Abstract:
An apparatus which automatically forces open shells during the downward stroke of a reciprocating plunger. Opening can occur through shearing of the two shell halves along their seam. The tip of the plunger can be a long inclined blade and wedge shaped. The apparatus may open all sizes of shells by applying a downward force on at least one of the shell halves. Alternatively, both shearing and sliding forces are applied. In one embodiment the shell is placed parallel to the angle of taper of the tip for opening. When the plunger comes down it exerts by frictional shearing force on the shell which causes the halves to slide off each other and open providing access to the inside.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation-in-part of co-pending U.S. patent application Ser. No. 11/186,017, filed Jul. 20, 2005, which is incorporated herein by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     REFERENCE TO A “MICROFICHE APPENDIX” 
     Not applicable 
     BACKGROUND 
     The present invention generally relates to seafood peeling and opening. More particularly, the present invention relates to a method and apparatus for automatically opening shells. 
     Manually opening shells, such as oyster shells, requires much time and effort. It would be advantageous to provide a method and apparatus for automatically opening shells. 
     SUMMARY 
     In one embodiment the method and apparatus automatically opens two halves of oyster shells without using a hand hammer to breaks or crack open the shells. 
     In one embodiment the opening of oyster shells can be assisted by an operator of the apparatus, such as by aligning the shells to be opened under a reciprocating plunger. In one embodiment the operator manually cuts out the oyster from the opened shell. 
     In one embodiment an individual holds an unopened oyster shell under the press while a plunger moves down, the plunger contacts the shell, and the shell is opened by the downward movement of the press. 
     In one embodiment the halves of the oyster shells are opened by shearing. In one embodiment the halves of the oyster shells are opened by chiseling. 
     In one embodiment the method and apparatus automatically opens multiple oyster shells each minute. In one embodiment this process is repeated at least 40 times a minute. In one embodiment this process is repeated at between at least 40 to 60 times a minute. In one embodiment this process is repeated at least 60 times a minute. In one embodiment this process is repeated between 60 and 175 times a minute. 
     In one embodiment, after the shell is opened, an individual cuts out the oyster from the opened half shells. 
     In one embodiment the apparatus is powered by an electrical motor. In one embodiment the motor can include a speed control, such as a digital speed control. 
     In one embodiment the apparatus includes a linkage system, operably connected to a reciprocating plunger, and powered by a motor. In one embodiment the operable connection includes a gear reducer and a linkage system (e.g., a four bar linkage system). The four bar linkage system can be operably connected to a rack system which itself is operably connected to a plunger. 
     In one embodiment one of the bars of the four bar linkage system is connected to the rack system and this bar is caused to reciprocate back and forth thereby causing the press to reciprocate up and down. 
     In one embodiment the apparatus applies force on the plunger and tip to contact and separate oyster shells into their component halves. This separation can be accomplished by shearing the two half shells apart from each other. Alternatively, this separation can be accomplished by chiseling the two half shells apart from each other through the seam between the two halves of the shells. Once the two half shells are separated (e.g., the oyster is opened) the interior of the oyster can be access and cut out with a cutting tools, such as a shucking knife. 
     One embodiment includes an apparatus which automatically forces open shells during the downward stroke of a reciprocating plunger. Opening can occur through shearing of the two shell halves along their seam. The tip of the plunger can be a long inclined blade and wedge shaped. The apparatus may open all sizes of shells by applying a downward force on at least one of the shell halves. Alternatively, both shearing and sliding forces are applied. In one embodiment the shell is placed parallel to the angle of taper of the tip for opening. When the plunger comes down it exerts by frictional shearing force on the shell which causes the halves to slide off each other and open providing access to the inside. 
     In one embodiment the method and apparatus can be used to open and/or crack oyster shells, crab claws, lobster claws, clamshells, etc. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein: 
         FIG. 1  is a perspective view of one embodiment of the apparatus which can be used for opening oyster shells; 
         FIG. 2  is a perspective view of the internal components of the apparatus of  FIG. 1 ; 
         FIG. 3  is a side view schematically illustrating operation of the apparatus of  FIG. 1 ; 
         FIG. 4  is a schematic view of electrical circuit powering the apparatus; 
         FIG. 5  is a sectional view taken along the lines  5 - 5  of  FIG. 2 ; 
         FIG. 6  is a front view of an individual holding a shell to be opened (e.g., looking in the direction of line  5 - 5  of  FIG. 2 ; 
         FIG. 7  is a front view of the shell of  FIG. 6  after it has been opened. 
         FIG. 8  is a side view of  FIG. 6 ; 
         FIG. 9  is a side view of  FIG. 7 ; 
         FIG. 10  is a side view of an alternative apparatus including a double mechanical separator with opposing plungers; and 
