Interlocking Means for Carton Panels

Abstract

A panel interlocking arrangement for securing together a pair of panels ( 28 b, 28 a ). The two panels may form overlapping panels of a paperboard carton. The interlocking arrangement comprises a locking tab ( 60 ) having a heel ( 60 b ) and a toe ( 60 a ). The locking tab is provided adjacent an end ( 40 ) of one ( 28 b ) of the panels and is hinged about its centre to that panel by a pair of divergent fold lines ( 63, 65 ). The interlocking arrangement further comprises one or more locking apertures ( 70 ) formed in the other ( 28 a ) of the panels. The one or more apertures are shaped in complementary fashion to the locking tab. To lock the panels together, the locking tab is inserted into the one or more apertures. The insertion of the locking tab is facilitated by both the heel and toe of the locking tab being pivotal about the divergent fold lines.

1 . A panel interlocking arrangement for securing together first and second panels of a carton, the interlocking arrangement comprising a locking tab formed at least in part in said first panel and one or more locking apertures provided in said second panel for receiving the locking tab, the locking tab comprising a locking heel and a locking toe, wherein the locking tab is hinged to the first panel by a pair of diverging fold lines extending from the locking heel towards the locking toe whereby hinging action between the locking tab and the first panel is predetermined to facilitate the insertion of each of the locking toe and heel into said one or more locking apertures to lock the panels together. 
   
   
       2 . A panel interlocking arrangement according to  claim 1  wherein each of said diverging fold lines terminates at a free edge of the first panel. 
   
   
       3 . (canceled) 
   
   
       4 . A panel interlocking arrangement according to  claim 1  wherein said one or more locking apertures comprises a single locking aperture into which both the locking toe and locking heel are inserted. 
   
   
       5 . A panel interlocking arrangement according to  claim 1  wherein said one or more locking apertures are provided with at least one pair of slits extending outwardly from said one or more locking apertures so that the insertion of the locking tab into said one or more locking apertures is facilitated. 
   
   
       6 . A panel interlocking arrangement according to  claim 1  wherein the locking heel is in part defined by a substantially semi-circular cut line and in part by arcuate end portions, wherein the arcuate end portions terminate at the divergent fold lines respectively. 
   
   
       7 . A panel interlocking arrangement according to  claim 6  wherein said one or more locking apertures have a heel-engaging edge, the heel-engaging edge having a slit extending from each end of said heel engaging edge. 
   
   
       8 . A panel interlocking arrangement according to  claim 7 , wherein the arcuate end portions of the locking heel each abut an edge of a respective one of said heel engaging edge slits when the locking tab is engaged within said one or more locking apertures. 
   
   
       9 . A panel interlocking arrangement according to  claim 1  wherein said one or more locking apertures is in part defined by a toe-engaging edge, said toe-engaging edge having a toe engaging edge slit extending from each end of the toe-engaging edge to facilitate the insertion of the locking toe into said one or more locking apertures. 
   
   
       10 . A panel interlocking arrangement according to  claim 1  wherein the locking toe is shaped such that the locking toe has arcuate shoulder portions and wherein side portions of said one or more locking apertures are shaped similarly to the shoulder portions respectively to promote easy insertion of the locking toe into said one or more locking apertures. 
   
   
       11 . A panel interlocking arrangement according to  claim 9  wherein the second panel is provided with a first hinge line, the first hinge line extending between said toe-engaging edge slits to define a first engagement tab between said toe engaging edge slits. 
   
   
       12 . A panel interlocking arrangement according to  claim 11 , wherein the first engagement tab is hingedly connected to the second panel along said first hinge line to facilitate the insertion and removal of the locking toe into and from said one or more locking apertures. 
   
   
       13 . A panel interlocking arrangement according to  claim 9  wherein the second panel is provided with a side hinge line extending between each side edge of the one or more locking apertures and an adjacent one of the toe engaging edge slits, the side hinge lines defining side engagement tabs which are foldable to encourage the insertion of the locking toe into said one or more locking apertures and which aid the secure engagement of the locking tab within said one or more locking apertures. 
   
   
       14 . A panel interlocking arrangement according to  claim 1  wherein said one or more locking apertures comprises two locking apertures for receiving the locking toe and the locking heel respectively. 
   
   
       15 . A panel interlocking arrangement according to  claim 14  wherein the locking heel is spaced and offset from the locking toe. 
   
   
       16 . A panel interlocking arrangement according to  claim 15  wherein the two locking apertures are disposed in an offset alignment similar to the offset alignment of the locking toe and heel such that the locking toe and heel can be received and held within said two locking apertures to secure the two panels together. 
   
   
       17 . A panel interlocking arrangement according to  claim 15  wherein the locking heel is spaced diagonally from the locking toe such that the centre of the locking heel lies on different vertical and horizontal axes relative to the vertical and horizontal axes upon which the centre of the locking toe lies. 
   
   
       18 . A panel interlocking arrangement according to  claim 14  wherein the locking tab comprises a second locking heel and said one or more locking apertures comprises a third locking aperture for receiving said second locking heel. 
   
   
       19 . A panel interlocking arrangement according to  claim 18  wherein the centre of the second locking heel lies on the same horizontal axis as the first locking heel and wherein the second locking heel is spaced diagonally from the locking toe such that the centre of the second locking heel lies on different vertical and horizontal axes to the axes on which the centre of the locking toe lies. 
   
   
       20 - 21 . (canceled) 
   
   
       22 . A panel interlocking arrangement according  claim 1  wherein the locking toe projects from a free end edge of the first panel. 
   
   
       23 . A carton comprising a series of main panels including first and second panels which are secured together by a panel interlocking arrangement, the interlocking arrangement comprising a locking tab formed at least in part in said first panel and one or more locking apertures provided in said second panel for receiving the locking tab, the locking tab comprising a locking heel and a locking toe,
 wherein the locking tab is hinged to the first panel by a pair of diverging fold lines extending from the locking heel towards the locking toe.