Note: Descriptions are shown in the official language in which they were submitted.
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I_IOUID DELIVERY CONTAINER
Technical field
The present invention relates to Pressurisable containers for storing and
ejecting liq-
S uid, the container comprising a) a front wall having or surrounding a cavity
corresponding to
the form of an open vessel, b) an opening in the front wall adapted for
ejection of the liquid
from the container, said opening defining a container axis, c) optionally a
sealing over the
opening adapted for temporary use, and d) a rear wall closing and sealing the
open part of the
front wall vessel to confine a space for the liquid in the container, the rear
wall running at
least partially perpendicular to the container axis and being displaceable or
deformable for
movement towards the opening to pressurize the container liquid. The invention
also relates to
methods for container manufacture and devices and methods for ejecting liquid
from the con-
tainers.
Backeround
I S Liquid containers designed not only to hold and store the liquid but also
to deliver or
expel the liquid tend to be growingly complex when the control demands on the
delivery pat-
tern increases. Whereas the complexity and expense, e.g. in pump systems, can
be accepted
under certain circumstances, such as in re-usable or mufti-dosing devices,
these conditions are
not always present. It is for example often desirable to provide a single
sealed container for
each liquid dose to be delivered, e.g. to exactly control the dose and
maintain sterility until the
use moment in medical delivery applications, and under these unit dose
circumstances the
price restrictions becomes decisive. The design constraints may become still
more severe
with added requirements on delivery quality, e.g. in respect of delivery
pressure, liquid speed,
precise targeting, jet coherence, rapid stream rise and fall, fast delivery,
small losses, precise
dosing etc. High chamber pressures, e.g. to give high jet speeds or atomizing
degrees, may
counteract the cost aspect by requiring thick walls of special 'design or
elaborate supports for
the chamber or counteract the targeting by rupture, instability or dislocation
of the opening.
.let coherence may require a precise opening channel inconsistent with minimum
material and
manufacturing conditions. High dosing precision requires complete chamber
emptying and
small losses, in turn requiring rapid pressure build up and fall, placing high
demands on cavity
stability and controlled collapse of the pressurizing wall. Secondary factors
also need consid-
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2
eration. It is for example common to provide a temporary seal over the opening
in order to
fully seal the container before use and arrangements need to be present for
rupture or removal
of the seal in connection with delivery. Also, apart from the container
properties as such, cer-
taro rigidity and additional structures may be needed for retaining the
container in a delivery
device fixture or seat. In order to avoid handling of individual unit dose
containers it is also
desirable to provide units of multiple connected containers for sequential
firing in a dispenser
device, which may require additional structural rigidity and features for
feeding and stabiliz-
ing the individual containers in a device firing position. Manufacturing
demands include both
efficient production of the container parts as well as rational filling and
sealing of the contain-
ers under high purity and even sterile conditions.
Prior art suggestions have met the abovesaid requirements only to a limited
extent.
The US patent specification 4090642 describes a tape having multiple pockets
for a flowable
material and represents liquid dispensing with low delivery and control
requirements since the
flowable material is only to be squeezed out on the tape surface for contact
application to the
skin. The US 5497763 specification relates to a system including a similar
multiple dose tape
for atomizing liquid to be inhaled. The delivery requirements are still low as
atomization takes
place with a separate vibrator and the demands on the tape reduce to liquid
outflow through a
porous membrane. The GB 2255918 specification similarly relates to droplet
formation for
inhalation purposes but liquid atomization here takes place by forcing the
liquid through nar-
row container openings. In spite of the higher demands the proposed containers
are separate
collapsible containers or blister type sheets with multiple containers,
requiring heavy support
in the dispensing device when the pressure is applied to a dome shaped rear
wall, the collapse
of which cannot be fully controlled. It should also be noted that for the
purposes described no
liquid targeting is needed and no liquid stream formation since in connection
with inhalation a
mist of droplets is passively drawn into the lungs by the patient, even
allowing redirection of
the stream. The same applies for powder inhalers, as exemplified by WO
90/13328, GB
2242134, DE 19500726, WO 97/04827, US 4811731, US 5207217, US 5415162, EP
469814,
EP 129985 and US 4627432, additionally different in that no atomization at all
takes place
and no discharge from nozzle type openings. Accordingly such demands are not
considered
and no container design suitable for such purposes is proposed. The WO
96/00050 and EP
224352 specifications do relate to the generation of a stream of droplets,
actively shot and
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targeted towards an eye and able to traverse an air gap by own inertia.
Typically, however, the
dispenser arrangements required are elaborate and no suggestions are given for
individual unit
dose containers with integral delivery nozzles. The WO 96/06581 and 97/23177
specifications
suggest such unit dose containers for similar eye treatment purposes. While
meritorious in
many respects the container designs proposed are similar to those already
known and dis-
cussed, i.e. either elaborate separate containers or flexible bands with
multiple blister type
pockets having bulb type walls to be collapsed.
Accordingly there remains a need for improved integrated unit dose sealed
container
systems suitable both for liquid storage and liquid delivery under high
control and quality
demands.
Summar~of invention
A main object of the present invention is to avoid the abovesaid disadvantages
of hith-
erto used container systems. A more specific object is to offer a unit dose
sealed container
system suitable both for liquid storage and liquid delivery under high control
and quality de-
mands. A further object is to provide such a system meeting high demands in
respect of liquid
speed, precise targeting, jet coherence, rapid stream rise and fall, fast
delivery, small losses,
precise dosing and/or complete container emptying. Another object is to offer
a system al-
lowing high chamber pressures with maintained container integrity and without
rupture, insta-
bility or dislocation of the opening. Still another object is to offer a
system allowing con-
trolled collapse of the pressurizing wall. Yet another object is to offer a
system useful for
varying degrees of liquid stream momentum, e.g. characterized as low, moderate
and high,
allowing all from smooth application to penetrating strength. Another object
is to offer system
containers of low cost in material, component manufacture and filling. Still
another object is
to offer containers of high rigidity and stability. Yet another object is to
provide such con-
tamer designs suitable for multiple container units useful for sequential
delivery of doses. An-
other object is to provide containers facilitating dispenser device design and
requiring limited
support at delivery. Another object is to provide a system easy to handle and
convenient to
operate for the end user.
These objects are reached with the characteristics set forth in the appended
patent
claims.
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4
By use of a container sealing, collapsible, backing rear wall which before
collapse
have an overall planar or single-curved shape several precision related
objects are reached.
