Background
Disposable paperboard cartons have long been commercially available for storing, transporting and selling both powder and granular type materials. For decades, these cartons contained metal pour spouts which were hinged to allow easy opening of the carton for initial use and easy closing of the carton for storage.
In an effort to reduce the costs of manufacture and the complexity of carton making machinery, fabricators have sought ways to replace the metal pour spout with one made of paperboard.
A number of containers have been designed wherein the pour spout and reclosure tab are constructed of paperboard. One such design is illustrated in U.S. Pat. No. 3,226,003 to Hickin. This patent discloses a carton having a vertically extending spout located in its narrow side wall together with a reclosable tab. Reclosure is effected by pushing the lower end of the tab into a discharge opening formed in an underlying sidewall. This reclosure feature was an improvement over prior containers. However, by cutting the discharge opening from the lateral edge of the carton blank, the integrity of the carton during manufacture may be affected, and the stability to vary the size of the discharge opening for varying product size without necessitating a change in the closure flap is not possible. The closure flap pivots about a horizontal hinge line and lifting of the tab is in an upward vertical direction.
U.S. Pat. No. 3,563,447 issued to Katzenmeyer discloses a carton having a horizontal pull tab with a vertical pour spout. The tear panel pivots about a vertical fold line. However, the discharge opening is provided by limiting the length of the underlying panel making it impossible to vary the size of the spout opening without significantly altering the closure flap as well.
Summary of the Invention
A carton constructed according to the teachings of this invention is made from conventional paperboard stock which may be coated on one or both sides with low density polyethylene (LDPE). A one piece blank is used in order to minimize cost of manufacture and the reclosure tab is an integral part of the paperboard blank.
The box configuration comprises four side panels, a bottom and a top. An inside panel having an extension panel is also provided. The bottom of the carton consists of two dust flaps and two end panels. The top of the carton also consists of two dust flaps and two end panels. The inside panel has a precut pour spout opening and is bonded to the inside of one of the side panels. The side panel which is attached to the inside panel contains a closure tab which is defined by a combination of reverse cut score lines in a horizontal direction, a cut edge on one vertical side and a hinged score line on the other which is aligned with the fold line between adjacent side panels. These reverse cut score lines allow ply separation to occur along the pour spout edges and defines the pour spout opening in the outer panel. As described above, the closure tab maybe hinged about one of the cartons fold lines and allows for maximum opening of the pour spout area independent of the actual size of the pour spout opening.
A T shaped pour spout opening allows for easy secure reclosure of the closure tab. Additionally, product sifting after reclosure is resisted due to the tight frictional engagement of the edges of the opening tab against the ends of the T shaped cut out.
The configuration of the pour spout allows great flexibility in the type of product packaged and stored in the carton. If the contents are course, the pour spout opening is enlarged to accommodate the large size granules. If the contained product is fine, the pour spout size is reduced so as to limit the rate at which the carton content are dispensed which in each instance, the size and configuration of the closure tab remains constant. This allows the carton to be inexpensively and readily adapted for any size product.
The Drawings
FIG. 1 is an outside plan view of a paperboard carton blank which has been cut and scored in accordance with this invention.
FIG. 2 is a perspective view of a carton which is constructed from the carton blank of FIG. 1 and illustrates the position of the closure tab prior to initial opening and use.
FIG. 3 is a plan view of panel 12 showing the closure tab in its fully extended position.
FIG. 4 is a plan view of panel 12 showing the closure tab in its fully reclosed position.
Detailed Description
The carton blank illustrated in FIG. 1 is cut from an integral conventional paperboard blank. As would be obvious to one skilled in the art, score lines 29, 30, 31 and 32 became fold lines for the carton and delineate panels 10, 11, 12, 13, and inside panel 14. Panels 10 and 11 become the main panels of the carton. Panels 12 and 13 become the side panels. The top flaps are 16, 17, 20 and 21. When folded inward, these flaps become the top of the box with the outermost flap 16 being glued to inner flap 17. Similarly, flaps 18, 19, 22, and 23 become the bottom of the container with the outermost flap 18 being glued to inner flap 19. Perforation line 15A allows for easy folding of panel extension 15 which extends from the inside panel 14.
Inside panel 14 is attached and adhesively bonded to the inside of panel 12. Side panel 12 has a closure tab 44 which is defined by edge cut 45, cut lines 44C, reverse cut score lines 25, 26 and hinge line 29. Reverse cut score lines 26 are formed on the outer side panel 12 while reverse cut score lines 25 are formed on the inner surface of side panel 12. Inside panel 14 has a cutout 27 which is T shaped and an outside cut score area 28. The closure tab 44 also crease score line 33 for ease of bending when reclosing the tab.
During manufacture of the carton, adhesive is applied to the glue area 46 and the full length of inside panel 14 between the cut out 27 and cut scored area 28. The inside panel 14 is folded on crease score line 32 and the main panel 10 is folded on crease score line 30. This type of gluing is known to the industry as edge gluing.
The area of the closure tab 44 between the crease line 33 and the edge cut 45 is bonded to the cut score area 28 of inside panel 14. When the closure tab 44 is grasped for initial opening, the cut score area 28 will ply separate beginning at a point of weakness at a leading edge cut score of area 28. To open the container, the user grasps the point of initial opening at edge cut 45 and tears back to the hinge line 29 or a crease line which may be formed in the panel 12. The region between reverse cut score lines 25 and 26 will ply separate at the point where they intersect and extend to the hinge line 29. The hinge line 29 then becomes the hinge line for the closure tab 44. To close the opening, formed by the cutout closure 27 tab 44 is folded on score line 33 and an extending end therof is inserted into the T slot of cutout 27.
The closure tab 44 is shown in its open and fully extended or open position in FIG. 3. The area between reverse cut lines 25 and 26 shows ply separation over the full length of the cut score line 26. The ply separation along both edges of the closure tab 44 is symmetrical. Also shown is ply separation in the cut score area 28.
FIG. 4 illustrates a view of the container with the closure tab 44 inserted in the T slot of cutout 27. The closure tab 44 may be hinged along the score line 29. Prior to reclosing the carton, the end of the closure tab is folded inward at crease score line 33. After bending the closure tab end inward, it is inserted into the T slot of cutout 27. The pour spout is securely and tightly reclosed for storage pending further use. The disclosed carton can therefore be sealed tight enough to resist shifting and can be easily reopened for further dispensing.
The size of the cutout 27 can be enlarged or reduced to accommodate both large and small type particles. To reduce the size of the opening, cut line 43 is moved in the direction of the T slot. By controlling the location of the cut line 43, the pour rate of the contained product may be easily controlled to meet the requirements of the type of product being dispensed. As mentioned previously, by varying the size of cutout 27, the carton may be readily and inexpensively adapted to dispense products of various sizes. The size of cutout 27 can be easily change thereby altering the effective size of the dispensing opening while the size and configuration of the closure tab 44 remains constant. It should be noted however that the hinge line of the closure tab 44 need not coincide with fold line 29.
It should be recognized that while various embodiments in accordance with the present invention have been described, the present invention will be susceptible to numberous other changes and modifications which will become apparent to those skilled in the art from the foregoing disclosure. Therefore, the present invention should not be considered to be limited to the details shown and described herein, but encompasses all such changes and modifications as are within the scope of the appended claims.