Abstract:
An automated conveyor sortation and item discharge system for sorting items of various sizes and weights to designated output destinations along a conveyor is provided. The system utilizes a discharge drum ejection mechanism mounted medially between a pair of parallel cog belt conveyors for ejecting an item such as a parcel laterally from the surface of the cog belt conveyors to an adjacent chute or slide. The discharge drum of the ejection mechanism is generally rectangular and defines convex opposing sides separated by the longer diameter of the drum. The convex sides of the discharge drum define flexible ridges for contacting an overlying parcel to be discharged from the surfaces of the cog belt conveyors. The flexible ridges enhance translation of the item or parcel by the discharge drum and serve to reduce noise caused by the impact of the discharge drum with the overlying parcel. A tapered discharge drum may be used to counteract rotation of the parcel during discharge. A programmable controller may be provided to control the conveyor system and the discharge of items from the conveyor by the ejection mechanisms. The system is easy to repair and operates at high speeds at reduced noise levels. Also provided is a relatively flat disc intermediate a conveyor gap, which may be disassembled without disturbing the shaft to which the disc is mounted.

Description:
CROSS-REFERENCE TO EARLIER-FILED APPLICATION 
     This application is a continuation-in-part of a previously-filed application Ser. No. 08/841,201, filed Apr. 29, 1997, entitled “High Speed Drum Sorting Conveyor Systems”. 
    
    
     TECHNICAL FIELD 
     This invention relates to automated sorting of items such as parcels to a variety of output destinations, and more particularly relates to conveyor systems which have the capability to rapidly and reliably discharge parcels (which can also be referenced as packages) or other items thereon to either side of a conveying path, such that the packages or other items may be transported elsewhere. 
     BACKGROUND OF THE INVENTION 
     In modern high volume package delivery systems, package delivery services utilize a variety of material handling systems. Such material handling systems often include package conveying systems that divert packages to a variety of output destinations such as chutes, bins, and conveyor systems. 
     One of the most conventional types of conveyors is a belt conveyor, which includes the use of an endless flexible belt which passes over at least two cylindrical rollers, one of which is a drive roller. Packages are placed atop the upwardly-directed “working” surface of the belt conveyor, and are transported in a generally straight direction from end of the conveyor to the other. Another type of conveyor is a “roller” conveyor which con include powered or idling rollers which contact, support, and in certain instances propel the bottom of the package along its path. 
     Systems for diverting objects from a moving conveyor have been available for many years. Such systems are useful in discharging objects from a conveying surface at selected stations located along the path of the conveying surface. 
     Some package diverting systems utilize a pusher element or member mounted on or beneath a conveying surface which when actuated ejects a package laterally across the conveying surface to a desired discharge station. Many such systems guide a pusher element laterally across the conveying surface using a complex series of guide tracks, or elements mounted beneath the conveying surface. Other systems utilize a means for elevating and tilting a package above and away from the upper surface of a conveying surface so that the package may be withdrawn to an awaiting chute or discharge station. Still other systems have been known to collapse the conveying surface such that the package falls to a subjacent conveying surface on which the package is translated to a desired discharge location. 
     U.S. Pat. No. 1,462,511 discloses another conveyor diverter. A side conveyor extends perpendicular from a main conveyor. A set of diverting rollers are configured perpendicular to the main conveyor and are raised above the upper surface of the main conveyor to cause an object to be diverted from the surface of the main conveyor under force of gravity across the set of diverting rollers. 
     U.S. Pat. No. 1,549,499 discloses an elevating means for use in connection with roller bed sorting tables for raising a box or parcel a slight distance above the plane of the roller bed to allow the box or parcel to be withdrawn to an awaiting chute or discharge station. A box or parcel to be discharged is brought to a state of rest at a sorting station immediately above an elevating roller. The elevating roller is raised by depressing a foot lever. The box or parcel positioned over the elevating roller is raised off the roller bed which allows an operator to pull the box or parcel off the roller bed on to an adjacent chute or discharge station. 
     A box or parcel switching unit for discharging a box sideways on to an adjacent storage conveyor or chute is disclosed in U.S. Pat. No. 2,062,604. A box or parcel is brought to a stopped position on a receiving conveyor and overlying a discharge conveyor. The receiving conveyor is dropped from beneath the box or parcel allowing it to come to rest on the discharge conveyor. The box or parcel is then translated off the surface of the discharge conveyor to an awaiting adjacent conveyor or chute. 
     U.S. Pat. No. 3,138,238 discloses a conveyor system with a powered diverter for diverting an object from the surface of a main conveyor to an awaiting side conveyor. The powered diverter includes an assembly of diverting wheels that are oriented toward the side conveyor. The group of diverting wheels are normally positioned below the upper surface of the main conveyor so that objects traveling on the main conveyor do not contact the diverting wheels. In order to divert an object from the main conveyor to the side conveyor, the diverting wheels are elevated so that they are slightly above the upper surface of the main conveyor. Accordingly, an object traveling down the main conveyor is diverted by contact with the elevated diverting rollers. 
     U.S. Pat. No. 3,291,279 to DeGood likewise discloses a conveyor system with a powered diverter, which as shown in FIG. 8 works in conjunction with a shifting linkage  200 . Chains of powered roller elements are used, which are indexed upwardly to engage packages to eject them at an angle from the original conveying path. 
     U.S. Pat. No. 3,303,923 to Davis discloses a conveyor diverter mechanism which includes a number of relatively thin conveying belts  25 ,  26 , and  27  which are indexed upwardly as shown in FIG. 2 to engage and withdraw a selected package. 
     U.S. Pat. No. 4,598,815 to Adama discloses a powered roller diverter which includes a single row of powered diverter rollers which can be selectively indexed upwardly to engage and eject a package on a belt conveyor path. The single row of diverter rollers is selectively indexed upwardly from within a transverse gap between the downstream roller of an upstream conveyor to the upstream roller of a downstream conveyor, such that the rollers engage and discharge a package sidewardly. 
     U.S. Pat. No. 4,730,718 to Fazio discloses a ‘bi-directional mechanism” which, as shown well in FIG. 1, shows a plurality of elastomeric belts  76  mounted upon an indexable table assembly associated with a conveyor assembly. The belts are supported by indexable rollers such that portions of the belts can be indexed upwardly within elongate slots defined between elongate conveyor rollers being part of the conveyor assembly, to cause the belt portions to engage packages otherwise atop the conveyor rollers, and to eject them to either side of the conveyor path. The Kloosterhouse patent (U.S. Pat. No. 4,962,841), owned by the same assignee, likewise discloses such a configuration. 
     U.S. Pat. No. 4,979,606 to Usui discloses a transporting direction controlling device applicable to conveyor systems. As shown in FIGS. 1-5 of the Usui patent, the device utilizes a rotor member comprised substantially of a cylindrical or disk-shaped roller which is tiltable in variable directions for tilting the plane of the upper surface of the rotor member. By tilting the direction of the plane and the rotating direction of the rotor member, the transporting direction of a box or package may be changed. As shown in FIGS.  3 (A)- 3 (D) of Usui, force is exerted on an object by tilting the plane of the rotating device so that the object will be moved in the direction tangent to the direction of travel of the upper most portion of the tilted rotating device. In practice, Usui describes using the rotating device in concert with a plurality of similar rotating devices to form a direction changing station, as shown in FIGS. 5 and 12. As shown in FIGS. 6 and 21, guide plates  116 ,  118 , and  312  are used to define a direction change path for the object. 
