Barrel cam loader arm assembly

Information

  • Patent Grant
  • 6308502
  • Patent Number
    6,308,502
  • Date Filed
    Wednesday, December 29, 1999
    24 years ago
  • Date Issued
    Tuesday, October 30, 2001
    22 years ago
Abstract
A loader arm assembly for use in a packaging system, comprising an arm, a housing, and a load jam detector. The housing is operably connected to at least one motive mechanism, and is adapted for moving the arm to load product into a package. The arm has both a latched state and a released state with respect to the housing. The arm normally is in the latched state to load product into the package, and enters the released state to relieve pressure upon detecting the load jam condition. The arm includes a base plate and a loading head. The housing is formed with a guide passage that is adapted for receiving the base plate. The load jam detector preferably includes at least one detent adapted for holding the base plate with respect to the housing in the latched state. The detent preferably is formed by a tip of at least one plug extending through the housing to the guide passage. The tip is adapted for applying a holding force against the base plate. A first end of the base plate has at least one depression adapted for receiving the tip of the at least one plug in the latched state and for releasing the tip to slide on a surface of the base plate upon the application of a predetermined load pressure attributable to the load condition. The loader arm assembly is described and shown within a barrel cam loading mechanism that is incorporated into a continuous motion packaging mechanism, but may be used in other packaging systems such as a vertical cartoner or a sleever.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates, generally, to apparatus and methods in the packaging industry. More particularly, the invention relates to a barrel cam loader arm assembly incorporated into a barrel cam loading mechanism used within a packaging system.




2. Background Information




The state of the art in general includes various packaging devices and methods. These devices and methods are believed to have significant limitations and shortcomings. Specifically, the article groups may jam within an article group transfer mechanism and may damage the articles or the carton. One solution for detecting and relieving pressure associated with a load jam is described in U.S. Pat. No. 5,347,796, owned by the applicants' assignee, which discloses a release mechanism that is connected to a cam assembly in the article group transfer mechanism. The release mechanism, such as a pressure release cylinder and piston, is controlled by a sensing mechanism such as a photoeye or capacitive proximity sensor. An excessive force placed on the outer rail of the cam assembly due to a jamming of the arm assembly, for example, will actuate the release mechanism enabling the outer rail to pivot away. However, the amount of force required to actuate the release mechanism will vary depending on where the loader arm is with respect to the pivot point on the outer rail assembly, i.e. more force is required near the pivot point and less force is required away from the pivot point. Additionally, once the release mechanism is actuated due to a jam, multiple lanes of articles and packages may be damaged, which requires an operator to clean and reset each of these lanes.




This invention provides each barrel cam loader arm assembly within the barrel cam loading mechanism with an independent means for detecting a load jam that is believed to constitute an improvement over existing technology. The sensitivity of the independent means for detecting a load jam is adjustable to account for the degree that the articles and packages are sturdy or delicate, and it remains constant or consistent as each arm assembly travels within the loader arm assembly.




BRIEF SUMMARY OF THE INVENTION




The present invention provides a loader arm assembly incorporated into a barrel cam loading mechanism used within a packaging system such as a cartoner or a sleever. The loader arm assembly generally comprises an arm, a housing, and means for detecting a load jam condition. The housing is operably connected to at least one motive mechanism and is adapted for moving the arm to load product into a package. The arm has both a latched state and a released sate with respect to the housing. The arm normally is in the latched state to load product into the package, and enters the released state to relieve pressure upon detecting the load jam condition. The arm includes a base plate and a loading head.




The base plate has a first end and a second end. The housing is formed with a guide passage that is adapted for receiving the base plate. The means for detecting a load jam preferably includes at least one detent adapted for holding the base plate with respect to the housing in the latched state. The detent(s) preferably is formed by a tip of at least one plug extending through the housing to the guide passage. The tip is adapted for applying a holding force against the base plate. The first end of the base plate has at least one depression adapted for receiving the tip of the plug(s) in the latched state and for releasing the tip to slide on a surface of the base plate upon the application of a predetermined load pressure attributable to the load jam condition.




The motive mechanism(s) includes a flight chain and guide tube assembly adapted for providing a longitudinal motion to the housing and a control cam assembly operably positioned with respect to the flight chain and guide tube assembly to provide a lateral motion to the housing. The flight chain and guide tube assembly includes a parallel pair of flight chains and at least one guide tube connected to and extending between the flight chains. The housing has at least one guide tube aperture adapted for slidably receiving the guide tube(s), and includes a cam follower adapted for operably contacting the control cam assembly. The control cam assembly engages and influences the housing to laterally move along the guide tube(s) as the flight chain and guide tube assembly longitudinally transport the housing and the arm in a longitudinal direction.




The housing includes a body portion and a cover portion removably attached to the body portion. Both the body portion and the cover portion have cooperating channels to form the guide passage adapted for receiving the base plate and for laterally moving the arm to load product into a package if the arm is and remains in the latched state. The plug(s) extends through the cover portion to the guide passage. The plug(s) and depression(s) provide the arm with both the latched state in which the arm moves laterally with the housing and the released state in which the arm does not move laterally with the housing. The plug(s) have threads and extend through a threaded aperture in the cover portion. The holding force corresponding to the predetermined load pressure that is attributable to the load jam condition may be adjusted by turning the plug(s) or by using more or fewer plug(s). Therefore, each arm assembly in the barrel cam loading mechanism has an independent means for detecting a load jam that has a sensitivity that is adjustable to account for the degree that the articles and packages are sturdy or delicate, and is constant or consistent as each arm assembly travels within the loader arm assembly.




