Abstract:
An apparatus for uniformly distributing parts on a conveyor surface which includes a storage bin for holding randomly oriented parts in bulk, a conveyor adjacent the storage bin for acquiring a fragment of the randomly oriented parts in the storage bin and delivering that fragment of randomly oriented parts to a chute, a vibratory conveyor receiving the fragment of randomly oriented parts from said chute, and a belt conveyor for receiving the randomly oriented parts from said vibratory conveyor. The vibratory conveyor includes at least one rib projecting upward therefrom and extending across at least a section of the vibratory conveyor perpendicular to the direction of conveyance, the at least one rib acting as a flow obstruction to cause the randomly oriented parts traveling on the vibratory conveyor to gather and spread across a width of said vibratory conveyor to thereby spread more uniformly on the vibratory conveyor after passing over the at least one rib.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a divisional of U.S. application Ser. No. 09/026,078, filed Feb. 19, 1998 now U.S. Pat. No. 6,116,409. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to automated manufacturing systems and, more particularly, to flexible parts feeding systems for automated inspection and/or manufacturing. 
     BACKGROUND OF THE INVENTION 
     Parts feeders used in the manufacturing industry are well known. Typically, such parts feeders comprise various types of hoppers, vibratory-type bowls or centrifugal-type bowls containing a bulk source of parts. These devices are used to separate and orient parts and properly present them to a subsequent process or assembly device. Such devices are typically capable of feeding one part type or a very small family of part types. 
     The use of a vision-based flexible parts feeders is a relatively new phenomenon in the manufacturing industry which is gaining credibility. With the use of such vision-based parts feeders, companies are able to make their manufacturing systems more flexible by designing feeders with the capability to feed a very wide variety of parts. Doing so allows for a more cost effective means to automate the production of smaller volume products. Typically, in operation, such parts feeders deliver bulk parts from a source to a transport surface for inspection and subsequent picking therefrom by a robot. Preferably, a single camera is used to inspect the separated parts on the transport surface. The inspection is primarily used to identify which parts may be successfully grasped by a robot as well as the location of each identified “pickable” part. Flexible parts feeders also typically include a system for recirculating parts which cannot be grasped by the robot. 
     The performance and maximum feed rate of a flexible parts feeder is closely related to the feed rate, distribution, separation, stability and orientation of parts passing into the camera field of view as well as the performance of the vision system used therewith. Controlling these part attributes results in the ability to maximize the number of parts that can be inspected and successfully grasped by a robot in a given amount of time. The part feed rate into the camera field of view is preferably very consistent and controlled by the device which introduces parts from the bulk source. The distribution and separation of parts being inspected is preferably controlled by the conveyance portion of the feeder preceding the camera field of view. In addition, this conveyance portion also typically dictates the distribution, separation and, to some extent, the orientation (or number of stable states) of parts passing into the field of view which all affect the number of pickable parts during a given amount of time. The stability of parts as they pass into the camera field of view is also determined by the same conveyance portion and the means by which parts are transferred from the conveyance portion to the said transfer surface. It should be understood that if parts are bouncing around or not resting in the most stable orientations, additional part settle time is needed before inspection may occur which reduces feeder throughput. 
     One flexible parts feeder known in the prior art includes a series of tiered belts and an elevating bucket device for circulation of parts within the feeder. This parts handling technique results in a flow of parts through the feeder which is inconsistent due to a non-uniform part feed rate into the camera&#39;s field of view. In addition, parts are dropped from one belt to another in a way that results in a less than desirable part separation and additional undesirable part resting states. The belt which serves as the inspection surface is typically indexed back and forth to better spread out parts or is rapidly indexed to present more parts to the inspection camera. As a result additional parts settling time is required prior to inspection which limits performance and overall feeder throughput. 
     Another type of flexible parts feeder which is known in the prior art incorporates two pile-covered vibratory conveyor devices. In this type of parts feeder, a quantity of bulk parts is circulated on two opposing and side-by-side vibratory conveyors to move bulk parts in a generally circulating pattern. The conveyor vibrations and pile material are used to both convey and distribute parts into the field of view of a downward-looking camera which is located directly over one portion of one of the conveyor surfaces. The robot grasps parts directly off of the vibratory conveyor surface. This requires that the part must settle out prior to part inspection and grasping thereby decreasing feeder performance. Further, due to the nature of the bristle geometry of the pile material used for the vibratory conveyor, very small parts or parts with sharp protrusions tend to lodge in the pile material. As a result of the method employed to recirculate parts, control of part feed rate and part distribution through the feeder, and parts “sticking” in the pile material, feeder through put is limited (average feed rates in the range of 15 to 40 parts per minute). 
