BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a vehicle seat having an air conditioning function. 
   2. Description of the Related Art 
   Recently, there is known a vehicle seat having an air conditioning function in which a plurality of air holes are provided in a top cover member of a seat cushion and a seat back of the vehicle seat, and air from an air blower is ejected from the air holes (refer to JP-Tokukaihei-10-297274). 
   The vehicle seat disclosed in JP-Tokukaihei-10-297274 is schematically configured such that the plurality of air holes are provided to penetrate a top cover member, a cover pad and a pad forming the seat cushion and the seat back, an air blower, an intermediate duct and a seat cushion air exhaust duct are arranged on a lower surface of the seat cushion, and a seat back air exhaust duct is arranged on a back surface of the seat back. 
   A plurality of air outlets which slightly project from the surface to engage with the inside of the air holes are formed on the seat cushion air exhaust duct and the seat back air exhaust duct. The air from the air blower is fed to the seat cushion air exhaust duct and the seat back air exhaust duct through the intermediate duct, and is then ejected from the air holes connected to the air outlets to the seat surface. 
   However, in the vehicle seat disclosed in JP-Tokukaihei-10-297274, the structure is such that the outer diameter of each air outlet approximately equals to the inner diameter of the each air hole to thereby engage the air outlets with the air holes, so that, for example, when a passenger sits in the vehicle seat, and the seat cushion and the seat back are deformed by receiving the weight of the passenger, the air outlets slidably move in the air holes. Thus, when the amount of the deformation of the seat cushion and the like is large, the air outlets may be uncoupled from the air holes. 
   Moreover, in the vehicle seat disclosed in the Patent Document 1, the seat cushion air exhaust duct and the seat back air exhaust duct have an approximately plane shape corresponding to that the lower surface of the seat cushion and the back surface of the seat back are also have an approximately plane shape. 
   Accordingly, for example, when a passenger spills liquid such as a drink or the like, the liquid entered from the air holes may pass the inside of the air exhaust duct to reach the air blower, thereby damaging the air blower. 
   SUMMARY OF THE INVENTION 
   The present invention has been achieved in view of the above problem, and an object of the present invention is to provide a vehicle seat which comprises a seat air conditioning function capable of stably ejecting air. 
   To solve the above problem, in accordance with the first aspect of the present invention, the vehicle seat of the present invention comprises:
         a seat cushion and a seat back formed by covering a surface of a seat pad with a top cover member;   a plurality of air holes which penetrate the seat pad to reach a surface of the top cover member;   a plurality of air outlets which project from a surface of a duct to be connected to the air holes; and   an air blower to pressure and feed air inside a vehicle compartment to the air holes through the duct and the air outlets,   wherein an engagement portion which projects in a radial direction of one of the air outlets is provided at a tip of the one of the air outlets.       

   According to the vehicle seat, an engagement portion which projects in a radial direction of one of the air outlets is provided at a tip of the one of the air outlets. Thus, for example, the air outlets are fixed to the seat cushion and the seat back by sinking the engagement portions into the inner circumferential surfaces of the air holes in a state where the air outlets are inserted in the air holes. For example, even when a passenger sits in the vehicle seat, and the seat cushion and the seat back are deformed by receiving the weight of the passenger, the air outlets do not uncouple from the air holes, enabling to stably ejecting air. 
   Consequently, it is possible to obtain the vehicle seat which has a seat air conditioning function capable of ejecting comfortable air with high pressure, comfortable to sit in, and is further easy to be manufactured. 
   Preferably, in the vehicle seat of the present invention, the vehicle seat further comprises an insert member which has a tubular shape and is embedded inside one of the air holes,
         wherein one of the air outlets is inserted into the insert member to be engaged therewith.       

   According to the vehicle seat, since the insert member is used, the air outlets can be fixed to the seat cushion and the seat back more firmly. 
   Preferably, in the vehicle seat of the present invention, the insert member is integrally formed with the seat pad. 
