Patent Application
20220233015
The invention relates to an apparatus for releasing an ingredient from a capsule, in particular a coffee capsule for a capsule-based coffee machine. The invention also relates to the capsule-based coffee machine itself.
Capsule-based coffee machines are well known. A capsule-based espresso coffee machine includes a capsule holding assembly for holding a capsule in position. During brewing, water is injected into the capsule by a high pressure pump. A pressure in the capsule is established that leads to the puncturing of the cover against a puncture plate, for example known as a stud plate.
Once the capsule is punctured, the coffee can be released from the capsule through the punctured perforations, and through the stud plate. The beverage is then collected at a coffee outlet.
An espresso coffee beverage combines a liquid part and a crema layer. The crema layer should have a fine and smooth consistency, formed by microbubbles. However, the turbulent jets created by the high pressure process can result in a coarse consistency, with undesirably large bubbles formed in the crema.
In particular, investigations carried out by the applicant have shown that the exit flow from the stud plate can create strong jets and these jets may also include large bubbles caused by turbulence at the output of the stud plate. If these jets lead directly to the coffee outlet, large bubbles can be formed in the crema layer.
One approach which has been proposed (but not yet published) by the applicant is to provide a barrier between the output jets from the stud plate and the coffee flow to the coffee outlet. This avoids a direct path from the stud plate to the coffee outlet.
The applicant has also found that if the jets from the stud plate impact on the crema flow which then leads to the coffee outlet, undesirable large bubbles can still be introduced into the flow, even if there is no direct flow from the stud plate to the coffee outlet. This provides another mechanism by which the crema can have a coarse consistency.
There remains a need for an apparatus for releasing the capsule contents while maintaining a smooth and fine consistency of the delivered capsule ingredient.
The invention is defined by the claims.
According to examples in accordance with an aspect of the invention, there is provided an apparatus for releasing an ingredient from a capsule, comprising:
a chamber for receiving a capsule, the capsule having a top cover;
a stud plate comprising a set of openings for receiving the capsule contents as pressurized jets after rupture of the top cover;
an outlet for delivery of the capsule contents; and
a jet shaping unit downstream of the stud plate, comprising a set of one or more jet shaping elements, each associated with a respective set of one or more of the openings of the stud plate.
This apparatus releases the capsule contents to create a set of pressurized jets through a ruptured top cover, in conventional manner. However, these jets pass through a jet shaping unit. In particular, some or all of the orifices, and hence jets, are associated with a jet shaping element. The jet shaping elements for example catch or guide the jets and thereby reduce the flow speed of the jets. This prevents high speed jets impinging directly on the general flow to the outlet, and thereby avoids formation of large bubbles in that general flow.
The openings are preferably tapered, having a wide end and a narrow end, wherein the narrow end of the openings are for receiving the capsule contents. A jet is thus created at the narrow end, and is formed at the transition between the ruptured cover and the narrow ends of the openings. Burrs on the stud plate will create a flow having a direction and turbulence which cannot accurately be predicted or controlled. Thus, the jets may not have desired characteristics and may result in a coarse crema when they impact on the flow to the outlet. The jet shaping elements slow the jets before they reach the flow to the outlet.
The apparatus may further comprise a deflector positioned between the stud plate and the outlet. This is used to prevent a direct path from the jets to the outlet. The deflector may be a separate plate or it may be an integral part of a collector unit downstream of the chamber.
The jet shaping unit may for example be integrated with the stud plate or with the deflector plate, or again with a collector unit downstream of the chamber. This means the jet shaping unit does not require any additional component to be introduced into the design.
In one example, the jet shaping elements may each comprise a projection which projects towards a respective opening of the stud plate. Thus, the jet flow from the stud plate opening impinges on the projection, which thereby reduces the flow rate.
The openings of the stud plate may for example be conical and the projections have conical ends which project into the tapered openings. In this way, a spacing is defined into which the jet flow is diverted.
In another example, the jet shaping elements may each comprise an orifice of an orifice array, with the orifices aligned with the openings. These orifices may be considered to elongate the design of the stud plate, so that it has openings followed by a cylindrical channel. Any jet flow not directly aligned with the channel will strike the channel wall, so that overall the jet flow loses energy.
The invention also provides a capsule-based espresso coffee machine comprising:
a water reservoir;
a pressurizing system; and
an apparatus as defined above, for releasing the contents of the capsule under pressure, wherein the outlet of the apparatus defines or is coupled to an outlet of the coffee machine.
