Safety syringe abstract
A safety syringe includes: an annular groove annularly recessed
in a front surface of a plunger slidably held in the syringe to
be engageable with a needle head portion formed on a rear portion
of a hollow needle eccentrically mounted in a front portion of the
syringe, with the annular groove having a longitudinal section formed
as a biasing socket engageable with the needle head portion for
biasing the needle obliquely within the syringe when retracting
the plunger and the needle into the syringe, thereby preventing
an outward protruding of the retracted needle for safety and hygienic
purpose.
Safety syringe claims
I claim:
1. A safety syringe comprising:
a syringe means having a sleeve portion eccentrically formed in
a front portion of a syringe cylinder of said syringe means, and
a front plug embedded in the front portion of said syringe cylinder,
with said syringe cylinder defining a syringe axis in a longitudinal
center line of said syringe cylinder;
a hollow needle device having a needle portion formed in a front
portion of said needle device normally inserted in a tunnel eccentrically
formed in said front plug of said syringe means defining a needle
axis in a longitudinal center of said needle device with the needle
axis being parallel to said syringe axis and being longitudinally
aligned with a center line of the tunnel and of said sleeve portion
of said syringe means and protruding outwardly through said sleeve
portion of said cylinder for injection use, and a needle head portion
elliptically shaped formed on a rear portion of said needle device;
and
a plunger means having a plunger reciprocatively held in the syringe
cylinder for boosting a liquid medicine in the syringe means to
be injected into a patient through the hollow needle device, and
an annular groove annularly recessed in a front surface of said
plunger having a longitudinal section of said annular groove formed
as an elliptically shaped biasing socket to be engageable with said
needle head portion elliptically shaped of said needle device for
operatively biasing said needle device in an acute angle deviated
from the tunnel, whereby upon a frontward pushing of said plunger
for boosting the liquid medicine in the cylinder for injection use,
the needle head portion will be engaged with the biasing socket
of said annular groove of the plunger; and
upon a retraction of the plunger, the needle device will be retracted
into the syringe cylinder and obliquely biased by said biasing socket
of said plunger for preventing an outward protruding of the retracted
needle device for safety and hygienic purpose.
2. A safety syringe according to claim 1 wherein said front plug
in said syringe cylinder includes a liquid-repelling extension concentrically
formed in a rear surface of the front plug inserted in the front
portion of the syringe cylinder having a flat surface portion recessed
in the liquid-repelling extension and coplanar to the rear surface
of the front plug for receiving the needle head portion of the needle
device within the flat surface portion, with the liquid-repelling
extension having a longitudinal section of arcuate shape and engageable
with the annular groove recessed in the plunger for operatively
squeezing the liquid medicine outwardly as filled into the annular
groove when pumping the plunger towards the front plug for finishing
the injecton operation for saving any medicine filled in the annular
groove.
Safety syringe description
The previously filed invention disclosed a safety syringe comprising:
a syringe means (1) for filling liquid medicine (4) therein; a needle
device (2) secured in a front portion of the syringe means (1) for
injection use having a needle head portion (23) formed on a rear
portion of the needle device (2), and a plunger means (3) slidably
held in the syringe mean (1) for boosting the liquid medicine (4)
in the syringe means (1) to be injected into a patient through the
needle device (2) having a biasing socket (32) recessed in a front
portion of the plunger means (3) engageable with the needle head
portion (23) of said needle device (2) for biasing said needle device
(2) obliquely within the syringe means (1) when retracting the plunger
means (3) and the needle device (2) into the syringe means (1),
thereby preventing an outward protruding of a retracted needle device
for preventing injury or infectious contamination by the needle
device (2) to environmental surroundings.
The needle device (2) of such a safety syringe is normally provided
in a central portion of the syringe means (1), which is suitable
for hypodermic or intramuscular injection. However, if such a syringe
is used for intravenous or intravascular injection of larger quanity
of liquid medicine (4) filled in the syringe cylinder (11) such
as a volume of 30 cc, 50 cc, or 100 cc of the liquid medicine. The
needle (2) should be eccentrically formed in the syringe cylinder
for an ergonomic injection by a nurse or a doctor since the needle
and the syringe cylinder can be held in a direction parallel and
close to the patient's vein or blood vessels.
If the inventor's earlier application (U.S. Ser. No.: 07/952593)
is inferentially used for an intravenous injection of larger injection
quanlity, the needle (2) should be eccentrically mounted in the
syringe cylinder (11). Meanwhile, the single biasing socket (32)
should also be eccentrically moved in order to engage with the needle
head portion (23) of the needle (2). It will be very difficult and
inconvenient for matching a needle head portion (23) of an eccentrically-positioned
needle (2) with the single biasing socket (32).
