 |
Description  |
|
|
BACKGROUND OF THE INVENTION
This invention relates generally to hypodermic needles and catheters which
are adapted to inject substances into humans, animals, and/or to withdraw
specimens therefrom. More particularly, the present invention relates
generally to protective devices which are employed for shielding the
needle of a hypodermic syringe, catheter or other injecting or withdrawing
device after usage thereof.
The vast majority of hypodermic needles are disposable type needles which
are discarded after usage. The shielding of the sharp end of the
hypodermic needle is of critical concern to health practitioners both in
relation to needle disposal and to handling the needle. Accidental
exposure to the sharp end of the needle can have very serious and even
fatal health consequences. For example, the needle may be contaminated
with diseases such as hepatitis and AIDS. It is well documented that
accidental puncture with a contaminated needle could result in infection
with such diseases. Because the hypodermic needle is frequently used
during times of emergency or high stress, it is highly desirable that the
needle be immediately shielded after usage in a reliable and efficient
manner which provides a high degree of protection from accidental
puncture.
A wide variety of different types of devices for shielding a hypodermic
needle against inadvertent needle exposure have been advanced. Protective
cap-like members for enclosing the sharp end of the needle are
incorporated into a number of shield devices. Mitchell U.S. Pat. No.
4,631,057 discloses a shielded needle wherein a needle guard is mounted on
the body of a hypodermic syringe. The needle guard moves from the
retracted position at which the needle is exposed for usage to an extended
position at which the guard shields the needle. The needle guard can be
locked in the extended position by inter-locking members carried by the
needle guard and a collar which is mounted on the body of the syringe.
Sampson et al U.S. Pat. No. 4,573,976 discloses a shielded needle wherein a
needle guard is mounted on the body of the syringe. In an extended
position, the needle guard obstructs access to the point of the needle. In
a retracted guard position, the point of the needle is exposed for usage.
The guard may be releasably retained in a retracted position. Interlocking
members on the syringe body are responsive to generally axial movement of
the guard to the extended position to prevent reverse movement of the
guard toward the retracted position.
In U.S. patent application Ser. No. 093,750, filed on Sept. 8, 1987,
entitled "Protective Sheath for Hypodermic Needle", a new and improved
protective needle sheath for a hypodermic needle comprises a protective
shield assembly which is suitably mounted to the base of the hypodermic
needle for shielding the needle point in an extended axial position. The
protective shield assembly is axially spaced from the needle point in the
retracted position to permit exposure of the needle. In one embodiment,
the shield assembly comprises a pair of telescopic concentric, generally
cylindrical shields. A mounting flange projects transversely from the
needle base. The inner shield has a generally cylindrical surface which
axially slides across the peripheral edge of the mounting flange. The
sleeve has an end-wall portion and an interior locking means engagable
with the flange to lock the inner shield in a fixed axial position wherein
the shield encloses a portion of the needle. A radially projecting lock
ring is positioned at the opposite distal end of the inner shield. The
outer shield has a generally cylindrical surface which axially slides
across the peripheral edge of the ring. At a proximal end of the second
shield, an interior locking means is engagable with the lock ring to lock
the outer shield in fixed axial position with the inner shield whereby the
outer shield encloses the needle point and a portion of the needle. In one
disclosed embodiment, a flap extends interiorily to the protective guide
sleeve. The flap slides along the needle and obstructs axial access to the
sharpened needle point in the extended position of the protective shield.
In U.S. application No. 140,566, filed on Jan. 4, 1988, and entitled
"Corrugated Protective Sheath for Hypodermic Needle", a protective sheath
is mounted to the base of the needle. The protective sheath has a flexible
corrugated form which is expandable from a retracted, folded configuration
to an extended expanded configuration for shielding the needle point. One
end of the protective sheath is anchored in a fixed relationship with the
base of the needle. A flap-like member extends interiorily at the opposing
leading portion of the shield. In the extended position, the flap
cooperates with the sheath to obstruct access to the sharpened needle
point to thereby prevent inadvertent puncture.
