DE69200146T2 - Tensioning strap for metal receptacle and receptacle with the strap. - Google Patents

Description

The invention relates to a tensioning strap for metal drums.

The invention also relates to barrels equipped with this tensioning strap.

Among the metal drums currently on the market, a distinction is generally made between drums with bungholes, which consist of a shell closed on both sides by a generally folded or flanged wall, and drums with a total opening, in which one of the walls is removable and is held in place by removable fastening means, such as in particular tensioning straps on the shell.

Due to their robustness, the majority of metal drums with bungholes are regularly reused. There is a considerable industry for the reconditioning of these drums. Depending on the nature of the products transported in these drums, the drums are generally cleaned very thoroughly; it is therefore necessary to have access to their interior. Although this is not a problem for "fully open" drums, for drums with bungholes it is necessary to cut them up, even if they must then be reassembled using an appropriate technique.

Reprocessing also poses a major cost and environmental problem: since certain barrels are used to transport toxic materials or contain substances that are toxic or dangerous to the environment, it is necessary to eliminate the slightest traces of these and to collect the residues in the barrels separately before the barrels are put back into circulation. Such treatment is expensive and there is still no satisfactory alternative. A barrel can be recycled after a After a certain number of reprocessings, the metal may show altered dimensions and a reduction in its mechanical strength; the metal is bent and straightened several times, particularly in the case of folding and unfolding.

The use of a barrel equipped with a removable wall to facilitate cleaning has not generally been adopted; the strength requirements are not as high as for a "fully opening" barrel, certainly because the user does not need to be able to operate the opening mechanism.

US-A-3 603 476 describes a drum in which the edge of the lid and the reinforced wall with a joint therebetween are connected by a tension band without a locking device, which is welded in place and is cut or separated when the drum has to be reconditioned.

Such a barrel is not without disadvantages.

This is because the joint heats up significantly in some areas during the welding/separation process, the weld is quite large, and there is a non-negligible risk of cutting the metal deeper than desired, thus weakening the strength or tightness of the joint.

US-A-1 859 639 describes a container made of frosted wood, provided with a lid and a fixing device for this lid. This container is intended for the transport of foodstuffs, such as butter. The fixing device, the purpose of which is to ensure sufficient tightness so that the butter being transported does not become saturated with the smell of other foodstuffs, is formed by a ring with a C-shaped cross-section. The ends of this ring overlap and one end contains a hinged tab that can be pulled off to separate the lid from the bucket.

GB-A-743 339, which serves as the basis of the preamble of claim 1, describes a removable locking ring for securing a lid to a container. This ring is longer than the circumference of the lid so that an overlap zone can be provided. The ends of this ring, one end of which is larger, are superimposed in such a way that they can be locked in a predetermined closing position. The disadvantage of such a device is that it practically does not allow any readjustment of the band-saving force.

AU-A-79179/75 concerns a tensioning strap in the form of a cut-open ring. One of these ring ends is extended by a tab.

This tab is welded to the other end of the ring. During closing, the inner edge of the ring is folded inwards so that it engages under a spiral that runs around the wall. Opening is carried out by separating the ring ends by removing the tab.

The aim of the invention is therefore to prevent unauthorized persons from easily gaining access to the interior of a barrel.

Another goal is a lid closure device that is easy to open or close when reprocessing the barrels.

Another goal is to provide barrels that are easier to clean and recondition.

Another aim is to obtain a barrel with a removable lid that meets the criteria for barrels with flanged lids.

The invention relates to a tensioning band for a metal barrel. This metal barrel consists of a casing, one end of which is closed by a base and the other end by a lid, the lid being designed along its circumference with a groove-shaped edge that is open downwards and the edge of the casing being designed as a spiral that engages in the groove-shaped edge of the lid and is rolled over outwards, and the tensioning band is designed as a cut-open ring with a central region and two lateral bands with a C-shaped cross-section that is open towards the middle of the ring, and the two lateral bands of the ring press the ring-shaped edge of the lid and the spiral-shaped edge of the container casing against each other; the length of the band corresponds to the circumference of the lid, increased by an overlapping zone of the ends of this band; in this overlap zone, the two ends of the tensioning band overlap, the upper end, called the female end, having a larger cross-section than the other end, called the male end, in such a way that the sections of the two ends connected to one another in the overlap zone fit closely together; the middle edge of the male end of the band is extended by a region or a tongue; the middle part of the female end has a transverse slot in front of the overlap zone so that when the male and female ends overlap, the tongue of the male end can be passed through the transverse slot; the middle part of the female end is provided with two or more transverse ribs projecting towards the outside of the tensioning band, the tongue of the male end being firmly welded to the tip of the last transverse rib that it can reach after the band has been attached and tightened.

