Patent Publication Number: US-6212859-B1

Title: Packaging machine with rotary top sealer

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to an improved packaging machine concerning the method and apparatus for continuously forming, filling and sealing packages while linked together to a continuous web of material. More specifically the present invention provides an improved horizontal top sealer that allows packages to hold a greater volume of fill while providing a smooth, uniform seal across the top horizontal edge. 
     2. Description of the Prior Art 
     Various prior art packaging machine devices are known in the art. In general, packaging machines are categorized into horizontal and vertical machines depending on the general direction of movement of a continuous web of material. The present invention relates to a horizontal packaging machine with an improved horizontal rotary top sealer and is designed to operate in a continuous manner. 
     In the manufacturing and production of packaged goods, cost factors are highly related to the costs of materials used in the packaging process. In the group of materials commonly found in continuous webs of film material: PET and polyethylene, and paper-polyethylene have heat sealable synthetic films that have a relatively low cost in comparison to other film materials. With these principles in mind, the present machine was developed to produce fusible film packages on a large production basis to be used for packaging products such as food powders, small candies, and the like. The machine and method further enables packages to be formed having a further expanded capacity for receiving an even greater volume of fill than prior packaging methods. 
     A number of U.S. patents have issued to a couple of the above-identified inventors concerning various packaging machine methods and apparatuses, with the following list being only a brief representative list of some issued patents to serve as additional background information in the field of continuously operating horizontal packaging machines: 
     
       
         
           
               
               
               
               
             
               
                   
                   
               
               
                   
                 U.S. Pat. No. 
                 Inventor 
                 Date of Issue 
               
               
                   
                   
               
             
            
               
                   
                 3,453,799 
                 Cloud et al. 
                 July 8, 1969 
               
               
                   
                 3,478,492 
                 Cloud et al. 
                 November 18, 1969 
               
               
                   
                 3,505,776 
                 Cloud 
                 April 14, 1970 
               
               
                   
                 3,597,898 
                 Cloud 
                 August 10, 1971 
               
               
                   
                 3,667,188 
                 Benner and Cloud 
                 June 6, 1972 
               
               
                   
                 5,094,657 
                 Dworak and Cloud 
                 March 10, 1992 
               
               
                   
                 5,722,217 
                 Cloud 
                 March 3, 1998 
               
               
                   
                   
               
            
           
         
       
     
     These and other types of packaging machines used in the past do not offer the flexibility and inventive features of our packaging machine with a rotary top sealer. As will be described in greater detail hereinafter, the method and apparatus of the present invention differs from those previously proposed and employs a number of novel features that render it highly advantageous over the prior art. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a horizontal packaging machine with a rotary top sealer and is designed to operate in a continuous manner utilizing a continuous web of film material for automatically forming, filling and sealing packages. 
     Accordingly, it is an object of this invention to provide an improved method and apparatus for manufacture of filled packages from a continuous web of material, which packages are formed, filled and sealed using a rotary top sealer while linked together to the web. 
     Another object of this invention is to provide an improved method and apparatus for manufacture of filled packages made from oriented polymers such as polypropylene, nylon, and polyester with seals that do not exhibit distortion wrinkles, and more particularly providing a rotary top sealer that allows the filled packages to hold a greater volume of fill while still providing a uniform, smooth seal across the top edge of the filled packages. 
     To achieve the foregoing and other objectives, and in accordance with the purposes of the present invention, a method and apparatus of continuously forming, filling and sealing of packages with a continuous web of film material is provided. The method includes the steps of providing a continuous web of film material and folding the web to provide confronting sides joined along a bottom edge, then forming a vertical seal at spaced intervals along the web thereby providing a series of horizontally disposed adjoining pouches having opposed sidewalls with each pouch unsealed along a top edge. The pouches are then opened by separating the opposed sidewalls and then the pouches are filled with a material. The top edge of each pouch is then sealed to close the filled pouches by training the pouches onto a horizontal rotary sealer having a heated circular sealer plate and progressively forming a continuous horizontal seal as the top edge of each pouch is being continuously moved along with a circumference of the heated circular sealer plate while at the same time applying an adequate temperature to provide a sealing action and allowing the top edge of each pouch to be joined together and smoothly sealed to enclose the filled pouches. 
     In accordance with an aspect of the invention, the horizontal rotary seal former has a heated circular sealer plate mounted for rotation. The heated circular sealer plate has a flat outer surface positioned about its circumference for engagement with an upper portion of the pouches for progressively forming a continuous horizontal seal as the web is continuously moved along with the circumference of the heated circular sealer plate while at the same time applying an adequate temperature to provide a sealing action and allowing the upper portion of the pouches to be joined together and smoothly sealed. 
     Still another feature of this invention concerns the horizontal rotary seal former as described above, wherein the horizontal rotary seal former further includes a land plate and a plurality of lands, the land plate has a diameter slightly smaller than the heated circular sealer plate and is positioned directly below the heated circular sealer plate. The land plate is mounted in corresponding rotation with the heated circular sealer plate, each of the lands has a relatively rectangular shape and has a thickness less than a thickness of the vertical seals on the series of horizontally disposed pouches. The plurality of lands are pivotally mounted at an upper end along the outer edge of the land plate allowing each of the lands to freely pivot radially inward and extend vertically downward from the land plate. The plurality of lands are equally spaced about the circumference of the land plate wherein the distance between each land is equivalent to the distance between the vertical seals on the series of horizontally disposed filled pouches, whereby when the web of horizontally disposed pouches are trained onto the horizontal seal former to join and seal the upper portion of the pouches, the vertical seals extending below the upper edge of the filled pouches will engage with the lands and curve radially inward in engagement with the lands, thereby helping to keep the horizontally disposed pouches properly aligned. 
     Yet another feature of the present invention concerns the packaging apparatus as described above, wherein the horizontal rotary seal former further includes a land stop, the land stop acts to stop each of the lands from pivoting radially inward beyond a predetermined distance. 
     A still further feature of the invention concerns the packaging apparatus as described above, wherein the horizontal rotary seal former further includes a bottom plate. The bottom plate has a diameter equivalent to the heated circular sealer plate and is mounted in corresponding rotation with the heated circular sealer plate. The bottom plate is positioned a predetermined distance below the heated circular sealer plate to allow the bottom edge of the horizontally disposed pouches to rest thereon. 
     An even further feature of the invention concerns the packaging apparatus as described above, wherein the position of the bottom plate in the horizontal rotary seal former is adjustable at varying heights to accommodate pouches of varying lengths. 
     Yet still another feature of the invention concerns the packaging apparatus as described above, further comprising at least one press roller mounted for counter-rotation in pressing engagement against the rotating circumference of the flat outer surface of the heated circular sealer plate in order to help seal and align the upper portion of the web of horizontally disposed pouches. 
    
