AU687244B2 - A hinge for a collapsible container - Google Patents

Description

This invention relates to improvements in and to collapsible or folding containers and in particular to an improved hinge mechanism for a collapsible storage container used for storing fluid material.

The containers subject of this application are of the type comprising a substantially rectangular support base having a horizontal floor, a pair of opposed end panels or gates hinged about respective horizontal axes so that they can fold inwardly into a collapsed condition on top of the base, and a pair of opposed side panels also hinged about respective horizontal axes for folding inwardly into a collapsed condition on top of the base. The arrangement is such that the end and side panels can be folded inwardly to a position where they lie approximately flat one on top of the other p. ~with adjacent panels overlying one another. Each of the panels normally comprises a metal peripheral frame and a solid panel infill secured to the frame.

One application for such folding containers is the storage ~and transport of fluid products. Obviously, it is necessary to provide a fluid tight liner which is located within the erected container. In most instances, a bladder or substantially cubic container formed from plastic sheet material is used. An outlet or spout is provided at the base of the bladder for the purposes of filling or emptying the bladder.

With known collapsible liquid storage containers where the end and side panels are arranged to fold inwardly to allow collapsing of the container when empty, clearances or gaps can be found between adjacent side and end panels and also between the bottom edges of the panels and the support base to which the panels are hingedly connected, when the container is erected. When using fluid bladders it has been found that the plastic sheet material of the bladder will tend to force itself or "creep" into the gaps between the panels. If this occurs, movement of the container, or general wear and tear, can result in the bladder rupturing.

In order to overcome this problem, it has been common in the past to make use of flexible sealing strips on one of the panels so that it abuts against the other thereby sealing the gap. However, such sealing strips are time consuming in respect of their installation, and are subject to wear and dislodgement resulting in ineffective sealing of the clearances and in turn damage to the bladders. No effective solution is known for sealing the gaps which normally exist between the bottom edges of the panels and the support base.

Accordingly, it is an object of this invention to obviate at least to some degree the abovedescribed problem.

o It is a further object of this invention to provide an improved hinge arrangement for each of the folding panels which allows the panel to be connected to the container base without any gap or clearance therebetween.

Broadly according to this invention therefore, there is 2. provided an improved hinge connection between an end or side S panel and the support base of a collapsible storage container of the type hereinbefore described, wherein the panel o. comprises a metal peripheral frame and a planar infill sheet of polymeric material characterised in that said planar infill sheet comprises a region of reduced thickness which forms a hinge line extending across said sheet so as to form first and second sheet portions which can rotate relative to one another, said first sheet portion being secured along its length to said base, said second portion being secured to the frame of the panel, whereby the panel may hinge inwardly over said base support.

By having the hinge formed as an integral part of the panel infill sheet and the bottom flap portion of the polymeric sheet secured along its length to the base of container, gaps between the panel bottom edge and the base are avoided gaps which would otherwise allow ingress of the sheet material used for the bladder.

Preferably, the support base is provided with a polymeric liner, such as a removable tray, which is used for supporting the base of the bladder. With this invention, it is possible to abut the hinged corner portion of the panel infill sheet against the upper edge of the tray so that there is virtually no gap between the two members and thereby avoid possible pinching of the bladder.

Preferably, the hinge is formed on the inwardly facing surface of the panel sheet, and therefore readily allows the end or side panel to fold inwardly so as to lie approximately S flat on top of the support base.

Preferably, the hinge may be cut using a milling or routing attachment, or may also be formed by using a heat roller.

Preferably, a half round cutter is used, and a channel or groove is formed in one side of the sheet which has a width approximately two to three times greater than the depth of the cut.

Preferably, the polymeric material used is a polypropylene which can withstand repeated hinging operations without deterioration of the material at the hinge line. The removal of the material enables the hinge to close to at least 900 in one direction from its original planar position, or to rotate a full 1800 in the opposite direction. In respect of a side or end panel, movement through an angle of approximately 900 is all that is required.

Preferably, all four side panels/gates of the container are hinged to the support base with a hinge arrangement according to this invention.

