GB2522292A

GB2522292A - Fluid transfer devices

Info

Publication number: GB2522292A
Application number: GB1416555.9A
Authority: GB
Inventors: Christian Mide; Marius Andresen; Rolf Blomvã Gnes; Kevin Geers
Original assignee: Conceptomed AS
Current assignee: Conceptomed AS
Priority date: 2013-11-06
Filing date: 2014-09-19
Publication date: 2015-07-22
Anticipated expiration: 2034-09-19
Also published as: GB201416555D0; GB2522292B; GB201319628D0

Abstract

A fluid transfer device 12 comprises a fluid chamber in communication with a fluid transfer tip. A safety cover 4 is resiliently biased to a position uncovering the fluid transfer tip but moveable to cover the fluid transfer tip. A lever member 14 is pivotally mounted to the fluid chamber and operable to move the safety cover 4 against the resilient bias so as to cover (or re-cover) the fluid transfer tip.

Description

Intellectual Property Office Application No. GB1416555.9 RTTVI Date:5 March 2015 The following terms are registered trade marks and should be read as such wherever they occur in this document: Epi Pen (registered) Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo Fluid Transfer Devices The present invention relates to fluid transfer devices having means controllably operable to cover or re-cover a fluid transfer tip.

In a medical setting it may be necessary or desirable to transfer fluid to/from a subject for a variety of reasons. For example, a hub carrying a needle or other cannula may be connected to a fluid transfer tip and used to draw blood from a vein or to infuse fluid substances i.e. intravenous (IV) therapy. In another example, a fluid transfer tip may be connected directly to a cannula for the addition or removal of fluid to/from a variety of bodily cavities, organs or vessels. For instance, the tip may be connected to a catheter to drain urine from the bladder or kidney, to remove fluid from an abscess, to extract liquid from joints or cysts, or to administer breathing gases through a tracheal tube. A typical endotracheal tube includes a cuff inflation tube with a connector for a syringe tip to enable inflation to seal the trachea and bronchial tree against air leakage and aspiration of fluids. A tracheotomy tube or urinary tract catheter might also use a cuff system with a hub for connection of a syringe or other device to inject fluid to inflate a cup or balloon that holds it in place.

Fluid injections using a syringe are one of the most common healthcare procedures in the world. Injection devices such as syringes may be provided with a needle e.g. for intramuscular or subcutaneous injections, or they may be needleless e.g. a prefilled syringe connected to a catheter or IV port to provide continuous therapy and/or flushing. Prefilled injection devices for administering a vaccine may simply comprise a single dose pouch and a needle so that there is no risk of needle re-use.

After using a device to transfer fluid to/from a subject, the tip or connected hub with its needle, catheter or other cannula may be exposed before/during disposal and this can potentially expose healthcare workers to the risk of infection.

For example, even a blunt cannula can drip bodily fluid until it is covered or placed in a bin. Devices involved in high risk procedures include IV cannulae, winged steel needles (known as butterfly needles), hypodermic needles and syringes, and phlebotomy needles. There is a particularly high risk of injection when the tip carries a needle and causes a needlestick injury. It has been found that needlestick injuries can often happen while resheathing or recapping a needle. In the EU, Directive 2010/32/EU on the prevention of sharps injuries in the hospital and healthcare sector has banned the practice of needle recapping. In the UK, regulations that implement the Directive 2010/32/EU were enacted into law in May 2013. Recommended practice is to dispose of sharps immediately after use.

Some fluid transfer devices incorporate safety-engineered protection mechanisms e.g. safety needles. These devices have a built-in safety feature to reduce the risk of a sharps injury before, during or after use. Devices can be passive or active. Passive devices have a safety mechanism that is automatically activated after use, such as when a cannula is withdrawn from a patient's vein, for example a needle retracting or blunting mechanism. Active devices need to be manually activated by a user; examples include sliding or hinged needle shields attached to a needle hub for use with disposable syringes.

Even when healthcare workers are provided with safety-engineered devices, if the mechanism is not quick and easy to use then they may choose not to use it and a needle or other contaminated tip may be left exposed before/during disposal.

For example, a user may choose not to activate a sliding or hinged needle shield if it is perceived that manual operation requires the user to bring his/her hand closer to a potentially contaminated needle.

There remains a need for improved safety in fluid transfer devices.

According to a first aspect of the present invention there is provided a fluid transfer device comprising: a fluid chamber in communication with a fluid transfer tip; a safety cover moveable to cover the fluid transfer tip; and one or more lever members pivotally mounted to the fluid chamber and operable to move the safety cover so as to cover (or re-cover) the fluid transfer tip.

