Valve

A valve apparatus (100) for use in sterile fluid transfer or isolator systems has open entry (10) and exit (11) sides and a passageway (9) for fluid between the entry (10) and the exit (11) sides. The entry side (10) is connectable to an opening (4c) of a vessel or pipe (4) and the exit side (11) is connectable to downstream processing by means such as tubing, a vessel or a pipe. The entry side (10) includes a rupturable seal (2a) blocking the open entry side (10). Valve (100) also includes an actuator (5) attached to a piston (1) which moves within the valve (100), the piston being connected to the seal so that on movement of the piston, the seal is torn free from the entry side thereby allowing fluid gain entry to the valve (100) and to pass along the passageway (9) between the open entry (10) and exit (11) sides to downstream processing.

FIELD OF THE INVENTION

The present invention relates to a valve apparatus and in particular to a valve apparatus useful in systems for the sterile transfer of fluids.

BACKGROUND OF THE INVENTION

Validation and accountability are vital in most scientific industries and especially so in the pharmaceutical and biotechnological industries. A major challenge to these industries is the need to demonstrate accurately and reproducibly that sterility is achieved and maintained throughout production lines within a plant. This must be done in a manner which meets the stringent requirements of regulatory bodies such as the United States FDA. Acceptable standards can be difficult to be met when a substance is transferred from one sterile location to another sterile location by non direct means.

One current practice includes provides a holding vessel into which substance can be transferred by means of a connecting valve. The holding vessel is transferred to the second sterile location and the substance is then transferred from the holding vessel into the second sterile location via one or more connecting valves. The connecting valves and holding vessel can be sterilised using conventional techniques such as gas, radiation or steam sterilisation. However during connection of the connecting valve to the first sterile location, the external connecting surface of the connecting valve is exposed to the atmosphere and sterility of the valve is compromised.

Alternative methods of substance transfer suffer from similar problems.

For example, in the use of an autoclavable port, where a non-sterile male port is attached to an empty non-sterile bulk vessel prior to sterilization, the entire assembled apparatus is then sterilised by autoclaving. However, a major disadvantage of this technique is that the vessel must be empty before sterilisation.

Alternatively, an irradiated port can be used, where a non-sterile male port is attached to an empty non-sterile disposable bag prior to sterilisation of the whole by irradiation. Again a major disadvantage associated with this system is that the bag must be empty before sterilisation.

A further method of substance transfer involves connecting a transfer port to a vessel under aseptic conditions. With this method it is irrelevant whether or not the vessel is empty or filled. However despite the necessity to undertake these actions in a designated ‘Grade A’ zone, there is an increased risk of contamination due to the making and breaking of various connections. The mere fact that a ‘Grade A’ zone is required to complete these actions requires a significant financial investment by a company wishing to employ this technique.

Another technique incorporates the use of a tube fuser. A sterile bulk vessel is attached to tubing emanating from a sterile port through a tube fuser. This technique is undesirable for numerous reasons including the restricted choice of tubing. This in turn limits the types of substance that can be transferred through the tubing. It is also undesirable to use wetted tubing. Furthermore there is also a potential risk of cross-contamination and re-contamination.

Despite the numerous attempts to find a sterile method of substance transfer none have been wholly successful. In all of the above techniques the sterility of the port or valve used to transfer the substance from one vessel to another is compromised during the connection process or is susceptible to contamination. This is undesirable and leads to problems when validating a product.

Piston-operated valves for the above applications are known. These act by moving a piston up and down or sliding over and back within an apertured housing so as to cover or uncover the fluid communication apertures of the housing. O-ring seals are provided for sealing between the open and closed valve positions. Such valves therefore have slots for receiving the O-rings and the difficulties of assuring that these slots and the spaces about them are not subject to contamination render them questionable for use in sterile transfer systems.

OBJECTS OF THE INVENTION

It is an object of the present invention to seek to alleviate the aforementioned problems.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides a valve comprising a body having first and second open ends and a passageway for fluid between the ends, the first end including a coupling means for sealingly connecting the body about an opening of an external device and a seal blocking the open area of the first end which in use is placeable in register with the opening of the external device, the valve further including a seal displacement means movable within the body so as to interrupt the seal permitting fluid to pass along the passageway between the ends, the coupling means and seal presenting an external sterilisable mating surface for sealingly mating with a mating surface about the opening in the external device. Ideally, the displacement means comprises a means for rupturing the seal so as to allow fluid communication between the interiors of the body and the external device.

