Safety syringe abstract
A safety syringe includes: a hollow needle secured in a front portion
of the syringe for injection use having a needle head portion formed
on a rear portion of the needle, and a plunger slidably held in
the syringe for boosting a liquid medicine in the syringe to be
injected into a patient through the hollow needle having a biasing
socket recessed in a front portion of the plunger 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 preventing its injury or infectious contamination to
the surroundings.
Safety syringe claims
I claim:
1. A safety syringe comprising: a syringe means for filling liquid
medicine therein; a needle device secured in a front portion of
the syringe means for injection use having a needle head portion
formed on a rear portion of the needle device, and a plunger means
slidably held in the syringe means for boosting the liquid medicine
in the syringe means to be injected into a patient through the needle
device having a biasing socket recessed in a front portion of the
plunger means engageable with the needle head portion of said needle
device for biasing said needle device obliquely within the syringe
means when retracting the plunger means and the needle device into
the syringe means, thereby preventing an outward protruding of a
retracted needle device for preventing injury or infectious contamination
by the needle device to environmental surroundings;
said syringe means including: a syringe cylinder having a hollow
bore portion defined in the syringe cylinder and a syringe axis
longitudinally existing in a central portion of the syringe cylinder,
a sleeve portion formed in a front portion of the cylinder contracted
from the cylinder having a needle port formed in a central opening
of the sleeve, a front plug having a plug tip portion embedded in
the sleeve portion and a plug shoulder portion embedded in a front
portion of the cylinder connected with the tip portion and a tunnel
formed in the plug communicating the needle port for inserting the
needle device in the tunnel and in the needle port, and a syringe
handle formed on a rear end portion of the cylinder;
said needle device including: a needle portion, a shank portion
connected with the needle portion having a plurality of needle rings
circumferentially formed on the shank portion for firmly engaging
the shank portion in the tunnel of the syringe means for protruding
the needle portion beyond the needle port of the syringe means,
the needle head portion formed on a rear portion of the shank portion
protruding rearwardly beyond a plug surface formed on a rear end
surface of the plug to be engageable with the biasing socket of
the plunger means, a needle hole formed through the needle portion,
the shank portion and the needle head portion for passing liquid
medicine therethrough for injection use, a needle axis longitudinally
existing in a central portion of the needle device normally aligned
with the syringe axis, and at least a venting slot formed in the
shank portion adjacent to the needle head portion for venting air
outwardly through the needle hole of the needle device;
and said plunger means including: a plunger reciprocatively held
in the syringe cylinder, the biasing socket recessed in a front
end portion of the plunger operatively obliquely engageable with
the needle head portion, a guiding port formed in a front portion
of the socket converging rearwardly for communicating the socket
for slidably guiding the needle head portion rearwardly through
the guiding port to be engaged into the socket for biasing the needle
portion obliquely when retracting the needle device within the hollow
bore portion in the syringe cylinder, a plunger rod connected with
the plunger and protruding rearwardly to have a plunger-rod handle
formed on a rear end portion of the rod for grasping the handle
for squeezing the plunger for injection use, and a plunger axis
longitudinally existing in a central portion of the plunger and
the rod.
2. A safety syringe according to claim 1 wherein said needle head
portion is formed as elliptic shape having a needle-head center
intersected by a transverse head axis and a conjugate head axis
perpendicular to the transverse head axis defined in the needle
head portion elliptically shaped, with the conjugate head axis of
the needle head portion aligned with the needle axis of the needle
device and normally aligned with the syringe axis of the syringe
means when the needle device is normally secured on the syringe
means.
3. A safety syringe according to claim 1 wherein said venting
slot formed in the shank portion of the needle device is generally
elongate shaped to have a first section of a total length of the
slot positioned in the plug and to have a second section of the
total length of the slot positioned beyond the plug surface of said
plug communicating the hollow bore portion in the syringe cylinder.
4. A safety syringe according to claim 1 wherein said guiding
port of said plunger means includes a front large opening having
a size generally equal to that of said needle head portion, and
a rear small opening contracted from said front large opening having
a size small than that of said needle head portion and communicating
the biasing socket.
5. A safety syringe according to claim 1 wherein said biasing
socket of the plunger means is formed as an elliptic shape having
a socket center intersected by a transverse socket axis and a conjugate
socket axis perpendicular to the transverse socket axis defined
within the socket, with the conjugate socket axis normally deviated
from the conjugate head axis and the syringe axis of the syringe
means for an acute angle defined between the conjugate socket axis
and the syringe axis when retracting the needle device within the
hollow bore portion in the syringe cylinder after using the needle
for medical injection purpose, with the socket center normally aligned
with the needle-head center of the needle device and normally aligned
with the syringe axis when the needle device is normally secured
on the syringe means, whereby upon a squeezing of the plunger frontwardly
by pushing the rod handle frontwardly to boost a liquid medicine
in the cylinder for injection use, the needle head portion will
be engaged with the socket of the plunger; and upon a retraction
of the plunger, the needle device will be retracted into the bore
portion of the syringe cylinder and the needle-head portion and
the needle portion will be biased with the acute angle from the
syringe axis for preventing a reprotrusion of the needle portion
outwardly from the syringe cylinder for preventing an injury and
infectious contamination to an environmental surroundings.
