Field of the invention

The present invention relates to a device for the safe removal of needles from syringes. In particular the device relates to the removal of a syringe needle from a syringe barrel of a disposable syringe. The present invention also extends to a method of the safe removal of a needle from a syringe barrel.

Background to the invention

Syringes, in particular disposable syringes are an important device within many business sectors, including in scientific research laboratories for the transfer of fluids, and in particular, in the healthcare sector for administering drugs and for taking fluid samples from a patient. Typically, a syringe is formed of a three-component system comprising: a syringe barrel with a plunger; and a needle. Syringes can be provided ready assembled, or more typically, the syringe and the needle are provided separately to be assembled by the end-user.

Accidental injuries caused by needles are acknowledged to be a substantial risk.

If the needle has a sharp end then this itself poses a physical risk of injury, furthermore, once the needle has been used it may be contaminated by biological matter or chemicals presenting its own risk or increasing the risk further.

The term used for an injury caused by a needle is often termed a sharps injury, or a needle-stick injury. Those who suffer a needle-stick injury may be exposed to disease or chemical contamination. The very nature of a needle stick injury means the contaminant is passed through the body’s natural defence of the skin directly into tissue or the blood stream. In the worst cases, the result of a needle stick injury can be life changing, either through the effects of chemical poisoning or contracting a blood borne disease, such as hepatitis B, hepatitis C and HIV.

In light of the above risks and adverse outcomes of needle-stick injuries, the costs associated with insurance claims and compensation for accidents involving needles places a burden on healthcare systems and professionals. As an example, between 2012 and 2017, the NHS in the UK received 1 ,833 incident claims for needle-stick injuries; of these 1 ,213 were successful leading to payments of over £4 million in compensation (“Did you know? Preventing needlestick injuries, NHS Resolution, May 2017).

According to a report by the European Parliament (“Preventing needle-stick injuries in the health sector”, 11th February 2010), in the EU more than one million needle-stick injuries occur every year. Taking Spain as an example, between 1996 and 2000, 87% of the recorded sharps injuries were due to needles (Cullen BL et al. J Hosp Infect 2006; 63:445-51). In the United States, there are an estimated 385,000 needle-stick injuries every year with 96% occurring either during use, after use/before disposal, or during and after disposal according to the United States Department of Health and Human Services Centers for Disease Control and Prevention (Workbook for Designing, Implementing and Evaluating a Sharps Injury Prevention Program; April 2008).

Several methods to mitigate the risks of injury resulting from needles during disposal of needles are known. In many cases, needles are disposed of in single use puncture-proof sharps containers. These containers typically have some form of crude needle removal device in the form of a slot or groove on the edge of the opening to the container which is used to grip and separate by force the needle from the syringe. The containers are typically provided as a complete assembly which is then sealed once an indicated maximum level is reached. While popular, this can be an ineffective solution as most sharps bins are not fixed to a surface and therefore the forces required to remove the needle means the user must place a second hand on the bin to steady it while the needle is detached. This undesirably brings a user’s hand towards the exposed needle. Furthermore, with a wide open mouth to the container, and in view of the fact that the cost of disposal of sharps bins is relatively high, there is a propensity to overfill the bins often resulting in needles protruding from the open mouth of the container during use and sometimes having to agitate the full bin to cause the needles to drop below the sealing lid prior to closure. Neither of these practices is safe.

Other forms of “safety engineered devices” or SEDs are also known, for example the AutoShield Duo ^® safety pen needles from Becton Dickinson ^® which while effective for certain uses are relatively expensive. Equally, the use of needle clippers that remove the tip of the needle for transfer to a sharps bin, or tools to remove the needle are available but this requires additional equipment, often additional training and yet still requires the use of two hands, and at least one of those hands to be brought close to the exposed end of the needle.

Regulations and safety standards are evolving and guidance is increasing focussed on disposal of the needle and syringe in a safer manner, preferably with a single-handed operation.

GB 2544472B describes a needle removal device that allows for safe, typically, single-handed removal of a needle from a syringe, enabling safe disposal of used needles to a suitable receptacle, and thereby reducing the risk of injury. This device represents a significant improvement to the needle removal devices available at the time.

The device in GB 2544472B makes use of two, spatially-separated, layers of closure members having an aligned opening through the centre of the members. In its simplest form, for push-on type needles the needle passes through the opening causing the tips of the planar members to flex to allow the needle to pass and then close to surround the tip of the syringe behind the needle. The syringe is then retracted by the operator resulting in a biasing force of the closure members to the needle causing it to separate from the syringe. While generally effective, the device requires the operator to ensure that the needle has passed into the device sufficiently such that the needle passes both layers of closure members. Due to the separation of the closure members, if positioned incorrectly, removal of the needle may not be achieved due to only one set of springs actuating on the needle which may not offer enough force to remove it and the removal process must be repeated or the needle may become stuck between the two layers of springs.

Furthermore, due to the separation of the closure members, the two layers of springs are unfavourably far apart at the aligned opening which means the springs may not fit as easily or as effectively between the top surface of the needle and the bottom surface of the syringe which may impede effective needle removal.

GB 2544472B describes an alternative method for removal of screw-on type needles where the needle is pushed into the opening such that the needle is gripped in the opening retarding rotation when the syringe body is rotated by the user. Once the needle and the syringe are separated then then the needle is pushed into the container and the syringe retracted. Again, this is generally effective, but the force required to retard rotation of the needle, in view of the separation of the layers of the closure members and the fact that only one spring may be offering the retarding force, requires thicker materials which in turn increases the force required to insert the needle. In addition, the rounded shape of the ends of the closure members and the overall rounded shape of the aligned opening in contact with the needle provide no or little physical barrier to rotation.

