Safety syringe abstract
A safety syringe for taking blood has a hollow barrel, a seal,
a tube and a needle hub. The hollow barrel has an outside surface,
a proximal open end and a distal closed end. The seal with an inner
needle is mounted inside the hollow barrel. The tube has a proximal
open end and a distal open end and is attached longitudinally to
the outside surface of the hollow barrel. The needle hub is mounted
inside the tube, and the needle can extend out of the distal open
end of the tube. A first through hole defined in the hollow barrel
and a second through hole is defined in the tube align with the
first through hole. When taking blood, the needle is extended out
from the distal end of the tube to take a blood sample and a vacutainer
is inserted into the hollow barrel to collect a blood sample. The
used needle is retracted into the tube after use to keep people
from getting injured or infected.
Safety syringe claims
What is claimed is:
1. A safety syringe for taking blood comprising a hollow barrel
having a distal closed end; a proximal open end; a sidewall; an
outside surface; and a first through hole defined through the sidewall;
a seal mounted inside the hollow barrel; an inner needle being L-shaped
with an inner channel and mounted on the seal; a tube connected
to the hollow barrel, being cylindrical and having a proximal open
end; a distal open end; a sidewall; a lip defined inside the distal
open end; a guide slot defined longitudinally through the tube and
having a proximal end and a distal end; two locking slots defined
through the tube and locking slots being perpendicular to the guide
slot and communicating with the guide slot; a second through hole
defined through the sidewall of the tube and aligning and communicating
with the first through hole of the hollow barrel; and a needle hub
slidably mounted inside the tube and having a stopper having a top
surface, a bottom surface and a cylindrical surface; a needle with
a longitudinal fluid passage and mounted in the bottom surface of
the stopper; a fluid channel defined through the stopper and having
a first end defined through the bottom surface of the stopper and
connected to the needle; and a second end; a guide stub attached
to the cylindrical surface of the stopper and moveably received
in the guide slot in the tube; and a tapered hole formed in the
cylindrical sidewall and communicating with the second end of the
fluid channel so the tapered hole aligns with the second through
hole when the needle of the needle hub is fully extended out the
tube.
2. The safety syringe for taking blood as claimed in claim 1 wherein
the hollow barrel and the tube are integrally formed together.
3. The safety syringe for taking blood as claimed in claim 1 wherein
the seal and the hollow barrel are integrally formed together.
4. The safety syringe for taking blood as claimed in claim 1 further
comprises a spring mounted inside the tube and the needle is inserted
through the spring.
5. The safety syringe for taking blood as claimed in claim 4 further
comprises a plug mounted inside the proximal open end of the tube.
6. The safety syringe for taking blood as claimed in claim 1 wherein
the locking slots comprises a retracted locking slot formed near
the proximal end of and perpendicular to the guide slot, and an
extended locking slot is formed at the distal end of and perpendicular
to the guide slot.
7. The safety syringe for taking blood as claimed in claim 1 wherein
the inner needle further comprises an elastic sheath mounted on
the inner needle.
Safety syringe description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a syringe, and more particularly
to a safety syringe that can safely hold a used needle and prevent
users from getting hurt by the used needle.
2. Description of Related Art
There are two types of conventional syringes used for taking blood,
one has a hollow barrel, a plunger and a needle hub, and the other
has a short holder, an inner needle and a needle hub. The plunger
of the first type is received inside the hollow barrel, and the
needle hub is connected to the hollow barrel. The short holder of
the second type has an outside surface, a bottom surface and an
inner space. The needle hub is mounted on the bottom surface of
the outside surface and the inner needle mounted on inner space
and connects to the needle hub.
When using the first type of the conventional syringe, a user takes
blood into the hollow barrel then inserts the collected blood into
a vacuum tube. When using the second type of the conventional syringe,
the needle hub is inserted into a vein and a vacutainer is connected
to the inner needle inside the short holder. Because of the attraction
of the vacutainer and the blood pressure, blood will flow into the
vacutainer slowly.
However, the used needles extended outside the hollow barrel or
the short holder of the conventional syringes are easily hurt users
after taking blood. To keep nurses, doctors or health workers who
deal with discarded syringes from getting injured or infected by
used needles, a safety syringe for taking blood is needed. In another
aspect, the short holder of the second conventional syringe is too
easily reused to hold a new needle and unscrupulous staff may be
tempted to reduce costs in this way whereby serious unsanitary conditions
will be met.