It will be appreciated that in such a device the pivotal movement of a lever member is transformed into movement of the safety cover, rather than the safety cover moving directly under a manual force or its own spring bias. Independent movement of the lever member(s) therefore controls movement of the safety cover.

This may be achieved, for example, by the lever member(s) physically acting on the safety cover to move it into a position covering (or re-covering) the fluid transfer tip.

The lever member(s) are preferably separate components that only couple to the safety cover when operated to transmit movement thereto.

A benefit of operating a lever member so as to move a safety cover over a fluid transfer tip is that a user does not need to come into contact with the safety cover itself. Rather than manually moving the safety cover and therefore coming close to a potentially contaminated fluid transfer tip, a user can take advantage of the dedicated lever member(s) to activate the safety cover. Furthermore, such a fluid transfer device may have a much improved ergonomic design in which a user handling the fluid chamber is able to operate the lever member(s) in a convenient single-handed operation. Whereas prior designs may have required a user to hold a fluid transfer device e.g. syringe in one hand and manually manipulate a needle safety cover with the other hand.

A further advantage of using the pivotal motion of a lever member to operate the safety cover is that the pivotal motion may be readily transformed into a pivoting movement of the safety cover, for example where the safety cover is hinged.

Accordingly the safety cover may be pivotally connected to the fluid transfer tip.

This is convenient for swinging a safety cover across from a position lateral of the fluid transfer tip, where it is less likely to interfere with handling of the fluid transfer device. Although the lever member(s) may operate to slide a safety cover forwards or backwards along the fluid transfer tip, in such an arrangement the safety cover may interfere with a user's freedom when handling the device.

Furthermore, a particular benefit of operating a lever member to move the safety cover is that the lever member can be arranged to apply a particular level of force, for example by amplifying the pivotal motion input by a user manually operating the lever. For example, the lever member(s) may amplify a relatively light touch so as to provide a strong snap action for the safety cover.

In one set of embodiments the pivotal connection of the safety cover may comprise a hinged connection to the fluid transfer tip, for example being connected by a living hinge. This may enable integral moulding in a single plastics component. However, to enable the lever member(s) to interact more easily with the safety cover, in addition to the hinged connection the safety cover may comprise an actuating portion extending backwards from the hinge point to be acted upon by the lever member(s).

Before use, the fluid transfer device may have the safety cover moved away from the fluid transfer tip, for example pivoted away from the tip. In some examples the lever member(s) may be operable to move the safety cover so as to uncover the fluid transfer tip. In other examples the safety cover may automatically uncover the fluid transfer tip. The safety cover may only be intended to be moved into a covering position during a final use step, after a fluid transfer procedure has been carried out. Once the tip has been covered (or re-covered) it may not be expected to be used again, e.g. to prevent contamination. A removable cap or sheath may separately cover the fluid transfer tip before use.

In a first set of embodiments the safety cover may be moveably connected to the fluid transfer tip and resiliently biased to an open position uncovering the fluid transfer tip. This means that the safety cover is automatically biased away from the fluid transfer tip without requiring a user to take action to uncover the tip. A resilient bias, for example provided by a spring member, may tend to move the safety cover into this open position. It is possible that the safety cover may be connected to the fluid transfer tip so as to move substantially linearly along the tip but, as mentioned above, this may require the fluid transfer device to accommodate longitudinal motion of the safety cover as it is moved backwards to uncover the tip. Rather it is preferable that the safety cover be pivotally connected to the fluid transfer tip. Thus in its open position the safety cover may be biased to a positioned where it is pivoted away from the fluid transfer tip. In one set of embodiments, the safety cover is pivotally connected to the fluid transfer tip and resiliently biased to an open position in which it is pivoted away from the tip. For example, a spring member may be arranged between the safety cover and the fluid transfer tip to resiliently bias the safety cover to the open position. In some examples the safety cover may be resiliently biased by a material resilience rather than a separate spring member.

The lever member(s) preferably operate to move the safety cover against the resilient bias to a closed position covering (or re-covering) the fluid transfer tip.

Pivotal motion of the lever member(s) may conveniently be converted to pivotal motion of the safety cover, where the safety cover is pivotally connected to the fluid transfer tip. Whereas a user directly operating a safety cover may find it difficult to apply sufficient force to overcome the resilient bias, a lever member is able to amplify a manual input force so as to move e.g. pivot the safety cover against the resilient bias.

