Method and apparatus for cutting a case containing product

Information

  • Patent Grant
  • 6694852
  • Patent Number
    6,694,852
  • Date Filed
    Friday, November 10, 2000
    24 years ago
  • Date Issued
    Tuesday, February 24, 2004
    20 years ago
Abstract
An apparatus and method for cutting open a case of product having a top and a bottom is provided. The case is placed on a conveyor and moved to a cutting apparatus. The top is cut open at the cutting apparatus. The case is moved to a lift apparatus. The top of the case is opened and the product is lifted from the bottom of the case. The case is then cut thereby separating the bottom of the case from the top of the case.
Description




CROSS-REFERENCE TO RELATED APPLICATIONS




Not Applicable




STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT




Not Applicable




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to packaging and, more particularly, to an apparatus and method for cutting open a case of goods.




2. Description of Relating Art




Prepackaged goods to be sold in retail outlets are commonly shipped in large cardboard containers or cases. Each case holds a specific number of the prepackaged goods.




Typically the cases are packed and shipped from the manufacturers' plant to a distribution center. At the distribution center, the cases are opened and the prepackaged goods are prepared for shipping to the retail store. Often, the goods are re-packaged at the distribution center into display cartons for display at the store.




For example, breakfast cereal is typically sold in rectangular boxes to the consumer. The cereal boxes are packaged in large cases at the manufacturer's plant and delivered to distribution centers, where they are prepared for shipping to retail stores, e.g., grocery stores. At the distribution center, the cases are manually opened and the cereal boxes are removed and repackaged into trays for display at the store.




This process is generally inefficient and costly and creates unnecessary waste material. The present invention is aimed at one or more of the problems set forth above.




SUMMARY OF THE INVENTION




In one aspect of the present invention, an apparatus for cutting open a case of product is provided. The case includes a top and a bottom. The apparatus includes a conveyor having a first end and a second end. The conveyor is adapted to move the case from the first end to the second end. The apparatus also includes a top cutting apparatus, a lift apparatus, and a bottom cutting apparatus. The top cutting apparatus includes at least one cutting device and is adapted to cut open the top of the case. The lift apparatus includes first and second arrays of suction cups. The first array of suction cups is adapted to open the top of the case and the second array of suction cups is adapted to lift the product from the bottom of the case. The bottom cutting apparatus includes at least one cutting device and is adapted to cut the case thereby separating the bottom of the case from the top of the case.




In another aspect of the present invention, a method for cutting open a case of product having a top and a bottom is provided. The method includes the steps of placing the case on a first end of a conveyor belt, moving the case to a top cutting apparatus using the conveyor belt, and cutting open the top of the case. The method further includes the steps of moving the case to a lift apparatus using the conveyor, opening the top of the case, lifting the product from the bottom of the case, and cutting the case thereby separating the bottom of the case from the top of the case.











BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING





FIG. 1

is an illustration of an apparatus for cutting a case containing product, according to an embodiment of the present invention;





FIG. 2

is an illustration of an exemplary case illustrating a plurality of cuts on the case made by the apparatus of

FIG. 1

;





FIG. 3

is an illustration of a top cutting apparatus of the apparatus of

FIG. 1

, according to an embodiment of the present invention;





FIG. 4

is an illustration of a portion of a lift apparatus of the apparatus of

FIG. 1

, according to an embodiment of the present invention;





FIG. 5

is an illustration of another portion of the lift apparatus of

FIG. 4

, according to an embodiment of the present invention;





FIG. 6

is an illustration of still another portion of the lift apparatus of

FIG. 4

, according to an embodiment of the present invention;





FIG. 7

is an illustration of an exemplary case illustrating the cuts on the case made by the apparatus of

FIG. 1

, according to a second embodiment; and





FIG. 8

is a partial view of the apparatus of

FIG. 1

, according to an embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




With reference to the drawings and in operation, the present invention provides an apparatus and method for cutting open a case of product.




With specific reference to

FIG. 1

in one embodiment of the present invention, the case cutting apparatus


100


includes a conveyor


102


, a loading station


104


, a top cutting apparatus


106


, a lift apparatus


108


, a bottom cutting apparatus


110


and a removing apparatus


112


. The conveyor


102


, top cutting apparatus


106


, lift apparatus


108


, and bottom cutting apparatus


110


are mounted to a frame


113


.