To overcome the shortcomings of conventional syringes, the present
invention provides a safety syringe to mitigate or obviate the aforementioned
problem.
SUMMARY OF THE INVENTION
The primary objective of the present invention is to provide a
safety syringe for taking blood. The safety syringe for taking blood
in accordance with the present invention comprises a hollow barrel,
a seal, a tube and a needle hub.
The hollow barrel has a proximal open end, a distal closed end,
an outside surface, a dovetail keyway and a first through hole.
The seal with an inner needle is mounted inside the hollow barrel.
The tube has a proximal open end and a distal open end and is mounted
on the hollow barrel. The needle hub and a spring are mounted inside
the tube, and the needle selectively extends from the proximal open
end of the tube. The first through hole is defined in the hollow
barrel through the dovetail keyway, and a second through hole is
defined in the tube. The first through hole faces the second through
hole.
When using the syringe in accordance with the present invention,
the needle hub extends out of the tube to draw a blood sample and
a vacutainer is inserted into the hollow barrel to collect blood
sample. When taking a blood sample is finished, the used needle
hub is retracted inside the tube to keep the used needle from injuring
or infecting a person.
Other objectives, advantages and novel features of the invention
will become more apparent from the following detailed description
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a first embodiment of
a safety syringe for taking blood in accordance with the present
invention;
FIG. 2 is a side plan view in partial section of the safety syringe
for taking blood in FIG. 1 with a covered needle in the tube;
FIG. 3 is an operational side plan view in partial section of the
safety syringe for taking blood in FIG. 1 with a vacutainer;
FIG. 4 is an operational side plan view in partial section of the
safety syringe for taking blood in FIG. 1 with the needle extended
out the tube and the inner needle is inserted into the vacutainer;
FIG. 5 is a side plan view in partial sectional of a second embodiment
of the safety syringe for taking blood in accordance with the present
invention; and
FIG. 6 is a side plan view in partial sectional of a third embodiment
of the safety syringe for taking blood in accordance with the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 1 and 2 a safety syringe of a first embodiment
in accordance with the present invention has a hollow barrel (10),
a seal (20), a tube (30) and a needle hub (40):
The hollow barrel (10) is cylindrical and has a distal closed end
(not numbered), a proximal open end (not numbered), a sidewall (not
numbered), an outside surface (not numbered), an annular flange
(11), a dovetail keyway (12) and a first through hole (13). The
annular flange (11) is defined radially around and extends out from
the proximal open end. The dovetail keyway (12) is formed longitudinally
on the outside surface of the hollow barrel (10). The first through
hole (13) is defined through the sidewall in the dovetail keyway
(12) near the distal closed end.
The seal (20) has a proximal end (not numbered), a distal end (not
numbered), an inner needle (21) and an elastic sheath (23) and is
mounted inside the distal end of the hollow barrel (10). The inner
needle (21) is L-shaped with an inner channel and has a proximal
end (not numbered) and a distal end (not numbered). The distal end
is perpendicular to the proximal end and is mounted inside the seal
(20) and the inner channel defines a hole (22) at the distal end
forms an egress in the seal (20). The elastic sheath (23) is mounted
on the inner needle (21). With further reference to FIG. 5 a second
embodiment of the safety syringe for taking blood is shown, wherein
the seal also can be inside the hollow barrel (80) in other ways
such as integrally formed together with the hollow barrel (80).
The tube (30) is connected to the hollow barrel (10) and has an
outside surface (not numbered), a dovetail key (31), a lip (32),
a distal open end (not numbered), a proximal open end (not numbered),
a guide slot (33), a sidewall (not numbered) and a second through
hole (36). The dovetail key (31) is formed longitudinally on and
extends from the outside surface and engages the dovetail keyway
(12) on the hollow barrel (10). The lip (32) is formed at the distal
open end and protrudes radially inward so that the diameter of the
distal open end is smaller than the proximal open end. The guide
slot (33) has a proximal end (not numbered), a distal end (not numbered),
a retracted locking slot (34) and an extended locking slot (35)
and is defined longitudinally through the sidewall of the tube (30)
diametrically opposite from the dovetail key (31). The proximal
end of the guide slot (33) can be open and is at the proximal open
end of the tube (30). The retracted locking slot (34) is formed
near the proximal end of and perpendicular to the guide slot (33).
