Abstract:
A product conveying and accumulation system and method employs a primary product transporting conveyor with accumulation and re-circulating sections. The conveyor is configured to receive products from an upstream destination and discharge products to a downstream destination. A second conveyor, operable at a considerable slower speed than the first conveyor, is located in the same transverse plane as and is aligned adjacent to the first conveyor. Both conveyors travel in the same direction at the adjacent alignment. As products are discharged from the system, a wall of product is formed on the slower moving conveyor. As a result, products on the inner lane of the faster moving conveyor which would otherwise tend to move inward towards the discharge point, causing product turbulence and disruption, are urged back onto the inner lane by the product wall and then smoothly discharged from the system to the downstream destination. The use of this slower conveyor increases product stability by substantially eliminating product turbulence caused by the product bunching and nesting which normally occurs at the product discharge point. A substantially increased rate of product outfeed results.

Description:
BACKGROUND OF THE INVENTION 
   Product accumulation systems are routinely used in conjunction with conveyors for the storage and accumulation of products which are fed from upstream sources onto conveyors. In the normal operation of a typical system, products are placed on a conveyor at the upstream location, for instance at one operational station, and then transported to a downstream location by a conveyor where the next step in the manufacture or distribution of the products is to be accomplished. When there is a disruption at a downstream location which prevents the downstream destination from accepting products, system products which would normally be transported to the area of the disruption can be received and temporarily stored by an accumulator which is integral to the system. Examples of effective product conveyor and accumulation systems are disclosed in U.S. Pat. Nos. 6,575,287 and 6,959,802. 
   As products with particular configurations, e.g. elongated bottles, circulate around such conveyor/accumulation systems and other conveyor systems where some products are discharged downstream while others remain in the system, they are subject to product disruptions within the system. These disruptions especially occur just prior to product discharge downstream. Discharge disruptions primarily involve the bunching and nesting of products, which result in product instability and fallen and misaligned products. The outfeed rate and hence the efficiency of the system decreases and, when the disruption blocks the discharge, the entire system usually must be stopped to address the problem. 
   This situation is most prevalent as products reach and contact the discharge location or discharge point, usually the front end of the product discharge guide. Upon reaching this discharge point, products may begin to bunch and nest. As additional products enter the system from the upstream destination, they push the nested products which are ahead of them, causing product instability and exacerbating what may already be a clogged outfeed. 
   These problems are especially troublesome and are, in fact, exacerbated when the system is started up following a shutdown to address a downstream condition. Prior to such a shutdown, the system is routinely shifted, by a diverter gate-type element or similar means, from a product delivery mode to a product accumulating mode. As discussed in the above referenced patents, this allows for product accumulation while the downstream condition is being remedied. However, upon start-up, when the gate is opened and the system is returned to its product delivery mode, the immediate rapid influx of products at the discharge location results in increased nesting, bunching, and product turbulence, which, once again, creates the real threat of disruption of product flow. 
   While the systems in the U.S. Pat. Nos. 6,575,287 and 6,959,802 evidence significant, novel and effective systems in the conveying and accumulation of products, the systems disclosed and discussed therein do not specifically address the above stated problems of product instability at outfeed locations, under varying operating conditions. 
   SUMMARY OF THE INVENTION 
   It is thus an object of the present invention to overcome the disadvantages and limitations of prior product conveying and accumulation systems. 
   It is an object of the present invention to provide a product conveying and accumulation system to control and improve product stability at the system&#39;s discharge and thus substantially eliminate the disruptions which result from this instability. 
   It is a further object of the present invention to provide a product conveying and accumulation system which obtains smoother product outfeed by substantially eliminating disruptions at discharge. 
   It is an object of the present invention to provide a product conveying and accumulation system which controls and improves product stability at the system&#39;s discharge upon immediate start-up of the system, following a shutdown to address a downstream condition. 
