Patent Document

CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims priority to U.S. application Ser. No. 60/676,458, filed Apr. 29, 2005, the entirety of which is incorporated herein by reference. 

   TECHNICAL FIELD 
   The invention relates to a conveying apparatus, and more particularly, to a stabilized and guided conveyor belt with multiple base chains and interchangeable conveyor plates. 
   BACKGROUND OF THE INVENTION 
   Articulated roller chain conveyors are commonly used in packaging applications to convey articles such as bottles or cans through a packaging machine to be loaded into paperboard cartons. It is often the practice to attach plates to the roller chain or to interlock plates to provide a smooth surface upon which the articles and/or cartons are conveyed. It is important to prevent the conveyor surface from tilting, buckling, or excessively undulating, which topples articles, interferes with other packaging machine components such as lane dividers, damages carton flaps, or otherwise causes misfeeds. This problem is exacerbated when accessories such as lugs are mounted to the plates to facilitate grouping or metering of articles. Each lug extends outward with respect to the surface of the plate to which it is mounted and increases the tendency of the plate to rotate about its longitudinal access (i.e., the lug increases the moment of the plate about a horizontal axis parallel to the direction of flow). Prior art lugs commonly shear off when exposed to these forces, as the lugs are often secured by two screws or pins disposed through the surface of the plate. The pins concentrate the reaction loads in singular areas of the plastic chain top, and thus, have the tendency to snap causing the lug to disengage. Such failures are costly, as the affected plate must be replaced or the broken screw or pins removed to mount another lug. It is desirable, therefore, to have plates that resist this moment and provide a stable surface regardless of whether accessories are mounted. 
   One prior approach that has been taken to reduce tilting, buckling, or excessive undulation of packaging machine conveyors involves running the transport chain under relatively high tension. This approach disadvantageously exposes the transport chain to increased wear and to elongation over time, particularly, as the transport chains are commonly constructed using links formed from plastic that are interlocked with steel pins. 
   Transport chains also typically comprise a single base chain disposed centrally with respect to the surface of the conveyor belt. Such single chain arrangements provide little resistance to rotational forces, and are more susceptible to stretching and other damage that can be caused by such forces as well as by typical operating conditions. 
   What is needed is a conveyor belt having a substantially flat, stable surface that resists tilting, buckling, and excessive motion. There is also a need for a durable transport chain that contributes to the stability of the conveyor belt without diminishing the efficiency of the machine. What is further needed is a conveyor plate upon which a grouping lug or other member can be securely mounted, and that is easily detachable for replacement or repair, or to reconfigure the conveyor belt. 
   SUMMARY OF THE INVENTION 
   The various embodiments of the present invention address the shortcomings in the prior art by providing a guided conveyor belt that is driven by a transport chain that utilizes dual steel base chains. The improved conveyor belt offers a smooth, substantially flat surface for conveying articles. Generally described, the surface of the conveyor belt is formed from multiple conveyor plates that can be easily attached independently of one another in a side by side fashion onto the transport chain and are readily detachable from the transport chain for replacement, repair, or reordering. The plates function selectively as a platform on which to mount accessories such as lugs and include means for receiving accessories and for locking accessories into place. The conveyor belt is guided and supported by a smooth rail. Both the belt and the rail include interacting stabilizing features that cooperate to prevent buckling and rippling of the conveyor belt, which also reduces stretching and other damage to the transport chain. 
   More specifically, each plate is preferably preformed of a somewhat elastically deformable material such as a plastic or other polymer. In the exemplary embodiments, plastic is injection molded to form the unitary structure of each plate, although any suitable means of manufacture that yields the structural and functional elements described herein will serve the objects of the invention. Suitable means of manufacture include, for example, alternative methods for manufacturing unitary plates such as thermoforming, pressure forming, low pressure foam molding, and vacuum forming. In alternative embodiments, the plate is formed from several components that may be different materials. For example, at least the upper surface of each plate may be formed from steel with the remainder of the plate being plastic. Accordingly, suitable means for manufacture also include twin sheeting or other methods for manufacturing and assembling plate structures formed from several components which are secured together using securing means such as adhesives and welds. A unitary structure is preferred in certain applications, however, to drastically reduce the cost of the plate and to increase part consistency. 
