U.S. patent application number 10/650419 was filed with the patent office on 2004-09-23 for lockable safety shield assembly for a prefillable syringe.
Invention is credited to Imbert, Claude, Jansen, Hubert.
Application Number | 20040186440 10/650419 |
Document ID | / |
Family ID | 25476476 |
Filed Date | 2004-09-23 |
United States Patent
Application |
20040186440 |
Kind Code |
A1 |
Jansen, Hubert ; et
al. |
September 23, 2004 |
Lockable safety shield assembly for a prefillable syringe
Abstract
A lockable safety shield assembly for a prefillable syringe is
provided. The design of the lockable safety shield assembly
enhances pharmaceutical manufacturers' ease of assembling the
various components as part of its filling or processing of the
prefillable syringes in normal practice, while at the same time
minimizes difficulties in mating parts made from different
materials. A tube is placed around the outside surface of the
syringe barrel and affixed thereto. A collar is provided on the
tube adjacent the distal end of the syringe barrel. A safety shield
is axially slidable over the tube between a retracted position,
wherein the distal end of the piercing element associated with the
prefillable syringe is exposed, and an extended position, wherein
the safety shield is locked to the collar to protectively cover the
distal end of the piercing element. The safety shield includes
locking structure configured so that the shield can be easily
fitted over the tube. The locking structure includes at least one
deflectable arm provided on the body of the shield. The deflectable
arm includes a proximal end deflectable towards the interior of the
shield. A stop member is provided on the interior of a shield in
spaced relation to the proximal end of the deflectable arm. A ring
is axially slidable over the shield to deflect the arm towards the
interior of the shield to activate the locking structure. The
safety shield is slid distally by an end user such that the collar
is lockingly retained between the stop member and the proximal end
of the deflectable arm. The collar, the stop member, and the
deflectable arm may be configured to provide tactile as well as
audible indication of locking to the end user.
Inventors: |
Jansen, Hubert; (Poisat,
FR) ; Imbert, Claude; (La Tronche, FR) |
Correspondence
Address: |
DAVID W. HIGHET, VP AND CHIEF IP COUNSEL
BECTON, DICKINSON AND COMPANY
1 BECTON DRIVE, MC 110
FRANKLIN LAKES
NJ
07417-1880
US
|
Family ID: |
25476476 |
Appl. No.: |
10/650419 |
Filed: |
August 28, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10650419 |
Aug 28, 2003 |
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08941448 |
Sep 30, 1997 |
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6004296 |
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Current U.S.
Class: |
604/198 |
Current CPC
Class: |
A61M 5/3243 20130101;
A61M 5/502 20130101; A61M 5/3271 20130101; A61M 2005/3109 20130101;
A61M 5/3135 20130101; A61M 5/3202 20130101; A61M 2205/581 20130101;
A61M 2205/582 20130101; A61M 2005/3247 20130101 |
Class at
Publication: |
604/198 |
International
Class: |
A61M 005/32 |
Claims
1. A medical device, comprising: a barrel having proximal and
distal ends; a tube secured about the barrel, the tube having a
collar positioned adjacent the distal end of the barrel, the collar
having an edge; and a shield mounted about said tube and axially
movable between a retracted position, wherein the distal end of the
barrel is exposed, and an extended position, wherein the distal end
of the barrel is covered, the shield having a proximal end, a
distal end, and a circumferential sidewall therebetween, the
circumferential sidewall having an outside surface and an inside
surface; user-activatable locking means to secure the shield in the
extended position, the user activatable locking means comprising at
least one deflectable arm having a distal end mounted with the
circumferential sidewall and a proximal end deflectable towards the
interior of the shield, said at least one arm having a free
position wherein the arm is substantially coplanar with the
circumferential sidewall of the shield, and a locking position,
wherein the arm is deflected towards the interior of said shield so
that the proximal end is positioned towards the interior of the
shield, at least one stop member mounted to the interior surface of
the shield adjacent the proximal end of the shield to define a gap
between the stop member and the proximal end of the deflectable
arm, and a ring axially slidable around the outside surface of the
shield between a first position wherein the ring is spaced away
from the at least one deflectable arm and a second position wherein
the ring is positioned against said at least one deflectable arm to
secure the arm in the locking position.
2. The medical device of claim 1, wherein the barrel includes a
piercing element at its distal end, wherein the piercing element is
exposed when the shield is in the retracted position, and wherein
the piercing element is protectively covered when the shield is in
the extended position.
3. The medical device of claim 1, wherein a flange is provided
adjacent the proximal end of the barrel, the tube secured to the
barrel at the flange of the barrel.
4. The medical device of claim 1, wherein said ring is secured to
the distal end of the shield by a user-severable connection in the
first position, wherein an end user may sever the user-severable
connection to axially slide the ring to the second position.
5. The medical device of claim 1, wherein the stop member includes
a proximally-facing sloped surface and a distally facing stop
surface, the gap defined between said stop surface and the proximal
end of said at least one deflectable arm.
6. The medical device of claim 1, wherein said deflectable arm
comprises structure for retaining the ring in the second
position.
