FOLDABLE CARTON ABLE TO COLLAPSE FROM AN ERECTED CONDITION

Abstract: A collapsible carton which is formed from a single cardboard blank which when formed from the blank is capable of being folded between a folded flat condition and an erect condition whereby when in the erect condition the carton has a floor (11) and four side panels (12, 13, 14 and 15) to define a generally rectangular prismatic shaped space, wherein the floor panel is formed of a single panel and the junction between the floor and each of the side panels is defined by a closed fold line therebetween, a pair of opposed first side panels (12 and 13) having a pair of diagonal fold lines (21 and 22), extending from the junction between the sides of the floor and the sides of the respective first side panel and converging to terminate at a transverse central axis of the first side panel said diagonals being substantially perpendicular to each other.

Description: TITLE: "Foldable Carton" FOLDABLE CARTON ABLE TO COLLAPSE FROM AN ERECTED CONDITION This invention relates to collapsible packaging such as cartons and the like which are generally formed from cardboard blanks whereby the blanks are folded to form the carton. BACKGROUND ART The cartons to which the invention relates are used in a wide variety of circumstances and one particular example of the application of the cartons relates to the forms of packaging used with take-away food items. It is a common characteristic of such cartons that they are not capable of accommodating liquid contents without the utilisation of a supplementary containment means. As a result, in the event of any spillage within the carton the liquid contents of the carton will leak and can create an undesirable circumstance for customers. In the past, attempts have been made to provide cartons which can to some degree overcome this problem. One example of such a carton is disclosed in US patent specification 4471904 which provides a carton whereby the floor is held in a raised position from the lower limit of the carton. However, in order for the carton to be foldable there is no closed junction between the floor panel and the end and side panels. As a result, there is still the likelihood of leakage therebetween. A further example comprises that which is disclosed in US patent specification 2430755. However, the carton disclosed in that specification is not one that which is capable of being folded and providing a closed junction between the floor and the side panels. It is desirable to provide a carton which when assembled from a blank can be folded to lie in a substantially flat condition and which can be readily unfolded into an erect condition whereby when in the erect condition no further action or DISCLOSURE OF THE INVENTION Accordingly the invention resides in a collapsible carton which is formed from a single cardboard blank which when formed from the blank is capable of being folded between a folded flat condition and an erect condition whereby when in the erect condition the carton has a floor and four side panels to define a generally rectangular prismatic shaped space, wherein the floor panel is formed of a single panel and the junction between the floor and each of the side panels is defined by a closed fold line therebetween, a pair of opposed first side panels having a pair of diagonal fold lines extending from the junction between the sides of the floor and the sides of the respective first side panel and converging to terminate at a transverse central axis of the first side panel said diagonals being substantially perpendicular to each other. According to a preferred feature of the invention the termination of the diagonals defines the height of the side panels, said diagonal fold lines being adapted to fold inwardly with respect to the space to cause the pair of opposed second side panels to fold inwardly to lie adjacent the floor panel. According to a preferred feature of the invention the side panels have a height greater than the termination of the diagonals wherein the floor is provided with a first central fold line which is substantially centrally located and which extends between the first side panels and is adapted to permit the floor to fold inwardly into the space about the first central fold line while the diagonal fold lines fold inwardly, said first side panels being provided with a second central fold line extending centrally from the floor to the opposed edge of the first side panel. According to a preferred feature of the invention at least one of the side panels accommodates at least one top panel which is foldable to be capable of overlying the space. According to a preferred feature of the invention the carton is formed from a blank where the side panels are each hingedly supported from the edge of the floor through a fold line. According to a preferred feature of the above feature the adjacent sides of adjacent side panels are interconnected by a web having an edge which is substantially at 45° to the adjacent edges of the adjacent side panels and which has a further diagonal fold line extending from the junction of the adjacent side panels which bisects the angle therebetween. According to a preferred feature of the invention the second side panels are hingedly supported from the floor and the first side panels are hingedly supported from the second side