GB2069464A

GB2069464A - Corner members for stckable boxes

Info

Publication number: GB2069464A
Application number: GB8104245A
Authority: GB
Original assignee: METAL CLOSURES THERMOPLASTICS
Current assignee: METAL CLOSURES THERMOPLASTICS
Priority date: 1980-02-14
Filing date: 1981-02-11
Publication date: 1981-08-26
Also published as: AU537825B2; IE810205L; EP0034464A1; IL62088A0; AU6687281A; GR74417B; DE8103922U1; IE50562B1; GB2069464B; IT8167198A0

Description

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SPECIFICATION

Corner joints for forming right-angles between adjacent panels This invention relates to corner joints for forming right angles between pairs of panels and is particularly although not exclusively applicable to corner joints for forming right angles between adjacent side walls of a box formed from a blank sheet or sheets.

U.K. Patent Specification No. 1532317 discloses a joint made of a synthetic plastics material and fitted to a top corner of a cardboard box of rectangular or square shape so that the box may be rendered packable, the joint comprising two mutually perpendicular lateral faces adapted to be placed against the outside of the box, a bearing surface at right angles to the inter-section of the lateral faces for receiving a bottom corner of a corresponding overlying box and a plurality of clamping plates arranged on the inside below the 85 bearing surface spaced from the lateral faces and perpendicular to the bearing surface, with the aid of which the joint may be clamped on to the upright box walls. Such joints rely on the edges of the clamping plates digging into the box walls in order to grip the walls and this arrangement can be unsatisfactory and unreliable particularly if the walls of the box are formed from a relatively hard material such as hardboard or if the walls of the box are not uniform in thickness. A corner joint has 95 also been proposed in which a base has two mutually perpendicular walls to lie against the inner sides of a corner of a box and two resilient tongues on the outer sides of the walls to engage the outer sides of the corner and hold the walls of 100 the joint against the corner. With that arrangement however it is difficult to separate the tongues from the walls to assemble the joint on the corner.

This invention provides a corner joint for 105 forming a right angle between a pair of panels of a container comprising a base having two edges extending at right angles to each other to form the base with a right angled apex, two dependent walls extending downwardly from the base adjacent to said two edges of the base respectively for engaging the outer sides of a pair of panels of a container and two resilient tongues depending from the base at locations based inwardly of said two edges of the base respectively to engage the inner sides of the pair of panels of the container, the tongues being accessible from the outer sides of the walls to be pressed manually away from the walls for S5 assembly of the corner joint on a pair of panels of 120 a container and, on release, to engage and hold the panels against said walls.

The invention also provides a corner joint for forming a right angle between a pair of panels comprising a base having two edges extending at right angles to each other to form the base with a right angled apex, two walls depending from the base at right angles to each other and aligned with the right angled edges of the base, two resilient GB 2 069 464 A 1 tongues depending from the base each tongue being located to one side of a respective wall for holding a pair of panels engaged with the two walls, each of which tongues has a projection formed thereon partway down the tongue on the side adjacent a respective wall to engage in a corresponding hole in the respective panel to be engaged by the tongue, each of which pips is formed with an inclined ramp face on the side nearest the bottom end of the tongue to assist in guiding the upper edge of a respective panel over the projection as the joint is located on a panel.

Preferably the resilient tongues are inclined with respect to the base towards the respective walls or the planes in which said walls lie such that, in their relaxed condition, the lower ends of the tongues are closely adjacent the walls or said planes.

The following is a description of some specific embodiments of the invention, reference being made to the accompanying drawings in which:

Figure 1 is a perspective view of an inner corner of a box having side walls connected by a corner joint in accordance with the invention; Figure 2 is a perspective outer view of the corner as shown in Figure 1; Figure 3 is a plan view of the corner joint; Figure 4 is a side view of the joint; Figure 5 is a view on the arrow 5 on Figure 3; Figure 6 is a section on the line 6-6 on Figure 4; and Figures 7 to 9 show further embodiments of the invention.

Sim-pie open topped boxes which are required to be filled and then packed one on top of each other are frequently supplied in a very large number in flat condition and are intended to be assembled as and when required. For example boxes for food and in particularfruit and vegetables are frequently used in this manner. A simple form of box of this type comprises a cardboard blank having a rectangular base and four side walls which are folded up along lines which may be pre-creased and locked together when the box is required for use. Alternatively the box maybe formed in hardboard in which the flat blank comprises a base with the four side walls hinged to the edges of the base. This invention is particularly concerned with a corner joint for locking two adjacent side walls of the box together and for permitting one box to be stacked on anoth - er.

Figures 1 and 2 of the drawings show two side panels 10, 11 of a cardboard or hardboard box which have been folded up from a base as previously described to form a right angle between them and are held together by a corner joint indicated at 12.

The corner joint, which is illustrated in greater detail in Figures 4 to 6, comprise a base 13 having two side edges 14, 15 extending at right angles to each other. Two integral walls 16, 17 lying at right angles to each other depend from the lower face of the base. The upper ends of the walls lie along but are spaced slightly inwardly of the sides 14, 2 of the base. Each wall 16, 17 has a large aperture 18, 19 therein so that the walls are generally U-shaped with two adjacent limbs 16a, 17a, of the U forming an integral apex and two limbs 1 6b, 17b spaced from the apex.

