Patent Publication Number: US-8967366-B2

Title: System and method for singulating and separating a plurality of non-oriented items

Description:
BACKGROUND 
     The present invention generally pertains to systems and method for singulating a batch of non-oriented items. Conventionally, after manufacturing items in bulk, the bulk or batch of items may need to be counted and/or packaged. Typically, a batch of items is dumped into a loading bin of an item transfer system. The dumped items are distributed in random orders and positions within the loading bin, thus giving the term “non-oriented items”. In order to efficiently count/package the non-oriented items, the item transfer system should singulate the non-oriented items, that is, place the items in single file order. An example conventional item transfer system will now be described with reference to  FIGS. 1A-B . 
       FIGS. 1A-B  are top views of a conventional item transfer system  100 . 
     As shown in  FIG. 1A , conventional item transfer system  100  includes a feeding area  102 , a conveyor  104  and a detector  106 . Feeding area  102  includes a loading bin  108  and a tapered chute  110 . Conveyor  104  includes a side  112 , a side  114 , an end  116 , an end  118 , a rail  120 , a rail  122  and a conveying surface  124 . 
     Chute  110  is disposed between loading bin  108  and end  116 . A batching bin  126  is disposed between end  118  and detector  106 . Rail  120  is disposed above conveying surface  124  and a distance d 1  from side  112 . Rail  122  is disposed above conveying surface  124  and a distance d 2  from side  114 . Rail  122  is separated from rail  120  by a width w 1 . Conveying surface  124  has a width w 2  between side  112  and side  114 . 
     Feeding area  102  feeds a plurality of non-oriented items  128  to conveyor  104 . Conveyor  104  conveys plurality of non-oriented items  128  from feeding area  102  to batching bin  126 . Detector  106  detects plurality of non-oriented items  128  as disposed in batching bin  126 . 
     In operation, plurality of non-oriented items  128  are dumped into loading bin  108 . As loading bin  108  fills up, a portion of plurality of non-oriented items  128  slide/tumble/roll down tapered chute  110  onto conveying surface  124  of conveyor  104 . For purposes of discussion, presume that conveyor  104  is a conveyor belt system operating so as to move conveying surface  124  in a direction from end  116  toward end  118  (as indicated by an arrow  139 ). 
     Once on conveying surface  124 , an item will convey toward end  118  and then fall into batching bin  126 . Batching bin  126  then holds deposited items  138 . Detector  106  is positioned so as to count the items that fall offend  118  into batching bin  126 . 
     Width w 1  between rail  120  and rail  122  permits only a single item to pass therebetween. For example, items  130 ,  132  and  134  each pass between rail  120  and rail  122  in a single file, i.e., they are singulated. In this manner, the non-oriented items may be singulated before they are deposited into batching bin  126 . This singulation assists detector  106  to count the items. 
     In some cases, it may be useful to orient plurality of non-oriented items  128  before they are deposited into batching bin  126 . For example, batching bin  126  may be able receive and stack items, provided the items are delivered in a predetermined manner. To orient plurality of non-oriented items  128  before they are deposited into batching bin  126 , width w 1  between rail  120  and rail  122  may be adjusted. This will be described with reference to  FIG. 1B . 
       FIG. 1B  illustrates a state of conventional item transfer system  100  wherein rail  120  and rail  122  have been adjusted to reduce the space therebetween. 
     For purposes of discussion, presume that each of non-oriented items  128  has a width, height and length. Further, presume that as shown in  FIG. 1B , width w 1  between rail  120  and rail  122  has been adjusted to the smaller of the width, height and length of on item. In this manner, each non-oriented item will not only be singulated as it conveys across conveyor  104 , each non-oriented item should be oriented in a predetermined manner. 
     A problem with conventional item transfer system  100  is clogging or jamming. For example, as illustrated in  FIG. 1B , a portion of plurality of non-oriented items  128  may be located in an area  144 , the area before entry into the passageway bounded by rail  120  and rail  122 . There is a likelihood that an item may be oriented such that it cannot fit between rail  120  and rail  122 . In such case, the item may block the passage way bounded by rail  120  and rail  122 , thus preventing other items from entering. 
     If item transfer system  100  becomes clogged/jammed with items, the clog must be cleared, for example manually by a user, before the system may continue to fill batching bin  126 . Such clogs drastically reduce efficiency of item transfer system  100 . Of course the shape of rails  120  and  122  may be designed to minimize clogging for a particular shape/size of item to be conveyed. However, if a batch of differently shaped/sized items is then used, then it is then more likely that the clogging will occur. Furthermore, as the speed of conveyor surface increases, the likelihood of item transfer system  100  becoming clogged/jammed increases. 
