Abstract:
A poultry skinner including a conveyor having ribs aligned to engage the upper surface of a poultry product. A rotatably mounted gripper has a plurality of radially extending fins adapted to engage the lower surface of the poultry passing between the gripper and the conveyor. An arcuate surface is mounted in closely spaced relationship to the arcuate path traveled by the rotating gripper fins and defines an opening for trapping the skin attached to the poultry product. The skin is trapped between the arcuate surface and the outer end of a rotating fin to pull the skin from the poultry product. A rotatably mounted cleaning roller having a plurality of fins is positioned in a close clearance relationship with the gripper. The rapidly rotating fins of the cleaning roller strip the poultry skin from the fins of the gripper and eject it into a collection bin below.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     (Not Applicable) 
     STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT 
     (Not Applicable) 
     REFERENCE TO AN APPENDIX 
     (Not Applicable) 
     BACKGROUND OF THE INVENTION 
     This invention relates generally to skinning devices, and more particularly to a device for removing the skin from pieces of poultry carcasses. 
     It is known in the art that there is a need for efficient and safe machines to process meats, and poultry in particular. U.S. Pat. No. 6,264,542 to Gasbarro, which is incorporated herein by reference, was a substantial advance in the technology relating to the skinning of poultry using machinery. This patent teaches a device that avoids the danger to humans of hand-skinning, and provides continuous, consistent results. Although this patent teaches a machine with many advantages, further refinement of the conventional technology is desired. Therefore, there is a need for an improved poultry skinning machine. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention contemplates an improved automated poultry product skinning apparatus. The apparatus includes a support frame provided with a product feed inlet and a product discharge outlet. A conveyor is mounted to the support frame and is aligned to engage the upper surface of a piece of poultry product delivered to the feed inlet and direct the poultry product in a path toward the discharge outlet. The conveyor is mounted to the frame for selected vertical movement of at least a forward end of the conveyor in response to the size of the poultry product delivered to the feed inlet. 
     A gripper is rotatably mounted to the frame and has a plurality of radially extending fins with outer ends disposed below the conveyor for engaging a lower side of the poultry product passing between the gripper and the conveyor. A pinch block is mounted on the frame and includes an arcuate surface positioned in a close clearance relationship to an arcuate path of the outer end of the fins during a portion of their rotation to define an opening configured to engage the outer skin attached to the poultry product between the outer ends of the fins and the arcuate surface of the pinch block. The close clearance relationship and the opening are configured to firmly entrap the attached outer skin between the outer end of each of the fins and the arcuate surface of the pinch block to pull the outer skin from its attachment to the underlying meat portions of the poultry product. 
     An improvement lies in a cleaning roller that is rotatably mounted to the frame of the skinning apparatus adjacent the gripper. The cleaning roller has a plurality of radially extending fins with ends that are disposed in a close clearance relationship to the ends of the fins of the gripper. During operation of the skinning apparatus, the rapidly rotating fins of the cleaning roller strip poultry skin from the gripper and eject the skin downwardly into a collection bin. By performing this primary cleaning function, the cleaning roller allows the gripper to operate cleanly and efficiently with a significantly reduced need for additional spray water cleaning as compared to previous embodiments of the skinning apparatus. 
     An alternative embodiment of the improved skinning apparatus is contemplated in which the cleaning roller is rotatably mounted to an adjustment bracket that is pivotably mounted at one end to the frame of the skinning apparatus. An adjustment cam is rotatably mounted to the frame below the opposite end of the adjustment bracket and engages the adjustment bracket. By rotating the adjustment cam, the adjustment bracket and the cleaning roller can be moved incrementally nearer to the gripper. Thus, as the fins of the gripper accumulate wear and shorten over time, the close clearance relationship between the fins of the cleaning roller and the fins of the gripper can be maintained by periodic, incremental rotation of the adjustment cam. 
