The present invention concerns apparatuses for pressing of edible
articles comprising a holding device with at least one cooling channel and carrying
a number of suspended, cooled plungers which is pressed into the mass. Many types
of mass may apply as long as the mass is capable of reaching a deformable state
before being pressed into shape. Chocolate mass, whether it is in a highly liquid
state, a thick paste-like, viscous state or in a powder form may for example apply.
The chocolate mass may have a content of genuine cocoa butter or simply be a so-called
chocolate-like mass by which the butter is substituted with other kinds of fats
or oils such as palm-kernel oils. Decisive is, that the particular mass in question
is deformable by the pressing action of cold plungers.
The mass may be deposited in underlying mould cavities or directly
upon a conveyor belt before the pressing operation. The intention could also be
to press or stamp a covering chocolate layer deposited upon a previously made edible
article, such as a chocolate article or a biscuit. The covering layer to be pressed
could for example be a bottom covering layer deposited upon a centre mass deposited
into the inner cavity of a pre-made chocolate shell or a covering layer deposited
upon a bar-shaped centre.
An inner chocolate layer on pre-made articles could also be made,
for example by depositing tempered chocolate-like mass in an already made shell,
optionally shaking the moulds, and then immersing cold plungers into the deposited
mass for making shells with predetermined and even thickness. The first pre-made
shell could be of one chocolate type such as ordinary milk chocolate and the inner
chocolate layer made subsequently could be of another chocolate type, such as a
white chocolate type.
When for example shells are to be made, an apparatus comprises a plate-like
holding device carrying a number of cooled plungers to be immersed into underlying
mould cavities in a mould plate. In each mould cavity is deposited liquid chocolate,
and by lowering the holding device, the plungers are simultaneously immersed into
the chocolate in the different mould cavities. By the pressing action of the plungers,
the chocolate mass is pressed into shells having the desired shape. Due to the cooling
of the plungers a forced solidification of the influenced chocolate mass is achieved
in contact therewith. The chocolate mass then contracts slightly and releases the
pressing surfaces of the plungers which may be lifted up and free therefrom within
Generally, chocolate masses are suspensions of non-fat particles such
as sugar, milk powders and cocoa solids mixed up with a liquid fat constituent.
Often, the fat phase comprises genuine cocoa butter of until around 30%, but may
comprise substitutes as well. Such substitutes can be in the form of other types
of fat-containing oils. Chocolate types where the cocoa butter has been replaced
wholly or partly by other fats are often named commercially as compound chocolate,
in which the cocoa butter has been replaced by palm-kernel oil. Mass made of 100%
fat in the form of cocoa butter or the like as compound is also possible.
However, for the chocolate-like masses it is decisive, that whether
the fat phase constitutes of genuine cocoa butter or substitutes thereof, the fat
phase is capable of crystallizing into stable crystal types, such as the β-crystals
developing in genuine cocoa butter when the mass solidifies.
Before being supplied in liquid state to the apparatus, the chocolate
is typically being treated for providing stable beta-V crystals at solidification.
The treatment could be a tempering process by which the mass is generally brought
to around 40-50°C, where after it is being cooled to around 25-34°C, so that crystallisation
is initiated. Then the mass is reheated around 0,5-2,0°C for re-melting most of
the in-stable crystals in the mass, however preserving a content of stable βV-crystals,
which melts at a higher temperature than the in-stable crystals. The stable crystals
are preserved in the mass ready for depositing in an amount of typically 0,01% -
5%, preferably in an amount of 0,1% - 2%. Before being supplied the chocolate could
also be treated by other processes such as cooling the chocolate to around 30-34°C,
then seeding it with already made powder having a content of desirable beta V crystals
for ensuring the solidification into proper crystals.
After the shells made have solidified, they may be filled with a centre
mass of a creamy or liquid food material, which differs from that of the shell material.
The centre mass could be an alcohol containing mass, a sugar containing mass or
a creamy fondant mass, simply any of the centre masses known to the chocolate industry.