For each front wall overall shape the rear wall will have a minimum surface,
giving volume
and shape stability before collapse and a foreseeable and controlled collapse
during pressuri-
zation of the container as no buckling, folding or crumpling of the wall is
needed as in corre-
sponding flattening or inversion wall deformations. A stretchable material in
the wall will
allow the wall to increase its surface during collapse, hereby avoiding
rupture, permitting dy-
namic adaptation to any ram or hammer tool surface used for forced
displacement of the wall
and allowing the wall to conform to the opposite container cavity surface, all
serving to give
controlled pressure response, including initiation, continuation and fall, and
precision in dos-
ing and container emptying. Manufacturing advantages are reached among others
in that the
wall form facilitates its production, its sealing to the front wall in filling
procedures and its
joint attachment to several containers in multiple compartment units or
packages. Handling,
convenience and dispenser device design advantages are reached in that the
initial wall shape
may be used to give smooth rear wall surfaces and does not build on the
boundaries of the
material used for the vessel front wall design. Said front wall is relied upon
for overall con-
tamer static and dynamic rigidity. Contrary to blister type containers, the
present vessel wall
can be designed freely and needs not depend on the curvature of pressed
structures for rigid-
ity, can have a wall thickness at each location adapted to its functional
object and needs not be
locally weakened by stretch operations and can have an integral opening
determined by design
and not by manufacturing necessities. Wall stability is essential to volume
control and the
possibilities for consistent emptying. Wall and opening strength is essential
to pressure resis-
tance and the operative range of the system, reliable targeting and stable and
coherent liquid
jets. It also reduces the needs for extensive container support arrangements
in the dispenser
device and facilitates sequential feeding of containers into a shoot position.
If the rigidity ad-
vantages are used to avoid bulb wall parts, dispenser container seat and
feeding mechanism
can be further simplified. Still the option is retained of providing multiple
container units and
is now not limited to tapes and other flexible structures but can with
advantage be formed into
self bearing structures with improved handling and convenience
characteristics, similar to that
of individual containers. The vessel wall can for example be implemented as
the resulting
structure when forming the container cavity in an otherwise flat or single-
curved plate, al-
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lowing both single and multiple container units of high structural rigidity
and simple outer
form, to the benefit of manufacture, dispenser design and end user handling,
allowing free
cavity designs e.g. for suitable flow characteristics and device head design
as well as allowing
opening designs of any length and form with high dynamic stability. Similar
advantages are
obtained if implemented with substantially constant vessel wall thickness or
with increasing
wall thickness when moving lateral out from the opening location of the wall.
The vessel
walls with opening in place can be manufactured as an integral, single
material, structure e.g.
by heat molding in common plastic tools, without need for stretch operations
or separate noz-
zle forming steps, and are easily filled with liquid and sealed by the rear
wall.
Further objects and advantages of the invention will be evident from the
detailed de-
scription hereinbelow.
Definitions
As used herein the expression °'single-curved" shall be understood as
any form of a
plane or surface obtainable from the same plane in flat form, without
stretching or shrinking
any part thereof in any direction within the plane, i.e. with maintained total
surface for both
the whole plane and any part thereof. In contrast, a "double-curved" plane or
surface can only
be obtained from a flat plane if deformed by stretching or shrinking. A
curvature shall be re-
garded "continuous" if the change in curvature is constant or has a smooth
variation and shall
be regarded as "discontinuous" if there is a sharp change in the plane
direction. As physical
and non-limiting examples a cylinder surface or a corrugated surface are
single curved as they
can be formed from a non-elastic sheet, e.g. paper sheet, by pure bending
whereas the surface
of a sphere or saddle cannot be so formed without stretching and accordingly
are double-
curved. All these surfaces are continuous by having smooth curvature changes
whereas for
example a sheet with sharp folds are discontinuous at the fold lines.
As used herein "system" shall be understood to refer to the invention
generally, when
including its parts, such as the container and dispenser devices therefore, as
well as methods
for part operation and use.
In the absence of explicit statements to the contrary, as used herein
expressions like
"comprising", "including", "having", "with" and similar terminology shall not
be understood
to be exclusively restricted to recited element but shall be understood to
allow for the presence
of further elements as well and shall be understood to cover any element in
integral, subdi-
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6
vided or aggregate forms. Similarly, expressions like "connected", "attached",
"arranged",
"applied", "between" and similar terminology shall not be understood to cover
exclusively
direct contact between the recited elements but shall be understood to allow
for the presence
of one or several intervening elements or structures. The same applies for
similar expressions
when used for description of forces and actions.
Also as used herein, positional and directional statements for both the
container and
the delivery device, such as "axial", "front" and "rear" and "forward" and
"rearward", shall be
understood with reference to the liquid delivery direction, with respect to
which a line cen-
tered in the container opening and drawn along the main or average delivery
direction shall be
regarded as the system "axis" along which axis the liquid is delivered in the
forward direction.
Detailed description
The container can be said roughly to include a front wall and a rear wall
between
which the container space, or enclosure, for the liquid is confined.
The container space is formed mainly between the front wall and the rear wall
and in-
cludes a cavity part formed in, or surrounded by, the front wall. Although the
space available
for the liquid may be larger than the volume of the cavity proper, e.g.
additional small volume
in the opening and in a rearward protrusion or curvature of the rear wall, it
is preferred that the
cavity constitutes the major part of the space, especially when the rear wall
in the preferred
manner is substantially flat or single-curved. The cavity surface preferably
has the shape of
the space of a vessel, opening towards the rear wall and having its closed
bottom toward the
front wall. Among others in order to facilitate complete emptying and form
adaptation be-
tween cavity and driving ram, it is preferred that the cavity has little, and
preferably no, un-
dercut parts when seen from the rear side. This may be accomplished with
vessel surface parts
being parallel with the cavity axis, e.g. cylindrical parts, but preferably
the surface widens all
the way from the axis and laterally outwards, to create a generally concave
deepening when
seen from the rear wall side. Although the surface may have sharp
discontinuities, e.g. be-
tween an axial cylindrical surface and a more flat front part, it is preferred
e.g. for rigidity
reasons that the surface is substantially smooth and continuous. The cavity
shape in cross-
section planes perpendicular to the axis can have any shape, e.g. oval or
polygonal, although
preferably circular. Suitable overall forms are that of a dome or segment of a
sphere. As
known per se the space may be divided into two or more separate chambers, e.g.
for sequen-
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7
tial delivery or for mixing in connection with delivery, for example by use of
interior walls
running perpendicular or parallel with the axis. Such walls can be manually
removable before
actual delivery or may be rupturable in connection with delivery.
