Patent Publication Number: US-2023137642-A1

Title: Body Supporting Device and Fan Unit Bag

Description:
TECHNICAL FIELD 
     The present invention relates to a body supporting device and a fan unit bag to which a fan unit is attached in a removable manner. 
     BACKGROUND ART 
     In a stroller serving as a body supporting device, a seat that is a body support where an occupant such as an infant rides on is close to a road surface. Thus, the seat becomes hot during the summer or the like. For this reason, a user may set a small fan unit or the like on the seat of the stroller. Such a fan unit, however, is seldom used in seasons other than summer. A fan unit may be attached to clothing (refer to Patent Literature  1 ). 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: Japanese Patent No. 6568611 
     SUMMARY OF INVENTION 
     Technical Problem 
     A fan unit has to be stably positioned when attached to the stroller for use so that it will not fall off or change the direction it faces with the person operating the stroller not being aware of such a situation. Nevertheless, it is desirable that the fan unit be easily removable from the stroller. 
     A fan unit may be used with a body supporting device such as a chair, a sofa, or a wheelchair. Such a fan unit also has to be stably positioned when attached so that it will not fall off or change the direction it faces with the user not being aware of such a situation, while also being easily removable. 
     It is an objective of the present invention to provide a body supporting device and a fan unit bag that allow for stable attachment of a fan unit, while allowing the fan unit to be easily attached to and removed from a body support. 
     Solution to Problem 
     To achieve the above objective, a body supporting device includes a body support. The body supporting device includes a fan unit bag attached in a removable manner to a rear side of the body support. The fan unit bag includes a fan unit that draws air from the body support, a fan base that supports the fan unit so that the fan unit faces the body support, the fan base being a sheet having low air permeability, and a fastener that attaches the fan base in a removable manner to the body support. The fastener is arranged to surround the fan unit. 
     The above structure drives the fan unit, which is fixed to the fan base by the fastener that surrounds the fan unit, to discharge moisture and hot air from the body support. The fan unit is stably attached to the body supporting device by the fan unit bag. The fastener allows the fan unit bag to be easily attached to and detached from the body support. 
     In the body supporting device, the body support includes, for example, a backrest. The backrest may include an inner sheet located closer to a body than the fan unit bag. In this case, preferably, the inner sheet includes a cushion, which supports a back or a head, and, a cover, which covers the cushion. 
     The above structure arranges the inner sheet including the cushion in the backrest. This improves the riding comfort. The fan unit bag discharges moisture and hot air from the cushion. 
     In the body supporting device, the cover includes a sheet that is located at a side closer to the body and formed by an air permeable sheet and a sheet located at a side closer to the fan unit bag and formed by a low air permeability sheet. The low air permeability sheet includes a region defining an air permeable portion where air permeability is higher than the low air permeability sheet. Preferably, when the fan unit bag is attached to the backrest, the fan unit is arranged facing the air permeable portion. 
     The above structure can efficiently discharge air from the entire cushion through the air permeable portion by driving the fan unit even if the backrest includes the inner sheet. 
     In the body supporting device, the backrest may be located toward a rear side of the body supporting device from a seat and include a shoulder belt. Preferably, in a state where the fan unit bag is attached to the backrest, the fan unit is located between a lower portion of the backrest and an extracted position of the shoulder belt. 
     Regardless of size such as height of the occupant, at least part of the back of the occupant will rest on a position between the lower portion of the backrest and the extracted position of the shoulder belt. The above structure arranges the fan unit at such a position and efficiently discharges moisture and hot air from the cushion. 
     In the body supporting device, the backrest may be located toward a rear side of the body supporting device from a seat and include a shoulder belt. Preferably, the air permeable portion is located between a lower portion of the backrest and an extracted position of the shoulder belt. The above structure arranges the air permeable portion between the lower portion of the backrest and the extracted position of the shoulder belt to efficiently discharge moisture and hot air from the cushion. 
     In the body supporting device, the fan base includes a base portion and a fan attaching portion to where the fan unit is attached. In this case, preferably, the fan attaching portion is folded toward the base portion, with the fan unit attached thereto, and fixed to the base portion. The above structure allows the fan unit to be easily attached to the fan base so that the fan unit is positioned at a predetermined position. 
     In the body supporting device, a peripheral part of the fan attaching portion, excluding a bent part bordering the base portion, may include a fan fastener that fastens the fan attaching portion to the base portion. The above structure makes the surrounding of the fan attaching portion more airtight and allows air to be discharged further efficiently. 
     In the body supporting device, preferably, the fan base includes the fastener at a peripheral part of a surface facing the body support and at an intermediate portion extending between two vertical edges on the surface facing the body support. The above structure allows the fan unit bag to be further firmly attached to the backrest and makes the surrounding of the fan unit more airtight. 