    
     Other objects, features and advantages of the invention will become more readily apparent upon reference to the following description when taken in conjunction with the accompanying drawings, which drawings illustrate several embodiments of the invention. 
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic perspective view of the present invention; 
     FIG. 2 is a top plan view of the present invention; 
     FIG. 3 is a side plan view of the present invention embodying important features of the present invention taken along line  3 — 3  of FIG. 2; 
     FIG. 4 is a fragmentary perspective view of the rotary top sealer of the present invention; 
     FIG. 5 is a fragmentary cross-sectional side plan view of the gearing mechanism used with the rotary top sealer taken along line  5 — 5  of FIG. 4; 
     FIG. 6 is a fragmentary top plan view of the rotary top sealer gearing mechanism taken along line  6 — 6  of FIG. 5; 
     FIG. 7 is a fragmentary top plan view of the sealer plate and heating element of the rotary top sealer taken along line  7 — 7  of FIG. 5; 
     FIG. 8 is a fragmentary top plan view of the rotary top sealer as taken along line  8 — 8  of FIG. 5 embodying further important features of the present invention; 
     FIG. 9 is a fragmentary top plan view of the rotary top sealer as taken along line  9 — 9  of FIG. 5; 
     FIG. 10 is an enlarged partial cross-sectional side view illustrating the connection of the wear plate to the hydraulic cylinders taken along line  10 — 10  of FIG. 9; 
     FIG. 11 is an enlarged partial perspective view of the rotary top sealer illustrating how the lands are connected to the land plate; 
     FIG. 12 is an enlarged partial cross-sectional side view taken along line  12 — 12  of FIG. 8 illustrating the land stops of the rotary top sealer; 
     FIG. 13 is an enlarged partial cross-sectional side view illustrating how the land stops of the rotary top sealer can be adjusted; 
     FIG. 14 is an enlarged partial cross-sectional side view illustrating how the height of the bottom plate can be adjusted to accommodate packages of different heights; 
     FIG. 15 is an enlarged partial cross-sectional side view illustrating how packages are sealed and rotated about the rotary top sealer of the present invention; 
     FIG. 16 is a perspective view of a sealed package using the rotary top sealer of the present invention; and 
     FIG. 17 is a perspective view of a sealed package utilizing the prior art of sealing top edges of packages. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, a packaging machine  10  is illustrated in FIG.  1 . The present machine  10  is a horizontal type packaging machine and is capable of producing filled packages  12  at a high rate of production. The packages  12  are produced from a continuous strip or web of film material  14  or from several continuous webs of laminated film materials, as desired. The web is formed of film materials such as: PET and polyethylene; paper-polyethylene; or any other types of sealable film material, which provides for an inexpensive packaging material. Additionally, the web may be pre-printed. 
     A coiled roll of the continuous web  14  of film material is initially provided. A suitable strip plow  16  acts to fold the web  14  to provide confronting sides  18  joined along a bottom edge  20  of the web  14 . A guide roller  22  then directs the web onto a rotating vertical seal former  24  to form a plurality of vertical seals  25  extending from the bottom edge of the web to the top edge of the web. The vertical seal former has a plurality of elongated circumferentially spaced vertical sealers  26  located at an outside surface of the vertical seal former  24 , as best illustrated in FIG.  1 . 
     In order to form vertical seals  25 , the web  14  is pressed against the elongated circumferentially spaced vertical sealers  26  to progressively form vertical seals  25  as the web is being continuously moved with the rotating vertical seal former  24  while at the same time applying an adequate temperature to provide a sealing action and allowing the area of the film being sealed to be progressively formed or cooked. As the vertical seals are formed, the confronting sides  18  of the web  14  are melted together along the area of the vertical sealers  26 , with the vertical sealers then melting through the web  14  to form a vertical seal  25  along each adjacent side of the vertical sealers  26 . Once the vertical seals  25  have been completed, a series of horizontally disposed pouches  28  have been produced. It is to be understood that other types of pouch creating methods can be employed with the features of the present invention. 
