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Medical Patent Abstract
In a medical needle device having a shield for reduction of needlestick
injuries, a protrusion is formed on an outer peripheral surface
of a hub to which a needle is mounted, a height of the protrusion
being set so that the protrusion protrudes beyond an inner diameter
of a shield tube, and a gate groove is formed at an inner surface
of the shield tube to extend from a front end to the vicinity of
a rear end, dimensions of the gate groove being such that the protrusion
can fit in a front end portion of the gate groove. In a state where
the protrusion is exposed from the front end of the shield tube,
the hub can rotate with respect to the shield tube. At a rotational
position of the protrusion at which it does not face a front end
of the gate groove, a position of the hub is limited so as not to
move toward a rear end side of the shield tube due to engagement
of the protrusion with a front end face of the shield tube. At a
rotational position of the protrusion at which it face the front
end of the gate groove, the protrusion can slide into the gate groove,
whereby the hub can move so that a tip of the needle can be stored
in the shield tube. In the penetrating state of the needle that
enables the puncturing, the needle cannot move in the shield for
reduction of needlestick injuries and can rotate.
Medical Patent Claims
What is claimed is:
1. A medical needle device having a shield for reduction of needlestick
injuries, comprising: the shield for reduction of needlestick injuries
including a substantially cylindrical shield tube as a main body;
a hub inserted into the shield tube so that the hub is movable in
an axial direction and whose rear end portion can be connected to
an infusion tube; and a needle mounted to a front end portion of
the hub, wherein a tip of the needle can be stored in an inner bore
of the shield tube, wherein the hub has a protrusion at a portion
of an outer peripheral surface at a front end portion thereof, a
height of the protrusion being such that the protrusion protrudes
beyond an inner diameter of the shield tube, and a gate groove is
formed at an inner surface of the shield tube as a stripe shaped
recess so as not to pass entirely through the wall of the shield
tube and so as to extend from a distal end to the vicinity of a
rear end of the shield tube, the gate groove having dimensions such
that the protrusion at the front end portion of the hub can fit
in a front end portion of the gate groove, in a state where the
protrusion is exposed from the front end of the shield tube, the
hub can rotate around an axis of the shield tube, at a rotational
position of the protrusion at which it does not face a front end
of the gate groove, a position of the hub is limited so as not to
move toward a rear end side of the shield tube due to engagement
of the protrusion with a front end face of the shield tube, and
at a rotational position of the protrusion at which it faces the
front end of the gate groove, the protrusion can slide into the
gate groove.
2. The medical needle device having a shield for reduction of needlestick
injuries according to claim 1, wherein the shield tube has an engagement
hole that is formed adjacent to a rear end of the gate groove, a
depth of the gate groove being set so as to be shallower than the
height of the protrusion at a rear end portion of the gate groove,
and the protrusion can slide along the gate groove so as to engage
with the engagement hole.
3. The medical needle device having a shield for reduction of needlestick
injuries according to claim 1, wherein the protrusion is provided
at a position that does not correspond to a side of a blade surface
of the needle and its reverse side in a circumferential direction
of the hub.
4. The medical needle device having a shield for reduction of needlestick
injuries according to claim 1, wherein the protrusion is provided
at a position that corresponds to a side of a blade surface of the
needle in a circumferential direction of the hub.
5. The medical needle device having a shield for reduction of needlestick
injuries according to claim 1, further comprising: a latching strip
having flexibility, provided so as to extend from a side wall of
the shield tube; and a through hole provided in the shield tube
so as to correspond to a position of the latching strip, wherein
the latching strip has a protrusion protruding toward a side direction,
and when the latching strip is wrapped around the shield tube, the
protrusion is inserted into the through hole so as to limit movement
of the hub in the axial direction within the shield tube.
6. The medical needle device having a shield for reduction of needlestick
injuries according to claim 5, wherein the latching strip has a
mechanism for holding the latching strip, functioning so as to hold
the wrapped state of the latching strip around the shield tube.
7. The medical needle device having a shield for reduction of needlestick
injuries according to claim 1, the shield for reduction of needlestick
injuries is a winged shield that further comprises a pair of wings
coupled near the front end of the shield tube.