panels. According to a further preferred feature of the previous feature one first side panel is supported from one of the second side panels and the other first side panel is supported from the other second side panel. According to an alternative preferred feature of the previous feature each second side panel supports a portion of a first side panel whereby the portions of the first side panels co-operate to define the first panels when the blank is folded to an erect condition. According to each preferred feature of the invention at least one of a pair of edges of the blanks which are to become interengaged when the carton is formed are provided with glue flaps. The invention will be more fully understood in the light of the following description of several specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS The description is made with reference to the accompanying drawings of which; Figure 1 is a plan view of a blank according to the first embodiment; Figure 2 is an isometric view of a partially folded blank according to the first embodiment; Figure 3 is an isometric view of an erected carton formed from the blank of the first embodiment; Figure 4 is an isometric view of a folded carton formed of a blank according to the first embodiment; Figure 5 is a plan view of a blank according to the second embodiment; Figure 6 is an isometric view of an erected carton formed from a blank of the second embodiment; Figure 7 is an isometric view of a folded carton formed from a blank of the second embodiment; Figure 8 is a plan view of a blank according to the third embodiment; Figure 9 is an isometπc view of a erected carton formed using the blank of the third embodiment; Figure 10 is an isometric view of a folded carton formed from the blank of the third embodiment; Figure 11 is a plan view of a blank according to the fourth embodiment; Figure 12 is an isometric view of an erected carton formed from a blank according to the fourth embodiment; Figure 13 is an isometric view of a folded carton formed from a blank according to the fourth embodiment; Figure 14 is a plan view of a blank according to the fifth embodiment; Figure 15 is an isometπc view of an erected carton formed from a blank according to the fifth embodiment; Figure 16 is an isometric of a folded carton formed from a blank according to the fifth embodiment; Figure 17 is a plan view of a blank according to the sixth embodiment; Figure 18 is an isometric view of an erected carton formed from a blank according to the sixth embodiment; Figure 19 is an isometric view of a folded carton formed from a blank according to the sixth embodiment; Figure 20 is a plan view of a blank according to the seventh embodiment; Figure 21 is an isometπc view of a erected carton formed from a blank according to the seventh embodiment; Figure 22 is an isometric view of a folded carton formed from a blank according to the seventh embodiment; Figure 23 is a plan view of a blank according to the eighth embodiment; Figure 24 is an isometπc view of an erected carton formed from a blank according to the eighth embodiment; Figure 25 is an isometric view of a folded carton formed from a blank according to the eighth embodiment; Figure 26 is a plan view of a blank according to the ninth embodiment; and Figures 27a to 27g illustrate the assembly of a carton according to the ninth embodiment from the blank shown at Figure26. BEST MODES FOR CARRYING OUT THE INVENTION Each of the embodiments are directed to cartons which are formed from cardboard blanks and which when formed can be readily folded into a substantially flat condition and can be erected from the folded flat condition to provide a carton defining a generally rectangular prismatic shaped space whereby the junctions between the floor panel and the side panels and end panels and the junctions between the end panels and the side panels are closed and are resistant to the leakage of liquid contents. If desired the internal face of the carton may be lined with a suitable lining such as greaseproof paper or the like which will further resist the flow of liquid materials through the body of the carton. The first embodiment as shown at Figures 1 , 2, 3 and 4 comprises a carton which is formed of a blank shown at Figure 1 where the carton has a floor panel 11 , two end panels 12 and 13 and two side panels 14 and 15 where each of the end panels 12 and 13 and side panels 14 and 15 are provided with an outer extension 16, 17, 18 and 19 respectively which when the carton is erected combine to provide the closure for the carton. Each of the end panels 12 and 13 and the side panels 14 and 15 are formed integrally with the floor panel 11 and are connected by a fold line whereby they can be folded to be substantially perpendicular to the floor panel 11 which will bring their adjacent edges into abutment with each other. The abutting edges of the side panels 14 and 15 and their extension panels 18 and 19 are provided with glue flaps 20 which are adapted to be able to adhere to the abutting faces of the respective side panels 14 to sealingly close the junction between the end panels and the side panels 14. Each of the end panels 12 and 13 are provided with a pair of diagonal fold lines 21 and 22 which extend from the junction between the adjacent edges of the end panel and the adjacent side panel and terminate at the central