     The newly formed horizontally disposed pouches  28  are now directed towards the filling station  30 . The filling station comprises of a vacuum transfer wheel  32  positioned directly beneath a filler transfer wheel  34 . As the pouches  28  enter the filling station  30 , the pouches are opened by the vacuum transfer wheel  32  (FIG. 2) by separating the opposing sidewalls of each pouch. It is to be understood that the pouches  28  can be opened by a variety of different methods, including forcing air into the top edge of each pouch, as well as providing a vacuum suction on a central portion of the opposing sidewalls on each pouch to separate the sidewalls from each other. 
     As the newly opened pouches  28  are rotated about the filling station  30 , each of the pouches are then progressively filled from the filler transfer wheel  34  through filling spouts  36  positioned directly above a central portion of the opened pouches. In the present invention, the pouches  28  can be filled to a greater extent and allowing the pouches to take on a bulged shape or appearance, as shown in FIG.  15 . It is to be understood that other types of filling methods can be employed with the features of the present invention. 
     After each pouch  28  has been filled, the web  14  is then immediately directed around a horizontal rotary top sealer  37 . The rotary top sealer  37  can be positioned adjacent to the filling station  30  and can be directly tied mechanically to the filling station gearing mechanism in order to have consistently aligned rotating units. As can be seen in FIGS. 5 and 6, the filler transfer wheel is timed to work with the rotary top sealer shaft  40  through a series of chains  42 ,  44 ,  46 , and gears and sprockets  48 ,  50 ,  52 ,  54 ,  56 ,  58 ,  60 . As is illustrated in FIG. 6, the chains, gears and sprockets provide a reverse rotation of the rotary top sealer relative to the filling station. The filling station chain  42  is connected from the filling station  30 , and through a series of chains and gears, powers the rotary top sealer shaft  40 . This gearing mechanisms enables the filled packages to smoothly transfer from the filling station  30  to the rotary top sealer  37 . Various different motors and other different methods and designs can be employed to power the devices of the present invention and are not the subject of the invention herein disclosed. 
     Excellent results can be obtained when the rotary top sealer  37  is located as close to the filling station  30  as possible in order to minimize the length of unsupported web between the two units. The lands  64  (FIG. 4) of the rotary top sealer  37  are in phase with the lands  65  (FIG. 2) on the vacuum transfer wheel. This provides a smooth transition of the web to the rotary top sealer  37 . Since the lands  64  of the rotary top sealer only contact the vertical seal of the pouch product, disturbance within the pouch  28  is minimized. 
     Each of the lands  64  has a relatively rectangular shape and has a thickness less than a thickness of the vertical seals on the series of horizontally disposed pouches  28 . A land plate  66  is positioned directly below the heated circular sealer plate  80 . The land plate  66  has a diameter smaller than the heated circular sealer plate and is mounted in corresponding rotation with the sealer plate  80 . Each of the lands  64  are pivotally mounted with a mounting bracket  67  and a pivot pin  68  at an upper end along the outer edge of the land plate  66  allowing each of the lands to freely pivot radially inward and extend vertically downward. The plurality of lands are equally spaced about the circumference of the land plate wherein the distance between each land is equivalent to the distance between the vertical seals on the series of horizontally disposed adjoining pouches  28 , whereby when the horizontally disposed adjoining pouches are trained onto the horizontal rotary sealer to join and seal the upper portion of the adjoining pouches, the vertical seals extending below the top edge of the pouches will engage with the lands  64  and curve radially inward in engagement with the lands, thereby helping to keep the horizontally disposed adjoining pouches properly aligned. 
     As can be seen in FIGS. 5,  12 ,  13 ,  14 , and  15 , the rotary top sealer lands  64  are allowed to pivot inward until they rest against a land stop  69 . Land stop settings are adjustable in order to accommodate different pouch fills. The land stops  69  are mounted in a bottom plate  70  and are allowed to slide through a bearing  72  in an inward radial direction. 
     The land stops  69  are spring loaded with coiled springs  71  inwardly against a non-rotating fixed cone  74 . The vertical height of the cone  74  can be changed (FIGS. 5,  14 ) while the rotary top sealer  37  is running through the use of two screw assemblies  75 ,  76 . This then allows uniform adjustment of the inward pivot movement of the lands. 