     Still another flexible parts feeder available on the market today includes a vibratory hopper for introducing parts from a bulk source, a relatively violent shake platen, a set of adjustable “fences” or gates for partially orienting parts and urging parts into a substantially single file prior to inspection and a belt which is indexed with rapid acceleration and deceleration to transport parts from the platen to the camera inspection area. Primarily due to the process of forming of the single file and the rapid indexing of the belt the rate of “pickable” parts presented to the camera field of view is limited to around 20 to 30 parts per minute. 
     SUMMARY OF THE INVENTION 
     It is, therefore, an object of the present invention to provide a parts feeder to an inspection and/or robotic-assisted operation which can achieve higher feed rates of separated parts for inspection or acquisition. 
     It is a further object of the present invention to provide a vibratory conveyor for use with a parts feeder which effectively spreads out bulk parts onto a surface for inspection in a way that increases the uniform distribution of separated parts on the surface and reduces the amount of time required for the parts to achieve a stable state after the parts are fed onto the final inspection belt surface. 
     Yet another object of the present invention is to provide a vibratory conveyor which efficiently spreads out bulk parts in a relatively short conveyor length. 
     Still another object of the present invention is to provide a vibratory conveyor which presents separated parts at a high feed rate without increasing inspection belt velocity. 
     Another object of the present invention is to provide a vibratory conveyor apparatus that includes a series of ribs protruding upward from the conveyor surface which serve to more quickly spread out and separate bulk parts in both a width-wise and length-wise direction as they pass over the conveyor surface thereby reducing required conveyor length. 
     Briefly stated, the foregoing and numerous other features, objects and advantages of the present invention will become readily apparent upon a review of the detailed description, claims and drawings set forth herein. These features, objects and advantages are accomplished through the combination of a belt conveyor preferably driven at a constant speed, and a vibratory conveyor which preferably includes flow obstructions which serve to increase the uniform distribution of separated parts and thus, the density of separated parts per unit area of the belt conveyor. It should be understood that effective inspection and/or acquisition of parts can only occur with separated (non-overlapping) parts. The vibratory and belt conveyors are preferably used in conjunction with a bulk elevator and a reciprocating-plate type hopper. The bulk elevator is used to separate a quantity of parts from a storage bin and deliver that quantity to a staging platform. The reciprocating-plate type conveyor separates smaller portions of the parts from the staging platform and delivers them to the vibratory conveyor. The vibratory conveyor, which has a relatively vertical shake angle, includes one or more obstructions protruding up from the surface thereof. Such obstructions are generally transverse to the direction of movement of the parts on the vibratory conveyor. The vibratory conveyor aids in separation of parts from one another and causes individual parts to seek the parts&#39; most stable resting orientations. The obstructions serve to temporarily “dam up” the flow of parts which tends to very quickly spread out parts across the width of the conveyor. It has also been shown through experimentation that these obstructions tend to provide a much greater resistance to larger “clumps” of parts than those parts which are partially separated from one another. As a result, the obstructions effectively break up and spread out “clumps” of parts along the length of the vibratory conveyor. Due to both effects, parts exit the vibratory conveyor with a much greater density of singulated (separated inspectable and/or pickable) parts which serves to increase the feed rate of singulated parts presented to the inspection area and/or the picking area for picking by the robot. In other words, although the obstructions decrease the overall distribution density of parts on the vibratory conveyer (because clumps of parts and overlapping parts are substantially eliminated), the overall distribution density of separated and therefore, inspectable and/or pickable parts is increased. This increase in distribution density of separated parts results in the desired higher feed rate, and this higher feed rate of separated parts is accomplished without increasing the speed at which parts are conveyed. The vibratory conveyor drives the parts to be delivered to the belt conveyor which is preferably driven at a constant speed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the parts feeder of the present invention with the electromagnetic actuator and associated support structure removed therefrom for simplicity. 
