Abstract:
A method for dispensing moisture sensitive materials employs a packaging module comprising an outer carton and an inner flexible enclosure, which is substantially impermeable to moisture and is filled with one part of an adhesive. The enclosed is loaded on a mobile cart and the one part adhesive is supplied to a pump/mixer without exposure to moisture in the atmosphere. The dispensing method can be used in conjunction with mechanized adhesive application equipment for the construction trades.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a divisional of U.S. patent application Ser. No. 13/904,640 filed on May 29, 2013, which is a continuation of U.S. patent application Ser. No. 13/435,432 filed on Mar. 30, 2012, now U.S. Pat. No. 8,474,658, which is a continuation of U.S. patent application Ser. No. 11/818,451 filed on Jun. 14, 2007, now U.S. Pat. No. 8,167,170, which claims the priority of U.S. Provisional Patent Application No. 60/813,788 filed on Jun. 15, 2006, the disclosure of which is incorporated in its entirety by reference. 
     
    
     FIELD OF THE TECHNOLOGY 
       [0002]    This application is directed to a packaging system for moisture-sensitive materials, and more particularly, to a dispensing system for moisture-sensitive adhesive materials used in the construction industry. 
       BACKGROUND OF THE INVENTION 
       [0003]    In the construction industry, most moisture-sensitive materials, such as adhesive components, are packaged in a variety of sealable containers to prevent the contents from absorbing water from the atmosphere or moisture that collects on the surfaces of dispensing systems. Moisture commonly migrates into the fittings, nozzles and conduits of such dispensing systems. The dispensing system becomes clogged and the dispensing qualities are degraded to the extent that the system must be disassembled and cleaned. Significant costs and inefficiencies result from having to remove moisture which collects in the components of the dispensing system. 
         [0004]    If the moisture-sensitive material is to remain viable overtime, the user has to make sure that the packaging is tightly closed during periods of non-use. However, moisture-sensitive materials are inherently difficult to store after opening the original packaging, so in many cases, the unused portion is discarded after a construction job is completed. If moisture-sensitive materials are not discarded after opening the primary container, the material begins to chemically degrade, which can negatively affect the performance and physical properties of the remaining material. Additionally, the necessity of routinely discarding the unused portions of moisture-sensitive materials is costly, inconvenient, and environmentally unsound. 
       SUMMARY 
       [0005]    Briefly stated, a method of dispensing a moisture-sensitive adhesive with a mobile applicator system having a receiving tray comprises providing a package having an outer container body, an inner flexible enclosure that is substantially impermeable to moisture and has an opening enclosing a cap and contains one part of an adhesive. The method further comprises loading the enclosure onto the receiving tray of the mobile applicator system, and positioning the enclosure so that the cap is disposed generally below the enclosure. A method step further includes connecting a conduit for communication through the opening without exposing said one part to the atmosphere. The method additionally comprises mixing said one part with a second part to form an adhesive and dispensing said adhesive. 
         [0006]    In one embodiment, the cap has a fitting with a valve and the method comprises lifting the valve to permit communication of said one part into the conduit. The method may further comprise repeating the steps of providing a package, loading the enclosure, positioning the enclosure and connecting a conduit for a second package with a second part. A step of disconnecting the conduit from communication through the opening is undertaken without exposing the one part in the flexible inner enclosure to the atmosphere. 
         [0007]    In another embodiment, the method for dispensing a two-part adhesive comprises providing a cart having a tray defining a first and second tray apertures and mounting a pump assembly having a pair of inlets and a pair of outlets, each outlet communicating with a hose communicating with a common dispenser. The method comprises providing a first package enclosing an inner enclosure with a first cap with a fitting and containing a first adhesive component of said two-part adhesive and providing a second package enclosing an inner enclosure with a second cap with a fitting and containing a second adhesive component of the two-part adhesive. The method comprises positioning the first and second enclosures on the tray and positioning the first and second fittings so that they extend through the first and second apertures, respectively. The method further comprises connecting a first conduit for communication via first valve connector assembly between the first enclosure and connecting a second conduit for communication via second valve connector assembly between the second enclosure and the inlets. The method also comprises pumping the first and second components wherein the components traverse through the first and second tray apertures to the hoses, mixing the components to form a two-part adhesive, and dispensing the two-part adhesive through the dispenser. 