SUMMARY OF THE INVENTION
It is therefore provided with a safety syringe including: an annular
groove annularly recessed in a front surface of a plunger slidably
held in the syringe to be engageable with a needle head portion
formed on a rear portion of a hollow needle eccentrically mounted
in a front portion of the syringe, with the annular groove having
a longitudinal section formed as a biasing socket engageable with
the needle head portion for biasing the needle obliquely within
the syringe when retracting the plunger and the needle into the
syringe, thereby preventing an outward protruding of the retracted
needle for safety and hygienic purpose.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of the present invention before injection
operation.
FIG. 2 shows a plunger coupled with a needle head portion of a
needle device of the present invention.
FIG. 3 shows a biased needle retracted in a syringe cylinder in
accordance with the present invention.
FIG. 4 shows a prevention of an outwardly protruded needle device
when retracted in the syringe cylinder in accordance with the present
invention.
FIG. 5 is an enlarged view of the biased needle and the plunger
of the present invention.
FIG. 6 is a front view of the plunger when viewed from 6--6 direction
of FIG. 1.
FIG. 7 is a bottom view of a front plug in the syringe cylinder
when viewed from 7--7 direction of FIG. 1.
DETAILED DESCRIPTION
As shown in the drawing figures, the present invention comprises:
a syringe means 1 a needle device 2 mounted in an eccentric front
portion of the syringe means 1 and a plunger means 3 slidably held
in the syringe means 1 for boosting and injecting a liquid medicine
4 into a patient's blood vessel.
The syringe means 1 includes: a syringe cylinder 11 having a hollow
bore portion 10 defined in the syringe cylinder 11 and a syringe
axis 100 longitudinally existing in a central portion of the syringe
cylinder 11 a sleeve portion 12 formed in an eccentric front portion
of the cylinder 11 contracted from the cylinder 11 having a needle
port 121 formed in a front opening of the sleeve 12 a front plug
13 having a plug tip portion 131 embedded in the sleeve portion
12 and a plug shoulder portion 133 embedded in a front portion of
the cylinder 11 connected with the tip portion 131 and a tunnel
130 formed in the plug 13 communicating the needle port 121 for
inserting the needle device 2 in the tunnel 130 a syringe handle
14 formed on a rear end portion of the cylinder 11 and a liquid-repelling
extension 15 arcuately or concentrically formed on a rear surface
135 of the front plug 13 with a flat surface portion 151 disposed
around the tunnel 13 recessed in the liquid-repelling extension
15 and coplanar to the rear surface 135 of the plug 13.
The plug 13 has a plurality of ring grooves circumferentially formed
on the tip portion 131 and the shoulder portion 133 of the plug
13 engageable with several ring extensions 132 134 formed in the
sleeve 12 and cylinder 11 for frictionally holding the plug 13 in
the syringe means 1 and also for preventing liquid leakage from
the cylinder 11.
The needle device 2 includes: a needle portion 21 having a tip
end 211 a hank portion 22 connected with the needle portion 21
having a plurality of needle rings 221 circumferentially formed
on the shank portion 22 for firmly engaging the shank portion 22
in the tunnel 130 of the syringe means 1 for protruding the needle
portion 21 beyond the needle port 121 of the syringe means 1 a
needle head portion 23 formed on a rear portion of the shank portion
22 protruding rearwardly beyond a plug surface 135 formed on a rear
end surface of the plug 13 to be engageable with a biasing socket
of an annular groove 32 of the plunger means 3 a needle hole 20
formed through the needle portion 21 the shank portion 22 and the
needle head portion 23 for passing liquid medicine 4 therethrough
for injection use, a needle axis 200 longitudinally existing in
a central portion of the needle device 2 normally parallel to the
syringe axis 100 when eccentrically mounted in the syringe means
1 and normally aligned with a longitudinal center line of the tunnel
130 of the sleeve portion 12 and at least a venting slot 24 formed
in the shank portion 22 adjacent to the needle head portion 23 for
venting air outwardly through the needle hole 20 of the needle device
2.
The needle head portion 23 may be formed as elliptic shape having
a needle-head center 230 intersected by a transverse head axis 230a
and a conjugate head axis 230b perpendicular to the transverse head
axis 230a defined in the head portion 23 elliptically shaped, with
the conjugate head axis 230b of the needle head portion 23 aligned
with the needle axis 200 of the needle device 2 and normally parallel
to the syringe axis 100 of the syringe means 1 when the needle device
2 is normally secured on the syringe means 1.
The venting slot 24 formed in the shank portion 22 of the needle
device 2 is generally elongate shaped to have a first section of
a total length of the slot 24 positioned in the plug 13 and to have
a second section of the total length of the slot 24 positioned beyond
the plug surface 135 communicating the hollow bore portion 10 in
the syringe cylinder 11. Each first section and second section of
the total length of the slot 24 may be one half of the total slot
length, but not limited in this invention.
