Abstract:
An improved jogger includes a sidewall with a guide groove, a chain defining a closed path including a sloped loading end and a straight transport section, the sloped loading end being angled toward the transport section in the direction of the travel of the chain at least two sprockets, the sprockets defining the slope of the sloped loading end of the closed path, a plurality of fingers coupled to the chain at spaced apart intervals, the fingers receiving flat articles therebetween at the sloped loading end and conveying the articles along the horizontal transport section and a plurality of guides coupled to the fingers, the guides engaging the guide groove and orienting fingers in a position perpendicular to the horizontal transport section as the fingers are carried into the sloped loading end.

Description:
TECHNICAL FIELD  
         [0001]    The present invention relates to an apparatus, system and method of feeding flat articles to a sorter, and in particular, to an improved jogger apparatus for use in feeding a mail processing device such as a mail sorter.  
         BACKGROUND OF THE INVENTION  
         [0002]    Modern postal services, for example, the U.S. Postal Service, handle massive volumes of mail pieces on a daily basis. Machines for receiving and sorting these massive volumes of letter mail are known. Typically, such machines are adapted to receive large volumes of flat articles and sort the articles into a plurality of pockets or bins based upon selected criteria. In the case of letter mail, the criteria associated with the destination of the individual mail pieces may be an indicium such as a Zip+4 destination code. Typically, such sorting machines have a feeding station, sensing and detecting equipment for determining the appropriate output compartment or pocket for the article to be sorted and diverting gates or other mechanisms for selectively diverting articles to selected ones of an array of output compartments or pockets for the sorted articles. An example of an advanced sorting machine is the DBSC sorting device, available from Siemens ElectroCom, L.P., Arlington, Tex.  
           [0003]    Devices for singulating and feeding mail pieces to a sorting machine are known. One such apparatus is disclosed in U.S. Pat. No. 5,947,468, the disclosure of which is incorporated herein by reference for all purposes. Typically, such devices for singulating and feeding mail pieces include a jogger type conveyor which functions to advance mail pieces to a take off device that removes the mail pieces on a one-by-one basis so as to convert a stack of mail pieces to a singulated stream suitable for further processing. The jogger also severs to impart a jostling or bouncing motion to the stack as it is advanced in order to facilitate edging, or alignment of one set of edges of the mail pieces. The jostling or bouncing motion tends to separate the mail pieces and cause mail pieces pinched between adjacent pieces in an elevated position to move downwardly so as to align the bottom edge of such pieces with the remainder of the stack. Such prior art jogging devices comprise a series of chain driven fingers that travel though an oval path as the chain is driven around a pair of sprockets. The fingers engage a stack of mail, moving the mail as it is subjected to a jostling or bouncing motion. However, the fingers of such prior art joggers sweep through an arc as the chain passes over the sprocket adjacent to the loading end of the jogger. This results in an undesirable compression of mail between the fingers that hinders the jogging process. The improved jogger of the invention alleviates this shortcoming.  
         SUMMARY OF THE INVENTION  
         [0004]    An improved jogger type conveyor includes a flexible carrier defining a closed path including a substantially straight transport segment along which flat articles are conveyed, a sloped loading end where flat articles are loaded on the conveyor and a discharge end where articles are discharged from the conveyor. The closed path defines a first vertical plane passing through the transport segment, sloped loading end and discharge end of the path. A plurality of fingers are coupled to and extended from the flexible carrier for receiving flat articles at the sloped loading end where the fingers move substantially perpendicularly through a second horizontal plane substantially perpendicular to the first plane and parallel to the transport segment. The flat articles are positioned on edge in a gap defined by adjacent fingers as the articles are loaded onto the conveyor. The jogger includes first guide means coupled to the carrier and second stationary guide means that cooperate such that the gap between the fingers does not decrease in size as the flat articles are loaded and conveyed from the loading end to the discharge end of the conveyor. Causing the gap not to increase results in flat articles positioned on edge in the gaps not being subjected to compression resulting from a decrease in the gap between the fingers.  
