Release mechanism for use with needle shielding devices

A needle-based medical device and method of manufacturing the same are disclosed. A needle device includes a hub having a longitudinal axis; a needle having a sharp distal tip; and a needle shield assembly associated with the needle and moveable from a non-shielding position to a shielding position. In the shielding position, the sharp distal tip is covered by at least part of the needle shield assembly. A latch is further provided for engaging with the hub when the needle shield assembly is in the non-shielding position; as well as a locking member operably connected to the needle shield assembly, and located at least partially within the hub when the needle shield assembly is in the non-shielding position. The latch and locking member lock the latch to the hub, such that when the needle shield assembly moves into the shielding position, the locking member moves generally proximally, unlocking the latch.

BACKGROUND OF THE INVENTION

The invention relates generally to needle-based medical devices. More particularly, the invention relates to a passive safety shield for a needle of a needle-based medical device which shields the needle prior to releasing from a device. Needle shielding devices come in a variety of forms that do not allow for easy and passive activation and disconnection from a hub, such as a catheter introducer hub. Furthermore, needle shielding devices protrude into the catheter introducer hub and occupy the volume of the female luer connector, thereby interfering with hemostatic valves and seals.

BRIEF DESCRIPTION OF THE INVENTION

A first aspect of the disclosure provides a needle device comprising a hub having a longitudinal axis; a needle having a sharp distal tip; a needle shield assembly associated with the needle and moveable from a non-shielding position to a shielding position in which the sharp distal tip is covered by at least part of the needle shield assembly; a latch engaging with the hub when the needle shield assembly is in the non-shielding position; and a locking member operably connected to the needle shield assembly, and located at least partially within the hub when the needle shield assembly is in the non-shielding position, thereby locking the latch to the hub, and such that when the needle shield assembly moves into the shielding position, the locking member moves generally proximally, thereby unlocking the latch.

A second aspect of the disclosure provides a needle device comprising: a hub comprising a luer connector with a luer thread and having a longitudinal axis; a needle having a sharp distal tip; a needle shield assembly associated with the needle and moveable from a non-shielding position to a shielding position in which the sharp distal tip is covered by at least part of the needle shield assembly, a latch engaging with the luer thread of the hub when the needle shield assembly is in the non-shielding position, a locking member operably connected to the needle shield assembly and located at least partially in the luer connector when the needle shield assembly is in the non-shielding position, thereby locking the latch to the hub, and such that when the needle shield assembly moves into the shielding position, the locking member moves axially.

A third aspect of the disclosure provides a method of manufacturng a needle assembly comprising: placing a blocking object in a carrier, wherein the carrier includes a flange disposed on a distal end thereof; inserting the carrier into a shroud; inserting the shroud into a housing until the proximal end of the shroud abuts a reduced diameter portion at a proximal end of the housing, wherein the housing includes a hooked member circumferentially extending from a portion of a distal end of the housing, and a first, distal opening and a second, proximal opening are provided through a wall of the housing; inserting a proximal end of a needle into an axial lumen of the carrier, thereby displacing the blocking object such that it protrudes at least partially through the proximal, second opening in the housing; affixing the proximal end of the needle to a needle hub; threading a catheter hub and a cannula over a distal end of the needle, wherein the catheter hub has a flanged proximal end; and engaging the hooked member with the flanged proximal end of the catheter hub, and inserting the flange disposed on the distal end of the carrier into the catheter hub, wherein the engaging and inserting the flange causes the blocking object to move distally such that it protrudes from the first, distal opening in the housing.

These and other aspects, advantages and salient features of the invention will become apparent from the following detailed description, which, when taken in conjunction with the annexed drawings, where like parts are designated by like reference characters throughout the drawings, disclose embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

As noted, a needle-based medical device including a needle shield30(FIG. 5) will be described with reference toFIGS. 1-15. At least one embodiment of the present invention is described below in reference to its application in connection with a needle-based medical device in the form of a catheter introducer. Although embodiments of the invention are illustrated relative to a needle-based medical device in the form of a catheter introducer, it is understood that the teachings are equally applicable to other needle-based medical devices including, but not limited to, syringes, blood collection devices, and other types of devices. Further, at least one embodiment of the present invention is described below in reference to a nominal size and including a set of nominal dimensions. However, it should be apparent to those skilled in the art that the present invention is likewise applicable to any suitable needle-based device. Further, it should be apparent to those skilled in the art that the present invention is likewise applicable to various scales of the nominal size and/or nominal dimensions.