   According to the vehicle seat, by integrally forming the insert member with the seat pad, embedding operation of the insert member to the inside of the air hole can be eliminated, enabling to simplify the manufacturing process of the vehicle seat. Moreover, the insert member can be fixed to the seat pad more firmly. 
   Preferably, in the vehicle seat of the present invention, the duct has a bellows structure at least at one position thereof. 
   According to the vehicle seat, providing the bellows structure in the duct can make it possible to deform the duct to flexibly correspond to the deformation of the seat cushion and the seat back, which makes the air outlet not easily uncoupled from the air hole. 
   In accordance with the second aspect of the present invention, the vehicle seat of the present invention comprises:
         a seat cushion and a seat back formed by covering a surface of a seat pad with a top cover member;   a plurality of air holes which penetrate the seat pad to reach a surface of the top cover member;   a plurality of air outlets which project from a surface of a duct to be connected to the air holes; and   an air blower to pressure and feed air inside a vehicle compartment to the air holes through the duct and the air outlets,   wherein a bellows structure is provided at two or more positions of the duct between continuing two of the air outlets.       

   For example, when the seat back is deformed by receiving the weight of a passenger at the time of sitting in the vehicle seat, the relative position of the two air outlets which are consecutively provided on the duct also changes. Because of the position change, the external force acts to each air outlet to uncouple the air outlets from the air holes. 
   As described above, in the case of providing two or more bellows structures between the two consecutive air outlets, the portion between the two bellows structures of the duct inclines and rotates corresponding to the relative position change of the two air outlets accompanying the deformation of the seat back. However, the portion between the air outlet and the bellows structure does not incline and rotate. That is, the relative position change of the two air outlets is absorbed at the portion between the two bellows structures, so that the action of the external force acting to the air outlets to uncouple the air outlets from the air holes can be decreased, thus enabling to obtain the effect to increase the bonding strength of the air outlet to the air hole. 
   Consequently, the vehicle seat having the air conditioning function capable of stably ejecting air can be obtained. 
   Preferably, in the vehicle seat of the present invention, an engagement portion is provided at a tip of one of the air outlets, the engagement portion projecting in a radial direction of the one of the air outlets. 
   According to the vehicle seat, an engagement portion which projects in a radial direction of one of the air outlets is provided at a tip of the one of the air outlets. Thus, for example, the air outlets are fixed to the seat cushion and the seat back by sinking the engagement portions into the inner circumferential surfaces of the air holes in a state where the air outlets are inserted in the air holes. For example, even when a passenger sits in the vehicle seat, and the seat cushion and the seat back are deformed by receiving the weight of the passenger, the air outlets do not uncouple from the air holes, enabling to stably ejecting air. 
   Preferably, in the vehicle seat of the present invention, the vehicle seat further comprises an insert member which has a tubular shape and is embedded inside one of the air holes,
         wherein one of the air outlets is inserted into the insert member to be engaged therewith.       

   According to the vehicle seat, since the insert member is used, the air outlets can be fixed to the seat cushion and the seat back more firmly. 
   Preferably, in the vehicle seat of the present invention, the insert member is integrally formed with the seat pad. 
   According to the vehicle seat, by integrally forming the insert member with the seat pad, embedding operation of the insert member to the inside of the air hole can be eliminated, enabling to simplify the manufacturing process of the vehicle seat. Moreover, the insert member can be fixed to the seat pad more firmly. 
   In accordance with the third aspect of the present invention, the vehicle seat of the present invention comprises:
         a seat cushion and a seat back formed by covering a surface of a seat pad with a top cover member;   a plurality of air holes which penetrate the seat pad to reach a surface of the top cover member;   a plurality of air outlets which project from a surface of a duct to be connected to the air holes; and   an air blower to pressure and feed air inside a vehicle compartment to the air holes through the duct and the air outlets,   wherein a portion of the duct attached to the seat cushion side and the seat back side bends upward or downward with respect to a horizontal direction.       

