Patent Publication Number: US-2022232910-A1

Title: Wearable airbag device

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority from Japanese Patent Application No. 2021-12258 of Yanagisawa et al., filed on Jan. 28, 2021, the entire disclosure of which is incorporated herein by reference. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a wearable airbag device for protecting the hip of a wearer. 
     2. Description of Related Art 
     WO 2019/207474 A1 discloses a wearable airbag device for protecting the hip of a wearer such as an elderly person in the event of a fall or the like. This airbag device is designed to be wrapped around the pelvis of the wearer so as to inflate and deploy an airbag downward for protecting their hip when activated. 
     Since the above airbag device is configured to deploy the airbag downward from a state wrapped around the pelvis, the airbag as deployed comes to flare out and float away from the hip at the bottom. In other words, in the above airbag device, the airbag is wrapped around the pelvis which is narrower than the hip where the trochanters are located, and deployed downward therefrom to cover the hip which is thicker than the pelvis. As a consequence, the airbag as deployed comes to float away from the hip at the bottom. There is a fear that such an airbag fails to cover the hip quickly and adequately in the event of a fall or the like. 
     SUMMARY 
     An exemplary embodiment in the present disclosure relates to a wearable airbag device adapted to be wrapped around the pelvis of a wearer for protecting the hip of the wearer. The airbag device includes an airbag that is configured to be inflated with an inflation gas, and an outer cover that covers an outer circumference of the airbag and is configured to hold the airbag as inflated, the outer cover being formed of a sheet material having flexibility. The airbag includes: two protecting portions each of which is configured to cover an outer side of a targeted body part of the wearer at airbag deployment, the targeted body part being left and right trochanters of femurs; and a communicating path that is configured to provide gas communication between the two protecting portions at vicinities of upper end regions of the protecting portions. The outer cover includes: a wrap portion that is disposed in a vicinity of an upper edge of the outer cover and adapted to be wrapped around the pelvis of the wearer; and a means for suppressing each of the protecting portions from floating away from the body of the wearer at airbag deployment. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  schematically depicts a wearable airbag device in accordance with the exemplary embodiment as worn by a wearer. 
         FIG. 2  is a bottom view of the wearable airbag device of the exemplary embodiment as laid flat. 
         FIG. 3  is a sectional end view taken along line III-III of  FIG. 2 . 
         FIG. 4  is a sectional end view taken along line IV-IV of  FIG. 2 . 
         FIG. 5  is a plan view of an airbag for use in the wearable airbag device of the exemplary embodiment as laid flat. 
         FIG. 6A  is a partial enlarged plan view of a connecting portion in which an end portion of the airbag and an outer cover are connected to one another. 
         FIG. 6B  is an enlarged sectional view taken along line A-A of  FIG. 6A . 
         FIG. 7  schematically depicts the wearable airbag device as has deployed the airbag in a worn state. 
         FIG. 8  is a schematic partial horizontal sectional view of the airbag of  FIG. 5  as deployed taken along a front and rear direction in the wearable airbag device of the exemplary embodiment. More particularly,  FIG. 8  is a schematic horizontal sectional view of a left portion of the airbag. 
         FIG. 9  is a schematic vertical sectional view of the airbag of  FIG. 5  as deployed in the worn state. 
         FIG. 10  depicts a vicinity of a mounting belt in an initial stage of airbag deployment in the wearable airbag device in accordance with the exemplary embodiment by schematic sectional views. 
         FIG. 11  is a plan view of a wearable airbag device in accordance with an alternative embodiment as laid flat. 
         FIG. 12  is a sectional end view taken along line XII-XII of  FIG. 11 . 
         FIG. 13  is a schematic vertical sectional view of an airbag as deployed in a worn state, in the wearable airbag device of  FIG. 11 . 
         FIG. 14  is a plan view of a wearable airbag device in accordance with another alternative embodiment. 
         FIG. 15  is a schematic vertical sectional view of an airbag as deployed in a worn state, in the wearable airbag device of  FIG. 14 . 
         FIG. 16  is a plan view of a wearable airbag device in accordance with yet another alternative embodiment. 
         FIG. 17  is a schematic vertical sectional view of an airbag as deployed in a worn state, in the wearable airbag device of  FIG. 16 . 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings. However, the invention is not limited to the embodiments disclosed herein. All modifications within the appended claims and equivalents relative thereto are intended to be encompassed in the scope of the claims. 
     A wearable airbag device  51  in accordance with the exemplary embodiment is configured to be wrapped around the hip MW (more particularly, around the pelvis MP) of a wearer M, as can be seen in  FIG. 1 . Unless otherwise specified, up-down, front-rear, and left-right directions in the following description are intended to refer to up-down, front-rear, and left-right directions as viewed from the wearer M wearing the airbag device  51 . 