Finally, a chocolate covering layer may be deposited for closing the centre mass
off, thereby creating a complete article. The articles could have any shape, size
and configuration and could typically be "pralines", tablets, or slabs such as for
example the well-known quadrangular slabs or tablets with all kind of centre masses,
crunchy or creamy.
Advantageously, the chocolate covering layers can be pressed with
an apparatus according to the invention, however, also chocolate covering layers
deposited upon other types of edible articles may advantageously be pressed with
the inventive apparatus. Edible articles such as bars, biscuits or bakery articles
are generally excellent to provide with a chocolate covering layer being pressed
by the inventive apparatus.
If a bottom covering layer is not created on a pre-made shell, the
articles made by the apparatus could typically be figures or eggs or egg-like articles,
which are created by joining together two chocolate shells with each other. Both
shell halves may be made with the inventive apparatus, and a centre mass may be
deposited before the halves are being joined. Instead of a centre mass the cavity
between the joined shells could simply contain some kind of surprise, such as a
small plastic container comprising kids toys inside the well-known "Surprise" eggs.
WO 98/52425 (KMB, Knobel) discloses an apparatus having numerous plungers
permanently fixed to a carrier or holding plate. The carrier plate as well as the
plungers comprise major inner channels through which cooling liquid is forced to
flow for achieving the necessary cooling of the plungers. Such construction may
be used when relatively large articles such as Easter eggs or surprise eggs are
to be made. However, the inner channels of the plungers makes it expensive to manufacture.
When smaller articles are to be produced, the smaller plungers with inner channels
becomes difficult, very expensive and if not impossible to make. Furthermore, the
inner channels of such small or slim plungers becomes insufficient for providing
the necessary cooling to the plungers and then to the chocolate being pressed. The
plungers are fixed to the plate-like holding device and is impossible to replace
with other plungers having different configuration, shape or size.
WO 98/52425 (KMB, Knobel) furthermore discloses, that the plungers
are arranged with substantial mutual distance at the holding device without consideration
to an optimal utilization of the fixed surface area of the mould plates. The result
is a production capacity being considerably lower than desired. For the manufacturer
of the chocolate articles it is of outmost importance for his economy to press as
many articles as possible each time the holding device makes a pressing operation.
EP 0923876 A discloses an apparatus of the introductory type and by
which the independently suspended plungers are made in one solid piece with the
same cross-sectional shape in all of their length. The upper part of each plunger
comprises sliding surfaces and is arranged vertically movable in a hole in the holding
device. Sliding surfaces of the upper part is then supported by opposite sliding
surfaces of the hole in the holding device.
The sliding surfaces transmits cooling from the holding device and
to the pressing surfaces for cooling the warmer chocolate when being pressed. Each
plunger may be further supported by an upper slim slide guidance.
However, plungers with such length as disclosed in the EP-publication
and in practice being between 50-100 mm necessary for obtaining proper support by
the opposite sliding surfaces of the holding device, is very expensive to manufacture.
Complex shapes of the articles available on today's market requires that the plungers
are made with complex cross-sectional shapes as well.
The lower part of the plungers having the pressing surfaces is created
with the exact shape for making the inside or contour of the pressed chocolate articles.
As disclosed in the EP-publication the same exact cross-sectional shape is preserved
all the way up through the upper plunger part and to the top thereof incorporating
the sliding surfaces of the plunger.
The disclosed configuration requires the best and most accurate technologles
within the art of tool-making with the consequence, that the manufacturing expenses
of the plungers becomes excessively high. The expenses of making the corresponding
openings with the opposite sliding surfaces in the holding device are high as well.
The sliding surfaces of the openings as well as the sliding surfaces of the plungers
are made with very fine tolerances for obtaining proper and un-problematic function
during long-time pressing of articles.
In total, the manufacturing expenses of making the plungers and the
corresponding openings of the holding device becomes a major part of the apparatus,
which typically carries between 50 and 200 plungers depending on the size of the
articles to be pressed.
As the expenses of making the plungers and the corresponding holes
with the opposite supporting gliding surfaces in the holding device constitutes
a substantial part of the total expenses of manufacturing the apparatus, it becomes
important to reduce the expenses of making the plungers and the supporting holes
in the holding device.
