Abstract:
This invention is a small animal feeder that physically restricts access to food by medium to large size animals. It is comprised of a 12 inch cube of cardboard with an extra elongated front forming a vertical 3½ inch silt. A plastic feeder tray filled with food is inserted inside. It is the size and shape of the front opening that functions as both the barrier to medium to large size animals while allowing unlimited access to small animals. Currently used or patented pet feeders do not discriminate between medium to large size animals and smaller animals where access to dispensed food is concerned.

Description:
BACKGROUND 
     The field of endeavor to which this invention pertains is that of accessories for small animals and pets, and more specifically, a feeding system for smaller animals that can discriminate based on animal size to physically prevent access to the food by larger animals. 
     A pet owner who owns both larger and smaller animals, e.g., dogs and cats, encounters problems with their dogs eating their cat&#39;s food. Many pet owners like to leave cat food available to their cats 24 hours a day while feeding their dogs only once or twice a day. If cat food is left accessible to a dog, the dog is likely to eat the cat&#39;s food against the owner&#39;s wishes. 
     Traditional gravity operated cat feeders or any other mechanically operated cat feeders do not address this problem. For Example, U.S. Pat. No. 5,048,463 to Wilson, et al. will distinguish between large and small animals with an infrared detector but will not prevent a dog from taking a cat&#39;s food after the food is dispensed. 
     SUMMARY 
     An object of this invention is to provide a small animal feeder that discriminates according to size such that the food therein is not accessible by medium to large size animals. 
     According to one embodiment, the feeder&#39;s housing is comprised of a modified cardboard box to form a box-like shape having an elongated front with a narrow vertical slit shaped opening narrow enough to allow entry by smaller animals, such as cats, beyond the animal&#39;s shoulder region while preventing medium to large size animals, such as dogs, from accessing the inside of the housing beyond the animal&#39;s shoulder region. Inside the housing is a removable food tray where food is placed and replenished by hand. The tray is preferably removed and replaced in the housing via the narrow vertical slit shaped opening. 
     Alternatively, the housing may be made of a material other than cardboard, such as vinyl, plastic, wood, or metal. 
     The invention advantageously gives the owner of both pet cats and medium to large size dogs the ability to make cat food available to the cats 24 hours a day without the cat food being consumed by the dogs. 
     The materials used in this invention are comparatively simple, inexpensive, and easy to manufacture. The product can be assembled by the consumers, i.e., sold in a kit form. There is no required electrical devices, thereby simplifying the invention&#39;s manufacture and use. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top view illustrating the unassembled housing of the feeder according to an embodiment of the invention, where dashed lines show the placement of creases; 
     FIG. 2 is a side view illustrating the unassembled housing of the feeder according to an embodiment of the invention, where dashed lines show the placement of creases; 
     FIG. 3 is a top view illustrating the assembled housing of the feeder and food tray placement according to an embodiment of the invention; 
     FIG. 4 is front view illustrating the assembled housing of the feeder according to an embodiment of the invention; and 
     FIGS. 5A and 5B illustrate an exemplary fastening device for the housing according to an embodiment of the invention. 
    
    
     DETAILED DESCRIPTION 
     The housing of the invention defines an enclosed space that medium to large size animals can not access but can be accessed by smaller animals freely. The space can have multiple uses but the preferred embodiment of the invention described herein is sized accordingly to define a feeder that can not be accessed by medium to large size dogs while allowing free access to cats. 
     In the preferred embodiment illustrated in FIGS. 1-4, with particular reference to FIG. 4, the feeder housing is preferably comprised of ⅛ thick inch cardboard folded into a box with an additional elongated front which forms a narrow vertical slit shaped opening  400 . It is this narrow vertical slit shaped front opening  400  that functions as a physical barrier for medium to large size dogs while allowing cats free access to food placed inside the feeder. 
     Referring to the top view illustration of FIG. 1, the cardboard  100  can be manufactured according to conventional cardboard box manufacturing methods, with the modifications noted herein. Conventional creases  130  for the top rear flap  135  and bottom rear flap (not shown) are applied to the cardboard during the cardboard box manufacturing process. The cardboard  100  includes applied diagonal creases  110  in the front end at the top and bottom (bottom not shown) that are oriented such that triangular sub-flaps  120  are formed. These additional creases may be applied during manufacture or as a modification thereafter. Holes  160  are made in the front  120  and rear  135  flaps for fastening, as shown. Two additional flaps with holes at the bottom front are not visible in FIG.  1 . 
     Referring also to the side view illustration of FIG. 2, conventional creases  145 ,  155  for the side rear flap  140  and side front flap  150 , respectively, are also applied to the cardboard during the cardboard box manufacturing process. Holes  180  are made in the front  150  and rear  140  flaps for fastening, as shown. Two additional flaps with holes at the other side are not visible in FIG.  2 . 