It therefore remains desirable to provide device and methods that offer a more effective and more reliable needle removal performance.

It would also be desirable to reduce the force required to insert and remove the needle, instead directing load forces to act on each of the closure members to increase the reliability of the method and creating specifically optimised features that further improve the operation of the device. It would also be desirable to ensure the needle is contained below the needle removal device and within a container resulting in a reduced risk splashing of contaminants.

The present invention addresses one or more of the aforementioned problems to facilitate the safe, effective, reliable and reproducible removal of a needle, preferably in a single-handed operation. As a result, the invention provides safety benefits and reduced costs for sharps disposal.

Summary of the Invention

In a first aspect, the present invention provides a device to separate a needle from a syringe, the device comprising: - a first spring layer comprising one or more first spring members;

- a second spring layer comprising one or more second spring members; wherein the first spring layer and the second spring layer are arranged in a stacked, overlying orientation to provide a spring layer stack, the spring layer stack arranged to cover an aperture in a surface; wherein the or each first spring member is attached at an edge of the aperture and extends radially inwardly to an edge adjacent a first opening positioned at or towards the centre of the aperture, and the or each second spring member is attached to an edge of the aperture and extends radially inwardly to an edge adjacent a second opening positioned at or towards the centre of the aperture; wherein the first opening is aligned with the second opening to provide an aligned opening through the first and second spring layers; wherein the or each first spring member and the or each second spring member is formed of a resiliently deformable material wherein the first and second spring layers are biased to an at-rest first position from which, in use, they are able to deflect to a second position to accept a needle that is attached to a syringe when it is pushed into the aligned opening by a user; wherein the first spring layer and the second spring layer when in the at-rest first position are in contacting relation at the aligned opening.

As defined herein, “contacting relation” in this context is intended to refer to the first spring layer and the second spring layer being in contact, or sufficiently closely spaced to act as if in, or to have the benefits of being in. contact. Suitably, the spacing or gap between the first spring layer and the second spring layer at least at, or in the proximity of, the aligned opening may be at most 1 mm, suitably at most 0.7mm, suitably at most 0.5mm, suitably at most 0.3mm, suitably at most 0.1 mm, suitably at most 0.05mm, suitably at most 0.03mm, suitably at most 0.01 mm. The first spring layer and the second spring layer may be “contacting” meaning that they are touching, i.e. have no gap or space between at least at, or in the proximity of, the aligned opening.

In embodiments, the first spring layer is in full contacting relation with the second spring layer. The term “full contacting relation” in this context means that substantially all, or all, of the first spring layer is in contact with the second spring layer or substantially all, or all, of the second spring layer is in contact with the first spring layer. Suitably, substantially all, or all, of the first spring layer is in contact with substantially all, or all, of the second spring layer.

In embodiments, the first spring members of the first spring layer and the second spring members of the second spring layer are substantially, or exactly, parallel. In other words, the radially inward projection of the or each first spring member to or towards the centre of the aperture over which they extend has the same or substantially the same angle as the radially inward projection of the or each second spring members; in this context, the angle being measured, for example, with respect to flat as herein defined. In embodiments, the first spring layer and the second spring layer exert a biasing force against each other. Suitably, the biasing force is between 0 Newtons and about 20 Newtons.

In embodiments, when in the at-rest first position the first spring layer and/or the second spring layer are substantially flat as herein defined. Alternatively, in embodiments, when in the at-rest first position the first spring layer and/or the second spring layer are angled from the edge of the aperture to the aligned opening by about 5° to about 30° from flat as herein defined. Alternatively, or in addition, when in the at-rest first position the first spring layer and/or the second spring layer are angled in a region around the aligned opening by about 10° to about 30° from flat as herein defined. Suitably, when the first spring layer and second spring layer are angled, or partially angled, the angle of deflection is away from the intended direction of entry of a needle to be removed from a syringe.

In embodiments, the region around the aligned opening has a diameter of between about 5mm and about 30mm.

In embodiments, the first spring layer comprises four first spring members and/or the second spring layer comprises four second spring members.

In other embodiments, a free edge of each first spring member from the edge of the aperture to the first opening is in closely-spaced contiguous alignment with a free edge of at least one other first spring member; and/or a free edge of each second spring member from the edge of the aperture to the second opening is in closely-spaced contiguous alignment with a free edge of at least one other second spring member. Suitably, the free edges of the first spring members are rotational offset around a longitudinal axis through the centre of the aperture from the free edges of the second spring members.

In embodiments, the aligned opening has a shape matching that of a cross section of a needle to be removed from a syringe. Suitably, the shape is chosen to retard rotation of a needle, suitably a shank of a needle, having the same cross-sectional shape is inserted into the aligned opening. Suitably, the shape of the aligned opening derives predominantly, or is due to the shape of the opening in the first spring layer, or the shape of the opening in the second spring layer, or both. Suitably, the shape of the aligned opening is generally square.

In embodiments, the surface comprising the aperture is part or all of one side of a receptacle for containment of needles. Suitably, the first spring layer and the second spring layer, when angled in accordance with embodiments of the invention, are angled inwardly from flat into the interior of the receptacle.

In embodiments, the device is surrounded by an upstanding wall on at least one side for restricting access of a user’s fingers to the device.