In a preferred arrangement the seal is formed integrally with the coupling means at the sterilisable external surface. Ideally, a junction is provided between the coupling means and the seal and comprises at least one weakened fracture line so that when the rupturing means moves within the body it breaks the seal along at least a portion of the at least one fracture line. Preferably, the junction or fracture line comprises an area of reduced thickness of the mating surface. Ideally, the fracture line is endless and encloses the seal, which may be punched or stamped out of the coupling means or torn free therefrom. In a particularly preferred arrangement the fracture line is in the shape of a circle and the seal is disc shaped, and when the rupturing means is moved, it causes the disc shaped seal to be displaced from its position blocking the opening of the first end.

The rupturing means may be arranged to break the seal either by puncturing through it or stamping through it outwardly, or by gripping it and withdrawing the seal or a portion of it away from the mating surface. For this purpose, mutually engageable gripping means are ideally provided on the seal and rupturing means. In a preferred arrangement, the rupturing means is moveable within the body of the valve in a direction from the first end toward the second end so that on movement of the rupturing means, the gripped seal is broken free from the coupling means and withdrawn into the interior of the body.

Ideally, the gripping means include at least one finger element projecting into the valve interior from the inner surface of the seal and a receiver element provided on the rupturing means for securely receiving and retaining the finger element. One suitable arrangement provides a plurality of fingers which are shaped to snap-fit onto a retaining portion of the rupturing means.

The rupturing means may conveniently comprise a piston. Most conveniently the piston is hollow and has an open end comprising the second open end of the valve body.

Ideally, the coupling means includes an upstanding cylindrical portion within which the piston moves. Conveniently, the piston is disposed within the cylindrical portion and one or more sealing means are positioned between the external surface of the piston and the internal surface of the cylindrical portion. This provides an effective seal between the piston and the cylindrical portion, preventing fluid from passing into or out of the area intermediate the piston and the cylindrical portion. Ideally, the piston sealing means comprises O-ring or mating sealing edges. Any other sealing mechanism know to a person skilled in the art can also be used.

One or more apertures are provided in the wall of the piston adjacent the seal so that fluid may pass between the interior of the piston and the first end via the or each aperture.

In an advantageous arrangement, the base of the piston, close to the seal, includes a depending ring portion and the fingers projecting upwardly from the seal have projections at their tips which snap onto the ring to retain the seal and piston securely connected together. These fingers are preferably resiliently biased into the engaged position. As a further security measure, a plug may be provided to be receivable between the fingers so as to lock them into their position engaged with the piston. The ring portion ideally has a reduced external diameter compared to the external diameter of the base of the piston so that the passage of fluid to the interior of the piston after removal of the seal is facilitated.

Advantageously, an actuation means is provided for moving the piston between a ready state in which the seal is intact and the valve is closed and a deployed state in which the seal is broken and moved with the piston away from the mating surface into the cylindrical portion of the coupling means so that the valve is open.

Advantageously, the second end of the body is attachable to a pipe, pipeloop, multiple pipe connections or vessel to or from which fluid is transferred.

Advantageously, the seal may be provided either as a surface continuous with the coupling means at the entry side (first end) of the valve body or as an attachment which is attachable to the entry side. If the seal is being provided as an attachment, it ideally has a shape that fits the entry side of the housing thereby providing a secure connection that prevents fluid from flowing into the valve. In one convenient arrangement the attachment is in the shape of a disc. It may be formed and shaped to provide a secondary function of acting as a sealing washer between the valve and vessel to which it is coupled when the valve and vessel are secured together. Advantageously the seal is formed from an appropriate plastics material such as polypropylene and may be coated with a non-stick material such as TEFLON™. The material of the seal is not limited to plastics materials and any suitable material known to a person skilled in the art can be used. Ideally the material selected will have received approval for use in the pharmaceutical or biotechnological industries from an appropriate regulatory authority. Plastics, rubber, metal, foil and other seals, whether flexible and/or stretchable or not, are all contemplated to be useful within the scope of the invention.

Advantageously, the actuation means include a handle operable by a user and a collar portion connected to the cylindrical portion of the coupling means and to the piston for effecting relative movement between the cylindrical portion and the piston. Ideally, the piston and gripped seal are withdrawn into the cylindrical portion of the coupling means as the actuator moves the piston from the ready (valve closed) state to the deployed (valve open) state. It is preferable for the actuation means to include a safety lock means for preventing undesired such relative movement. Ideally the safety lock means comprises a tongue releasably engageable with the piston for preventing movement from the ready state to the deployed state. The safety lock means prevents movement of the actuation means, however once released, the actuation means are free to activate the piston and rupture the seal. The actuation means and safety locking device are not limited to those described above and alternative suitable actuation means and/or safety lock means may be selected.

