Bacon trimmer

Information

  • Patent Grant
  • 6426104
  • Patent Number
    6,426,104
  • Date Filed
    Thursday, August 3, 2000
    24 years ago
  • Date Issued
    Tuesday, July 30, 2002
    22 years ago
Abstract
A bacon trimmer for trimming cooked bacon slices into substantially uniform lengths comprises: a housing, a transfer comb mounted on the housing, a device mounted on said housing for transferring the cooked bacon slices from a continuous conveyor belt carrying the cooked bacon slices from a cooking device to a first end of said transfer comb, a device for moving the cooked bacon slices across the transfer comb to a second end of the transfer comb and feeding the cooked bacon slices to the same continuous conveyor belt adjacent the second end of said transfer comb, a cutter associated with the housing for trimming the bacon slices into substantially uniform lengths as they are transferred across the transfer comb.
Description




FIELD OF THE INVENTION




The present invention relates generally to a bacon trimmer. More particularly, it relates to a bacon trimmer for trimming cooked or pre-cooked bacon slices into substantially equal lengths. The bacon trimmer of the present invention can be readily installed in-line with existing continuous processes for cooking bacon. The present invention further relates to an improved method for preparing cooked bacon slices having a desired, substantially equal length.




BACKGROUND OF THE INVENTION




Continuous manufacturing processes for pre-cooking or cooking bacon are known. Such processes include pressing green pork bellies into a uniform shape and size in a bacon press, and feeding them into a slicer that cuts the bellies into slices. The slices are transferred along a processing direction via a conveyor belt while cure ingredients are applied to the slices. Cure ingredients may be applied, for example, to the slices by immersing them in a cure solution, or by passing the slices through a spray of a cure solution. A conveyor belt feeds the slices into a continuous cooking device where they are cooked for a sufficient time to obtain desired organoleptic properties. Examples of continuous cooking devices include microwave ovens, belt grill ovens, and impingement convection ovens. Generally, microwave oven cooking is preferred because it requires less time to cook the bacon. The cooked bacon slices are transferred via a conveyor belt to a packaging station.




One problem associated with continuous processes for cooking bacon is that the length of the bacon slices is not very uniform. Uniform length is desirable for more efficient packaging and also from the standpoint of consumer appeal. Often, to meet stringent packaging requirements, the cooked bacon slices are trimmed manually to the desired length. This is a labor intensive, slow, and imprecise process.




These and other deficiencies of prior art bacon processing are overcome with the apparatus and method disclosed herein.




SUMMARY OF THE INVENTION




It is an object of the present invention to provide a bacon trimmer for cutting or trimming cooked (or pre-cooked) bacon slices into substantially equal lengths.




It is another object of the present invention to provide a bacon trimmer that is adapted for readily installation into a continuous processes for cooking bacon, such as continuous microwave processes.




It is yet another object of the present invention to provide a bacon trimmer that trims cooked bacon slices into substantially equal lengths, while allowing excess pieces to be saved for processing into other bacon products such as bacon bits for topping.




According to an aspect of the present invention, a bacon trimmer for trimming cooked bacon slices into substantially equal lengths comprises a housing, and a transfer comb mounted on the housing. The bacon trimmer further comprises means mounted on the housing for transferring the cooked bacon slices from a first continuous conveyor belt to a first end of the transfer comb. The transferring means moves the cooked bacon slices across the transfer comb from the first end to a second end, and feeds them to the same or a second conveyor belt adjacent the second end of the transfer comb. Cutting means are mounted on the housing for trimming the bacon slices into substantially equal lengths as they are transferred across the transfer comb. Preferably, excess pieces are saved for other bacon applications, while the trimmed slices are transferred to a packaging station.




The present invention also relates to an advantageous method for making cooked bacon slices having a desired substantially uniform length. The method comprises pressing green pork bellies into substantially uniform shape and size, cutting the pork bellies into slices, cooking the slices in a cooking device, aligning the cooked slices on a conveyor belt, feeding the slices to a bacon trimmer, and trimming the slices to the desired, substantially uniform length.




