Method and apparatus for securing a closure in an aperture of a container

An apparatus 1 for securing a closure 2 in an aperture 3 of a container 4 comprises a securing cap 5 adapted to engage the closure 2 and the container 4 to secure the closure 2, and fittings to provide for generation and release of a vacuum or partial vacuum between the securing cap 5 and the closure 2 to move the securing cap 5 into a securing position.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 371 of PCT/GB01/00332 filed Jan. 26, 2001.

Not Applicable.

THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

Not Applicable.

Not Applicable.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The invention relates to apparatus for securing a closure in an aperture of a container and to a method of securing a closure in all aperture of a container.

(2) Description of Related Art

Containers for storage and transportation of material often have apertures such as inlets and outlets with removable closures to enable the stored material to be discharged. A problem with such containers is that sometimes the closures can become dislodged or moved inadvertently for example during transport, allowing material to escape. This is a particular problem with containers for the storage and transportation of bulk quantities of materials such as pharmaceutical powders. There are now strict regulations governing the conditions for transportation of for example, hazardous materials, and ensuring that no accidental escape of material occurs is a primary consideration.

To prevent escape of material occurring it has been proposed to provide securing means such as a clamp or cap to secure the closure in place in an aperture and also to cover the aperture. Whilst such apparatus has been found to be effective, there continues to be a need for apparatus and methods which perform a number of functions economically:i. Provide a dust and weather tight cover over the entire closure and aperture;ii. Lock the closure securely into the aperture especially to meet U.N. requirements for transportation of hazardous substances;

In addition the effectiveness of the apparatus and methods must not reduce with passage of time.

It is an object of this invention to provide such apparatus and methods.

BRIEF SUMMARY OF THE INVENTION

According to the invention there is provided apparatus for securing a closure in an aperture of a container using means adapted to engage the closure and the container to secure the closure, the apparatus comprising means to provide for generation and release of a vacuum or partial vacuum between the securing means and the closure to move the securing means into a securing position. It has been found that this enables the closure to be secured and released sufficiently firmly and positively to avoid accidental material loss without disturbing the closure in the process of securing and releasing it.

It is preferred that the means to provide for generation and release of a vacuum or partial vacuum comprises airway means. It is further preferred that the airway means is adapted to cooperate with an aperture of the securing means to provide for generation and release of the vacuum or partial vacuum between the securing means and the closure. This is a convenient arrangement which allows the apparatus of the invention to be used with many different forms of securing means.

The apparatus may include second means to provide for generations and release of a vacuum or partial vacuum, the said second means being adapted to provide for generation and release of a vacuum or partial vacuum between the securing means and the apparatus. The said second means preferably comprises airway means.

The apparatus may comprise actuator means adapted to releasably engage the securing means for attachment to the container. This is a convenient arrangement which allows for accurate presentation of the securing means to the container. The actuator may be attached to a base and may be movable relative thereto.

The apparatus may include third means to provide for generation and release of a vacuum or partial vacuum, to move the actuator relative to the base. This is a convenient method of operating the actuator.

The apparatus may include seal means disposed to enable the vacuum or partial vacuum to be generated between the apparatus and the securing means although the seal means may in principle be borne by the securing means.

According to a second aspect of the invention there is provided a method of releasably securing a closure in an aperture of a container using means adapted to engage the closure and the container to secure the closure, the method comprising the use of a vacuum or partial vacuum generated between the securing means and the closure to secure or release the securing means.

The method may include the use of an actuator in moving the securing means to secure or release the closure, and may include the use of a vacuum or partial vacuum to operate the actuator.

The method may also include releasably attaching the securing means to the actuator by use of a vacuum or partial vacuum.

The method may also include the use of seal means of the securing means and/or of the container to assist in maintenance of the vacuum or partial vacuum between the securing means and the container.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings there is illustrated apparatus1for securing a closure2in an aperture3of a container4using means5adapted to engage the closure2and the container4to secure the closure2, the apparatus1comprising means6to provide for generation and release of a vacuum or partial vacuum between the securing means5and the closure2to move the securing means5into a securing position.

In this example the apparatus1is designed for fitting securing means5to an intermediate bulk container, or I.B.C.4to prevent accidental movement of the closure2. Referring toFIG. 3, the I.B.C.4is of conventional design and has an aperture3in the form of an outlet for release of material, obturated by a closure2which seats in the outlet3and seals therein via a cone valve seal ring7on a skirt8. Material is released by raising the closure2by suitable apparatus (not shown) as is known in the art.