     In the body supporting device, it is preferable that the body support includes a base sheet attached to a frame for forming the body support, the base sheet is an air permeable sheet, and the fan unit bag is attached so that the fan base is adjacent to the base sheet. The above structure forms the fan base with a low air permeability sheet. Thus, even if the fan unit bag is attached to an air permeable inner sheet of the stroller, the fan unit can efficiently discharge moisture and hot air can from the backrest. 
     In the body supporting device, the backrest may include a base sheet attached to a frame of the body support. In this case, the inner sheet is arranged at a side of the base sheet that is closer to the body, and the fan unit bag is coupled to the inner sheet and the base sheet. The above structure couples the fan unit bag to the inner sheet and the base sheet. Thus, the fan unit bag will resist undesirable separation from the backrest. 
     In the body supporting device, the fan unit may include a flat portion and a protruding portion protruding opposite the flat portion. In this case, the fan unit is arranged so that the flat portion faces the body support when the fan unit bag is attached to the body support. The above structure softens contact with the body supported by the body support of the fan unit and maintains the sitting comfort, the sleeping comfort, the riding comfort, and the like. 
     A fan unit bag that achieves the above objective is attached to a rear side of a body support of a body supporting device. The fan unit bag includes a fan unit that draws air from the body support, a fan base that supports the fan unit so that the fan unit faces the body support, in which the fan base is a low air permeability sheet, and a fastener that attaches the fan base in a removable manner to the body support. The fastener is arranged to surround the fan unit. 
     The above structure allows the fan unit to be easily attached to and detached from the body support in a stable state. Further, the fan base is a low air permeability sheet. Thus, moisture and hot air can be efficiently discharged from the backrest even if the fan unit bag is attached. 
     Advantageous Effects of Invention 
     According to the present invention, the fan unit can be easily attached to and detached from the body support in a state stably attached to the body support. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a front perspective view of a stroller. 
         FIG.  2    is a perspective view illustrating a main part of a fan unit bag in an attached state. 
         FIG.  3    is a perspective view taken from a front side of the fan unit bag showing a fan unit attached to a fan attaching portion. 
         FIG.  4    is a perspective view taken from a rear side of the fan unit bag showing the fan unit when being attached to the fan attaching portion. 
         FIG.  5    is a rear view taken from the rear side of the fan unit bag showing the fan unit attached to the fan attaching portion. 
         FIG.  6    is a rear view of the fan unit bag showing a state in which the fan attaching portion is folded on a base. 
         FIG.  7    is a perspective view showing the main part of the fan unit bag in a state attached to a backrest. 
         FIG.  8    is a perspective view showing the main part of the fan unit bag in a state coupled to an inner sheet and a base sheet. 
         FIG.  9    is a schematic cross-sectional view illustrating a cooling operation of the fan unit bag. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     A body supporting device and a fan unit bag in accordance with the present invention will now be described with reference to  FIGS.  1  to  9   . 
       FIG.  1    shows a single-seat foldable stroller  1  that is an example of the body supporting device and used to carry an infant or the like. The stroller  1  carries an occupant such as an infant in a lying posture or a seated posture.  FIG.  1    illustrates a state in which a cushion such as a base sheet and a hood are attached to a frame.  FIG.  1    illustrates the stroller  1  in a state in which a handle  19  is located at the rear of the stroller  1  so that the stroller  1  can be pushed from behind. In the following description, the state in which the stroller  1  is pushed from behind is used as a frame of reference. The traveling direction is defined as the front direction, the direction opposite the traveling direction is defined as the rear (back) direction, the lateral direction with respect to the traveling direction is defined as the left-right (widthwise) directions, and the vertical direction with respect to the traveling direction is defined as the up-down directions. 
     The stroller  1  illustrated in  FIG.  1    includes a fan unit bag  2 , which is shown in  FIG.  2   , for attaching a fan unit  41  to the stroller  1 . The fan unit bag  2  is attached in a removable manner to the stroller  1 . 
     Stroller 
     As illustrated in  FIG.  1   , the stroller  1  includes a two front leg frames  11 , two rear leg frames  12 , and a seating unit  13  that carries an occupant such as an infant in a lying posture or a seated posture. The seating unit  13  is a body support that supports the body of the occupant in various postures. Each of the front leg frames  11  has a slightly curved shape and includes a lower end provided with a caster, or front wheel  11   a.  Each of the rear leg frames  12  has a linear shape and includes a lower end provided with a caster, or rear wheel  12   a.  A front stay  14  extends between the two front leg frames  11  in the left-right direction. A step  16  is arranged on the front stay  14  and used as a rest for the feet of the seated occupant. The space below the seating unit  13  defines a storage portion  15  where small items can be stored on a net extending between the front leg frame  11  and the rear leg frame  12 . 
     The upper ends of the two front leg frames  11  are pivotally supported by armrests  17 . The upper ends of the two rear leg frames  12  are also pivotally supported by the armrests  17 . The seating unit  13 , which is formed between the two front leg frames  11  and the two rear leg frames  12 , includes a seat  13   a  and a backrest  13   b.    