The present inventive bacon trimmer and method are advantageous, because they allow production of bacon slices with a more exact, uniform length, preferably with less than about 0.25 inches, more preferably less than about 0.10 inches, and most preferably less than about 0.05 inches variance in the length of the slices. Moreover, the bacon trimmer can be readily installed in-line with continuous processes for cooking bacon.




These and other advantages of the present inventive bacon trimmer and method will become more readily apparent to those skilled in the art when the detailed description of the preferred embodiments is read in conjunction with the attached figures.











BRIEF DESCRIPTION OF THE FIGURES





FIG. 1

is a top, perspective view of a bacon trimmer according to a preferred embodiment of the invention.





FIG. 2

is a top, partial perspective view of the bacon trimmer of FIG.


1


.





FIG. 2A

is an enlarged partial perspective view of the bacon trimmer of

FIG. 1

showing the first tractor and transfer comb.





FIG. 3

is a schematic side view of the bacon trimmer of FIG.


1


.





FIG. 4

is a schematic back view of the bacon trimmer of FIG.


1


.





FIG. 5

is a simplified block diagram of a preferred embodiment of the present inventive method.





FIG. 6

is a side view of a preferred embodiment of the transfer comb employed in the bacon trimmer of the present invention.





FIG. 7

is a top view of a preferred embodiment of the transfer comb employed in the bacon trimmer of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




One aspect of the present invention relates to a bacon trimmer comprising a housing and a transfer comb mounted on the housing. The bacon trimmer further comprises means for transferring the bacon slices across the transfer comb, and cutting means for trimming the slices into trimmed slices having a desired, substantially uniform length as they are transferred across the transfer comb.




The housing is preferably mounted on wheels for ease of movement. The housing further includes an inlet and an outlet. A conveyor belt carries the cooked bacon slices from a cooking device through the housing. The housing can be of any suitable shape and is preferably sized to accommodate the conveyor belt.




The transfer comb is preferably made of a metallic or a rigid plastic material such as DELRIN, available from DuPont Chemicals, which is a crystalline polyacetal resin.




The transfer comb has a substantially flat top surface to facilitate transferring the cooked bacon slices and cutting them into trimmed slices. Preferably the transfer comb includes a plurality of longitudinally extending apertures that are sized to allow the excess bacon pieces to fall through the transfer comb and into a pan positioned below the transfer comb. Moreover, the overall shape of the transfer comb and its positioning within the housing are designed to facilitate the transfer of the bacon slices from the conveyor belt onto the first end of the transfer comb and from the second end of the transfer comb back onto the conveyor belt, where the bacon is then carried to a packaging station. For example, the transfer comb may have a substantially rectangular cross-section along a longitudinal axis extending from the first end to the second end of the transfer comb with tapered ends. The angle of the taper of each end may vary, but should preferably be less than about 40°, more preferably from about 10° to about 30°, to facilitate the transfer of the cooked slices to and from the transfer comb.




The bacon trimmer further comprises transferring means, mounted on the housing, that transfers the cooked bacon slices from the conveyor belt carrying the cooked slices from a cooking device to a first end of the transfer comb. The transferring means also moves the bacon slices across the top surface of the transfer comb from the first end to the second end of the transfer comb. The slices are trimmed into substantially equal sizes via the cutting means which are positioned according to one embodiment generally above the transfer comb. Alternatively, the cutting means can be positioned below the transfer comb. The trimmed slices are carried to the second end of the transfer comb and then are fed to the continuous conveyor belt that carries the trimmed slices to a packaging station.




In one embodiment, the conveyor belt that carries the bacon slices from the cooking device is guided through the housing. At the second end of the transfer comb, the conveyor receives the trimmed bacon slices and transfers them to the packaging station. Alternatively, two different conveyor belts may be employed, i.e., a first conveyor belt for transferring the cooked slices from the cooking oven to the first end of the transfer comb and a second conveyor belt for transferring the trimmed slices from the second end of the transfer comb down the line, for further processing or packaging.