   The exemplary plate is configured as an attachment to be attached to an exemplary transport chain having dual base chains that translate power from a drive system. Each of the two base chains includes multiple links crafted from steel or a similarly strong and durable material. The links of each base chain are connected by hinge pins that protrude somewhat on either side of the links. In other embodiments, the transport chain includes more than two base chains. 
   The exemplary plate includes a body having a substantially flat top surface that is substantially rectangular in shape. The plate has side edges, end edges, and an underside from which an inside tab, an outside tab, and two central tabs extend. In alternative embodiments, such as where base chains are closely positioned, a single central tab extends from the underside of the plate. 
   According to one aspect of the invention, the tabs extending from the underside of each plate are configured to snap onto the dual base chains, and extend over the protruding portions of the hinge pins. The tabs include apertures through which the protruding portions of the hinge pins extend when the plate is attached to the dual base chains. Preferably, multiple plates are thereby secured to the transport chain with their sides disposed in relatively close proximity to one another and transversely with respect to the direction of travel. Thereby, the plates form a substantially continuous and flat conveyor belt on which the articles are conveyed. 
   According to another aspect of the invention, the conveyor belt, which includes at least in part the combination of the transport chain and the plates, is supported by and travels along a smooth rail. Specifically the rail guides the conveyor belt along a predefined path. The conveyor belt includes means for stabilizing each of the conveyor plates. The stabilizing means stabilizes the conveyor belt by limiting the movement of the conveyor belt with respect to the fixed rail. The exemplary conveyor belt has an outside edge and an inside edge, but is continuous, comprising an endless series of plates attached to an endless transport chain, although any suitable conveying configuration is contemplated, including a reversible belt having opposing ends. In the exemplary embodiments, a portion of each plate extends beyond the outside edge of the other components of the conveyor belt. 
   The stabilizing means includes a guide extending at an angle from both the inside tab and the outside tab. The guides extend outward toward the end edges of the plate so as to engage the edge of a flange extending from the rail. The guides prevent buckling and tilting of the belt along its length and width by restricting back and forth and side to side motion by further limiting the moment of the mounting plate even when the lug experiences cantilevered forces. 
   The use of multiple base chains is an important aspect of the invention, increasing the effectiveness of the support and stabilization features of the conveyor belt and rail. More specifically, the dual base chains of the exemplary embodiments are spaced apart, allowing the guides, outermost tabs, and sides of the rail to be spaced further apart, thereby decreasing the impact of moments and other forces caused by cantilevered loads on the conveyor surface. Each plate is stabilized indirectly against the moment about its transverse axis, which is parallel to the direction of machine flow, that tends to cause the belt to twist along its length. Further, each plate is stabilized directly against the moment about its longitudinal axis, which is perpendicular to the direction of travel, that tends to cause the belt to buckle. Thus, excessive and uneven wear and drag on the tabs, guides, and hinge pins is prevented, as is instability of the conveyor belt surface. 
   According to still another aspect of the invention, a portion of the underside or bottom surface of the body of each plate is substantially thinner and tapers in the direction of the outside edge of the conveyor belt. The slope of the bottom surface of the tapered portion defines an acute angle relative to the top surface of the tapered portion. The taper may be gradual or stepped. This tapering maximizes the thickness and strength of the nontapered portion of the conveyor belt, while providing a ledge over which articles slide into a carton and under which end flaps of cartons can pass. The tapered portion is flexible enough to maintain a degree of pressure on the carton flap below, where the pressure is generated by the articles resting on the upward facing surface of the tapered portion. In alternative embodiments, the taper is abrupt such that the tapered portion has a relatively uniform thickness, which is substantially less than the thickness of the rest of the body of the plate. Thus, as used herein, the word taper is expansively defined as to make thinner or narrower at one end or at both ends. 