     U.S. Pat. No. 5,165,516 to Reed discloses a three-way transfer conveyor which includes transfer belts which are selectively driven to the left and to the right at right angles to the conveyor rollers. As in the Fazio and Kloosterhouse references, the rubber belts fit into elongate transverse “gaps” between the conveyor rollers. 
     In some of those systems, diverter mechanisms are utilized to divert an object from the upper surface of a conveying surface by bringing the object to a complete stop overlying the diverter mechanism and then either raising the diverter mechanism or lowering the object so that the diverter mechanism comes into contact with the object. Bringing the object to a complete stop prior to being diverted causes a significant reduction in the efficiency and speed of operation of the conveyor system. Some of those systems move a diverter into the path of a moving object. Problems associated with those systems include the inability to eject objects laterally from the surface of a moving conveying system at ejection speeds which are independent of the speed of the moving conveyor system. 
     Other limitations in the prior art include an inability to eject objects laterally at a high speed without encountering rotation of the package or object as it is discharged from the surface of the moving conveyor. Furthermore, such systems may be noisy and relatively difficult to repair when diverter systems components fail. 
     Finally, some prior art systems are complex in construction and require substantial disassembly in order to replace the discharge elements should they wear out. 
     Thus, there is a need in the art for a sorting conveyor system that can discharge or eject an object from a conveying surface without bringing the object to a stop and without changing the position or speed of the conveying surface. There is also a need in the art for a sorting conveyor system that can discharge or eject an object from a conveying surface at high speeds and without undesired rotation of the object during discharge. There is further a need in the art for a sorting conveyor system that is quiet during operation and which is easily repaired. Finally, there is a need in the art for a conveying device which allow for quick changes of replacement parts in order to reduce downtime. 
     SUMMARY OF THE INVENTION 
     The present invention seeks to provide an improved system for efficiently discharging items of various sizes and weights from a moving conveying surface. The present invention allows an object to be discharged laterally from the surface of a moving conveyor independent of the speed of the moving conveyor. An object may be discharged without raising an object diverter or ejection mechanism into the path of the moving object and without lowering the conveying surface to allow a moving object to contact a subjacent object diverter or ejection mechanism. The present invention is simple in construction and may be easily maintained by the quick removal and substitution of failed components. 
     Generally described, the present invention comprises a conveying and diverting apparatus for selectively discharging conveying parcels having a lower surface from a conveying path, the conveying and diverting apparatus comprising a conveyor defining an elongate gap transverse to the path, and a substantially planar disc configured for extending upwardly through the gap to contact the lower surface of the parcels, the disc being powered to eject a parcel with a force lying substantially parallel to said gap. 
     More particularly described, the present invention comprises a conveying and diverting apparatus for selectively discharging conveying parcels having a lower surface from a conveying path, the conveying and diverting apparatus comprising a conveyor defining an elongate gap transverse to the path, the conveyor including at least one conveyor belt assembly defining one edge of the gap, and a substantially planar disc configured for extending upwardly through the gap to contact the lower surface of the panels, the disc being powered to eject a parcel with a force lying substantially parallel to said gap. 
     The present invention also provides a conveying and diverting apparatus for selectively discharging conveying parcels having a lower surface from a conveying path, the conveying and diverting apparatus comprising a conveyor configured for conveying parcels along the conveying path by supporting the lower surfaces of the parcels, the conveyor defining an elongate gap transverse to the path, a substantially planar disc rotatably mounted about an axis substantially parallel to the conveying axis, the disc having a substantially round periphery except for a peripherally reduced portion, means for rotatably mounting the disc relative to the conveyor gap such that when the disc is at a first rotational position, the disc interferes with the parcels in the conveyor path, but when the disc is at a second rotational position, the disc does not interfere with the parcels in the conveyor path, and means for selectively rotating the disc from the first to the second rotational position, such that parcels on the conveyor may be correspondingly selectively discharged from the conveying path upon rotation of the disc timed to contact of the round periphery portion with the lower surfaces of the parcels and to discharge the parcels. 
     The present invention also provides a conveying and diverting apparatus for selectively discharging conveying parcels having a lower surface from a conveying path, conveying and diverting apparatus comprising a conveyor configured for conveying parcels along the conveying path by supporting the lower surfaces of the parcels, the conveyor defining an elongate gap transverse to the path, a substantially planar disc rotatably mounted about an axis substantially parallel to the conveying axis, the disc having a substantially circular periphery, a disc supporting shaft substantially rigidly attached to and supporting the disc, means for rotatably mounting the disc supporting shaft relative to the conveyor gap along an indexing rotational axis such that the when the disc is at a first indexed position, the disc interferes with the parcels in the conveyor path, but when the disc is at a second indexed position, the disc does not interfere with the parcels in the conveyor path, and means for selectively indexing the disc supporting shaft about is longitudinal axis while the disc supporting shaft is rotating, such that parcels on the conveyor may be correspondingly selectively discharged from the conveying path upon the indexing of the disc supporting shaft which causes the disc to contact the lower surfaces of the parcels and to discharge the parcels. 
     Finally, the present invention, an apparatus for conveying articles, the apparatus comprising a first conveyor portion, second conveyor portion spaced from the first conveyor portion so as to define an elongate gap therebetween, an ejection disc configured for extending through the gap and the conveyor, a disc supporting shaft for supporting the disc, and shaft rotating means for rotatably driving the supporting shaft, the ejection disc being configured to be removed from the disc supporting shaft without disengaging the shaft rotating means from the shaft. 
     Therefore, it is an aspect of the present invention to provide an improved automated conveyor sorting system. 
     It is a further aspect of the present invention to provide an improved ejection mechanism for ejecting items from a conveying surface. 
     It is a further aspect of the present invention to provide a conveyor which is simple in construction. 
     It is a further aspect of the present invention to provide a conveyor which is reliable in construction. 
     It is a further aspect of the present invention to provide a conveyor which is simple in operation. 
     It is a further aspect of the present invention to provide a conveyor which is cost-effective to manufacture, operate, and maintain. 
     It is a further aspect of the present invention to provide an improved conveyor which may be easily dismantled for repair and maintenance. 
     It is a further aspect of the present invention to provide an improved apparatus for conveying and sorting items that can be repaired by quickly removing failed sub-assemblies. 
     It is a further aspect of the present invention to provide a conveyor which operates at reduced noise levels. 
     Other aspects, features, and advantages of the present invention will become apparent upon reading the following detailed description of the preferred embodiment of the invention when taken in conjunction with the drawing and the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top plan view of an automated sorting system embodying the present invention. 
     FIG. 2 is a side diagrammatic view of the automated sorting system of FIG.  1 . 
     FIG. 3 is a side diagrammatic view of a cog belt conveyor system showing a self-tensioning gear motor drive system. 
     FIG. 4 is an end view of part of the gear motor drive system of FIG.  3 . 
     FIG. 5 is a side elevation view of a portable gear motor mounted on a wheeled table. 