7. The medical device of claim 6, wherein the structure for
retaining comprises a distal abutment and a proximal abutment
spaced from said distal abutment, wherein said ring is retained in
the space between said proximal and distal abutments.
8. The medical device of claim 7, wherein the space between said
proximal and distal abutments is raised from the surface of said at
least one deflectable arm, wherein said space is substantially
co-planar with the circumferential sidewall of the shield when said
deflectable arm is in the locking position.
9. The medical device of claim 7, wherein said distal abutment
includes a distally-facing sloped surface, wherein said ring is
urged over the distally-facing sloped surface of the distal
abutment into said second position.
10. The medical device of claim 1, wherein said shield further
comprises a second stop located on the interior surface of the
shield adjacent the distal end, said second stop engageable with
the collar when said shield is in the retracted position.
11. The medical device of claim 10, further comprising a third stop
located on the interior surface of the shield proximally of the
second stop, wherein the edge of the collar is retained between the
second and third stops when said shield is in the retracted
position.
12. The medical device of claim 1, wherein a locking tooth is
provided on the edge of the collar.
13. The medical device of claim 12, wherein the proximal end of the
at least one deflectable arm is oriented for locking engagement
with the locking tooth of the collar.
14. A medical device, comprising: a barrel having proximal and
distal ends; a piercing element extending from the distal end of
the barrel and having a distal tip; a flange provided adjacent the
proximal end of the barrel; a tube mounted about the barrel and
secured to the flange, the tube having a collar positioned adjacent
the distal end of the barrel, the collar having a side portion and
a circumferential edge; and a shield mounted about said tube and
axially movable between a retracted position, wherein the distal
tip of the piercing element is exposed, and an extended position,
wherein the distal tip of the piercing element is covered, said
shield having a proximal end, a distal end, and a circumferential
sidewall therebetween, the circumferential sidewall having an
outside surface and an inside surface, the shield including user
activatable locking means to secure the shield in the extended
position, the user activatable locking means comprising at least
one deflectable arm having a distal end mounted with the
circumferential sidewall, a proximal end deflectable towards the
interior of the shield, and an outside surface therebetween, the
proximal end of the deflectable arm defining an edge for engaging
said collar, said at least one arm having a free position wherein
the outside surface of said arm is substantially coplanar with the
circumferential wall of the shield, and a locking position, wherein
said arm is deflected towards the interior of said shield so that
said edge is positioned towards the interior of the shield, said
deflectable arm including a pair of abutments on the outside
surface spaced apart from one another, at least one stop member
mounted to the interior surface of the shield adjacent the proximal
end of the shield to define a gap between the stop member and the
proximal end of the deflectable arm, and a ring retained to the
shield by a user-severable connection, said ring axially slidable
around the outside surface of the shield between a first position
wherein the ring is spaced away from the at least one deflectable
arm and a second position wherein the ring is positioned between
the pair of abutments on said at least one deflectable arm to
secure the arm in the locking position, wherein the ring is slid
proximally along the shield until the ring is positioned between
the pair of abutments, and the shield thereafter urged distally so
that the circumferential edge of the collar enters into the gap
defined between the stop member and the proximal end of the arm so
that the edge of the arm engages the collar.
15. The medical device of claim 14, wherein a locking tooth is
provided on the circumferential edge of the collar.
16. The medical device of claim 15, wherein the edge of the arm is
oriented for locking engagement with the locking tooth of the
collar.
17. The medical device of claim 16, wherein the edge is canted.
18. The medical device of claim 14, wherein said stop member
includes a proximally-facing sloped surface, wherein said shield is
slidable proximally over said collar to place the shield in said
retracted position.
19. The medical device of claim 14, further comprising at least one
slit in said circumferential sidewall intermediate the proximal end
of the shield the proximal edge of the deflectable arm.
20. The medical device of claim 14, wherein the circumferential
sidewall defines a thickness between the inside surface and the
outside surface, wherein the thickness of the sidewall adjacent the
proximal end of the shield is less than the thickness of the
sidewall intermediate the proximal and distal ends of the
shield.
21. The medical device of claim 14, wherein the pair of abutments
on the at least one deflectable arm includes a proximal abutment
and a distal abutment, the distal abutment including a
distally-facing sloped surface to facilitate passage of the ring
over the distal abutment for placement between the pair of
abutments.
22. The medical device of claim 14, wherein the edge of said at
least one deflectable arm is shaped so that it is oriented parallel
to the side portion of said collar when the deflectable arm is in
said locked position.
23. The medical device of claim 14, wherein said shield further
comprises a second stop located on the interior surface of the
shield adjacent the distal end, said second stop engageable with
the side portion of the collar when said shield is in the retracted
position.
24. The medical device of claim 23, further comprising a third stop
located on the interior surface of the shield proximally of the
second stop, wherein the collar is retained between the second and
third stops when said shield is in the retracted position.
25. The medical device of claim 14, wherein said third stop
comprises a proximally-facing sloped surface to facilitate passage
of ring over said third stop as the shield is positioned towards
its retracted position.