     Another alternative embodiment of the improved skinning apparatus is contemplated in which the gripper has a series of longitudinally-spaced, annular grooves formed in it and the cleaning roller has a series of radially and longitudinally-spaced teeth projecting from each of its fins. During operation of the skinning apparatus, the teeth of the cleaning roller extend into and rotate through the grooves in the gripper. The teeth of the cleaning roller thereby dig and pull substantially all skin and waste matter from the fins of the gripper. This allows the skinning apparatus to be operated without requiring any additional cleaning means such as pressurized water spray. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a cutaway side view illustrating the preferred embodiment of the present invention. 
         FIG. 2  is a cutaway enlarged side view illustrating the embodiment of  FIG. 1 . 
         FIG. 3  is a cutaway enlarged side view illustrating the embodiment of  FIG. 1  with a piece of poultry product being skinned by the skinning apparatus. 
         FIG. 4  is a cutaway enlarged side view illustrating a first alternative embodiment of the present invention. 
         FIG. 5  is a perspective view illustrating the gripper and the cleaning roller of a second alternative embodiment of the present invention. 
     
    
    
     In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific term so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. 
     DETAILED DESCRIPTION OF THE INVENTION 
     An apparatus constructed for skinning pieces of poultry product is illustrated and described in U.S. Pat. No. 6,264,542 to Gasbarro, and is incorporated herein by reference.  FIG. 1  shows a skinning apparatus  10  having a supporting frame  20 , which can be mounted on a base or table  22 , for conveniently locating the apparatus and the auxiliary product and skin collection means where desired. 
     Referring to  FIGS. 1 and 2 , the support frame  20  has a first sidewall (not shown in  FIG. 2 ) and a second sidewall  26 . The sidewalls are mounted to the base  22  in any conventional manner well-known to those of ordinary skill in the art, such as by welding or bolt fasteners. The bottom of the frame  20  is open to communicate with a chute for receiving the skin portion removed from the poultry product sections and directing them to a collection area, such as a bin. 
     A rear discharge opening in the frame  20  includes a ramp-like structure  32  that directs the product after it has been skinned to a collection area, which is separate from the removed skin, via a chute. The separate collection area for the skinned product may be a conventional bin or a conveyor (not shown), and may be located in the area  35 . 
     The frame  20  includes a frontal opening between the sidewalls which forms a product feed inlet  28 . A conventional endless belt conveyor  31  may be employed to load product and carry it to the feed inlet  28  where it is delivered to a skinning station, indicated in  FIG. 1  generally at  38 . However, other forms of conveying the product to the feed inlet  28  may be employed to deliver the product to the skinning station  38  without departing from the present invention. 
     The belt  40  is mounted on a support block  64  and is driven by a motor to rotate in a clockwise direction in the orientation shown in  FIG. 1 . The support block  64  is mounted to the sidewall  26  in a vertically movable relationship, thereby permitting the gap between the lower run of the belt  40  and the gripper  42  (described below) to automatically adjust to the size of poultry sections received therebetween. This can be accomplished, for example, by a pivot at the leftward end of the support block  64  about which the support block  64  pivots, or a plurality of vertical bearing rods extending through the support block  64 , permitting vertical movement. The driven shaft  58  preferably forms a pivot axis for the support block  64 . The combined weight of the support block  64  and its attached structures biases the block downwardly toward the gripper  42  at its rightward end as shown in  FIG. 1 . Thus, poultry sections placed on the conveyor  31  and conveyed to between the belt  40  and the gripper  42  cause the support block  64  to adjust upwardly to the size of the sections to be skinned, and yet the support block  64  maintains a substantially constant downward force on the poultry section during the skin removal operation. 
     The belt  40  transports pieces of poultry section entering the feed inlet  28  to the gripper  42 , and over the gripper  42 . The gripper  42  is rotatably mounted to the frame  20  and is driven by a conventional motor to rotate in a counterclockwise direction (in the  FIG. 1  illustration) so that the top of the gripper  42  moves in the same direction as the lower run of the belt  40 . The belt  40  and the gripper  42  cooperatively move the poultry sections toward the discharge opening, and function in cooperation with the pinch block  44  to engage and pull the outer skin off the poultry sections as described in detail below. 
