Abstract:
A dry particulate food dispenser provides food to pets in response to a scratching action upon a scratching surface. The scratching action operates an adjustable valve located inside a food hopper and limits the amount of food dropped into a supporting bowl. The adjustable valve allows the user to control the amount of food provided in each actuation of the valve and accommodates different shapes and sizes of dry food.

Description:
BACKGROUND 
     1. Field of Invention 
     This invention relates to dry particulate matter dispensers, specifically to feeders activated by the scratching action of cats. 
     2. Description of the Prior Art 
     Numerous patents exist which describe cat scratching posts or animal feeders. Scratching posts typically consist of a frame covered with carpet, burlap or coiled rope to provide a surface that cats like to scratch. The support, and assembly of such frames are the focus of many patents. 
     For example, U.S. Pat. No. 3,604,397 to Salerno 1971 discloses a cat perch and exercise pole that wedges itself between the floor and ceiling of a residence by leg projections on the top and bottom. These leg projections, under spring pressure press outward along the axis of the exercise pole securing the pole between the ceiling and floor. Salerno however, does not disclose, teach nor claim any element that provides food to the cat. 
     Numerous other patents exist with the aim to automatically feed animals. Many of these patents come from the field of animal husbandry where farmers are attempting to wean or fatten animals. Other patents aim to automatically feed pets without the aid of a human or the activation by an animal. Such devices are characterized by electrical solenoids or motors which are activated by one or more timers or light sensors. They have several disadvantages such as requiring batteries or a source of alternating current. Their components such as timers, motors, solenoids and sensors are costly. Additionally, the numerous parts of such inventions reduces overall reliability. Further, the size and complexity of these devices make them difficult to clean and move. Safety can also be a concern where water is in close proximity with line voltages. Since these devices are automatic, food may be dispensed when the intended recipient animal is not around, thus leaving the food available to wild animals or other pets. In the case of cats, automatic feeders to not provide a scratching surface or reward a cat with food for using a designated scratching surface instead of home furnishings. 
     For example, U.S. Pat. No. 5,735,231 to Terenzi 1998 discloses an automatic dog and cat feeder. A timer operates a solenoid to retract a slide valve to dispense food by gravity from a hopper. The length of time that the timer activates the solenoid determines the amount of food delivered. U.S. Pat. No. 5,794,560 also to Terenzi 1998 discloses another automatic dog and cat feeder. A timer operates a solenoid to retract a single cone valve to dispense food by gravity from a hopper. The length of time that the timer activates the solenoid determines the amount of food delivered. Again, relying upon timers, Terenzi does not suggest, disclose, teach or claim any combination of elements which enable actuation by a cat. 
     Similarly U.S. Pat. No. 5,138,979 to Baird et al 1992 uses an electric solenoid to activate a sliding metering head. The metering head however in Baird&#39;s own words is limited to a particle size of up to 4 mm. To accommodate various sizes of fish food he teaches the substitution of different sizes of metering heads. For larger material Baird replaces the metering head with a single valve mechanism. Baird states that the valve opens “for the free flow material from the container. In this case, the control over the quantity dispensed is achieved by timing the opening of the device.” Thus while Baird recognizes the problems associated with a single valve, he does not suggest, disclose, teach or claim any way to solve unlimited delivery except by timing the operation of the electric solenoid. Further Baird does not even suggest actuation by a cat. 
     There exist a number of animal actuated feeders. 
     U.S. Pat. No. 1,309,090 to Hensen discloses a feeding device. Hensen uses a cylindrical valve to open and close an opening in the bottom of the feed hopper. The valve is opened by the instinctive rooting action of a pig. Hensen does not disclose or suggest a means to limit the amount of feed delivered when the valve is open. Once the valve is opened by the pig, the feed contents of the hopper are free to flow without limit. Hensen himself admits that his device is “adapted for use in connection with hogs and kindred stock”. Because the feeding device is actuated by the upward rooting action of hogs and kindred stock, it is not possible to operate the device by the instinctive scratching action of cats. While hogs and kindred stock, root in a down to upward motion, cats instinctively scratch in an up to downward motion. It is obvious that Hensen did not anticipate adaptation of his device for use by cats. 