Preferably, each of the side and end panel/gates has its bottom flap portion connected to the upper surface of a respective skirting wall which extends along one of the sides of the support base. The skirting walls can be of different heights whereby the panels are supported at different heights above the floor of the base.

In another aspect of the invention, the hinge means as described above may also be used for an upper portion of the front or rear gate which folds outwardly through 1800 so that it can lie flat against the outside surface of the lower portion of the gate. This arrangement provides ready access to the interior of the container. In this instance, the hinge is formed and folded back against itself so that the total range of movement is approximately 1800. Clearly, the orientation of the hinge is important to obtain this range of rotation.

As stated previously, there is also a similar problem where the side and end panels abut along juxtaposed vertical faces.

Clearly, unless the panels abut tightly against one another, 16.. gaps or clearances will exist.

In the past, beading or flexible strips have been used to cover the vertical joins, but again with the hinge lines, this method of covering the clearance is unsatisfactory.

Another difficulty is the locking mechanism used to hold the side and end panels in their elevated or erect positions. It is known to use some form of retracting pin on one panel which locates within an aperture in a retractable tongue carried by an adjacent panel. This particular locking mechanism is described in our earlier Australian Patent No.

628746. Such a locking arrangement works quite satisfactorily with sealing strips which may be used, however it is very difficult to ensure that the various panels abut tightly against one another. Very small manufacturing tolerances must be observed in order to arrange the location of the tongue and locking pin so that each of the side panels is pulled tightly against the end panels.

Therefore, it is a further object of this invention to provide a means of ensuring that the side panels abut securely against each of the end panels, thereby preventing 4 any significant clearance between the end and side panels when the container is erected.

According to a further aspect of this invention, there is provided a tongue and pin locking mechanism similar to that described in our Australian Patent No 628746, further comprising a clamping mechanism operatively associated with the slidable tongue and which acts to pull the locking tongue against the pin so that an inner surface portion of one of the panels is drawn firmly against the vertical end face of the adjacent panel.

S" Preferably, with the latch pin released, the clamping mechanism is designed to allow the locking tongue to fully 5• withdraw or retract by means of the tongue sliding inwardly with respect to the panel.

Preferably, the mechanism comprises a rotatable lever arm, a cam member fast with the arm, the lever arm and cam being rotatable through 90' to provide approximately 2mm of retraction movement of the tongue which will normally meet the requirements. In this example, the cam member and lever arm may be pivotally attached to the frame of the respective S panel, with the cam being arranged to act against an engagement member which is fixed with respect to the frame and also against an end of the tongue (or latch bar) such that rotation of the cam pushes the end of the tongue away from the fixed member.

In this manner, sufficient clamping force is achieved to draw the side panel against the end panel.

Preferably, polymeric sheet material is used to line the entire inside surface of each of the panels, and may be arranged so that it extends slightly past the sides or edges of each of the panels so that the clamping action will act against a resilient polymeric surface rather than a hard steel surface of a panel frame member. This prevents any minor damage such as either warping of the panels, or damage to the edges resulting in a clearance or gap sufficient to allow ingress of the bladder material.

In order for the invention to be fully understood, a preferred embodiment will now be described with reference to the accompanying drawings. However, it should be realised that the scope of this invention is not to be confined or restricted to the precise details of this embodiment. In the drawings: S Fig 1 shows a partial side view of a support base and one of the side panels of a folding liquid storage container made in accordance with this invention; S" Fig 2 shows a side view of a latching mechanism which incorporates a clamping device (shown in the unclamped position) in order to firmly clamp together adjacent end and 0 side panels of a storage container in their erect positions; while Fig 3 is a fragmentary perspective view of the mechanism shown in Fig 2, with the clamping device rotated to its clamping position.

Referring to Fig 1, a lower corner portion only of a folding container 10 is illustrated. The container 10 comprises a rectangular support base 11 to which are connected front and rear gates (not shown) and a pair of side panels 12 (one only being shown) which can pivot between collapsed and erect positions. The side panel 12 folds about a hinge line 13 so that it can fold to its collapsed position on top of the support base 11.

In accordance with prior art designs, the support base 11 is provided with angle section stub corner posts 15 and skirting wall members 16 which extend along all four sides of the base 6 11 and which support the panels 12 and/or end gates. The skirtings 16 will normally be of different heights so as to allow the panels and gates to lie flat one on top of the other on the base 11.