     The seat  13   a  is located at a height between the armrest  17  and the front and rear wheels  11   a  and  12   a.  Specifically, the seat  13   a  includes frames, extending in the front-rear direction between the front leg frames  11  and the rear leg frames  12 , and a base sheet  31 , extending between the side frames. The backrest  13   b  includes frames coupled to the rear leg frames  12 , the side frames, and the like. The base sheet  31  extends between the frames of the backrest  13   b.  That is, the base sheet  31  is a sheet arranged on the seat  13   a  and the backrest  13   b.  An inner sheet  32  is arranged on the base sheet  31 . 
     Shoulder belts  21  having proximal ends fixed to the base sheet  31  extend from the backrest  13   b.  The inner sheet  32  includes slits  22  from which the shoulder belts  21  can be extracted at different heights in the up-down direction of the backrest  13   b.  The distal end of each shoulder belt  21  is coupled to a buckle  25  together with a waist belt  23  and a crotch belt  24  that extend from the seat  13   a.  The buckle  25  is provided at the distal end of the crotch belt  24 . 
     A front guard  18  is attached in a removable manner to distal ends of the armrests  17 . The handle  19  for pushing and moving the stroller  1  is located outward from the armrests  17  in the widthwise direction. The handle  19  has the shape of a reversed U as a whole. Furthermore, a hood  26  supported by the handle  19  is arranged on the upper part of the seating unit  13 . 
     The side frames, the front leg frames  11 , the rear leg frames  12 , the armrests  17 , the frames of the backrest  13   b,  and the handle  19  are moved in cooperation to fold and unfold the stroller  1 .  FIG.  1    illustrates the unfolded state. 
     As described above, the seating unit  13  includes the base sheet  31  and the inner sheet  32 . The base sheet  31  extends over the seat  13   a  and above the seat  13   a  between the frames of the backrest  13   b.  The base sheet  31  is a flexible sheet having superior flexibility. The base sheet  31  is an air permeable sheet such as a mesh sheet. 
     The inner sheet  32  includes a seat portion  33  and a backrest portion  34 . The seat portion  33  includes a cushion and a cover that accommodates the cushion. In one example, the cushion is a high-repulsion cushion having air permeability and formed by entangled, elastic synthetic resin fibers. Such a cushion is accommodated in a cover formed by sewing a bag from a mesh sheet. 
     The backrest portion  34  also includes a cushion  35  and a cover  36  that covers the cushion  35  (see  FIG.  9   ). The cushion  35  is separate from the cushion of the seat portion  33 . The cover  36  may be continuous with the cover of the seat portion  33  or be separate and stitched to form a cover continuous with the seat portion  33 . In this case, the seat portion  33  and the backrest portion  34  are defined by stitching the front and back sheets. 
     In one example, the cushion  35  of the backrest portion  34  may also by a high-repulsion cushion. A highly-repulsion cushion is more repulsive than a normal cushion formed of a normal non-woven fabric and thus has many voids resulting in high air permeability. The cover  36  includes a surface at the side that contacts the occupant formed by an air permeable sheet  36   a,  such as a mesh sheet, and a surface at the side of the base sheet  31  formed by a low air permeability sheet  36   b  having lower air permeability than the air permeable sheet  36   a.  One example of the low air permeability sheet is a nylon sheet. The low air permeability sheet  36   b  includes an air permeable portion  37  located at a position lower than where the shoulder belts  21  are extracted from, namely, the lowermost slits  22  and higher than the lower part of the backrest portion  34 . That is, the air permeable portion  37  is located between the lowermost slits  22  and the lower part of the backrest portion  34  that is proximate to the seat portion  33 . The air permeable portion  37  is formed by, for example, a mesh sheet or a net. 
     The seat  13   a  of the seating unit  13  is formed by the seat portion  33  of the inner sheet  32  and the portion of the base sheet  31  extending between the side frames. The backrest  13   b  is formed by the backrest portion  34  of the inner sheet  32  and the portion of the base sheet  31  extending between the frames of the backrest  13   b.  The backrest portion  34  supports not only the back of the occupant but also the head of the occupant. 
     Fan Unit Bag 
     As illustrated in  FIG.  2   , the fan unit bag  2  is attached in a removable manner to the backrest  13   b  and located at the rear side of the backrest  13   b.  The fan unit bag  2  includes the fan unit  41  and a fan base  42  that is formed by a sheet and supports the fan unit  41 . The fan unit bag  2  further includes a battery pack  43 , which supplies power to the fan unit  41 , and an output cable  44 , which electrically connects the fan unit  41  and the battery pack  43 . The fan unit bag  2  includes an outer surface  40   a  facing the rear of the stroller  1  and an inner surface  40   b  facing the base sheet  31 . 