When the handle is turned, the piston is driven by the actuator collar to move in a direction away from the seal location at the first end (or entry side) of the housing causing the seal to rupture and fluid to gain entry to the valve interior. As the piston moves in this direction, it pulls the attached seal with it so that the seal breaks along the fracture line and the seal is carried into the cylindrical portion. Fluid can then flow, via the apertures in the piston wall between the first and second (or entry and exit) ends of the valve.

Stop means are provided for preventing the actuator from moving in a reverse direction which would return the value from the deployed (open) state to the ready (closed) state. This has the advantage that the valve may not inadvertently or mischievously be returned to a closed state having previously been open and accordingly, a user knows that when the valve is closed, it cannot have previously been compromised by an unknown opening.

Usefully, visible or tactile indication means are provided on the valve for indicating to a user the position of the valve between the ready and deployed states. Furthermore, means are provided for moving the valve into an intermediate position between the ready and deployed states. In the intermediate position, the valve remains closed with the seal intact, but the lock which retains the valve closed has been released. Means are provided for retaining the valve in this intermediate condition and the indication means are useful for alerting the user to the fact that this intermediate condition is assumed.

Advantageously, the valve can be provided as a single-use disposable valve or as a multi-use valve.

Conveniently, a single-use disposable valve is fabricated from an appropriate plastics material, optionally coated with a non-stick coating such as TEFLON™.

Advantageously a muiti-use valve has component, parts which are fabricated from an appropriate heavy duty material such as stainless steel or the like. Ideally, in this case the seal is provided as a replaceable component and is formed from an appropriate plastics material optionally coated with silicon or other non-stick material such as TEFLON™ or as a metal, foil, rubber or other membrane. The seal can be used one or more times depending on its nature and provided that the integrity of the seal per se is not compromised on opening the valve. After each use the seal is removed and cleaned or replaced, the valve is cleaned and the new or cleaned unbroken seal is inserted into the appropriate position. If the same seal is used several times, it is preferable that it be discarded after about five uses and replaced with a new seal, in order to maintain the integrity of the system. Obviously, if the seal is of the type which is punctured when the piston drives through it, then it will have to be replaced for each use.

The materials of the valve are selected so that the valve can be sterilised using suitable techniques known in the art, such as gamma ray, ethylene oxide gas or steam sterilisation, prior to use.

The valve is supplied sterile and packed. This package may include other components to be used in a sterile transfer process. In order to use it, the package is opened and the valve is removed, causing the mating surface at the first (entry side) end to become contaminated. This external surface is connected by the coupling means to an external line or vessel so that the valve first end opening and the opening to the interior of the line or vessel are in register, with the seal closing the space between them. The contaminated external surfaces of the seal is then steam sterilised together with the interior of the line or vessel. Thereafter, the valve may be opened.

Once the contaminated external face of the seal has been resterilised, the lock means of the actuator is released and the actuation means is operated to cause the piston to break the seal enabling fluid flow between the vessel and the valve. Obviously, the other, second, open end of the valve will also be connected to a vessel or pipe or the like before opening the valve.

It will be appreciated that the safety lock prevents undesired movement of the actuation means. Accordingly, this lock acts as a warning indicator to a user. If the lock device is engaged while the valve is being attached to the opening of the vessel and/or pipe and remains locked while the sealed entry side of the valve is being resterilised, the user knows definitively that the seal is intact and sterility of the valve is uncompromised. However, if the safety lock is released during the same period, the user knows immediately that the seal may have ruptured and sterility of the valve may be compromised. This enables a user to visually check whether a safe sterile transfer of fluid from one sterile location to another can be attempted.

Suitable materials for fabricating the individual components of the valve include plastics material (for example polypropylene and other suitable sterilisable plastics), metals, ceramics and so on. For a multi-use valve, durable, resterilisable materials such as metals (for example stainless steel) will be particularly suitable.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring initially toFIGS. 1ato1kandFIG. 9, there is shown a first embodiment of a single-use valve100according to the invention in its closed state. Valve100comprises a housing2having a bore for receiving a hollow piston1. Valve100has an entry side generally designated10and an exit side generally designated11. At the entry side, housing2is connectable to a vessel4so that the fluid paths of the opening4cin vessel4and fluid path9of the valve100are in register. Each of the housing2and vessel4have corresponding mating surfaces12,13, which can be connected together in use in the manner described below. For this purpose, housing2is conveniently formed with a sleeve region2ihaving at one end an outwardly extending flange21, the base of the flange21comprising the mating surface12. At its other end, sleeve region2iis provided with a collar2p,the end face2qof which includes notches2f,2h,2d.The purposes of the collar2pand notches2f,2h,2dwill be described below. At its exit side11, the piston1extends from the valve100and the external surface is couplable to a downstream process, tubing, piping, vessel or the like.

