GB2237816A - Isolator transfer containers - Google Patents

Abstract

The transfer of materials into, and products out of, an isolator may be achieved, without compromising the containment, using a double-door transfer port (also known as a "rapid transfer port"). To make a contained transfer between the container and a lidded container, the container is "docked with" the closed port, and then from within the isolator the port door is opened. The docking of container to port may be accomplished using a bayonet system, and twisting the container around its axis to dock it into place at the port. Because the container must be physically rotated, the contents thereof are also subjected to rotation, which may spill liquids or damage delicate equipment. In order to overcome this problem, the whole of the lid (24) and bayonet-closure mechanism (35, 36) of the container (21) are housed in a short tube- or collar-like extension (30) of the container mounted on the container itself via a gas-tight slip-ring joint (30, 32). With such an arrangement, the extension is rotated to dock the container into place onto the port, but because of the slip-ring joint the container need not rotate. <IMAGE>

Description

Isolator Transfer Containers This invention relates to isolator transfer containers, and concerns in particular the means by which such a container is in use to be attached to the appropriate isolator transfer port.

In many fields of technology there is a need for work to be carried out in an environment that is safely sealed off from the rest of the world. For example, in the biological sciences it is common to work with dangerously toxic or infectious materials (such as poisons, bacteria or viruses), and it will usually be desirable to carry out this work in a fully enclosed area from which the dangerous materials cannot easily escape into, and so contaminate, the surroundings. In the pharmaceutical and electronics industries, on the other hand, it may be desirable to work on some product (such as a drug or microchip) within a scrupulously clean enclosure, so as to prevent the ambient conditions contaminating the product.

Both of these situations require a volume of space to be sealed off - isolated - from its surroundings, and to meet this need technology has produced the isolator, which comes in sizes varying from that of a large (lx1x1 m, or about 2.5x2.5x2.5 ft) box up to that of a small room).

In essence, an isolator is little more than a sealed, bubble-like envelope in the wall of which is both a hatch or port (though which articles can be passed in and out) as well as means whereby the bubble's contents can be manipulated. The envelope is naturally made of some (preferably transparent) material suitably resistant to whatever chemicals and other substances are likely to come into contact with it both inside and outside the isolator (typical such materials are flexible polyvinyl chloride - PVC - film or sheet, but some isolators can be made of rigid materials such as a glass). One very successful form of isolator available today is a cuboidal "bubble" of flexible PVC suspended from an external framework that both shapes and supports the bubble.A particularly satisfactory bubble isolator is that described and claimed in the Specification of our co-pending British Patent Application No. 88/05,817 (Publication No: 2,215,347A). That isolator is one having a tray-like base portion of a generally rigid physically and chemically resistant material upon which is sealing mounted around the edges thereof a tent-like canopy portion of a flexible 2nd transperent chemically resistant matera.

An issue central to the operation of any isolator is the transfer of materials into, and products out of, the isolated volume. This must clearly be achieved without compromising the containment, be it positive pressure sterile or negative pressure toxic, if isolator work is to continue in an unbroken sequence. There are various ways that contained transfer can be attained.

For example, there may be employed a lock chamber, or a "bagging port" for waste, but one particularly useful method utilises a double-door transfer port (also known as a "rapid transfer port"), first developed in the Nuclear Industry to minimise the hazards involved when moving radioactive materials from one glovebox to another.

The rapid transfer port system, which has now found an application wherever contained transfer is required, is in essence very simple. Basically, it involves no more than four components and two seals; two of the parts are the port itself and its door (sealable tight with one of the seals), whilst the other two are a matching box-like container and its lid (and the other seal). To make a contained transfer the lidded container is "docked with" - offered up to, and pressed into contact with - the closed port (the two external, "dirty" faces of door and lid are in face-to-face contact and sealed off by peripheral seals), and then from within the isolator the port door is opened - and the connection between the door and the container's lid is such that as the door opens so it removes, and takes into the isolator, the lid.The result is that the container is sealed to the port, and communicates therethrough with the body of the isolator to allow materials to be moved in and/or out as required.