   In certain embodiments, ribs are disposed on the underside of each plate to reinforce the plate so that the plate resists deformation caused by the weight of articles conveyed on the conveyor belt. Providing ribs rather than a thick dense plate achieves the objective of substantial rigidity while minimizing the material required for its construction. The reinforcing ribs preferably do not extend onto the tapered portion for at least the following two reasons. First, it is desirable for the tapered end of the plate to be somewhat flexible so that the plate can accommodate cartons having end flaps of different calipers. Second, ribs disposed on the surface of the relatively thin tapered portion of the plate would tend to cause the tapered portion to curl toward the underside of the plate, compromising the objective of a uniformly straight and flat conveying surface. 
   As mentioned above, the invention contemplates at least two types of plates—a blank plate for providing a conveyor surface, and a mounting plate that additionally receives one or more accessories that can be mounted thereon. The mounting plate includes a longitudinally disposed groove, its cross-section having a shape that is conducive to interlocking with a tongue having a complementary shape. As examples, the cross-section of the groove may be T-shaped, wedge-shaped, or L-shaped. The groove is configured to accept an accessory such as a lug that can be spaced apart from another lug mounted on another mounting plate, so as to meter articles such as bottles into groups of a predefined number. When mounted, the lugs are disposed transversely with respect to the direction of travel. Each lug includes a tongue having dimensions that provide a mating and interlocking fit as the tongue is guided into the groove. 
   The plates are attached to the transport chain independently of one another, such that the plates are not interlocked. Rather, the links of the base chains are interlocked preferably via the hinge pins, and the plates are then attached to the hinge pins. Independent attachment facilitates detaching and reordering of the plates to accommodate various grouping arrangements, carton sizes, packaging speeds, and other demands of the particular application in which the plates are used. 
   According to yet another aspect of the invention, means for receiving an accessory are provided so that the accessory can be coupled with the mounting plate. In the exemplary embodiments, means for receiving an accessory include the groove described above. The invention also provides means for locking or securing the accessory in place. In the exemplary embodiments, each lug is secured via a spring-loaded detent that is received in an aperture or depression disposed on the surface of the mounting plate. Lugs can be quickly installed or removed, but are less likely to shear off, because forces are distributed along the entire groove. 
   The foregoing has broadly outlined some of the aspects and features of the present invention, which should be construed to be merely illustrative of various potential applications of the invention. Other beneficial results can be obtained by applying the disclosed information in a different manner or by modifying the disclosed embodiments. Accordingly, other aspects and a more comprehensive understanding of the invention may be obtained by referring to the detailed description of the exemplary embodiments taken in conjunction with the accompanying drawings, in addition to the scope of the invention defined by the claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view of a conveyor belt showing an exemplary mounting plate, an exemplary lug member, and an exemplary base chain according to certain of the various embodiments of the invention. 
       FIG. 2  is a plan view of a segment of an exemplary conveyor belt showing a series of blank plates and mounting plates with lugs attached to certain mounting plates. 
       FIG. 3  is a side elevation view of a segment of the conveyor belt of  FIG. 2 , showing bottles disposed on the conveyor belt and grouped by the lugs. 
       FIG. 4  shows a cross-sectional view of an exemplary rail supporting an exemplary conveyor belt, showing the relationships between the mounting plate of  FIG. 1 , a lug, a transport chain, a carton conveyor, and the various flaps of a carton. 
       FIG. 5  is a perspective view showing the underside of the exemplary lug of  FIG. 1 . 
       FIG. 6  is a partial cross-section of the lug of  FIG. 1  mounted on an exemplary mounting plate, showing an exemplary means for securing the lug on the plate. 
       FIG. 7  is a plan view of the upper surface of the mounting plate of  FIG. 1 . 