Interconnecting piston1and housing2is an actuator5with locking mechanism5a.Actuator5also comprises a handle5bby means of which the valve100may be moved between open and closed states. Depending from handle5bis a cam mechanism5cfor enabling the piston to be displaced longitudinally relative to the housing2and actuator5. The entry side of valve100is covered with a sterilisable seal2a.In this embodiment of the invention seal2ais formed integrally and continually with housing2.

A cover member6is provided about the cam mechanism5cof the actuator5. Seal2acovers the mouth of the valve100at the entry side10and is formed continuously with the flange21. Seal2ais also connected to piston1in the matter described below. A junction2bbetween the flange21and seal2ais formed on the interior surface of the seal2a,the interior surface of the seal2abeing that surface facing the piston1. Junction2bcomprises a weakened point or a fracture line, formed for example by providing a reduction in thickness of the housing2in the area2c.When valve100is activated the seal2aand flange portion21separate at junction2bto provide a fluid passageway through the valve.

The individual components of the valve are shown, disassembled from one another, inFIGS. 1dto1k.

The valve100is opened by releasing locking mechanism5aand rotating handle5bin a clockwise direction. Locking mechanism5acomprises a release clip mechanism formed integrally with handle5band includes a tongue5j.Piston1has a radially projecting flange1cwith a recess1d.When the valve is closed tongue5jengages in recess1dthereby preventing rotation of the handle5bin either a clockwise or anti-clockwise direction. To release the locking mechanism5a,an external pressure such as a thumb force is applied to tongue5jto depress it thereby disengaging the tongue5jfrom recess1d.The actuator5is then free to rotate.

Rotation of actuator5causes piston1to move in the direction of the arrow inFIG. 1a,which causes the seal2ato rupture at the fracture line2bsince the piston1and seal2aare interconnected in the manner described below. This effectively withdraws the piston1plus seal2ainto the sleeve region2iof housing2away from the flange21thus removing the seal2afrom its position blocking the mouth10of the valve and thereby enabling fluid to gain entry into valve100as shown inFIG. 3d.

Thus when valve100is opened and as shown more clearly inFIG. 3d, fluid enters chamber7through the entry side mouth10and passes through collar2i, into the hollow centre that is the fluid path9of piston1.

A pair of O-rings8are positioned on the exterior surface of the piston1intermediate piston1and the collar region2iof housing2. The O-rings8seat in grooves1j(seeFIGS. 1hand1i) and provide an effective seal between piston1and housing2preventing any fluid passing. The O-rings8also provide resistance for the piston1as it moves, preventing piston1from moving too quickly and overshooting in either direction.

FIG. 1ashows a side section view of valve100coupled to an opening4cof a separate vessel or pipe4. Both the valve100and the opening4chave matching grooves2j(seeFIGS. 1aand1e) and4arespectively that encircle the circumferences of both coupling surfaces12,13, the coupling surface12of valve100being that which includes the sterilisable external surface of the seal2a. Washer3is placed intermediate the coupling surfaces12,13of the valve100and opening4cto seal them together. The washer3is formed with a circular formation3aon both of its planar surfaces. Formation3aseats in the grooves2jand4arespectively to locate the washer3. The valve100, washer3and vessel4can be secured together using a suitable fixing means such as a triclover clamp mechanism (not shown).

The means of interconnecting the piston1to the seal2awill now be described with particular reference toFIGS. 1a,1c,1e,1i,1j,3a,3dand9. Projecting upwardly from the substantially planar inner face of the seal2aare a set of four spaced-apart fingers2g.The free ends of the fingers2ghave a projection2mfacing radially outwards towards the collar region2iof the housing2. From the base section1bof piston1depends a circular skirt1fwhich is separated from the base section1bby a pair of opposed spacers1gthereby providing a pair of fluid flow apertures1iwhich constitute a fluid flow passageway to the interior fluid path9of the piston1.

On assembly of the valve100, the fingers2gare arranged to project into the skirt1funtil the projections2msnap over the edge of the skirt adjacent the base1band against the inner facing surfaces of the spacers1g.The fingers2gare resiliently outwardly biased so as to retain the projections2min engagement with the piston1. As an extra measure to retain the connection between the seal2aand the piston1, a plug2eis provided to be received between the bases of the finger2mand to further bias them into the radially outward position in which the seal2ais locked together with the piston1. Thus, the seal2ais permitted to move only on displacement of the piston1to which it is connected.

