Patent Publication Number: US-6220330-B1

Title: Conveyor system incorporating article guide and positioning arrangement for a labeling station

Description:
BACKGROUND OF THE INVENTION 
     Conveying systems are often employed to convey articles through a series of sequential working stations. In certain conveyor systems, a number of different articles are separately stacked in a series of individual dispensers mounted along a moving conveyor. Through operation of a computer program, individual articles are selectively dispensed onto the moving conveyor, and the articles are then conveyed to a location where they can be stacked and packaged for shipment to the customer. 
     Typically, the articles are generally rectangular and include a pair of relatively wide flat face surfaces and an outer peripheral edge defined by relatively narrow individual side surfaces. The articles are fed by the dispensers onto the conveyor such that one of the face surfaces contacts the conveyor. Downstream from the dispensers, the individual articles are reoriented onto one of their side surfaces and are conveyed through the remaining portion of the conveying system while resting on the side surface. In many conveying systems, a labeling station is positioned downstream from the dispensers such that labels can be applied to the articles before the articles are assembled into stacks. Typically, the labeling station includes at least one labeling unit that applies a label to the article without actually contacting the article. 
     In past labeling stations included in conveying systems of this type, the article is supported on a conveyor belt as it passes through the labeling station. A pair of stationary guide members are spaced above the conveyor belt to prevent the article from tipping back onto its face surface as the article is conveyed through the labeling station. Typically, these guide members are spaced a predetermined distance greater than the maximum width of the articles being handled by the system, such that articles of different sizes are able to travel through the labeling station. 
     Since the article is not positively supported as a label is applied, problems exist in using the labeling station to apply labels to articles having different sizes. For example, a VCR tape is much wider than a compact disc container, such that the position of the article with respect to the labeling unit may vary depending on the type of article. This creates difficulties in controlling label application to provide consistent label placement and positive engagement of the label with the surface of article. Therefore, a need exists to provide a labeling station that increases control of the interface between the article and the label applicator as the article passes through the labeling station. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an apparatus for supporting and applying labels to individual articles as the articles are moved in a single-file fashion along a primary conveyor assembly. The plurality of articles, such as video cassette containers, compact disc containers, audio cassette containers, or the like are conveyed in an upright, singulated fashion on a primary conveyor belt which transports the articles through a labeling station. A biasing assembly contained in the labeling station contacts each of the individual articles and forces the article into contact with a stationary guide assembly. The biasing assembly is operated at substantially the same speed as the primary conveyor assembly, such that the article is continuously pressed against the stationary guide assembly as the article moves through the labeling station. A plurality of labeling units are positioned to apply a label to each article as the article is supported against the stationary guide assembly by the biasing assembly. The stationary guide assembly defines an article engagement with the article engagement surface spaced a predetermined distance from each of the labeling units, and the biasing assembly maintains each article in engagement surface as the articles are transported past the labeling units. In this manner, each of the plurality of articles is supported in an identical position relative to the labeling unit. 
     The biasing assembly of the invention includes a biasing belt that is operated at the same speed as, or at a faster speed than, the primary conveyor belt. The biasing belt is entrained between an upstream roller and a downstream roller and rotates thereabout. The biasing belt includes a continuous backing belt and a plurality of loops extending from the backing belt. The plurality of loops are formed from a continuous strip of material. The continuous strip of material is fixed to the backing belt at a plurality of trough portions each located between adjacent loops. In this manner, the continuous strip of material forms the loops that extend from the backing belt. 
     The primary conveyor belt supports each of the articles on its side, and moves the articles through the labeling station. The biasing belt is positioned above the primary conveyor belt such that the loops of the biasing belt are spaced slightly inward from the article engagement surface of the stationary guide assembly. Preferably, the distance between the plurality of loops and the article engagement surface is less than the thickness of the thinnest article being handled by the system. 