axis of the end panel whereby the diagonal fold lines 21 and 22 are perpendicular to each other. In addition in the case of the first embodiment the floor panel 11 is provided with a first central fold line 23 which is centrally located and extends between the end panels 12 and 13 while each of the end panels 12 and 13 and the respective extensions 16 and 17 are formed with a second central fold line which is co-linear with the central fold line of the floor panel 11. In addition each of the extension panels 16 and 17 on the end panels 12 and 13 are provided with a pair of second diagonal fold lines 24 and 25 which are parallel to the first diagonal fold lines 21 and 22. In the formation of the carton from the blank, the side panels and end panels are folded to be substantially perpendicular to the floor panel 11 which brings the glue flaps 20 into face to face engagement with the respective end panels 12 and 13 and their extension panels 16 and 17. The flaps 20 are then bonded to the respective end panels and the extension panels to define a substantially cubic carton as shown at Figure 3. Figure 2 illustrates the carton partially erected. Once erected the carton defines a liquid tight space whereby the folded junctions between the floor panel and each of the side panels and end panel is substantially continuous and is closed and the junctions between the side panels and the end panels are also continuous and sealed. Furthermore, the carton can be readily folded to a substantially flat condition as shown at Figure 4. This is effected by causing the first central fold line 23 of the floor panel 11 to fold inwardly while causing the first diagonal fold lines 21 and 22 of each of the end panels to fold inwardly. This action brings the side panels into face to face engagement with each other with the folded floor panel and end panels located therebetween. When the carton is in the erected condition the carton can be closed by causing the second diagonal fold lines to fold inwardly which serves to bring the extensions 18 and 19 on the side panels 14 and 15 towards each other to fold over the space accommodated by the carton. In the case of the second embodiment as shown at Figures 5, 6 and 7 the blank is of generally similar form to that of the first embodiment with the exception that the end panels and side panels 112, 113, 114 and 115 are of a reduced height and have a height corresponding to the spacing of the junction of the first diagonal fold lines 121 and 122 from the floor panel 111. In addition the floor panel 11 is not provided with a central fold line and similarly the end panels 112 and 113 are not provided with a central fold line. Furthermore, one side panel 114 supports a closure panel 118 which serves to lie across the space defined above the floor panel 11 when it is desired to close the carton. In folding the erected carton and as shown at Figure 7, the first diagonal fold lines 121 and 122 are caused to fold inwardly which serves to bring the side panels 114 and 115 into face to face engagement with the floor panel 11. Again a carton is provided which can be readily folded between an erected and collapsed condition but which provides a carton in which the junctions between the floor panel and the side panels and end panels is capable of retaining liquid contents. In the case of the third embodiment as shown at Figures 8, 9 and 10 the carton is of a generally similar form to that of the first embodiment with the exception that in the case of the end panels 212 and 213 the edges are not provided with glue flaps but rather the edges of the end panels are interconnected with the adjacent edges of the adjacent side panels by a web element 227 which has an outer edge which is at substantially 45° to the edges of the end panel and side panel. In addition the webs 227 are each provided with a third diagonal fold line 228 which extends from the junction between the adjacent edges of the adjacent end panel and side panel where the third diagonal fold line 228 bisects the angle between the adjacent end panel and side panel. In folding the blank to form the erected carton as shown in Figure 9 the web 227 is folded about the junction between the respective end panel and side panel and the third diagonal fold line 228 is caused to fold inwardly such that the web is folded and lies adjacent the respective side wall to be bonded thereto. In the case of the fourth embodiment as shown at Figures 11 , 12 and 13 this is of a generally similar form to the second embodiment in that the height of the end panels and side panels corresponds to the spacing of the termination of the first diagonal fold lines 321 and 322 from the floor panel 311. In addition the floor panel 311 and the end panels 312 and 313 are not provided with a central fold line. In the case of the third embodiment one end panel 312 is formed to be integrally formed as part of one side panel 314 while the other end panel 313 is formed to be an integral part of the other side panel 315 whereby on the carton being erected the base of the end panels is in abutment with the floor panel 311 and is provided with a glue flap 320 which will be bonded to the floor panel 311. The fifth embodiment as shown at Figures 14, 15 and 16 is of generally similar form to the fourth embodiment in terms of the location of the end panels in relation