SERINGUE

SYRINGE

Abrégé français

Une seringue comprend un corps tubulaire (11) fermé à une extrémité (12) et ouvert à l'autre (13), un piston (14) reçu dans le corps (11) pour définir une chambre (16) de volume variable et un support (24) d'aiguille, conçu pour recevoir et soutenir une aiguille creuse, et monté sur la paroi du corps (11) ou se logeant dans celle-ci, ce support pouvant se déplacer dans une direction généralement parallèle à l'axe principal du corps (11), entre une position initiale dans laquelle l'aiguille s'étend à partir d'une extrémité du corps (11) et l'intérieur de l'aiguille communique avec la chambre (16), et une seconde position dans laquelle l'extrémité externe de l'aiguille est escamotée. Ce support (24) d'aiguille comporte un élément en saillie (28) qui vient sélectivement en appui sur la paroi du corps (11) dans les première et seconde positions afin d'être retenu dans lesdites positions et qui passe à travers ladite paroi, dans la seconde position, pour s'accoupler au piston (14) et prévenir tout mouvement axial du support (24) d'aiguille aussi bien que du piston (14) par rapport au corps (11).

Abrégé anglais

A syringe comprising a tubular body (11) closed at one end (12) and open at
the other end (13), a plunger (14) receivable in the body
(11) to define a chamber (16) of variable volume, a needle support (24)
adapted to support and accommodate a hollow needle, said needle
support (24) being supported from or in the wall of the body (11) and being
movable in a direction substantially parallel to the main axis
of the body (11) between a first position at which the needle extends from the
one end of the body (11) and the interior of the needle is
in communication with the chamber (16), and a second position at which the
outer end of the needle is in a retracted position, said needle
support (24) having a protrusion (28) which is selectively engageable with the
wall of the body (11) at the first and second positions to be
able to be retained at said positions and receivable through the wall of the
body (11) when at the second position to be engaged with the
plunger (14) to prevent axial movement of both the needle support (24) and the
plunger (14) with respect to the body (11).

Revendications

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The Claims defining the invention are as follows:-
1. A syringe comprising a tubular body closed at one end and
open at the other end, a plunger receivable in the body to define a
chamber of variable volume, a needle support adapted to support and
accommodate a hollow needle, said needle support being supported
from, or in the wall of the body and being movable in a direction
substantially parallel to the main axis of the body between a first
position at which the needle extends from the one end of the body
and the interior of the needle is in communication with the chamber
and a second position at which the outer end of the needle is in a
retracted position, said needle support having a protrusion which is
selectively engagable with the wall of the body at the first and
second positions to be able to be retained at said positions and
receivable through the wall of the body at the second position to be
engaged with the plunger to prevent axial movement of both the
needle support and the plunger with respect to the body.
2. The syringe as claimed in claim 1, wherein the needle support
is rotatable about an axis substantially parallel to its direction of
movement and said protrusion extends radially from the needle
support, whereby rotation of the needle support will cause the
protrusion to pass through the wall of the body and engage the
plunger.
3. The syringe as claimed in claim 1 or 2 wherein the needle
support is receivable in a passage provided on or in the wall of the
body and is slidable along the passage to enable movement between
the first and second position.
4. The syringe as claimed in claim 3 wherein the passageway is
formed with a longitudinal slot which slidably receives the protrusion.

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5. The syringe as claimed in claim 4 wherein the slot is formed
with a transverse extension at a position corresponding to the
position of the protrusion at both the first and the second position
whereby rotation of the needle support will cause the protrusion to
engage with respective slot when at the first and second position.
6. The syringe as claimed in claim 5 wherein an aperture is
provided in the wall at a position adjacent the transverse slot at said
second position to permit the protrusion to pass through the wall to
engage the plunger.
7. The syringe as claimed in claim 6 wherein the aperture is
dimensioned to require resilient deformation of the protrusion and/or
the edges of the aperture to permit the passage of the protrusion
through the wall.
8. The syringe as claimed in any one of claims 1 to 7 wherein the
plunger is formed with a radial abutment surface along its length
which will engage the protrusion when in the engaged position to
prevent said axial movement of the plunger.
9. The syringe as claimed in claim 8 wherein the abutment surface
is located such that when the plunger is substantially fully received
within the body the abutment surface is capable of being engaged by
the protrusion.
10. The syringe as claimed in claim 8 or 9 wherein a plurality of
abutment surfaces provided along the length of the plunger.
11. The syringe as claimed in any one of claims 8 to 10 wherein
the abutment surface is provided by a recess in the side of the
plunger.

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12. The syringe as claimed in any one of claims 8 to 10 wherein
the abutment surface is provided by radial flange provided along the
length of the plunger.
13. The syringe as claimed in any one of claims 1 to 12 wherein
the protrusion comprises a enlargement which is receivable through
the wall of the body and is engagable with the plunger.