     As the biasing belt contacts one of the articles, the individual loops in contact with the article flex inward to deform the original shape of the loop. The flexible loops exert a relatively soft lateral force on the article to press the article toward the article engagement surface of the stationary guide assembly. 
     The stationary guide assembly preferably includes an upper guide rail and a lower guide rail which are positioned adjacent to the lateral edge of the primary conveyor belt. The upper and lower guide rails are positioned above the primary conveyor belt, and each guide rail defines an article engagement surface generally aligned with the lateral edge of the primary conveyor belt. The flexible loops of the biasing belt exert a force on a second face surface of the article to force a first face surface of the article into contact with the article engagement surfaces of the upper and lower guide rails. Since the biasing belt and the primary conveyor belt are operated at substantially the same speed, the individual loops of the primary conveyor belt continuously force the article into contact with the article engagement surfaces of the upper and lower guide rails as the articles are transported past the labeling units. 
     As each article passes through the labeling station, the article is continuously pressed against the upper and lower guide rails by the biasing belt. When the article is pressed against the article engagement surfaces of the upper and lower guide rails, the first face surface of the article is always positioned a known distance from the label application of each labeling unit contained within the labeling station, regardless of the thickness of the article. In this manner, the labeling units can accurately and consistently apply a label to each article as it passes through the labeling station. 
     Therefore, it is an object of the invention to provide a mechanism for applying labels to articles being moved in a single-file fashion along a primary conveyor assembly. It is an additional object of the invention to provide a biasing assembly to exert a force to hold each individual article moving along the primary conveyor assembly in contact with a stationary guide assembly. It is another object of the invention to provide a biasing assembly that positions the article in a known relationship to a labeling unit contained in the labeling station. It is a further object of the invention to provide a biasing belt in the biasing assembly that flexes laterally upon engagement with an article to exert an outward force to hold the article in contact with the stationary guide assembly. It is a further object of the invention to provide a biasing assembly that operates at substantially the same speed as the primary conveyor assembly such that the biasing assembly supports the article as the article moves through the labeling station. 
    
    
     Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The drawings illustrate the best mode presently contemplated of carrying out the invention. 
     In the drawings: 
     FIG. 1 is a top plan view of an article sorting and conveying system incorporating the label printing and applicating mechanism of the present invention; 
     FIG. 2 is an enlarged top plan view of the label printing and applicating mechanism of the present invention as incorporated into the article sorting and conveying system of FIG. 1; 
     FIG. 3 is a sectional view taken along line  3 — 3  of FIG. 2 showing a labeling unit and a biasing assembly of the present invention; 
     FIG. 4 is a partial sectional view taken along line  4 — 4  of FIG. 3 showing a biasing belt of the biasing assembly and a stationary guide assembly; 
     FIG. 5 is a partial top plan view with reference to line  5 — 5  of FIG. 4, showing the interaction of the biasing belt and an article to which a label is applied; and 
     FIG. 6 is a sectional view taken along line  6 — 6  of FIG.  5 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates an article sorting and conveying system  10  that dispenses separately stacked articles and conveys the articles to a location where they can be packaged for shipment. The article sorting and conveying system  10  generally includes a dispensing section  12  that includes a series of dispensers  14  that dispense articles onto an infeed conveyor  16 . The dispensing section  12  can include a number of dispensers  14 , each of which may contain a different type of article, such as video tapes, compact discs, audio cassettes and the like, or a series of different articles of the same type. The detailed construction of each individual dispenser  14  is shown and described in the commonly owned U.S. Pat. No. 5,586,685, incorporated herein by reference. 
     The articles are individually dispensed onto the infeed conveyor  16  such that the flat face surface of the article rests upon the infeed conveyor  16 . Once dispensed onto the infeed conveyor  16 , the articles are moved downstream to a reorientation section  18  where the individual articles are repositioned onto one of their side surfaces. Each of the articles is then transported throughout the remainder of the article sorting and conveying system  10  supported on its side surface. 
