Abstract:
A high production nutcracking apparatus wherein the nuts are fed from a hopper on a feed conveyor to a cracking apparatus. The cracking apparatus is in the form of a plurality of cracking units mounted on a rotatable turret, and the rotating cracking units are cyclically controlled so as to clampingly engage and lift each oriented nut from the advancing conveyor, and so as to preserve its orientation. Each nut is then cracked and thereafter released at separate spaced points along the circular path of travel of the cracking unit. A structure and procedure for aligning the cracking units of the turret with respect to the feed conveyor is disclosed.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to an improved high production nutcracking apparatus, and more particularly, to a nutcracking apparatus of the type disclosed for example in U.S. Pat. No. 5,623,867 and application Ser. No. 09/638,423 filed Aug. 14, 2000, now U.S. Pat. No. 6,205,915 and which has an improved capability of aligning its components. 
     The nutcracking apparatus as disclosed in the above patent and application includes a rotatable turret which mounts a plurality of cracking units arranged about its periphery, with each cracking unit having an opening adapted to receive an individual nut from a nut 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 transverse 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 pickup 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 tangentally past the rotating turret so that the anvils of the cracking units enter the receptacles of respective nut transport elements at the pickup point and engage and pick up the nut. After the cracking unit and engaged nut have moved away from the pickup point, the crack die of the cracking unit applies an impact to the nut to crack the shell. 
     To insure proper engagement of the nut, and to avoid damage to the components of the machine, it is important that the cracking units be properly aligned and timed with respect to the receptacles of the nut transport elements. Heretofore, the alignment and timing operation was carried out by manually releasing the drive of the turret so that it could be rotated without causing the feed conveyor to advance, and the turret was then rotated until the operator believed the anvil of a cracking unit was in its bottom dead center position and centered in a receptacle. This procedure was unsatisfactory however, since the covers and other components of the apparatus rendered it very difficult if not impossible to see the anvil of the lowermost cracking unit when it is located in the receptacle. Thus, proper alignment was not assured. 
     It is accordingly an object of the present invention to provide a high production nutcracking apparatus of the described type and which has provision for a simple and reliable alignment of the cracking units with respect to the receptacles of the nut transport elements. 
     SUMMARY OF THE INVENTION 
     The above and other objects and advantage of the present invention are achieved by the provision of a high production nutcracking apparatus which comprises a turret mounted on a machine frame for rotation about a horizontal central axis, with the turret mounting a plurality of cracking units which are uniformly spaced about the periphery of the turret. An endless feed conveyor is provided which is composed of a plurality of nut transport elements mounted in succession along a feed chain, with each element including a generally semi-cylindrical receptacle which extends laterally across the element. The feed conveyor is mounted to the machine frame so as to define an upper run which extends generally tangentially with the periphery of the turret and to define a pickup point where the upper run perpendicularly intersects a radius of the turret. A drive system is provided for concurrently rotating the turret about the central axis and advancing the feed conveyor such that the cracking units are aligned with the receptacles of respective nut transport elements at the pickup point, and the drive system includes a releasable interconnection for permitting relative movement between the turret and feed conveyor at the pickup point. An indicator and locking device is mounted on the turret and the machine frame for indicating when the turret is rotated to a point wherein one of said cracking units is in a bottom dead center position with respect to the pickup point and for locking the turret against rotation in such position. 
     With the nutcracking apparatus as described above, the cracking units of the turret may be aligned with the receptacles of the nut transport elements by rotating the turret to an aligned position wherein one of the cracking units is in the bottom dead center position, and then moving the feed conveyor while the turret is stationary in the aligning position until the receptacle of one of the nut transport elements is centered in radial alignment with the one cracking unit which is in the bottom dead center position. 
