Safety syringe abstract
The safety syringe has a hollow barrel, a needle hub, a sleeve
and a plunger. The needle hub is mounted on the hollow barrel and
has a needle, a hub and a stopper. The needle is mounted on the
hub and the stopper is mounted inside the hub. The hub has channels
through which medication or blood can pass. The sleeve is mounted
on the needle hub. The plunger is mounted slidably inside the hollow
barrel. The used needle is retracted into the tube after use by
a vacuum after seating the stopper and retracting the plunger to
keep people from getting injured or infected.
Safety syringe claims
1. A safety syringe comprising; a hollow barrel having a distal
end, a proximal end, an outside surface, an inner surface, an exterior
thread formed on the outside surface near the distal end, multiple
longitudinal ribs formed on the inner surface near the distal end,
and a finger flange defined at the proximal end and protrudes from
diametrically opposite sides, a needle hub mounted on the hollow
barrel at the distal end and having a needle having a fluid channel
defined though the needle, a hub connected to the needle and having
a proximal end, a distal end, a middle, an outside surface, an inner
surface, multiple longitudinal ribs formed on the outside surface
and engaged by the longitudinal ribs inside the hollow barrel, an
external thread formed at the middle of the hub near the distal
end, a fluid channel defined through the distal end and the external
thread and communicating with the fluid channel in the needle, a
cavity defined through the hub, communicating with the fluid channel
in the hub and having a depth, and at least one channel defined
in the inner surface of the hub, and communicating with the cavity
and having a length, and a stopper slidably mounted inside the cavity
in the hub and having a height, a sleeve mounted on the hub and
having an inner surface, a front end, a rear end, an outer interior
thread defined in the inner surface at the front end, corresponding
to and screwing onto the external thread on the hub, and an inner
interior thread defined in the inner surface at the rear end, corresponding
to and screwing onto the threaded end of the hollow barrel, and
a plunger slidably mounted inside the hollow barrel and having a
distal end, a proximal end, and a sliding stopper mounted on the
distal end of the plunger.
2. The safety syringe as claimed in claim 1 wherein the distal
end of the hub is tapered and mounted inside the needle.
3. The safety syringe as claimed in claim 1 wherein the hub further
comprises a flange formed at the proximal end and extending out
from the proximal end to seal the hollow barrel.
4. The safety syringe as claimed in claim 1 wherein the stopper
has a transverse Y-shaped channel defined in the stopper.
5. The safety syringe as claimed in claim 1 wherein four channels
are defined in the inner surface of the hub.
6. The safety syringe as claimed in claim 1 wherein the length
of the channel is shorter than the depth of the cavity.
7. The safety syringe as claimed in claim 1 wherein the plunger
further comprises an annular notch defined in the plunger near the
sliding stopper.
8. The safety syringe as claimed in claim 2 wherein the hub further
comprises a flange formed at the proximal end and extends out from
the proximal end to seal up the hollow barrel.
9. The safety syringe as claimed in claim 8 wherein four channels
are respectively defined in the inner surface of the hub.
10. The safety syringe as claimed in claim 9 wherein the plunger
further comprises an annular notch defined in the plunger near the
sliding stopper.
Safety syringe description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a syringe, and more particularly
to a safety syringe that can safely hold a used needle and prevent
the syringe from being used more than once.
[0003] 2. Description of Related Art
[0004] Due to contagious diseases, needles of syringes and even
the hollow barrels and plungers, should not be used again and should
be discarded immediately after use. Also, to keep nurses, doctors
or medical workers who deal with discarded syringes from getting
injured or infected by used needles, safety syringes are needed.
[0005] A conventional safety syringe has a hollow barrel, a plunger
and a needle hub. To prevent a used needle from injuring a user,
the needle hub is pulled back inside the hollow barrel. The needle
hub of the conventional safety syringe often has some locking elements
formed on the needle hub to lock the needle hub to the plunger so
the used needle hub can be pulled back inside the hollow barrel.
However, the structure of the locking elements formed on the needle
hub is often complex. Further, the complex structure increases the
cost and results in safety syringes not being available to all.
[0006] To overcome the shortcomings of conventional safety syringes,
the present invention provides a safety syringe to mitigate or obviate
the aforementioned problem.
SUMMARY OF THE INVENTION
[0007] The primary objective of the present invention is to provide
a safety syringe that has a simpler structure than the conventional
safety syringe and improves safety.
[0008] The safety syringe in accordance with the present invention
comprises a hollow barrel, a needle hub, a sleeve and a plunger.
The needle hub is mounted on the hollow barrel and has a needle,
a hub and a stopper. The needle is mounted on the hub and the stopper
is mounted inside the hub. The hub has channels through which medication
or blood can pass. The sleeve is mounted on the needle hub. The
plunger is mounted slidably inside the hollow barrel. The used needle
is retracted into the tube after use by a vacuum after seating the
stopper and retracting the plunger to keep people from getting injured
or infected.