     As can be seen in  FIGS. 1 to 4 , the wearable airbag device  51  includes an airbag  10 , a gas generator  5  for feeding the airbag  10  with an inflation gas, an operation control device  1  that includes a sensor part  2  for detecting a fall of the wearer M and is configured to actuate the gas generator  5 , and an outer cover  20  that covers an outer circumference of the airbag  10 . In the wearable airbag device  51  in accordance with the exemplary embodiment, the airbag  10  is disposed inside the outer cover  20  in a developed or unfolded state, as can be seen in  FIGS. 2 to 4 . 
     The operation control device  1  includes a sensor part  2  that includes an angular velocity sensor capable of sensing angular velocities around three axes in up and down, front and rear, and left and right directions, and an acceleration sensor capable of sensing accelerations in the three-axis directions. The operation control device  1  is configured to actuate the gas generator  5  in response to a signal fed from the sensor part  2  as has sensed a falling behavior different from a normal behavior of the wearer M. More particularly, the operation control device  1  includes a determining means that is configured to determine based on various thresholds, and is configured to actuate the gas generator  5  upon sensing a fall of the wearer M based on the determination by the determining means. The operation control device  1  further includes a power source composed of a not-shown battery or the like for operation of the sensor part  2  and for emission of an actuating signal to the gas generator  5 . 
     The airbag  10  is made of a sheet material having flexibility. The airbag  10  of this specific embodiment is made of a fabric woven with polyester yarns, polyamide yarns or the like. The airbag  10  is held by the outer cover  20 , and adapted to be worn by a wearer M in that state through the use of a later-described wrap portion  24  of the outer cover  20  which is adapted to be wrapped around the pelvis MP of the wearer M. As can be seen in  FIGS. 3 to 5 , the airbag  10  includes an inner wall  10   a  that is configured to be disposed towards the wearer M (i.e. in the inner side) when worn, and an outer wall  10   b  that is substantially identical to the inner wall  10   a  in outer shape and configured to be disposed on the outer side when worn, and is formed into a bag inflatable into a substantially board shape by joining circumferential edges of the inner wall  10   a  and outer wall  10   b  together. As can be seen in  FIG. 5 , the airbag  10  of this embodiment includes two protecting portions  13  ( 13 L,  13 R) for covering left and right sides of the hip MW of the wearer M, and a communicating path  12  that provides gas communication between the two protecting portions  13  at upper ends  13   d  of the protecting portions  13 . The airbag  10  is designed to be bilaterally symmetrical in shape as laid flat. 
     The communicating path  12  is designed to be inflated into a rod shape elongated substantially along a left and right direction. The communicating path  12  is disposed inside the later-described wrap portion  24  of the outer cover  20 , and adapted to be disposed at the rear of the pelvis MP of the wearer M when worn. The width in an up and down direction of the communicating path  12  as laid flat is slightly smaller than the width in the up and down direction of a later-described central portion  25  of the wrap portion  24  of the outer cover  20  so that the communicating path  12  fills the central portion  25  at airbag deployment. That is, an upper edge region  12   b  of the communicating path  12 , which is inflatable, is configured to lap over a later-described mounting belt  35  (or belt body  36 ) disposed in the wrap portion  24  at an outer side of the mounting belt  35  when the airbag device  51  is worn, as can be seen in  FIG. 4 . 
     In this specific embodiment, the gas generator  5  is connected to the communicating path  12  for feeding the airbag  10  with an inflation gas, as can be seen in  FIG. 2 . Although not depicted in detail, the gas generator  5  is located at a vicinity of the center in the length direction of and at a vicinity of the center in the up and down direction of the communicating path  12 . The gas generator  5  contains a compressed gas in a sealed state, and is designed to discharge a cold gas into the airbag  10  when actuated and unsealed. The gas generator  5  is electrically connected to the operation control device  1  and configured to be actuated when fed with an actuating signal from the operation control device  1  as has sensed a fall of the wearer M. The protecting portions  13  ( 13 L,  13 R) are designed to extend downward and outwardly in the left and right direction from the communicating path  12 , in the airbag  10  as laid flat. As can be seen in  FIG. 5 , in the airbag  10  as laid flat, each of the protecting portions  13  ( 13 L,  13 R) of this embodiment is designed such that the upper edge  13   a  is disposed at a farther downward position than the upper edge  12   a  of the communicating path  12 , in a stepped manner with respect to the communicating path  12 , and such that the upper edge  13   a  inclines upward toward the outer end (or the front end as worn) so as to be inclined with respect to the upper edge  12   a  of the communicating path  12 . The inclination of the upper edge  13   a  of each of the protecting portions  13  is substantially in parallel to an inclination of a later-described terminal portion  26  ( 26 L/ 26 R) of the wrap portion  24  of the outer cover  20 . In order to cover the trochanter (greater trochanter) TP of femur and surroundings as a targeted body part amply at airbag deployment, each of the protecting portions  13  as laid flat has a substantially trapezoidal outer shape that narrows toward the lower end  13   b.  More particularly, each of the protecting portions  13  is formed substantially into a trapezoid which is substantially bilaterally symmetrical when having the upper edge  13   a  as the bottom side, so as to cover a side of the pelvis MP to the subtrochanteric region at airbag deployment. Each of the protecting portions  13  is configured such that the upper end portion  13   c  is disposed in a region of the terminal portion  26  ( 26 L/ 26 R) of the wrap portion  24 . More particularly, in the airbag  10  as laid flat, the upper end portion  13   c  of each of the protecting portions  13  is located at a farther downward position than the center in the up and down direction of the terminal portion  26  of the wrap portion  24 , as can be seen in  FIG. 2 . Even more particularly, each of the protecting portions  13  is configured such that the upper edge  13   a  is located at a slightly farther downward position than the mounting belt  35  (or belt body  36 ) at airbag deployment in a worn state, as can be seen in  FIG. 9 . That is, the airbag  10  of the exemplary embodiment is configured such that an inflated portion of each of the protecting portions  13  is located at such a position as not to overlap with the mounting belt  35  at airbag deployment in a worn state. 