8. The medical needle device having a shield for reduction of needlestick
injuries according to claim 7, wherein each of the wings has a wing
protrusion formed so as to protrude from a wing surface, the shield
tube has through holes formed on side portions of a cylindrical
wall so that the wing protrusions can be inserted in the respective
through holes, and by superimposing both of the wings on the shield
tube along a side surface of the shield tube, each wing protrusion
can pass through the through hole so as to be inserted into the
inner bore of the shield tube, so that each wing protrusion prevents
the hub from moving in the axial direction within the shield tube,
and so that the hub can be held with respect to the shield tube
while keeping a state in which the needle protrudes from the front
end of the shield tube by a predetermined length.
Medical Patent Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to medical needle devices, and more
particularly relates to medical needle devices having a shield for
the reduction of needlestick injuries, in which a used needle can
be stored safely.
2. Related Background Art
Conventionally, contamination and infections due to needlestick
injuries with injection needles or puncture needles have been a
problem in medical facilities. In particular, recently, as hepatitis
B, hepatitis C, HIV (human immunodeficiency virus) and the like
have received widespread attention, there is a strong demand for
means that actively reduce such needlestick injuries.
As a means for preventing such needlestick injuries, a configuration
in which a cylindrical shield is provided so that the shield can
slide with respect to the injection needle is known. That is, depending
on the sliding position of the shield, the injection needle is either
exposed or it is contained in the shield. When disposing of a used
injection needle or a used puncture needle, a needle is slid into
the shield so as to be contained therein.
Injection needle devices described in JP H6(1994)-7861B, JP H5(1993)-300942A
and U.S. Pat. No. 4,170,993 are known as examples of such configurations.
These injection needle devices are a winged injection needle device
that is used widely in a procedure such as a liquid infusion, a
blood transfusion, extracorporeal blood circulation, or the like.
In the winged injection needle device, the wings are attached to
the outer peripheral surface of a slidable cylindrical shield, and
the wings slide together with the shield on the outer side of the
injection needle. In order to prevent needlestick injuries after
use of the injection needle, the tip of the injection needle can
be covered with the shield by sliding it.
In the course of using such an injection needle device having the
cylindrical shield, a mechanism is necessary for limiting the position
of the injection needle relative to the shield so as to maintain
a predetermined state with the needle protruding from the shield.
Especially, during the puncturing action, the injection needle should
be held so as not to be pushed into the shield. In addition, after
the puncturing action, in order to retain the puncturing state of
the injection needle, the injection needle might be required to
be held at a predetermined position relative to the shield. This
is because, even when the shield is fixed to the punctured portion
of the patient for preventing the injection needle from leaving
the retained state, if the injection needle is easily moved within
the shield, there is the risk that the injection needle comes off
the punctured portion of the patient. Each injection needle device
described in JP H6(1994)-7861B, JP H5-300942 A or U.S. Pat. No.
4,170,993 has a configuration for holding a predetermined state
of an injection needle relative to a shield.
Furthermore, at the time of storing the injection needle in the
shield, it is desirable that the injection needle can slide easily
with respect to the shield. In the case of the configuration described
in JP H6-7861B, however, in order to store the injection needle
in the shield, the injection needle has to be retracted in the shield
against a holding force for holding the injection needle with respect
to the shield while the holding force is still applied thereto.
In the case of the configuration described in JP H5-300942 A, at
the time of storing the injection needle in the shield, the force
for holding the injection needle can be weakened. Due to its configuration,
however, it is difficult to weaken sufficiently the force applied
when the injection needle is stored in the shield while ensuring
the sufficiently large force for holding the injection needle with
respect to the shield. According to the configuration described
in U.S. Pat. No. 4,170,993, such conditions can be satisfied.
In the injection needle device described in U.S. Pat. No. 4,170,993,
however, a configuration for holding the injection needle forms
an obstacle, which makes it difficult for the injection needle to
rotate with respect to the shield in the usage state in which the
injection needle protrudes from the shield.
In order to adapt to various operations suitably, it is desirable
that, in the usage state in which the injection needle protrudes
from the shield, the injection needle can rotate with respect to
the shield. For instance, in order to make an angle of a blade surface
of the needle after puncturing different from that during the puncturing,
the injection needle has to be rotated. Also, in both of the configurations
described in JP H6(1994)-7861B and JP H5(1993)-300942A, it is difficult
to make the injection needle rotatable with respect to the shield
in the usage state in which the injection needle protrudes from
the shield.