         FIG. 11  is a side view of an alternative apparatus including a double mechanical separator with adjacent plungers. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a perspective view of one embodiment of the apparatus  90  which can be used for opening oyster shells  10 . Generally, a plunger  200  reciprocates up and down (as schematically indicated by arrows  354 ). As will be explained below an individual can place an unopened oyster shell  10  on base  110  and under plunger  200 . When plunger  200  comes down it can shear on half of the shell away from the other half shell (along the seam) thereby opening the shell. Once opened the oyster can be removed from the shell (either by the operator or by another individual). The process can be repeated by placing another unopened oyster shell  10 ′ on base  110  and under plunger  200 . By repeated this process oyster shells can be easily opened (and the oyster removed from the shell) without the increased effort required when using manual tools such as hammers and/or shucking knives. 
     Apparatus  90  can be placed on table  750 . Table  750  can include a plurality of legs  760  and a plurality of rollers  770 . Rollers  770  can allow table  750  (and apparatus  90 ) to be easily moved from place to place thus facilitating the portability of apparatus  90 . If desired plurality of rollers  770  can be detachably connectable to plurality of legs  760  so that rollers and be removed (and movement of table  750  can be limited) when table  770  is located at a desired location. Alternatively, one or more of the plurality of rollers  770  can be lockable so that rolling can be prevented (locking rollers are conventionally available). Also alternatively, although not shown, plurality of rollers  770  can be slidably connected to plurality of legs  760  so that when desired plurality of rollers  770  can be slid vertically upward where the bottoms of plurality of legs is lower than the bottom of the plurality of rollers. This can be accomplished by attaching each roller to a collar which collar slides up and down one of the legs (either individually or in combination). Set screws can be used to affix the collars at desired vertical locations. 
     Apparatus  90  can be encased in cabinet  700 . Cabinet  700  can include removable top  710 , plurality of sides  720 , and base  730 . Alternatively, base  730  can be part of table  750 . Base  110  can be a circular disc and connectable to base  730 . Preferably, base  110  is connected by a single fastener in its middle such that base  110  can rotate relative to base  730 . 
       FIG. 2  is a perspective view of the internal components of the apparatus  90 .  FIG. 3  is a side view schematically illustrating operation of apparatus  90 . Generally, apparatus  90  can include a reciprocating plunger  200  driven by motor  650 . Motor  650  can drive plunger  200  by means of gear reducing box  600  and a driving linkage which reciprocatingly drives plunger  200  in press  100 . Motor  650  can be operably connected to gear box  600  through input shaft  610 . Rotation of input shaft  610  causes output shaft  620  to rotate (albeit at a reduced rotation rate depending on the internal gear reduction of gear box  600 ). Output shaft  620  can be used to drive a four bar driving linkage system. 
     The driving linkage can be a four bar linkage system including arm  300 , arm  400 , arm  500 , along with the theoretical bar between arm  500  and  300 . Arm  300  can include first end  310  and second end  320 . First end  310  can be rotationally connected to output shaft  620  pf gear box  600 . Preferably, output shaft  620  is controlled to rotate in the rotational amounts/ranges specified in this application. Alternatively, motor  650  can be directly connected to first end  320 —however, the rotational rates of motors typically are too fast and for the rates of reciprocation desired for plunger  200  and a reduction is desirable (which is obtained by gear box  600 ). Second end  320  is pivotally connected to first end  410  of second arm  400 . Second end  420  of second arm  400  is pivotally connected to first end  510  of third arm  500 . Second end  520  of third arm  500  is rotationally connected to gear  530 . Teeth  540  of gear  530  for a rack and pinion type connection with teeth  220  of plunger  200 . Plunger  200  is slidably connected to press  100  through opening  140 . 
     Motor  650  can cause first arm  300  to rotate (schematically indicated by arrows  350 , although rotation in the opposition direction as arrows  350  will work equally well). Rotation of arm  300  causes an angular reciprocation of arm  500  (as schematically indicated by arrows  352 ). Preferably, arm  500  only reciprocates and does not make complete revolutions—angular reciprocation causes the linear reciprocation of plunger  200 , whereas rotation would eject plunger from opening  140 . 
     In  FIG. 3  H 1  and H 2  indicate the upper and lower heights of plunger tip  230  relative to base  110 . The difference between H 1  and H 2  is the amount of linear reciprocation of plunger  200 . The amount of reciprocation is controllable by many factors such as the diameter of gear  530  (increasing the diameter increases the amount of reciprocation). Additionally, the relative lengths of the four bars also control the amount of angular reciprocation of arm  500  (schematically indicated by arrows  352 )—the larger the amount of angular reciprocation of arm  500  increasing the amount of linear reciprocation of plunger  200 . In this embodiment the length of arm  400  can be adjusted by adjusting members  422  and/or  412 . Similarly, the lengths of arms  300  and  500  can be set up so that they are adjustable. Additionally, the distance between press  100  and gear box  600  can be increased and/or decreased which increases and/or decreases the length of the theoretical fourth bar. H 2  can be set at a desired level by removing plate  140  (through plurality of fasteners  150 ) and setting plunger  200  at the desired linear rotation—at a point when arm  500  is at its maximum extent of angular rotation. 
