Patent Publication Number: US-2009220760-A1

Title: Ventilation material

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATION 
     This patent application is a continuation-in-part (CIP) application of U.S. patent application Ser. No. 11/708,514 filed Feb. 20, 2007, for “Ventilation Material” that application is deemed entirely incorporated by reference herein for any purpose. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The invention relates to ventilation materials and more particularly to a three-layer sheet-like article having an improved ventilation structure formed therein as a material for manufacturing sheet of cloth, mat, footwear, mattress cover, or the like. 
     2. Description of Related Art 
     Footwear, protective devices for athletes, mats, or mattress covers typically have a ventilation material formed therein for bringing a feeling of comfort to a person wearing same or lying or sitting thereon. A sheet of article having a conventional ventilation material formed therein is shown in  FIGS. 7 ,  8  and  9 . The sheet of article comprises a lower layer of knitted fabric  30  formed of a water-impermeable and water vapor-permeable fabric, an upper layer of knitted fabric  32  formed of a water-impermeable and water vapor-permeable fabric, and an intermediate layer of ventilation material  31  formed between the upper and lower layers  32  and  30 . The layer of ventilation material  31  comprises a plurality of longitudinal apertures  311  arranged in parallel rows as air ducts. 
     It is designed to cause the sheet of article to have a ventilation effect. However, in fact, it is not true. In detail, the apertures  311  are too small to conduct sufficient air flow through the layers  30 ,  31 , and  32 . Further, the heat absorbing area of the layer of ventilation material  31  is relatively large. Thus, for example, a person wearing a pair of shoes having the layer of ventilation material  31  formed therein may feel a degree of discomfort and coldness. Furthermore, the layer of ventilation material  31  is an integral pad having the same stiffness in every portion. Thus, it is impossible of producing an article (e.g., a protective device for athlete) requiring some enhanced portions as protection by means of the well known ventilation material  31 . Thus, the need for improvement still exists. 
     SUMMARY OF THE INVENTION 
     It is therefore one object of the invention to provide a ventilation structure, comprising a lower layer of knitted fabric formed of a water-impermeable and water vapor-permeable fabric; an upper layer of knitted fabric formed of a water-impermeable and water vapor-permeable fabric; a plurality of first support members uniformly distributed formed between the upper and the lower layers, each first support member having a first hardness, each first support member having a polygonal first top surface and a polygonal first bottom surface; a plurality of second support members uniformly distributed formed between the upper and the lower layers, each second support member having a second hardness, the second hardness being higher than the first hardness, each second support member having a polygonal second top surface and a polygonal second bottom surface; and a plurality of reticulated air ducts formed between the upper and the lower layers with the support members disposed thereamong. 
     In one aspect of the invention the first support members and the second support members are shaped as triangle. Each first support member has a triangular first top surface and a triangular first bottom surface. Each second support member has a triangular second top surface and a triangular second bottom surface. 
     In another aspect of the invention the first support members and the second support members are shaped as hexagon. Each first support member has a hexagonal first top surface and a hexagonal first bottom surface. Each second support member has a hexagonal second top surface and a hexagonal second bottom surface. 
     In a further aspect of the invention the first support members and the second support members are formed of plastic. 
     In a yet further aspect of the invention the first support members and the second support members both have at least one projecting portion contacting either the upper layer or the lower layer. 
     The above and other objects, features and advantages of the invention will become apparent from the following detailed description taken with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         FIG. 1  is a perspective view of a sheet of article incorporating a preferred embodiment of ventilation material according to the invention; 
         FIG. 2  is a partially broken away view of  FIG. 1 ; 
         FIG. 3  is a longitudinal sectional view of an enlarged portion of  FIG. 1 ; 
         FIG. 4  is a partially broken away view of another preferred embodiment of ventilation material; 
         FIG. 5  is a perspective view of a sheet of article incorporating a preferred embodiment of ventilation material; 
         FIG. 6  is a side view of a sheet of article incorporating a preferred embodiment of ventilation material when in use; 
         FIG. 7  is a perspective view of a sheet of article having a conventional ventilation material formed therein; 
         FIG. 8  is an exploded view of  FIG. 7 ; and 
         FIG. 9  is a longitudinal sectional view of an enlarged portion of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     Referring to  FIGS. 1 to 6 , a sheet of article incorporating a preferred embodiment of ventilation material according to the invention is shown. The sheet of article comprises a lower layer of knitted fabric  10  formed of a water-impermeable and water vapor-permeable fabric, an upper layer of knitted fabric  12  formed of a water-impermeable and water vapor-permeable fabric, and a plurality of first support members  11  uniformly distributed formed between the upper and the lower layers  12  and  10 . Each first support member  11  has a first hardness and each first support member  11  has a polygonal first top surface and a polygonal first bottom surface, and a plurality of second support members  13  uniformly distributed formed between the upper and the lower layers  12  and  10 . Each second support member  13  has a second hardness and the second hardness is higher than the first hardness. Each second support member  13  has a polygonal second top surface and a polygonal second bottom surface. Preferably, the first support members  11  and the second support members  13  are formed of plastic. Further, shape of the first support members  11  and the second support members  13  other than triangle and hexagon is contemplated by the invention. In addition, stiffness of the first support members  11  may be different from that of the second support members  13  depending on applications. For example, stiffness enhancement of some portions of a protective device for athlete made of the sheet of article is desired. As shown in  FIG. 2 , one side of the first support member  11  of one row is parallel with one side of another first support member  11  of an adjacent row. Note that the orientation of the first support members  11  other than above is also contemplated by the invention. 