     Hensen does not suggest, disclose, teach or claim any combination of elements which enable actuation by a cat. 
     U.S. Pat. No. 4,799,455 1989 discloses a farrowing crate creep feeder. The inventor uses a conical valve to open and close an opening in the bottom of the feed hopper. The valve is opened by the instinctive rooting action of a pig. This patent does not disclose or suggest a means to limit the amount of feed delivered when the valve is open. Once the valve is opened by the pig, the feed contents of the hopper are free to flow without limit. Because the creep feeder is actuated by the upward rooting action of piglets, it is not possible to operate the device by the instinctive scratching action of cats. While piglets, root from a down to upward motion, cats instinctively scratch in a downward motion. It is obvious that this invention did not anticipate adaptation for use by cats. The disclosure does not suggest, disclose, teach or claim any combination of elements which enable actuation by a cat. 
     U.S. Pat. No. 6,053,124 to Kolbe 2000 discloses an apparatus for feeding granulated feed supplements to livestock. Kolbe uses the licking action of bovines or similar animals to dispense feed supplements such as salt. As an animal licks an actuating block, a stopper is raised from a lower to upper position allowing the supplement to fall through the actuating block. Kolbe provides no mechanism to limit the amount of supplement delivered. Although the invention shows a stop rod to limit the travel of the stopper, nothing prevents the supplement from flowing around the stopper. The invention of Kolbe is suited to the licking motion of animals, but is not suitable to the scratching action of cats. Kolbe does not suggest, disclose, teach or claim any combination of elements which enable actuation by a cat. 
     U.S. Pat. No. 5,113,795 to Delzio 1992 and its reissue U.S. Pat. No. Re 35,173 in 1996 disclose a cat scratch post feeder. Delzio uses the instinctive scratching action of a cat to dispense feed into an unattached bowl. Delzio supports his device either from a wall or a free standing base, but does not provide for any means to keep the bowl under the feeder. Some of Delzio&#39;s embodiments require tools and installation to a wall or other household structure. Additionally, Delzio relies upon a spring loaded door or lid located at the bottom of a food hopper. However, the weight of the food rests directly upon the door or lid. This limits the amount of feed that the hopper can hold before the weight of the feed, overcomes the closure spring, dumping feed into the bowl or floor. Furthermore, the weight of the food in the hopper, changes the force that a cat must exert on the scratching surface before feed is dispensed. When the hopper is full, feed dispenses easily, when the hopper is near empty, feed dispenses only with great effort on the part of the cat. Still further, there is no means to limit the amount of feed dispensed once a cat pulls down upon the scratching surface. It is possible to empty the contents of the hopper if the cat were to set its claws in the scratching surface and stretch as cats are known to do. Nor does Delzio provide any mechanism to adjust the feeder to accommodate different sizes or amounts of cat food. 
     OBJECTS AND ADVANTAGES 
     Accordingly, several objects and advantages of the invention are: 
     (a) to provide a pet activated feeder that does not rely upon batteries or external electrical power; 
     (b) to provide a pet feeder that limits the amount of feed per activation cycle and does not dump its contents uncontrollably; 
     (c) to provide an adjustable feeder that can be adjusted to suit the various types of feed available; 
     (d) to provide a feeder that does not rely upon the independent placement of a feeding bowl to catch the distributed feed; 
     (e) to provide a feeder that is simple in its construction and inexpensive; 
     (f) to provide a feeder that is portable; 
     (g) to provide a feeder that is easy to clean; 
     (h) to provide a feeder that makes food available to cats but frustrates the attempts of other animals like dogs and birds; 
     (i) to provide a feeder that acts as a substitute scratching surface for cats thus reducing damage to household furnishings and decorations due to scratching; 
     (j) to provide a feeder that provides food on-demand in contrast to dispensing it at predetermined times whether or not a pet is present to eat it. 