     More particularly, the alignment procedure includes the steps of disengaging the interconnection of the drive system, rotating the turret to the aligned position wherein one of the cracking units is in a bottom dead center position with respect to the pickup point, then moving the feed conveyor while the turret is held stationary until the receptacle of one of the nut transport elements is centered in radial alignment with the cracking unit which is in the bottom dead center position, and then re-engaging the interconnection of the drive system. The apparatus is then in condition for normal, high speed operation, with a precise alignment of the nut cracking units with the receptacles of the nut transport elements being assured. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Some of the objects and advantages of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which: 
     FIG. 1 is a perspective view of a nutcracking apparatus which embodies the features of the present invention; 
     FIG. 2 is a fragmentary perspective view of the front end of the apparatus taken along the line  2 — 2  of FIG. 1; 
     FIG. 3 is a fragmentary sectional view taken along the line  3 — 3  of FIG.  2  and illustrating the indicator and locking device of the present invention, with the locking pin of the device in its storage position; 
     FIG. 4 is a fragmentary sectional side elevation view taken substantially along the line  4 — 4  of FIG. 1; 
     FIG. 5 is a fragmentary sectional view of the turret taken along the line  5 — 5  of FIG. 4, and illustrating two of the cracking units; 
     FIG. 6 is a view similar to FIG.  3  and illustrating the locking pin in its operative position; 
     FIG. 7 is a cross sectional view of the releasable drive sprocket for the feed conveyor; 
     FIG. 8A is a fragmentary sectional view illustrating the turret and feed conveyor in a first position of the alignment procedure; 
     FIG. 8B is similar to FIG.  8 A and illustrating a second position of the alignment procedure; and 
     FIG. 8C is similar to FIGS. 8A and 8B and illustrating the final position of the alignment procedure and wherein the lowermost cracking unit is aligned in the receptacle of the associated nut transport element. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring more specifically to the drawings, a nutcracking apparatus embodying the features of the present invention is illustrated generally at  10  in FIG.  1 . The apparatus includes a rectangular box-like frame  12  which supports a pair of bearing blocks  14  (note FIG. 5) which rotatably mount a central shaft  20  which defines a horizontal central axis. 
     As best seen in FIG. 5, a turret  22  is fixedly mounted to the shaft  20  so as to be rotatable with the shaft about the central axis. The turret  22  comprises a plurality of elongate cracking units  24  which are circularly arranged about the shaft and supported by the end plates  25  and  26 , and the intermediate plates  27 ,  28  and  29 . The frame  12  includes a front plate  15  and a cover  16  which is mounted to the front plate and overlies the end plate  26 . A felt pad  17  is disposed between the end plate  26  and the cover so as to facilitate relative rotation while maintaining air seals in the manner which will become apparent. 
     There are sixteen cracking units  24  in the illustrated embodiment and the units extend generally parallel to each other and to the central axis. Each of the cracking units  24  comprises an anvil  32 , a cracking die assembly  34  which includes a cracking die  35 . The anvil and cracking die assembly are mounted in an axially aligned, opposed relationship to define an opening for receiving a nut N therebetween. More particularly, the means for mounting the anvil  32  includes a first air cylinder  37 , a piston  38  slidably disposed within the cylinder  37 , a piston rod  39  interconnecting the piston and anvil, a first air port  40  disposed adjacent the rearward end of the cylinder, and a second air port  42  disposed adjacent the forward end of the cylinder. As will be apparent, movement of the piston  38  results in a corresponding movement of the anvil  32 , either forwardly toward the cracking die assembly  34  or rearwardly therefrom. Such movement is controlled by air which is selectively provided to the first and second ports  40 ,  42  in a manner more fully disclosed in U.S. Pat. Nos. 4,418,617 and 4,441,414, the disclosures of which are expressly incorporated herein by reference. 
     The cracking die assembly  34  is more fully described in the above referenced &#39;414 patent, and in copending U.S. patent application Ser. No. 09/592,245, filed Jun. 13, 2000, and it includes the cracking die  35 , and a second air cylinder  44 . A free floating shuttle  46  is mounted within the cylinder  44 . In addition, there is provided an air port  47  adjacent the forward end of the cylinder and a further port  48  which extends axially through the rearward end of the cylinder. 