     The airbag  10  of this embodiment includes, at each of opposite ends of the upper edge region in a flattened state (in other words, at the front upper edge of each of the protecting portions  13 L,  13 R in a worn state), an opening  15 , as can be seen in  FIG. 5 . Each of the openings  15  has a substantially circular shape, and is configured to allow two components of a later-described hook-and-loop fastener  30  as the fastening member disposed respectively in the inner surface  21   a  of the inner panel  21  and the inner surface  22   a  of the outer panel  22  to interlock with one another there through, as described later ( FIG. 6 ). That is, the opposite ends of the upper edge  10   c  of the airbag  10  (in other words, the front upper edges of the protecting portions  13 L,  13 R in a worn state) are respectively connected to opposite ends of the wrap portion  24  of the outer cover  20  (i.e. to later-described distal end portions  26   a  of the terminal portions  26 L,  26 R), through the use of the hook-and-loop fasteners  30  as the fastening member and the openings  15 . The airbag  10  as inflated is held by the outer cover  20  with the communicating path  12  inflated in such a manner as to fill a later-described central portion  25  of the wrap portion  24  and with the opposite ends of the upper edge  10   c  (i.e. the front upper edges of the protecting portions  13 L,  13 R in a worn state) coupled with the distal end portions  26   a  of the wrap portion  24  (more specifically, with the distal end portions  26  of the terminal portions  26 L,  26 R of the wrap portion  24 ). 
     The outer cover  20  is made of a flexible woven fabric having better touch than the base cloths of the airbag  10 . The outer cover  20  of this embodiment is formed of a woven fabric of polyester. The outer cover  20  includes an inner panel  21  that is disposed in the inner side (i.e. towards the wearer M) when worn, and an outer panel  22  that is substantially identical to the inner panel  21  in outer shape and disposed on the outer side when worn, and is formed into a bag by joining (or sewing) circumferential edges of the inner panel  21  and outer panel  22  together. Referring to  FIGS. 2 to 4 , the outer cover  20  includes a wrap portion  24  that is substantially band-shaped, located in a vicinity of the upper edge of the outer cover  20  and is adapted to be wrapped around a body part above the pelvis MP of the wearer M, and two covering portions  28  ( 28 L,  28 R) each of which extends downward from the wrap portion  24  for covering an outer circumference of the protecting portion  13  ( 13 U 13 R). 
     The wrap portion  24  includes a central portion  25  and two terminal portions  26  ( 26 L,  26 R) that extend from opposite ends of the central portion  25 . The central portion  25  is formed into a band extending substantially along the left and right direction. The communicating path  12  of the airbag  10  is disposed inside the central portion  25 . The central portion  25  as laid flat has a slightly greater width than that of the communicating path  12  so as to house the communicating portion  12  there inside. Each of the terminal portions  26  ( 26 L,  26 R) has a smaller width than the central portion  25 , and inclines upward toward the distal end portion  26   a  facing away from the central portion  25  so as to be inclined with respect to the central portion  25  in a flatly developed state. Each of the terminal portions  26 L,  26 R is inclined with respect to the central portion  25  substantially in parallel to the upper edge  13   a  of each of the protecting portions  13 L/ 13 R of the airbag  10 . The distal end portion  26   a  of each of the terminal portions  26 L,  26 R is designed to protrude slightly outwardly from the covering portion  28  ( 28 L/ 28 R) and to be narrower in width than the central portion  25 . The width of each of the distal end portions  26   a  in this embodiment is about a half of that of the central portion  25 . Each of the distal end portions  26   a  of the terminal portions  26 L,  26 R internally includes a hook-and-loop fastener  30  as the fastening member for fastening opposite ends of the upper edge  10   c  of the airbag  10  to the outer cover  20 , as described above. More specifically, the hook-and-loop fastener  30  includes a pair of a hook surface  30   a  and a loop surface  30   b  that are respectively disposed on the inner surface  21   a  of the inner panel  21  and the inner surface  22   a  of the outer panel  22 . The hook-and-loop fastener  30  of this embodiment is formed into a quadrangle which is slightly greater than the opening  15  formed in the airbag  10 , as can be seen in  FIGS. 6A and 6B . The hook-and-loop fastener  30  couples each of the opposite end portions of the upper edge  10   c  of the airbag  10  to the distal end portion  26   a  of the wrap portion  24  (more particularly, to the distal end portion  26   a  of the terminal portion  26 L/ 26 R of the wrap portion  24 ) of the outer cover  20 , by interlocking of the hook surface  30   a  and loop surface  30   b  through the opening  15 , as can be seen in  FIG. 6B . 