     In this example, there are two fan units  41  arranged side by side at the lower side of the fan base  42 . Each fan unit  41  includes a motor and a fan that are arranged in a case. Each fan unit  41  has one surface forming a flat portion  41   a  and an opposite surface forming a protruding portion  41   b  (see  FIG.  3   ). The fan unit  41  is actuated to draw air from the flat portion  41   a  and discharge air from the protruding portion  41   b.    
     The battery pack  43  has a rectangular parallelepiped shape. The battery pack  43  includes a rechargeable battery pack, such as, for example, a lithium-ion battery or a nickel-metal hydride battery, and an operating unit for the fan units  41 . The operating unit includes a power button for switching power on and off for the fan units  41 , a mode selection button for setting the air current generated by the fan, a battery level display section, and a mode display section indicating the present mode. The fan units  41  and the battery pack  43  are electrically connected by the output cable  44 . The battery pack  43  includes a controller that executes controls, such as drive control of the fan unit  41  and charge control of the rechargeable battery pack. The controller executes drive control on the fan unit  41  in accordance with an input from the operating unit. The fan unit  41  is controlled by the controller and driven in modes such as a strong mode, a moderate mode, a weak mode, and a turbo mode. 
     As illustrated in  FIG.  3   , the fan base  42  includes a base portion  46  and a fan attaching portion  47 . The base portion  46  and the fan attaching portion  47  are rectangular sheets and formed by flexible low air permeability sheets that close the mesh of the base sheet  31 . The low air permeability sheet may be a sheet of vinyl chloride. In this example, a nylon sheet is used. Approximately three-quarters of the fan base  42  from the top in the longitudinal direction is the base portion  46  and the remaining approximately one-quarter is the fan attaching portion  47 . 
     The base portion  46  is a rectangular region and has substantially the same size as the backrest  13   b.  One surface of the base portion  46  defines a first surface  46   a  forming the outer surface  40   a  of the fan unit bag  2 . The first surface  46   a  includes a pocket  48  that accommodates the battery pack  43  and is located at a longitudinally middle position toward one side in the widthwise direction. The pocket  48  includes a flap  48   a  that opens and closes an insertion opening. The flap  48   a  is formed by a transparent waterproof sheet. The flap  48   a  is closed when the battery pack  43  is accommodated in the pocket  48  to protect the battery pack  43  from rainwater. The battery pack  43  is inserted into the pocket  48  so that the operating unit faces the upper side in order to allow for visual recognition of the operating unit through the flap  48   a  even when the insertion opening is closed and also allow the operating unit to be operated when the insertion opening is open. 
     A storage cover  49  is arranged on the first surface  46   a  of the base portion  46  between the fan attaching portion  47  and the pocket  48 . The storage cover  49  has substantially the same size as the fan attaching portion  47 . The storage cover  49  may be a net having superior air permeability. Each fan unit  41 , in particular, the protruding portion  41   b  at the discharge side, is arranged at the inner side of the storage cover  49 . The storage cover  49 , which is formed by a net, does not interfere with the discharge of air. The storage cover  49  is stitched to the first surface  46   a.  An upper corner of the storage cover  49  located below a cord cover  45  is not stitched to the first surface  46   a.  The part where the storage cover  49  is not stitched serves as a cable opening  49   a  through which an output cable  44  from the fan units  41  can be extended. 
     The fan attaching portion  47  is located at the lower side of the storage cover  49 . In the fan attaching portion  47 , the surface continuous with the first surface  46   a  of the base portion  46  faces the base sheet  31  when the fan unit bag  2  is attached to the backrest  13   b.  The fan attaching portion  47  is a rectangular region having substantially the same size as the storage cover  49 . The fan attaching portion  47  borders the storage cover  49  at a bent part  50  formed when the fan attaching portion  47  is folded to lap the storage cover  49 . 
     The fan attaching portion  47  includes attachment holes  51  that receive the two fan units  41 . The attachment holes  51  are circular holes and arranged side by side in the widthwise direction. In  FIG.  3   , the fan units  41  are inserted into the attachment holes  51  from the protruding portions  41   b.    
     The upper corners include loops  58 . Coupling belts  59  arranged on the upper corners of the inner sheet  32  of the backrest portion  34  are passed through the loops  58 . The upper corners of the first surface  46   a  include studs  54  to which eyelets on the coupling belts  59  are fastened. Base coupling belts  60  passed through loops  60   a  of the base sheet  31  are arranged on the two sides of the base portion  46 . Hook-and-loop fasteners  55  for the hood are arranged near the studs  54  and coupled to hook-and-loop fasteners of the hood. 
       FIG.  4    shows the inner surface  40   b  of the fan unit bag  2 . The protruding portion  41   b  of the fan unit  41  protrudes from the other surface of the base portion  46 , namely, the second surface  46   b.  Ring members  52  are attached to the second surface  46   b.  The ring members  52  are fixed to the rims of the protruding portion  41   b  with the edges defining the attachment holes  51  held in between. Thus, each fan unit  41  is arranged with the flat portion  41   a  facing the first surface  46   a  of the base portion  46  (see  FIG.  3   ), and the protruding portion  41   b  facing the second surface  46   b  (see  FIG.  4   ). 