   It is another object of the present invention to provide a product conveying and accumulation system which employs the use of a separate conveyor section or lane which is stationary or a conveyor specifically operable at a slower speed than the primary product transporting conveyor or conveyors in order to improve product stability, substantially eliminate disruptions and obtain markedly smooth and increased product outfeed. 
   It is still another object of the present invention to provide a product conveying and accumulation system method which employs the use of a separate conveyor section or lane which is stationary or specifically operable at a slower speed than the primary product transporting conveyor or conveyors, in order to improve product stability, substantially eliminate disruption and obtain markedly smooth and increased product outfeed. 
   These and other objects are accomplished by the present invention, a product conveying and accumulation system and method which employs a primary product transporting conveyor with accumulation and re-circulating sections. The conveyor is configured to receive products from an upstream destination and discharge products to a downstream destination. A second conveyor, operable at a considerably slower speed than the first conveyor, is located in the same transverse plane as and is aligned adjacent to the first conveyor. Both conveyors travel in the same direction at the adjacent alignment. As products are discharged from the system, products are positioned on the slower moving conveyor. These products form a temporary wall of products on the slower moving conveyor. As a result, products on the inner discharging lane or lanes of the faster moving conveyor which would otherwise tend to move inward towards the discharge point, causing product turbulence and disruption, are urged back outward onto the inner lane or lanes by the product wall. This allows for increased separation between the discharging products and the discharge point, permitting the products to be smoothly discharged from the system to the downstream destination. A substantially increased rate of product outfeed results. The use of this slower conveyor increases product stability by substantially eliminating product turbulence caused by the bunching and nesting of products which normally occurs at the product discharge point, both during normal operation and upon start-up of the system following a shutdown. An alternate system employs the use of a stationary conveyor section or lane, in lieu of a slower moving conveyor. 
   Novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention, itself, however, both as to its design, construction and use, together with the additional features and advantages thereof, are best understood upon review of the following detailed description with reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a top view of a prior art product conveying and accumulation system. 
       FIG. 2  is a top view of a product conveying and accumulation system employing the present invention. 
       FIG. 3  is an isolated view of the product conveying and accumulation system taken from  FIG. 2 . 
       FIG. 4  is an isometric view of the product conveying and accumulation system shown in  FIG. 2 . 
       FIG. 5  is a top view of another product conveying and accumulation system showing another system arrangement employing the present invention. 
       FIG. 6  is a top view of the product conveying and accumulation system of the present invention, showing a two lane product discharge, isolated at the discharge with a product diverter gate retracted. 
       FIG. 7  is a top view showing the area in  FIG. 6 , with the diverter gate extended. 
       FIG. 8  is a top view showing the area in  FIG. 7 , depicting the flow of discharging product once the diverter gate is again retracted. 
       FIG. 9  is a top view of the product conveying and accumulation system showing another embodiment of the present invention. 
       FIG. 10  is an isolated view of the product conveying and accumulation system taken from  FIG. 9 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  is representative of a prior, popular conveying and accumulation systems. Products  100 , for example bottles, are typically transported from upstream destinations  2  and  3  to conveyor system  4  which ultimately moves the products to downstream destinations  6  and  7 . Accumulator section  8  is designed to accept and accumulate products which cannot yet be positioned for downstream transport. Such products are re-circulated via re-circulating section  10  for ultimate delivery to downstream destinations  6  and  7 . Particular reference is made to U.S. Pat. No. 6,575,287, which describes this novel system in detail. 
   However, such prior systems, while most effective in transporting and accumulating products, do not address certain difficulties which arise during the movement of particular products, like elongated bottles, which, as they approach discharge locations or discharge points  12  and  16  of guide members  14  and  18 , tend to bunch-up or nest at the discharge locations. This causes a crowding of products and turbulence at the discharge locations and results in a decrease in downstream outfeed delivery of products, overturned products  20  and loss of efficient downstream transport of products, and a general disruption of the smooth delivery of products downstream. 