Where a pivoting safety cover is resiliently biased to such an open position, the lever member may comprise a surface arranged to push against the safety cover to pivot it against the resilient bias into a closed position. This is preferably facilitated by the safety cover comprising an actuating portion arranged to be acted upon by the lever member(s). Thus in a set of embodiments the safety cover is pivotally connected at a pivot point, the safety cover comprising a cover portion extending forwards of the pivot point and an actuating portion extending backwards of the pivot point to be acted upon by the lever member(s). Accordingly the actuating portion of the safety cover is arranged on an opposite side of the pivot point to the cover portion of the safety cover. Thus as the lever member is pivoted towards the fluid chamber of the fluid transfer device, the actuating portion may be pushed to move the safety cover into alignment with the lever member and therefore pivot the cover portion towards the fluid transfer tip, against the resilient bias.

When the lever member(s) are operable to move the safety cover from an open position to a closed position in which it covers (or re-covers) the fluid transfer tip, the device preferably comprises means for locking the safety cover in its closed position. This may be particularly desirable in embodiments where the safety cover is biased to the open position. This can ensure that the fluid transfer tip is permanently covered (or re-covered) and therefore cannot be reused. This may be particularly important where the fluid transfer tip includes a needle or has a needle hub connected. In some examples, operation of the lever member(s) may cause it to be locked in a final position holding the safety cover in its closed position. For example, locking means may be arranged between the lever member(s) and the fluid chamber. Alternatively, or in addition, the safety cover and/or fluid transfer tip may include means for locking the safety cover in its closed position once it reaches its closed position. Preferably the locking means acts automatically, rather than requiring manual activation. A snap-lock may be provided for the lever member(s) and/or safety cover to hold the safety cover in the closed position.

Where the safety cover is pivotally connected to the transfer tip and arranged to pivot laterally, the safety cover may be open on a side facing the fluid transfer tip and otherwise substantially closed. For example, the safety cover may have a generally cylindrical form, with a cross section that is circular, square, rectangular or otherwise shaped, but with a side facing the fluid transfer tip being open such that the tip becomes enclosed by the cylindrical form when the safety cover is moved to its closed position.

The fluid transfer tip may be any tip that becomes contaminated with fluid after use such that it is desirable for the tip to be easily covered or re-covered once a fluid transfer procedure has been completed. In one set of embodiments the fluid transfer tip may be needleless, for example the fluid transfer tip of a prefilled flush syringe. In another set of embodiments, the fluid transfer tip may include a needle.

The needle may be integrated with the tip or permanently connected thereto, for example the injection needle of a prefilled single dose pouch or the needle of an auto-injector such as an EpiPen. In other embodiments the fluid transfer tip may include a needle hub separably connected thereto. In such embodiments the safety cover may be moveably connected to the needle hub, e.g. pivotally connected to the needle hub, so that the needle hub and safety cover are both part of a component separable from the fluid transfer tip. Such a needle hub may be connected to the fluid transfer tip of a variety of different devices such as a syringe or catheter connector.

A needle hub that has a pivoting safety cover arranged to be controllably moved, e.g. by the pivoting lever member of a fluid transfer device, is considered novel and inventive in its own right. Thus according to a further aspect of the present invention there is provided a hub comprising a needle for transferring fluid to/from a fluid transfer tip connected thereto, the hub comprising a tapered internal surface to form a friction fit with a corresponding fluid transfer tip, and a safety cover pivotally connected to the hub at a pivot point, the safety cover comprising a cover portion extending forwards of the pivot point to cover the needle and an actuating portion extending backwards from the pivot point that is operable to provide pivotal movement of the safety cover.

Such a needle hub may provide benefits over simple hinged cover designs as the see-saw arrangement means that the actuating portion is on the opposite side of the pivot point to the cover portion. In some examples, a user can operate the actuating portion without touching the cover portion. In other examples, the actuating portion can be operated by a lever member. The needle hub provides flexibility in that the safety cover can be operated in different ways.

In a set of embodiments the safety cover is resiliently biased to an open position where the cover portion is pivoted away from the hub to uncover the needle. The hub may, for example, comprise a spring member arranged to resiliently bias the cover portion away from the needle. Or the material construction of the safety cover may provide a resilient bias. The see-saw arrangement of the safety cover can then be used to pivot the cover portion against the resilient bias when it is desired to cover (or re-cover) the needle. Although the safety cover may be operated directly by manual force, preferably the actuating portion is operated by a lever member so as to amplify the manual force and more easily overcome the resilient bias.

Preferably the hub comprises means for locking the safety cover in a closed position where the cover portion covers the needle. For example, the cover portion may include means for gripping onto a needle. A click-fit may be used to provide audible feedback when the safety cover is locked to the needle. As is described above, this means that the needle stays covered even if the safety cover is released. In embodiments where the safety cover is resiliently biased open, either the locking means is strong enough to hold the cover portion against the resilient bias and/or the resilient bias is disabled when the safety cover is moved to the closed position.