SUMMARY OF THE INVENTION
Briefly stated, one embodiment of the invention is in the form of a
protective hypodermic needle cover assembly for a needle having a base and
terminating in a sharpened point. A guide member transversely projects
from the needle base and defines a pair of diametrically-spaced slots. A
protective shield comprising a cap-like member defining a needle opening
is adapted for protectively shielding the needle point in an extended
protective position. The needle extends through the opening to expose the
needle point in the retracted position. A pair of guide rods extend from
the protective cap-like member. The guide rods are received in the slots
so that the rods move through the slots when the protective shield member
is displaced from the retracted to protective positions with the rods
connecting the protective shield to the hypodermic needle in the
protective position. A protective flap extends from the cap-like member
and is interposed between the opening and the needle in the extended
protective position. The rods may interact with the guide member to spring
load the cap-like member for maintaining the protected position.
Serrations project from the rods and interact with the guide member to
prevent retraction of the cap-like member. Stops are connected to the rods
to limit the travel of the rods through the slots.
In another embodiment of the invention, a protective foldable sheath is
mounted to the needle. A protected cover at the distal end of the sheath
defines a needle opening. A guide member projects diametrally from the
needle mounting base to define a pair of diametrically-spaced slots. Guide
rods having serrations are mounted to the sheath cover and are slidably
receivable in the slots for unidirectionally guiding the sheath to the
protective mode.
In a third embodiment of the invention, an extendable shield means
comprises a plurality of telescopic shield sections. One of the shield
sections forms an enclosure having an exteriorly disposed peripheral
groove. Another of the shield sections forms an enclosure which is
dimensioned to enclose the first shield section and is axially slidable
along the first shield section to enclose the sharpened needle point in an
extended axial position. The second shield section further comprises a
radial projection which is engagable in the groove to lock the shields in
the extended position. Diametral tabs extend from the outer most shield
section to facilitate moving the cover to the protective mode.
An object of the invention is to provide a new and improved protective
cover for a hypodermic needle.
Another object of the invention is to provide a new and improved protective
cover of efficient construction which can be easily, manually expanded
from a folded retractable position to an expanded, extended protective
mode after needle usage for obstructing access to the sharpened end of a
hypodermic needle.
Another object of the invention is to provide a new and improved protective
cover of inexpensive construction which is relatively easy to manufacture
and to assemble on a hypodermic needle.
A further object of the invention is to provide a new and improved
protective cover assembly which is easily positionable to lock a
protective needle cover in the protective position.
Other objects and advantages of the invention will become apparent from the
drawing and the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view, partly in phantom, of a hypodermic
syringe and a protective cover assembly of the present invention, said
cover assembly being positioned in a retracted mode wherein the syringe
needle is exposed;
FIG. 2 is an enlarged fragmentary, side elevational view, partly in section
and partly broken away, of the hypodermic syringe and the protective cover
assembly of FIG. 1;
FIG. 3 is an enlarged fragmentary, side elevational view, partly in
section, of the hypodermic syringe and the protective cover assembly of
FIG. 1, said cover assembly being positioned in a protective mode;
FIG. 4 is a cross-sectional view of the hypodermic syringe and protective
cover assembly of FIG. 3 taken along the line 4--4 thereof;
FIG. 5 is a fragmentary, side elevational view, partly in section, of a
hypodermic syringe and a second embodiment of a protective cover assembly
in accordance with the present invention, said cover assembly being
positioned in a retracted mode wherein the syringe needle is exposed;
FIG. 6 is a side elevational view, partly in section, of the hypodermic
syringe and protective cover assembly of FIG. 5, said cover assembly being
positioned in the protective mode;
FIG. 7 is a cross-sectional view of the hypodermic syringe and protective
cover assembly of FIG. 5 taken along the line 7--7 thereof;
FIG. 8 is a fragmentary side elevational view, partly in section and partly
broken away, of a hypodermic syringe and a third embodiment of protective
cover assembly in accordance with the present invention, said cover
assembly being positioned in a retracted mode wherein the syringe needle
is exposed; and
FIG. 9 is a fragmentary side elevational view, partly broken away, partly
in section, and partly in phantom, of the hypodermic syringe and
protective cover assembly of FIG. 8, the cover assembly being positioned
in a protective mode.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the drawings wherein like numerals represent like parts
throughout the Figures, a hypodermic syringe is designated generally by
the numeral 10 in FIG. 1. Except for the modifications described herein,
syringe 10 has a generally conventional form and function. The hypodermic
syringe 10 mounts a protective cover assembly 12 in accordance with the
present invention. Syringe 10 generally comprises a main syringe body 14
and a hypodermic needle 16. The protective cover assembly 12 is adapted
for protecting the distal sharpened end of the syringe hypodermic needle
16 after usage of the syringe. The protective cover assembly 12 has
applicability for syringes, catheters and like devices which are employed
for injecting substances and/or drawing specimens. Accordingly, the
specific illustrated embodiments of syringe 10 and hypodermic needle 16
with which the invention is illustrated and described may have numerous
embodiments and configurations.