     Another problem with conventional item transfer system  100  is that the items may not be separated. For example, as illustrated in  FIG. 1B , some non-oriented items  128  may be located in an area  144 , the width between rails  120  and  122  is much smaller in order to more precisely singulate items  140 ,  142 ,  146 ,  148  and  150 . However, nothing in conventional item transfer system  100  ensures separation of the items, that is, a space between successive items in the direction of arrow  139 . In this example, items  146 ,  148  and  150  are not separated. As a result, detector  106  may incorrectly count the combination of items  146 ,  148  and  150  as a single item. 
     What is needed is a system and method that singulates, and separates, non-oriented items without clogging and that is item shape/size independent. 
     BRIEF SUMMARY 
     The present invention provides a system and method that singulates and separates non-oriented items without clogging and is item shape/size independent. 
     In accordance with an aspect of the present invention, a system is provided for transferring a plurality of non-oriented items, each item having an item height, an item width and an item length. The system includes a feeding area, a conveyor and a rail. The feeding area can accept the plurality of non-oriented items. The conveyor has a first end, a second end, a conveyor length disposed between the first end and the second end, a conveyor first side, a conveyor second side, a conveyor width disposed between the conveyor first side and the conveyor second side, and a conveyor ledge along the second side. The conveyor can move the plurality of non-oriented items in a direction along a conveyor path. The rail has a first rail end, a second rail end, a rail length disposed between the first rail end and the second rail end and a rail height. The rail is disposed above the conveyor and from the conveyor ledge at a distance equal to one of the item height, the item width and the item length. A first portion of the plurality of non-oriented items will convey along the conveyor path. A second portion of the plurality of non-oriented items will fall off the conveyor ledge. 
     Additional advantages and novel features of the invention are set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
    
    
     
       BRIEF SUMMARY OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and form a part of the specification, illustrate an exemplary embodiment of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings: 
         FIG. 1A  is a top view of a conventional item transfer system; 
         FIG. 1B  is a top view of the conventional item transfer system of  FIG. 1A , wherein the rails have been adjusted to a narrower width; 
         FIG. 2  is a top view of an example item transfer system in accordance with aspects of the present invention; 
         FIG. 3  is a side view of the item transfer system of  FIG. 2 ; 
         FIG. 4  is a timing chart of a portion of a conveyor of the item transfer system of  FIG. 2  at times t 0 , t 1 , t 2  and t 3 ; 
         FIG. 5  illustrates example driving signals as provided by a conveyor controller to drive a conveyor in the item transfer system of  FIG. 2 ; 
         FIGS. 6A-B  are side views of a portion of a conveyor of the item transfer system of  FIG. 2  at a times t 1  and t 3 , respectively; 
         FIG. 7  is an exploded top view of a portion of the item transfer system of  FIG. 2 ; 
         FIGS. 8A-C  illustrate exploded views of a portion of the item transfer system of  FIG. 2 , with the addition of a wiping arm in accordance with an aspect of the present invention; 
         FIG. 9  is a cross sectional view of the item transfer system of  FIG. 2  along line X-X; 
         FIG. 10  is a cross sectional view of a portion of  FIG. 9 ; 
         FIG. 11  is a cross sectional view of a modified embodiment of item transfer system of  FIG. 2  along line X-X; 
         FIG. 12  is a cross sectional view of a portion of  FIG. 11 ; 
         FIG. 13A  is a side view of a portion of the item transfer system of  FIG. 2  conveying items at an overall velocity v 1  and the detector being positioned so as to have line of sight; 
         FIG. 13B  is a side view of a portion of the item transfer system of  FIG. 2  conveying items at an overall velocity v 2  and the detector being positioned so as to have line the sight similar to  FIG. 13A ; and 
         FIG. 13C  is a side view of a portion of the item transfer system of  FIG. 2  conveying items at an overall velocity v 2  and the detector being positioned so as to have a new line of sight. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention provides a system and method for transferring items, wherein a plurality of aspects greatly increase efficiency over that of conventional item transfer systems. 
