Safety syringe abstract
The present invention relates to a disposable safety syringe constructed
such that the attached needle may be disposed of safely after use,
and additionally configured so that all fluid is forced from the
barrel of the syringe, and further constructed so that the plunger
may not be fully removed from the barrel, preventing the inadvertent
loss of fluid that has been drawn into the syringe barrel.
Safety syringe claims
What is claimed is:
1. A disposable safety syringe, which leaves no residual injection,
comprising: (a) a syringe barrel, which comprises a connecting tip
for a needle base at an upper end of the syringe barrel; a barrel
finger flange; a rear cap receptacle for maintaining sterility at
a lower end of the syringe barrel; and a plunger stopping protrusion
which is slanted toward the upper end of the syringe barrel around
the inner diameter of the lower end of the syringe barrel; (b) a
needle base connected to the connecting tip of the syringe barrel,
wherein said needle base comprises a syringe needle connected to
an upper end of the needle base; and a needle base protrusion at
a lower end of the needle base; (c) a syringe plunger, which comprises
an injection tip connected at an upper end of the plunger; a syringe
thumb rest at a lower end of the plunger; an injection tip protrusion
at an upper end of the injection tip; and a plunger stopping rib
for contacting the plunger stopping protrusion to prevent loss of
injection; and (d) a needle shield, placed outside of the syringe
barrel, which comprises a disposable cap receptacle, and a detachment
handle at an upper end of the needle shield.
2. The disposable safety syringe of claim 1 further comprising
a rear cap for maintaining sterility connected to the rear cap receptacle.
3. The disposable safety syringe of claim 1 further comprising
a disposable cap connected to the disposable cap receptacle.
4. The disposable safety syringe of claim 1 further comprising
a protective cap connected to the needle base.
5. The disposable safety syringe of claim 2 further comprising
multiple of sterility rings around an inside diameter of the rear
cap.
6. The disposable safety syringe of claim 1 wherein the needle
shield further comprises a thread for connecting the needle shield
to the needle base; a slanted protrusion capable of passing over
the needle base protrusion; and a catching ledge for catching the
needle base protrusion and impeding its movement.
7. The disposable safety syringe of claim 4 further comprising
multiple sterility rings around an inside diameter of the protective
cap.
8. A disposable safety syringe comprising: (a) a syringe barrel
having a tapered first end connectable to a needle base, and a second
end; (b) a plunger within the syringe barrel having an injection
tip protrusion capable of advancing into and forcing fluid out of
the tapered end of the syringe barrel; (c) a rear cap receptacle
on the second end of the syringe barrel capable of receiving a rear
cap; (d) a needle connected to the needle base; and (e) a movable
needle shield surrounding the syringe barrel, wherein the movable
needle shield exposes the needle in a first position, and covers
the needle in a second position.
9. The syringe of claim 8 wherein the tapered end defines a space
and wherein the injection tip protrusion is capable of completely
filling the space to force all of the liquid out of the tapered
end.
10. The syringe of claim 8 further comprising a rear cap, wherein
the rear cap contains at least one sterility ring for contacting
a portion of the rear cap receptacle.
11. The syringe of claim 8 wherein the second end of the syringe
barrel has on its interior at least one plunger stopping protrusion,
wherein at least one of the plunger stopping protrusions is capable
of contacting a portion of the plunger to prevent its removal from
the syringe barrel.
12. The syringe of claim 8 wherein the needle shield further comprises
a disposal cap receptacle capable of receiving a disposal cap when
in the second position.
13. A disposable safety syringe, comprising: (a) a syringe barrel,
having first and second ends; (b) a needle base connected to the
first end of the syringe barrel, said needle base having a needle
and one or more needle base protrusions; (c) a movable needle shield
surrounding the exterior of the syringe barrel, wherein the needle
shield has a thread at a first end and exposes the needle in a first
position, wherein the movable needle shield is locked in the first
position when the needle base protrusions and the movable needle
shield thread are fixed in a screw relationship, and covers the
needle in a second position, wherein the movable needle shield can
be disengaged from the needle base protrusions by rotating the movable
shield to be moved from the first to the second position, and wherein
the needle shield is in contact with the needle base at both positions.
14. The syringe of claim 13 wherein needle base has at least one
needle base protrusion, and wherein the needle shield has at least
one indention at a second end, and wherein the needle shield is
locked in the second position when at least one needle base protrusion
meets with at least one needle shield indention.
