Abstract:
A vehicular seat having a seat cushion and a seat back, which are configured to be provided with air flow layers capable of being formed by a relatively simple step, is configured to be provided with: the seat cushion on which a vehicle occupant is seated; the seat back against which the vehicle occupant seated on the seat cushion rests his or her back; a fan disposed below the seat cushion; an air delivery duct for delivering to the seat cushion and the seat back, air delivered from the fan; and a seat cover for discharging the air delivered from the air delivery duct, from the surface of the seat cushion and the seat back to the side on which the vehicle occupant is seated. A plurality of groove spaces through which air delivered from the air delivery duct is caused to flow are formed inside the seat cover.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. national phase application filed under 35 U.S.C. § 371 of International Application No. PCT/JP2016/053737, filed Feb. 9, 2016, designating the United States, which claims benefit of the filing dates of JP 2015-026417, filed Feb. 13, 2015, and JP 2015-026427, filed Feb. 13, 2015, and JP 2015-031757, filed Feb. 20, 2015, each of which is hereby incorporated herein by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a vehicular seat, and more particularly, to a vehicular seat having a function of sending air to a seat cushion on which a vehicle occupant is seated and a seat back against which the seated vehicle occupant leans. 
         [0003]    Further, the present invention relates to a vehicular seat for a vehicle such as a passenger car, and more particularly, to a vehicular seat having a ventilation function to sending air (wind) to the seat on which a vehicle occupant is seated. 
       BACKGROUND ART 
       [0004]    A vehicular seat for a vehicle such as a passenger car has a seat cushion on which a vehicle occupant is seated and a seat back against which the seated vehicle occupant leans. As a structure having a function of sending wind from the vehicular seat to the side of the seated vehicle occupant, Patent literature 1 discloses a structure in which a ventilation layer to send wind from a blower via a duct to the inside of respective seat cover members of a seat cushion and a seat back is provided. 
         [0005]    The ventilation layer described in the Patent literature 1 has a truss structure in which plural columnar parts are provided between a surface side mesh and a back side mesh. The surface side mesh is bonded to the back surface of the seat cover. The surface side mesh, the back side mesh, and the plural columnar parts are integrally connected with elastically deformable resin. 
         [0006]    Further, in the vehicular seat, to maintain comfortability of the respective seat cushion on which the vehicle occupant is seated and the seat back against which the vehicle occupant seated on the seat cushion leans, means for sucking air from the surface of the seat and discharging the sucked air from another position of the seat is used. 
         [0007]    As an example of this structure, Patent literature 2 describes a structure where a blower is attached to the back side of a seat back. In a status where the blower is rotated, air in the vicinity of the surface of the seat back is sucked via a sucking duct from a hole formed in the vicinity of the surface of the seat back. The sucked air is blown to the surface of the back seat from a hole formed at a central part via a blowing duct. 
         [0008]    Further, in the vehicular seat, to maintain comfortability of the respective seat cushion on which the vehicle occupant is seated, and the seat back, against which the vehicle occupant seated on the seat cushion leans, means for sucking air from the surface of the seat and discharging the sucked air from another position of the seat is used. 
         [0009]    As an example of this structure, Patent literature 3 describes a structure where an exhauster is attached to the lower side of the seat cushion, and the exhauster is operated to suck air in the vicinity of the surfaces of the seat cushion and the seat back from a hole formed in the seat cushion and the seat back in a position near a side surface of the surface side, and blow the sucked air to the outside from the exhauster. 
       CITATION LIST 
     Patent Literature 
       [0000]    
       
         PTL 1: Japanese Patent Application Laid-Open No. 2012-1134 
         PTL 2: Japanese Patent Application Laid-Open No. 2010-52494 
         PTL 3: Japanese Patent Application Laid-Open No.2014-94623 
       
     
       SUMMARY OF INVENTION 
     Technical Problem 
       [0013]    In the structure described in the Patent literature 1, the wind is blown from the ventilation layer provided inside the respective seat cover members of the seat cushion and the seat back to the front side of the seat cover. However, in this structure, the ventilation layer is formed by integrally connecting the plural columnar parts, held between the surface side mesh and the back side mesh, and the surface side mesh, and the back side mesh. Although not clearly described in the Patent literature 1, it is conceivable that it requires a large number of steps to integrally form the ventilation layer having this structure. 
         [0014]    Further, in the lower part of the seat back, a lumber mechanism is provided to support the vehicle occupant&#39;s lumber when the vehicle occupant seated on the seat cushion leans against the seat back. An upper part (upper side) on the back surface of the seat back has comparatively sufficient space, and it is possible to suck and blow air from the surface of the seat back by using the blower and the duct. However, in the lower part (lower side) of the back surface of the seat back, provided with the lumber mechanism, the space is comparatively small, and it is difficult to set the duct there. 
         [0015]    Accordingly, the sucking and blowing of air from the surface of the seat back using the blower and the duct, as described in the Patent literature 2, are limited to the upper side of the seat back. In the lower part of the seat back provided with the lumber mechanism, it is impossible to suck and blow air from the front surface by using the duct. 
         [0016]    Further, as a structure to suck air from a seat cushion and a seat back and to blow the sucked air to the outside, Patent literature 3 describes a structure where an intake device is installed in a lower part of the seat cushion and the intake device, the seat cushion and the seat back are connected with a duct. 
         [0017]    The duct is connected, in communication with a ventilation groove having plural discharge air passages, formed in a pad of the seat back through to the front surface, to the seat back. 
         [0018]    Under the seat cushion on which the vehicle occupant is seated, a drive mechanism to slide the seat back and forth, a drive mechanism for reclining of the seat back and the like are provided, and many mechanisms are incorporated in the comparatively small space. Accordingly, to provide the intake device and the duct connected to the intake device under the seat cushion, the arrangement including the other parts is complicated. The number of parts is increased, and it takes time and effort to assemble the parts, which increases the cost. 
         [0019]    Further, the seat back is provided with a lumber mechanism part to support the lumber of the seated vehicle occupant. To provide the duct without interference with the lumber mechanism part, it is necessary to contrive the shape of the duct. 
         [0020]    Further, it is necessary to provide plural ducts for connection from the intake device respectively to the seat cushion and the seat back. This increases the number of parts, and prevents the reduction of assembling cost. 
