Abstract:
A novel dog chew is disclosed made of raw hide which has a large plurality of closely spaced perforations cut there through during manufacture of the dog chew. Typically the perforations are created in first rows that are generally parallel to each other and in second rows that are also generally parallel to each other, and the first rows intersect the second rows to create a cross hatching pattern. The intersecting sets of perforations created by the cross hatch pattern define a large number of small sections on the rawhide. The small sections of the dog chew individually break off when chewed by a dog instead of large pieces that may choke the dog.

Description:
FIELD OF THE INVENTION 
     The present invention relates to products that are chewed and eaten by animals, such as dogs, and are made of animal skin or a synthetic material. 
     BACKGROUND OF THE INVENTION 
     A product made for dogs generally called “chews” are given to dogs for a variety of reasons. Chews are used to occupy a dog and to help clean its teeth. 
     Chews can be made from a variety of materials. For example, they are often made of processed, dried animal skin, such as rawhide (untanned) cattle skin, buffalo skin or pigskin. The skin is processed by removing hair and cleaning it. The skin can also be treated to soften it, if desired. The skin is then formed into a desired final shape for distribution, such as by folding or rolling if necessary, and then dried. In the shaping process smaller filler pieces may be added. The final product may be a flat chip, a roll, or look like a bone. 
     In the prior art, dog chews are made of materials other than rawhide. For example, the chews can be made of man made shoe fiber, other man made composite materials and cellulose. 
     In the chewing process a dog may chew off pieces that are too large and they sometimes attempt to swallow the pieces. The dog will choke on the larger pieces. 
     Thus, there is a need in the prior art for a dog chew that inhibits pieces being chewed off that are too large and cause a dog to choke when they attempt to swallow the pieces. 
     SUMMARY OF THE INVENTION 
     The need in the prior art for an improved dog chew is satisfied by the present invention. The base material from which the dog chew is made has a large number of relatively closely spaced perforations cut through it. These perforations are formed through the base material, usually a sheet of rawhide from which the dog chew is made, prior to the material being rolled or otherwise formed into the final shape of a dog chew. The perforations are created in a plurality of first rows that are generally parallel to each other and in a plurality of second rows that are also generally parallel to each other, and the first rows intersect the second rows to create a cross hatching. The plurality of first and second rows may be perpendicular to each other. The perforations create a large plurality of small rawhide sections that will individually break off in lieu of large pieces that may choke a dog. 
     While animal skins may be utilized to make a dog chew, many other materials may also be utilized. Any chewable base material that is safe for a dog to chew may be utilized. Such other materials include man made shoe fiber, cellulose, and other man made composite materials. 
     The rawhide is first soaked and treated, then the perforations are cut through the base material used to make a dog chew, and finally the perforated raw hide is rolled or otherwise formed into its final shape. Such final shapes are typically a bone, a rod or a flat piece called a “chip”. When the dog chew is a bone shape the rawhide forming the middle area between bulbous ends of the bone may or may not be perforated. Not perforating the middle area help prevent the bulbous ends from breaking off. 
     The large plurality of small sections that are created by the intersecting pattern of perforations facilitate the small pieces defined by the small sections breaking off into small pieces when the rawhide product is chewed by a dog. In addition, the pieces that break off are small enough as not to choke the dog when the pieces are swallowed. 
     The design of the smaller sections created by the perforations can vary in shape or size. The size of the perforations and the distance between the perforations in any direction can be varied depending on how easily it is desired to make the sections break off rawhide when it is chewed, and to set the size of the pieces that break off. 