The plunger means 3 includes: a plunger 31 reciprocatively held
in the syringe cylinder 11 the annular groove 32 annularly recessed
in a front surface portion 310 of the plunger 31 having a longitudinal
section of elliptically shaped biasing socket to be operatively
obliquely engageable with the needle head portion 23 a guiding
port 33 formed in a front portion of the annular groove 32 converging
rearwardly for communicating the annular groove 32 for slidably
guiding the needle head portion 23 rearwardly through the guiding
port 33 to be engaged into the biasing socket of the annular groove
32 for biasing the needle portion 21 obliquely when retracting the
needle device within the hollow bore portion 10 in the syringe cylinder
11 a plunger rod 35 connected with the plunger 31 and protruding
rearwardly to have a plunger-rod handle 37 formed on a rear end
portion of the rod 35 for grasping the handle 37 for squeezing the
plunger 31 for injection use, and a plunger axis 300 longitudinally
existing in a central portion of the plunger 31 and the rod 35 aligned
with the syringe axis 100. The guiding port 33 includes a front
large opening 331 having a size generally equal to that of the needle
head portion 23 and a rear small opening 332 rearwardly contracted
from the large opening 331 and communicating the biasing socket
of the annular groove 32.
The biasing socket of the annular groove 32 of the plunger means
3 is formed as an elliptic shape having a socket center 320 intersected
by a transverse socket axis 320a and a conjugate socket axis 320b
perpendicular to the transverse socket axis 320a defined within
the biasing socket of the annular groove 32 with the conjugate socket
axis 320b normally deviated from the conjugate head axis 230b and
the needle axis 20 (which is parallel to the syringe axis 100 of
the syringe means 1 when the needle device 2 is inserted in the
tunnel 130) for an acute angle A defined between the conjugate socket
axis 320b and the needle axis 200 of the eccentrically mounted needle
device 2 when retracting the needle device 2 within the hollow bore
portion 10 in the syringe cylinder 11 after using the needle for
medical injection purpose as shown in FIGS. 5 3 with the socket
center 320 normally aligned with the needle-head center 230 of the
needle device 2 and normally aligned with the needle axis 200 when
the needle device is eccentrically secured on the syringe means
for intravenous injection (I.V.) purpose, whereby upon a squeezing
of the plunger 31 frontwardly by pushing the rod handle 37 frontwardly
to boost a liquid medicine 4 filled in the cylinder 11 for injection
use through the needle hole 20 the needle head portion 23 will
be engaged with the biasing socket of the annular groove 32 of the
plunger 31 when the plug surface 135 matching with the plunger front
surface 310 for "trans-planting" the needle head portion
23 into the biasing socket of the groove 32 of the plunger 31 (since
the plunger 31 is made flexible such as from rubber material, the
plunger can be compressed for a snug engagement of the needle portion
23 with the biasing socket of groove 32); and upon a retraction
of the plunger 31 the needle device 2 will be retracted into the
bore portion 10 of the syringe cylinder 11 and the needle-head portion
23 and the needle portion 21 will be biased with the acute angle
A since the conjugate socket axis 320b of the biasing socket 32
is already deviated from the needle axis 200 of the eccentrically
mounted needle device 2 with the acute angle A as aforementioned,
thereby preventing a re-protrusion of the needle portion 21 outwardly
from the syringe cylinder for preventing an injury or infectious
contamination to an environmental surroundings.
The liquid-repelling extension 15 concentrically formed in a rear
surface 135 of the front plug 13 inserted in a front portion of
the syringe cylinder 11 has the flat surface portion 151 recessed
in the liquid-repelling extension 15 and coplanar to the rear surface
135 of the front plug 13 for receiving the needle head portion 23
of the needle device 2 within the recessed flat surface portion
151 (FIG. 1), with the liquid-repelling extension 15 having a longitudinal
section of arcuate or semicircular shape and engageable with the
annular groove 32 recessed in the plunger 31 thereby squeezing
the liquid medicine outwardly as filled into the annular groove
32 when moving and pumping the plunger 31 towards the plug 13 for
almost finishing the injecton operation for saving any medicine
4 and preventing loss of medicine even a small volume filled in
the groove 32.
The liquid-repelling extension 15 has the longitudinal section
of arcuate shape to be slightly smaller than the biasing socket
of the annular groove 32 for an easy decoupling of the plunger 31
from the plug 13 when retracting the needle device 2 into the syringe
cylinder 11 (FIG. 2 to FIG. 3).
The plunger 31 may be formed with a recess 34 in a rear surface
of the plunger 31 to be engaged with a coupling member 36 formed
on a front end of the rod 35 for connecting the plunger 31 with
the rod 35.
As shown in FIG. 4 after retracting the needle 2 in the cylinder
11 a further apply of an external force for protruding the needle
portion 21 outwardly, the needle portion 21 as previously biased
in the cylinder 11 will be bent or even inserted into the plug 13
to be blocked by the syringe cylinder 11 to prevent its outward
protrusion.
Therefore, this invention is quite safe for preventing an unexpected
inadvertent protruding of an injection needle from the syringe after
being used, thereby beneficial for medical or hospital waste disposal
for enhancing environmental hygiene and human health. During the
injection operation, the needle 2 can be transferred to the plunger
31 and retracted into the cylinder 11 without being exposed to the
environment for absolute safety purpose. |