Patent Publication Number: US-2022233015-A1

Title: Apparatus for releasing an ingredient from a capsule

Description:
FIELD OF THE INVENTION 
     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. 
     BACKGROUND OF THE INVENTION 
     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. 
     SUMMARY OF THE INVENTION 
     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. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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: 
         FIG. 1  shows in schematic form a coffee machine which may be adapted to make use of the release apparatus of the invention; 
         FIG. 2  shows the conventional apparatus for releasing the capsule contents in more detail; 
         FIG. 3  shows the appearance of the stud plate viewed from the side which contacts the capsule; 
         FIG. 4  shows a first example of a modification to the apparatus of  FIG. 2 . 
         FIG. 5  shows the design of the jet shaping unit in more detail; 
         FIG. 6  shows a second example of a modification to the apparatus of  FIG. 2 ; 
         FIG. 7  shows the design of the jet shaping unit in more detail; and 
         FIG. 8  shows that the jet shaping unit may be formed as an integral unit with the stud plate. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     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. 
       FIG. 1  shows one example of a possible design for a coffee machine  100  which may be adapted to make use of the release apparatus of the invention. The coffee machine  100  comprises a housing  190  in which the various functional parts of the coffee machine  100  are provided. The coffee machine  100  comprises a liquid reservoir  102  for holding water or another liquid for preparing the coffee, and a pump  104  for pumping the water to a heater element  106  for heating the water. 
     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  FIG. 1 , the collector module  200  is slidably provided in a collector housing member  110 . Within the collector housing member  110 , the collector module  200  is biased towards the brewing chamber  108  by means of a spring  112  as a biasing member, or is slid by any other mechanism. 
     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. 
       FIG. 2  shows one example of a conventional apparatus for releasing the capsule contents, in more detail, and with a different outlet arrangement.  FIG. 2  additionally shows the capsule  300  with its cover  302  mounted against the stud plate  210 . 
       FIG. 2  shows more clearly how the studs  212  project towards the capsule on one side of the stud plate. When the hydraulic pressure builds up in the appliance due to the pump running, the foils starts tearing at these studs. The pressure is for example around 8 bars (800 kPa), although the required pressure depends on the foil characteristics (such as material type, thickness, hardness, embossing design, weak spots, stud geometry etc.). The result is a number of tears which propagate from the stud tips, and which allow the coffee to flow out towards the set of holes  213  in the studplate and into the spout towards the cup. On the opposite side of the stud plate, the holes  213  lead to the diverging channels shown in  FIG. 2 , and which are deeper than the amount by which the studs  212  project in the opposite direction. Thus, there are shallow studs on one side, and holes in the stud plate which lead to deeper channels on the opposite side of the stud plate. 
     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  FIGS. 1 and 2 , behind the stud plate  210 , a fluid collector is provided, comprising a collector chamber  204  for receiving the brewed coffee provided by the holes in the stud plate  210 . In the collector chamber  204 , in a rear wall  230  defines an upstanding collector wall opposite to the stud plate  210 . 
     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  FIG. 2 ). The jets strike the rear wall  230  and the coffee then runs down to the opening  206 . This coffee flow to the opening  206  is shown as flow arrows  240 . 
     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,  FIG. 3  shows the appearance of the stud plate viewed from the side which contacts the capsule and shows the studs  212  that are pressed into the foil. 
       FIG. 4  shows a first example of a modification to the apparatus of  FIG. 2 . 
     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  FIG. 3 . 
     In the example of  FIG. 4 , the jet shaping elements each comprise a projection which projects towards the respective opening of the stud plate. 
       FIG. 5  shows the design of the jet shaping unit  400  in more detail, and in particular formed as an integral unit with the rear wall  230 . A set of projections  402  extends from the rear wall  230 . The projections  402  have conical ends  404  which project into tapered openings (i.e. the conical void parts) of the stud plate  210 . 
     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. 
       FIG. 6  shows a second example of a modification to the apparatus of  FIG. 2 . 
     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  FIG. 6 , the jet shaping elements each comprise an opening which faces a respective opening of the stud plate. 
     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. 
       FIG. 7  shows the design of the jet shaping unit  500  in more detail. It comprises an orifice plate having orifices  502  which are aligned with the stud plate. 
       FIG. 8  shows that the jet shaping unit may be formed as an integral unit with the stud plate  210 . 
     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  FIG. 3 . 
     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.