Although the above problems are described referring to the example
of the winged injection needle device, these problems arise commonly
also in injection needle devices without wings.
SUMMARY OF THE INVENTION
Therefore, with the foregoing in mind, it is an object of the present
invention to provide a medical needle device having a shield for
the reduction of needlestick injuries, capable of limiting the position
of a needle so as not to move in a shield from a usage state in
which the needle protrudes from the shield, and capable of allowing
the needle to rotate with respect to the shield in that state as
well.
A medical needle device having a shield for reduction of needlestick
injuries according to the present invention includes: the shield
for reduction of needlestick injuries including a substantially
cylindrical shield tube as a main body; a hub inserted into the
shield tube so that the hub is movable in an axial direction and
whose rear end portion can be connected to an infusion tube; and
a needle mounted to a front end portion of the hub. A tip of the
needle can be stored in an inner bore of the shield tube. The hub
has a protrusion at a portion of an outer peripheral surface at
a front end portion thereof, a height of the protrusion being such
that the protrusion protrudes beyond an inner diameter of the shield
tube. A gate groove is formed at an inner surface of the shield
tube so as to extend from a front end to the vicinity of a rear
end of the shield tube, the gate groove having dimensions such that
the protrusion at the front end portion of the hub can fit in a
front end portion of the gate groove. In a state where the protrusion
is exposed from the front end of the shield tube, the hub can rotate
with respect to the shield tube. At a rotational position of the
protrusion at which it does not face a front end of the gate groove,
a position of the hub is limited so as not to move toward a rear
end side of the shield tube due to engagement of the protrusion
with a front end face of the shield tube. At a rotational position
of the protrusion at which it faces the front end of the gate groove,
the protrusion can slide into the gate groove.
With this configuration, in the state of a needle protruding from
the shield, the engagement of the protrusion with the front end
face of the shield tube allows the needle to be held so as not to
move in the shield. In addition, in that state, the needle can rotate
with respect to the shield.
In the above configuration, preferably, the shield tube has an
engagement hole that is formed adjacent to a rear end of the gate
groove, a depth of the gate groove being set so as to be shallower
than the height of the protrusion at a rear end portion of the gate
groove, and the protrusion can slide along the gate groove so as
to engage with the engagement hole. With this configuration, when
the needle is stored in the shield tube, the needle can be held
with respect to the shield tube securely.
The protrusion may be provided at a position that does not correspond
to a side of a blade surface of the needle and its reverse side
in a circumferential direction of the hub. With this configuration,
when the needle is held so as not to move in the shield, the needle
can be set in a state convenient for the puncturing action. As a
result, an unexpected accident in which the needle retracts in the
shield can be prevented.
The protrusion may be provided at a position that corresponds to
a side of a blade surface of the needle in a circumferential direction
of the hub. In this case, when the protrusion engages with the gate
groove so as to make it impossible for the needle to rotate with
respect to the shield, with a blade surface facing upwards, the
protrusion is prevented from contacting with the punctured portion
of the patient. Therefore, a state suitable for the puncturing can
be obtained securely.
Preferably, the above medical needle device having a shield for
reduction of needlestick injuries further includes: a latching strip
having flexibility, provided so as to extend from a side wall of
the shield tube; and a through hole provided in the shield tube
so as to correspond to a position of the latching strip. The latching
strip has a protrusion protruding toward a side direction, and when
the latching strip is wrapped around the shield tube, the protrusion
is inserted into the through hole so as to limit movement of the
hub in the axial direction within the shield tube. This configuration
enables the hub to be held in a predetermined state with respect
to the shield tube.
In addition, it is preferable that the latching strip has a mechanism
for holding the latching strip, functioning so as to hold the wrapped
state of the latching strip around the shield tube.
The above-mentioned shield for reducing needlestick injuries may
be a winged shield that further includes a pair of wings coupled
near the front end of the shield tube.
Preferably, each of the wings has a wing protrusion formed so as
to protrude from a wing surface, and the shield tube has through
holes formed on side portions of a cylindrical wall so that wing
protrusions can be inserted in the respective through holes. By
superimposing both of the wings on the shield tube along a side
surface of the shield tube, each wing protrusion can pass through
the through hole so as to be inserted into the inner bore of the
shield tube, so that each wing protrusion prevents the hub from
moving in the axial direction within the shield tube, and so that
the hub can be held with respect to the shield tube while keeping
a state in which the needle protrudes from the front end of the
shield tube by a predetermined length.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a medical needle device according to Embodiment
1 of the present invention.
