Safety syringe abstract
A safety syringe including a conventional syringe, a locating ring
and an elongate and tubular sleeve wherein the locating ring includes
an outwardly extending projecting tab thereon which extends outwardly
from the distal end of the syringe to engage an elongate slot having
closed distal and proximal ends on the elongate sleeve to allow
the sleeve to be movable between a retracted position wherein a
needle on the syringe is exposed and a pair of extended positions
wherein the needle is enclosed by the sleeve. The sleeve is releasably
retained in one of the extended positions and irreversibly retained
in the other extended position upon rotational movement of the projecting
tab into one or the other of a pair of perpendicular slots on the
sleeve.
Safety syringe claims
What is claimed is:
1. A medical device, comprising
a syringe means having proximal and distal ends and a generally
elongate barrel section extending therebetween,
an elongate and hollow needle having a distal needle point thereon
operatively connected to said distal end of said barrel section,
a locating ring operatively connected to said distal end of said
barrel section and including a body section and an outwardly extending
tab member extending from said body section of said locating ring,
an elongate sleeve member having circumferentially closed proximal
and distal ends, said sleeve member adapted to be longitudinally
movable over said barrel section and said locating ring between
a retracted position wherein said needle point is exposed and an
extended position wherein said sleeve member protects said needle
point,
said sleeve member including an elongate slot having proximal and
distal ends, said elongate slot extending between said proximal
and distal ends of said sleeve member and wherein said tab member
of said locating ring extends therein to slidably retain said sleeve
member about said barrel section and said locating ring, and
a first perpendicular slot located near the proximal end of said
elongate slot and said first perpendicular slot is adapted to receive
said tab member therein and retain said sleeve member in said extended
position wherein said needle point is protected when said sleeve
member is rotated about said barrel section.
2. The medical device of claim 1 wherein said proximal and distal
ends of said elongate slot are adjacent to said proximal and distal
ends of said sleeve member and wherein said first perpendicular
slot includes a locking means associated therewith to retain said
sleeve member in an extended and locked position.
3. The medical device of claim 2 wherein a second perpendicular
slot is located near said proximal end of said elongate slot and
includes a detent extending therein to enable said sleeve member
to be retained in a releasable and extended position by rotating
said sleeve member about said barrel section to move said tab means
into said second perpendicular slot.
4. The medical device of claim 1 wherein a retaining ridge is
operatively associated with said elongate slot to releasably contact
said tab member and retain said sleeve member in said retracted
position.
5. The medical device of claim 4 wherein an expansion channel
is oriented parallel to said elongate slot and adjacent to said
retaining ridge slot to enable said sleeve member to be releasably
movable from said retracted position to said extended position upon
rotation of said sleeve member about said barrel section.
6. The medical device of claim 1 wherein said tab member on said
locating ring may be depressed with respect to said body section
of said locating ring to facilitate the assembly of said sleeve
member and said syringe means.
7. The medical device of claim 6 wherein said tab member is depressed
to a position adjacent to the outer surface of said body section
of said locating ring to allow said tab member to be inserted into
said elongate slot on said sleeve member.
8. A safety syringe, comprising:
a syringe having proximal and distal ends and a generally elongate
barrel section extending therebetween,
an elongate and hollow needle having a distal needle point thereon
operatively connected to said distal end of said barrel section,
a locating ring having a body section and tab means thereon, said
locating ring being operatively connected to said distal end of
said barrel section and wherein said tab means extends radially
outwardly from said body section of said locating ring,
an elongate and tubular sleeve member having proximal and distal
ends, said sleeve member being adapted to be longitudinally movable
over said barrel section and said locating ring between a retracted
position wherein said sleeve member is adjacent to said barrel section
and an extended position wherein said sleeve member protects said
needle point,
an elongate slot longitudinally oriented along said sleeve member,
said slot extending between said proximal and distal ends of said
sleeve member and being adapted to slidably receive said tab means
therein, said elongate slot having a proximal end located distal
to said proximal end of said sleeve member and a distal end located
proximal to said distal end of said sleeve member,
a retaining ridge adapted to extend into said elongate slot near
said distal end thereof to releasably contact said tab means and
retain said sleeve member in said retracted position, and
an expansion slot adjacent to said retaining ridge to enable said
sleeve member to be rotated about said barrel section so that said
tab means slidably passes beyond said retaining ridge as said sleeve
member is moved from said retracted position to said extended position
9. The safety syringe of claim 8 wherein a first perpendicular
slot is located near said proximal end of said elongate slot, said
first perpendicular slot being adapted to receive said tab means
therein when said sleeve member moved to said extended position.