The release apparatus may thus form part of a capsule-based espresso coffee machine.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.
For a better understanding of the invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:
The invention will be described with reference to the Figures.
It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the apparatus, systems and methods, are intended for purposes of illustration only and are not intended to limit the scope of the invention. These and other features, aspects, and advantages of the apparatus, systems and methods of the present invention will become better understood from the following description, appended claims, and accompanying drawings. It should be understood that the Figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the Figures to indicate the same or similar parts.
The invention provides an apparatus for releasing an ingredient from a capsule in which a stud plate comprises a set of openings for receiving the capsule contents as pressurized jets. A jet shaping unit is downstream of the stud plate having a set of one or more jet shaping elements. The or each jet shaping element is associated with a respective set of one or more openings of the stud plate. Thus, generally there is a set of jet shaping elements and a set of openings. The jet shaping elements reduce the jet flow velocity and thereby prevent the jets generating bubbles which could otherwise decrease the smoothness of the delivered capsule contents.
The heated water is injected into a brewing chamber 108 and flows into a capsule of ground coffee (not shown) that is inserted in the brewing chamber 108. The capsule may be pierced open by the apparatus on an inlet side of the capsule or the capsule design may include openings so that the capsule does not require piercing. The water injected into the brewing chamber flows into the capsule via these holes or openings. During brewing, the capsule is pressed against a fluid receiving plate also referred to as a stud plate 210, sometimes in the art also referred to as extraction plate, comprising studs 212 and through holes between the studs 212.
The stud plate is arranged on a side which faces, in use, the capsule for opening the capsule under the influence of fluid pressure. More specifically, by virtue of the pressure of the provided hot water which enters into the capsule under pressure, a cover of the capsule, preferably provided in metal such as aluminum, or in plastic, is torn open on so called studs of the stud plate, allowing brewed coffee to flow out of the capsule and through the holes 213 in the stud plate 210. These holes 213 lead to flow channels on the opposite side of the stud plate.
In one particular example, a metal piercer is provided at the back of the capsule, for example with a set of piercing points. This piercer is located into the back of the moving chamber. After the capsule is loaded into the moving chamber, the capsule is pierced when the moving chamber is closed by pushing an actuation lever. It leaves a set (of one or more) distinct holes in the inlet side of the capsule (the smallest end of the cone shaped capsule, opposite the flange).
As mentioned above, an alternative is to have capsules that are already opened at the inlet side.
The capsule cover, which is made of thin aluminium foil (or a plastic foil, or a laminate of different materials), is pressed against the studplate, which has a non-flat surface of the studs 212.
In the particular example of
An opening 206 is provided giving access to a coffee outlet 220 in the form of a first fluid channel, provided as an outlet conduit for guiding brewed coffee away from the collector chamber 204 in a direction away from the stud plate 210. Downstream of the first fluid channel 220, a second fluid channel 122 is provided as a part of a fluid track for providing coffee to a dispensing nozzle 126. The coffee provided by the first fluid channel 220 flows via the slanted second fluid channel 122 in a nozzle collector 124 to which the dispensing nozzle 126 is connected.
The holes and the channels are together described in this application as “openings”. Thus, the openings as a whole are tapered, having a wide end and a narrow end, wherein the narrow end of the openings are for receiving the capsule contents. The narrow ends define the holes 213. These holes 213 for example each lead to a conical void which tapers outwardly from the cone tip, which is the narrow end, to the cone base, which is the wide end. This conical void defines one tapered channel.
Of course, any suitable stud plate design may be used, which enables perforation of the capsule cover on one side and provides a flow path on the other side for the pressurized jets which result.
As shown in both
In this example, the collector chamber 204 is delimited by the stud plate 210 at a first side and by the rear wall 230 at a second side, opposite to the first side.
In this example, the stud plate 210 and the rear wall 230 are provided parallel to one another, the rear wall 230 may be shaped or oriented differently relative to the stud plate 210. The stud plate 210 and the rear wall 230 are in this example connected by a circumferential wall. The collector chamber 204, with the stud plate 210, the rear wall 230, the circumferential wall and the first fluid channel 220 are comprised by a collector module 200.
The rear wall 230 functions as a deflector positioned between the stud plate 210 and the coffee outlet 220. It prevents the jets ejected from the capsule directly passing to the coffee outlet.
The interaction between the capsule cover (e.g. foil) and the stud plate results in a certain back pressure. A pump used to generate the flow needs to overcome that back pressure and when the parameters of the cover, coffee and pump are chosen correctly, good control over the brewing conditions is possible.