15. The syringe of claim 13 wherein the first end of the syringe
barrel is tapered, and further comprising a plunger within the syringe
barrel, the plunger having an injection tip protrusion capable of
advancing into and forcing fluid out of the tapered end of the syringe
barrel.
16. The syringe of claim 13 wherein the second end of the syringe
barrel has on its interior at least one plunger stopping protrusion,
wherein at least one of the plunger stopping protrusions is capable
of contacting a portion of a plunger in the syringe barrel to prevent
its removal from the syringe barrel.
17. The syringe of claim 13 further comprising a rear cap receptacle
on the second end of the syringe barrel and capable of receiving
a rear cap.
18. The syringe of claim 17 further comprising a rear cap, which
contains at least one sterility ring for contacting a portion of
the rear cap receptacle.
Safety syringe description
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority under 35 U.S.C. .sctn.119(a) to
Korean Utility Model Application No. 2603/2001 filed in Korea on
Feb. 3 2001.
TECHNICAL FIELD
The present invention is directed to a disposable safety syringe
constructed so that an attached needle may be disposed of safely
and separately after use, additionally configured so that all fluid
is forced from the barrel of the syringe, and further constructed
so that the plunger may not be fully removed from the barrel, preventing
inadvertent loss of fluid that has been drawn into the syringe barrel.
BACKGROUND OF THE INVENTION
A conventional disposable syringe is constructed such that fluid
to be injected is forced out of the barrel of the syringe when pressure
is exerted on the syringe plunger. The barrel of a conventional
syringe typically tapers at one end to accommodate the base of a
needle.
When the plunger is forced into the barrel, the end of the plunger
cannot fully enter this tapered portion of the barrel. Thus, a small
amount of the injection fluid is left unaffected by pressure exerted
by the plunger, and remains in the tapered portion of the barrel.
Although this remaining amount of fluid (e.g. 0.07 cc) may seem
negligible, repeated waste of this small quantity leads to economic
loss.
A conventional syringe also lacks a mechanism to prevent one from
pulling the plunger completely out of the barrel. If one mistakenly
removes the plunger while drawing fluid into the barrel, the fluid
can be lost.
Conventional disposable needles are typically covered by a cap
for protection. This cap is removed before use, and replaced prior
to needle disposal. If this conventional needle cap inadvertently
falls off, individuals handling the needle, such as health care
professionals and sanitation workers, may be pricked by the exposed
needle, potentially exposing themselves to blood borne diseases.
SUMMARY OF THE INVENTION
The present invention remedies the aforementioned problems by incorporating
several novel features. First, a plunger tip of new design allows
all fluid to be forced from the tapered portion of the syringe barrel
into the needle. Second, a slanted protrusion on the interior of
the barrel prevents a user form inadvertently pulling the plunger
fully out of the barrel. Third, after an injection is given, a newly
designed protective needle shield can be moved and locked into position,
shielding the needle from touch. A disposal cap may then be placed
on the top of this shield. The movement of this shield into position
also allows dislocation of the protected shield and needle from
the syringe, allowing for separate needle disposal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the disassembled components of an embodiment of the
disclosed syringe and needle, as well as the various protective
caps.
FIG. 2 is a cross-sectional view of an embodiment of the assembled
syringe and needle with end caps, as it would appear prior to use.
FIG. 3 is a cross-sectional view of an embodiment of the syringe
with attached needle after the needle cap and rear cap have been
removed, wherein the plunger has been fully driven into the syringe
barrel.
FIG. 4 is a cross-sectional view of an embodiment of the syringe
with attached needle after the protective needle shield has been
raised and locked into position, and the disposal cap has been placed
on the protective needle shield.
FIG. 5 is a cross-sectional view of the needle base, the protective
needle shield, and the disposal cap after their removal from the
syringe barrel.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1 in one embodiment of the invention, the syringe
barrel 1 has a first end and a second end. On the first end, there
is a tapered portion of the barrel 26 upon which a needle base
5 containing a needle 8 can be placed. On the second end of the
barrel there is a finger flange 14 where fingers may be placed
during use to allow one to advance or withdraw a plunger 2 within
the barrel 1. Also on the second end of the barrel, distal to the
finger flange 14 is a rear cap receptacle 15. Threads on the exterior
of the rear cap receptacle 15 correspond to threads located on the
interior of a rear cap 7. This rear cap 7 can be disengagably connected
to the barrel 1 of the syringe via the rear cap receptacle 15. One
or more sterility rings 11 also located on the interior of the
rear caps form an airtight seal with the rear cap receptacle 15.
