Patent Publication Number: US-2012024210-A1

Title: Tufted carpet

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to tufted carpet for use as floor carpet for a vehicle, for example, and includes pile yarns implanted in a base fabric using a tufting machine. 
     Typically, tufted carpets are formed using a tufting machine. In a tufted carpet, pile yarns extend along a stitch direction of a base fabric with respect to the base fabric. A plurality of rows of pile yarns are arranged along the gauge direction of the base fabric. 
     The applicant of the present invention has proposed a tufted carpet as described in Japanese Laid-Open Patent Publication No. 2000-239959. The tufted carpet includes pile yarns extending in a stitch direction of a base fabric with respect to the base fabric. A plurality of rows of pile yarns are arranged along a gauge direction of the base fabric. Each of the pile yarn rows is formed by tufting yarn material in a zigzag manner. In this type of tufted carpet, the lines of pile yarns extend loosely in the stitch direction. This improves the appearance of the product. 
     The tufted carpet may include both a visible portion and a non-visible portion on its outer surface when in use. For example, a floor carpet for a vehicle has both a visible portion and a non-visible portion as viewed from passengers who enter the passenger compartment of the vehicle. In this case, pile yarns are implanted into the visible portion with sufficient density to ensure a desirable appearance for the floor carpet, thus improving the texture of the floor carpet. In contrast, it is desirable to reduce the pile yarns in the non-visible portion in order to decrease the weight of the floor carpet. 
     In the tufted carpet described in the aforementioned document, yarn streaks of the yarns along the stitch direction are weakened, thus improving the appearance of the carpet. However, since the carpet as a whole is formed in a uniform manner, a visible portion and a non-visible portion as viewed from passengers when in use have equal densities for the pile yarns. As a result, the tufted carpet cannot bring out new advantages caused by the density configuration of the pile yarns. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an objective of the present invention to provide a dense tufted carpet that has improved texture and desirable appearance and is simply configured with reduced weight. 
     To achieve the foregoing objective and in accordance with one aspect of the present invention, a tufted carpet is provided that includes pile yarns implanted into a base fabric, a high density portion, and a low density portion. The high density portion has the pile yarns implanted into the base fabric with a high density. The low density portion has the pile yarns implanted into the base fabric with a low density. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing a tufted carpet according to one embodiment of the present invention; 
         FIG. 2A  is a schematic view showing a tufted carpet having pile yarns implanted into the tufted carpet with both high density and low density; 
         FIG. 2B  is a schematic view showing a tufted carpet having pile yarns implanted with uniform density; and 
         FIG. 3  is a view schematically illustrating the manufacture of a tufted carpet using a tufting machine. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     One embodiment of a tufted carpet according to the present invention will now be described with reference to  FIGS. 1 to 3 . 
     As illustrated in  FIG. 1 , a tufted carpet  10  is formed like a sheet having a rectangular shape as viewed from above. The tufted carpet  10  has a high density portion  13  and a low density portion  14 . Pile yarns  12  are implanted with high density in a portion of the base fabric  11  corresponding to the high density portion  13 . Pile yarns  12  are implanted with low density in the portion of the base fabric  11  corresponding to the low density portion  14 . As illustrated in  FIGS. 2A and 2B , the tufted carpet  10  is formed by implanting the pile yarns  12  into the base fabric  11  using a tufting machine. The base fabric  11  is formed of polyester or the like. The pile yarns  12  are formed of nylon (polyamide), polyester, polypropylene or the like. The size of the pile yarns  12  is 900 to 1500 dtex. 
     In the tufted carpet  10 , it is preferable that the fiber density of the high density portion  13 , which is the mass of the pile yarns  12 , be set to a value in the range of 280 to 700 g/m 2 . It is also preferable that the fiber density of the low density portion  14  be set to a value in the range of 200 to 500 g/m 2 . The fiber density of the high density portion  13  is set to a value greater than the fiber density of the low density portion  14 . 
     A fiber density of the high density portion  13  less than 280 g/m 2  deteriorates the texture and appearance of the tufted carpet  10  and lowers the quality of the tufted carpet  10 . A fiber density of the high density portion  13  exceeding 700 g/m 2  causes non-uniform implanting of the pile yarns  12  and lowers productivity of the tufted carpet  10 . Such fiber density is thus not preferable. A fiber density of the low density portion  14  less than 200 g/m 2  causes an insufficient implantation amount of the pile yarns  12  and lowers the quality of the tufted carpet  10 . Such fiber density is thus not preferable. A fiber density of the low density portion  14  exceeding 500 g/m 2  is excessively great, so that the low density portion  14  no longer has low density. 
     With reference to  FIG. 2A , the stitch (ST 1 ) of the high density portion  13  is set to a value greater than the stitch (ST 2 ) of the low density portion  14 . A stitch (ST) represents the number of the implanted pile yarns  12  per inch. Specifically, it is preferred that the stitch of the high density portion  13  be set to a value in the range of 8.0 to 17.0 and that the stitch of the low density portion  14  be set to a value in the range of 6.0 to 12.0. The stitch of the high density portion  13  is set to a value greater than the stitch of the low density portion  14 . 
     A stitch of the high density portion  13  less than 8.0 cannot achieve the advantages of being a high density portion  13 . Specifically, the texture and appearance of the tufted carpet  10  are deteriorated. A stitch of the high density portion  13  exceeding 17.0 causes non-uniform implanting of the pile yarns  12 , lowers the production rate for the tufted carpet  10 , and is thus not preferable. A stitch of the low density portion  14  less than 6.0 is excessively small and lowers the quality of the tufted carpet  10 , which is not preferable. A stitch of the low density portion  14  exceeding 12.0 is excessively great so that the low density portion  14  no longer has low density. 
     The length (PH) of the pile yarns  12  is set as needed in correspondence with use or purpose of the tufted carpet  10 . The gauge (G) is fixed by the base of the tufting machine and normally cannot be changed. The gauge (G) represents the density of the pile yarns  12  in a lateral direction of the tufted carpet  10 . A non-illustrated second base fabric or a felt or a film is bonded to the backside of the tufted carpet  10  when necessary. 
     It is preferable to set the difference between the fiber density of the high density portion  13  and the fiber density of the low density portion  14  to a value in the range of 30 to 250 g/m 2 . If such difference is less than 30 g/m 2 , the advantages of providing the high density portion  13  and the low density portion  14  in the tufted carpet  10  become less significant, and reduction of the weight the tufted carpet  10  becomes insufficient. In contrast, when the difference between the fiber densities exceeds 250 g/m 2 , the high density portion  13  includes an excessively great amount of pile yarns  12  and the low density portion  14  has an insufficient amount of pile yarns  12 . This deteriorates the quality of the tufted carpet  10 . 
     An apparatus and a method for manufacturing the tufted carpet  10  will hereafter be described. 
     As illustrated in  FIG. 3 , the facility for manufacturing the tufted carpet  10  includes a tufting machine  15 , a base fabric roller  16 , a pile yarn feeder (a creel)  17 , a plurality of guide rollers  18 , and a winding roller  19 . The tufting machine  15  implants the pile yarns  12  in the base fabric  11 . The base fabric  11  is wound around the base fabric roller  16 . The pile yarn feeder  17  feeds pile yarns (yarn material). The winding roller  19  winds the tufted carpet  10 . The tufting machine  15  receives the base fabric  11  from the base fabric roller  16  and the pile yarns  12  from the pile yarn feeder  17 . The tufting machine  15  implants the pile yarns  12  in the base fabric  11  by means of needles in the stitch direction and the gauge direction. 
     The tufting machine  15  moves the base fabric  11  slowly when forming the high density portion  13 , compared to when forming the low density portion  14 . This forms the high density portion  13  in the tufted carpet  10 . In other words, the implantation amount of the pile yarns  12  is increased by maintaining the speed constant at which the needles implant the pile yarns  12  and reducing the speed at which the base fabric  11  is moved. As a result, the above-described high density portion  13  is formed. 
     The operation of a machine for producing the tufted carpet  10  will hereafter be described. 
     To manufacture the tufted carpet  10  having the high density portion  13  and the low density portion  14  as illustrated in  FIG. 3 , the tufting machine  15  operates in the manner described below. Specifically, the feeding speed of the base fabric  11  output by the base fabric roller  16  is decreased when the high density portion  13  is being formed, compared to the feeding speed of the base fabric  11  at the time when the low density portion  14  is being formed. In other words, when the tufting machine  15  is forming the low density portion  14 , the feeding speed of the base fabric  11  slows down as the pile yarns  12  are implanted continuously in the base fabric  11 . In this manner, in the procedure for manufacturing the tufted carpet  10 , the high density portion  13  is formed subsequent to the low density portion  14 . 
     The tufted carpet  10 , which is obtained in the above-described manner, has the high density portion  13  having pile yarns  12  implanted with high density and the low density portion  14  having pile yarns  12  implanted with low density. As a result, the pile yarns  12  implanted with the high density ensure denseness, improved texture, and desirable appearance of the high density portion  13 . In contrast, the pile yarns  12  implanted with the low density decreases the weight and ensures simple configuration of the low density portion  14 . The tufted carpet  10  may be used as, for example, a floor carpet for a vehicle. Specifically, the tufted carpet  10  is used with the high density portion  13  arranged at a position to be visible and the low density portion  14  arranged at a position to be visible. 
     More specifically, as represented by Table 1, the gauge (G) was set to 1/10 in Examples 1, 2, and 3. In other words, the gauge (G) was set in such a manner that ten pile yarns  12  existed per inch. Then, the tufted carpet  10  was manufactured by setting the stitch (ST 1 ) of the high density portion  13 , the stitch (ST 2 ) of the low density portion  14 , the height (PH) of each pile yarn  12 , and the fiber density as represented in Table 1. As a result, by increasing the density of the pile yarns  12 , improved texture and desirable appearance were obtained in the high density portion  13 . In contrast, by decreasing the density of the pile yarns  12 , simple configuration and weight reduction were ensured in the low density portion  14 . 
     
       
         
           
               
               
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                   
                 ST 
                 PH 
                 Fiber Density 
               
               
                   
                 G 
                 (Piles/Inch) 
                 (mm) 
                 (g/m 2 ) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 Example 1 
                  1/10 
                 ST1 12.5 
                 5.5 
                 360 
               
               
                   
                   
                  1/10 
                 ST2 9.4 
                 5.5 
                 285 
               
               
                   
                 Example 2 
                  1/10 
                 ST1 14.8 
                 6.0 
                 450 
               
               
                   
                   
                  1/10 
                 ST2 8.1 
                 6.0 
                 270 
               
               
                   
                 Example 3 
                  1/10 
                 ST1 14.1 
                 5.5 
                 400 
               
               
                   
                   
                  1/10 
                 ST2 8.0 
                 5.5 
                 250 
               
               
                   
                   
               
            
           
         
       
     
     The illustrated embodiment has the advantages described below. 
     (1) The tufted carpet  10  has the high density portion  13  and the low density portion  14 . The high density portion  13  has an improved texture and a desirable appearance ensured by the pile yarns  12  implanted with a high density. In contrast, the low density portion  14  is reduced in weight by the pile yarns  12  implanted with a low density. This configuration provides a tufted carpet  10  that is dense, improved in texture and appearance, expensive looking, simply configured, and light-weight. 
     (2) The fiber density of the high density portion  13  is in the range of 280 to 700 g/m 2 . The fiber density of the low density portion  14  is in the range of 200 to 500 g/m 2 . The fiber density of the high density portion  13  is set to a value greater than the fiber density of the low density portion  14 . This ensures a sufficiently great difference between the fiber density of the high density portion  13  and the fiber density of the low density portion  14 . As a result, the above-described advantages are brought about by the high density portion  13  and the low density portion  14 . 
     (3) The stitch of the high density portion  13  is in the range of 8.0 to 17.0. The stitch of the low density portion  14  is in the range of 6.0 to 12.0. The stitch of the high density portion  13  is a value greater than the stitch of the low density portion  14 . In this configuration, the stitch of the high density portion  13  and the stitch of the low density portion  14  are both adequate. As a result, the respective advantages of the high density portion  13  and the low density portion  14  are each ensured. Also, the pile yarns  12  are smoothly implanted into the base fabric  11 . 
     (4) The difference between the fiber density of the high density portion  13  and the fiber density of the low density portion  14  is set to a value in the range of 30 to 250 g/m 2 . This ensures a clear difference in fiber density between the high density portion  13  and the low density portion  14 . As a result, the respective advantages of the high density portion  13  and the low density portion  14  are each brought about effectively. 
     (5) The high density portion  13  is formed in the tufted carpet  10  by reducing the movement speed of the base fabric  11  in the tufting machine  15  compared to the feeding speed of the base fabric  11  at the time when the low density portion  14  is being formed. In other words, the high density portion  13  is easily formed simply by changing the feeding speed of the base fabric  11 . 
     The above described embodiment may be modified as follows. 
     A single tufted carpet  10  may include a plurality of high density portions  13  and a plurality of low density portions  14 . In this case, the sizes of the high density portions  13  and the sizes of the low density portions  14  may be changed as needed in correspondence with the intended purpose. 
     The fiber densities or the stitches of the high density portion  13  and the low density portion  14  may be set as needed in correspondence with the size or the length of each pile yarn  12 . 
     A middle density portion may be arranged between the high density portion  13  and the low density portion  14 . Specifically, the middle density portion has a density between the density of the pile yarns  12  forming the high density portion  13  and the density of the pile yarns  12  forming the low density portion  14 .