In one embodiment, the transferring means includes a plurality of rollers rotatably mounted on the housing and a tractor. The rollers are positioned within the housing in a manner to guide the conveyor belt at close proximity to the first end of the transfer comb, beneath the transfer comb, and then up at close proximity to the other end of the transfer comb. The tractor includes a traction belt arranged in an endless loop that is supported on rotating supporting members which are mounted on the housing. The lower run of the traction belt of the tractor is substantially parallel and sufficiently close to the top surface of the transfer comb to engage the bacon slices and transfer them from the conveyor belt onto the transfer comb, move them across the top surface of the transfer comb to the other end of the transfer comb. Preferably, the traction belt is made from an elastic material such as polypropylene. Also, preferably, the traction belt has an irregular outer surface designed to create sufficient friction between the outer surface and the bacon slices to allow the traction belt to effectively transfer the bacon slices and hold them in place during the trimming action of the cutting means. A preferred traction belt is INTRALOX® belting Series 900 with while diamond top, available by Intralox, Inc., located in Harahan, La. The bacon trimmer may further comprise a gear drive mounted on the housing for transferring motion from the conveyor belt that carries the cooked bacon slices from the cooking device to the tractor. Alternatively, the tractor can be driven by a conventional motor.




Preferably, the cutting means comprise a rotary shaft and at least one pair of cutting heads securely attached to the rotary shaft. The shaft is driven by conventional means such as an electric motor. The cutting heads include at least one cutting member such as a knife or blade, and are positioned in a manner to allow the cutting members to trim the edges of the cooked bacon slices as they are transferred across the top surface of the transfer comb. Preferably, the position of the cutting heads can be adjusted dependent upon the desired length of the trimmed bacon slices. The knives or blades can be of different shapes or sizes. Preferably, the cutting means are positioned generally above the cutting members positioned substantially perpendicularly to the top surface of the transfer comb at either side of the lower run of the traction belt. Preferably, the cutting members may extend into the plane of the top surface of the transfer comb to ensure sufficient contact with the bacon slices. However, other configurations are envisioned, such as, for example, positioning the cutting means below the transfer comb.




Referring to

FIGS. 1-4

, a preferred embodiment of the present inventive bacon trimmer is provided. The bacon trimmer, includes a housing


12


of a generally rectangular shape having a front face


2


, a back face


3


, and two side faces


4


,


5


. Preferably, the housing is mounted on wheels


13


via a base structure comprising four vertical members or beams


6




a


,


6




b


,


6




c


, and


6




d


. The base structure further comprises two horizontal beams


7




a


, and


7




b


that connect vertical beams


6




a


,


6




c


, and


6




b


,


6




d


, respectively, for enhanced structural integrity. The top face of the housing


8


is preferably covered by a lid


8




a


(shown in

FIG. 4

) for preventing dust or other particulates from falling onto the bacon slices processed inside the housing.

FIGS. 1

,


2


, and


2


A show the housing without the lid


8




a


to reveal the interior parts of the bacon trimmer. Supporting structures or plates


50


,


52


are mounted on the front


2


and back face


3


of the housing, respectively, to help support and guide a conveyor belt


20


(

FIG. 3

) in and out of the housing


12


.




Plate


50


includes a pair of longitudinally extending beams


50




a


and


50




b


that are connected to vertical beams


6




d


and


6




c


, respectively. The plate


50


further includes lateral beams


50




c


and


50




d


connected to beams


50




a


and


50




b


and a plurality of rods


51


securely attached on top of the lateral beams


50




c


and


50




d


. Likewise, plate


52


includes a pair of longitudinally extending beams


52




a


and


52




b


that are connected to vertical beams


6




a


and


6




b


, respectively. The plate


52


further includes lateral beams


52




c


and


52




d


connected to beams


52




a


and


52




b


, and a plurality of rods


53


securely attached on top of the lateral beams


52




c


and


52




d


. The front face


2


and back face


3


of the housing further include protective screens


9




a


and


9




b


, respectively, that include a plurality of apertures for observing the inside of the housing when the top face is covered with lid


8




a


. Laterally extending beams


9




c


, and


9




d


connect side plates


5




a


and


4




a


to provide, among other things, additional structural integrity to the housing


12


.