The main syringe body 14 includes a generally cylindrical barrel or vial 20
which receives the substance injected by the syringe and/or the specimen
withdrawn by the syringe. The vial 20 constitutes the principal body
portion of the syringe. A needle socket 22 or anchoring head is formed at
one end of the syringe body for receiving and mounting the hypodermic
needle 16.
The hypodermic needle 16 includes an integral upper mounting base 24 which
tapers into a cannula-like head having a distal sharpened point 26. A
mounting base 24 fixedly mounts or is anchored by the socket 22 of the
syringe body. The cannula defines an axial fluid passageway which extends
from the vial through the needle and opens through the sharpened point end
in a conventional manner.
A wide variety of means for fixing or mounting the base 24 of the
hypodermic needle to the mounting body of the syringe or other device may
be provided. The hypodermic needle 16 may be mounted at the syringe body
by a molding process wherein the socket or anchoring is integrally formed
around the needle base. Alternatively, a Luer-type connector (not
illustrated) may connect the mounting base with the main syringe body.
With reference to FIGS. 1 through 4, the protective cover assembly 12
comprises a cap 30 having an interiorly projecting, integral protective
flap 32 and a central axial aperture 34. The aperture 34 is adapted and
dimensioned so that the needle extends therethrough in the retracted mode
illustrated in FIGS. 1 and 2. A circumferential annular anchoring collar
36 extends outwardly (generally radially) at the proximal end of the cap.
The cap 30 is preferably composed plastic or other inexpensive molded
material. The cap 30 is dimensioned to partially enclose a portion of the
needle base 24.
A slotted wing 40 extends diametrically of the needle base. The wing 40
defines a pair of diametrically-spaced apertures 42 and 44. Guide rods 46
and 48 are fixed at diametrically located positions of the collar 36 and
extend through the apertures 42 and 44. The guide rods 46 and 48 function
to guide the cap 30 to the protective position and to retain the cap to
the syringe. In addition, the guide rods may have sufficient resilience so
that the rods are spring loaded against the wing 40 to thereby maintain
the protective position illustrated in FIG. 3. The guide rods may also
have a series of longitudinally spaced serrations 52 which are engageable
against aperture-defining portions of the wings to prevent the cap from
being redisplaced to the retracted position. The apertures 42 and 44 and
the serrations 52 are dimensioned to allow generally unidirectional
movement to the extended protective position. A pair of knobs 49 having
diameters greater than the corresponding diameters of the apertures 42 and
44 function as stops to limit the axial travel of the guide rods through
the apertures.