     FIG. 6 is an end view of a discharge drum ejection mechanism of the present invention. 
     FIG. 7 is an end view of the discharge drum ejection mechanism of FIG. 6, showing a parcel being discharged to a discharge chute. 
     FIG. 8 is a top plan view of a discharge drum of the present invention. 
     FIG. 9 is a top plan view of a roller bed sorting system embodying the present invention. 
     FIG. 10 is a top plan view of a tapered discharge drum of the present invention. 
     FIG. 11 is a transaxial cross-sectional view of the tapered discharge drum of FIG.  10 . 
     FIG. 12 is a top plan view of a portion of a conveyor system according to the present invention, illustrating an ejection disc  100  located between upstream and downstream conveyor belt assemblies  120 ,  121 , respectively. A parcel  12  (also known as a package  12 ) is shown approaching the ejection disc  100 . If the ejection disc  100  ejects the parcel  112 , the parcel will be urged into the area of a side chute  114 . If the ejection disc  100  does not eject the parcel  112 , the parcel will be passed from upper conveyor belt assembly  120  to lower conveyor belt assembly  121 . 
     FIG. 13 is an “upstream” illustrative sectional view of the configuration of FIG. 12, looking along the conveying axis, showing an ejection disc  100  ejecting a package to the viewer&#39;s right. The ejection disc  100  is shown in round solid line outline, although as shown by the dotted line a flat spot  102  is included which exists if a truncated section is provided as discussed later. 
     FIG. 14 is a side elevational view of a portion of a conveying configuration according to the present invention. A package  212  is moved from conveyor belt assembly  220  to a downstream conveyor belt assembly  221 . As may be seen, the two conveyor belts include substantially planar upper conveying surfaces, which lie substantially along the same horizontal plane. A first embodiment of an ejection disc  200  is positioned intermediate the two belts, and is configured such that its selective rotation causes a portion of the disc to be moved upwardly into the path of the package (preferably from below the package), such that the package is discharged sidewardly relative to the two conveying belts. 
     FIG. 15 shows an isolated view of the 12″ diamater ejection disc  200  as viewed from its downstream side and a flat section  202 . As may be seen, when the ejection disc  100  is in its normal position, the flat section allows passage of the package. However, when the ejection disc  200  is rotated, the curved peripheral edge  201  of the ejection disc  100  rises above the conveying surface, causing interference with a package moving along its conveyor path and preferably discharging the package. 
     FIGS. 16 and 17 are views similar to FIGS. 14 and 15, respectively illustrate what happens when the ejection disc is rotated 180 degrees about its rotational axis from that shown in FIGS. 14 and 15. As may be seen, when the ejection disc  200  is actuated through such rotation, its curved edge (having a grip surface) rises above the conveyor surface, causing the package to be lifted. As the ejection disc  200  is likewise rotating, this engagement causes the package to encounter a force substantially 90 degrees in relation to the conveying axis of the package. 
     FIG. 18 is a side elevational view of a second disc embodiment of the present invention, illustrating a parcel  312  being passed from an upstream conveyor belt assembly  320  towards a lower conveyor belt assembly  321 . An ejection disc  300  is shown contacting the underside of the package  312 , being indexed upwardly by use of an actuator  340 , which actuates a pivoting support member  333 , which supports a motor  330 , which rotatably drives a shaft  331 , which is substantially rigidly attached to the ejection disc  300 . 
     FIG. 19 is a view similar to that to FIG. 18, except no package is shown, and the ejecting disc  300  is in its “neutral” or “withdrawn” position. 
     FIG. 20 is a side elevational view illustrating a first multi-segmented disc embodiment, round ejection disc  400  in position between upstream and downstream conveyor belt assemblies  420 ,  421 , respectively. The ejection disc is mounted to a shaft which is rotatably driven by a gear motor  430 . The gear motor is mounted to a frame member which is pivotably mounted about an axis P, and actuated about that axis by an actuator  440 . The actuator has essentially two positions, the “ejecting position”, and a “retracted” position which is known in FIG.  20 . 
     FIG. 21 is a front end view of a rear flanged plate assembly  460  used in the FIG. 20 configuration. 
     FIG. 22 is a side elevational of a motor  430  having a shaft  431  having a rear flanged plate assembly  460  mounted thereon. 
     FIG. 23 is a pictorial view of a half wheel segment  402  of the FIG. 20 configuration, configured mostly of molded urethane in one embodiment. This half wheel segment  402  includes an embedded metal rectangular rod  404 . 
     FIG. 24 is a pictorial view of a front steel plate of approximately ⅛ inch in thickness. This front plate includes a two large slots  452 , and two opposing small notches  453 . 
     FIG. 25 is a right side elevational view of the first multi-segmented disc configuration, with two half wheel segments  402  installed thereon. No front plate or associated hardware is yet in place. 
     FIG. 26 is a rear elevational view of that shown in FIG. 25, with the motor not shown. 
     FIG. 27 is a front end view of the first multi-segmented disc  400  embodiment, showing the spring  470  and a pipe spacer in place. 
     FIG. 28 is a right side elevational view of that shown in FIG.  27 . 
     FIG. 29 is a front end illustrative view of a second multi-segmented wheel embodiment, shown in round configuration. 
     FIG. 30 is a pictorial view of that shown in FIG. 29, except no tension spring is shown. 
     FIG. 31 is a side illustrative view of a portion of the main disc portion  502  of the FIG. 30 configuration, showing a steel pin such as  510  in detail. 
     FIG. 32 is a top plan view of the second multi-segmented wheel embodiment according to the present invention, illustrating the beveled interconnection between the insert portion  503  and a main disc portion  504 . Also shown is the capturing provided by the front plate  550  and the rear flange plate assembly  560 . Finally shown is a pipe ring  513  which can be placed on the front side of the front plate. 
     FIG. 33 is a front view of a front plate  550 , showing a pair of holes and a key tab. 
     FIG. 34 is a side elevational view of the second multi-segmented disc configuration according to the present invention, showing the main wheel portion  502  and the smaller insert portion  503  in place with a spring and pipe washer likewise in place. 
     FIG. 35 is a rear isolated plan view of a rear flanged plate assembly  560  according to the present invention, which includes a rear plate  561 , and a rear flange  564 . 
     FIGS. 36 and 37 illustrate top plan and side elevational views, respectively of third multi-segmented ejection disc  600  according to the present invention. In this particular embodiment, the multi-segmented disc includes a “flat spot”, although as shown elsewhere in this application such a multi-segment disc could not have a flat section. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now in more detail to the drawings, in which like numerals refer to like parts throughout the several drawings, FIG. 1 shows a top plan view of an automated sorting system embodying the present invention. With reference to FIGS. 1,  2  and  3 , the sorting system  10  preferably includes a cog belt conveyor system  20  comprised of a pair of continuous cog belt conveyors  21  positioned in parallel spaced-apart relation. In a preferred form shown, the cog belt conveyor system  20  forms a closed loop. As shown in FIGS. 1 and 2, the cog belt conveyor system  20  may include a plurality of ejection mechanisms  80  for discharging items, such as parcels  40 , from the surface of the parallel cog belt conveyors  21  onto a variety of output destinations such as receiving chutes  45 , a parallel conveyor (not shown), or a non-parallel conveyor (not shown). 