     In one aspect of the present invention, a rail is used to singulate non-oriented items on a conveyor. Contrary to conventional item transfer system  100  discussed above with reference to  FIG. 1 , in accordance with the present invention, the conveyor has a rail on one side and a ledge on the other. The items that travel along the path bounded by the rail and the ledge will be transferred to the batching bin, whereas the other items will fall off the ledge. A second conveyor is disposed to catch those items that fall off the ledge. The second conveyor is arranged to re-circulate the fallen items back into the feeding area. Therefore, because there is no second rail the item transfer system will not clog or jam. As such, an item transfer system in accordance with the present invention will run much more efficiently than conventional item transfer system  100  discussed above with reference to  FIG. 1 . 
     In another aspect of the present invention, a conveyor is controlled to “stutter” in order to separate items. In an example embodiment, a conveyor will move forward a predetermined amount, then move backward a predetermined amount and then again move forward a predetermined amount, wherein the overall motion is in a forward direction. This forward-backward-forward stutter prompts longitudinal separation of any items that may be touching. As such, a counter used with item transfer system in accordance with the present invention will more easily distinguish separate items. 
     In another aspect of the present invention, the rail shape and location is controllable in order to accommodate differently sized items. 
     In another aspect of the present invention, a wiping arm prevents stacked items from traversing along a conveyor. 
     In another aspect of the present invention, a conveyor is rotatable about an axis so as to bias items against the rail. This aspect accounts for items that are able to roll. 
     In another aspect of the present invention, an item retaining arm, which is rotatable about an axis, is positioned adjacent to the ledge of the conveyor. This aspect also prevents stacked items from traversing along the conveyor. 
     In another aspect of the present invention, the location of an item detector may be adjusted based on the velocity of the items traversing the conveyor. As such, a counter used with item transfer system in accordance with the present invention may more easily distinguish items. 
     In accordance with a first aspect of the present invention, a conveyor system and method is able to quickly and easily singulate non-oriented items. This will be further described with reference to  FIGS. 2-3 . 
       FIG. 2  is a top view of an example item transfer system  200 , in accordance with aspects of the present invention. 
     As shown in  FIG. 2 , item transfer system  200  includes feeding area  102 , a conveyor  202 , a conveyor  204 , a controller  206 , a detector  208 , a rail  210 , a rail controller  212 , an adjustment arm  214 , conveyor controller  216  and a conveyor controller  218 . Conveyor  202  includes a side  220 , a ledge  222 , an end  224 , an end  226  and a conveying surface  228 . Conveyor  204  includes a conveyor portion  230  and a conveyor portion  232 . Conveyor portion  230  includes a side  234 , a side  236 , an end  238 , an end  240  and a conveying surface  242 . Conveyor portion  232  includes a side  244 , a side  246 , an end  248 , an end  250  and a conveying surface  252 . 
     Controller  206 , detector  208 , rail controller  212 , conveyor controller  216  and conveyor controller  218  are illustrated as individual devices. However, in some embodiments, at least two of controller  206 , detector  208 , rail controller  212 , conveyor controller  216  and conveyor controller  218  may be combined as a unitary device. Further, in some embodiments, at least one of controller  206 , detector  208 , rail controller  212 , conveyor controller  216  and conveyor controller  218  may be implemented as a computer having tangible computer-readable media for carrying or having computer-executable instructions or data structures stored thereon. Such tangible computer-readable media can be any available media that can be accessed by a general purpose or special purpose computer. Non-limiting examples of tangible computer-readable media include physical storage and/or memory media such as RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium which can be used to carry or store desired program code means in the form of computer-executable instructions or data structures and which can be accessed by a general purpose or special purpose computer. For information transferred or provided over a network or another communications connection (either hardwired, wireless, or a combination of hardwired or wireless) to a computer, the computer may properly view the connection as a computer-readable medium. Thus, any such connection may be properly termed a computer-readable medium. Combinations of the above should also be included within the scope of computer-readable media. 
     Chute  110  is disposed between loading bin  108  and end  224 . Batching bin  126  is disposed between end  226  and detector  208 . Rail  210  is disposed above conveying surface  228  and a distance, determined by rail controller  212 , from side  112 . Rail  210  is separated from side  222  by a width w 1 . Conveying surface  228  has a width w 2  between side  220  and side  222 . 
     Feeding area  102  feeds a plurality of non-oriented items  128  to conveyor  202 . 
     Conveyor  202  conveys a first portion of plurality of non-oriented items  128  from feeding area  102  to batching bin  126 . Conveyor  202  may be any system or device that is operable to move an item from feeding area  102  to batching bin  126 . A non-limiting example embodiment of a conveyor includes a conveyor belt system. 