As best illustrated in FIG. 2 at the retracted position wherein the
hypodermic needle is exposed, the protective flap 32 is bent against the
distal portion of the needle base 24. When the protective cap 30 is
manually moved to the protective position illustrated in FIG. 3, the flap
32 resiliently slidably engages along the needle 16 until the flap clears
the needle point 26 at the extended position of FIG. 3. The flap 32
springs to an extended configuration for inter-positioning between the
aperture 30 of the cap and the needle point 26, thus providing a secondary
needle shield. The guide rods 46 and 48 are spring biased and the
serrations 52 engage against opposing aperture defining portions of the
wing 40 to spring load the cap at the protective position.
With reference to FIGS. 5 through 7, a second embodiment of a protective
cap assembly is generally designated by the numral 60. Cap assembly 60
comprises three telescoping shield sections 62, 64, and 66, which in a
compact retracted nested configuration of FIG. 5, allow the needle 16 to
be exposed for usage. The sections 62, 64 and 66 may have a Wide variety
of shapes. The sections preferably have a semi-rigid resilient structure
and may be formed from plastic or similar materials. Section 62 is
anchored or connected to the needle base 24. Each of the sections have
distal end panels which define respective central apertures 63, 65 and 67.
The needle extends through the apertures 63, 65 and 67 in the retracted
positions. The needle also extends through apertures 63 and 65 in the
expanded protective position as illustrated in FIG. 6.
Sections 62 and 64 have peripheral circumferentially extending locking
grooves 71 and 73, respectively, proximate the distal exterior ends of the
sections. Each of the sections 64 and 66 have corresponding interiorily
projecting tongues 72 and 74, respectively, which are receivable in the
locking grooves 71 and 73, respectively, to secure the shield sections in
the protective expanded position of FIG. 6. The sections have sufficient
resiliency so that the tongues slide along the exterior surface of a
corresponding interiorly adjacent section 68 and snap into the grooves at
the extreme protective position.
The outer shield section 66 which essentially encloses the sharpened needle
point 26 also includes an integral protective flap 68 which rides along
the needle 16 and is interposed between the aperture 67 and the sharpened
needle point 26 in the protective mode in a manner similar to that
described in relation to flap 32. In addition, the outer section 66 has a
pair of diametral integral wing-like tabs 80 and 82 which facilitate the
transformation of the shield to the telescoping protective mode.
With additional reference to FIGS. 8 and 9, a third embodiment of a
protective cover assembly is generally designated with the numeral 90.
Protective cover assembly 90 includes a corrugated sheath 92 and an end
plate 94 which is mounted at the distal end of the corrugated sheath. The
diameter of the end plate 94 is greater than the diameter of the sheath
92. The end plate 94 defines a central aperture 95 through which the
needle extends in the retracted position. A pair of guide rods 96 and 98
are anchored at outer diametral positions of the end plate 94. An integral
protective flap 100 also extends interiorily from the end plate 94. Flap
100 is similar in form and function to previously described flaps 32 and
68. It will be appreciated that the end plate 94 functions as the primary
needle shield and the flap 100 functions as a secondary or auxiliary
needle shield. Flap 100 resiliently slidably engages along the needle 16
for inter-positioning between the end of the end plate aperture 95 and the
sharpened needle point 26 as best illustrated in FIG. 9.
A guide bar 102 is fastened to the needle base and extends radially
therefrom. The guide bar defines a pair of diametrically-spaced slots or
apertures 104 and 106 which receive the guide rods 96 and 98. The guide
rods include a series of longitudinally spaced serrations 99 which
function in a manner similar to serrations 52 to form a one way stop for
maintaining the protective cover in the extended protective mode. A pair
of knobs 108 are mounted at the end of the guide rods to limit the travel
of the end plate 94 relative to the needle base. Th guide rods may also
function to spring bias the protective cover in the protective mode as
best illustrated in FIG. 9.
While preferred embodiments of the foregoing invention have been set forth
for purposes of illustration, the foregoing description should not be
deemed a limitation of the invention herein. Accordingly, various
modifications, adaptations, and alternatives may occur to one skilled in
the art without departing from the spirit and the scope of the present
invention.
* * * * *
|
|
 |
|
 |
Description |
|