Alternatively adjacent con-
tainers may contain different liquids and eject substantially simultaneously,
either as two dis-
Crete jets or jets mixing in connection with ejection, e.g. by openings
arranged offset and close
to each other or directed towards each other.
The front wall is preferably more rigid than the rear wall, by comprising more
rigid
materials and/or material of thicker dimensions. For reasons outlined it is
beneficial that the
front wall provides the container and its opening with rigidity and stability
and preferably the
front wall alone is able to provide such rigidity, leaving the rear wall
design free for other
considerations. As long as these demands are met the front wall can have a
variety of configu-
rations. The front wall may have a roughly constant thickness when measured
normal to the
cavity surface, making the front wall shape about congruent with the cavity
surface. It is pre-
ferred, however, that the wall thickness measured as stated has a variation
and preferably so
that the thickness increases when moving away from the axis. This gives the
container as a
whole a high targeting and pressure sustaining stability while allowing a
short and low friction
opening design. This in sharp contrast to blister type containers where
stretch manufacture of
the bulb results in weak lateral wall parts with low overall container
stability. A preferred way
of arranging for abovesaid variation in wall thickness is to make the front
surface of the front
wall substantially flat or single-curved, flat being most preferred, giving a
lot of manufactur-
ing and handling advantages as indicated. It is further preferred that also
the rear surface of
the front wall in the neighborhood of the cavity, and disregarding the form of
the cavity
proper, is single-curved and most preferably flat, giving similar
manufacturing and handling
advantages. Among others the flat or single-curved surfaces allow attachment
thereto of origi-
nally flat sheets, films or foils without stretching thereof, e.g. a sealing
film on the front sur-
face and the backing rear wall on the rear surface of the front wall. Most
preferably the front
and rear surfaces are parallel or concentric respectively, giving e.g. overall
plate or cylinder
type structures, having good rigidity, handling and manufacturing properties.
The opening design can vary depending on the nature of the liquid stream to be
pro-
duced, e.g. an atomized spray or a concentrated stream to remain coherent or
to break up into
a linear stream of discrete droplets. Also the stream speed may vary from high
penetrating to
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low impact surface delivery. Several or multiple openings can be provided,
e.g. to produce a
controlled shower, although for most applications a single opening is
preferred. The opening
geometry can be that of a simple tube, diverging, e.g. for assisting in a
distributed spray, con-
verging, e.g. for assisting in a coherent stream to be formed, or a
combination, such as a ven-
turf type of channel. It is generally preferred to make the duct part of the
opening short in or-
der to keep the flow friction low. The desirable front wall thickness at the
opening area can
still be controlled, e.g. for rigidity purposes, e.g. by cutouts around the
opening, preferably on
the front surface of the front wall, also assisting in attaching a sealing
film over the opening in
a manner not interfering with the opening proper. The positioning of the
opening with respect
to the cavity can be asymmetrical, for example laterally offset towards the
cavity side e.g. for
mixing of adjacent jets, although normally it is preferred that the opening is
symmetrically
arranged with respect to the cavity, e.g. concentric with any cavity symmetry.
Although the above considerations apply to individual containers for single
and dis
crete use it is preferred to provide for multiple container units or packages.
This can be done
by joining several individual container into multiple structures, e.g. by
flexible joints to allow
structures that can be bent, folded or rolled. Preferably, however, the
multiple container pack-
age is a substantially rigid and self bearing structure, among others giving
advantages in con-
nection with the delivery device. A rigid structure can be obtained by joining
the individual
containers by rigid joints but a preferred way is to utilize the rigidity of
the front wall as de-
scribed by providing an enlarged front wall structure and provide several
cavities in the
structure, among others facilitating manufacture of multiple containers and
allowing a smooth
and non-complicated exterior. By utilizing the feature of making the front
and/or rear surface
of the front wall structure flat or single-curved the attachment of films over
these surfaces is
further simplified, especially if the container surfaces lies in the same
plane since an undi-
vided sheet material can then be attached to several, and preferably all, of
the individual con-
tainers of the structure, e.g. a common foil attached as rear wall to the rear
surface of structure
or a common peel sheet over the container openings at the front surface.
The overall shape of the front wall structure for multiple containers can take
a variety
of forms. A single-curved form for example can take the form of a partial or
complete cylin
der, allowing many containers on a limited volume and giving a very rigid
structure. The
container openings can be arranged on the cylinder exterior, e.g. if the
dispenser device ram is
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9
arranged to hit from inner or concave side of the full or partial cylinder or
if openings are pro-
vided diametrically opposite each rear wall for ram access therethrough from
outside the cyl-
inder. The container openings can be arranged on the cylinder interior, e.g.
for simple exterior
ram access to the rear wall and also in this case a diametrically opposite
hole can be provided
for passage of the liquid jet. Essentially flat front wall structures give
advantages in manufac-
ture and delivery device design. The shape may for example be rectangular,
square or round.
The round "disc" shape has been found particularly beneficial, among others in
connection
with the delivery device where sequential feeding of the containers into a
shoot position can
be made by simple rotation in a "revolver" type manner, the absence of any
particular start
position facilitates handling and counting arrangements and allows for self
centering proper-
ties.
The layout of the multiple containers on the available structure surface can
be made in
various ways. The containers can be arranged in a row or line, e.g. to avoid
two dimension
feeding. Alternatively several rows can be provided along several lines in two
dimensions,
1 S e.g. parallel or concentric, to allow for a compact container arrangement.
The above design considerations for the front wall mainly apply to the parts
occupied
by containers, but other structures may be included for secondary purposes,
e.g. for gripping,
holding, centering or feeding discrete or multiple containers, in manufacture,
in the delivery
device and by the user, for adhering or removing sealing film etc. and these
parts can be de-
signed freely for their respective purposes.
The front wall is preferably made from suitable inert plastic materials such
as polyeth-
ylene or polypropylene, possibly with reinforcing fillings of e.g. glass
fibres, and can be
manufactured in various ways, e.g. the cavities with opening can be made by
machining in a
raw material blank but the structures described can easily be formed in one
step, e.g. by
pressing although preferably by injection molding since all structures,
including the opening,
can be obtained with a dividable molding tool. Although the front wall can be
made of a lami-
nate or other composite material a single material is generally sufficient.