     Detector  208  detects the first portion of plurality of non-oriented items  128  as disposed in batching bin  126 . Detector  208  may be any known type of detector that is operable to detect an item. A non-limiting example embodiment of a detector includes an optical detector. 
     Rail  210  guides the first portion of plurality of non-oriented items  128  from feeding area  102  to batching bin  126 . Rail  210  may be any known structure that is operable to guide an item along a conveying path. In a non-limiting example embodiment, rail  210  includes a deformable material having sufficient structural integrity so as to prevent an item on conveyor  202  from traveling along an area  201  bounded by rail  210  and side  220 . Rail  210  additionally causes a second portion of plurality of non-oriented items  128  to fall off ledge  222  onto conveyor portion  230 . Specifically, an item&#39;s weight distribution is determined by its dimensions. When its center of gravity is hanging over the ledge, the item will topple off conveyor  202 . 
     Conveyor portion  230  conveys the second portion of plurality of non-oriented items  128  to conveyor portion  232 . Conveyor portion  230  may be any system or device that is operable to move an item that falls off ledge  222  to conveyor portion  232 . A non-limiting example embodiment of a conveyor portion includes a conveyor belt system. 
     Conveyor portion  232  conveys the second portion of plurality of non-oriented items  128  (that is, the fallen items) from conveyor portion  230  back to feeding area  102 . Conveyor portion  232  may be any system or device that is operable to move an item from conveyor portion  230  to feeding area  102 . A non-limiting example embodiment of a conveyor portion includes a conveyor belt system. 
     Controller  206  controls detector  208 , rail controller  212 , conveyor controller  216  and conveyor controller  218 . Controller  206  is in bi-directional communication with detector  208  via a detector control line  254 . Controller  206  is in bi-directional communication with rail controller  212  via an adjustment control line  256 . Controller  206  is in bi-directional communication with conveyor controller  216  via a conveyor control line  258 . Controller  206  is in bi-directional communication with conveyor controller  216  via a conveyor control line  260 . 
     Conveyor controller  216  drives conveyor  202 . Conveyor controller  216  is in communication with conveyor  202  via a conveyor driver line  262 . 
     Conveyor controller  218  drives conveyor portion  230  and conveyor portion  232 . Conveyor controller  218  is in communication with conveyor portion  230  and conveyor portion  232  via a conveyor driver line  264 . 
       FIG. 3  is a side view of item transfer system  200 . 
     In operation, plurality of non-oriented items  128  are dumped into loading bin  108 . When activated, a portion of plurality of non-oriented items  128  slide/tumble/roll down tapered chute  110  onto conveying surface  228  of conveyor  202 . For purposes of discussion, presume that conveyor is a conveyor belt system operating so as to move conveying surface  228  in an overall direction from end  224  toward end  226  (as indicated by an arrow  139 ). 
     Once on conveying surface  228 , an item will convey toward end  226  and then fall into batching bin  126 . Batching bin  126  then holds deposited items  138 . Detector  208  is positioned so as to count the items that fall offend  226  into batching bin  126 . 
     Width w 1  between rail  210  and ledge  222  permits only a single item to pass therebetween. For example, for purposes of discussion, take the case where items  266 ,  268 ,  270  and  272  are disposed on conveyor surface  228 . As conveyor surface moves in an overall direction from end  224  toward end  226 , items  266 ,  268 ,  270  and  272  additionally move in an overall direction from end  224  toward end  226 . Each of items  266 ,  268 ,  270  and  272  may ultimately rest on any particular position on conveyor surface  228  after sliding down chute  110  from loading bin  108 . In any event, as each item approaches rail  210 , rail  210  will force each item in a direction between rail  210  and ledge  122 . As a result, items  266 ,  268 ,  270  and  272  form a single file, i.e., they are singulated, as they convey along conveyor  202 . In this manner, the non-oriented items may be singulated before they are deposited into batching bin  126 , for example as represented by item  274 . This singulation assists detector  208  to count the items. In particular, as shown in  FIG. 3 , detector  208  is arranged to have a line of sight  312 , with which to count items as they fall offend  226  of conveyor  202 . 
     Returning to  FIG. 2 , rail  210  additionally forces some items to fall off ledge  222  and onto conveyor portion  230 . For example, item  276  was either not oriented so as to fit between rail  210  and ledge  222  or was originally positioned next to one of items  266 ,  268 ,  270  and  272 . As such, item  276  fell off ledge  222  and onto conveyor portion  230 . Because item transfer system  200  includes a ledge on a conveyor as opposed to a second rail, similar to rail  122  of conventional item transfer system  100  discussed above with reference to  FIGS. 1A-B , a plurality of non-oriented items will not clog or jam the system. Accordingly, item transfer system  200  can singulate non-oriented items more efficiently than conventional item transfer system  100  discussed above with reference to  FIGS. 1A-B . 