     The belt  40 , conveyor  31 , gripper  42 , cleaning roller  85  (described below) and other moving parts of the apparatus are driven by one or more conventional electric motors (not shown) and a conventional series of sprockets and drive chains. The belt  40  is mounted in the apparatus in a manner similar to the chain belt (also called “sticker chain”) described in U.S. Pat. No. 6,264,542, referenced above. The belt  40  is formed from a plurality of pivotably-linked metal pieces extending in an endless loop around the driven and idler shafts  58  and  59 . The belt  40  can be formed entirely from flexible material, such as food grade urethane, or can be formed from a flexible membrane to which rigid ribs are fastened, such as by adhesive. The ribs of the belt enable the belt  40  to drive the poultry sections coming into contact with the belt  40  in the desired direction. The relative spacing of each of the ribs can be varied to provide sufficient grip for many poultry types. 
     The support block  64  upon which the belt  40  is mounted functions essentially the same as described in U.S. Pat. No. 6,264,542. Thus, when a poultry section enters the feed inlet  28  and is carried over the gripper  42 , product larger than the defined space will cause the forward end of support block  64  to move upward about the pivot point of the drive shaft  58  and carry with it the forward end of the belt  40  that is operatively mounted thereon as described above. A stop is preferably employed to limit the downward movement of the forward end of the support block  64 . 
     The gripper  42  comprises a generally cylindrical member provided with a plurality of raised projections or fins  86 . Preferably, the fins  86  are formed by creating axially aligned V-shaped recesses or voids in the outer cylindrical surface of a cylindrical body to leave an essentially flat surface  88  at the outer end of each fin  86 . A central bore is provided in the gripper  42  to fixedly receive the drive shaft  56 , which is rotatably mounted through the sidewall  26 . 
     The pinch block  44  includes an arcuate surface  45  disposed in an adjacent, close tolerance relationship to the arcuate path defined by the rotation of the outer surfaces  88  of the fins  86  of the gripper  42 . The upper end of the arcuate surface  45  closely mates with the end of each fin  88  as it approaches the pinch block  44 . Referring to  FIG. 3 , a piece of poultry  90  engaged by the belt  40  and the outer ends  88  of the fins  86  is carried toward the opening between the upper end of the arcuate surface  45  and the outer ends  88  of the fins  86 . The outer end  88  of each fin  86  engages the poultry product  90 , and, approaching this opening, cooperates with a lip  47  defining the upper end of the arcuate surface  45 , to pinch or trap the skin  92  of the poultry product  90  between the outer end  88  and the arcuate surface  45 . 
     As the piece of poultry  90  is carried toward the discharge opening by the combined action of the belt  40  and the gripper  42 , which rotate at similar speeds, the outer end  88  of each fin  86  continues to pull the point of engagement with the skin  92  downwardly against the arcuate surface  45 . In the more preferred embodiment shown, each successive fin  86  engages a spaced point of contact with the skin  92  of the piece of poultry  90  in a similar manner relative to a forwardly moving adjacent fin. With this continuous pulling by successive fins  86 , the skin  92  is continuously pulled from the poultry section  90  in one piece without cutting, tearing or ripping of the skin  92 . If the skin  92  is torn or ripped significantly by the engagement of the fins  86  with the belt  40  or the initial engagement with the pinch block  44 , strips or large areas of skin are likely to remain adhered to the underlying muscle and require undesirable subsequent manual removal. Thus, such tearing is to be avoided if possible. 
     The outer ends  88  of the gripper  42 , which ends engage and trap the skin  92  against the arcuate surface  45 , continue to pull portions of skin  92  downwardly along the arcuate surface  45  as the poultry piece  90  is engaged by the gripper  42  and the belt  40 . The poultry product  90  continues to move toward the discharge opening and the chute  32 , and, when the poultry product  90  is completely skinned by the apparatus, the poultry product  90  falls down the chute  32  under the force of gravity. 
     The skin  92  of the poultry product, however, continues to be pulled downwardly, toward the lower apex of the gripper  42 . In some cases, the skin falls from the gripper  42  under the force of gravity once the skin is no longer sufficiently held between the pinch block  44  and the gripper  42 . In other cases, the skin will remain stuck to the fins  86  of the gripper  42 , in which case the skin must be removed from the gripper  42  by other means before the skin is carried back toward the top of the gripper  42  where it could interfere with the skinning of other poultry products. It is in this context that the cleaning roller  85  provides substantial advantages over the skinning apparatus described in U.S. Pat. No. 6,264,542, referenced above. 