The loader arm assembly is described and shown within a barrel cam loading mechanism that is incorporated into a continuous motion packaging mechanism. The barrel cam loading mechanism generally comprises a plurality of the loader arm assemblies described above, a flight chain and guide tube assembly, and a control cam assembly. The flight chain and guide tube assembly is adapted for providing a longitudinal motion to the housing of each of the loader arm assemblies, and generally includes a parallel pair of longitudinally oriented flight chains and at least one guide tube for each of the plurality of loader arm assemblies connected to and laterally extending between the flight chains. The guide tube(s) has a slidable fit within guide tube aperture(s) in the housing. The plurality of loader arm assemblies are disposed along the flight chains at predetermined longitudinally spaced intervals. The control cam assembly is operably positioned proximate to the flight chain and guide tube assembly to provide a lateral motion to the housing of each of the loader arm assemblies. The control cam assembly influences the housing to laterally move along the guide tube(s) as the flight chain and guide tube assembly longitudinally transports the housing.




The packaging system may be a continuous motion packaging mechanism, or cartoner, which generally comprises a carton supply and transport mechanism, an article supply mechanism, an article group selection and transport mechanism, and the barrel cam loading mechanism described above. The carton supply and transport mechanism is adapted for providing a linear stream of longitudinally spaced carton sleeves. The article supply mechanism is adapted for providing streams of articles to a predetermined position. The article group selection and transport mechanism is disposed adjacent and parallel to the carton supply and transport mechanism, and is adapted for metering the articles provided by the article supply mechanism into predetermined article groups and for transporting a linear stream of longitudinally spaced article groups that are aligned with the carton sleeves, thus enabling the barrel cam loading mechanism to load the article groups into the carton sleeves. An example of a high-speed cartoner is described in U.S. Pat. No. 5,347,796, owned by the applicants' assignee, and is herein incorporated by reference. Alternatively, the packaging system may be a vertical cartoner or a sleever. An example of a vertical cartoner is described in U.S. Pat. No. 4,802,324 and an example of a sleever is described in U.S. Pat. No. 5,036,644, both of which are owned by the applicants' assignee and are herein incorporated by reference.




The features, benefits and objects of this invention will become clear to those skilled in the art by reference to the following description, claims and drawings.











BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING





FIG. 1

is a side view of a cartoner incorporating the loader arm assemblies of the present invention within a barrel cam loading mechanism.





FIG. 2

is a top view of the cartoner taken along line


2





2


of FIG.


1


.





FIG. 3

is a top view of the barrel cam loading mechanism incorporated into the cartoner.





FIG. 4

is a side view of the barrel cam loading mechanism incorporating the loader arm assembly of the present invention.





FIG. 5

is a top view of the barrel cam loading mechanism taken along line


5





5


of FIG.


4


.





FIG. 6

is an end view of the barrel cam loading mechanism taken along line


6





6


of FIG.


4


.





FIG. 7

is a side view of the loader arm assembly.





FIG. 8

is a perspective view of a partially-extended loader arm assembly.





FIG. 9

is an exploded view of the base plate and housing of the loader arm assembly of FIG.


7


.





FIG. 10

is plan view illustrating the inside of the cover portion and body portion of the housing, and the top surface of the base plate.





FIG. 11

is a perspective view illustrating the bottom of the body portion of the housing.





FIG. 12

is a top view of the loader arm assembly when the arm is in a retracted, latched state.





FIG. 13

is a top view of the loader arm assembly when the arm is in a partially extended, latched state.





FIG. 14

is a top view of the loader arm assembly when the arm is in a partially extended, released state.











DETAILED DESCRIPTION




Referring to

FIGS. 1-14

, an example of the preferred embodiment of the present invention is illustrated and generally indicated by the reference numeral


10


. The barrel cam loader arm assembly


10


of the present invention is described and shown within a barrel cam loading mechanism


14


that is incorporated into a packaging system such as a continuous motion cartoner


12


. The invention is described below first by describing a cartoner


12


, which is illustrated in

FIGS. 1-3

, and then by describing the barrel cam loading mechanism


14


, which is illustrated in

FIGS. 4-6

, and finally by describing the barrel cam loader arm assembly


10


, which is illustrated in

FIGS. 7-14

.




Continuous Motion Cartoner




The cartoner


12


is a continuous, high-speed packaging mechanism adapted for packaging articles


20


or products of varying types, sizes and quantities into paper board carriers or cartons


22


of varying types and sizes in a reliable, continuous and high-speed process. For example, the cartoner


12


may package standard beverage cans or bottles into common single configurations or into stacked configurations. Moreover, the process of loading beverage containers into cartons


22


, for example, is accomplished quickly and reliably, under typical industry tolerances for both container and carrier construction. The resultant filled cartons


22


output by the cartoner


12


are of uniform consistency having maximized squareness and tautness for improved storage qualities and transportability.




