GB2197303A

GB2197303A - Transport and storage container with screw closure

Info

Publication number: GB2197303A
Application number: GB08724909A
Authority: GB
Inventors: Winfried Trinkaus; Helmuth Krauss
Original assignee: Merck Patent GmbH
Current assignee: Merck Patent GmbH
Priority date: 1986-10-30
Filing date: 1987-10-23
Publication date: 1988-05-18
Anticipated expiration: 2007-10-23
Also published as: GB8724909D0; DE3636887A1; GB2197303B; FR2605989A1; DE3636887C2; FR2605989B1

Abstract

A transport and storage container made of synthetic resin for very pure liquid chemicals having a screw closure comprises a threaded connection piece provided in the upper container wall and a screw cap, wherein, within the threaded connection piece (3), there is sealingly and removably arranged an immersion tube insert (5) which has an immersion tube (8), said immersion tube (8) projecting into the inner chamber of the container, and at least one gas inlet connection piece (9, 10), each of which is provided with a screw closure (11, 12). <IMAGE>

Description

SPECIFICATION Transport and storage container with screw closure The present invention is concerned with a transport and storage container made of synthetic resin for very pure liquid chemicals and having a screw closure which comprises of a threaded connection piece provided in an upper container wall and a screw cap.

For the production of electronic constructional elements, in many cases liquid chemicals are needed, the purity of which must be as high as possible. In the case of transport, storage and handling of these chemicals, all contaminations must be avoided. Since, in many cases, these chemicals are toxic or harmful in some other way, an inadvertant flowing off, for example due to damaging of the transport or storage container, must be excluded with high certainty. Therefore, there are strict regulations for the authorisation of such transport and storage containers. In particular, because of the necessary testing, the procedure for a new authorisation of a transport and storage container takes a comparatively long time.

Transport and storage containers of the intially mentioned kind are permitted for toxic chemicals and/or chemicals harmful in some other way and are in use. The threaded connection piece, closable with a screw cap, in the upper container wall forms a sufficiently large cleaning opening. Emptying takes place through a bottom' outlet, an air inlet thereby being opened on the upper side of the container. Alternatively, the liquid can also be pumped off from the container by means of a pump pipe.

These possibilities of removal permit the entry of contaminations, at least in small amounts, and are, therefore, not suitable for handling very pure chemicals. The application of an immersion tube remaining on the container and of a gas inlet connection piece, through which an inert gas can be introduced in the case of liquid removal, would also require external constructional changes of the transport and storage container so that a renewed authorisation would be necessary, with the result that a bringing into use of the container could be delayed by more than a year.

Therefore, it is an object of the present invention so to modify a transport and storage container of the initially mentioned kind that, without impairment of the cleaning possibilities and without external constructional change and thus without the necessity of a renewed authorisation procedure, there is provided the possibility of removing liquid under very pure operational conditions.

Thus, according to the present invention, there is provided a transport and storage container made of synthetic resin for very pure liquid chemicals having a screw closure which comprises a threaded connection piece provided in an upper container wall and a screw cap, wherein, within the threaded connection piece, there is sealingly and removably arranged an immersion tube insert which has an immersion tube, said immersion tube projecting into the inner chamber of the container, and at least one gas inlet connection piece, each of which is provided with a screw closure.

The whole immersion tube insert, including the screw closures, is arranged within the space enclosed by the threaded connection piece and the screw cap placed thereon and thus in not visible from the outside. On the transport and storage container itself, no constructional measures influencing the strength or sealing are necessary so that the operational authorisation of the transport and storage container remains valid. Transport and storage containers already available and/or permitted in the scope of an existing operational authorisation can be adapted, with low expense, for the reception of very pure liquid chemicals, the removal of which is made possible by the immersion tube with simultaneous introduction of an inert gas.