Description

WO 96110433 ~ ~ PCT/AU95/00650
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TITLE: SYRINGE
. THIS INVENTION relates to syringes and in particular syringes of the form
which
incorporate a retractable needle.
As a result of the need to develop practices which minimise the risk of
infection
the use of disposable syringes has become commonplace. The principal
difficulty of such syringes however relates in the need to prevent the spread
of
infection as a result of inadvertent "sticK' injuries. These can result from
accidents during the use of the syringes and the inappropriate disposal of the
syringe. In many cases these can be avoided if the pointed needle can be
stored
in a retracted position when not in use and in particular prior to disposal.
In
addition it is highly desirable to prevent such syringes from being reused. As
a
result syringes have been proposed in which the needle can be moved between
a retracted position and an extended position. Some of these syringes are
provided with a locking means which is able to prevent a used syringe from
being reused by lockingly retaining the needle of a used syringe in the
retracted
position to prevent its reuse. Examples of such syringes are disclosed in the
following patent specifications: AU-A-17419/92; US4927414; and US4941883.
A difficulty of such syringes however is that the plunger is still capable of
being
used to draw and force fluid from the chamber of the syringe which means that
if the needle can be disengaged from its locking engagement, the syringe can
be
reused.
It is an object of this invention to provide a syringe whereby when the needle
is
located in the retracted position in which it is fully accommodated within the
syringe body, it can be locked in that position.
Accordingly the invention resides in a syringe comprising a tubular body
closed
at one end and open at the other end, a plunger receivable in the body to
define
a chamber of variable volume, a needle support adapted to support and
accommodate a hollow needle, said needle support being supported from, or in
SUBSTITUTE SHEET tPULE 261

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the wall of the body and being movable in a direction substantially parallel
to the
main axis of the body between a first position at which the needle extends
from
the one end of the body and the interior of the needle is in communication
with
the chamber and a second position at which the outer end of the needle is in a
retracted position, said needle support having a protrusion which is
selectively
engagable with the wall of the body at the first and second positions to be
able
to be retained at said positions and receivable through the wall of the body
at the
second position to be engaged with the plunger to prevent axial movement of
both the needle support and the plunger with respect to the body.
According to a preferred feature of the invention the needle support is
rotatable
about an axis substantially parallel to its direction of movement and said
protrusion extends radially from the needle support, whereby rotation of the
needle support will cause the protrusion to pass through the wall of the body
and
engage the plunger.
According to a further preferred feature of the invention the needle support
is
receivable in a passage provided on or in the wall of the body and is slidable
along the passage to enable movement between the first an second position.
The passageway can be formed with a longitudinal slot which slidably receives
the protrusion. If desired the slot can be formed with a transverse extension
at a
position corresponding to the position of the protrusion at both the first and
the
second position whereby rotation of the needle support will cause the
protrusion
to engage with respective slot when at the first and second position.
According to a further preferred feature an aperture is provided in the wall
adjacent the transverse slot at said second position to permit the protrusion
to
pass through the wall to engage the plunger. The aperture is dimensioned to
require resilient deformation of the protrusion and/or the edges of the
aperture to
permit the passage of the protrusion through the aperture.

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According to a further preferred feature the plunger is formed with a radial
abutment surface along its length which will engage the protrusion when in the
engaged position to prevent said axial movement of the plunger. The abutment
surface can be located such that when the plunger is substantially fully
received
within the body the abutment surface is capable of being engaged by the
protrusion. If desired a plurality of abutment surtaces can be provided along
the
length of the plunger. In one form the abutment surface is provided by a
recess
in the side of the plunger. In another form the abutment surface is formed by
a
radial flange provided along the length of the plunger.
The invention will be more fully understood in the light of the following
description of several specific embodiments. The description is made with
reference to the accompanying drawings of which:
Figure 1 is a sectional side view of the first embodiment showing the
needle support in the extended position;
Figure 2 is a side elevation of the syringe body of the body of the first
embodiment without the needle support located therein;
Figure 3 is an end elevation of the first embodiment as shown at Figure 1;
Figure 4 is a sectional side view of the first embodiment with the needle
support in the retracted position;
Figure 5 is a cross section of the embodiment with the needle supported in
the retracted position and the protrusion in the locked position; and
Figure 6 is an isometric view of a plunger according to a second
embodiment of the invention.
The first embodiment as shown in the accompanying drawings comprises a
syringe of the general form disclosed in patent specification WO 88/08315. The
syringe has a tubular body 11 which is closed at one end 12 and is open at the
other end 13. The tubular body supports a plunger 14 which is slidably
received
within the body and is provided with a seal 15 at its inner end which defines
a