FIG. 2 is a side view of the same medical needle device from a
left side of FIG. 1.
FIG. 3A is a cross-sectional view taken along the line A-A of FIG.
1.
FIG. 3B is a cross-sectional view showing a state after a storing
action is conducted on the device in the state of FIG. 3A.
FIG. 4A is a plan view showing an operation of the medical needle
device of Embodiment 1.
FIG. 4B shows a cross-section of the state of FIG. 4A.
FIG. 5 is a cross-sectional view showing another embodiment of
the medical needle device according to Embodiment 1.
FIG. 6A is a plan view showing an improved example of the medical
needle device of FIG. 1.
FIG. 6B is a cross-sectional view taken along the line B-B of FIG.
6A.
FIG. 7A is a plan view showing an operation of the medical needle
device of FIG. 6A.
FIG. 7B is a cross-sectional view taken along the line C-C of FIG.
7A.
FIG. 7C is a cross-sectional view taken along the line D-D of FIG.
7A.
FIG. 8 is a plan view of a winged medical needle device according
to Embodiment 2 of the present invention.
FIG. 9 is a side view of the same medical needle device from a
left side of FIG. 8.
FIG. 10 is a cross-sectional view showing a planar shape of the
same medical needle device.
FIG. 11A is a cross-sectional view taken along the line E-E of
FIG. 8.
FIG. 11B is a cross-sectional view showing an operation, following
the state of FIG. 11A.
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
FIG. 1 is a plan view of a medical needle device according to Embodiment
1 of the present invention, and FIG. 2 is a side view of the medical
needle device from a left side of FIG. 1. FIG. 3A is a cross-sectional
view taken along the line A-A of FIG. 1. FIG. 3B is a cross-sectional
view showing a state after a storing action is conducted on the
device in the state of FIG. 3A.
Reference numeral 1 denotes a needle, which is fixed to a front
end portion of a hub 2 made of resin. A tube 3 is connected to a
rear end portion of the hub 2. Reference numeral 4 denotes a shield,
including as a main body a shield tube 4a made of resin and having
a substantially cylindrical shape. The hub 2 has a length such that
a front end portion and a rear end portion thereof can protrude
from the shield tube 4a when the hub 2 is inserted into an inner
bore of the shield tube 4a. An outer diameter of the hub 2 has a
size such that a slight gap can be formed between the hub 2 and
an inner wall of the shield tube 4a so as to allow the rotation
of the hub 2 with respect to the shield tube 4a and the movement
of the hub 2 in an axial direction.
On the front end portion of the hub 2 that is exposed from a front
end of the shield tube 4a, a protrusion 11 is formed at a portion
of its outer peripheral surface. A height of the protrusion 11 from
the outer surface of the hub 2 is, as shown in FIG. 2, set so that
the protrusion 11 protrudes beyond the inner diameter of the shield
tube 4a. On an outer surface of the shield tube 4a, a ridge portion
12 is formed, as shown in FIG. 1, so as to extend in the axial direction
from the front end to the vicinity of a rear end of the shield tube
4a. On an inner wall of the ridge portion 12, a gate groove 12a
is formed to extend in the axial direction from the front end to
the vicinity of the rear end of the shield tube 4a. The gate groove
12a has dimensions such that the protrusion 11 can enter through
a front end portion of the gate groove 12a. An engagement hole 13
is formed adjacent to a rear end of the gate groove 12a so as to
penetrate the wall of the shield tube 4a. The engagement hole 13
has dimensions so as to allow the engagement with the protrusion
11. The ridge portion 12 is not necessarily provided for forming
the gate groove 12a. If the shield tube 4a is thick enough, the
gate groove 12a may be formed directly at the inner wall of the
shield tube 4a.
As is evident from FIG. 3A, the protrusion 11 can enter through
the front end of the gate groove 12a so as to slide along the gate
groove 12a. Furthermore, as shown in FIG. 3B, the protrusion 11
can pass through the rear end of the gate groove 12a so as to engage
with the engagement hole 13. In this state, a tip of the needle
1 is stored in the inner bore of the shield tube 4a.