Referring to

FIGS. 1-3

, the cartoner


12


generally comprises a carton supply and transport mechanism


30


or stream, an article group selection and transport mechanism


32


or stream, a pair (for stacked article groups) of article supply mechanisms


34


or streams, a divider placement mechanism


36


used for stacked article groups, and an article group transfer apparatus, i.e. the cross-loading or barrel cam loading mechanism


14


. These mechanisms are shown to be supported by a unitary frame structure


38


, although if aligned properly, separate support structures may be utilized consistent with the teachings of this invention.




The carton supply placer


56


of the carton supply and transport mechanism


30


is disposed proximate to an input end


40


of the cartoner


12


, and carton sleeves or blanks


24


are subsequently transported in a linear fashion on a carton transport conveyor


58


to an output end


42


. The article supply mechanism or mechanisms


34


are also disposed at the input end


40


. Two article supply mechanisms


34


are used in a cartoner


12


adapted for packaging articles in a stacked configuration comprised of two layers. A first portion


44


of each article supply mechanism


34


is disposed spatially parallel to the article group selection and transport mechanism


32


, and a second portion


46


merges, at a predetermined angle, with the article group selection and transport mechanism


32


to supply streams of product or articles to two separate positions along the article group selection and transport mechanism


32


. These merging mechanisms are further constructed and arranged to meter individual articles, via a fixed flight bar arrangement, into predetermined article groups on the mechanism.




In the cartoner embodiment adapted for packaging stacked article groups shown in the figures, the stacking function of the device is accomplished by forming a first group


48


at a low level, placing a divider sheet on the lower group via the divider sheet placement mechanism


36


, and then simultaneously forming a second group


50


downstream at a higher level and allowing the upper group


50


to slide across the divider sheet by the action of the flight bars of the article group selecting portion of the mechanism


32


to form the stacked group


542


. The divider placement mechanism


36


preferably comprises a rotary placer mechanism.




The article group selection and transport mechanism


32


is disposed adjacent and parallel to the carton supply and transport mechanism


30


and extends downstream, in a linear orientation. Merged or combined article groups


52


are transported downstream on an article group transport conveyor


54


in a spaced and metered fashion, each group being aligned with a carton sleeve


24


traveling on the carton transport conveyor


58


.




The barrel cam loading mechanism


14


is disposed adjacent to and parallel with the article group transport conveyor


54


, and extends and travels longitudinally with respect to the cartoner


12


. The barrel cam loading mechanism


14


has a plurality of loading arm assemblies


10


, including arms that extend transversely or perpendicularly with respect to the article group and carton transport conveyors


54


and


58


. The loading arms


10


move product on the article group transport conveyor


54


into aligned carton sleeves


24


traveling on the carton transport conveyor


58


, thereby loading the carton sleeves


24


with the articles


20


.




The carton supply and transport mechanism


30


preferably includes a rotary type carton supply placer


56


. The carton supply placer


56


is supported above the input end


40


of the carton supply and transport mechanism


30


by a vertically adjustable frame structure, and basically transfers flat carton blanks or sleeves


24


from a power magazine to the surface of the carton transport conveyor


58


and simultaneously opens the blank so that it assumes a four-sided configuration with opposing open ends bounded by at least one flap each. The partially erected carton, i.e. carton sleeve


24


, is placed in a transverse or lateral orientation so that its ends are open to the sides of the carton transport conveyor


58


for loading purposes. The carton transport conveyor


58


receives cartons from the carton supply placer


56


and transports them linearly downstream with respect to the overall cartoner


12


. The downstream transport of carton sleeves


24


is synchronized with the article group selection and transport mechanism


32


and with the barrel cam loading mechanism


14


, as described further below, to effectuate carton loading. The carton transport conveyor


58


is adjustable to accommodate cartons of varying types and sizes, and basically comprises a plurality of flight lugs which are connected to a pair of flight chains that are connected to and revolve about drive and idler ends. The number of lugs per carton may be varied for alternative carton configurations, and the transverse and longitudinal spacing between lugs on the parallel, side-by-side chains is preferably variable to allow a variety of carton configurations to be received on the carton transport conveyor. Adjustment is desirable to permit the apparatus to be used with various carton configurations to allow for adjustment of carton spacing. The carton supply and transport mechanism


30


may also include a carton stabilization structure to support the tops of the relatively tall, bi-level carton sleeves


24


traveling on the mechanism, particularly during the loading phase of operation.




The first or lower article supply mechanism


34




a


provides a plurality of input individual articles at a first predetermined level or height and at a predetermined point on the article group selection and transport mechanism


32


. The lower article supply mechanism


34




a


is shown to comprise a conveyor disposed about a drive sprocket/shaft assembly and an idler sprocket/shaft assembly. The conveyor preferably consists of a unitary belt. Articles transported on the top, forward run of the conveyor are separated into a plurality of single file paths by lane separators


60


. Each lane separator has a terminal portion of a predetermined length, such that it extends into the path of the article group selection and transport mechanism


32


. Each terminal portion is constructed such that it allows longitudinally transported flight structures of the article group selection and transport mechanism


32


to pass through the angled conveyance lanes. As the flight bars mesh with and pass through the lane separator end portions, they engage articles disposed in lanes and rake them onto the longitudinal conveyance path of the mechanism and between adjacent flight bars. The combination of forces exerted by the flight bars, lane ends, and conveyor serve to select and meter individual articles into predetermined article groups


48


which are fully merged onto the article group selection and transport mechanism


32


. The size, orientation and dimensions of the resultant product groups are dependent upon the number of infeed lanes, product dimensions, and the configuration and spacing of the flight bars. Lanes may be blocked off by closure means to alter the group size and/or orientation. The lane separators and the flight bars are adjustable to provide full variability of product group parameters.




