Abstract:
A stacking conveyor for receiving slices cut from a food loaf or slab includes a frame, an endless belt conveying surface, a carrier, a plurality of pins, and a motive mechanism. The endless belt conveying surface is supported by the frame. The carrier is arranged beneath the top surface of the endless belt conveying surface. The plurality of pins protrude upward from the carrier, each of the pins having a sharp top end. The motive mechanism is configured for raising the carrier to elevate the top ends of the pins above the top surface of the endless belt conveying surface to receive and impale a first slice of a stack. The pins are then retracted beneath the conveying surface.

Description:
[0001]     This application claims the benefit of U.S. Provisional Application Ser. No. 60/689,452 filed Jun. 10, 2005. 
     
    
     TECHNICAL FIELD OF THE INVENTION  
       [0002]     The invention relates to conveyors for slicing machines, particularly to conveyors which accumulate slices in a stack.  
       BACKGROUND OF THE INVENTION  
       [0003]     U.S. Pat. Nos. 5,649,463 and 5,704,265 describe high speed slicing machines having stacking conveyors that receive slices that are cut from a loaf. In a slicing machine operation, the slices fall onto the stacking conveyor and are formed into a stack, either a straight stack or a shingled stack. This stacking conveyor is sometimes referred to as a jump conveyor. The jump conveyor moves completed stacks from beneath the slicing blade onto a further conveyor to be conveyed eventually to a sorting and/or packaging operation. The jump conveyor can be provided with a vertical lift mechanism which allows the jump conveyor to descend as the stack is forming to ensure a constant drop distance from the loaf onto the preceding slice. The jump conveyor can be provided with a lateral movement means wherein stack corrections can be made or shingled stack patterns can be accumulated or product shuffled stacks can be created such as disclosed in U.S. Pat. No. 6,763,750.  
         [0004]     The present inventors have recognized that sometimes the first slice that begins an accumulated stack does not land and remain in a desirable orientation or position on the conveyor surface. The first slice can slide or bounce somewhat or can be slightly folded on an edge, on the conveyor surface. The slices that follow the first slice however have the advantage of the propensity of the slices to adhere together and the aforementioned problems are reduced.  
         [0005]     The present inventors have recognized that it would be desirable to provide a mechanism for ensuring that the first slice cut from a loaf and received on a stacking conveyor surface landed and was maintained in a flat, properly positioned orientation for receiving the second and subsequent slices thereon.  
       SUMMARY OF THE INVENTION  
       [0006]     The invention provides a stacking conveyor for receiving slices cut from a food loaf or slab that includes a frame, an endless belt conveying surface, a carrier, a plurality of pins, and a motive mechanism. The endless belt conveying surface is supported by the frame. The carrier is arranged beneath the top surface of the endless belt conveying surface. The plurality of pins protrude upward from the carrier, each of the pins having a sharp top end. The motive mechanism is configured for raising the carrier to elevate the top ends of the pins above the top surface of the endless belt conveying surface.  
         [0007]     Preferably the motive mechanism also acts to lower the carrier, although gravity or a spring could be used as well to create the lowering movement.  
         [0008]     The motive mechanism can comprise an actuator, preferably a pneumatic cylinder, mounted to the frame and having a cylinder rod engaged to the carrier.  
         [0009]     A tray can be located below the endless belt conveying surface and above the carrier; the tray providing openings for the pins to protrude through the tray.  
         [0010]     Preferably, the conveying surface is formed by a plurality of endless belts and at least some of the plurality of pins are arranged to protrude between adjacent belts.  
         [0011]     Preferably, the carrier comprises a plate having threaded holes, and the pins each include a shank with a threaded portion that engages into one of the threaded holes.  
         [0012]     The preferred embodiment of the invention is effective at receiving a slice dropped from a loaf or slab to be impaled on the pins and prevented from bouncing or sliding on a conveying surface. Once the landing of the slice is fixed by the pins, the pins can be withdrawn and further slices can be stacked effectively and neatly on the properly oriented first slice.  