   According to the vehicle seat, since a portion of each duct attached to the seat cushion side and the seat back side bends upward or downward with respect to the horizontal direction. Thus, for example, when a passenger spills liquid such as a drink or the like on the seat cushion or the seat back, the liquid entered from the air holes into the ducts is prevented from flowing at the upwardly bending portion of the duct, or stays at the downwardly bending portion of the duct. Thus, the situation of the air blower failure due to the liquid reached to the air blowers can be prevented from occurring. 
   Consequently, the vehicle seat having the air conditioning function capable of stably ejecting air can be obtained. 


   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not intended as a definition of the limits of the present invention, and wherein; 
       FIG. 1  is a perspective view showing an outline of a vehicle seat; 
       FIG. 2  is a longitudinal sectional view of a main portion showing a structure of a seat cushion; 
       FIG. 3  is a cross sectional view of a main portion showing a coupling structure of an air hole and an air outlet; 
       FIG. 4  is a perspective view showing a framework structure of the seat cushion side of the vehicle seat; 
       FIG. 5  is a perspective view showing the framework structure of the seat cushion side of the vehicle seat; 
       FIG. 6  is a perspective view showing a framework structure of the seat back side of the vehicle seat; 
       FIG. 7  is a perspective view showing an outline of a vehicle seat; 
       FIG. 8  is a longitudinal sectional view of a main portion showing a structure of a seat cushion; 
       FIG. 9  is a cross sectional view of a main portion showing a coupling structure of an air hole and an air outlet; 
       FIG. 10  is a perspective view showing a framework structure of the seat cushion side of the vehicle seat; 
       FIG. 11  is a perspective view showing the framework structure of the seat cushion side of the vehicle seat; 
       FIG. 12  is a perspective view showing a framework structure of the seat back side of the vehicle seat; 
       FIG. 13  is a front view showing a structure of an intermediate duct; 
       FIGS. 14A and 14B  are bottom views showing structures of the intermediate duct; 
       FIG. 15  is a perspective view showing an outline of a vehicle seat; 
       FIG. 16  is a longitudinal sectional view of a main portion showing a structure of a seat cushion; 
       FIG. 17  is a perspective view showing a framework structure of the seat cushion side of the vehicle seat; 
       FIG. 18  is a perspective view showing the framework structure of the seat cushion side of the vehicle seat; 
       FIG. 19  is a front view showing a duct shape on the seat cushion side of the vehicle seat; 
       FIG. 20  is a perspective view showing a framework structure of the seat back side of the vehicle seat; and 
       FIG. 21  is a front view showing the duct shape on the seat back side of the vehicle seat. 
   


   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   First Embodiment 
   The first embodiment for embodying the present invention will be explained in detail below referring to the drawings. 
   As shown in  FIG. 1 , a vehicle seat  10  is schematically configured to comprise a seat cushion  20 , a seat back  30 , a head rest  40  provided on the upper portion of the seat back  30  and the like. Among them, as shown in  FIG. 2 , the seat back  30  is configured such that a surface of a pad  31  which keeps a seat shape and functions as a cushion member is covered with a cover pad  32  with permeability, and the surface of the cover pad  32  is further covered with a top cover member  33 .  FIG. 2  shows the seat back  30 , however, similarly, the seat cushion  20  is also configured such that the surface of the pad  31  is covered with the cover pad  32  and the top cover member  33 . Hereinafter, the combination of the pad  31  and the cover pad  32  is described as a “seat pad  34 ”. 
   As shown in  FIG. 1 , there are a plurality of air holes  33   a  formed in the surface of the top cover member  33 . As shown in  FIG. 3 , a tubular insert member  35  is embedded inside the air hole  33   a.    
   The insert member  35  is fixed to the inside of each air hole  33   a  by producing the seat pad  34  by foam molding in a state where the insert member  35  is arranged at the predetermined position in a seat pad molding die beforehand. 
     FIG. 4  is a perspective view showing a framework structure of the seat cushion  20  side of the vehicle seat  10 , and  FIG. 5  is a perspective view of the framework structure as seen from the lower surface side. 
