Abstract:
A nutcracker utilizes a conical member with a textured exterior surface rotatably mounted and centered inside a vertical cylinder with a textured interior surface. The nuts occupy a cracking zone between the textured exterior surface and the textured interior surface. As the conical member rotates, gravity rolls the nuts down in a spiraling path into an increasingly smaller cracking zone until the pressure on the nuts between the textured exterior surface and the textured interior surface causes the shells to crack and the nuts to break into halves and thirds.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to machines for cracking multiple nuts. More particularly, it cracks nuts by rolling them between two surfaces which move relative to one another and become closer together, increasing the pressure on the nuts as the nuts are pulled downward by gravity into a smaller cracking zone. 
   2. Related Art 
   Power, U.S. Pat. No. 1,194,318, discloses a conical hopper, a conical rotor mounted within the hopper, means for operating the rotor, there being a downwardly decreasing inter-space between the rotor and the hopper, the hopper being provided with downwardly ranging channels formed in its inner walls, and the rotor being provided with spirally produced channels in its periphery, said channels in the hopper walls being angular in formation and separated by edge portions to which the material is presented upon the rotation of the rotor, and the rotor being provided in the channels with spaced pins projecting beyond the periphery of the rotor. 
   Spitz, U.S. Pat. No. 1,274,803, discloses a cone-shaped hopper or shell with vertically-disposed ribs on its upper portion and teeth on its bottom portion, and an upright conical member with spiral ribs on its upper portion and teeth on its lower member, the teeth of the hopper and conical member having abrupt faces facing in opposite directions. 
   Dragon, U.S. Pat. No. 2,129,679, discloses two conical members concentrically mounted one within the other so as to provide a downwardly diminishing substantially annular and conical space or chamber. 
   Kasser, U.S. Pat. No. 2,302,227, discloses a process of cracking and shelling nuts which consists in rolling the nuts between opposite compressible surfaces so that the nuts are partly embedded in said surfaces, and forcing the rolled nuts at intervals on said surfaces over rigid cracking surfaces. 
   SUMMARY OF THE INVENTION 
   The present invention is a nutcracker comprising a conical member with a textured exterior surface inside a vertical cylinder with a textured interior surface. Nuts are placed in the space between the conical member and the vertical cylinder. As the conical member rotates within the vertical cylinder, gravity forces the nuts to roll downward into a cracking zone of increasingly reduced space, until the pressure between the conical member and the vertical cylinder causes the shells of the nuts to crack. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings illustrate several aspects of embodiments of the present invention. The drawings are for the purpose only of illustrating preferred modes of the invention, and are not to be construed as limiting the invention. 
       FIG. 1  is a perspective view of the preferred embodiment of the present invention. 
       FIG. 2  is another perspective view of the preferred embodiment shown in  FIG. 1 . 
       FIG. 3  is an exploded view of the preferred embodiment shown in  FIGS. 1-2 . 
       FIG. 4  is a front view of the preferred embodiment shown in  FIGS. 1-3 . 
       FIG. 5  is a bottom view of the preferred embodiment shown in  FIGS. 1-4 . 
       FIG. 6  is a top view of the preferred embodiment shown in  FIGS. 1-5 . 
       FIG. 7  is a rear view of the preferred embodiment shown in  FIGS. 1-6 . 
       FIG. 8  is a side view of the preferred embodiment shown in  FIGS. 1-7 . 
       FIG. 9  is a cross-sectional view of the preferred embodiment shown in  FIGS. 1-8  taken from the side. 
       FIG. 10  shows the conical member and rod of the preferred embodiment shown in  FIGS. 1-9 . 
       FIG. 11  shows the vertical cylinder, handles, and chute of the preferred embodiment shown in  FIGS. 1-9 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The preferred embodiment of the present invention is a nutcracker  10  which cracks the shells of nuts  2  by utilizing gravity to roll the nuts  2  downward into an increasingly narrow cracking zone  15  between a vertical cylinder  40  and a conical member  20 , as shown in  FIG. 9 . A description of the preferred embodiment of the invention follows. 