     (k) to provide a feeder that does not require tools to assemble. 
     (l) to provide a feeder that does not require attachment to a wall or other structure. 
     Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with the present invention, a bowl shaped base supports a feed hopper which is closed at its lower end by a valve mechanism. A scratching surface, placed over the feeder hopper, is supported by elastic bands attached to the hopper. As the scratching surface, actuated by a cat, moves up and down, it activates the valve mechanism. Upon activation, the valve mechanism dispenses a limited amount of feed from the hopper into the bowl shaped base. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an external view of the dispenser with a cut-away view showing the valve assembly; 
     FIG. 2 is a view of the dispenser base; 
     FIG. 3 is an exploded view of the dispenser; 
     FIG. 4 is an exploded view of the valve assembly; 
     FIG. 5 is a view of the valve assembly with the valve in the lower position; 
     FIG. 6 is a view of the valve assembly with the valve in the upper position; 
     FIG. 7 is a sectional view of the valve assembly in FIG. 5; 
     FIG. 8 is a sectional view of the valve assembly in FIG. 6; 
     FIGS. 9A and 9B are of the valve linkage; 
     FIG. 10 is sectional view of an alternate embodiment of the valve assembly. 
     FIGS. 11A-11D are a views of an alternate valve assembly embodiments. 
    
    
     LISTING OF REFERENCE NUMERALS 
       10  Food hopper, 
       12  Filling end, 
       13  Anchor points, 
       14  Dispensing end, 
       16  Linkage slots, 
       20  Scratching surface, 
       22  Lid, 
       32  Bowl, 
       34  Support structure, 
       36  Channel 
       40  Valve assembly, 
       42  Valve body, 
       44  Movable valve, 
       48  Valve body intake, 
       50  Upper valve, 
       51  Upper valve hole, 
       52  Lower valve, 
       53  Lower valve hole, 
       54  Valve stop, 
       55  Adjustable attachment, 
       56  Valve shaft, 
       57  Valve shaft upper end, 
       58  Knob, 
       59  Valve shaft lower end, 
       60  Valve plate, 
       62  Valve sleeve, 
       64  Valve cap, 
       65  Valve cap hole, 
       66  Suspension spring, 
       68  Valve plate orifice, 
       70  Compression spring, 
       72  Spring rest, 
       73  Spring rest hole, 
       74  Spring cap, 
       80  Valve linkage, 
       82  Suspension spring attachment, 
       84  Valve assembly contact point. 
       90  Attractive scent. 
     DETAILED DESCRIPTION 
     Description of Preferred Embodiment 
     FIG. 1 shows an external view of the dispenser with a cut-away view showing an internal valve assembly  40 . A base  30 , with an integral bowl  32 , has a support structure  34 , to support a food hopper  10 . Co-axially located around the food hopper  10 , is a scratching surface  20 . The scratching surface  20  is suspended from the food hopper  10 , by elastic bands (not shown). Internal to the food hopper  10 , Is a valve assembly  40 , which prevents the dry particulate food in the upper part of the food hopper  10 , from exiting the dispensing end  14  at the lower part of the food hopper  10 . 
     FIG. 2 shows a more detailed view of the base  30 . The base  30  includes a bowl  32 , and a support structure  34 . A channel  36  connects the support structure  34  to the bowl  32 . In the preferred embodiment, the base  30 , is made of any of a number of types of durable, rigid, plastic. Examples of suitable plastics include, but are not limited to poly vinyl chloride, poly propylene, and poly ethylene. The base is formed by any number of conventional plastic fabrication techniques including but not limited to injection molding, thermal forming, rotational molding and numerically controlled machining. All of these plastics and forming techniques are familiar to those skilled in the art of plastic fabrication and mass production. The size and shape of the base  30  are determined by the weight and height of the food hopper  10 , scratching surface  20  and valve assembly  40  (FIG.  1 ). In use, the base  30 , typically rests on a flat surface such as a floor and must be wide enough and heavy enough to prevent the dispenser from tipping when an animal such as a cat scratches its front paws against the scratching surface  20  (FIG.  1 ). The size and shape of the lower or dispensing end  14  of the food hopper  10 , shown in FIGS. 1 and 4, determine the size and shape of the support structure  34 . In the preferred embodiment, the support structure  34 , receives the dispensing end  14  by a slip fit without the use of tools or fasteners. Other conventional joining techniques such as gluing, plastic welding, threading, screwing and integral manufacture are also possible. 