A fine crema is desired. However, it can arise that the crema generating behavior is disturbed resulting in large volumes of coarse crema, which does not look appealing to the user.
Investigations have showed that the exit flows from the stud plate sometimes generate strong jets which, when they impact the outflowing coffee, generate large bubbles that flow into the cup and cause the coarse crema.
This is because the coffee is released from the capsule as jets from the openings in the stud plate (the jets are shown as arrows in
The jets originating from the stud plate can impact the coffee flow 240 behind the stud plate. When some or all of these jets are too strong, large bubbles are created. This is especially the case when strong jets are situated in the lower half of the chamber (since the coffee flow has then accumulated).
The jets are generated at the transition between the cover and the holes in the stud plate. They are for example generated by burrs on the stud plate which interact with the cover foil of the capsule. These burrs are difficult to prevent from occurring since they are very common in plastic molded parts such as the stud plate. High flow jets can also occur due to blocking of some of the stud plate holes or due to the capsule cover closing some, but not all, of the stud plate holes.
Thus, it is difficult to prevent undesirable high flow rate jets which may then result in brews with a coarse crema.
For completeness,
A jet shaping unit 400 is added downstream of the stud plate 210, comprising a set of jet shaping elements each associated with a respective one of the openings of the stud plate. In this design, the stud plate 210 can have the same design as shown in
In the example of
The tapered openings of the stud plate 210 have a wide end and a narrow end. The narrow ends are adjacent the capsule cover 302. The tips of the conical ends 404 thus face the narrow ends of the openings in the vicinity of the cover 302.
The emitting jet from an opening in the stud plate thus impinges on the conical end 404 of a respective one of the projections. The flow is then directed into an annular passageway between the conical void of the stud plate opening and the conical ends 404.
This removes energy from the flow and thus reduces the flow velocity. The coffee runs down and around the projections or else runs down the rear wall 230 if the coffee reaches the rear wall.
The projections for example have a length in the range 3 mm to 10 mm and a diameter in the range 2 mm to 6 mm. The diameter of the overall structure, i.e. the capsule diameter, is for example in the range 20 mm to 50 mm.
A jet shaping unit 500 is again added downstream of the stud plate 210, comprising a set of jet shaping elements each associated with a respective one of the openings of the stud plate.
In the example of
The emitting jet from an opening in the stud plate thus impinges on the inner surface of an orifice 502 unless the flow is directed aligned with the orifice axis. Energy is again removed from the flow and thus the overall flow velocity is reduced before the coffee reaches the rear wall, or reaches the flow of coffee down the rear wall to the opening 206.
The plate is for example 2 to 6 mm thick and the diameter of the orifices is for example in the range 2 to 3 mm.
On a front side which faces the capsule, the narrow ends of the stud plate openings are formed. This has the same design as in
The orifices 502 are formed as cylindrical extensions to the wide ends (i.e. the bases) of the (e.g. conical) stud plate openings. The jet shaping unit thus elongates the outlet geometry of the stud plate by adding a cylindrical part to the conical outlet. This elongation allows the jets, which can exit in all different directions, to impact the internal walls of the cylinder. There the fluid sticks to the walls, spreads out and reduces in velocity.
Either design may be integrated with the stud plate or with the rear wall.
The examples above show a stud plate with 24 openings, and a jet shaping unit with 24 elements (orifices or projections). Of course, this is only an example and there may be more or fewer jet shaping elements, for example between 10 and 50 and more or fewer openings, for example between 10 and 100. Furthermore, there may be a different number of openings to the number of elements of the jet shaping unit, for example fewer jet shaping elements than openings. Thus, each jet shaping element may be associated with a respective set of more than one of the openings of the stud plate.
The invention is of primary interest for a coffee machine, and hence for a capsule containing coffee. However, the invention may be applied to a capsule containing another beverage or ingredient. One example of coffee machine has been provided, but this is only by way of example. Many other capsule based coffee machine designs are known and possible to which the invention may be applied. The invention relates specifically to the way coffee (and crema) flow exiting the capsule is processed before delivery to a coffee outlet. Different capsule designs, capsule loading and piercing arrangements (if indeed piercing is needed) and flow arrangements are of course possible.
Variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. Any reference signs in the claims should not be construed as limiting the scope.
| Number | Date | Country | Kind |
|---|---|---|---|
| 19172705.6 | May 2019 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2020/062478 | 5/6/2020 | WO | 00 |