     Conveyor portion  230  conveys in a direction from end  238  to end  240  as indicated by arrow  278 . More easily seen with reference to  FIG. 3 , once item  276  falls off ledge  222  and onto conveyor portion  230 , conveyor portion  230  will return item  276  to conveyor portion  232 , which will then return item  276  to loading bin  108 . In other words, conveyor  204 , including conveyor portion  230  and conveyor portion  232 , re-circulates any portion of the non-oriented items, which are not singulated by rail  210  and ledge  222 , back to loading bin  108 . Once back in loading bin  108 , the re-circulated portion of the non-oriented items are again provided to conveyor surface  228  for singulation. The process continues until all the items are appropriately conveyed to batching bin  126 . 
     In the above-discussed non-limiting example embodiment, conveyor  204  includes two conveyor belt systems ( 230  and  232 ) that convey fallen items back to loading bin  108 . However, in other embodiments, conveyor  204  may be any system or mechanism that is operable to gather items that fall off ledge  222  and to convey the fallen items to back to a position on conveyor  202  prior to rail  210 . 
     In accordance with the aspect of the present invention discussed above with reference to  FIGS. 2-3 , as a result of using a single rail in conjunction with a ledge, there is no chance of the non-oriented items clogging item transfer system  200 . Accordingly, item transfer system  200  may be operated such that the velocity of conveyor surface  228  is much greater than the velocity of conveyor surface  124  of item transfer system  100  of  FIG. 1 . 
     In some cases, it also may be useful to longitudinally separate singulated items. As discussed above with reference to items  146 ,  148  and  150  of  FIG. 1B , if items are not separated, even though they are singulated, a detector may not accurately distinguish separate items. This may-introduce error in number of counted items. 
     In accordance with another aspect of the present invention, a conveyor system and method is able to separate items. In particular, a conveyor is driven with a stutter to promote longitudinal separation of any items that are not separated. For example, returning to  FIG. 2 , conveyor controller  216  may drive conveyor  202  by way of conveyor drive line  262 : in a forward direction (from loading bin  108  toward batching bin  126 ) for a first predetermined amount of time; in a backward direction (from batching bin  126  toward loading bin  108 ) for a second predetermined amount of time; and then in a forward direction (from loading bin  108  toward batching bin  126 ) for a third predetermined amount of time, so long as the overall motion is in the forward direction. This will be further described with reference to  FIGS. 4-6B . 
       FIG. 4  is a timing chart of a portion of conveyor  202  at a times t 0 , t 1 , t 2  and t 3 . 
     For purposes of explanation, at time t 0 , conveyor  202  is positioned so as to have portion  402  at a reference position. Later at time t 1 , surface  228  of conveyor  202  has moved in a direction, for example from end  224  toward end  226  (not shown), indicated by arrow  404  by a distance Δx 1 . 
     At this time, conveyor  202  is driven in a reverse direction. At time t 2 , surface  228  of conveyor  202  has moved in a reverse direction, for example from end  226  toward end  224  (not shown), indicated by arrow  406  by a distance −Δx 2 . The change of direction will induce motion of items on surface  228  and promote separation of any items that are not already separated. 
     The overall goal is to convey items from loading bin  118  to batching bin  126 . Accordingly, the overall motion must be in a direction from end  224  toward end  226 . As such, at this time, conveyor  202  is again driven in the forward direction. At time t 3 , surface  228  of conveyor  202  has moved in a forward direction, for example from end  224  toward end  226  (not shown), indicated by arrow  408  by a distance Δx 3 . The change of direction will again induce motion of items on surface  228  and again promote separation of any items that are not already separated. 
     The total distance, Δx T , that portion  402  will have traveled from time t 0  to time t 3  is calculated as:
 
Δ x   T   =Δx   1   −Δx   2   +Δx   3 .
 
     In some embodiments, Δx 1 =Δx 3 , whereas in other embodiments Δx 1 ≠Δx 3 . In some embodiments, Δx 2 =0, wherein the motion of conveyor  202  may be described as forward-stop-forward. This type of stutter will still induce motion of items on surface  228  and again promote separation of any items that are not already separated. 