To "undock" the transfer container, the isolator's port door is shut, and the container removed from its sealing contact with the door.

The nub of this method is the way in which the docking of container to port is accomplished, both to sealingly join the two together and to allow the container's lid to be removed simply by opening the port's door. Various mechanical devices have been used to press the container against the port, and the lid to the door, and these have involved over-centre clamps, wing-nutted hinged bolts, and so on.A particularly convenient device, however, employs a bayonet system, in which - as on a British lightbulb fitting, a series of lugs projecting laterally from around the container's mouth fit into corresponding undercut notches around the port opening; twisting the container around its axis after offering it up so the lugs fit into the notches rotates the lugs through into the undercut portion where they are trapped (usually with a camming action to effect positive retainment), and so the container is docked into place at the port. Undocking is simply the reverse; the container is "un"-rotated, the lugs now correspond to the notch openings, and the container may be removed.

It will be understood that the container lid may be secured into place by a similar but opposite-handed twist system. If, then, the port door is arranged to mesh mechanically with the lid, as the container is turned so the lid, held "still" relative to the door, twists open relative to the container - and when the door is opened, so the lid is removed. Closing the door, and reverse twisting the container, replaces and re-attaches the lid.

Though this twist bayonet system is preferred, nevertheless it does lead inevitably to a problem, which is that, because the container must be physically rotated to dock it onto the port, the contents of the container are necessarily subjected to whatever degree of rotation has to be effected (usually about 60 ), and this might spill liquids or damage delicate equipment.

Tnough this problem has existed for some time, no-or.e has suggested the answer now proposed by the invention, namely that the whole of the lid and bayonet-closure mechanism of the container should be housed in a short tube- or collar-like extension of the container mounted on the container itself via a gas-tight slip-ring Joint.

With such an arrangement, the extension is rotated to dock the container into place onto the port, but by virtue of the slip-ring joint the actual container itself need not rotate at all.

In one aspect, therefore, the invention provides a transfer container for use with an isolated, and attachable to a port thereof by a lugs-into-notches bayonet-type fitting, which container has its portlocking lugs mounted on a collar rotatably carried by the container body via a slip-ring joint, whereby the collar may be rotated, to lock (and unlock) the container to the port, while keeping the container itself stationary.

Apart from its special collar-mounted lugs arrangement, the transfer container may be of any type suited to the purpose. One particularly preferred type is that the: subject of our British Registered Design No: 1,048,376.

Similarly, the isolator may be of any convenient variety - especially one like that described and claimed in our aforementioned British Patent Specification No: 2,215,347A.

The container of the invention is securable to an isolator port by a lugs-into-notches bayonet-type fitting. This fitting may be of any suitable variety, but is preferably just like those presently used in the Art for this purpose. Thus, it has laterally projecting pins, or lugs (which are advantageously of a substantial length in the rotation direction, so as to have the requisite strength without being too thick, and are thus like elongate parts of a circular flange extending around the "opening" end of the collar), and these fit into corresponding undercut notches around the port opening.Conveniently the lug/notch combination is very slightly ramped, to provide what is in effect a cam action tightening the collar into place as ft is rotated into the "shut" position, and thereby ensuring that the isolator is connected to the port in the required sealing fashion.

The collar is rotatably carried by the container body via a slip-ring joint, allowing it to be rotated (around the common axis) while still being sealingly attached to the body. The slip-ring joint may take any suitable form; one such is a two-part device of an outer tube-like ring sealingly but slidably mounted on an inner tube-like ring and held in place against relative axial movement by co-operating flanges such that an external flat flange on the outer ring is held within the confines of an external but recurved flange on the inner ring (such a system is described hereinafter with reference to the accompanying Drawings). The sealing between the two rings may be of the O-ring type, most preferably made of a PTFE-loaded neoprene sponge material to ensure a satisfactory seal.