The hub optionally includes a removable needle sheath. The needle sheath may be accommodated inside the safety cover. Especially in embodiments where the safety cover is resiliently biased to an open position, the sheath may cover the needle until removed by a user e.g. at the point of carrying out a procedure.

The hub with its friction fit may comprise a standard Luer Slip or Luer Lock connection. To provide a Luer Lock connection the hub may optionally include a an inwardly threaded collar. Although standard Luer Slip or Luer Lock connections use a male tapered tip that fits inside a female hub, it is envisaged that this could be reversed and the fluid transfer tip could be a female part having an internal taper to form friction fit with a corresponding male hub.

In a preferred set of embodiments the hub is designed to provide a tapered friction fitting in combination with an additional means enabling the hub to be locked in position when connected to a fluid transfer tip by the friction fitting. In a set of embodiments the hub further comprises an outer rim or thread to enable it to be positively engaged when connected to a fluid transfer tip by the friction fitting.

Preferably the outer rim or thread is spaced from a base of the hub by a skirt portion. The skirt portion can provide space for a lever member to rotate into position with a screw thread mounted on the lever member locking the hub with a screw fit in addition to the friction fitting. This may be particularly suitable for high pressure fluid connections e.g. when transferring more viscous fluids.

Embodiments may also include a fluid transfer device comprising a fluid chamber in communication with a fluid transfer tip and a hub as described above connected to the tip. In addition to the novel hub design, the device may comprise a lever member pivotally mounted to the fluid chamber and operable to move the safety cover so as to cover (or re-cover) the fluid transfer tip. As has already been mentioned, the lever member may be arranged to push against the actuating portion of the safety cover so that it is pivoted towards a closed position where the cover potion covers over the needle. In addition to the lever member acting to move the safety cover, the lever member may optionally provide an additional function of loosening the friction fit between the hub and the fluid transfer tip. Thus, in a set of embodiments, the lever member comprises a front surface moveable between a first potion proximal to the fluid chamber and a second position spaced from the first position towards a distal end of the fluid transfer tip so as to release the friction fit.

As well as loosening the friction fit of the hub, movement of the lever member may also act to push away the hub from the fluid transfer device, for example when it is desired to discard a needle hub after use. It is an advantage of the lever effect that a user can more easily apply sufficient force to overcome the friction fit of the hub. However, the applicant has recognised that there may be a risk of the hub being forcibly disconnected and shooting away from the device. In order to prevent this from happening, the device may further comprise catch means arranged to catch the hub after it has been released from the friction fit by the front surface of the lever member moving towards the second position. The catch means may be provided by the lever member itself. In order to release the catch means so that the hub can fall away from the device, the lever member may be pivoted back manually or released so as to pivot under a bias force. For example, the lever member may be resiliently connected to the fluid chamber and spring biased so as to move its front surface back to the first position.

It is mentioned above that the hub may comprise an outer rim or thread to enable it to be positively engaged, i.e. locked, when connected to a fluid transfer tip, in addition to the friction fit. In such embodiments, a screw thread may be mounted on the lever member so as to lock the hub to the fluid transfer tip by a screw fit in addition to the friction fit. Preferably the lever member is resiliently biased so that its screw thread is positioned to form a screw fit with the hub. When the lever member is pivoted against its resilient bias, this releases the screw fit with the hub, which may then be disconnected by the lever member operating to release the friction fit. This two-stage connection can ensure that a separable needle hub is firmly connected to the fluid transfer tip. Alternatively, or in addition, the fluid transfer tip may comprise means for gripping the hub in a locked position. This may include a snap-fit connection, latch means, one or more gripping fingers, etc. that positively engage, i.e. grip the hub when it is connected to the tip. The fluid transfer device may take the form of a syringe, blood collection tube or hose connector.

In the first set of embodiments described above, the safety cover is resiliently biased to an open position where the fluid transfer tip is uncovered. The applicant has recognised that it may not always be convenient for the safety cover to be biased to an open position before use, particularly as this may cause the safety cover, and any corresponding needle hub, to take up a lot of space and potentially involve additional packaging. One solution could be to package the safety cover, or corresponding needle hub, with the cover portion pivoted down against the resilient bias to take up less space -the safety cover would then pop into an open position as soon as the packaging is released. Even so, an open safety cover may be found cumbersome when a user is manoeuvring a fluid transfer device into position, especially when carrying out a fluid transfer procedure in a confined space. It would be desirable for a safety cover to allow for pivotal movement between open and closed positions while also adopting a more compact configuration prior to use.