   The framework structure of the seat cushion  20  side is schematically configured to comprise a pair of right and left seat rails  21 , a pair of right and left seat frames  22  attached to the seat rails  21 , seat springs  23 , a pan frame  24  which is crossed over the seat springs  23  and the front portions of the seat frames  22 , and the like. 
   As shown in  FIG. 5 , air blowers  50 A and  50 B for the seat cushion  20  are attached to the front and center of the lower surface of the pan frame  24 , respectively. 
   As shown in  FIG. 4 , a duct  60 A connected to the air blow hole of the front air blower  50 A passes the opening provided in the pan frame  24  to reach the upper surface of the pan frame  24 , and extends backward on the upper surface of the pan frame  24  in the state of branching off in right and left direction. 
   As shown in  FIGS. 4 and 5 , a duct  60 B connected to the air blow hole of the central (back) air blower  50 B extends backward on the lower surface side of the pan frame  24 , and branches off in right and left direction. 
   As shown in  FIG. 3 , a plurality of tubular air outlets  61 A,  61 B are provided to project upward at the positions on the upper surface of the ducts  60 A,  60 B corresponding to the plurality of air holes  33   a , respectively. Pawl shaped engagement portions  62 A,  62 B are formed at the tips of the air outlets  61 A,  61 B to project in a radial direction, respectively. 
     FIG. 6  is a back view of the seat back  30 , and the seat back  30  is schematically configured to comprise a sub seat frame  31  having an opening  31   a  in the center, a seat spring (omitted from the drawings) attached to the sub seat frame  31  and the like. 
   An air blower  50 C for the seat back is attached to one of the right and left lower sides of the back surface of the sub seat frame  31 . 
   A duct  60 C connected to the air blow hole of the air blower  50 C extends upward from the right and left positions in the opening  31   a  of the sub seat frame  31 . Each of the right and left ducts and the intermediate duct extending between the right and left ducts in the right and left direction has a bellows structure  70  at two points. 
   At the positions corresponding to the plurality of air holes  33   a  on the front surface of the duct  60 C, similar to the above seat cushion  20  side, a plurality of tubular air outlets  61 C are provided to project upward. A pawl shaped engagement portion  62 C is formed at the tip of each air outlet  61 C to project in a radial direction. 
   As shown in  FIG. 3 , the air outlets  61 A,  61 B,  61 C of the seat cushion  20  side and the seat back  30  side are all designed to have a length slightly longer than the length of the insert member  35  in an axis direction. Each of the engagement portions  62 A,  62 B,  62 C of the air outlets  61 A,  61 B,  61 C is inserted into the insert member  35  to engage the tip portion of the insert member  35 , so that each of the air outlets  61 A,  61 B,  61 C is fixed to the insert member  35 , and consequently, fixed to the seat cushion  20  or the seat back  30 . 
   As above, according to the seat vehicle  10  of this embodiment, the air outlets  61 A,  61 B,  61 C projecting from the ducts  60 A,  60 B,  60 C engage the insert members  35  embedded inside the air holes  33   a  through the engagement portions  62 A,  62 B,  62 C, respectively, so that, for example, even when a passenger sits in the vehicle seat  10 , and the seat cushion  20  and the seat back  30  are deformed by receiving the weight of the passenger, the air outlets  61 A,  61 B,  61 C do not uncouple from the air holes  33   a , enabling to stably ejecting air. 
   Providing the bellows structures  70  in the duct  60 C on the seat back side can make it possible to deform the duct  60 C to flexibly correspond to the deformation of the seat back  30 , which makes the air outlet  61 C not easily uncoupled from the air hole  33   a.    
