Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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Method for producing a beverage-ingredient capsule for the preparation of a
beverage and apparatus
The present invention relates to the manufacturing of a beverage-ingredient
capsule
used for preparing a beverage in a beverage producing device, such as a coffee
machine. The method also relates to an apparatus for implementing the method.
Beverage producing systems have been developed for many years on the basis of
portioned beverages, in particular, capsules containing a predetermined dose
of
beverage ingredient such as coffee, tea, milk powder and the like. The
numerous
advantages of such systems have been widely recognized, in particular, their
convenience of use, clean operations and better controlled quality of the
brewed
beverage delivered.
The term "capsule" is here used to designate packets, pods or cartridges as
well,
comprising in general a mass of ingredient and an outer (removable or non-
removable)
package.
Capsules such as coffee pods, wherein the ingredient is compacted therein, are
known,
for example, in EP0602203B1. The capsule can take the form of a flexible
sachet
containing individual portions of ingredient powder, e.g., coffee, tea,
soluble coffee,
etc. The ingredient powder is compacted to form a solid cake of powder. The
compacted cake of powder is sealed in a gastight package formed of two
flexible foils
of circular, oval or polygonal shape. When hot water is injected through one
of the
two foils, the opposite foil is opened under the effect of the increase of the
fluid
pressure inside the capsule, such as against perforating elements of a capsule
holder of
the beverage preparation device. Other extraction principles also encompass
capsules
which open solely under the effect of inside pressure or pre-opened before
insertion in
the device.
A capsule with a cake of compacted ingredients therein provides advantages
over a
capsule with loose ingredients therein. In particular, a smaller capsule can
be
produced for providing a similar quality of beverage, e.g., liquid coffee
extract.
Therefore, the capsule uses less packaging material and provides a reduced
volume of
waste after brewing. They can be more conveniently and more economically
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packaged in large packs, e.g., in cardboard containers or flow wrap bags, to
reduce
shipment costs and storage space.
Co-pending European patent application No. 09164590.3 relates to a capsule for
the
preparation of a beverage comprising a first and second covering wall (e.g.,
foil)
connected at a peripheral seam for forming an internal cavity containing a
beverage
ingredient and a contactless identifying element for identifying the capsule
by
detecting means of a beverage producing device, wherein the identifying
element is
placed inside the ingredient powder. In particular, the identifying element
can be an
insert embedding glass-coated metal-alloy wire(s) providing magnetic
characteristics.
This invention proposes a capsule detecting solution, e.g., that provides more
freedom
on the design of the capsule, ensures a more reliable signal detection and is
less prone
to damage or deterioration of the identifier, e.g., during handling of the
capsule.
Another co-pending European patent application No. 09164586.1 relates to a
capsule
wherein the identifying insert is oriented along its longest dimension
substantially
orthogonally relative to the transversal plane passing along the seam of the
capsule.
Therefore, there is a need for producing a capsule with an insert, such as an
identification element, precisely and reliably positioned in the compacted
mass of
ingredient.
There is also a need for producing the capsule, in particular, the compacted
mass or
cake, at quick pace on the manufacturing line. One problem of positioning an
insert in
a compacted mass of powder comes from the ability to place the insert in a
precisely
defined position but also the ability to maintain this insert in this position
during all
the steps of production. Furthermore, the insert should not move in the
capsule after
its manufacturing, i.e., before or during its use in the beverage machine. In
case the
insert would be an identification element as in co-pending patent applications
No.
09164590.3 and No. 09164586.1, a deviation of the position of the insert in
the
capsule would potentially lead to problems of detection of the insert by the
detecting
means of the beverage producing device or other control devices.
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The present invention now fulfils these needs and resolves essentially all
these
problems.
For this, the invention relates to a method according to the appended
independent
claim(s). Additional characteristics of the method and apparatus are present
in the
appended dependent claims.
More particularly, the invention relates to a method for producing a beverage-
ingredient capsule for the preparation of a beverage; the method comprising
the steps
of:
providing a mould cavity,
at least partially filling a mould cavity with the beverage ingredient in
powdered or particulate form,
compacting the powdered or particulate beverage ingredient in the mould
cavity to obtain a compacted mass of the beverage ingredient,
forming at least one recess in the compacted mass and,
inserting a capsule identification insert into the said recess.
In a mode, the recess is formed while the mass of powdered or particulate
beverage
ingredient is being compacted.
According to the method of the invention, the forming of the recess is
facilitated. Also
the dimensions and shape of the recess are better geometrically defined. Also,
the
walls of the recess become more compact, thereby more solid and less crumbly.
