) in the airbagmain body section (12), tip sides of the one air chamber (23šg) and the two air chambers (23:33, “ iy) are fixed and connected to each other.

4. The airbag (10) according to Claim 3,wherein the airbag main body section (12) includes a side edge joining section (25) that joins the two air chamberspš' , anda reinforcement section (28) that protects the side edge joining section(25) from a load from the one air chamber (23É;:;) to at least one of the two air chambers (23;:.:. “ s) , which accompanies inflation of the airbag main body section (12).

5. The airbag (10) according to Claim 4,wherein the side edge joining section (25) and the reinforcement section (28)each are a sewing section formed of a sewing thread, and the reinforcement section (28) eXtends along a direction intersecting the side edge joíníng section (25).