U.S. patent application number 14/681539 was filed with the patent office on 2015-07-30 for injection devices.
The applicant listed for this patent is OWEN MUMFORD LIMITED. Invention is credited to Stephen BICKNELL, Mark EATON.
Application Number | 20150209525 14/681539 |
Document ID | / |
Family ID | 38543377 |
Filed Date | 2015-07-30 |
United States Patent
Application |
20150209525 |
Kind Code |
A1 |
BICKNELL; Stephen ; et
al. |
July 30, 2015 |
INJECTION DEVICES
Abstract
An injection device includes a forward housing, a drive housing
that has a forward end configured to be attached to and detached
from a rear end of the forward housing, a syringe holder mounted
within the forward housing for longitudinal movement with respect
to the forward housing, and a syringe with a needle that is mounted
in the syringe holder. The drive housing includes a drive
mechanism, and the syringe holder includes detent means for
engaging the syringe to prevent or limit relative axial movement of
the syringe relative to the syringe holder.
Inventors: |
BICKNELL; Stephen;
(Warwickshire, GB) ; EATON; Mark; (Oxon,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
OWEN MUMFORD LIMITED |
Oxford |
|
GB |
|
|
Family ID: |
38543377 |
Appl. No.: |
14/681539 |
Filed: |
April 8, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12672914 |
Apr 27, 2010 |
9022989 |
|
|
PCT/GB2008/002741 |
Aug 11, 2008 |
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14681539 |
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Current U.S.
Class: |
604/110 ;
604/198 |
Current CPC
Class: |
A61M 5/326 20130101;
A61M 5/2033 20130101; A61M 2005/202 20130101; A61M 2005/2073
20130101; A61M 5/3245 20130101; A61M 2005/3246 20130101; A61M
5/3204 20130101; A61M 2005/3142 20130101; A61M 2005/3247 20130101;
A61M 2005/206 20130101 |
International
Class: |
A61M 5/32 20060101
A61M005/32 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 10, 2007 |
GB |
0715623.5 |
Claims
1. An injection device comprising, a forward housing; a drive
housing having a forward end configured to be attached to and
detached from a rear end of the forward housing, the drive housing
including a drive mechanism; a syringe holder mounted within said
forward housing for longitudinal movement with respect to said
forward housing; and a syringe having a needle, wherein said
syringe is mounted in said syringe holder, said syringe holder
including detent means for engaging said syringe to prevent or
limit relative axial movement of the syringe relative to the
syringe holder.
2. An injection device according to claim 1, wherein said detent
means are provided at a rear end of the syringe holder.
3. An injection device according to claim 1, wherein said syringe
includes a rear end having a radially extending skirt.
4. An injection device according to claim 3, wherein said detent
means include snap detent features which engage a rear surface of
the syringe skirt when the syringe is mounted within said syringe
holder.
5. An injection device according to claim 1, wherein said syringe
holder is slideably mounted in said forward housing.
6. An injection device according to claim 5, wherein said syringe
holder is provided with at least one engagement feature on its
outer surface which engages said forward housing to limit rearward
movement of the syringe holder.
7. An injection device according to claim 5, wherein said the
syringe holder is provided with a snap fit annulus having a
rearward facing shoulder, wherein the rearward facing shoulder
engages with said a forward facing surface provided on an inner
surface of said forward housing to limit rearward movement of the
syringe holder.
8. An injection device according to claim 1, wherein said syringe
being mounted in said forward housing portion for movement between
a rearward position in which said needle is shrouded by a forward
part of said housing portion, and a forward position in which said
needle projects forwardly of said housing for delivery of a dose;
and wherein the device is further provided with a locking
arrangement for locking said syringe in a rearward position, and
being releasable to allow forward movement of the syringe; and a
latch arrangement operable to latch the released syringe as it
returns to a rearward position after delivery of a dose.
9. An injection device according to claim 8, wherein said syringe
is held in a syringe holder and said locking arrangement and said
latching arrangement cooperate with said syringe holder to lock and
latch said syringe respectively.
10. An injection device according to claim 9, wherein said locking
arrangement and said latching arrangement are defined by a common
moveable locking/latching element moveable between: a
locking/latching position in which it i) prevents movement of said
syringe forwardly from a rearward position, and ii) latches said
syringe when returning from a forward position towards a rearward
position; and an unlocked position in which the syringe is allowed
to move forward.