   Only one bellows structure  70  may be provided between the consecutive two air outlets  61 C in the right and left direction and the vertical direction, respectively, however, as shown in  FIG. 6 , it is preferable to provide two or more bellows structures between two air outlets  61 C. In the case where two or more bellows structures exist between two air outlets  61 C, even when an external force acts on the air outlets  61 C with the deformation of the seat back  30 , and the relative position of the two air outlets  61 C is changed, only the portion of the duct  60 C between the two bellows structures  70  inclines or the like to absorb this position change. Thus, it is possible to further make the air outlets  61 C not easily uncoupled from the air holes  33   a.    
   The bellows structure  70  may be provided on the ducts  60 A,  60 B on the seat cushion  20  side. In this case, similar to the bellows structure  70  provided on the seat back  30  side, it is possible to make the air outlets  61 A,  61 B not easily uncoupled from the air holes  33   a.    
   In this embodiment, the insert member  35  is embedded inside each air hole  33   a , and each of the engagement portions  62 A,  62 B,  62 C of the air outlets  61 A,  61 B,  61 C engages the insert member  35 , however, it is not limited thereto. The structure may be such that the air outlets  61 A,  61 B,  61 C are fixed to the seat cushion  20  and the seat back  30  by sinking the pawl shaped engagement portions  62 A,  62 B,  62 C into the inner circumferential surfaces of the air holes  33   a  in a state where the air outlets  61 A,  61 B,  61 C are inserted in the air holes  33   a  without providing the insert member  35  to the inside of each air hole  33   a.    
   Second Embodiment 
   The second embodiment for embodying the present invention will be explained in detail below referring to the drawings. 
   As shown in  FIG. 7 , a vehicle seat  110  is schematically configured to comprise a seat cushion  120 , a seat back  130 , a head rest  140  provided on the upper portion of the seat back  130  and the like. Among them, as shown in  FIG. 8 , the seat back  130  is configured such that a surface of a pad  131  which keeps a seat shape and functions as a cushion member is covered with a cover pad  132  with permeability, and the surface of the cover pad  132  is further covered with a top cover member  133 . FIG.  8  shows the seat back  130 , however, similarly, the seat cushion  120  is also configured such that the surface of the pad  131  is covered with the cover pad  132  and the top cover member  133 . Hereinafter, the combination of the pad  131  and the cover pad  132  is described as a “seat pad  134 ”. 
   As shown in  FIG. 7 , there are a plurality of air holes  133   a  formed in the surface of the top cover member  133 . As shown in  FIG. 9 , a tubular insert member  135  is embedded inside the air hole  133   a.    
   The insert member  135  is fixed to the inside of each air hole  133   a  by producing the seat pad  134  by foam molding in a state where the insert member  135  is arranged at the predetermined position in a seat pad molding die beforehand. 
     FIG. 10  is a perspective view showing a framework structure of the seat cushion  120  side of the vehicle seat  110 , and  FIG. 11  is a perspective view of the framework structure as seen from the lower surface side. 
   The framework structure of the seat cushion  120  side is schematically configured to comprise a pair of right and left seat rails  121 , a pair of right and left seat frames  122  attached to the seat rails  121 , seat springs  123 , a pan frame  124  which is crossed over the seat springs  123  and the front portions of the seat frames  122 , and the like. 
   As shown in  FIG. 11 , air blowers  150 A and  150 B for the seat cushion  120  are attached to the front and center of the lower surface of the pan frame  124 , respectively. 
   A duct  160 A connected to the air blow hole of the front air blower  150 A passes the opening provided in the pan frame  124  to reach the upper surface of the pan frame  124  as shown in  FIG. 10 , and extends backward on the upper surface of the pan frame  124  in the state of branching off in right and left direction. 
   As shown in  FIGS. 10 and 11 , a duct  160 B connected to the air blow hole of the central (back) air blower  150 B extends backward on the lower surface side of the pan frame  124 , and branches into right and left direction. 
   As shown in  FIG. 9 , a plurality of tubular air outlets  161 A,  161 B are provided to project upward at the positions on the upper surface of the ducts  160 A,  160 B corresponding to the plurality of air holes  133   a , respectively. Pawl shaped engagement portions  162 A,  162 B are formed at the tips of the air outlets  161 A,  161 B to project in a radial direction, respectively. 