     FIG. 3 shows an exploded view of the dispenser. The food hopper  10  is a hollow cylinder approximately 40 cm in height and 10 cm in diameter although other heights and diameters are possible and the exact measurements are not critical to the operation of the dispenser. The materials and fabrication techniques of hopper  10  are similar to the base  30 . The preferred embodiment uses 10 cm (4 inch) thin wall poly vinyl chloride drain pipe. As will be explained in the operation section of this disclosure, the upper end of the food hopper  10 , is called the filling end  12  and the lower end is called the dispensing end  14 . Two linkage slots  16 , are located toward the dispensing end  14 . The linkage slots  16  are approximately 5 cm in length and are wide enough to allow an easy sliding fit of the valve linkage  80  without binding. Two anchor points  13  near the filling end  12  fix one end of the suspension springs  66  to the food hopper  10 . The valve assembly  40  slides into the food hopper  10  such that the valve plate  60  is above the linkage slots  16 . The valve assembly  40  is fixed to the food hopper  10 . The method of fixing the valve assembly  40  within the food hopper  10  can be by any number of conventional methods including gluing, screws, pins, or crimps. The preferred method is to decrease the inner diameter of the food hopper  10  just above the linkage slots  16 , and to make the outer diameter of the valve plate  60 , a little larger to create a sliding fit inside of the food hopper  10 , until it wedges or rests on a section of decreased diameter. In this embodiment, the valve assembly  40  installs from the filling end  12 . 
     The valve linkage  80 , slides into the linkage slots  16 , and under the valve assembly  40  and valve plate  60 . Suspension springs  66  attach to the food hopper  10  at the two anchor points  13  and attach to the valve linkage  80  at the suspension spring attachment points  82  shown in detail in FIGS. 3,  9 A and  9 B. The suspension springs  66  are tension springs that urge the valve linkage  80  upward in the linkage slots  16  to contact part of the valve assembly  40 . The suspension springs can be any suitable type of durable elastic material including, but not limited to rubber bands, surgical tubing, bungee-type cords, and metal springs. Instead of suspension springs, a counter-weight system is also possible. 
     The scratching surface  20  together with a lid  22  form a cylinder with the upper end closed. Materials suitable for the scratching surface  20  include but are not limited to, carpet, wood, plastic and fiber rope. The preferred material is nylon carpet conventionally butt welded to itself to form a cylinder with a plastic lid  22  closing the one end. The inner diameter of the scratching surface cylinder  20  is approximately 1 or 2 cm larger than the outer diameter of the food hopper  10  so as to have a loose sliding fit over the food hopper  10 , the anchor points  13  and the suspension springs  66 . The diameter of the scratching surface  20  must be smaller than the length of the valve linkage  80  such that the lower open end of the scratching surface  20  rests upon the valve linkage  80 . The tension in the suspension springs  66  is such that the suspension springs  66  bias the valve linkage  80  at the upper portion of the linkage slots  16  and thereby support the weight of the scratching surface  20 . When properly sized, the scratching surface  20  easily slides over the food hopper  10  and moves the valve linkage  80  from the upper to lower ends of the linkage slots  16 . 