The article group selection and transport mechanism


32


selects article groups


48


from the first or lower article supply mechanism


34




a


as set forth above and from the second or high article supply mechanism


34




b


discussed below, and transports them linearly downstream with respect to the overall cartoner


12


. The downstream transport of article groups


48


is synchronized with the carton supply and transport mechanism


30


and with the barrel cam loading mechanism


14


, as described further below, to effectuate carton loading. The article group selection and transport mechanism


32


comprises a conveyor


54


, a plurality of flight bar assemblies fixed to and longitudinally transported on the conveyor, and a plurality of slide plates, which are disposed on the conveyor between the spaced flight bars. The conveyor


54


includes a drive sprocket/shaft assembly, an idler sprocket/shaft assembly, and a pair of parallel endless conveyor chains that are connected to and revolve about the sprocket/shaft assemblies to form a longitudinally extending forward or top run and a return or bottom run. The flight bar assemblies include a top rail member and a bottom rail member that are connected to one another by vertical spacers. The top and bottom members are disposed parallel to one another and are spatially separated by the spacers. Each top and bottom member further has an angled front end and an elongated, rectilinear body terminating in a flat back end. The front end slants or angles inwardly from its leading edge to its trailing edge to enable the flight bars to select individual articles disposed in the article infeed lanes and to separate them from the closely spaced nearest upstream article. A pair of fixed slide plates are connected to each flight bar assembly. Both the flight bars and the slide plates are connected to the flight chains via connection brackets. The slide plates are thin, flat structures with a low friction top surface which support the lower article groups and further permit sliding movement thereon. Additionally, slotted slide plates are disposed between adjacent flight bar assemblies.




The second or higher article supply mechanism


34




b


provides a plurality of input individual articles to the apparatus at a second predetermined level or height and at a predetermined point downstream from the lower article supply mechanism


34




a.


The higher mechanism


34




a


also comprises a conveyor disposed about a drive sprocket/shaft assembly and an idler sprocket/shaft assembly. Articles transported on the top, forward run of the conveyors are separated into a plurality of single file paths by lane separators


60


. Each lane separator


60


has a terminal portion of a predetermined length, such that it extends into the path of the article group selection and transport mechanism


32


a predetermined distance. Each terminal portion is constructed such that it allows the longitudinally transported flight structures of the article group selection and transport mechanism


32


to pass through angled conveyance lanes. As the flight structures mesh with and pass through the lane separator end portions, they engage articles disposed in lanes and rake them onto the longitudinal conveyance path of the mechanism.




Lateral and medial flap tuckers


62


and


64


are disposed adjacent each side of the carton transport mechanism, one


62


anterior to the loading region to provide a closed carton backside against which the loaded containers may nest and the other


64


posterior to the loading region to allow article group ingress to the carton through its open, unglued end flaps. Gluing, compression, and discharge mechanisms


66


are disposed further downstream and adjacent the carton supply and transport mechanism


30


to complete the carton flap securement process and form the fully formed, loaded cartons


22


.




Barrel Cam Loading Mechanism




The barrel cam loading mechanism


14


is synchronized with the aforementioned apparatus elements to move completed article groups traveling on the article group selection and transport conveyor


54


into aligned carton sleeves


24


traveling on the carton transport conveyor


58


. The barrel cam loading mechanism


14


basically comprises a plurality of loader arm assemblies


10


, a flight chain and guide tube assembly


72


to which the loader arm assemblies


10


are attached at predetermined intervals and that provides a longitudinal movement component thereto, and a control cam assembly


74


which provides a predetermined transverse motion component to the loader arm assemblies


10


. The flight chain and guide tube assembly


72


has a forward or top run


76


and a return or bottom run


78


and comprises drive and idler sprocket/shaft assemblies


80


and


82


and a pair of spatially parallel flight chains


84


which are connected to and revolve about the sprocket/shaft assemblies. The flight chains


84


are maintained in a rectilinear configuration on both the top and bottom runs by chain guides


86


, which are linked to the frame


38


via vertical support members.




Pairs of elongated guide tubes


88


are disposed at predetermined intervals along the flight chains


84


. The chains


84


are linked together by link pins


90


, a predetermined number of which extend and are sized to fit into the end openings


92


of the guide tubes


88


. Each guide tube


88


is directly connected at one end to the outer flight chain and at its opposite end to the inner flight chain so that they are oriented transversely with respect to the axis of the apparatus and to the downstream or forward run


76


of the barrel cam loading mechanism


14


. The guide tubes


88


have a low friction exterior surface to provide slidable support of the loader arm assemblies


10


. Each pair of closely spaced tubes


88


increase the stability of transverse movement of the arm


94


. Further stability is attained by guide passages


96


in a housing


98


and a guide block


100


. The spacing between successive sets (pairs) of tubes


88


corresponds to the spacing between the flight bars of the article group selection and transport conveyor


54


and between the flight lugs of the carton transport conveyor


58


so that the loader arm assemblies


10


are aligned to push product groups from between the flight bars into the carton sleeves


24


.