As a
result, the insert can be well positioned and its position is more reliable
and less
subject to deviation or alteration during placing and/or once the insert is in
place.
In an embodiment, the filling step is carried out in a single filling
operation with the
entire amount of powdered or particulate beverage ingredient mass required for
the
capsule.
The filling of the mould cavity can be done in more than one operation.
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In another mode, the mould cavity is filled with less than the entire amount
of
powdered or particulate beverage ingredient required for the capsule before
inserting
the insert and thereafter feeding into the mould cavity the remainder of the
required
amount of powdered or particulate beverage ingredient for the capsule and
further
compacting the mass. In this embodiment, the mould cavity is filled with a
partial
mass of powdered or particulate ingredient before insertion of the insert and
the
mould cavity is filled with the remainder mass after insertion of the insert.
In a mode, the step of insertion of the insert is carried out after a recess
dedicated for
the insert has been formed. For example, once the compaction of the ingredient
powder is finished, a recess is left open in the compacted mass which enables
placement of the insert therein. Since the mass is compacted, the recess has
walls, e.g.,
bottom end and tubular sidewalls that offer a relatively solid support for the
insert
thereby ensuring a correct and reliable position.
In another mode, the recess is formed by the insert itself preferably during
its
insertion in the mass of powdered or particulate ingredient. In this mode, the
operation is simplified by the use of the insert for forming the recess.
Furthermore, the
operation can also comprise leaving the insert in place in the recess once it
is formed
by the insert.
In a method, the compacting step and the recess forming step are effected by
pressing
an outer shape forming surface and a recess forming surface against the mass
of
powdered or particulate beverage ingredient.
More preferably, the outer shape forming surface and the recess forming
surfaces are
both part of a portion of a mould, e.g., a half-mould; such that both surfaces
are
connected in such a manner that the two operations applied on the mass of
powdered
or particulate ingredient are carried out substantially during a single
pressing stroke
applied by the portion of mould, e.g., half-mould, onto the powder.
In a preferred mode, the recess is formed in the central region of the mass of
powdered or particulate beverage ingredient. The central location of the
recess is
preferred for many different reasons. The recess in the centre of the mass
provides
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reduced risks of damaging the mass and a potentially stronger recess for
receiving the
insert. The insert is also better protected in the centre of the capsule
inasmuch as
potentially a greater mass of powdered or particulate ingredient surrounds the
insert
and prevents it from moving in the mass when compacted.
In a particular mode, the outer shape forming surface and recess forming
surface are
formed in an upper mould part. The upper mould part is preferably moved
relatively
to a lower mould part containing the powder mass, in the manner of a piston
stroke,
for providing powder compaction and for forming the recess at the same time.
The
external form, e.g. of the upper mould part, complementary fits in the cavity
of the
lower mould part causing the reduction of the size of the cavity during the
stroke and
consequently, compaction of the mass of powder contained therein.
The control of the compaction of the powder mass is generally made by
determining
the quantity of powdered or particulate ingredient filled in the cavity and by
controlling the reduced size of the cavity left by the stroke between the two
mould
parts. Therefore, a constant compaction is generally obtained by maintaining
the
quantity of powder and reduced size of the cavity constant; all other possible
relevant
parameters (e.g., powder grind size, type of powder, etc.) being equal.
Preferably, no subsequent compacting step is necessary after said stroke.
However, it
can also be possible that a later compacting step of the mass of powdered or
particulate ingredient and/or of capsule itself containing said ingredient, is
carried out
by a second stroke to complete the compaction desired or when an additional
filling
operation is necessary to complete the content of the final mass of powder
desired for
the capsule.
The compaction of the (partial or full) mass of powder is usually such that
the
powdered or particulate ingredient, e.g., coffee cake, forms a relatively
handleable
and solid piece with limited crumbliness.
The recess can be formed in any suitable location(s) of the mass of powdered
or
particulate beverage ingredient. Also more than one recess can be formed at
the same
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time in different locations of the mass. More preferably, the recess is formed
in the
central region of the mass of powdered or particulate beverage ingredient.
In the preferred method, the recess is formed with a flared opening. Such
opening
configuration of the recess takes into account the tolerance of positioning of
the insert
by the insert positioning device (at the operational positioning speed), e.g.,
an insert
feeder.
Preferably, the insert is an elongate element. The insert can be an elongate
element
which ratio of length-to-diameter is comprised between 50:1 and 3:1.