     The parcels  40  may be loaded onto the cog belt conveyor system  20  manually or by a feed conveyor  53 . A conventional centering roller bed  50  may be used to properly orient the parcels  40  onto the conveying surfaces of the cog belt conveyors  21 , as shown in FIG.  1 . Other sub-assemblies of the sorting system  10  include a self-tensioning gear motor drive system  36  for providing proper tension in the cog belt conveyors  21  of the cog belt conveyor system  20 , as shown in FIG.  6 . The assemblies and sub-assemblies thus far noted and shown will now be described in detail. 
     Referring still to FIGS. 1 and 2, the cog belt conveyor system  20  is comprised of a pair of cog belt conveyors  21  configured in spaced-apart relation for transporting an object such as parcel  40  on the upper surface of the cog belt conveyors  21 . In the preferred form shown, the cog belt conveyors  21  include a smooth outer conveying surface. Cog teeth  22  are disposed along the inner surface of the cog belt conveyors  21  for engaging a cog belt drive mechanism  24 . The drive mechanism  24  preferably includes a drive sprocket  26  configured for engagement with the cog teeth  22  disposed along the inner surface of the cog belt conveyors  21 , as shown in FIG.  2 . An electric motor (not shown) is preferably functionally attached to the drive sprocket  26 . As shown in FIG. 2, the cog belt conveyors  21  are supported at the end opposite the cog belt drive means  24  by an idle sprocket  25 . 
     A feed conveyor  53  is provided for automatically loading objects, such as parcel  40 , onto the cog belt conveyor system  20 . A centering roller bed  50  is interposed between the feed conveyor  53  and the cog belt conveyor system  20 . The centering roller bed  50  is comprised of a plurality of rollers  52  configured in a herringbone configuration. Preferably, the roller bed  50  serves to center and properly orient an object such as a parcel  40  onto the parallel cog belt conveyors  21 , as shown in FIG.  1 . As shown in FIG. 1, a plurality of discharge chutes  45  are provided adjacent to the cog belt conveyors  21  for receiving parcels  40  discharged from the surface of the cog belt conveyors  21 , as will be discussed and detailed below. It should be understood, that a variety of discharge destinations may be utilized, such as bins and separate conveyors (not shown). 
     An alternate configuration for the cog belt conveyor system  20  is shown in FIG.  3 . In the alternate configuration for the cog belt conveyor system  20 , the cog belt conveyors  21  are supported by a pair of idler rollers  35 . As shown in FIG. 3, the cog belt conveyors  21  of this embodiment are disposed about the idler rollers  35  such that the outer conveying surface of the cog belt conveyors  21  include cog teeth for engagement with a self-tensioning gear motor drive system  36 . The inner surface of the cog belt conveyors  21  are smooth for engagement with the idler rollers  35 . 
     The self-tensioning gear motor drive system  36  includes a reversible gear motor  38 . As shown in FIG. 4, the reversible gear motor  38  is attached to a drive shaft  42  on which is disposed a pair of drive sprockets  43  for engaging and driving the pair of parallel cog belt conveyors  21 . As shown in FIG. 3, a pair of snub rollers  44  are utilized to keep the cog belt conveyors  21  in continuous engagement with the drive sprockets  43 . 
     A tensioning mechanism  54  is provided for maintaining proper tension in the cog belt conveyors  21  of this embodiment of the present invention. As shown in FIG. 4, the tensioning mechanism  54  is comprised of a tension spring  55  which is retained by a spring retaining member  52 . At the lower end of the tension spring  55  is a spring compression and release member  56 . The spring compression and release member  56  is actuated by hydraulic cylinder  57  which contains hydraulic fluid  58 . As is well known to those skilled in the art, a suitable pneumatic cylinder may be used in place of the hydraulic cylinder  57 . Tension in the cog belt conveyors  21  may be increased by manually actuating the hydraulic cylinder  57 , or operation of the tensioning mechanism  54  may be directed by a programmable logic controller (not shown). It should be understood, that a variety of tension spring mechanisms may be used in place of the tensioning mechanism  54  for manually or automatically maintaining constant tension in the cog belt conveyors  21 . 
     Referring now to FIGS. 4 and 5, a portable gear motor  60  is provided for powering the sprockets  40  and cog belt conveyors  21  in the event of a failure of the reversible gear motor  38 . As show in FIG. 4, the portable gear motor  60  is mounted on a wheeled table  63  to allow the portable gear motor  60  to be moved into any desired position. As shown in FIG. 4, an emergency drive sprocket  68  is disposed on the end of the drive shaft  42  opposite the reversible gear motor  38 . As shown in FIGS. 4 and 5, the portable gear motor  60  includes a drive sprocket  69  for engagement with the emergency drive sprocket  68 . A power cord  72  is included for providing power to the portable gear motor  60 . 
     Referring now to FIGS. 1,  2 ,  6  and  7 , the sorting system  10  includes a plurality of ejection mechanisms  80  for ejecting an object, such as a parcel  40 , laterally from the upper surface of the cog belt conveyors  21  to an adjacently disposed discharge destination, such as a chute  45 , or other desired discharge destination, such as a bin, or alternate conveyor. The ejection mechanism  80 , shown in FIGS. 1 and 6, is disposed medially of the parallel cog belt conveyors  21 . The ejection mechanism  80  is mounted subjacent to the upper surface of the cog belt conveyors  21 . 
     The ejection mechanism  80  includes a discharge drum  85  and a discharge drum drive motor  87 , as shown in FIGS. 6,  7  and  8 . As shown in FIGS. 6 and 8, the discharge drum  85  is an elongate member defining a generally rectangular transaxial cross-section and having upper and lower surfaces  89   a  and  89   b . The discharge drum  85  has first and second opposing sides  86   a  and  86   b . which are disposed adjacent to the upper and lower surfaces  89   a  and  89   b . The first and second opposing sides  86   a  and  86   b  are generally convex shaped and are separated by the longer cross-sectional diameter of the discharge drum  85 . 
     As shown in FIGS. 6,  7  and  8 , a plurality of flexible ridges  92  are disposed along the surfaces of the convex opposing sides  86   a  and  86   b  of the discharge drum  85 . The flexible ridges  92  may be made from any suitable polymer material such as polyurethane. As will be discussed below, the flexible ridges  92  assist in ejecting an overlying object, such as the parcel  40  from the conveying surface of the cog belt conveyors  21 . 
     A discharge drum drive shaft  88  is configured through the central longitudinal axis of the discharge drum  85 . A discharge drum drive sheave  93  is attached to one end of the discharge drum drive shaft  88 , as shown in FIG.  8 . As shown in FIG. 6, a reversible discharge drum drive motor  87  includes a drive motor sheave  96  for driving a drive belt  90  to impart rotation to the discharge drum  85 . As shown in FIGS. 1,  6  and  7 , the axis of rotation of the discharge drum  85  is defined by the discharge drum shaft  88 . The axis of rotation of the discharge drum  85  lies along the axial center of the path of travel of the cog belt conveyors  21 . As shown in FIGS. 6 and 7, the axis of rotation of the discharge drum  85  remains fixed beneath the conveying surfaces of the cog belt conveyors  21 . 