26. The medical device of claim 21, wherein the space between said
proximal and distal abutments is raised from the surface of said at
least one deflectable arm, wherein said space is substantially
co-planar with the circumferential sidewall of the shield when said
deflectable arm is in the locking position.
27. The medical device of claim 26, wherein the space between said
proximal and distal abutments is sloped, wherein the space is
substantially co-planar with the circumferential sidewall of the
shield when said deflectable arm is in the locking position.
28. The medical device of claim 14, wherein the user-severable
connection comprises one or more thinned sections of material
between said ring and the distal end of the shield.
29. The medical device of claim 4, wherein the user-severable
connection comprises one or more thinned sections of material
between said ring and the distal end of the shield.
30. A medical device, comprising: a barrel having proximal and
distal ends; a piercing element extending from the distal end of
the barrel and having a distal tip; a tube attached about the
outside surface of the barrel, the tube having a collar positioned
adjacent the distal end of the barrel, the collar having an edge
and a locking tooth defined at the edge; and a shield mounted about
said tube and axially movable between a retracted position, wherein
the distal tip of the piercing element is exposed, and an extended
position, wherein the distal tip of the piercing element is
covered, the shield having a proximal end, a distal end, and a
circumferential sidewall therebetween, the circumferential sidewall
having an outside surface and an inside surface; user-activatable
locking means to secure the shield in the extended position, the
user activatable locking means comprising at least one deflectable
arm having a distal end mounted with the circumferential sidewall
and a canted proximal end deflectable towards the interior of the
shield for locking engagement with the locking tooth of the collar,
the at least one arm having a free position wherein the arm is
substantially coplanar with the circumferential sidewall of the
shield, and a locking position, wherein the arm is deflected
towards the interior of said shield so that the proximal end is
positioned towards the interior of the shield, at least one stop
member mounted to the interior surface of the shield adjacent the
proximal end of the shield and having a canted stop surface, the
stop member placed on the shield to define a gap between the canted
stop surface and the canted proximal end of the deflectable arm,
and a ring axially slidable around the outside surface of the
shield between a first position wherein the ring is spaced away
from the at least one deflectable arm and a second position wherein
the ring is positioned against said at least one deflectable arm to
secure the arm in the locking position, wherein after the ring has
been placed in the second position, the shield is urged distally so
that the locking tooth enters into the gap between the canted stop
surface and the canted proximal end of the arm to lock the tooth in
the gap.
31. The medical device of claim 30, wherein an audible indication
is produced as the locking tooth enters the gap.
32. The medical device of claim 30, wherein a tactile indication is
produced as the locking tooth enters the gap.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 08/941,448.
FIELD OF THE INVENTION
[0002] The invention relates to a lockable safety shield assembly
for a prefillable syringe, and more particularly, to a lockable
safety shield assembly for a prefillable syringe which is easily
attached to a prefillable syringe and which can be subsequently
activated by an end-user to form a locking mechanism for the
shield.
BACKGROUND
[0003] As is known in the art, syringes are medical delivery
devices utilizable to administer a medicament to a patient.
Syringes are normally provided in prefillable form, wherein a set
dosage of medicament can be filled into the syringe by a
pharmaceutical manufacturer for distribution to the end user, or
they are empty and intended to be filled by the end user from a
vial or other source of medicament at the time administration of
the medicament is desired.
[0004] Syringes typically include a barrel portion adapted to
retain the medicament. The distal end of the barrel is normally
configured to mate with a conventional piercing element, such as a
pointed needle cannula made of steel or like material or a blunt
ended cannula formed of plastic, to deliver the medicament
contained in the barrel. A plunger rod is inserted through the open
distal end of the syringe barrel and, through its engagement with
an elastomeric or rubber-like stopper element fitted in a
fluid-tight manner within the interior of the barrel, a user can
apply manual force to the plunger to deliver the medicament through
the piercing element.
[0005] More typically the case with pointed needle cannulae,
accidental needle sticks that occur after the needle cannula has
been used generally pose a greater health risk. To avoid such
accidents, many prior art hypodermic syringes include a rigid
cylindrical safety shield telescoped over the syringe barrel. The
prior art safety shield can be slid from a proximal position where
the needle cannula is exposed for use, to a distal position where
the safety shield protectively surrounds the needle cannula.
[0006] Most prior art hypodermic syringes with cylindrical safety
shields telescoped over the syringe barrel include structure for
locking the safety shield in its distal position. Examples of such
structures are found, for instance, in U.S. Pat. Nos. 5,342,309 and
5,385,555 to Hausser and U.S. Pat. No. 5,304,149 to Morigi.
[0007] While generally suitable for the tasks employed, further
improvements are still being sought. For instance, where the
syringe is prefillable by a pharmaceutical manufacturer, it would
be beneficial to incorporate improvements into the locking
structure employed with the safety shields to better facilitate a
pharmaceutical manufacturer's processing of the various components
associated with the syringe barrel and safety shield. These
improvements should also facilitate the end user's normal use of
the prefillable syringe and easy activation of the safety shield
once safe disposal of the syringe is desired. Moreover, most of the
prior art approaches focus their efforts on employing a plastic
collar element on some distal portion of the syringe barrel, with
the shield locking onto the collar. While a valid approach, because
many of the prefilled syringes currently in use are made of glass,
it can be difficult to assemble the plastic collar element onto the
syringe barrel. Accordingly, it would be useful to design a
structure whereby the collar were incorporated as part of the
shield structure itself.