     Six posts  78  which are mounted to the sealer plate  80  provide the mounting for a bottom plate  70 . The bottom plate  70  has a diameter similar to the sealer plate  80  and contains clearance slots  82  for the lands and holes with bushings  84  for the posts  78  to slip through. This allows the bottom plate to have a corresponding equivalent rotation with the sealer plate  80 . Springs  86  are fitted over the posts  78  and hold the bottom plate  70  against the wear plate  88 . The wear plate  88  is mounted to four hydraulic cylinders  90  which provide dynamic adjustment. This adjustment allows the bottom plate to move up and down and is necessary for package height and package fill changes. For clarity purposes, FIGS. 5 and 14 do not show all of the posts and lands extending around the rotary top sealer  37 . 
     The sealer plate  80  contains a heating element  81  to heat the sealer plate, particularly the outer edge, and is designed to be slightly larger than the land plate  66  to help iron out wrinkles in the packages  28  that are being sealed, thereby providing a smooth top seal. Since the smooth top seal is created by training the upper edge of the pouches along a circular sealer wherein the top edge is progressively stretched and closed, the packages can then accommodate a greater amount of product fill than prior top sealing devices. This sealing method provides for a filled package  100  (FIG. 16) that has a smooth hermetic top seal  102 . Using the same amount of package filling, the prior art sealing methods does not consistently provide a uniform hermetic seal as is shown in the package  104  and seal  106  in FIG.  17 . The lands  64  and the bottom plate  70  help keep large pouches with a heavier product fill properly aligned and supported as the top seal is created. Smaller packages with a light fill may not require the use of lands or the bottom plate. As long as there is a sufficient tension in the web of pouches traveling around the top sealer, lighter and smaller packages may not require the support provided by the lands and the bottom plate. However, the use of a circular sealer enables the packages to contain a greater amount of fill then prior sealing devices allow. 
     As the web of pouches is trained onto the horizontal rotary top sealer  37 , the heated sealer plate  80  progressively forms a continuous horizontal seal as the top edge of each pouch is continuously moved radially and circumferentially about the outer edge of the heated circular sealer plate  80 . The heated circular sealer plate  80  provides an adequate temperature to provide a sealing action to the top edge of each pouch contacting the sealer plate and smoothly seals and encloses the filled pouches. 
     Depending on the size of the packages used and the amount of fill placed within the packages, backup rollers or press rollers  108  may need to be used to provide pressure against the upper edge of the web of pouches  28  and the sealer plate  80 . The backup rollers are mounted for counter-rotation pressing engagement against the rotating circumference of the heated circular sealer plate  80  in order to pinch and seal the top edge of the pouches. Excellent results are obtained when using a backup roller with larger packages containing a heavier fill. Smaller packages with a light powder fill may not require the use of backup rollers to create a uniform top seal, and wherein the web of packages has a sufficient tension to create a proper seal. 
     In the design of the presently disclosed invention, the web of pouches  28  exits the rotary top sealer unit  37  180 degrees from the entering point. It is not essential for the web of pouches to travel a full 180 degrees around the rotary top sealer, but it is necessary for the upper edge of film material to be in contact with the sealer plate for a predetermined amount of time over a portion of the sealer plate in order to provide an adequate seal. Excellent results can be obtained when a film/film structure such as PET-polyethylene material is in contact with the sealer plate having a temperature between 400-410 degrees for approximately one (1) second. Other types of fusible film materials may require more or less time to adequately seal the packages and appropriate adjustments regarding the temperature of the sealer plate and the speed of rotation can be made. 
     After the top seal has been created, the web of sealed packages then continues onto a cutter that separates the packages from the continuous web, wherein the packages are then ultimately boxed for distribution. 
     Although the invention has been described by reference to some embodiments, it is not intended that the novel device be limited thereby, but that modifications thereof are intended to be included as falling within the broad scope and spirit of the foregoing disclosure, the following claims and the appended drawings.