WO1999036327A1

WO1999036327A1 - Safety lid fastener for receptacles containing hazardous products

Info

Publication number: WO1999036327A1
Application number: PCT/EP1999/000151
Authority: WO
Inventors: Sergio Loschi
Original assignee: Femm S.R.L.
Priority date: 1998-01-14
Filing date: 1999-01-05
Publication date: 1999-07-22
Also published as: AU2517599A; IT1304261B1; ITRE980006A1

Abstract

A safety fastener for clamping the respective lids (2) onto containers (1) provided with an external bead (10) surrounding their mouth, and comprising an endless ring-shaped metal body provided with a predetermined fracture zone (34, 35), is provided with two engagement seats (6) which straddle said predetermined fracture zone and with which there is removably associated a locking unit (4) for tightening said annular body (3) once said predetermined fracture zone has been lacerated.

Description

SAFETY LID FASTE.NER FOR RECEPTACLES CONTAINING HAZARDOUS PRODUCTS

Technical field

This invention relates in a totally general manner to the closure of metal containers and receptacles, such as buckets, cans, drums and the like, and more particularly concerns the closure of metal receptacles for containing dangerous, noxious and/or contaminant substances, such as acids, paints, diluents and the like. More specifically, the invention relates to a fastener device ensuring correct and reliable clamping of the respective lids onto such metal receptacles and containers, the mouth of which comprises a projecting circumferential bead obtained by outwardly turning the respective upper edge,

Background art

As is well known, to obviate damage deriving from untimely leakage and spillage of said dangerous or noxious containers during their handling and transport, a large number of countries have enacted laws according to which the lid must ensure closure of the respective container even when subjected to impaGt and/or deformation. Moreover, in many countries rather severe regulations are in force whiGh require a receptacle containing such products to maintain its seal even when the receptacle falls when full from a height exceeding one metre, and with any inclination of its longitudinal axis to the vertical. Two systems are currently known for securing the lid and container of such metal receptacles together, one using an open ring with which a toggle clamping device is permanently associated, and the other using a closed ring provided with a predetermined fracture zone. With said first known system, the respective open ring has a channel -shaped cross-section, the lateral walls of which fit over the peripheral edge of the lid and under the rim of the upper bead of the receptacle, so as to firmly clamp said lid and said bead together when the toggle clamping device is m the locking configuration. The aforedescri ed known system has exhibited the following problems.

Firstly, said open-ring fastening system has proved unsatisfactory because various operations are required to close and open the toggle clamping device before the full receptacle can be released for commercial distribution.

In this respect, τo facilitate easy and ordered transportation of complete empty receptacles to the production and filling site for such dangerous and noxious products, the respective containers are piled by inserting o e into another, the respective lids being stacked separately together with their rings, which have to be fitted to the lids, this havmg to be done manually with resultant considerable time requirement and cost, m that the numerous attempts to automate this operation have not yet given a positive result. Said toggle clamping device also has to be manually closed and opened when the lid is to be secured to the container after fill ing.

In addition, said toggle clamping device has proved constructional ly complex, and hence also relatively costly. Specifically, it comprises: a first fixing element to be welded to one end of the open ring, a second fixing element to be welded to the opposite end of the open ring, - a connecting rod hinged at one end to one of said fixing elements, and an operating lever which at one end is hinged to the other of said fixing elements, at an intermediate point pivotally carries the other end of said connecting rod, and at the opposite end comprises a handgrip for operating the toggle clamping device.

With the aforesaid second known system, the respective closed rinα has a substantially cylindrical thin metal body with an inwardly turned-over circumferential edge and an opposite flat circumferential edge, to be mounted on the top of a container such that said turned-over edge rests against the peripheral edge of the lid, with said flat edge extending beyond the external bead provided at the top of said container, to be bent under and against said bead.

In addition, as already stated, the closed ring is provided with a predetermined fracture zone, for further constructional details of which reference should be made to Italian Industrial Invention. Patent No. 1237573,

Said closed ring satisfies the seal tests defined by the current regulations on this subject, and in particular satisfies said free fall test, however it has the serious drawback of not being able to be reused to again close the respective container once this has been opened.

This is obviously of no importance if all the product contained therein is used, however if the product is only partially used, as often happens, there is the constant danger of untimely leakage and spillage, with all its resultant effects.

Consequently in this specific sector there is a considerable requirement for fastening means which on the one hand are able to satisfy current regulations, and on the other hand ensure sealed closure of such metal receptacles even after they have been opened .

The main object of this invention is to satisfy said requirement within the context of a simple and rational construction.

Disclosure of the invention Said object is attained according to the invention by a safety fastener as defined in the claims.