In a second aspect, the invention provides a container for retaining waste needles comprising the device according to the first aspect of the invention.

In a third aspect, the invention provides a method of removing a push-fit needle from a syringe, the method comprising the steps of: a) Providing a device of the first aspect of the invention; b) Providing a syringe attached to a needle by a push-fit attachment c) Inserting the needle into the aligned opening so that the needle and a portion of the syringe to which the needle is attached has passed the aligned opening and the first and second closure members have returned toward or to the at-rest first position; d) Retracting the syringe wherein the first and second spring layers act to apply a biasing force to the needle as the syringe is retracted to thereby remove the needle from the syringe.

In a fourth aspect, the invention provides a method of removing a screw-fit needle from a syringe, the method comprising the steps of: a) Providing a device of the first aspect of the invention; b) Providing a syringe attached to a needle by a screw-fit attachment; c) Inserting the needle into the aligned opening so that the needle such that the needle is gripped by the aligned opening; d) Rotating the syringe relative to the needle such that the needle is separated from the syringe; e) Pushing the needle through the aligned opening with the syringe; f) Retracting the syringe.

In a fifth aspect, the invention provides a method of removing a bayonet-fit needle from a syringe, the method comprising the steps of: a) Providing a device of the first aspect of the invention; b) Providing a syringe attached to a needle by a bayonet-fit attachment; c) Inserting the needle into the aligned opening so that the needle such that the needle is gripped by the aligned opening; d) Pushing and then rotating the syringe relative to the needle such that the needle is separated from the syringe; e) Pushing the needle through the aligned opening with the syringe; f) Retracting the syringe.

Brief description of the Drawings

Figure 1 shows top perspective views of the embodiment of the device according to the present invention. Figure 1a shows an embodiment where the ends of the spring members adjacent to the opening in the top and bottom layer are shaped to provide a generally octagonal hole in the aligned opening; Figure 1 b shows an alternative embodiment where the ends of the spring members adjacent to the opening in the bottom layer only are shaped to provide a generally square hole in the aligned opening.

Figure 2 shows a cross-sectional view of the embodiment of the device according to the present invention shown in Figure 1a: (a) a variant with an over-biased design at the junction of the spring members to the aperture edge 13a; (b) an alternative variant that does not have an over-biased design with a substantially flat junction with the surface in which it is placed.

Figure 3 shows multiple embodiments of a device according to the present invention, whereby the spring layers are either in contact with each other or very closely spaced to each other. Figures 3.1 to 3.9 show embodiments of the device in accordance with the present invention each having varying numbers and arrangements of spring members. The embodiments shown in Figures 3.2, 3.3 and 3.5 to 3.9 have a central angled tip portion of each spring member in accordance with an embodiment of the present invention. Figure 3.1 shows a triple-pair springs design; Figure 3.2 shows a triple-pair springs with triangular form, downward facing, steeper angled spring tips; Figure 3.3 shows four-pair spring with circular conical form, downward facing, steeper angled spring tips and square aligned opening; Figure 3.4 shows a four-pair springs design; Figure 3.5 shows a four-pair springs with square pyramidal form, downward facing, steeper angled spring tips; Figure 3.6 shows a four-pair springs with circular conical form, downward facing, steeper angled spring tips; Figure 3.7 shows a six-pair springs with hexagonal form, downward facing, steeper angled spring tips; Figure 3.8 shows a four-pair springs with circular conical form, downward facing, eight steeper angled spring tips; Figure 3.9 shows a four- pair springs with octagonal form, downward facing, eight steeper angled spring tips.

Figure 4 shows a more detailed view of the embodiment of the device according to the invention shown in Figure 3.6. The upper figure shows a top view of the device with a central angled section having a diameter of approximately 12mm. The bottom figure shows the same device superimposed with the lower second spring layer wherein the spring members are offset by 45° around a longitudinal axis through the opening in the centre perpendicular to the page.

Figure 5 shows a cutaway top perspective view of the embodiment of the device according to the present invention having a central angled tip portion of each spring member.

Figure 6 shows a cross-sectional view of the embodiment of the device according to the present invention shown in Figure 5.

Figure 7 shows an enlarged view of the embodiment of the device of the present invention shown in Figures 5 and 6. There is no gap between the spring layers. There is a force acting between the upper and lower members which maintains the contacting relation between the two spring members.

Figures 8a to 8d show a series of chronological images showing the method of removing a needle from a syringe in accordance with an embodiment of the invention. Figure 8a shows the needle attached to a syringe being advanced toward an embodiment of the device of the present invention; Figure 8b shows the needle partially inserted into the device, the needle being engaged with the spring members; Figure 8c shows the needle passing the spring members, and the spring members returning toward their at-rest position to grip the syringe connector behind the needle; and Figure 8d shows the needle being separated from the syringe.