Referring toFIGS. 1 and 2, the apparatus1is mounted on a base plate9which can also accommodate the feet of the I.B.C.4. The apparatus1comprises a body having two main parts11and12, one fixed and one movable. The fixed part11is a base and the movable part12is an actuator10. In this embodiment the parts take the form of inner and outer concentric cylinders11,12, the inner cylinder11being fixed to the base plate9and the outer cylinder12being seated there around and being movable telescopically upwardly relative to the inner cylinder11. A vacuum-tight resilient seal13is disposed on the outside surface at the top (as viewed) edge of the inner cylinder11, between it and the outer cylinder12. The seal13has two circumferential flanges13aand13bwhich facilitate movement of the outer cylinder whilst retaining a seal between the cylinders11,12. The outer cylinder12comprises a minor diameter part14and a major diameter part15, with a step in between at which is mounted on the outer surface a second vacuum-tight resilient seal16, with circumferential flanges16a,16b. The outer cylinder12has an inwardly directed flange17around the lower (as viewed) rim of the minor diameter part14and a top plate18fixed on top of the major diameter part15. A guide rod19is attached to the plate18, the guide rod19moving in a central cylinder20which is itself attached to the base plate9. The guide rod19has an aperture19ain its upper, as viewed, end and an “O”-ring seal27secured around the aperture19aand standing proud therefrom.

The apparatus1has vacuum providing means6in the form of pneumatic fittings21a,21b,21c,23and25and airways22a,22band26which are operatively attached to a device to apply suction and generate a vacuum or partial vacuum (not shown). Fitting21afeeds into the interior of the outer cylinder12. Fitting21bfeeds into flexible airway22awhich in turn feeds into fitting23and then through an aperture24in top plate18. Fitting21cfeeds into flexible airway22bwhich in turn feeds into fitting25and then into airway26which leads into the top of guide rod19in central cylinder20to aperture19a.

Referring toFIG. 2, the securing means5in this example is in the form of a cap, which consists of a circular, curved plate28which has a channel shaped rim29and at the centre of the plate28an aperture37. The rim29has an inner side wall30, a base31and an outer side wall32. The inner side wall30interfaces with the perimeter of the curved plate28creating a continuous nose33and a resilient seal ring36is fitted between nose33and base31around the inner side wall30. The rubber seal ring36has four circumferential flanges36aof varying thickness extending outwardly and downwardly as viewed. The outer side wall32has fitted upon it a circular resilient seal34which has a sealing surface35.

Referring toFIGS. 2 to 6, the sequence of operation to secure the closure2in position in the outlet3is illustrated.

InFIG. 2the apparatus1is shown with securing means5in the form of a cap engaged upon the actuator10in position ready for attaching the cap5to the I.B.C.4. The cap5is conveniently engaged on the actuator manually. The act of placement on the actuator10creates a seal between the cap5and the apparatus1at the vacuum-tight seal16.

The I.B.C.4to be capped is moved by any suitable means such as a crane into position over the apparatus1and is lowered.FIG. 3shows the I.B.C.4lowered into place on the apparatus1. Assisted by positive pressure in the chamber, the skirt8of the closure2makes contact with the seal ring36of the cap5, creating a vacuum-tight seal. Suction is applied via the pneumatic fittings21b,21c,23and25, and airways22a,22band26to generate vacuum at “A” and “A1” whilst fitting21ais vented to atmosphere. The generation of vacuum in the spaces “A” causes the cap5still engaged on the actuator10to be drawn up into the closure2(FIG. 4) extending flexible airways22aand22b, the guide rod19constraining the apparatus in a vertical, non-tilting movement. It will be appreciated that the vacuum force which needs to be applied will be sufficient to move the weight of the cap5and actuator10into the closure2against resistance from the four circumferential flanges36aof the seal36and from the sealing surface35of circular seal34and creates a very tight interference fit. It is envisaged however that a sufficiently tight seal between the skirt8and the cap5could be achieved without the need for a specific seal, for example by use of a resilient material to form the cap5. When the actuator10is fully raised and the cap5is fully in position with the lower part of skirt8adjacent the base31of rim29, the vacuum at “A” is vented via airways22aand22band fittings21band21cand suction is applied via fitting21ato generate vacuum in the void space “B” in the actuator10beneath the top plate18. This moves the outer cylinder12, top plate18and guide rod19downwardly as viewed, around inner cylinder11, leaving the cap5firmly in place on the I.B.C.4. When the actuator10is fully lowered the I.B.C.4secured with cap5together are ready to be removed from the apparatus1(FIGS. 5 and 6).

Referring toFIGS. 7 to 11, the sequence of operation to release the closure2in the aperture3is illustrated.