According to an advantageous embodiment, the two or more transverse ribs formed on the female end are located in the area of the overlap zone and the tongue extending the male end is guided through the transverse slot to the last of it. accessible transverse rib to which it is welded, to the rear.

According to a further advantageous embodiment, the two or more transverse ribs formed on the female end are located in front of the overlap zone and the transverse slot, and the tongue can be guided through the transverse slot to the last transverse rib that it can reach and is firmly welded to this transverse rib.

Preferably, the central edge of the female end of the band is also extended by a tongue, and on the central part of the male end of the band, in this case, two or more transverse ribs are formed next to the overlap zone, and the tongue extending the female end is firmly welded to the tip of the last accessible transverse rib.

According to an advantageous embodiment, the region with a C-shaped cross section contains a flat ring intended for support on the lid of the barrel, a cylindrical central part intended for enclosing the inner edge of the lid and a frustoconical strip engaging below the spiral forming the upper end of the container shell; the lower strip preferably continues as far as the container shell, with its end extending into a groove-shaped depression extending around the entire circumference of the container shell, the outer diameter of the edge of this end nevertheless being larger than the diameter in the groove base. In this way, the band retains a limited mobility in relation to the wall and its tension can be adjusted as required.

According to a further embodiment, the tensioning band has a semicircular cross-section.

The invention also aims at a metal drum containing a tensioning band as described above.

This drum preferably contains a bag-shaped lining made of flexible plastic material, the edge of which is fixed between the edge of the container wall and the lid and covers the inner surface of the container shell and the base to prevent contact with the contents of the drum.

According to a further preferred embodiment, this barrel contains a closed, bag-shaped lining made of flexible plastic material, suitable for completely preventing contact between the contents of the barrel and the inner walls of the barrel, which is tightly connected to at least one bunghole.

Further details and advantages of the invention are highlighted in the description of the following various embodiments, which refer to drawings in which

Figure 1 is a perspective view with the tensioning band according to the invention detached as a closing device before closing;

Figure 2 is an elevational view of the same strap after closing;

Figure 3 is an elevational view of another form of closure of the tension band;

Figure 4 is a schematic section of a particular embodiment of the barrel equipped with the tensioning band according to the invention;

Figure 5 is a schematic section of another embodiment of a barrel equipped with the tensioning strap according to the invention.

Figure 6 is an enlarged detailed sketch of Figure 4.

Figure 1 shows the ends of the strap 1 before closing. This strap 1 has a C-shaped cross-section, the opening of which is directed towards the inside of the strap. This cross-section is formed by three metal edges: a central, perfectly circular area 2 and two strips 3, 3a which rest respectively on the lid 4 and on the end of the wall 5 of the barrel 6, as can be seen further in Figures 4 and 5.

The total length of the tightening band 1 is slightly greater than the circumference of the lid 4, although when the band 1 is fitted on the barrel 6, its two ends 7 and 8 overlap in an overlap zone 9. One of these ends, called the female end 8, has an extension of the area 10 such that it well covers the other end, called the male end 7, their front sides 2, 3, 3a practically joining together tightly.

The central region 2 of each end 7 and 8 is extended by a tongue 11. The female end 8 has a transverse slot 12 in front of the overlap zone 9 (i.e. opposite the tongue 11).

In this way, as can be seen better in Figure 2, the tongue 11 of the male end is guided through the transverse slot 12 coming from the back of the female end 8 when the two ends 7 and 8 overlap in the overlap zone 9.

Each female end 7, 8 has two transverse ribs 13 and 13a in the central area 2 in front of the overlap zone 9. The ends 7, 8 are connected as shown in Figure 2, their tongues 11 extending beyond these transverse ribs 13. It is therefore easy to weld said tongues 11 onto the last of the transverse ribs they still reach, ie 13a, in order to close the band. A solid band 1 is thus obtained which has the dimensions of the barrel. This strap 1 has no fastening means visible to the user, but it can nevertheless be opened very easily or used in a workshop equipped with the necessary equipment. This strap 1 does not need to be tightened by pulling, as is the case with straps with lever or bolt fastening. In this case, it is necessary to have aids such as a tensioning winch.