Figure 9 shows three embodiments of a device according to the present invention, whereby the spring layers are either in contact with each other or very closely spaced to each other. Figure 9.1 : shows an embodiment with a flat spring layer design. The forces required for insertion of a needle attached to a syringe, and retraction with removal of the needle are normalised to this embodiment at 100% for each; Figure 9.2: shows an embodiment with an angled spring layer design, wherein the angle of the spring members is 5° from the aperture edge to the opening at the centre of the aperture. The force on the needle on entry is an estimated 90%, and the estimated force on the needle on exit is 110%; Figure 9.3: shows an embodiment with an angled spring layer, or “mini-hex conical” design, wherein the angle of the spring members forming a cone-shaped depression in the centre of the spring layer is 20°. The force on the needle on entry is an estimated 60-70%, and the estimated force on the needle on exit is 130-140%. Figure 9.4: shows a ‘hybrid’ embodiment with the first or top spring layer has a “mini-hex conical” design, wherein the angle of the spring members forming a cone-shaped depression in the centre of the spring layer is 20°, and the second or bottom spring layer has an angled spring layer design, wherein the angle of the spring members is 5° from the aperture edge to the opening at the centre of the aperture. The force on the needle on entry is an estimated 70-80%, and the estimated force on the needle on exit is 120-130%;

Figure 10 shows a cross-sectional view of the prior art device of GB 2544472B for comparison. The first and second closure members are not parallel and there is a significant gap of approximately 2mm between them at their closest point.

Detailed Description

Prior to setting forth the invention, a number of definitions are provided that will assist in the understanding of the invention. All references cited herein are incorporated by reference in their entirety. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Unless otherwise indicated by context, the use herein of the singular is to be read to include the plural and vice versa. As such the terms “a”, “an”, “one or more”, and “at least one” are used interchangeably herein.

As used herein, the term “comprising” means any of the recited elements are necessarily included and other elements may optionally be included as well. “Consisting essentially of means any recited elements are necessarily included, elements which would materially affect the basic and novel characteristics of the listed elements are excluded, and other elements may optionally be included. “Consisting of means that all elements other than those listed are excluded. Embodiments defined by each of these terms are within the scope of this invention.

As used herein the term “contacting relation” is intended to refer to two or more articles being in contact or sufficiently closely spaced to act as if in contacting relation. The term “contacting” or “contact” refers to articles that are touching, i.e. have no gap or space between.

The term “inward” or “inwardly” as used herein refers to a direction towards or into the interior volume of a receptacle for receiving, storage and/or disposal of needles. Conversely, the term “outward” or “outwardly” as used herein refers to a direction towards or out of the interior volume of the receptacle.

The term “radially inward” or “radially inwardly” refers to a direction to or toward a defined object or centre thereof (or an approximation thereto).

As used herein the terms “resiliently deformable” and “flexible” refer to the ability of a material or a structure to bend or flex under a suitable force and when that force is removed to return substantially or exactly to the original shape or position.

The term “syringe” is intended to refer to any suitable variable volume receptacle for liquids from which a needle attached thereto can be removed. Suitably, a syringe refers to a device having tubular body with a nozzle and piston for sucking in and ejecting liquid through the nozzle via a reciprocating movement of the piston in the tubular body. The term may refer equally to syringes made of any material, including glass and plastic, and may refer to reusable or single-use disposable syringes. Suitably, syringe can be attached to a needle in use in a removable manner, for example using a push- on, bayonet or screw-on attachment.

The term “needle” as used herein refers to a needle as used in common parlance. Suitably, a needle is elongate with a rod-like shape. The needle may be solid or suitably have a central lumen extending therethrough from one end to the other that allows passage of fluid, e.g. liquid or gas, as for example found in hypodermic needles used in medicine. Suitably the needle may have a rounded or blunt end, suitably, a needle has a sharpened end to promote piercing of an object into which it is inserted. Suitably, the needle can be attached to a syringe in use in a removable manner, for example using a push-on, bayonet or screw-on attachment.

As used herein the term “push-fit” with reference to a needle implies a needle that is removably attached to a syringe by a linear sliding motion of the needle onto a tip of the syringe. As used herein the term “screw-fit” with reference to a needle implies a needle that is removably attached to a syringe by a rotational movement onto a helical thread on a tip of the syringe. As used herein the term “bayonet-fit” with reference to a needle implies a needle that is removably attached to a syringe by a linear sliding motion followed by a rotational movement to lock the needle to a tip of the syringe.

The present invention provides a syringe needle removal device.

Typically, syringes, such as hypodermic syringes used in medicine and science, comprise a syringe body that includes a syringe barrel or body and a plunger or piston slidably located therein, and a needle. The needle is often attached to the syringe body at a narrowed syringe tip, located at an end away from the actuator end of the plunger. The needle may be adapted for attachment to the syringe by having a needle connector attached at one end of the needle lumen or shaft. The needle may be removable after use to allow for separate disposal streams for each component.

The attachment of the syringe body to the needle is typically non-permanent; suitably the attachment is via a push-fit (for example the standardized Luer-slip friction fitting system), bayonet or screw-thread type fitment. Removal of the needle is typically effected by a user gripping each of the syringe body and the needle with their hands and applying the required force and/or movement for separation. This action however brings the user's fingers close to the needle itself and so increases the risk of accidental injury.

The present invention has an advantage of allowing removal of the needle by gripping the syringe body only thereby minimizing this risk by enabling a user to carry out separation without the user's hand having to come near to the needle.

Referring initially to Figures 1a and 2, an embodiment of the needle removal device of the present invention is shown. The device 10 is shown as part of a surface or container 11 (only part of which is shown).

The container 11 comprises an aperture 13 (not shown) having a rim, or an edge 13a. In embodiments, the aperture 13 may be of any suitable size. Suitably, the aperture 13 may have a diameter of between 1 cm and 10cm, or 2cm to 5cm. Suitably, the aperture 13 may have a minimum diameter of 1 cm, 2cm, 3cm, 4cm, 5cm, 6cm, 7cm, 8cm or more. Suitably, the aperture may have a maximum diameter of 10cm, 9cm, 8cm, 7cm, 6cm, 5cm, 4cm, 3cm or less. The diameter taken as the maximum distance between two points on the edge of the edge 13a of the aperture 13 whether the aperture 13 is circular or otherwise.