     FIG. 12  is a back view of the seat back  130 , and the seat back  130  is schematically configured to comprise a sub seat frame  131  having an opening  131   a  in the center, a seat spring (omitted from the drawings) attached to the sub seat frame  131  and the like. 
   An air blower  150 C for the seat back is attached to one of the right and left lower sides of the back surface of the sub seat frame  131 . 
   A duct  160 C connected to the air blow hole of the air blower  150 C extends upward from the right and left positions in the opening  131   a  of the sub seat frame  131 . In the following explanation, the ducts  160 C extending upward from the right and left positions are represented as “left side duct  160 Ca” and “right side duct  160 Cb”, respectively, and the duct  160 C extending in right and left direction between the left side duct  160 Ca and the right side duct  160 Cb is represented as “central duct  160 Cc”. 
   On each of the left side duct  160 Ca and the right side duct  160 Cb, a plurality of (three in  FIG. 12 ) tubular air outlets  161 C (first air outlets  161 Ca,  161 Cd, second air outlets  161 Cb,  161 Ce and third air outlets  161 Cc,  161 Cf) are formed. Also, two bellows structures  170  are provided between the first air outlet  161 Ca and the second air outlet  161 Cb, and between the first air outlet  161 Cd and the second air outlet  161 Ce, respectively. Further, two bellows structures  170  are provided between the two right and left third air outlets  161 Cc,  161 Cf. 
   The operation of the bellows structure  170  will be explained below referring to the two bellows structures  170  provided on the central duct  160 Cc. 
     FIG. 13  is a front view of the central duct  160 Cc, and  FIGS. 14A and 14B  are bottom views of the central duct  160 Cc. 
   For example, when a passenger sit in the vehicle seat  110  and the seat back  130  is deformed by receiving the weight of the passenger, the relative position of the third air outlets  161 Cc,  161 Cf consecutively provided in the central duct  160 Cc in the right and left direction changes relative to the back and forth direction, and each of the right and left bellows structures  170  bends and extends corresponding thereto. Thereby, only a portion  160 Cc′ between the two bellows structures  170  of the central duct  160 Cc inclines, and a portion  160 Cc″ between the third air outlet  161 Cc and the left side bellows structure  170  does not incline, maintaining the condition same as the condition before the relative position change of the third air outlets  161 Cc,  161 Cf. Thus, the relative position change of the third air outlets  161 Cc,  161 Cf is absorbed by the portion  160 Cc′ between the two bellows structures  170  of the central duct  160 Cc, so that action of the external force to the third air outlets  161 Cc,  161 Cf to uncouple the third air outlets  161 Cc,  161 Cf from the air holes  133   a  can be decreased, thus enabling to obtain the effect to increase the bonding strength of the air outlet  161 C to the air hole  133   a.    
   The effect similar to the above effect can be obtained when the relative position of the third air outlets  161 Cc,  161 Cf changes relative to the up and down direction, and also on the left side duct  160 Ca and the right side duct  160 Cb by the bending and extension of the two bellows structures  170  provided on each duct. 
   Further, the above described two bellows structures  170  may be provided on the ducts  160 A,  160 B on the seat cushion  120  side. In this case, similar to the two bellows structures  170  provided on the seat back  130  side, it is possible to make the air outlets  161 A,  161 B not easily uncoupled from the air holes  133   a.    
   As shown in  FIG. 9 , the engagement portions  162 A,  162 B,  162 C projecting in the radial direction are formed at the tips of the air outlets  161 A,  161 B,  161 C, respectively. The air outlets  161 A,  161 B,  161 C of the seat cushion  120  side and the seat back  130  side are all designed to have a length slightly longer than the length of the insert member  135  in the axis direction. Each of the engagement portions  162 A,  162 B,  162 C of the air outlets  161 A,  161 B,  161 C is inserted into the insert member  135  to engage the tip portion of the insert member  135 , so that each of the air outlets  161 A,  161 B,  161 C is fixed to the insert member  135 , and consequently, fixed to the seat cushion  120  or the seat back  130 . 