     FIG. 4 shows an exploded view of the valve assembly  40 . Two major subassemblies, the valve body  42  and the movable valve  44  make up the valve assembly  40 . The valve plate  60 , valve sleeve  62  and valve cap  64  together make up the valve body  42 . The outer diameter of the valve plate  60  is such that the valve plate  60  is a sliding fit inside the food hopper  10 . Thus the valve plate  60  prevents the passage of dry particulate food through the food hopper  10 . The only way for food to get past the valve plate  60  is to pass through the valve plate orifice  68 . The valve cap  64  closes the upper end of the valve body  42 . One or more holes in the valve body serve as valve body intakes  48  and allow dry food to enter the valve body  42  and exit out the valve plate orifice  68 . 
     Collectively, the upper valve  50 , the lower valve  52 , the valve stop  54 , valve shaft  56 , adjustable attachment  55  (FIGS. 5,  7  and  8 ) and knob  58  form the movable valve assembly  44 . Two valves, an upper valve  50  and a lower valve  52  are located on opposite sides of the valve plate  60 . A valve shaft  56  passes through the centers of both the upper valve  50  and the lower valve  52 . In the preferred invention, the lower valve  52  is adjustably attached to the valve shaft  56 . There are a number of ways to implement the adjustable attachment  55 . The preferred method is to externally thread the valve shaft  56  and form matching internal threads on the lower valve  52 . An adjustment knob  58  can then rotate to adjust the depth of the valve shaft  56  within the lower valve  52 . Another adjustment method can be a sliding detent mechanism between the lower valve  52  and valve shaft  56 . The valve shaft  56  passes through the valve plate  60  and into a hole in the upper valve  50 . The upper valve hole  51  is such that the upper valve  50  easily slides along the valve shaft  56  without restriction. The relative size between the valve sleeve  62  and the upper valve  50  is such that the upper valve  50  slides within the valve sleeve  62 . The upper valve  50  and lower valve  52  are cone shaped with a major diameter large enough to block the valve plate orifice  68  thus preventing the passage of dry food. The valve stop  54  attaches firmly to the valve shaft  56 . As the valve shaft  56  is adjusted within the lower valve  52 , the valve stop  54  moves with the valve shaft  56  and determines the minimum spacing between the upper valve  50  and the lower valve  52 . In the preferred embodiment, all the parts of the valve assembly  40  are co-axial. In this co-axial arrangement, the upper valve  50  and lower valve  52  are co-located at their narrow portions to form an hour glass like shape. The valve stop  54 , located between the narrow portions of the valves, determines the distance between the valve ends. Thus the neck of the hour glass like shape is adjustable by operation of knob  58 . 
     FIGS. 5 and 6 show the two positional limits of the movable valve  44  within the valve body  42 . FIG. 5 shows movable valve  44  in a lower or second position while FIG. 6 shows the movable valve  44  in an upper or first position. 
     FIGS. 7 and 8 are section views of FIGS. 5 and 6 respectively with the direction of the movable valve  44  indicated by the arrows A. FIGS. 5 and 7 show the upper valve  50  closing the valve plate orifice  68 . As the valve shaft  56  moves downward, the valve stop  54  allows the upper valve  50  to progressively block the valve plate orifice  68  until the cone of upper valve  50  substantially blocks the valve plate orifice  68 . 
     FIGS. 6 and 8 show the lower valve  52  closing the valve plate orifice  68 . As the valve shaft  56  moves upward, the valve stop  54  pushes the upper valve  50  out of the valve plate orifice  68 . As valve shaft  56  continues to move upward, the lower valve  52 , which is attached to the valve shaft  56  progressively blocks the valve plate orifice  68  until the cone of lower valve  52  substantially blocks the valve plate orifice  68 . When the movable valve  44  is in the upper or first position, dry food can enter the valve body  42  through the valve body intakes  48 . 
     FIGS. 9A and 9B show details of the valve linkage  80 . In the preferred embodiment, the valve linkage  80  is made of stiff wire such as 0.100 inch stainless steel, although other materials and thicknesses are possible. Valve linkage  80  has two suspension spring attachments  82  formed by a notch or bend at the ends of valve linkage  80 . Suspension springs  66  (FIG. 3) attach to valve linkage  80  at suspension spring attachments  82 . Valve assembly contact point  84 , in the approximate center of valve linkage  80  contacts lower valve  52  (FIGS. 4-8 and FIG.  10 ). The bend at valve assembly contact point  84 , allows for clearance of the valve shaft  56  and valve knob  58  (FIGS. 4-8 and FIG.  10 ). 