     The perforations are each elongated penetrate through the sheet base material from which dog chews are formed. The perforations are preferably one-quarter inch long and spaced one-quarter inch apart in any direction. The perforations through the base material are created using a special tool. The tool may be in the form of a flat bed press having a large plurality of small blades that form the cross hatching perforation pattern, or the tool may be a pair of rollers on which is a plurality of small cutter blades for forming the cross hatching perforation pattern when the base material is passed between the rollers. Other techniques may also be utilized to create the perforations. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The invention will be better understood upon reading the following Detailed Description in conjunction with the drawings in which: 
         FIG. 1  shows a piece of material with a large plurality of perforations there through that are somewhat randomly located; 
         FIG. 2  shows a piece of material with a large plurality of perforations there through that are exactly located in rows and columns; 
         FIG. 3  shows a piece of perforated material that has been cut to a final shape with a large plurality of perforations there through that are exactly located in rows and columns; 
         FIG. 4  shows the perforated material of  FIG. 3  rolled into a chew rod; 
         FIG. 5  shows a perforated material formed into a bone shaped chew where the middle area of the bone chew is not perforated; 
         FIG. 6  shows how a flat piece of material is perforated before being shaped into a bone shaped chew where the middle area of the bone chew is not perforated; 
         FIG. 7  shows a variation of the bone shaped chew where the middle area of the bone chew is perforated and is made from a piece of material such as shown in  FIG. 3 ; 
         FIG. 8  shows a flat array of small cutting blades used to perforate a material in one direction; and 
         FIG. 9  shows a roller arrangement having small cutting blades thereon for perforating a sheet of material in two directions as the material passes between the rollers. 
     
    
    
     DETAILED DESCRIPTION 
     The need in the prior art for an improved dog chew is satisfied by the present invention. The base material from which the dog chew is made has a large number of closely spaced perforations. These perforations are typically cut through the base material, which is preferably a sheet of raw hide, after the raw hide is soaked and treated to enhance flexibility etcetera. The base material is then formed into the final shape of the dog chew and is dried. The perforations are created in first rows that are generally parallel to each other and in second rows that are generally parallel to each other, and the first rows of perforations intersect the second rows of perforations to create a cross hatching. The cross hatching creates a large plurality of small sections that make it easy for small pieces to break off rather than large pieces when a dog gnaws on the dog chew. 
     As briefly mentioned in the Summary of Invention many types of base materials can be perforated prior to being shaped into a dog chew. The base material is preferably an animal skin from any animal (rawhide), but it may be man made shoe fiber, cellulose, and other man made composite materials. In the following description only the term rawhide is used for the sake of simplicity and because it is the preferred material from which to make dog chews according to the teaching of the present invention. 
     Very briefly, as mentioned hereinabove, rawhide (untanned cattle skin, buffalo skin or pig skin) is preferably used to make a dog chew in accordance with the teaching of the present invention. The animal skin is first processed to remove hair and to clean it. The rawhide may then be treated to soften it somewhat. Next the rawhide is perforated in accordance with the teaching of the invention. Finally, the perforated rawhide is formed into the desired final shape, such as by folding or rolling, and it is dried. The cleaning and treatment of the rawhide is well known in the art and is not described herein. In addition, in the following description of the Figures the treatment of the rawhide is mentioned very little in order not to detract from the description of the invention. 
     In  FIG. 1  is shown an oval piece of rawhide  11  that has had a plurality of perforations  12 ,  13  cut there through. The shape of raw hide  11  need not be oval and this shape is used only for simplicity of presentation. Perforations  12  are formed in a direction that is different than perforations  13  and preferably are approximately perpendicular to each other, as shown. Each perforation  12  or  13  is a linear slit through the rawhide, and slits  12  and  13  are shown in rows that are not parallel to each other. However, the slits  12  and  13  need not be linear and they need not be in rows as shown. In  FIG. 1  the perforations  12  and  13  have been cut at different times in a two step process and the pattern of the cuts will typically be somewhat random as shown in  FIG. 1 . In addition, perforations  12  and  13  in  FIG. 1  may not be as close to perpendicular to each other as is preferred. Perforations  12  and  13  have been cut using a simple, two pass, flat bed cutter that is shown in and described hereinafter with reference to  FIG. 8 . 
     In  FIG. 2  is also shown another oval piece of rawhide  11  that has had a plurality of perforations  12 ,  13  cut there through. However, these perforations are very orderly in size, spacing and orientation. These perforations  12  and  13  have been concurrently cut using a rotary cutter that is shown in and described hereinafter with reference to  FIG. 9 . As also described hereinafter the orderly perforations may also be cut using a modified flatbed cutter. 