From a mechanical point of view, the overlap zone and the folded profiles of the male end 7 and the female end 8, which ensure the tight connection, ensure good overall rigidity of the belt.

Figure 3 shows another embodiment of the closure of the strap 1. The transverse ribs 13, 13a of the female end 8 are here arranged on the overlap zone 9 itself. In this case, the tongue 11 of the male end 7 is bent towards itself in order to be welded onto the last transverse rib 13a that it can reach. This connection offers increased security and even makes it possible, according to an embodiment not shown, to dispense with the tongue 11 that extends the female end 8. It should be noted that the optimal number of transverse ribs 13 can vary and that it is generally between 2 and 4. The tongue 11 is slightly separated from the central region 2 of the tightening strap 1 by its passage to the first transverse rib 13. Thus, there is a sufficient distance between the tongue 11 and the band to allow the insertion of a device or part of a device suitable for severing the tongue 11.

You can also cut the tongue using an angle grinder, for example, without cutting the band itself.

In addition to the above-mentioned advantages, the strap is reusable, which has a positive impact on the cost price of the barrel as a whole. The presence of more than two transverse ribs allows the strap to be effectively reused several times, since the tongue 11 is cut between the transverse rib 13a to which it is welded and the previous transverse rib 13 after each use. It is thus gradually shortened until its length no longer allows it to cover the first transverse rib 13.

Figure 4 shows an interesting embodiment of the inventive clamping band, i.e. a barrel that is easy to clean.

This barrel 6 contains a wall 5 which is delimited by an outwardly bent spiral 14, the other end of this wall 5 is folded with the base 15. The spiral 14 is inserted into a downwardly directed, groove-shaped edge 16 running around the lid 4; the lid 4 with bunghole 17 is firmly connected to the wall 5 by a tensioning band 1 according to the invention, the edges 3 of which press the groove-shaped edge 16 and the spiral 14 together. A sealing cord is inserted into the base of the groove-shaped edge 16, as can be seen better in detail in Figure 6.

The inner surfaces of the wall 5 and the bottom 15 are protected, in order to prevent contact with the contents of the barrel 6, by a sack-shaped lining 18 made of a flexible plastic material, which is fixed by its edge along the connecting surface between the wall 5 and the lid 4, thus in fact being held in place by the tightening band 1.

Such a barrel appears to the user as a completely normal bunghole barrel. However, after emptying it has a considerable advantage, since it is now sufficient to open the clamping band 1, lift off the lid 4 and carefully remove the flexible, sack-shaped lining 18 in order to have a barrel whose inner walls are lined with come into contact with the transported product. The reprocessing of such a drum is considerably facilitated and the undesirable product residues can be easily collected for recovery or their controlled disposal.

Figure 6 also shows an advantageous detail of an embodiment in which the movement of the strip 1 in the vertical direction is limited. The edge of the inner lateral strip (3a) here actually slightly engages in a groove 22, the sides of which form an abutment in the event of vertical displacement of the strip. The stresses exerted on the joint are thus limited and a secure hold of the edge of the lining 18 is ensured.

The use of a tensioning strap 1 is therefore particularly useful here; the accidental opening of the strap 1 by unauthorized third parties or third parties who are not specialized in this field and who, moreover, do not respect environmental protection - which is possible with a strap according to the state of the art - is very unlikely here.

With this clamping band, any mishandling is normally excluded and the only part of the drum that is completely reconditioned at the end of the use cycle is the lid, which therefore represents a considerable benefit for the reconditioning company.

Figure 5 shows another possible embodiment of the invention. In the barrel 19 shown here, the entire inner surfaces are protected by a completely closed, sack-shaped lining 20 placed inside the barrel 19 to prevent contact with the transported product. This lining 20 communicates with the outside via two bungholes 21 fixed to the lid 4.

This lining 20 is inserted more easily the more easily the internal volume remains accessible through the removable cover 4, as the tensioning band 1 according to the invention allows.

Once the lid 4 has been sealed by closing the tightening strap 1, the design of the tightening strap 1 prevents any accidental opening by inexperienced or unauthorized users, as well as any direct access to the flexible lining 20, which could be very dangerous depending on the product being transported.