     The wrap portion  24  is provided with a mounting belt  35  that is adapted to be wrapped around the pelvis MP of the wearer M for putting the airbag device  51  on the wearer M. The mounting belt  35  is disposed on the inner panel  21  in the wrap portion  24  so as to be disposed between the inner panel  21  and the wearer M in a worn state, as can be seen in  FIG. 9 . In this specific embodiment, the mounting belt  35  is arranged substantially along the upper edge  24   a  of the wrap portion  24  substantially at the center in the up and down direction of the terminal portions  26 L,  26 R. That is, in the central portion  25 , the mounting belt  35  is disposed at a farther upward position than the center in the up and down direction of the central portion  25 . In this embodiment, the mounting belt  35  is held by a plurality of belt loops  32  that are attached to a surface of the inner panel  21  to face toward the wearer M (that is, to an outer surface  21   b  of the inner panel  21 ), in such a manner as to be movable with respect to the inner panel  21  (movable with respect to the inner panel  21  in a circumferential direction of the wearer M). Each of the belt loops  32  is formed into a band and joined to the inner panel  21  at upper and lower ends so as to be substantially orthogonal to the length direction of a later-described belt body  36  of the mounting belt  35 . The belt loops  32  receive the belt body  36  between themselves and the inner panel  21 . In this embodiment, fourteen belt loops  32  are provided. The mounting belt  35  includes a belt body  36  which is composed of a band-shaped member having flexibility and a buckle  38  which is composed of a male part  38   a  and a female part  38   b  respectively disposed in the opposite ends  36   a,    36   b  of the belt body  36 . As can be seen in  FIGS. 1 and 2 , the male part  38   a  of the buckle  38  is provided with an adjuster  38   c  with which the length of the belt body  36  is adjusted. In the wearable airbag device  51  in accordance with the exemplary embodiment, the mounting belt  35  constitutes a means for suppressing each of the protecting portions  13  ( 13 L,  13 R) from floating away from the body of the wearer M at airbag deployment (namely, float-suppressing means). 
     The covering portions  28  ( 28 L,  28 R) extend downwardly from the terminal portions  26 L,  26 R of the wrap portion  24 , respectively. Each of the covering portions  28 L,  28 R as laid flat has a substantially trapezoidal shape that is substantially similar to the protection portion  13  and greater than the protecting portion  13  so as to allow the protecting portion  13  to inflate smoothly there inside. 
     As can be seen in  FIG. 1 , the wearer M puts on the wearable airbag device S 1  by placing the wrap portion  24  of the outer cover  20  around the hip MW (or pelvis MP) and connecting the opposite ends  36   a,    36   b  of the belt body  36  of the mounting belt  35  with the use of the buckle  38 . If the sensor part  2  detects a falling behavior of the wearer M as wearing the airbag device S 1 , the operation control device  1  sends an actuating signal to the gas generator  5 , the gas generator  5  feeds an inflation gas to the airbag  10 , so that the airbag  10  is deployed as shown in  FIGS. 7 to 9 . 
     In the wearable airbag device S 1  in accordance with the exemplary embodiment, the protecting portions  13  for covering the targeted body parts (i.e. the trochanters TP) extend downward from the communicating path  12 . However, the airbag device S 1  includes the mounting belt  35  which is disposed in the outer cover  20  and serves as the float-suppressing means. The mounting belt  35  suppresses each of the protecting portions  13  from floating away from the hip MW at airbag deployment. Accordingly, each of the protecting portions  13  will be deployed in proximity to the targeted body part (i.e. the trochanter TP) and cover the outer side of the targeted body part (i.e. the trochanter TP) quickly and adequately. Moreover, since the outer cover  20  covers the outer circumference of the airbag  10 , the wearable airbag device S 1  has a good external appearance when worn. Furthermore, since the float-suppressing means is located in the outer cover  20 , not in the airbag  10 , the float-suppressing means will help control the location of the airbag  10  at deployment without affecting the protecting performance of the airbag  10 . 
     Therefore, the wearable airbag device S 1  in accordance with the exemplary embodiment is able to protect the hip W of the wearer M in a steady fashion. 
     More specifically, in the wearable airbag device S 1  in accordance with the exemplary embodiment, the outer cover  20  includes, on the inner panel  21  in the wrap portion  24 , the mounting belt  35  that is formed into a band and adapted to be wrapped around the pelvis MP of the wearer M for putting the airbag device S 1  on the wearer. 