         [0021]    The present invention provides a vehicular seat, having a seat cushion and a seat back, with a ventilation layer, which is capable of solving the problems in the conventional techniques, and which can be formed through comparatively simple steps. 
         [0022]    Further, the present invention is to solve the above-described problems in the conventional techniques, and to provide a vehicular seat which enables air sucking and blowing from a wide area of a seat back surface including a lower part of the seat back where a lumber mechanism is installed. 
         [0023]    Further, the present invention provides a vehicular seat which solves the above-described problems in the conventional techniques, and enables intake and discharge from the seat cushion and the seat back, with a small number of parts and with a comparatively simple structure. 
       Solution to Problem 
       [0024]    To solve the above-described problems, the present invention provides a vehicular seat comprising: a seat cushion on which a vehicle occupant is seated; a seat back against which the vehicle occupant seated on the seat cushion leans; a fan provided in a lower part of the seat cushion; an air duct that sends air sent from the fan to the seat cushion and the seat back; and a seat cover that discharges the air sent from the air duct from surfaces of the seat cushion and the seat back to the side on which the vehicle occupant is seated. A plurality of groove spaces to pass the air sent from the air duct are formed inside the seat cover. 
         [0025]    Further, to solve the above-described problems, the present invention provides a vehicular seat comprising: a seat cushion on which a vehicle occupant is seated; a seat back against which the vehicle occupant seated on the seat cushion leans; a fan that sends air; an air duct that sends the air sent from the fan to the seat cushion and the seat back; and a seat cover that discharges the air, passed through a plurality of groove space to pass the air sent from the air duct, from breathable surfaces of the seat cushion and the seat back, to the side where the vehicle occupant is seated. 
         [0026]    Further, to solve the above-described problems, the present invention provides a vehicular seat comprising: a seat cushion on which a vehicle occupant is seated; and a seat back against which the vehicle occupant seated on the seat cushion leans. The seat back has: a breathable seat cover provided on a surface against which the vehicle occupant leans; a pad member, the surface of which is covered with the seat cover, and in which a plurality of ventilation holes are formed in vertical and lateral directions; a lumber mechanism part to support the lumber of the vehicle occupant seated on the seat cushion; a blower provided on the back surface side of the pad member; a duct connecting at least one of the plurality of ventilation holes provided in the pad member, in a position upper from the lumber mechanism part, with the blower; and a cover, covering the blower, the duct, and the lumber mechanism part, to form tightly closed space along with the back surface side of the pad member. 
         [0027]    Further, to solve the above-described problems, the present invention provides a vehicular seat comprising: a seat cushion on which a vehicle occupant is seated; and a seat back against which the vehicle occupant seated on the seat cushion leans. The seat back has: a breathable seat cover provided on the surface against which the vehicle occupant leans; a pad member, the surface of which is covered with the seat cover, and in which a plurality of ventilation holes are formed; a blower provided on the back surface side of the pad member; and a duct connecting at least one hole among the plurality of ventilation holes provided in the pad member, in an upper part of the pad member. Air sucking or air blowing from the surface of the seat cover, through the ventilation hole connected with the duct formed in the upper part of the pad member, is performed using the duct connected with the blower. Further, air sucking or air blowing from the surface of the seat cover is performed through the ventilation hole formed in a lower part of the pad member, without using the duct. 
         [0028]    Further, to solve the above-described problems, the present invention provides a vehicular seat comprising: a seat cushion on which a vehicle occupant is seated; a seat back against which the vehicle occupant seated on the seat cushion leans; and a duct connecting the seat cushion and the seat back. The seat back has: a breathable seat cover provided on the surface against which the vehicle occupant leans; a pad member the surface of which is covered with the seat cover, and in which a plurality of ventilation holes are formed; a lumber mechanism part to support the lumber of the vehicle occupant seated on the seat cushion; a blower provided on the back surface side of the pad member; and a cover, covering the blower and the lumber mechanism part, to form tightly closed space along with the back surface side of the pad member. The seat cushion has: a breathable seat cover provided on the surface on which the vehicle occupant is seated; and a pad member the surface of which is covered with the seat cover, and in which a ventilation groove is formed. The duct connects the blower in the seat back and the groove formed in the seat cushion via the cover. 
         [0029]    Further, to solve the above-described problems, the present invention provides a vehicular seat comprising: a seat cushion on which a vehicle occupant is seated; a seat back against which the vehicle occupant seated on the seat cushion leans; and a blower. The seat back has: a breathable seat cover provided on the surface against which the vehicle occupant leans; a pad member the surface of which is covered with the seat cover, and in which a plurality of ventilation holes are formed; a lumber mechanism part to support the lumber of the vehicle occupant seated on the seat cushion; and a cover covering the lumber mechanism part, to form tightly closed space along with the back surface side of the pad member. The seat cushion has: a breathable seat cover provided on the surface on which the vehicle occupant is seated; and a pad member the surface of which is covered with the seat cover, and in which a ventilation groove is formed. The blower has a first duct connected with the groove of the pad member in the seat cushion and a second duct connected with the cover of the seat back. 
       Advantageous Effects of Invention 
       [0030]    According to the present invention, it is possible to provide a vehicular seat, having a seat cushion and a seat back, with a ventilation layer which can be formed through comparatively simple steps. 
         [0031]    Further, according to the present invention, it is possible to perform air sucking and blowing from a wide area of a seat back surface including a lower part of the seat back in which the lumber mechanism is installed. 
