Abstract:
The present invention is direct to angular border on three dimensional sheet material and method of producing. This invention is producing an attractive and finely finished article.

Description:
FIELD OF INVENTION 
     This present invention relates to a plastic sheet three-dimensional receptacle or the like provided with a uniform border, and includes the method of manufacturing, thereby producing an attractive and finely finished article. 
     BACKGROUND OF INVENTION 
     A plastic sheet three-dimensional receptacle is known. 
     Plastic sheets, picture frames, and picnic plates have long been produced such as illustrated in U.S. Pat. Nos. 5,876,143; 5,059,052; 5,752,721; 5,417,509; 6,254,707. 
     Paper materials are less likely to be used today because they are easily torn or deformed requiring disposal. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is an object of this invention to provide a plastic three-dimensional sheet. 
     Another object of this invention is to provide an inexpensive device easy to manufacture. 
     Still further object of this invention is to provide an attractive product. 
     A still further object of this invention is to provide a three dimensional article which can be stacked and packaged. 
     Yet another object of this invention is to provide a method for manufacturing a three dimensional article. 
    
    
     In summary this invention pertains to the manufacture of sheet material with an angular border and the method of manufacturing the same as will be described in the following description and the drawings which are as follows; 
     FIG. 1 is a schematic showing the manufacturing process; 
     FIG. 2 is a top elevation view showing a three dimensional picture frame; 
     FIG. 3 is a cross-sectional view enlarged taken along the lines  3 — 3  of FIG.  2  and viewed in the direction of the arrows; 
     FIG. 4 is an enlarged fragmentary top planned view of a corner of the invention shown in FIG. 2; 
     FIG. 5 is a top plan view showing an article being inserted into the three-dimensional invention illustrated in FIG. 2; 
     FIG. 6 is a modified version of the invention shown in top plan; 
     FIG. 7 is a cross-sectional view taken along the line  7 — 7  of FIG.  6  and viewed in the direction of the arrows; 
     FIG. 8 is a fragmentary top plan view of the invention; 
     FIG. 9 is a enlarged fragmentary cross-sectional view showing the cutter and weld member for producing the marginal edge of the item shown in FIG. 8; 
     FIG. 10 is a fragmentary perspective view of the cutter shown in FIG. 9; and 
     FIG. 11 is a fragmentary perspective view of the inner border shown in FIG.  8 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The FIG. 1 shows the system S set up to manufacture a picture frame. The system S includes a bottom roll of material  2  and a top roll of material  4 . The material  2  is generally an opaque thermoplastic material of a thickness of from about 215 to about 245 microns or about 7½ to 11½ gauge. A top roll  4  is a thermal plastic material having a thickness of from about 170 to about 210 microns and a gauge of about 6½ to 8½. The preferred thickness of the material on roll  2  is about 230 microns or about 9 gauge. The preferred thickness for the top roll of thermoplastic material  4  is about 190 microns or about 7 gauge. The preferred plastic is polypropylene although other thermal plastic materials may be used such as acrylics for example. 
     The material on the roll  2  comes off of the roll  2  as a web sheet  6 . The material from the roll  4  comes off as a web sheet  8 . The sheets  6  and  8  come together at idler rolls  10  and  12 . Web sheet  8  prior to entering the idler rolls  10  and  12  may be slit at one edge by a cutter  14  engaging a backup roll  16 . The webs  6  and  8  form a 2-ply web  20  which is fed to a die stamping unit  22  having a platen beneath it  24 . The unit  22  with the platen  24  simultaneously produce welds and cuts by the use of ultrasound in the manner shown in U.S. Pat. No. 6,254,707 granted Jul. 3, 2001 and as subsequently illustrated and described in FIGS. 8 through 11 of this description. 
     The 2-ply web  20  is fed to a stripper unit having an upper member  26  and a lower member  28 . The stripper unit A causes the frame F best shown in FIGS. 2 through 5 to be released from the 2-ply web  20  and deposited on the conveyor  30  with the excess material  32  from the web  20  to be deposited on a collecting roll  34 . 
     It will now be noted in FIGS. 2 through 5 that the frame F has a border  36 , which runs around the central portion  38  comprised of the 2-ply  40  and  42  in the central portion as well as 2-ply  44  and  46  in the border as best shown in FIG.  3 . It is to be noted that the plys  40  and  42  are co-extensive but not secured to each other except at the marginal edge weld  48  and the inner border welds  50 ,  52 ,  54  and  56 . Diagonal welds  58 ,  60 ,  62 , and  64  are provided which extend from the corners  66 ,  68 ,  70 , and  72 . The diagonal  58 ,  60 ,  62 , and  64  do not touch the edge weld  48  which extends around the perimeter of the frame F. Diagonal welds  58 ,  60 ,  62 , and  64  are spaced from about ⅛ to about ⅝ of an inch from the corners  66 ,  68 ,  70 , and  72 . The welds  50 ,  52 ,  54  and  56  comprise a series of welds which do not touch each other and are spaced from each other from about ⅛ to about ⅝ of an inch. Diagonal welds  58 ,  60 ,  62  and  64  do not touch the welds  50 ,  52 ,  54 , and  56  and are spaced therefrom about ⅛ to about ⅝ of an inch. Preferably the spacing is approximately ½ inch between the diagonal welds  58 ,  60 ,  62 , and  64  and the corners  66 ,  68 ,  70 ,  72  and the border welds  50 ,  52 ,  54 , and  56 . 
     The frame F has an opening  74  which is caused when the cutter  14  slits the web sheet  8  on one side thereof. The opening  74  permits insertion of a picture, paper or the like P into the opening  74  which forms a pocket in the central member  38  for display of the picture or other material which is inserted therein. 
     It will now be noted that the frame F at the border  36  is uplifted at an angle from the plain of the central member  38  at an angle from about 3 degrees to an elevation of about 15 degrees. 
     FIGS. 6 and 7 
     FIGS. 6 and 7 show a plate or dish-like construction D. In this construction, a single sheet of material is used coming from the bottom roll  2  without utilizing the upper roll  4  and is dye-stamped at  22  and  24  and stripped at stripper A and deposited on the conveyor  30  with the excess material  32  being picked on the collecting roll  34 . The edge welds  76  and the border welds  78 ,  80 ,  82 ,  84 , and the diagonal welds  86 ,  88 ,  90 , and  92  all are stamped into the plate D. 
     FIGS. 8 through 11 
     The welds discussed in the earlier description are all based on FIGS. 8 through 11 and the U.S. Pat. No. 6,254,707. FIG. 9 shows the edge cutter  94  which cuts through the 2-ply  20  which is stripped from the article such as the frame F or the plate D. The castellated dyes C include the cutter  94  and the castellations  96 . The castellations  96  form the spaced apart indentation  98  and  100  on the border with the edge cut  102 . The inner diagonal welds  104  and the border welds  106  are formed by the dye H having the castellations  108 . The dye H does not have a cutter  94  as does the castellated dye C. As in the aforementioned U.S. Pat. No. 6,254,707 ultrasound produces a vibration which produces sufficient heat and causes the bonding and welding of the plastic material. This affords an attractive frame F or plate D or other device of three dimensions. It is obvious that other configurations or devices not rectangular such as triangular or the like may be utilized by this process. The castelation aspect causes the deflection of the borders upwardly and depending upon the depth of the castellations and the length of time of the ultrasound at the point of contact with the sheet material, a deflection may be increased for example from about 3 degrees to about 15 degrees as desired which may also be determined by the delay in which the dyes are held before release. The depth of castelllation is from about 60% to about 80% of the thickness of the plastic sheet material.