to the side panels, however, the end panels and side panels are each provided with an extension 416, 417, 418 and 419 respectively and a first central fold line 423 is provided in the floor panel and a second central fold line 424 is provided in each of the end panels. When the carton has been formed from the blank as shown at figure 15 it will be folded and collapsed in a similar manner to that of the first embodiment of Figures 1 , 2, 3 and 4. The sixth embodiment as shown at Figures 17, 18 and 19 comprises a carton which is formed from a blank where each of the side panels supports a portion of each end panel which when the carton is erected combine to form the end panels. The erected carton of the sixth embodiment folds in a similar manner to that of the second embodiment of Figures 5, 6 and 7. The seventh embodiment of Figures 20, 21 and 22 is of a similar form to that of the sixth embodiment with the exception that each of the end panels and side panels are provided with an extension panel 616, 617, 618 and 619 and the bottom panel is provided with a first central fold line 623 and the resultant end panels are each provided with a second central fold line 624 and whereby the erected carton will collapse in a similar manner to that of the first embodiment of Figures 1 , 2, 3 and 4. The eighth embodiment of Figures 23, 24 and 25 is of a similar form to that of the seventh embodiment with the exception that the adjacent edges of the portions of the end panels 712a, 712b, 713a and 713b and the floor panel 711 are interconnected by web members 727 having an edge which is at 45 degrees to the respective edges of the portion of the respective end panel and the floor panel. Each web 727 is provided with a third diagonal fold line 728 extending from the junction between the respective portion of the end panel and the floor panel and which bisects the angle therebetween. In formation of the carton the web panels 727 are folded inwardly as a result of the third diagonal fold line folding inwardly into the interior of the carton whereby on the carton being erected the folded web 727 lies against the end panel and is glued thereto. The erected panel folds in a similar manner to that of the first embodiment of Figures 1 , 2, 3 and 4. The ninth embodiment of Figures 26 and 27a to 27g is of very similar form to the first embodiment as shown at Figures 1 to 4 and the same reference numerals have been used in respect of corresponding features. The only difference is that the ninth embodiment includes a transverse fold line 30 formed in each of the end panels 12 and 13 and which extends from the point of intersection of the diagonal fold lines 21 and 22 to one side of each end panel 12 and 13. The transverse fold line facilitates the folding of the blank to form a carton. The steps involved in forming the carton are illustrated at Figures 27a to 27g. The first step involves folding the glue flaps 20 provided on the side panel 15 and extension panel 19 which are remote from the transverse fold line 30 inwardly such that they overlie the respective panel 15 and 19 respectively as shown at Figure 27a. The second step involves folding each end panel 12 and 13 about the first diagonal folds line 21 and 22 and simultaneously folding the end panel 12 and 13 about the transverse fold line 30 to cause the outer portion of each end panel to underlie the portion of the end panel defined by the first diagonals 21 and 22 as shown at Figure 27b. The third step involves folding the glue flaps 20 provided on the side panel 14 and extension panel 18 which are proximate the transverse fold line 30, inwardly such that they overlie the respective panel 14 and 18 respectively as shown at Figure 27c. The fourth step involves folding each end panel 12 and 13 about the junction with the floor panel 11 such that the end panels 12 and 13 in their entirety overlie the floor panel 11 as shown at Figure 27d. The fifth step involves folding the side panel 15 which is remote from the transverse fold line 30 about the junction with the floor panel 11 after the exposed faces of the glue flaps 20 of that side panel and it's extension panel 19 have been rendered such that they will adhere to the opposed faces of the end panels 12 and 13 as shown at Figure 27e. The sixth step involves folding the blank as folded to that point in time about the central fold line 23 in the floor panel 11 as shown at figure 27f. The final step involves folding the side panel 14 which is proximate the transverse fold line 30 about the junction with the floor panel 11 after the exposed faces of the glue flaps 20 of that side panel and it's extension panel 18 have been rendered such that they will adhere to the opposed faces of the end panels 12 and 13 as shown at Figure 27g. The resultant folded blank will take the form as shown at Figure 4 in relation to the first embodiment and can be opened to form a carton as shown at Figure 3 in relation to the first embodiment. The above folding sequence in relation to the ninth embodiment is given by way of example only. The folding sequence can vary depending upon the nature of the folding facilities that are available Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. It should be appreciated that the scope of the present invention need not be limited to the particular scope of the embodiments described above.