     In operation, the ejection mechanism  80  is used to discharge an object such as the parcel  40  from the upper surface of the cog belt conveyors  21 , as shown in FIG.  7 . The configuration of the ejection mechanism  80 , as shown in FIG. 6, represents the rest state of the ejection mechanism  80 . When the ejection mechanism is at rest, as illustrated in FIG. 6, the upper surface  89   a  of the discharge drum  85  is in the up position, as shown in FIG.  6 . In this configuration, the upper surface  89   a  lies subjacent to the conveying surfaces of the cog belt conveyors  21 . Accordingly, an object, such as a parcel  40 , may freely travel over the ejection mechanism  80 , if desired. 
     In order to eject the parcel  40  to an adjacent chute  45 , as shown in FIG. 7, the discharge drum drive motor  87  is energized when the parcel  40  moves into a position immediately above the ejection mechanism  80 . If it is desired that the parcel  40  be discharged to a chute  45  located to the right of the ejection mechanism  80 , the discharge drum drive motor is energized so that the discharge drum rotates in a clockwise manner, as shown in FIG.  7 . It should be understood, however, that the parcel  40  may be discharged to the chute  45  located to the left of the ejection mechanism  80  by reversing the polarity on the discharge drum drive motor  87  in a manner well known to those skilled in the art. 
     As shown in FIG. 7, energization of the discharge drum drive motor rotates the discharge drum  85  clockwise or counterclockwise, as desired. As the discharge drum  85  rotates, one of the two convex opposing sides  86   a  rotates through an arcuate path. The arcuate path begins below a plane defined by the upper surface of the cog belt conveyors  21  and rises above that plane through an opening defined by the space between the cog belt conveyors  21  or between the roller arrays, shown in FIG.  9  and discussed below. The arcuate path then terminates below the plane defined by the surface of the cog belt conveyors  21 . 
     Accordingly, one of the convex opposing sides  86   a  contacts the lower surface of the parcel  40 , as shown in FIG. 7, and lifts the parcel  40  up and away from the surface of the cog belt conveyors  21 . The flexible ridges  92  disposed on the surfaces of the convex opposing sides provide contact surfaces to assist in movement of the parcel  40  by increasing friction between the convex opposing side and the parcel  40 . 
     As the discharge drum  85  continues to rotate, the parcel  40  is tilted away from the upper surfaces of the cog belt conveyors  21  and onto an idler roller  46  interposed between the cog belt conveyors  21  and the chutes  45 , as shown in FIG.  7 . Finally, as the discharge drum  85  completes a full 180 degrees of rotation, the parcel  40  is translated onto the chute  45  and off the conveying surfaces of the cog belt conveyors  21 . Accordingly, rotation of the discharge drum  85 , as described, lifts, tilts, and translates the parcel  40  from the conveying surfaces of the cog belt conveyors  21 , and such rotation returns the discharge drum to a rest position, as shown in FIG.  6 . 
     As shown in FIG. 9, an alternate embodiment of the present invention provides an ejection mechanism  80  disposed beneath the conveying surface of a roller bed conveyor  100 . The roller bed conveyor  100  defines a pair of spaced-apart arrays of rollers. It should be understood that the rollers may be powered or non-powered idler rollers. The rollers define axes of rotation which are transverse to the axis of rotation of the discharge drum  85 . The roller bed conveyor  100  and ejection mechanism  80  may be positioned adjacent to desired discharge destinations and interposed between two belt conveyors  105  and  110 , or the ejection mechanism and roller bed  100  configuration shown in FIG. 9 may form part of a continuous roller bed conveyor arrangement (not shown). 
     A tapered discharge drum  120  is shown in FIGS. 10 and 11. As shown in FIG. 11, a transaxial cross-sectional view of the tapered discharge drum  120  shows a generally rectangular shaped discharge drum  120 , defining convex opposing sides  123   a  and  123   b  separated by the longer diameter of the drum. As shown in FIG. 10, the convex opposing sides  123   a  and  123   b  of the tapered discharge drum  120  define flexible ridges  126  and are tapered longitudinally, narrowing toward the end having the drive sheave  96  for engagement with the drum drive motor  87  via a drive belt  90 , as shown in FIG.  6 . As shown in FIG. 1, the tapered discharge drum also tapers longitudinally narrowing in the direction opposite to the of travel of the cog belt conveyors  21 . Accordingly, the second end  125  of the tapered discharge drum  120  is wider than the first end  124 . 
     Discharge of a parcel  40  using the non-tapered discharge drum  85 , as described above, tends to rotate the parcel  40  as the parcel  40  is being discharged. Rotation of the parcel is a result of the forward movement of the parcel  40  along the cog belt conveyors  21  in concert with the lateral displacement of the parcel  40  by the discharge drum  85 . More specifically, as the tapered discharge drum  85  lifts the parcel  40  off one of the cog belt conveyors  21 , the other cog belt conveyor continues to urge the parcel in a forward direction, resulting in an unbalanced force that causes rotation of the parcel  40 . If desired, the tapered discharge drum  120  may be utilized to counteract rotation of the parcel  40  as it is discharged from the cog belt conveyors  21 , as shown in FIG.  7 . That is, as a parcel  40  is discharged from the surface of the cog belt conveyors  21  by the tapered discharge drum, the parcel  40  is contacted first by the wider second end  125  of the tapered discharge drum  120  which urges the parcel  40  in a direction counter to the direction of rotation caused by the cog belt conveyor  21 . Accordingly, the parcel  40  is discharged from the conveying surfaces of the cog belt conveyors  21  without undesired rotation. 
     It should be understood the ejection mechanism need not be a drum and that the side of the ejection mechanism that engages the parcels  40  need not be a continuous surface. 
     The automated sorting system  10  is operated under the control of a digital controller, which may be a programmable logic controller (PLC) or a general purpose microprocessor which is found in a personal computer. Methods for programming such controllers to operate a sorting system of the type disclosed herein are conventional and known to those skilled in the art. 
     In operation, the number of and location of ejection mechanisms  80  and an identification code for each ejection mechanism  80  are input into the controller memory when movement of the sorting system  10  begins. Parcels  40  are induced sequentially onto the roller bed  50  from the feed conveyor  53 , as shown in FIGS. 1 and 2. As shown in FIG. 1, a destination code for each parcel  40  is entered into the controller memory using an optical reader  51 , a keypad (not shown), or a voice recognition input device (not shown) before the parcel  40  is directed onto the cog belt conveyor system  20 . A suitable optical reader system  51  for imaging the destination code from a label affixed to the parcel  40  is shown in U.S. Pat. Nos. 5,291,564; 5,308,960; 5,327,171; and 5,430,282 which are incorporated herein by reference. The roller bed  50 , with herringbone configuration rollers  52 , centers the parcel  40  so that the parcel  40  squarely aligns about the longitudinal axis of the cog belt conveyor system  20  and on the surfaces of the cog belt conveyors  21 , as shown in FIG.  1 . 