In embodiments, the aperture edge 13a may be an aperture wall 14 as shown, or may simply be the area surrounding the aperture 13 in the container 11 into which the device is positioned. The aperture edge 13a may be considered to be the limit of the surface surrounding the aperture, or it may extend at least partially over the surface. The aperture edge 13a may alternatively be considered to extend to the region surrounding the aperture 13.

The device 10 comprises a first spring layer 15. As used herein, the term “spring layer” refers to a resiliently deformable gripping or retaining feature of the device that flexes or deflects to receive a needle attached to a syringe for removal before returning to or toward an at-rest position for capturing and removal of the needle from the syringe. The spring layers may be generally planar extending to cover an aperture and thereby substantially close that aperture. The term “planar” in this context refers to the feature being a layer, i.e. having a width and breadth in excess of its thickness; the term “planar” in this context also includes a layer that has a portion that is angled, or is in its entirety angled, as defined herein. Suitably, the angle is inwardly into a container in which the removed needles are retained. The spring layer may comprise one or more spring members.

The first spring layer comprises one or more first spring members 16. As used herein “spring member” refers to the one or more segments, sections, or pieces, or components, of the spring layer that act to cover or close an aperture in the surface in which the device is mounted. In embodiments, the spring layer may comprise 2 or 3 spring members; suitably, the spring layer comprises 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16 or more spring members.

In the embodiment shown in Figures 1a and 2, the first spring layer 15 consists of four first spring members 16, each first spring member 16 may be suitably formed of a resiliently deformable material so each first spring member 16 may deflect or flex away from the at rest position shown when acted on by a force before returning to the at rest position when the force is removed. Suitable resilient materials include, but are not limited to, polyethylenes, polypropylenes and polyterephthalates such as Nylons (RTM).

In the embodiment shown, each first spring member 16 is attached at a radially outer edge to the aperture edge 13a and extends radially inwardly towards a central area, i.e. an area away from the aperture edge 13a, Suitably the central area is the geometric or approximate geometric centre, of the aperture 13. The free edges of each first spring member 18, 19 extending from the aperture edge 13a may be in close spaced relationship, and preferably contiguous with a free edge of at least one other neighbouring first spring member 16. The separation of the first spring members 16 along the free edges facilitates the flexing of the first spring member 16 in use.

While a spring layer 15 having only one spring member 16 is contemplated, two, three or more is preferred to alter, suitably reduce, the force required to deflect each spring member. Suitably, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen or more first spring member 16 may be present in the first spring layer 15. A first spring member 16 needs to retain sufficient resilience, either through the material of which it is made, the shape, the number, of the design of the first spring layer 15 or a combination of all of these to apply sufficient force to grip and/or to enable separation of the needle from the syringe as described below.

Each first spring member 16 is adapted, arranged and/or shaped such that the first spring layer 15 has a hole, or gap, or opening 13b therein. Suitably, the opening 13b is in the central area (i.e. away from the edge, or in the centre) of the aperture 13. The opening 13b may be formed by shaping a tip of each first spring member 16, for example, by rounding, such that edge of the opposing first spring members 16 is sufficiently separated to provide the opening 13b. Alternatively, each first spring member 16 may be dimensioned, for example, shortened, to achieve the same result. The opening 13b may be any suitable shape. The shape of the opening 13b may be geometric or non-geometric. The shape of the opening 13b may be regular or irregular. Suitably, the shape of the opening is defined by the shape of the end of the first spring members 16 adjacent the opening 13b. Suitably, the opening 13b may have a shape when viewed in plan, or from above, that is generally circular, elliptical, or polygonal (regular or irregular), square or diamond (inverted pyramidal form), a hexagon (an inverted hexagonal cone), an octagon (an inverted octagonal cone) or a triangle (an inverted tetrahedral form).

The opening 13b may be any suitable size. In embodiments, the opening may be sized to receive a needle and have a diameter between that of the diameter of the syringe tip from which the needle is to be removed and the diameter of the needle or needle connector or hub that is forms an attachment with the syringe. Suitably, the opening 13b may have a diameter of between 1 mm and 10mm, or 2mm to 5mm. Suitably, the opening 13b may have a diameter of at least 1 mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm or more. Suitably, the opening 13b may have a diameter of at most 20mm, 19mm, 18mm, 17mm, 16mm, 15mm, 14mm, 13mm, 12mm, 11 mm, 10mm or less. The diameter taken as the maximum distance between two points on the edge of the opening whetherthe opening is circular or otherwise.

As described later, the opening 13b receives the needle which is to be removed initially attached to a syringe.

As best shown in Figure 2, the device 10 further comprises a second spring layer 15’. The second spring layer 15’ is similar in nature to the first spring layer 15 and differs only by way of the features that are explicitly described below. Corresponding features in the second spring member 15’ are numbered as for the first spring member 15 with the addition of a prime character after the number.

The second spring layer 15’ is positioned in a stacked, overlying relation beneath the first spring layer 15. In other words, the first and second spring layers lay on top of each other. In the embodiment shown in Figures 1a and 2, for example, the first spring layer 15 is formed as a separate component to the second spring layer 15’ and the overlaying relation is established only after assembly of the device. Alternately, the first and second spring layers are formed as a unitary piece (not shown).