     After perforations are cut through a piece of rawhide  11 , such as shown in  FIGS. 1 and 2 , the raw hide is typically cut into a final shape before being formed into a dog chew and dried. One example of such a final shape is the rectangle piece shown in  FIG. 3 . The rectangular piece of perforated rawhide  61  shown in  FIG. 3  may be formed into a final shape such as the dog chew roll shown in  FIG. 4 . 
     In  FIG. 4  is shown a dog chew  17  that has been formed into the shape of a roll starting with a rectangular piece of perforated rawhide  16  such as shown in  FIG. 3 . The treatment of the rawhide, cutting of perforations, and cutting of pieces from a larger rawhide piece  11  are described elsewhere herein. The main difference is the finally shaping of the perforated rawhide  16  into the chew roll  17 . The shaping is done in a manner known in the art so is not described herein. 
     In  FIG. 5  is shown a dog chew that has been formed into the shape of a bone. The shaping is done in a manner known in the art so is not described herein. The treatment of the rawhide, cutting of perforations, and cutting of pieces from a larger rawhide  11  are as described elsewhere herein. The main difference is that no perforations are cut in the rawhide in the middle area  18  of the bone chew. This helps prevent bulbous ends  19  and  20  of the bone chew from breaking off from middle area  18  as the bone chew is being gnawed by a dog, and particularly by a larger dog. 
     In  FIG. 6  is shown how a flat piece of rawhide  16  is perforated before being shaped into the bone shaped chew shown in  FIG. 5 . A flat piece of already treated rawhide  16  has only its end areas  27  and  28  perforated and its middle area  26  is not perforated. Area  27  corresponds to end  19  of the bone chew in  FIG. 5 , area  28  corresponds to end  20  of the bone chew, and middle area  26  corresponds to the middle section  18  of the bone chew. By not having perforations in the middle area  27  of rawhide  16  the structural integrity of the middle section  18  of the bone chew is increased. 
     Rawhide  16  shown in  FIG. 6  is not drawn to scale and is meant to be representative only. The size of perforated areas  27  and  28  will typically be larger to provide sufficient material for the bulbous ends  19  and  20  to be formed for the bone shaped dog chew shown in  FIG. 5 . In addition, some rawhide filler pieces may be rolled inside the perforated rawhide  16  in  FIG. 6  as it is rolled and shaped into the bone chew shown in  FIG. 5 . 
     In  FIG. 7  is shown a variant of the bone shaped dog chew shown in  FIG. 5  except the perforations are also cut into the rawhide material that forms the middle portion  27 . In such a case a piece of fully perforated rawhide, such as shown in  FIG. 3 , is utilized to form the bone shaped dog chew. 
     When a piece of rawhide  11  is processed to cut perforations there through the perforations may be cut in different ways. The piece of rawhide  11  may be processed with a cutting tool  21 , such as shown in  FIG. 8 , to cut the perforations. Cutting tool  21  is an example of a simple flat bed cutter that requires two passes of a piece of rawhide there through to cut the perpendicular sets of perforations. The perforations are cut by placing a piece of rawhide on top of tool  21  and applying pressure to the rawhide with a flat plate (not shown) that is positioned on top of the rawhide. The pressure forces the rawhide against the chisel edge cutters  22  which then cut through the rawhide creating the perforations. For example, with the first cut perforations  12  are cut. The rawhide is then rotated close to or at ninety degrees and is reprocessed in the same manner to cut perforation  13  through the rawhide using the same cutting tool  21 . When perforations  12  and  13  are cut at different times the pattern of the cuts will typically be somewhat random as shown in  FIG. 1 . In addition, perforations  12  ands  13  in  FIG. 1  may not be as closely to perpendicular to each other as is shown in  FIG. 1 . 
     Cutting tool  21  in  FIG. 8  is only a simple example of a flat bed cutter that can be used to cut perforations in a piece of raw hide  11 . On cutting tool  21  are shown six rows each having seven chisel edge cutters  22 . In reality there would be many more cutters  22  and only a small number of cutters are shown in  FIG. 8  to understand the invention with reference to a flat bed cutter. Since the simple cutting tool  21  shown in  FIG. 8  can cut rows of linear perforations in only one direction at a time, after cutting perforations (such as  12 ) on a piece of raw hide  11  in one orientation, the piece of raw hide  11  must be rotated approximately ninety-degrees and a second set of perforations (such as  13 ) is cut through the piece of raw hide  11 . Being as it would be difficult to perfectly orient the second set of perforations with respect to the first set of perforations the result will be as shown in  FIG. 1 . The two sets of perforations are not as neatly oriented with respect to each other as shown in  FIG. 2 . 