         [0008]    The dispensing method also comprises disposing said first enclosure and second enclosure in generally aligned adjacent disposition on the tray. The dispensing method also comprises connecting at least one conduit to a connector assembly without exposing the component in the enclosure to the atmosphere. The dispensing method also preferably comprises lifting a valve of the connector assembly. 
         [0009]    An adhesive dispenser system for moisture-sensitive materials, such as construction adhesives, is provided. The adhesive dispenser system employs a packaging module which protects the contents therein from moisture in the atmosphere during use as well as during pre- and post-use storage and shipping. In one preferred embodiment, a packaging module comprises an outer container body or carton and an inner bag or bladder made of a water-impermeable flexible sheet material. The bladder has a truncated spout which is closed by a cap which is preferably valved. The bladder is filled with one part of an adhesive. The outer container body is preferably equipped with a handle, an opening to provide access to the spout and a window to allow inspection of the contents remaining in the bladder. The packaging module is adapted for efficient use with mechanical or motorized applicator systems. 
         [0010]    The inner bladder receives and contains the moisture-sensitive material during shipping, use, and storage. It is also preferred that the spout has sidewalls extending upwardly to form a ridged neck portion and that the cap be threaded to the spout. Preferably, the spout and cap are manufactured from a durable plastic material. The spout can be closed or sealed either by use of a valved cap or similar sealing means. The spout via the cap is re-sealable after a first use such that the material therein remains in substantially the same condition as it was upon the first opening or first use of the material. 
         [0011]    Briefly stated, one embodiment of a dispensing apparatus for a two-part adhesive comprises a cart having a tray. The carts mount a pump assembly which has a pair of inlets and a pair of outlets which communicate with a mixer/applicator gun. A first package encloses a bladder with an opening and which contains a first adhesive component. A second package encloses a bladder with a second opening and which contains a second adhesive component. The packages are each received on the tray. A conduit communicates via a first valve connector assembly between the opening of the package assembly and an inlet to the pump. A second conduit communicates via a second valve connector assembly between an opening of the second package and a second inlet to the pump. The first and second adhesive components are pumped by the pump assembly to a mixer/gun assembly and dispensed therefrom. 
         [0012]    At least one package has a corrugated configuration. The package has a general rectangular shape with a handle mounted at one side. The package also has a window to permit inspection of the adhesive component contained in the corresponding bladder. The tray has a retention flange which surrounds the packages with the first and second packages being generally aligned in adjacent side disposition on the tray. At least one of the connector assemblies upon connection to the conduit does not permit exposure of the component in the bladder to the atmosphere. The connector assembly comprises a poppet valve and a snap-fit type connection. The snap-fit type engagement closes off the corresponding opening upon disconnecting the associated conduit from the opening. A hose connects the outlet to a mixer. The cart may further have a pair of wheels and handlebars for facilitating movement across a surface. 
         [0013]    A method of dispensing a moisture sensitive adhesive with a mobile applicator system comprises providing a package having an outer container and an inner flexible enclosure that is substantially impermeable to moisture. The enclosure has an opening and is closed by a cap. The enclosure contains one part of an adhesive. The package is inverted. The package is then loaded onto a tray of the mobile applicator system. A conduit is connected for communication through the opening without exposing the one part to the atmosphere. The one part is mixed with the second part to form an adhesive and the adhesive is dispensed under pressure for application. 
         [0014]    The conduit connecting step may employ lifting a valve to permit communication of one part into the conduit and implementing a snap fit connection between fittings of the cap and the conduit. The conduit may be disconnected from communication with the opening without exposing the one part in the inner enclosure to the atmosphere. 
         [0015]    A packaging module comprises a carton having a box-like shape with one side having an opening. A water impermeable enclosure is disposed in the carton and has a spout alignable with or disposed in the opening and enclosed by a cap with a valve. A moisture sensitive part of the adhesive is disposed in the enclosure. A second side of the carton has a cutout portion defining a window. A handle extends from the first side. The carton preferably has a corrugated construction. 