Preferably, the
element is cylindrical or parallelepiped. More preferably, the insert is an
identification
element such as a magnetically responsive, inductive element or RFID element.
The insert has a cross-section which is substantially complementary to the
cross-
section of the recess. However, slight cross-sectional variation between the
insert and
the recess are tolerated such as if they can help anchoring the insert in the
powder.
The cross-section of the insert is preferably slightly larger than the cross
section of the
recess for tightening the insert in the recess and therefore avoiding the
insert to move
during the subsequent manufacturing operations of the capsule and during all
subsequent handling and use of the capsule. This size differential is also
useful for
taking into account the tolerances between the dimensions of the insert and
the
dimensions of the formed recess. For example, the element can be a small rigid
stick
of about 5-20 mm long and 0.5-3 mm large with its diameter being larger by
about
0.01 to 0.5 mm the diameter of the recess.
In a specific mode, the mass of powdered or particulate beverage ingredient is
compacted and formed in the moulding cavity to define two main opposed convex
surfaces and a truncated peripheral edge.
After the steps of compacting, forming the recess and inserting the insert are
completed, the compacted mass is removed from the mould cavity and loaded into
a
package comprising a first and second foils covering the respective main
surfaces and
the foils are sealed at a peripheral seam adjacent to the truncated peripheral
edge.
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The invention also relates to an apparatus for implementing the method, as
aforementioned, comprising at least a first mould part and at least a second
mould part
in opposed relation and relatively moveable toward and away of each other, at
least
one of said mould parts comprising recess-forming means for forming at least
one
recess in the mass of powdered or particulate beverage ingredient while the
mass is
compacted between the mould parts; said apparatus comprising recess means for
positioning an insert in the recess thus formed in the compacted mass of
powdered or
particulate beverage ingredient.
The apparatus may further comprise another mould part received around the
first and
second mould parts for defining a truncated peripheral edge of the compacted
mass of
powdered or particulate beverage ingredient.
The invention will be described in more detail in the description of the
figures that
follows.
Fig. 1 is a cross-section view of a capsule for the preparation of a beverage
including
an ingredient-powder cake and an identification insert embedded therein;
Fig. 2 is a schematic view of an apparatus for producing the ingredient-powder
cake
of the capsule of figure 1;
Figs. 3 to 9 illustrate a first embodiment of the process of forming the
powder cake
and placing the insert therein;
Figs. 3 show the beginning of filling the lower mould portion with ingredient
powder;
Fig. 4 shows the mould portion when filled with loose ingredient powder before
compaction;
Fig. 5 shows the punching step in the mould during the stroke;
Fig. 6 shows the powder cake with its recess after the punching step;
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Fig. 7 shows the handling of the insert in the apparatus for positioning it
within the
compacted cake;
Fig. 8 shows the positioning of the insert in the compacted cake;
Fig. 9 shows the compacted cake with its insert being properly placed;
Figs. 10 to 17 illustrate a second embodiment of the process of forming the
powder
cake and placing the insert therein;
Fig. 10 shows the beginning of the powder filling operation with a partial
mass of
powder in a lower mould portion with ingredient powder;
Fig. 11 shows the mould portion when filled with the partial mass of loose
powder
just before compaction;
Fig. 12 shows the compacted partial mass of powder after a first compaction
stroke,
Fig. 13 shows the positioning of the insert in the partial compacted mass;
Fig. 14 shows the second filling operation of the mould portion with the
remaining
mass of loose powder to complete the production of the powder cake;
Fig. 15 shows the mould portion full with powder and an insert therein just
before
compaction;
Fig. 16 shows the end of the second compaction of the mass of powder with the
insert
fully embedded therein during the second compaction stroke;
Fig. 17 shows the removal of the capsule from the lower mould.
In reference to figure 1, the capsule 1 of the invention forms a package
containing
ingredient-powder such as roast and ground coffee powder. The capsule can be
sized
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with powder suitable for preparing a beverage single or multi- serving. The
capsule
can be formed of a first foil 2 and a second foil 3 connected at a peripheral
seam 4 and
delimiting an internal cavity filled with ingredient. The capsule can (but not
necessarily) be designed symmetrically along a plane passing through seam 4.
The
two foils may be permeable or impermeable to the liquid. If impermeable to
liquid,
the foils 2, 3 can be opened, such as by perforating them, before or at the
time of use
in the beverage producing device or removed before insertion in the device.