     After each article has passed through the reorientation section  18 , the article continues to move downstream and passes through a bar code reader  20  that is able to accurately and quickly identify the article being moved by the article sorting and conveying machine  10 . A computer operating station  22  allows an operator to control and monitor the operation of the article sorting and conveying system  10 . 
     Once the individual article has been identified by the bar code reader  20 , the article enters a labeling station  24  that can apply various types of labels or stickers to the article moving through the article sorting and conveying system  10 . In the embodiment of the invention shown in FIG. 1, the labeling station  24  includes a series of individual labeling units  26  that operate independently to apply a label to each article passing through the labeling station  24 . 
     After leaving the labeling station  24 , each individual article is diverted into one of a series of stacker mechanisms  27  depending on the type of article required to form the stack being assembled by each individual stacker mechanism  27 . The series of stacker mechanisms  27  allow several individual stacks to be assembled simultaneously. Each of the stacker mechanisms  27  assembles a stack of articles, each of which is resting on its side surface. If none of the stacker mechanisms  27  require the individual article passing along the article sorting and conveying system  10 , the article is collected in a storage container  29  positioned at the downstream end of the article sorting and conveying machine  10 . In this manner, the article sorting and conveying system  10  is able to simultaneously assemble stacks of different types of articles, and stacks of different articles of the same type, where the articles are intermingled in a continuous, single-file stream. Thus, the article sorting and conveying system  10  significantly increases the flexibility of the stacking operation, since the article sorting and conveying system  10  does not need to be separately configured for each type of article being stacked. 
     FIG. 2 illustrates the labeling station  24  of the article sorting and conveying system  10 . The labeling station  24  receives an article  28  that is traveling along a primary conveyor assembly  30  that includes a primary conveyor belt  32  and a pair of spaced guide members  34  and  36 . The guide members  34  and  36  are spaced above the conveyor belt  32  such that the guide members  34  and  36  loosely retain the article  28  to prevent the article  28  from tipping back onto its face surface while the side surface of the article  28  is supported on the conveyor belt  32 . Specifically, the guide members  34  and  36  are spaced from each other by a distance sufficient to accommodate articles having different sizes, such as VCR tape containers and compact disc containers. 
     The labeling station  24  includes a series of labeling units  26  that are sequentially aligned along one edge of the conveyor belt  32 . As can be seen in FIG. 3, the labeling units  26  are positioned adjacent to a lateral edge  38  of the primary conveyor belt  32 , such that each labeling unit  26  can apply a label to an article  28  supported on the primary conveyor belt  32 . Representatively, the labeling unit  26  is a conventional labeling unit such as is sold by Label-Aire, Inc. of Fullerton, Calif., under Model No. 2138. 
     Each labeling unit  26  includes a roll  40  of self-adhesive, blank labels. The roll of labels  40  is fed around a pair of rollers  42  and into a printing assembly  44 . The printing assembly  44  prints preselected information onto the individual labels. For example, the predetermined information printed by the printing assembly  44  could be the retail price of the article, a tracking or distribution code, or any other information which may vary depending upon the order or retail establishment for which the article  28  is destined. Repersentatively, the printing assembly  44  is a commercially available print engine available from SATO under Model No. 8485S. 
     After passing through the printing assembly  44 , the label is removed from its backing by a suction device contained on a print head  46 . After the label has been removed from the backing, the suction device is moved into a position near the article  28 , as shown in FIG.  4 . Once near the article  28 , the air flow direction in the print head  46  is reversed, such that the supply of air forces the label into contact with the article  28 . In this manner, a label can be applied to the article  28  without the print head  46  ever contacting the article  28 . 
     After the label has been removed from the backing, the backing is wound around a wind-up roller  48 . In this manner, the roll of labels  40  is printed, applied and disposed of by the labeling unit  26 . 