With reference toFIGS. 1-3, one embodiment is illustrated including a needle device5in the form of a catheter introducer assembly including a hub10, a catheter cannula12, and an introducer needle14.

In the embodiment shown inFIG. 2, hub10includes a threaded proximal end11to which tubing and the like can be connected. Hub10also may include a female luer adapter13(FIGS. 3-4) into which a male component such as a blood sealing device15(FIGS. 5-10) such as a valve or septum can be placed within hub10. Although not shown, hub10may also include a port. Needle14includes a longitudinal axis17(FIG. 5), a sharp distal end16, and a proximal end18(FIG. 3).

As shown inFIGS. 3-5, proximal end18of needle14is secured to a distal end of needle hub20, e.g., by glue using a glue well, which is described in co-pending US patent applications publications No. 2009/0036843A1 and No. 2009/0032185A1, each of which are incorporated herein by reference. Needle hub20may be secured at its proximal end to a handle74. Needle14, hub10, cannula12, and needle hub20may be substantially coaxial.

Referring toFIGS. 3-10, needle shield assembly30and a latch32are provided for shielding distal tip16of needle14. Needle shield assembly30includes a needle blocking object39, and a carrier34for carrying needle blocking object39. Needle shield assembly30may further include an external shroud36disposed about carrier34and within latch32, and a spring41for biasing needle blocking object39as described herein.

Needle shield assembly30is movable between a non-shielding position (FIGS. 3,5-6) and a shielding position (FIGS. 7-10).FIGS. 5-10illustrate one embodiment of progression from the non-shielding position, in which latch32and locking member54retain the needle shield assembly30in engagement with hub10, to the shielding position, in which needle shield assembly30prevents emergence of sharp distal end16of needle14therefrom.

With reference toFIG. 5, needle shield assembly30will now be described. Needle shield assembly30includes carrier34, which may be substantially cylindrical and includes an axial lumen48substantially aligned with a longitudinal axis of the device. Axial lumen48accommodates needle14and allows carrier34to slide along needle14. Carrier34may further include an internal member including a channel50or other structure for limiting radial movement of needle blocking object39toward the longitudinal axis of needle14in the shielding position of needle shield assembly30. In the illustrative embodiment, channel50is shaped and dimensioned such that needle blocking object39can be carried and can moved along channel50(FIGS. 5-10) and dropped into place in the shielding position (FIGS. 7-10). In the shielding position, needle blocking object lies at least partially across axial lumen48, thereby blocking emergence of sharp distal end16of needle14. In still further embodiments, carrier34may include an external shroud36. Shroud36may be made of metal, and may be substantially cup-shaped, such that it substantially encases carrier34, but is open at the distal end60. Carrier34can thus be inserted into shroud36such that a proximal end of the carrier abuts the inside of proximal end56of shroud36. Carrier34also includes a first opening37through which a portion of needle blocking object projects39while resting in channel50in a non-shielding position. In embodiments including shroud36, opening37extends through a thickness of a wall of shroud36.

A spring41may further be provided for biasing needle blocking object39. Spring41may be disposed about carrier34, and within shroud36, such that it abuts needle blocking object39. Spring41tends to urge needle blocking object distally and into lumen48, toward the axis of the device. Spring41may be, for example, a coil spring, although other types of springs may be used as known in the art.

A locking member54may be operably coupled to a distal end52of carrier34, and is dimensioned to engage an internal surface of hub10in the non-shielding position. Locking member54may be a flange or flanged member. In some embodiments, the engagement between an internal surface of hub10and locking member54may include insertion of at least a portion of locking member54into hub10as shown inFIG. 5. As noted, hub10may include a female luer adapter13, which engages with a close slip fit with locking member54.

In an embodiment, at a proximal end of axial lumen48, a hole or opening58(FIGS. 5-6) may be provided in carrier34including shroud36. Hole58is dimensioned to accommodate the outer diameter of needle14. Needle14may include a crimp19, shown inFIG. 6, which provides an area of needle14having enlarged diameter in at least one radial direction. Opening58does not accommodate crimp19, so that as shown inFIG. 8, crimp19provides a stop which engages an inside of proximal end56of shroud36. Crimp19is positioned along needle14such that when crimp19reaches proximal end56of shroud36, sharp distal tip16of needle14is proximal of needle blocking object39, and therefore shielded.

