Patent Publication Number: US-2013247520-A1

Title: Packaging machine

Description:
RELATED APPLICATIONS 
     This application is a divisional application of U.S. Ser. No. 13/311,108, filed Dec. 5, 2011, issued Nov. 13, 2012, as U.S. Pat. No. 8,307,617 which is a divisional of U.S. Pat. No. 8,069,635, issued Dec. 6, 2011, which is a divisional of U.S. Pat. No. 7,654,064, issued Feb. 2, 2010 which claims priority to U.S. Provisional Application No. 60/971,761 filed Sep. 12, 2007, the entire disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to packaging and in particular to a method and apparatus for forming packages without assistance from a source of pressurized air. 
     BACKGROUND OF THE INVENTION 
     Various methods and apparatus for packaging articles in plastic bags are available. In one packaging method, the bags form part of a continuous plastic web. Each bag is connected to an adjacent bag along a line of weakness. Typically, the bags define an opening on one face through which the bag is loaded. Some existing bagging machines are powered by both electricity and compressed air. One advantage of bagging machines that utilize compressed air is that a powerful burst of air can be provided at the opening of the bag to separate the plies of the bags and open the bags for loading. 
     SUMMARY 
     The present application discloses methods and apparatus for forming packages from a web of preformed bags. In one exemplary method of forming packages from a web of preformed bags, a first bag is held open with air. A product is loaded into the first bag that is held open with air. An opening of the first bag is sealed. A next bag is indexed such that an opening of the next bag is proximate to an engagement member. The web is engaged with the engagement member to pre-open the next bag. The web is disengaged by the engagement member. The next bag is opened with air for loading. 
     This method can be performed by a wide variety of different apparatus. In one exemplary embodiment, the apparatus comprises a supply of a web of preformed bags. An indexing mechanism moves the web along a path of travel. A blower is positioned to sequentially blow air into the bags of the web to open the bags. An engagement member is moveable from an engaged position where the engagement member engages the web and a disengaged position where the engagement member is spaced apart from the web. A sealer seals loaded bags to form packages. A controller is in communication with the indexing mechanism, the engagement member, and the sealer. The controller is programmed to actuate the sealer to seal an opening of the first bag, index a next bag such that an opening of the next bag is proximate to the engagement member, and engage the web with the engagement to pre-open the next bag. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a flow chart that illustrates a process of loading bags with a product, sealing the bags, and separating the bags from a web of bags; 
         FIG. 1A  is a schematic illustration of an exemplary elongated web of preformed interconnected bags; 
         FIG. 1B  is a view of the elongated web taken along lines  1 B- 1 B in  FIG. 1A ; 
         FIG. 2  is a view of an exemplary package; 
         FIG. 3  is a view of the package taken along lines  3 - 3  in  FIG. 2 ; 
         FIG. 4  is a schematic illustration of an exemplary apparatus for making packages from an elongated web of preformed interconnected bags; 
         FIG. 5  is a view of the apparatus taken along lines  5 - 5  in  FIG. 4 ; 
         FIG. 6  is a schematic illustration of the apparatus with the bag in an open condition for loading with a product; 
         FIG. 7  is a view of the apparatus taken along lines  7 - 7  in  FIG. 6 ; 
         FIG. 8  is a schematic illustration of the apparatus with an engagement member positioned to reduce a volume of air in the loaded bag; 
         FIG. 9  is a view of the apparatus taken along lines  9 - 9  in  FIG. 8 ; 
         FIG. 10  is a schematic illustration of the apparatus with the bag being sealed to enclose the product in the package; 
         FIG. 11  is a view of the apparatus taken along lines  11 - 11  in  FIG. 10 ; 
         FIG. 12  is a schematic illustration of the apparatus pulling the web away from the loaded bag to separate the loaded bag from the web; 
         FIG. 13  is a view of the apparatus taken along lines  13 - 13  in  FIG. 12 ; 
         FIG. 14  is a schematic illustration of the apparatus releasing an exemplary package; 
         FIG. 15  is a view of the apparatus taken along lines  15 - 15  in  FIG. 14 ; 
         FIG. 16  is a schematic illustration of the apparatus with a bag positioned for pre-opening by engagement with an engagement member; 