   The vertical cylinder  40  is the structural core of the nutcracker  10 . An open cylindrical shape, with open circles at each end and walls extending perpendicularly to the planes of the circles, is preferred because of its ease of manufacture. The vertical cylinder  40  is preferably formed from a rectangular sheet of metal formed into a right, circular cylinder, and welded together at the ends that come together, and preferably has a diameter of eight inches. Tread plate is preferred for the sheet of metal because it is readily available and inexpensive in the welding industry, and easy to form into the desired cylindrical shape. Its elongated protrusions  41  that extend no more than one-eighth of an inch from the surrounding plate surface and are at right angles to each other “woven” into a pattern at regular intervals as shown in  FIGS. 1 ,  3 ,  9 ,  10 , and  11 , allow the vertical cylinder to grip the nuts  2  to be cracked. The vertical cylinder  40  will preferably be formed with the treads facing inward, forming a textured interior surface  42  of the vertical cylinder. It is envisioned that tread plate with textures other than that shown, or rigidized metal or dimpled metal could be used as alternatives to the illustrated tread plate. The sheet of metal may be made of any kind of steel; however, stainless steel is preferred because it is the most sanitary material and easily washed. Aluminum, on the other hand, would wear down after repeated use and is therefore not desired. 
   The vertical cylinder  40  preferably has handles  45  welded onto each side of the vertical cylinder  40 , which allow the nutcracker  10  to be carried and controlled once the nutcracker  10  is placed on the work surface. Welded onto the bottom of the vertical cylinder  40  will preferably be a bottom plate  56 , which prevents the vertical cylinder  40  from digging into the work surface. 
   Four eight-pound manual release suction cups  80 , each two inches in diameter, are preferably bolted onto the bottom plate  56 , to prevent the nutcracker  10  from moving once it has been placed on the work surface; push-button suction cups could also be used. However, the nutcracker  10  could also be clamped onto the work surface, or even bolted onto the work surface. 
   A first cross-arm bearing support  50  will preferably be attached at or near the top or the vertical cylinder  40 ; it is envisioned that the first cross-arm bearing support  50  could either be welded onto the vertical cylinder  40  directly, or fastened onto landings  44  which are welded onto the vertical cylinder  40 . The first cross-arm bearing support will preferably have a one-inch first bearing  51  attached to it which is configured to receive a rod  28  and allow the rod  28  to spin in the center of the vertical cylinder  40 . The first cross-arm bearing support  50  will preferably also have smaller holes which are configured to receive bolts for the purpose of attaching a hopper  60  to the vertical cylinder  40 . 
   The hopper  60  is preferably an inverted partial cone, and serves as a funnel to allow more nuts  2  to be placed into the nutcracker  10 . The hopper  60  is manufactured as a separate piece from the vertical cylinder  40 . The hopper  60  is preferably made of sixteen-gauge sheet metal. The hopper  60  preferably has a horizontal plate  62  with small holes adapted to receive bolts, as well as a pair of slanted plates  64  with apertures adapted to receive bolts, all three plates being welded onto the hopper  60 . Means other than bolts to fasten the hopper  60  to the vertical cylinder  40  are envisioned. The slanted plates  64  are slanted to allow the nuts  2  to fall down into the vertical cylinder  40 . The configuration of horizontal plate  62  and slanted plates  64  have the purposes of securing the hopper  60  to the vertical cylinder  40 , and preventing hands from going into the vertical cylinder  40  and becoming injured. When the hopper  60  is placed onto the vertical cylinder  40 , the hopper  60  and vertical cylinder  40  preferably form an angle of 161 degrees. 
   As shown in  FIG. 9 , a first plate  54  is preferably attached to the entire interior perimeter of the vertical cylinder  40 . The first plate  54  preferably is made of sheet metal and has a smooth top surface, has a hole in its center that is adapted to allow a rod  28  to pass through and spin, and is slanted from the horizontal to allow shelled nuts  2  (comprising nut meat  2 ′ and shells  2 ″) to slide down along the first plate  54  and out of the vertical cylinder  40  through an opening  55  in the vertical cylinder  40 , preferably exiting the vertical cylinder  40  along a spout  46 . 
   The spout  46  is preferably made from the same piece of sheet metal as the first plate  54 , and preferably has a bottom portion  48  which is parallel to the first plate  54 , and two side portions  49  which serve to guide the nuts  2  in a uniform direction as they exit the nutcracker  10 . 
   A second plate  52  is preferably attached to the vertical cylinder  40  and to the bottom of the first plate  54 , and has a one-inch second bearing  53  configured to receive a rod  28  and allow the rod  28  to spin. Below the second plate  52  is a bevel gear comprising a first bevel wheel  74  and a second bevel wheel  76 . The first bevel wheel  74  is keyed to hold the rod  28  in place, the rod  28  also being keyed at its bottom end. The second bevel wheel  76  meshes with the first bevel wheel  74 . The second bevel wheel  74  is attached to a shaft  72  and crank  70 , which allow the user to turn the rod  28  within the vertical cylinder  40 , causing the conical member  20  to rotate. However, it is envisioned that there are other ways to turn the rod  28  and conical member  20 , such as with a motor with two sprockets and a chain, or by using a rod  28  long enough to extend beyond the hopper  60  and connected to a crank to the top end of the rod  28 . 