     The control system for cyclically actuating the cracking unit includes an air control system whereby air is selectively introduced into the four ports  40 ,  42 ,  47 , and  48 . More particularly, upon receiving a nut N in the opening between the anvil  32  and cracking die assembly  34 , air is first introduced into the port  40  so that the piston  38  and anvil  32  are moved forwardly and such that the anvil  32  operatively engages one end of the nut N in the opening. The nut thereby becomes supported between the anvil  32  and cracking die  35 . The anvil  32  and cracking die  35  thereby also serve to compressively stress the retained nut. High pressure air is next injected through the port  48  and into the air cylinder  44 , such that the shuttle  46  is thrust forwardly along the cylinder and impacts against the rear end surface of the cracking die  35 , causing the cracking die to sharply advance a short distance forwardly against the nut and thereby crack its shell. The air in front of the advancing shuttle is permitted to exhaust through the port  47 . Air next enters the port  42 , causing the piston  38  and anvil  32  to move rearwardly and release the nut, and as a final step, air is caused to enter the port  47  and thereby return the shuttle  46  to its rearward position. The apparatus is then in position to receive another nut to be cracked, with the above cycle being cyclically repeated. Further details regarding the air control system for cyclically actuating the apparatus  10  may be obtained from the above noted prior patents. 
     The apparatus of the present invention further includes an apparatus  50  for advancing and delivering a plurality of nuts individually in succession along a path of travel to the rotating turret  22 . This nut delivering apparatus includes a hopper  55  for storing a relatively large quantity of the nuts to be cracked, and an endless feed conveyor  56  which includes a feed chain  57  (FIG. 5) and a pair of supporting sprockets  58 ,  59  mounted respectively on the shafts  60 ,  61 , which support the feed chain. The feed chain is also supported by a third sprocket (not shown) which is located below the hopper. 
     The feed conveyor  56  is mounted for movement about the sprockets  58 ,  59 , and includes an upper run which extends through the lower portion of the hopper  55  and along a path of travel which includes an upwardly inclined segment  56   a  extending through the lower portion of the hopper, and a substantially horizontal segment  56   b  extending from the upwardly inclined segment to the sprocket  59 . The upper run extends generally tangentially with the periphery of the turret and it defines a nut pickup point where the upper run perpendicularly intersects a vertical radius of the turret. 
     A plurality of block-like nut transport elements  65  are mounted in succession along the feed chain  57 . As best seen in FIGS. 4 and 5, and as further illustrated in U.S. Pat. No. 5,623,867, each element  65  includes parallel opposite sides, parallel opposite ends, and top and bottom faces (not numbered). A generally semi-cylindrical receptacle  70  extends laterally across the upper face of the element, and so as to communicate with both sides thereof. By design, each receptacle  70  is sized to supportingly receive a single nut to be cracked which is oriented with its end to end direction extending axially along the receptacle. Each element  65  further includes a longitudinal channel in the bottom face for receiving the feed chain  57 , and a pair of transverse pins (shown in dashed lines in FIG. 5) for interconnecting the element to the chain. 
     While in the illustrated embodiment, the segment  56   b  of the feed conveyor  56  is horizontal, it will be appreciated that the segment  56   b  could be positioned at an angle with respect to the horizontal so as to tangentially engage the periphery of the turret at a location spaced from its lowermost point. In any event however, the upper run extends tangentially with respect to the periphery of the turret and it defines a nut pickup point where the upper run perpendicularly intersects a radius of the turret. 
     The conveyor  56  is powered by the motor  80  and drive chain  82 , which drives the sprocket  59  and which also drives the turret  22  in the manner seen in FIG. 4, and such that the transport elements and thus the nuts move from the hopper tangentially past the circle defined by the rotating cracking units  24 , at a speed corresponding to such rotational speed. More particularly, the drive chain  82  drives a sprocket  83  which is fixed to the drive shaft  61 , and a keyless bushing  84  as shown in FIGS. 5 and 7 releasably connects the shaft  61  and the sprocket  59  of the drive chain. The keyless bushing  84  is of conventional design and it incorporates a nut  85  which upon rotation serves to lock and unlock the sprocket  59  to the shaft  61 . A keyless bushing of this type is further described in U.S. Pat. No. 5,695,297, the disclosure of which is incorporated by reference. 