The foils
may further be impermeable to gas when a gas barrier layer is present, e.g., a
layer of
thin aluminium and/or EVOH. The container may further comprise one or more
internal filter layer(s) such as paper filter(s) for instance. The two foils
may also be
formed entirely of filter layers such as a porous paper, porous plastic,
porous
aluminium and combinations thereof.
The two foils 2, 3 connect together at a seam 4 along a median transversal
plane P.
The seam can be produced by welding the two foils together in this region. In
a
preferred mode, the seam is preferably resistant to tearing and may be
reinforced by
additional layers such as cellulose (e.g. paper), polymeric fibres, plastic,
rubber and
the like. The foils can be flexible for facilitating forming during
manufacturing and
reducing the amount of packaging material. The foils can have an inner layer
made of
a layer compatible to sealing such as oriented polypropylene (OPP). The foil
may also
contain a decorative layer. In a preferred packaging configuration, each foil
is formed
of a multi-layer comprising the following layers (from exterior to interior):
PET/decorative layer /Adhesive/Aluminium/Adhesive/OPP. The aluminium layer has
preferably a thickness between 10 and 100 microns. The OPP (i.e., oriented
polypropylene) layer has a thickness of between 5 to 50 microns and the PET
layer
has a thickness of between 5 and 50 microns. The foils could also be formed of
filter
paper and a welding layer for the seam or a combination of aluminium, filter
paper
and/or plastic.
The connected foils 2, 3 delimit an internal cavity 5 which can be at least
partially
occupied by a powder cake 6 formed of compacted beverage ingredient. The
beverage
ingredient can be ground coffee, soluble coffee, leaf tea, soluble tea, cocoa,
milk,
chicory, herbal tea, an infant formula, culinary powder and combinations
thereof. In a
preferred embodiment, the ingredient contains essentially roast and ground
coffee
powder.
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The beverage ingredient is in compacted form such as resulting in a solid
powder cake.
The cake may form a lenticular section with a truncated peripheral edge 7
substantially axially oriented. As a result of the edge 7 being present, an
annular void
8 is created between the powder and the seam of the outer package. Such shape
is less
fragile after compaction and it facilitates welding of the foils at the seam.
Eventually,
the cavity may be placed under partial vacuum before sealing at the seam for
preventing the walls to deform outwardly due to gas release (e.g., C02) from
coffee
powder. The resulting general form of the capsule can be a symmetrical
lenticular
container of substantially convex surface on both sides. Of course, other
shapes of
capsule can be envisaged which are not symmetrical. For instance, the outer
package
of the capsule can comprise a cup-shaped body with a flange and a membrane
connected (e.g., welded) to the flange of the body.
An insert 9 is embedded, at least partially in the compacted cake. By
"partially
embedded", it is meant that more than 50% of the surface of the insert is
directly in
contact or in close vicinity with the powder without separation by the outer
packaging
material (e.g., foils). More preferably, the insert 9 is substantially fully
embedded in
the beverage ingredient. By substantially fully embedded, it means that at
least about
90% of the surface of the insert is directly in contact or in close vicinity
with the
powder without separation by the outer packaging material (e.g., foils). The
insert
can be an identifying element which is sensitive to physical excitation by or
from an
outside detecting device and/or providing a signal to an outside detecting
device such
as by magnetic effect, inductive effect or radio-waves. In a preferred mode,
the
identifying element is designed for enabling detection of the capsule in
presence of a
magnetic field produced by a magnetic-field producing device. By "magnetically-
responsive", it is here meant that, in a general manner, the identifying
element (or also
referred in short as: "identifier") has magnetic or ferromagnetic
characteristics
corresponding to its specific composition and identifiable, or at least
discriminable,
compared to another composition under the effect of magnetic flux provided by
electromagnetic detecting means (not shown). More particularly, the insert 9
comprises a protective sheath including one or more glass-coated metallic
wires such
as described in co-pending European patent application No. 09164590.3.
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Fig. 2 illustrates an apparatus for producing the ingredient-powder cake 6.
The
apparatus comprises a press 10 with a circular plate 11 including a series of
mould
portions 12 arranged in a circumferential pattern in the plate. The press is
designed to
produce a plurality of powder cakes at quick pace. The plate is controlled by
a control
and driving unit (not shown) to turn stepwise or in a continuous motion (in
rotational
direction A). The press further comprises a series of upper mould portions 13
wherein
each mould portion is arranged to reciprocate up and down relative to a lower
mould
portion (along axial direction B) and to engage in the lower mould portion 12
for
compaction of a powder cake. Preferably, each lower mould portion 12 is thus
associated with an upper mould portionl3 such that the upper and lower mould
portions 12, 13 are axially aligned (along axis D) and turn together along a
circular
path around a median vertical axis I of the plate and in direction of rotation
A shown.