     FIGS. 2-4 , show a system employing the present invention which alleviates these product delivery disruption problems. Products  200 , delivered from upstream destination  22 , are transported onto conveyor  24 , having a plurality of outer product path lanes  26 , inner product path lane  28  and accumulator section  30 . Products are ultimately delivered to downstream destination  34 . Conveyor  24 , driven by motor or similar power means  36 , is operated at a constant product delivery speed in, for example, the clockwise direction shown in  FIGS. 2-4 . 
   In accordance with the present invention, second conveyor  40  is a single, continuous looped path conveyor located in a single vertical plane, aligned adjacent to inner lane  28  of conveyor  24 , preferably in the same transverse plane as the inner lane. Conveyor  40  is positioned intermediate between lane  28  and accumulation section  30 . Motor or similar power means  42  drives conveyor  40  in the same direction as conveyor  24 , at inner lane  28 , i.e. at the adjacent alignment between conveyor  40  and inner lane  28 , but at a considerably slower speed than conveyor  24  and its inner lane. The particular characteristics of the products being transported and the configuration of the system will dictate the difference in speed between slower moving conveyor  40  and conveyor  24  and this speed differential is not to be considered as a restrictive of the scope of the invention. 
   Product guide  48  has extension  47  which terminates at discharge point or location  44 . Discharge location  44  is positioned between inner path lane  28  and conveyor  40 . 
   Operation of conveyor systems in accordance with the present invention addresses the problems and disruptions resulting from the bunching and nesting of products at the discharge location. As products  200  move from upstream destination  22  towards discharge location  44 , they are compelled by inboard surfaces  45  of guide  46  towards inner path lane  28  and slower moving conveyor  40 . Products  200  which remain positioned on lane  28  are delivered to downstream destination  34  through guide channel  50 . Products  200   a  are pushed onto conveyor  40  and continue to move in the direction of conveyor  24 , but since conveyor  40  is traveling at a slower speed than conveyor  24 , products  200   a  on that conveyor also travel at that slow speed. A number of products  200   b  are pushed off conveyor  40  onto accumulator section  30 , which recycles those products for eventual discharge to downstream destination  34 . 
   Products  200   a , traveling slowly in relation to the speed of conveyor  24 , will tend to form a temporary, artificial “wall”  201  of products  200   a  on conveyor  40 . Products  200  on fast moving inner lane  28  which would otherwise tend to move inward towards discharge location  44 , causing bunching and nesting and the resulting turbulence, are urged back outward and realigned onto inner lane  28 , towards inboard surfaces  45  of guide  46 , by products  200   a  forming product wall  201 . This allows for increased separation, at  49 , between discharging products  200  and discharge location  44 . This separation virtually eliminates contact between products  200  and discharge location  44 , thus eliminating product nesting and the turbulence which results. Surface  51  of guide  46  is specifically indented in order to allow increased inward movement of products  200  as they are discharged from the system, to provide for additional separation  49  between products and discharge location  44 . 
   The virtual elimination of turbulence at discharge location  44  results in tremendously enhanced product stability, achieving a substantially increased rate of smooth product outfeed. 
     FIG. 5  shows a second arrangement of the invention employed with another conveyor/accumulation system, a system with dual product feed and product outfeed. Products  200 , delivered from upstream destinations  70  and  88  are transported onto conveyor  64 , having outer product discharge path lanes  76  and  92  and inner product discharge path lanes  77  and  91 , and accumulator sections  66  and  67 . Conveyor  64  is operated at a constant product delivery speed in, for example, the clockwise direction shown in  FIG. 5 . Products are directed and discharged to downstream destinations  72  and  90 , by guides  80  and  82 , and  95  and  96 , via guide channels  84  and  94 . Guides  80  and  96  have indented sections at  81  and  93  respectively. 