Second spring members 16’ of the second spring layer 15’ may, as shown, be aligned or they may suitably be rotationally offset relative to the spring members 16 around a longitudinal axis passing through the aperture 13. The degree of rotational offset may be chosen to adjust the degree of deflection of the spring layers of the device 10. Suitably, the offset may be chosen such that the edges 18, 19 of two spring members in one spring layer may lie substantially, or directly, below the centre of a spring member in the other spring layer. For example, for spring layers each comprising four spring members, the degree of offset may be 45°.

The second spring layer 15’ has an opening 13b’ in the central area of the aperture 13. Suitably the aperture 13b’ is aligned with the opening 13b in the first spring layer 15 to provide an aligned opening 13b/13b’. The aligned opening has dimensions, in particular a diameter, that are the same or approximately the same as each opening 13b and 13b’. The aligned opening formed by openings 13b and 13b’ are sized to allow a needle to be pushed through the device 10, into the interior volume of the container 11 .

The opening 13b’ may be any suitable shape. The shape of the opening 13b’ may be geometric or nongeometric. The shape of the opening 13b’ may be regular or irregular. Suitably, the shape of the opening is defined by the shape of the end of the second spring members 16’ adjacent the opening 13b’. Suitably, the opening 13b’ may have a shape when viewed in plan, or from above, that is generally circular, elliptical, or polygonal (regular or irregular), square or diamond (inverted pyramidal form), a hexagon (an inverted hexagonal cone), an octagon (an inverted octagonal cone) or a triangle (an inverted tetrahedral form).

The shape of the aligned opening will be a defined by the combination and orientation of the opening 13b and 13b’. Suitably, the aligned opening 13b, 13b’ may have a shape when viewed in plan, or from above, that is generally circular, elliptical, or polygonal (regular or irregular), square or diamond (inverted pyramidal form), a hexagon (an inverted hexagonal cone), an octagon (an inverted octagonal cone) or a triangle (an inverted tetrahedral form).

As best shown in Figure 1 b, in embodiments, suitably those embodiments where the needle to be removed is attached to the syringe by a bayonet or screw-type fitting, the aligned opening 13b/13b’ has a shape and size that matches a cross-sectional shape of a needle such then when the needle is inserted in and engaged with the aligned opening 13b, 13b’ the needle is suitably gripped such that rotation of the needle Is retarded when the syringe is rotated, or pushed and rotated, as appropriate. For example, the shape of the aligned opening 13b, 13b’ when viewed in plan may be substantially square to interact with flat edges on four sides of the needle, as shown in Figure 9b.

In embodiments, the shape of the aligned opening 13b, 13b’ is created by the shape of the tip of one or more of the spring members 16, 16’. When each of the spring members 16, 16’ has rounded tips then the aligned opening 13b/13b’ has a shaped when viewed in plan of a circle and provided little or no rotational restriction on the needle when rotated in the aligned opening 13b, 13b’. If one or more of the spring members 16, 16’ has a squared off tip then this may be used to impart rotational restriction on the needle. Each of the spring members 16, 16’ may have tips shaped to prevent rotation of the needle, or only some of the spring members 16, 16’ may have such shapes. Suitably, either the or each of the first spring members 16 have shaped tips to prevent rotation of a needle, and/or the or each of the second spring members 16’ have shaped tips to prevent rotation of a needle.

It is to be understood that the number of second spring members 16’ in the second spring layer 15’ can be the same or different to that of the number of first spring members 16. However, for simplicity of manufacturing a first spring layer 15 and a second spring layer 15’ having the same number of spring members 16, 16’ may be convenient. The first spring layer 15 and/or the second spring layer 15’ may be arranged to be flat (for example, the embodiment shown in Figure 9.1) with respect to the rim 13a of the aperture 13. Suitably, the first spring layer 15 and/or the second spring layer 15’ are both arranged to be flat. The term “flat” in this context meaning the first and/or second spring members 16, 16’ of the first and/or second spring layers 15, 15’ do not project substantially outwardly from interior of the container in which the device is, or could be, fixed, or project substantially inwardly into the interior of that container. In embodiments where the device is positioned in a container having a top surface that is parallel to the floor, this would mean the spring layers are horizontal. The term “flat” can also mean the first and/or second spring members 16, 16’ are within, and at least substantially parallel with, the plane of the surface in which the device is positioned.

In alternative embodiments (for example, the embodiments shown in Figures 1a, 2 and 9.2), at least a portion of the first spring layer 15 and/or the second spring layer 15’ may be arranged to project inwardly, or downwardly, into the interior of the container in which the device is, or could be, fixed. Suitably, at least a portion of the first spring layer 15 and the second spring layer 15’ are arranged to project inwardly, or downwardly, into the interior of the container in which the device is, or could be, fixed. Alternatively, the first and/or second spring members 16, 16’ may be arranged to project inwardly, or downwardly, from the plane of the surface in which the device is positioned. In embodiments, one or more, or each of the entire spring members 16, 16’ projects from their fixed edge at the rim of the aperture 13 inwardly, or downwardly, towards the central area of the aperture 13. Suitably, the spring members 16, 16’ project from their fixed edge at the rim of the aperture 13 inwardly, or downwardly, to a most inward, or downward point at the opening 13b, 13b’.