With specific reference to

FIG. 2

, a case


202


has a top


204


and a bottom


206


. The top


204


is composed of first and second minor or dust flaps


208


A,


208


B (shown in dotted lines) and first and second major flaps


210


A,


210


B. The first and second minor flaps


208


A,


208


B are folded down below the first and second major flaps


210


A,


210


B. The case


202


is sealed by glue, tape or other appropriate means.




Returning to

FIG. 1

, the conveyor


102


has a first end


114


and a second end


116


. The conveyor


102


is adapted to move the case


202


from the first end


114


to the second end


116


. In the preferred embodiment, the conveyor


102


is a drag conveyor. The drag conveyor


102


has two chains


118


A,


118


B, one on each side of the conveyor


102


. A conveyer surface


120


is composed of a plurality of cross-bars


121


. The case


202


, as it moves down the conveyor


102


, is guided by an adjustable side guide


122


running substantially the length of the conveyor


102


and a plurality of aluminum bars


125


, known as flight bars. The aluminum bars


125


are used to position the cases


202


at predetermined intervals along the conveyor


102


and to drag the cases


202


along the conveyer surface


120


. A drag conveyor is well known in the art and is therefore not further discussed.




The top cutting apparatus


106


includes at least one cutting device and is adapted to cut open the top


204


of the case


202


. In the preferred embodiment, the top cutting apparatus


106


includes a first top cutting apparatus


124


and a second top cutting apparatus


126


.




With reference to

FIG. 3

, the first top cutting apparatus


124


includes first and second cutting devices


302


,


304


and is adapted to cut the top of the case


202


along first and second opposite sides of the top


204


of the case


202


. Preferably, the first and second cutting devices


302


,


304


are stationery rotary knives positioned transverse to the top


204


of the case


202


, i.e., at an angle relative to the top


204


so as to cut through the major flaps


210


A,


210


B. Each device


302


,


304


includes an electric motor


306


,


308


and a rotary blade


310


,


312


. The cuts in the top


204


of the case


202


are made as the case is drawn past the rotary knives


302


,


304


by the conveyor


102


.




The second top cutting apparatus


126


includes a third cutting device


314


and is adapted to cut the top


204


of the case between the first and second opposite sides. In the preferred embodiment, the third cutting device


314


is a movable rotary knife positioned transverse to the top


204


of the case


202


. The third cutting device


314


includes an electric motor


316


and a rotary blade


318


. The third cutting device


314


is mounted on first and second guide bars


320


A,


320


B. A chain drive system


322


includes a chain


324


and a chain drive motor


326


. The chain drive system


322


moves the third cutting device


314


from side to side. In operation, the case


202


is stopped at a predetermined location (see below) and the third cutting device


314


is moved from one side to the other thereby cutting the top


204


. The third cutting device


314


is retained at the other side until the next case arrives, at which time the third cutting device


314


motion is reversed, i.e., moved back to the one side.




Referring again to

FIG. 2

in the preferred embodiment, the first top cutting apparatus and the second top cutting apparatus


124


,


126


are designed to cut the top


204


of the case


202


in a generally “H” shaped pattern defined by first, second and third line segments


212


,


214


,


216


. The “H” shaped pattern of cuts allows the top


204


of the case


202


to be opened (see below).




The cuts indicated by the first and second line segments


212


,


214


are made by the first and second cutting devices


302


,


304


. The cut indicated by the third line segment


216


is made by the third cutting device


314


. As shown, the third line segment


216


is generally in the middle section of the top


204


, however, it overlaps the minor flap


208


A on one side. The third cutting device


314


is adjusted to cut through the major flaps


210


A,


210


B, but not through or only partially through the underlying minor flap


208


A. This is to ensure that the product in the case


202


is not damaged.




In one embodiment as shown in

FIG. 3

, the first and second cutting devices


302


,


304


are mounted on manually adjustable first and second mounts


328


,


330


, respectively. The third cutting device


314


is mounted on first and second side mounts


332


,


334


. In a second embodiment, the first, second, and third cutting devices


302


,


304


,


314


are adjustable by four coupled hydraulic lifts (not shown).