Since the immersion tube insert is used sealingly, the sealing of the container is maintained, even after removal of the screw cap arranged thereover. The removable arrangement of the immersion tube insert makes possible the unhindered access to the cleaning opening after the immersion tube insert has been taken out.

Since the immersion tube insert is arranged, during the transport and the storage, under the tightly closing screw cap, it is protected against contaminations which otherwise could get into the liquid in the case of the connection of the immersion tube on to the associated removal devices.

According to a preferred embodiment of the present invention, the threaded connection piece has an inwardly projecting rotating lower section, at a distance above the section are arranged at least two holding projections and the immersion tube insert, with radially outwardly projecting fixing projections, which can each be inserted from above into an intermediate space between two adjacent holding projections and can be rotated in the manner of a bayonet joint under the fixing projections.

The immersion tube insert in the incorporated state is thereby also upwardly secured against a movement. Therefore, there is no danger that the immersion tube insert, after removal of the screw cap, is pressed upwardly out of its sealingly incorporated position if a slight overpressure exists in the container. Such a slight overpressure is also permissible in the case of synthetic resin containers of the initially mentioned kind which are not made as pressure containers and, in many cases, is unavoidable.

In comparison with an also possible screw fixing of the immersion tube insert in the threaded connection piece of the transport and storage container, the bayonet joint gives the advantage that the projections to be provided on the inner surface of the threaded connection piece and on the outer surface of the immersion tube insert are comparatively simple.

Preferably, a locking ring, useable in the threaded connection piece, engages in each case into a locking projection from above through the intermediate spaces between adjacent holding projections of the threaded connection piece into the intermediate spaces between adjacent fixing projections of the immersion tube insert. This locking ring thus prevents the immersion tube insert being inadvertantly turned. The immersion tube insert is thus positively locked in its operational position without the locking ring being stressed by upwardly directed forces which could lift it out of its locking position.

It is also advantageous to secure the locking ring in that the screw cap has a lower stop surface securing the locking ring in its incorporated position.

The sealing between the immersion tube insert and the threaded connection piece of the container is achieved in a constructionally especially simple way by arranging the locking ring between the inner surface of the threaded connection piece and the outer surface of the immersion tube insert and sealing it off against these two surfaces by sealing rings.

The locking ring sealingly bridges the distance, due to the fixing projections and the holding projections, between the inner surface of the threaded connection piece and the outer surface of the immersion tube insert.

Further advantageous embodiments of the present invention are disclosed in the subsidiary claims.

The present invention will now be explained in more detail with reference to a specific example which is illustrated in the accompanying drawings, wherein: Figure 1 is a vertical section of a screw closure in a transport and storage container for very pure liquid chemicals with an immersion tube insert; Figure 2 is a plan view of the immersion tube insert according to Figure 1, the illustration in Figure 1 corresponding to the section line 11-Il in Figure 2, and; Figure 3 is an exploded view of the threaded connection piece of the screw closure illustrated in Figure 1 with the immersion tube insert and the locking ring.

In an upper container wall 1 of an otherwise not illustrated transport and storage container made of synthetic resin for very pure liquid chemicals, there is provided a screw closure 2 which comprises a threaded connection piece 3 placed on the container wail 1 and, for example, welded with this and a screw cap 4 which closes the threaded connection piece 3.

The threaded connection piece 3, which is made with comparatively large diameter, surrounds a cleaning opening for the transport and storage container.

In the threaded connection piece 3 is placed an immersion tube insert 5 which has a bottom 6, the edge of which is provided with an upwardly extended border 7. In the bottom 6 are provided an immersion tube 8 and two gas inlet connection pieces 9 and 10. These parts are preferably produced in one piece from synthetic resin and the lower part of the immersion tube 8 can be welded on. The immersion tube 8 and the gas inlet connection pieces 9 and 10 are, on their openings lying above the bottom 6, in each case closed during transport and storage by screw closures 11 and 12 which are not shown in Figure 2.