         [0032]    Further, according to the present invention, it is possible to provide a vehicular seat which enables intake and discharge from the seat cushion and the seat back, with a small number of parts and with a comparatively simple structure. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0033]      FIG. 1  is a perspective view showing a schematic structure of a vehicular seat according to the example 1 of the present invention; 
           [0034]      FIG. 2  is a cross sectional view showing the schematic structure of the vehicular seat according to the example 1 of the present invention; 
           [0035]      FIG. 3  is a perspective view showing a structure of a seat cover of the vehicular seat according to the example 1 of the present invention; 
           [0036]      FIG. 4  is a cross sectional view showing the structure of the seat cover of the vehicular seat according to the example 1 of the present invention; 
           [0037]      FIG. 5  is an enlarged view of a part A in  FIG. 2  showing the relationship between the seat cover and an air duct in the vehicular seat according to the example 1 of the present invention; 
           [0038]      FIG. 6  is a cross sectional view along a line B-B in  FIG. 5  showing the relationship between the seat cover and the air duct in the vehicular seat according to the example 1 of the present invention; 
           [0039]      FIG. 7  is an enlarged view of the part A in  FIG. 2  showing a modification of the relationship between the seat cover and the air duct in the vehicular seat according to the example 1 of the present invention; 
           [0040]      FIG. 8  is a cross sectional view along a line C-C in  FIG. 7  showing another modification of the relationship between the seat cover and the air duct in the vehicular seat according to the example 1 of the present invention; 
           [0041]      FIG. 9  is a cross sectional view showing a schematic structure of the seat back of the vehicular seat according to the example 2 of the present invention; 
           [0042]      FIG. 10  is a perspective view showing a schematic structure of a pad member of the seat back in the vehicular seat according to the example 2 of the present invention; 
           [0043]      FIG. 11  is a cross sectional view showing a schematic structure of the seat back in the vehicular seat according to the example 3 of the present invention; 
           [0044]      FIG. 12  is a cross sectional view showing a schematic structure of the seat back in the vehicular seat according the example 4 of the present invention; 
           [0045]      FIG. 13  is a cross sectional view showing a schematic structure of the vehicular seat according to the example 5 of the present invention; 
           [0046]      FIG. 14  is a perspective view showing a schematic structure of the pad member in the vehicular seat according to the example 5 of the present invention; 
           [0047]      FIG. 15  is a cross sectional view showing a schematic structure of the vehicular seat according to the example 6 of the present invention; 
           [0048]      FIG. 16  is a cross sectional view showing a schematic structure of the vehicular seat according to the example 7 of the present invention; and 
           [0049]      FIG. 17  is a cross sectional view showing a schematic structure of the vehicular seat according to the example 8 of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0050]    Hereinbelow, examples of the present invention will be described using the drawings. 
       Example 1 
       [0051]    In the present example, a vehicular seat, where a skin layer of seat cushion and seat back in a vehicular seat for vehicle such as a passenger car is formed with a skin member, a soft intermediate layer member, and a backside member, will be described. In the intermediate layer, a ventilation passage is formed and a hole communicating with the skin member side is formed in the ventilation passage. Wind sent from a blower via the air duct is sent to the ventilation passage in the intermediate member. The air is discharged via the hole from the skin member side to the side on which the vehicle occupant is seated, from the surfaces of the seat cushion and the seat back. 
         [0052]      FIG. 1  shows the outer appearance of a vehicular seat  100  as the subject of the present invention. The vehicular seat  100  has a seat cushion  110  on which a vehicle occupant (not shown) is seated, a seat back  120  against which the vehicle occupant seated on the seat cushion  110  leans, and a head rest  130  to support the vehicle occupant&#39;s head. 
         [0053]      FIG. 2  schematically shows a cross section of the vehicular seat  100 . Reference numeral  111  denotes a seat cover of the seat cushion  110 , and  112 , a urethane pad member of the seat cushion  110 . Further, numeral  121  denotes a seat cover of the seat back  120 , and  122 , a urethane pad member of the seat back  120 . In  FIG. 2 , illustration of the head rest  130  and illustration of a frame member are omitted. 
         [0054]    The vehicular seat  100  has a fan  140  as a blower and an air duct  141  under the seat cushion  110 . The fan  140  sucks air in the vehicle under the seat cushion  110 , and discharges the air to the air duct  141  side. The air (wind) sucked from the fan  140  and discharged to the air duct  141  side is sent from the surfaces of the seat covers  111  and  121  of the seat cushion  110  and the seat back  120  to the side where the vehicle occupant is seated. 
         [0055]      FIG. 3  shows the structure of the seat covers  111  and  121 . The seat covers  111  and  121  have a seat-surface side skin member  31 , an intermediate layer member  32 , and a pad side member  33 . 
         [0056]    The seat-surface side skin member  31  is formed with breathable fabric or skin having breathability with a large number of holes  311 . On the other hand, the pad side member  33  is formed with non-breathable material such as non-woven fabric or a resin seat. 
         [0057]    In the intermediate layer member  32 , formed with an elastic material such as urethane, plural recesses  321  are formed along the longitudinal direction of the seat cushion  110  and the vertical direction of the seat back  120 . Further, holes  323  are formed in an upper surface  322  of the recess  321 . It is possible to change the positions from which the air is sent from the surfaces of the seat covers  111  and  121  to the side where the vehicle occupant is seated by changing the positions of the holes  323 . 
         [0058]      FIG. 4  shows a cross section of the seat covers  111  and  121 . The arrow in the figure indicates the flow of the air sent from the fan  140  via the air duct  141 . In the figure, the air sent from the right side direction flows along spaces (groove spaces) formed with the recesses  321  formed in the intermediate layer member  32  and the non-breathable pad side member  33 . The recesses  321  are formed such that an end  324  of the intermediate layer member  32  is left. Accordingly, the air sent from the right side in the figure along the spaces formed with the recesses  321  and the pad side member  33  does not escape to the left side. 
         [0059]    The air flew along the spaces formed with the recesses  321  and the pad side member  33  passes from the large number of holes  323  formed in the upper surface  322  of the recesses  321  in the intermediate layer member  32  through the breathable seat-surface side skin member  31 , and flows from the seat-surface side skin member  31  to the outside where the vehicle occupant is seated. 
         [0060]    In this manner, as the air sent from the fan  140  flows from the seat-surface side skin member  31  covering the surfaces of the seat cushion  110  and the seat back  120  to the outside where the vehicle occupant is seated, the seat cushion  110  and the seat back  120  breathe well, and provide comfortableness to the seated vehicle occupant. 
         [0061]      FIG. 5  shows a part A in  FIG. 2 , i.e., an enlarged view of the structure of a connecting portion among the air duct  141 , and the seat cover  111  on the seat cushion  110  side, and the seat cover  121  on the seat back  120  side. The part around the end of the air duct  141  is held between the seat cover  111  on the seat cushion  110  side and the seat cover  121  on the seat back  120  side. 