     So a velocity of surface  228  of conveyor  220  may be constantly changing, going forward or going backward, based on the stutter. However, an overall velocity of surface  228  of conveyor  220  is the total distance, Δx 1 , that portion  402  traveled over the period defined by t 3 −t 0 . This overall velocity is the average velocity of the singulated and separated items as they move from feeding area  102  to batching bin  126 . Of course, some items may be recycled three or more times. However, only final displacement in the period matters. 
     The amount of stuttering may additionally be controlled by varying the velocity of conveyor  202  in both the forward and backward direction. The velocity may be determined by a drive signal provided by conveyor controller  216 . In non-limiting example embodiments, a drive signal provided by conveyor controller  216  is a digital signal. Further, in a non-limiting example embodiment, the velocity is controlled by controlling a duty cycle of a drive signal provided by conveyor controller  216 . This will now be described with reference to  FIG. 5 . 
       FIG. 5  illustrates example driving signals  502  and  504  as provided by conveyor controller  216  to drive conveyor  202 . In this example, driving signal  502  is used to move conveyor  202  in the direction indicated by arrow  404  of  FIG. 4  (in the forward direction from end  224  toward end  226 ). Driving signal  504  is used to move conveyor  202  in the direction indicated by arrow  406  of  FIG. 4  (in the reverse direction from end  226  toward end  224 ). 
     Driving signal  502  has a period P 1 , wherein the active state  506  has a width A 1  and the non-active state  508  has a width N 1 . Driving signal  504  has a period P 2 , wherein the active state  510  has a width A 2  and the non-active state  512  has a width N 2 . Because active state  506  of driving signal  502  is larger than driving state  510  of driving signal  504 , driving signal  502  will drive conveyor  202  for a longer time than that of driving signal  504 . Accordingly, returning to  FIG. 4 , driving signal  502  will “move” portion  402  a greater distance in the forward direction than driving signal  504  will “move” portion  402  in a reverse direction. 
     A pulse-width modulation scheme to control the stuttering of conveyor  202  is but one non-limiting example embodiment. Any known driving method may be used, non-limiting examples of which include pulse-number modulation and pulse-height modulation. In any event, the sudden change of velocity or stuttering of conveyor  202  promotes separation of items on conveyor surface  228 . This will be described with reference to  FIGS. 6A-B . 
       FIGS. 6A-B  are side views of a portion of conveyor  202  at times t 1  and t 3 , respectively. 
     For purposes of discussion, as shown in  FIG. 6A , at time t 1 , conveyor  202  has items  602 ,  604 ,  606 ,  608 ,  610 ,  612 ,  614  and  616  thereon. Item  602  is separated from item  604  by a spacing  618 . Item  606  is separated from item  608  by a spacing  620 . Item  608  is separated from item  610  by a spacing  622 . Item  610  is separated from item  612  by a spacing  624 . Item  604  is not separated from item  606 . Similarly, item  614  is not separated from either item  612  or item  616 . 
     Although items  602 ,  604 ,  606 ,  608 ,  610 ,  612 ,  614  and  616  may be singulated, non-separated items  604  and  606  and non-separated times  612 ,  614  and  616  may be inaccurately counted as single items by counter  208 . By driving conveyor  202  with a stutter, as discussed above with reference to  FIGS. 4 and 5 , item  604  may be separated from item  606  and item  614  may be separated from items  612  and  616 . 
     Recalling from the discussion above with reference to  FIGS. 4 and 5 , at time t 3 , conveyor  202  will have been driven in a forward direction, in a reverse direction and then again in a forward direction. This stuttering promotes separation of items on conveyor surface  228 . As shown in  FIG. 6B , at time t 3 , item  602  is separated from item  604  by a spacing  626 . Item  604  is separated from item  606  by a spacing  628 . Item  606  is separated from item  608  by a spacing  630 . Item  608  is separated from item  610  by a spacing  623 . Item  610  is separated from item  612  by a spacing  634 . Item  612  is separated from item  614  by a spacing  636 . Item  614  is separated from item  616  by a spacing  638 . 
     Having all of items  602 ,  604 ,  606 ,  608 ,  610 ,  612 ,  614  and  616  separated, detector  208  may more accurately count the items. 
     In accordance with another aspect of the present invention, a conveyor system and method is able to accommodate differently sized non-oriented items. This will be further described with reference to  FIG. 7 . 
       FIG. 7  is an exploded top view of area  203  of  FIG. 2 . 