Referring again to FIG. 1 the plunger 2 has a thumb rest 18 at
one end, and an injection tip 3 upon which is mounted an injection
tip protrusion 16 at the other.
Referring to FIGS. 2-4 the injection tip 3 is also encircled by
one or plunger stopping ribs 17. These ribs 17 prevent a user from
pulling the plunger 2 completely out of the barrel 1 by catching
on slanted plunger stopping protrusions 13 located on the interior
of the barrel 1. The inability to remove the plunger 2 completely
from the barrel 1 assures that no fluid is inadvertently lost while
attempting to draw it into the barrel.
In the assembled invention, a plunger 2 is contained within the
syringe barrel 1. When the plunger 2 is forced into the barrel 1
completely, all fluid in the both the barrel 1 and the tapered portion
of the barrel 26 is forced through the barrel outlet 12. Fluid is
forced from the tapered portion of the barrel 26 by the injection
tip protrusion 16 which is capable of entering the tapered portion
of the barrel 26. This injection tip protrusion 16 will advance
until it comes into contact with the back of the needle 9.
Additionally, in the assembled invention, a protective needle shield
4 surrounds the syringe barrel 1 and needle base 5. This needle
shield 4 holds the needle base 5 in place atop the tapered portion
of the barrel 26. A thread 20 on the interior of the needle shield
4 holds needle base protrusions 10 located at the bottom of the
needle base 5.
Before use, a needle cap 6 shields the needle 8 and is held in
place by contacts between one or more sterility rings 11 on the
interior of the needle cap 6 with the exterior of the needle base
5.
When preparing to use the invention, the rear cap 7 and needle
cap 6 are removed. After an injection is given, one may grasp and
twist the needle shield 4 slightly by grasping the detachment handles
21. This action will disengage the needle base protrusions 10 at
the bottom of the needle base 5 from the thread 20 on the interior
of the needle shield 4. As shown in FIG. 4 the needle protective
shield 4 is then moved upwards to cover the exposed needle 8 and
becomes locked into a shielding position when the needle base protrusions
10 glide over slanted protrusions 22 and are stopped by an adjacent
catching ledge 24 both (22 and 24) located on the interior of the
needle protective shield 4. The needle base protrusions 10 now rest
in an indented space 23 between the slanted protrusions and the
catching ledge 24 both on the interior of the shield 22.
At this time, the needle base 5 containing the used needle 8
is securely shielded by the needle protective shield 4 as the needle
base protrusions 10 are now stuck in the indention 23 between the
slanted protrusions 22 and the catching ledge 24. Thus, the use
of the needle protective shield not only secures the needle for
safety, but also prevents reuse of an unsanitary needle.
The movement of the needle shield 24 over the exposed needle 8
also allows one to disconnect the needle base 5 from the tapered
portion of the barrel 26.
Once the needle protective shield reaches this shielding position,
the needle can be further protected by placing a disposable cap
25 onto the disposal cap receptacle 19 of the needle protective
shield 4 with the disposable cap 25 coming to rest on the detachment
handles 21 at the base of the disposal cap receptacle 19.
As shown in FIG. 5 the combination of the needle base 5 needle
protective shield 4 and disposable cap 25 may now be safely removed
from the syringe barrel 1 and may be separately and appropriately
discarded.
The syringe and attached needle, with rear cap 7 and needle cap
6 in place, can be sterilized by placing it inside a common sterilization
chamber. The sterility maintenance rings 11 located on both the
interior of the needle cap 6 and rear cap 7 serve in prolonging
the sterility of the invention.
In summary, the present invention includes several novel features,
all of which improve the safety and efficacy this disposable syringe
and needle. First, by way of a newly designed plunger injection
tip, all remnants of the injection fluid are forced from the barrel
into the needle. Second, full removal of the plunger from the barrel
is prevented by a combination of ribs surrounding the injection
tip that catch on slanted protrusions located inside the syringe
barrel. Third, a newly designed needle protective shield, which
encircles the barrel and needle base may be moved into position
after an injection is given, shielding the needle from touch, and
also dislocating the needle protective shield and needle base from
the syringe. A disposal cap may then be placed over the top of the
needle protective shield, further preparing the shielded needle
for appropriate disposal. |