     When the parcel  40  reaches a desired output destination, such as a chute  45  in a position overlying a desired ejection mechanism  80 , the PLC energizes the discharge drum drive motor  87  to actuate the ejection mechanism  80 . Accordingly, the discharge drum  85  rotates in the direction of the chute  45 . As the discharge drum  85  rotates about the discharge drum drive shaft  88 , one of the first and second convex shaped opposing sides arcuately translates between the pair of continuous cog belt conveyors  21  and above the upper surface of the continuous cog belt conveyors  21 . The discharge drum  85  rotates in the direction of the chute  45 , and the parcel  40  is lifted from the surfaces of the cog belt conveyors  21 , as shown in FIG.  7 . As the discharge drum  85  continues to rotate in the direction of the chute  45 , the parcel  40  is tilted on to the idler roller  46 , as shown in FIG.  7 . Finally, as the discharge drum completes its rotation, as described in detail above, the parcel  40  is discharged onto the chute  45 , as shown in FIG.  7 . After the parcel  40  is discharged to the chute  45 , the discharge drum  85  stops in a rest position, as shown in FIG. 6, and stands ready to discharge a subsequent parcel  40 . If it is desired that package rotation be counteracted as the parcel is discharged to the chute  45 , a tapered discharge drum  120  may be utilized instead of the discharge drum  85 , as described above. 
     Use of the ejection mechanism  80 , as described, allows the parcel  40  to be discharged from the surfaces of the cog belt conveyors  21  independent of the speed of the parcel  40  moving along the cog belt conveyors  21 . Additionally, interaction of the flexible ridges  92  disposed along the surfaces of the convex opposing sides of the discharge drum  85  or the tapered discharge drum  120  reduces noise created by the impact of the discharge drum  85  with the overlying parcel  40 . Advantageously, failure of an individual ejection mechanism  80 , or the cessation of use of an individual ejection mechanism  80  for the maintenance purposes does not create downtime for the cog belt conveyor system  20 . In the event of the cessation of use of an individual ejection mechanism  80 , the PLC may direct parcels to be discharged to alternate discharge destinations and bypass the stopped ejection mechanism  80 . Furthermore, the discharge drums may be quickly and easily replaced. Accordingly, downtime of the cog belt conveyor system  20  is reduced. 
     Reference is now made to FIGS. 12-37 in discussing the general concept of providing a relatively narrow package-ejecting disc, which can be used within a gap defined by two conveyor belts or other conveying item. As will be discussed in detail further below, the disc can be substantially round in shape, or can include a “flat spot”, and can also either be of substantially unitary construction or multi-segmented. 
     Reference is first made to FIGS. 12 and 13 in order to explain the general narrow package-ejecting disc concept. FIG. 12 is a top plan view of a portion of a conveyor system according to the present invention, illustrating an ejection disc  100  located between upstream and downstream conveyor belt assemblies  120 ,  121 , respectively, and rotatably driven about an axis  105 . FIG. 13 is an “upstream” sectional view taken generally along the conveying axis, showing an ejection disc  100  ejecting a package to the viewer&#39;s right. 
     As shown in FIGS. 12 and 13, the parcel  112  is moved along a generally straight conveyor axis  113 , being first positioned atop an upstream conveyor belt assembly  120 , and is conveyed towards and onto a second downstream conveyor belt assembly  121 , unless it is ejected. An ejection disc  100  is rotatably located within a relatively narrow transverse “slot” or “gap”  110  intermediate the two belts of the two assemblies  120 ,  121  to provide the ejection. It should be understood that the gap is substantially narrow in that it is shorter along the conveying dimension that in its transverse, perpendicular dimension. 
     A side chute  112  is positioned at approximately 90 degrees relative to the conveying axis  113 , and received ejected packages. 
     In FIG. 12, a parcel  12  is shown in approaching the ejection disc  100 . If the ejection disc  100  ejects the parcel  112 , the parcel will be urged into the area of a side chute  114 . If the ejection disc  100  does not eject the parcel  112  as shown in FIG. 13, the parcel is passed from the upstream conveyor belt assembly  120  to the downstream conveyor belt assembly  121 . As may be seen, the two conveyor belts within the two conveyor belt assemblies include substantially planar upper conveying surfaces, which lie substantially along the same horizontal plane. 
     As shown in FIG.  13  and as discussed in detail elsewhere, the disc  100  can be round or may include a truncated section defined in part by a flat spot  102 . In either case, the peripheral edge  101  of the ejection disc  100  is brought into contact with the underside of the package as discussed later, such that the parcel is discharge to the viewer&#39;s right as viewing FIG.  13 . 
     The gap  110  can be thought of as having a thickness defined by the closest distance shown between the two conveyor belts, and can be thought to extend above, below, and to intersect the conveying axis. 
     FIGS. 14-17 illustrate the use of a ejection disc  200  with a flat spot defining a truncated section. Under this concept, a “truncated”, disc is used which fits within the transverse slot defined by the end of one belt conveyor and the beginning of a second, downstream belt conveyor. This disc includes a truncated section which operates much the same way as the “truncated” drum described earlier. The truncated disc is rotatably mounted on a fixed axis, and selective rotation causes the disc to engage and eject a package, when rotation is suitably timed. 
     Reference is now made to FIG. 14, which is a side elevational view of a conveyor configuration according to the invention. A package  212  can be moved from an upstream conveyor belt assembly  220  to a downstream conveyor belt assembly  221 , unless ejected by a ejection disc  200  as described below. As may be seen, the two conveyor belts within the two conveyor belt assemblies  220 ,  221 , include substantially planar upper conveying surfaces, which lie substantially along the same horizontal plane. 
     As in the configuration of FIGS. 12 and 13, the ejection disc  200  is positioned within and rotates within a transverse gap  210  intermediate the two belts assemblies  220 ,  221 . 
     As shown in FIG. 15, the ejection disc  200  includes a flat section  202 . When the disc  200  is in its unengaging or “neutral” position as shown in FIG. 14, the flat section  202  allows passage of the package. Otherwise, the disc  200  is at least partially in the conveyor path. 
     FIGS. 16 and 17 illustrate what happens when the ejection disc is rotated 180 degrees about its rotational axis  205  from that shown in FIGS. 14 and 15. As may be seen, when the ejection disc  200  is actuated through rotation, its curved portion (having a gripping surface) rises above the conveyor surface, causing the package to be lifted. As the disc is likewise rotating, this engagement causes the package to encounter a force substantially 90 degrees in relation to the conveying axis of the package moving from upper conveyor belt assembly  220  to upper conveyor belt assembly  221 . 
     As noted above, the ejection disc  200  is rotatably mounted relative to the conveying path of the packages in contacts. This rotational axis, in the configuration shown in FIGS. 14-17, is substantially stationary, horizontal, and parallel to the conveying axis of the packages above, although slight variations may be provided as needed. The conveying axis lies substantially along a drive shaft  231  which is rotatably driven by an indexing servo motor  230 . This indexing servo motor is configured to be selectively activated to rotate the disc  200  in either rotational direction, allowing ejection to be provided to either side of the conveying axis. 
     In one preferred embodiment shown in FIGS. 15 and 17, the outer edge of the ejection disc includes a plurality of teeth  203 , which are in one preferred embodiment comprised of rubber. 
     It should also be understood that alternative configurations, which include chain or other drives allowing for the remote location of an indexing motor are contemplated under the spirit and scope of the present invention. 
     Reference is now made to FIGS. 18 and 19, which illustrate the use of a round ejection disc  300  which is indexed upwardly above the conveying surface within the gap  310  between two conveyors by use of a pivoting action. 
