Abstract:
A loading system for the high speed loading of product in varying numbers comprising: an infeed conveyor having an infeed conveyor stop, a staging conveyor moving at a speed greater than the infeed conveyor and having a staging conveyor stop and a picking conveyor moving at or about the same speed as the staging conveyor and having a moveable picking conveyor stop. A photoelectric sensor or other similar counting device located in the region of the staging conveyor stop counts product as it moves from the infeed conveyor to the staging conveyor by counting the gaps between product units induced by the difference in the advancing speed of the infeed and the staging conveyors.

Description:
FIELD OF THE INVENTION 
   The present invention relates to systems for feeding product into robotic packaging or similar material handling systems and more particularly to such a system that utilizes a plurality of in-line conveyor systems incorporating intermittent stops that feed, count, separate and stage the product for picking, selection, etc. 
   BACKGROUND OF THE INVENTION 
   In the staging of product for picking by any of a wide variety of robotic devices, it is highly desirable to provide a mechanism that supplies the product to the robotic picking device in a timely and often in “bundles” or “layers” comprising varying numbers of individual product elements. Such a need exists, for example, in the packaging of bread or other similar bakery products. 
   In the prior art, such staging was often accomplished by manual separation means or otherwise using mechanical counters and the like. While such methods and the apparatus associated with them often proved entirely acceptable for relatively low speed applications they were often woefully inadequate for supplying product in groups or bundles of varying quantity to high speed loading devices such as picking robots. 
   There therefore exists a continuing need for a product feeding system capable of supplying product in varying numbers to a relatively high speed load robot or other device. 
   OBJECT OF THE INVENTION 
   It is therefore an object of the present invention to provide a high speed product feeding system that is capable of delivering product in varying numbers to a high speed loading or other device. 
   SUMMARY OF THE INVENTION 
   According to the present invention, there is provided a loading system for the high speed loading of product in varying numbers comprising: an infeed conveyor having an infeed conveyor stop, a staging conveyor moving at a speed greater than the infeed conveyor and having a staging conveyor stop and a picking conveyor moving at or about the same speed as the staging conveyor and having moveable picking conveyor stop. A photoelectric sensor or other similar counting device located in the region of the staging conveyor stop counts product as it moves from the infeed conveyor to the staging conveyor by counting the gaps between product units induced by the difference in the advancing speed of the infeed and the staging conveyors. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of a robotic material handling system incorporating the loading system of the present invention. 
       FIG. 2  is a partial schematic top plan view of the loading system of the present invention. 
       FIGS. 3-6  depict movement of product through the loading system of the present invention. 
   

   DETAILED DESCRIPTION 
   Referring now to the accompanying drawings the loading system of the present invention  50  comprises an infeed conveyor  52  having a servo controlled infeed conveyor stop  24 , a staging conveyor  54  having a servo controlled staging conveyor stop  28 , and a pick conveyor  56  having a laterally moveable pick conveyor stop  32  controlled by servo motor  33 . 
   In the view presented in  FIG. 2 , it can be seen that bread loaves  10  including attached tails  13  enter infeed conveyor  52  in the direction  36  indicated by arrow  38  and are arrested or stopped by infeed stop  24 . At the appropriate time as needed for loading, infeed stop  24  is drawn downward through the action of servo motor  26  allowing the appropriate number of loaves  10  that are counted by a photoelectric cell  27  or other mechanism located between infeed conveyor  52  and staging conveyor  54  to pass to staging conveyor  54  where they are stopped by staging conveyor stop  28  forming the next portion of product  10  to be advanced onto picking conveyor  56 . Loaves  10  are counted between infeed conveyor  52  and staging conveyor  54  through that action of photoelectric cell  27  that senses gaps induced between the loaves as they pass form infeed conveyor  52  to staging conveyor  54  due to the difference in speed between these two elements, i.e. loaves  10  on staging conveyor  54  are moving faster than those on infeed conveyor  54  thereby giving rise to gaps between the loaves as they advance from one conveyor to the other. At the appropriate time, i.e. when picking is required, staging conveyor stop  28  driven by servo motor  30  is retracted, in the embodiment depicted herein, downward and the bundle of loaves formed on staging conveyor  54  allowed to move forward to picking conveyor  56  where they are stopped by picking conveyor stop  32 . At this point, loaves  10  are ready for picking in any suitable fashion. In one possible scenario such picking would be by an end of arm tool or vacuum assisted picking device not shown. 