SUMMARY OF THE INVENTION
[0008] A lockable safety shield assembly for prefillable syringes
is provided. The lockable safety shield is designed to facilitate a
pharmaceutical manufacturer's assembly of the various components
associated with the lockable safety shield onto the syringe in
conjunction with how the syringes are normally processed by the
pharmaceutical manufacturer. The locking structure associated with
the safety shield of the present invention may be designed such
that it will not interfere with easy assembly by the pharmaceutical
manufacturer, but which can be easily activated by an end user to
facilitate safe covering of the distal end of a piercing element
once the prefillable syringe has been used.
[0009] The assembly includes a tube mounted about the outside
surface of the syringe barrel. The tube can be locked, for
instance, to the flange provided about the proximal end of the
syringe barrel. The tube features a collar positioned adjacent the
distal end of the syringe barrel. The collar can be configured as a
flat, disk-like structure formed in an annular manner about the
outside of the tube.
[0010] A safety shield is coaxially mounted over the tube. The
safety shield is axially movable between a retracted position,
wherein the distal tip of a piercing element affixable to the
barrel is exposed, and an extended position, wherein the distal tip
of the piercing element will be covered. The safety shield includes
a proximal end, a distal end, and a circumferential sidewall
therebetween. The circumferential sidewall has an outside surface
and an inside surface. Particularly, the shield is provided with
user-activatable locking structure to secure the shield in its
extended position respective of the syringe.
[0011] In one configuration, the locking structure includes at
least one deflectable arm incorporated as part of the structure of
the sidewall. The deflectable arm includes a distal end mounted
with the circumferential sidewall, and a proximal end which is
deflectable towards the interior of the shield. At least one stop
member is mounted to the interior surface of the shield and spaced
a distance from the proximal end of the deflectable arm to define a
gap between the stop member and the proximal end of the deflectable
arm. The deflectable arm has a free position, wherein the outside
surface of the arm is substantially co-planar with the outside
surface of the circumferential sidewall, and a locking position,
wherein the deflectable arm is urged towards the interior of the
shield so that the proximal end of the deflectable arm is
positioned towards the interior of the shield.
[0012] Means are provided on the shield to activate the locking
structure. In one configuration, a circumferential ring is axially
slidable about the outside surface of the shield between a first
position, wherein the ring is spaced away from the deflectable arm,
and a second position, wherein the ring is positioned against the
at least one deflectable arm to secure the arm in the locking
position. The ring may be secured to the distal end of the shield
by a user-severable connection. The user-severable connection may
entail, for instance, one or more frangible sections of material
provided between the ring and the distal end of the shield. A pair
of spaced abutments may be provided on the outside surface of the
deflectable arm to retain the ring in its second position.
[0013] In practice, the safety shield assembly is typically
preassembled by the syringe manufacturer and supplied to the
pharmaceutical manufacturer in a sterile state, ready for
attachement to the prefillable syringe once it has been filled with
a desired drug.
[0014] After the syringe has been filled with the drug and
otherwise subjected to various processing operations, such as
various particulate inspection operations, labelling operations,
plunger rod assembly operations, or the like, the safety shield
assembly can be easily fitted to the syringe. The tube is fitted
about the syringe barrel and clipped onto the flange of the syringe
barrel. In the preassembled state, the shield located respective of
the tube such that the shield will be placed in a retracted
position vis-a-vis the piercing element. Various structures
associated with the tube may be provided with sloped surfaces to
ensure smooth placement of the safety shield assembly over the
syringe flange.
[0015] Subsequent to placing the shield assembly onto the syringe
barrel, the locking structure must be activated. The locking
structure is activated by detaching the ring from its
user-severable connection, and sliding the ring proximally so that
it is engaged between the abutments provided on the deflectable
arm. If desired, the device may be shipped by a pharmaceutical
manufacturer to an end user with the ring connected to the shield
by its user-severable connection, so that the end-user himself
activates the locking structure. Alternately and preferably, the
pharmaceutical manufacturer activates the locking structure as part
of the assembly process, such that the filled syringe with safety
shield assembly is shipped to an end-user with the locking
structure already activated.
[0016] After the syringe has been used to administer an injection,
the shield is slid distally over the tube. The collar will be
captured between the proximal end of the deflectable arm and the
stop member in order to lock the shield in its extended position.
In a preferred embodiment, the deflectable arm, the collar, and the
stop member may be configured to provide audible as well as tactile
indication to the end user that the shield has been securely locked
with the collar.