       FIG. 8  is a side elevation view of the mounting plate of  FIG. 1 . 
       FIG. 9  is a bottom plan view, showing the underside of the mounting plate of  FIG. 1 . 
       FIG. 10  is an end elevation view, showing the tapered end of the mounting plate of  FIG. 1 . 
       FIG. 11  is an end elevation view, showing the blunt end of the mounting plate of  FIG. 1 . 
       FIG. 12  shows a cross-sectional view of an alternative rail supporting a conveyor belt including an alternative mounting plate having a lug mounted thereon. 
   

   DETAILED DESCRIPTION 
   As required, detailed embodiments of the present invention are disclosed herein. It will be understood that the disclosed embodiments are merely examples to illustrate aspects of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale, and some features may be exaggerated or minimized to show details of particular components. In other instances, well-known materials or methods have not been described in detail to avoid obscuring the present invention. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but as a basis for the claims and for teaching one skilled in the art to variously employ the present invention. 
   Referring now to the drawings in which like numerals indicate like elements throughout the several views, the drawings illustrate certain of the various aspects of exemplary embodiments of a stabilized conveyor belt with a guided transport chain and interchangeable conveyor plates. The various aspects of the invention are applicable to any of a variety of conveying applications, but for simplicity, the invention is described herein in the context of a packaging machine for loading articles into containers, such as paperboard cartons. 
     FIG. 1  is an exploded perspective view showing an embodiment of a conveyor plate according to the present invention. The plate shown is of the mounting type, and will hereinafter be referred to as mounting plate  100 . Mounting plate  100  is a unitary preformed plastic structure, although it can be fashioned using any system, method, and material for making a plate having the properties and components described herein. Mounting plate  100  includes a body  102 , several tabs  104  extending from the underside of the body  102 , and a top surface  106 , any or all of which are sufficiently deformable as to facilitate attachment to an exemplary transport chain by snapping into place. The exemplary transport chain comprises dual base chains  108  that include a series of chain links, including roller links  109   a ,  109   b  that are connected to one another by pin links  109   c . Specifically, hinge pins, which connect the plates of the pin links  109   c , extend through bushings, which connect the plates of the roller links  109   a ,  109   b , to interconnect the links  109   a ,  109   b ,  109   c , respectively. Rollers are disposed on each of the bushings of the roller links  109   a ,  109   b . The ends of the hinge pins extend outward from the sides of each of the base chains  108  or otherwise extend outwardly from the plates of the pin links  109   c.    
   Outside tab  122  and central tab  124  straddle one of the base chains  108 . Central tab  126  and inside tab  128  straddle the other base chain  108 . With a momentary reference also to  FIG. 12 , each of the tabs snap onto the adjacent base chain  108 , being secured by a pair of hinge pins with ends  118 ,  119 , and  120 ,  121  that protrude or otherwise extend from the sides of each of the base chains  108 . The body  102  and/or tabs  104  are deformable to facilitate snapping the mounting plate  100  onto the transport chain, thereby deflecting and then returning to its or their original shape or position after attachment. 
   Returning now to  FIG. 1 , those skilled in the art will appreciate that hinge pin ends  118  and  119  may comprise a single continuous pin that passes through the roller link  109   a , and hinge pin ends  120  and  121  may comprise a continuous pin that passes through the roller link  109   b . The pin ends  120 ,  121  extend at least partially through apertures or depressions  110 ,  112  when the mounting plate  100  is attached to base chain  108 . Apertures  111 ,  113 , obstructed in the figure, similarly receive hinge pins  118 ,  119  of base chain  108 . A second base chain (not shown) includes identical links and hinge pins that matingly attach to central tab  126  and inside tab  128  via apertures  114 ,  116 . Grooves  140  may be provided to facilitate guiding the hinge pins ends into registry with the respective apertures. Further, stabilizing means such as guides  130 ,  132  extend perpendicularly from respective outside and inside tabs  122 ,  128 , and a tapered section  142  of the body  102  is provided; all of which function as described below. 