     The mounting belt  35  constitutes the float-suppressing means. The mounting belt  35  disposed on the inner panel  21  facing the wearer M makes the outer cover  20  wrapped around the pelvis MP, and the outer panel  22  of the outer cover  20  facing outwardly allows upper end  13   d  regions of the protecting portions  13  including the communicating path  12  to protrude outwardly, without being affected by the mounting belt  35 . 
     Accordingly, although configured to be put on by wrapping the mounting belt  35  around the pelvis MP which is more constricted than the hip MW (i.e. the trochanters TP and surroundings), the wearable airbag device S 1  in accordance with the exemplary embodiment is able to deploy the protection portions  13  downward while allowing the upper end  13   d  regions of the protecting portions  13  including the communicating path  12  to each protrude slightly outwardly from a vicinity of the pelvis MP, thus suppresses lower end  13   b  regions of the protecting portions  13  from floating away from the targeted body parts, as can be seen in  FIG. 9 . As a consequence, each of the protecting portions  13  is able to cover an outer side of the targeted body part (the trochanter TP) adequately. 
     In the wearable airbag device S 1  in accordance with the exemplary embodiment, the mounting belt  35  (i.e. the belt body  36 ) is held by a plurality of belt loops  32  that are attached to the surface of the inner panel  21  to face the body of the wearer M when worn (that is, to the outer surface  21   b  of the inner panel  21 ), in such a manner as to be movable with respect to the inner panel  21  in a circumferential direction of the body of the wearer M. This configuration will allow the inner panel  21  of the outer cover  20  to move or slip with respect to the mounting belt  35  (i.e. the belt body  36 ) as wrapped around the pelvis MP in a circumferential direction of the pelvis MP, and will also allow the inner panel  21  to move in such a manner as to be separated outwardly from the mounting belt  35  (belt body  36 ) at flexing of the belt loops  32 . To describe more specifically referring to  FIG. 10 , in an initial stage of airbag deployment, the belt loops  32  will allow the inner panel  21  to be separated from the belt body  36  temporarily in such a manner as to be pulled outwardly so that a gap is formed between the belt body  36  and the inner panel  21  as the airbag  10  is inflated. Therefore, the upper end  13   d  regions of the protecting portions  13  including the communicating path  12  will be allowed to protrude outwardly temporarily further smoothly. If such advantageous effects do not have to be considered, the mounting belt may be connected or joined directly to the inner panel without using belt loops. Although the mounting belt  35  in this embodiment is disposed over an entire length of the wrap portion  24 , in one or more embodiments, the mounting belt may be disposed only at opposite ends of the wrap portion so as to extend from the opposite ends. 
     A wearable airbag device S 2  in accordance with an alternative embodiment is now described referring to  FIGS. 11 and 12 . The wearable airbag device S 2  includes an airbag  40 , a gas generator  5  for feeding the airbag  40  with an inflation gas, an operation control device  1  that includes a sensor part  2  for detecting a fall of the wearer M and is configured to actuate the gas generator  5 , and an outer cover  45  that covers an outer circumference of the airbag  40 . Also in the wearable airbag device S 2 , the airbag  40  is disposed inside the outer cover  45  in a developed or unfolded state, as can be seen in  FIGS. 11 and 12 . The operation control device  1  and the gas generator  5  have the same configurations as those of the airbag device S 1 , respectively, and therefore, detailed description for those will be omitted. 
     The airbag  40  is held by the outer cover  45 , and adapted to be worn by a wearer M in that state through the use of a later-described wrap portion  49  of the outer cover  45  which is adapted to be wrapped around the pelvis MP of the wearer M, as can be seen in  FIG. 13 . Similarly to the airbag  10  in the foregoing embodiment, the airbag  40  includes an inner wall  40   a  that is configured to be disposed towards the wearer M (i.e. in the inner side) when worn, and an outer wall  40   b  that is substantially identical to the inner wall  40   a  in outer shape and configured to be disposed on the outer side when worn, and is formed into a bag inflatable into a substantially board shape by sewing (joining) circumferential edges of the inner wall  40   a  and outer wall  40   b  together. The airbag  40  includes two protecting portions  43  ( 43 L,  43 R) for covering left and right sides of the hip MW of the wearer M, and a communicating path  42  that provides gas communication between the two protecting portions  43  at upper ends  43   a  of the protecting portions  43 . Each of the protecting portions  43  is not inclined with respect to the communicating portion  42 , but is formed such that the upper edge continues from the upper edge of the communicating path  42 . The airbag  40  has the same configuration as that of the airbag  10  of the wearable airbag device S 1  except in outer shape. 