   In this embodiment, second conveyor  60  is a continuous single continuous looped path conveyor with two lower wrap-around sections. Conveyor  60  has four upper product path lanes moving in a single transverse plane, including path lanes  61  and  63 , which are aligned adjacent to inner lanes  77  and  91  of conveyor  64 , preferably in the same transverse plane as these inner lanes. Motor or similar power means  62  drives conveyor  60  and path lanes  61  and  63  in the same direction as conveyor  64 , at inner lanes  77  and  91 , i.e. the adjacent alignment between conveyor  60  and inner lanes  77  and  91 , but at a slower speed than conveyor  64  and its inner lanes  77  and  91 . As in the initially discussed embodiment, particular characteristics of the products being transported and the configuration of the system dictate the difference in speed between conveyor  60  and conveyor  64 . 
   Similar to the operation described previously, as products  200  move from upstream destinations  70  and  88 , towards discharge locations points  78  and  98 , they are compelled by inboard surfaces  101  and  102  of guides  80  and  96  towards inner lanes  77  and  91 . Products  200  which remain positioned on outer path lanes  76  and  92  are delivered to downstream destinations  72  and  90 , through guide channels  84  and  94 . Products  200   a  are pushed onto path lanes  61  and  63  of conveyor  60  and continue to move in the direction of conveyor  64 , but since conveyor  60  is traveling at a slower speed, products  200   a  on the path lanes of that conveyor also travel at the slower speed. A number of products  200   b  are pushed off conveyor  60  onto accumulator sections  66  and  67 , which recycles those products for eventual discharge to downstream destinations  72  and  90 . 
   Products  200   a , traveling very slowly in relation to the speed of conveyor  64 , form temporary, artificial walls of products, as described previously in regard to the embodiment of  FIGS. 2-4 , as products  200  and  200   a  approach discharge locations  78  and  98 . Products  200  on faster moving inner lanes  77  and  91  which would otherwise tend to move inward towards discharge locations  78  and  98 , causing bunching and nesting and the resulting turbulence, are urged back outward and realigned onto inner lanes  77  and  91 , and outer lanes  76  and  92 , towards inboard surfaces  101  and  102  of guides  80  and  96 , by products  200   a  forming the temporary product walls. This allows for increased separation at  79  and  99 , between discharging products  200  and discharge locations  78  and  98 . This separation virtually eliminates contact between products  200  and discharge locations  78  and  98 , thus eliminating product nesting and the turbulence which results. Surfaces  81  and  93  of guides  80  and  96  are specifically indented in order to allow increased inward movement of products  200  as they are discharged from the system, to provide for additional separation  79  and  99  between products and discharge locations  78  and  98 . Product stabilizing improvement at these discharge points, also previously described, again results in a smoother and increased outfeed of products to the downstream destinations; since the walls of products on the slow lanes inhibit the faster moving outfeed products from interacting with the discharge locations, creating separation between product and discharge locations. 
   Although the use of a slow lane product conveyor is shown employed with two specific product conveying and accumulation systems, the present invention should not be considered restricted to these two systems. The slow lane product conveyor is adaptable to any system which employs a primary product transport conveyor and where there is a desire to eliminate product turbulence at the point of discharge. 
   The bunching and nesting of products at discharge locations is especially problematic when a conveying system is started up following a shutdown to address a downstream condition. Prior to a shutdown, while normal product delivery operations are underway, the system will normally be shifted, by a diverter gate-type connection or similar means, from a product delivery mode to a product accumulation mode. As discussed in U.S. Pat. Nos. 6,575,287 and 6,959,802, this allows for product accumulation while the downstream condition is being remedied. However, upon start-up, when the system is returned to its product delivery mode, the immediate rapid influx of products at the discharge location results in increased nesting, bunching, and product turbulence, which creates a real problem of disruption of product flow.  FIGS. 6-8  show how the present invention is particularly effective in addressing these system shut-down to start-up situations. 