The inner tube-like ring of the collar variety just described may actually be the container body - or, rather, an integral part thereof forming the mouth of the body. Preferably, however, the inner ring is a separate part, and the collar combination is thus a unit that is clamped on to the open end of a more or less conventional isolator transfer container. In such a case, the rear end of the collar - that end opposed to the lug-carrying end - will bear means, usually a simple external flange, by which the collar may be attached to the isolator body (conveniently by a clamping circlip device or by a series of nuts and bolts).

In order to assist in rotating the lug-carrying part of the collar around to lock or unlock the container to the port it is preferred that there be provided handles enabling that part more easily to be grasped and rotated.

The materials employed to make the collar may be any of those suitable for the purpose, especially a synthetic resin (plastics) substance such as is used for the other parts of the isolator and container. One particular such plastics material is NYLACAST OILON, which can easily be shaped and machined as required, and has a certain inherent "slipperiness" that makes it especially suited to the task.

An embodiment of the invention is now described though by way of illustration only, with reference to the accompanying diagrammatic Drawings in which: Figure 1 shows a perspective view of an isolator; Figure 2A to C shows in part axial sectional form a sequence of attaching a transfer container to an isolator port and then opening the port door; Figure 3 shows a part axial sectional view through a collar-fitted transfer container of the invention and the associated isolator port; Figures 4A & B show a more detailed (and dimensionally-accurate) part axial sectional view through the collar and port parts of the Figure 3 apparatus; Figure 5 shows an "end-on" view on the line V-V in Figure 4; and Figure 6 shows a part sectional view on the line VI-VI of the left-hand (as viewed) handle shown in Figure 6.

The isolator (generally 10) shown ir tsif Drawings has a rigid tray-3like rinse part (il) onto which is r;nlingly mounted a transparent flexible tent-like canopy part (12). The canopy 12 is supported in place above the tray via loops (52) by a framework (50) the crossbars (51) of which also support the tray 11. The tray 11 is oblong, and has a floor (13), a perimeter wall (14), and a lip (15). The canopy 12 is cuboidal (matching the tray 11 dimensions > , and is sealingly mounted on the tray by having its open end edge folded around the tray's lip 15 and held in place by an extended U-channel trim-strip clip (not shown) that runs all the way round the base.

The glove box has the usual glove pair (generally 19) and hatch and hatchway (20).

The sequence of Figures 2A to 2C shows a shut isolator transfer container (21) being offered up and secured to the port (22) of an isolator (only a fraction, 25, of the isolator's canopy is shown), whereafter the door (23 > of the isolator is opened (from the inside), with the lid (24 > of the container attached thereto, to allow the contents (not shown) of the container to be brought into the isolator. During this procedure the outside - and thus potentially "dirty" surfaces of lid 24 and door 23 are sealed together, so as trap any dirt between the two and prevent it getting into, and so contaminating, either the container or the isolator.

Though it is not shown in this sequence, the container is docked and locked to the isolator port by engaging the lugs (not separately shown) on the former's lid surround with corresponding notches (not separately shown) on the latter's port surround. This requires the container body to be rotated through about 60 about its axis, which in the normal course of events inevitably means that the contents of the isolator will be upset.

It is this that the present invention seeks to avoid.

The inventive transfer container is shown in Figure 3 (in this Figure the upper half, as viewed, is shown with some of the sectioned surfaces hatched, for clarity). As in the Prior Art container of Figure 2, the inventive transfer container has a body 21 and a lid 24, and is adapted to lock sealingly onto a port 22 around a door 23.However, instead of flanges around and integral with the body 21 forming the "lugs" or "pins" which are to be inserted into, and locked bayonet fashion with, corresponding notches positioned around the port opening, there is a collar constructed from a short tubular outer ring (30) carried, via a sliding seal (31) on a tubular inner ring (32 > itself mounted by bolts (not shown) through its flange (33) onto a corresponding flange (34) around the container body's mouth; and it is this outer ring 30 that bears the lug (or pin) flanges (35) that will engage the port opening's notches (36). The collar is retained on the inner, slip, ring 32 by further flanges (37) clamped by ring segments < as 38) to the inner ring mounting flange 33, and is turned by two handles (39) projecting outwardly therefrom (into and out of the Figure: these are not shown in Figure 3, but can be seen in Figures 5 and 6).