10. The safety syringe of claim 8 wherein first and second perpendicular
slots are located near said proximal end of said elongate slot,
said first and second perpendicular slots being adapted to receive
said tab means therein and wherein said first perpendicular slot
includes a locking means associated therewith to retain said projecting
tab therein and retain said sleeve member in an extended and locked
position wherein said needle point is protected.
11. The safety syringe of claim 10 wherein said second perpendicular
slot includes a detent therein and is located proximal to said first
perpendicular slot along said elongate slot and wherein said second
perpendicular slot is adapted to releasably receive said tab means
therein to retain sleeve member in a releasable and extended position
wherein said needle point is temporarily protected.
12. A safety syringe comprising
a tubular member having proximal and distal ends and a generally
elongate barrel section extending therebetween,
an elongate and hollow needle having a distal needle point thereon
said needle being adapted to be operatively connected to said distal
end of said barrel section,
a cylindrical skirt member extending distally from said distal
end of said barrel section, said skirt member being adapted to receive
a portion of said needle therein,
a locating ring including a body section having an outer surface
and an outwardly extending projecting member extending therefrom,
said locating ring being operatively connected to said skirt member
on said distal end of said barrel section,
an elongate and tubular sleeve member having proximal and distal
ends, said sleeve member being adapted to be longitudinally slidable
over said barrel section and said locating ring between a retracted
position wherein said sleeve member is adjacent to said barrel section
and said locating ring so that said needle point is exposed and
an extended position wherein said sleeve member protects said needle
point,
an elongate slot extending lengthwise along said sleeve member
and including proximal and distal ends positioned near said proximal
and distal ends of said sleeve member and wherein said projecting
member is adjacent to said distal end of said elongate slot when
said sleeve member is in said retracted position and adjacent to
said proximal end of said elongate slot when said sleeve member
is in said extended position, and
a first perpendicular slot located near said proximal end of said
elongate slot and said first perpendicular slots being adapted to
receive said projecting member therein upon rotational movement
of said sleeve member about said barrel section.
13. The safety syringe of claim 12 wherein a retaining ridge projects
inwardly into said elongate slot near said distal end of said elongate
slot and wherein an expansion slot is positioned parallel to said
elongate slot near said retaining ridge to allow said projecting
member to move from said proximal end of said elongate slot to said
distal end of said elongate slot such that said sleeve member is
releasably movable from said retracted position to said extended
position upon rotational movement of said sleeve member about said
barrel section.
14. The safety syringe of claim 12 wherein said first perpendicular
slot is located adjacent said proximal end of said elongate slot
and includes a locking means operatively associated therewith to
retain said projecting member in said first perpendicular slot such
that said sleeve member is longitudinally movable and rotatable
to an extended and locked position wherein said needle point is
protected.
15. The safety syringe of claim 14 wherein a second perpendicular
slot is located along said elongate slot distal to said first perpendicular
slot, said second perpendicular slot includes a detent extending
therein and is adapted to receive said projecting member therein
such that said sleeve member is rotatable to an extended and releasable
position wherein said needle point is protected.
16. A safety syringe comprising
a syringe member having proximal and distal ends, a generally elongate
and tubular barrel section therebetween and a longitudinally slidable
plunger means therein,
an elongate and hollow needle member having a needle hub and a
distal needle point thereon, said needle hub being adapted to be
operatively connected to said distal end of said barrel section,
a cylindrical locating ring having a body section and a radially
outwardly extending projecting tab thereon, said locating ring being
adapted to be fixedly mounted on said distal end of said syringe
member and adjacent said needle hub,
an elongate and tubular sleeve member having proximal and distal
ends thereon, said sleeve member being adapted to be longitudinally
slidable over said barrel section and said locating ring between
a needle point exposing retracted position and first and second
extended positions wherein said needle point is protected,
an elongate and generally rectangularly-shaped slot means extending
lengthwise along said sleeve member, said slot means including a
distal end located proximally of said distal end of said sleeve
member and a proximal end located distally of said proximal end
of said sleeve member wherein said projecting member is movable
between said distal and proximal ends of said slot means as said
sleeve member is moved between said retracted and extended positions,
a generally wedge-shaped retaining ridge extending into said slot
means near the distal end thereof,
an expansion slot oriented generally parallel to said slot means
and adjacent to said retaining ridge wherein said retaining ridge
and said expansion slot cooperate to releasably retain said projecting
tab distally of said retaining ridge when said sleeve member is
in said retraced position,
first and second perpendicular slots operatively located near said
proximal end of said slot means, said first and second perpendicular
slots being oriented generally parallel to each other and adapted
to receive said projecting means therein upon rotational movement
of said sleeve member about said barrel section when said sleeve
member is moved to said first and second extended positions, and
a locking means operatively positioned in one of said first and
second perpendicular slots to irreversibly retain said projecting
means in one of said first and second perpendicular slots when said
sleeve member is in said second extended position.