   Referencing the system shown in  FIG. 5 , but isolating on the vicinity of discharge location  78 ,  FIG. 6  shows the system in the product delivery mode, with path lanes  76  and  77  of conveyor  64  operating at a constant speed and path lane  61  of conveyor  60  operating at a slower speed. As previously discussed, products  200   a  on lane  61 , forming temporary wall  201 , serve to compel products  200  on paths  76  and  77  towards surface  101  and indented section  81  of guide  80 . This creates separation, at  79 , ahead of discharge location  78  at the end of extension  83  of guide  82 , to eliminate product discharge turbulence. 
   However, when there is a disruption which must be addressed downstream and the flow of delivered products must temporarily be stopped, a gate connection, such as pivoted gate  100  shown in  FIGS. 6-8 , is pivoted down and extended across product delivery lanes  76  and  77  and past slow path lane  61 . See  FIG. 7 . This causes products in all lanes to be shifted to accumulator section  66 , which accumulates the products while the downstream condition is being addressed. 
   When the downstream condition has been remedied and product delivery is to start, gate  100  is pivoted back and retracted to once again open all lanes. If the differential speed conveyor system of the present invention is not employed, as gate  100  is pivoted back, products  200 , all traveling at the same high speed, will approach discharge location  78  at this high speed. This results in the bunching, nesting and turbulence, which the invention solves.  FIG. 8  shows the movement of products after gate  100  is pivoted back, when slower conveyor  60  is employed. Products  200   a  on slow lane  61  immediately form temporary wall  201 , which compels products  200  toward surface  101  and indented section  81  and away from discharge location  78 . Separation is created, at  79 , between products  200  and discharge location  78 , thus eliminating the ever-present product turbulence problems resulting from system start-up. 
   The concepts of differential speed conveyors of the present invention, will successfully work when the lane is operating at any slower speed in relation to the product delivery conveyors. However,  FIGS. 9 and 10 , another embodiment of the invention, evidences that the system will also work effectively if the slower lane is replaced by a stationary lane. In the system shown in  FIGS. 9 and 10 , products  200  delivered from upstream destination  122 , are transported onto conveyor  124 , having a plurality of outer product path lanes  126 , inner product path lane  128  and accumulator section  130 . Products are ultimately delivered to downstream destination  134 . Conveyor  124 , driven by motor or similar power means  136 , is operated at a constant product delivery speed in, for example, the clockwise direction shown in  FIGS. 9 and 10 . 
   In accordance with this embodiment of the invention, a stationary lane or stationary conveyor section  140 , is aligned adjacent to inner lane  128  of conveyor  124 , and intermediate of lane  128  and accumulation section  130  and preferably in the same transverse plane as the inner lane and accumulator. Product guide  148  has extension  147  which terminates at discharge point or location  144 . Discharge location  144  is positioned between inner path lane  128  and stationary lane  140 . 
   Operation of this embodiment is similar to that which has been described previously, with regard to the slow lane systems. As products  200  move from upstream destination  122  towards discharge location  144 , they are compelled by inboard surfaces  145  of guide  146  towards inner path lane  128  and stationary lane  140 . Products  200  which remain positioned on lane  128  are delivered to downstream destination  134  through guide channel  150 . Products  200   a  are pushed onto stationary lane  140  and continue to move in the direction of conveyor  124 , but since lane  140  is stationary, products  200   a  on the lane also remain substantially static or stationary. Several products  200   b  on lane  140  will be slightly nudged off the lane by products  200  traveling on lane  128  and they will eventually be shifted onto accumulator section  130 . However, most of the static positioned products  200   a  will form a temporary wall  202 , which, as described previously, act to compel products  200  back outward towards inboard surface  145  and indented section  151  of guide  146 . The ensuing separation between products  200  and discharge location  144 , at  149 , once again, eliminates the product turbulence. 
   Certain novel features and components of this invention are disclosed in detail in order to make the invention clear in at least one form thereof. However, it is to be clearly understood that the invention as disclosed is not necessarily limited to the exact form and details as disclosed, since it is apparent that various modifications and changes may be made without departing from the spirit of the invention.