     As illustrated in  FIG.  5   , jacks, to which terminals of the output cable  44  can be connected, are arranged on the upper sides of the fan units  41  received in the attachment holes  51 . The output cable  44  is arranged in the storage cover  49 , with the terminals connected to the jacks, and connected to a connector  44   a  that extends out of the cable opening  49   a  and is further connected to the battery pack  43 . The first surface  46   a  includes a cord cover  45  that holds the output cable  44  above the cable opening  49   a.    
     With the fan units  41  attached to the fan attaching portion  47 , the second surface  46   b  of the base portion  46  is folded from the bent part  50 . This positions the distal end of the fan attaching portion  47  on the upper edge of the storage cover  49 . The upper edge of the storage cover  49  includes a shroud  53  that covers the distal end of the fan attaching portion  47 , which is folded from the bent part  50 . The shroud  53  has an open lower end to allow for insertion of the distal end of the fan attaching portion  47 . 
     A male or female hook-and-loop fastener  54   a,  which serves as the fan fastener, extends along the peripheral part of the fan attaching portion  47  excluding the bent part  50 . A hook-and-loop fastener  54   b  corresponding to the hook-and-loop fastener  54   a  extends along the peripheral part of the storage cover  49  excluding the bent part  50 . The hook-and-loop fastener  54   b  is also provided inside the shroud  53 . 
     As illustrated in  FIG.  6   , when the second surface  46   b  of the base portion  46  is folded from the bent part  50 , the distal end of the fan attaching portion  47  is forced into the shroud  53 . This couples the hook-and-loop fastener  54   a  and the hook-and-loop fastener  54   b.  In this manner, the fan unit bag  2  is formed prior to attachment to the backrest  13   b.  In this state, the fan unit bag  2  is attached to the rear surface of the backrest  13   b.    
     The four sides on the peripheral part of the second surface  46   b  of the base portion  46  are provided with male or female hook-and-loop fasteners  57   a  forming the fastener. The hook-and-loop fastener  57   a  is also arranged on the surface of the shroud  53 . The hook-and-loop fastener  57   a  is coupled to a corresponding hook-and-loop fastener  57   b  arranged on the base sheet  31 . That is, the hook-and-loop fastener  57   a  is arranged on the inner surface  40   b  on four sides surrounding a first region where the fan unit  41  is supported (region where the fan attaching portion  47  and the storage cover  49  overlap) and four sides surrounding a second region outside the first region (region above first region). In other words, the hook-and-loop fastener  57   a  is provided at the peripheral part (four sides) of the inner surface  40   b  and an intermediate portion, where the shroud  53  is located, extending between two vertical edges of the inner surface  40   b.    
     Further, the upper corners of the second surface  46   b  include base fastening eyelets  56   a  coupled to studs  56   b  of the base sheet  31 . 
     As illustrated in  FIG.  7   , the hook-and-loop fasteners  57   b  are arranged on the rear surface of the base sheet  31 of the backrest  13   b  at the four sides of the peripheral part in correspondence with the hook-and-loop fasteners  57   a.  The studs  56   b  are arranged on the upper corners of the back surface of the base sheet  31  in correspondence with the base fastening eyelets  56   a.  When a buckle of a reclining belt  61  extending from a longitudinal frame of the handle  19  is unbuckled, the fan unit bag  2  is arranged with the inner surface  40   b  facing the base sheet  31 . Then, the hook-and-loop fasteners  57   a  and  57   b  are coupled, and the base fastening eyelet  56   a  and the stud  56   b  are coupled. This arranges the fan base  42  of the fan unit bag  2  adjacent to the base sheet  31 . 
     As illustrated in  FIG.  8   , the coupling belts  59  of the inner sheet  32  are passed through the loops  58 , and eyelets of the coupling belts  59  are coupled to the studs  54 . The base coupling belts  60  are passed through and coupled to the loops  60   a  of the base sheet  31 . Further, the output cable  44  is extended out of the cable opening  49   a  and held by the cord cover  45  between the cable opening  49   a  and the battery pack  43 , which is stored in the pocket  48 . The connector  44   a  is connected to a cable extending from the battery pack  43 . The cord cover  45  is coupled to an edge of the base portion  46  and covers the output cable  44 . In this manner, the fan unit bag  2  is stably attached in a removable manner to the rear side of the backrest  13   b.  In this state, the flat portions  41   a  of the two fan units  41  face the base sheet  31  and the air permeable portion  37  of the inner sheet  32  through the base sheet  31 . 
     The operation of the stroller  1  and the fan unit bag  2  will now be described. 