17. The safety syringe of claim 16 wherein said locking means
is in said first perpendicular slot and wherein said first and second
perpendicular slots are oriented generally perpendicular to said
slot means to receive said projecting means therein upon rotational
movement of said sleeve member about said barrel section and wherein
said sleeve member is releasably retained in said first extended
position upon rotational movement of said projecting means into
said second perpendicular slot.
18. The safety syringe of claim 16 wherein said sleeve member is
releasable from said retracted position upon rotational movement
of said sleeve member about said barrel section.
19. A method of assembling a safety syringe comprising the steps
of
inserting a locating ring having a depressible outwardly extending
projecting means thereon into an elongate and cylindrical sleeve
member by depressing the projecting means until the projecting means
on the locating ring is aligned with an elongate slot having closed
distal and proximal ends on the sleeve member,
releasing the projecting means so that the projecting means is
slidably retained within the distal and proximal ends of the elongate
slot, and
sliding the proximal end of the sleeve member over the distal end
of a syringe barrel until the inner surface of the locating ring
contacts and operationally engages a luer skirt on the distal end
of the syringe barrel.
20. The method of claim 19 wherein a sheathed needle is then attachable
to the distal end of the syringe barrel and wherein the outer surface
of the luer skirt prevents the projecting means from being depressed
once the locating ring engages the luer skirt.
Safety syringe description
FIELD OF THE INVENTION
This invention relates to syringes and more particularly to a safety
type of syringe having a locating ring and a movable protective
sleeve thereon. The present invention relates generally to my copending
patent application entitled "Double Sleeve Safety Syringe"
filed on July 25 1989 assigned Ser. No. 07/385343 which is incorporated
herein by reference and commonly assigned to Sherwood Medical Company.
BACKGROUND OF THE INVENTION
The majority of syringes and needles used today for medical or
laboratory purposes are intended to be discarded after a single
use. Disposal of the syringes and needles poses a potential hazard
for the individuals who use the syringes, as well as for those people
who dispose of them. With the increased awareness concerning the
potential for the transmission of AIDS and other infectious diseases,
a number of different protective devices have been proposed to protect
the user against accidental needle sticks. Protective devices of
this type for use on syringes have become known generally in the
medical field as safety syringes.
A number of safety syringe constructions have been proposed which
satisfy the general requirement that the point of the needle be
enclosed or covered once the syringe has been used. One common feature
of these safety syringes is to provide a protective sleeve which
is movable between a retracted position in which the needle point
is exposed and an extended position in which the needle point is
protected. In many of these safety syringes, the protective sleeve
includes an elongate slot which extends lengthwise along the side
of the protective sleeve and is open at the distal end of the protective
sleeve. Although this type of safety syringe allows the user to
lock the protective sleeve in the extended position, the locking
mechanism may be readily defeated by prying open the distal end
of the protective sleeve to defeat the locking mechanism. Other
safety syringes include protective sleeves having relatively complex
twist-to-lock mechanisms and which do not readily indicate when
the protective sleeve has been locked in the extended position.
In other safety syringes, the protective sleeve locks automatically
when the sleeve is extended. This automatic locking of the protective
sleeve may result in the accidental locking of the protective sleeve
in the extended position prior to the use of the syringe.
Although many of the above described devices meet the general requirements
for a safety syringe, many of the proposed designs are not commercially
viable because they are much too complicated to manufacture economically
and efficiently. Additionally, other devices would require a modification
in the conventional method of using a syringe. This is generally
unacceptable due to the large amount of time and expense involved
in teaching all of the potential users of such a device the proper
technique in using the new device.