The loader arm assemblies


10


are movably mounted on the guide tubes


88


, and in a transverse orientation with respect to the axis of the cartoner


12


. Each loader arm assembly


10


basically comprises the arm


94


, which includes a base plate


102


and a loading head


104


located at one end of the base plate


102


, and further comprises the housing


98


and the guide block


100


. The arm assemblies


10


are conveyed in a downstream, longitudinal direction while the arms


94


simultaneously reciprocate in a transverse direction under the control of the control cam assembly


74


described below. A rotatable cam follower


106


cooperates with the cam assembly


74


to cause the arm


94


to transversely reciprocate on the guide tubes


88


and through the guide passages


96


of the housing


98


and the guide block


100


.




A transition conveyor is disposed between the barrel cam loading mechanism and the carton transport mechanism to provide a moving base for the movement of the article groups into the longitudinally conveyed carton sleeves


24


. A fixed dead plate may alternatively be used. The bottom member of the flight bars is elongated to extend across the top run of the transition conveyor to guide or funnel article groups across the conveyor and into the carton sleeves


24


between the carton end panels.




The control cam assembly


74


controls the transverse, reciprocal motion of the arm


94


in each loader arm assembly


10


, is generally oriented longitudinally with respect to the overall barrel cam loading mechanism


14


, and has a top or forward run


76


and a bottom or return run


78


. The top run


108


basically comprises an inwardly sloping approach segment


112


, an apex


114


, and an outwardly sloping return segment


116


. In the approach segment


112


the cam followers


106


, and thus the arms


94


, are urged inwardly and drive the loading head


104


of each arm


94


into moving engagement with a product group until it is loaded in a carton sleeve. A lag segment


118


of decreased slope is disposed at a predetermined point where the loading head


104


first contacts the article group to provide gentle, even pressure at this initial contact point. In the return segment


116


, the loading head


104


is retracted from the carton sleeve prior to its being reset in the return run


110


of the cam assembly


74


. The bottom or return run


110


of the cam assembly includes guide plates and a bottom cam rail which contacts the cam follower to further retract and reset the arms


94


for further loading cycles.




The forward run


108


of the cam assembly


74


comprises and outer rail


120


and an inner rail


122


that is spaced from the outer rail


120


a distance to form a pathway


124


adapted for receiving the cam followers


106


. The motion of the followers


106


in the cam pathway


124


effectuates transverse, inward motion to the housing


98


. The outer rail


120


of the cam


74


assembly may be connected to a pivot point at one end and to a release mechanism, such as a pressure release cylinder and piston, proximate its opposite end. The release mechanism is controlled by a sensing mechanism such as a photoeye or capacitive proximity sensor so that an excessive force placed on the outer rail due to a jamming of the arm assembly, for example, will actuate the release mechanism that in turn releases the outer rail to pivot away. This release mechanism design provides one means for detecting and relieving the pressure associated with a load jam. Another means is described in more detail below with respect to the barrel cam loader arm assembly


10


.




Barrel Cam Loader Arm Assembly




Referring to

FIGS. 7-14

along with

FIGS. 4-6

, each of the barrel cam loader arm assemblies


10


is connected to and longitudinally transported by the flight chain and guide tube assembly


72


and is further in operable contact with the control cam assembly


74


. Each loader arm assembly


10


generally comprises an arm


94


, a housing


98


, and a guide block


100


. The arm


94


includes a base plate


102


sized and shaped to be received by guide passages


96


formed in the housing


98


and guide block


100


, and further includes a loading head


104


attached to an inner end of the base plate


102


, and means for detecting a load jam described in more detail below. The base plate


102


is illustrated as having a rigid, flat, elongated structure that is oriented horizontally, and the loading head


104


is illustrated as having a single flat face member. Alternative designs are anticipated. As the arm assemblies


10


, particularly the arms


94


, move forward, the loading head


204


push the article groups forward from the article group selection transport conveyor


54


into the carton sleeves


24


. The loading head configuration may be modified for cartoning various other products and product group arrangements or configurations, including non-stacked and stacked configurations.




Both the housing


98


and guide block


100


include a body portion


142


and


130


with a pair of guide tube apertures


132


and a bushing


134


within each aperture


132


. The pair of guide tube apertures


132


are sized and arranged to slidably receive the pair of guide tubes


88


. Thus the housing


98


and guide block


100


provide the arm


94


with attachment means to the flight chain and guide tube assembly


72


, which provides longitudinal motion to the loader arm assemblies


10


. The housing


98


contacts and supports the base plate


102


near the outside end of the arm


94


, and the guide block


100


contacts and supports the base plate


102


near the inside end.