As further shown inFIG. 5, carrier34may be disposed substantially within latch32, the latter of which engages hub10to needle shield assembly30in the non-shielding position. Latch32includes a housing33having a proximal end46and a distal end44, the latter of which is coupled to a hooked latch member38. Latch member38and housing33are shown inFIG. 5as being a single, continuous member, but embodiments in which latch member38and housing33are separate members that are operably connected are also considered part of the invention.

Latch member38is shaped and dimensioned to engage with flanged proximal end11of hub10. As shown inFIGS. 3 and 12, latch member38includes a hooked leg extending over a flange on flanged proximal end11of hub10. In one embodiment, hooked latch member38includes a first member81extending radially outward relative to housing33, a second member82extending distally from a radially outward end of first member81in a direction substantially parallel to housing33, and a third member83extending radially inward from the distal end of second member82, forming a distal restraining surface of latch32. In one embodiment, shown inFIG. 5, second member82and third member83may be orthogonal. In an alternative embodiment, shown inFIG. 6, the angle α formed by second member82and third member83may be other than orthogonal, e.g., about 135°, such that third member83provides a beveled edge on the distal restraining surface of latch32for releaseably engaging flanged proximal end11of hub10. With reference toFIG. 12, in one embodiment, a first distance A between a radially inward end of the leg of latch member38and distal end52of locking member54as positioned within hub10is less than a second distance B between a proximal-most point on an internal diameter of hub10and a distal-most point on an external diameter of the flange on proximal end11of hub10. The above-described angled structure may be provided to enable smooth disengagement of hook member38and flanged proximal end11.

In some embodiments, flanged proximal end11of hub10may be threaded. Latch member38may have an extent that varies between about 90° and 180° circumferentially such that latch32can engage hub10regardless of position relative to threads on flanged proximal end11of hub10, and still be able to freely disengage from hub10in the shielding position.

Latch32further includes a first opening40extending through a wall thereof. In the non-shielding position, shown inFIGS. 5-6, opening37in external shroud36substantially aligns with first opening40in latch32in the non-shielding position, such that at least a portion of needle blocking object39protrudes through opening37and into first opening40. The protruding portion of needle blocking object39engages a proximal edge43of first opening40in latch32to engage locking member54with the internal surface of hub10and maintain latch32in engagement with hub10.

FIGS. 7-10illustrate the continued progression of movement from the non-shielding position to the shielding position. Upon movement of the needle shield assembly30from the non-shielding position to the shielding position, needle blocking object39exits first opening40in latch32and opening37in carrier34. Needle blocking object39does so under a force from spring41, which biases needle blocking object39distally and toward longitudinal axis17of needle14. Needle blocking object39at least partially enters axial lumen48, preventing emergence of sharp distal end16of needle14from carrier34. Locking member54disengages from hub10and moves proximally within latch32, allowing latch32to disengage hub10from needle shield assembly30.

Latch32may further include a second opening42through a wall of housing33. Second opening42is disposed proximally of first opening40.

In further embodiments, as shown inFIGS. 5-10, latch32may include a first protrusion62on an inner surface of housing33. A second protrusion64may be disposed on an outer surface of carrier34. Where carrier34includes external shroud36encasing carrier34, second protrusion64may be on, or part of, an outer surface of external shroud36. First protrusion62interacts with second protrusion64as needle shield assembly30moves proximally from a non-shielding position to a shielding position such that a pull-out force required to move carrier34proximally relative to latch32is greater than a frictional force between needle blocking object39and needle14. This structure prevents wedging of blocking object39and needle14, as blocking object39can roll under proximal edge43of opening40in latch32and wedge against needle14.

As shown inFIGS. 1-5, needle hub20may be disposed about latch32. Needle14is coupled to needle hub20such that when needle hub20is pulled in a proximal direction, needle14moves proximally toward a shielding position. Needle hub20may include a boss21that abuts proximal end56of shroud36.

When the needle shield assembly is in its fully assembled, non-shielding state (FIGS. 5-6) locking member54fits closely into female luer13in hub10. Latch32, and particularly latch member38, is hooked over proximal end11of hub10. The fit between latch member38and proximal end11of hub10is loose, such that the pull-off force is low. Needle blocking object39partially protrudes through opening37and into first opening40in latch32. Needle blocking object39abuts distal edge59of opening37and proximal edge43of opening40, and is held in place by abutment with the outer surface of needle14. Locking member54cannot escape hub10due to needle blocking object39abutting with proximal edge43of first opening40.