     Operation of the Preferred Embodiment 
     When an animal scratches the scratching surface  20 , the additional downward force on the scratching surface  20  will push on the valve linkage  80  and overcome the force of the suspension springs  66 . As the valve linkage  80  slides down in the linkage slots  16 , the valve linkage  80  allows the movable valve  44  to fall along the direction of arrows A (FIGS.  5  and  7 ), under gravity to the lower or second position. Dry food located in between the upper valve  50  and lower valve  52  falls past lower valve  52 , out of the dispensing end of food hopper  10 , down the channel  36  and into the bowl  32 . The upper valve  50  falls to close the valve plate orifice  68  preventing further dry food from exiting the food hopper  10 . Because the upper valve  50  is not rigidly fixed to the valve shaft  56 , the remainder of the movable valve assembly  44  can move downward completely even if dry food becomes trapped between the upper valve  50  and the valve plate  60 . This sliding upper valve feature reduces jamming 
     When the animal releases the scratching surface  20 , the suspension springs  66  urge the valve linkage  80  and the scratching surface  20  upward along the directions of arrows A (FIGS.  6  and  8 ). As the valve linkage  80  travels upward within the linkage slots  16 , the valve linkage  80  pushes against the lower valve  52  and moves the valve assembly  44  upward until the lower valve  52  blocks the valve plate orifice  68 . This upper or second position prevents food from leaving the food hopper  10 . The upper valve  50 , lifted by the valve stop  54  moves upward and away from the valve plate orifice  68  and exposes the valve body intakes  48  to the food within the food hopper  10 . The food enters the valve body  42  into the space between the upper valve  50  and the lower valve  52 . The next scratching up and down cycle dispenses the food located in the valve body  42 . The valve sleeve  62  and valve cap  64  support the weight of food in the food hopper  10  which might otherwise push down upon the upper valve  50 . The adjustable attachment  55 , (FIGS.  4 - 8 ), adjusted by the knob  58 , moves the valve stop  54 , relative to the lower valve  52 . This adjustment controls the minimum distance between the upper valve  50  and the lower valve  52  and thus the amount of food that can fill the space between them. 
     Description of Alternative Embodiment 
     FIG. 10 shows valve assembly  40  in cross section. Valve shaft  56  extends through valve cap  64  via a valve cap hole  66 . Refer now to FIG.  3 . In this alternate embodiment, the valve shaft  56  extends past the filling end  12  of food hopper  10 . The lid  22  of scratching surface  20  can now rest upon the extended valve shaft  56  (FIG.  10 ). Refer again to FIG.  10 . The valve body  42  contains additional components; a compression spring  70 , a spring rest  72  with a spring rest hole  73  and a spring cap  74 . The spring rest  72  is rigidly fixed to the inside of the valve sleeve  62  and supports spring  70 . The spring cap  74  attaches to valve shaft  56  either rigidly or adjustably by threads or other means. Spring cap  74  is positioned in either case to compress the compression spring  70  thus exerting an upward force on valve shaft  56 . This upward force acts to urge movable valve  44  to the upper position. 
     Employing the embodiment of FIG. 10, compression spring  70  holds the movable valve  44  in the upper position. This eliminates the need for the suspension springs  66 , linkage slots  16 , valve linkage  80 , or anchor points  13  of FIG.  3 . Compression spring  70  is sized to provide sufficient upward force on the valve shaft  56  to position the movable valve  44  to the upper position and simultaneously support the weight of scratching surface  20 . In this embodiment, the underside of lid  22  of scratching surface  20  rests on valve shaft  56  as valve shaft  56  extends past the filling end of  12  of food hopper  10 . 