In a second set of embodiments the safety cover is moveably connected to the fluid transfer tip and bi-stable between a closed position in which it covers the tip and an open position in which the tip is uncovered. By providing such a bistable arrangement the safety cover can be flipped between open and closed positions. A resilient bias or latch is not required to move the cover into an open or closed position, or to hold the cover in a particular position. Once a lever member is operated to push the cover out of one stable position, it automatically flips to the other position. Instead of a manual force being applied directly to the safety cover, the operation of the lever member(s) ensures that the safety cover moves controllably between positions. Preferably the lever member(s) is/are operable to move the safety cover between the open and closed positions. A lever member may be manually returned between operations, but is preferably resiliently biased to return after each operation.

The bi-stable safety cover may move linearly, but preferably the safety cover is pivotally connected to the fluid transfer tip. This can make it easier for pivotal movement of the lever member to be translated into pivotal movement of the safety cover. For single-handed operation, it is preferable for the lever to be squeezed towards the device in order to move the safety cover between positions. In a set of embodiments the lever member operates to move the safety cover between the open and closed positions as it pivots towards the fluid chamber. Preferably the lever member comprises a first actuator arranged to push the safety cover so as to -10-move it from the closed position to the open position. Thus operating e.g. squeezing down the lever member can operate to flip the safety cover open. The lever member may be manually returned, but preferably the lever member is resiliently biased so as to return e.g. automatically pivoting away from the fluid chamber again.

Once a fluid transfer procedure is complete, it is desirable to operate e.g. squeeze the lever member again so as to close the safety cover in another single-handed operation. Preferably the lever member comprises a second actuator arranged to push the safety cover so as to move it from the open position to the closed position. The first and second actuators may be provided by the same pad or they may be separate parts. It will be appreciated that the first and second actuators only need to apply an impulse to the safety cover to push it out of one stable position to that it moves to the other. The actuators do not need to push through the whole range of movement of the safety cover. Each actuator may be little more than a protuberance arranged on the lever member.

An advantage of the bi-stable safety cover is that the device can be packaged and transported with the safety cover stably adopting the closed position.

In one set of embodiments the device may comprise a seal over the fluid transfer tip when the safety cover is in the closed position, the seal being arranged to be broken when the safety cover first moves to the open position. Such a seal can help to ensure sterility.

The safety cover may be flipped between closed, open and closed positions multiple times, for example where a fluid transfer tip is re-used in more than one procedure. However, to avoid contamination, especially in medical applications, it may be desirable for the safety cover to remain in the closed position after the device has been used. The device may therefore comprise means for locking the safety cover in the closed position. This may be particularly important where the fluid transfer tip includes a needle or has a needle hub connected. In some examples, double operation of the lever member(s) may cause it to be locked so that the safety cover can only be moved once from a closed position to an open position (e.g. ready for use) and then once back to the closed position (e.g. following use). The locking might comprise disablement of the lever member in a permanent member. Alternatively, or in addition, the safety cover and/or fluid transfer tip may include means for locking the safety cover as it moved into the closed position. Preferably the locking means acts automatically, rather than -11 -requiring manual activation. For example, a snap-lock may be provided for the lever member(s) and/or safety cover to hold the safety cover in the closed position.

Such a bi-stable safety cover may find use in a range of fluid transfer devices having fluid transfer tips that carry a needle or tips that are needless. The lever member is easily operated, e.g. in a single-handed operation, to flip the safety cover between open and closed positions. A fluid transfer tip can therefore be exposed for use and covered (or re-covered) quickly after use. This might be particularly useful where the fluid transfer device is an auto-injector e.g. EpiFen designed for multiple doses, for instance with a needle being changed between uses. In other examples the fluid transfer device may be an injection device with a needle integrated into the fluid transfer tip or a needle hub separably connected to the fluid transfer tip.

In a set of embodiments the fluid transfer tip includes a needle. In another set of embodiments a needle hub is separably connected to the fluid transfer tip. A needle hub taking advantage of a bi-stable safety cover is considered novel and inventive in its own right. Thus according to a further aspect of the present invention there is provided a hub comprising a needle for transferring fluid to/from a fluid transfer tip connected thereto, the hub comprising a tapered internal surface to form a friction fit with a corresponding fluid transfer tip, and a safety cover pivotally connected to the hub, wherein the safety cover is bi-stable between a closed position in which it covers the needle and an open position in which the needle is uncovered.

Such a hub can conveniently be connected to the fluid transfer tip of various different fluid transfer devices, and operated manually or by a lever member. As the safety cover flips from the open position to the closed position (or vice versa) when an impulse is applied, without needing to be pushed through its movement, a user need only apply a light touch. This reduces the risk of a user pressing down on the safety cover and coming into contact with the needle.