The matching interior surfaces of collar portion2iof the housing2and exterior surfaces of the spacers1ghave complementary ribs2kand recesses1erespectively to correctly guide and locate the piston1over the fingers2g.

It will be appreciated from the foregoing that on displacement of the piston1in the direction of the arrow inFIG. 1a, the seal2awhich is locked to the piston1will be torn along the weakened junction2buntil it separates from the flange21and will be withdrawn into the body of the valve100with the piston. Since the outer diameter of the skirt1fis less than the outer diameter of the base1bof the piston1, fluid will flow about the external surface of the skirt1fand through the apertures1ito the interior of the valve100and thence via the exit side11of the valve100to downstream processing.

FIGS. 2aand2care enlarged side section views of the actuator5and locking mechanism5aof valve100prior to and after activation respectively. The actuator5is connected to housing2by a snap-lock mechanism5gwhich comprises a pair of resiliently inwardly biased connectors5kwhich snap over the collar2pof the housing2. The actuator5and piston1are connected by means of a cam mechanism5c,comprising a pair of opposing outwardly projecting pins la on piston1which travel in a pair of shaped slots5don actuator5. Each of the shaped slots5dhas a first section5ewhich is substantially parallel to the longitudinal axis of the piston and a curved cam section5fwith a first region substantially perpendicular to the longitudinal axis of the piston and a second region curving more sharply toward the handle5bfor lifting the piston within the housing. The shaped slots5dare positioned diametrically opposite one another.

On assembly, and as best illustrated inFIGS. 1a,1b,1e,1i,1j,1kand9, the piston1is inserted through a top opening51on the actuator5, the skirt1kat the base1bof the piston leading, with the pins1afitting through recesses5mon the opening. The pins1apass through the recesses5mand engage in the first sections5eof the profile slots5d.The distance by which the piston1can be inserted into the actuator5is determined by the length of the first section5e.Once the pins1aengage with the bottom of the first section Se, the radially projecting flange1cof the piston1abuts the underside of handle5bof actuator5. The piston1and actuator5are then rotated relative to one another so that the tongue5jof the locking mechanism5aengages in the recess1don flange1c,thereby preventing further rotation. This position comprised the state of the valve in which it is supplied closed and ready for use, herein referred to as the “ready state”.

In use and in order to open the valve100, the locking mechanism5ais released as described above by depressing the tongue5j.Once the locking mechanism5ais fully released, handle5bcan be rotated. The rotation of actor5causes pins1ato move out of the lock position shown inFIGS. 1aand2aand into and along the curved cam section5f.The transition from the closed, ready for use, state to the open, deployed, state will be described in more detail below.

The curved cam section5fhas two regions. Of these, the first is substantially perpendicular to the longitudinal of the piston1but has a gentle curve toward the handle5b.Therefore, as the rotation of the handle5bproceeds, the pins1amove along this perpendicular region causing the piston1to travel along its longitudinal axis, thereby causing the seal2aconnected to the opposite end of the piston1to shear and break at junction2b.The gentle curve assists in the tearing away of the seal as the piston travels along its longitudinal axis it causes the piston to lift gently away from the flange21of the sleeve portion2ias rotation continues. In the next stage of opening the valve100, the now broken-away seal2ais moved away from the flange21by withdrawing it together with the piston1. This is achieved by continued rotation of the handle5bwhich moves the pins1ainto the following, more steeply curved path of the cam region of the curved cam section5f.As the pins1amove along this path the piston1travels along its longitudinal axis in a direction away from the flange portion2j.At the end of the rotation of the handle, the seal2ahas moved away from its position blocking the entry side10and fluid communication between the vessel4and the valve100is achieved as described above.

FIGS. 2band2dare plan views of the position of the actuator5before and after actuation of the valve100respectively, that is to say, with the valve closed end open.

As described above the substantially perpendicular region of the curved cam section5fis in fact not perfectly straight, but is ideally formed with a gradual slope to assist breakage of the seal2a.In one preferred arrangement, the initial rotation of the handle5bfrom 0° to about 56° accomplishes breakage of the seal2a,whilst the sharply sloping cam region is from about 56° to about 80°.