The holding device and the plungers are furthermore only adapted to
make articles with one specific shape and configuration as determined by the configuration
of the pressing surfaces and cross-sectional shape of the plungers being preserved
all the way to the top working in the holding device. Articles with other configurations
and shapes are impossible to make with the same apparatus. Every time a differently
configured article is to be produced with the same apparatus another holding device
with differently shaped openings with slide surfaces and a correspondingly shaped
new set of plungers must be produced.
For the manufacturer of the chocolate articles it is crucial to his
business to achieve as high capacity as possible of the apparatus, so that as many
articles as possible are pressed within a given time period. Consequently, the apparatus
must produce as many articles as possible per pressing operation, i.e. each time
the holding device is lowered against the underlying mould or conveyor belt.
When the articles are pressed in mould cavities, the available area
for pressing the articles is determined by the size of a standard mould, which typically
has a width of 275 mm and a length of 625 mm. Within this area as many mould cavities
and corresponding plungers must be arranged for reaching as high pressing capacity
of the apparatus as possible. A decisive factor for reaching as high production
capacity of the apparatus as possible is then the compactness of the arrangement
of the plungers at the holding device.
A problem to solve is to provide an apparatus of the introductory
art, which can be used for making differently shaped products without changing the
holding device for the multiple plungers.
Another problem to solve is to provide an apparatus by which the holding
device is considerably simpler and less cost expensive to produce than the prior
The apparatus according to the present invention is characterized
in, that the upper part has a circular cross-section and the lower part has a non-circular
cross-section, and that the parts are separate parts, which are joined together.
Hereby is obtained, that the holding device and the movable, upper
plunger parts arranged in the openings with the sliding surfaces are made in the
simplest possible manner as a separate unit independent of the required shape and
geometry of the articles to be made. The lower plunger parts comprising the complex
geometry of the pressing surfaces are also made as separate units, which are then
joined to the upper plunger parts in the holding device when the articles having
the particular shape are to be produced.
The upper plunger parts as well as the supporting openings in the
holding device all have circular cross-sections and are thereby made by basic, simple
drilling and milling operations. Consequently it have become simple, fast, and cheap
to make the upper plunger parts and especially the supporting holes. The expenses
are typically reduced between 50 and 90%. Only the lower plunger parts are made
with the required non-circular geometry of the articles to be pressed.
For plungers having complex geometries, i.e. cross-sections other
than circular or having relatively slim or small cross-sections it can then be avoided,
that the pressing surfaces of the plungers functions as sliding surfaces supported
by opposite sliding surfaces of the holding device. Every part of the surfaces of
the plungers can be moving outside contact with the holding device, yet is obtained
an efficient heat transport and cooling of the plungers through the upper circular
All of the multiple lower plunger parts may have identical non-circular
shapes as when all the articles to be in each moulding operation are identical in
shape and configuration.
Especially when more than one pressing operation is to be performed
on the same articles, such as when a first operation incorporates pressing of the
shells and the second operation incorporates pressing of a bottom layer thereupon
the solution is advantageous.
An unforeseen flexibility is also obtained as identical holding devices
may be provided with differently shaped lower plunger parts. An apparatus may for
example comprise a first holding device having lower plunger parts with one configuration
for making shells. However, the apparatus may also comprise a second holding device
being identical to the first one apart from the fixed lower plunger parts now having
the shape for pressing a chocolate covering layer as a bottom upon the pre-made
Another advantage is, that the individual lower plunger parts fixed
to the same holding device may have different configuration, so that differently
shaped chocolate articles may be pressed with the same holding device. The mutual
arrangement or pattern of the differently shaped articles pressed in the same pressing
stroke may be transferred directly into a sales box. Cumbersome handling and sorting
of differently shaped articles are thereby avoided.
However, when differently shaped articles are to be produced this
can be done in the one and same production line. Differently shaped lower plunger
parts are simply joined with the upper plunger parts of the same holding device.