11. An injection device according to claim 10, wherein said
latching/locking element comprises at least one latch portion
moveable generally transversely relative to the syringe between
said locking/latching position and said unlocked position
Description
[0001] This invention relates to injection devices and in
particular, but not exclusively, to automatic injector devices
having a mechanism which moves a syringe within the device
forwardly so that the needle tip projects from the device and then
delivers the dose through the needle.
[0002] Many automatic injectors are designed to deliver one dose
and then to be discarded after use. Although often the cost of the
drug dispensed is much greater than the cost of the injector
device, there is a concern to reduce the cost of the drug delivery
system and also an environmental desire to reuse components where
necessary. We have therefore designed an automatic injector device
in which the drive mechanism may be reused and provided as a
separate module which is screwed or otherwise coupled to a housing
containing the syringe, so that the driver module can be reused
many times. However the design of such a device means that internal
access to the forward portion is possible and so it is desirable to
provide some means of preventing movement of the syringe in the
housing when separate from the drive module, so as to prevent the
possibility of a syringe being pushed forwardly in the housing to
expose the needle either before or after use. In other, manually
operated devices, it is also desirable to disable or make safe an
injection device before and after use.
[0003] Accordingly, in one aspect, this invention provides an
injection device comprising: [0004] a main housing portion; [0005]
a syringe having a needle, said syringe being mounted in said
housing portion for movement between a rearward position in which
said needle is shrouded by a forward part of said housing portion,
and a forward position in which said needle projects forwardly of
said housing for delivery of a dose; [0006] locking means for
locking said syringe in a rearward position, said locking means
being releasable to allow forward movement of the syringe, and
[0007] latch means operable to latch the released syringe in a
rearward position after delivery of a dose.
[0008] The syringe is conveniently held in a syringe holder that
cooperates with said locking means and said latching means.
[0009] Preferably said locking means and said latching means are
defined by a common moveable locking/latching element moveable
between: [0010] a locking/latching position in which it (i)
prevents movement of said syringe forwardly from a rearward
position, and (ii) latches said syringe against forward movement
when returning from a forward position towards a rearward position,
[0011] and [0012] an unlocked position in which the syringe is
allowed to move forward.
[0013] The latching/locking element may comprise at least one latch
portion moveable generally transversely relative to the syringe
between said locking/latching position and said unlocked position.
Each latch portion may be carried on a respective finger moveable
transversely between said locking/latching position and said
unlocked position. Thus a plurality of latching portions may be
provided on arcuate wall portions of a generally cylindrical
resiliently expandable locking sleeve.
[0014] Said locking sleeve is preferably releasable by axial
engagement and shifting of said wall portions by a release ring
portion.
[0015] Where the device includes a driver mechanism disposed in a
drive housing having a forward end for releasable engagement with
the rear end of said housing portion, said locking means and said
latching means may be designed to be released upon a predetermined
extent of engagement between said drive housing and said main
housing portion.
[0016] Where said main housing portion and said drive housing
portion are threadedly engageable said drive portion may carry a
release ring portion for engaging said locking sleeve.
[0017] Whilst the invention has been described above, it extends to
any inventive combination of the features set out above, or in the
following description.
[0018] The invention may be performed in various ways, and an
embodiment thereof will be described by way of example only,
reference being made to the accompanying drawings in which:
[0019] FIG. 1 is a side view of an automatic injector with a
separate drive module screwed onto the rear end of a forward
housing containing the syringe;
[0020] FIG. 2 is a longitudinal sectional view taken on lines:II-II
of FIG. 1;
[0021] FIG. 3 is a detailed view on the latching sleeve;
[0022] FIG. 4 is an isometric view looking rearwardly on the drive
module;
[0023] FIGS. 5(a) and (b) are enlarged views showing the latch
sleeve in its latching position and its open position
respectively.
[0024] FIG. 6 is a view similar to FIG. 1 but showing the device
when fired, and
[0025] FIG. 7 is a section view showing the forward portion
unscrewed from the drive module after use.