In a known manner `per se', the relative axial movement of the upper mould
portions
13 is controlled by a cam path (not illustrated) forcing the portions up and
down as
they turn along axis I. As a possible alternative, the axial movement of the
mould
portions 13 could also driven by a mechanism using hydraulic pistons. The
press
further comprises a powder feeder 14 for feeding the lower mould portions 12
with
powder as the plate turns. The powder feeder extends across a portion of the
plate 11
in intersection of the lower moulds 12 and it is arranged to continuously feed
the
lower mould portions moving below it with powder. The press further comprises
an
insert feeder 15 for placing at least one insert in each of the powder cake
after
compaction.
Fig. 3 shows, in cross section, a detail of the press 10 during feeding of
powder in the
lower mould 12. As the plate 11 moves (e.g., turns) relative to the powder
feeder 14,
powder 16 falls into the mould portion 12 and progressively fills it. The
cavity 17 is
sized to be able to receive a predetermined quantity of powder (e.g., ground
coffee
powder) corresponding to the desired ingredient quantity in the final capsule.
When
the mould 12 has passed the powder feeder 14, its cavity is filled with the
proper
quantity of powder as illustrated in Fig. 4. The powder is loose in the cavity
and its
upper surface has been scraped by the front surface of the feeder by virtue of
the
relative movement of the mould portion relative to the powder feeding portion
14. It
should be noted by the way that the press could move in a linear relative
fashion
rather than in a rotary relative fashion as illustrated as a matter of
example.
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As shown in Fig. 5 in the next operation, the powder is compacted by the upper
mould
portion 13 lowering and engaging in the lower mould portion 12 in the manner
of a
piston-type press. The upper mould portion comprises an outer forming surface
18
that is designed to press one of the two extended sides of the compacted cake
whereas
the lower mould portion 12 comprises an outer forming surface 19 designed to
press
the other extended side. The surfaces 18 and 19 can also be of substantially
cup shape.
The surfaces 18 or 19 can be of relatively identical design when the resulting
capsule
is symmetrical. The degree of compaction of the powder cake is determined by
controlling the relative constant cavity's height, e.g., "D", between the two
moulds. In
general, the volume of the powder is reduced between 10 and 80% of its initial
volume in loose form in the mould. While the compact powder cake is being
formed,
at least one recess is being also formed by a recess forming surface 20 of the
mould
portion protruding downwards from the upper mould portion 13, i.e., from its
forming
surface 18. The recess forming surface thus forms, in general, at least one
protrusion
extending from the outer forming surface 18. For example, the protrusion 20
extends
vertically along the median axis of the cavity to provide a recess within the
mass of
powder in a position aligned with the centre I of the capsule (Fig. 1).
Thereby, as the
upper mould portion lowers in the cavity of the lower mould portion, the
recess in the
coffee powder is created while the coffee remains sufficiently loose, so that
the mass
of powder is still relatively soft to be introduced by the protrusion.
Furthermore, the
compaction by the upper mould 13 on the powder is exerted while the protrusion
20
remains in place in the coffee powder thereby solidifying the powder by
compaction
effect around the puncher. As a result, the recess is well dimensionally
defined and
the walls and edges delimiting the recess become relatively solid.
In an alternative, the recess can be formed by a recess forming means
protruding from
the lower mould portion 12. In this case, the upper forming mould portion 13
can be
formed as a concave forming surface 18 without the protrusion 20. The
protrusion is
thus affixed to the lower mould portion 12 and protrudes upwardly. In this
case, the
protrusion is preferably designed to produce a through-hole in the mass of
powder to
ensure an opening on the upper surface of the compacted mass enabling the
insertion
of the insert in the subsequent step. It can also be possible that both the
upper and
lower mould portions have a part of the protrusion.
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As illustrated in Fig. 6 after compaction, the upper mould portion 13 is
disengaged
from the lower mould portion 12 thereby leaving a recess 21 in the compacted
cake.
The recess 21 may be formed with a flared opening portion 22 of a few degrees
relative to the median axis I to take into account the precision tolerance
when
inserting the insert in the cake in the next operation of insertion.