As said the rear wall serves the purposes of sealing the rear part of the
container before
ejection of the liquid and allowing collapse of the cavity during ejection.
The rear wall should
run at least partially perpendicularly relative the opening axis, i.e. forming
a non-zero angle
therebetween and preferably runs substantially perpendicularly thereto. The
requirements on
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the rear wall material for sealing purposes depend on the particular
application and liquid in-
volved but generally it is desirable that the wall material is highly
impermeable. It is also de
sirable to avoid solvents and other volatile components, both in the wall
material and when
attaching the rear wall to the font wall and preferably these parts are joined
by heat sealing
5 rather than by glue or adhesives. For the collapse purposes it is possible
to have a rear wall
material that breaks or ruptures when hit with the ram of the dispenser
device, which, how-
ever, requires good sealing between ram and cavity. Hence it is preferred that
the rear wall can
be deformed without rupture, and most preferably be deformed to such an extent
that it can fill
out and conform to the inner surface of the cavity. The requirements for
deformability can be
10 reduced if the rear wall film is folded, e.g. in a continuous corrugated
manner or in a discon-
tinuous folded manner, i.e. in both cases with maintained single-curved shape,
e.g. along sin-
gle or multiple parallel lines over each container, to allow for unfolding as
part of the defor-
mation. In order to obtain a most controlled and reproducible collapse,
however, it is preferred
that no additional folds are used but that the rear wall when attached has
substantially the
same shape as the rear surface of the front wall. In any case the deformation
during ejection
will result in that the rear wall flat or single-curved shape is at least to
some extent changed
into a double-curved form, requiring some stretching of the material. The
stretching and de-
formation can be elastic, as in a rubber sheet, e.g. if repeated use is
intended, but is preferably
at least partially and preferably substantially plastic in an irreversible
manner, e.g. in order to
avoid reuse of disposable containers or to prevent aspiration of air or liquid
remains into the
container after use. The rear wall preferably has the form of a sheet, film or
foil of even thick-
ness, which preferably is small compared to the front wall. The sheet may
consist of a single
material but preferably a composite material is used to meet all the
requirements indicated.
Most preferably the sheet is a laminate. Preferably the laminate comprises at
least one imper-
meable and diffusion retarding layer, preferably a metal layer such as an
aluminum layer, and
at least one stretchable layer allowing deformation, preferably a plastic
layer, e.g. of polyeth-
ylene, optionally also a heat sealable layer if the plastic layer does not
have this property. In
such a laminate it is acceptable that the metal layer breaks during wall
collapse as long as re-
maining layers provide sufficient resilience for the deformation described.
As indicated it is preferred to temporary seal the container opening or
openings before
actual ejection of the liquid in order to maintain a fully sealed container.
The seal should be
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11
broken or removed immediately before use. Although a manually or pressure
breakable rup-
turable seal can be used it is often preferred to use a removable seal in
order to avoid any par-
ticle release from the seal, to have a fully foreseeable dynamic behavior and
allow use of more
reliable thick or strong layers. Generally a seal can be formed integral with
the front wall, e.g.
S by molding so as to leave a membrane of material somewhere in the opening
duct. Preferably,
however, a separate peel layer is provided for removal prior to ejection, and
preferably at-
tached to the front surface of the front wall. Again it is preferred to avoid
glue and adhesives
and preferably some form of welding is used, as by ultrasonic or heat. In
order to facilitate
removal and interference with the opening area the sealing can be made to a
limited area sur-
rounding the opening. In multiple container structures it is preferred to make
the layers indi-
vidually removable for each container, e.g. by use of separate films, pre-cut
films or separate
tongues, e.g. in a star shape for a round disc. For the film material similar
considerations ap-
ply as for the rear wall material, although the film need not be deformable by
stretching and
the demands on impermeability can be slightly reduced in view of the small
opening area.
The parts described should be joined and liquid filled into the cavity to form
a pre-
filled sealed container, typically containing liquid for a single dose to be
delivered. Although
possible to fill the container cavity through the container opening, e.g.
through a needle, the
preferred way is to fill the cavity from the rear side of front wall before
attachment of the rear
wall. A useful procedure is then to adhere the sealing film over the opening
or openings, pos-
sibly under welding action, filling liquid into the container cavity from the
rear side and ad-
hering the rear wall over the filled cavity, again possibly under welding
action. Preferably
these steps are made in the order mentioned. The invention contributes in
several ways to the
efficiency and simplicity of such a procedure, particularly in contrast to
blister type manufac-
ture and filling. In contrast to blister bulbs, flat sheets type materials can
be used for the seal-
ing film and the rear wall, allowing flat or single-curved adherence with
equally simple flat or
roll type tools and allowing adherence over several containers in multiple
container structures
and no stretch or other material deformation steps are necessary. Adapted
welding action, e.g.
heat, is applied individually to the sealing film and the rear wall
respectively and directly to
the adhering materials involved, whereas in blister manufacture sealing heat
for front and rear
materials has to be applied through a peel layer, over-adhering the peel
layer, prolonging the
process, possibly affecting the liquid present, and increasing product
tolerances.
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12
A delivery or dispenser device for ejection of the liquid from the containers
can gener-
ally be said to comprise a housing with a seat for the container or container
structure, a ram
movable in relation to the housing in a direction substantially axial to the
container when in
the seat, an actuator arrangement operative to drive the ram.
The housing shall be understood in broad sense and may take a variety of
forms. The
device housing represents the point of reference for the container position
and the movements
described, such as the ram used for collapse of the container rear wall and
for forces applied
by actuating means performing said movements, whereat the force is applied
between the
housing and the moving part. The minimum functional requirement is that the
housing offers
a support or platform for the container and movable parts and the actuating
means providing
the movements and forces. As in common practice, however, it is preferred that
the housing
forms a container at least partly embracing the parts and preferably also to
such an extent that
only the features designed to be controlled or monitored by the operator are
externally ex-
posed, to give an overall convenient design to use.