[0026] Referring to the drawings, the embodiment of injection
device disclosed therein is an automatic injector comprising a
drive module 10 which can be screwed into the back of a syringe
housing 12 to prepare the injector ready for use. The device has a
firing button 14 at its rear end and the front end of the syringe
housing is initially covered by a cap 16. The drive module 10
slideably supports a drive plunger 18 which is urged forwardly by
means of a drive spring 20. At the rear end, the plunger 18 is
formed with a split arrowhead configuration 22 which enables the
plunger to latch in a cocked position behind an internal wall in
the module casing.
[0027] In order to fire the device, the firing button 14 is rotated
from a safe to an armed position and then pushed forwardly so as to
squeeze the arrowheads together releasing the plunger for forward
movement under the influence of the drive spring 20. Forward
movement of the plunger is limited by an annular rib 26 which
co-operates with an end wall in the drive housing 10. The forward
end of the drive plunger 18 is of reduced diameter to fit within a
bung 28 of the syringe 30. At its front end, drive module 10 has a
female threaded portion 32 threadable onto a corresponding male
threaded portion 34 on the rear of the syringe housing 12.
[0028] The syringe housing 12 slideably receives a syringe holder
36 mounted for slideable movement within the housing 12, urged
rearwardly by a compression spring 38, the rearward movement being
constrained by a shoulder on a snap fit annulus 40 on the syringe
holder. The syringe 30 is concentrically held within the syringe
holder 36 by snap detent features 37, that clip behind the skirt at
the rear end of the syringe, and moves axially therewith between
the rearward position shown in FIG. 2 and the forward position
shown in FIG. 6.
[0029] Concentrically surrounding the syringe holder 36 and the
spring 38 is a cylindrical latching she 42 whose form can be seen
more clearly in FIG. 3. The latching shell 42 has slots dividing
its cylindrical surface into six arcuate resiliently deformable
arms 44, each having an internally directed barb 46 short of the
end thereof. The free ends of the resilient arms 44 are chamfered
as shown at 48.
[0030] The latching sleeve 42 is acted on by a release ring portion
50 on the front end of the drive module so that, as the drive
module is screwed into the back of the syringe housing, the release
ring portion 50 engages the chamfered portions 48 to splay out the
resilient arms 44 to lift them from the locking position, shown in
FIG. 5 where they abut and block the path of movement of a shoulder
52 on the syringe holder 36, to the splayed position shown in FIG.
5, where the arms are deflected outwardly so that the barbs 46 are
clear of the path of movement of the syringe holder 36.
[0031] The co-operation of the release ring portion 50 and the
latching sleeve 42 means that, when the syringe housing 12 is
separated from a drive module 10, the sleeve is in its relaxed
position in which the barbs 46 block movement of the syringe
carrier 36. Also, after use, when the drive module 10 has been
unscrewed from the syringe housing the barbs again return to their
locking position to latch and prevent forward movement of the used
syringe as it returns to its rear position.
[0032] The cap 16 may have inwardly directed fingers or a suitable
engagement surface (not shown) which grips a sheath (not shown)
initially covering the syringe needle, or otherwise engages the
sheath so that removal of the cap from the device also pulls the
sheath off the needle.
[0033] In use, the drive module is cocked and the cap is removed
from the front end of a syringe housing. The drive module is then
screwed into the back of the syringe housing. Towards the end of
the threaded engagement the release ring portion 50 engages the
chamfers 48 thus splaying the arms of the latching sleeve to
release the syringe holder 36 for movement.
[0034] The device is then offered up to the user's skin. The button
14 is turned to the armed position and pressed to release the
plunger. The plunger shoots forward driving the syringe 30
forwardly with it due to the incompressible nature of the syringe
contents so that the needle projects beyond the forward end of the
housing. The syringe is arrested and the spring 38 is fully
compressed and thereafter the plunger drives the bung 28 forwardly
to expel the dose. At this stage the components are in the
configuration shown in FIG. 6.
[0035] The user then unscrews the drive module 10 from the syringe
housing 12 and the release ring 50 is drawn out of engagement with
the latching sleeve so that it returns to the position shown in
FIG. 5. The syringe carrier is urged rearwardly by the spring 38 as
the drive module is unscrewed and, when the parts separate and the
drive module 10 is pulled away from the forward housing, the
syringe carrier snaps past the barbs 46 so that it is locked in its
rearward position.
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