With reference to

FIGS. 4-6

, the lift apparatus


108


includes first and second arrays of suction cups


402


,


602


. The first array of suction cups


402


is adapted to open the top


204


of the case


202


and the second array of suction cups


602


is adapted to lift the product from the bottom


206


of the case


202


.




With specific reference to

FIG. 4

, the lift apparatus


108


includes a first assembly


400


. The first assembly


400


includes an assembly frame


404


mounted to a supporting structure


128


attached to the frame


113


. The first assembly


400


includes a linkage assembly


406


coupled to a first actuator


408


. In one embodiment, the first actuator


408


is a pneumatic cylinder, but other suitable types of actuators may also be used, e.g., an electronic solenoid.




The linkage assembly


406


includes a first linkage


410


rotatably coupled to the first actuator


408


. The first linkage


410


is rotatably coupled to a first end of a v-shaped linkage


412


. The v-shaped linkage


412


is coupled to a first opening assembly


414


through the assembly frame


404


.




The first opening assembly


414


includes a first arm


416


and a second arm


418


. The first arm


416


is adjustable to compensate for different case sizes. The second arm


418


is mounted to the first arm


416


. The first array of suction cups


402


is coupled to the second arm


418


.




In operation, as the first actuator


408


extends, the first opening assembly


414


rotates in the direction of the arrow A. The first actuator


408


is stopped such that the first array of suction cups


402


is in contact with the top


204


of the case


202


. Preferably, there are two suction cups


420


A,


420


B mounted on the second arm


418


.




A pneumatic system (not shown) creates a vacuum through the suction cups


402


A,


402


B, thereby temporarily coupling the suction cups


402


A,


402


B with one half of the top


204


. Such pneumatic systems are known in the art and are therefore, not further discussed.




Thereafter, the first actuator


408


is contracted rotating the first opening assembly


414


in the reverse direction.




With reference to

FIGS. 4 and 5

, the linkage assembly


406


includes a connecting linkage


422


rotatably coupled, at one end, to a second end of the v-shaped linkage


412


and to a second linkage


424


at the other end. The second linkage


424


is coupled through the assembly frame


404


to a second opening assembly


502


.




The second opening assembly


502


includes a third arm


504


and a fourth arm


506


. The third arm


504


is connected to the second linkage


424


. The fourth arm


506


is connected to the third arm


504


. Preferably the first array of suction cups


402


includes third and fourth suction cups


508


A,


508


B. The second opening assembly


502


works in conjunction with the first opening assembly


414


by virtue of the connecting linkage


422


. The third and fourth suction cups


508


A,


508


B are also part of the pneumatic system. The second opening assembly


502


operates in a manner similar to the first opening assembly


414


.




With reference to

FIG. 6

in one embodiment, the lift apparatus


108


includes a carriage assembly


600


. The carriage assembly


600


includes an upper carriage assembly


604


and a lower carriage assembly


606


. The upper carriage assembly


604


is movably mounted to the supporting structure


128


.




The upper carriage assembly


604


includes a platform


608


underneath which are mounted four supporting blocks


610


A,


610


B,


610


C, (only which three are visible. The supporting blocks


610


A,


610


B,


610


C, have apertures through which first and second horizontal guide bars


130


A,


130


B run (see FIG.


1


). The first and second horizontal guide bars


130


A,


130


B are mounted to the supporting structure


128


.




A carriage drive system


132


controllably moves the carriage assembly


600


along the supporting structure


128


. The drive system


132


includes an electric motor


134


and a pair of drive chains


136


A,


136


B. The drive chains


136


A,


136


B are coupled to a pair of brackets


612


A,


612


B (see

FIG. 6

) mounted on the upper carriage assembly


604


.




The carriage assembly


600


includes a first and second vertical guide bars


614


A,


614


B. The first and second vertical guide bars


614


A,


614


B are slidably coupled to the upper carriage assembly


604


. The lower carriage assembly


606


includes an upper support structure


616


and a lower support structure


618


. The upper support structure


616


includes two apertures through which the first and second vertical guide


614


A,


614


B bars run through. The first and second vertical guide bars


614


A,


614


B also run through two apertures in the platform


608


of the upper carriage assembly


604


. The first and second vertical guide bars


614


A,


614


B are coupled to the lower support structure


618


.