     Similarly to the outer cover  20  of the airbag device S 1 , the outer cover  45  is made of a flexible woven fabric having better touch than the base cloths of the airbag  40 . The outer cover  45  includes an inner panel  46  that is disposed in the inner side (i.e. towards the wearer M) when worn, and an outer panel  47  that is substantially identical to the inner panel  46  in outer shape and disposed on the outer side when worn, and is formed into a bag by joining (or sewing) circumferential edges of the inner panel  46  and outer panel  47  together. As can be seen in  FIG. 11 , the outer cover  45  includes a wrap portion  49  that is substantially band-shaped, located in a vicinity of the upper edge of the outer cover  45  and is adapted to be wrapped around a body part above the pelvis MP of the wearer M, and two covering portions  52  ( 52 L,  52 R) each of which extends downward from the wrap portion  49  for covering an outer circumference of the protecting portion  43  ( 43 L/ 43 R). The wrap portion  49  is provided, in the opposite ends  49   a,    49   b,  with a hook-and-loop faster  50  as a fastening means. The hook-and-loop fastener  50  includes a pair of a hook surface  50   a  and a loop surface  50   b  that are respectively disposed on the opposite ends  49   a,    49   b  of the wrap portion  49  so as to fasten the opposite ends  49   a,    49   b  of the wrap portion  49  together. Each of the covering portions  52 L,  52 R as laid flat has such an outer shape that is substantially similar to the protection portion  43  and greater than the protecting portion  43  so as to allow the protecting portion  43  to inflate smoothly there inside. 
     The outer cover  45  of this embodiment includes, in a part of the outer panel  47 , a low-elongation region  55  that is provided with a material having lower elongation than the inner panel  46  and remaining regions of the outer panel  47 . The low-elongation region  55  of this specific embodiment is formed by forming, on a surface of the outer panel  47 , a synthetic-resin layer that has lower elongation than the woven fabric forming the outer panel  47  and inner panel  46  and also has some degree of flexibility. By way of example, the synthetic-resin layer may be composed of a coating layer of urethane, nylon or the like. The low-elongation region  55  is able to prevent the protecting portion  43  as is inflating from protruding toward a floating direction and help deploy the protecting portion  43  downward in such a manner as to push down the protecting portion  43 . In various embodiments, the low-elongation region  55  may be given a different color from the surrounding area in the outer panel  47 , a mark, or an ornamentation like a letter(s) for a better appearance. In this embodiment, as can be seen in  FIGS. 11 and 12 , two low-elongation regions  55  are disposed in a vicinity of the upper end  47   a  of the outer panel  47 , more particularly, in the regions each ranging from the wrap portion  49  to the upper end  52   a  region of the covering portion  52 . In the wearable airbag device S 2 , each of the low-elongation regions  55  in the outer panel  47  constitutes the means for suppressing each of the protecting portions  43  from floating away from the body of the wearer M at airbag deployment (i.e. the float-suppressing means). 
     The above configuration will make at least a part of the outer panel  47  of the outer cover  45  (i.e. the low-elongation region  55 ) less prone to elongate than the inner panel  46 , i.e. make the inner panel  46  more prone to elongate relatively. That is, the above configuration will help deploy the protecting portions  43  of the airbag  40  toward the inner panel  46 , i.e. toward the wearer M, in such a manner as to push the protecting portions  43  downwardly not toward a floating direction, due to the presence of the low-elongation regions  55  formed in the outer panel  47  of the outer cover  45 . Therefore, each of the protecting portions  43  will be suppressed from floating away from the targeted body part (the trochanter TP) at the lower end  43   b  at deployment, thus will be able to cover the outer side of the targeted body part (the trochanter TP) adequately, as can be seen in  FIG. 13 . To describe more specifically, in the wearable airbag device S 2 , each of the low-elongation regions  55  is formed in the region ranging from the wrap portion  49  to the upper end  52   a  region of the covering portion  52 . In other words, the low-elongation region  55  is formed in the region for covering an outer side of the upper end  43   a  region of the protecting portion  43  of the airbag  40 . This configuration will suppress the upper end  43   a  region of each of the protecting portions  43  from protruding outwardly at airbag deployment and help deploy the protecting portions  43  downwardly smoothly in such a manner as to push down the protecting portions  43 . As a consequence, each of the protecting portions  43  will be suppressed from floating away from the targeted body part at the lower end  43   b  region, as can be seen in  FIG. 13 , and will be able to cover the outer side of the targeted body part (the trochanter TP) adequately. The location of the low-elongation region should not be limited to the disclosed embodiments, but may be determined arbitrarily provided that it is located in a region of the outer panel for covering the protecting portion. In various embodiments, the low-elongation region may be formed by impregnating the outer panel with urethane resin or nylon resin. Further alternatively, the outer panel itself may be composed of a material having lower elongation than that of the inner panel so the whole outer panel serves as the low-elongation region. By way of example, the outer panel may be composed of cotton, linen or the like different from the material of the inner panel, a base member having a different weave structure (high-density plain weave material, by way of example) from that of the inner panel, or a two-ply base member. 