The underlying moulds then comprises differently shaped cavities arranged under
the appropriate lower plunger parts. Several differently shaped articles are then
made in the same moulding operation and the need for further moulding lines is avoided.
The differently shaped lower plunger parts may be arranged in a mutual pattern,
which is desirable to be transferred directly into a box, such as a gift box when
the articles,are to be packed.
The utility of the holding device as a separate unit with the upper
plunger parts makes it possible to provide it in different standard configurations
onto which differently shaped lower plunger parts may be fixed for pressing differently
sized articles. One holding device may comprise 40 upper plunger parts having a
diameter of 50mm being evenly distributed over the prefixed holding plate of the
device. The lower plunger parts fixed to that holding device could for example have
a configuration for making shells for slabs. Another holding device having the same
size of the holding plate may comprise 60 evenly distributed upper plunger parts
having a diameter of 35 mm. The lower plunger parts to be fixed to that holding
device could for example have the configuration adapted to press a chocolate covering
layer of a biscuit. Yet another holding device having the same size of the holding
plate may comprise 80 evenly distributed upper plunger parts having a diameter of
25 mm. The configuration of the lower plunger parts suitable for this configuration
of the holding device may for example be suitable for pressing shells for "Pralines"
or bottom coverings thereof.
The apparatus may comprise a closure plate having openings through
which the lower plunger parts extends, and which is movably suspended below the
holding device. When lowering the holding device during a moulding and pressing
action the closure plate comes to rest upon the upper surface of the mould plate.
Thereby a completely tight closure of the mould cavities are achieved before the
holding plate and consequently the lower plunger parts are lowered further and under
pressure causes the chocolate mass to completely fill out the moulding cavities.
Subsequently cutting of the upper rims of the articles are then unnecessary and
dirtying of the moulds and production facilities with cut-off particles of chocolate
is then avoided.
The invention is explained further below by reference to preferred
embodiments as well as the drawing, in which
- fig. 1 is a schematical, perspective view of part of a production plant according
to the invention,
- fig. 2 is a schematical view of a first holding device, seen from below without
any lower plunger parts,
- fig. 3 is a schematical section of a part of the holding device, for clarity
disclosing only one plunger and one underlying mould cavity with deposited chocolate
- fig. 4 is the same disclosed in a lower position by which the closure plate
of the holding device has come to rest upon the mould plate,
- fig. 5 is the same disclosed in the lowermost position of the holding device
and the plungers at which the chocolate is pressed to complete filling out of the
- fig. 6 is a schematical section of a part of a further holding device, which
is adapted to press on top of a covering layer deposited on top of the previously
made chocolate article by the first holding device,
- fig. 7 is a schematical, perspective view of the completed chocolate article
made by the apparatus and plunger shapes disclosed in figures 2-6,
- fig. 8 is a schematical, perspective view of another shape of the lower plunger
part for pressing traditional, "Praline"-like shells, and
- fig. 9 is a schematical section of another holding device, by which each plunger
is joined with two upper plunger parts with circular section.
The apparatus disclosed in figure 1 constitutes part of a major plant
for manufacturing of chocolate articles. The apparatus comprises a shell moulding
section 1, a centre filling station 2 and a bottom covering pressing section 3.
The choice of sections are optional within the inventive idea as only one section
is necessary for performing a pressing operation such as a shell pressing or a bottom
pressing. Neither is the inventive idea limited to any particular configuration
of the articles such as shells as long as the mass simply is capable of being pressed
out. Other examples of articles are tables or bars and pressing of chocolate covering
layers upon pre-made articles such as upon filled shells or upon pre-made biscuits.
A continuously moving conveyor 4 extends through the stations 1, 2
and 3 and carries a great number of juxtaposed mould plates 5. For sake of simplicity
is only disclosed the part of the conveyor 4 running through the depicted stations
1, 2 and 3. Subsequently to the bottom covering pressing station 3 is normally arranged
a cooling tunnel and a wrapping section. Both the disclosed shell moulding section
1 and the bottom covering pressing section 3 comprise the inventive idea.