   Picking conveyor stop  32  driven by servo motor  35  is capable of lateral movement, i.e. in the direction indicated by arrow  33  so that product elements  10  that have been advanced onto picking conveyor  56  (in the Y direction) and need to be positioned for picking either: 1) proximate staging conveyor stop  28 ; or 2) intermediate staging conveyor stop  28  and the fully extended field of travel of picking conveyor stop  32  shown in  FIGS. 1 and 2  can be accommodated. Such a situation might occur in the case of a picking device having limited field of travel or in the instance where a rotating end effector is utilized and product  10  needs to be picked in a parallel but facing position that the rotating end effector can only access if product  10  is retained in some position other than that where it is stopped when picking conveyor stop  32  is in its fully traveled position as shown in  FIGS. 1 and 2 . 
   Referring now to  FIGS. 3-6  that schematically depict the operation of the material handling apparatus  50  of the present invention, as the system recognizes that there is product  10  to be packed system  50  starts. First the infeed conveyor stop  24  against which product  10  has been building on infeed conveyor  52  drops down and product  10  starts moving forward onto staging conveyor  54 . Since staging conveyor  54  is moving faster, it is pulling product  10  away from infeed conveyor  52  in such a way that a gap is created between the products  10  on infeed conveyor  52  and staging conveyor  54  as they pass infeed conveyor stop  24 . This gap is sensed with a photoelectric sensor  27  (see  FIGS. 1 and 2 ). Photoelectric sensor  27  can count the number of gaps it sees and when the proper number of product  10  have passed onto staging conveyor  54 , infeed conveyor stop  24  driven by servo motor  26  comes up in the gap between products  10  and stops the next product  10  from going onto staging conveyor  54 . Now, the number of products  10  required for the first pick is present on staging conveyor  54  and has accumulated up against the staging conveyor stop  28  (see  FIG. 3 ). Next, at the appropriate time, staging conveyor stop  28  drops down and passes the entire group of products  10  to pick conveyor  56 . There a third servo-adjustable backstop  32  on pick conveyor  56 , pick conveyor stop  32  which stops the first product in the group from going past that point. This is the point at which product  10  must be located for picking. As indicated by arrow  33  in  FIG. 1 , picking conveyor stop  32  can move in the Y direction as shown in  FIG. 5  to allow for picking in a position adjacent to staging conveyor stop  28 . In the example being presented here, a rotating end of arm tool (EOAT)  18  is waiting in the proper X, Z, and rotational position for the first pick. Rotating EOAT  18  comes down in the Z direction and picks products  10  from pick conveyor  56  using vacuum assisted suction cups  40  (see  FIG. 4 ). After the first group product  10  has started leaving staging conveyor  54 , the second group of product  10  to be picked can start entering staging conveyor  54  in the same fashion that the first product  10  group entered. The second group of product  10  is counted in the same way that the first group of product  10  was counted and released to staging conveyor  54 . Once this group of product  10  is on the staging conveyor (see  FIG. 3 ), held in the picking position by moveable picking conveyor stop  32  that has moved forward in the direction of arrow  33 , rotating EOAT  18  has picked the first group of product  10  and is up and out of the way, the second group of product  10  is ready for picking on picking conveyor  56 . After rotating EOAT  18  has picked the first group of product  10  it can immediately start rotating as indicated by arrow  19  and repositioning its X position to be ready for the next group of product  10  that has now been moved to picking conveyor  56  as just described. The servo controlled staging conveyor backstop  28  (Y-axis stop) can also immediately rise for its stopping position preparatory to building the next bundle to be picked. When the second group of product  10  is in the proper Y position on pick conveyor  56 , and once end effector  18  has adjusted to the proper W and X position for the second group of product  10 , rotating EOAT  18  is lowered in the Z direction such that it picks the second group of product  10  (see  FIG. 16 ). This process is repeated until the entire complex pattern of products (the layer or bundle) is assembled on rotating EOAT  18  as shown in  FIG. 6 . 
   While the operation of the various stops described hereinabove in connection with the accompanying drawings as being driven by servo motors, it will be readily understood by the skilled artisan that such devices could equally well be driven by pneumatic, hydraulic, electric or other suitable means, 
   There has thus been described a high speed loading system that is capable of moving counted quantities of product from an infeed station or location to a picking location.