         [0016]    A better understanding will be obtained from the following detailed description of the presently preferred, albeit illustrative, embodiments of the adhesive dispenser invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of an adhesive dispenser system with portions of the system being removed; 
           [0018]      FIG. 2  is an exploded view of a portion of the adhesive dispenser system of  FIG. 1 ; 
           [0019]      FIG. 3  is an enlarged fragmentary perspective view of a portion of the adhesive dispenser system of  FIG. 1 , viewed generally from the rear; 
           [0020]      FIG. 4  is an enlarged fragmentary perspective view, partly exploded and partly in schematic, illustrating a portion of the adhesive dispenser system of  FIG. 1 ; 
           [0021]      FIG. 5  is a schematic view illustrating the operation of an adhesive delivery system; 
           [0022]      FIG. 6  is a frontal perspective view of a packaging module which may be employed in the adhesive dispenser; 
           [0023]      FIG. 7  is a fragmentary perspective view of the packaging module of  FIG. 6  from a second side thereof; and 
           [0024]      FIG. 8  is a plan view of a pre-assembled form for an outer portion of the packaging module of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0025]    An adhesive dispenser system is adapted for use with for moisture sensitive materials, such as two-part polyurethane adhesives used in the construction trades. For example, one commonly used chemical component for adhesive for which the system has particular applicability is methylene diphenyl diisocyanate (MDI)—which is moisture sensitive. The adhesive dispenser system, designated generally as  10 , employs at least one packaging module  11  which protects the pre-mixed components from moisture in the atmosphere, prevents the escape of volatile materials and ultimately substantially prevents, if not eliminates, crystallization in the pump, mixing components, conduits, delivery hoses and fixtures. The adhesive dispenser system  10  is used to facilitate the mixing and dispensing of moisture sensitive materials, as well as to ensure material integrity during shipping, pre-use storage and post-use storage. 
         [0026]    With reference to  FIGS. 6-8 , in one preferred embodiment, a packaging module unit  11  comprises an outer container body or carton  12  and an inner bag member or bladder  20  (only partially illustrated). The inner bladder  20  is made of a water-impermeable flexible sheet material and has a spout  22  which is closed by a threaded cap  24 . As described below, the cap  24  is valved and adapted for efficient connection with a conduit. The spout  20  may be truncated and have a reinforced ridged neck portion. The bladder is filled with one part of the adhesive (not illustrated) and, upon filling, substantially occupies the interior volume of the carton  12  and preferably closely conforms to the interior sides of the carton. The carton  12  is preferably a corrugated rigid or semi-rigid, box-like structure manufactured from a die cut panel  13  such as illustrated in  FIG. 8 . The carton supports and protects the bladder  20  and its contents and also facilitates transportation and handling. 
         [0027]    For storage and transportation purposes, the carton  12  includes a top side  14  to which a handle  16  is affixed. The carton also has an opening  16  in side  14  to provide access to the spout  22  and cap  24  of the bladder. Another side of the carton includes an elongated window  18  which extends to a short distance from the top surface to allow inspection of the contents of the bladder and, in particular, the amount of remaining material. 
         [0028]    The inner bladder  20  receives and contains the moisture-sensitive material during shipping, use and pre- and post-use storage. Preferably, the inner bladder  20  is manufactured from a durable plastic material which is translucent or transparent to allow the contents to be viewed. It is preferred that the inner bladder  20  has a raised reinforced spout  22  equipped for threading with interior threads of the cap  24 . The spout  22  has sidewalls extending upwardly to form a ridged structure to an opening for the bladder. The cap  24  is pre-installed shortly after the adhesive components are placed in the bladder  20 . 
         [0029]    In another preferred embodiment, the spout  22  is self-sealing either by use of a twist-cap, valve, or similar closing or sealing means. According to this embodiment, the spout  22  is repeatedly sealable so that the material therein remains in substantially the same condition as it was upon the first opening or first use of the material inside the bladder  20 . 
         [0030]    In another embodiment, the carton  12  has an inside surface (not illustrated) that is covered or coated with a substantially water impermeable membrane so that the inside surface forms a substantially continuous liner member. According to this embodiment, the spout is sealed with the liner member so that any material contained within is substantially protected from moisture. Alternatively, the spout and the membrane defining the liner are manufactured as a one-piece unit. 
         [0031]    With reference to  FIGS. 1 and 2 , the packaging module  11  is especially adapted for incorporation and use in conjunction with a mobile dispenser cart  50 . The cart  50  includes a tubular support frame  52  which mounts the various dispenser components and component materials and provides mobility and efficient organization for the dispenser system. The frame  52  includes a pair of laterally spaced, angler tubular supports  53  and  55  which upwardly terminate in handlebars  54  and  56  and, at a lower rear location, receive an axle  58  for a pair of wheels  60 . The handlebars angle rearwardly at an upper rear location and include a pair of grips  64  to facilitate manual movement of the cart. A pair of laterally spaced angled tubular supports  66  and  68  extend forwardly from a medial location of the handlebars and extend downwardly to terminate at a pair of support legs  67  and  69 . The legs provide a stable support for the cart and allow the cart to be pivotally tilted for movement of the cart in hand-truck fashion whereby the wheels  60  support the cart and facilitate rolling movement. 