     As shown in  FIG. 7 , an item  706  is being conveyed from loading bin  108  to batching bin  126 . For purposes of discussion, presume that item  706  additionally has a length l i , wherein l i &gt;w i . In order to have items singulated into uniform arrangements, rail  210  is set at a distance from ledge  222 , wherein the distance corresponds to the smaller of the dimensions of item  706 . Accordingly, rail  210  is disposed distance w i  from ledge  222 . In this manner, if an item were to be situated in any position other than that similar to item  706 , then the item will be forced off ledge  222 . For example, if an item  708  were situated in a position such that its length were perpendicular to the length of item  706 , then item  708  would be forced off ledge  222 , onto conveyor  204  for re-circulation. 
     In the case where different items are to be transferred from loading bin  108  to batching bin  126 , and the different items have different dimensions from item  706 , then the position and shape of rail  210  may have to be changed. To accommodate such a change, rail controller  212  may extend or retract adjustment arm  214 . For example, if the new items have a smaller dimension for sorting than item  706 , rail controller  212  may extend adjustment arm  214 . This would in turn change the position and shape of rail  210  as indicated by dotted line  702 . Similarly, if the new items have a larger dimension for sorting than item  706 , rail controller  212  may retract adjustment arm  214 . This would in turn change the position and shape of rail  210  as indicated by dotted line  704 . 
     Even if plurality of non-oriented items  128  become singulated, for example as described above with reference to  FIG. 2 , and separated, for example as described above with reference to  FIGS. 4-6 , there is a chance non-oriented items may stack on each other. In such a case, detector  208  may count two stacked items as a single item. 
     In accordance with another aspect of the present invention, a conveyor system and method is able to prevent stacking of non-oriented items. This will be further described with reference to  FIGS. 8A-C . 
       FIGS. 8A-C  illustrate exploded views of area  203  of  FIG. 2 , with the addition of a wiping arm  802 .  FIG. 8A  is a top view of area  203  at a time T 1 .  FIG. 8B  is a side view of area  203  at time T 1 .  FIG. 8C  is a side view of area  203  at time T 2 . 
     As shown in  FIG. 8A , wiping arm  802  is disposed to extend across conveyor  202  above rail  210 . For purposes of discussion, presume that each item has an item height H i . As shown in  FIG. 5B , wiping arm  802  is disposed above conveyor surface  228  at a height to correspond with the height of the items to be singulated and separated. In this example, wiping arm  802  is disposed higher than height H i  above conveyor surface  228  in order to permit a single item to pass. At time T 1 , item  804  is disposed on conveyor  202  and an item  806  is stacked on item  804 . At this point in time, item  804  passes under wiping arm  802 , whereas item  806  is blocked by wiping arm. 
     Eventually, as conveyor  202  continues to transfer item  804  in direction  139 , wiping arm  802  will wipe item  806  off the top of item  804 . 
     As shown in  FIG. 8C , at time T 2 , item  806  has been wiped off item  804 . Item  806  may fall onto conveyor  202  and continue in direction  139  or may fall onto conveyor  204  and be re-circulated. 
     There may be situations where items to be singulated and separated have a side that is not flat, which may induce instances of the items rolling off conveyor  202 . Conveyor  202  may tilt in order to use gravity to bias such items toward rail  210 . 
     In accordance with another aspect of the present invention, a conveyor system and method is able to tilt to accommodate non-oriented items that may roll. This will be further described with reference to  FIGS. 9-10 . 
       FIG. 9  is a cross sectional view of item transfer system  200  along line X-X of  FIG. 2 . 
     As shown in  FIG. 9 , conveyor  202  and rail  210  are situated about an axis  902  such that conveying surface  228  is on a plane parallel with or substantially parallel with a plane of conveying surface  242  of conveying portion  230 . 
     For purposes of discussion, presume that items to be transferred on item transfer system  200  have a circular cross section, such as ears of corn. There is a chance that item  906  may roll off conveyor  202  and onto conveyor portion  230 . Although item  906  would eventually re-circulate and return to conveyor  202 , this decreases the efficiency of operation of item transfer system  200 . 
     To prevent item  906  from rolling off conveyor  202  and onto conveyor portion  230 , conveyor  202  may be tilted about axis  902  in order to bias item  906  against rail  210 . This will be described with reference to  FIG. 10 . 
       FIG. 10  is a cross sectional view of portion  904  of  FIG. 9 , which includes conveyor  202  and rail  210 . In  FIG. 10 , conveyor  202  and rail  210  are tilted about axis  902  in a direction indicated by arrow  1002 . 