     This configuration includes a round ejection disc  300  mounted to a shaft which is rotatably driven by a motor  330 . The motor  330 , which can be continuously running if desired, is mounted to a pivoting support member  333  which is pivotably mounted relative to a stationary conveyor frame member (not shown). This pivoting support member  333  is pivotably mounted about a pivoting axis which is substantially horizontal as well as transverse to and below the package conveying axis path. 
     A linear actuator  340  is provided which actuates the frame member  333 , the motor  330 , and the disc  300  from a retracted (non ejecting) position (see FIG. 18) to an extended (ejecting) position (see FIG.  19 ). 
     As may be seen, when the actuator  340  (which may be an air or other extendable cylinder) urges the disc  300  upwardly, the rotational axis  305  goes from being substantially horizontal to inclined. Hydraulic, pneumatic, or other suitable actuation means known in the art can be used. 
     The narrow, substantially circular, ejection disc  300  fits within the transverse “slot”  310  defined by the end of an upstream belt conveyor assembly  320  and a downstream and the beginning of a second, downstream belt conveyor assembly  321 . The circular disc  300  is rotatably mounted on a movable rotational axis  305 . While in its “neutral” position as shown in FIG. 22, the disc  300  does not contact the packages as they pass from the upstream to the downstream conveyor. However, when actuated, the disc  300 , being moved upwardly to its “engaging” position shown in FIG. 21, contacts the package on its circular edge. Rotation of the disc causes the package to be discharged sidewardly. 
     The above motor  330  can be reversible to allow for discharge to either side of the conveyor. If desired, the motor can be left continuously running allowing the actuator to determine when ejection occurs. The motor  330 , as with all the motors described in this application can be selected as known in the art. 
     This concept, shown generally in FIGS. 20-37, generally relates to the use of a “quick change” feature which allows the narrow discs be quickly removed and replaced with little or no tools and with minimal disturbance to adjacent machinery. This is very important to those operating and maintaining said machinery, in that downtime due to repairs are desired to be at a minimum. 
     FIGS. 20-28 show a first multi-segment embodiment, with a multi-segmented ejection disc  400 . 
     FIGS. 29-35 show a second multi-segment embodiment, including a multi-segmented ejection disc  500 . 
     FIGS. 36-37 show a third multi-segment embodiment, including a multi-segmented ejection disc  600 . 
     FIGS. 20-28 show a first multi-segmented disc embodiment, including a multi-segmented ejection disc  400  which generally includes a pair of half wheel segments  402 , which are captured between a front plate  450  and a rear flanged plate assembly  460  and maintained in place by use of a tension spring  470 , to form a substantially circular ejection disc  400 , although a wheel with a flat spot is readily contemplated. 
     FIG. 20 illustrates the multi-segmented round ejection disc  400  in position within a gap  410  between upstream and downstream conveyor belt assemblies  420 ,  421 , respectively. The ejection disc  400  is mounted to a shaft  431  which is rotatably driven by a gear motor  430 . The gear motor  430  is mounted to a pivotable support member  433  and actuated about pivoting axis by an actuator  440 . The pivotable support member  433  is pivotably mounted relative to an unshown stationary frame member about a pivoting axis which is substantially horizontal as well as transverse to and below the package conveying axis path. 
     The actuator  440  has essentially two positions, an “ejecting position”, and a “retracted” position, and is configured to operate such that the multi-segmented ejection disc  400  can be raised generally upwardly and downwardly within the gap  410  much as the disc  300  moved as shown in FIGS. 18 and 19. 
     For discussion purposes, the configuration will be assumed to have a “front” and a “back”, although such terms are not to be construed as being limiting. The “front” of the ejection disc  400  is the part oriented to the viewer&#39;s left as viewing FIG.  20 . 
     As shown in FIG. 22, attached to the shaft  431  of the motor  430  is a rear flanged plate assembly  460 , which includes a rear plate  461 , a rear flange  464 , and a set screw  465 . As shown in FIG. 21, the rear plate  461  includes two opposing large slots  462 , and also includes two small notches  463 . The large slots  462  are oriented approximately 90 degrees from the opposing smaller notches  463 . The rear flange  464  is substantially rigidly attached to the rear plate  461 , by welding or other means known in the art. The set screw  465  allows for attachment of the rear flange  464  to the shaft  431 , as known in the art. 
     Reference is now made to FIG. 23, which is a pictorial isolated view of a half wheel member  402 , two of which are used for each disc  400 . Each of the half wheel members  402  includes a corresponding embedded rod  404 . At the front end of each embedded rod is defined in embedded rod slot  405  or other suitable engaging means, and at the opposite, rear, end is an embedded rod hook  406  or other suitable engaging means. As described elsewhere in this application, the embedded rod slots  405  are each configured to accept one end of a tension spring  470 , and the embedded rod hooks  406  are configured to pass through slots  463  of the rear flange plate  461 , and engage the rear side of the rear flange plate  461 . 
     Each of the half wheel members  402  is configured mostly of molded urethane in one preferred embodiment with the exception of the metal embedded rod  404 . In one preferred embodiment, the rods  404  have a rectangular transverse cross section. 
     Reference is now made to FIG. 24, which is an illustration of a front steel plate  450  of approximately ⅛ inch in thickness. This front plate includes two opposing large slots  452 , and two opposing small notches  453 . The opposing large slots  452  and two opposing small notches  453  of the steel front plate  450  are similar in configuration to those provided in the rear plate  461  of the rear flange plate assembly  460 . 
     As shown in FIGS. 27 and 28, a tension spring  470  and a “pipe”  471  are also included. A key  466  is used to provide a keyed connection as described later. 
     As shown in FIG. 22, the rear flanged plate assembly  460  is mounted to the shaft  431  of the gear motor  430 , by passing the collar-shaped rear flange  464  over the substantially circular outline of the shaft  431 . When the rear flange  464  is positioned at its desired location, a set screw  465  is installed in order to fix the rear flange  464  to the shaft  431  of the gear motor  430 . A key as known in the art provided a keyed engagement between the rear flanged plate assembly  460  and the shaft  431 . 
     After the rear flanged plate assembly  460  is mounted to the shaft  431 , the two half wheel members  402  are situated as shown in FIG. 25, and held in place by the use of a front plate  450  as shown in FIG.  27 . 
     When the two half wheel members  402  are in place as shown in FIG. 26, it may be seen that the half knob segments  403  of the half wheel members  402 , combine to provide substantially elliptically-shaped knobs, shown well in FIG.  26 . These knobs are partially contained by the large cut outs of the front plate  450 , which serves to capture the half wheel members  402  between the front plate  450  and the rear plate  461  of the rear flange plate assembly  460 . 
     When installed, the embedded rods  404  of the half wheel members are configured such that their hooks  406  are engaged with the “rear” side of the rear flange plate  461 , as shown in FIGS. 25 and 26. 
     After positioned as shown in FIG. 25, the front plate  450  is positioned into place as shown in FIG.  27 . As may be understood, the front plate is placed relative to the half wheels and their embedded rods  404 , such that the front ends of the embedded rods pass through the small notches  453  of the front plate  450 . 
