Abstract:
A high production nutcracking apparatus wherein any whole nuts which are mis-fed or fail to be cracked, are automatically returned to the feed hopper without being exposed to possible contamination. To separate the shell fragments from the uncracked whole nuts, there is provided an inclined openwork grate, which is sized and configured to permit the shell fragments to pass directly therethrough while the whole nuts slide down and drop off a lower end of the grate. The grate is formed of a plurality of parallel rods which are supported so that they vibrate during operation of the cracking apparatus, to facilitate the sliding movement of the whole nuts.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to a high speed nutcracking apparatus having provision for effectively separating shell fragments from uncracked whole nuts, and which serves to recycle the uncracked whole nuts back into the apparatus while maintaining the nuts in a clean and sterile condition. 
   U.S. Pat. Nos. 4,332,827; 5,623,867; 6,205,915; 6,270,824; 6,584,890, 6,588,328; and 6,772,680 all disclose a high speed nutcracking apparatus which includes a rotatable turret which mounts a plurality of cracking units arranged about is periphery, with each cracking unit having an opening adapted to receive an individual nut from a feed conveyor which comprises a plurality of nut transport elements mounted in succession on a feed chain. Each of the nut transport elements includes an upwardly open traverse receptacle for holding an individual nut, and each cracking unit on the turret has an anvil which is moved axially into the receptacle at a pick up point so that the nut is engaged between the anvil and a crack die on the other side of the opening. 
   In operation, the feed conveyor moves tangentially past the rotating turret so that the anvils of the cracking units enter the receptacles of respective nut transport elements at the pick up point and engage and pick up the nut. After the cracking unit and engaged nut have moved away from the pick up point and reach a cracking location, the crack die of the cracking unit is impacted by a shuttle so that the crack die applies an impact to the nut to crack the shell. 
   To facilitate the cracking operation, and to sanitize the nuts, the nuts are typically soaked in hot water prior to the cracking operation. However, maintenance of the sanitized conditions has not always been achieved, by reason of two factors. First is the fact that contamination of the nuts can occur through contact with the oil used in the lubrication system of the machine. This problem has been effectively alleviated by the sealed lubrication system described in U.S. Pat. No. 6,772,680. 
   The second factor which has contributed to the loss of sanitized conditions is the fact that the machine operators are often lax in assuring proper procedures are maintained during the operation of the machine. In particular, the machines will inherently mis-feed a small number of nuts prior to reaching the pick up point on the turret, and a few nuts will be dropped by the turret prior to being cracked, and these uncracked whole nuts fall to the ground, where they may come in contact with oil or other contaminants. The machine operators are instructed to return the nuts to the sanitizing water bath, but they will often simply shovel the contaminated nuts back into the feed hopper. 
   It is accordingly an object of the present invention to provide a nutcracking apparatus of the described type which is capable of separating the uncracked whole nuts from shell fragments generated during the cracking operation, and returning the separated whole nuts to the feed hopper while assuring that they are maintained in a clean and sterile condition. 
   SUMMARY OF THE INVENTION 
   The above and other objects and advantages of the invention are achieved by the provision of a high production nutcracking apparatus of the described type which includes guide means for delivering at least some of the shell fragments which are produced at the cracking location, and any whole nuts which are mis-fed or fail to be cracked, from the cracking turret and onto an inclined openwork grate. The inclined grate is configured to permit the shell fragments to pass directly therethrough while the whole nuts slide down and drop off a lower end of the grate, to thereby separate the shell fragments from the uncracked whole nuts. 
   The apparatus of the invention preferably also includes a nut return system for automatically returning to the hopper the uncracked whole nuts which drop from the lower end of the grate. Thus the uncracked whole nuts are returned to the hopper without exposure to possible contamination. 
   To facilitate the removal and collection of the shell fragments, a chamber is provided which substantially encloses the cracking location, and a vacuum aspiration system is provided to deliver the collected shell fragments to a waste container. To collect those shell fragments which are not collected by the aspiration system described above and which fall through the grate, there is provided a second aspiration system for collecting and delivering those shell fragments to the same or different waste container. 
   The grate of the present invention preferably comprises a plurality of parallel rods with the rods being laterally aligned in a common plane and laterally spaced apart a predetermined distance which is correlated to the size of the nuts being cracked. Also, the grate is supported only adjacent the upper ends of the rods, so that the rods vibrate by the operation of the machine to thereby assist movement of the whole nuts toward the lower end of the grate. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
       FIG. 1  is a perspective view of a high production nutcracking apparatus which embodies the features of the present invention; 
       FIG. 2  is a front elevation view of the apparatus, with the front doors and hood being opened; 
       FIG. 3  is a sectional side elevation view taken along the line  3 — 3  of  FIG. 2 ; 
       FIG. 4  is a sectional front view taken along the line  4 — 4  of  FIG. 3 ; 
       FIG. 5  is a perspective view of the nozzle which forms a part of the air ejection system; 
       FIG. 6  is a top plan view of the grate which forms a part of the system for separating the loose shell fragments from the uncracked whole nuts; 
       FIG. 7  is a sectional side elevation view which is taken along the line  7 — 7  of  FIG. 4 ; and 
       FIG. 8  is a fragmentary view of the air aspiration systems of the apparatus. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which a preferred, but not necessarily all embodiments of the invention is shown. Indeed, the invention may be embodied in many different forms and should not be construed as limited to the embodiment set forth herein. Rather, the illustrated embodiment is provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. 