[0017] In a preferred embodiment, at least two deflectable arms are
provided. The two deflectable arms are located on diametrically
opposite sides of the shield. Correspondingly, two stop members are
provided to interact with the two deflectable arms. When viewed
along the central axis of the shield, the stop members can be
circumferentially aligned with a respective proximal end of the
deflectable arms, or they can be circumferentially offset from a
respective proximal end.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The invention will now be described in greater detail by way
of reference to the appended drawings, wherein:
[0019] FIG. 1 depicts, in perspective view, a lockable safety
shield assembly of the present invention mounted to a syringe;
[0020] FIG. 2 is an exploded perspective view of the lockable
safety shield assembly of FIG. 1;
[0021] FIG. 3 is a cut-away view of the lockable safety shield of
the present invention being mounted over the tube and the syringe
barrel;
[0022] FIG. 4 is a cross-sectional view of the lockable safety
shield assembly of the present invention subsequent to mounting to
the syringe;
[0023] FIG. 5 is a cross-sectional view of the lockable safety
shield assembly of the present invention after an end user has
activated the locking mechanism;
[0024] FIG. 6 is a cross-sectional view of the lockable safety
shield assembly of the present invention after it has been urged in
a distal direction by an end-user to protectively cover the needle
cannula;
[0025] FIG. 7 is partial cross-sectional view of the lockable
safety shield assembly of the present invention illustrating
activation of the locking mechanism;
[0026] FIG. 8 is a partial cross-sectional view of the lockable
safety shield assembly of the present invention interacting with
the collar located on the tube;
[0027] FIG. 9 is an end elevational view of the lockable safety
shield assembly in accordance with the present invention; and
[0028] FIG. 10 is a partial cross-sectional view of a preferred
manner of configuring the collar in accordance with the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] A convention utilized throughout this description is that
the term "distal" refers to the direction furthest from a
practitioner, while the term "proximal" refers to the direction
closest to a practitioner.
[0030] Turning now to the drawings, wherein like numerals denote
like components, FIGS. 1-4 depict one embodiment of a lockable
safety shield assembly 30 in accordance with the present invention.
The lockable safety shield assembly 30 in accordance with the
present invention can be provided in conjunction with a prefillable
syringe 10. As illustrated in FIGS. 1 and 2, prefillable syringe 10
includes a barrel 16 characterized by a proximal end 14, a distal
end 12, and a hub 24 provided adjacent the distal end. A flange 18
may be provided about the proximal end, with a plunger rod 20
inserted through proximal end 14. Plunger rod 20 is attached to a
stopper 22 used for urging fluid through barrel 16. Fluid is
emitted or aspirated via a fluid path, structured at distal end 12
of the syringe, that communicates with interior portions of barrel
16. For instance, if the pre-fillable syringe is configured as a
luer lock syringe, the fluid path is configured as a luer tip (not
shown) provided at distal end 12. Here, pre-fillable syringe 10 is
illustrated with a fluid path configured as a piercing element 26,
such as a pointed needle cannula. Piercing element 26 is
characterized by a distal end 28.
[0031] The lockable safety shield assembly 30 in accordance with
the present invention includes a tube 200 which is mounted about
barrel 16 of the syringe. The tube 200 features a proximal end 204,
a distal end 202, and a circumferential sidewall 206 therebetween.
A flange structure 208 is provided adjacent proximal end 204 of the
tube. As best seen in FIG. 3, flange structure 208 includes a lip
210 sized to lockingly engage flange 18 of the syringe barrel when
tube 200 is placed over barrel 16. Adjacent distal end 202 of the
tube there is provided a collar 32. Collar 32 can be formed as a
disk-like structure characterized by an edge 34 and a side portion
36. Collar 32 has a thickness "e" and is characterized by a maximum
diameter "g". Collar 32 may be provided as part of the structure of
tube 200. Alternately, as the skilled artisan will appreciate,
collar 32 may be separately supplied and retained to the tube by
friction fit, adhesives, mechanical means, or like structure. If
desired, edge 34 can display one or more raised nubs 39 having
grooves 40. Grooves 40 can be aligned with complementary rails (not
shown) provided on an interior portion of safety shield 42 for
aligning the safety shield during the assembly process.
[0032] For purposes of clarity, FIGS. 1-6 depict collar 32 as
having a rectangular cross-section, with side portion 36 displaying
relatively flat walls that are directly linked to edge 34. If so
desired, collar 32 can be configured in this manner to construct a
lockable safety shield assembly in accordance with the present
invention. However, FIG. 10 depicts a preferred way for configuring
the collar (here designated by the numeral 32a) so to provide
better audible as well as tactile indication that shield 42 has
been locked to the collar, as well as to enhance locking action
between the shield and the collar, as will be further
explained.
[0033] Referring then to FIG. 10, as before, collar 32a includes an
edge 34 and a side portion 36. However, here, side portion 36 is
not completely flat. Rather, when viewed in cross-section, edge 34
and side portion 36 are linked by a locking tooth 34a. Locking
tooth 34a features a distally-facing canted edge 36a and a
proximally-facing canted edge 36b. Each of canted edges 36a, 36b of
the locking tooth terminate at a shelf 37 that intersects with side
portion 36. As before, if desired, grooves (not shown) can be
provided on edge 34, for the purposes previously explained. As
before, collar 32a includes a thickness "e" and a maximum diameter
"g". Locking tooth 34a includes a maximum width "q" which need not
be equal to thickness "e" displayed by collar 32a.