The housing should contain a seat for a container or several containers, the
minimum
requirements on which is that at least the container to be emptied is kept
fixed in relation to
the ram, preferably so that the container axis and the movement axis for the
ram are parallel
and most preferably coaxial with respect to the ram part to hit the container
rear wall. Prefera-
bly the seat should be able to accommodate containers with the characteristics
described
herein, e.g. with the shapes and sizes exemplified. The seat preferably
supports the container
against forward forces from the ram and preferably also against some rearward
and lateral
forces. The seat preferably allows the entire rear wall surface over the
cavity to be exposed to
the ram and should also expose at least the opening or openings on the front
side of the con-
tainer not to obstruct the liquid stream, although the rigidity of the present
containers do not
require any heavy support. Preferably the seat is also designed to allow easy
exchange of dis
crete containers, or sequential movement of the individual containers of a
mufti-container
structure, into the active position of the seat, e.g. by having a track in
which the structure can
be moved in one or two dimensions. In the preferred embodiment of containers
placed in a
circle, preferably on a disc shaped structure, it is suitable to rotate the
disc around a central
disc axis to bring the containers into alignment with the active position, in
a revolver type
manner. For single and in particular multiple container arrangements it is
desirable that guid-
CA 02379945 2002-O1-23
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13
ing arrangements are provided to secure good alignment with the ram axis in
order to reach
high delivery precision intended, e.g. structures provided in connection with
each container on
the package for cooperation with at least one corresponding locking structure
on the housing,
seat or preferably ram, arranged for interlocking at proper alignment. Locking
therebetween
can with preference be associated with a signal to assist stop in correct
position, e.g. tactile or
audible signal in manual operation or a mechanical or electronically
detectable signal in
automatic operation. Additionally it is preferred to include a counting
arrangement, again
manual or automatic, mechanical or electronical, designed to keep track on the
number of
containers used or remaining and warning for or preventing reuse of already
emptied contain-
ers.
The ram may include a ram head and piston arrangement for moving the ram head
along the movement axis. Although it is possible to design the ram head non-
congruent with
the container cavity, e.g. for use with different cavity shapes or when
relying on rear wall
stretch properties for emptying, it is preferred to design it for complete
fill-out of the cavity.
I S This can be done with a soft and adaptable ram head, e.g. for the purposes
of being compati-
ble with different cavity forms, to increase operation range or to obtain a
certain emptying
pattern, preferably to squeeze out the liquid from the peripheral cavity parts
towards the cen-
tral, axial, parts which can be done for example by making the soft ram head
slightly shal-
lower in shape than the shape of the cavity vessel form. For a single cavity
form it is, how-
ever, preferred to make the ram head front surface substantially identical
with the inner cavity
surface or, expressed in another way, the rear surface of the front wall in
the container space.
The ram head can be surrounded by a support, e.g. a tube structure in which
the ram head
travels, which is preferably also abutted around the cavity to seal the space
between ram head
and cavity at least during the rear wall collapse movement, e.g. to allow high
pressures or re-
duce leakage risks. The piston part of the ram is generally not critical to
the dynamics of the
ejection but rather for propulsion and will be described in connection with
the actuator sys-
tem.
The ram can be propelled by use of a variety of mechanisms and energy sources.
The
mechanism can be operated directly with manual energy, in which case, however,
it is pre-
ferred to provide an leverage or gear exchange to amplify or transform force
or speed, pref
erably towards lower speed and higher force. In order to have controlled and
consistent results
CA 02379945 2002-O1-23
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14
it is generally preferred to have automatic function in the sense that after
operator triggering
the propulsion takes place automatically, and preferably irreversibly, by use
of stored energy.
The energy may be stored in any way, e.g. in a mechanical spring, a gas spring
or gas genera-
tor, as electrical energy or a combination thereof. The energy may be
transmitted to the ram
by suitable motor or transmission means, e.g. electric motor or solenoid type
motor for elec-
trical energy, a piston and cylinder arrangement for gas springs or gas
generators and rotation
axis or plunger for coiled and helical springs respectively. It is generally
preferred to include a
transmission between the motor means and the ram proper, among other to
provide a force
amplification, e.g. by use of a gear wheel or a cam surface type of
transmission. It is preferred
that at least the ram head, and preferably parts of the ram piston, are
prevented from rotation
during forward movement, which can be secured by any known guiding structures,
such as a
non rotation symmetric part cooperation with a complementary part, the parts
being posi-
tioned on ram and housing respectively. A preferred transmission component for
propulsion
of the ram is a screw and nut arrangement, one of which is positioned on the
ram and the other
1 S on the motor side of the transmission. The necessary speed, force and
movement characteris-
tics for the ram depends on a number of conditions, such as the nature of the
container parts
and opening, the particular application implementation, e.g. surface or
penetrative delivery,
the viscosity of the preparation, e.g. aqueous solutions or ointments, etc.
and general state-
ments cannot be given. However, the energy sources, motor means and
transmissions exem-
plified can be adapted to each need. It has also been found beneficial to
include a damper, e.g.
a dash pot, a linear damper, a flow valve, a magnetic damper etc., to control
speed with
maintained stable force. In most applications it is desirable to have a rapid
rise and fall of
pressure, generally requiring a stable and non-retarded speed of the ram,
which is facilitated
e.g. by a damper or high inertia in ram and transmission.
It is also preferred to include in the device arrangements to facilitate
breakage or re-
moval of the temporary seal over the openings as described. Although it is
possible to break a
seal by the pressure itself generated when collapsing the rear wall it is
preferred to use an ac-
tive step to break the seal. This can be done by having a de-sealing tool
arranged in connec-
tion with the housing, e.g. a penetrating tool for a rupturable sealing or a
wedging or drawing
arrangement for removal of peelable sealing films. Such arrangements can be
located at or
close to the seat, e.g. to allow late action, or remote, e.g. if the seat area
is crowded. The de-
CA 02379945 2002-O1-23
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sealing tool can be operated manually or automatically or compulsory, e.g. as
a part of the
movement of container into the seat site. It has been found beneficial,
however, to position the
de-sealing tool on the rear side of the container for movement from rear to
front, which allows
the de-sealing tool to attack the film in the best manner possible, i.e. on
the film rear side to
5 lift it from the front wall front surface. It also allows the de-sealing
tool and mechanism to be
arranged more conveniently within the housing and to the rear of the container
for less inter-
ference with the ejection area and ejection target. The tool can have a
movement mechanism
of its own but most preferably the tool is arranged on or in connection with
the ram in such a
manner that it moves together with the ram, utilizing the same movement
mechanism and
10 facilitating a removal immediately before ejection and as an unavoidable
part of the ejection
procedure. Preferably the de-sealing tool passes though an opening in the
front wall structure,
and possibly also through the rear wall, at a location not occupied by the
container cavity but
covered by the sealing film. With preference the dimensions of such an opening
and the de-
sealing tool can be mutually adapted so as to act as a guiding arrangement, as
described, for
I S final alignment of ram and cavity before activation. In operation the tool
first lifts the film
from the container opening and the ram head then hits the container rear wall.