     Preferably, tip  230  has an upper  232  and lower point  234 , where the upper point  232  is toward the front and higher than the lower point  234 . Also preferably, tip  230  has a V-shape where it increases in width to its top  236 . Also preferably, tip  230  will include at least one discontinuity such as notch  260 . Notch  260  can resist sliding of tip relative to the oyster shell to be opened (during the downward plunging process). 
       FIG. 4  is a schematic view of electrical circuit  91  powering apparatus  90 . Circuit  91  can include motor  650  connected to emergency stop switch  92  (which alternatively can be an on off toggle switch), on off switch  94 , and breaker  96 . A power supply supplies power to circuit  91 . 
       FIG. 5  is a sectional view of base  110  taken along the lines  5 - 5  of  FIG. 2 . Here, base  110  is rotationally connected to base  730  by fastener  112 . It is believe that allowing base  110  to rotate facilitates the opening process of shells  10  when plunger  200  moves downwardly. 
       FIGS. 6 through 9  illustrate various steps in one embodiment of the method.  FIGS. 6 and 8  schematically indicate the placement step for inserting shell  10  into apparatus  90 —which is labeled as step  800 .  FIG. 6  is a front view of an individual  802  holding an example shell  10  to be opened (e.g., looking in the direction of line  5 — 5  of  FIG. 2 ).  FIG. 8  is a side view of  FIG. 6 . Shell  10  can be placed into apparatus  90  when plunger  200  is at the upper end of its linear reciprocation. Shell  10  can include shell halves  20  and  30  which halves are attached at seam  30 , and can be roughly elliptical in shape. Shell  10  can be placed with the major axis of the ellipse roughly parallel to base  110  (as shown in  FIG. 8 ). Additionally, shell  10  can be place with its minor axis slightly skewed from the vertical as shown by  FIG. 6  (such as by 15 degrees from the vertical). Placement of shell  10  slightly skewed allows tip  230  to contact one of the halves (e.g.,  20 ) instead of the seam  26 . In this way first half  20  will be sheared off of second half  30  thereby allowing easy access to the oyster inside of the shell  10 . 
       FIGS. 7 and 9  schematically indicate this shearing process which is labeled as step  810 .  FIG. 7  is a front view of shell  10  after it has been opened.  FIG. 9  is a side view of  FIG. 7 . Arrow  810  schematically indicates that tip  230  is moving downward. Arrow  820  schematically indicates that shell half  20  is being separated from shell half  30 . Arrow  356  schematically indicates that base  110  can rotate during this process. Rotation indicated by allow  356  can optimally place shell  10  in relation to tip  230  for separation of the shell halves. 
     After it completes its downward movement in the direction of arrow  810 , plunger will move up in the opposite direction of arrow  810  and another shell  10 ′ can be placed under plunger for opening. After opening the second shell then another shell  10 ″ can be placed under plunger  200  for opening. This process can be repeated until the operator finishes opening shells  10 . However, during this process no manual opening of the shell is required thereby greatly facilitating the opening process and preventing the operator from being fatigued. 
     It is believed that shearing the shell halves works better than attempting to chisel open the shell halves at seam  26 . This is because tip  230  will tend to crack portions of shell halves at seam during the chiseling process and such pieces can get into the oyster. 
       FIG. 10  is a side view of an alternative apparatus including a double mechanical separator  1000  with adjacent plungers  200 ,  200 ′. In this embodiment gear box includes two output shafts  620 ,  620 ′ which are driven by motor  650 . Conventionally available gear boxes do come with two output shafts. Output shaft  620  shaft drives plunger  200  in the same way as described above for a single plunger. However, output shaft  620 ′ drives a second plunger  200 ′. The four bar driving mechanism can be exactly the same as that described above and will not be again described. Additionally, the two plungers  200 ,  200 ′ are preferably in sync so that a single individual can simultaneously hold two shells  10 ,  10 ′ for opening by plungers  200 ,  200 ′. Alternatively, a second motor  650 ′ can be operably connected to a second gear box  600 ′ which has an output shaft which drives the second four bar mechanism and plunger  200 ′. 
       FIG. 11  is a side view of an alternative apparatus including a double mechanical separator  2000  with opposing plungers  200 ,  200 ″. In this embodiment gear box includes two output shafts  620 ,  620 ′ which are driven by motor  650 . Conventionally available gear boxes do come with two output shafts. Output shaft  620  shaft drives plunger  200  in the same way as described above for a single plunger. However, output shaft  620 ″ drives a second plunger  200 ″. The four bar driving mechanism can be exactly the same as that described above and will not be again described. Two individuals can use apparatus  90  using plungers  200 ,  200 ′—the two individuals using shells  10 ,  100 ′ for opening by plungers  200 ,  200 ′. Alternatively, a second motor  650 ′ can be operably connected to a second gear box  600 ″ which has an output shaft which drives the second four bar mechanism and plunger  200 ″. 
     Apparatus  90  has the unprecedented ability to open between 40 to 60 shells per minute and can increases in productivity depending on the operator and frequency of use. Furthermore, because of motor&#39;s  650  speed, this invention has an output capacity of 175 reciprocations per minute for opening shells. The operator is not required to use each cycle of the plunger for opening a new shell—but instead can skip one or more cycles. 
     The following is a list of parts and materials suitable for use in the present invention. 
     