The housing


12


further includes an inlet


12




a


and an outlet


12




b


(best seen in

FIG. 3

) formed between the protective screens


9




a


,


9




b


and the plates


50


,


52


, respectively. The inlet


12




a


and outlet


12




b


are sized to allow the conveyor belt


20


to pass through the housing


12


. The conveyor belt


20


carries cooked bacon slices from a continuous cooking device (not shown) such as a microwave oven.




The housing


12


further includes other means for supporting and guiding the conveyor belt


20


though the housing


12


, such as rollers


14


,


16


,


18


,


19


(best seen in FIG.


3


). Roller


19


is connected to a shaft


19




a


that is rotatably mounted to the housing. Rollers


14


,


16


and


18


are rotatably mounted on shafts


14




a


,


16




a


, and


18




a


respectively, which in turn are securely attached to the housing


12


via conventional fastening means, such as bearing plates


15


and bolts


15




a


. Alternatively, the shafts


14




a


,


16




a


and


18




a


can be welded to the housing. The rollers


14


,


16


,


18


, and


19


in conjunction with plate


50


guide the conveyor belt


20


at close proximity to the first end


38




a


of the transfer comb


38


, then under the transfer comb


38


, around rollers


18


,


16


and


14


, and finally to the other end


38




b


of the transfer comb


38


. Rollers


19


and


14


are positioned to minimize the clearance between the conveyor belt


20


and the ends


38




a


and


38




b


of the transfer comb, respectively, to facilitate the transfer of the bacon slices between the conveyor belt


20


and the transfer comb


38


.




A sprocket wheel gear


40


is attached to shaft


19




a


. Sprocket wheel gear


40


is operatively connected to gear


42


through belt


46


. Gear


42


is in turn in meshing contact with gear


44


, which is in turn mounted on a shaft


58


. Gears


40


,


42


and


44


form a gear drive


43


(shown in

FIG. 1

) for transmitting the motion of the conveyor belt


20


to a rotating shaft


58


on which rollers


26




b


,


27




b


, and


28




b


of tractors


26


,


27


, and


28


, are mounted, respectively. The gear drive


43


is positioned outside the housing for ease of maintenance.




The transfer comb


38


is mounted on the housing


12


via conventional mounting means (not shown). For example, the transfer comb can be bolted or welded to the side plates


5




a


and


4




a


of the housing. The transfer comb


38


is a metal screen made of stainless steel. It has a plurality of longitudinally extending apertures


39


(

FIG. 2A

) and a substantially flat top surface that is substantially co-planar with the plane of the top surface of the rods


51


and


53


.




In another embodiment, shown in

FIGS. 6 and 7

, the transfer comb


38


has a substantially trapezoidal side cross-section with carved sides


120


,


122


and a substantially flat top surface


124


. The transfer comb


38


of the embodiment

FIGS. 6 and 7

includes a notch


126


for securely attaching the transfer comb


38


on a cross member bar (not shown) which is in turn mounted on the housing


12


. The cross member bar is preferably made of a stainless steel. As can be seen in

FIG. 6

the transfer comb includes slots


128


for receiving the cutting means.




The bacon trimmer of

FIGS. 1-4

, includes three identical tractors


26


,


27


, and


28


. For example, tractor


26


, shown enlarged in

FIG. 2A

, includes a traction belt


26




a


arranged in an endless loop supported on two rollers


26




b


and


26




c


mounted on rotating shafts


58


and


59


, respectively. Tractors


26


,


27


, and


28


are positioned substantially parallel and sufficiently close to the top surface of the transfer comb


38


to allow the lower run of each traction belt


26




a


,


27




a


, and


28




a


, respectively, to engage the bacon slices which are carried by the conveyor belt


20


in file in rows of three, and transfer them across the top surface of the transfer comb


38


, where they are cut into substantially uniform lengths by a cutter


31


. Each tractor has a traction belt


26




a


,


27




a


,


28




a


with a width narrower than the desired length of the bacon slices so that the edges of the bacon slices extend beyond the sides of the traction belt. Rotating blades


32


positioned on each side of the traction belt cut the slices at both ends to the desired length. In operation, the tractor belts


26




a


,


27




a


, and


28




a


, pull the bacon strips off the conveyor belt


20


, transfer them across comb


38


for cutting and then places them back on the conveyor belt


20


.