           [0005]    In one aspect, the jogger includes plurality of rotatable guides around which the flexible carrier extends. In this regard, the rotatable carrier guides may be sprockets or pulleys arranged in a trapezoidal pattern. One suitable flexible carrier comprises a chain passing around a plurality of sprockets arranged in a trapezoidal pattern and wherein at least one of the sprockets is a drive sprocket.  
           [0006]    In another aspect, the jogger conveyor comprises a return segment and a plurality of brackets coupling the fingers to the flexible conveyor. The brackets include a groove engaging projection for engaging a guide groove adjacent to the path to pivot the bracket as the bracket moves from the return segment to the sloped segment causing the fingers to assume a substantially perpendicular orientation with respect to the second plane. In this aspect, the jogger includes at least one side plate positioned parallel to the vertical first plane with a guide groove formed in the side plate, the groove engaging projection of brackets coupled to the flexible carrier moving through the guide groove and causing a finger coupled to the bracket to pivot to a vertical position as the bracket is carried from the return segment to the sloped segment of the path.  
           [0007]    In another aspect, the jogger includes at least one rotating shaft extending parallel to the transport segment of the path, the shaft imparting a bouncing motion to flat articles carried between the fingers as the flat articles are conveyed through the transport segment. The bouncing motion tends to loosen a stack of flat articles compressed together and align the bottom edges of the flat articles for further processing of the stack. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]    These and other aspects of the invention will hereafter be described with reference to the accompanying drawings, wherein like numerals denote like elements, and:  
         [0009]    [0009]FIG. 1 is a side view of a prior art jogger;  
         [0010]    [0010]FIG. 2 is a perspective view of a mail feeder including a jogger according to the invention;  
         [0011]    [0011]FIG. 3 is partial side view of a jogger in accordance with the invention;  
         [0012]    [0012]FIG. 4 is a partial perspective of the jogger of FIG. 3;  
         [0013]    [0013]FIG. 5 is a partial top view of the jogger of FIG. 3;  
         [0014]    [0014]FIG. 6 is partial perspective view of the jogger of FIG. 3 with elements omitted for the purpose of illustration;  
         [0015]    [0015]FIG. 7 is a perspective view of a finger assembly of the jogger of FIG. 3; and  
         [0016]    [0016]FIG. 8 is a partial top view of the loading end of the jogger of FIG. 3. 
     
    
     DETAILED DESCRIPTION  
       [0017]    While the invention is described below with reference to a preferred embodiment, the description is not intended to be construed in a limiting sense. Various rearrangements of parts, modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to the description.  
         [0018]    [0018]FIG. 1 shows a prior art jogger  10  including a plurality of fingers  12  secured to a drive chain  14  with brackets  16 . In operation, chain  14  is driven around sprockets  22  and  24  with a conventional drive, engaging a stack of mail (not shown) at the loading end  28  of the conveyor. As shown, the tips  18  of fingers  12  travel through path  20  as chain  14  passes around sprockets  22  and  24 , including an arcuate path segment  26  at the loading end  28  of jogger  10  where mail pieces are loaded between the fingers. As chain  14  advances, the tip  18  of each finger  12  slides up and into the stack of mail as the tip travels through path segment  26 . Simultaneously, each finger  12  moves from an angled orientation at the beginning of segment  26  to a substantially vertical orientation at the end of segment  26 . Finger  12   a  is illustrated in the position where it begins to engage a stack of mail at loading end  28  of jogger  10 . Finger  12   b  is illustrated in the vertical position, having traveled through path segment  26 .  
         [0019]    As illustrated, a gap g exists between the tips  18  of fingers  12   a  and  12   b  when the fingers are positioned on either end of segment  26 . However, as the fingers pass through and beyond segment  26  into the straight upper portion  32  of path  20 , the distance between the tips  18  of the fingers narrows significantly, to a gap g′. As will be appreciated, mail pieces loaded between fingers  12   a  and  12   b  in arcuate segment  26  will thus be squeezed or compressed between the fingers as the fingers travel from arcuate segment  26  into the straight upper portion of path  20  where the fingers are vertically oriented. Compression of the mail pieces in this manner hinders the jogging and edging process. Additionally, because fingers  12  are oriented at an angle at the beginning of segment  26  as the fingers slide into the stack of mail pieces being loaded onto jogger  10 , the fingers  12  also have a tendency to lift the mail pieces out of the stack. This in turn can cause mail pieces to be caught in an elevated position as the mail pieces are compressed or fall from the machine.  