     The outer cover may be configured like an outer cover  45 A depicted in  FIGS. 14 and 15 . Instead of including a low-elongation region in the outer panel, the outer cover  45 A includes a weight  57  in a vicinity of the lower end  52   b  of the covering portion  52 A (i.e. in a vicinity of the lower end of the outer cover). As can be seen in  FIGS. 14 and 15 , the weight  57  is formed into a plate arranged over an entire area in a width direction of the covering portion  52 A in the outer panel  47 A, in the vicinity of the lower end  52   b  of the covering portion  52 A. The weight  57  is connected to the outer panel  47 A by a not-shown predetermined portion(s). In this outer cover  45 A, the weight  57  constitutes the means for suppressing the protecting portion  43  from floating away from the body of the wearer M at airbag deployment. 
     At airbag deployment, the weight  57  disposed in a vicinity of the lower end of the outer cover  45 A (in a vicinity of the lower end  52   b  of the covering portion  52 A) will act in such a manner as to pull the protecting portion  43  downwardly, and suppress the protecting portion  43  from floating away from the targeted body part (the trochanter TP) at the lower end  43   b  region, so that the protecting portion  43  will cover an outer side of the targeted body part (the trochanter TP) adequately, as can be seen in  FIG. 15 . Although the weight  57  is disposed in the outer panel  47 A in the depicted embodiment, it may be located in the inner panel. 
     Further alternatively, the outer cover may be configured like an outer cover  45 B depicted in  FIGS. 16 and 17 . The outer cover  45 B includes, in a vicinity of the lower end  52   b  of the covering portion  52 B (i.e. in a vicinity of the lower end of the outer cover), a wrap band  59  that is adapted to be wrapped around the femoral region MT of the wearer M. The wrap band  59  is adapted to be wrapped around the femoral region MT when the wearer M puts on the wearable airbag device by wrapping the wrap portion of the outer cover  45 B around the pelvis. The wrap band  59  of this specific embodiment internally includes a plate spring so as to roll up around the femoral region MT when applied to the femoral region MT and keep rolled. More specifically, the wrap band  59  extends from an outer edge in a left and right direction of the outer cover  45 B as laid flat in a vicinity of the lower end  52   b  of the covering portion  52 B. Although not depicted in detail, the length of the wrap band  59  is longer than a circumferential length of the femoral region MT. In the outer cover  45 B, the wrap band  59  constitutes the means for suppressing the protecting portion  43  from floating away from the body of the wearer M at airbag deployment. 
     With the outer cover  45 B configured as described above, the wrap band  59  as wrapped around the femoral region MT will prevent the lower end  45   a  region of the outer cover  45 B (i.e. the lower end  52   b  of the covering portion  52 B) from being separated from the femoral region MT at airbag deployment. Accordingly, the protecting portion  43  will be suppressed from floating away from the targeted body part (the trochanter TP) at the lower end  43   b  region at airbag deployment, and will be able to cover the outer side of the targeted body part (the trochanter TP) adequately, as can be seen in  FIG. 17 . Although the wrap band  59  of the above embodiment internally includes a plate spring to wrap around the femoral region when applied to the femoral region, the wrap band does not necessarily have to include a plate spring. In one or more embodiments, the wrap band may include a means for fastening its opposite ends such as a hook-and-loop faster or one or more snap fasteners. 
     With the wearable airbag devices S 1  and S 2  in the foregoing embodiments, the two protecting portions  13 ,  43  of the airbags  10 ,  40  are able to protect vicinities of bases of the femurs TB (i.e. the trochanters TP of femurs) of the wearer M in a steady fashion. That is, the wearable airbag devices S 1  and S 2  in accordance with the foregoing embodiments will help prevent fractures of the femur TB that may take a long time to treat, thus will be suitable for use by elderly people. 
     In the wearable airbag devices S 1  and S 2  in accordance with the foregoing embodiments, the airbag  10 ,  40  is stored in the outer cover  20 ,  45 ,  45 A,  45 B in a flatly developed state. However, in a type of the airbag device in which a mounting belt serves as the float-suppressing means, the airbag and the outer cover may be configured to be wrapped around the pelvis in a folded configuration provided that the outer cover is able to hold and cover an outer circumference of the airbag as deployed. 
     The exemplary embodiment of the present disclosure relates to a wearable airbag device adapted to be wrapped around the pelvis of a wearer for protecting the hip of the wearer. The airbag device includes an airbag that is configured to be inflated with an inflation gas, and an outer cover that covers an outer circumference of the airbag and is configured to hold the airbag as inflated, the outer cover being formed of a sheet material having flexibility. The airbag includes: two protecting portions each of which is configured to cover an outer side of a targeted body part of the wearer at airbag deployment, the targeted body part being left and right trochanters of femurs; and a communicating path that is configured to provide gas communication between the two protecting portions at vicinities of upper end regions of the protecting portions. The outer cover includes: a wrap portion that is disposed in a vicinity of an upper edge of the outer cover and adapted to be wrapped around the pelvis of the wearer; and a means for suppressing each of the protecting portions from floating away from the body of the wearer at airbag deployment. 