The cutter


31


includes a rotating shaft


33


that is driven by a conventional motor


36


. Three pairs of disk-shaped blades


32


are attached to the rotating shaft


33


through members


34


which are in turn mounted on the shaft


33


. The blades


32


are substantially perpendicular to the top surface of the transfer comb. Preferably, the position of the disk-shaped blades


32


can be adjusted by moving members


34


on the shaft.




The shaft


33


of the cutter


31


is rotatably secured on the housing


12


via brackets


60


and


62


that are bolted to the side plates


4




a


and


5




a


, respectively. The lower run of each traction belt


26




a


,


27




a


, and


28




a


is urged against the top surface of the transfer comb


38


by a pair of weighted members


64


. This causes the bacon slices to be sufficiently extended as they are cut by the disk-shaped blades


32


. The members


64


are hanging via support elements


76


from lateral beams


70


and


72


, which are in turn removably mounted on brackets [


76


] (not shown). Members


64


are preferably threaded for adjusting the pressure exerted on the traction belts. Thus, the beams


70


,


72


can be easily removed and the length of members


64


adjusted by turning members


64


so that they are closer or further away from the beams


70


and


72


to ensure that an effective pressure is exerted against the lower run of each traction belt


26




a


,


27




a


,


28




a


to hold the bacon slices sufficiently extended against the transfer comb


38


while they are being cut. On the other hand, the exerted pressure should not significantly inhibit the motion of the traction belts. Thus, in operation, the tower run of the traction belts transfers the bacon slices across the transfer comb


38


white rotating blades


32


, positioned at either side of each traction belt


28




a


,


28




b


, and


28




c


cut the bacon slices at both ends.




The excess pieces fall through openings


80


into a pan


48


. Pan


48


can be easily removed via handle


48




a


. The traction belts


28




a


,


28




b


, and


28




c


transfer the trimmed slices to the end


38




b


of the transfer comb, and then onto the conveyor belt


20


. Conveyor belt


20


transfers the trimmed slices from the bacon trimmer to a packaging station (not shown).




The microwave conveyor belt


20


drives the tractor


26


via gear drive


43


which comprises gears


40


,


42


and


44


. Gear drive


43


is positioned outside the housing


12


for ease of maintenance. A receptacle


85


is mounted on the side plate


5




a


for knive storage for cleaning.




The present invention also relates to an improved method for preparing cooked bacon slices having a desired substantially length. One embodiment of the present inventive method comprises pressing green pork bellies into a uniform shape and size using conventional presses, according to block


100


of FIG.


5


. The method further comprises feeding the pork bellies to a conventional slicer for cutting the bellies into slices, according to block


102


. An example of a conventional slicer that can be used is slicer Model No. HS 640-3, made by Grote. Preferably, the slicer provides slices that have an average length of about 11 inches, and a thickness of about {fraction (1/16)} inches. Preferably, the slices fall directly onto a continuously moving conveyor belt that transfers the slices through a curing station, according to block


104


. Curing of the bacon slices may be accomplished by any of many well-known conventional means, before, after, or during cooking.




The method further includes cooking the slices, according to block


106


. Preferably, cooking is accomplished in a continuous mode using conventional continuous cooking devices. Preferably, a microwave oven is used, such as Model No. QMP2103 manufactured by Amana, located in Iowa. Examples of continuous manufacturing processes for cooking bacon are described in U.S. Pat. No. 5,999,925 to Wilson et al., which is incorporated herein by reference for all purposes and to the extent that is not inconsistent with the disclosure and claims of the present invention. The present inventive method further includes placing the cooked slices in file onto a conveyor belt, according to step lock


108


. The slices are arranged in single file, one behind another, or preferably, in rows of two or three slices per row. The conveyor belt transfers the cooked bacon slices to a bacon trimmer of the present invention according to step


110


. However, preferably, the positioning of the slices is done by the Grote slicer. Positioning of the cooked bacon slices in file on the conveyor belt can also be accomplished manually, for example, by an operator placing the cooked bacon slices onto marked areas on a conveyor belt. The bacon trimmer can be sized to accommodate the width of the conveyor belt of various types and sizes of cooking devices. The bacon trimmer can be equipped with one or more tractors or similar transferring means, one for each file or line of bacon slices.