         [0062]    In this structure, as indicated with the arrow, the air sent from the fan  140  is discharged from the end of the air duct  141  to space  210  held between the seat cover  111  on the seat cushion  110  side in the vicinity of the end of the air duct  141  and the seat cover  121  on the seat back  120  side in the vicinity of the end of the air duct  141 . The air discharged to the space  210  passes from the breathable seat-surface side skin member  31  of the seat cover  111  and the seat cover  121  through the large number of holes  323  formed in the intermediate layer member  32  to the recess  321  side. 
         [0063]    Since the recesses  321  are formed such that the end  324  of the intermediate layer member  32  is left, as described above, the air flew to the recess  321  side flows to the seat cushion  110  side or the seat back  120  side, along the spaces formed with the recesses  321  and the non-breathable pad side member  33  as described in  FIG. 4 , passes from the large number of holes  323  formed in the upper surface  322  of the recesses  321  in the intermediate layer member  32  through the breathable seat-surface side skin member  31 , and flows from the seat-surface side skin member  31  to the outside where the vehicle occupant is seated. 
         [0064]      FIG. 6  shows a cross section along a line B-B in  FIG. 5 , i.e., a cross section of the connecting portion among the air duct  141 , the seat cover  111  on the seat cushion  110  side, and the seat cover  121  on the seat back  120  side. The seat cover  111  on the seat cushion  110  side and the seat cover  121  on the seat back  120  side are sewn, with the air duct  141  between the seat covers, in positions  151  and  152  on the both sides. With this configuration, in the air discharged from the air duct  141  to the space  210 , it is possible to reduce the amount of the air leaked to the outside from a gap among the air duct  141 , the seat cover  111  and the seat cover  121 , and to increase the amount of the air which flows to the side of the recesses  321  in the intermediate layer member  32 . 
         [0065]      FIG. 7  shows a modification of the structure of the connecting portion among the air duct  141 , the seat cover  111  on the seat cushion  110  side and the seat cover  121  on the seat back  120  side. 
         [0066]    In the example shown in  FIG. 7 , the lengths of the seat-surface side skin member  31  and the intermediate layer member  32  of the seat cover  111  and the seat cover  121  are shorter than the non-breathable pad side member  33 . The air duct  141  is held with the pad side members  33 , and the pad side members  33  on the both sides of the air duct  141  are sewn in positions  161  and  162  on the both sides shown in  FIG. 8  as in the case of  FIG. 6 . In this case, the recesses  321  in the intermediate layer member  32  are formed through the intermediate layer member  32 . The end of the recesses  321  formed in the intermediate layer member  32  is opened in space  220  surrounded with the end of the air duct  141 , the seat cover  111 , and the seat cover  121 . 
         [0067]    In this structure, the air sent from the fan  140  is discharged from the end of the air duct  141  to the space  220 . As indicated with the arrow, the air discharged to the space  220  flows from the opening of the recesses  321  in the end surface of the intermediate layer member  32  along the spaces formed with the recesses  321  and the non-breathable pad side member  33 , to the seat cushion  110  side or the seat back  120  side. Then the air passes from the large number of holes  323  formed in the upper surface  322  of the recesses  321  in the intermediate layer member  32  through the breathable seat-surface side skin member  31 , and flows from the seat-surface side skin member  31  to the outside where the vehicle occupant is seated. 
         [0068]    It is possible to change the amount of air flow and its distribution by changing the size distribution, the number of holes  323 , and interval (arrangement) of holes formed in the upper surface  322  of the recesses  321  in the intermediate layer member  32 . For example, it is possible to set the amount of the air which flows from the seat back  120  side to a smaller amount with respect to the amount of the air which flows from the seat cushion  110  side by reducing the size and the number of the holes  323  formed in the intermediate layer member  32  on the seat back  120  side comparing to the seat cushion  110 . 
         [0069]    Further, even in the same plane of the seat cushion  110  or the seat back  120 , it is possible to set the amount of the air which flows from the central part to a larger amount, or conversely, to a smaller amount, with respect to the peripheral part by adjusting the distribution of the size of the holes  323  and interval (arrangement) and the like of the holes  323  in the intermediate layer member  32 . 
         [0070]    According to the present example, the air, sent from the fan  140  and passed through the air duct  141  to the side of the seat cover  111  and the seat cover  121 , flows along the spaces formed with the recesses  321  formed in the intermediate layer member  32  of the seat cover  111  and the seat cover  121  and the non-breathable pad side member  33 . Accordingly, upon formation of the intermediate layer member  32 , it is possible to form the recesses  321  at the same time, and it is possible to form air flow passages with a comparatively low cost. 
         [0071]    Next, it is configured such that the back surface of the seat back has a closed structure, then in an upper part of the seat back, air sucking or air blowing from the surface is performed by using a duct, and in a lower part of the seat back, the air sucking or the air blowing from the seat back surface is performed without duct. With this configuration, a vehicular seat, in which even in the lower part of the seat back where a lumber mechanism is installed, it is possible to perform air sucking or air blowing from the seat back surface, and it is possible to perform air sucking and air blowing in a comparatively wide region of the seat back surface or in an arbitrary position, will be described in examples from 2 to 4. 
       Example 2 
       [0072]      FIG. 9  schematically shows a cross section of the seat back  120 - 1  of the vehicular seat  100 . Numeral  2121  denotes a breathable seat cover of the seat back  120 - 1 . Numeral  2122  denotes a urethane pad member of the seat back  120 - 1 . An air blowing hole  2123  is formed in the upper side of the pad member  2122 , further, a large number of air sucking holes  2124  are formed in the lower side of the pad member  120 - 1 . 
         [0073]    In the structure shown in  FIG. 9 , for the sake of simplification of the explanation, illustration of mechanical parts is omitted. 
         [0074]    On the back side of the seat back  120 - 1 , an air duct  2211  the end of which is fitted in the air blowing hole  2123 , a blower  2212 , and a lumber mechanism part  2213  as a part of a lumber mechanism are provided. These members are tightly closed up with a back cover  2210 . As the blower  2212 , a sirocco fan is used. When the blower  2212  using this sirocco fan is operated, the air is sucked from the left side surface of the blower  2212  in  FIG. 9 . The sucked air is discharged to the side of the air duct  2211  attached to the upper surface of the blower  2212 . 
         [0075]    With this structure, when the blower  2212  is operated, the blower  2212  sucks the air in space  2214  closed with the back cover  2210  and sends the air to the air duct  2211  side. The air is sent from the air duct  2211  through the air blowing hole  2123 , and as indicated with an arrow D, blown from the breathable seat cover  2121  to the surface side of the seat cover  2121 . 
         [0076]    The end of the air duct  2211  is tightly fitted in the air blowing hole  2123 . Further, a portion of the air duct  2211  for connection with the blower  2212  is closely attached to the blower  2212  side. With this structure, respectively different pressure statuses are caused inside the air duct  2211  and the outside the air duct  2211 , separated from the space  2214  inside the back cover  2210 . In this status, the air sent from the blower  2212  to the air duct  2211  is blown through the air blowing hole  2123  to the surface side of the seat cover  2121 , without returning into the space  2214  closed with the back cover  2210 . 
         [0077]    On the other hand, in the space  2214  closed with the back cover  2210  in which the air has sucked, the air pressure is lower than the atmospheric pressure. As indicated with an arrow E, the air is sucked from the large number of air sucking holes  2124  formed in the lower side of the pad member  2120  via the breathable seat cover  2121 . 
         [0078]    In this manner, as the air duct  2211  is used in the space  2214  closed with the back cover  2210 , it is possible, by operating the blower  2212 , to blow the air from the air duct  2211  through the air blowing hole  2123  to the surface side of the seat cover  2121 , and at the same time, to suck the air from the large number of air sucking holes  2124  formed on the lower side of the pad member  2122  via the breathable seat cover  2121  into the inside the space  2214  closed with the back cover  2210 , efficiently, and in a stable manner. 
         [0079]      FIG. 10  shows a perspective view of the pad member  2212 . In the upper part of the pad member  2122 , the air blowing hole  2123  is formed, and in the lower part, the large number of air sucking holes  2124  are formed. The air blowing hole  2123  and the air sucking holes  2124  are formed through the pad member  2122 . 
         [0080]    Note that in the example shown in  FIG. 10 , only one air blowing hole  2123  is formed. However, plural air blowing holes  2123  may be provided. In this case, the end of the air duct  2211  are branched in correspondence with the number of air blowing holes  2123  formed in the pad member  2122 , and the respective ends are tightly fitted in the air blowing holes  2123 . 
         [0081]    Further, in the example shown in  FIG. 10 , the plural air sucking holes  2124  are provided in the lower part of the pad member  2122 . Further, the air sucking hole  2124  may be provided in the vicinity of the air blowing hole  2123  or in the central part of the pad member  2122 . Further, the air sucking holes  2124  may be provided in the entire surface of the pad member  2122 . 
         [0082]    In this manner, by separating the air sent with the blower  2212  from the air sucked in the blower  2212  by using the air duct  2211 , it is unnecessary to provide a duct on the air sucking side of the blower  2212 . It is possible to provide the air sucking holes  2124  in the lower part of the seat back  120  in which the lumber mechanism part  2213  is installed. 
         [0083]    With this configuration, it is possible to provide the air blowing hole  2123  and the air sucking holes  2124  in arbitrary positions with respect to the seat back  120 . It is possible to prevent confinement of heat around the lumber of the vehicle occupant and to efficiently perform dehumidification. 
       Example 3 
       [0084]    In the example 2, the example using the air duct  2211  has been described. In the present example, an example using an air sucking duct will be described using  FIG. 11 . 
         [0085]      FIG. 11  shows a cross section of the seat back  120 - 2  according to the present example. In the structure shown in  FIG. 11 , the constituent elements the same as those described in the example 2 have the same numerals. The difference from the example 2 is the structure of the back side of the seat back  120 - 2 . In the example 2, the hole  2123  has been described as an air blowing hole. In the example 3, it is an air sucking hole. Further, the large number of holes  2124  has been described as air sucking holes. In the example 3, they are described as air blowing holes. 
         [0086]    In the structure shown in  FIG. 11 , on the back side of the seat back  120 - 2 , there are an air sucking duct  2221  with its end fitted in the air sucking hole  2123 , a blower  2222 , and a lumber mechanism part  2213 . They are provided inside space  2224  tightly closed with the back cover  2220 . The air sucking duct  2221  is closely connected to the air sucking side of the blower  2222 . The air discharging side of the blower  2222  is opened to the space  2224  tightly closed with the back cover  2220 . As the blower  2222 , a sirocco fan is used as in the case of the example 2. 
         [0087]    In this structure, when the blower  2222  is operated, air is sucked with the blower  2222 , from the air sucking duct  2221  through the air sucking hole  2123  via the breathable seat cover  2121 , from the surface side of the seat cover  2121 , as indicated with an arrow F. The sucked air is discharged from the blower  2222  into the space  2224  tightly closed with the back cover  2220 . In the space  2224  tightly closed with the back cover  2220 , into which the air has been discharged from the blower  2222 , the air pressure is higher than the atmospheric pressure. The air is blown, from the air blowing holes  2124  via the breathable seat cover  2121 , to the surface side of the seat cover  2121 . 
         [0088]    The end of the air sucking duct  2221  is tightly fitted in the air sucking hole  2123 . With this configuration, the air, discharged from the blower  2222  into the space  2224  tightly closed with the back cover  2220 , is passed through the air blowing holes  2124 , without returning to the air sucking duct  2221  side, and is blown to the surface side of the seat cover  2121  as indicated with an arrow G. 
         [0089]    In this manner, as the air sucking duct  2211  is used in the space  2214  closed with the back cover  2210 , it is possible to suck air from the air sucking duct  2221  through the air sucking hole  2123 , from the surface side of the seat cover  2121 , by operating the blower  2222 , and at the same time to blow the air in the space  2224  closed with the back cover  2210  from the large number of air blowing holes  2124  via the breathable seat cover  2121 , to the surface side of the seat cover  2121 , efficiently, and in a stable manner. 
         [0090]    The arrangement of the holes  2123  and  2124  formed in the pad member  2122  in the present example is the same as that described in the example 2 using  FIG. 10 , and the difference is operation of air blowing or air sucking. Accordingly, the explanation of the arrangement will be omitted. 