Referring to

FIG. 10

, the housing


98


further includes a cover portion


140


that is cooperatively attached to the body portion


142


. Both the cover portion


140


and the body portion


142


are formed with a channel


144


constructed and arranged to form the guide passage


96


when the cover portion


140


is attached to the body portion


142


. The cover portion


140


has a set of fastener apertures


160


and the body portion has a corresponding set of threaded fastener apertures


162


. Fasteners


164


are screwed through both sets of apertures


160


and


162


to securely fasten the cover portion


140


to the body portion


142


. Additionally, as illustrated in

FIG. 11

, the bottom of body portion


142


has a threaded cam follower aperture which is adapted to receive a threaded end of a rotatable cam follower


106


. The control cam assembly


74


contacts and influences the cam follower


106


, which in turn influences the housing


98


of the loader arm assembly


10


to move in a transverse, reciprocating motion.




Referring to

FIGS. 12-14

, the base plate


102


is either in a latch state


150


or in a slidable or release state


152


within the guide passage


96


of the housing


98


because of the means for detecting a load jam described below. In the latch state


150


, shown in

FIGS. 12-13

, the housing


98


holds and moves the arm


94


with it as it travels in the transverse, reciprocating motion. However, in the release state


152


shown in

FIG. 14

, the arm


94


will not move forward with the housing


98


, but will slide within the guide passage


96


of the housing


98


because of the force F associated with a load jam. Holding screws, not shown, may be turned into apertures


136


to prevent the base plate


102


from sliding out of the housing


98


.




The elements that comprise the means for detecting a load jam condition, or load jam detector, for the illustrated embodiment is described below. The top surface


170


of the base plate


102


of the arm


94


includes at least one concave depression


172


at a predetermined location, illustrated at the first end of the base plate


102


so that the housing


98


is near the edge of the first end when the arm is in the latch state


150


. The depression(s) have a predetermined size and shape. The cover portion


140


includes at least one threaded aperture


174


into which a plug


176


or set screw may be turned. The tip


178


of the plug(s)


176


has a rounded size and shape to cooperate with the size and shape of the depression(s)


172


, thus forming a detent. The tip(s)


178


remains seated within the depression(s)


172


when the arm


94


is in the latched state


150


, and is moved or forced from the depression(s)


172


and slides along the surface


170


of the base plate


102


when the base plate


102


of the arm


94


is in the released state


152


. Thus, the depression(s)


172


and plug(s)


176


function to provide means for the housing


98


to hold and move the arm


94


with the cam follower


106


in the latch state


150


and to release the arm


94


from moving with the cam follower


106


upon the detection or the application of a force F associated with a load jam and are considered means for detecting a load jam.




The number of depressions


172


and plugs


176


, the shape of the plug tip


178


and the shape and depth of the depression


172


, and the normal or holding force applied to the depression


172


that is adjusted by turning the plug


176


in the cover portion


140


all contribute the magnitude of the load jam force required to change the arm


94


from the latched state


150


to the released state


152


. Therefore, the sensitivity of this individual load jam detection feature can be adjusted to sense small load jam forces to prevent damage to delicate articles and cartons, or to sense larger load jam forces to enable sturdier article groups to be packaged into sturdier cartons without being overly sensitive to a load jam. It is anticipated that alternative arrangements of detent(s) and depression(s) may be used, and it is further anticipated that alternative means for providing an adjustable holding force may be used as well. Two depressions


172


and two plugs


176


are shown in the figures.




The descriptions above and the accompanying drawings should be interpreted in the illustrative and not the limited sense. While the invention has been disclosed in connection with the preferred embodiment or embodiments thereof, it should be understood that there may be other embodiments which fall within the scope of the invention as defined by the following claims. Where a claim, if any, is expressed as a means or step for performing a specified function it is intended that such claim be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof, including both structural equivalents and equivalent structures, material-based equivalents and equivalent materials, and act-based equivalents and equivalent acts.



