Clamping band   

BACKGROUND OF THE INVENTION

The present invention relates to a clamping band for use in retaining two parts of substantially circular form in mutually fixed relationship. The invention more particularly, although not exclusively relates to a clamping band for retaining a lid or cover in sealed manner across the opening of a storage drum.

Industry-standard clamping bands are of metal and are designed for fitment to drums of specific size—typically known as 15 to 55 gallon drums. The known bands comprise a single (approx.) 360° open-ended loop of specified length. The loop has a hook arrangement at one end and an over-centre locking mechanism comprising a lever and catch at the other end. The locking mechanism is a permanent fixture of the band. In use, the loop is fitted about the periphery of a circular lid and mating peripheral flange at the opening of a cylindrical drum, whereupon the locking catch is engaged with the hook and the handle is pivoted beyond an over-centre position to a resting locked position.

Such known clamping bands are manufactured in different sizes to suit standard sized drums. Where a drum or lid is out of specification, the only method of changing the ring diameter is by changing the mould tool conditions in an attempt to grow the product in size. This is a time-consuming and possibly dangerous procedure. The single open-ended band design is reasonably well suited to fabrication in metal, but the bands are substantially inelastic which exacerbates the problem of fitment to out-of-spec drums/lids. In any event, the WPO (World Packaging Organisation) has implemented a policy to phase out steel clamping bands and steel lids in about five years for open top drums.

Plastics clamping bands have been proposed such as for example as disclosed in U.S. Pat. No. 4,678,216. However such designs do not lend themselves to cost-effective manufacture due to physical limitations of known moulding techniques. Furthermore, such bands are not designed for fitment to drums of various alternative dimension or out-of-spec drums or lids. The method of manufacture is labour-intensive and requires robots to remove the product from a purpose-designed mould tool. Also, bands for each different sized lid require their own designated moulding die.

The single open-ended band design is also not well suited for stacking and compact shipment and storage. Furthermore, if one end portion of the loop or the locking mechanism for example is damaged, then the whole band must be repaired or replaced.

It is an object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages and/or more generally to provide an improved clamping band.

DISCLOSURE OF THE INVENTION

There is disclosed herein a clamping band, comprising: a first band segment; a second band segment detachably secured to the first band segment; and a clamp for maintaining the secured first and second band segments in a closed loop configuration.

Preferably, the clamping band further comprises a connection interface between the first and second band segments which allows for adjustment of the length of the loop.

Preferably, the connection interface comprises a receptacle forming part of the first band segment and a tongue forming part of the second band segment which is configured for insertion into the receptacle.

Preferably, the first and second band segments are of channel section—comprising a floor and a pair of walls extending from the floor, and the each band segment further comprises one or more ribs extending from the floor to an inner surface of one, the other or both walls, the ribs being adapted to interact with a lid and/or opening of a vessel covered by the lid to urge the lid against the opening as the clamping band is tightened peripherally thereabout.

Preferably, the first and second band segments are of channel section, and the receptacle is of channel section—comprising a floor and a pair of spaced walls extending therefrom, and the receptacle includes a plurality of spaced aligned apertures and the tongue comprises a barb configured to be received by a selected one of the apertures.

Preferably, the apertures are in a wall of the receptacle channel section, and the tongue is of channel section with the barb extending outwardly from a wall thereof.

Preferably, one of the channel walls of the receptacle comprises a return extending toward the receptacle channel floor, and the tongue is of channel section comprising a pair of opposed walls—one of which is received by the return.

Preferably, the clamp comprises a lever attached pivotally and detachably to both the first and second band segmants.

Preferably, the first band segment comprises a fork having mutually facing lugs, and wherein the lever comprises a pair of slots into each of which a respective lug is slidably received.

Preferably, each lug has a widened head, and each slot includes a widened assembly aperture through which a respective one of the heads passes as the lever is attached to the first band segment.