Third and fourth vertical guide bars


620


A,


620


B are mounted to inner surfaces of the upper carriage assembly


604


via brackets


622


A,


622


B,


622


C,


622


D. The upper support structure


616


is slidably coupled to the third and fourth vertical guide bars


620


A,


620


B by brackets


624


A,


624


B.




A second actuator


626


is coupled between the upper carriage assembly


604


and the lower support structure


618


. The second actuator


626


is adapted to controllably move the lower support structure


618


relative to the upper carriage assembly


604


.




A third actuator


628


is coupled between the platform


608


and the lower support structure


618


. The third actuator is adapted to controllably move the lower support structure


618


relative to the platform


608


.




The second array of suction cups


602


includes a plurality of suction cups (only two of which are shown


630


A,


630


B). The number of suction cups is equal to the number of boxes of product contained in the case


202


(there is only one level of product per case).




The bottom cutting apparatus


110


includes at least one cutting device


138


and is adapted to cut the case


202


thereby separating the bottom


206


of the case


202


from the top


204


of the case


202


.




In the preferred embodiment, the bottom cutting apparatus


110


includes first and second bottom cutting devices


138


A,


138


B. In the preferred embodiment, the first and second bottom cutting devices


138


A,


138


B are electric-driven rotary knives having a rotary blade


139


A,


139


B and an electric motor (not shown).




Preferably, the first and second bottom cutting devices


138


A,


138


B are positioned on opposite sides of the case


202


.




Preferably, the rotary blades


139


A,


139


B are in the same vertical plane relative to the case


202


, but are slightly horizontally offset, i.e., the center of one of the rotary blades


139


A,


139


B is in front of the other relative to the conveyor


102


. Additionally, both rotary blades


139


A,


139


B are slightly over the centerline of the conveyor


102


. This arrangement ensures that the case


202


is completely cut through and that the rotary blades


139


A,


139


A do not interfere with each other.




The first and second bottom cutting devices


138


A,


138


B are preferably stationery relative to the frame


113


. As discussed below, the product within the box is lifted from the bottom


206


of the case


202


. The product and the case


202


are then moved along the conveyor


102


past the first and second bottom cutting devices


138


A,


138


B which cut through the case


202


, below the product. The product is then released and allowed to settle back into the case


202


.




As shown in

FIG. 2

in one embodiment, the bottom cutting apparatus


110


is adapted to cut the case


202


around the sides near the bottom


206


, as indicated by line


218


. As shown in

FIG. 7

, the case


202


may include a pre-cut perforated section


702


. The perforated section


702


is used to create a display window within a display tray or bottom


206


of the case


202


. The bottom cutting apparatus


110


is adjustable such that the bottom


206


is cut from the case above the cutout section


702


, as indicated by line


218


′.




The apparatus


100


further includes a control system


140


. Preferably, the control system


140


includes a programmable logic controller or PLC (not shown). The control system


140


includes relays for turning on and off the electric motors


306


,


308


,


316


which control the rotary blades


310


,


312


,


318


and the pneumatic system. The control system


140


further includes a START button


142


and a STOP button


144


. The control system


140


may also include switches or buttons (not shown) for starting the electric motors


306


,


308


,


316


in sequence. Alternatively, the PLC may be programmed to start the electric motors


306


,


308


,


316


in a predefined sequence. The control system


140


is operably coupled to the top cutting apparatus


106


, lift apparatus


108


, and bottom cutting apparatus


110


in a conventional manner to control actuation thereof.




With reference to

FIG. 8

, the operation of the apparatus


100


will now be explained. The apparatus


100


will normally be run by two operators (not shown). The apparatus


100


is started by actuation of the START button


142


. In response to actuation of the START button


142


, the control system


140


starts the electric motors


134


,


306


,


308


,


316


,


322


,


326


. The first operator loads cases


202


unto the conveyor


102


at the first loading station


104


.




As discussed below, the apparatus


100


has a number of stations along the conveyer


102


at which the conveyer


102


is stopped. These stations are preferably a preset distance apart, e.g., 60 inches, The aluminum bars


125


are spaced accordingly to ensure that the cases are spaced correctly.