     The stroller  1  carries the occupant seated on the seating unit  13  in a state in which the back of the occupant rests on the inner sheet  32  of the backrest  13   b  regardless of the height of the occupant. When this state continues, the air near the back or head of the occupant becomes hot and moist, and the riding comfort on the cushion  35  of the backrest  13   b  gradually deteriorates. 
     As illustrated in  FIG.  9   , when the fan unit bag  2  is attached to the backrest  13   b,  the flat portion  41   a  of each fan unit  41  faces the backrest  13   b  at the air permeable portion  37  in the backrest portion  34  of the inner sheet  32  through the base sheet  31 . When the fan units  41  are driven in this state, the fan units  41  function to draw air through the flat portions  41   a  and discharge air from the protruding portions  41   b.  This draws moisture and hot air from around the back and head of the occupant through the air permeable sheet  36   a  of the cover  36  into the cushion  35 . Then, the moisture and hot air in the cushion  35  are discharged through the air permeable portion  37  in the low air permeability sheet  36   b  and the air permeable base sheet  31  toward the rear of the stroller  1  by the fan units  41 . 
     The stroller  1  has the advantages described below. 
     (1) The fan unit bag  2  is easily attached in a removable manner to the backrest  13   b.  That is, the fan unit bag  2  can be easily attached to the backrest  13   b  when required such as during the summer. At other times, the fan unit bag  2  can be easily removed from the backrest  13   b.  When the fan unit bag  2  is attached to the backrest  13   b,  moisture and hot air can be released from the backrest  13   b  by driving the fan unit  41 . This cools the body of the occupant. 
     (2) The fan units  41  can be stably attached to the stroller  1  by attaching the fan unit bag  2 . Thus, vibrations produced when the stroller is moving or changes in the direction of the generated air current will not occur. This ensures that the occupant will be cool. 
     (3) In the fan unit bag  2 , the fan base  42 , serving as a base material, is formed by a sheet having low air permeability except at the portion where the fan units  41  are attached. This efficiently discharges air from the fan unit  41 . 
     (4) The fan unit bag  2  is coupled to the base sheet  31  by the hook-and-loop fasteners  57   a  and  57   b  serving as fasteners at the peripheral part of the inner surface  40   b.  This makes the space between the base sheet  31  and the fan unit bag  2  around the flat portion  41   a  of the fan unit  41  airtight and increases the efficiency for discharging air through the fan units  41 . 
     (5) The fan unit bag  2  is coupled to the base sheet  31  by the hook-and-loop fasteners  57   a  and  57   b.  Therefore, the fan unit bag  2  is more airtight than when the fan unit bag  2  is coupled to the base sheet  31  by buttons, hooks, or the like. 
     (6) In the backrest portion  34  of the inner sheet  32 , the cushion  35  is a high-repulsion cushion. A high-repulsion cushion is more repulsive than a normal cushion formed by a normal non-woven fabric because of the many voids included that results in high air permeability. Therefore, even if air is drawn into the air permeable portion  37  that is located below the backrest portion  34 , the air around the head of the occupant that is relatively far from the air permeable portion  37  can also be drawn toward the air permeable portion  37 . 
     (7) The inner sheet  32  including the cushion  35  is arranged on the backrest  13   b  and improves the riding comfort. Moisture and hot air is discharged from the cushion  35  by the fan unit bag  2 . 
     (8) The surface of the cover  36 , which covers the cushion  35 , at the side facing the base sheet  31  is formed by the low air permeability sheet  36   b  including the air permeable portion  37  where the fan unit  41  is arranged. Therefore, air is efficiently discharged from the cushion  35  through the air permeable portion  37 . The surface facing the base sheet  31  is formed from the sheet  36   b  having low air permeability except for the air permeable portion  37  and keeps the seating unit  13  warm under cold conditions such as during the winter when the fan unit bag  2  is removed. 
     (9) Regardless of size such as height of the occupant, at least part of the back of the occupant will rest on a position between the lower portion of the backrest  13   b  and the lowermost slits  22 , which is where the shoulder belts  21  are extracted from. The fan units  41  are arranged at such a position. Therefore, air is efficiently discharged from the cushion  35  by the fan units  41 . 
     (10) The air permeable portion  37  of the low air permeability sheet  36   b  is located between the lower portion of the backrest  13   b  and the extracted position of the shoulder belts  21 . This efficiently discharges air out of the cushion  35 . 
     (11) The fan attaching portion  47 , with the fan units  41  attached thereto, is simply folded toward the base portion  46  to easily attach the fan units  41  to the fan base  42  and position the fan units  41  in correspondence with the air permeable portion  37 . 
     (12) The hook-and-loop fasteners  54   a  and  54   b  serving as fan fasteners couple the fan attaching portion  47  and the base portion  46 . This makes the space surrounding the flat portion  41   a  of the fan unit  41  between the base sheet  31  and the fan unit bag  2  airtight and improves the efficiency for discharging air through the fan units  41 . 