It is possible to
perform these two steps in a single continuous movement for the ram, e.g. for
simplest opera-
tion and latest possible de-sealing, or in a two-step operation, possibly
requiring two trigger-
ing actions from the user, e.g. in order to enable the user to verify that the
film has been prop-
erly removed. It might also be of interest to use different movements
characteristics for the
two steps, e.g. a slow movement for the peel not to cause tearing or rupture
and a fast action
for ejection, which might require some shift arrangement, e.g. a gear shift,
de-coupling of
brake or damper etc. The general container design principles of the present
invention strongly
amplifies the above described advantages, among other by having a rigidity
permittig front
wall use for guiding purposes and allowing areas outside the cavity part to be
utilized without
instability problems.
Depending on each application it may also be beneficial to equip the device
with
means assisting targeting and positioning. For example, when used for shooting
liquid to the
eye the device front with a cowling, eye piece or eye cup for abutment to the
eye socket.
Penetrating applications may require small distance or direct contact between
opening and
target surface whereas larger surface treatment may require an end piece
defining both an an-
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16
gle and a distance. As know per se for dispenser devices in general the device
may also in-
chide mechanical or electronic warning, alerting or timing means.
As indicated in the introduction the invention described herein may be used
for a vari-
ety of purposes within and beyond the medical area and for any type of
preparations, such as
chemicals, compositions or mixtures, in any container and delivered for any
purpose. It may
be used for liquids within a broad range of compositions, e.g. pure liquids,
solutions, emul-
sions, dispersions, body fluids etc., and viscosities e.g. high viscosity
ointments. For reasons
outlined the system has certain special values in connection with medical
delivery devices
where also the design constraints are more severe than in most other
applications. For con-
venience the invention has been described in terms of this application.
A preferred use of the invention is in connection with ophthalmic treatment of
the eye
with medical. The common administration manner is by eye drops or ointments,
however,
having several disadvantages. Both methods generally delivers a substantially
higher amount
than can be absorbed by the eye, not only resulting in dosing uncertainty and
loss of expen-
sive treatment medical but also in potential side-effects when non-absorbed
preparation is
drained away via the nasolacrimal duct, e.g. beta-blocking agents used in eye
treatment has
substantial systemic effects. Another problem is that the common
administration methods
tend to induce a blink reflex that may entirely destroy the treatment or at
least introduce a high
degree of uncertainty. Also the common methods do not provide an high degree
of targeting
precision, e.g. ability to hit the iris part of the eye being the penetrable
part of the eye for
prostaglandin. The principles used for the present invention solves these
problems, among
others by the possibility to deliver small amounts of liquid, actively ejected
and not deter-
mined by liquid surface tension, by the possibility of delivering the liquid
with sufficient
speed to beat the blink reflex and by the possibility to eject a concentrated
and coherent
stream for precise targeting. Typical parameters for this application will be
given below al-
though the invention shall not be regarded as limited to any such exemplified
parameter. A
typical single dose volume for delivery to the eye can be less than 25
microliter, preferably
less than 15 and most preferably less than 10 microliter. Generally the volume
is at least l,
preferably at least 2 and most preferably at least 3 microliter. Since it is
desirable that each
container contains a single unit dose, these figures also relate to the liquid
volume charged
and contained in the containers, possibly allowing for some overfilling to
compensate for non-
CA 02379945 2002-O1-23
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17
ejectable amounts, such as liquid remaining as wetting film or in the
container opening duct,
e.g. 25% but preferably no more than 10% overfilling. In addition to the
liquid the container
may contain other material, notably gas such as air or a purging gas such as
nitrogen or noble
gases, e.g. to facilitate manufacture, assist in atomizing or act as pressure
buffer, although in
many instances little or no gas need to be present. The container can for
example have a
maximum cavity diameter is about 1 to 20 mm, preferably between 2 and 10 mm,
calculated
as a circle equivalent surface if the cavity is not round. A suitable speed
for the stream of
drops or jet ejected should be a balance between on one hand enough linear
momentum to
traverse an air gap between opening and target, without gravity assistance,
and to travel fast
enough not be obstructed by blinking and on the other hand not so fast as to
cause inconven-
ient sensible impact on the eye. The ideal speed is to some extent dependent
on the drop size
used but as a general rule the drops should be able to traverse at least 1 cm,
preferably at least
3 and most preferably at least 5 cm through air by own momentum, incorporating
reasonable
distances between opening and target. A suitable lower speed limit when
leaving the opening
is l, m/s, preferably at least 5 m/s and most preferably at least 10 m/s.
Generally the speed is
lower than 200 m/s and preferably lower than 100 m/s. A suitable drop size so
defined should
be sufficient not to be retarded too quickly and not to be easily redirected,
e.g. to be inhaled,
and preferably has a minimum diameter of 20 micron, preferably not less than
50 micron and
most preferably at least 100 microns. Normally the size is less than 2000
micron and prefera-
bly less than 1 S00 micron. The stream may take the form of a shower or spray
of atomized
liquid droplets but preferably the stream is narrow and fairly coherent
although even such a
stream tend to break up into individual droplets after a certain time of
distance. The above
given values are intended to relate to spherical droplets and for multiple
droplets to the weight
average of particle diameters. A coherent stream tend to break up into
droplets of a diameter
of roughly double the diameter of the stream. Accordingly suitable opening
diameters for the
containers are about half the above given drop diameters or roughly between 10
and 1000
microns, preferably between 20 and 800 microns. A suitable front wall
thickness, from front
of opening to rear wall, may range from 0,5 mm to 10 mm and preferably between
1 and 5
mm. The above considerations are fairly independent of liquid viscosity and
tend to apply
both for solutions and ointments.
Summary of drawings
CA 02379945 2002-O1-23
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18
Figures 1A to 1G illustrates schematically in section various container
designs and
features useful in single or multiple container arrangements
Figure 2A, 2B and 2C show in rear flat view, diametrical section and enlarged
detail a
multiple container structure in disc form, having 14 containers distributed
around the disc
periphery.
Figure 3A to 3D depicts a similar disc as in Figure 2 in perspective views and
partial
sections, showing also rear wall and peel film.
Figure 4A and 4B shows in partial section and perspective view respectively
the inter-
nal parts of a dispeser device for disc type multiple containers.