     Referring to  FIGS. 2 and 3 , the cleaning roller  85  is substantially identical in construction to the gripper  42 , but has a smaller diameter. Like the gripper  42 , the cleaning roller  85  is generally cylindrical with a plurality of radially-projecting fins  87 . The cleaning roller  85  is rotatably mounted to the sidewall  26  of the skinning apparatus on a drive shaft  57  at a position below and slightly forward of the gripper  42 , with the tips of the fins  87  in a close clearance relationship with the tips of the fins  86  of the gripper. The axis of rotation of the cleaning roller  85  is substantially parallel to the axis of rotation of the gripper  42 . The cleaning roller can be rotated by the same motor that drives the belt  40  or the gripper  42 , or it can be rotated by a separate motor. The cleaning roller  85  rotates in the same (counterclockwise in  FIGS. 2 and 3 ) direction as the gripper  42  but at a significantly greater speed (at the tips), and therefore it will become apparent that if the cleaning roller  85  is driven by the same motor as the gripper  42 , the gearing will have to be modified compared to the gripper  42  to accomplish this greater speed of rotation. Thus, as the skin  92  of the poultry product  90  exits the pinch block  44  and is pulled down and forward by the fins  86  on the lower left quadrant of the gripper  42 , the skin  92  is transferred to the fins  87  on the upper left quadrant of the cleaning roller  85 , which rotate in a down and rearward direction. The skin  92  is thereby scraped and pulled off of the fins  86  of the gripper  42  by the fins  87  of the cleaning roller  85 . The skin  92  is then ejected in a downward direction from the rapidly rotating fins  87  cleaning roller  85 , which rotates faster and produces greater centrifugal force than the larger diameter gripper  42 . 
     A water manifold (not shown) sprays water onto the fins  86  of the gripper  42  to assist in the removal of skin and waste matter therefrom. However, due to the primary cleaning function performed by the cleaning roller  85 , a much lower water pressure, and therefore a greatly reduced quantity of water, is required relative to previous embodiments of the skinning apparatus that lacked the cleaning roller  85  and that instead relied on water spray as a primary cleaning means. Specifically, the water spray of the present invention is preferably disbursed at about 40 psi at a rate of about 0.75 gallons per minute (GPM). The cleaning roller  85  therefore allows the skinning apparatus to be operated cleanly and efficiently with a substantial savings of water. 
     Referring to  FIG. 4 , an alternative embodiment of the skinning apparatus is shown wherein the cleaning roller  85  and its drive shaft  57  are rotatably mounted to a movable adjustment bracket  100 . The adjustment bracket  100  is pivotably mounted at a first horizontal end to the sidewall  26  of the skinning apparatus by a pivot pin  102 . A support pin  104  extends from the sidewall  26  through a vertically-elongated adjustment slot  106  in the adjustment bracket  100  at a second, opposite horizontal end, which is preferably the forward end. The cleaning roller  85  and its drive shaft  57  can thereby pivot about the axis of the pivot pin  102 , with such movement being limited by engagement between the support pin  104  and the edge of the adjustment slot  106 . 
     An adjustment cam  108  is rotatably mounted to the skinning apparatus  10  by a pivot pin mounted in the sidewall  26  below the forward end of the adjustment bracket  100  with the adjustment cam  108  engaging a bottom edge of the adjustment bracket  100 . Rotating the adjustment cam  108  causes the forward end of the adjustment bracket  100  to be pivoted upwardly or downwardly about the pivot pin  102  depending on whether the portion of the adjustment cam  108  that engages the adjustment bracket  100  is an increased or a decreased distance from the pivot pin, thereby moving the cleaning roller  85  nearer or farther away from the gripper  42 . The adjustment cam  108  is preferably coupled to a conventional ratcheting mechanism (not within view) that allows the adjustment cam  108  to be incrementally rotated in a clockwise direction while preventing the adjustment cam  108  from being rotated in a counterclockwise direction. 