Therefore, it is apparent that a need remains for a safety type
of syringe having a protective sleeve which will not interfere with
the conventional method of using the syringe and which may be produced
efficiently and economically.
SUMMARY OF THE PRESENT INVENTION
An object of the present invention is to substantially overcome
the disadvantages mentioned above.
Another object of the present invention is to provide a safety
syringe which performs all of the general requirements of this type
of syringe and which can not be readily manipulated to defeat the
locking mechanism once the protective sleeve is placed in a readily
observable locked and extended position.
A further object of the present invention is to provide a safety
syringe which includes a protective sleeve which is movable between
a releasable extended position and a locked and extended position.
The present invention consists generally of a locating ring mounted
on the distal end of a conventional syringe which cooperates with
a protective sleeve slidably positioned along the outer surface
of the syringe barrel. The protective sleeve is initially maintained
in a releasable retracted position wherein the protective sleeve
is adjacent to the syringe barrel and the needle point is exposed.
From the retracted position, the protective sleeve is slidable to
a pair of extended positions wherein the protective sleeve extends
beyond the distal needle point to protect the user from accidental
contact with the needle point.
The locating ring of the present invention includes an outwardly
directed projecting tab member which extends outwardly from the
locating ring and is adapted to be received in an elongate slot
located along the side of the protective sleeve. The elongate slot
extends between the closed proximal end and the closed distal end
of the protective sleeve. A retaining lip is positioned along the
elongate slot to extend inwardly into the elongate slot and releasably
retain the tab member near the distal end of the elongate slot when
the protective sleeve is moved to the retracted position.
A pair of perpendicularly oriented slots are located near the proximal
end of the elongated slot. The first perpendicular slot is located
proximal to the second perpendicular slot along the elongate slot
and includes a locking lip therein to irreversibly retain the protective
sleeve in an extended and locked position once the syringe has been
used. The second perpendicular slot includes a detent therein to
temporarily retain the protective sleeve in a releasable extended
position which temporarily protects the needle point. The releasable
extended position is particularly useful in situations where the
syringe is filled with medication at one location and then transported
to a second location where the medication is dispensed form the
syringe. The releasable extended position provides the user with
needed protection against accidental contact with the needle point
during the transport of the medication-containing syringe and allows
the user to return the protective sleeve to the retracted position
to dispense the medication from the syringe.
An advantage of the present invention is that the safety syringe
is simple to operate and allows the user to slide the protective
sleeve between a releasable retracted position and a pair of extended
positions.
A further advantage of the present invention is that the distal
end of the protective sleeve is closed to prevent the protective
sleeve from being pried open and returned to the retracted position.
Yet another advantage of the present invention is that the protective
sleeve is rotatable to a temporary or releasable extended position
wherein the protective sleeve is retained in the extended position
until the protective sleeve is rotated to move the tab member from
the second perpendicular slot.
Yet another advantage of the present invention is that the protective
sleeve is initially movable to a releasable retracted position wherein
the protective sleeve is retained substantially adjacent to the
barrel of the syringe so that the safety syringe may be used in
a conventional manner.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevated perspective view of the present invention
with the protective sleeve in the retracted position;
FIG. 2 is an elevated perspective view of the present invention
with the protective sleeve in the extended and locked position;
FIG. 3 is an elevated perspective view of the locating ring of
the present invention;
FIG. 4 is an elevated side view of the present invention showing
the protective sleeve and locating ring in the partially assembled
condition;
FIG. 5 is a side view partially in cross-section of the present
invention taken generally along lines 5--5 of FIG. 1; and
FIG. 6 is a cross-sectional view of the present invention taken
generally along lines 6--6 of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As described herein, the present invention is intended to be used
in conjunction with a conventional syringe; however, the protective
sleeve and locating ring of the present invention are readily adaptable
for use on nearly any medical or laboratory device having an elongate
barrel section and a needle. For example, the present invention
may be adapted for use on commonly available medical devices preferably
having a luer lock or other projection on the distal end thereof.
Accordingly, as used herein, the term "syringe" is intended
to broadly include or encompass nearly any medical or scientific
device having a needle extending therefrom wherein it is desired
to protect a user from accidental contact with the needle point.