     As shown in FIG. 2, a series of labeling units  26  are included in the labeling station  24 . In prior systems, it was found that the primary conveyor assembly  30  could be operated at a speed faster than the speed a single labeling unit  26  could print and apply a label to each one of the articles. Thus, in a system having only a single labeling unit  26 , a bottleneck was created in the article sorting and conveying machine  10  at the labeling unit  26 . To eliminate the bottleneck, the series of labeling units  26  are positioned sequentially within the labeling station  24 , which allows the primary conveyor assembly  30  to be operated at an optimal speed without causing a bottleneck in the labeling station  24 . Each of the labeling units  26  operates in an identical manner and the labeling units  26  can be configured either to print identical or different labels, depending upon the system requirements. 
     As the article  28  enters into the labeling station  24  on the primary conveyor belt  32 , the article  28  contacts a biasing assembly  48 . The biasing assembly  48 , as shown in FIG. 2, includes a biasing belt  50  that is entrained between an upstream roller  52  and a downstream roller  54 . Both the upstream roller  52  and the downstream roller  54  are disposed to rotate about a generally vertical axis. The downstream roller  54  is driven by a motor  56 , such that the downstream roller  54  acts as a drive roller to rotate the biasing belt  50  between the upstream roller  52  and the downstream roller  54 . In the preferred embodiment of the invention, the motor  56  drives the biasing belt  50  at the same speed as, or at a speed slightly faster than, the speed of the primary conveyor belt  32 . 
     The biasing belt  50  includes a series of loops  58  positioned along the entire length of the biasing belt  50 , as shown in FIG.  2 . As can best be seen in FIG. 5, each of the loops  58  is formed from a continuous length of material  59  that is fixed to a backing belt  60  at regular intervals to define the plurality of loops  58 . In this manner, the backing belt  60  and the continuous length of material  59  forming the loops  58  combine to form the biasing belt  50 . 
     Each of the loops  58  includes an arcuate outer contact surface  62  that is spaced from the lateral edge  38  of the primary conveyor belt  32  when the loop  58  is in a relaxed state and not in contact with an article  28 . In the preferred embodiment of the invention, the distance between the arcuate outer contact surface  62  of each loop  58  and the lateral edge  38  of the primary conveyor belt  32  is based on the width of the thinnest of the articles  28  to be handled by system  10 , for reasons that will be discussed in greater detail below. 
     As can be seen in FIG. 5, the continuous length of material  59  that forms the series of loops  58  includes trough portions  66  that are each fixed to the backing belt  60 . The fixed trough portions  66  allow the continuous length of material  59  to retain the desired shape to define the series of loops  58 . In the preferred embodiment of the invention, each of the trough portions  66  is fixed to the backing belt  60  by a commercially available adhesive, although other attachment means, such as stitching or the like, may be utilized. Additionally, it is contemplated that the loops  58  could be formed from separated pieces of material fixed at each end to the backing belt  60 . 
     Referring now to FIG. 4, the biasing assembly  48  is mounted to a frame  68  for the labeling station  24  by a series of mounting brackets  70 . The mounting brackets  70  are positioned at a slight angle relative to vertical such that the biasing belt  50  is positioned at a slight angle relative to the generally horizontal primary conveyor belt  32 . An upper support assembly  72  and a lower support assembly  74  extend along the length of the biasing assembly  48  to support the biasing belt  50  and maintain the operative run of biasing belt  50  in position above the primary conveyor belt  32 , as shown in FIG.  4 . The lower support assembly  74  is attached to the mounting brackets  70  by conventional connectors  76 . 
     As can be seen in FIG. 4, the primary conveyor belt  32  is supported above the frame  68  by a pair of side supports  78  and  80 . The side supports  78  and  80 , in turn, are mounted to the frame  68  by a pair of mounting blocks  82  and  84 , respectively. 
     A stationary guide assembly  86 , including an upper guide rail  88  and a lower guide rail  90 , is positioned adjacent to and above the lateral edge  38  of the primary conveyor belt  32 . The stationary guide assembly  86  extends along the entire length of the labeling station  24  such that the stationary guide assembly  86  can support the article  28  as the article  28  moves through the labeling station  24 . 