The schematically disclosed housing 6 comprises some kind of depositor
means, which deposit the edible mass and as in the disclosed example ready tempered
chocolate mass into the individual mould cavities 15 of each mould plate 5. Each
mould plate 5 comprises typically between 50 and 200 mould cavities of which only
one is disclosed for sake of clarity, i.e. fig. 3. Each individual mould plate 5
is then carried on by the conveyor 4 and passes over a shaking table 7, which distributes
the deposited chocolate evenly within the individual mould cavities.
Then the mould plates 5 enters the shell moulding or pressing housing
8, within which the deposited chocolate is pressed by the action of the plungers
into shape of the desired articles. In the moulding housing 8 is arranged a schematically
disclosed holding device 9. The holding device 9 is arranged with known means such
as columns and slides, a motor for creating the movement and related control panels
and software for controlling the up- and down movement of the holding device 9 each
time it is in engagement with a mould plate and shells are pressed in the mould
As disclosed in figures 3-6 the holding device 9 comprises at least
one channel 10 for circulation of a cooling liquid and carries a plurality of independently
suspended plungers 11. Each plunger 11 has a lower part 12 with pressing surfaces
13 to be pressed into contact with the mass 14 in the mould cavity 15. Each plunger
11 also comprises an upper part 16 with sliding surfaces 17 supposed by opposite
sliding surfaces 18 of openings 19 in the holding device 9.
The upper plunger part 16 has a circular cross-section and fits into
the openings 19, which also features a circular cross-section. In figure 2 the holding
device 9 is disclosed from below without the lower plunger parts 12 so that the
circular cross-sections of the upper plunger parts 16 can easily be seen.
As disclosed in figures 3-6 the lower plunger parts 12 are joined
with the upper plunger parts 16, for example by simple screw joints 20, so that
the lower parts 12 fast and easily may be changed with parts having different configurations.
The upper plunger parts 16 and the supporting openings 19 of the holding
device 9 are simple and cheap to make by basic drilling and milling operations.
Only the lower plunger parts 12 are made with the required non-circular geometry
of the articles to be pressed. The expenses of making the holding devices are typically
reduced with 50-90% in comparison with the prior art. Each holding device may furthermore
be fitted with lower plunger parts 12 having essentially any configuration and shape
so that a holding device with plungers fitted are not limited to the pressing of
only one specific article with particular shape and configuration as by the prior
The apparatus may advantageously be fitted with a closure plate 21
having openings 22 through which the lower plunger parts 12 extends, and which is
movably suspended below the holding device 9.
Before a pressing operation the holding device 9 is brought in line
with the next underlying mould plate 5 so that each plunger 11 is exactly above
an underlying mould cavity 15 in the particular mould plate 5. During the pressing
operation the conveyor 4 is stopped or the holding device is forces to run synchronously
with the same speed as that of the conveyor 4. In the secondly mentioned option
the holding device is retracted to its initial starting position after completion
of a pressing operation and so that a new may be initiated.
Before the actual pressing operation the holding device 9 is lowered
to such extend, that the closure plate 21 has come to engagement with the upper
surface 23 of the underlying mould plate 5 so that safe enclosure of the pressing
cavity is obtained as depicted in figure 4.
The closure plate 21 is typically suspended by a non-disclosed spring
means to the holding device, so that by the further lowering of the holding device
the closure plate is kept pressed on to the upper surface 23 of the mould plate
5. The multiple plungers 11 of the holding device then moves further on into engagement
with the chocolate mass 14 by the continuing lowering of the holding device 9. The
mass is pressed out into complete filling out of the enclosed cavity as disclosed
in figure 5 so that the full geometry of the desired articles 24 are obtained. The
upper plunger parts 16 may be acting against a spring-load created by spring-means
or pressurized air between the plunger part 16 and the holding device 9, for example
transferred via a slim guide pin 25. Gaskets 26 may be arranged for supporting the
periphery of the plunger part 16 and closing off the gap between the sliding surfaces
After the pressing of the articles 24 is completed, the holding device
is retracted to its upper position being ready for a new pressing to follow.