Preferably, the second band segment comprises a hook and the lever comprises a hinge pin for pivotal interaction with the hook.

Preferably, the second band segment comprises a pair of said hooks in laterally aligned mutual association, and the hinge pin interacts pivotally with both said hooks.

Preferably, the lever is channel-shaped to receive a portion of the second band segment therein.

Preferably, the second band segment comprises an eyelet and the lever includes an internal recess flanked by the slots so that when the eyelet is located in or adjacent to the recess the eyelet is laterally aligned with the slots to enable passage of a split pin through the eyelet and slots.

Preferably, each band segment is of moulded plastics material.

Preferably, the lever is of moulded plastics material.

Preferably, the plastics material is fibre-reinforced.

The present clamping band will advantageously address the issue of variation in lid/cover size for open top 15 to 55 gallon drums. The clamping band can also be adjusted to fit various lid sizes utilising the same clamping band.

Furthermore, the components of the clamping band can be disassembled and purchased individually for replacement.

The new design also enables the mould tools/dies to be of multi cavity type enabling the moulded parts to be ejected from the dies in a conventional manner. This design enables the use of alternative reinforced plastic resins to be use for various applications of increased strength and durability.

The present invention aims to provide the industry not only a price reduction, but the versatility of a single clamping band to suit a range of lids and/or adjustability to suit out-of-spec lids and/or drums.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings, wherein:

FIG. 1 is a schematic perspective illustration of a clamping band;

FIG. 2 is a schematic plan illustration of the clamping band in an open, segment-detached configuration;

FIG. 3 is a schematic plan illustration of one clamping band segment;

FIG. 4 is a schematic perspective illustration of the clamping band segment of FIG. 3;

FIG. 5 is a schematic plan illustration of the other clamping band segment;

FIG. 6 is a schematic perspective illustration of the clamping band segment of FIG. 5;

FIG. 7 is a schematic perspective illustration of the locking lever; and

FIG. 8 is a schematic inverted perspective illustration of the locking lever.

FIG. 9 is a schematic side view representation of an embodiment of a clamping band when engaged with a vessel and a lid.

In the accompanying drawings there is depicted schematically a clamping band 10 comprising a pair of substantially semicircular clamping band segments 11 and 12. For the purpose of description, these will be referred to hereinafter as a first clamping band segment 11 and a second clamping band segment 12. Each clamping band segment is formed as a plastics injection moulding of high strength, high impact resistance material such as polyethylene. The clamping band can also includes a locking lever 13 which would typically be formed of the same or similar type of plastics material. Both clamping band segments and the locking lever might be fibre-reinforced—typically with glass fibre or other high tensile strength fibre such as but not limited to metallic fibre and carbon fibre.

Each clamping band segment 11, 12 is moulded using conventional injection moulding techniques and is of channel-shaped cross-section. This cross-section is generally C-shaped or U-shaped, although it might alternatively be V-shaped.

The first and second clamping band segments 11 and 12 are mutually interconnected by means of a connector receptacle 14 moulded integrally with the second segment 11 and into which a tongue 17 of the first segment is received. The arrangement of the preferred embodiment enables the segments to be interconnected in one of three positions so as to provide an overall circumference suitable for application to various different sized drums. To this end, the connector receptacle 14, which is also of channel-shaped cross-section, is provided with three aligned apertures 19 in one of its side walls. The tongue 17 which slides into the connector receptacle 14—again of channel-shaped cross-section—is provided with a ramped barb 18 at the outer surface of one of its side walls. A degree of resilient movement of the wall section from which the barb 18 extends is assisted by a small cut out in the floor of the tongue as shown in FIG. 4 directly alongside the barb. When the tongue 17 is inserted into the connector receptacle 14, the barb 18 snap-engages into the first, second or third recesses depending upon choice once in place, it is not possible to withdraw the tongue unless a sharp implement is pressed through the aperture 19 in which the barb is lodged. As illustrated in FIG. 6, the connector receptacle 14 includes at one of its side walls a return feature 28 which extends back toward the floor of the channel section to surround one wall of the tongue 17 when the tongue is inserted into the connector receptacle 14. This is the wall of the tongue 17 which is opposite to that from which the barb 18 extends. This feature provides great stability and strength to the interconnection of the two clamping band segments.