     Gravity biases item  906  in a direction indicated by arrow  1004 . A component of gravity will bias item  906  against rail  210  as indicated by arrow  1006 . This component of gravity bias prevents items  906  from rolling off conveyor  202 . In other words, the tilt shifts a center of gravity of rectilinear items, which otherwise might have fallen over ledge  222 . 
     In some embodiments, conveyor  202  may be rotated manually. In other embodiments, conveyor  202  may be rotated by conveyor controller  216 , as instructed by controller  206 . 
     There may be instances where stacked items are forced off conveyor  202  without the need for a wiping arm, such as wiping arm  802  discussed above with reference to  FIG. 8 . 
     In accordance with another aspect of the present invention, a conveyor system and method is able to tilt to prevent stacking of non-oriented items. This will be further described with reference to  FIGS. 11-12 . 
       FIG. 11  is a cross sectional view of a modified embodiment of item transfer system  200  along line X-X of  FIG. 2 . 
     As shown in  FIG. 11 , conveyor  202  and rail  210  are situated about an axis  902  such that conveying surface  228  is on a plane parallel with or substantially parallel with a plane of conveying surface  242  of conveying portion  230 . Further, an item retaining arm  1102  may be disposed adjacent to ledge  222 . 
     For purposes of discussion, presume that items to be transferred on item transfer system  200  have a propensity to stack, such as washers. There is a chance that item  1106  may have a second item  1108  stacked thereon. 
     To remove item  1108  from item  1106 , conveyor  202  may be rotated about axis  902  in order to slide item  1108  off item  1106  and onto conveyor portion  230 . This will be described with reference to  FIG. 12 . 
       FIG. 12  is a cross sectional view of portion  1104  of  FIG. 11 , which includes conveyor  202  and rail  210 . In  FIG. 12 , conveyor  202  and rail  210  are rotated about axis  902  in a direction indicated by arrow  1202 . 
     Gravity biases item  1106  in a direction indicated by arrow  1204 . A component of gravity will bias item  1106  against retaining arm  1102  as indicated by arrow  1206 . Similarly, gravity biases item  1108  in a direction indicated by arrow  1208 . A component of gravity will bias item  1108  toward conveyor portion  230  as indicated by arrow  1210 . This component of gravity forces item  1108  to fall onto conveyor portion  230 . 
     In some embodiments, retaining arm  1102  is fixed to a single position (height) at ledge  222 . In other embodiments, the height of retaining arm  1104  may be adjusted at ledge  222  to accommodate a range of item heights. 
     The aspects discussed above with respect to  FIGS. 2-12  address singulating and separating items. However, depending on conveyor  202  speed, detector  208  may have trouble distinguishing distinct between items as items are deposited in batching bin  126 . 
     In accordance with another aspect of the present invention, a conveyor system and method is able to adjust a detector position based on the velocity of the items leaving the conveyor. This will be further described with reference to  FIGS. 13A-C . 
       FIG. 13A  is a side view of conveyor  202  conveying items at an overall velocity v 1  and detector  208  positioned so as to have line of sight  312 . 
     As shown in the figure, items will have a trajectory following dotted arrow  1302 . So long as a spacing  1304  between items is sufficient, detector  208  distinguishes between items. However, when the overall velocity of the conveyed items increases, the trajectory of the items as they leave conveyor  202  changes. 
       FIG. 13B  is a side view of conveyor  202  conveying items at an overall velocity v 2  and detector  208  positioned so as to have line of sight  312 . As shown in the figure, items will have a trajectory following dotted arrow  1306 . In this case, v 2 &gt;v 1  such that dotted arrow  1306  has a smaller vertical gradient than that of dotted arrow  1302  of  FIG. 13A . 
     The trajectory of items as shown in  FIG. 13B  are such that there is likelihood that detector  208  will not be able to distinguish distinct items. In the illustrated example, a distance  1308  separates items  1310  and  1312 . As shown, in  FIG. 13B , line of sight  312  intercepts item  1310  and  1312  because distance  1308  and the trajectory of items  1310  and  1312  (as shown by arrow  1306 ) are such that detector  208  cannot distinguish between items  1310  and  1312 . 
       FIG. 13C  is a side view of conveyor  202  conveying items at an overall velocity v 2  and detector  208  positioned so as to have a line of sight  1314 . Because detector  208  has moved to a new position, new line of sight  1314  enables detector to distinguish item  1310  from item  1312 . 
     The foregoing description of various preferred embodiments of the invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The example embodiments, as described above, were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.