The upper corner portions of the panels 10, 11 lie adjacent the inner sides of the walls 16, 17 and the panels are held against the walls by resilient tongues 20, 21 depending from the base 13 adjacent the inner sides of the walls opposite the apertures 18, 19 therein. In their natural or relaxed condition as manufactured, the resilient tonguii-s are inclined towards the walls 16, 17 so that the free ends of the tongues lie adjacent the apertures in the walls 16, 17. The free ends of the tongues may lie just short of the apertures or in the apertures or may even project slightly through the apertures.

Each tongue has a raised projection 22, 23 on the side thereof adjacent the respective side wall 16, 17 to engage in a hole 24, 25 formed in the respective panel 10, 11 to assist in holding the joint on the panels of the box. The lower side of each projection 22, 23 is formed with a chamber 22a, 23a, to provide a ramp for guiding the upper edge of the respective panel 10, 11 outwardly past the projection as the corner joint is pressed into the panels. Also downwardly extending lugs 26, 27 are formed between the base and the inner sides of the limbs 16b, 17b. The lower ends of the lugs 26, 27 have chamfers formed thereon. The upper edges of the panels 10, 11 are formed with notches 28, 29 in which the lugs engage to assist in locking the panels 10, 11 into the corner joint and prevent them from moving outwardly of the apex of the joint.

The joint can conveniently be assembled on a corner of a box or container by holding the joint between the thumb in the recess 13 or in the base 13 and two fingers extending the apertures 18, 19 105 and bearing on the resilient tongues 20, 2 1. As -the joint is brought into engagement with the comer of the container, pressure is applied to the resilient tongues by the fingers to deflect the tongues inwardly sufficiently to enable the container panels to be received between the tongues 20, 21 and the walls 16, 17 of the joint.

The joint is then pressed downwardly until the base 13 engages the top edges of the container panels as shown in Figures 1 and 2. The projections 22, 23 snap into the apertures 24,25 in the container panels automatically on reaching the apertures and the lugs 26, 27 engage in the notches 28, 29 in the top edges of the panels. 120 Four such corner joints are provided for the four respective corners of the box to lock the pairs of panels at each corner together.

The base 13 at each corner of the box is intended to receive the bottom corner of a further box to be stacked on top. To assist in locating the bottom corner of the further box, the base is formed with an up-standing flange 30 along the sides 14, of the base. Depending on the strength of the material used for the boxes and the weight of goods contained therein, a number of such GB 2 069 464 A 2 boxes can be stacked one upon the other.

Figure 7 of the accompanying drawings showsa joint generally similar to the joint described and illustrated above and like parts have been allotted the same reference numerals. The only difference is that the integral walls 16, 17 are further extended downwardly as indicated at 1 6a and 1 7a and are formed with further cut-outs 32, 33 to reduce the amount of material required for the extension. The length of the downwardly extending integral walls from the base to the bottom edge 34 of the walls is equivalent to the depth of the container on which the joint is to be used so that when the joint is assembled on the container, the bottom edge 34 lies generally flush with the bottom face of the container. Thus when a stack of containers is formed, the bottom faces 34 of the joints of one container rest on the bases 13 of the joints below. The loads in the stack are therefore transmitted through the superimposed corner joints rather than through the containers.

Figures 8 and 9 show an alternative construction in which the side walls 16, 17 are somewhat narrower and are reinforced by a rib 14 extending down the outer apex between the two walls from the base and tapering to nothing at the bottom edges of the walls. The resilient tongues 20, 21 are spaced to one side of the walls 16, 17 and'located inwardly of the walls to provide access to the tongues to deflect the tongues inwardly when assembling the joint on a corner of a container as previously described. In addition the joint has two further downwardly extending walls 36 which are located on the opposite sides of the tongues to the first walls 16, 17 and are spaced still further inwardly of the side edges of the base 13 than the tongues 20 and walls 16, 17. The lower ends of the walls 36, 37 merge together in a downwardly extending angle section leg 38 which is spaced generally inwardly of the walls 16, 17 as best seen in the underplan view of Figure 9. The leg 38 is intended to lie down the inner side of the corner between the two panels on the container to which the joint is to be attached and the length of the leg 38 is such that the bottom face of the leg bears on the bottom of the container. Thus when a stack of containers is built up, the weight of one container is transmitted through the legs of the corner joints of the container to the corner joints of the container below so that the weight of the stack is taken through the corner joints. The resilient tongues may be provided with pips to engage holes in the panels of the container as previously described and, likewise, lugs may be provided on the underside of the base adjacent the walls 16, 17 to engage notches in the upper edges of the panels of the container again as previously described.