         [0032]    A lateral, generally horizontal tray  70  is mounted to the support arms. The tray has a circumferential upstanding retaining flange  72 . The tray has openings  74  ( FIG. 2 ) as well as a pair of spaced centrally located upright position guides  76 . A pair of forward laterally spaced slots  78  are also formed in the retention flange  72 . 
         [0033]    With additional reference to  FIG. 3 , a shelf  80  extends between the supports  53  and  55  at a lower forward position adjacent the joining with supports  66  and  68  to form a generally horizontally disposed support platform. A dual inline geroter pump assembly  90  is mounted to the lower support platform. A pump unit  92  has an inlet  93  and an outlet  94 . Pump unit  96  (mounted in reverse relationship to pump unit  92 ) has an inlet  97  and an outlet  98 . Inlets  93  and  97  communicate and connect via connectors with respective transparent conduits  103  and  107  which communicate with the packaging units  11  so that each part of the adhesive is generally supplied under gravity to the respective pump unit. Outlet fittings  94  and  98  connect with the dispensing/delivery hoses  104  and  108 . The pump units are driven by an electric motor  100  which is controlled by a control module  101  mounted to the rear of the tray. A skirt  102  may be mounted to the front of supports  66  and  68  to generally enclose and protect the various conduits and the pump assembly  90 . 
         [0034]    With additional reference to  FIG. 5 , the tray  70  is dimensioned and configured for receiving respective cartons  11  for the first and second parts of the adhesive. With additional reference to  FIG. 4 , the cartons are configured for usage and connection by the cap  24  which has a projecting male fitting  26  and an intermediate poppet valve  28 . The carton is then inverted so that the top side  14  rests on the tray. The carton is positioned so that the projecting male fitting  26  is received in the tray opening  74  or alignable therewith. The window  18  of the carton preferably essentially aligns with a slot  78  of the tray. An upstanding guide  76  engages one side of the carton to facilitate proper positioning. The same process is repeated for the carton  11  of the other part (for a two part adhesive). 
         [0035]    An inverted U-shaped retention bar  118  is then mounted over the top of the tray and each module  11  to secure them in position. For applications where only one part is moisture sensitive, only one packaging module  11  may be employed. 
         [0036]    Conduits  103  and  107  respectively extend from each inlet  93  and  97  and at an opposite end mount via a hose clamp  111  a female fitting  120 . Fitting  120  couples with the cap fitting  26  to provide an efficient snap fit connection and open the poppet valve  28  for providing a flow connection from the container bladder to the conduit without exposure to the atmosphere. The fittings which provide for the connection may be similar to that disclosed in U.S. Pat. No. 5,911,403, the disclosure which is incorporated herein by reference. 
         [0037]    Hoses  104  and  108  connect with a mixing nozzle  110 . In one embodiment the hoses  104  and  108  are each approximately  30  feet in length. Each of the cartons may thus be connected to the pump assembly and ultimately the dispensing hoses  104  and  108  and the mixing gun assembly  110  without exposure to the atmosphere (and disconnected from the packaging module contents). The dispensing hoses  104  and  108  extend from the pump outlets  94  and  98  to provide a delivery conduit for delivery of the adhesive parts to the mixer  112 . The hoses each preferably have lever operated valve  114  at the input openings to the mixer  112 . Upon mixture of the constituent two parts, the adhesive is forced under pressure through a dispensing fixture or nozzle, such as representative wand  116  which includes a helical output path. 
         [0038]    A bracket  130  may traverse at an upper location between the supports  53  and  55  to provide a retaining support for coiling the hoses  104  and  108  and/or power cords. The control module  101  including a switch is mounted at the rear of the tray to provide an accessible control unit for operating the pump assembly  90 . 
         [0039]    It should be appreciated that in the event it is necessary to replace one of the components for the adhesive, replacement is relatively efficiently accomplished by disengaging the snap fit connectors  26 ,  120  which, due to the poppet valve nature, does not expose the adhesive components to the atmosphere, and replacing the carton  11  with another suitable carton  11  as previously described. The pump assembly may be powered, in some instances by a gas engine (not illustrated).