In describing the present invention, the term "distal end"
is used herein to refer to the end of the part closest to the normally
exposed needle point. The term "proximal end" is used
herein to refer to the end of the part farthest from the normally
exposed needle point. The term "retracted position" is
used herein to refer to the relative position of the protective
sleeve about the syringe barrel wherein the proximal end of the
protective sleeve is adjacent to the proximal end of the syringe
barrel and the distal needle point is exposed. The term "extended
position" is used herein to refer to the relative position
of the protective sleeve wherein the proximal end of the protective
sleeve is adjacent to the distal end of the syringe barrel and the
distal end of the protective sleeve extends beyond the distal needle
point.
The present invention is described herein with particular reference
to a conventional syringe having an elongate and tubular syringe
barrel section 10 with a proximally located finger flange 11; a
plunger member 12 which is slidable within the barrel section 10
and an elongate and hollow needle assembly 13 through which the
contents of the barrel section 10 are dispensed when the plunger
member 12 is moved distally in the barrel section 10. The needle
assembly 13 includes an elongate and holloW needle 14 having a sharpened
needle point 15 at the distal end thereof and an enlarged hub member
16 at the proximal end of the needle assembly 13.
A conically-shaped luer tip 17 and a cylindrically-shaped luer
lock skirt 18 are integrally formed on the distal end of the barrel
section 10 and are arranged thereon such that the luer lock skirt
18 is spaced apart from and encircles the luer tip 17. The interior
surface of the luer lock skirt 18 preferably includes internally
oriented threads which are adapted to threadedly engage complimentary
ridges on the proximal end of the needle hub 16 to releasably retain
the needle assembly 13 in fluid-tight communication with the distal
end of the barrel section 10. The exterior surface of the luer lock
skirt 18 is generally cylindrical and extends parallel to the longitudinal
axis of the barrel section 10.
As illustrated in the drawings, the preferred embodiment of the
present invention consists generally of a cylindrical locating ring
20 which is fixedly attached to the luer lock skirt 18 on the distal
end of the barrel section 10 and an elongate and tubular protective
sleeve 40 which is slidably movable over the locating ring 20 and
the barrel section 10. The locating ring 20 of the present invention
is preferably constructed of a rigid plastic such as a polycarbonate
and is press-fit or fused to the external surface of the luer lock
skirt 18. The protective sleeve 40 slidably fits over the syringe
barrel 10 and locating ring 20 and is movable between retracted
and extended positions as described hereinafter.
As illustrated in FIG. 5 the internal diameter of the locating
ring 20 is approximately equal to the external diameter of the luer
lock skirt 18 and preferably includes an inwardly directed retaining
ridge 22 adjacent to the internal surface of the proximal end of
the locating ring 20. The retaining ridge 22 is adapted to engage
and fixedly retain the locating ring 20 on the luer lock skirt 18
adjacent to the distal end of the barrel section 10. The external
surface of the locating ring 20 generally includes a circumferential
body section 28 and an outwardly directed projecting tab member
24. The tab member 24 extends outwardly from the proximal side of
the body section 28 a sufficient distance to cooperate with an elongate
slot 42 which extends longitudinally along one side of the protective
sleeve 40 as described hereinafter. As best illustrated in FIG.
3 the tab member 24 is generally bordered by a slot 26 which allows
the tab member 24 to be depressed with respect to the body section
28 of the locating ring 20 during the assembly of the safety syringe
of the present invention as described hereinafter. Once the syringe
of the present invention is assembled, the tab member 24 is prevented
from being depressed by contact between the external surface of
the luer lock skirt 18 and the internal surface of the tab member
24.
The protective sleeve 40 of the present invention is a generally
elongate and tubular sleeve member which is preferably constructed
of a semi-rigid plastic such as polypropylene. One side of the protective
sleeve 40 includes the elongate slot 42 extending longitudinally
between the proximal and distal ends thereof. An outwardly extending
circumferential flange member 44 is located on the distal end of
the protective sleeve 40. A pair of outwardly directed wing-shaped
finger flanges 46 extend outwardly from the protective sleeve 40.
The finger flanges 46 are oriented perpendicular to the longitudinal
dimension of the protective sleeve 40 near the proximal end of the
protective sleeve 40. The flange member 44 and the finger flanges
46 enable the user to safely and conveniently slide and rotate the
protective sleeve 40 about the barrel section 10 of the syringe
between the retracted and extended positions as described hereinafter.