[0034] Safety shield 42 is characterized by a proximal end 44, a
distal end 45, and a circumferential sidewall 46 therebetween.
Circumferential sidewall 46 includes an outside surface 48 and an
inside surface 49. Outside surface 48 is characterized by a
diameter "N". Shield 42 is slidable both over tube 200 and collar
32, and thus over syringe barrel 16, between a retracted position
(FIGS. 1, 4 and 5), wherein distal tip 28 of piercing element 26 is
exposed, and an extended position (FIG. 6), wherein the distal tip
of the piercing element is protectively covered.
[0035] Lockable safety shield assembly 30 in accordance with the
present invention includes user-activatable locking structure. A
feature of the lockable safety shield assembly in accordance with
the present invention is that the locking structure can be
implemented such that it is not "activated" during assembly of the
components, making it easier to assemble the components to syringe
10. Subsequent to assembly of the components, the locking structure
can be "activated", putting the safety shield assembly in a
ready-to-use state.
[0036] Making reference to FIGS. 1-3 and 7-9, shield 42 features at
least one deflectable arm 50. Arm 50 is preferably provided as part
of the structure of the shield. Arm 50, which may be molded as part
of the shield or thereafter created from the shield via various
cutting processes, includes a distal end 54 and a proximal end 52.
Distal end 54 is resiliently affixed to sidewall 46 such as by a
living hinge arrangement, while proximal end 52 is not attached to
the sidewall and is configured for free movement towards an
interior portion of shield 42. In a preferred embodiment, at least
two deflectable arms 50 are provided on shield 42, with these two
arms 50 located on diametrically-opposite sides of shield 42. Arms
50 are thus configured for a free position (FIGS. 1 and 4), wherein
the surface of the arms are substantially co-planar with
circumferential sidewall 46 of the shield, and a locking position
(FIGS. 5, 7, and 8), wherein proximal ends 52 of arms 50 are urged
towards the interior of the shield.
[0037] As best reflected by FIGS. 7 and 8, in a preferred
configuration, proximal ends 52 of the deflectable arms are not
straight. Rather, to best make use of the features of collar 32a
(FIG. 10), proximal ends 52 are preferably canted in a manner such
that when the deflectable arms are positioned towards the interior
of the shield, the proximal ends will be oriented to lockingly
cooperate with distally-facing canted edge 36a of collar 32a, as
will be explained hereinbelow.
[0038] At least one stop member 70 is provided on inside surface 49
of the shield in an area adjacent proximal end 44. In a preferred
embodiment, two stop members 70 are provided, each corresponding to
a respective one of two deflectable arms 50 (see FIG. 9). Stop
member 70 includes a distally-facing stop surface 72. Stop surface
72 is preferably spaced from proximal end 52 of the deflectable arm
a distance "b" as measured along central axis "z" of the shield
(see FIG. 3).
[0039] As best illustrated in FIGS. 7 and 8, in a preferred
configuration, stop surface 72 is preferably not straight. Rather,
to best make use of the features of collar 32a (FIG. 10), stop
surface 72 is preferably canted in a manner such that it will
lockingly cooperate with proximally-facing canted edge 36b of
collar 32a, as will be explained hereinbelow.
[0040] Stop member 70 also includes a proximally-facing sloped
surface 74. Proximally-facing sloped surface 74 facilitates sliding
of shield 42 over collar 32 when the shield is assembled to tube
200. Stop member 70 can be located such that stop surfaces 72 are
circumferentially aligned with respective proximal ends 52 of
deflectable arms 50, when viewed along central axis "Z" of the
shield. Alternately, if desired, stop members 70 can be placed on
interior surface 49 of the shield such that they are
circumferentially offset from respective proximal ends 52 of the
deflectable arms, when viewed along central axis "Z" of the
shield.
[0041] Shield 42 includes structure permitting activation of the
deflectable arms 50 into their locked position (FIGS. 5, 6, 7, 8).
A respective pair of distal and proximal abutments 58, 56 are
provided on deflectable arms 50. Distal abutment 58, which includes
a distally-facing sloped surface 60, is spaced from proximal
abutment 56 by a distance "a" that defines a gap 59. As seen in
FIGS. 3 and 4, in a preferred embodiment where two diametrically
opposite deflectable arms are included, the diametrically opposite
pair of gaps 59 define a diameter "M" slightly greater than
diameter "N" defined by outside surface 48 of she shield when the
arms 50 are in their free position. The effect is that gap 59 is
configured so that it is elevated from the level of surrounding
outside surface 48 of cylindrical sidewall 46 prior to activation
of deflectable arm 50.
[0042] A circumferential ring 80 having an inside wall 82 is
disposed for coaxial movement with circumferential sidewall 46 of
the shield. Inside wall 82 has a diameter "P" at least equal to, if
not greater than, diameter "N" defined by the outside surface of
shield 42. Ring 80 has a width "d" at least equal to, if not
slightly less than, the width of gap 59 as defined by distance "a".