The bacon trimmer cuts the slices to a desired substantially uniform length, according to step


112


. The trimmed bacon slices are transferred via the tractor to a conveyor belt that conveys the slices to a packaging station, while the excess pieces fall through the transfer comb into a pan. Preferably, the trimmed bacon slices have a uniform length with a variance or difference between the length of each trimmed slice and the desired length or average length of less than about or 0.25 inches, more preferably less than about 0.10 inches, and most preferably less than about 0.05 inches.




The present invention is not limited to the above mentioned preferred embodiments. Many variations of the present invention can be easily envisioned by those skilled in this art without departing from the scope of the invention as defined in the following claims.



Claims
  • 1. A method for preparing cooked bacon slices having a uniform desired length comprising:pressing green pork bellies into uniform shape and size; cutting the pork bellies into slices; curing the slices; cooking the slices in a cooking device; placing the cooked slices in file onto a conveyor belt; feeding the cooked slices to a bacon trimmer; and cutting the cooked slices in the bacon trimmer to a desired substantially uniform length.
  • 2. The method of claim 1, further comprising curing the slices before, after or at the same time that they are being cooked.
  • 3. The method of claim 1, wherein said bacon trimmer includes:a housing; a transfer comb mounted on the housing; means mounted on the housing for transferring the cooked bacon slices from a continuous conveyor belt carrying the cooked bacon slices from a cooking device to a first end of the transfer comb, moving the cooked bacon slices across the transfer comb to a second end of the transfer comb and feeding the cooked bacon slices to the same continuous conveyor belt adjacent the second end of the transfer comb; and cutting means mounted to the housing for trimming the bacon slices into predetermined lengths as they are transferred across the transfer comb.
  • 4. The method of claim 1, wherein said cooking device is a continuous cooking device.
  • 5. The method of claim 1, wherein said cooking device is a continuous microwave oven.
  • 6. The method of claim 1, wherein said bacon trimmer comprises a gear drive for transferring motion from the conveyor belt to a tractor and wherein a cutter is driven by a motor.
  • 7. A method for preparing cooked bacon slices having a uniform desired length comprising:pressing green pork bellies into uniform shape and size; cutting the pork bellies into slices; curing the slices; cooking the slices in a cooking device; placing the cooked slices in file onto a conveyor belt; feeding the cooked slices to a bacon trimmer; transferring the cooked slices across a comb disposed in the bacon trimmer; and cutting the cooked slices in the bacon trimmer to a desired substantially uniform length.
  • 8. The method of claim 7, further comprising curing the slices before, after or at the same time that they are being cooked.
  • 9. The method of claim 7, wherein said bacon trimmer includes:a housing; a transfer comb mounted on the housing; means mounted on the housing for transferring the cooked bacon slices from a continuous conveyor belt carrying the cooked bacon slices from a cooking device to a first end of the transfer comb, moving the cooked bacon slices across the transfer comb to a second end of the transfer comb and feeding the cooked bacon slices to the same continuous conveyor belt adjacent the second end of the transfer comb; and cutting means mounted to the housing for trimming the bacon slices into predetermined lengths as they are transferred across the transfer comb.
  • 10. The method of claim 7, wherein said cooking device is a continuous cooking device.
  • 11. The method of claim 7, wherein said cooking device is a continuous microwave oven.
  • 12. The method of claim 7, wherein said bacon trimmer comprises a gear drive for transferring motion from the conveyor belt to a tractor and wherein said cutter is driven by a motor.
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