The edge of the container wall 1 surrounding the cleaning opening forms, on the lower end of the threaded connection piece 3, an inwardly projecting surrounding lower section 13. At a distance above this section 13, there project inwardly from the inner surface 14 of the threaded connection piece 3, on two oppositely-lying sides, two holding projections which, in the case of the illustrated embodiment, each assume a segmental angle of somewhat less than 90".

From the outer surface 16 of the immersion tube insert 5, there project radially outwardly, on two oppositely-lying sides, two fixing projections 17 which, as can be seen in Figure 2, each also assume a segmental angle of somewhat less than 90". These fixing projections 17, made as ribs running in the circumferential direction, are, in the case of insertion of the immersion tube insert 5 from above, each introduced from above into the intermediate spaces between the two holding projections 15 and subsequently turned through 90" so that, in the manner of a bayonet joint, they engage under the holding projections 15 which are also made in the manner of circumferential ribs.

A locking ring 18 is placed in the gap between the inner surface 14 of the threaded connection piece 3 and the outer surface 16 of the immersion tube insert 5. Two locking projections 19 provided on the lower side of the locking ring 18, extending substantially over a segmental angle of 90 , engage from above through the intermediate space between adjacent holding projections 1 5 into the intermediate spaces between adjacent fixing projections 1 7 and thus lock the immersion tube insert 5 against rotation. This position of the parts, illustrated in an exploded view in Figure 3, is indicated in the lower part of Figure 3 by broken lines.

In the outer surface 16 of the immersion tube insert 5 is arranged a sealing ring 20 which seals off the immersion tube insert 5 against the inner surface of the locking ring 18. In the same way, in the outer surface of the locking ring is arranged a sealing ring 21 which seals off against the inner surface 14 of the threaded connection piece 3. In this way, in the assembled state of the immersion tube insert 5, there is achieved a complete sealing against the container wall 1. Even after removal of the screw cap 4, the sealing remains effective. The screw cap 4 has a lower stop surface 22 which, in the screwed-on state, is present above the locking ring 19 and secures this in its assembled position.

After the removal of the screw cap 4, the screw connections 11 and 12 are accessible which, under clean conditions, are removed in order to attach a filling or removal device.

When the container is to be cleaned, after the taking out of the immersion tube insert 5, the cleaning opening is completely accessible.

Claims

1. Transport and storage container made of synthetic resin for very pure liquid chemicals having a screw closure which comprises a threaded connection piece provided in an upper container wall and a screw cap, wherein, within the threaded connection piece, there is sealingly and removably arranged an immersion tube insert which has an immersion tube, said immersion tube projecting into the inner chamber of the container, and at least one gas inlet connection piece, each of which is provided with a screw closure.

2. Transport and storage container according to claim 1, wherein the threaded connection piece has an inwardly projecting, rotating lower section, at a distance above the section are arranged at least two holding projections and the immersion tube insert, with radially outwardly projecting fixing projections, is adapted to be inserted from above into an intermediate space between two adjacent holding projections and is rotatable in the manner of a bayonet joint under the holding projections.

3. Transport and storage container according to claim 2, wherein a locking ring insertable into the threaded connection piece from above engages through the intermediate space between adjacent holding projections of the threaded connection piece into the intermediate space between adjacent fixing projections of the immersion tube insert.

4. Transport and storage container according to claim 3, wherein the locking ring is arranged between the inner surface of the threaded connection piece and the outer surface of the immersion tube insert and is sealed off against these two surfaces by sealing rings.

5. Transport and storage container according to claim 4, wherein the screw cap has a stop surface securing the locking ring in its assembled position.

6. Transport and storage container according to any of the preceding claims, wherein the immersion tube insert has a bottom in which are positioned the immersion tube and the gas inlet connection pieces and the edge of the bottom is provided with an upwardly extending edge.

7. Transport and storage container according to claim 1, substantially as hereinbefore described and exemplified and with reference to the accompanying drawings.