     Although not shown in the Figures, a flat bed cutter may be fabricated that has two sets of cutting blades set perpendicular to each other to concurrently cut neat sets of perforations  12  and  13  such as shown in  FIGS. 2 and 3 . When perforations  12  and  13  are cut through rawhide piece  11  at the same time the perforations can be cut exactly perpendicular to each other and be perfectly spaced from each other as shown in  FIGS. 2 and 3 . As shown in  FIG. 2  linear perforations  12  are each one-quarter inch long and they are spaced one-quarter inch from each other. The rows of linear perforations  12  are spaced one-quarter inch from an adjacent row of perforations  12 . The same applies to perforations  13 . In addition, perforations  12  and perforations  13  are specifically oriented perpendicular to each other as shown in  FIG. 2 . This size and spacing of perforations  12  and  13  is used to control the size of individual sections, which are small squares in  FIG. 2  bounded by pairs of perforations  12  and  13 . These dimensions help control how easily the individual sections will break from each other when a finished dog chew, such as shown in  FIGS. 4 ,  5  and  6 , is chewed by a dog. 
     The dimension of one-quarter inch used in the previous paragraph is not critical and may be changed. In addition, the perforations  12  and  13  may be of one length while the spacing between them lengthwise may be a different dimension, the lengths of perforations  12  and  13  may be of different from each other, the spacing between parallel rows of perforations may be different, the physical orientation of perforations  12  to perforations  13  may be different than as shown in  FIG. 2 , and the perforations need not be linear, etcetera. In addition, sets of perforations  12  and  13  need not be perpendicular to each other. 
     The design of the smaller sections bounded by perforations  12  and  13  can vary in shape or size. They may be square as shown in  FIG. 2 , rectangular, diamond, round oval or any other shape. The size of the perforations and the distance between the perforations in any direction can be varied depending on how easily it is desired to make the sections break off when the hide is chewed, and to set the size of the pieces that will break off. In addition, the dimensions may be changed depending upon the physical characteristics of the rawhide, such as thickness and hardness, which is being perforated and made into a dog chew. Further, the dimensions and shapes may be changed depending upon the type of dog chew being made, and the size of dog for which the dog chew is being made. A large dog can gnaw on a dog chew with larger sections and with sections that do not break off as easily as would be needed for a small dog. 
     Perforations  12  and  13  may also be cut through rawhide  11  in a manner different than using the flat bed cutter  21  shown in  FIG. 8 . Such an alternative method is a roll or drum type cutter shown in  FIG. 9 , and such an alternative method is actually preferred. The drum cutter comprises rollers  22  and  23 . Roller  22  has sets of cutter blades  24  and  25  protruding perpendicular from its surface. Cutter blades  24  cut perforations  14  through rawhide  11  and cutter blades  25  cut perforations  15  through rawhide  11 . As rollers  22  and  23  rotate, as depicted by the arctuate arrows on the end of the two rollers, rawhide  11  is drawn between the rollers as depicted by the linear arrow to the right side of the rawhide and perforations  14  and  15  are cut through rawhide  11  as shown. Due to the fact that the cutter blades  24  and  25  are mounted together on roller  22  the perforations will be cut through rawhide  11  in the exacting and repeatable pattern shown in  FIGS. 2 and 3 . On roller  22  are shown only a few rows each having eleven chisel edge cutters  25 . In reality there would be many more cutters  24  and  25  and the diameter of the rollers  22  and  23  would be larger. 
     In an alternate embodiment of the roll or drum type cutter, not shown in the Figures, cutter blades  24  may be protruding from the surface of roller  22  and cutter blades  25  may be protruding from the surface of roller  23 . 
     While what has been described hereinabove is a preferred embodiment of the invention and some alternative embodiments thereof, those skilled in the art will understand that numerous changes may be made without departing from the spirit and scope of the invention.