Description of drawings
In Figure 1 all embodiments, except that depicted in figure 1 F, the front
wall is formed
from a plate type structure, being either flat as in Figures 1 A, 1 B, 1 D and
1 E or curved with
concentric surfaces as in Figures 1 C and 1 G. The Figures illustrates various
useful features
but, for clarity, not all necessary or preferred details are shown in all
Figures.
In Figure 1A the container 110 comprises the front wall 111, having a front
surface
and a rear surface being substantially parallel. The front wall 111 has a
cavity 112 in the form
of a vessel with an front vessel surface 113 and an opposite rear opening 114.
The cavity
cross-section shown has the general form of a circle segment. An opening 115,
defining a
container axis 116, provides a fluid connection between the cavity interior
and the exterior at
the front wall front side. The opening 115 is here shown as a substantially
constant cross-
section channel with a thin inner membrane 117, formed from material left at
injection mold-
ing and acting as a temporary seal to be broken at cavity pressurization. A
deformable rear
wall 118 covers the rear opening 114 of the cavity vessel with a seal (not
shown). The rear
wall is formed from an originally flat sheet material, here shown with
discontinuous curvature
in the form of a number of folds 119, running perpendicular to the Figure
plane, the folds
acting to reduce the necessary stretching of the rear wall material when
forced into the con-
tainer cavity.
Figure 1 B shows a container 120 similarly designed as in Figure 1 A except
that the
opening 125 is shown slightly convergent and is covered on the front wall
front surface by a
temporary seal in the form of a rupturable or peelable sheet 127, sealed to
the front surface of
the front wall. The rear wall 128 is here shown as a film with a continuous
curvature part 129,
CA 02379945 2002-O1-23
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19
providing an additional volume over that provided by the vessel when limited
by the rear ves-
sel opening 124, here illustrated with a dotted line flush with front wall
rear surface, and also
adding surface to the rear wall limiting stretching thereof. The curvature of
rear wall part 129
can be formed from a flat sheet material if the curvature is constant normal
to the Figure
plane, as for a cylinder mantle surface, but need a double-curved material if
in the form of a
bulb.
Figure 1 C illustrates a container 130 formed in a front wall 131 basically in
the form
of a cylinder part with single-curved front and rear surfaces centered around
a cylinder axis
133 and with an opening 135 on the cylinder exterior, convex, surface. Also
illustrated is a
cavity 132, having a cylindrical part 134 terminating in a sphere segment part
137, both parts
symmetrically centered around opening 135 axis 136. Rear wall 138 is formed
from a single-
curved material continuously curved to adapt to the cylindrical inner surface
of the front wall
131, hereby being larger in surface than a corresponding flat sheet over the
cavity vessel
opening, illustrated by dotted line 139.
Figure 1 D illustrates a container 140 with a front wall 141 having a cavity
142 the
vessel surface of which has a cylindrical part 143 and a flat bottom part 144.
Also illustrated
is an opening 145 with a surrounding recess 146 on the front wall front
surface, serving to
avoid direct contact between the opening proper and a peel film 147 and its
sealing surface
148, which is arranged in a ring outside the recess 146.
Figure 1E schematically illustrates a container 150 with a cavity in the form
of a circle
segment, as in Figures 1 A and 1 B, centered around circle midpoint 153.
Construction radii
lines 154 drawn from point 153 intersects the inner surface 155 of the cavity
152 vessel per-
pendicularly and the Figure illustrates that the wall thickness, when measured
along these
construction lines normal to the vessel surface, increases (solid parts of
lines 154) when
moving laterally away from the cavity axis 156. In contrast, Figure 1 F
illustrates a container
160 embodiment wherein the cavity 162 is formed in a front wall 161 design
giving a constant
wall thickness when measures along construction lines 164 centered in point
163 in the same
manner as in Figure 1 E. This Figure also illustrates a longer opening 165
duct, having a con-
vergent part I 66 and a straight part 167 with roughly constant cross-section.
For clarity, sec-
tinning lines have been omitted in these Figures.
CA 02379945 2002-O1-23
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Figure 1 G illustrates a container 170 formed in a front wall 171 basically in
the form
of a cylinder part, as in Figure 1 C, with single-curved front and rear
surfaces centered around
a cylinder axis 173. However, in this embodiment the opening 175 is arranged
on the cylinder
interior, concave, surface. Rear wall 178 is formed from a single-curved
material continuously
5 curved to adapt to the cylindrical outer surface of the front wall 171,
hereby again being larger
in surface than a corresponding flat sheet over the cavity 172 vessel. Also a
temporary seal
film 177, covering the opening 175, is formed from a single-curved sheet
material.
All container embodiments illustrated in Figure 1 A to 1 G can be used as
single dis-
crete containers or can be part of multiple container structures by being
joined with similar or
10 different container types, indicated by undefined lateral continuations of
the front walls illus-
trated.
Figure 2A, 2B and 2C show in rear flat view, diametrical section and enlarged
detail a
multiple container front wall structure in disc form, having 14 containers
distributed around
the disc periphery. The disc, generally designated 200, can be said to include
a peripheral
15 front wall structure 210 with the containers, a slightly offset central
auxiliary part 230 with
actuating and holding arrangements and a transition part 250 with peeling and
guiding ar-
rangements. In the embodiment shown the plate like basic shape of the front
wall structure
210 has a front side 211 and a rear side 212 and comprises 14 identical
cavities 220 in the
general form of circle segments, the rear rim 221 of which are slightly
rounded. The cavity
20 openings 222 are slightly convergent and on the front side 211 of the front
wall structure 210
a small recess 223 is provided for reasons earlier outlined. The auxiliary
part 230 can be said
to include a central axis hole 231 for bearing and actuation purposes with a
keying surface
232 providing non-rotational symmetry to facilitate actuation. The hole 231
preferably is
slightly conical and converging from rear to front in order to facilitate
actuator insertion and
centering. Spacing ridges 233 serve to provide a gap between discs when
stacked, e.g. in ster-
ilization. The transition part 250 can be said to include bores 251, also
slightly converging
towards the front, serving to allow penetration of a de-sealing tool from the
rear side towards
the front side to lift off a temporary seal in the form of a peel film (not
shown), the coopera-
tion between the tool and the bore also acting as a guiding arrangement,
centering the cavity
with respect to a ram head of a dispenser device. With the cavity arrangement
shown a flat
rear wall film (not shown) can be positioned over the cavity rear sides to
seal the containers,
CA 02379945 2002-O1-23
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21
e.g. after filling. Each cavity can be sealed with individual film parts but
it is also possible to
use a single sheet for covering all cavities. Preferably such films are
radially restricted to the
front wall part 210 of the disc, leaving the transition part 250 and the
auxiliary part 230 un-
covered. A typical overall thickness of the front wall plate can be about 2 mm
with a cavity
depth of about 1.5 mm.