Referring now toFIGS. 1a,1dand1k,the counter rotation of handle5bis prevented by stop means comprising a pair of opposing resilient teeth5ion the actuator5remote the handle5b(only one tooth is visible in the drawings) and two sets of notches2d,2fand2hon the upper surface2qof the collar2pof the housing2. On assembly of the valve100, the piston and actuator5are in a relatively locked position and rotation of the actuator5is prevented. The teeth5iengage in this state with first notches2f.There are markings2n,2r,6bprovided on the outer surface of the cover6and housing5(seeFIGS. 1dand1f) which are arranged so that when they are aligned, they indicate that the valve100is closed. Valve100is assembled and presented to the user in this ready, closed state, with each tooth5iengaged in a notch2f.When the valve is in this state, the tongue5jof actuator5is engaged with recess1dof the piston and the piston pins1aare engaged at the base of first section5aof the slots5d.In this position, the valve is closed and the tips of the arrowheads2nof housing2and6bof cover6face each other to indicate that the valve is closed. In the first stage of operating the valve, tongue5jis depressed as described above to release it from recess1d,thereby enabling handle5bto rotate, bringing teeth5iout of notches2fand into notches2h.In this intermediate position the valve is still closed, since although pins1ahave displaced slightly into the first region of the cam section5fof the slots5d,they have not moved sufficiently to begin to tear open seal2a.Nevertheless, the arrow tips2nand6bwill now have moved apart by a distance equal to the distance between the bases of notches2fand2h,and this gives an indication to the user that it should not be assumed that the seal is intact, but that it should be checked before continuing. Since the teeth5iare engaged in notches2hin the intermediate state, the valve will remain in this state until the user turns the handle sufficiently forcefully to pull the teeth5iout of notches2h.The next step opens the valve. It is effected by further rotating handle5bto cause the teeth5ito ride over and out of notches2hand travel into notches2d.When notches2dare reached, the valve is fully open, since the pins1ahave travelled to the end of cam section5f,tearing open the seal and lifting is free of the open first end of the valve.

The notches2d,2fand2hhave a sloped side that enables the teeth5ito easily slide out of each notch,2d,2fand2hin one direction only. Movement in the reverse direction is prevented as the tooth abuts the sheer face of the notch and cannot travel over it.

Referring toFIGS. 1hand1i,there are shown two possible variations of the exit side11,110of the piston1. InFIG. 1h,this end11is formed with external ribbing to enable it to be connected to another enclosure, be it vessel or line. In theFIG. 1imodification, the exit end110is formed with a coupling flange110f,110gto enable it to be connected to a mating surface, for example to a surface of another vessel. This is an arrangement comparable to the coupling flange2bof the housing2.

As best seen inFIGS. 1fand1g,the cover6is formed as a sleeve sized to cover the exteriors of the housing and cam mechanism5cof actuator5. A pair of opposed open slots6aare provided at the base of cover6. When the valve is assembled, these slots supply a clearance for the connectors5kwhich snap over the collar2pof the housing. The slots6aalso provide a sufficient flexibility to the cover so that finger pressure exerted on the base of the cover at the points which are 90 degrees displaced from the slots6aenables the cover to flare sufficiently to assist its release from the housing, subject to the material of the valve being capable of sufficient deformation to allow this. Recess6con the upper end of the cover6provides a clearance for the tongue5jto be depressed into when that tongue is released from the piston recess1dto allow the valve to be opened.

FIGS. 3aand3bare side section views and plan views of the seal2aof valve100before opening.FIGS. 3cand3dare corresponding views after opening. The seal2ais connected to the piston1using the snap-lock described above. This configuration enables the seal2ato withstand pressures which are a multiple of the normal pressure of a steam sterilising fluid load without rupturing seal2aat the junction2b.

FIGS. 4aand4bshow a second embodiment of the valve200of the invention. Valve200operates as previously described in relation to the first embodiment. In this case valve200is coupled to an opening40cof a separate vessel or pipe40. The coupling surfaces212,413of both the valve200and the opening40chave a projecting rim20aand40arespectively encircling the outer edge of the surfaces. Each surface also has a groove2jand4arespectively encircling the circumference of the surface intermediate the seal2aand the projecting rim. A washer3is placed between the two surfaces to provide a seal between them and the washer has complementary ring formations30asized and shaped to fit within the grooves in the coupling surfaces.

FIGS. 5aand5bare views of a third embodiment of the valve300of the invention, which is a modification of the second embodiment. Valve300is adapted to connect at its exit side to an opening on a pipe or vessel in similar fashion to the connection at the entry side. The exit side of the piston110eincludes a connecting surface with a projecting rim110gencircling its outer edge and a groove110fto receive the washer in the same manner as described in relation to the entry side of the valve.

There is shown inFIG. 6aa fourth embodiment of a valve400, which is a modification of the first valve embodiment. Valve400is modified to connect at it's exit side to an opening on a pipe or vessel in a similar fashion to the third embodiment of the valve.