     During folding, the holes  160  in the top and bottom flaps align with corresponding holes  180  in the side flaps so that a fastener can be asserted through both holes to hold the flaps together. For example, the nylon fastener-binders, shown in FIGS. 5A and 5B, are preferably used to bind the front and rear flaps. These fasteners are used in the preferred embodiment, but someone of ordinary skill in the art will appreciate that many other affixing means can be employed. For example, snaps may be secured to the flaps instead and used for fastening the flaps by snapping the corresponding male and female cooperating snap members together. Alternatively, another affixing means such as adhesive or Velcro can be used to fasten the flaps together. 
     As illustrated in FIG. 4, a food tray  300  can be placed near the rear of the assembled feeder housing. The food tray  300  can be comprised of plastic or metal materials. It should be noted, however, the food tray is not an essential feature of the invention. The food placement within the housing, however, is more important. 
     During assembly of the housing, the rear flaps  135  and  140  of the housing are folded along the respective creases  130  and  145  according to conventional cardboard box folding techniques so that a flat surface is formed at the rear of the housing. This being done, the respective holes for the top  160  and sides  180  on each of the four flaps cooperatively align. The fasteners are then placed through the holes and secured so that there are four fasteners installed at the rear of the housing. 
     The front of the feeder is assembled by folding the two front side flaps  150  along their creases  155  toward each other (see also FIG.  4 ). The two top front sub-flaps  120  are folded down along the respective creases  110  so that these fold over the front side flaps  150 . The holes  160 ,  180  in the top and side flaps are then aligned. The top. front sub-flaps  120  point directly down forming a 90 degree angle at the creases  110 . While the holes are held in alignment, the fasteners  500  are placed through the holes and secured. 
     The two bottom front sub-flaps  165  are folded up along their creases over the front side flaps  150 , forming a 90 degree angle at the creases  115 . The holes  160 ,  180  of the bottom and front side flaps are aligned and the fasteners  500  are secured. 
     The housing is then fully assembled as shown in the front view illustration of FIG.  4 . The assembled housing has a box-like shape having an elongated front with a narrow vertical slit-shaped opening, or aperture. The aperture dimensions are selected such that the width  410  is wide enough to allow entry by smaller animals, such as cats, beyond the animal&#39;s shoulder region, i.e., allow at least one front leg to enter the inner space of the housing. The width  410 , however, is also selected such that medium to large size animals, e.g., dogs, are prevented from accessing the inner space of the housing beyond the animal&#39;s shoulder region (e.g., scapula bone region). That is, the medium to large size animal cannot step into the housing at all. Consequently, the medium to large size animal cannot reach the food located in the removable food tray  300  located near the rear of the housing, since the head or shoulder region of the animal would press against the edges  420  defining the aperture. In the preferred embodiment, the width of the opening is in the range of 3.5 to 4 inches. 
     The dimensions of the housing are such that a medium to large size animal cannot reach the food located in the removable food tray  300  located near the rear of the housing without having to penetrate the interior of the housing beyond the animal&#39;s shoulder region. That is, the depth D shown in FIG. 3, is such that medium to large size animal&#39;s mouth cannot reach the food tray  300 , even if when the animal&#39;s head and neck can fit through the aperture up to the shoulder region. In the preferred embodiment, the depth D is about 15 inches, where a 12″ box is used a starting basis for the housing. 
     In the preferred embodiment, the housing is made of cardboard or another non-rigid material as to allow the edges  410  of the aperture to bend slightly when pressed against, as by a medium to large size animal attempting entry, to create a “pinching action” against the animals skin. This feature provides a disincentive for future attempts to access the feeder. 
     Alternatively, the housing may be made of a material other than cardboard, such as vinyl, plastic, wood, or metal, and can be rigid or non-rigid. 
     The invention advantageously gives the owner of both pet cats and medium to large size dogs the ability to make cat food available to the cats 24 hours a day without the cat food being consumed by the dogs. 
     The materials used in this invention are comparatively simple, inexpensive, and easy to manufacture. The product can advantageously be sold in an unfolded box form, as shown in FIGS. 1 and 2, to reduce shipping and storing costs and can be folded/assembled by the end user. There are no required electrical devices, thereby simplifying the invention&#39;s manufacture and use. 
     In operation, the feeder housing is placed on its side on any flat surface, such as a counter or table, with the elongated slit shaped opening in a horizontal position. Food is placed in the food tray. While holding the tray in a horizontal position, it is inserted through the horizontal opening of the feeder housing. Still holding the food tray in a horizontal position in one hand, the other hand rotates the cardboard feeder around the tray until the feeder opening is once again vertical. The food tray is moved to near the rear of the feeder and rests on the feeder bottom. 
     Removal of the food tray requires that either the feeder or an empty food tray be rotated 90 degrees such that the food tray and the feeder opening are aligned along the same axis. The tray is then removed. The position of the tray, as placed inside the feeder, is shown in FIG.  3 .