     After the front plate  450  is in place, a tension spring  470  is stretched such that its two ends engage respective slots  405  in the front ends of the embedded rods  404 , such that the spring ends are engaged with the respective embedded rod slots  405 . However, before the spring  470  is situated into place, a pipe spacer  471  is placed in engagement with the front plate  450 . The spring is then positioned into place, such that the spring is engaged at its ends with the embedded rods, and the medial portion of the spring  470  biases radially against the end of the substantially short pipe spacer  471 , which biases inwardly onto the front plate  450 . 
     As shown in FIG. 27, a curved portion is provided in the pipe spacer to accommodate the round nature of the spring, and to discourage removal of the pipe spacer. 
     The pipe spacer  471 , in one preferred embodiment, fits about the end of the shaft  431  of the gear motor  430 . This engagement, combined with the biasing of the spring, tends to maintain the pipe spacer in place. 
     A key  466  as known in the art to provide suitable engagement between the rear flange  464  and the shaft  431 , to discourage rotation therebetween. 
     Operation of the configuration shown in FIGS. 20-28 is similar to that discussed in reference to FIGS. 18 and 19. A motor  430  is used which drives the ejection disc  400 , such that when the motor  430  and rotating disc  400  is pivoted upwardly by an actuator  440 , the ejection disc engages and discharges packages passing gap  410 . 
     Although this configuration includes the use of an pivoting configuration, if a flat spot is provided in one or both of the half wheels  402 , as may be understood, no pivoting is required; the motion will be as described earlier with respect to FIGS. 14-17. 
     In order to change a wheel configuration, a user will disengage the spring  470  from its location, remove the pipe spacer  471 , remove the front plate  450 , and remove and replace as needed either or both of the half wheels  402 . The front plate  450  is then positioned as shown in FIGS. 27 and 20, and the pipe spacer  471  and spring  470  are situated into place as shown in FIGS. 20,  27 , and  28 . 
     As noted above, although the multi-segmented ejection disc  400  is shown as having a circular gripping perimeter edge, a truncated portion could also be provided by providing such a truncation in at least one of the half wheel segments  402 . 
     FIGS. 29-35 show a second multi-segment disc embodiment  500 , including a main disc portion  502 , an insert portion  503 , and a spring  512 . 
     The configuration of FIGS. 29-35 includes a multi-segmented urethane wheel. The wheel portion which contacts the package takes the form of two urethane segments, a main disc portion  502  and an insert portion  503 . The main disc portion  502  includes a large slot therein, and the smaller insert portion is configured to slide within the slot of the main disc portion. As shown in FIG. 32, this insert can include a beveled configuration, which tends to provide engagement between it and the main wheel portion. These urethane members  502 ,  503 , are drawn together by the use of a tension spring  512 , which has each of its ends engaging one of the headed portions of embedded steel pins. 
     As shown in FIGS. 29 and 30, the main disc portion  502  includes an embedded pin  510 . The embedded pin includes a rear hook  520 , and includes a front “headed” portion which defines an annular slot  521 . 
     The main disc portion  502  also includes an insert-receiving slot which at its end includes a substantially arcuate portion having a keyway slot therein. The keyway slot is configured to accept a key as described elsewhere. 
     The insert portion  503  includes an insert portion pin  511  similar in configuration to pin  510  of the main portion  502 . The insert portion  503  includes an arcuate end, which is configured to conform substantially to a peripheral portion of a shaft as described elsewhere. 
     Referring now also to FIGS. 32 and 33, the rear flanged plate assembly  560  also includes a rear plate  561 , a rear flange  564  rigidly attached thereto, and is keyed as known in the art to engage the shaft. 
     The front plate  550  is configured to include a key tab  551  to engage a keyway in the drive shaft  531 , and includes a pair of through holes  552  to allow passage of the through pins  510 ,  511 . A pipe ring  570  is also used as described below. 
     The outer surface of both portions  502 ,  503  is provided with gripping teeth or another suitable gripping surface such as known in the art. 
     As shown in FIG. 32, the rear flanged plate assembly  560  fits onto a shaft  531  of a motor  530 . 
     The two urethane portions  502 ,  503 , are configured to fit together in their configuration shown in FIG. 32, such that the front plate and the rear plate  561  of the rear plate assembly  560  tend to capture the urethane portions  502 ,  503 , along the length of the shaft  531  of the motor  530 . The urethane portions  502 ,  503 , are drawn together by the use of a spring  512 , which has each of its ends engaging one of the headed portions of the embedded steel pins and captures the pipe ring  570  as shown. 
     A keyway is provided to allow keyed engagement between the shaft  531  of the gear motor  530  and the front plate  550 , the main urethane wheel member  502 , and the rear flange plate assembly  560 . 
     To replace one or both of the urethane portions  502 ,  503 , the spring  512  is first removed, followed by removal of the front plate  550 . The urethane portions  502 ,  503 , can then be separated by sliding the smaller member  503 , out of the main slot of the larger member  502 . Replacement of either or both of the urethane members can then be effected. After the urethane members are in place, the front plate  550  is then replaced, followed by the spring  512 . If desired, a pipe ring  570 , as shown in FIG. 32, can be used to fit underneath the spring  512  as shown in FIG.  34 . 
     Operation of the disc  500 , being round, is similar to the disc  400 , although a flat spot may be alternately provided to be used with the pivoting configuration described in reference to FIGS. 18 and 19. 
     FIGS. 36 and 37 illustrate top plan and side elevational views, respectively of third multi-segmented ejection disc  600  according to the present invention, including a main disc portion  602  and an insert portion  603  slidably insertable into the main portion in a manner similar to that described previously, with respect to, for example, FIG.  30 . However, in this configuration, a tension spring  612  is used which engages at its ends to two respective pins each of which are installed in the main disc portion on opposing sides of the main portion&#39;s insert-receiving slot. The medial portion of the spring  612  is stretched around a pin member extending through the insert portion  603  and having upwardly (as shown in the drawings) directed hooks which are biased downwardly (as shown in the drawings), such that the spring force tends to cause the plastic insert to remain seated within its position in the main wheel portion. 
     This configuration may be used with a separate means (not shown) to attach the combination of the two elements  602 ,  603  to a motor shaft  620 , or may be modified to operate in conjunction with other mounting elements such as a flanged rear disc assembly and front disc assembly, motor, etc., to be supported and driven thereby in manners similar to those previously discussed. 
     In this particular embodiment  600 , the multi-segmented disc  600  includes a “flat spot”, although as shown elsewhere in this application such a multi-segment disc could not have a flat section. 
     The thickness of the multi-segmented disc  600  as shown in FIG. 36, as well as the other discs may be within the range of ½ inch to 3 inches, and can be approximately 12 inches in peripheral diameter although other configurations are contemplated without departing from the spirit and scope of the present invention. The peripheral edge of the disc  600  intended to engage packages may be provided with engaging teeth or other suitable frictional engaging means known in the art. 
     Therefore it may be seen that the invention provides an improved conveying and discharge apparatus which provides numerous improvements over the previously-described prior art, not the least of which includes a simple yet effective discharge device which can be easily replaced with little downtime. 
     While this invention has been described in specific detail with reference to the disclosed embodiments, it will be understood that many variations and modifications may be effected within the spirit and scope of the invention as described in the appended claims.