   The mounting plate  100  includes means for receiving such as a longitudinal groove  134  that is disposed through or countersunk into the body  102  of mounting plate  100  to receive a matching tongue  504  (shown in  FIG. 5 ) portion of an exemplary lug member  136 . The groove  134  shown is a T-slot, although any suitable configuration of matching tongue  504  and groove  134  can be substituted. The receiving means also includes a depression  138  formed in or extending through the top surface  106  for receiving a detent  506  (shown in  FIG. 5 ) to detachably lock a lug  136  in place, as will be described in greater detail below. 
   A second type of conveyor plate is contemplated, and is shown in  FIG. 2  as blank plate  200 . As shown in the figure, the exemplary conveyor belt  202  comprises a series of conveyor plates attached to the transport chain, the series including a preferably regularly repeating pattern of various blank plates  200  and mounting plates  100  with lugs  136  attached to certain mounting plates  100 . In sum, each blank plate  200  is identical to each mounting plate  100 , except in that the blank plates do not have grooves  134  for receiving tongues  504  or depressions  138  for receiving detents  506 . Rather, a blank plate  200  serves as part of the conveyor belt surface, but can not receive a lug  136 . 
   The exemplary conveyor belt  202  has a longitudinal outside edge  206  and a longitudinal inside edge  204 , but is continuous, having no end edges. Conveyor belt  202  travels continuously in a direction of flow F, preferably forming a rounded rectangular path having a flat upper surface and rounded ends, although any conveyor configuration is contemplated, including reversible paths, and paths with serpentine or irregularly shaped courses. 
     FIG. 3  is a side elevation view of a segment of the conveyor belt  202 , with articles disposed on the conveyor belt  202 . The articles are shown as beverage bottles B, although the conveyor belt  202  could be used to convey any suitable type of article, including various types of foods and beverages in containers such as cans or boxes, as well as other conveyable products. The bottles B are grouped, spaced apart, and/or metered by the grouping lugs  136 , which ensure that a predefined number of articles are conveyed into cartons  400  ( FIG. 4 ) or other containers loaded by the packaging machine. 
     FIG. 4  shows a, cross-section of an exemplary conveyor belt  202 , showing the functional relationship between the mounting plate  100  of the present invention and other elements and articles associated with a loading station in the packaging machine. The mounting plate  100  is one of a series of plates  100 ,  200  attached side by side onto the dual base chains  108  of the transport chain. A grouping lug  136  is mounted onto the mounting plate  100 . As mentioned above, grouping lug  136  groups, spaces and/or meters several bottles B, which are to be loaded into an exemplary carton  400 . 
   Exemplary carton  400  is formed from a foldable sheet material such as paperboard, corrugated board, plastic, laminates, any combination thereof, or the like. To encourage an understanding of the various aspects of the invention, the construction of carton  400  will only be described only minimally. The foldable sheet material is typically provided as a unitary blank, which is partially assembled to form a collapsed tubular carton. In this collapsed state, the open-ended carton can be fed into the packaging machine, where the carton  400  is partially erected and placed on a carton conveyor, which is described in greater detail below. In the exemplary embodiments, one end of the carton is then sealed. At the loading station, articles such as bottles B are grouped and loaded through the open end of the carton  400 , and the end flaps  414  and  416  (not shown) and end flaps  410  and  412  are folded and secured together to form an end closure structure (not shown). 
   The conveyor belt  202  transports the bottles B in a direction of machine flow F along a container path through the loading station, a portion of which is represented by  FIG. 4 . The carton conveyor positioned parallel to the container conveyor  202  simultaneously transports cartons  400 , each being disposed on its bottom wall (not shown), along a carton path that follows the same direction of machine flow F, where the direction of flow F is normal to the plane of the figure. For example, the carton  400  is placed on the carton conveyor such that its side walls  404  are substantially perpendicular to the direction of machine flow F and top wall (not shown), which is substantially parallel to the direction of machine flow F. 