   The second essential element of the nutcracker  10  besides the vertical cylinder  40  is the conical member  20 . The conical member  20  is centered in the vertical cylinder  40 . The conical member  20  preferably has a broad end  26  with diameter of seven inches, a narrow end  24  with diameter of four-and-one-half inches, and a height of eight inches. The conical member  20  is preferably hollow. It is preferably made of the same material as the vertical cylinder, with the treads facing outward to form a textured exterior surface  22 . For manufacture of the conical member  20 , the tread plate is cut with two arcs of different radii centered upon the same point. A sheet of metal, preferably also tread plate, is also used to close the narrow end  24  of the conical member  20  and the broad end  26  of the conical member  20 . However, if tread plate is used to close the narrow end  24  and the broad end  26 , the treads will face inward so that the exterior portions of the narrow end  24  and broad end  26  are smooth. A single rod  28  preferably extends through and is welded into the center of the narrow end  24  and the broad end  26 . The rod  28  preferably has a diameter of one inch. However, two separate rods could also be used, with one extending from the narrow end  24  and the other extending from the broad end  26 , and still achieve the purposes of the invention. The angle  92  between the textured exterior surface  22  and the broad end  26  is preferably between 80 and 84 degrees, and most preferably 82 degrees. 
   The area between the textured exterior surface  22  and the textured interior surface  42  forms a cracking zone  15 . The textured interior surface  42  is vertical in the cracking zone  15 , as the textured interior surface  42  is preferably vertical at all points. The textured interior surface  42  is continuous from the top of the vertical cylinder  40  though the cracking zone  15  to the bottom of the vertical cylinder  40  because the vertical cylinder  40 , of which the textured interior surface  42  is a part, is inexpensively made from a single rectangular piece of sheet metal, preferably tread plate, bent into a right cylinder and welded together. The textured exterior surface  22  is also continuous from the narrow end  24  of the conical member  20  through the cracking zone  15  to the broad end  26  of the conical member  20  because the textured exterior surface  22  is also made from a single piece of sheet metal, preferably tread plate. 
   An angle  90  between the textured exterior surface  22  of the conical member  20  and the textured interior surface  42  of the vertical cylinder  40  causes the cracking zone  15  between the textured exterior surface  22  and textured interior surface  42  to decrease as the nuts  2  are pulled downward by gravity. As the conical member  20  spins within the vertical cylinder  40 , or alternatively, as the conical member  20  is alternately spun in one direction and then the other, gravity causes the nuts  2  to roll downward and the cracking zone  15  is decreased, resulting in increasing pressure applied to the nuts  2  as they are squeezed between the textured exterior surface  22  and textured interior surface  42 . 
   If either the textured exterior surface  22  or the textured interior surface  42  were smooth, then the nuts  2  would slip and move upward, never breaking or cracking. This is why tread plate is used to grip the nuts—its elongated protrusions  41  which protrude no more than one-eighth of an inch and are at right angles to each other woven into a pattern at regular intervals, cause consistent gripping and cracking of the nuts because of the even distribution of pressure, but not tearing into the shells and creating small pieces which must be cleaned. 
   If the angle  90  were too great, then the nuts  2  would also slip and move upward, never breaking or cracking. However, if the angle  90  were two small, then the nuts  2  would be crushed and broken repeatedly as the pressure was applied over a greater distance, causing them to break into many small pieces. The inventor has found that an angle  90  between six and ten degrees, and preferably eight degrees, and a minimum cracking zone width M between the bottom part of the textured exterior surface  22  and textured interior surface  42  of three-eighths of an inch to five-eighths of an inch, and preferably seven-sixteenths to one-half of an inch, allows the nutcracker  10  to crack any type of nuts  2  except peanuts. No adjustment of the nutcracker  10  is needed to crack different types of nuts  2 . 
   When the nuts  2  are poured between the vertical cylinder  40  and the conical member  20  and the conical member is rotated, the nuts  2  move downward, the shells of the nuts crack, and the nuts break into halves and thirds, fall onto the first plate  54 , and slide out of the nutcracker  10  along the spout  46 , as shown in  FIG. 9 . Walnuts begin cracking when they are about half-way down from the top of the conical member  20 , and are usually cracked by the time they are two inches down from this half-way point. It has been found that 216 pounds of walnuts per hour, or one bushel of walnuts every ten minutes, can be cracked by hand using the embodiment described herein. 
   Although this invention has been described above with reference to particular means, materials and embodiments, it is to be understood that the invention is not limited to these disclosed particulars, but extends instead to all equivalents within the scope of the following claims.