     The stationary guide assembly  86  includes a series of vertical support brackets  92  spaced along the length of the labeling station  24  to support the upper guide rail  88  and the lower guide rail  90 . Each of the support brackets  92  is mounted to the side support  78  by a mounting block  94  and a conventional connector  96 . The mounting block  94  provides the required spacing between the support bracket  92  and the lateral edge  38  of the conveyor belt  32 . 
     Each of the support brackets  92  extends vertically upward from the mounting block  94  such that both the upper guide rail  88  and the lower guide rail  90  define vertically aligned outwardly facing article surfaces, which are positioned above the top surface of primary conveyor belt  32 . As can be seen in FIG. 4, the upper guide rail  88  and the lower guide rail  90  define vertically aligned outwardly facing engagement surfaces which are positioned directly above the lateral edge  38  of the primary conveyor belt  32 , and which engage a first face surface  96  of the article  28  as the article  28  is moved through the labeling station  24  by the primary conveyor belt  32 . An extended portion  98  of the side support  78  extends above the primary conveyor belt  32  in alignment with the article engagement surfaces of guide rails  88 ,  90  such that the extended portion  98  maintains side surface  100  of the article  28  in a vertical position on the primary conveyor belt  32 . 
     Referring now to FIG. 6, the upper guide rail  88  is mounted to the support bracket  92  by a mounting block  102 . The mounting block  102  includes an internal passage  104  extending throughout its length. A nut  106  is received within passage  104 , and engages the threaded shank of a connector  108 , which extends through aligned openings in bracket  92  and the wall of mounting block  102  adjacent there to, for securing mounting block  102  to bracket  92 . Mounting block  102  includes T-shaped section  110  which is received in a corresponding groove formed in the upper guide rail  88 . In the preferred embodiment of the invention, the upper guide rail  88  is formed from a low friction material, such as extruded nylon. Although the mounting arrangement for only the upper guide rail  88  has been discussed in FIG. 6, an identical mounting arrangement is also utilized between bracket  92  and lower guide rail  90 . 
     In operation, labeling station  24  functions as follows to apply a label to an article  28  passing through labeling station  24 . As shown in FIG. 2, article  28  initially enters the labeling station  24  on primary conveyor belt  32 , moving in the direction shown by arrow  112 . As the article  28  is moved by the primary conveyor belt  32 , the article  28  comes into contact with the biasing belt  50  of the biasing assembly  48 . 
     As previously discussed and as shown in FIG. 5, the biasing belt  50  is positioned such that the arcuate outer contact surface  62  of each loop  58  is positioned a distance from the upper guide rail  88  and the lower guide rail  90  that is less than the thickness of article  28  between its first face surface  96  and its second face surface is shown at  114 . The distance between the biasing belt  50  and the guide rails  88  and  90  is selected based on the thinnest article  28  that will be processed, since the biasing belt  50  can flex to accommodate thicker articles  28 . 
     As the article  28  reaches the biasing belt  50 , several of the individual loops  58  of the biasing belt  50  contact the second face surface  114  of the article  28 , as shown in FIGS. 4 and 5. Since the thickness of the article  28  is greater than the distance between the arcuate outer contact surface  62  of each loop  58  and the guide rails  88  and  90 , the individual loops  58  in contact with the second face surface  114  of the article  28  flex inward as shown in FIG.  5 . As the loops  58  flex inward, the loops  58  exert a relatively soft lateral force on the article  28  to press the first face surface  96  of the article  28  into contact with upper guide rail  88 , lower guide rail  90 , and extended portion  98  of side support  78 . As shown in FIG. 4, the article  28  may only contact the lower guide rail  90  depending on the height of the article  28 . However, if a taller article  28  is passing through the labeling station  24 , the article  28  may also contact the upper guide rail  88 . In this manner, the labeling station  24  can accommodate articles  28  having a variety of heights. 