         [0091]    According to the present example, it is possible to provide the air blowing holes  2124  and the air sucking hole  2123  in arbitrary positions with respect to the seat back  120 - 2 . It is possible to prevent confinement of heat around the lumber of the vehicle occupant and to perform dehumidification efficiently. 
       Example 4 
       [0092]    In the example 2, an example using the air duct  2211  has been described, and in the example 3, an example using the air sucking duct  2221  has been described. In the present example, an example where one duct is used as an air duct and an air sucking duct will be described. 
         [0093]      FIG. 12  shows a cross sectional view of the seat back  120 - 3  according to the present example. In the structure shown in  FIG. 12 , the constituent elements the same as those described in the example 2 have the same numerals. The difference from the example 2 is the structure of the back side of the seat back  120 - 3 . In the example 2, the hole  2123  has been described as an air blowing hole. In the example 4, it is an air blowing hole and an air sucking hole. Further, in the example 2, the large number of holes  2124  has been described as air sucking holes. In the example 4, they are used as air blowing holes and air sucking holes. 
         [0094]    In the structure shown in  FIG. 12 , on the back side of the seat back  120 - 3 , there are an air sucking and air blowing duct  2231  with its end fitted in the hole  2123  used as an air sucking hole and an air sucking hole, a blower  2232 , and a lumber mechanism part  2213 . They are provided in space  2234  tightly closed with the back cover  2230 . The duct  2231  is connected to one side of the blower  2232 . The other side of the blower  2232  is opened to the space  2234  tightly closed with the back cover  2230 . In the example 2 and the example 3, the example using the sirocco fan as the blower  2212  or  2222  has been described. In the present example, an axial flow fan is used. 
         [0095]    The blower  2232  using the axial flow fan changes the rotational direction of the fan by changing the electric polarity, which changes air flow direction. 
         [0096]    That is, by forward-rotating the axial flow fan of the blower  2232 , as in the case described in the example 2, the air in the space  2234  tightly closed with the back cover  2230  is sucked with the blower  2232 , and the sucked air is blown from the blower  2232  to the duct  2231  side. The air blown to the duct  2231  side is passed through the hole  2123 , and blown via the breathable seat cover  2121 , from the surface side of the seat cover  2121 , as indicated with an arrow H. 
         [0097]    The end of the duct  2231  is tightly fitted in the hole  2123 . With this configuration, the air sent from the blower  2232  to the duct  2231  is blown through the hole  2123 , without returning to the space  2234  closed with the back cover  2230 , to the surface side of the seat cover  2121 , as indicated with the arrow H. 
         [0098]    On the other hand, in the space  2234  closed with the back cover  2230  in which the air has been sucked, the air pressure is lower than the atmospheric pressure. The air is sucked from the large number of holes  2124  formed in the lower part of the pad member  2122 , via the breathable seat cover  2121 , as indicated with an arrow I. 
         [0099]    Further, by reverse-rotating the axial flow fan of the blower  2232 , the air on the duct  2231  side is sucked with the blower  2232 , as in the case described in the example 3. The sucked air is blown into the space  2234  tightly closed with the back cover  2230  on the opposite side to the duct  2231 . That is, by reverse-rotating the axial flow fan of the blower  2232 , the air is sucked from the duct  2231  through the hole  2123 , from the surface side of the seat cover  2121 , and at the same time, the air in the space  2234  closed with the back cover  2230  is blown from the large number of holes  2124  to the surface side of the breathable seat cover  2121  in the opposite direction to the direction of the arrow I. 
         [0100]    In this manner, by using the axial flow fan as the blower  2232 , it is possible to change the direction to send the air from the blower  2232  by changing the polarity of electric pressure applied to the blower  2232 . This enables selection between an air sucking position and an air blowing position on the surface of the seat back. 
         [0101]    Next, the vehicular seat, in which the back surface of the seat back has a closed structure, the blower and the cushion seat are connected with a duct, air sucking or air blowing from the surface of the seat cushion is performed via the duct, and air sucking or air blowing from the surface of the seat back is performed without duct, capable of air sucking or air blowing from the both surfaces on the seat cushion side and the seat back side, by using one blower and one duct, will be described in the examples 5 to 8. 
         [0102]    Further, in the following examples, it makes possible to perform air sucking from the surface of the seat cushion and air blowing from the surface of the seat back, or on the contrary, to perform air blowing from the surface of the seat cushion and air sucking from the surface of the seat back, simultaneously, using one blower and one duct. 
       Example 5 
       [0103]      FIG. 13  schematically shows a cross section of the seat cushion  110 - 1  and the seat back  120 - 4  in the vehicular seat  100  according to the present example. In  FIG. 13 , for the sake of simplification of the explanation, illustration of the head rest  130  and illustration of mechanical parts of the seat cushion  110 - 1  and the seat back  120 - 4  are omitted. 
         [0104]    The seat cushion  110 - 1  has a breathable seat cover  5111  and a urethane pad member  5112 . An air blowing or air sucking groove  5113  is formed in the pad member  5112 . The groove  5113  becomes an air passage upon air blowing to the surface of the seat cushion  110 - 1  or air sucking via the breathable seat cover  5111  covering the surface. 
         [0105]    The seat back  120 - 4  has a breathable seat cover  5121  and a urethane pad member  5122 . Air blowing or air sucking holes  5123  are formed in the pad member  5122 . 
         [0106]    A back cover  5124  is attached to the back side of the seat back  120 - 4 , and space  5125  surrounded with the pad member  5122  and the back cover  5124  is tightly closed. A lumber mechanism part  5126  as a part of the lumber mechanism, a blower  5210 , and a duct  5213  connected to the discharge side of the blower  5210  are installed in the tightly closed space  5125 . As the blower  5210 , a sirocco fan is used. An intake  5211  of the blower  5210  is opened to the side of the tightly closed space  5125 . Actually, various mechanism parts are installed in this tightly closed space  5125 . However, in  FIG. 13 , for the sake of simplification of the explanation, illustration of these parts is omitted. 