     The hopper  55  includes singularizing and orienting means to ensure that any nuts in excess of one are removed from the receptacle  70  of each nut transport element  65 , and that each nut is oriented with its end to end direction extending axially along the receptacle  70 . This singularizing and orienting means includes a deflecting plate  90  which is further described in U.S. Pat. No. 5,623,867 and copending application Ser. No. 09/638,423, the disclosures of which are incorporated by reference. 
     As the nut transport elements advance along the horizontal segment  56   b  toward and under the pickup point, they are supported by a support plate  92  which is adjustable in elevation with respect to the cracking units in the turret. A further description of the support plate  92  and its mounting structure, may be found in copending application Ser. No. 09/638,423. 
     To describe the operation of the apparatus in more detail, it will be understood that the motor  80  acts to rotate the turret  22  about the central axis of the shaft  20 , and to advance the conveyor  56  so that the upper run moves toward the turret at a speed corresponding to the rotational speed of the cracking units  24 . The nut transport elements  65  thereby move in succession through the hopper  55 , and the nuts therein are received in the receptacles  70 , and singularized and oriented by contact with the plate  90 , in the manner described above. The nuts are thereby effectively individually received in the respective receptacles  70 , and oriented with their end to end direction being disposed horizontally and perpendicular to the direction of movement of the upper run of the conveyor. 
     By design, the nuts are moved in succession to the openings between the anvil  32  and cracking die assembly  34  of a cracking unit  24  as the cracking unit passes a nut delivery or pickup point, which is located at about the bottom dead center of the circle defined by the rotating cracking units. By adjustment of the elevation of the support plate  92 , the centerline of the nuts being processed can be accurately aligned with the axis along which the anvil and cracking die are moved. At this point, pressurized air is directed to the first port  40  of the cracking unit. The piston  38  and anvil  32  are thereby moved forwardly, and such that the anvil operatively engages one end of the nut N in the opening, and with the force acting through the nut to clampingly engage and retain the nut in an end to end alignment between the anvil  32  and the cracking die  35  of the die assembly  34 . The nut is thereby lifted from its receptacle on the feed conveyor  56 . The frictional contact between the piston  38  and the walls of the air cylinder  37  serves to maintain the forward axial position of the anvil during rotational movement of the cracking unit upwardly and away from the conveyor. 
     The nut is then advanced along a curvilinear path of travel, i.e., the circle defined by the rotating cracking units  24 , and to a nut stressing location, which is located about 60 degrees beyond the bottom dead center position. At this location, air again enters the first port  40  to compressively stress the retained nut. Immediately thereafter, high pressure air is injected into the port  48  of the air cylinder  44 , such that the shuttle  46  is thrust forwardly along the cylinder  44  and impacts against the rear side of the cracking die  35 , causing the cracking die to sharply advance a short distance forwardly and thereby crack the nut. The air in front of the advancing shuttle exhausts through the port  47 , which is of relatively large diameter to accommodate the entering air without an undue build-up of pressure. Most of the loose shell fragments resulting from the cracking operation are drawn off through a housing by a vacuum line (not shown). Further, the cracking operation preferably occurs while the nut remains under compressive stress. 
     The cracked nut remains supported between the anvil and cracking die after the cracking operation, and is carried to a release point, which is preferably positioned at about 45 degrees beyond the top dead center position of the turret. At this point, air enters the second port  42 , and the piston and anvil are moved rearwardly. The released nut then falls to the laterally directed discharged chute  94  (FIG.  4 ). 
     As the final step, air is caused to enter the port  47 , and the shuttle  46  to return to its rearward position. The cycle may then be repeated as the cracking units move through the loading position to receive another nut from an aligned receptacle. 