     FIG. 2 is a schematic cross-sectional schematic view of the storage bin and reciprocating plate parts elevator section of the apparatus depicted in FIG.  1 . 
     FIG. 3 is a side elevational view of the vibratory conveyor section of the apparatus depicted in FIG. 1 with a sidewall partially removed therefrom. 
     FIG. 4 is a side elevational view of a portion of the vibratory conveyor surface with an exemplary rib projecting therethrough. 
     FIG. 5 is a perspective view of the exemplary rib shown in FIG.  4 . 
     FIG. 6 is a top plan view schematic of the apparatus depicted in FIG. 1 illustrating parts distribution density in the conveyance loop formed by the apparatus of FIG.  1 . 
     FIG. 7 is a top plan view of the continuous belt conveyor section of the apparatus of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning first to FIG. 1, there is shown a perspective view of the flexible parts feeder  10  of the present invention. The flexible parts feeder  10  includes a storage bin  12  which serves to hold the reservoir of parts. Parts are removed from storage bin  12  with a reciprocating plate parts elevator section  14  which will be described more fully hereinafter. The reciprocating plate parts elevator section  14  delivers parts to chute  16 . Chute  16  is mounted to vibratory conveyor  18  and is inclined such that parts delivered thereto slide down chute  16  and onto vibratory conveyor  18 . Parts conveyed along the length of vibratory conveyor  18  are delivered to belt conveyor  20  which is a typical endless loop belt conveyor system. As will be discussed in more detail hereinafter, a portion of belt conveyor  20  is in the field of view of an image capturing means (not shown) which may be used for inspection and/or identification of parts. Also not shown is a robot which “picks” the desired parts from belt conveyor  20 . Parts not picked from belt conveyor  20  fall therefrom into trough  22 . Such parts slide down trough  22  into storage bin  12 . In such manner, parts not picked by the robot are recirculated through apparatus  10  such that they will once again pass through the camera&#39;s field of view on belt conveyor  20 . 
     Looking next at FIG. 2, there is schematically depicted a cross-sectional view of the storage bin  12  and reciprocating plate parts elevator section  14 . As can be seen, a plurality of randomly oriented parts  24  reside in storage bin  12  which are introduced thereto through the open top of storage bin  12 . The randomly oriented parts  24  may all be identical parts, or may be two or more different types of parts. The bottom wall  26  of storage bin  12  is inclined toward elevator section  14 . The sidewalls  28  of storage bin  12  may also be inclined toward the base  30  of bottom wall  26 . In such manner, the parts  24  are funneled toward the base  30  to press against the front face  32  of bulk elevator  34 . Bulk elevator  34  is preferably supported by linear bearings  36  and is preferably actuated by a reversing lead screw  38 , a belt  40  and a motor  42 . Bulk elevator  34  is driven in a reciprocating motion by motor  42  such that on downward movement, a plurality of parts  24  fall by gravity onto the top surface  44  of bulk elevator  34 . On its upward stroke, bulk elevator  34  rises to a level such that the top surface  44  is substantially even with the top surface  46  of stationary platform  48 . Thus, when bulk elevator  34  reaches the peak of its upward stroke, the parts  24  supported thereon fall by gravity onto the top surface  46  of staging platform  48 . Residing adjacent to staging platform  48  is a reciprocating plate conveyor  50 . Reciprocating plate conveyor  50  is preferably that conveying apparatus taught in U.S. Pat. No. 5,385,227. Such conveying apparatus is manufactured by Omnifeed Systems, Inc., of Emmanaus, Pa. Reciprocating plate conveyor  50  includes a series of opposingly reciprocated plates  52  which are actuated in a synchronized way (by means not shown) such that parts  24  are taken from top surface  46  of staging platform  48  and raised and transferred to each successive reciprocating plate  52  to ultimately deliver parts  24  into chute  16 . The rate at which bulk elevator  34  reciprocates should be adjusted so that there is always some minimum quantity of parts  24  residing on top surface  46 . It should, of course, reciprocate at a rate which is substantially less than the rate at which reciprocating plates  52  reciprocate. A portion of those parts  24  residing on top surface  46  then slide onto the lowest reciprocating plate  52  when that lowest reciprocating plate  52  reaches the bottom of its downstroke during reciprocation. Through a series of transfers between subsequent reciprocating plates  52 , parts  24  are elevated to the discharge area to fall into chute  16 . The quantity of parts which can be held on top surface  46  of staging platform  48  should be greater than the quantity of parts  24  which can be held on top of any of reciprocating plates  52 . It is believed that the ratio of the surface area of top surface  46  to the surface area of the top of a reciprocating plate  