It is obvious that the clamping band 1 described here can also be used, within the framework of the specific embodiments, as a "safety" band for conventional drums, such as drums for full opening, and that the bottom of a drum can equally well be sealed instead of the lid in order to gain easier access to the internal volume.

The cross-section of the strip 1 can finally be adapted to various cover and connection profiles. In particular, it can be trapezoidal or semicircular.

Claims (10)

1. Tensioning band for metal drums with a casing, one end of which is closed by a base and the other end by a lid, the lid being designed along its circumference with a groove-shaped edge that is open downwards and the edge of the casing being designed as a spiral that protrudes into the groove-shaped edge of the lid and is rolled over outwards, and the tensioning band being designed as a cut-open ring by a central and two lateral bands with a C-shaped cross-section that is open towards the middle of the ring, and the two lateral bands pressing the ring-shaped edge of the lid and the spiral-shaped edge of the container casing against one another, characterized in that - the length of the band (1) is equal to the circumference of the cover (4), increased by the length of an overlap zone (9) of the ends of this band, - the two ends (7, 8) of the tensioning band (1) overlap in this overlap zone (9), the upper end, called the female end (8), having a larger cross-section than the other end, called the male end (7), in such a way that the sections of the two ends connected to one another in the overlap zone (9) fit tightly together, - the middle part (2) of the male end (7) of the tensioning band (1) is extended by an area (11), - the middle part (2) of the female end (8) has a transverse slot (12) in front of the overlapping zone (9), so that when the male (7) and female (8) ends overlap, the area (11) of the male end (7) can be passed through the transverse slot (12), - the middle part (2) of the female end (8) is provided with two or more transverse ribs (13, 13a), wherein the region (11) of the male end (7) can be firmly welded to the tip of the last transverse rib (13a) that can be reached by it. 2. Tensioning strap according to claim 1, characterized in that the two or more transverse ribs (13, 13a) formed on the female end (8) are located in the area of the overlap zone (9) and the area (11) extending the male end (7) can be passed through the transverse slot (12) and bent backwards to the last accessible of these transverse ribs, which can be the last one (13a), and can be firmly welded to it. 3. Tensioning strap according to claim 1, characterized in that the two or more transverse ribs (13, 13a) formed on the female end (8) are located in front of the overlap zone (9) and in front of the transverse slot (12) and the area (11) extending the male end (7) can be passed through the transverse slot (12) to the last accessible of these transverse ribs (13, 13a) and can be firmly welded to this transverse rib. 4. Tensioning strap according to one of the preceding claims, characterized in that the middle part (2) of the female end (8) of the strap (1) is also extended by a region (11) and two or more transverse ribs (13, 13a) are formed on the middle part (2) of the male end (7) of the strap (1) in front of the overlap zone (9), and that the region (11) extending the female end (8) can be firmly welded to the tip of the last accessible of these transverse ribs (13, 13a). 5. Tensioning band according to one of the preceding claims, characterized in that the band (1) is formed by a flat ring (3) provided for support on the lid (4) of the barrel (6, 19), a cylindrical middle part (2) provided for enclosing the bent-over lid edge (16) and a frustoconical strip (3a) extending under the spiral (14) forming the upper end of the container casing (5). 6. Tensioning strap according to one of claims 1 to 4, characterized in that its cross section is semicircular. 7. Tensioning strap according to one of the preceding claims, characterized in that the strip (3a) extending under the spiral (14) forming the upper end of the container casing (5) continues up to the container casing (5), with its end reaching into a groove-shaped recess (22) extending around the entire circumference of the container casing (5), the diameter of which in the groove base is smaller than the inner diameter of the strip (3a). 8. Metal barrel, characterized in that it has a tensioning band (1) according to one of the preceding claims. 9. Metal barrel according to claim 8, characterized in that, in order to prevent contact between the contents of the barrel and the barrel, it has a sack-shaped lining (18) made of flexible plastic material, which is fastened with its edge between the edge of the container shell (5) and the lid (4) and covers the inner surface of the container shell (5) and the base (15). 10. Metal barrel according to claim 8, characterized in that it has a closed sack-shaped lining (20) made of flexible plastic material, which is tightly connected to at least one bunghole (21), in order to completely prevent contact between the contents of the barrel and the inner walls of the barrel (19).