         FIG. 17  is a view of the apparatus taken along lines  17 - 17  in  FIG. 16 ; 
         FIG. 18  is a schematic illustration of the apparatus with a bag being pre-opened by engagement with an engagement member and reverse indexing of a drive; 
         FIG. 19  is a view of the apparatus taken along lines  19 - 19  in  FIG. 18 ; 
         FIG. 20  is a schematic illustration of the apparatus with the bag being blown open by a source of air; 
         FIG. 21  is a view of the apparatus taken along lines  21 - 21  in  FIG. 20 ; 
         FIG. 22  is a schematic illustration of the apparatus with the bag in the open condition for loading with a product; 
         FIG. 23  is a view of the apparatus taken along lines  23 - 23  in  FIG. 22 ; 
         FIG. 24  illustrates an engagement member with an optional device that helps the engagement member pre-open the bags with the engagement member spaced apart from the web; 
         FIG. 25  illustrates an engagement member with an optional device that helps the engagement member pre-open the bags with the engagement member in contact with the web; 
         FIG. 26  illustrates an engagement member with an optional member that helps the engagement member pre-open the bags with the engagement member spaced apart from the web; and 
         FIG. 27  illustrates an engagement member with an optional member that helps the engagement member pre-open the bags with the engagement member in contact with the web. 
     
    
    
     DETAILED DESCRIPTION 
     The present application relates to a method  8  ( FIG. 1 ) and apparatus  10  ( FIGS. 4 and 5 ) for making packages  12  ( FIGS. 2 and 3 ) from an elongated web  16  ( FIGS. 1A and 2A ) of preformed interconnected bags  18 . In an exemplary embodiment, the web  16  is engaged to move one ply of the web with respect to the other ply of the web to “pre-open” the bag and make opening of the bag  18  with air to receive products easier. As a result, air moving at a lower volumetric flow rate can be used to open the bags. For example, air provided by a relatively small electric fan or blower can be used to open the “pre-opened” bag, instead of air provided under relatively high pressure by an air compressor. In one embodiment, the apparatus  10  is powered solely by electricity, is not connected to a source of pressurized air, and does not include an air compressor. 
     The packages  12  can be made from a wide variety of different types of webs  16  of preformed interconnected bags  18 . In the example illustrated by  FIGS. 1A and 1B , each preformed bag  18  is defined by first and second plies  20 ,  22  of the web  16 . First and second side edges  24 ,  26  of the web hermetically join the first and second plies. Preformed seals  28  extend between the first and second side edges  24 ,  26 . A line of separation  30 , such as a cut in the first ply extends between the first and second side edges  24 ,  26 . A line of weakness  32 , such as a line of perforations in the second ply extends between the first and second side edges  24 ,  26 . The web  16  of preformed bags  18  illustrated by  FIGS. 1A and 1B  is one example of the wide variety of different webs that may be used. Examples of acceptable webs of preformed interconnected bags include, but are not limited to, the webs disclosed in U.S. Pat. No. 3,254,828 to H. Lerner and U.S. Pat. No. 5,957,824 to B. Lerner et al., which are incorporated herein by reference in their entirety. 
     The web may be formed of any suitable material. Examples of suitable materials include, but are not limited to, plastic materials, polyethylene, cellophane, vinyl films, pliofilms, cellulose acetate film, polystyrene, polypropylene, and any heat sealable material. 
     Referring to  FIGS. 2 and 3 , an exemplary package  12  includes a sealed compartment  36 . The package  12  may have any number of compartments. Product  40  is disposed in the compartment  36 . The illustrated product  40  is a plurality of bolts. However, the package  12  may contain any product. The compartment is defined by the first and second side edges  24 ,  26 , the preformed seal  28 , and a seal  44  that is formed after the product  40  is loaded into the bag. In the example, the seal  44  extends from the first side edge  24  to the second side edge  26  to hermetically seal the compartment  36 . In another embodiment, the dividing seal  28  may not extend all the way from the first side edge to the second side edge or may be intermittent to allow communication between the compartment  44  and external air or the compartment  44  and another optional compartment of the package. 