52  should be in the range of from about 2:1 to about 3:1. The use of bulk elevator  34  in combination with staging platform  48  aid in ensuring that a small and consistent quantity of parts  24  is fed through elevator section  14  to chute  16 . Further, the use of bulk elevator  34  results in a decrease in the churning of parts in the lower portion of storage bin  12  when storage bin  12  is relatively full. Merely extending reciprocating plate conveyor  50  down into the full depth of storage bin  12  would have the disadvantage of having one or more reciprocating plates  52  which at the top of their respective strokes would still be below the level of parts  24  in storage bin  12 . The resulting churning of parts  24  can potentially damage some parts  24 . It should be understood that the series of transfers from storage bin  12  to bulk elevator  34  to staging platform  48  and to each successive reciprocating plate  52  tends to detangle the randomly oriented parts  24  from one another in a very gentle way. The rate at which reciprocating plates  52  reciprocate should be adjusted so that some average desired part feed rate is obtained. 
     Other elevating-type conveyors may be substituted for reciprocating plate conveyor  50  and/or bulk elevator  34 . One example of such an elevating-type conveyor which could be used to acquire parts  24  from storage bin  12  and deliver such parts  24  to chute  16  is a cleted conveyor belt. 
     Turning next to FIG. 3, there is shown the side elevational schematic of the vibratory conveyor section  18  of the present invention. Vibratory conveyor section  18  includes a support member or upper frame  54  with a generally planar top surface. The term “generally planar” top surface as used herein is intended to mean a surface comprised of a single surface or multiple surfaces, all of which reside in one plane. In other words, the top surface of support member  54  may be either continuous or discontinuous. An example of a support member  54  with a discontinuous top surface would be an extruded aluminum structural member with a series of spaced apart, parallel T-shaped sections forming the top surface. A second example of a support member  54  with a discontinuous top surface would be a support member  54  comprised of a plurality of spaced apart, parallel I-bars with the top surfaces of the individual I-bars residing in the same plane. The top surface of support member  54  is covered or partially covered with a vibratory surface material which is preferably a pile material  55  which includes a base  56  with fibers  57  projecting therefrom (see FIG.  4 ). Bordering each side of support member  54  is a side wall  58  which serves to contain parts  24  therebetween. Pile material  55  is preferably Brushlon® as manufactured by  3 M Company of St. Paul, Minn. Brushlon® has fibers which are oriented about 15° to 20° from vertical. The individual fibers  57  of pile material  55  are reoriented in the range of from about 50° to about 80° from vertical by compressing the material while heating. As a result, parts  24  are supported on the sides of the individual fibers or bristles  57  and not on the ends of the bristles  57  as is typical of vibratory conveyors of the prior art. The individual fibers or bristles  57  are all inclined toward the downstream direction and the continuous belt conveyor  20  as indicated by arrow  59 . The pile material  55  preferably includes a backer member  60  made of a ferromagnetic sheet metal which is adhered to the underside of pile material  55 . There is a magnetic vinyl sheet  61  which is affixed to support member  54 . In such manner, the pile material  55  through backer member  60  can be magnetically coupled to support member  54 . This method of coupling the pile material  55  to support member  54  provides an easy means to remove and/or replace pile material  55 . Further, the magnetic coupling allows for more intimate planar contact between the two members as opposed to the Velcro®-type arrangement typically used to fasten pile material to the surfaces of a vibratory conveyor. It should be understood that the positions of backer member  60  and magnetic vinyl sheet  61  can be reversed. In other words, a backer member  60  made of a ferromagnetic sheet metal can be adhered to the support member  54  and the magnetic vinyl sheet  61  can be affixed to the underside of pile material  55 . Further, a second magnetic vinyl sheet could be substituted for backer member  60 . The magnetic coupling arrangement of the present invention results in a more efficient transfer of energy during vibration over Velcro®-type interfaces which generally act to dampen vibration. Further, the magnetic coupling arrangement of the present invention allows for much easier positioning of pile material  55  than is afforded by Velcro®-type interfaces. Those skilled in the art of vibratory conveyors will recognize that a smooth surfaced material such as steel, plastic or rubber may be substituted for pile material  55 . Using a smooth surfaced material will likely require an adjustment of vibration amplitude depending on the specific parts  24  being conveyed. 