During the pressing circulation of cooling liquid through the channels
10 of the holding device is controlled by the schematically depicted unit (44) connected
with the channels via hoses 27. The unit comprises a cooling device for keeping
a constant temperature of the circulating liquid or for keeping a constant temperature
at a surface, such as typically the pressing surfaces 13 of the lower plunger parts
12. The temperature may advantageously be as low as between +5 and - 25 degrees
Celsius, however decisive is, that the temperature of the pressing surfaces is kept
below the solidification temperature of the particular mass being pressed. The pressing
surfaces are typically of high gloss and are free of any lubricant.
An air drying device 28 is connected to the housing 8 via a hose 29
and is adapted to blow or circulate dry air through the housing 8. The humidity
may be lowered to such extent, that no condensation is created on the pressing surfaces
whatever the temperature of the pressing surfaces may be. However, for the pressing
of some masses it may also be desirable, that the dewpoint-temperature of the air
is slightly above the surface temperature of the pressing surfaces. Decisive is
that the humidity is regulated in accordance with the actually required need for
the articles to be pressed.
By the particular embodiment, the mould plates 5 with the ready pressed
shells or tablets 24 are moved on through the centre filling section 2, at which
an optional centre mass such as cream or a crunchy mass 30 is deposited into the
inner cavity of each tablet 24. Advantageously, the mould plates 5 passes over a
shaking table 31 for obtaining secure spreading of the centre mass 30 in the tablet
or shell 24.
Thereafter, the mould plates passes into a station for depositing
a chocolate covering 43 on to the articles 24 for closing of the centre mass 30.
The mould plate 5 moves on into the final bottom covering pressing station 3. The
station 3 is in principle identical to the station 1 apart from that the lower plunger
parts 12 have been replaced by lower plunger parts 33 with flat pressing surfaces
34 for pressing of the covering 43.
Then the station 3 comprises a holding device 9 functioning in exactly
the same manner as that of station 1 as depicted in figure 6 where the pressing
of the covering layer 43 is disclosed. As depicted in figure 1 a unit (44) may also
be arranged for controlling the temperature of the cooling liquid and a drying unit
28 may be arranged for controlling the humidity of the housing 8 of the station
3. The ready made chocolate article 35 is disclosed in figure 7.
Another example of a plunger 36 according to the inventive idea is
disclosed in figure 8 in exploded view. The plunger comprises an upper part 37 with
circular cross-section and a lower part 38 with non-circular cross-section. The
lower part 38 with non-circular cross-section is more cubic-like and is adapted
for the pressing of chocolate shells for articles such as "Pralinen". The joining
between the upper part 37 and the lower part 38 is disclosed with tight-fitting
friction means or surfaces 39, 40.
In figure 9 is disclosed another example of a holding device 45, by
which each lower plunger part 41 is joined with two upper plunger parts 42. The
configuration is useful when odd shaped of the articles are to be made. In the example
disclosed a long, slim cross-section of the lower plunger part 41 is to be used
for obtaining the desired geometry of the articles to be pressed. By joining the
lower plunger parts with such configurations with at least two upper plunger parts
42 having smaller circular cross-sections in stead of joining them with only one
upper plunger parts, the plungers may be arranged closely to each other at the holding
device (45) and yet is sufficient cooling of the lower plunger parts 41 achieved
through the multiple upper plunger parts 42. The closer arrangement of the lower
plunger parts 41 to each other obtains a high number of mould cavities in each mould
plate and consequently an optimal high number of articles to be pressed in each
When differently shaped articles are to be produced this can be done
in the one and same production line. Differently shaped lower plunger parts are
simply joined with the upper plunger parts of the same holding device. The underlying
moulds then comprises differently shaped cavities arranged under the appropriate
lower plunger parts. Several differently shaped articles are then made in the same
moulding operation and the need for further moulding lines is avoided. The differently
shaped lower plunger parts may be arranged in a mutual pattern, which is desirable
to be transferred directly into a box, such as a gift box when the articles are
to be packed.