After a case


202


has been loaded onto the conveyor


102


, the control system


140


advances the conveyor


102


until the loaded case has reached a second station


802


. A sensor (not shown) is mounted below the conveyor


102


and is used to sense when a case


202


has reached the second station


802


. Preferably, the sensor detects the aluminum bar


125


behind the loaded case


202


. The sensor may be a proximity sensor, photo-detector or other suitable sensor.




The first top cutting device


124


is positioned ahead of the second station


802


such that the top


204


of the case


202


is cut along the sides as discussed above by the first top cutting apparatus


124


as the case


202


moves toward the second station


802


.




While the loaded case


202


is stationery at the second station


802


, the control system


140


controllably actuates the second top cutting apparatus


126


to cut the top


204


from one side to the other (as discussed above), completing the H-shaped cut pattern.




During this time, the first operator has loaded another case onto the conveyor


102


at the loading station


104


.




The control system


140


then moves the conveyor


102


until the first loaded case


202


reaches a third station


804


. At the third station


804


, the control system


140


controllably actuates the first and second opening assemblies


414


,


502


as discussed above to open the case


202


, i.e., lift the two cut portions of the top


204


. The control system


104


controllably actuates the carriage assembly


600


to controllably lift the product from the bottom of the case. First, the second actuator


626


is extended to lower the lower carriage assembly


606


into position. Then the third actuator


628


is extended to lower the lower support structure


618


so that the second array of suction cups


602


are in contact with the product. The pneumatic system is then actuated so that the product can be lifted. The third actuator


628


is then contracted to lift the product from the bottom of the case


202


.




Once this is completed, the conveyor


102


is advanced so that the case


202


is moved to the removal station


112


. Simultaneously, the control system


140


actuates the carriage drive system


132


to move the carriage assembly


600


and the product along with the case.




In transit to the removing station


112


, the bottom cutting apparatus


110


cuts through the sides of the case


202


separating the top


204


and the bottom


206


.




Once the case


202


arrives at the removing station


122


, the second operator removes the case


202


from conveyor


102


. The top


206


of the case


202


may also be removed.




Each time the conveyor


102


is stopped, the second and third stations


802


,


804


contain a case


202


. The first operator loads a case


202


onto the conveyor


102


at the loading station


104


and the second operator removes a case


202


from the conveyor


102


at the unloading station


112


.





















100




apparatus







102




conveyor







104




loading apparatus







106




top cutting apparatus







108




lift apparatus







110




bottom cutting apparatus







112




removing apparatus







113




frame







114




first end of conveyor







116




second end of conveyor







118




chain (A, B)







120




conveyer surface







122




adjustable guide







124




first top cutting apparatus







125




aluminum bar







126




second top cutting apparatus







128




supporting structure







130A




first horizontal guide bar







130B




second horizontal guide bar







132




carriage drive system







134




electric motor







136




drive chains (A, B)







138A




first bottom cutting device







138B




second bottom cutting device







140




control system







142




START button







144




STOP button







202




case







204




top







206




bottom







208A




first minor flap







208B




second minor flap







210A




first major flap







210B




second major flap







302




first cutting device







304




second cutting device







306




electric motor







308




electric motor







310




rotary blade







312




rotary blade







314




third cutting device







316




electric motor







318




rotary blade







320A




first guide bar







320B




second guide bar







322




chain drive system







324




chain







326




chain drive motor







328




first mount







330




second mount







332




first side mount







334




second side mount







400




first assembly







402




first array of suction cubs







404




assembly frame







406




linkage assembly







408




first actuator







410




first linkage







412




v-shaped linkage







414




first opening assembly







416




first arm







418




second arm







420




suction cup (A, B)







422




connecting linkage







424




second linkage







502




second opening assembly







504




third arm







506




fourth arm







508




suction cups (A, B)







600




carriage assembly







602




second array of suction cups







604




upper carriage assembly







606




lower carriage assembly







608




platform







610




supporting blocks (A, B, C, D)







612




brackets (A, B)







614A




first vertical guide bar







614B




second vertical guide bar







616




upper support structure







618




lower support structure







620A




third vertical guide bar







620B




fourth vertical guide bar







622




brackets (A, B, C, D)