[0009] 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
[0010] FIG. 1 is an exploded perspective view of a first embodiment
of a safety syringe in accordance with the present invention;
[0011] FIG. 2 is a side view in partial section of the safety syringe
in FIG. 1;
[0012] FIG. 3 is a cross sectional rear view of the safety syringe
along line 3-3 in FIG. 2;
[0013] FIG. 4 is a side view in partial section of the safety syringe
in FIG. 1 with the plunger totally pressed completely into the hollow
barrel;
[0014] FIG. 5 is a side view in partial section of the safety syringe
in FIG. 1 with the cap being loosened from the needle hub;
[0015] FIG. 6 is a side view in partial section of the safety syringe
in FIG. 1 with the plunger being broken;
[0016] FIG. 7 is a side view in partial section of a second embodiment
of a safety syringe in accordance with the present invention; and
[0017] FIG. 8 is a cross sectional rear view of the safety syringe
along line 8-8 in FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] With reference to FIGS. 1 to 3 a first embodiment of a
safety syringe (10) in accordance with the present invention has
a hollow barrel (11), a needle hub (20), a sleeve (30) and a plunger
(40).
[0019] The hollow barrel (11) is cylindrical and has a distal end,
a proximal end, an outside surface, an inner surface, an exterior
thread (12), multiple longitudinal ribs (13) and a finger flange
(14). The exterior thread (12) is formed on the outside surface
near the distal end. The longitudinal ribs (13) are formed on the
inner surface near the distal end. The finger flange (14) is defined
at the proximal end and protrudes from diametrically opposite sides.
[0020] The needle hub (20) is mounted on the hollow barrel (11)
at the distal end and has a needle (21), a hub (22) and a stopper
(23A). The needle (21) is mounted on the hub (22) and has a fluid
channel defined though the needle (21). The hub (22) has a proximal
end, a distal end (223), a middle, an outside surface, an inner
surface, multiple longitudinal ribs (221), an optional flange (222),
an external thread (224), a fluid channel (225), a cavity (226)
and at least one channel (227). In a preferred embodiment, the distal
end (223) is tapered and is mounted inside the needle (21). In a
certain embodiment, the needle (21) may directly form on the distal
end of the hub (22). The longitudinal ribs (221) are formed on the
outside surface and engaged by the longitudinal ribs (13) inside
the hollow barrel (11). The flange (222) is formed at the proximal
end and extends out from the proximal end to seal the hollow barrel
(11). The external thread (224) is formed at the middle of the hub
(20) near the distal end (223). The fluid channel (225) is defined
through the distal end (223) and the external thread (224). The
cavity (226) is defined through the hub (22) and communicates with
the fluid channel (225) and has a depth. The at least one channel
(227) is defined in the inner surface of the hub (22), communicates
with the cavity (226) and has a length. In a preferred embodiment,
four channels (227) are defined in the inner surface of the hub
(22). In a preferred embodiment, the length of the channel (227)
is shorter than the depth of the cavity (226). The stopper (23A)
is slidably mounted inside the cavity (226) in the hub (22) and
has a height. In a preferred embodiment, the height of the stopper
(23A) is equal to the depth of the cavity (226).
[0021] With further reference to FIGS. 7 and 8 a second embodiment
of the safety syringe in accordance with the present invention has
a stopper (23B) with a transverse Y-shaped channel (24B) for liquid
medication or blood can pass through quickly. In a preferred embodiment,
the height of the stopper (23B) is shorter than the depth of the
cavity (226). Before using the safety syringe, the stopper (23A,
23B) is partially mounted inside the cavity (226).
[0022] The sleeve (30) is mounted on the hub (22) and has an inner
surface, a front end (32), a rear end (31), an outer interior thread
(33) and an inner interior thread (34). The outer interior thread
(33) is defined in the inner surface at the front end (32), corresponds
to and screws onto the external thread (224) on the hub (22). The
inner interior thread (34) is defined in the inner surface at the
rear end (31), corresponds to and screws onto the threaded end (12)
of the hollow barrel (11).
[0023] The plunger (40) is slidably mounted inside the hollow barrel
(11) and has a distal end, a proximal end, a sliding stopper (41)
and an optional annular notch (42). The sliding stopper (41) is
mounted on the distal end of the plunger (40), and the annular notch
(42) is defined in the plunger (40) near the sliding stopper (41).
[0024] With further reference to FIG. 4 the safety syringe is
filled with medication by pulling the plunger (40) back to draw
the medication through the fluid channel (225) and the channels
(227) into the hollow barrel (11). To inject the medication, the
plunger (40) is pushed, and the medication moves alone the channels
(227), the fluid channel (225) and the needle (21).
[0025] With reference to FIGS. 4 to 6 the safety features of the
safety syringe are implemented by pushing the stopper (23A) firmly
into the cavity (226), unscrewing the sleeve (30) and retracting
the plunger (40). The stopper (23A) seals the channels (227) and
the fluid channel (225) and keeps the fluid channel (225) from communicating
with the cavity (226) in the hub (22). The cap (30) can be unscrewed
from the needle hub (22) because the longitudinal ribs (221) on
the hub (22) engage with the longitudinal ribs (13) on the inner
surface of the hollow barrel (11) and keep the hub (22) from rotating.
The plunger (40) is pulled back, which generates a vacuum in the
hollow barrel (11) pulls the needle (21) into the hollow barrel
(40). Then the plunger (40) is broken at the annular notch (42)
to keep the needle (21) from being pushed out of the hollow barrel
(40) again.
[0026] 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. 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. |