       FIG. 1  is a flow chart  14  that illustrates a method  8  of making packages. Any one or more of the steps of the method illustrated by  FIG. 1  may be omitted and/or the order of the steps may be changed without departing from the spirit and the scope of the present invention. That is, steps of the method illustrated by  FIG. 1  may be omitted, modified or reduced. For example, any method that moves one layer  22  with respect to the other layer  20  (or vice versa) to allow the bags to be more easily opened with air can be used. The flow chart refers to the apparatus  10  shown in  FIGS. 4-23  being operated to make packages  12  from an elongated web  16  of preformed interconnected bags  18 . However, any apparatus can be used that performs the method shown in  FIG. 1 . The concept of the apparatus  10  can be implemented in any of a wide variety of packaging machines. For example, U.S. Pat. No. 3,254,468 to H. Lerner, U.S. Pat. No. 4,928,455 to Gereby et al., U.S. Pat. No. 5,341,625 to Kramer, U.S. Pat. No. 5,394,676 to B. Lerner et al., U.S. Pat. No. 6,543,201 to Cronauer et al., U.S. Pat. No. 6,742,317, U.S. Pat. No. 5,394,676, U.S. Pat. No. 5,371,521, and U.S. Pat. No. 4,899,520 disclose packaging machines that can be modified in accordance with the present invention to make packages from an elongated web of preformed interconnected bags and are all incorporated herein by reference in their entirety. 
     Referring now to  FIGS. 4-7 , the illustrated apparatus  10  includes a supply  50  ( FIG. 6 ) of the elongated web  16  of preformed interconnected bags  18 , an indexing mechanism  52 , an opening arrangement  54 , a sealing arrangement  56 , and a controller  58 . The supply  50  comprises the elongated web  16  that is rolled or folded to stage a relatively large amount of the web in a relatively small space. The web  16  is routed from the supply  50  along a path of travel P to the indexing mechanism  52 . The indexing mechanism  52  receives the web  16  from the supply and moves the web along the path of travel P. The indexing mechanism  52  may take a wide variety of different forms. For example, any indexing mechanism that can be controlled to index bags of the web to selected positions along the path of travel may be used. In the illustrated example, the indexing mechanism comprises a pair of rollers  60  that form a nip that engages the web  16 . The rollers  60  are selectively driven by a motor (not shown) to index bags of the web to selected positions along the path of travel P. 
     Referring to  FIGS. 4 and 5 , the opening arrangement  54  is positioned along the path of travel P to open each bag that is to be loaded and sealed. In the illustrated embodiment, the opening arrangement  54  comprises a blower  400  and an engagement device  402 . However, the opening arrangement  54  may take a wide variety of different forms. 
     Referring to  FIGS. 4 and 5 , the controller  58  is in communication with the indexing arrangement  52 , the opening arrangement  54 , and the sealing arrangement  56 . The controller  58  controls the indexing arrangement  52 , the opening arrangement  54 , and the sealing arrangement  56  to convert the preformed bags  18  into packages  12 . A wide variety of controllers can be used and programmed to control the indexing arrangement  52 , the opening arrangement  54 , and the sealing arrangement  56  as described herein. For example, the controller and controller algorithms described in U.S. Pat. No. 5,341,625 to Kramer can be modified to control the indexing arrangement  52 , the opening arrangement  54 , and the sealing arrangement  56  to perform the method  8  of forming packages. 
     Referring to  FIGS. 1 ,  6  and  7 , each bag  18  is held open with air at a position where the bag is loaded with a product  40 . The opening of the bags  18  is described in more detail below. When the bag  18  is positioned at the load position and is held open by air, the product  40  is loaded into the bag  18 . The product may be loaded manually or automatically. In the illustrated embodiment, the position where the bag  18  is loaded is also the position where bag  18  is sealed. In another embodiment the position where the bag is loaded is different than the position where the bag is sealed. In this embodiment, the controller  58  causes the indexing mechanism  52  to move the bag  18  to the seal position after the bag is loaded with product  40 . 