     Due to its slight downward angle, biasing belt  50  also functions to apply a slight vertically downward force on article  28 . This downward force maintains the bottom side surface  100  of article  28  in engagement with primary conveyor belt  32 , and also maintains the lower end of first face surface  96  in engagement with side support extended portion  98 . 
     Loops  58  are capable of deforming to varying degrees to accommodate articles  28  having varying thickness. In this manner, the collapsibility of loops  58  enables biasing belt  50  to exert a soft lateral biasing force on all articles  28  regardless of their thickness, to maintain articles  28  in engagement with guide rails  88 ,  90  and side support extended portion  98  during transport through labeling station  24 . 
     After reaching the biasing belt  50  of the biasing assembly  48 , the article  28  continues to move along the primary conveyor belt  32  until the article  28  reaches the labeling units  26 . As previously discussed, the labeling units  26  can be operated to either print different types of labels, or can be configured to each print the identical label. If the labeling units  26  each print the identical label, the labeling units  26  alternate in printing and applying a label to the article  28  such that the speed of the labeling station  24  can be increased. 
     As the article  28  moves in front of one of the print heads  46 , a sensor  116  senses the presence of the article  28 . As shown in FIG. 4, the sensor  116  is mounted to side support  80  by a mounting flange  118 . The mounting flange  118  extends from the side support  80  such that the sensor  116  is positioned above the primary conveyor belt  32  to sense the presence of article  28 . Upon detecting the presence of an article, the sensor  116  generates a signal to trigger the application of a label by the print head  46 . 
     As shown in FIGS. 4 and 5, the print head  46  (shown in phantom) is spaced slightly outwardly from the lateral edge  38  of the primary conveyor belt  32 . Thus, the print head  46  is also spaced slightly outwardly from the first face surface  96  of the article  28  when the article  28  is pressed into contact with the upper guide rail  88  and the lower guide rail  90  by the biasing belt  50 . When the print head  46  applies a label to article  28 , the print assembly  46  applies a jet of air to the label to blow the label onto the first face surface  96 . Since the loops  58  of the biasing belt  50  exert a positive force to press the first face surface  96  of the article  28  into contact with the stationary guide assembly  86 , the first face surface  96  is positioned in a known location relative to the print head  46 , regardless of the size of the article being processed. Thus, the reliability and accuracy of the print head  46  is greatly increased, particularly when articles of different size and shape pass in front of the labeling units  26 . In prior art systems, the articles  28  simply passed in front of the print head  46  and were not positively held in position, as is done by the biasing belt  50 . 
     As was previously discussed, the motor  56  (FIG. 2) operates to rotate the biasing belt  50  at a speed substantially equal to the operating speed of the primary conveyor belt  32 . In this manner, the deformed loops  58  holding the article  28  in contact with the stationary guide assembly  86  continue to press the article  28  into contact with the stationary guide assembly  86  as the article  28  moves along the labeling station  24 . 
     After a label has been applied to the article  28 , the article  28  reaches the downstream roller  54  and is then supported by only the guide members  34  and  36 . The article  28  then continues to move downstream to the stacker mechanisms  27 , as was discussed in the description of FIG.  1 . 
     Although the present invention has been discussed as including a biasing belt  50  in the biasing assembly  48 , it is contemplated by the inventor that other types of biasing mechanisms could also be used, such as spring fingers or other types of force applying mechanisms. In any case, it is important that the biasing assembly  48  applies a lateral force to hold the article  28  in contact with the stationary guide assembly  86  such that a first face surface  96  of the article is positioned in the same spaced relation from the print head  46  for each successive article passing through the labeling station  24 . 
     In addition, it should be understood that the stationary guide rails  88 ,  90  of guide assembly  86  may be replaced with a guide arrangement utilizing rolling elements, or with a guide arrangement having powered elements operating at substantially the same speed as primary conveyor belt  32 . 
     Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.