In this embodiment, a unitary polymeric tray 17 is used to line the floor of the support base 11 and the inside faces of the skirting members 16. The upper edge of the tray 17 lies contiguous with the hinge line 13.

The side panel 12 comprises a unitary planar infill sheet of polymeric material which is divided by the hinge line 13 .fl..e into a first panel infill portion 21 and a second attachment portion 22 which forms an extension flap extending along the bottom of the panel 12. The hinge line 13 is formed by oooo cutting a half round section into one side of the polymeric sheet 20. The first portion 21 of the polymeric sheet 20 is attached eg by rivets, to the inside surfaces of the peripheral frame members 25 of the side panel 12, while the second flap portion 22 is secured, eg by rivets, at spaced intervals along its length to the upper wall of the skirting 16 of the support base 11. In this embodiment, the frame members 25 and skirts 16 are formed of tubular steel.

go 2.9: The underside surface of the sheet portion 22 abuts against the upper edge of the tray 17 and results in minimal clearance between the two components. This prevents sheet material of the bladder from becoming trapped along the hinge line.

The attachment of the flap portion 22 to the skirting 16 of the support base 11 hingedly secures the side panel 12 to the support base 11 for folding movement between fully erect and collapsed positions. As seen in the exploded view of the hinge line 13, the formation of a trough 27 allows the polymeric sheet 20 to bend at the hinge line 13 so that the first and second portions 21, 22, when the panel is erect, are at an angle of 900 with respect to one another. The side 7 panel 12 is then able to hinge inwardly over the support base 11 in order to collapse the container In this embodiment, the width of sheet portion 22 is approximately equal to the width of the skirting 16.

Although not illustrated, both side panels 12 and both end panels of the folding container 10 are constructed similar to that illustrated in Fig 1, with the flap portions of their panel sheets being fixed along their lengths to respective skirting walls 16 on the support base 11.

to*.e0 Referring to Figs 2 and 3 of the drawings, there is shown a o. latching mechanism 30 which is used to secure adjacent side and end panels of a collapsible storage container in their c erected positions. The latching mechanism 30 comprises a S" slidable locking bar or tongue 31 having a latch pin engaging aperture 32 near its distal end and which is designed to slide back and forth. When in its fully retracted position, the tongue 31 does not protrude past the outside edge of the side panel frame member 25. In this embodiment, the tongue 31 r eo ~locates through a slotted opening 34 formed in the frame member The tongue 31 is attached to a shaft 35 which is slidably located in a fixed guide 36. The guide 36 is secured to a mounting plate 37 fixed to the side panel frame members On the end of shaft 35 is secured an abutment member 38, eg a washer, and pivotally mounted between the guide 36 and member 38 is a lever arm 42 which is provided with cam In order to engage the latching mechanism 30, the tongue 31 is extended and a locking pin 41 which is moveably mounted on the end panel (not shown) near an upper corner thereof, is engaged through the aperture 32.

With the pin 41 engaged, rotation of the cammed lever arm 42 to its clamping position will cause the member 38 to move 8 away from the guide 36 by a distance sufficient to cause the tongue 31 to be drawn inwardly against the latch pin 41 and in turn pull the pin 41 bodily inwards so that -the end panel is firmly clamped against the side panel 12. This effectively eliminates any clearance between the adjacent end and side panels.

When the pin is dis-engaged from the aperture 24, the tongue 23 is free to slide inwardly to a position where its distal edge lies in-board of the outer edge of frame member In this embodiment, the polymeric liner sheet of the end r coo panel is dimensioned so that it overlaps peripheral frame members 25 whereby, when the panels are erect and the lever "IS arm 42 engaged, the inside face of the end panel sheet abuts against the outside wall surface of the frame member 25 of the side panel 12. Since the liner sheet is compressible, there will be some slight deformation which ensures minimal iee clearance between the adjacent panels.

As will be seen from the above description, the invention provides a folding container that presents virtually no clearance or gaps which might otherwise cause damage to the plastic sheet material of the liquid containing bladder. The invention is a significant improvement over previously known folding containers used for this purpose.