The gate groove 12a is tilted so that a depth from an inner wall
surface of the shield tube 4a becomes shallower toward the rear
end and so that the depth at the rear end becomes smaller than the
height of the protrusion 11. Therefore, in the course of sliding
of the protrusion 11 along the gate groove 12a, a top surface of
the protrusion 11 contacts with a bottom surface of the gate groove
12a by an increasing force with increasing proximity to the rear
end. Thus, when the protrusion 11 passes through the rear end of
the gate groove 12a, the protrusion 11 is elastically deformed to
be compressed in the height direction. As a result of the engagement
with the engagement hole 13, the compressive pressure is released,
so that the height of the protrusion recovers. In this state, the
contact of a front end face of the protrusion 11 with a rear end
face of the ridge portion 12 makes it impossible for the protrusion
11 to move to the front end side, i.e., to move backward. At the
same time, the contact of a rear end face of the protrusion 11 with
a rear end face of the engagement hole 13 prevents the protrusion
11 from moving toward the rear end side. In this way, the engagement
of the protrusion 11 with the engagement hole 13 can provide a function
for locking the hub 2 with respect to the shield tube 4a. As a result,
the state of the needle 1 being stored in the shield tube 4a can
be kept, so that a state for avoiding needlestick injuries can be
provided. The tile of the gate groove 12a may be provided at the
total length or at the rear side portion.
As is evident from these configurations, when the protrusion 11
shown in FIG. 1 is exposed from the front end of the shield tube
4a, the hub 2 can rotate with respect to the shield tube 4a. With
this configuration, as shown in FIG. 4A, the protrusion 11 can have
a state of protruding in the side direction of the shield tube 4a.
FIG. 4B shows a cross-section of the state of FIG. 4A. Since the
hub 2 can rotate with respect to the shield tube 4a, a rotational
position of a blade surface 1a of the needle 1 can be adjusted freely
relative to the shield 4, so as to be adaptable to various operations
to be conducted after the puncturing action.
In the state of FIG. 4A, the protrusion 11 does not face the front
end of the gate groove 12a. At this rotational position, the engagement
of the rear end face of the protrusion 11 with the front end face
of the shield tube 4a prevents the hub 2 from moving toward the
rear end side. Therefore, during the puncturing action, for example,
by adjusting the rotational position of the protrusion 11 to such
a position, a state of the needle 1 can be held so as to protrude
from the shield tube 4a and so as not to be pushed into the shield
tube 4a.
As stated above, in the usage position in which the needle 1 protrudes
from the front end of the shield tube 4a by a predetermined length,
the engagement of the protrusion 11 with the front end face of the
shield tube 4a limits the position of the hub 2 with the needle
1 attached thereto, within the shield tube 4a. In addition, the
contact of an end face of the tube 3 with the rear end of the shield
tube 4a prevents the hub 2 from further moving in the direction
toward the front end of the shield tube 4a. With this configuration,
the position of the needle 1 can be limited so as not to protrude
from the shield tube 4a by the predetermined length or more. As
a result of these configurations, a function for holding the hub
2 at the usage position can be obtained.
To dispose of the medical needle device after usage, the rotational
position of the protrusion 11 is adjusted so as to face the gate
groove 12a, whereby the hub 2 can move easily toward the rear end
side of the shield tube 4a and, as shown in FIG. 3B, can be retained
in that position.
The positional relationship between the protrusion 11 and the blade
surface 1a of the needle 1 in the circumferential direction of the
hub 2 may be set depending on an intended use. For instance, in
FIG. 4A, the protrusion 11 is provided at a position that forms
an angle of 90.degree. with the blade surface 1a of the needle 1
in the circumferential direction of the hub 2. In this way, the
protrusion 11 can be provided at the position that does not correspond
to a side of the blade surface 1a and its reverse side, whereby
the needle 1 can be set in a state convenient for the puncturing
action while the needle 1 can be kept so as not to move in the shield
tube 4a. As a result, unexpected accidents such as the needle 1
being retracted in the shield tube 4a from the puncturing state
can be prevented. Alternatively, as shown in FIG. 5, there may be
a case where the protrusion 11 at the position that corresponds
to the blade surface 1a is convenient. In such a case, by engaging
the protrusion 11 with the gate groove 12a so that the needle 1
cannot rotate with respect to the shield tube 4a, the protrusion
11 does not contact with the punctured portion of the patient when
the blade surface 1a faces upward. Therefore, a suitable state for
the puncturing can be obtained with reliability.