     Preferably, the first support members  11  and the second support members  13  are shaped as triangle. Each first support member  11  has a triangular first top surface and a triangular first bottom surface. Each second support member  13  has a triangular second top surface and a triangular second bottom surface. 
     Preferably, the first support members  11  and the second support members  13  are shaped as hexagon. Each first support member  11  has a hexagonal first top surface and a hexagonal first bottom surface, each second support member  13  has a hexagonal second top surface and a hexagonal second bottom surface. 
     Preferably, the first support members  11  and the second support members  13  both have at least one projecting portion  111  contacting either the upper layer  12  or the lower layer  10 . 
     Referring to  FIG. 2 , the ventilation material of the present invention utilizes foamed plastic materials, in the manufacture process, to create the geometric support members  11  and  13 . First, a sheet of foamed plastic is subjected to a cutting machine that cuts the foamed plastic material to a desired thickness. Second, once the foamed plastic material is prepared to the desired thickness, a second cutting tool cuts the foamed plastic, in a cookie cutter fashion, to create support members  11  and  13  of the desired geometric shape. Third, the excess material present between the cut geometric shapes is removed leaving individual geometric support members  11  and  13 . Finally, as seen in  FIG. 2 , the individual geometric support members  11  and  13  are adhered to the upper surface of the lower layer  10  and the lower surface of the upper layer  12 . The disclosed configuration creating a sandwich configuration with the support members  11  and  13  disposed between the upper and lower layers  12  and  10 . The adhesives appropriate for such applications are well known in the art. The materials employed to create the upper layer  12  and the lower layer  10 . 
     The present invention utilizes different raw materials and different foamed plastics to form the support members  11  and  13  of different hardness, such as PE (Polyethylene), EVA (Ethylene Vinyl Acetate Copolyn) or TPE (Thermoplastic elastomer rubber). According to the different needs, the support members  11  and  13  have different hardness. For example, a number of the second support members  13  designed to protect is harder than another number of the first support members  11 . Moreover, the present invention shows better deformation and fits well to the body of the user owing to the plurality of the support members  11  and  13 . 
     Referring to  FIG. 3  specifically, a plurality of air ducts  14  are formed between the layers  10  and  12 . Also, the air ducts  14  are reticulated with the support members  11  and  13  disposed among them. Advantageously, a total space occupied by the air ducts  14  is sufficiently large. Thus, the desired ventilation effect can be achieved by conducting air flow through the lower layer  10 , the air ducts  14 , and the upper layer  12 . Hence, for example, a person wearing a pair of shoes having the intermediate Support members  11  formed therein may feel a degree of comfort. Additionally, padding material such as foam can be placed in some air ducts  14  for increasing the shock absorbing capability of the sheet of article without adversely affecting the ventilation effect. 
     In one application, a mat incorporating the support members  11  and  13  with thus formed air ducts  14  can be placed on a sheet of cloth. Thereafter, person(s) may sit on the mat. Advantageously, the mat can bring a degree of comfort to the person(s) sitting thereon. 
     Alternatively, the first support members  11  and the second support members  13  have a projecting portion  111  and  131  contacting either the upper layer  12  or the lower layer  10  such that a massaging effect to the corresponding body portion is carried out when a person sits on, for example, a mat having the support members  11  and  13  formed therein. 
     The support members  11  and  13  have different hardness. Additionally, the rigidity of some support members  11  are different from that of the remaining support members  13  depending on applications. For example, rigidity enhancement may be appropriate for some portions of a protective device for athletics. The air ducts  14  are reticulated with the supporting members  11  and  13  disposed among them. 
     While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims.