Patent Abstract:
An embossed surface is positioned opposite a pile fabric from a tip shearing apparatus. As the blades of the tip shearing apparatus contact the carpet, the embossed surface selectively elevates selected portions of carpet relative to unselected portions so that a design corresponding to the design of the embossed surface is inversely cut into the carpet.

Full Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a method and apparatus for finishing textile products, and more particularly, to a method and apparatus for tip shearing tufted carpet utilizing an embossed surface below the backing which extends portions of the carpet closer to the cutting heads thereby cutting a pattern into the carpet which inversely corresponds with the extended portions of the embossed surface.  
         [0003]     2. Brief Description of Related Art  
         [0004]     One method of finishing tufted carpet is to tip shear the loop ends to a uniform height. U.S. Pat. No. 4,323,612, which issued in 1982, discusses carpets finished in this manner.  
         [0005]     The traditional method of tip shearing carpets involves running tufted carpet over a smooth roller where the roller contacts the polypropylene backing on the bottom of the carpet. The tufted loops are then cut to a uniform height utilizing a cutter having one or more blades which cuts the tufted loops to a uniform height relative to the back of the polypropylene layer on the back of a carpet since the blades of the cutter are a fixed distance from the roller. The greater a distance the tips of the pile extend from the backing, the greater amount is sheared.  
         [0006]     The tip-shearing of carpet is utilized to provide a visual effect since the sheared ends provide a different visual effect than non-sheared ends. It has been discovered that the more material which is sheared away (i.e., the shorter lengths the carpet tufts are cut to extend from the backing), the darker most carpets become. It has also been discovered that loops are more durable and take wear better than sheared loops.  
         [0007]     In some applications, it has been found that carpet may be tufted to high and low loops with the high loops resembling a design. The high loops may then be tip sheared to create a different effect than if they were allowed to remain as loops with the low loops not being cut in this process. While this technique produces an attractive carpet design, the sheared high loops extend a distance above the non-sheared low loops. Accordingly the sheared high loops take the brunt of the wear. Accordingly a need exists for a pattern to be cut into a carpet where the cut pattern extends a distance below the remaining loops.  
         [0008]     U.S. Pat. No. 6,035,749 discloses a method of patterned shearing of pile fabrics which effectively utilizes compressed air to provide a particular pattern when utilized in conjunction with an otherwise uniform cutting and severing apparatus. While this reference teaches an excellent way of producing patterns in pile fabrics, it requires the addition of compressed air and jets to be placed proximate to the cutter assembly. This would require retrofitting existing tip shearing cutters with compressed air capability, jets and a controller for the jets.  
         [0009]     Accordingly, a need exists to produce a design in carpets without necessarily requiring retrofilling and/or providing compressed air capability.  
       SUMMARY OF THE INVENTION  
       [0010]     A need exists to be able to utilize existing tip shearing cutter equipment with a simple modification and/or addition to provide a patterned visual effect in the top surface of a pile fabric so that the finish fabric has a plurality of heights as measured from the back of the polypropylene backing.  
         [0011]     Another need exists for tip-shearing carpet to provide a visual effect which is recessed relative to surrounding carpet portions.  
         [0012]     Another need exists for selectively tip shearing carpet to at least two depths utilizing an otherwise uniform cutting shearing apparatus.  
         [0013]     Another need exists to selectively elevate portions of pile fabric relative of non-selected portions to assist in providing a desired multi-height pattern when the elevated carpet portions contact the cutting blade or blades.  
         [0014]     Accordingly, an embossed surface is positioned below the backing of the carpet during the shearing process. The embossed surface has raised portions which elevate portions of the carpet closer to the cutter of the tip shearing machine. These elevated portions are cut to a deeper depth than surrounding carpet portions. Accordingly, the cut pattern is inversely cut in the pile fabric relative to the embossed surface. This technique and apparatus is believed to result in a longer wearing carpet product. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which:  
         [0016]      FIG. 1  shows a prior art tip shearing apparatus;  
         [0017]      FIG. 2  shows a first embodiment of a tip shearing apparatus of the present invention;  
         [0018]      FIG. 3  shows a carpet section produced using the tip shearing apparatus of  FIG. 2 ;  
         [0019]      FIG. 4  shows a cross section of carpet taken along the line A-A of  FIG. 3 ; and  
         [0020]      FIG. 5  shows a side elevational view of an alternatively preferred embodiment for an embossed surface for use with the cutter of  FIG. 2 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]     Accordingly,  FIG. 1  shows a portion of a prior art tip shearing mill  10  having a cutter  12  and a smooth roller  14 . As carpet  16  is passed intermediate the cutter  12  and the roller  14 , the tips  16 , or ends, are sheared to a uniform height as measured from the smooth cylindrical exterior surface  17  of the roller  14 . As shown in  FIG. 1 , a high pile  18  height has been tufted to create a cross pattern which extends a distance above the lower pile  20 . After shearing, the high pile loops will be cut, but preferably not down as far as the top of the low pile  20 . This is known in the art to create a pattern. However, a disadvantage of this process is that the sheared or cut pile design (formerly high pile  20 ) is not as durable as the lower loops. Thus some designs have been found to wear disproportionately faster than the rest of the carpet since they bear the traffic as they extend a distance above the lower pile height.  
         [0022]      FIG. 2  shows a tip shearing mill  30  of the preferred embodiment. The mill includes a shearing apparatus, such as a cutter  32 , and an embossed surface  34  on a roller  36 . The embossed surface  34  is shown attached to the roller  36  and having three distinct designs  38 , 40 , 42 , but as shown in and described relative to  FIG. 5 , other embossed surfaces may be utilized with or without a roller  36 . Furthermore, the one or more designs  38 , 40 , 42  are illustrative in nature and could have any particular shape desired utilized using the technology described herein. As shown in  FIG. 2 , the designs  38 , 40 , 42  have elevated surfaces  39 , 41 , 43  spaced a distance above unelevated roller surface  45 .  
         [0023]      FIG. 3  shows a carpet section  44  which has been run through the mill  30 . Notice that the design of the embossed surface  34  is now apparent on the carpet  44 . However, as shown in  FIG. 4 , the designs  38 , 40 , 42  have been cut into the carpet  44 . For instance, suppose that the carpet  44  is formed of a uniform pile height. As reflected by  FIG. 4 , as the carpet  44  passes over the embossed surface  34 , the portions which now have the design are elevated a greater distance, i.e., moved closer to the cutter  32 , so that the blade, or blades, of the cutter  32  cut more material from the carpet where the embossed surface  34  pushes the carpet closer to the cutter  32 , even though the cutter  32  is cutting at a uniform height relative to the roller  36 . This results in the embossed surface  34  effectively being cut into the carpet  44  as shown in  FIG. 4 . In fact, the depth of recessions  47 , 48 , 49  approximately corresponds with the height of the elevated surfaces  39 , 41 , 43  relative to the unelevated surface  45 .  
         [0024]     Embossed surfaces  34  for may take a variety of forms. As shown in  FIG. 2 , a roller  36  may be machined or otherwise constructed so that designs  38 , 40 , 42 , or other ornamentation extend a distance above an adjacent exterior and otherwise smooth cylindrical portion of the roller such as unelevated roller surface  45 . The designs  38 , 42  may perpendicularly extend a predetermined distance from the unelevated surface  45  and/or extend a variety of distances gradually as shown by design  40 .  
         [0025]     Embossed surfaces  34  may be created on a roller  36  as illustrated in  FIG. 2  or may be created in sheet form as shown in  FIG. 5 .  FIG. 5  shows a continuous loop  50  having an embossed surface  34  thereon which could be utilized with the cutter  32  of  FIG. 2 . Alternatively a sheet segment  52  such as shown intermediate B-B and C-C in  FIG. 5  may be fed along with carpet across the smooth roller  14  shown in  FIG. 1  or other structure to achieve the desired pattern. The sheet  50  need not be continuous as illustrated, but the continuous sheet  50  is believed to be a convenient structure to utilize, especially for a repeating pattern.  
         [0026]     A method of utilizing the apparatus, or mill  30 , involves directing carpet  44  intermediate the embossed surface  34  and the cutter  32 , having the cutter cut at a uniform height and thereby produce a design in the carpet  44 , or other pile fabric, inversely corresponding to the design of the embossed surface.  
         [0027]     As shown in  FIG. 2 , at least one of the embossed surface  34  and or cutter  32  is moveable relative to the other so that the desired amount of cutting may take place. Some carpets may have longer pile height than others, some may have thicker backing, and the ability to adjust the predetermined distance from the cutter to the embossed surface and/or roller, if utilized, is believed to be advantageous.  
         [0028]     Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to the preferred embodiment of the invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Technology Classification (CPC): 3