     (13) The fan attaching portion  47  is coupled to the base portion  46  by the hook-and-loop fasteners  54   a  and  54   b.  Therefore, the fan attaching portion  47  is more airtight than when the fan attaching portion  47  is coupled to the base portion  46  by buttons, hooks, or the like. 
     (14) The hook-and-loop fasteners  57   a  and  57   b  are provided not only on the outer peripheral part of the inner surface  40   b  but also on the shroud  53 , which is an intermediate section extending between two vertical edge of the inner surface  40   b.  Therefore, the fan unit bag  2  is more firmly attached to the backrest  13   b,  and the surrounding of the fan units  41  are more airtight. 
     (15) In addition to the hook-and-loop fasteners  57   a  and  57   b,  the base sheet  31  and the fan unit bag  2  are coupled by the base fastening eyelets  56   a,  the studs  56   b,  and passage of the base coupling belts  60  through the loops  60   a.  Furthermore, the fan unit bag  2  and the inner sheet  32  are coupled to each other by passing the coupling belts  59  through the loops  58 . Thus, the fan unit bag  2  is coupled to both of the base sheet  31  and the inner sheet  32 . That is, the fan unit bag  2  is coupled to two members. Therefore, even if the fan unit bag  2  is separated from the base sheet  31 , the fan unit bag  2  remains coupled to the inner sheet  32 . Further, even if the fan unit bag  2  is separated from the inner sheet  32 , the fan unit bag  2  remains coupled to the base sheet  31 . Thus, the fan unit bag  2  will resist undesirable separation from the backrest  13   b.    
     (16) Even if the stroller  1 , to which the fan unit bag  2  is attached, is of a type with the base sheet  31  and the inner sheet  32  of the backrest  13   b  having air permeability, the fan base  42  is formed by a low air permeability sheet. Thus, moisture and hot air can be discharged efficiently from the backrest  13   b  by the fan units  41 . That is, even in a stroller in which the base sheet  31  has air permeability and the cover of the inner sheet  32  (surface that occupant rests on and the surface facing base sheet  31 ) has air permeability, the fan unit bag  2  efficiently discharges air from the backrest  13   b.    
     (17) The fan units  41  are arranged near the battery pack  43 . This facilitates the wiring of the output cable  44 . Further, the output cable  44  held by the cord cover  45  does not hinder movement of the stroller  1 . 
     (18) The fan unit  41  includes the flat portion  41   a  at the side facing the backrest  13   b.  Therefore, even if the fan unit  41  comes into contact with the back of the occupant on the seating unit  13  due to vibration or the like when the stroller  1  is moving, the back will contact the flat portion  41   a,  not the protruding portion  41   b.  Thus, the riding comfort will not be adversely affected. 
     The stroller may be modified as described below. 
     The number of fans attached to the fan unit bag  2  may be one, three, or more. 
     The fan unit  41  may be attached so that the protruding portion  41   b  faces the backrest  13   b.    
     The form of the fan unit  41  is not particularly limited. For example, the two surfaces of the fan unit  41  may both include the protruding portion  41   b  or both include the flat portion  41   a.    
     The battery pack  43  does not have to be stored in the pocket  48 . When the pocket  48  is not provided, the battery pack  43  may be stored in the storage portion  15  below the seating unit  13 . Alternatively, the battery pack  43  may be held by the operator or stored in a bag or the like hung on the handle  19  or the like. 
     The base sheet  31  may be a continuous sheet of the seat  13   a  and the backrest  13   b  or may be separate sheets of the seat  13   a  and the backrest  13   b.  Furthermore, when the seat  13   a  is formed by a plate such as a seat plate, the base sheet  31  includes only the backrest  13   b.    
     The fan unit bag  2  may be coupled only to the base sheet  31  or only to the inner sheet  32 . Furthermore, the fan unit bag  2  may be directly coupled to the frame of the backrest  13   b.    
     The base sheet  31  does have not have to be flexible as long as it is air permeable. The base sheet  31  may be air permeable only at a position facing the fan units  41  and other portions may have low air permeability. 
     The fan attaching portion  47  may be coupled to the base portion  46  by buttons, hooks, or the like without using the hook-and-loop fasteners  54   a  and  54   b  or in combination with the hook-and-loop fasteners  54   a  and  54   b.  A line fastener may be used instead of the hook-and-loop fasteners  54   a  and  54   b.    
     The fan attaching portion  47  does not have to folded onto the side of the second surface  46   b  of the base portion  46  and may be folded onto the side of the first surface  46   a.    
     The fan attaching portion  47  may be omitted. In this case, in the base portion  46 , the region of the storage cover  49  may be a low air permeability region provided with the attachment holes  51  that receive the fan units  41 . This will expose the protruding portions  41   b  of the fan units  41  but simplify the structure of the fan unit bag  2 . 
     In the inner sheet  32 , the location of the air permeable portion  37  is not particularly limited as long as it is in the backrest portion  34  and lower than the lowermost slits  22 . The air permeable portion  37  may be provided in the backrest portion  34  near the seat portion  33  or at a position spaced apart from the seat portion  33 . 