   The surface of the carton conveyor is formed of at least one conveyor chain top  402 . The conveyor chain tops  402  may be attachments having tabs  406  that are attached to a transport chain comprising base chains  408 . To reach the carton  400 , the bottles B may have to cross a transition plate  418  that separates the conveyor belt  202  from the carton conveyor. The conveyor belt  202  moves at the same or at a complementary speed as the carton conveyor during the loading process, driven by transport chain (base chains  108 ). 
   The conveyor belt  202  is supported and stabilized by a rail  420 , which is formed from a smooth material that will impart a relative low degree of kinetic friction to the material from which the plates  100 ,  200  are constructed. A low coefficient of friction between the materials allows the rail  420  to support and guide the plates  100 ,  200  as the conveyor belt  202  is driven by the transport chain, without producing drag that would impede the free movement of the conveyor belt  202 . In the embodiments described herein, the rail  420  is made of an extruded reinforced plastic material. Those skilled in the art will appreciate that a plethora of known plastic materials, as well as other materials, may offer the performance characteristics required of the rail  420  and related elements. Because the conveyor belt  202  is supported by the rail  420  and not by the base chains  108 , the forces generated by the drive are concentrated, via the transport chain, on imparting motion to the conveyor belt  202 . Thus, the efficiency of the drive system is increased, and the wear or the components of the conveyor belt  202 , base chains  108 , and rail  420  is reduced. 
   To support the conveyor belt  202 , the rail  420  includes supports  422   a ,  422   b  upon which portions of the underside of the plates  100 ,  200  rest. More specifically, support  422   a  supports the outside end of the plates  100 ,  200  and support  422   b  supports the inside end of the plates  100 ,  200 . It should be noted that, for the most part, the tapered portion  142  does not contact the rail  420 , and rather, overhangs and extends beyond the rail  420  and toward the transition plate  418  and/or the carton conveyor. 
   To stabilize the conveyor belt  202 , flanges  424   a ,  424   b  extend toward one another and away from supports  422   a ,  422   b  so as to engage respective guides  130 ,  132  and the outside and inside tabs  122 ,  128 . This mating arrangement between the flanges, guides, and tabs eliminates the tendency of the belt to roll from edge to edge or to otherwise twist or buckle. Each guide  130 ,  132  extends away from the respective outside and inside tab  122 ,  128  to fit securely underneath the flange  424   a ,  424   b . As is best shown in  FIG. 9 , each exemplary tab  122 ,  128  is substantially as wide as the plate  100 , and each guide  130 ,  132  is substantially as wide as the width of the respective tab  122 ,  128 . Although the relative widths may vary in other embodiments, stability about the longitudinal axis of the exemplary plate  100  is improved because the guides  130 ,  132  are sufficiently wide to engage a significant longitudinal portion of the respective flange  424   a ,  424   b  to resist any moment generated by cantilevered forces. 
   Returning to  FIG. 4 , additional support and guidance for the plates  100 ,  200  is provided by one or more crossbar portions  426   a ,  426   b  of the rail  420 . In the embodiment shown, two crossbars  426   a ,  426   b  are provided, each supporting and/or guiding the bottom surfaces of the respective guides  130 ,  132 . In alternative embodiments, a single continuous crossbar that extends between supports  422   a  and  422   b  is provided, but this arrangement uses more material as the most useful portions of a single crossbar are those disposed directly beneath the guides  130 ,  132 . Referring momentarily to  FIG. 12 , in another alternative embodiment that is described in greater detail below, ledges  1256   a  and  1256   b  support the underside of guides  1230 ,  1232 . 