         [0013]     Numerous other advantages and features of the present invention will be become readily apparent from the following detailed description of the invention and the embodiments thereof, and from the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a schematical sectional view of a high-speed slicing machine;  
         [0015]      FIG. 2  is not enlarged portion of the slice machine shown in  FIG. 1 , and taken generally along line  2 - 2  of  FIG. 3 ;  
         [0016]      FIG. 3  is a plan view of the enlarged portion of  FIG. 2 ; and  
         [0017]      FIG. 4  is an elevational view of one pin used in the invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]     While this invention is susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the specific embodiments illustrated.  
         [0019]      FIG. 1  shows in cross-section a slicing machine  20  that incorporates the present invention. Such a slicing machine is disclosed for example in U.S. Pat. Nos. 5,628,237; 5,649,463; 5,704,265; and 6,484,615 herein incorporated by reference, as well as the commercially available FX-180™ and FX plus™ slicing machines available from Formax, Inc. of Mokena Ill., USA.  
         [0020]     The slicing machine  20  includes a rotating slicing blade  24  that is driven by a slicing blade drive  28 . A loaf feed the apparatus  32  controllably feeds a loaf  34  into a cutting plane defined by the rotating slicing blade  24 . As slices are removed from the loaf  34 , the slices drop onto a stacking conveyor  40 , also known as a jump conveyor. Such jump conveyors are known and can be configured as described in U.S. Pat. Nos. 5,628,237; 5,649,463; 5,704,265; or 6,763,750, herein incorporated by reference.  
         [0021]     The jump conveyor  40  includes an endless belt conveying surface  44  that is displaceable vertically between the elevated position  44   a  and a lowered position  44   b . In operation, as slices  45  are removed from the loaf  34  and accumulate in a stack  46 , either a straight stack or a shingled stack, on the conveying surface  44 , the conveying surface  44  is progressively moved downwardly to accommodate the increasing height of the stack so that each slice falls from the loaf across a similar distance.  
         [0022]      FIG. 2  illustrates an enlarged portion of  FIG. 1 , particularly, the configuration of the conveyor  40 . The conveyor  40  includes a front roller  52  that is driven in rotation by a controlled motive means, and a rear roller  54 . A plurality of spaced-apart belts  56  form the conveying surface  44 . The belts  56  are wrapped around the rollers  52 ,  54 . Beneath the belts  56  is a tray  60  that serves as a vertical support for the belts.  
         [0023]     A pin deployment apparatus  66  is mounted beneath the tray  60 . The pin deployment apparatus includes a carrier in the form of a pin plate  68  arranged in substantial parallelism with the tray  60 , beneath the tray  60 . The pin plate  68  carries a plurality of pins  72  which extend upwardly from the pin plate  68  through apertures  74  arranged through the tray  60 . The pin plate  68  is fastened to at least one actuator, preferably linear actuators in the form of a pair of spaced-apart pneumatic cylinders  80 ,  81 . The pneumatic cylinders  80 ,  81  are identical and only the pneumatic cylinder  80  will be described. The pneumatic cylinders raise and lower the pin plate  68 , together.  
         [0024]     The pneumatic cylinder  80  includes a cylinder body  82  having pneumatic ports  84   a ,  84   b  and a piston driven cylinder rod  86 . The cylinder body  82  is fastened to a transverse brace bar  92  that is fastened at opposite ends thereof to side plates  94 ,  95  (shown in  FIG. 3 ) of the conveyor  40 . Long fasteners  96  having heads  98  extend through the cylinder body  82  through spacers  102  and are engaged into threaded holes  103  in the brace bar  92 . The cylinder rod  86  passes through a bushing  106  that is fit within an opening  108  through the brace bar  92 . In this way, the cylinder rod  86  can smoothly, and with reduced friction, reciprocate through the brace bar  92 . Preferably, the bushing is composed of HYDEX 4101L material.  