     Projecting upward from support member  54  is at least one rib  62  and preferably, a series of ribs  62 . Each rib  62  preferably traverses the width of pile material  55  and is preferably generally perpendicular to each of sidewalls  58 . However, it should be understood that each rib  62  could be formed in two or more sections with a gap between adjacent sections and between the end sections and sidewalls  58 . Thus, a single rib  62  may be formed, for example, by an array of closely spaced, projecting nubs arranged in one or more lines across the width of pile material  55  wherein the nubs in adjacent lines may be staggered from one another. Any gaps left in ribs  62  should preferably be small enough such that individual parts  24  could not pass directly therethrough without having to pass over at least a portion of rib  62 . Each of ribs  62  may project to the same height above pile material  55 . However, it is preferred that ribs  62  are arranged in a such way that the height of each successive rib  62  moving toward the downstream is slightly less than the height of the preceding rib  62 . With the ribs  62  decreasing in height, less effort is required to get individual parts over each successive rib  62 . Each rib  62  aids in spreading the individual parts across the width pile material  55 . Thus, each rib  62  aids in obtaining a more optimum distribution density of parts for picking by a robot while being less of an obstacle to the forward movement of parts on vibratory conveyor section  18 . The term “generally perpendicular” as used herein with reference to ribs  62  is intended to include ribs  62  which are perpendicular to each of sidewalls  58  and ribs  62  which are within about 5° of being perpendicular to each of sidewalls  58 , as well as ribs  62  formed by arrays of nubs wherein the array of nubs is perpendicular to each of sidewalls  58 , or the array of nubs is within about 5° of being perpendicular to each of sidewalls  58 . 
     One possible design for ribs  62  is depicted in FIGS. 4 and 5. In such exemplary design, rib  62  is constructed from a formed sheet metal strip  64  to create a base portion  63  and an inverted V-shaped portion  65 . Rib  62  is retained in place by trapping base portion  63  between backer member  60  and magnetic vinyl sheet  61 . Thus, if sheet metal strip  64  is made from a ferromagnetic material, then rib  62  is both mechanically and magnetically coupled between backer member  60  and magnetic vinyl sheet  61 . The front face  67  of rib  62  may be vertical but preferably resides at an angle of from about 10° to about 30° from vertical toward the direction of flow of parts  24 . Depending on the shape and size of parts  24  being conveyed, a vertical front face  67  may result in trapping some parts  24 . The actual height of ribs  62  should be determined empirically for the specific parts  24  being conveyed. 
     Returning to FIG. 3, support member  54  is connected to lower frame  70  by means of flexures  74 . Extending from support member  54  is bracket  76 . Electromagnetic actuator  72  is connected to bracket  76  via flexures  78  and is thus suspended from support member  54 . Flexures  74  and flexures  78  are preferably oriented such that they reside at an angle in the range of from about 10° to about 30° from the horizontal. This results in an angle of vibration θ of support member  54  in the range of from about 10° to about 30° from vertical. Flexures  74  and flexures  78  which are generally equivalent to leaf springs are preferably made from Scotchply® (which is a non-woven, fiberglass reinforced, epoxy resin material) as manufactured by 3M of St. Paul, Minn. Other materials such as steel may be used. Through electromagnetic actuator  72 , support member  54  and pile material  55  affixed thereon is vibrated in a more vertical direction than typical vibratory conveyors of the prior art. One suitable electromagnetic actuator  72  for use with the present invention is the F-T01A electromagnetic actuator as manufactured by the FMC Material Handling Equipment Division, Homer City, Pa. It is available as a unit complete with flexures  78 . Those skilled in the art will recognize that electromagnetic actuator  72  will include means for adjusting the amplitude of vibration imparted to vibratory conveyor  18 . Through the proper adjustment of vibration amplitude most unstable part orientations can be eliminated. 
     In operation, a quantity of parts  24  slides down inclined chute  16  through both gravity and the vibrations imparted thereto by electromagnetic actuator  72 . The vibrations transmitted through pile material  55  cause parts  24  received via chute  16  to begin to spread out on pile material  55  and move toward the first rib  62 . The more vertical direction of the vibration tends to spread out the parts  24  more effectively without increasing the speed of the parts  24  as they are conveyed over the pile material  55 . Further, it should be appreciated that the relatively flat angle at which the individual fibers are oriented on pile material  56  substantially eliminates the risk of parts becoming stuck or lodged in the pile material  56  as can sometimes occur when conveying parts  24  possessing sharp features over a pile material with fibers which are more vertically oriented. 
     Each rib  62  creates a partial flow obstruction of parts  24  moving along pile material  55  toward belt conveyor  20 . This flow obstruction results in an accumulation of parts  24  just upstream of each rib  62  which causes parts  24  to further spread widthwise across pile material  55 . It should also be noted that the flow obstructions created by rib  62  provide a means to control the flow of parts  24  through vibratory conveyor  18  regardless of part size. Preferably, the height of each rib  62  and the vibration amplitude imparted to planar member  54  are chosen in a way that will cause the greatest flow obstruction at the first rib  62 , a lesser flow obstruction at the second rib  62 , and so on such that, with each successive rib, the flow obstruction lessens. Thus, if the vibration amplitude is consistent across planar member  54 , the height of the first rib  62  would be the greatest with each subsequent rib  62  decreasing in height. It should be understood that the more vertically oriented vibration direction maximizes the effectiveness of ribs  62 . The spacing between adjacent ribs  62  should be chosen based on the expected average accumulation of parts  24  at each rib  62 . This can, of course, be determined empirically. The parts  24  will separate from one another thereby minimizing the amount of parts  24  overlapping one another. Overlapping parts  24  are not “pickable” and will therefore be recirculated. By helping to spread out parts  24  across the width of vibratory conveyor  18 , ribs  62  create a more uniform distribution of separated parts  24 . This results in an increase in the rate of flow of “pickable” parts  24 . This is illustrated in FIG. 6 which is a top plan view schematic showing part distribution density through the conveyance loop of apparatus  10 . Note that there is shown parts  24  gathering at each successive rib  62 . This gathering is what causes spreading of parts  24  across the width of vibratory conveyor  18 . With each successive rib  62  getting shorter, the “gathering” of parts  24  decreases ultimately leading to the desired more uniform density of parts  24  on the last section of vibratory conveyor  18  just before transfer to the belt conveyor  20 . It will be appreciated that for a given series of ribs  62 , the vibration amplitude of the planar member  54  may be adjusted to better achieve the desired average accumulation of parts  24  at each rib  62 . A larger vibration amplitude results in a overall decrease in average accumulation of parts at each rib  62  and a smaller vibration amplitude results in an overall increase in average accumulation of parts in at each rib  62 . 
     At the exit of the vibratory conveyor  18 , parts  24  are moved across a transition plate  80  and onto belt conveyor  20  due to the vibrations caused by electromagnetic actuator  72 . Transition plate  80  preferably has a minimal elevation change such that its length in the direction of flow is as short as possible and its angle of incline from transition plate  80  down to belt conveyor  20  is not more than about 5°. The short length and minimal elevation change of transition plate  80  allows parts  24  to be transferred without significantly affecting individual part orientation and separation. The velocity of bell conveyor  20  should be greater than or equal to the average speed of parts  24  traveling on vibratory conveyor  18 . Belt conveyor  20  is preferably traveling at a relatively slow velocity such as about one inch per second (1″/sec) for the purpose of inspection and picking. The speed of belt conveyor  20  may, of course be increased to thereby further increase flow rate of parts  24 . However, operating belt conveyor  20  at higher speeds will likely require a more expensive strobe lighting system for viewing parts  24  with the image capture means (not shown). Preferably, conveyor belt  20  is driven at a constant speed by a motor (not shown) and not in an indexing motion. If any starting and stopping of conveyor belt  20  is required, it should be done in such a manner that does not create any undesirable instability of parts  24  resting on belt conveyor  20 . Those skilled in the art will recognize that belt conveyor  20  will also have associated therewith an encoder (not shown) which allows monitoring of incremental belt movement. 
     Looking next at FIG. 7, there is shown a top plan view of the belt conveyor section  20 . Dotted line  82  represents the inspection field of view of the camera or other image capture means (not shown). Dotted line  84  represents the pick area from which the robot (not shown) picks parts  24  traveling on conveyor  20 . The inspection camera (not shown) is preferably directed perpendicular to the belt conveyor  20 . Examples of lighting and image capture systems which are particularly useful in combination with the present invention are disclosed in U.S. patent application Ser. No. 08/991,491 entitled, “Inspection Method and Apparatus for Determining the Side-up Orientation of an Object Resting on a Flat Surface” and U.S. patent application Ser. No. 08/991,728 entitled, “Method and Apparatus for Determining Orientation of Parts Resting on a Flat Surface” both filed on Dec. 16, 1997, which are hereby incorporated herein by reference. The combination of vibratory conveyor  18 , transition plate  80  and belt conveyor  24  provide an advantage in delivering separated parts  24  to an inspection field of view  82  in stable orientations. This advantage is significantly enhanced with the incorporation of ribs  62  into the vibratory conveyor  18 . 
     Parts  24  pass into the field of view  82  for inspection. Location information of all parts determined to be “pickable” is sent to the robot controller. The encoder allows for monitoring of all belt and part movement between the time of inspection and the time of grasping or picking. Parts  24  then pass into the pick area  84  where the robot grasps at least a portion of the parts  24  that have been inspected and determined to be “pickable”.  Any parts  24  which are not picked by the robot continue to move along belt conveyor  20  to fall into trough  22  and, as such, are returned to storage bin  12 . 
     Using the vibratory conveyor  18  of the present invention in combination with belt conveyor  20  enables separated parts  24  to be delivered to the field of view  82  far in excess of the conveyors of the prior art. Separated parts  24  can be delivered to the field of view  82  at rates ranging up to 60 to 100 parts per minute, or even higher. The automated process (whether it be inspection, robotic assembly, and/or part classification, etc.) in which the conveying system is being used is no longer limited by the rate at which usable parts are presented. Rather, the overall process becomes limited by the speed of the downstream activities. Thus, for example, if the separated parts  24  are being acquired from the pick area  84  for assembly, the speed of the assembly process will be limited by the speed of the robot and not by the rate at which separated parts  24  pass into the pick area  84 . 
     Due to the conveyance nature of the vibratory conveyor  18  and transition plate  80 , the majority of parts  24  passing into the inspection area or field of view  82  possess orientations which are relatively stable thereby minimizing the number of likely orientations for each individual part  24 . Minimizing the number of likely orientations increases the speed at which at which parts  24  can be inspected and/or identified for picking. If a less stable part orientation is desired for inspection and grasping by a robot, a change in elevation between transition plate  80  and belt conveyor  20  may be incorporated to intentionally and gently “tumble” parts  24  during transfer to belt conveyor  20 . 
     Those skilled in the art will recognize that overall part separations on belt conveyor  20  may, to some extent, be further increased without adversely affecting the uniformity of part distribution by two means. First, although not preferred, electromagnetic actuator  72  may be quickly cycled on and off to thereby operate vibratory conveyor  18  intermittently. By controlling electromagnetic actuator  72  in such a manner, a reduction in the overall rate at which parts  24  are transferred to belt conveyor  20  is achieved, thus, further increasing overall part separation on belt conveyor  20 . Alternatively, belt conveyor  20  can be driven at a higher constant speed. The higher speed of belt conveyor  20  will result in a greater separation of parts supported thereon as they are transferred from transition plate  80 . As stated above, those skilled in the art will appreciate that increasing the speed of conveyor belt  20  may require strobe lighting to obtain the sharp image of parts  24  necessary for inspection and/or picking. 
     From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth together with other advantages which are apparent and which are inherent to the invention. 
     It will be understood that certain features and subcombinations are of utility and may be employed with reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth and shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.