   The fit between the tabs, guides, supports, flanges, and crossbars is mating so as to prevent unwanted motion such as buckling and rippling, but there is preferably enough latitude to ensure free movement of the conveyor belt  202  and to prevent seizing. The tabs and guides are flexible enough to yield as needed to seat the conveyor belt  202  in the channel defined by the supports, flanges, and crossbars without flexing so much as to undesirably detach from the transport chain. 
   The rail  420  is sturdy enough to withstand forces generated by supporting the weight of the bottles B or other products carried on the conveyor belt  202 . The rail  420  includes an extruded aluminum core beam  430  that provides support and reinforcement along the length of the conveyor. The core beam  430  includes voids for matingly receiving locking members  428 ,  429  of the rail  420 . 
   Prior to each carton  400  entering the loading station, the distal end portion of the lower end flap  412  is guided by an end flap guide (not shown) into the position under the plates  100 ,  200  of the conveyor belt  202  to travel along with the plates  100 ,  200 . This allows the remainder of the lower end flap  412  to be slidably held on and extended across the bridge plate  418  so that the lower end flap  412  is capable of supporting the bottles B that come off of the conveyor belt  202  and guiding them into the carton  400 . 
   At predefined points during the loading process, each group of bottles B is urged off the outside edge  204  of the conveyor belt  202 , across the transition plate  418  between the conveyor belt  202  and the carton conveyor, and toward the open end of the carton  400  that is transported on the carton conveyor. The transition plate  418  may include a stationary or mobile element that is disposed between the conveyor belt  202  and the carton conveyor, such as the upper surface of a bridge panel. The transition plate  418  separates the moving parts of the conveyor belt  202  and the carton conveyor, and provides an upper surface for supporting the end flap  412  of each carton while the bottles B are urged into the carton  400  and slide across the end flap  412 , thereby traveling across the transition plate  418 . The transition plate  418  also guides the end flap  412  so that the distal end portion of the end flap  412  is placed under the tapered portion  142  of the plates  100 ,  200  while each carton moves through the loading station. In other words, at the loading station, end flap  412  extends across the transition plate  418 , its distal end being disposed beneath the conveyor belt  202 . Thus, the maximum width of the transition plate  418  is substantially equal to the distance between the carton conveyor and the upper surface  106  of plates  100 ,  200  comprising conveyor belt  202 . 
   As previously mentioned, the present invention encompasses means for securing the lug  136  on the mounting plate  100 . In the exemplary embodiments, mounting plate  100  includes a groove  134  that is configured to receive the exemplary grouping lug  136 .  FIG. 5  shows the underside of grouping lug  136 , which includes a tongue  504  having a cross-sectional shape and dimensions that correspond to the shape and dimensions of the groove  134 , so as to create an interlocking joint therebetween. The exemplary tongue  504  has a shape that is similar to an uppercase letter T, and the groove  134  has a shape that is similar to an inverted uppercase letter T, although any corresponding shapes could be used, including but not limited to, the mortise and tenon shape of a dovetail joint. The lug  136  is detachably locked into place via a detent assembly including a spring-loaded detent pin or ball  506  that is housed in recess  508 . The detent pin  506  corresponds to the aperture or depression  138  in the mounting plate  100 . 
   The tongue  504  includes a stem  514  that is narrower than the uppermost portion of groove  134 , and two flanges  510  and  512  that are captured by legs  1106  (shown in  FIG. 11 ) of the groove  134 . The height of the stem is at least as great as the thickness of the legs  1106 , and the thickness of the flanges  510 ,  512  is no greater than the height of the side walls  1102  (shown in  FIG. 11 ) of the groove  134 . To mount lug  136  as shown in the cross-section view of  FIG. 6 , flanges  510 ,  512  are trapped beneath legs  1106  while sliding the outside end  516  of the lug  136  toward the tapered end of the mounting plate  100 . When the detent pin  506  is in registry with depression or aperture  138 , the lug  136  locks into place. 