When needle shield assembly30is deployed (i.e., needle14is withdrawn from hub10and carrier34moves into the shielding position shown inFIGS. 7-10), the user pulls needle hub20in a proximal direction, thus drawing needle14along cannula12and carrier34, until crimp19abuts opening58in shroud36. At that point, sharp distal tip16of needle14has passed needle blocking object39, and needle blocking object39has moved into lumen48, urged there by spring41(turning about distal edge59of opening37in shroud36), thereby blocking the path of sharp distal tip16of needle14, should needle14move in the distal direction. Locking member54can now move out of hub10and deeper, or proximally, into latch32, since needle blocking object39is no longer obstructed by proximal edge43of first opening40. This movement also releases latch member38, so it can disengage with proximal end11of hub10.

The combination of needle blocking object39, needle14, openings37in shroud36and first opening40in latch32, and locking member54(on carrier34) forms a locking assembly, which secures needle shield assembly30to hub10. This locking assembly is only released when sharp distal tip16of needle14has passed needle blocking object39and is thus shielded, thereby providing a passive safety shield which cannot disengage from hub10prior to shielding sharp distal tip16of needle14. Needle shield assembly30is substantially external of hub10in this position, thus providing space within hub10for a blood sealing device15, for example a septum or a luer-actuated valve, as well as a side port.

The combination of crimp19and opening37in shroud36prevents proximal movement of sharp distal tip16of needle14. This and other ways of preventing proximal movement of the needle14are shown in co-pending US patent applications No. 2008/0119795 A1, No. 2009/0137958 A1 and 2009/0249605 A1, each of which are incorporated herein by reference.

A method of assembling or manufacturing the device will now be described.

With reference toFIG. 13, a needle blocking object39may be placed in carrier34. Carrier34may include: a locking member54on, or engaged with, a distal end52thereof, and a channel50for carrying needle blocking object39. Carrier34may be inserted into shroud36until a proximal end of carrier34abuts proximal end56of shroud36. Shroud36is then inserted into latch32until proximal end56of shroud36abuts a reduced diameter portion at a proximal end of latch32. Latch32includes a latch member38extending from a portion of a distal end44of latch32. Latch32further includes a first opening40through a wall thereof, and a second opening42through a wall thereof, located proximally of first opening40.

Proximal end18of needle14is inserted into distal end52of axial lumen48in carrier34. Needle14displaces needle blocking object39such that it protrudes at least partially into second opening42in latch32, as shown inFIG. 13. Proximal end18of needle14is then affixed to needle hub20, for example, with glue as shown inFIGS. 3 and 5. Hub10may have a flanged proximal end11. Latch member38is engaged with flanged proximal end11of hub10as shown inFIG. 14. Hub10and cannula12are then threaded over distal tip16of needle14. Needle shield assemby30is then inserted into needle hub20, causing boss21to push locking member54distally into hub10, slip fitting closely into it as hown inFIG. 5.

Hub10may include a female luer adapter13therein. The foregoing engagement of latching member38with flanged proximal end11of hub10, and the insertion of locking member54into hub10cause needle blocking object39to move distally within carrier34and out of second opening42(FIGS. 14-15), such that it protrudes into first opening40in latch32as inFIG. 5. Latch32may be configured to flex or expand slightly to allow needle blocking object39to snap from second opening42to first opening40. Needle shield assembly30is thus locked onto hub10and is ready for deployment as described herein.

As used herein, the terms “first,” “second,” and the like, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another, and the terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., includes the degree of error associated with measurement of the particular quantity). The suffix “(s)” as used herein is intended to include both the singular and the plural of the term that it modifies, thereby including one or more of that term (e.g., the metal(s) includes one or more metals). Ranges disclosed herein are inclusive and independently combinable (e.g., ranges of “up to about 25 mm, or, more specifically, about 5 mm to about 20 mm,” is inclusive of the endpoints and all intermediate values of the ranges of “about 5 mm to about 25 mm,” etc.).

While various embodiments are described herein, it will be appreciated from the specification that various combinations of elements, variations or improvements therein may be made by those skilled in the art, and are within the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.