     As will be apparent, it is important that the cracking units  24  of the turret  22  be precisely aligned with nut transport elements  65  so that the anvil  32  of each cracking unit enters the receptacle of the associated nut transport element at the midpoint of the longitudinal width of the receptacle. If misalignment is present, the anvil may engage the side of the element  65 , or it may enter the receptacle but not engage the centerline of the nut, thereby causing the nut to be deflected and not picked up. 
     To permit the alignment procedure of the present invention to proceed in the manner further described below, the apparatus incorporates an indicator and locking device  95  which is mounted on the turret  22  and the machine frame  12  for indicating when the turret is rotated to a point wherein one of the cracking units is in a bottom dead center position with respect to the pickup point. The turret may then be locked at such point. 
     The indicator and locking device  95  includes four openings  96  in the end plate  26  of the turret, note FIG. 4, with the openings  96  being equally spaced in the circumferential direction and so that each opening  96  is positioned in a predetermined location with respect to the cracking units. The front plate  15  of the frame includes a bore  98  which extends through the cover  16  and is radially spaced so as to communicate with the openings  96  as the turret rotates. By design, when the bore  98  is aligned with any one of the openings  96  in the end plate  26 , one of the cracking units  24  is positioned at the desired bottom dead center position. The number of openings  96  in the end plate  26  is arbitrary, and only one is required for the alignment procedure as described below to be carried out. However, the presence of a plurality of openings  96 , any one of which is useable, facilitates the procedure as will become apparent. 
     The indicator and locking device  95  further includes a pin  100  which is removably mounted in the bore  98  in the frame so that the pin may enter any one of the openings  96  in the end plate when one of the cracking units is in the bottom dead center position. The turret is then locked against further rotation, note FIG.  6 . The inner end of each opening  96  may be closed to prevent oil and debris from entering into the turret. 
     The bore  98  in the frame is defined by a bushing  102  which is bolted to the frame, and the outer end position of the bore  98  in the bushing  102  is internally threaded. The pin  100  has one end  104  which is of a size and length to extend through the bore  98  in the bushing  102  and into the opening  96  of the end plate of the turret. The medial portion of the pin  100  mounts a knurled hand grip  105  and the opposite end  106  is externally threaded so as to permit the threaded opposite end of the pin to be threadedly received in the threaded portion of the bore  98  in the bushing to define a storage position wherein the pin does not engage an opening  96  in the end plate. This storage position is illustrated in FIG. 3, and prevents the pin from being inadvertently misplaced and lost. 
     In accordance with the present invention, the required precise alignment of the apparatus is achieved by the following steps: 
     1. The locked connection of the keyless bushing  84  is released by rotation of the nut  85  so that the sprocket  59  is free to rotate relative to the shaft  61  and thus the turret. 
     2. The turret is manually rotated until the bore  98  in the bushing  102  is aligned with the nearest one of the openings  96  in the end plate  26 , thereby indicating that one of the cracking units  24  is in a bottom dead center position with respect to the feed conveyor. The anvil  32  of the one cracking unit will be concurrently extended by air entering through the port  40 . 
     3. The pin  100  is inserted through the bore  98  and into the aligned opening  96  to lock the turret in an aligned position. 
     4. The feed conveyor  56  is moved by hand in a rearward direction until the extended anvil engages the front wall of the receptacle  70 , note FIG. 8A, and the position of a reference point (e.g. an end wall of one of the elements  65 ) on the feed conveyor is recorded by a mark at A on a reference member (e.g. a sheet of paper) which is temporarily mounted to the frame. 
     5. The feed conveyor  56  is moved in a forward direction until the extended anvil engages the rear wall of the receptacle and the reference point on the feed conveyor is recorded by a mark at B on the reference member. 
     6. The feed conveyor  56  is moved rearwardly until the reference point is midway between the marks A and B, i.e. at C, which conforms to the desired alignment position. 
     7. The keyless bushing  84  is tightened by rotation of the nut  85  to lock the sprocket  59  to the shaft  61 . 
     8. The pin  100  is removed and repositioned to its storage position as seen in FIG.  3 . The machine is then aligned and ready for normal operation. 
     In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.