Claims: CLAIMS The claims defining the invention are as follows: 1. A collapsible carton which is formed from a single cardboard blank which when formed from the blank is capable of being folded between a folded flat condition and an erect condition whereby when in the erect condition the carton has a floor and four side panels to define a generally rectangular prismatic shaped space, wherein the floor panel is formed of a single panel and the junction between the floor and each of the side panels is defined by a closed fold line therebetween, a pair of opposed first side panels having a pair of diagonal fold lines extending from the junction between the sides of the floor and the sides of the respective first side panel and converging to terminate at a transverse central axis of the first side panel said diagonals being substantially perpendicular to each other. 2. A collapsible carton as claimed at claim 1 wherein the termination of the diagonals defines the height of the side panels, said diagonal fold lines being adapted to fold inwardly with respect to the space to cause the pair of opposed second side panels to fold inwardly to lie adjacent the floor panel. 3. A collapsible carton as claimed at claim 1 wherein the side panels have a height greater than the termination of the diagonals wherein the floor is provided with a first central fold line which is substantially centrally located and which extends between the first side panels and is adapted to permit the floor to fold inwardly into the space about the first central fold line while the diagonal fold lines fold inwardly, said first side panels being provided with a second central fold line extending centrally from the floor to the opposed edge of the first side panel. 4. A collapsible carton as claimed at claim 1 or 2 or 3 wherein at least one of the side panels accommodates at least one top panel which is foldable to be capable of overlying the space. 5. A collapsible carton as claimed at any one of the preceding claims wherein the carton is formed from a blank where the side panels are each hingedly supported from the edge of the floor through a fold line. 6. A collapsible carton as claimed at any one of the preceding claims wherein the adjacent sides of adjacent side panels are interconnected by a web having an edge which is substantially at 45° to the adjacent edges of the adjacent side panels and which has a further diagonal fold line extending from the junction of the adjacent side panels which bisects the angle therebetween. 7. A collapsible carton as claimed at any one claims 1 to 4 wherein the second side panels are hingedly supported from the floor and the first side panels are hingedly supported from the second side panels. 8. A collapsible carton as claimed at claim 7 wherein one first side panel is supported from one of the second side panels and the other first side panel is supported from the other second side panel. 9. A collapsible carton as claimed at claim 7 wherein each second side panel supports a portion of a first side panel whereby the portions of the first side panels co-operate to define the first panels when the blank is folded to an erect condition. 10. A collapsible carton as claimed at any one of the preceding claims wherein at least one of a pair of edges of the blanks which are to become interengaged when the carton is formed are provided with glue flaps. 11. A collapsible carton substantially as herein described with reference to the accompanying drawings.

Inventors: BELL MATTHEW COLIN, BELL, MATTHEW, COLIN
Applicants: BELL MATTHEW COLIN, BELL, MATTHEW, COLIN
Application year: 1999
Main classification: B65D5
IPC codes: B65D5