Claims
  • 1. A loader arm assembly for use in a packaging system, comprising:(a) an arm; (b) a housing operably connected to at least one motive mechanism, said housing being adapted for moving said arm to load product into a package; (c) means for detecting a load jam condition, said arm having a latched state and a released state with respect to said housing, said arm normally being in said latched state to load product into said package, said arm entering said released state upon detecting said load jam condition, and said arm including a base plate and a loading head, said base plate having a first end and a second end, said first end of said base plate being latched to said housing when said arm is in said latched state, said base plate being adapted for sliding relatively with respect to said housing when said arm is in said released state, said second end of said base plate being connected to said loading head, said housing is formed with a guide passage adapted for receiving said base plate, said means for detecting a load jam includes at least one detent adapted for holding said base plate with respect to said housing in said latched state, and said at least one detent is formed by a tip of at least one plug extending through said housing to said guide passage, said tip being adapted for applying a holding force against said base plate, said first end of said base plate having at least one depression adapted for receiving said tip of said at least one plug in said latched state and for releasing said tip to slide on a surface of said base plate upon the application of a predetermined load pressure attributable to said load condition.
  • 2. The loader arm assembly of claim 1, wherein said at least one plug has threads and extends through a threaded aperture in said housing, whereby turning said at least one plug adjusts said holding force to either allow a smaller or require a larger load pressure to release said at least one plug tip from said at least one depression, and thereby providing said means for detecting a load jam with an adjustable sensitivity.
  • 3. The loader arm assembly of claim 1, wherein said housing comprises a body portion and a cover portion removably attached to said body portion, both said body portion and said cover portion having cooperating channels to form said guide passage.
  • 4. The loader arm assembly of claim 1, further comprising a guide block adapted for stabilizing said arm, said guide block having a guide passage adapted for slidably receiving said arm.
  • 5. The loader arm assembly of claim 1, wherein said at least one motive mechanism includes both a flight chain and guide tube assembly adapted for providing a longitudinal motion to said housing and a control cam assembly operably positioned with respect to said flight chain and guide tube assembly to provide a lateral motion to said housing, said flight chain and guide tube assembly including a parallel pair of flight chains and at least one guide tube connected to and extending between said flight chains, said housing having at least one guide tube aperture adapted for slidably receiving said at least one guide tube, said housing including a cam follower adapted for operably contacting said control cam assembly, said control cam assembly influencing said housing to laterally move along said at least one guide tube as said flight chain and guide tube assembly longitudinally transports said housing.
  • 6. A loader arm assembly for use in a continuous motion packaging system, comprising:(a) an arm including a base plate and a loading head, said base plate having a first end and a second end, said second end of said base plate being connected to said loading head; (b) a housing operably connected to a flight chain and guide tube assembly adapted for providing a longitudinal motion to said housing and to a control cam assembly operably positioned with respect to said flight chain and guide tube assembly to provide a lateral motion to said housing, said flight chain and guide tube assembly including a parallel pair of flight chains and at least one guide tube connected to and extending between said flight chains, said housing having at least one guide tube aperture adapted for slidably receiving said at least one guide tube, said housing including a cam follower adapted for operably contacting said control cam assembly, said control cam assembly influencing said housing to laterally move along said at least one guide tube as said flight chain and guide tube assembly longitudinally transport said housing and said arm in a longitudinal direction, said arm having a latched state and a released state with respect to said housing, said housing being formed with a guide passage adapted for receiving said base plate and for laterally moving said arm to load product into a package if said arm is in said latched state; and (c) at least one detent adapted for holding said base plate with respect to said housing in said latched state, said at least one detent providing said arm with both said latched state in which said arm moves laterally with said housing, and said released state in which said arm does not move laterally with said housing, said arm normally being in said latched state to load product into said package, said arm entering said released state upon detecting a load jam condition, said first end of said base plate being latched to said housing when said arm is in said latched state, said base plate being adapted for sliding with respect to said housing when said arm is in said released state.
  • 7. A loader arm assembly for use in a packaging system, comprising:(a) an arm including a base plate and a loading head, said base plate having a first end and a second end, said second end of said base plate being connected to said loading head, said first end of said base plate having at least one depression; (b) a housing operably connected to both a flight chain and guide tube assembly adapted for providing a longitudinal motion to said housing and a control cam assembly operably positioned with respect to said flight chain and guide tube assembly to provide a lateral motion to said housing, said flight chain and guide tube assembly including a parallel pair of flight chains and at least one guide tube connected to and extending between said flight chains, said housing having at least one guide tube aperture adapted for slidably receiving said at least one guide tube, said housing including a cam follower adapted for operably contacting said control cam assembly, said control cam assembly influencing said housing to laterally move along said at least one guide tube as said flight chain and guide tube assembly longitudinally transport said housing and said arm in longitudinal direction, said arm having a latched state and a released state with respect to said housing, said housing including a body portion and a cover portion removably attached to said body portion, both said body portion and said cover portion having cooperating channels to form a guide passage adapted for receiving said base plate and for laterally moving said arm to load product into a package if said arm is in said latched state; and (c) at least one plug extending through said cover portion to said guide passage, said at least one plug having a tip functioning as a detent adapted for holding said base plate to said housing and for releasing said base plate to slide with respect to said housing, said at least one plug providing said arm with both said latched state in which said arm moves laterally with said housing and said released state in which said arm does not move laterally with said housing, said arm normally being in said latched state to load product into said package, said arm entering said released state upon detecting a load jam condition, said tip being adapted for applying a holding force against said base plate, said at least one depression in said base plate being adapted for receiving said tip of said at least one plug in said latched state and for releasing said tip to slide on a surface of said base plate upon the application of a predetermined load pressure attributable to said load jam condition, said at least one plug having threads and extending through a threaded aperture in said cover portion, whereby turning said at least one plug adjusts said holding force to either increase or decrease said predetermined load pressure that is attributable to said load jam condition.