     In an exemplary embodiment, once the product is loaded in the bag  18 , an operator may provide a signal to the controller  58  that indicates that loading is complete or completion of loading may be automatically detected. The apparatus  10  may be configured to allow the operator to provide the completed loading signal to the controller in a wide variety of different ways. For example, the apparatus may have a control foot pedal (not shown) or the sealing arrangement  56  may have a portion that the operator can push on to indicate that loading is complete and it is time to seal the package. Similarly, the apparatus can be configured to automatically detect completed loading and provide the controller with a signal that indicated this fact. For example, the apparatus may include a counter or may weigh the package to detect completed loading. The signal from the operator or detection of completed loading is communicated to the controller  58 , which may cause actuation of both the engagement device  402  as shown in  FIGS. 8 and 9  and the sealing arrangement  56  as shown in  FIGS. 10 and 11  as described in more detail below. 
     Referring to  FIGS. 8 and 9 , once in the seal position, the controller  58  optionally causes a motor or actuator  406  of the engagement device  402  to move an engagement member  404  into engagement with the web  16 . The engagement between the engagement member  404  and the web  16  inhibits further air from the blower  400  from moving into the open bag  18 , and thus functions as an air restrictor. As a result, the amount of air in the bag  18  diminishes as illustrated by  FIG. 8  before the seal is formed. 
     Referring to  FIGS. 10 and 11 , the sealing arrangement  56  is positioned along the path of travel P to provide the seal  44  ( FIG. 2 ). The sealing arrangement  56  may take a wide variety of different forms. For example, any mechanism that applies heat to the web to seal the first and second webs together to form the seal  44  may be implemented. In the illustrated embodiment, the sealing arrangement comprises a heated bar  68  that is selectively moved into and out of engagement with a base member  70 . When the web is in the seal position, the controller  58  controls the sealing arrangement  56  to clamp the web  16  between the heated bar  68  and the base member  70 . Heat is applied to the web to seal the plies of the web together between the first side edge  24  and the second side edge  26 . The first and second plies  20 ,  22  are sealed together to form the compartment  36 . In the exemplary embodiment, the controller  58  causes the motor or actuator  406  of the engagement device  402  to move the engagement member  404  away from the web  16  once the web  16  is clamped by the heated bar. 
     Referring to  FIGS. 12 and 13 , the controller  58  controls the indexing mechanism  52  to separate the formed package  12  from the web  16 . The second ply  22  is broken along the line of weakness  32  to separate the package  12  from the elongated web  16  of interconnected bags  18 . The controller  58  controls the indexing arrangement  52  to pull the web  16  away from the bag  18  as indicated by arrows  74  while the bag is clamped by the sealing arrangement  56  in an exemplary embodiment. The bag  18  breaks free of the web  16  along the line of weakness  32 . Referring to  FIGS. 14 and 15 , the controller  58  controls the sealing arrangement  56  to release the formed package  12 . 
     Referring to  FIGS. 16 and 17 , the controller  58  controls the indexing mechanism  52  to index the web  16  forward until the opening  30  of the next bag  18  is just below the engagement member  404  of the engagement device  402  in the exemplary embodiment. In alternate embodiments, the opening  30  is indexed to other positions. The opening  30  can be indexed to any position where engagement of the web by the engagement member  404  and/or movement of the web by the indexing arrangement  52  causes the bag to pre-open. For example, the opening  30  may be substantially aligned with the engagement member  404   402  or the opening may be positioned slightly above the engagement member. 