At a position diametrically opposite the above features is a locking lever 13, associated fork 15, a pair of hooks 21 and an eyelet 16.

The fork 15 is moulded integrally with the first band segment 11 and comprises a pair of fingers each having extending inwardly therefrom a lug 19a. Each lug 19a has an enlarged head as shown.

The hooks 21 are moulded integrally at an end portion of the second band segment 12. There are two such hooks 21 laterally offset from one another. Situated slightly along the second band segment 12 is an eyelet 16 which extends outwardly therefrom at a laterally central position.

The locking lever 13 is also channel-shaped and is dimensioned such that the clamping band segment 12 fits within it. The lever 13 includes a pair of side walls into each of which there is provided a longitudinal slot 22 terminating with a widening 25 each serving as an assembly aperture through which the head of the respective fork lug 19a passes when the lever 13 is attached thereto. The lever 13 has an open end across which there extends a hinge pin 23 comprising a pair of shaft segments 24 flanking a strengthening web 27. The shaft segments 24 are each to be snap-engaged by the hooks 21 so that the lever 13 pivots about the hinge pin 23 when connected to the second band segment 12.

The lever 13 includes internal reinforcing ribs and a recess 26 formed in one or more of those ribs. When the lever 13 is closed down upon the second band segment 12, the eyelet 16 is received within or alongside the recess(es) 26 so that a split pin or the like can be passed laterally through the opposed slots 22 and through the eyelet to maintain the lever 13 in its closed position.

Each band segment 11, 12 includes a number of wedges 20 extending from the channel floor to one or both of the channel walls.

In use, the band segments are interconnected as described earlier to a circumference suitable for the size of drum and cover to be sealed thereon. The hinge pin 23 of lever 13 is snap-engaged with the hooks 21 and the fork is spread apart to clear the lever 13 so that the heads of the fork lugs 19a can be passed through the assembly apertures 25 to be held in place behind the respective slots 22. The clamping band is now of over-sized diameter sufficient to be placed about the periphery of the drum opening lip and fitted cover. Once in place, the lever 13 is pivoted toward its closed position whereupon lugs 19a slide along the slots 22 to a rest position at the opposite end of the slots 22. The lever 13 is then pivoted past an over-centre resistance whereupon tension in the fork 15 biases the lever 13 into a closed position against the band segment 12. During the lever-closing operation, the wedges 20 in each clamping band segment bear upon the opening lip/flange of the drum from beneath and the lid from above to force the lid down upon the opening to form a seal. The more force that is applied to the lever—the higher the clamping and sealing force.

Referring to FIG. 9, there is depicted is a schematic side view representation of an embodiment of a clamping band 30, which is engaged with a vessel 50 and a lid 40, so as to secure the lid 40 to the vessel 50 in a manner as described in reference to FIGS. 1 to 8.

At a designated angle the lever can be removed for replacement if damaged. Each half of the ring can be detached for ease of storage and individual replacement. This is a superior solution than replacing the entire clamping band as is the case with known prior art clamping bands.

It should be appreciated that modifications and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention. For example, three or more clamping band segments could be connected end-to-end and a ratchet type mechanism or even a cable tie style of interconnection could be provided instead of those features specifically exemplified at 14 and 19 for example. Alternatively, a different number of apertures 19 (e.g. 2, 4, or more) could be provided and apertures the same or similar to those depicted could be provided in both the floor and side wall portions of the connector receptacle 14. It should further be appreciated that alternative uses of the clamping band herein are envisaged. Moreover, the clamping band could be suited for use as an equatorial band securing two like halves of a pressure vessel to one another.