   As  FIG. 7  shows, portions of the groove  134  may extend completely through the body  102 , creating a gap that reveals upper edges of the tabs  104  that extend from the underside of the mounting plate  100 . Alternatively, the groove  134  may be only a longitudinal trench having a bottom surface  1104  ( FIG. 11 ), or a combination of a gap and a trench. Referring to  FIGS. 8 and 9 , in the embodiments shown, the aperture  138  extends completely through the body  102  as well, although a depression sufficient to detachably engage the detent pin  506  can be used instead. Whether an aperture or depression, element  138  can have any shape that corresponds to the shape and dimensions of the detent pin  506 . 
   Referring now to  FIG. 9 , the underside of the body  102  of mounting plate  100  and blank plate  200  may include longitudinal ribs  902  that extend from the inside end  904  of the plate  100 ,  200  and terminate prior to reaching the outside edge  906 . Preferably, the ribs  902  do not extend onto the tapered portion  142  of the plate  100 ,  200  so as not to interfere with the passage of the lower end flaps  412  of the cartons  400 . The ribs  902  increase the longitudinal strength of the plate  100 ,  200 , countering any tendency to bow or arch along the length of plate  100 ,  200  due to irregular load distributions that may occur as articles are urged off of or onto the edges  204 ,  206  of the conveyor belt  202 . The ribs  902  provide a favorable alternative to achieving the necessary strength by increasing the overall thickness of the plate  100 ,  200 , which would consume more material and increase the weight of the plate  100 ,  200 . As shown in  FIGS. 10 and 11 , the innermost ribs  902  may also function as side walls  1102  of at least a portion of the groove  134 . 
     FIGS. 10 and 11  make apparent that in the exemplary embodiments, the apertures  110 ,  111 ,  112 ,  113 ,  114 ,  115 ,  116 ,  117  extend through the respective tabs  122 ,  124 ,  126 ,  128 . In alternative embodiments, depressions for receiving hinge pin ends  118 ,  119 ,  120 ,  121  are provided, the depressions extending only partially through the respective tabs  122 ,  124 ,  126 ,  128 . 
     FIG. 12  shows a cross-sectional view of an alternative rail  1250  supporting a conveyor belt including an alternative mounting plate  1200  having a grouping lug  136  mounted thereon. The mounting plate  1200  differs from the mounting plate of  FIGS. 1 through 11  in that the thickness of the body  1208  at the side edges is comparatively reduced. The groove  1234  (not shown) is defined in part by side walls  1202  and may or may not have a bottom surface. In certain versions of this embodiment, longitudinal ribs (not shown) are also included. 
   Notably, the rail  1250  includes supports  1252   a ,  1252   b  and flanges  1254   a ,  1254   b , but does not include crossbars. Rather, notches are removed from supports  1252   a ,  1252   b  below the flanges  1254   a ,  1254   b , thereby defining ledges  1256   a ,  1256   b , which support the respective tabs  1230 ,  1232 . Locking members  1258   a ,  1258   b  are also provided to secure the rail  1250  to an inner core beam (not shown). 
   It should be noted that the transport chain, as described herein, may be any continuous drive system to which a conveyor plate may be attached to form a conveyor belt. For example, the transport chain may include all types of chain that is known or yet to be invented, chain with attachment links, belts, and the like. In addition, means for mounting the conveyor plate to the transport chain is not limited to tabs which attach to hinge pins extending from base chains. It is considered that the tabs may be adapted such that they attach to the plates of the links of the transport chain. 
   The present invention has been illustrated in relation to a particular embodiment, which is intended in all respects to be illustrative rather than restrictive. Those skilled in the art will recognize that the present invention is capable of many variations and combinations without departing from the scope of the claims appended hereto and supported by the foregoing. 
   Those skilled in the art will also appreciate that the packaging machine described represents only one example of the various packaging machine types and configurations that will be suitable for implementation of the various embodiments of the invention. Furthermore, the advantages of the invention can be realized in any conveying application or process, without limitation to the packaging arts.

Technology Category: b