     The fins  86  of the gripper  42  experience wear and slowly shorten during regular operation of the skinning apparatus. The overall diameter of the gripper  42  therefore decreases over time. Similar wear is possible on the cleaning roller  85 . As this shortening occurs, the gap between the fins  86  of the gripper  42  and the fins  87  of the cleaning roller  85  increases, thereby degrading the ability of the cleaning roller  85  to engage and remove skin from the gripper  42 . In order to account for the accumulation of wear on the gripper  42  and maintain the close clearance relationship between the fins  86  of the gripper  42  and the fins  87  of the cleaning roller  85 , an operator can simply rotate the adjustment cam  108  on a periodic basis to incrementally move the cleaning roller  85  closer to the gripper  42 . The performance of the cleaning roller  85  can thereby be preserved until it eventually becomes necessary to replace the gripper  42 . 
     Referring now to  FIG. 5 , an alternative gripper  242  and cleaning roller  285  are contemplated for facilitating the removal of poultry skin and other waste matter from the gripper  242  without the use of any water. The gripper  242  and cleaning roller  285  are installed in the skinning station  38  in a substantially identical manner to the gripper  42  and cleaning roller  85  described above and differ in structure therefrom in the following respects. The gripper  242  has a series of longitudinally-spaced, annular grooves  204  formed in it. The cleaning roller  285  has a series of complementary, radially protruding and longitudinally-spaced teeth  206  that project from each of its fins  208 . The longitudinal space between each tooth  206  and each immediately adjacent tooth  206  on the cleaning roller  285  is substantially equal to the longitudinal space between each pair of longitudinally-adjacent annular grooves  204  in the gripper  242 . Thus, the teeth  206  and the grooves  204  matingly engage. 
     During operation, the teeth  206  of the cleaning roller  285  extend into and rotate through the annular grooves  204  in the gripper  242 . The teeth  206  thereby dig and pull substantially all skin and waste matter from the fins  210  of the gripper  242 . The skin and waste matter are then rapidly ejected from the cleaning roller  285  by centrifugal force in the manner described above. The grooved gripper  242  and toothed cleaning roller  285  thereby allow the skinning apparatus  10  to be operated without requiring any additional cleaning means such as water spray. The gripper  242  and cleaning roller  285  are shown as having six annular grooves  204  and six longitudinally-spaced rings of teeth  206 , respectively, although it is contemplated that a fewer or greater number of annular grooves  204  and corresponding rings of teeth  206  can be used without departing from the present invention. 
     Referring back to  FIG. 3 , by controlling the downward pressure that is applied by the belt  40  to the piece of poultry  90  against the gripper  42  and the opening to the arcuate surface  45  of the pinch block  44 , gripping of the outer skin  92  is accomplished with very little or no damage to the underlying meat portions. This results in a very high percentage of the processed poultry pieces having the whole skin removed in substantially one piece, increasing production rates and decreasing loss of muscle product compared to the prior art. 
     Although the gripper  42  is shown in  FIG. 2  with 20 fins  86 , the number of fins can be varied by replacing the gripper  42  with another gripper of similar outer diameter and length. Varying the number of the fins, which varies the size of the fins and the voids between the fins, varies the amount of fat removed with the skin from the poultry section. The more fins there are, the less fat that is removed from the poultry product, and therefore the larger the fat layer that remains on the poultry product. Thus, if one desires a very thin layer of fat remaining on the poultry, one can replace the gripper  42 , which has 20 fins, with a gripper having 22 or 24 fins, or flights. Of course, one can alternatively make grippers with 18, 16, 14, 12, 10, 8, 6 or even 4 fins, although this is generally not desirable. The desired range of fins is between about 8 and about 30 fins. 
     In view of the foregoing description herein, it should be readily understood that the present invention provides an improved apparatus and method for removing the skin from poultry product pieces that improves yield and is of relatively simple construction and efficient in operation. 
     This detailed description in connection with the drawings is intended principally as a description of the presently preferred embodiments of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. The description sets forth the designs, functions, means, and methods of implementing the invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and features may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention and that various modifications may be adopted without departing from the invention or scope of the following claims.