FIG. 7is a side section view of a variant seal section of a valve prior to activation.FIG. 7ais an enlarged view of the ringed portion ofFIG. 7. These figures show a double mating seal edge11as an alternative, effective seal between the piston1and the housing2. The double seal edges11are formed during the moulding process of the individual components of the valve. The seal edges11are formed as radial projections encircling the external surface of the piston1. The projections11provide an effective seal when the piston1is inserted into the housing2. The projections also provide resistance for the piston1when it moves preventing overshooting and other associated problems.

FIGS. 8ato8iare a series of side sectional views of different openings301to309to which a valve according to the invention can be coupled. Also shown are different types and sizes of washers301ato309awhich can also be used to facilitate sealing between the valve and the openings301bto309b. Many other shapes and configurations of the valve, opening and washer are possible within the scope of the invention.

Referring now toFIGS. 9ato9g, there are shown the steps taken in the assembly of the valve100. The O-rings8are placed in recesses provided on the external surface of the piston1. The piston1is then inserted into the actuator5(step1001), The piston1is rotated within the actuator5to allow the locking mechanism (not shown) engage with the recess in the projecting flange of the piston (step1002). Simultaneously the cover6is placed over the housing2(step1003). The piston1and actuator5combination are inserted into the assembled housing2/ cover6(step1005), so that the housing2and actuator5engage by means of the snap-lock mechanism and the seal (not shown) and piston1also connect by means of their snap-lock mechanism (step1006). Once the individual components are connected to each other the cover6is pushed up over the housing2to cover the cam mechanism on the actuator5(step1007). A plug insert2eis inserted into the piston100from the exit side down to the entry side to engage between the fingers2g(not shown) connecting the seal and the piston1(step1008). The closed valve can then be bagged or packaged in some convenient way and sterilised. Optionally, other components useful in effecting a transfer may be packaged with the valve.

FIGS. 10a,10band10care a plan view, a side section view and a sectional view of a fifth embodiment of a single use valve500according to the invention. Valve500operates in the same manner as the previous embodiments of the valve, however the way in which the piston1is connected to the seal2ais different. In this embodiment, the piston1and seal2aare connected by means of a saw-tooth configuration1c.The saw tooth fit also enables the seal2awithstand pressures which are a multiple of the normal pressure of a sterilising fluid load without rupturing seal2aat the junction2b.

FIG. 11is a side section view of a sixth embodiment of a single use valve600. The actuator5has a locking mechanism51, which differ to that of the other embodiments of the value. Actuator5is connected to the housing2by means of a snap-lock mechanism6d.The piston1is connected to the actuator5by means of a screw thread mechanism11, where the interior surface of the actuator5and the exterior surface of the piston1are provided with mutually engageable screw threads.

Actuator5is biased to rotate and the locking mechanism51comprises a locking pin51athat inserts into piston1through actuator5thereby preventing rotation of actuator5against the bias. When the locking pin51ais withdrawn, actuator5is free to rotate under the bias and rotates a number of degrees which is an insufficient distance to rupture the seal2abut which is sufficient to prevent reinsertion of the locking pin51a.Thus if there is no locking pin51apresent, this provides a warning to a user that the valve may be compromised.

Once the pin is withdrawn, the actuator5is rotated further to rupture seal2a.The seal2ais connected to the piston1by means of the saw-tooth configuration1cdescribed above in connection withFIGS. 10ato10c.As the actuator5is rotated, the piston1moves further from the entry side of the valve600rupturing the seal2aand enabling fluid to gain entry to the valve600. The distance the seal2atravels from the entry side of the valve600is determined by the degree of rotation of the actuator5.

A limiting mechanism for preventing the piston from travelling too far in either direction is also provided. The exterior surface of piston1has a detent12remote the entry point of the locking pin5a.Detent12comes into abutment with surface14when piston1travels towards the sealed entry side of valve101preventing further movement in that direction. Similarly detent12abuts surface13when piston1travels away from the sealed entry side of valve101preventing further movement in the direction away from the sealed entry side of valve101.

Referring now toFIGS. 12a,12band12c,there is shown an embodiment of a multi-use valve700according to the invention. The seal21ais provided as a replacable attachment. Seal21ais secured to the valve as follows; seal21aattaches to piston1by means of a saw-tooth configuration1aand a collar portion (not shown) is clipped in place using clip-on mechanism21. The collar portion is further secured in position when attached to opening4. Seal21aalso acts as a washer between the valve700and opening4.