   As above, according to the vehicle seat  110  of this embodiment, for example, even when a passenger sits in the vehicle seat  110 , and the seat cushion  120  and the seat back  130  are deformed by receiving the weight of the passenger, the two bellows structures  170  provided between two consecutive air outlets  161 A,  161 B,  161 C is bent and extended. Thus, as described above, the effect of increasing the bonding strength of the air outlets  161 A,  161 B,  161 C to the air holes  133   a  can be obtained. Further, the air outlets  161 A,  161 B,  161 C projecting from the ducts  160 A,  160 B,  160 C engage the insert members  135  embedded inside the air holes  133   a  through the engagement portions  162 A,  162 B,  162 C, respectively, so that the air outlets  161 A,  161 B,  161 C do not uncouple from the air holes  133   a . Thus, the effect to further increase the bonding strength of the air outlets  161 A,  161 B,  161 C to the air holes  133   a  can be obtained, enabling to stably eject air. 
   In this embodiment, the insert member  135  is embedded inside each air hole  133   a , and each of the engagement portions  162 A,  162 B,  162 C of the air outlets  161 A,  161 B,  161 C engages the insert member  135 , however, it is not limited thereto. The structure may be such that the air outlets  161 A,  161 B,  161 C are fixed to the seat cushion  120  and the seat back  130  by sinking the pawl shaped engagement portions  162 A,  162 B,  162 C into the inner circumferential surfaces of the air holes  133   a  in a state where the air outlets  161 A,  161 B,  161 C are inserted in the air holes  33   a  without providing the insert member  135  to the inside of each air hole  133   a.    
   Third Embodiment 
   The third embodiment for embodying the present invention will be explained in detail below referring to the drawings. 
   As shown in  FIG. 15 , a vehicle seat  210  is schematically configured to comprise a seat cushion  220 , a seat back  230 , a head rest  240  provided on the upper portion of the seat back  230  and the like. Among them, as shown in  FIG. 16 , the seat back  230  is configured such that a surface of a pad  231  which keeps a seat shape and functions as a cushion member is covered with a cover pad  232  with permeability, and the surface of the cover pad  232  is further covered with a top cover member  233 .  FIG. 16  shows the seat back  230 , however, similarly, the seat cushion  220  is also configured such that the surface of the pad  231  is covered with the cover pad  232  and the top cover member  233 . Hereinafter, the combination of the pad  231  and the cover pad  232  is described as a “seat pad  234 ”. 
   There is a plurality of air holes  233   a  formed in the surface of the top cover member  233 , and as shown in  FIG. 16 , each air hole  233   a  is connected to the air outlet  261 C on the surface of the duct  260 C. As shown in  FIG. 16 , a tubular insert member  235  is embedded inside each of the plurality of air holes  233   a . 
     FIG. 17  is a perspective view showing a framework structure of the seat cushion  220  side of the vehicle seat  210 , and  FIG. 18  is a perspective view of the framework structure as seen from the lower surface side. 
   The framework structure of the seat cushion  220  side is schematically configured to comprise a pair of right and left seat rails  221 , a pair of right and left seat frames  222  attached to the seat rails  121 , seat springs  223 , a pan frame  224  which is crossed over the seat springs  223  and the front portions of the seat frames  222 , and the like. 
   As shown in  FIG. 18 , air blowers  250 A and  250 B for the seat cushion  220  are attached to the front and center of the lower surface of the pan frame  224 , respectively. 
   A duct  260 A connected to the air blow hole of the front air blower  250 A passes the opening provided in the pan frame  224  to reach the upper surface of the pan frame  224  and branches off in right and left direction. Also, as shown in  FIG. 19 , the duct  260 A is provided with a bending portion  270 A bending in the upper side with respect to the horizontal direction at a portion thereof, and the duct  260 A extends backward on the upper surface of the pan frame  224  from the bending portion  270 A. 