In a set of embodiments the hub comprises a seal containing the needle and the safety cover in the closed position, the seal being arranged to be broken when the safety cover is moved to the open position. The hub may therefore be provided as a sterile package that is automatically opened when the safety cover is flipped to the open position, without manual unwrapping being required. Alternatively, or additionally, the hub may optionally include a removable needle sheath. The needle sheath may be accommodated inside the safety cover (and any seal). -12-

Preferably the hub comprises means for locking the safety cover in the closed position. For example, the cover portion may include means for gripping onto the needle. A click-fit may be used to provide audible feedback when the safety cover is locked to the needle. This means that the needle stays covered even if an impulse were to be applied to the safety cover, so that it can not be accidentally knocked out of the closed position.

A particular advantage of a bi-stable safety cover is that is can be moulded as single plastics part. In a preferred set of embodiments the safety cover is integrally moulded with the hub.

There will now be described some general features that applicable to any of the embodiments described above.

In order to take advantage of the force amplification provided by a lever mechanism, it is preferable that the lever member(s) are relatively stiff. The lever member may comprise a front surface that is substantially transverse to the axis of the fluid transfer tip and one or more side surfaces that extend in a direction substantially parallel to the axis of the tip.

Each lever member may be pivotally mounted so that its side surfaces lift away from the prefilled fluid chamber when operated. However, in a preferred set of embodiments each lever member is pivotally mounted so that its side surfaces approach the fluid chamber when it is operated. This is because it is generally easier to push down on a lever member than to pull up a lever member.

Accordingly a user can operate the lever member by squeezing it against the fluid chamber. If the fluid chamber is flexible, for example squeezable pouch, then this may also help to transfer fluid out of the chamber. Single-handed operation may therefore be facilitated.

The lever member(s) may comprise a lever mechanism comprising multiple lever members, for example a linkage of pivoting lever members. A linkage mechanism may be designed to maximise the mechanical advantage while minimising the range of movement of the mechanism. A linkage mechanism may -13-therefore be ideally suited to small scale fluid transfer devices, where the fluid chamber has a relatively small volume e.g. 1 ml of fluid.

In some examples, the fluid transfer tip may comprise a male connector tip that is tapered to form a friction fit when inserted in a corresponding female hub. In some examples, the fluid transfer tip may comprise a tapered female part that forms a friction fit when a corresponding male part provided by the hub is inserted therein.

Alternatively, or in addition, the fluid transfer tip may comprise means for gripping a hub in a locked position. This may include a snap-fit connection, latch means, gripping finger, etc. that positively engage i.e. grip a hub when it is connected to the tip. This may be particularly suitable for high pressure fluid connections e.g. when transferring more viscous fluids.

The fluid transfer devices discussed herein may find a wide variety of uses, ranging from fluid transfer out of a vial into a syringe chamber, to infusion into an IV port, to extraction of blood from a vein or artery, to injections such as vaccinations, to cuff inflation and to connection of catheters for fluid extraction or administration.

Accordingly the fluid chamber may take the form of a syringe barrel, fluid delivery/extraction pipe or hose, etc.. The fluid chamber may be may be rigid (e.g. a syringe barrel) or flexible (e.g. a squeezable pouch). The fluid being transferred may comprise liquid and/or gas. The fluid may be a liquid, cream, gel, emulsion, etc. Some embodiments of the present invention will now be described, by way of example only, and with reference to the accompanying drawings, in which: Figures 1 a to 1 care perspective views of a first needle hub and fluid transfer device; Figures 2a to 2f demonstrate operation of the first fluid transfer device; Figure 3 is a perspective view of a second needle hub connected to a fluid transfer device; and Figures 4a to 4g demonstrate operation of the second fluid transfer device.

In Figures la to lcthere can be seen a first needle hub 2 having a safety cover 4 resiliently biased away from the needle 6, which is initially covered by a removable needle sheath 8. The needle hub 2 is connected to the fluid transfer tip of a syringe 12. A lever 14 is pivotally connected to the syringe 12 and arranged to operate on the needle hub 2 with its safety cover 4. The lever 14 is resiliently biased away from the syringe 12 and allows for single-handed operation. -14-

Operation of the syringe 12 and safety cover 4 will be understood with reference to Figures 2a to 2f. In Fig. 2a it is seen how the needle hub 2 is connected to the tip 10 of the syringe 12. As well as the friction fit of the tapered tip 10, the needle hub 2 is screwed into positive engagement with a threaded half collar 16 mounted on the front of the lever 14. As long as the lever 14 is in this initial position, resiliently biased away from the barrel of the syringe 12, then the needle hub 2 is locked by the engagement of the screw threads in addition to the friction fit, as is shown in Fig. 2b. When a user is ready to use the syringe 12 for a fluid transfer procedure, the needle sheath 8 is removed to expose the needle 6, as shown in Fig. 2c. The syringe 12 may then be used as per usual, e.g. pushing the plunger forwards to inject fluid and/or pulling the plunger back to withdraw fluid.