To simplify later assembly, shield 42 is typically configured with
ring 80. Ring 80 can be retained to shield 42, for instance, by a
user-severable connection. That is to say, shield 42 and ring 80
are preferably supplied to the pharmaceutical manufacturer as a
single unit. For example, ring 80 can be supplied by the component
manufacturer such that it is secured to the shield by a
user-severable connection such as a threaded connection.
Preferably, and as is disclosed herein, ring 82 is secured to
distal end 45 of the shield by one or more user-severable
connections 84 configured as thinned, frangible sections of
material between ring 80 and proximal end 45 of the shield, thereby
permitting easy removal of the ring from the shield for further
assembly operations. This type of structure also permits the
component manufacturer to easily form ring 80 and shield 42 as a
single molding.
[0043] Shield 42 further includes structure for retaining shield 42
in the retracted position without being inadvertently
"over-retracted" with respect to syringe 10 and, hence,
inadvertently removed from syringe 10 in the proximal direction. As
seen in FIG. 3, one or more distal stop members 76 can be provided
on interior surface 49 of the shield adjacent distal end 45. Distal
stop members 76 are configured to engage a distally-facing side
portion 36 of the collar to prevent shield 42 from being
over-retracted in a proximal direction. If desired, one or more
tertiary stop members 78 can be provided on shield 42, each spaced
from a respective distal stop member 76 by a distance "c"
approximately equal to thickness "e" of collar 32. Hence, collar 32
can be releasably retained between distal stop members 76 and
tertiary stop members 78 when the shield is in its retracted
position. If desired, tertiary stop member 78 can be provided with
a proximally-facing sloped surface 79 which, like proximally-facing
sloped surface 74 associated with stop members 70, assists in the
assembly of shield 42 about collar 32.
[0044] Operation of a device will now be explained.
[0045] As seen in FIG. 3, means can be fitted to the syringe
adjacent the distal end to provide a barrier to the fluid path
leading to the medicament which will be contained within barrel 16.
The barrier is normally fitted by the syringe manufacturer and
here, can be fitted to the syringe barrel in a process subsequent
to placement of collar 32. If the fluid path is structured as a
luer tip, for instance, a luer tip cap can be fitted. Here, where a
piercing element 26 is configured on the syringe, a well-known
needle shield 29 can be fitted about piercing element 26 so that a
proximal-end of needle shield 29 rests against collar 32. Collar 32
should be configured such that maximum diameter "g" is at least
slightly greater than a maximum diameter "f" displayed by needle
shield 29, such that needle shield 29 will not interfere between
operation of collar 32 and shield 42.
[0046] Preferably, safety shield assembly 30 is preassembled by the
component manufacturer and presented to the pharmaceutical company
in a sterile state, ready to be fit to the syringe once filled with
the drug. Syringe 10 is supplied to the pharmaceutical manufacturer
in a sterile state, ready to be filled with a desired drug and
otherwise processed in a well-known manner. For instance, various
filling operations, particulate inspection operations, labelling
operations, plunger rod assembly operations may be conducted on the
syringe.
[0047] As a first step in assembling the safety shield assembly,
shield 42 is fitted to tube 200. Proximally-facing sloped surfaces
74 and, if provided, 79, assist shield 42 to smoothly surpass edge
34 of the collar. Shield 42 is slid over tube 200 in a proximal
direction, such that collar 32 rests against distal stop members
76. If tertiary stop members 78 are provided, collar 32 will be
releasably retained between distal stop members 76 and tertiary
members 78. After the various filling and processing operations
have been conducted on the syringe, tube 200 is slid over syringe
barrel 16 such that flange 18 of the syringe is captured by lip
structure 210 of the tube. As the shield is held to the tube in a
retracted position, with needle shield 29 affixed to piercing
element 26 will project beyond the distal end 202 of the tube.
Syringe 10, together with lockable safety shield assembly 30, can
be shipped by the pharmaceutical manufacturer to an end-user in a
ready-to-use state.
[0048] FIG. 4 is representative of safety shield 42 of the present
invention mounted about syringe 10 prior to activation of locking
structure, while FIG. 5 is representative of the same construction
after activation of the locking structure. Preferably, a
pharmaceutical manufacturer will ship the prefillable syringe to
the end-user in the state shown in FIG. 5, such that the locking
structure is pre-activated. One way to do this is that the locking
structure may be activated by the component manufacturer, as a
final step in the preassembly of the safety shield assembly 30. For
instance, the step of sliding ring 80 towards gap 59 can be
effected as a final step in an assembly motion during which shield
42 is fitted to tube 200. In this vein, it will also be realized
that because the component manufacturer preferably supplies the
ring and shield to pharmaceutical manufacturer as a preassembled,
single unit, the later assembly operations by the pharmaceutical
manufacturer are simplified, in that the pharmaceutical
manufacturer need only be concerned with sorting, orienting,
distributing and then assembling a single unit about the syringe.
Alternately, of course, it will be realized that the activation
step can be done by by the pharmaceutical manufacturer itself, as
part of the operation in fitting the safety shield assembly to the
syringe.