The extended locking slot (35) is formed at the distal end of and
perpendicular to the guide slot (33). The second through hole (36)
is defined through sidewall of the tube (30) and the dovetail key
(31) and faces and aligns with the first through hole (13) defined
through the hollow barrel (10). With further reference to FIG. 6
a third embodiment of the safety syringe is shown, wherein the tube
(91) also can connect to the hollow barrel (90) in other ways such
as being integrally formed together with the hollow barrel (90).
As shown in FIGS. 5 and 6 the seal in each of the embodiments of
FIGS. 5 and 6 is integrally formed together with the hollow barrels
80 and 90 respectively.
The safety syringe in accordance with the present invention further
comprises a spring (50) and a plug (60). The spring.(50) has a distal
end (not numbered) and a proximal end (not numbered) and is inserted
into the tube (30). The distal end of the spring (50) abuts the
lip (32) in the distal open end of the tube (30).
The needle hub (40) is slidably mounted inside the tube (30) and
has a needle (41), a stopper (42), a guide stub (43), a fluid channel
(not numbered) and a tapered hole (44). The stopper (42) is cylindrical
and has a top surface (not numbered), a bottom surface (not numbered)
and a cylindrical surface (not numbered). The bottom surface abuts
the lip (32) of the tube (30). The needle (41) has a longitudinal
fluid passage (not shown), and passes through the spring (50) and
is mounted in the bottom surface of the stopper (42). The fluid
channel has a first end (not numbered) and a second end (not numbered).
The first end is extended through the bottom surface of the stopper
(42), and the second end is extended through the cylindrical surface
of the stopper (42). The first end of the fluid channel is connected
to the needle (41), and the second end of the fluid channel is connecting
to the tapered hole (44) that is formed in the cylindrical surface.
With further reference to FIGS. 3 and 4 the guide stub (43) is
attached to the cylindrical surface of the stopper (42) so the tapered
hole (44) aligns with the second through hole (36) when the guide
stub (43) is fully seated in the extended locking slot (35).
The needle hub (40) may optionally include a needle cap (400).
The needle cap (400) is detachably attached to the bottom surface
of the stopper (42) to cover the needle (41) to protect the needle
(41) from contaminants and to keep the needle (41) from injuring
a person when the needle (41) is being extended from the tube (30).
The needle cap (400) is removed from the needle (41 ) and discarded
to draw a blood sample into a vacutainer (70) inside the hollow
barrel (10).
The plug (60) is cylindrical and is mounted securely inside the
distal open end of the tube (30) to hold the needle hub (40) inside
the tube (30).
With reference to FIGS. 3 and 4 when taking blood from a patient's
body, the user moves the stopper (42) from the retracted locking
slot (34) to the guide slot (33) by means of holding the guide stub
(43). The stopper (42) is slid toward the distal end of the guide
slot (33) and is moved into the extended locking slot (35) to hold
the needle (41) outside the distal open end of the tube (30) and
to align the tapered hole (44) with the second through hole (36)
in the tube (30). The spring (50) is compressed between the lip
(32) at the proximal open and the bottom surface of the needle hub
(40).
The vacutainer (70) is inserted toward the proximal end of the
hollow barrel (10) and the elastic sheath (23) is pushed toward
the seal (20) so a blood sample can be drawn through the needle
(41), the fluid channel, the second through hole (36) and the first
through hole (13) of the hollow barrel (10), and then into the vacutainer
(70).
The guide stub (43) is released from the extended locking slot
(35), and the spring (50) pushes the guide stub (43) toward the
proximal end of the guide slot (33). The spring (50) also holds
the needle hub (40) and the needle (41) in the tube (30).
The needle hub (40) of the safety syringe for taking blood in accordance
with present invention can be retracted inside the tube (30) so
that the used needle (41) will not injure users or contaminate the
users. Also, the safety syringe for taking blood can be discarded
and prevents the used hollow barrel (10) from being reused.
Even though numerous characteristics and advantages of the present
invention have been set forth in the foregoing description, together
with details of the structure and function of the invention, the
disclosure is illustrative only, and changes may be made in detail,
especially in matters of shape, size, and arrangement of parts within
the principles of the invention to the full extent indicated by
the broad general meaning of the terms in which the appended claims
are expressed. |