The corner joints described above are conveniently manufactured as one-piece injecwn mouldings from a hard plastics such as polypropylene or nylon. It will be appreciated that many modifications may be made to the above described embodiment without departing from the scope of the invention. For example the 3 GB 2 069 464 A 3 projections 22, 23 on the resilient tongues-may be 65 omitted along with the holes in the panels of the box not then required as may be the lugs 26, 27 on the base and the corresponding notches in the 5 panels of the box.

Claims

1. A corner joint for forming aright angle between a pair of panels of a container comprising a base having two edges extending at right angles to each other to form the base with a right angled apex, two dependent walls extending downwardly from the base adjacent to said two edges of the base respectively for engaging the outer sides of a pair of panels of a container and two resilient tongues depending from the base at locations spaced inwardly of said two edges of the base respectively to engage the inner sides of the pair of panels of the container, the tongues being accessible from the outer sides of the walls to be pressed manually away from the walls for assembly of the corner joint on a pair of panels of a container and, on release, to engage and hold the panels against said walls.

2. A corner joint as claimed in claim 1 wherein the resilient tongues are inclined with respect to the base towards the respective walls or the planes in which said walls lie such that, in their relaxed condition, the lower ends of the tongues are closely adjacent the walls or said planes. 30

3. A joint as claimed in claim 1 or claim 2 wherein the edge of the base disposed opposite said right angled apex is formed with a recess to provide a location for holding the base whilst pressure is applied to the resilient tongues when locating the joint on a pair of panels.

4. A joint as claimed in any of claims 1 to 3 wherein the sides of the tongues adjacent the walls are formed with raised projections to engage in corresponding holes in the container panels and assist in holding the joint on the panels.

5. A joint as claimed in claim 4 wherein the base projections are disposed centrally on the resilient tongues.

6. A joint as claimed in any of the preceding claims wherein lugs are provided on the underside 110 of the base adjacent the inner sides of the dependent walls for engaging in notches in the upper edges of the container panels to assist in holding the panels in the joint.

7. A joint as claimed in claim 6 wherein each 115 lug is chamfered at the end remote from the base to assist in locating the lug in the notch in the panels.

8. A joint as claimed in any of the preceding claims wherein the base is formed with upstanding flanges along said two edges thereof to receive and hold a corner of an upper container on the base.

9. A joint as claimed in claim 8 wherein the upstanding flanges meet at the said apex of the 125 base between and are formed integrally with one another.

10. A joint as claimed in any of the preceding claims wherein the two dependent walls converge to an apex and are formed integrally with one another.

11. A joint as claimed in any of the preceding claims wherein each wall is U-shaped to provide two legs connected to the base and an aperture between the legs to provide access to the resilient tongue behind each wall.

12. A joint as claimed in claim 11 wherein the length of the depending walls is equivalent to the external depth of the container on which the joint is to be used so that a number of containers can be stacked one above the other with the lowermost ends of the walls of a joint on the corner of one container resting on the base of a joint of the container below.

13. A joint as claimed in any of claims 1 to 9 wherein each resilient tongue is spaced along the base away from the apex thereof to one side of the respective dependent wall to provide access to the tongue.

14. A joint as claimed in claim 13 wherein the base is formed with a downwardly extending leg joined to the base at locations disposed on the inner sides of said walls or planes containing said walls, the length of the leg behind equivalent to the inside depth of the container on which the joint is to be used so that the lowermost end of the leg bears on the bottom of the container when the joint is assembled on the container.

15. A joint as claimed in claim 14 wherein the leg comprises two further walls extending downwardly from the base on the opposite side of the resilient tongues to the first said walls, the two further walls converging below the resilient tongues and first said walls in an integral downwardly extending angle section element to engage the bottom of the container on which the joint is to be mounted.

16. A corner joint for forming a right angle between a pair of panels comprising a base having two edges extending at right angles to each other to form the base with a right angled apex, two walls depending from the base at right angles to each other and aligned with the right angled edges of the base, two resilient tongues depending from the base each tongue being located to one side of a respective wall for holding a pair of panels engaged with the two walls, each of which tongues has a projection formed thereon partway down the tongue on the side adjacent a respective wall to engage in a corresponding hole in the respective panel to be engaged by the tongue, each of which projections are formed with an inclined ramp face on the side nearest the bottom end of the tongue to assist in guiding the upper edge of a respective panel over the projection as the joint is located on a panel.

17. Ajoint as claimed in claim 16 wherein the two walls are formed with apertures and the tongues are disposed opposite the apertures in the walls.

18. A joint as claimed in claim 16 or claim 17 wherein the tongues are inclined towards the walls at their free ends so that the panels, when located between the tongues and the walls, are 4 GB 2 069 464 A 4 pressed against the walls by the tongues.

19. A corner joint for supporting two adjacent panels of a container substantially as described with reference to and as illustrated in Figures 1 to 5 6.

20. A corner joint substantially as described with reference to and as illustrated in Figure 7 of the accompanying drawings.

21. A corner joint substantially as described with reference to and as illustrated in Figures 8 and 9 of the accompanying drawings.

Printed for Her Majestys Stationery Office by the Courier Press, Leamington Spa, 1981. Published by the Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.

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