  • 8. A barrel cam loading mechanism, comprising:(a) a plurality of loader arm assemblies, each loader arm assembly including: (i) an arm; (ii) a housing including a cam follower, said housing having at least one guide tube aperture, said housing being adapted for moving said arm to load product into a package; (iii) means for detecting a load jam condition, said arm having a latched state and a released state with respect to said housing, said arm normally being in said latched state to load product into said package, said arm entering said released state upon detecting said load jam condition; and said arm includes a base plate and a loading head, said base plate having a first end and a second end, said second end of said base plate being connected to said loading head, said housing being formed with a guide passage adapted for receiving said base plate, said means for detecting a load jam including at least one detent adapted for holding said first end of said base plate with respect to said housing in said latched state, and said at least one detent is formed by a tip of at least one plug, said at least one plug having threads and extending through a threaded aperture in said housing to said guide passage, said tip being adapted for applying a holding force against said base plate, said first end of said base plate having at least one depression adapted for receiving said tip of said at least one plug in said latched state and for releasing said tip to slide on a surface of said base plate upon the application of a predetermined load pressure attributable to said load condition, whereby turning said at least one plug adjusts said holding force to either increase or decrease said predetermined load pressure that is attributable to said load jam condition; (b) a flight chain and guide tube assembly adapted for providing a longitudinal motion to said housing of each of said loader arm assemblies, said flight chain and guide tube assembly including a parallel pair of longitudinally oriented flight chains and at least one guide tube for each of said plurality of loader arm assemblies connected to and laterally extending between said flight chains, said guide tube having a slidable fit within said guide tube aperture of said housing, said plurality of loader arm assemblies being disposed along said flight chains at predetermined longitudinally spaced intervals; and a control cam assembly operably positioned proximate to said flight chain and guide tube assembly to provide a lateral motion to said housing of each of said loader arm assemblies, said control cam assembly influencing said housing to laterally move along said at least one guide tube as said flight chain and guide tube assembly longitudinally transports said housing.
  • 9. The barrel cam loading mechanism of claim 8, wherein said pair of flight chains extend about a drive shaft assembly and an idler shaft assembly to form a forward run and a return run, said flight chains comprising a plurality of links, adjacent links being connected together by a pin, said at least one guide tube having opposite end openings adapted to receive a pin from each of the pair of flight chains.
  • 10. The barrel cam loading mechanism of claim 8, wherein said control cam assembly has a predetermined approach segment for providing a constant rate of lateral extension to said arms throughout a majority of a total extension path of said arms, a predetermined apex for providing a complete extension of said arms toward said package, and a return segment for retracting said arm away from said package.
  • 11. The barrel cam loading mechanism of claim 8, wherein each of said loader arm assemblies further comprises a guide block adapted for stabilizing said arm, said guide block having a guide passage adapted for slidably receiving said arm.
  • 12. A barrel cam loading mechanism for use within a packaging system, comprising:(a) a plurality of loader arm assemblies, each loader arm assembly including: (i) an arm; (ii) a housing including a cam follower, said housing having at least one guide tube aperture, said second end of said base plate being connected to said loading head, said arm having a latched state and a released state with respect to said housing, said housing being formed with a guide passage adapted for receiving said base plate and for laterally moving said arm to load product into a package if said arm is in said latched state; (iii) at least one detent adapted for holding said base plate with respect to said housing in said latched state, said arm normally being in said latched state to load product into said package, said arm entering said released state upon detecting a load jam condition, said at least one detent being formed by a tip of at least one plug, said at least one plug having threads and extending through a threaded aperture in said housing to said guide passage, said tip being adapted for applying a holding force against said base plate, said first end of said base plate having at least one depression adapted for receiving said tip of said at least one plug and for releasing said tip to slide on a surface of said base plate upon the application of a predetermined load pressure attributable to said load jam condition, wherein turning said at least one plug adjusts said holding force to either allow a smaller or require a larger load pressure to release said at least one plug tip from said at least one depression; and (iv) a guide block adapted for stabilizing said arm, said guide block having a guide passage adapted for slidably receiving said arm; (b) a flight chain and guide tube assembly adapted for providing a longitudinal motion to said housing of each of said loader arm assemblies, said flight chain and guide tube assembly including a parallel pair of longitudinally oriented flight chains and at least one guide tube for each of said plurality of loader arm assemblies connected to and laterally extending between said flight chains, said guide tube having a slidable fit within said guide tube aperture of said housing, said plurality of loader arm assemblies being disposed along said flight chains at predetermined longitudinally spaced intervals; and (c) a control cam assembly operably positioned proximate to said flight chain and guide tube assembly to provide a lateral motion to said housing of each of said loader arm assemblies, said control cam assembly influencing said housing to laterally move along said at least one guide tube as said flight chain and guide tube assembly longitudinally transports said housing.
  • 13. A loader arm assembly for use in a packaging system, comprising:(a) an arm including a base plate and a loading head, said base plate having a first end and a second end; (b) a housing operably connected to at least one motive mechanism and being adapted for moving said arm to load product into a package, said housing comprising a body portion and a cover portion removably attached to said body portion, both said body portion and said cover portion having cooperating channels to form a guide passage adapted for receiving said base plate, said first end of said base plate being latched to said housing when said arm is in said latched state, said base plate being adapted for sliding relatively with respect to said housing when said arm is in said released state, said second end of said base plate being connected to said loading head; and (c) means for detecting a load jam condition, said arm having a latched state and a released state with respect to said housing, said arm normally being in said latched state to load product into said package, said arm entering said released state upon detecting said load jam condition.
US Referenced Citations (8)
Number Name Date Kind
3821874 Jones Jul 1974
4250693 Andersson Feb 1981
4802324 Everson Feb 1989
4936077 Langen et al. Jun 1990
4982556 Tisma Jan 1991
5036644 Lashyro et al. Aug 1991
5347796 Ziegler et al. Sep 1994
5388389 Tisma Feb 1995
Non-Patent Literature Citations (3)
Entry
Riverwood International Corporation, Illustration of a barrel cam loader-Side View (A).
Riverwood International Corporation, Illustration of a portion of a barrel cam loader-End View (B).
Riverwood International Corporation, Illustration of a portion of a barrel cam loader-End View (C).