In alternative embodiments (for example the embodiment shown in Figure 1 b, 9.3 and Figures 5 and 6), or in addition to the embodiments above, a portion of one or more, or each of the spring members 16, 16’ may be flat or project inwardly or project outwardly at an angle greater than, or less than, or otherwise at a different angle to the remainder of the or each spring member 16, 16’. This embodiment may be identified as the “angled spring tip design”. In these embodiments, the remainder of the or each spring member, or portion thereof, may be flat, or projecting inwardly, or projecting outwardly. Suitably, the portion of each spring member 16, 16’ that is flat or projects inwardly or projects outwardly more than the remainder of the or each spring member 16, 16’ is located in an area in or towards a central area of the aperture 13. Suitably, a portion of each spring member 16, 16’ nearest the central area of the aperture 13 is angled, suitably projecting inwardly or downwardly such that a depression or hollow 20 is formed in the first and second spring layers 15, 15’; or suitably projecting outwardly or upwardly such that a protrusion or raised generally conical section is formed in the first and second spring layers 15, 15’. Suitably the hollow 20 or the conical section is located over the central area, suitably over the centre or over the central area or otherwise away from the edge of the aperture. Suitably, the hollow 20 or the conical section may have a shape when viewed in plan, or from above, that is generally circular (an inverted conical or frustoconical form), elliptical, or polygonal (regular or irregular) square or diamond (inverted pyramidal form), a hexagon (an inverted hexagonal cone), an octagon (an inverted octagonal cone) or a triangle (an inverted tetrahedral form). In a specific embodiment where each of the first and second spring layers 15, 15’ comprise four spring members 16, 16’, the shape of the hollow 20 or the conical section may be a square or a regular octagon. In embodiments, at the centre of the hollow 20 or the conical section is the opening 13b, 13b’.

The angle of one spring layer (or part thereof) and another spring layer 15’ (or part thereof) may be the same or it may be different. The embodiment shown in Figure 9.4 employs a ‘hybrid’ design where the first or top spring layer 15 is generally flat as defined herein with an angled tip design, whereas the second or lower spring layer has a generally angled design such that the spring layers meet at the aperture edge 13a and at the aperture 13b/13b’. This may be particularly beneficial as it provides a cone or hollow 20 that provides a clear target for the user inserting the needle/syringe, and yet provides the additional rigidity of the planar lower spring layer for additional grip on the needle. This feature also ensures maximum contact and compression of the two spring layers in the area surrounding the aligned opening 13b, 13b’, and minimises the height of the two layers at this point which ensures the springs will fit between the top surface of the needle shank and the bottom surface of the syringe to give maximum force effect for the needle removal action.

Suitably, the hollow 20 or the conical section may have a diameter (or breadth or width) of between 5mm and 30mm, or 10mm to 15mm. Suitably, the hollow 20 may have a diameter of at least 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11 mm, 12mm, 13mm, 14mm, 15mm or more. Suitably, the hollow 20 may have a diameter of at most 20mm, 19mm, 18mm, 17mm, 16mm, 15mm, 14mm, 13mm, 12mm, 11 mm, 10mm or less. The diameter taken as the maximum distance between two points on the edge of the hollow 20 whether the opening 20 is circular or otherwise.

As best shown in Figures 3.10, 3.11 and Figure 4, in embodiments, the free tip or end of the or each spring member 16, 16’ may have a cut or incision or join or fold 17 to allow flexing of one spring layer 15 or 15’ with the offset other spring layer 15’ or 15. The incision may be of any length. Suitably the incision is dimensioned so that it begins at the tip of the spring member 16, 16’ and ends at an outer edge of the hollow 20. In embodiments, the incision may overlie the edge 19 of a spring member in the spring layer below.

In embodiments, the angle of projection of the first spring layer 15 and/or the second spring layer 15’, or part thereof, suitably into or out of the interior of the container in which the device is, or could be, fixed, may be between 0° and 50°. Suitably, the angle of projection may be between 0° and 20°. Suitably, the angle of projection may be between 5° and 15°. Suitably the angle of projection may be at least 0°, 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, 9°, 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 19°, 18°, 17°, 16°, 15°, 14°, 13°, 12°, 11°, 10° or more. Suitably, the angle of projection may be at most 50°, 49°, 48°, 47°, 46°, 45°, 44°, 43°, 42°, 41°, 40°, 39°, 38°, 37°, 36°, 35°, 34°, 33°, 32°, 31°, 30°, 29°, 28°, 27°, 26°, 25°, 24°, 23°, 22°, 21°, 20°, 19°, 18°, 17°, 16°, 15°, 14°, 13°, 12°, 11°, 10°, 9°, 8°, 7°, 6°, or 5° or less. All angles being defined from flat as previously defined. In embodiments, the angle or projection of the first spring members 16 and the second spring members 16’ are optimised so that they are in at least partial contacting relation. Suitably, the first spring members 16 and the second spring members 16’ touch or are very close at least the aligned openings 13b and 13b’. Suitably, the angle or projection of the first spring members 16 and the second spring members 16’ is such that the first spring members 16 and the second spring members 16’ touch or are very closely spaced such that they act as if touching. In these embodiments, the gap between the first spring members 16 and the second spring members 16’ may be between 0.01 mm to 2mm. In embodiments, the first spring members 16 and the second spring members 16’ are spaced such as the gap therebetween is from 0.01 mm to 1 mm, or 0.01 mm to 0.5mm. Suitably, the gap may be at least 0.01 mm, 0.1 mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm or above. Suitably, the gap may be at most 2mm, 1.9mm, 1 ,8mm, 1 ,7mm, 1 ,5mm, 1 ,4mm, 1 3mm, 1 2mm, 1 .1 mm or 1.0mm. In alternative embodiments, the first spring members 16 and the second spring members 16’ just touch each other (i.e. contact but impart no force against each other). Alternatively, in other embodiments the angle of each set of spring members 16, 16’ is chosen so that there is a biasing force created that acts between first spring members 16 and the second spring members 16’ when the product is assembled so as to remove or minimise any gap between the first spring members 16 and the second spring members 16’. In embodiments, the force therefore acting between first spring members 16 and the second spring members 16’ could be zero Newtons up to 20 Newtons. Suitably, the force is between 5 Newtons and 15 Newtons or 10 Newtons to 15 Newtons.