         [0020]    Turning now to FIG. 2, a jogger  40  according to the invention is part of a mail feeding apparatus  34  which includes a staging conveyor  36 , jogger  40  and a singulating feeder  38 . In operation, a stack of mail pieces is loaded on edge onto staging conveyor  36  which conveys the stack onto jogger  40  which in turn transports the stack to singulating feeder  38 . As the jogger conveys the stack of mail pieces, it imparts a bouncing or jostling motion to the stack to edge and align the bottom edges of mail pieces in the stack and separate mail pieces that may be stuck together. Jogger  40  transfers the edged stack of mail pieces to the singulating feeder  38  which singulates and feeds the stack on a piece-by-piece basis to a mail sorting machine for further processing.  
         [0021]    Referring now to FIGS.  3 - 8  a jogger  40  according to the invention includes a pair of flexible carriers such as chains  42  (one shown), each passing around and over a plurality of sprockets  44 - 50  arranged in a trapezoidal pattern. Chains  42  define a continuous closed path  52  as the chains pass around upper sprockets  44 ,  46  and lower sprockets  48 ,  50  carrying a plurality of fingers  12  through the path. Path  52  includes a sloped loading end  54  where mail pieces are loaded onto the jogger, a straight transport section  56  where the mail pieces are edged, a sloped unloading end  58  and a return section  60 . Path  52  defines a vertical plane A-A′ passing through sloped loading end  54 , straight transport section  56 , sloped unloading end  58  and return section  60 . A motor  66  drives least one of sprockets  44 - 50  directly or with a known conventional chain or belt drive in the direction indicated with arrow  62 .  
         [0022]    A series of finger brackets  70  are connected to chains  42  with link pins  72  at spaced apart intervals along the chains for carrying one or more fingers  74  that engage a stack  80  of mail pieces  64  positioned on edge as the stack is loaded onto jogger  40  at loading end  54  with a staging conveyor  36 . Fingers  74  pass through a horizontal plane B-B′ as the fingers are transported through sloped loading section  54 . Plane B-B′ is perpendicular to plane A-A′, and as set forth in detail below, fingers  74  are positioned in a substantially vertical orientation as the fingers pass through plane B-B′. In one embodiment, each holder  70  is integrally formed with a plurality of fingers  74  and brackets  70  spaced at intervals of approximately 3 inches along the length of chains  42 . In a preferred embodiment, illustrated in FIG. 7, each bracket  70  is molded from a suitable plastic with three laterally spaced apart fingers  74  extending from the bracket. As shown, each bracket  70  is provided with guide legs  76  for receiving roller guide pins  78  in holes  82 . Guide pins  78  engage guide grooves  84  in side plates  86  of jogger  40  and serve to orient brackets  70  and fingers  74  as the holders are carried by chains  42  around path  52 .  
         [0023]    In operation, stack  80  of mail pieces  64  is pushed or fed from staging conveyor  36  onto the loading or receiving end  58  of jogger  40 . In the embodiment shown in FIGS. 2 and 3, in order to allow jogger  40  to engage and smoothly separate stack  80  into increments corresponding to the distance between fingers  74 , a slotted bridge plate  90  (FIG. 8) is positioned between staging conveyor  36  and jogger  40 . Slotted bridge plate  90  includes a plurality of first slots  92 , plate extensions  94  that are separated by slots  92  and a second slot  96  in one or more of extensions  94 . As the stack  80  of mail pieces  64  is moved onto jogger  40 , fingers  74  move up through slots  92  in bridge plate  90  to engage and separate the stack  80  into increments corresponding to the distance between fingers  74 . Timing belts  98  positioned in second slots  96  in one or more of extensions  94  urge the stack  80  across bridge plate  90 , facilitating the transfer of the stack onto the jogger.  