     In the wearable airbag device in accordance with the exemplary embodiment, the protecting portions for covering the targeted body parts (i.e. the trochanters) extend downward from the communicating path, in the airbag. However, the means for suppressing suppresses each of the protecting portions from floating away from the hip at airbag deployment. Accordingly, each of the protecting portions will be deployed in proximity to the targeted body part (i.e. the trochanter) and cover the outer side of the targeted body part (i.e. the trochanter) quickly and adequately. Moreover, since the outer cover covers the outer circumference of the airbag, the wearable airbag device has a good external appearance when worn. Furthermore, since the means for suppressing is located in the outer cover, not in the airbag, the means for suppressing will help control the location of the airbag at deployment without affecting the protecting performance of the airbag. 
     Therefore, the wearable airbag device in accordance with the exemplary embodiment is able to protect the hip of the wearer in a steady fashion. 
     In one or more embodiments, the outer cover may include: an inner panel that is configured to be disposed between the airbag and the body of the wearer when worn; an outer panel that is configured to face away from the wearer when worn; and a mounting belt that is adapted to be wrapped around the pelvis of the wearer for putting the airbag device on the wearer, the mounting belt having a band shape and being disposed on the inner panel in the wrap portion, the mounting belt constituting the means for suppressing. 
     With the above configuration, the mounting belt disposed on the inner panel facing the wearer makes the outer cover wrapped around the pelvis, and the outer panel of the outer cover facing outwardly allows upper end regions of the protecting portions including the communicating path to protrude outwardly, without being affected by the mounting belt. Accordingly, although configured to be put on by wrapping the mounting belt around the pelvis which is more constricted than the hip (i.e. the trochanters and surroundings), the wearable airbag device in accordance with the exemplary embodiment is able to deploy the protection portions downward while allowing the upper end regions of the protecting portions including the communicating path to each protrude slightly outwardly from a vicinity of the pelvis, thus suppresses lower end regions of the protecting portions from floating away from the targeted body parts. As a consequence, each of the protecting portions is able to cover an outer side of the targeted body part (the trochanter) adequately. 
     In one or more embodiments, the wearable airbag device may further include a plurality of belt loops that are attached to a surface of the inner panel of the outer cover to face the body of the wearer when worn, the plurality of belt loops holding the mounting belt in such a manner that the mounting belt is movable with respect to the inner panel in a circumferential direction of the body of the wearer. 
     The above configuration will allow the inner panel of the outer cover to move or slip with respect to the mounting belt as wrapped around the pelvis in a circumferential direction of the pelvis, and will also allow the inner panel to move in such a manner as to be separated outwardly from the mounting belt at flexing of the belt loops. Therefore, the upper end regions of the protecting portions including the communicating path will be allowed to protrude outwardly temporarily further smoothly. 
     In one or more embodiments, the outer cover may include: an inner panel that is configured to be disposed between the airbag and the body of the wearer when worn; an outer panel that is configured to face away from the wearer when worn; and a low-elongation region that is disposed at least in a part of the outer panel and has lower elongation than the inner panel, the low-elongation region being configured to prevent each of the protecting portions as is inflating from protruding toward a direction drawing away from the body of the wearer and help deploy each of the protecting portions downward in such a manner as to push down the protecting portion, the low-elongation region constituting the means for suppressing. 
     The above configuration will make at least a part of the outer panel of the outer cover (i.e. the low-elongation region) less prone to elongate than the inner panel, i.e. make the inner panel more prone to elongate relatively. That is, the above configuration will help deploy the protecting portions of the airbag toward the inner panel, i.e. toward the wearer, in such a manner as to push the protecting portions downwardly not toward a floating direction, due to the presence of the low-elongation region formed in the outer panel of the outer cover. Therefore, each of the protecting portions will be suppressed from floating away from the targeted body part (the trochanter) at the lower end at deployment, thus will be able to cover the outer side of the targeted body part (the trochanter) adequately. 
     In one or more embodiments, the outer cover may include, in a vicinity of the lower end, at least one weight that serves as the means for suppressing. At airbag deployment, the weight will act in such a manner as to pull each of the protecting portions downwardly, and suppress each of the protecting portions from floating away from the targeted body part (the trochanter) at the lower end region, so that each of the protecting portion will cover an outer side of the targeted body part (the trochanter) adequately. 
     In one or more embodiments, the outer cover may include, in a vicinity of the lower end, at least one wrap band that is adapted to be wrapped around the femoral region of the wearer and serves as the means for suppressing. The wrap band as wrapped around the femoral region will prevent the lower end region of the outer cover from being separated from the femoral region at airbag deployment. Accordingly, each of the protecting portions will be suppressed from floating away from the targeted body part (the trochanter) at the lower end region at airbag deployment, and will be able to cover the outer side of the targeted body part (the trochanter) adequately.