Vehicle seat

Abstract

A vehicle seat is composed of: a base member 40 elastically connected to and supported on any of frame members arranged separately in a width direction of a seat frame, through metal springs 41, to constitute a lower layer; a first net member 50 of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, stretched above the base member 40 and between the frame members arranged separately in the width direction, to constitute a middle layer; and a second net member 60 of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, disposed to cover the top of the middle layer and stretched with a tension lower than that of the first net member constituting the middle layer, to constitute an upper layer.

What is claimed is:  
     
         1 . A vehicle seat, comprising: 
 a base member elastically connected to and supported on any of frame members arranged separately in a width direction of a seat frame, through metal springs, to constitute a lower layer;    a first net member of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, stretched above said base member and between the frame members arranged separately in the width direction, to constitute a middle layer; and    a second net member of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, disposed to cover the top of said middle layer and stretched with a tension lower than that of said first net member constituting said middle layer, to constitute an upper layer.    
     
     
         2 . The vehicle seat according to  claim 1 , wherein said base member is located between frame members constituting a seat cushion part which are arranged separately in the width direction of the seat frame, and said metal spring runs between each frame member and each side portion of said base member.  
     
     
         3 . The vehicle seat according to  claim 2 , wherein said base member is further elastically supported hung through a metal spring engaged with any of frame members constituting a seat back part of the seat frame.  
     
     
         4 . The vehicle seat according to any one of claims  1 , wherein said base member is connected to means for preventing bounce upward.  
     
     
         5 . The vehicle seat according to any one of claims  1 , wherein said base member is a substantially flat-type elastic member.  
     
     
         6 . The vehicle seat according to  claim 5 , wherein the substantially flat-type elastic member constituting said base member is a net member of a three-dimensional structure in which a front mesh layer and a back mesh layer are connected by a large number of piles.  
     
     
         7 . The vehicle seat according to any one of claims  1 , wherein said first net member constituting said middle layer is stretched in loop form between the frame members arranged separately in the width direction.  
     
     
         8 . The vehicle seat according to  claim 1 , wherein a viscoelastic member is inserted between a part of said first net member constituting said middle layer covering the frame member and said second net member constituting said upper layer, or between said first net member constituting said middle layer and the frame member around which said first net member is wound.  
     
     
         9 . The vehicle seat according to  claim 8 , wherein said viscoelastic member is formed into a structure having a plurality of divided block parts with one or more boundary parts, which are processed thin in thickness, intervening therebetween.  
     
     
         10 . The vehicle seat according to  claim 8 , wherein said viscoelastic member is formed including viscoelastic polyurethane, or is formed including a net member of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, formed into a structure having a plurality of divided block parts with one or more boundary parts, which are processed thin in thickness, intervening therebetween.  
     
     
         11 . The vehicle seat according to  claim 8 , wherein said viscoelastic member is formed including a net member of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, formed into a structure having a plurality of divided block parts with one or more boundary parts, which are processed thin in thickness, intervening therebetween, and viscoelastic polyurethane which is integrally joined to one face of the net member of a three-dimensional structure.  
     
     
         12 . The vehicle seat according to  claim 8 , wherein said viscoelastic member is formed including a net member of a three-dimensional structure, in which a front mesh layer and a back mesh layer are connected by a large number of piles, formed into a structure having a plurality of divided block parts with one or more boundary parts, which are processed thin in thickness, intervening therebetween, and an elastic base member to either face of which the net member of a three-dimensional structure is integrally joined.  
     
     
         13 . The vehicle seat according to any one of  claims 1  to  12 , wherein a viscoelastic member which is connected to and supported on any of the frame members forming the seat frame is further disposed at one or both of a front edge portion of the seat cushion part and a lumbar supporting part and below said second net member forming said upper layer.  
     
     
         14 . The vehicle seat according to  claim 13 , wherein only one end of said viscoelastic member disposed on the front edge portion of the seat cushion part is connected to and supported on any of the frame members disposed at the front end of the seat frame for the seat cushion part.