Claims (11)

1. 2. The improved container according to claim 1, wherein the hinge region is formed by a groove or channel in one side of the sheet and which has a width greater than the maximum depth of the channel or groove.
2. 3. The improved container according to claim 1 or claim 2, wherein the or each said panel is supported on top of a respective skirting member extending along one of the sides or margins of the support base, the or each said panel having its base attachment sheet portion secured by fastener means to an upper horizontal wall of said skirting member.
3. 4. The improved container according to claim 3, wherein the width of the base attachment sheet portion ijs approximately equal to the width of the upper wall of said skirting member.
4. 5. The improved container according to claim 3 and claim 4, wherein each skirting member is formed of tubular metal.
5. 6. The improved container according to any one of the preceding claims wherein said peripheral frame members are formed of tubular metal. 999999
6. 7. The improved container according to any one of the preceding claims further comprising a plastics liner tray fitted to the support base, wherein the upper edge of the 3. ~tray is contiguous with (or nearly so) the underside surface of said base attachment sheet portion in the vicinity of the hinge region.
7. 8. The improved container according to any one of the o preceding claims wherein the hinge connection between the sheet portions is configured to allow relative rotation through at least 900.
8. 9. The improved container according to any one of the preceding claims further comprising latching means for releasably latching together adjacent panels of the container at the upper corners thereof, when in an erected condition, said latching means comprising: a latch pin movably mounted on one of said adjacent panels near an upper corner thereof; a locking tongue slidably mounted at the upper corner of the other of said adjacent panels for sliding to and fro movement between extended and retracted positions, said tongue being provided with a latch pin receiving hole adjacent its distal end, arranged so that when said tongue is in its extended position, the latch pin can locate through the hole to thereby lock the adjacent panels together; and 11 a clamping mechanism operatively associated with said slidable tongue and which acts to pull tongue against the latch pin so that an inner surface portion of one of the adjacent panels is drawn firmly against an outer end face of the other of said adjacent panels. The improved container according to claim 9, wherein said clamping mechanism comprises a pivotal lever arm attached to the other of said adjacent panels for swinging movement between clamping and release positions about an axis at right angles to the plane of the panel, a cam member on the lever arm, and a fixed engagement member secured to said other panel and located adjacent said cam member, arranged so that upon movement of the lever arm to its clamping position, the cam member acts against said engagement member and also against an abutment surface on the locking tongue such that S" rotation of the cam pushes the inner end of the locking tongue away from the fixed engagement member to thereby effect the clamping action of the locking tongue against the 260 latch pin. S 11. The improved container according to claim 10, wherein said abutment is formed by a washer carried by the locking ~tongue adjacent its inner end, the washer being located on the side of the lever arm opposite to that of the fixed engagement member.
9. 12. The improved container according to either claim 10 and claim 11, wherein said locking tongue comprises an elongate rod which is guided for slidable movement in a passageway extending through said fixed engagement member.
10. 13. The improved container according to any one of claims 9 to 12, wherein said locking tongue, when the latch pin is in its release position, is able to retract to a position where its leading end lies in-board of the panel frame.
11. 14. The improved container according to any one of claims 9 to 13, wherein said locking tongue, when in its extended position, projects through aligned slotted openings formed in said metal peripheral frame members of said adjacent panels. An improved collapsible container substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings. Dated this 25th day of October, 1995. REES OPERATIONS PTY LTD By its Patent Attorneys MADDERNS @0e f I I ABSTRACT The invention provides an improved hinge arrangement for an end or side panel of a collapsible liquid storage container wherein the panel (12) is hinged for inward folding movement to a collapsed condition on top of the support base (11) of the container The panel (12) comprises a metal peripheral frame (25) and a polymeric panel infill sheet which is formed with a region of reduced thickness so as to form a hinge line which extends across the width of the sheet The sheet (20) is thereby formed with a panel infill sheet portion (21) which is secured to the peripheral frame and a second sheet portion (22) which is secured along its length to the support base with the sheet portions 21) being rotatable relative to one another so as to allow the panel (12) to hinge inwardly over the support base (11). a a a a.