The elongate slot 42 of the present invention preferably includes
distal and proximal ends and extends lengthwise along the side of
the protective sleeve 40 to a position adjacent to the distal and
proximal ends of the protective sleeve 40. A wedge-shaped retaining
lip 50 projects inwardly into the elongate slot 42 near the distal
end of the elongate slot 42 to retain the tab member 24 distally
of the retaining lip 50 in the elongate slot 42 when the protective
sleeve 40 is in the retracted position as described hereinafter.
The protective sleeve 40 also includes an expansion channel 52 which
is oriented parallel to the elongate slot 42 near the distal end
thereof and adjacent to the retaining lip 50 to enable the tab member
24 to be releasably moved beyond the retaining lip 50 to allow the
protective sleeve 40 to be moved from the retracted position to
one of the extended positions as described more fully hereinafter.
As illustrated in FIG. 4 first and second perpendicular slots,
56 and 54 respectively, are located near the proximal end of the
elongate slot 42 to selectively retain the tab member 24 therein
when the protective sleeve 40 is moved to one of the extended positions
as described hereinafter. The first perpendicular slot 56 is oriented
perpendicular to the elongate slot 42 and consists of a generally
rectangularly-shaped opening in the protective sleeve 40 which is
located adjacent to the proximal end of the elongate slot 42. The
first perpendicular slot 56 includes an inwardly projecting and
wedge-shaped locking ridge 58 which preferably projects from the
distal side of the first perpendicular slot 56 into the first perpendicular
slot 56 to enable the user to move the protective sleeve 40 to a
locked and extended position by initially pushing the protective
sleeve 40 distally until the tab member 24 is adjacent to the first
perpendicular slot 56 and then rotating the protective sleeve 40
counterclockwise about the barrel section 10 until the tab member
24 is permanently received in the first perpendicular slot 56. The
second perpendicular slot 54 is located distally to the first perpendicular
slot 56 along the elongate slot 42 and consists of a generally rectangularly-shaped
opening in the protective sleeve 40 having a detent 55 which extends
inwardly from the proximal side of the second perpendicular slot
54 adjacent to the elongate slot 42. The second perpendicular slot
54 is oriented perpendicular to the elongate slot 42 to enable the
user to move the protective sleeve 40 to a releasable and extended
position by initially pushing the protective sleeve 40 distally
until the tab member 24 is adjacent to the second perpendicular
slot 54 and then rotating the protective sleeve 40 counterclockwise
about the barrel section 10 until the tab member 24 is received
in the second perpendicular slot 56.
It should be understood that although the first perpendicular slot
56 and the second perpendicular slot 54 are described and illustrated
herein as being positioned on the same side of the elongate slot
42 and adjacent to one another, it is anticipated that their relative
positions or shape may be modified without departing from the scope
of the present invention. For example, it is anticipated that the
first perpendicular slot 56 and the second perpendicular slot 54
may be located on opposite sides of the elongate slot 42 so that
rotation of the protective sleeve 40 in one direction will move
the tab member 24 into the first perpendicular slot 56 and rotation
of the protective sleeve 40 in the other direction will move the
tab member 24 into the second perpendicular slot 54.
The present invention is assembled by depressing the tab member
24 on the locating ring 20 until the external surface of the tab
member 24 adjacent to body section 28 of the locating ring 20 and
then sliding the locating ring 20 through the distal end of the
protective sleeve 40 so that the tab member 24 is aligned with the
elongate slot 42. A conventional syringe, as described above, is
then attached to the assembled locating ring 20 and protective sleeve
40 (FIG. 4) by sliding the syringe through the proximal end of the
protective sleeve 40 until the retaining ridge 22 on the internal
surface of the locating ring 20 engages and partially deforms the
external surface of the luer lock skirt 18 on the distal end of
the barrel section 10. The contact between the internal surface
of the locating ring 20 and the external surface of the luer lock
skirt 18 prevents the tab member 24 from being depressed once the
locating ring 20 has been placed on the luer lock skirt 18 so that
the tab member 24 is retained within the elongate slot 42 of the
protective sleeve 40 and cannot be removed therefrom unless excessive
force is used to disassemble the present invention.