As shown inFIGS. 7 and 8, the I.B.C.4is first lowered into place on the apparatus1. Once in place, air pressure is applied to the void space “B” in the actuator10via fitting21a. This brings the vacuum-tight ring seal16into contact with the inner surface of the wall30. At the same time suction is applied to airways22aand22bwhich generates vacuum at “C” to raise the actuator10fully into the cap5.

Referring toFIG. 9, when the actuator10is fully raised the “0” ring27on piston19seals against the underside of the cap5. At this stage the space “D” between the cap5and closure2can be vented as the vacuum between the cap5and the actuator10keeps the “0” ring27firmly connected. Suction is then applied via fittings21aand21bto generate vacuum in the void spaces “E” and “F” which draws the actuator10down around the inner cylinder11, bringing the cap5down with it, away from the closure2.

InFIG. 10the I.B.C.4without cap5secured is illustrated ready for removal. The very light contact between seal36and closure2, with no vacuum applied, is very easy to overcome as the I.B.C.4is lifted away. Finally, inFIG. 11the vacuum in space “D” having been vented, the cap5is allowed to be removed manually from the apparatus1because the lip seal16is easy to overcome with no suction being applied. Vacuum is retained in void space “E” whilst space “F” is vented to keep the actuator10in its located position.

Referring now toFIG. 12, a further embodiment of securing means5is illustrated for use with the apparatus and method of the invention. In this illustration the container4is substantially the same as that illustrated inFIGS. 1 to 11, as is the closure2. However, in this case the securing means5comprises two parts, an inner part100and an outer part101which cooperate to secure the closure2in the outlet3. The outer part101comprises a ring102which has an upper, as viewed, channel part102awith two or more resilient leaf springs103attached around its inner circumference. Each leaf spring103carries a resilient, in this case plastic, nose104at its end remote from the ring102. A seal105is disposed about the inner circumference of the ring102. The inner part100takes the form of an up-turned cup, the diameter of the cup being such as to allow it to fit through the ring102the wall106of the cup sealing with a seal110of the outer part101as the base107of the cup meets the closure2. An aperture108is provided in the base107.

In use in securing the closure2in the outlet3, the outer part101is offered up to the container4so that the skirt8and outlet3are received in the channel part102a, sealing with a seal105of the channel part102a. The inner part100is engaged upon the actuator10which seals against the inside of wall106and is then moved by means of suction applied through aperture108between itself and the closure2, upwardly into the closure2, displacing outwardly the leaf springs103so that the noses104are forced against the closure2and skirt8. Once in place, the vacuum formed between the inner part100and the closure2can be vented. Thus, operation of this form of securing means5to secure and release the closure2using the apparatus1is substantially as described in the previous embodiment.

FIG. 13illustrates a further alternative embodiment of apparatus200for securing a closure in an aperture of a container. The apparatus200is of the same general form as illustrated previously herein and is shown in a position corresponding to the position of the apparatus1shown inFIG. 2with securing means in the form of a cap500in place thereon. The apparatus200comprises means600to provide for generation and release of a vacuum or partial vacuum between the securing means and a closure of a container to move the securing means500into a securing position. The apparatus is mounted on a base plate900and comprises a body having two main parts,210and220, one fixed and one movable. In this embodiment the parts take the form of an inner cylinder210, with a circular actuator220thereon, the actuator comprising an annular flange221and being dimensioned to fit over the cylinder210to receive it therein. As in other embodiments, cylinder210is fixed to the base plate900. Actuator220is movable telescopically upwardly relative to cylinder210. A vacuum-tight resilient seal230is disposed between the cylinder210and the actuator220. The actuator220includes on its upper (in use) surface at the perimeter thereof an annular seal216which is vacuum-tight, with circumferential flanges260a,260band260c. In this position the seal216makes it particularly easy to remorse the cap500from the actuator220by hand. In this embodiment it will be noted that there is two central guide rod. Instead, three off guide bars290(two are shown) are provided primarily to limit the upstroke. Each has a coil spring290awhich helps to lower the actuator220. A pneumatic switch270is provided to confirm that the actuator is fully lowered before bin removal. The switch could be electrical, electronic or other, and could be fitted to the other embodiments described above. It will be noted that in this embodiment the cap500does not have a seal corresponding to seal34as previously described, but instead the outer side wall320is enlarged and itself provided with a sealing surface350.

As will be appreciated, this embodiment is operated in the same way as previously described and as such this will not be repeated.

As will be appreciated, the invention is applicable to container inlets and lids as well as outlets and closures. In this example rubber seals are utilised, however, inflatable or other types of seals might be used.