Figure 3A to 3D shows a similar disc arrangement as in Figure 2. Figure 3A is
a per-
spective view of the disc front side, Figure 3B a perspective view of the rear
side, Figure 3C a
section from disc periphery to center through a cavity before ejection and
Figure 3D a similar
section of the cavity after use. As in Figure 2 the disc has a peripheral
front wall structure 310
with the containers, a slightly laterally offset central auxiliary part 330
with actuating and
holding arrangements and a transition part 350 with peeling and guiding
arrangements. All
details common with Figure 2 will not be repeated. Also in this embodiment
there are 14
identical cavities 320 in the general form of circle segments with cavity
openings 322 with a
front side recess 323. Holes 311 serves to facilitate handling of the disc,
e.g. during manufac-
ture and filling. The auxiliary part 330 here has a central axis hole 331 for
bearing and actua-
tion purposes with 14 symmetrically arranged teeth 332, allowing the disc to
be attached to an
correspondingly toothed actuating axis of a dispenser device without
consideration to the po-
sitioning of any individual container or disc part. The transition part 350
has bores 351, serv-
ing to allow penetration of a de-sealing tool from the rear side towards the
front side to lift off
a temporary seal in the form of a peel film to be described. A single flat
rear wall film 370, cut
into ring form, radially restricted to the front wall structure 310, covers
all the cavity rear
sides to seal the containers. As best seen in Figure 3A a peelable film 390 is
attached to the
disc front side so as to cover all cavity openings 322. The peel film is
formed in star form
from a single flat sheet and comprises a unifying central ring part 391,
concentric attached to
the auxiliary disc part 330, from which ring part tongues 392 radiate, one for
each cavity, so
as to pass over the transition part 350 under covering of the bores 351 and
further radially out
to cover the cavity openings 322. Initially all cavity openings 322 are
covered by the tongues
392. When the liquid from one of the container is to be dispensed a de-sealing
tool (not
shown) is moved through the corresponding bore 351 from the disc rear side
towards the front
side, hereby lifting the corresponding tongue 392' to free and expose the
corresponding cavity
opening 322, as best seen in Figure 3A and 3D. The container content is then
ejected by forc
CA 02379945 2002-O1-23
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22
ing the rear wall 370 under stretching from the flat condition shown in Figure
3C to the cavity
filling condition shown in Figure 3D.
Figure 4A and 4B illustrates a dispenser device for multiple container discs
as de-
scribed in relation to Figure 3. The device, generally designated 400, is
shown without any
casing part of the housing. The device receives the disc 410 at its front
side, to the right in the
drawings. The device can be said to include a seat 420 for the disc
incorporating a disc bear-
ing axis 421, having teeth 422 corresponding to the teeth of disc central
opening. The axis 421
has a bearing gear wheel 423 cooperating with a control gear wheel 424
connected to a thumb
wheel 425 for sequential advancement of the individual containers into the
ejection position to
be described. The thumb wheel can be actuated manually or a may be connected
to a mecha-
nism (not shown) for automatic incrementation in connection with the motor
actuation cycle.
A pawl and ratchet mechanism 426 secures that the disc occupies predetermined
positions
only and that it can be rotated in one direction only to avoid reuse of
already emptied contain-
ers. These parts may also include counting means or other assistance (not
shown) to urge for
disc replacement. In the Figures the lowermost disc part is in the active
ejection position 427
where the seat may comprise additional support or guidance (not shown) for the
disc, e.g. to
against forward and possibly rearward movement for example to balance force
from the ram.
Preferably such support structures can be arranged on a door arrangement of
the housing for
inserting the disc. In this position the cavity is centered with respect to
the ram, generally
designated 430. The ram includes a ram head 431 with a circle segment front
form, adapted to
the container cavity form. The ram head is part of a ram head support 432,
also carrying a de-
sealing and guiding tool in the form of a probe pin 433, arranged to penetrate
bores, corre-
sponding to the bores 351 in Figure 3, in the disc 410 for the described
purpose of lifting a
temporary seal film from the container opening and of centering and
stabilizing the container
cavity with respect to the ram head 431. Probe pin 433 extends farther in the
forward direction
than ram head 431 in order to perform the above functions before the ram head
hits the rear
wall of the container. The ram further comprises an external screw-thread 434
for propelling
the ram axially forwards and rearwards. The ram is keyed against rotational
movements by
guidance (not shown) of the ram head support 432 flat lower surface 435. The
device further
comprises a motor and transmission system, generally designated 450 for
actuation of the ram
movements. A rotationally arranged but axially stationary drive nut 451 has an
internal screw-
CA 02379945 2002-O1-23
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23
thread 452 for cooperation with ram external screw-thread 434 so as to move
the ram axially
at rotation of the drive nut. An angular viscous damper 453 has a stationary
part 454 and a
rotational part 455, connected to the drive nut 451 so as to rotate with the
drive nut. The drive
nut 451 has external gear teeth 456 by which the drive nut can be rotated. A
rotationally ar-
ranged motor housing 460 has an external gear 461 of larger diameter than the
drive nut 456.
Inside motor housing 460 is arranged a motor spring 462, which can be cocked
by rotation via
a winding axis (not shown) entering trough the open part 463, to the left in
the drawings, of
the motor housing 460. Rigidly attached to the motor housing 460 and
concentric therewith is
a catch wheel 464 with a rim groove 465 for cooperation with an arming pin 466
of a manu-
ally accessible safety switch 467. A fire system 470 incorporates a release
system (not shown)
with a fire button 471 having two activation positions, a first partial
operation of the fire but-
ton allowing the motor and transmission system 450 to advance the ram to move
the probe pin
433 into to completed removal of the temporary seal film, but with no contact
between con-
tainer rear wall and ram head 431, and a second operation of the fire button
471 allowing the
ram head 431 to complete its forward movement into the container cavity, as
shown in the
Figure. A typical propulsion speed for the ram during ejection can be for
example about 2 mm
movement performed during a time of about 50 msek, for a cavity depth of about
1.5 mm.
The invention is not limited to the embodiments described and exemplified but
can be
varied within the terms of the appended patent claims.