Preferably, the angle
of the opening portion is of about 5-30 degrees relative to median axis I,
more
preferably of about 10 degrees. The recess may also be formed by a main
portion 23
of tubular or slightly conical shape (e.g., 1-7 degrees relative to median
axis I) to
prevent risks of breakage. Furthermore, the recess is preferably slightly
longer than
the length of the insert to be received in or at least of equal length. Also,
the main
portion 23 is preferably of slightly smaller cross-section than the insert to
ensure a
certain blocking effect on the insert and consequently prevent risk of
variation of its
localization once in place.
In the next operation shown in Fig. 7, the lower mould portion 12 is uncovered
thereby showing the compacted cake apparent with its empty recess 21. The
insert 9
intended to be placed in the cake, is handled by a pair of jaws 24 of the
insert feeder
15. The insert is lowered relatively to the compacted cake in axial direction
C causing
the insert to be introduced in the recess. The jaws handle the insert such
that a
sufficient free length "1" of the insert can be inserted in the recess while
the remaining
length of the insert is firmly held or pinched by the jaws. Preferably, the
free length
"1" represents at least 50 %, preferably at least 80 % of the total length of
the insert.
In the next step as shown in Fig. 8, the insert 9 is pushed in the recess to
take its final
position by a pusher 25 that exerts a pushing action at the opposite end of
the insert,
e.g., an axially and downwardly oriented pushing action. During the pushing
action,
the insert may still be pinched by the jaws 24 or may be disengaged from the
jaws (as
illustrated).
After this operation, the compacted cake 6 is ejected from the press by a
central part
26 of the lower mould portion moving upwardly relative to the outer part of
the
portion to force the compacted cake out of the mould portion 12 (Fig. 9).
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The compacted cake including the insert is then sealingly packed between the
two
foils 2, 3 which are sealed at the peripheral seam (not shown).
A second embodiment of the process of the invention is illustrated in relation
to Figs.
to 17. In order to avoid undue repetitions, only the main differences compared
to
the first embodiment will be described whereas the other characteristics and
features
of the method and/or apparatus will appear to the skilled person as applicable
to this
embodiment For this also, the same numerical references are used to designate
the
same or similar technical means, axis, planes and directions.
As shown in Fig. 10, in this second embodiment, the press 10 comprises a lower
mould portion 12 which is filled with a partial mass of powder 16 by the
powder
feeder 14. By "partial mass of powder" it is meant here that only a part of
the total
predetermined amount of powder due for making the final capsule is filled in a
preliminary filling operation. For this, the size of the cavity 17 of the
mould portion
12 is adapted to receive the partial mass of powder. The size of the cavity
can be
reduced compared to the size of the cavity which would be necessary for
receiving the
total amount of powder due to produce the final powder cake. The size
reduction of
the cavity can be obtained by different means. In the illustrated example, it
is obtained
by providing a size adjustable part 27 of the lower mould portion. The part 27
can be
a central part which is moved relative to a circumferential part 28 of the
lower mould
portion until the proper size of reduced cavity is obtained.
Once the partial mass of powder is filled as illustrated in Fig. 11, an upper
mould
portion 13 is lowered relative to the lower mould portion 12 to compact the
partial
mass. The upper mould portion 13 may not necessarily comprise a recess forming
surface but can simply comprise the outer shape forming surface 18, i.e., a
convex
surface, to form one extended side of a partial powder cake. After this first
stroke (Fig.
12), a partial compacted cake of powder 29 is obtained. The size of the cake
is
reduced compared to the final compacted cake to be produced for the capsule.
In the next operation, the insert is used to provide a recess in the partial
compacted
mass. The insert 9 is placed by means of the insert feeder 15 in this partial
compacted
cake. It results that the insert engages only partially in the partial
compacted cake
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while a portion of the insert remains outside of the cake 29. As a possible
variant, the
recess could also be made by a recess forming surface or protrusion protruding
from
the surface of the upper mould portion 13.
In the next operation, a second powder filling operation takes place (Fig.
14). The
same powder feeder 14 can be used to complete the filling of the cavity. The
cavity
can be re-sized to accommodate the second desired amount of powder necessary
to
complete the mass of powder. Then, a second stroke is carried out by the upper
mould
portion 13 or another mould portion to form the outer shape of the final
compacted
cake (Figs. 15 and 16). In the next operation, the final compacted cake 30 is
removed,
e.g., by moving the central part 27 upwardly or axial direction A until to
eliminate or
reduce the size of the cavity (Fig. 17).
As discussed, the rotary press described in relation to the figures is
presented as a
preferred example, but it could be replaced by another type of press in which
the
powder is fed into the mould portions by effect of a linear movement relative
of the
mould portions (or plate containing them) and the powder feeder.