The above-described embodiment exemplifies the case where the device
includes one protrusion 11 and one gate groove 12. However, the
device can include a combination of one or two protrusions 11 and
two gate grooves 12.
In addition to the above-described basic configuration, as shown
in FIG. 6A, a holding mechanism can be provided additionally for
latching the hub 2 with respect to the shield tube 4a. FIG. 6B is
a cross-sectional view of the shield tube 4a taken along the line
B-B of FIG. 6A. Reference numeral 14 denotes a latching strip that
makes up the holding mechanism. The latching strip is provided to
extend from a side wall of the shield tube 4a and has flexibility.
The latching strip 14, as shown in FIG. 6B, has a substantially
arc shape, in which a protrusion 14a and a grasping rib 14b are
formed. At a front end portion of the latching strip 14, an engagement
hole 14c is formed. On a side wall of the shield tube 4a, a fixing
protrusion 15 is formed on the opposite side of the latching strip
14.
A function of the latching strip 14 will be described below, with
reference to FIGS. 7A to C. FIG. 7A shows a state where the hub
2 is retracted in the shield tube 4a to some extent from the state
of FIG. 6A. FIG. 7B is a cross-sectional view taken along the line
C-C of FIG. 7A. FIG. 7C is a cross-sectional view of the shield
tube 4a taken along the line D-D of FIG. 7A. As shown by FIG. 7B
only, an annular groove 2a is formed on an outer surface of the
hub 2. In the state shown in FIGS. 7A to C, a position of the annular
groove 2a coincides with the position of the engagement hole 13.
As shown in these drawings, the latching strip 14 can be wrapped
around the shield tube 4a by virtue of its flexibility. As a result
of the wrapping of the latching strip 14 around the shield tube
4a, the protrusion 14a protrudes into the inner bore of the shield
tube 4a through the engagement hole 13. Thereby, a front end portion
of the protrusion 14a engages with the annular groove 2a, thus obtaining
a function of latching the hub 2 with respect to the shield tube
4a. Note here that the annular groove 2a is not necessarily required.
That is to say, by contacting the front end of the protrusion 14a
with the outer surface of the hub 2 so as to apply pressure thereto,
the hub 2 can be held by the frictional force.
Furthermore, in the above-mentioned state, as clearly shown by
FIG. 7C, the engagement hole 14c at the front end portion of the
latching strip 14 engages with the fixing protrusion 15. Thereby,
the wrapped state of the latching strip 14 around the shield tube
4a can be held.
The above-stated holding mechanism is provided for the following
reasons: that is, in the state of FIG. 6A, the rotational position
of the protrusion 11 coincides with the gate groove 12, so that
the hub 2 can move toward the rear end side of the shield tube 4a.
Meanwhile, there is a case where the needle 1 should be held at
such an angle, and therefore, in order to latch the hub 2 with respect
to the shield tube 4a in this state so as to prevent the needle
1 from retracting in the shield tube 4a, the holding mechanism is
provided. Alternatively, there is another case where the hub 2 should
be latched to the shield tube 4a in the state shown in FIG. 7A.
This is because, in this state, the protrusion 11 is inside the
gate groove 12a, and therefore the rotation of the hub 2 and the
needle 1 can be limited.
Note here that, a configuration for engaging the hub 2 with the
protrusion 14a of the latching strip 14 is not limited to the above
configuration that uses the engagement hole 13. Instead, the latching
strip 14 may be provided at a different position from the engagement
hole 13 and a through hole may be provided separately so as to allow
the protrusion 14a to protrude into the shield tube 4a.
Embodiment 2
FIG. 8 is a plan view of a medical needle device according to Embodiment
2 of the present invention, and FIG. 9 is a side view of the medical
needle device from a left side of FIG. 8. FIG. 10 is a cross-sectional
view showing a planar shape of the same device. This embodiment
relates to a configuration having a winged shield, in which left
and right wings are given to the shield tube 4a of Embodiment 1.
The basic configurations of the shield tube and the hub are the
same as in Embodiment 1. Therefore, the elements that are the same
as those in Embodiment 1 are given the same reference numerals for
their explanations.