         [0107]    The duct  5211  connected to the blower  5210  extends through the back cover  5124  to the outside, and its end extends into the groove  5113  formed in the pad member  5112  on the seat cushion  110 - 1  side, and is fixed with an unillustrated means. 
         [0108]    In this structure, when the blower  5210  is operated, the blower  5210  sucks the air from the intake  5211 , as indicated with an arrow J 2 , into the space  5125  closed with the back cover  5124 , to send the air to the side of the duct  5213  connected to the discharge side. The air sent to the duct  5213  enters the groove  5113  of the seat cushion  110 - 1 , as indicated with an arrow J 3 . The air entered the groove  5113  is blown from the breathable seat cover  5111  to the surface side of the seat cover  5111 , as indicated with an arrow J 4 . 
         [0109]    On the other hand, in the space  5125  closed with the back cover  5124  in which the air is sucked with the blower  5210 , the air pressure is lower than the atmospheric pressure. As a result, the air is sucked from the large number of holes  5123  formed in the pad member  5122  via the breathable seat cover  5121  of the seat back  120 - 4 , as indicated with an arrow J 1 . 
         [0110]    In this manner, by sucking air from the seat cover  5121  side of the seat back  120 - 4  into the space  5125  closed with the back cover  5124 , then sending the air through the duct  5213  to the seat cushion  110 - 1  side, and injecting the air from the seat cover  5111  of the seat cushion  110 - 1 , it is possible to perform air sucking with the seat back  120 - 4  and at the same time to perform air blowing with the seat cushion  110 - 1 , using only one blower  5210  and one duct  5213 . 
         [0111]    Note that in the structure shown in  FIG. 13 , in the tightly closed space  5125  on the back of the seat back  120 - 4 , the blower  5210  is provided in a position lower than the lumber mechanism part  5126 , however, the blower  5210  may be provided in an upper position from the lumber mechanism part  5126 . 
         [0112]      FIG. 14  shows a perspective view of the pad member  5112  on the seat cushion  110 - 1  side and the pad member  5122  on the seat back  120 - 4  side. An air blowing groove  5113  is formed in the pad member  5112  on the seat cushion  110 - 1  side. Further, a large number of air sucking holes  5123  are formed in the pad member  5122  on the seat back  120 - 4  side. The air sucking holes  5123  are formed through the pad member  5122 . 
         [0113]    As described above, according to the present example, as the back surface of the seat back  120 - 4  provided with the lumber mechanism part  5126  and the blower  5210  is tightly closed, a duct to suck air from the surface of the seat back  120 - 4  is unnecessary. It is possible to simultaneously perform air sucking in the seat back  120 - 4  and air blowing in the seat cushion  110 - 1 , with a more simple structure using one blower  5210  and one duct  5213 . 
       Example 6 
       [0114]    As an example 6 of the present invention, an opposite case to the example 5, i.e., a structure to suck air from the seat cushion  110 - 1  side and blow the air from the seat back  120 - 4  side, will be described using  FIG. 15 . In the structure shown in  FIG. 15 , the constituent elements the same as those described in the example 5 using  FIG. 13  have the same numerals, and explanations of those elements will be omitted to avoid overlapping of explanation. In the structure shown in  FIG. 15 , the difference from the structure described in  FIG. 13  is that a duct  5214  is attached to the intake  5211  side of the blower  5210 . As the blower  5210 , as in the case of the example 5, a sirocco fan is used. 
         [0115]    In the structure shown in  FIG. 15 , when the blower  5210  is operated, the blower  5210  sucks the air on the surface side of the seat cover  5111  from the breathable seat cover  5111  via the duct  5214  connected to the intake  5211  and the groove  5113  of the seat cushion  110 - 1 , as indicated with an arrow K 1 . 
         [0116]    The air sucked from the surface side of the seat cover  5111  passes through the duct  5214  as indicated with an arrow K 2 , then is sucked from the intake  5211  into the blower  5210  as indicated with an arrow K 3 , and is discharged into the space  5125  closed with the back cover  5124  as indicated with an arrow K 4 . 
         [0117]    In the space  5125  closed with the back cover  5124  in which the air has been discharged with the blower  5210 , the air pressure is higher than the atmospheric pressure. As a result, the air is blown from the large number of holes  5123  formed in the pad member  5122  via the breathable seat cover  5121  of the seat back  120 - 4 , to the outside of the seat back  120 - 4 , as indicated with an arrow K 5 . 
         [0118]    In this manner, by discharging the air, sucked from the seat cushion  110 - 1  side, via the duct  5214 , into the space  5125  closed with the back cover  5124 , and blowing the air from the seat back  120 - 4  side, it is possible to simultaneously perform air sucking in the seat cushion  110 - 1  and air blowing in the seat back  120 - 4  only using one blower  5210  and one duct  5214 . 
         [0119]    Note that in the present example, the groove  5113  formed in the pad member  5112  on the seat cushion  110 - 1  side and the hole  5123  formed in the pad member  5122  on the seat back  120 - 4  side are the same as those described in the example 5 using  FIG. 14 . 
         [0120]    As described above, according to the present example, the back surface of the seat back  120 - 4  provided with the lumber mechanism part  5126  and the blower  5210  is tightly closed. Accordingly, a duct to blow air from the surface of the seat back  120 - 4  is unnecessary. It is possible to simultaneously perform air sucking in the seat cushion  110 - 1  and air blowing in the seat back  120 - 4  with a more simple structure using one blower  5210  and one duct  5214 . 
       Example 7 
       [0121]    In the example 5, the example where air blowing in the seat cushion  110 - 1  and air sucking in the seat back  120 - 4  are simultaneously performed has been described. In the example 6, the example where air sucking in the seat cushion  110 - 1  and air blowing in the seat back  120 - 4  are simultaneously performed has been described. In the present example, an example where simultaneous air blowing in the seat cushion  110 - 1  and air sucking in the seat back  120 - 4  or simultaneous air sucking in the seat cushion  110 - 1  and air blowing in the seat back  120 - 4  is selected by selecting the rotational direction of the blower will be described using  FIG. 16 . 