   Referring more particularly to the drawings,  FIGS. 1–8  illustrate a high production nutcracking apparatus  10  which embodies the features of the present invention. As will become apparent, many of the components of the present apparatus conform to the corresponding components of the apparatus shown and described in the prior U.S. patents which are listed above under the heading Background of the Invention. The disclosures of these prior patents are expressly incorporated herein, and reference may be had to these prior patents for a more detailed description of the common components. 
   The apparatus comprises a frame which defines a box-like cabinet  12  which includes a pair of front doors  13 ,  14 , and a rear side  15 . A hood  16  is pivotally mounted to the top of the cabinet and so as to be pivotable between a closed position ( FIGS. 1 and 3 ) and an open position ( FIG. 2 ). Also, the upper edge of the cabinet  12  supports a pair of bearing blocks  17 ,  18  which rotatably mount a central shaft  19  which defines a horizontal central axis. 
   A cracking assembly in the form of a turret  20  is fixedly mounted to the shaft  19  so as to be rotatable with the shaft about the central axis. The turret  20  comprises a plurality of elongate cracking units  22  which are circularly arranged about the shaft and supported by radially disposed plates (not shown). There are sixteen cracking units in the illustrated embodiment and the units extend generally parallel to each other and to the central axis. 
   The cracking units  22  each define an opening for receiving the nuts, and the openings of the units are aligned with an annular opening  24  in the periphery of the turret as best seen in  FIG. 2 . The structure and function of the cracking units are otherwise fully disclosed in the prior patents listed above and which are incorporated by reference. 
   The apparatus of the present invention further includes means for advancing and delivering a plurality of nuts individually in succession along a path of travel to the rotating turret  20 . This nut delivering means includes a hopper  26  for storing a relatively large quantity of nuts to be cracked, and which is fixed to the rear side  15  of the cabinet  12 . An endless feed conveyor  28  is provided which includes a feed chain which extends through the hopper and conveys the nuts to a delivery point adjacent the bottom dead center position of the turret  20 , all as further described in the prior patents which are incorporated by reference. 
   The turret  20  is rotatably driven by a motor and chain drive  30  ( FIGS. 2 and 3 ) and operates so that each cracking unit  22  picks up a nut from the conveyor  28  at the bottom dead center position of the turret. With continued rotation of the turret, the nut is stressed at about the 11 o&#39;clock position of the turret when viewed as seen in  FIG. 3  and with the turret rotating in the counterclockwise direction. Immediately thereafter, the nut is cracked, and the cracked nut falls into a delivery chute  32  which exits on the side of the cabinet, note  FIG. 4 . 
   The cracking of the nuts at the cracking location will inherently produce a quantity of loose shell fragments. To collect these loose shell fragments, the present invention incorporates two air aspiration systems which collect and deliver the fragments to a waste container. 
   The first or upper aspiration system  34  comprises a sealing arrangement which encloses the cracking location so as to form a chamber which substantially encloses the cracking location and which communicates with an exhaust duct  35  connected to the hood  16  of the apparatus. The exhaust duct  35  is in turn connected to a collection chamber  36  and vacuum source  37 . The collection chamber includes a conventional cyclone separator  38  for separating the fragments from the airstream, and a rotatable gate  39  which allows passage of the fragments while sealing against the passage of air. 
   The sealing arrangement comprises a pair of annular brushes  40 ,  41  which encompass the turret on respective opposite sides of the annular opening  24  which receives the nuts. About one half of each annular brush is mounted to the frame of the cabinet  12 , and the other half is mounted to the hood  16 , note  FIG. 7 . 
   The hood  16  also mounts a pair of flaps  42 ,  43  which extend substantially between the brushes and ride on the turret so as to partially fall into the opening  24 , note  FIG. 3 . The flaps  42 ,  43  are positioned so that one flap  42  overlies the turret upstream of the cracking location and the second flap  43  overlies the turret downstream of the slot. The exhaust duct  35  is connected between the flaps. 
   The flaps and annular brushes obviously are not able to form a perfect seal, but they nevertheless serve to retain a significant portion of the loose shell fragments so that they can be removed through the exhaust duct  35 . Those loose shell fragments that are not collected by the first aspiration system  34  fall downwardly through the turret. To collect these fragments, a second or lower aspiration system  45  is provided, which includes a pair of side plates  47 ,  48  (note  FIG. 4 ) which are parallel to each other and extend vertically on respective opposite sides of the opening  24  and the conveyor  28  to define a downwardly directed guide passage  50  for the falling fragments. The guide passage is also closed by the front doors  13 ,  14  and the rear side  15  of the cabinet through which the feed conveyor  28  enters and leaves the cabinet  12 . 