         [0024]    In one embodiment, as fingers  74  are advanced, jogger motor  66  simultaneously drives a cam  68  connected to a set of stack separating fingers  100 . As best shown in FIG. 3, as motor  66  advances the jogger, cam  68  drives stack separating fingers  100 , lifting the fingers  100  up in slots  92  in slotted plate  90  to engage the bottom of mail stack  80 . Separating fingers  100  slip between adjacent mail pieces and hold back the bottom edges of mail pieces behind the separating fingers creating a temporary gap. Timing belts  98  aid in the process, pushing the bottom of the stack  80  forward as fingers  100  are lifted by cam  68  to create the temporary separation in stack  80 . As jogger  40  advances, a set of fingers  74  rise up into the temporary gap, sliding into stack  80  without lifting mail pieces out of the stack. After fingers  74  have engaged the stack, cam  68  lowers separating fingers  100 , releasing the stack and allowing it to continue to advance. While as illustrated and described, separating fingers  100  are driven with cam  68 , the fingers could be actuated with a cylinder, solenoid or a similar device controlled by a timer or sensor detecting a finger  74  moving into position to be inserted into the stack.  
         [0025]    As best illustrated in FIG. 3, upper sprockets  44  and  46  are positioned in a horizontal plane above lower sprockets  48  and  50  and positioned closer together than lower sprockets  48  and  50 . This sprocket arrangement requires chains  42  to travel around lower sprocket  50 , reversing direction before traveling up and over sprocket  46 . Simultaneously, roller guide pins  78 , traveling in guide grooves  84 , orient brackets  70  as the brackets are carried by chains  42  around sprocket  50 . As will be appreciated by reference to FIGS. 3 and 6 in conjunction, as chains  42  travel around sprocket  50 , guide roller pins  78  traveling through guide grooves  84  cause the fingers  74  to move from a downwardly pointing orientation in the return segment  60  of path  52  to an upwardly pointing orientation in the sloped loading end  54  of path  52 . Thus, as shown, fingers  74  are oriented vertically before engaging stack  80 . Further, because the fingers  74  are oriented vertically as chains  42  transition from the sloped portion to the horizontal transport section  56 , the distance g 1 , between fingers  74   a  and  74   b  as the fingers engage the stack, increases to distance g 2.  The increase in gap size from g 1  to g 2  allows mail pieces  64  compressed and positioned on edge during loading or during transport with staging conveyor  36  to loosen, facilitating the edging process. As will be appreciated, the increase in spacing between fingers  74  as the fingers travel from the sloped loading end to the horizontal transport section  56  is proportional β, the upward angle of the sloped loading section  54 . (FIG. 3). Thus, the ratio of g 2 :g 1  may be increased or decreased for a particular application by increasing or decreasing β.  
         [0026]    As the mail pieces are conveyed across jogger  40  by fingers  74 , a plurality of rotating shafts  104  extending lengthways between fingers  74  and having at least one flattened surface  106  contact the bottom of stack  80 . As shafts  104  rotate, the shafts impart a bouncing or jostling motion to mail pieces  64  carried between the fingers to loosen and align the bottom edges of the mail pieces. It will be appreciated that the same bouncing or jostling effect may be imparted with an eccentrically formed or driven shaft. Shafts  104  are driven in clockwise direction as viewed from staging conveyor  36 , the rotation tending to edge the mail pieces against back wall  106  of jogger  40 . In the illustrated embodiment, an additional rotating shaft  108 , also having at least one flattened surface  110 , is mounted in wall  106  of jogger  40 . Shaft  108  rotates counterclockwise as viewed from staging conveyor  36  to urge mail pieces conveyed by jogger  40  down against shafts  104  as the mail pieces travel along the jogger. In addition to edging the mail pieces, the bouncing action provided by flattened surfaces  43  and  47  of shafts  42  and  45  tends to separate the mail pieces and cause any mail pieces that are held in an elevated position by pressure from abutting mail pieces to move down so that the bottom edge of such mail pieces are aligned with the rest of the stack of mail being carried by jogger  40 . Mail pieces  64  edged and loosed as described are transferred for further processing, such as singulation and sorting.  
         [0027]    While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments, as well as other embodiments of the invention, all within the spirit and scope of the invention will be apparent to persons skilled in the art upon reference to the description. It is, therefore, intended that the appended claims encompass any such modifications or embodiments.