The safety fastener of the invention is of the type comprising a metal body of closed-ring shape provided with a predetermined fracture zone, and with two engagement seats which straddle said predetermined fracture zone and with which there is removably associated a locking unit for tightening the metal annular body once said predetermined fracture zone has been lacerated. All the objects of the invention are satisfied by the aforesaid means, in that sealed closure of the respective receptacle is ensured both while the ring is still unbroken and when it has been broken, with consequent removal of the danger of sp lling of any unused product still present in the opened receptacle. As will be apparent hereinafter, other advantages deriving from the provision of the removable locking unit are the fact that said unit in no way hinders the gripping of the respective container by the ring, and that the umt creates no transport problems for empty containers.

The constructional characteristics aoό merits of the invention w ll be more apparent from the figures of the accompanying drawings, which show a particular embodiment of the invention by way of non-limiting example.

Figure 1 is an exploded perspective view showing the invention positioned above a container with relative lid, the locking unit being separated from the respective closed ring. Figure 2 is a section on the line II—II of Figure 1 to an enlarged scale, the locking unit shown associated with the integral (or broken) ring gripping the container.

Figure 3 is a section on the line III—II i of Figure 2 to a smaller scale, the ring being shown broken but still gripping the container by virtue of its tightening by the locking unit. Said figures, and in particular Figure 1, show a metal container 1 of substantially cylindrical shape, an overlying metal lid of discoidal shape, and a circular metal ring 3 provided with the locking unit indicated by 4. The mouth of the container 1 comprises a usual projecting bead 10, formed by outwardly turning-over its upper circumferential edge, against which the lid 2 is intended to rest to prevent exit of the product 5 (see Figure 2), for example in the form of diluent, paint or acid. The ring, shaped in the manner of a collar, is formed from a metal strip of suitable width and length, and has its opposing ends 30 superposed and connected together by tne punched spots indicated by 31.

The ring 3 has a usual right-angled cross-section, the upper flange of said right-angled shape consisting of an inwardly turned edge 32 and the lower flange consisting of a substantially cylindrical descending skirt 33.

The ring 3 is provided with two usual close-together predetermined fracture lines 34, with a likewise usual aperture 35 for receiving a tool, such as the head of a screwdriver, with which the ring 3 is broken when the product 5 is to be used. When the container 1 has been filled, said lid 2 and said ring 3 are positioned on it, with the lower edge of the skirt 33 of this latter extending beyond the lower generators of the bead 10, as shown by dashed and dotted lines in Figure 2. Said skirt 33 is then turned in usual manner, below and against said bead, so that the ring 3 grips the container to securely retain the lid 3 thereon (see turned skirt position shown by full 1 ines in Figure 2) .

When the product 5 is to be used, the ring is fractured along the lines 34, so that the ring now comprises the gap indicated by 340 in Figure 3.

According to the invention the container can be resealed by the means described hereinafter after the ring 3 has been broken, for example if only part of the product 5 has been used. As shown, external to the removable zone defined by the predetermined fracture lines 34 there are provided two apertures 6 acting as coupling seats for the locking unit 4. Said apertures 6 are specifically in the form of circular holes to prevent any notGhes forming whiGh could trigger breakages when the receptacle is subjected to stress or impact. Said apertures are provided for engagement by the curved ends of two hooks 40 and 41 pivoted to a locking and release lever 42 shown in Figures 1 and 3,

The hook 41 is straight and is pivoted at 43 to one end of said lever 42, whereas the hook 40 is shaped as a right angle and is pivoted to an intermediate point 44 of said lever 42, the remainder of which forms a handgrip for operating the unit 4, When the hooks 40, 41 have been hooked into the apertures 6 as shown by the arrows in Figure 1, the lever 42 is rotated towards the container 1 to put the previously fractured ring 3 under tension and securely maintain it in that state by virtue of the fact that the pivotal point 44 becomes positioned subcentre relative to the pivotal point 43 (see Figure 3). The merits and advantages of the invention are apparent from the aforegoing and from an examination of the accompanying figures. The invention is not limited to that illustrated and described, but can comprise all technical equivalents of the invention and their combinations, if implemented within the context of the fol lowing claims.

Claims

Cl aims

1. A safety fastener for clamping the respective lids (2) onto containers (1) provided with an external bead (10) surrounding their mouth, and comprising an endless rmg-shaped metal body provided with a predetermined fracture zone (34, 35), characterised by comprising two engagement seats (6) which straddle said predetermined fracture zone and with which there is removably associated a locking unit (4) for tightening said a nula body (3) once said predetermined fracture zone has been lacerated.

2. A fastener as claimed in claim i, characterised in that said two engagement seats consist of two through apertures.

3. A fastener as claimed in claim 2, characterised m that said through apertures consist of circular holes

4. A fastener as claimed in claim 1, characterised in that said locking unit comprises two hooks (40) and (41) which at one end are to be hooked into said engagement seats, and at their other end are pivoted to two separate terminal points of an operating lever (42).