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VJO 96I1D433 PCT1AU95100650
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chamber 16 between the inner end of the plunger 14 and the one end 12 of the
body and which is of variable volume. The outer end of the plunger 14 is
provided with suitable handle 17 or manipulation means to facilitate gripping
of
the plunger by the operator and the other end 13 of the body is provided with
a
lateral flange 18 to facilitate.manipulation by the operator.
The side of the plunger 14 is formed with a recessed portion 19 which provides
a
pair of spaced abutment surfaces. The recessed portion is located towards the
other end of the plunger and is positioned to be located within the body 11
when
the plunger is fully received within the body 11.
The outer wall of the body is formed with a tubular portion 20 which provides
a
passage which is substantially parallel therewith. One end 21 of the tubular
portion 20 which is adjacent the one end 12 of the body 11 is formed as a
pointed tubular boss which may be formed to be capable of accommodating a
"LUER" or like fitting or alternatively may be pointed or similarly sharpened
to be
able to pierce a closure provided on a conventional phial or a like container.
The wall of the tubular member 20 between the other end 22 is formed with a
longitudinal slot 23.
The tubular member 20 slidably supports a needle support 24 which is slidably
received within the tubular member 20 to be movable towards a first position
at
which its one end 25 is adjacent the one end 21 of the tubular member 20 as
shown at Figure 1 and a second position as shown at Figure 4 at which the one
end 25 is remote from the one end 21 of the tubular member 20. The one end
of the needle support 24 is adapted to receive a hollow needle (not shown)
which when the needle support is in the extended position as shown at Figure 1
25 will extend through the tubular boss 21 to extend from the syringe body.
An opening 26 is provided between the chamber 16 and the interior of the
tubular member at one end of the body 11. The end 25 of the needle support 24
is adapted to sealingly engage the side walls of the interior of the tubular
member in the region of the opening 26 and provide communication between the

W O 96110433 °~ 2 Q ~ 7 PCT/AU95/00650
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opening 26 and the interior of the hollow needle when in the extended position
as shown at Figure 1.
The other end 27 of the needle support is provided with a radial protrusion 28
which is configured to be able to be manipulated to facilitate manual movement
of the needle support between the first position as shown at Figure 1 and the
second position as shown at Figure 4. The longitudinal slot 23 enables the
longitudinal movement of the protrusion 28 between those two positions. The
innermost end of the longitudinal slot 23 is formed with a transverse
extension
29 whereby when the needle support is in the first position as shown at Figure
1,
the needle support can be caused to rotate about its central axis whereby the
protrusion 28 is received in the innermost transverse slot 29 and the needle
body is retained in the extended first position. A second transverse slot 30
is
provided towards the outer end of the longitudinal slot 23 whereby on rotation
of
the needle support 24 when the protrusion 28 is in the region of the second
7 5 transverse slot, the protrusion 28 can be moved laterally.
In order to lockingly retain the needle support in the second position and
limit the
movement of the plunger the wall of the body 11 on the corresponding side of
the tubular member 21, and at the location of the second transverse slot 30 is
formed with an aperture 31 which is configured to receive the protrusion 28 on
rotation of the needle support 24 within the tubular member 20. The location
of
the transverse slot 30 and aperture 31 corresponds to the position of the
recessed portion 19 of the plunger 14 when the plunger is fully accommodated
within the tubular body 11.
As shown at Figure 5, the protrusion is configured such that when the plunger
is
fully received within the body and the needle support is in its retracted
second
position the needle support can be caused to rotate about its central axis
whereby the protrusion 28 is able to move through the transverse slot 30 and
through the aperture 31, to be received within the recessed portion 19 of the
plunger 17. The aperture 31 is slightly smaller than the protrusion 28 such
that
when the protrusion 28 is caused to rotate into engagement with the aperture

WO 96/10433 pCT/AU95/00650
i
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31, and is fully engaged therewith such that its outer edge moves past the
inner
face of the wall of the body of the tubular body, the wall in the region of
the
aperture and /or the protrusion is caused to undergo some resilient
deformation
to permit the movement of the protrusion through the wall. As result the
protrusion becomes positively engaged within the body and cannot be easily
extracted from the body without damaging the body, or the protrusion or the
needle support. Once so engaged, the needle is fully accommodated within the
tubular member 20, the plunger 14 is fully accommodated within the body 11
and the syringe is unusable since the needle support and plunger have been
lockingly and substantially irretrievably engaged with the body 11.
According to an alternative form of the first embodiment the plunger may be
formed with a number of recessed portions along the length whereby the syringe
can be rendered unusable, even if not empty.
According to a second embodiment as shown in Figure 6 the plunger may be
formed with a plurality of radial flanges 35 to provide abutment surfaces. The
flanges 35 serve the function of the recessed portion 19 of the first
embodiment
Once the protrusion 28 is received through the aperture 31 the presence of the
flanges will limit the relative movement of the plunger within the body. The
number of flanges can be varied as desired.
It should be appreciated that the scope of the present invention need not be
limited to the particular scope of the embodiment described above.

Dessin représentatif