         [0122]    In the structure shown in  FIG. 16 , the constituent elements the same as those described in the example 5 and the example 6 have the same numerals. The blower  5220  is different from that in the examples 5 and 6. That is, in the examples 5 and 6, the sirocco fan is used as the blower  5210 . In the present example, an axial flow fan is used as the blower  5220 . When the axial flow fan is used as the blower, it is possible to change the rotational direction of the axial flow fan (reverse rotation) by selecting the polarity of voltage applied to the axial flow fan. This reverses air flow direction. 
         [0123]    In the structure shown in  FIG. 16 , as in the case described in the example 5, air sucking from the seat back  120 - 4  and air blowing from the seat cushion  110 - 1  are performed by forward-rotating the axial flow fan of the blower  5220 . 
         [0124]    On the other hand, as in the case described in the example 6, air sucking from the seat cushion  110 - 1  and air blowing from the seat back  120 - 4  are performed by reverse-rotating the axial flow fan of the blower  5220 . 
         [0125]    Note that in the present example, the groove  5113  formed in the pad member  5112  on the seat cushion  110 - 1  side and the hole  5123  formed in the pad member  5122  on the seat back  120 - 4  are the same as those described in the example 5 using  FIG. 14 . 
         [0126]    In this manner, as the axial flow fan is used as the blower  5220 , it is possible to change the direction of air blowing from the blower  5220  by selecting the polarity of voltage applied to the blower  5220 . With this configuration, it is possible to select air sucking or air blowing in the surfaces of the seat cushion  110 - 1  and the seat back  120 - 4  in the same structure. 
       Example 8 
       [0127]    In the examples 5 to 7, the structure where the blower is provided on the seat back  120 - 4  side has been described. In the present example, an example where the blower is installed on the seat cushion  110 - 1  side will be described. 
         [0128]      FIG. 17  shows the structure of the vehicular seat in the present example. In the present example, a blower  5230  is installed under the seat cushion  110 - 1 , an intake  5231  of the blower  5230  and a groove  5113  of the seat cushion  110 - 1  are connected with a duct  5322 . And space  5125 , surrounded with a pad member  5122  of the seat back  120 - 4  and the back cover  5124 , and the discharge side of the blower  5230  are connected with a duct  5233 . Note that as the blower  5230 , a sirocco fan is used. 
         [0129]    In this structure, when the blower  5230  is operated, as in the case of the example 6, it sucks air on the surface side of the seat cover  5111  from the breathable seat cover  5111  via the duct  5322  connected to the intake  5231  and the groove  5113  of the seat cushion  110 - 1 , as indicated with an arrow L 1 . 
         [0130]    The air sucked from the surface side of the seat cover  5111  passes through the duct  5322  as indicated with an arrow L 2 , then is sucked from the intake  5231  into the blower  5230  as indicated with an arrow L 3 , and is discharged in the space  5125  closed with the back cover  5124  as indicated with an arrow L 4 . 
         [0131]    In the space  5125  closed with the back cover  5124 , in which the air has been discharged with the blower  5230 , the air pressure is higher than the atmospheric pressure. As a result, the air is blown to the outside of the seat back  120 - 4  from the large number of holes  5123  formed in the pad member  5122 , via the breathable seat cover  5121  of the seat back  120 - 4 , as indicated with an arrow L 5 . 
         [0132]    In this manner, the air sucked from the seat cushion  110 - 1  side via the duct  5322  is blown via the duct  5233  in the space  5125  closed with back cover  5124 , and is blown from the seat back  120 - 4  side. It is possible to simultaneously perform air sucking in the seat cushion  110 - 1  and air blowing in the seat back  120 - 4  with only one blower  5230 . 
         [0133]    Note that in the present example, the groove  5133  formed in the pad member  5122  on the seat cushion  110 - 1  side and the hole  5123  formed in the pad member  5122  on the seat back  120 - 4  side are the same as those described in the example 5 using  FIG. 14 . 
         [0134]    As described above, according to the present example, as the duct is attached in the tightly closed space on the back of the seat back  120 - 4  and is connected to the blower  5230  installed under the seat cushion  110 - 1 , a duct to blow the air from the surface of the seat back  120 - 4  is unnecessary. It is possible to simultaneously perform air sucking in the seat cushion  110 - 1  and air blowing in the seat back  120 - 4  with a more simple structure using one blower  5230 . 
         [0135]    Note that in the structure shown in  FIG. 17 , by changing the attachment positions of the ducts  5322  and  5233  to the blower  5230 , as in the case described in the example 5, it is possible to suck air from the seat cover  5121  side of the seat back  120 - 4  into the space  5125  closed with the back cover  5124 , then send the air through the duct  5233  to the blower  5230 , then send the air from the blower  5230  via the duct  5322  to the seat cushion  110 - 1  side, and inject the air from the seat cover  5111  of the seat cushion  110 - 1 . 
         [0136]    Further, as the blower  5230 , by using an axial flow fan in place of the sirocco fan as in the case of the example 7, it is possible to change the direction of air sending from the blower  5230  by selecting the polarity of voltage applied to the blower  5230 , and to select air sucking or air blowing in the surfaces of the seat cushion  110 - 1  and the seat back  120 - 4  in the same structure. 
         [0137]    As described above, the invention made by the present inventor has been concretely described based on the examples. The present invention is not limited to the above-described examples, but it goes without saying that various changes can be made without departing from its subject matter. 
       REFERENCE SIGNS LIST 
       [0138]      100  . . . vehicular seat  110 ,  110 - 1  . . . seat cushion  111 ,  121  . . . seat cover  112 ,  122  . . . pad member  120 ,  120 - 1 ,  120 - 2 ,  120 - 3 ,  120 - 4  . . . seat back  140  . . . fan  141  . . . air duct  31  . . . seat-surface side skin member  32  . . . intermediate layer member  33  . . . pad side member  321  . . . recess  323  . . . hole  2121  . . . seat cover  2122  . . . pad member  2123 ,  2124  . . . hole  2210 ,  2220 ,  2230  . . . back cover  2211 ,  2221 ,  2231  . . . duct  2212 ,  222 ,  2232  . . . blower  2213  . . . lumber mechanism part  5112 ,  5122  . . . pad member  5113  . . . groove  5124  . . . back cover  5126  . . . lumber mechanism part  5210 ,  5220 ,  5230  . . . blower  5213 ,  5214 ,  5221 ,  5232 ,  5233  . . . duct.