     The position of the fan units  41  is not particularly limited as long as the fan units  41  are in the backrest portion  34  and lower than the lowermost slits  22 . The fan units  41  may be provided in the backrest portion  34  near the seat portion  33  or at a position spaced apart from the seat portion  33 . 
     In the inner sheet  32 , the sheet at the side closer to the fan unit bag  2  and the base sheet  31  may also be formed by an air permeable sheet in the same manner as the sheet at the side closer to the occupant. In this case, the fan base  42  of the fan unit bag  2  may be formed by a low air permeability sheet, the entire cover  36  of the inner sheet  32  may be formed by an air permeable sheet, and the base sheet  31  may be formed by an air permeable sheet. That is, the portion corresponding to the low air permeability sheet  36   b  of the inner sheet  32  may be formed by a air permeable sheet. 
     The periphery of the air permeable portion  37  and the periphery of the flat portions  41   a  of the fan units  41  attached to the base portion  46  may be connected by a tube. For example, a tube may be arranged on the inner surface  40   b  of the fan unit bag  2  (second surface  46   b  of the base portion  46 ) so as to surround the two fan units  41 . When the fan unit bag  2  is attached to the rear of the backrest  13   b,  the distal end of the tube abuts against the periphery of the air permeable portion  37  through the base sheet  31 . This rectifies the flow of the drawn in air and discharges air from the cushion  35  more efficiently when driving the fan unit  41 . The tube can be elastic to increase adhesion with the base sheet  31  and the low air permeability sheet  36   b  around the air permeable portion  37  and soften contact with the back of the occupant. 
     The hook-and-loop fasteners  57   a  and  57   b  for attaching the fan unit bag  2  to the base sheet  31  may be provided at positions where the hook-and-loop fastener  57   a  on the surface of the shroud  53  and the corresponding hook-and-loop fastener  57   b  are located upward from the shroud  53 . The hook-and-loop fastener  57   a  provided in the intermediate section between the two vertical edges of the inner surface  40   b  and the corresponding hook-and-loop fastener  57   b  may be omitted. 
     The fan unit bag  2  may be coupled to the base portion  46  by buttons, hooks, or the like without using the hook-and-loop fasteners  57   a  and  57   b  or may be used in combination with the hook-and-loop fasteners  57   a  and  57   b.  Line fasteners may be used instead of the hook-and-loop fasteners  57   a  and  57   b.    
     As long as the hook-and-loop fasteners  57   a  and  57   b  surround the fan unit  41 , the hook-and-loop fasteners  57   a  and  57   b  do not have to be arranged in the pattern of the above-described example. Nevertheless, it is preferable that the hook-and-loop fasteners be arranged so that the base sheet  31  does not droop from the backrest  13   b.    
     The storage cover  49  may be a mesh sheet other than a net as long as it is air permeable. The storage cover  49  may be omitted. 
     In the stroller  1 , the fan unit bag  2  may be arranged on the lower surface of the seat  13   a.  In this case, in the seat portion  33  of the inner sheet  32 , the inner and outer sheets may be formed by air permeable sheets. The sheet at the side of the base sheet  31  may be formed by a low air permeability sheet, and the air permeable portion  37  having high air permeability may be located at a position opposing the fan unit  41 . In the stroller  1 , the fan unit bag  2  for the backrest may be attachable to the backrest  13   b,  and the fan unit bag conforming to the size of the seat  13   a  may also be attachable to the seat  13   a.    
     The user is not limited to an infant and may be an adult. The body supporting device may be a foldable or non-foldable chair, a sofa, a wheelchair, a vehicle seat, any of various types of beds, a mattress, or the like used by infants and adults. The present invention is also applicable to a pet cart that carries a pet such as a dog or a cat. 
     The fan unit bag may be attached to the backrest of a chair, a sofa, a wheelchair, or the like. Since various types of beds, mattresses, and the like are used by the user in a lying posture, the fan unit bag is only required to be attached to a position at the lower side of the body in the lying state. 
     Further, the fan unit bag may be attached to the rear side of a floor surface of the body support on where the pet is carried in the pet cart. 
     REFERENCE SIGNS LIST 
       1 ) stroller 
       2 ) fan unit bag 
       13 ) seating unit 
       13   a ) seat 
       13   b ) backrest 
       31 ) base sheet 
       32 ) inner sheet 
       35 ) cushion 
       36 ) cover 
       36   a ) air permeable sheet 
       36   b ) low air permeability sheet 
       37 ) air permeable portion 
       41 ) fan unit 
       41   a ) flat portion 
       41   b ) protruding portion 
       42 ) fan base 
       47 ) fan attaching portion 
       50 ) bent part 
       54   a,    54   b ) hook-and-loop fastener 
       57   a,    57   b ) hook-and-loop fastener