Once a procedure is complete, it is desirable for the needle 6 to be covered straightaway and without a user coming into contact with any potential contamination e.g. from fluid droplets carried by the needle. Fig. 2d shows how the lever 14 is operated by squeezing it towards the barrel of the syringe 12, against its resilient bias. Operation of the lever 14 pivots away its threaded half collar l6so that the needle hub 2 is no longer locked. As the threaded half collar 16 pivots back, it also pushes against the actuating portion of the safety cover 4 so as to move the safety cover 4 towards the needle 6. When the lever 14 is pressed down fully, as seen in Fig. 2e, the safety cover 4 is rotated to a closed position covering the needle 6. Releasing the lever 14 would allow the safety cover 4 to move back to an open position uncovering the needle 6, due to the resilient bias in the needle hub 2, except that the safety cover 4 grips onto the needle 6 in this closed position.

One or more barb-locks may be provided inside the U-shaped safety cover 4 to grip onto the needle 6. The needle 6 is then permanently covered and the needle hub 2 must be discarded. It is not possible to re-use the needle 6.

In addition to moving the safety cover 4, the lever 14 may also operate to loosen the friction fit of the needle hub 2. Thus in Figs. 2d and 2e the rotating front surface of the lever 14 may also be seen to push forwards against the needle hub 2. This facilitates separation of the needle hub 2 from the syringe 12 in a single-handed operation, e.g. without needing to unscrew or pull the hub 2. This can be helpful where the syringe 12 contains a sample to be processed rather than simply discarding the syringe 12 after an injection. In order to avoid the needle hub 2 being forcibly pushed away from the syringe 12 under the lever action, it can be seen that the lever 14 includes a catch member 18 that comes into engagement -15-with the hub 2 as the lever 14 is pressed down. It is only once the lever 14 is released to pivot back under its resilient bias, as shown in Fig. 2f, that the catch member 18 swings away from the loosened hub 2 and the hub 2 is then free to fall away fiom the syringe 12.

Although the needle hub 2 seen in this embodiment carries an outer screw thread, e.g. a Luer Lock type hub, a Luer Slip type hub may be used instead. Such a Luer Slip hub would connect to the tip 10 by a friction fit alone. Accordingly, the threaded collar 16 may optionally be omitted from the lever 14 in such embodiments.

In Figure 3 there can be seen a different kind of needle hub 102 connected to the fluid transfer tip of a syringe 112. In this example the needle hub 102 includes a bi-stable needle cover 104. As before, a lever 114 is pivotally connected to the syringe 112 and arranged to operate on the safety cover 104. The lever 114 is resiliently biased away from the syringe 112 and allows for single-handed operation.

Operation of the syringe 112 and safety cover 104 will be understood with reference to Figures 4a to 4g. In Fig. 4a it is seen how the needle hub 102 is connected to the tip of the syringe 112 e.g. with the friction fit of a standard Luer Slip connection. The needle hub 102 may be sealed by a plastic wrapper with its safety cover 104 in a closed position covering the needle 106. In order to move the safety cover 104 away from the needle 106 to an open position, the lever 114 is operated as shown in Fig. 4b. A first actuator 116 carried by the lever 114 pushes the bi-stable safety cover 104 so that it moves over-centre and flips to its open position, breaking open the plastic wrapper at the same time. A removable needle sheath (not shown) may optionally be provided underneath the safety cover 104. It is seen from Fig. 4c that the safety cover 104 is stable in the open position. The lever 114 may be released to return under its resilient bias, as seen in Figs. 4d and 4e. The close-up detail shows that a second actuator 118 carried by the lever 114 moves forward to a primed position below the safety cover 104, as the lever 114 moves back to its initial position. The syringe 112 may then be used to carry out a fluid transfer procedure.

When a user is ready to move the safety cover 104 back to its closed position and re-cover the needle 106, the lever 114 is simply operated again as seen in Fig. 4f. As the lever 114 pivots down, the second actuator 118 pushes back to apply an impulse to the bi-stable safety cover 104 that pushes it over-centre and -16-causes it to flip back to its closed position. As shown in Fig. 4g. the lever 114 may then be released to return under its spring bias while the safety cover 104 remains stable in the closed position. The lever 114 may be operated multiple times to open and re-close the safety cover 104. However, it is envisaged that in at least some examples the safety cover 104 may grip onto the needle 106 in the closed position of Fig. 4g so that the needle 106 is unusable and the needle hub 102 can be safely discarded.

Of course various embodiments of the present invention, such as those described above, are not limited to a fluid transfer device in the form of a syringe.