Once the safety syringe of the present invention is assembled,
the user may move protective sleeve 40 proximally along the barrel
section 10 to a retracted position wherein the distal end of the
protective sleeve 40 is adjacent to the distal end of the luer tip
17. The needle assembly 13 may then be attached to the present invention
in a conventional manner by grasping the finger flanges 46 on the
protective sleeve 40 and then threadedly engaging the complementary
ridges on the needle hub 16 with the internal threads on the luer
lock skirt 18. As illustrated in FIG. 1 when the protective sleeve
40 is in the retracted position, the needle point 15 and nearly
the entire length of the shaft of the hollow needle 14 extend distally
beyond the distal end of the protective sleeve 40 and medication
may be drawn into the present invention in a conventional manner.
The protective sleeve 40 is releasably held in the retracted position
by contact between the tab member 24 and the inwardly directed retaining
lip 50 in the elongate slot 42. The retaining lip 50 cooperates
with the tab member 24 to prevent the protective sleeve 40 from
moving distally along the barrel section 10. Additionally, the longitudinal
orientation of the elongate slot 42 enables the user to attach the
needle assembly 13 to the luer tip 17 while grasping only the finger
flanges 46 of the protective sleeve 40 because the engagement between
the tab member 24 and the elongate slot 42 and the engagement between
the locating ring 20 and the luer lock skirt 18 prevents rotation
of the protective sleeve 40 about the barrel section 10.
In order for the user to move the protective sleeve 40 from the
retracted position to one of the extended positions, the user must
grasp the finger flanges 46 along the proximal end of the protective
sleeve 40 and slightly rotate the protective sleeve 40 clockwise
about the syringe barrel 10. This clockwise rotation of the protective
sleeve 40 about the barrel section 10 causes the tab member 24 to
press against the side of the elongate slot 42 adjacent to the expansion
channel 52 and compress the expansion channel 52. Compression of
the expansion channel 52 enables the tab member 24 to pass beyond
the retaining lip 50 as the user pushes the protective sleeve 40
distally along the barrel section 10. Further distal movement of
the protective sleeve 40 along the barrel section 10 allows the
protective sleeve 40 to be moved to one of the extended positions
wherein the shaft of the needle 14 and the needle point 15 are protected
by the protective sleeve 40 and tab member 24 is moved adjacent
to either the first or second perpendicular slot, 56 or 54 respectively,
near the proximal end of the elongate slot 42.
As the protective sleeve 40 is released from the retracted position
and moved distally along the barrel section 10 the protective sleeve
40 may be moved to an initial releasable and extended position The
user may move the protective sleeve 40 to the releasable and extended
position by moving the protective sleeve 40 distally along the syringe
barrel 10 until the tab member 24 is adjacent to the second perpendicular
slot 54. The protective sleeve may then be rotated counterclockwise
by grasping the finger flanges 46 and rotating the protective sleeve
40 about the barrel section 10 to cause the tab member 24 to pass
beyond the detent 55 and enter the second perpendicular slot 54.
In this position, the protective sleeve cannot be retracted unless
the protective sleeve 40 is rotated clockwise about the barrel section
10 to move the tab member 24 past the detent 55 and into the elongate
slot 42.
Once the tab member 24 is removed from the second perpendicular
slot 54 the protective sleeve 40 may be moved proximally along
the barrel section 10 and returned to the retracted position so
that the user may administer the medication contained therein in
a conventional manner. Once the injection has been given, the protective
sleeve 40 may be moved to a locked and extended position (FIG. 2)
by moving the protective sleeve 40 distally along the barrel section
10 until the tab member 24 contacts the proximal end of the elongate
slot 42. The user may then rotate the protective sleeve 40 counterclockwise
about the barrel section 10 so that the tab member 24 enters the
first perpendicular slot 56. The rotation of the protective sleeve
40 about the barrel section 10 causes the tab member 24 to pass
beyond the locking lip 58 of the first perpendicular slot 56 so
that the protective sleeve 40 is in an extended and locked position.
Once this occurs, the protective sleeve 40 can no longer be rotated
or moved about the barrel section 10 unless extraordinary force
is used to force the tab member 24 beyond the locking lip 58 of
the first perpendicular slot 56 and into the elongate slot 42.
The foregoing description of the preferred embodiment is intended
to be illustrative of one form of the invention and may be modified
without departing from the scope of the present invention which
is defined by the claims attached hereto. |