624




brackets (A, B)







626




second actuator







628




third actuator







630




suction cups (A, B)














Claims
  • 1. An apparatus for cutting open a case of product, the case having a top and a bottom, comprising:a conveyor having a first end and a second end and being adapted to move the case from the first end to the second end; a top cutting apparatus having at least one cutting device and being adapted to cut open the top of the case; a lift apparatus having first and second arrays of suction cups, the first array of suction cups being adapted to open the top of the case and the second array of suction cups being adapted to lift the product from the bottom of the case; and a bottom cutting apparatus having at least one cutting device and being adapted to cut the case thereby separating the bottom of the case from the top of the case after the product has been removed from the bottom of the case, the lift apparatus thereafter returning the product to the bottom of the case.
  • 2. An apparatus, as set forth in claim 1, the top cutting apparatus includes a plurality of cutting devices for cutting the top of the case in a generally “H” shaped pattern.
  • 3. An apparatus, as set forth in claim 1, including a control system for automatically controlling the conveyor, top cutting apparatus, lift apparatus and bottom cutting apparatus.
  • 4. An apparatus, as set forth in claim 3, wherein said control system includes a control box with a start button and a stop button.
  • 5. An apparatus, as set forth in claim 1, wherein the top cutting apparatus includes a pair of stationery rotary knives positioned transverse to the top of the case, the top cutting apparatus being adapted to cut the top of the case along first and second opposite sides of the top of the case.
  • 6. An apparatus, as set forth in claim 5, wherein the top cutting apparatus includes a movable rotary knife positioned transverse to the top of the case, the top cutting apparatus being adapted to cut the top of the case from the first opposite side to the second opposite side.
  • 7. An apparatus, as set forth in claim 1, wherein the bottom cutting apparatus includes first and second bottom cutting rotary knives.
  • 8. An apparatus, as set forth in claim 7, wherein the first and second bottom cutting rotary knives are positioned on opposite sides of the case transverse to sides of the case.
  • 9. An apparatus, as set forth in claim 8, wherein the first bottom cutting rotary knife is horizontally offset from the second bottom cutting rotary knife.
  • 10. An apparatus for cutting open a case of product, the case having a top and a bottom, comprising:a conveyor having a first and a second end and being adapted to move the case from the first end to the second end; a first top cutting apparatus having first and second cutting devices and being adapted to cut the top of the case along first and second opposite sides of the top of the case; a second top cutting apparatus having a third cutting device and being adapted to cut the top of the case between the opposite sides; a lift apparatus having first and second arrays of suction cups, the first array of suction cups being adapted to open the top of the case and the second array of suction cups being adapted to lift the product from the bottom of the case; and a bottom cutting apparatus having at least one cutting device and being adapted to cut the case thereby separating the bottom of the case from the top of the case after the product has been removed from the bottom of the case, the lift apparatus thereafter returning the product to the bottom of the case.
  • 11. An apparatus, as set forth in claim 10, the top cutting apparatus includes a plurality of cutting devices for cutting the top of the case in a generally “H” shaped pattern.
  • 12. An apparatus, as set forth in claim 10, including a control system for automatically controlling the conveyor, top cutting apparatus, lift apparatus and bottom cutting apparatus.
  • 13. An apparatus, as set forth in claim 12, wherein said control system includes a control box with a start button and a stop button.
  • 14. An apparatus, as set forth in claim 10, wherein the first top cutting apparatus includes a pair of stationery rotary knives positioned transverse to the top of the case, the top cutting apparatus being adapted to cut the top off of the case along first and second opposite sides of the top of the case.
  • 15. An apparatus, as set forth in claim 14, wherein the second top cutting apparatus includes a movable rotary knife positioned transverse to the top of the case, the top cutting apparatus being adapted to cut the top of the case from the first opposite side to the second opposite side.
  • 16. An apparatus, as set forth in claim 10, wherein the bottom cutting apparatus includes first and second bottom cutting rotary knives.
  • 17. An apparatus, as set forth in claim 16, wherein the first and second bottom cutting rotary knives are positioned on opposite sides of the case transverse to sides of the case.
  • 18. An apparatus, as set forth in claim 17, wherein the first and second bottom cutting rotary knives are horizontally offset.
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