The lever may be pivotally connected to a device such as a blood collection tube, hose connection, catheter, etc. Furthermore the safety cover may not be associated with a separable needle hub but could be operated to cover and/or uncover any fluid transfer tip. -17-

Claims

Claims 1. A fluid transfer device comprising: a fluid chamber in communication with a fluid transfer tip; a safety cover moveable to cover the fluid transfer tip, wherein the safety cover is moveably connected to the fluid transfer tip and resiliently biased to a position uncovering the fluid transfer tip; and one or more lever members pivotally mounted to the fluid chamber, wherein the lever member(s) is/are operable to move the safety cover against the resilient bias so as to cover (or re-cover) the fluid transfer tip.
2. A fluid transfer device according to claim 1, wherein the safety cover is pivotally connected to the fluid transfer tip.
3. A fluid transfer device according to claim 1 or 2, wherein the lever member(s) is/are operable to move the safety cover so as to uncover the fluid two-way transfer tip.
4. A fluid transfer device according to any preceding claim, wherein the safety cover is pivotally connected to the fluid transfer tip and resiliently biased to an open position in which it is pivoted away from the tip.
5. A fluid transfer device according to claim 4, wherein the lever member(s) comprise a surface arranged to push against the safety cover to pivot it against the resilient bias into a closed position.
6. A fluid transfer device according to claim 4 or 5, wherein the safety cover is pivotally connected at a pivot point, the safety cover comprising a cover portion extending forwards of the pivot point and an actuating portion extending backwards of the pivot point to be acted upon by the lever member(s).
7. A fluid transfer device according to any preceding claim, wherein the lever member(s) is/are operable to move the safety cover from an open position to a closed position in which it covers (or re-covers) the fluid transfer tip, the device including means for locking the safety cover in its closed position. -18-
8. A fluid transfer device according to any preceding claim, wherein the fluid transfer tip includes a needle.
9. A fluid transfer device according to any of claims 1-7, wherein a needle hub is separably connected to the fluid transfer tip.
10. A fluid transfer device according to claim 9, wherein the lever member(s) also operate to loosen a friction fit of the needle hub.
11. A fluid transfer device according to claim 10, wherein the, or each, lever member comprises a front surface moveable between a first position proximal to the fluid chamber and a second position spaced from the first position towards a distal end of the fluid transfer tip so as to release the friction fit.
12. A fluid transfer device according to claim 11, further comprising a catch means arranged to catch the hub after it has been released from the friction fit by the front surface of the lever member moving towards the second position.Amendments to the claims have been filed as follows Claims 1. A fluid transfer device comprising: a fluid chamber in communication with a fluid transfer tip; a safety cover moveable to cover the fluid transfer tip, wherein the safety cover is moveably connected to the fluid transfer tip and resiliently biased to a position uncovering the fluid transfer tip; and one or more lever members pivotally mounted to the fluid chamber, wherein the lever member(s) is/are operable to move the safety cover against the resilient bias so as to cover (or re-cover) the fluid transfer tip.2. A fluid transfer device according to claim 1, wherein the safety cover is pivotally connected to the fluid transfer tip.3. A fluid transfer device according to claim 1 or 2, wherein the safety cover is 14') 15 pivotally connected to the fluid transfer tip and resiliently biased to an open position in which it is pivoted away from the tip. (00 4. A fluid transfer device according to claim 3, wherein the lever member(s) (\,J comprise a surface arranged to push against the safety cover to pivot it against the resilient bias into a closed position.5. A fluid transfer device according to claim 3 or 4, wherein the safety cover is pivotally connected at a pivot point, the safety cover comprising a cover portion extending forwards of the pivot point and an actuating portion extending backwards of the pivot point to be acted upon by the lever member(s).6. A fluid transfer device according to any preceding claim, wherein the lever member(s) is/are operable to move the safety cover from an open position to a closed position in which it covers (or re-covers) the fluid transfer tip, the device including means for locking the safety cover in its closed position.7. A fluid transfer device according to any preceding claim, wherein the fluid transfer tip includes a needle.8. A fluid transfer device according to any of claims 1-6, wherein a needle hub is separably connected to the fluid transfer tip.9. A fluid transfer device according to claim 8, wherein the lever member(s) also operate to loosen a friction fit of the needle hub.10. A fluid transfer device according to claim 9, wherein the, or each, lever member comprises a front surface moveable between a first position proximal to the fluid chamber and a second position spaced from the first position towards a distal end of the fluid transfer tip so as to release the friction fit.11. A fluid transfer device according to claim 10, further comprising a catch means arranged to catch the hub after it has been released from the friction fit by the front surface of the lever member moving towards the second position.IC) 15 12. A fluid transfer device substantially as hereinbefore described with reference (3 to Figures la-c and 2a-f. (Si r