   An inclined solid guide plate  52  is positioned to extend between the side plates  47 ,  48  and rearwardly from the front of the cabinet to about the midportion thereof. Thus the guide plate  52  closes the bottom of the front portion of the guide passage  50 . 
   A collection chute  54  underlies the rear portion of the guide passage  50 , and the collection chute  51  extends forwardly from the rear side  15  of the cabinet a distance sufficient to extend somewhat beyond the lower edge of the guide plate  52 . Thus the loose shell fragments which are not collected by the first aspiration system  34  fall either directly into the chute  54 , or onto the guide plate  52  and then into the chute  54 . The chute is connected to an exhaust duct  55 , which leads to the collection chamber  36 , note  FIG. 8 . 
   A grate  56  is positioned between the lower end of the guide plate  52  and the chute, which is configured to allow the shell fragments to freely pass therethrough. As best seen in  FIG. 3 , the grate extends from a point adjacent the rear side  15  of the cabinet to a point beyond the lower end of the guide plate  52 . Also, it is inclined in a direction opposite to the inclination of the guide plate  52 . 
   Any uncracked whole nuts which are mis-fed by the conveyor, or which are dropped or fail to be cracked by the turret, drop downwardly through the guide passage  50  in the cabinet and fall either directly onto the grate  56  or onto the guide plate  52  and then onto the grate  56 . Thus both the loose shell fragments and the uncracked whole nuts both fall onto the grate  56 , and the grate is configured to separate the whole nuts from the fragments. More particularly, the grate comprises an open-work structure composed of a plurality of parallel rods  58  which extend from an upper end adjacent the rear side  15  of the cabinet to the opposite lower end. The rods  58  are laterally aligned in a common plane and laterally spaced apart a predetermined distance which is correlated to the size of the nuts being cracked. Thus when the shell fragments and whole nuts are delivered onto the grate  56 , the fragments fall directly through the grate and into the chute  54 , and the whole nuts slide to the lower end of the grate  56  and fall off into a separate chute  60  which is located adjacent the front of the cabinet. 
   The rods  58  of the grate  56  are interconnected by a single cross bar  61  at the upper end of the grate, and the cross bar is supported in the cabinet so that the grate can be easily removed and replaced with a grate of different lateral spacing so as to function with nuts of a different average size. More particularly, the cross bar  61  is secured between the side plates  47 ,  48  by releasable locking members  62  as seen in  FIG. 6 , and the outermost rods  58  are received in sleeves  63  which are secured to the side plates. As a result of this construction and mounting arrangement, the lower end portion of all but the two outermost rods are free to vibrate from the operation of the cracking machine, and this vibration has been found to assist in the sliding movement of the whole nuts toward the lower end of the grate  56  and into the chute  60 . 
   The apparatus of the present invention further comprises a nut return system for receiving the whole nuts which drop from the lower end of the grate  56  into the chute  60 , and for delivering the received nuts back into the hopper  26 . The nut return system includes the chute  60 , and a receptacle  66  located at the bottom of the chute  60 , note  FIG. 4 . A nut return line  67  communicates with one side of the receptacle  66 . 
   The nut return system further includes an air ejection system for ejecting each nut received in the receptacle  66 . The air ejection system includes a sensor  68  which is provided in the bottom of the receptacle and which is designed to sense the presence of a nut. The sensor  68  may for example comprise Allen Bradley capacitive proximity sensor. Also, the air ejection system includes a source of pressurized air which is connected to a delivery line  70  which communicates with an air nozzle  72  which is positioned opposite the nut return line  67  so that air injected through the outlet of the nozzle blows across the receptacle and into the nut return line  67 . An electronic air valve  73  is positioned in the delivery line  70 , and the valve  73  is controlled to cause the valve to open for a predetermined computer controlled time, such as five seconds, in response to a signal from the sensor  68 . Thus in operation, the sensor  68  senses whenever a whole nut is received in the receptacle  66 , and the valve  73  opens to inject a blast of air from the nozzle and into the receptacle to eject the nut from the receptacle and into and through the nut return line  67 . 
   As will be understood by those skilled in the art, the injected air stream may cause the nut to be drawn toward the outlet of the nozzle  72  by reason of the Bernoulli effect. When this happens, the nut remains in the receptacle and is not ejected into the delivery line  70 . To preclude this possibility, a post  75  is mounted in the receptacle, e.g. on the front face of the nozzle  72 , to hold the nut at a distance from the outlet of the nozzle and so that the nuts will be consistently ejected from the receptacle. 
   The nut return line  67  includes a rigid delivery tube  76  which extends into the hopper and which opens at a location which can be below the normal height of the nuts in the hopper. 
   Many modifications and other embodiments of the invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiment disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.