     Operation of Alternative Embodiment 
     Referring to FIG. 10, compression spring  70 , supported by spring rest  72  acts against spring cap  74  and exerts an upward force on extended valve shaft  56 . As valve shaft  56  moves upwards, it urges moveable valve  44  into an upper or first position analogous to the positions shown in FIGS. 6 and 8. Additionally, as valve shaft  56  passes through valve cap hole  65 , it contacts and supports lid  22  and therefore attached scratching surface  20  (FIGS.  1  and  3 ). As an animal exerts a downward scratching force on scratching surface  20 , the force is transmitted to lid  22 , valve shaft  56  and movable valve  44 . As valve shaft  56  moves downward under this force, it urges moveable valve  44  into an lower or second position analogous to the positions shown in FIGS. 5 and 7 thus opening the valve and dispensing food. 
     If spring cap  74  is adjustable along valve shaft  56 , the compression force exerted by compression spring  70  can be varied. Such an adjustment feature can be employed to accommodate various weights of scratching surface  20  or to demand more effort from the scratching animal. 
     Additional Embodiments—Attractive Scent 
     As a training aid, an attractive scent  90  (FIG.  1 ), is applied to the scratching surface  20 . The attractive scent  90 , can be any one of commercially available scents applied as an aerosol, power, spray or herb. For cats, a commonly available cat nip spray is applied to the scratching surface  20  encouraging cats to investigate and scratch the scratching surface  20 . Once acquainted with the food delivery feature of the invention, animals quickly learn to use it without the further enticement of the attractive scent  90 . 
     Additional Embodiments—Valve Shapes 
     The preferred embodiment described upper valve  50  and lower valve  52  as conical in shape, but innumerable other shapes are possible. For example, FIG. 11A shows upper valve  50  with a cylindrical shape, while FIG. 11B shows lower valve  52  with a cylindrical shape. 
     Additional Embodiments—Lower Valve Only 
     While the preferred embodiment employs and upper valve  50  and a lower valve  52 , it is possible to use only a lower valve  52 . FIGS. 11C and 11D show movable valve  44  with a lower valve  52  only without an upper valve  50 . 
     Additional Embodiments—Non-Adjustable 
     The preferred embodiment described an adjustable attachment  55  controlled by a knob  58 . It is possible to fix the lower valve  52  to the valve shaft  56  and thereby fix the distance between the upper valve  50  and lower valve  52 . this embodiment eliminates the need for an adjustable attachment  55  and knob  58 . 
     Additional Embodiments—Non-Slidable Upper Valve 
     The preferred embodiment described the upper valve  50  slideably located on the valve shaft  56 . An alternative embodiment is to fix the upper valve to the valve shaft  56 . This embodiment can be practiced with or without the adjustable attachment  54 . 
     Conclusions, Ramifications and Scope 
     Thus the reader will see that the dry particulate food dispenser of the invention: 
     provides a pet activated feeder that does not rely upon electrical power; 
     provides a pet feeder that limits the amount of feed per activation cycle; 
     provides adjustment mechanism to suit the various types of feed available; 
     provides an integral feeding bowl; 
     does not rely upon the independent placement of a feeding bowl to catch feed; 
     provides a feeder that is simple in its construction and inexpensive; 
     provides a feeder that is portable; 
     provides a feeder that is easy to clean; 
     provides a feeder that makes food available to cats but frustrates the attempts of other animals like dogs and birds; 
     provides a feeder that acts as a substitute scratching surface for cats thus reducing damage to household furnishings and decorations due to scratching; 
     provides a feeder that provides food on-demand in contrast to dispensing it at predetermined times whether or not a pet is present to eat it; 
     provides a feeder that does not require tools to assemble; 
     provides a feeder that does not require attachment to a wall or other structure. 
     While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one preferred and alternate embodiments thereof Many other variations are possible including valve and bowl shapes, colors and textures. Various materials can be used in the construction, and interchangeable colored or decorated scratching surfaces might be changed with the season, holiday or decor. 
     Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.