In use valve700operates in the same way as the single-use valves100to600respectively. The actuator5and locking mechanism5aare provided as a clip release mechanism as described for single-use valve100. Once the locking mechanism5ais released, the actuator5is free to rotate. The piston1travels in a direction away from the sealed entry side of the valve700by means of pins30cand30dwhich follow profiled slots (not shown) as for single-use valve100. As piston1travels in a direction away from the sealed entry side of the valve700, the seal21aruptures at fracture line21band moves with the piston1enabling fluid to gain entry to the valve700.

FIG. 13is a further embodiment of a multi-use valve800according to the invention connected to an opening4. The actuator5and locking mechanism52of valve800differ from that of valve700ofFIG. 12b.Actuator5is attached to piston1remote the sealed entry side of the valve800by means of a screw thread mechanism. The inner surface of actuator5has a first screw thread, the exterior surface of piston1has a second screw thread and both screw threads are mutually engaging. The actuator5is also secured to housing2by means of securing fitting15. Securing fitting15is attached to the actuator5and piston1remote the housing2forcing the actuator5into contact with the housing2at the surface remote the securing fitting15.

Locking mechanism52is provided as a locking pin52bthat inserts into piston1through handle6bof actuator5. Locking pin5bis removed completely to operate valve103. When locking pin5bis removed, actuator5is free to rotate.

As actuator5rotates piston1is forced to travel in a direction away from the sealed entry side of valve800. The seal21atravels with piston1causing seal21ato rupture at fracture line21benabling fluid gain entry to the valve800.

The piston1, housing2, actuator5and locking mechanism5of multi-use valves are generally manufactured from a heavy duty durable material such as stainless steel. Alternative materials can also be used. Sealing O-rings8are used as the piston seal when the piston1and housing2are formed from stainless steel. The seal21aof a multi-use valve can be made from any suitable material known to a person skilled in the art including plastics, foil and rubber or rubbery-type materials including flexible and inflexible materials. The seal21ais replaced when required by removing the old ruptured seal and inserting a new seal into position, snapping it securely in place in the saw-tooth configuration between the piston1and seal21a.Any one seal21amay be used more than once in the multi-use valve, with appropriate cleaning and resterilisation. However it is not recommended to use a seal more than five times in order to maintain the integrity of the system. Alternatively the seal21acan be replaced after each use once the seal is broken.

One example of how the valve of the invention may be used in practice will now be described. In this example, a first vessel is to be connected to a second vessel by means of a tubing. The tubing is provided with a valve according to the invention at each of its ends. The tubing with the valves attached at either end is placed in a bag and sterilised, for example by steam, gas, radiation or any other suitable means. In a first step, the bag is opened and one of the valves is removed, thereby exposing the external sealing surface of that valve to environmental contamination. This valve is coupled to the first vessel and the first vessel is then steam sterilised, thereby also resterilising the exposed face of the valve. This first vessel with attached tubing is next transferred to the site of the second vessel. There, the valve on the opposite end of the tubing is released from the bag and connected to the second vessel in like manner as described in relation to the first valve and first vessel. The second vessel and attached valve are then steam sterilised. Now, both valves may be opened providing a sterile fluid path between the first and second vessels.

In operation of the valve of the invention, the valve is pre-sterilised, for example by gas, gamma ray or steam sterilisation, prior to use. At this stage, it is in its closed position. Once sterilised, the valve can be connected to any desired opening of a pipe or vessel. In connecting the valve to the opening the external surfaces of the valve including the exterior sealed entry side of the valve is exposed to the atmosphere thus sterility is compromised. Once the valve is connected, the vessel or pipe to which it is attached is sterilised, enabling the external connecting surface of the valve to be resterilised. Once the connecting surface of the valve has been resterilised the valve can be opened when required.

The valve or any of its parts may be fabricated from any suitable material including plastics materials (such as polypropylene and the like) and metals or ceramics. Plastics are particularly preferred for the single use valve.

Whilst the valve has been specifically described with reference to a seal which is torn away from a sealing interface and withdrawn into the body of the valve, it will be appreciated that other arrangements will be possible within the scope of the invention. For example, the piston may be arranged to drive the seal out of the valve to unblock the fluid passageway. Likewise, the piston may be arranged to rupture or break the seal by cutting it open and bending the torn parts out of the fluid path. Many different forms of seal will be possible within the scope of the invention, including thin or thick membranes, foils, flexible and inflexible materials.

It will be understood that the invention is not limited to specific details described herein which are given by way of example only and that various modifications and alterations are possible without departing from the scope of the invention, as defined in the appended claims.