     Referring to  FIGS. 18 and 19 , the controller  58  then causes the motor or actuator  406  of the engagement device  402  to move the engagement member  404  into engagement with the web. The engagement of the web  16  with the engagement member  404  alone can be configured to cause the layers  20 ,  22  of the web to move relative to one another to pre-open the bag and facilitate easy opening of the bag with air. In an exemplary embodiment, the controller  58  causes the indexing mechanism  52  to pull on the web as indicated by arrows  412  while the engagement member  404  is in engagement with the web  16  to cause the layers  20 ,  22  to move with respect to one another and pre-open the bag. In another embodiment, the indexing mechanism moves the web in the opposite direction to pre-open the bag. 
     The relative movement of the layers  20 ,  22  of the web may manifest in a wide variety of different ways.  FIG. 19  shows that the layer  20  may wrinkle or pucker at the opening  30  when the web is pulled against the engagement member  404 . This wrinkling or puckering creates enough of a space between the two layers at the opening  30  that a small amount of air flow will easily open the bag  18  for filling. The engagement between the engagement member  404  and the web  16  can be at any location on the web that facilitates movement of the two layers  20 ,  22  at the opening. For example, the engagement can occur a significant distance from the opening  30  and still facilitate movement of the layers  20 ,  22  at the opening to pre-open the bag  18 . In an embodiment, a separate engagement device that is used for pre-opening of the bags is included in addition to an engagement device that is used to reduce the amount of air in the package after the bag is loaded as described above. In another embodiment, the engagement device  402  does not function to reduce the amount of air on the loaded package and the engagement device functions primarily to engage the web to facilitate pre-opening of the web as described above. 
     The engagement device  402  can take a wide variety of different forms. The engagement device  404  may be a pneumatic, hydraulic, or electric actuator with an extendable portion that engages the web to pre-open the bags or a driven cam that rotates to engage the web and pre-open the bags. The engagement device  404  can be any device that moves to engage the web to pre-open the bags. 
     Referring to  FIGS. 24-27 , in some embodiments the indexing arrangement is not reversed to pre-open the bags and the engagement device includes an optional device  2400  ( FIGS. 24 and 25 ) or member  2600  ( FIGS. 26 and 27 ) that helps the engagement member  404  pre-open the bags. Referring to  FIGS. 24 and 25 , the optional device  2400  may be a powered device with a portion  2402  that forces the front layer  20  of the web upward or downward when the engagement member  404  engages the web. In the example illustrated by  FIGS. 24 and 25 , the portion  2402  moves downward as indicated by arrow  2404  to help pre-open the web. The optional member  2600  may be a spring member or spring biased member that forces the front layer of the web upward or downward when the engagement member  404  engages the web. In the example illustrated by  FIGS. 26  and  27 , the optional member  2600  comprises a spring arm or leaf spring that is compressed and extends to move the front layer of the web downward as indicated by arrow  2604  to help pre-open the web. 
     Referring to  FIGS. 20 and 21 , the controller causes the motor or actuator  406  of the engagement device  402  to move the engagement member  404  out of engagement with the web. Air from the blower  400  is forced between the pre-opened plies  20 ,  22  at the opening  30  of the bag. The air is forced between the plies through the opening  30  to inflate the bag  18  for depositing product  40  therein. 
     Referring to  FIGS. 22 and 23 , the controller  58  indexes the web  16 , with the open bag  18  to the load position. The bag is held open by the air and the cycle begins again. The controller may repeat the method as required to produce as many packages are needed from the web. 
     It should be understood that the embodiments discussed above are representative of aspects of the invention and are provided as examples and not an exhaustive description of implementations of an aspect of the invention. 
     While various aspects of the invention are described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects may be realized in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present invention. Still further, while various alternative embodiments as to the various aspects and features of the invention, such as alternative materials, structures, configurations, methods, devices, software, hardware, control logic and so on may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the aspects, concepts or features of the invention into additional embodiments within the scope of the present invention even if such embodiments are not expressly disclosed herein. Additionally, even though some features, concepts or aspects of the invention may be described herein as being a preferred arrangement or method, such description is not intended to suggest that such feature is required or necessary unless expressly so stated. Still further, exemplary or representative values and ranges may be included to assist in understanding the present invention however, such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly stated.