Safety syringe description
BACKGROUND OF THE INVENTION
A conventional syringe after being used for medical injection purpose
will be treated for waste disposal. If the injection needle mounted
on the syringe is protruded outwardly, it may cause infectious contamination
or pollution, hazardous to environmental protection and human health.
Even some improvements had been made to automatically retract the
injection needle into the syringe body to prevent injury or infectious
contamination to someone, the retracted needle as spring tensioned
may still be inadvertently protruded outwardly by an external force
or protruded downwardly when pendently held or when disposed in
a garbage yard for an accidentally protruding of the needle to cause
injury to the others.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a syringe of
which a needle may be biased after being retracted into the syringe
to prevent a re-protrusion of the needle outwardly from the syringe
to prevent injury or infectious contamination to the surroundings.
According to the invention, there is provided a safety syringe
including: a hollow needle secured in a front portion of the syringe
for injection use having a needle head portion formed on a rear
portion of the needle, and a plunger slidably held in the syringe
for boosting a liquid medicine in the syringe to be injected into
a patient through the hollow needle having a biasing socket recessed
in a front portion of the plunger 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 preventing
its injury or infectious contamination to the surroundings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration showing the present invention before
using.
FIG. 2 is a perspective view of a needle device of the present
invention.
FIG. 3 is an illustration showing a needle intended to be coupled
with a plunger of the present invention.
FIG. 3A is a partial enlarged illustration of the needle head portion
with the socket of this invention.
FIG. 4 shows a biased needle retracted in a syringe in accordance
with the present invention.
FIG. 5 shows another preferred embodiment of the present invention.
DETAILED DESCRIPTION
As shown in FIGS. 1-4 the present invention comprises: a syringe
means 1 a needle device 2 mounted in a front portion of the syringe
means 1 and a plunger means 3 slidably held in the syringe means
1.
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 a front portion of the
cylinder 11 contracted from the cylinder 11 having a needle port
121 formed in a central 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 and a syringe handle 14 formed
on a rear end portion of the cylinder 11.
The plug 13 has a plurality of packing rings 132 134 circumferentially
formed on the tip portion 131 and the shoulder portion 133 of the
plug 13 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 shank 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
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 therethrough for injection use, a needle
axis 200 longitudinally existing in a central portion of the needle
device 2 normally aligned with the syringe axis 100 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 aligned
with 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 biasing socket 32 recessed in a
front end portion of the plunger 31 operatively obliquely engageable
with the needle head portion 23 a guiding port 33 formed in a front
portion of the socket 32 converging rearwardly for communicating
the socket 32 for slidably guiding the needle head portion 23 rearwardly
through the guiding port 33 to be engaged into the socket 32 for
biasing the needle portion 21 obliquely when retracting the needle
device 2 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.
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 contracted from the large opening 331 and
communicating the socket 32.
The biasing socket 32 of the plunger means 3 may be 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 socket 32
with the conjugate socket axis 320b normally deviated from the conjugate
head axis 230b and the syringe axis 100 of the syringe means 1 for
an acute angle A defined between the conjugate socket axis 320b
and the syringe axis 100 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. 4 3A,
with the socket center 320 normally aligned with the needle-head
center 230 of the needle device 2 and normally aligned with the
syringe axis 100 when the needle device is normally secured on the
syringe means, whereby upon a squeezing of the plunger 31 frontwardly
by pushing the rod handle 37 frontwardly F (FIG. 1) to boost a liquid
medicine (not shown) filled in the cylinder 11 for injection use
through the needle hole 20 the needle head portion 23 will be engaged
with the socket 32 of the plunger 31 when the plug surface 135 matching
with a plunger front surface 310 for "trans-planting"
the needle head portion 23 into the socket 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 socket 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 syringe axis 100 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 plunger 31 may be formed with a plurality of annular rings
311 for resiliently retaining the plunger 31 in the syringe cylinder
11 for smoothly performing the injection operation.
Whenever injecting the needle 2 into a patient's skin, a counter
force acting backward by the patient may be overcome by the needle
rings 221 and the plunger 31 frictionally held in the syringe cylinder
11 thereby stabilizing the needle 2 for its injecting operation.
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
to a side corner in the cylinder 11 will be bent (numeral 21b) to
prevent its outward protrusion.
Therefore, this invention is quite safe for preventing an unexpected
inadvertent protruding of an injection needle from the syring after
being used, thereby beneficial for medical or hospital waste disposal
for enhancing environmental hygiene and human health.
As shown in FIG. 5 the matching surfaces 135a, 310a of the plug
13 and the plunger 31 may be slightly tapered frontwardly to smoothly
boosting a liquid medicine 4 frontwardly for an efficient injection
purpose.
As shown in FIG. 3A, the two transverse axes 230a, 320a of the
needle head portion 23 and the socket 32 also define an acute angle
A1 equal to the acute angle A of the biased angle of the retracted
needle 2 as shown in FIG. 4 since A1+B=90.degree., A+B=90.degree.,
so that A1=A as illustrated in FIG. 3A. |