The container's lid 24 is mounted not directly on the container body 21 but instead, and in a comparable flanged-lug-and-notch bayonet-fashion, at the mouth of the collar 30.

The isolator port 22 and door 23 are just like those used in the Prior Art system of Figure 2, save for the two "stabilising" pins (as 40) that project therefrom out from the port. It will be clear that these pins 40 are positioned to project towards the container (as it docks with the port), and as the docking occurs the pins are inserted into corresponding apertures, or notches (as 41), in the container collar's segment clamps 38. These pins ensure that when the handles 39 are used to turn the outer ring 30 on its inner ring 32 the container body 21 is "locked" stationary with respect to the port 22, and only the outer ring turns. Apart from that, the port and door need no further comment here.

Figures 4A and B show in much gr-eater detail, and rather more accurately, a container-and-collar combination of the invention (as shown in Figure 3), both spaced from the port (in 4A - as in Figure 3) and docked with the port (in 4B). Various extra seals are shown, including, in heavy black, the two V-seals (45, 46) that seal the lid 24 into the collar mouth and the door 23 into the port, and that meet, edge-to-edge, when the lid and door are sealed to each other (see Figure 4A). In addition, there is shown some detail of the door clamping mechanism - the central mount (46), the pressure bar (47) and the over-centre locking latch (48). This mechanism is described and claimed in the Specification of our co-pending British Patent Application No: 89/02,493.9 (Publication No: ~~~~ ~), and needs no further comment here.

Details of the arrangement of the collar's docking flanges 35, the outer-to-inner ring retaining flanges 37, the handles 39, and the stabilising pin notches 41 are shown in Figures 5 and 6. These Figures should be self-explanatory, and so need no further comment here.

Claims (10)

1. A transfer container for use with an isolator, and attachable to a DOrt thereof by a lupjs-into-notcnes bayonet-type fitting, which container has its portlocking lugs mounted on a collar rot at ably carriea by the container body via a slip-ring joint, whereby the collar may be rotated, to lock (ana uniock) the container to the port, while keeping the container itself stationary.

2. A container as claimed in Claim 1, wherein tne lugs-into-notches bayonet-type fitting has laterally projecting pins, or lugs, that fit into correrponaing undercut notches around the port opening.

3. A container as claimed in Claim 2, wherein tne bayonet-type fitting's lue are of a substantial length in these rotation direction, so as to nave the requisite strellgth without being too thick, and are tnu iLKe elongate parts of a circular flange extending around the "opening" end of the collar.

4. A container as claimed in either of Claims 2 ana , wherein the lug/notch combination is very slightly ramped, to provide wnat is in effect a cam action tightening the collar into place as it is rotated into the "shut" position, and thereby ensuring that the isolator is connected to the port in the required sealing fashion.

5. A container as claimed in any of the preceaing Claims, wherein the slip-ring Joint, by wnicn tne collar is rotatably carriea by the container body, is a twopart device of an outer tube-like ring sealingly but slideably mounted on an inner tube-like ring and nela in place against relative axial movement by co-operating flanges such tnat an e.w:teì-nai fiat flange on tne outer ring is held within the confines of an external but recurved flange on the inner ring.

6. A container as claimed in Claim 5, wherein the sealing between the two rings is of the 0-ring type.

7. A container as claimed in either of Claims 5 and 6, wherein the inner tube-like ring of the collar is a separate part, and the collar combination is thus a unit that is clamped on to the open end of the isoiator transfer container.

8. A container as claimed in Claim 7, wherein the rear end of the collar - t flat ena opposed to the lug-carrying end - Dears a simple external flange Dy wnicn the collar may be attached to the isolator boozy br a clamping circiip device or by a series of nuts and bolts.

9. A container as claimea in any of the preceding Claims, wnerein, in order to assist in rotating the lugcarrying part of the collar around to lock or unlock the container to the port, there be proviaea handles enabling that part more easily to be grasped and rotated.

10. A container as ciaimed in any of the preceding Claims and substantially as described hereinbefore.