[0049] Nonetheless, FIG. 5 illustrates activation of the locking
structure, whether by the component manufacturer, by the
pharmaceutical manufacturer or by an end-user. The user-severable
connections 84 connecting ring 80 to distal end 45 of the shield
have been severed, and ring 80 has been slid proximally with
respect to shield 42. Aided by distally-facing sloped surface 60
associated with distal abutment 58, inside surface 82 of the ring
glides along outside surface 48 of the shield, over distally-facing
sloped surface 60, and is secured in gap 59 defined between distal
abutment 58 and proximal abutment 56. Because inside diameter "P"
of ring 80 is smaller than diameter "M" between
diametrically-opposed gaps 59, ring 80 exerts an inwardly-directed
force upon deflectable arms 50. Deflectable arms 50 are thus
deflected about their distal ends 54, such that proximal ends 52
are pushed towards the interior of shield 42. As a deflectable arm
50 is urged inwardly (see particularly FIGS. 7 and 8), proximal end
52 of a given deflectable arm and stop surface 72 of a respective
stop element 70 define a gap 100 between them. Gap 100 is designed
to "capture" collar 32 when the shield is slid distally to cover
piercing element 26. Where the collar has a flat side portion 36,
then gap 100 should have a width "b" at least equal, if not
slightly greater than, thickness "e" of the collar to securely
retain collar 32 in gap 100. If, as depicted in FIG. 10, the collar
is configured with locking tooth 34a, then width "b" should be
chosen so as to accommodate the maximum width "q" associated with
locking tooth 34a, so that locking tooth 34a is securely retained
in gap 100.
[0050] FIG. 6 is representative of shield 42 in its extended
position to protectively cover distal tip 28 of the piercing
element. After needle shield 29 has been removed and an injection
administered in the usual manner, shield 42 is grasped by an
end-user and slid distally with respect to syringe 10. Collar 32,
which is fixed to tube 200, will thus be urged towards proximal end
44 of the shield. Owing to the resiliency of deflectable arms 50,
edge 34 of the collar will push arms 50 in an outward direction
from the interior of the shield and thus will pass along the length
of arms 50. Edge 34 will eventually deflect past proximal end 52,
causing the arm to re-deflect in an inward direction toward the
interior of the shield. An audible indication, such as a clicking
sound, will be heard to indicate activation of the safety
mechanism. Thus, collar 32 will come to rest in gap 100, with the
collar sandwiched between proximal end 52 and stop surface 72.
Collar 32 is thus lockingly held between stop surface 72 and
proximal end 52 of the arm, arresting further movement of the
shield in either proximal or distal directions respective of
syringe 10. Accordingly, shield 42 is retained in its extended
position with respect to piercing element 26, protectively covering
distal tip 28 against inadvertent touch contact.
[0051] As previously explained, in a preferred configuration (FIGS.
7, 8 and 10), deflectable arms 50, stop members 70 and collar 32a
are configured to provide good audible as well as tactile
indication that shield 42 has been locked to collar 32a. As edge 34
of collar 32a clears proximal end 52 of the deflectable arm,
locking tooth 34a enters gap 100. As soon as the locking tooth
enters gap 100, the resilient characteristics of the deflectable
arm cause the arm to re-deflect in an inward direction toward the
interior of the shield. At this moment, an interior portion 49a of
deflectable arm 50 that is located adjacent proximal end 52 is
thrust against shelf 37 of collar 32a. As soon as interior portion
49a is thrust against shelf 37, tactile as well as audible
sensations are transmitted to the user, signaling that shield 42
has been locked to collar 32a. Owing to the canted orientations of
both proximal end 52 of the deflectable arms and stop surface 72 of
the stop members 70, each of the proximal ends 52 and stop surfaces
72 are lockingly retained against their respective distally facing
canted edge 36a and proximally-facing canted edge 36b, such that
tooth 34a is securely locked within gap 100. Thus, by a simple
distal movement, shield 42 is self-locking with collar 34a.
[0052] The various components can be formed from suitable
materials, such as medical-grade plastics or the like. They may be
injection molded in manners well-known to the skilled artisan,
resulting in reliable and cost-effective production of the locking
shield assembly. The locking shield assembly of the present
invention can be adapted with prefillable syringes of various
dimensions and capacities. Various enhancements can be provided to
permit easy assembly. For instance, sections of the sidewall
adjacent the proximal end of the shield can be thinned, or slits
can be incorporated in an area of the shield between the proximal
end of the shield and the proximal edge of the deflectable arms,
all to enhance the easier sliding of the shield proximally over the
collar. Of course, the dimensions for the various components can be
selected such that when the shield is in its retracted position,
the distal tip of the piercing element is exposable for an
injection, and when the shield in its extended position, the distal
tip of the piercing element will be protectively covered to enable
the end user to safely discard the syringe.
[0053] It will be appreciated and understood by those skilled in
the art that further and additional revisions to the invention may
be devised without departing from the spirit and scope of the
appended claims, the invention not being limited to the specific
embodiments shown.
* * * * *