Case sealer with integrated hot melt dispensing system

Abstract

A case sealing system comprising an integrated hot melt processing, dispensing and application system whereby the bottom and the top of a filled box are both substantially simultaneously sealed with a hot melt adhesive.

1 . A case sealer comprising a frame having a longitudinal axis that includes an entrance conveyor for moving boxes entering the case sealer along the axis, a pair of longitudinal spaced-apart, lateral belt drives located to receive boxes from the entrance conveyor and move them into and out of a hot melt dispensing platform, said hot melt dispensing platform comprising a floor that is open in the center, the center being flanked by a pair of peripherally located angled floor regions that allows the major flaps of the folded box to drop in order to receive hot melt adhesive, and an integrally connected hot melt dispensing system comprising a plurality of hot melt dispensing nozzles, said nozzles being located both above and below the hot melt dispensing platform. 
   
   
       2 . The case sealer of  claim 1  wherein the areas of angled floor have about a 15° downward angle from horizontal. 
   
   
       3 . The case sealer of  claim 1  comprising a first pair of nozzles above the sealing platform for applying hot melt adhesive to the outside surface of each of the closed minor flaps of the top of the box and a second pair of nozzles located below the sealing platform for applying hot melt adhesive to the outside surface of the closed minor flaps of the bottom of the box. 
   
   
       4 . The case sealer of  claim 1  comprising a first pair of nozzles above the sealing platform for applying hot melt adhesive to the outside surface of each of the open major flaps of the top of the box and a second pair of nozzles located below the sealing platform for applying hot melt adhesive to the outside surface of the open major flaps of the bottom of the box. 
   
   
       5 . The case sealer of  claim 1  wherein the integrally connected hot melt dispensing system comprises a hot melt adhesive, a melt tank having a interior cavity adapted to receive said adhesive, and an automatic dispensing unit integrally connected to the melt tank. 
   
   
       6 . The case sealer of  claim 5  wherein the hot melt dispensing system is programmed to operate at temperatures of about 250° F. or lower. 
   
   
       7 . The case sealer of  claim 6  wherein the hot melt dispensing system is programmed to operate at temperatures of about 200° F. or lower. 
   
   
       8 . The case sealer of  claim 5  wherein the heating chamber of the hot melt dispensing system is connected to a dispensing pump. 
   
   
       9 . The case sealer of  claim 10  wherein said means for transporting said molten adhesive is a heated hose. 
   
   
       10 . The case sealer of  claim 1  wherein the hot melt dispensing system comprises an adhesive inlet valve for introducing solid adhesive into the melt tank. 
   
   
       11 . The case sealer of  claim 1  wherein the hot melt dispensing system comprises an adhesive inlet valve for introducing solid adhesive into the automatic feed chamber. 
   
   
       12 . A case sealer comprising an integrated hot melt dispensing system connected to said case sealer comprising an automatic dispensing unit for maintaining a supply of said adhesive in its solid form, a supply passage connected to said dispensing unit for supplying said adhesive to the interior cavity of said melt tank, a supply port in communication with the interior cavity of the melt tank and connected to the supply passage, and a nozzle for dispensing molten hot melt adhesive. 
   
   
       13 . A packaging method comprising constructing the box, closing but not sealing shut the bottom of the box, filling the box with a material to be packaged, moving the filled boxes into an area of a box sealer comprising a pair of spaced-apart lateral drive belts and hot melt nozzles, moving the box via the drive belt through a region in which a hot melt dispensing system applies adhesive to the bottom and top flaps, and closing the flaps whereby the bottom and top ends of the box become sealed. 
   
   
       14 . The method of  claim 13  where the hot melt adhesives is substantially simultaneously applied to the top and bottom flaps. 
   
   
       15 . The method of  claim 14  where the adhesive is substantially simultaneously applied to the top of the box on the outside surface of the minor flaps and to the bottom of the case on the outside surface of the minor flaps. 
   
   
       16 . The method of  claim 15  where the adhesive is a low application temperature hot melt adhesive. 
   
   
       17 . The method of  claim 16  wherein the hot melt dispensing system applies the adhesive at temperature of about 250° F. or lower. 
   
   
       18 . The method of  claim 17  wherein the hot melt dispensing system applies the adhesive at temperature of about 200° F. or lower. 
   
   
       19 . The method of  claim 16  herein the hot melt adhesive comprises a polymer selected from the group consisting of amorphous polyolefins, ethylene-containing polymers and rubbery block copolymers, ethylene/vinyl acetate copolymer, isotactic or atactic polypropylene, styrene-butadiene, styrene-isoprene, styrene-ethylene-butylene A-B-A or A-B-A-B block copolymers, ethylene n-butyl acrylate, ethylene vinyl acetate, ethylene vinyl acetate, tactic polypropylene and mixtures thereof. 
   
   
       20 . The method of  claim 19  wherein the hot melt adhesive further comprise a tackifying resins, oils plasticizers, waxes and additives.