       
         
               
             
               
               
             
               
               
             
           
               
                   
               
               
                 PARTS LIST 
               
             
          
           
               
                 Part Number 
                 Description 
               
               
                   
               
             
          
           
               
                 10 
                 shell 
               
               
                 20 
                 first half 
               
               
                 22 
                 outer surface 
               
               
                 26 
                 seam 
               
               
                 28 
                 meat 
               
               
                 30 
                 second half 
               
               
                 40 
                 seam 
               
               
                 50 
                 oyster 
               
               
                 90 
                 apparatus 
               
               
                 91 
                 circuit 
               
               
                 92 
                 on/off switch or emergency shutoff switch 
               
               
                 94 
                 on/off switch 
               
               
                 96 
                 breaker 
               
               
                 100 
                 press (such as Harbor Freight Tool one ton press) 
               
               
                 110 
                 base 
               
               
                 120 
                 support 
               
               
                 140 
                 opening 
               
               
                 150 
                 plate 
               
               
                 160 
                 plurality of fasteners 
               
               
                 200 
                 plunger 
               
               
                 210 
                 shaft 
               
               
                 220 
                 teeth 
               
               
                 230 
                 tip or splitter section 
               
               
                 232 
                 front 
               
               
                 234 
                 rear 
               
               
                 240 
                 first end 
               
               
                 250 
                 second end 
               
               
                 260 
                 notch 
               
               
                 270 
                 enlarged section 
               
               
                 280 
                 fasteners 
               
               
                 290 
                 base 
               
               
                 292 
                 bore 
               
               
                 294 
                 fastener 
               
               
                 300 
                 arm 
               
               
                 310 
                 first end 
               
               
                 320 
                 second end 
               
               
                 350 
                 arrow 
               
               
                 352 
                 arrow 
               
               
                 354 
                 arrow 
               
               
                 356 
                 arrow 
               
               
                 400 
                 arm 
               
               
                 410 
                 first end 
               
               
                 412 
                 adjustment for first end 
               
               
                 420 
                 second end 
               
               
                 414 
                 adjustment for second end 
               
               
                 500 
                 arm 
               
               
                 510 
                 first end 
               
               
                 520 
                 second end 
               
               
                 530 
                 gear 
               
               
                 540 
                 teeth 
               
               
                 550 
                 arm 
               
               
                 600 
                 gear reducing box (e.g., Dayton model number 4Z298) 
               
               
                 610 
                 input shaft 
               
               
                 620 
                 output shaft 
               
               
                 630 
                 gear reducing mechanism 
               
               
                 650 
                 motor (e.g., Dayton model number 6J29) 
               
               
                 700 
                 cabinet 
               
               
                 710 
                 top 
               
               
                 720 
                 sides 
               
               
                 730 
                 base 
               
               
                 750 
                 table 
               
               
                 760 
                 legs 
               
               
                 770 
                 rollers 
               
               
                 800 
                 step of positioning oyster 
               
               
                 802 
                 hand 
               
               
                 810 
                 arrow 
               
               
                 820 
                 arrow 
               
               
                 830 
                 step of separating two halves of oyster shell (e.g., by 
               
               
                   
                 shearing or by chiseling) 
               
               
                 840 
                 step of removing oyster meat from shell 
               
               
                 1000 
                 double mechanical separator with opposing plungers 
               
               
                 2000 
                 double mechanical separator with adjacent plungers 
               
               
                   
               
             
          
         
       
     
     All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise. 
     The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.