With the first spring members 16 and the second spring members 16’ touching, any gap between them is closed or minimised and the first spring members 16 and the second spring members 16’ effectively appear and act like a single unitary part. In this embodiment, the combined opening 13b, 13b’ is apparent as a single aligned opening created between the combination of the first spring members 16 and the second spring members 16’ which visually gives the user a clearer and definitive view of where to insert the needle into the device.

In use, and with reference to Figure 7, and in particular Figure 8a-8d, with regard to the push-fit fixing, a needle 110 of a syringe 111 is inserted into the aperture 13b/13b’ (Figure 8a) and pushed firstly through the first spring layer 15, then through the second spring layer 15’. When the first spring layer 15 and the second spring layer 15’ are in contact at least at the aligned opening then this process is simultaneous. For convenience, the device may be located in an upper surface of a container in which the needles are collected and the first spring layer 15 and the second spring layer 15’ will be in effect be upper and lower spring layers. As the needle 110 passes through the first and second spring layers 15, 15’ the spring members 16, 16’ of the spring layers 15, 15’ are deflected downwards, which effectively widens the opening 13b, 13b’ allowing the needle which typically has a diameter wider than the opening 13b, 13b’ in its resting state, to pass (Figure 8b). Once the needle has passed fully through the first and second spring layers 15, 15’, the spring members 16, 16’ are able to return, or spring back towards, or to, their initial position to re-narrow the opening 13b, 13b’ and surround the tip of the syringe 111 to which the needle 110 is removably attached. This may cause an audible click which alerts the user to the passage of the connector through the members. Once the needle of the syringe has passed fully through the first and second spring layers 15, 15’, the action of pulling the syringe back through the spring layers applies a force to the needle 110 that acts to separate it from the tip of the syringe 111 . As the syringe 111 is withdrawn by the user the resiliency of the spring layers 15, 15’ prevents or minimises further widening of the opening 13b, 13b’ preventing the needle from escaping the interior of the container, and minimising any risk of splashing of any liquid material in the needle 110. At no point during this procedure does the user have to bring his or her fingers close to the needle and moreover the action can be carried out using one hand only.

The method may also be applied to other removably needle types such as bayonet or screw-type needle fittings. In these embodiments, as the needle is inserted into the opening of the device the spring layers act to surround and grip the needle (Figure 8b) such that the syringe may be suitably manipulated, such as rotated, or pushed and rotated, to allow removal of the needle from the syringe. Once the needle is detached it may be pushed with the tip of the syringe fully through the aperture 13b/13b’ so that it drops into the container (not shown). The syringe may then be withdrawn and disposed off appropriately. In this embodiment, the sequence of events shown in Figure 8 would proceed as Figure 8a, then Figure 8b then Figure 8d.

The present invention can be incorporated into a wide variety of containers of different shapes and sizes. In embodiments, the container may be fixed to a surface via any suitable means such that it doesn’t move when the needle removal method is applied.

Examples

Example 1: Comparison of needle removal efficiency to the prior art device of GB 2544472 B

With a gap present between the first spring members 16 and the second spring members 16’ as in the prior art device described in GB 2544472B (as shown in Figure 10), an efficiency of 70% of effective first-time needle removal from the syringe is achieved. In contrast with the device 10 in accordance with the embodiment of the present invention shown in Figure 9 (middle) where the spring members 16, 16’ have a substantially constant angle of 5° and where the first spring members 16 and the second spring members 16’ contact each other with no gap but with no force between the two, the efficiency increased upwardly of 90%. Creating a compression force between the lower and upper spring members on assembly produced the most successful results with needle removal efficiency of 98%.

Example 2: Comparison of the angle of projection and the design of the angled section

The angle of projection of the spring members 16, 16’ also has a positive impact on the efficiency of the needle removal function by both reducing the insertion force of the needle as it is pushed into the product and increasing the ‘bite’ or biasing, removal force onto the needle or part thereof when the syringe is retracted from the device 10 by a user. Taking as a benchmark or reference point of when the spring members 16, 16’ are flat (Figure 9: top), as hereinbefore described. In this embodiment the inward force on the needle on entry is 100% and the force on the needle on exit is 100%.

In an embodiment when the spring members 16, 16’ have a uniform inward projection of 5° from flat across their entire length (Figure 9: middle) then the inward force on the needle on entry is reduced to an estimated 90% and the estimated force on the needle on exit is 110%.

In a further embodiment where on a central portion of the spring members 16, 16’ project inwardly at an angle of 20° from flat, the remainder of the spring members 16, 16’ being flat (Figure 9: bottom), then the inward force on the needle on entry is reduced to an estimated 60-70% and the estimated force on the needle on exit is 130-140%.

This leads to a particular advantage of the present invention of separating the needle part from the syringe part more effectively and also provides a greater level of safety as an easy locating/guiding feature when operating the device 10.

It will be recognised that the invention is not limited to the specific details described herein which are given by way of example only, and various modifications and alterations are possible within the scope of the invention.