   A duct  260 B connected to the air blow hole of the central (back) air blower  250 B extends backward on the lower surface side of the pan frame  224 , and branches into right and left direction. Also, as shown in  FIG. 18 , the duct  260 B is provided with a bending portion  270 B bending in the lower side with respect to the horizontal direction at a portion thereof. 
   A plurality of tubular air outlets  261 A,  261 B are provided to project upward at the positions on the upper surface of the ducts  260 A,  260 B corresponding to the plurality of air holes  133   a , respectively. 
     FIG. 20  is a back view of the seat back  230 , and the seat back  230  is schematically configured to comprise a sub seat frame  231  having an opening  231   a  in the center, a seat spring (omitted from the drawings) attached to the sub seat frame  231  and the like. 
   An air blower  250 C for the seat back is attached to one of the right and left lower sides of the back surface of the sub seat frame  231 . 
   As shown in  FIG. 21 , a duct  260 C connected to the air blow hole of the air blower  250 C is provided with the bending portion  270  bending in the upper side with respect to the horizontal direction, and extends upward from the right and left two positions in the opening  231   a  of the sub seat frame  31 . 
   At the positions corresponding to the plurality of air holes  233   a  on the front surface of the duct  260 C, similar to the above seat cushion  220  side, a plurality of tubular air outlets  261 C are provided to project upward. 
   The air outlets  261 A,  261 B,  261 C of the seat cushion  220  side and the seat back  230  side engage the insides of the air holes  233   a  of the seat cushion  220  side and the seat back  230  side, respectively. 
   As above, according to the vehicle seat  210  of the embodiment, a portion of each of the ducts  260 A,  260 C in the state of being attached to the front of the seat cushion  220  side and the seat back  230  side bends upward with respect to the horizontal direction, so that, for example, when a passenger spills liquid such as a drink or the like on the seat cushion  220  or the seat back  230 , the liquid entered from the air holes  233   a  into the ducts  260 A,  260 C is prevented from flowing at the bending portions  270 A,  270 C at which the ducts  260 A,  260 C are bent upward. Thus, the situation of the air blower failure due to the liquid reached to the air blowers  250 A,  250 B can be prevented from occurring. 
   Moreover, according to the vehicle seat  210  of the embodiment, a portion of the duct  260 B in the state of being attached to the center (back) of the seat cushion  220  side bends downward with respect to the horizontal direction, so that, for example, when a passenger spills liquid such as a drink or the like on the seat cushion  220  or the seat back  230 , the liquid entered from the air holes  233   a  into the duct  260 B stays in the bending portion  270 B at which the duct  260 B is bent downward. Thus, the situation of the air blower failure due to the liquid reached to the air blower  250 B can be prevented from occurring. 
   The present invention is not limited to the above embodiments, and various improvements and design changes may be made without departing from the scope of the invention. 
   As above, the vehicle seat according to the present invention is useful as a seat mounted on the vehicle such as an automobile or the like, especially, the vehicle seat is suitable as a seat to give comfortable feeling to a passenger when the passenger sit in. 
   The entire disclosure of Japanese Patent Application Nos. Tokugan 2004-102527 which was filed on Mar. 31, 2004, Tokugan 2004-102594 which was filed on Mar. 31, 2004, Tokugan 2004-102601 which was filed on Mar. 31, 2004, Tokugan 2004-102620 which was filed on Mar. 31, 2004, and Tokugan 2004-102639 which was filed on Mar. 31, 2004, including specification, claims, drawings and summary are incorporated herein by reference in its entirety.
A vehicle seat having: a seat cushion and a seat back formed by covering a surface of a seat pad with a top cover member; a plurality of air holes which penetrate the seat pad to reach a surface of the top cover member; a plurality of air outlets which project from a surface of a duct to be connected to the air holes; and an air blower to pressure and feed air inside a vehicle compartment to the air holes through the duct and the air outlets, wherein an engagement portion which projects in a radial direction of one of the air outlets is provided at a tip of the one of the air outlets.