Reference numeral 1 denotes a needle, which is fixed to a front
end portion of a hub 2 made of resin. A tube 3 is connected to a
rear end portion of the hub 2. Reference numeral 24 denotes a winged
shield, including a shield tube 24a made of resin and having a substantially
cylindrical shape, and left and right wings 5 and 6. The hub 2 has
a length such that a front end portion and a rear end portion thereof
can protrude from the shield tube 4a when the hub 2 is inserted
into an inner bore of the shield tube 24a. An outer diameter of
the hub 2 has a size such that a slight gap can be formed between
the hub 2 and an inner wall of the shield tube 24a so as to allow
the rotation of the hub 2 with respect to the shield tube 24a and
the movement of the hub 2 in an axial direction.
The left and right wings 5 and 6 are provided at a front end portion
of the shield tube 24a, that is, at an end portion of the shield
tube 24a on a side from which the needle 1 protrudes. The wings
5 and 6 are coupled to both side portions of an outer peripheral
surface of the shield tube 24a, respectively, and may have a symmetric
shape with respect to the axis of the shield tube 24a in the center.
At base regions of the wings 5 and 6, wing protrusions 7 and 8 are
formed respectively. On left and right side walls of the shield
tube 24a, through holes 9 and 10 are formed so as to correspond
to the wing protrusions 7 and 8, respectively.
On the front end portion of the hub 2 that is exposed from a front
end of the shield tube 24a, a protrusion 11 is formed at a portion
of its outer peripheral surface. On an outer surface of the shield
tube 24a, a ridge portion 12 is formed, and on an inner wall of
the ridge portion 12, a gate groove 12a is formed. The configurations
and effects of the protrusion 11, the gate groove 12a and the like
are substantially the same as in Embodiment 1.
The protrusion 11 is provided at a position that does not correspond
to a side of a blade surface 1a of the needle 1 and its reverse
side in the circumferential direction of the hub 2. Therefore, this
configuration can prevent the protrusion 11 from facing the gate
groove 12a in a state where the blade surface 1a faces toward a
direction perpendicular to the wings 5 and 6. Normally, at the time
of puncturing, the blade surface 1a is set so as to face toward
the direction perpendicular to the wings 5 and 6, and therefore
this configuration can prevent the needle 1 from being pushed into
the shield tube 24a during the puncturing.
FIGS. 11A and 11B show the function of the wing protrusions 7 and
8 provided on the wings 5 and 6. FIGS. 11A and 11B are cross-sectional
views taken along E-E of FIG. 8. The action utilizing the wings
5 and 6 is carried out in the course of puncturing.
From the state shown in FIG. 11A, the wings 5 and 6 are lifted
upwards along the outer surface of the shield tube 24a, so that,
as shown in FIG. 11B, the wing protrusions 7 and 8 are inserted
into the through holes 9 and 10, extend through the wall of the
shield tube 24a, and protrude into the inner bore. As a result,
the front end portions of the wing protrusions 7 and 8 contact with
the outer surface of the hub 2. By the frictional force resulting
from the pressure of the contact, the hub 2, and therefore the needle
1, can be held with respect to the winged shield 24. Therefore,
the puncturing action can be carried out while the needle 1 can
be held securely. Also, by pressing the two wings 5 and 6 together
with fingers, a sufficient compressive force can be applied to the
wing protrusions 7 and 8 so as to hold the hub 2 firmly.
Note here that it is preferable that a bottom portion of the outer
surface of the shield tube 24a is made flat, so that it can be positioned
securely on the patient's skin. In the drawings, the inner bore
of the shield tube 24a is circular, but it is also possible that
the upper side of the inner bore is provided with a curved surface
corresponding to the outer surface shape of the hub 2, and that
a bottom portion of the inner bore surface is flat.
According to the medical needle device having a shield for the
reduction of needlestick injuries, in the state of the needle protruding
from the shield so as to enable the puncturing action, the needle
can be held so as not to move in the shield. Moreover, in that state,
the needle can rotate with respect to the shield.
The invention may be embodied in other forms without departing
from the spirit or essential characteristics thereof. The embodiments
disclosed in this application are to be considered in all respects
as illustrative and not limiting. The scope of the invention is
indicated by the appended claims rather than by the foregoing description,
and all changes which come within the meaning and range of equivalency
of the claims are intended to be embraced therein.
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