         [0025]     The pin plate  68  is fastened to an end of the actuator rod  86  using a single fastener  110  that has a top surface flush with the top surface of the pin plate  68 . Each pin  72  is a unitary part that includes a sharp end portion  112  that merges into a hexagonal tool-engageable shoulder  116  that merges into a shank  118 . The shank  118  includes a threaded portion  120  that is threaded into a threaded hole  122  in the pin plate  68 . Using a wrench or similar tool from above, and gripping the shoulder  116  the pin is turned to advance the threaded portion  120  into the threaded hole  122 .  
         [0026]     The pneumatic cylinders  80 ,  81  are preferably of a type commercially available as from Bimba Manufacturing Company of Monee, Ill., USA, particularly a BIMBA FLAT 1, model FOS. The stroke used as preferably one quarter inch. The length of the cylinder rod is somewhat increased over standard rods.  
         [0027]     As shown in  FIG. 2 , a slice  45  has been deposited onto the pins  72  with the end portions  112  penetrating into the slice to some degree. Preferably, the number of pins is sufficient such that the slice is held slightly elevated from the top surface of the belts  56 . The pins  72  act to hold the slice at its initial position of deployment onto the conveyor belt  44  when dropped from the loaf during the slicing operation. At some point after they slice has been engaged by the pins  72 , the cylinders  80 ,  81  are actuated to retract the actuating rods  86  downward to displace the pin plate  68  downward and to withdraw the pins from engagement with the slice. The slice  45  and the subsequent stack  46  are then fully supported by the conveyor belt  44  to be transported thereby by circulation of the belts.  
         [0028]     Preferably the pins are retracted sometime after the first slice has been positioned. The pins are retracted such that the sharp portions  112  are located below the top surface of the belts  56  so as not to interfere with the movement of the formed stack  46  along the belts  56  as the roller  52  is driven into rotation to displace the formed stack off of the conveyor  40 .  
         [0029]     The brace bar  92 , the tray  60 , the pin plate  68 , and the side plates  94 ,  95  are all preferably composed of  304  stainless steel.  
         [0030]      FIG. 3  shows in plan view the conveyor  40 . The brace bar  92  is fastened by two fasteners  136  to each end plate  94 ,  95 . The rollers  52 ,  54  are journaled for rotation and supported by the side plates  94 ,  95 . The pin plate  68  is shown dashed as it is beneath the tray  60 .  FIG. 3  illustrates the landing footprints  45   a  of slices  45  to be received by the conveyor  40 . According to this illustrated arrangement, the sliced product to be stacked is 4¼ inch bologna slices.  
         [0031]      FIG. 3  illustrates that a plurality of tray apertures  74  can be arranged in a grid pattern through the tray  60 . As viewed within the apertures  74 , some, but not all, of the apertures  74  have received pins  72 . Furthermore, the pin plate  68  can include a greater number of threaded holes  122  than there are corresponding apertures  74 . In other words, not every threaded hole  122  must include a corresponding aperture  74 , and not every aperture  74  need receive a pin  72 . The reason for this flexibility in numbers allows the machine to be adapted for different products of different sizes, different weights and/or different requirements. Thus, the machine can be fine-tuned by installing or removing pins  72  from the threaded holes  122 . Additionally, the pin plate  68  can be provided with a universal number and rectangular grid pattern of threaded holes and the tray  60  need not have an identical number of apertures  74 . This assists in manufacturing and standardization of parts and machine methods.  
         [0032]      FIG. 4  illustrates one pin  72 . Preferably, the pin is machined down from a hexagonal stock piece to form the shoulder portion  116 . The sharp end portion  112  preferably has a sharpness angle A of about 20 degrees and a length dimension B of about 0.17 inches. The remaining dimensions are approximately to the scale shown. Preferably, the pin  72  is composed of  316  stainless steel material.  
         [0033]     From the foregoing, it will be observed that numerous variations and modifications may be effected without departing from the spirit and scope of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred.